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5,000
The detection of HBV DNA with gold-coated iron oxide nanoparticle gene probes
Gold-coated iron oxide nanoparticle Hepatitis B virus (HBV) DNA probes were prepared, and their application for HBV DNA measurement was studied. Gold-coated iron oxide nanoparticles were prepared by the citrate reduction of tetra-chloroauric acid in the presence of iron oxide nanoparticles which were added as seeds. With a fluorescence-based method, the maximal surface coverage of hexaethiol 30-mer oligonucleotides and the maximal percentage of hybridization strands on gold-coated iron oxide nanoparticles were (120 ± 8) oligonucleotides per nanoparticle, and (14 ± 2%), respectively, which were comparable with those of (132 ± 10) and (22 ± 3%) in Au nanoparticle groups. Large network aggregates were formed when gold-coated iron oxide nanoparticle HBV DNA gene probe was applied to detect HBV DNA molecules as evidenced by transmission electron microscopy and the high specificity was verified by blot hybridization. Our results further suggested that detecting DNA with iron oxide nanoparticles and magnetic separator was feasible and might be an alternative effective method.
5,001
Lifeomics leads the age of grand discoveries
When our knowledge of a field accumulates to a certain level, we are bound to see the rise of one or more great scientists. They will make a series of grand discoveries/breakthroughs and push the discipline into an ‘age of grand discoveries’. Mathematics, geography, physics and chemistry have all experienced their ages of grand discoveries; and in life sciences, the age of grand discoveries has appeared countless times since the 16th century. Thanks to the ever-changing development of molecular biology over the past 50 years, contemporary life science is once again approaching its breaking point and the trigger for this is most likely to be ‘lifeomics’. At the end of the 20th century, genomics wrote out the ‘script of life’; proteomics decoded the script; and RNAomics, glycomics and metabolomics came into bloom. These ‘omics’, with their unique epistemology and methodology, quickly became the thrust of life sciences, pushing the discipline to new high. Lifeomics, which encompasses all omics, has taken shape and is now signalling the dawn of a new era, the age of grand discoveries.
5,002
Ebola Virus in West Africa: Waiting for the Owl of Minerva
The evolving Ebola epidemic in West Africa is unprecedented in its size and scope, requiring the rapid mobilization of resources. It is too early to determine all of the ethical challenges associated with the outbreak, but these should be monitored closely. Two issues that can be discussed are (1) the decision to implement and evaluate unregistered agents to determine therapeutic or prophylactic safety and efficacy and (2) the justification behind this decision. In this paper, I argue that it is not compassionate use that justifies this decision and suggest three lines of reasoning to support the decision.
5,003
Advances in the diagnosis and management of influenza
Vaccines are the mainstay of influenza prevention. In the treatment of a likely or certain case of influenza, ion channel inhibitors (amantadine and rimantadine) and neuraminidase inhibitors (oseltamivir and zanamivir) can be effective in reducing the duration of illness in adults. In the absence of a likely or certain influenza diagnosis, ion channel inhibitors or neuramindase inhibitors have lower effectiveness, and symptom relief becomes the rationale for treatment of influenza-like illness. Because both influenza and influenzalike illness are self-limiting, safety of interventions is paramount, especially in children. Echinacea extracts, steam, chicken soup, ipatropium bromide, and oxymetazoline in adults are the interventions that appear to have the best empirical evidence.
5,004
Urbanisation and human health in China: spatial features and a systemic perspective
BACKGROUND, AIMS AND SCOPE: Current studies have paid little attention to the dynamism in urban spatial expansion and its possible environmental and health effects or to the health effects of rapid urban environmental change at different points along the urbanisation gradient. This study adopts a public health ecology approach to systematically understand the relationship between urbanisation, urban environmental change and human health in China. METHOD: Remote sensing image analysis, based on night light data at five different time periods in recent decades, was used to determine changes to the overall urban area. Through a review of the evidence on the relationships between environmental health, urbanisation and health, we advance a pathway framework for explaining urban human health ecology. The Spearman rank correlation coefficient was used to measure the correlation between disease prevalence and urbanisation level, adding a further dimension to a systemic understanding of urban health. RESULTS AND CONCLUSIONS: Urban areas have been increasing spatially, but unevenly, in recent decades, with medium and small cities also expanding rapidly in the past decade. Urbanisation and urban expansion result in changes to land use/coverage change, the urban environment and the residents’ lifestyle, which result in human health problems. Regions with the highest urbanisation level were more inclined to have a high prevalence of chronic disease in recent decades. An ecological public health approach provides insights into the multiple types of data which need to be routinely collected if human disease is not to become a barrier to social and economic development.
5,005
Inhibition of BmNPV replication in Bombyx mori cell by dsRNA triggered RNA interference
RNA interference (RNAi) causes degradation of targeted endogenous RNA in many diverse organisms. To investigate the effect of dsRNA on silkworm cells, we transfected three kinds of synthetic dsRNAs of 435 bp(Ap(1)), 300 bp(Ap(2)) and 399 bp(A(H)) in length against the various regions of BmNPV’s DNA polymerase gene and DNA helicase gene, which are indispensable for viral replication in silkworm cells by TransMessenger(TM) transfection Reagent. Results indicated that in the experiment where silkworm cells were infected with wild-strain BmNPV of the three dsRNAs, Ap(2) and A(H) can effectively suppress the replication of virus, but Ap(1) had no effect on the inhibition of viral replication. Ap(2) and A(H) can reduce the infective titer of BmNPV with a peak change of approximately 3–4 logs on day 4 post-infection. The results of reverse transcript polymerase chain reaction (RT-PCR) and DNA dot blotting also indicated that the expression level of the two target genes and the quantity of viral DNA both distinctly decreased under the influence of Ap(2) or A(H). Furthermore, using fluorescence microscopy we analyzed the distribution patterns of dsRNA. Our studies revealed that a majority of dsRNA was localized in the nuclear periphery discontinuously after 24 h of transfection.
5,006
Structural aspects of antibody-antigen interaction revealed through small random peptide libraries
Two small random peptide libraries, one composed of 4550 dodecapeptides and one of 8000 tripeptides, were synthesized in newly developed credit-card format miniPEPSCAN cards (miniPEPSCAN libraries). Each peptide was synthesized in a discrete well (455 peptides/card). The two miniPEPSCAN libraries were screened with three different monoclonal antibodies (Mabs). Two other random peptide libraries, expressed on the wall of bacteria (recombinant libraries) and composed of 10(7) hexa- and octapeptides, were screened with the same three Mabs. The aim of this study was to compare the amino acid sequence of peptides selected from small and large pools of random peptides and, in this way, investigate the potential of small random peptide libraries. The screening of the two miniPEPSCAN libraries resulted in the identification of a surprisingly large number of antibody-binding peptides, while the screening of the large recombinant libraries, using the same Mabs, resulted in the identification of only a small number of peptides. The large number of peptides derived from the small random peptide libraries allowed the determination of consensus sequences. These consensus sequences could be related to small linear and nonlinear parts of the respective epitopes. The small number of peptides derived from the large random peptide libraries could only be related to linear epitopes that were previously mapped using small libraries of overlapping peptides covering the antigenic protein. Thus, with respect to the cost and speed of identifying peptides that resemble linear and nonlinear parts of epitopes, small diversity libraries based on synthetic peptides appear to be superior to large diversity libraries based on expression systems.
5,007
The Evolutionary Dynamics of Stochastic Epidemic Model with Nonlinear Incidence Rate
A stochastic SIRS epidemic model with nonlinear incidence rate and varying population size is formulated to investigate the effect of stochastic environmental variability on inter-pandemic transmission dynamics of influenza A. Sufficient conditions for extinction and persistence of the disease are established. In the case of persistence, the existence of endemic stationary distribution is proved and the distance between stochastic solutions and the endemic equilibrium of the corresponding deterministic system in the time mean sense is estimated. Based on realistic parameters of influenza A in humans, numerical simulations have been performed to verify/extend our analytical results. It is found that: (i) the deterministic threshold of the influenza A extinction [Formula: see text] may exist and the threshold parameter will be overestimated in case of neglecting the impaction of environmental noises; (ii) the presence of environmental noises is capable of supporting the irregular recurrence of influenza epidemic, and the average level of the number of infected individuals I(t) always decreases with the increase in noise intensity; and (iii) if [Formula: see text] , the volatility of I(t) increases with the increase of noise intensity, while the volatility of I(t) decreases with the increase in noise intensity if [Formula: see text] .
5,008
Growth of exocrine acinar cells on a reconstituted basement membrane gel
Methods have been developed for culturing a dividing population of morphologically differentiated rat parotid, lacrimal, and pancreatic acinar cells in vitro. Isolated acinar cells were plated onto tissue culture dishes coated with a three-dimensional, reconstituted basement membrane gel. After attachment in Ham’s nutrient mixture F12, the cells were cultured at 35°C in F12 supplemented with 10% heat inactivated rat serum, epidermal growth factor, dexamethasone, insulin, transferrin, selenium, putrescine, reduced glutathione, ascorbate, penicillin, streptomycin, and the appropriate secretagogue. Under these conditions, the cells attached rapidly and DNA synthesis was initiated within 2 to 3 d. Although the cells flattened on the substratum, they continued to maintain their differentiated morphology. The cells contained secretory granules, and the secretory enzymes peroxidase and amylase could be detected. The use of a reconstituted basement membrane gel proved critical for the attachment and growth of exocrine acinar cells.
5,009
A Delay Differential Model for Pandemic Influenza with Antiviral Treatment
The use of antiviral drugs has been recognized as the primary public health strategy for mitigating the severity of a new influenza pandemic strain. However, the success of this strategy requires the prompt onset of therapy within 48 hours of the appearance of clinical symptoms. This requirement may be captured by a compartmental model that monitors the density of infected individuals in terms of the time elapsed since the onset of symptoms. We show that such a model can be expressed by a system of delay differential equations with both discrete and distributed delays. The model is analyzed to derive the criterion for disease control based on two critical factors: (i) the profile of treatment rate; and (ii) the level of treatment as a function of time lag in commencing therapy. Numerical results are also obtained to illustrate the feasible region of disease control. Our findings show that due to uncertainty in the attack rate of a pandemic strain, initiating therapy immediately upon diagnosis can significantly increase the likelihood of disease control and substantially reduce the required community-level of treatment. This suggests that reliable diagnostic methods for influenza cases should be rapidly implemented within an antiviral treatment strategy.
5,010
Criminalizing Health-Related Behaviors Dangerous to Others? Disease Transmission, Transmission-Facilitation, and the Importance of Trust
Statutes criminalizing behavior that risks transmission of HIV/AIDS exemplify use of the criminal law against individuals who are victims of infectious disease. These statutes, despite their frequency, are misguided in terms of the goals of the criminal law and the public health aim of reducing overall burdens of disease, for at least three important reasons. First, they identify individual offenders for punishment, a paradigm that is misplaced in the most typical contexts of transmission of infectious disease and even for HIV/AIDS, despite claims of AIDS exceptionalism. Second, although there are examples of individuals who transmit infectious disease in a manner that fits the criminal law paradigm of identification of individual offenders for deterrence or retribution, these examples are limited and can be accommodated by existing criminal laws not devoted specifically to infectious disease. Third, and most importantly, the current criminal laws regarding HIV/AIDS, like many other criminal laws applied to infectious disease transmission, have been misguided in focusing on punishment of the diseased individual as a wrongful transmitter. Instead of individual offenders, activities that enhance the scale of disease transmission—behaviors that might be characterized as ‘transmission facilitation’—are a more appropriate target for the criminal law. Examples are trafficking in human beings (including sex trafficking, organ trafficking, and labor trafficking), suppression of information about the emergence of infection in circumstances in which there is a legally established obligation to disclose, and intentional or reckless activities to discourage disease treatment or prevention. Difficulties remain with justifications for criminalizing even these behaviors, however, most importantly the need for trust in reducing overall burdens of disease, problems in identifying individual responsible offenders, and potential misalignment between static criminal law and the changing nature of infectious disease.
5,011
The Final Size of an Epidemic and Its Relation to the Basic Reproduction Number
We study the final size equation for an epidemic in a subdivided population with general mixing patterns among subgroups. The equation is determined by a matrix with the same spectrum as the next generation matrix and it exhibits a threshold controlled by the common dominant eigenvalue, the basic reproduction number [Formula: see text]: There is a unique positive solution giving the size of the epidemic if and only if [Formula: see text] exceeds unity. When mixing heterogeneities arise only from variation in contact rates and proportionate mixing, the final size of the epidemic in a heterogeneously mixing population is always smaller than that in a homogeneously mixing population with the same basic reproduction number [Formula: see text]. For other mixing patterns, the relation may be reversed.
5,012
Time-series analysis in imatinib-resistant chronic myeloid leukemia K562-cells under different drug treatments
Chronic myeloid leukemia (CML) is characterized by the accumulation of active BCR-ABL protein. Imatinib is the first-line treatment of CML; however, many patients are resistant to this drug. In this study, we aimed to compare the differences in expression patterns and functions of time-series genes in imatinib-resistant CML cells under different drug treatments. GSE24946 was downloaded from the GEO database, which included 17 samples of K562-r cells with (n=12) or without drug administration (n=5). Three drug treatment groups were considered for this study: arsenic trioxide (ATO), AMN107, and ATO+AMN107. Each group had one sample at each time point (3, 12, 24, and 48 h). Time-series genes with a ratio of standard deviation/average (coefficient of variation) >0.15 were screened, and their expression patterns were revealed based on Short Time-series Expression Miner (STEM). Then, the functional enrichment analysis of time-series genes in each group was performed using DAVID, and the genes enriched in the top ten functional categories were extracted to detect their expression patterns. Different time-series genes were identified in the three groups, and most of them were enriched in the ribosome and oxidative phosphorylation pathways. Time-series genes in the three treatment groups had different expression patterns and functions. Time-series genes in the ATO group (e.g. CCNA2 and DAB2) were significantly associated with cell adhesion, those in the AMN107 group were related to cellular carbohydrate metabolic process, while those in the ATO+AMN107 group (e.g. AP2M1) were significantly related to cell proliferation and antigen processing. In imatinib-resistant CML cells, ATO could influence genes related to cell adhesion, AMN107 might affect genes involved in cellular carbohydrate metabolism, and the combination therapy might regulate genes involved in cell proliferation.
5,013
Novel Approaches to Vaccine Delivery
Although the currently available vaccines represent an outstanding success story in modern medicine and have had a dramatic effect on morbidity and mortality worldwide, it is clear that improvements are required in the current vaccine delivery technologies. Improvements are required to enable the successful development of vaccines against infectious diseases that have so far proven difficult to control with conventional approaches. Improvements may include the addition of novel injectable adjuvants or the use of novel routes of delivery, including mucosal immunization. Mucosal delivery may be required to provide protection against pathogens that infect at mucosal sites, including sexually transmitted diseases. Alternatively, novel approaches to delivery, including mucosal administration, may be used to improve compliance for existing vaccines. Of particular interest for safer mass immunization campaigns are needle-free delivery devices, which would avoid problems due to needle re-use in many parts of the world and would avoid needle-stick injuries.
5,014
Monolayer culture of cells originating from apreimplantation bovine embryo
The objective of this study was to establish a method by which trophectodermal cells originating from individual preimplantation bovine embryos could be perpetuated in monolayer culture. A single, Day-11 bovine embryo collected nonsurgically from a mixed-breed beef cow was cultured in Ham's F10 medium supplemented with fetal bovine serum, sodium pyruvate, insulin and epidermal growth factor. After 13 d in culture the embryo had adhered to the surface of the plastic culture vessel and a monolayer covering 0.3 cm(2) had developed in the manner of a tissue explant. The monolayer was successfully dispersed using trypsin-EDTA and the cells were passaged Expansion to a 25-cm(2) flask was achieved by the 4th passage. By passaging cultures at a dilution ratio of 1∶2, cells were maintained for 38 passages before growth slowed. Transfers beyond the 44th passage were unsuccessful. The cell line, designated BE-13, was successfully frozen and thawed at the 9th, 12th, 15th, and 20th passages. The cell line contains both mono- and binucleate cells with a prominent rough endoplasmic reticulum characteristic of ruminant trophoblast cells. Susceptibility to eight bovine viruses was demonstrated. Such cell lines may provide inexpensive systems for the study of trophoblast metabolism and for investigation of the role of the trophoblast in the pathogenesis of selected bovine abortifacient diseases. Because of their range of viral susceptibility, these cells might also be useful for diagnostic purposes.
5,015
First report of molecular identification of Cystoisospora suis in piglets with lethal diarrhea in Japan
Cystoisospora suis is a pathogen that causes diarrhea in pigs and can lead to serious disease. Species identification, especially by histopathological examination, is often difficult because of morphologically similar parasites such as Eimeria species. In this study, we used histopathological, bacteriological, virological, and parasitological methods to identify the cause of the disease in two piglets with severe diarrhea. Villous atrophy, diffuse necrosis, and flattening of mucosal epithelial cells were found in the ilea of examined piglets, and coccidian parasites were found in the cytoplasm of the epithelial cells. In some merozoites in the meronts, the presence of two nuclei indicated type 1 merozoites, characteristic of C. suis. According to Cystoisospora-specific PCR targeting the rRNA internal transcribed spacer 1 (ITS1) gene, the sequences of the products were 98.5% similar to those of C. suis. Escherichia coli (O149 serogroup) exhibiting a virulence factor profile (LT, STb, and EAST1 as toxins and F4 as a colonization factor) was detected in one piglet. No other bacteria or significant enteric viruses were found. Co-infection with C. suis and E. coli could imply aggravation of the disease, although further study is needed to assess the pathogenicity of this interaction. This study is the first to clarify by molecular analysis the sequences of C. suis detected in piglets in Japan.
5,016
Informational Landscapes in Art, Science, and Evolution
An informational landscape refers to an array of information related to a particular theme or function. The Internet is an example of an informational landscape designed by humans for purposes of communication. Once it exists, however, any informational landscape may be exploited to serve a new purpose. Listening Post is the name of a dynamic multimedia work of art that exploits the informational landscape of the Internet to produce a visual and auditory environment. Here, I use Listening Post as a prototypic example for considering the creative role of informational landscapes in the processes that beget evolution and science.
5,017
Adherence and colonization by bacterial pathogens in explant cultures of bovine mammary tissue
Explant cultures of bovine mammary tissue taken from virgin heifers were used to examine adherence, colonization and cytopathogenesis ofStreptococcus uberis, Streptococcus agalactiae, Streptococcus dysgalactiae, Staphylococcus aureus andEscherichia coli in the putative target tissue. None of the five bacteria was able to adhere to healthy ductular epithelium but all showed a marked tropism for exposed connective tissue.S. aureus andE. coli induced a marked cytopathic effect in ductular epithelium after 6 hours in culture but the bacteria were not in close association with the affected tissue. No evidence could be found to support the hypothesis that adherence to epithelium might be the first stage in the pathogenesis of mastitis caused by these organisms.
5,018
An Epidemic Patchy Model with Entry–Exit Screening
A multi-patch SEIQR epidemic model is formulated to investigate the long-term impact of entry–exit screening measures on the spread and control of infectious diseases. A threshold dynamics determined by the basic reproduction number [Formula: see text] is established: The disease can be eradicated if [Formula: see text] , while the disease persists if [Formula: see text] . As an application, six different screening strategies are explored to examine the impacts of screening on the control of the 2009 influenza A (H1N1) pandemic. We find that it is crucial to screen travelers from and to high-risk patches, and it is not necessary to implement screening in all connected patches, and both the dispersal rates and the successful detection rate of screening play an important role on determining an effective and practical screening strategy.
5,019
Transmission Dynamics of an SIS Model with Age Structure on Heterogeneous Networks
Infection age is often an important factor in epidemic dynamics. In order to realistically analyze the spreading mechanism and dynamical behavior of epidemic diseases, in this paper, a generalized disease transmission model of SIS type with age-dependent infection and birth and death on a heterogeneous network is discussed. The model allows the infection and recovery rates to vary and depend on the age of infection, the time since an individual becomes infected. We address uniform persistence and find that the model has the sharp threshold property, that is, for the basic reproduction number less than one, the disease-free equilibrium is globally asymptotically stable, while for the basic reproduction number is above one, a Lyapunov functional is used to show that the endemic equilibrium is globally stable. Finally, some numerical simulations are carried out to illustrate and complement the main results. The disease dynamics rely not only on the network structure, but also on an age-dependent factor (for some key functions concerned in the model).
5,020
Studying plant genome variation using molecular markers
The authors’ studies on the organization and variation of plant genome with the use of molecular markers are briefly reviewed with special emphasis on random amplified polymorphic DNA (RAPD), inter simple sequence repeat (ISSR), sequence characterized amplified region (SCAR), and cleaved amplified polymorphic sequence (CAPS) markers detected with the use of polymerase chain reaction (PCR). These markers have been demonstrated to be promising for identifying cultivars and determining the purity of genetic strains of pea. Genetic relationships between strains, cultivars, and mutants of pea have been studied. The role of molecular markers in molecular genetic mapping and localizing the genes of commercially important characters of pea has been shown. The possibility of the use of molecular markers for studying somaclonal variation and detecting mutagenic factors in plants during long-term spaceflights is considered. The prospects of using DNA markers for understanding the organization and variability of higher plant genomes are discussed.
5,021
Eco-cultural health, global health, and sustainability
Anthropogenic stress on the earth’s ecosystems has resulted in widespread prevalence of ecosystem distress syndrome, a quantifiable set of signs of ecosystem degradation. At the same time, the planet is witnessing rapid declines in global cultural diversity and in the vitality of the world’s cultures, which closely mirror, and are interrelated with, ecological degradation. As a consequence of this converging crisis of loss of ecosystem and cultural health, global health and sustainability are increasingly under threat. An eco-cultural health perspective based on understanding the linkages between human activities, ecological and cultural disruption, and public health is essential for addressing these threats and achieving global sustainability.
5,022
Analysis of codon usage in Newcastle disease virus
In this study, the relative synonymous codon usage (RSCU) values, effective number of codon (ENC) values, nucleotide contents, and dinucleotide were used to investigate codon usage pattern of each protein-coding gene and genome among 31 Newcastle disease virus (NDV) isolates. The result shows that the overall extent of codon usage bias in NDV is low (mean ENC = 56.15 > 40). The good correlation between the (C + G)(12)% and (G + C)(3)% suggests that the mutational pressure, rather than natural selection, is the main factor that determines the codon usage bias and base component in NDV. It is observed that synonymous codon usage pattern in NDV genes is gene function and geography specific, but not host specific. By contrasting synonymous codon usage patterns of different NDV isolates, we suggest that more than one genotype of NDV circulates in waterfowl in USA; and gene length has no significant effect on the variations of synonymous codon usage in these virus genes. CpG under-represented is a characteristic for NDV to fit in its host. These results not only provide an insight into the variation of codon usage pattern among the genomes of NDV, but also may help in understanding the processes governing the evolution of NDV. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11262-011-0574-z) contains supplementary material, which is available to authorized users.
5,023
Epidemiology is ecosystem science
This paper primarily argues that Epidemiology is Ecosystem Science. It will not only explore this notion in detail but will also relate it to the argument that Classical Chinese Medicine was/is Ecosystem Science. Ecosystem Science (as instantiated by Epidemiology) and Ecosystem Science (as instantiated by Classical Chinese Medicine) share these characteristics: (a) they do not subscribe to the monogenic conception of disease; (b) they involve multi variables; (c) the model of causality presupposed is multi-factorial as well as non-linear.
5,024
Ebola and Localized Blame on Social Media: Analysis of Twitter and Facebook Conversations During the 2014–2015 Ebola Epidemic
This study aimed to analyze main groups accused on social media of causing or spreading the 2014–2016 Ebola epidemic in West Africa. In this analysis, blame is construed as a vehicle of meaning through which the lay public makes sense of an epidemic, and through which certain classes of people become “figures of blame”. Data was collected from Twitter and Facebook using key word extraction, then categorized thematically. Our findings indicate an overall proximate blame tendency: blame was typically cast on “near-by” figures, namely national governments, and less so on “distant” figures, such as generalized figures of otherness (“Africans”, global health authorities, global elites). Our results also suggest an evolution of online blame. In the early stage of the epidemic, blame directed at the affected populations was more prominent. However, during the peak of the outbreak, the increasingly perceived threat of inter-continental spread was accompanied by a progressively proximal blame tendency, directed at figures with whom the social media users had pre-existing biopolitical frustrations. Our study proposes that pro-active and on-going analysis of blame circulating in social media can usefully help to guide communications strategies, making them more responsive to public perceptions.
5,025
Accounting for Contribution of Trade Openness and Foreign Direct Investment in Life Expectancy: The Long-Run and Short-Run Analysis in Pakistan
This paper examines the impact of trade openness and foreign direct investment (FDI) on life expectancy using time series data over the period of 1972–2013. We have applied structural break unit root as well as cointegration tests to examine integrating properties of the variables and cointegration among the variables. The causal linkage between the variables has been tested by applying the VECM Granger causality. The empirical evidence confirms the presence of cointegration amid the variables. Moreover, trade openness and FDI increase population health measured by life expectancy in the long-run. Furthermore, the analysis suggests that trade openness and FDI cause life expectancy in the short-run. These findings have several policy implications to improve life expectancy for the people of Pakistan in particular and other developing countries in general.
5,026
A simplified procedure for the subtractive cDNA cloning of photoassimilate-responding genes: isolation of cDNAs encoding a new class of pathogenesis-related proteins
Transgenic tobacco plants (ppa-1) constitutively expressing Escherichia coli pyrophosphatase behind the 35S CaMV promoter accumulate high levels of soluble sugars in their leaves [27]. These plants were considered a tool to study adaptation of leaves to photoassimilate accumulation at the molecular level. By differential hybridization of a subtractive library enriched for transcripts present in the transgenic plants 12 different cDNAs were isolated. By sequence analysis four cDNAs could be identified as 1-aminocyclopropane-1-carboxylate-oxidase and as three different pathogenesis-related proteins (PR-1b, PR-Q and SAR 8.2). Two cDNAs were homologous to a calmodulin-like protein from Arabidopsis and a human ribosomal protein L19 while six cDNA clones remained unknown. One of these clones (termed PAR-1 for photoassimilate-responsive) displayed features similar to pathogenesis-related proteins: Hybridizing transcripts, 1.2 and 1.0 kb in length, were strongly inducible by salicylate and accumulated in tobacco plants after infection with potato virus Y (PVY) both in infected and uninfected systemic leaves. PAR-1 transcripts also accumulated in wildtype leaves upon floating on glucose and sucrose whereas sorbitol and polyethylene glycol had no effect. Rescreening of the ppa-1 cDNA library with the PAR-1 cDNA as probe resulted in 25 hybridizing cDNAs which by homology were found to fall into three classes (PAR-1a, b, c). The cDNAs coding for PAR-1a and b were 90.6% homologous on the DNA level while both were less related to the PAR-1c cDNA (70.5% and 75.2% homologous, respectively). One open reading frame was identified in all three PAR-1 cDNA classes. Translation would result in proteins with a theoretical molecular mass of about 20 kDa. The N-terminal amino acid sequences resemble a signal peptide which would direct the proteins to the secretory pathway. Using selective 3′ hybridization probes of the three PAR-1 cDNAs it was possible to discriminate the different transcripts. Both PAR-1a and PAR-1c mRNAs are induced in plants treated with PVY.
5,027
Accumulation of noradrenaline and its oxidation products by cultured rodent astrocytes
The accumulation of [(3)H]noradrenaline ([(3)H]NA) and its oxidation products was studied in primary cultures of cerebral astrocytes. Astroglial accumulation of radiolabeled catecholamine ([(3)H] NA and oxidation products) was enhanced by manganese or iron, but it was inhibited by unlabeled NA, dopamine or ascorbate. Tissue:medium ratios of radioactivity increased as extracellular [(3)H]NA was oxidized. When extracellular oxidation was prevented by ascorbate, as confirmed by high performance liquid chromatography with electrochemical detection, either ouabain pretreatment or nominally Na(+)-free incubation medium inhibited approximately one-half of specific [(3)H]NA accumulation by rat (but not mouse) astrocytes. These observations suggest that neurological responses to trace metals and ascorbate may arise from the effects of these agents on the clearance of extracellular catecholamines. Astrocytes can accumulate oxidation products of NA more rapidly than they take up NA itself, but ascorbate at physiological concentrations prevents the oxidation process in extracellular fluid. Furthermore, in the presence of ascorbate, Na(+)-dependent transport mediates a significant component of NA accumulation in rat astrocytes.
5,028
Cloning and Sequence Analysis of the Nucleocapsid Gene of Porcine Epidemic Diarrhea Virus Chinju99
The nucleocapsid (N) gene of the porcine epidemic diarrhea virus (PEDV) Chinju99 which was previously isolated in Chinju, Korea was cloned and sequenced to establish the information for the development of genetically engineered diagnostic reagents. Also, sequences of the nucleotides and deduced amino acids of the Chinju99 N gene were analyzed by alignment with those of CV777 and Br1/87. The nucleotide sequence encoding the entire N gene open reading frame (ORF) of Chinju99 was 1326 bases long and encoded a protein of 441 amino acids with predicted M (r) of 49 kDa. It consisted of 405 adenine (30.5%), 293 cytosine (22.1%), 334 guanines (25.2%) and 294 thymines (22.2%) residues. The Chinju99 N ORF nucleotide sequence was 96.5% and 96.4% homologous with that of the CV777 and Br1/87, respectively. The Chinju99 N protein revealed 96.8% amino acid identity with that of Br1/87 and CV777, respectively. The amino acid sequence contained seven potential sites for threonine (T)- or serine (S)-linked phosphorylation by each protein kinase C and casein kinase II.
5,029
Applications of DNA amplification techniques in veterinary diagnostics
An overview of the principles of the polymerase chain reaction, ligase chain reaction, self-sustained sequence replication and Qβ replicase is given. The application of these methods for the diagnosis of veterinary infectious and hereditary diseases as well as for other diagnostic purposes is discussed and comprehensive tables of reported assays are provided. Specific areas where these DNA-based amplification methods provide substantial advantages over traditional approaches are also highlighted. With regard to PCR-based assays for the detection of viral pathogens, this article is an update of a previous review by Belák and Ballagi-Pordány (1993).
5,030
A/T-rich sequences act as quantitative enhancers of gene expression in transgenic tobacco and potato plants
The role of an A/T-rich positive regulatory region (P268, -444 to -177 from the translation start site) of the pea plastocyanin gene (PetE) promoter has been investigated in transgenic plants containing chimeric promoters fused to the β-glucuronidase (GUS) reporter gene. This region enhanced GUS expression in leaves of transgenic tobacco plants when fused in either orientation to a minimal pea PetE promoter (-176 to +4) and in roots when fused in either orientation upstream or downstream of a minimal cauliflower mosaic virus 35S promoter (-90 to +5). The region was also able to enhance GUS expression in microtubers of transgenic potato plants when placed in either orientation upstream of a minimal class I patatin promoter (-332 to +14). Dissection of P268 revealed that cis elements responsible for enhancing GUS expression from the minimal PetE promoter were distributed throughout P268. Multiple copies of a 31 bp A/T-rich sequence from within P268 and of a 26 bp random A/T sequence were able to enhance GUS expression from the minimal PetE promoter, indicating that A/T-rich sequences are able to act as quantitative, non-tissue-specific enhancer elements in higher plants. Abbreviations: CaMV, cauliflower mosaic virus; GUS, β-glucuronidase; HMG, high-mobility group; MAR, matrix-associated region; MU, methylumbelliferone; SAR, scaffold-associated region.
5,031
Differential expression analysis of the broiler tracheal proteins responsible for the immune response and muscle contraction induced by high concentration of ammonia using iTRAQ-coupled 2D LC-MS/MS
Ammonia has been considered the contaminant primarily responsible for respiratory disease in poultry. Even though it can cause tracheal lesions, its adverse effects on the trachea have not been sufficiently studied. The present study investigated tracheal changes in Arbor Acres broilers (Gallus gallus) induced by high concentration of ammonia using isobaric tag for relative and absolute quantification (iTRAQ)-based proteome analysis. In total, 3,706 proteins within false discovery rate of 1% were identified, including 119 significantly differentially expressed proteins. Functional analysis revealed that proteins related to immune response and muscle contraction were significantly enriched. With respect to the immune response, up-regulated proteins (like FGA) were pro-inflammatory, while down-regulated proteins participated in antigen processing and antigen presenting (like MYO1G), immunoglobulin and cathelicidin production (like fowlicidin-2), and immunodeficiency (like PTPRC). Regarding muscle contraction, all differentially expressed proteins (like TPM1) were up-regulated. An over-expression of mucin, which is a common feature of airway disease, was also observed. Additionally, the transcriptional alterations of 6 selected proteins were analyzed by quantitative RT-PCR. Overall, proteomic changes suggested the onset of airway obstruction and diminished host defense in trachea after ammonia exposure. These results may serve as a valuable reference for future interventions against ammonia toxicity. ELECTRONIC SUPPLEMENTARY MATERIAL: Supplementary material is available for this article at 10.1007/s11427-016-0202-8 and is accessible for authorized users.
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The progress of silver nanoparticles in the antibacterial mechanism, clinical application and cytotoxicity
Nanotechnology is a highly promising field, with nanoparticles produced and utilized in a wide range of commercial products. Silver nanoparticles (AgNPs) has been widely used in clothing, electronics, bio-sensing, the food industry, paints, sunscreens, cosmetics and medical devices, all of which increase human exposure and thus the potential risk related to their short- and long-term toxicity. Many studies indicate that AgNPs are toxic to human health. Interestingly, the majority of these studies focus on the interaction of the nano-silver particle with single cells, indicating that AgNPs have the potential to induce the genes associated with cell cycle progression, DNA damage and mitochondrial associated apoptosis. AgNPs administered through any method were subsequently detected in blood and were found to cause deposition in several organs. There are very few studies in rats and mice involving the in vivo bio-distribution and toxicity, organ accumulation and degradation, and the possible adverse effects and toxicity in vivo are only slowly being recognized. In the present review, we summarize the current data associated with the increased medical usage of nano-silver and its related nano-materials, compare the mechanism of antibiosis and discuss the proper application of nano-silver particles.
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Measuring Access to Continuing Professional Education among the Health Workers in Ghana: Constructing an Index
To measure the levels of access to continuing professional education (CPE) among the health workers, an index (continuing professional education access index: CEAI) was constructed. The CEAI is composed of six indicators: (i) availability of CPE; (ii) distribution of CPE; (iii) informational access; (iv) geographical access; (v) economic access; and (vi) preparedness to release staff. When developing the equation of the CEAI, these six component indicators were weighted in accordance with the order of importance reported by the earlier studies. To test its validity, the CEAI was applied to the CPE status in three regions of Ghana. The results of this application revealed that there was greater discrepancies in the CEAI values according to the type of health facilities. The type of health facilities with the greatest CEAI (= 0.609) implying the best access to CPE was clinics while training/research institutes resulted in the lowest CEAI (= 0.447). Regional variation among the three regions was not significant. A simple linear regression between CEAI and adjusted number of CPE opportunities per health worker produced an extremely high conformity in the model (R (2) = 0.960). This may indicate the validity of the proposed CEAI model to the large extent.
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Industry, innovation and social values
Remaining important tasks in finding and developing new drugs and vaccines for HIV/AIDS, malaria, cancer and other diseases require continued industry research and development. Industry’s research and development pipeline has produced drugs that have saved AIDS victims previously facing certain death, but still no cure nor vaccine is yet available. Experience with the process of research and development indicates that it requires more than a decade of development to produce a new drug with costs in the hundreds of millions of dollars. Intellectual property protection is critically important in assuring that drug development continues. Partnerships between industry and the public sector have increased access to new therapies in developing countries and promise to enhance access to both patented and generic medicines in the future.
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Bioinformatics Analysis of Genes and Pathways of CD11b(+)/Ly6C(intermediate) Macrophages after Renal Ischemia-Reperfusion Injury
Renal ischemia-reperfusion injury (IRI) is a major cause of acute kidney injury (AKI), which could induce the poor prognosis. The purpose of this study was to characterize the molecular mechanism of the functional changes of CDllb+/Ly6C(intermediate) macrophages after renal IRI. The gene expression profiles of CDllb+/Ly6Cintermcdiate macrophages of the sham surgery mice, and the mice 4 h, 24 h and 9 days after renal IRI were downloaded from the Gene Expression Omnibus database. Analysis of mRNA expression profiles was conducted to identify differentially expressed genes (DEGs), biological processes and pathways by the series test of cluster. Protein-protein interaction network was constructed and analysed to discover the key genes. A total of 6738 DEGs were identified and assigned to 20 model profiles. DEGs in profile 13 were one of the predominant expression profiles, which are involved in immune cell chemotaxis and proliferation. Signet analysis showed that Atp5al, Atp5o, Cox4i, Cdc42, Rac2 and Nhp2 were the key genes involved in oxidation-reduction, apoptosis, migration, M1-M2 differentiation, and proliferation of macrophages. RPS18 may be an appreciate reference gene as it was stable in macrophages. The identified DEGs and their enriched pathways investigate factors that may participate in the functional changes of CD 1lb(+)Ly6C(intermediate) macrophages after renal IRI. Moreover, the vital gene Nhp2 may involve the polarization of macrophages, which may be a new target to affect the process of AKI
5,036
s8ORF2 protein of infectious salmon anaemia virus is a RNA-silencing suppressor and interacts with Salmon salar Mov10 (SsMov10) of the host RNAi machinery
The infectious salmon anaemia virus (ISAV) is a piscine virus, a member of Orthomyxoviridae family. It encodes at least 10 proteins from eight negative-strand RNA segments. Since ISAV belongs to the same virus family as Influenza A virus, with similarities in protein functions, they may hence be characterised by analogy. Like NS1 protein of Influenza A virus, s8ORF2 of ISAV is implicated in interferon antagonism and RNA-binding functions. In this study, we investigated the role of s8ORF2 in RNAi suppression in a well-established Agrobacterium transient suppression assay in stably silenced transgenic Nicotiana xanthi. In addition, s8ORF2 was identified as a novel interactor with SsMov10, a key molecule responsible for RISC assembly and maturation in the RNAi pathway. This study thus sheds light on a novel route undertaken by viral proteins in promoting viral growth, using the host RNAi machinery.
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Detection and speciation of common cell culture mycoplasmas by an enzyme-linked immunosorbent assay with biotin-avidin amplification and microporous membrane solid phase
An enzyme-linked immunosorbent assay (ELISA) was developed in order to serve in detecting and speciating mycoplasmas isolated from cell cultures. Its main features included a biotin-streptavidin amplification step and a solid phase consisting of a microporous membrane. Cell samples in the form of suspensions were applied to nitrocellulose or ion exchange membranes immobilized in commerciallyavailable microtiter, multiwell manifolds. The blocking buffer contained 1% purified α-casein. The primary antibodies were monoclonal and the polyclonal secondary antibody was biotinylated. The enzyme utilized was streptavidin-horseradish peroxidase. The substrate-dye complex consisted of either 4-chloro-1-naphthol and hydrogen peroxide or ortho phenylene diamine (OPD) and hydrogen peroxide. The presence of homologous antiserum in the reaction sequence gave clearly visible, colored reactions on the membrane when 50 ul with approximately 10(5) or more cfu/ml were present. This new biotin-avidin microporous membrane (BAMM-ELISA) test can be used both to detect mycoplasmas and to speciate them. The BAMM-ELISA is simple, rapid, sensitive, specific and economical. As such, it has potential for aiding in the control of mycoplasma contamination in cell culture, and could prove useful in clinical diagnostic applications as well.
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RT-ABCDE Strategy for management and prevention of human diseases
In this article, the authors summarized the RT-ABCDE strategy for the management and prevention of human diseases, which includes ReTro—ABCDE (Examination regularity, Disease and risk factor control, Changing lifestyle and reducing pathways of infection and spread, Biochemical and Antagonistic index control and therapeutic treatment as well as RT—Routine and Right Treatment). The RT-ABCDE strategy, a novel concept and an essential method, should be a routine strategy for disease control and prevention. It should be proposed and applied in both clinical and preventive medicine.
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The Modeling of Global Epidemics: Stochastic Dynamics and Predictability
The global spread of emergent diseases is inevitably entangled with the structure of the population flows among different geographical regions. The airline transportation network in particular shrinks the geographical space by reducing travel time between the world's most populated areas and defines the main channels along which emergent diseases will spread. In this paper, we investigate the role of the large-scale properties of the airline transportation network in determining the global propagation pattern of emerging diseases. We put forward a stochastic computational framework for the modeling of the global spreading of infectious diseases that takes advantage of the complete International Air Transport Association 2002 database complemented with census population data. The model is analyzed by using for the first time an information theory approach that allows the quantitative characterization of the heterogeneity level and the predictability of the spreading pattern in presence of stochastic fluctuations. In particular we are able to assess the reliability of numerical forecast with respect to the intrinsic stochastic nature of the disease transmission and travel flows. The epidemic pattern predictability is quantitatively determined and traced back to the occurrence of epidemic pathways defining a backbone of dominant connections for the disease spreading. The presented results provide a general computational framework for the analysis of containment policies and risk forecast of global epidemic outbreaks.
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Adult bacterial nasopharyngitis: A clinical entity?
Objective: To investigate bacterial nasopharyngitis as a cause of adult upper respiratory infection. Design: Prospective case series. Setting: Walk-in medical clinic of a university hospital. Patients: 507 patients with cold or flu symptoms, sore throat, or recent cough; 21 control subjects without symptoms of upper respiratory infection. Measurements and main results: After thorough history and physical examination, the patients underwent nasopharyngeal aspiration and throat culture. Nasopharyngeal specimens were cultured for both bacteria and viruses; antigens for influenza, parainfluenza, and respiratory syncytial virus were sought by enzyme-linked immunosorbent assay (ELISA); serum antibodies to viral respiratory pathogens were determined. Group A beta-hemolytic streptococci grew from the throat specimens of 39 of the 507 patients (8%) or 38 of 3 34 patients (11%) who had clinical diagnoses of pharyngitis. Thirty-three cases of influenza A, 20 cases of influenza B, and seven cases of parainfluenza infections were diagnosed. Bacteria were cultured from the nasopharyngeal secretions of 284 patients (56%). In contrast to pharyngeal culture, commensal mixed flora were rarely found in nasopharyngeal culture. Nasopharyngeal culture of bacteria usually considered to be respiratory pathogens was significantly associated with the presence of leukocytes.Streptococcus pneumoniae (odds ratio 6.0, 95% confidence interval 2.6–14.2),Moraxella catarrbalis (odds ratio 12.9, 95% confidence interval 3.1–79.5), andHemophilus influenzae (odds ratio 3.0, 95% confidence interval 1.2–7.4) were all associated with the presence of leukocytes. In contrast, nasophaiyngeal culture of coagulase-negative staphylococci, mixed flora, and the documentation of a viral infection were not associated with the presence of leukocytes. For none of 21 control subjects were “pathogenic” bacteria found. Conclusions: These data suggest that potentially pathogenic bacteria may have a causal role in adult nasopharyngitis, although further data are needed to confirm this hypothesis.
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Interaction between the learners’ initial grasp of the object of learning and the learning resource afforded
Two studies are reported in this paper. The object of learning in both is the economic principle of changes in price as a function of changes in the relative magnitude of changes in demand and supply. The patterns of variation and invariance, defining the conditions compared were built into pedagogical tools (text, graphs, and worksheets). The first study is the latest in a series of studies aiming to test the fundamental conjecture of the Variation Theory of Learning that new meanings are acquired from experiencing differences against a background of sameness, rather than experiencing sameness against a background of differences. The study compares the learning outcomes under conditions consistent with the basic conjecture with the learning outcomes under conditions not consistent with the theory. The results support the conjecture. The second study shows, however, that the conditions that are consistent with the theory cannot be decided unless the learners’ pre-requisites for the task in question are taken into consideration. One set of the pedagogical tools was found to be highly effective for learners with a better initial grasp of the object of learning, while another set was found to be equally effective for learners with a weaker initial grasp of the object of learning. The two sets were equally ineffective when used for the “wrong” group of learners.
5,042
Viral lower urinary tract infections
Lower urinary tract infections (UTIs) are common among the general population and are most often caused by bacterial pathogens. Viruses are an uncommon cause of UTIs in an immunocompetent host; however, viruses are increasingly recognized as the cause of lower UTI, especially hemorrhagic cystitis, among immunocompromised patients. BK virus, adenovirus, and cytomegalovirus are predominant pathogens involved in hemorrhagic cystitis after stem cell and solid organ transplantation, and their early diagnosis and treatment may prevent significant morbidity of hemorrhagic cystitis. The diagnosis of viral lower UTI is based on molecular techniques, and real-time polymerase chain reaction is often the method of choice because it allows for quantification of viral load. Cidofovir is becoming a drug of choice in viral UTIs because it is active against the most common viral pathogens. This review discusses the epidemiology, pitfalls in diagnosis, and current treatment of viral UTIs.
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High-level Expression of the ORF6 Gene of Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) in Pichia pastoris
High-level expression of the ORF6 gene of porcine reproductive and respiratory syndrome virus (PRRSV) has been proved very difficult. In this work, we cloned and sequenced the ORF6 gene of PRRSV and found that it could not be expressed in Pichia pastoris strain GS115. Then, the ORF6 gene was modified and synthesized based on the codon bias, poly (A) signal of yeast expression system and secondary structure of 5′-end mRNA of foreign gene. The modified gene was inserted into the yeast expression vector pPICZαA, induced and expressed by the same methods. The recombinant protein with a molecular mass of approximately 23 kDa was screened by SDS-PAGE and identified by Western blot with convalescent sera of animals infected with CH-1a strain of PRRSV. The results indicated that it was similar to the native protein. The expression level of the recombinant protein could attain 2.0 g/L. In the meanwhile, the optimal conditions for expression were determined. It provides an additional means for studying the structural and functional characteristics of PRRSV ORF6 gene.
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The bane of “inhumane” weapons and overkill: An overview of increasingly lethal arms and the inadequacy of regulatory controls
Weapons of both defense and offense have grown steadily in their effectiveness—especially since the industrial revolution. The mass destruction of humanity, by parts or in whole, became reality with the advent of toxic agents founded on chemistry and biology or nuclear weapons derived from physics. The military’s new non-combat roles, combined with a quest for non-lethal weapons, may change the picture in regard to conventional defense establishments but are unlikely to deter bellicose tyrants or the new terrorists from using the unlimited potential of today’s and tomorrow’s arsenals. The author addresses the issues that are raised by this developing situation with the intent of seeking those ethics that will enable us to survive in a future and uncertain world.
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Role of microbiota on lung homeostasis and diseases
The lungs, as a place of gas exchange, are continuously exposed to environmental stimuli, such as allergens, microbes, and pollutants. The development of the culture-independent technique for microbiological analysis, such as 16S rRNA sequencing, has uncovered that the lungs are not sterile and, in fact, colonized by diverse communities of microbiota. The function of intestinal microbiota in modulating mucosal homeostasis and defense has been widely studied; however, the potential function of lung microbiota in regulating immunity and homeostasis has just begun. Increasing evidence indicates the relevance of microbiota to lung homeostasis and disease. In this review, we describe the distribution and composition of microbiota in the respiratory system and discuss the potential function of lung microbiota in both health and acute/chronic lung disease. In addition, we also discuss the recent understanding of the gut-lung axis, because several studies have revealed that the immunological interaction among the gut, the lung, and the microbiota was involved in this issue.
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Infective viruses produced from full-length complementary DNA of swine vesicular disease viruses HK/70 strain
The full-length cDNA clone of swine vesicular disease virus HK/70 strain named pSVOK(12) was constructed in order to study the antigenicity, replication, maturation and pathogenicity of swine vesicular disease virus. In vitro transcription RNA from pSVOK(12) transfected IBRS-2 cells and the recovered virus RNA were isolated and sequenced, then indirect hemagglutination test, indirect immunofluorescence assays, eleectron microscope test, 50% tissue culture infecting dose (TCID(50)) assays and mouse virulence studies were performed to study the antigenicity and virulence of the recovered virus. The result showed that the infectious clones we obtained and the virus derived from pSVOK(12) had the same biological properties as the parental strain HK/70. The full-length infectious cDNA clone, pSVOK(12), will be very useful in studies of the antigenicity, virulence, pathogenesis, maturation and replication of SVDV.
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Monolayer culture of rat parotid acinar cells without basement membrane substrates
Acinar cells have been difficult to maintain in primary or secondary cultures over extended periods of time. The most successful monolayer culture system reported to date requires basement membrane substrates. We report here a technique for culture of rat parotid acinar cells which does not rely upon basement membrane supports for maintenance and growth. The procedure involves gland excision, treatment to chelate metal ions, enzymatic digestion with collagenases and hyaluronidase, removal of fat and red blood cells by gravimetric separation, and nylon mesh filtration to yield a homogeneous suspension of small aggregates and single cells. The cells were examined for: a) morphology, identity, and growth; b) macromolecular synthesis; and c) secretory output. They were healthy, peroxidase positive, and growing for up to 10 d. Protein synthesis increased from the point of cell layer formation at 3 to 4 d, through 10 d, while DNA synthesis decreased. As in other studies, amylase secretion fell sharply between 2 and 4 d in culture and remained low. Although previous studies indicated that the initial isolation protocol left these acinar cells unable to thrive in monolayer culture except in the presence of basement membrane substrates, the modified technique reported herein allows these cells to attach, spread, and grow on a wide variety of commerically available plasticware. this method lends itself readily to long-term analysis of rat parotid acinar cell metabolism without the complications of dedifferentiation, cell loss through culture manipulation common in suspension cultures, or complex interactions between bioactive supports and cell surfaces.
5,048
Expatriates: Special Considerations in Pretravel Preparation
Expatriates comprise a diverse set of travelers who face unique medical, psychiatric, and non-health-related risks as a result of increased exposure to host country environment and associated lifestyle. Expatriates have an increased risk of developing malaria, gastrointestinal disorders, latent tuberculosis, vaccine-preventable infections, and psychological disorders, when compared with other travelers, yet the majority of existing pretravel guidelines have been designed to suit the needs of nonexpatriates. Although greater interest in expatriate health issues has led to improved characterization of illness in this population, expatriate-specific risk mitigation strategies—including modifications to chemoprophylaxis recommendations, limiting tuberculosis exposure, and prevention of occupational or sexual blood-borne virus transmission—are poorly described. Occupations and destinations affect travel-related disease risk and should inform the pretravel consultation.
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Ziziphus mucronata: an underutilized traditional medicinal plant in Africa
In Africa, rural people depend heavily, if not exclusively, on medicinal plants and indigenous healthcare knowledge to meet their medical needs. Over 80000 flowering plant species are used medicinally worldwide. Amongst them are the underutilized Ziziphus species in the Rhamnaceae family. In terms of abundance and economic value, Z. jujuba and Z. mauritiana are currently the most important, especially in China and India where they are cultivated and exploited for medicinal use and their edible fruits. We examined a related common species widely distributed in Africa, Z. mucronata, whose economic value has not, as yet, been explored. Local people in various African countries use its different parts to cure a large number of diseases, many of which are similar to those treated with Z. jujuba and Z. mauritiana. Several studies have shown that Z. mucronata has cyclopeptide alkaloids, i.e., mucronines F, G and H, with antibacterial properties. Conservation strategies to sustain and maximize the benefits of Z. mucronata to people are proposed.
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Feline Immunodeficiency Virus and Puma Lentivirus in Florida panthers (Puma concolor coryi): Epidemiology and Diagnostic Issues
This study documents the seroprevalence of feline immunodeficiency virus (FIV) and puma lentivirus (PLV) in free-ranging and captive Florida panthers (Puma concolor coryi) (n = 51) and translocated Texas cougars (P. concolor stanleyana) (n = 10) from 1985 to 1998. The sera were tested for anti-FIV antibodies by enzyme-linked immunosorbent assay (ELISA) and Western blot tests. The ELISAs were read kinetically (KELA) and the sera were retrospectively examined by PLV peptide ELISA. Eleven panthers and one cougar were positive by KELA; 4 panthers and 4 cougars were equivocal; 35 panthers and 5 cougars were negative; and 1 panther had no data. Seven of the 11 KELA-positive panthers were also positive by Western blot tests and all but one were positive by PLV peptide ELISA. Ten KELA-negative and Western blot-negative cats, were positive by PLV peptide ELISA. KELA results varied within cats from one sample period to the next, but PLV peptide ELISA results were consistent. Territorial sympatry and mating behaviour, noted from radiotelemetry location data on the cats, may have contributed to viral transmission between seropositive animals. These findings suggest that Florida panthers and the introduced Texas cougars have been exposed to FIV and/or PLV.
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Generation of antibody- and B cell-deficient pigs by targeted disruption of the J-region gene segment of the heavy chain locus
A poly(A)-trap gene targeting strategy was used to disrupt the single functional heavy chain (HC) joining region (J(H)) of swine in primary fibroblasts. Genetically modified piglets were then generated via somatic cell nuclear transfer (SCNT) and bred to yield litters comprising J(H) wild-type littermate (+/+), J(H) heterozygous knockout (±) and J(H) homozygous knockout (−/−) piglets in the expected Mendelian ratio of 1:2:1. There are only two other targeted loci previously published in swine, and this is the first successful poly(A)-trap strategy ever published in a livestock species. In either blood or secondary lymphoid tissues, flow cytometry, RT-PCR and ELISA detected no circulating IgM(+) B cells, and no transcription or secretion of immunoglobulin (Ig) isotypes, respectively in J(H) −/− pigs. Histochemical and immunohistochemical (IHC) studies failed to detect lymph node (LN) follicles or CD79α(+) B cells, respectively in J(H) −/− pigs. T cell receptor (TCR)(β) transcription and T cells were detected in J(H) −/− pigs. When reared conventionally, J(H) −/− pigs succumbed to bacterial infections after weaning. These antibody (Ab)- and B cell-deficient pigs have significant value as models for both veterinary and human research to discriminate cellular and humoral protective immunity to infectious agents. Thus, these pigs may aid in vaccine development for infectious agents such as the pandemic porcine reproductive and respiratory syndrome virus (PRRSV) and H1N1 swine flu. These pigs are also a first significant step towards generating a pig that expresses fully human, antigen-specific polyclonal Ab to target numerous incurable infectious diseases with high unmet clinical need.
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L3T4(CD4)-, Lyt-2(CD8)- and Mac-1(CD11b)-phenotypic leukocytes in murine cryptococcal meningoencephalitis
An immunohistological study of L3T4(CD4)+ and LYT-2(CD8)+ lymphocytes, Mac-1(CD11b)+ monocytes and granulocytes in experimental murine cryptococcal meningoencephalitis was conducted. To assess the concomitant inflammatory reaction in an extracerebral site, livers were examined in parallel. Mice were infected i.v. withCryptococcus neoformans, group A/D, and organs were examined immunohistologically for CD4-, CD8- and monocyteand granulocyte-specific CD11b-phenotypic leukocytes over a period of 60 days. Intracerebrally, agglomerations of cryptococci formed pseudocysts that were surrounded by CD4+ and CD8+ lymphocytes at the end of the second week post-infection, followed by the invasion of monocytes and granulocytes into the lesions. After the fourth week post-infection, most of the invaded lesions were transformed into glious scars. Meningitis was usually marked and showed a homogenous distribution of CD4-, CD8- and CD11b-phenotypic cells, with a predominance of monocytes and CD4+ lymphocytes. Inflammatory infiltrates in the liver were found already 4 days post-infection. CD4+ lymphocytes and monocytes were distributed homogenously in the infiltrates, with a lower number of CD8+ lymphocytes being located rather in the periphery of the infiltrates. Comparing leukocyte kinetics in brain and liver, an important observation was the delayed immigration of immune cells at the intracerebral cryptococcal lesions as compared with the liver, and the different migration patterns of T-lymphocyte subgroups and macrophages. These results suggest that there are differential leukocyte migration patterns in the liver and brain following disseminated cryptococcosis. The immunological aspects of the observed leukocyte kinetics are discussed.
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Acidification and endosome-like compartments in the presynaptic terminals of frog retinal photoreceptors
By using the ‘acidotropic’ vital dye, Acridine Orange, we have found that the presynaptic terminals of rod and cone photoreceptors in retinas ofRana pipiens maintain a low pH relative to the surrounding medium through an energy dependent mechanism. When this pH is raised, by exposing the retinas to weak bases like ammonium chloride, the terminals exhibit large, membrane-delimited compartments, many of which accumulate endocytic tracers. This effect is partly reversed when the weak bases are removed. We infer that among the acidified structures within the terminals are endocytic compartments with at least some of the characteristics of the endosomes that participate in receptor-mediated endocytosis in other cell types. One role of these structures in the terminals may be in the recycling of synaptic vesicles.
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Rationality of 17 cities’ public perception of SARS and predictive model of psychological behavior
This study investigated the feature of Chinese peoples’ perception of SARS by surveying a stratified sample of 4231 people from 17 cities in China, and primarily proposed a risk perception centered predictive model of psychological behavior in crisis. The results indicated that, negative SARS-related information, especially information of personal interest, will arouse people’s risk perception of high level, and lead to irrational nervousness or scare; but positive SARS-related information, including recovery information and that with measures taken by government, can decrease the level of risk perception. In the middle of May, people felt the highest level of risk on the SARS pathogens; the following are the physical health condition and infectivity after recovering from SARS; they are factors that need special attention. SEM result analyses supported our hypotheses in that SARS-related information affect people’s coping behavior and mental health through their risk perception, the four indices of risk assessment, feeling of nervousness, coping behavior and mental health are effective presentimental indices for public psychological behavior in risky events.
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Ascorbic acid transport in mouse and rat astrocytes is reversibly inhibited by furosemide, SITS, and DIDS
The uptake ofL-ascorbic acid (vitamin C) by astrocytes was studied using primary cultures prepared from the neopallium of newborn Swiss CD-1 mice or Sprague-Dawley rats. Initial uptake rates were significantly greater in mouse than in rat astrocytes. Exposure of cultures to 0.25 mM dibutyryl cyclic AMP for 2 weeks changed cell morphology from polygonal to stellate and stimulated ascorbate uptake, with the greatest stimulation occurring in mouse astrocytes. Uptake was specific for the vitamin since it was not diminished by the presence of other organic anions including acetate, formate, lactate, malonate, oxalate, p-aminohippurate, pyruvate and succinate. Ascorbate uptake was Na(+)-dependent but did not have a specific requirement for external Cl(−) (Cl(−) (0)). Substitution of Cl(−) (0) by Br(−) or NO(3) (−) decreased ascorbate uptake rates by 20–31%; whereas substitution by gluconate or isethionate increased uptake by 20–31%. Ascorbate transport by astroglial cultures from both animal species was rapidly (≤1 min) and reversibly inhibited by the anion transport inhibitors furosemide, 4-acetamido-4′-isothiocyanostilbene-2,2′-disulfonic acid (SITS) and 4,4′-diisothiocyanostilbene-2,2′-disulfonic acid (DIDS). The rapid and reversible effects of the impermeant inhibitors (SITS and DIDS) are consistent with direct inhibition of ascorbate transporters located in the astroglial plasma membrane.
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On the Use of Post-Transcriptional Processing Elements in Transgenes
RNA processing events modulate final productivity of a given transgene. We have evaluated a series of RNA elements for their ability to enhance α1-antitrypsin production in mammary cells. Our results indicate the need for a case-by-case assessment of each construct design and the occurrence of gene silencing events in vivo.
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Evidence for electrogenic sodium-dependent ascorbate transport in rat astroglia
The dependence of ascorbate uptake on external cations was studied in primary cultures of rat cerebral astrocytes. Initial rates of ascorbate uptake were diminished by lowering the external concentrations of either Ca(2+) or Na(+). The Na(+)-dependence of astroglial ascorbate uptake gave Hill coefficients of approximately 2, consistent with a Na(+)-ascorbate cotransport system having stoichiometry of 2 Na(+)∶1 ascorbate anion. Raising external K(+) concentration incrementally from 5.4 to 100 mM, so as to depolarize the plasma membrane, decreased the initial rate of ascorbate uptake, with the degree of inhibition depending on the level of K(+). The depolarizing ionophores gramicidin and nystatin slowed ascorbate uptake by astrocytes incubated in 5.4 mM K(+); whereas, the nondepolarizing ionophore valinomycin did not. Qualitatively similar results were obtained whether or not astrocytes were pretreated with dibutyryl cyclic AMP (0.25 mM for 2 weeks) to induce stellation. These data are consistent with the existence of an electrogenic Na(+)-ascorbate cotransport system through which the rate of ascorbate uptake is modulated by endogenous agents, such as K(+), that alter astroglial membrane potential.
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The Social Indicators Movement: Progress, Paradigms, Puzzles, Promise and Potential Research Directions
This paper is a response to the article entitled “Fifty years after the Social Indicators Movement: Has the promise been fulfilled?” by Ken Land and Alex Michalos (2015) which constitutes a careful review of the historical development of the Social Indicators Movement, utility of social indicators in shaping the concept of quality of life and subjective well-being, and issues deserving social indicators research in future. In this response paper, we join in the discussion by highlighting five issues—progress, paradigms, puzzles, promise, and potential research directions of social indicators research. In terms of progress, while we have accomplished many tasks proposed by Solomon et al. (The quality of life, Sage, London 1980), some of them are yet to be achieved. Regarding research paradigms surrounding social indicators, researchers have primarily used positivistic or post-positivistic orientation to conduct and interpret social indicators research, with relatively fewer studies using interpretive, constructionist or critical theory perspective. There are also several puzzles deserving consideration. These include (a) the use of “other types of evidence”, particularly qualitative data; (b) evaluation of social programs; (c) feasibility of assessing “social progress”; (d) choice of social indicators; (e) interpretation of findings; (f) methodological debates; and (g) explanations for social change. Finally, the promise of social indicators research to promote quality of life and potential future research directions of social indicators research are discussed.
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Genome sequencing and phylogenetic analysis of Banna virus (genus Seadornavirus, family Reoviridae) isolated from Culicoides
In an investigation of blood-sucking insects and arboviruses, a virus (YN12243) was isolated from Culicoides samples collected in the Sino-Burmese border region of Yunnan Province, China. The virus caused cytopathic effect (CPE) in C6/36 cells and passaged stably. Polyacrylamide gel analysis showed that the genome of YN12243 was composed of 12 segments of double-stranded RNA (dsRNA), with a distribution pattern of 6-6. The nucleotide and amino acid sequences of the coding region (1‒12 segments) were 17,803 bp and 5,925 amino acids in length, respectively. The phylogenetic analysis of VP1 protein (RdRp) revealed that YN12243 belonged to genus Seadornavirus of family Reoviridae, and further analysis indicated that YN12243 belongs to the Banna virus (BAV) genotype A2. Additionally, YN12243 was located in the same evolutionary cluster as BAV strains isolated from different mosquito species, suggesting that the BAV isolated from Culicoides does not have species barriers. These results indicate that Culicoides can also be a vector for BAV. In view of the hematophagous habits of Culicoides on cattle, horses, deer, and other large animals, as well as the possibility of spreading and causing a variety of animal arboviral diseases, it is important to improve infection detection and monitor the BAV in large livestock.
5,060
Clinical and Pathological Studies in Cattle with Hepatic Disease
West, H.J., 1997. Clinical and pathological studies in cattle with hepatic disease. Veterinary Research Communications, 21 (3), 169-185 In cattle with hepatic lipidosis, hepatic abscessation, leptospirosis, biliary calculi or fasciolosis, the progression of the disease was studied by serial measurements of serum total bile acid concentrations, plasma glutamate dehydrogenase, γ-glutamyltranserase, 5′-nucleotidase and leucine aminopeptidase activities Terminalia avicennioides and by liver biopsy. Regardless of the cause of the hepatic disease, weight loss, anorexia, dullness and depression were consistent features. Signs of hepatic encephalopathy, such as blindness, head pressing, excitability, ataxia and weakness were less common and, together with pyrexia and jaundice, were grave prognostic signs. Plasma ammonia concentrations were significantly elevated compared to clinically normal cattle, but such changes were not always accompanied by a decline in plasma urea concentrations. In normal, healthy cattle, the plasma ammonia:urea concentration ratio is 9:1 and the plasma ammonia:glucose concentration is 11:1. In hepatic disease, a plasma ammonia:glucose ratio >40:1 or plasma ammonia:urea ratio >30:1, particularly with a rising total ketone body concentration and a declining glucose concentration, carried a guarded prognosis. The study suggested that other factors, such as hypokalaemia, alkalosis, short-chain volatile fatty acids, and false and true neuro-transmitters, may be important in the pathogenesis of hepatic coma in cattle.
5,061
Translational Control of the Picornavirus Phenotype
Picornaviruses are small animal viruses with positive-strand genomic RNA, which is translated using cap-independent internal translation initiation. The key role in this is played by ciselements of the 5"-untranslated region (5"-UTR) and, in particular, by the internal ribosome entry site (IRES). The function of translational ciselements requires both canonical translation initiation factors (eIFs) and additional IRES trans-acting factors (ITAFs). All known ITAFs are cell RNA-binding proteins which play a variety of functions in noninfected cells. Specific features of translational ciselements substantially affect the phenotype and, in particular, tissue tropism and pathogenic properties of picornaviruses. It is clear that, in some cases, the molecular mechanism involved is a change in interactions between viral ciselements and ITAFs. The properties and tissue distribution of ITAFs may determine the biological properties of other viruses that also use the IRES-dependent translation initiation. Since this mechanism is also involved in translation of several cell mRNAs, ITAF may contribute to the regulation of the most important aspects of the living activity in noninfected cells.
5,062
Insect-transmitted vertebrate viruses: Flaviviridae
The Flaviviridae include almost 70 viruses, nearly half of which have been associated with human disease. These viruses are among the most important arthropod-borne viruses worldwide and include dengue, yellow fever, and Japanese encephalitis viruses. Morbidity and mortality caused by these viruses vary, but collectively they account for millions of encephalitis, hemorrhagic fever, arthralgia, rash, and fever cases per year. Most of the members of this family are transmitted between vertebrate hosts by arthropod vectors, most commonly mosquitoes or ticks. Transmission cycles can be simple or complex depending on the hosts, vectors, the virus, and the environmental factors affecting both hosts and viruses. Replication of virus in invertebrate hosts does not seem to result in any significant pathology, which suggests a close evolutionary relationship between virus and vector. Another example of this relationship is the ability of these viruses to grow in invertebrate cell culture, where replication usually results in a steady state, persistent infection, often without cytopathic effect. Yields of virus from insect cell culture vary but are generally similar to yields in vertebrate cells. Replication kinetics are comparable between insect and vertebrate cell lines, despite differences in incubation temperature. Both vertebrate and insect cell culture systems continue to play a significant role in flavivirus isolation and the diagnosis of disease caused by these agents. Additionally, these culture systems permit the study of flavivirus attachment, penetration, replication, and release from cells and have been instrumental in the production and characterization of live-attenuated vaccines. Both vertebrate and insect cell culture systems will continue to play a significant role in basic and applied flavivirus research in the future.
5,063
Learning Theory as Teaching Resource: Enhancing Students’ Understanding of Economic Concepts
A group of experienced secondary school teachers used a novel learning theory as a resource for planning and carrying out their teaching of a difficult economic concept. Their students’ mastery of this concept after a series of three lessons was compared with the mastery of the same concept by students who were taught by another group of teachers under the same conditions except for the use of the theory. The difference in learning outcomes was extreme. Observations of what was happening in the classrooms showed subtle but decisive differences correlated with the differences in outcome. These differences were interpreted in terms of the theory used by the first group, and the results seem to give support to the theoretical claim that for any specific object of learning there is a necessary pattern of variation and invariance that the learners must experience in order to appropriate the object of learning in question and thus by bringing out that pattern in the learning situation, the likelihood of that object of learning being appropriated is enhanced. Furthermore, this study shows how the understanding of the simultaneous change in the supply of and the demand for a certain good affects its market price can be brought about in a powerful way.
5,064
Modeling Nosocomial Transmission of Rotavirus in Pediatric Wards
Nosocomial transmission of viral and bacterial infections is a major problem worldwide, affecting millions of patients (and causing hundreds of thousands of deaths) per year. Rotavirus infections affect most children worldwide at least once before age five. We present here deterministic and stochastic models for the transmission of rotavirus in a pediatric hospital ward and draw on published data to compare the efficacy of several possible control measures in reducing the number of infections during a 90-day outbreak, including cohorting, changes in healthcare worker-patient ratio, improving compliance with preventive hygiene measures, and vaccination. Although recently approved vaccines have potential to curtail most nosocomial rotavirus transmission in the future, even short-term improvement in preventive hygiene compliance following contact with symptomatic patients may significantly limit transmission as well, and remains an important control measure, especially where resources are limited.
5,065
Staged progression model for epidemic spread on homogeneous and heterogeneous networks
In this paper, epidemic spread with the staged progression model on homogeneous and heterogeneous networks is studied. First, the epidemic threshold of the simple staged progression model is given. Then the staged progression model with birth and death is also considered. The case where infectivity is a nonlinear function of the nodes’ degree is discussed, too. Finally, the analytical results are verified by numerical simulations.
5,066
Inhibitory effects of human cystatin C on plum pox potyvirus proteases
The effect of different protease inhibitors on the proteolytic processing of the plum pox potyvirus (PPV) polyprotein has been analyzed. Human cystatin C, an inhibitor of cysteine proteases, interfered with the outoprocessing of the viral papain-like cysteine protease HCPro. Unexpectedly, it also had an inhibitory effect on the autocatalytic cleavage of the Nla protease which, although it has a Cys residue in its active center, has been described as structurally related to serine proteases. Other protease inhibitors tested had no effect on any of the cleavage events analyzed.
5,067
Molecular cloning and sequence comparison of the S1 glycoprotein of the Gray and JMK strains of avian infectious bronchitis virus
The nucleotide sequences of S1 glycoprotein genes of the Gray and JMK strains of avian infectious bronchitis virus (IBV) were determined and compared with published sequences for IBV. The IBV Gray and JMK strains had 99% nucleotide sequence similarity. The overall nucleotide sequence similarity of the Gray and JMK strains compared with other IBV strains was between 82.0% and 87.4%. The similarity of the predicted amino acid sequence for the S1 glycoproteins of the Gray and JMK strains was 98.8%. Six of the 10 differences in the amino acid sequence were found between residues 99 and 127, suggesting a possible role for that region in the tissue trophisms of the viruses. The S1 glycoprotein of the Gray and JMK strains had 79.5%–84.6% amino acid similarity with the published sequence of other IBV strains. Serine instead of phenylalanine was observed in the protease cleavage site between the S1 and S2 glycoprotein subunits for the Gray and JMK strains, which was similar to the published sequence for the Ark99 and SE17 strains. The significance of that amino acid change is not known. Based on the nucleotide sequence of the Gray and JMK strains, theBsmAI restriction enzyme was selected by computer analysis and was used in restriction fragment length polymorphism analysis to differentiate the two strains.
5,068
Genetic characterization of an isolate of canine distemper virus from a Tibetan Mastiff in China
Canine distemper (CD) is a highly contagious, often fatal, multisystemic, and incurable disease in dogs and other carnivores, which is caused by canine distemper virus (CDV). Although vaccines have been used as the principal means of controlling the disease, CD has been reported in vaccinated animals. The hemoagglutinin (H) protein is one of the most important antigens for inducing protective immunity against CD, and antigenic variation of recent CDV strains may explain vaccination failure. In this study, a new CDV isolate (TM-CC) was obtained from a Tibetan Mastiff that died of distemper, and its genome was characterized. Phylogenetic analysis of the H gene revealed that the CDV-TM-CC strain is unique among 20 other CDV strains and can be classified into the Asia-1 group with the Chinese strains, Hebei and HLJ1-06, and the Japanese strain, CYN07-hV. The H gene of CDV-TM-CC shows low identity (90.4 % nt and 88.9 % aa) with the H gene of the classical Onderstepoort vaccine strain, which may explain the inability of the Tibetan Mastiff to mount a protective immune response. We also performed a comprehensive phylogenetic analysis of the N, P, and F protein sequences, as well as potential N-glycosylation sites and cysteine residues. This analysis shows that an N-glycosylation site at aa 108-110 within the F protein of CDV-TM-CC is specific for the wild-type strains (5804P, A75/17, and 164071) and the Asia-1 group strains, and may be another important factor for the poor immune response. These results provide important information for the design of CD vaccines in the China region and elsewhere.
5,069
Sequence determination of the extreme 5′ end of equine arteritis virus leader region
The extreme 5′ end of the leader sequence of four equine arteritis virus (EAV) strains was obtained by using rapid amplification of cDNA end method (5′ RACE), and sequenced. Seventeen more nucleotides were added upstream of the 5′ end of the EAV published genomic sequence. A common feature among the analyzed EAV isolates was the presence of an AUG start codon within the added sequence and the appearance of an intraleader open reading frame (ORF) of 111 nucleotides which was predicted to encode a peptide of 37 amino acids. The role of this putative intraleader ORF has yet to be determined.
5,070
State substance abuse and mental health managed care evaluation program
The articles in this special section of the Journal of Behavioral Health Services & Research (30:1) present results from evaluations of publicly funded managed care initiatives for substance abuse and mental health treatment in Arizona, Iowa, Maryland, and Nebraska. This overview outlines the four managed care programs and summarizes the results from the studies. The evaluations used administrative data and suggest a continuing challenge to structure plans so that undesired deleterious effects associated with adverse selection are minimized. Successful plans balanced risk with limited revenues so that they permitted greater access to less intensive services. Shifts from inpatient services to outpatient care were noted in most states. Future evaluations might conduct patient interviews to examine the effectiveness and quality of services for mental health and substance abuse problems more closely.
5,071
Modifications of lysosomal enzymes in Dictyostelium discoideum
This paper has two purposes. The first is to review the past studies on the structure, biosynthesis, and immunological properties of a class of glycoproteins, the lysosomal enzymes, in Dictyostelium discoideum. The second purpose is to present new data on the analysis of mutant strains altered in the biosynthesis of the lipid-linked precursor of N-linked oligosaccharides, and on the characterization of new carbohydrate antigenic determinants found on multiple proteins in Dictyostelium. We will also show how a combination of genetic, biochemical and immunochemical approaches have been used to unravel a portion of the glycosylation pathway in Dictyostelium. The long-term goal of these studies is to use Dictyostelium discoideum as a model system to understand the functions of a variety of glycoconjugates in a multicellular organism. The existence of a large number of mutant strains which are altered in a variety of cellular functions, development and the posttranslational modification of multiple proteins, offers a great opportunity to explore this area.
5,072
New quality and quantity indices in science (NewQIS): results of the first decade—project progress review
Strategies employing information science and scientometric approaches were introduced to science policy and management over the past decades. As a rapidly evolving field, new bibliometric parameters are proposed and discussed continuously and the fields also benefits from the introduction of novel visualization techniques. The present article summarizes the experiences with a platform that combines geographical mapping with scientometrics. It was established between 2005 and 2008 at the Charité in Berlin and termed “New Quality and Quantity Indices in Science” (NewQIS), consisting of the integration of common scientometric parameters such as the h-index and novel visualization techniques including density equalizing mapping. NewQIS was used to assess socio-economic important fields of medicine and sciences. Within NewQIS studies, research activities, citation patterns and their relation to socio-economic figures were analyzed with regard to time periods, countries, continents or even single cities. Within the decade after its establishment, more than 80 NewQIS articles were peer-reviewed and published. Being a non-funded low budget project, it was used by many medical students to conduct their MD thesis. The narrow technical frame led to the chance of a comparison of research output between different fields of science. This article summarizes NewQIS 1.0 activities, discusses its limits and gives a look into the future of NewQIS 2.0 with a target of 200 evaluated entities of the biomedical field of sciences.
5,073
Modeling Importations and Exportations of Infectious Diseases via Travelers
This paper is an attempt to estimate the risk of infection importation and exportation by travelers. Two countries are considered: one disease-free country and one visited or source country with a running endemic or epidemic infectious disease. Two models are considered. In the first model (disease importation), susceptible individuals travel from their disease-free home country to the endemic country and come back after some weeks. The risk of infection spreading in their home country is then estimated supposing the visitors are submitted to the same force of infection as the local population but do not contribute to it. In the second model (disease exportation), it is calculated the probability that an individual from the endemic (or epidemic) country travels to a disease-free country in the condition of latent infected and eventually introduces the infection there. The input of both models is the force of infection at the visited/source country, assumed known. The models are deterministic, but a preliminary stochastic formulation is presented as an appendix. The models are exemplified with two distinct real situations: the risk of dengue importation from Thailand to Europe and the risk of Ebola exportation from Liberia to the USA.
5,074
Demyelination in canine distemper encephalomyelitis: An ultrastructural analysis
A morphological study of selected white matter lesions was carried out in three dogs with canine distemper encephalomyelitis. Two dogs had experimental infections while the third was a spontaneous case. Two stages were identified in the process of demyelination. The earliest evidence of myelin injury was a ballooning change in myelin sheaths involving single or multiple axons. This was followed by a progressive stripping of compact sheaths by the cytoplasmic fingers of phagocytic cells which infiltrated and removed myelin lamellae. Some axonal necrosis also accompanied these changes. Where demyelination occurred, canine distemper viral nucleocapsids were found in astrocytes, macrophages, ependymal cells and infiltrating lymphocytes. In contrast, oligodendrocytes were conspicuous by their apparent lack of infection. Thus it seems that myelin loss cannot be ascribed to oligodendrocyte infection. Perturbed astrocyte function following canine distemper viral infection may cause oedema of myelin sheaths, leading to ballooning and primary demyelination. Cells which phagocytosed myelin were mainly identified as microglial cells with lesser involvement by astrocytes. Rarely, oligodendrocytes also acted as macrophages. Myelin debris was engulfed in bulk or as small droplets into coated pits. Remyelination was present in established plaques although not in great abundance, perhaps due to the diminished oligodendrocyte numbers and a relative increase in immature forms of these cells. These observations are compared to similar changes observed in other demyelinating diseases of animals and man.
5,075
A rational approach to selective pharmacophore designing: an innovative strategy for specific recognition of Gsk3β
We propose a novel cheminformatics approach that combines structure and ligand-based design to identify target-specific pharmacophores with well-defined exclusion ability. Our strategy includes the prediction of selective interactions, developing structure, and knowledge-based selective pharmacophore models, followed by database screening and molecular docking. This unique strategy was employed in addressing the off-target toxicity of Gsk3β and CDKs. The connections of Gsk3β in eukaryotic cell apoptosis and the extensive potency of Gsk3β inhibitors to block cell death have made it a potential drug-discovery target for many grievous human disorders. Gsk3β is phylogenetically very closely related to the CDKs, such as CDK1 and CDK2, which are suggested to be the off-target proteins of Gsk3β inhibitors. Here, we have employed novel computational approaches in designing the ligand candidates that are potentially inhibitory against Gsk3β, with well-defined the exclusion ability to CDKs. A structure-ligand -based selective pharmacophore was modeled. This model was used to retrieve molecules from the zinc database. The hits retrieved were further screened by molecular docking and protein–ligand interaction fingerprints. Based on these results, four molecules were predicted as selective Gsk3β antagonists. It is anticipated that this unique approach can be extended to investigate any protein–ligand specificity.
5,076
Nanotechnology for the Food and Bioprocessing Industries
Several complex set of engineering and scientific challenges in the food and bioprocessing industries for manufacturing high quality and safe food through efficient and sustainable means can be solved through nanotechnology. Bacteria identification and food quality monitoring using biosensors; intelligent, active, and smart food packaging systems; and nanoencapsulation of bioactive food compounds are few examples of emerging applications of nanotechnology for the food industry. We review the background about the potential of nanotechnology, provide an overview of the current and future applications of nanotechnology relevant to food and bioprocessing industry, and identify the societal implications for successful implementation of nanotechnology.
5,077
Serum IgG, blood profiles, growth and survival in goat kids supplemented with artificial colostrum on the first day of life
The objective of this study was to compare serum IgG concentrations, blood metabolites indicative of nutritional status, weight gain and mortality rate in goat kids fed a commercial colostral supplement containing immunoglobulins against several pathogen microorganisms, prior to the ingestion of the mother colostrum, and goat kids ingesting natural colostrum only. There was no difference in serum IgG concentrations between 27 kids fed a colostrum supplement (20 g, derived from cow lacteal secretions) prior to the kids’ first meal (658 ± 703 mg dl(−1)) and 21 kids ingesting maternal colostrum freely (1011 ± 1140 mg dl(−1)) at 24 hours of birth. Hematocrit values, serum glucose and urea concentrations at 24 hours and 5 days of age were unaffected by treatment. Serum total proteins were 14% higher (P < 0.05) in the unsuplemented group than in the supplemented group at 5 d of age. There was no significant difference between the supplemented and unsupplemented kids in daily weight gain from birth to 70 days of age (92 ± 4.8 vs 102 ± 5.1 g day(−1)). Mortality was 4% for kids receiving the colostrum supplement as compared with 0.0% for kids ingesting maternal colostrum only. Results suggest that, in intensively managed non-dairy goats with kiddings in summer, the supplementation of this commercial colostrum derived from cow lacteal secretions and containing antibodies against diverse pathogens organisms did not enhanced growth, survival or immunity under the farming conditions of this study.
5,078
Cutaneous Phaeohyphomycosis Caused by Exophiala attenuata in a Domestic Cat
A 7-year-old female-spayed, domestic short-haired cat was presented to her veterinarian with a mass on the hind paw. Histopathologic examination of a tissue biopsy revealed nodular pyogranulomatous panniculitis with intralesional pigmented fungal hyphae. A dematiaceous fungal isolate was isolated with a micromorphological phenotype consistent with the anamorphic genus Exophiala: budding cells, torulose mycelium and annellidic conidiogenesis from simple conidiophores consisting of terminal and lateral cells that tapered to a short beak at the apex. Sequence homology of the internal transcribed spacer region of the rDNA gene confirmed the identification of the isolate as Exophiala attenuata. Reported here is the first confirmed case of feline phaeohyphomycosis caused by E. attenuata in North America. Similar to historical cases of feline phaeohyphomycosis caused by Exophiala spp., there was no history or postmortem evidence to suggest the patient was in an immunocompromised state (e.g., suffering from FeLV or FIV). Although aggressive surgical excision of local lesions is recommended prior to drug treatment when dealing with subcutaneous phaeohyphomycosis, surgery followed by itraconazole treatment did not resolve the E. attenuata infection in this cat.
5,079
Expression of a functional mouse-human chimeric anti-CD19 antibody in the milk of transgenic mice
Human B cell lymphomas are suitable targets for immunotherapy. Clinical trials with mouse-human chimeric B cell-specific monoclonal antibodies (mAbs) have already shown promising results. However, limitations for their use in clinical trials can be the lack of sufficient amounts and high production costs. Expression of mAbs in the mammary gland of transgenic animals provides an economically advantageous possibility for production of sufficient quantities of a promising antibody for clinical trials and beyond. In this paper, we show the feasibility of this approach, by generating transgenic mice expressing mouse-human chimeric anti-CD19 mAbs in their milk. Mouse anti-CD19 variable (V) region genes were combined with human IgG1 heavy (H) and kappa light (L) chain constant (C) region genes and fused to the bovine β-lactoglobulin (BLG) promoter in two separate expression cassettes. Co-injection resulted in five transgenic lines. In one of these lines completely assembled chimeric mAbs were secreted into the milk, at an approximate level of 0.5mg/ml. These mAbs were able to bind specifically to the CD19 surface antigen on human B cells.
5,080
Application of the polymerase chain reaction (PCR) in veterinary diagnostic virology
The polymerase chain reaction has become an important diagnostic tool for the veterinary virologist. Conventional methods for detecting viral diseases can be laborious or ineffective. In many cases PCR can provide a rapid and accurate test. In this article we explain the basic principles of PCR and supply a reference list of its uses in diagnostic veterinary virology.
5,081
Risk analysis for plant-made vaccines
The production of vaccines in transgenic plants was first proposed in 1990 however no product has yet reached commercialization. There are several risks during the production and delivery stages of this technology, with potential impact on the environment and on human health. Risks to the environment include gene transfer and exposure to antigens or selectable marker proteins. Risks to human health include oral tolerance, allergenicity, inconsistent dosage, worker exposure and unintended exposure to antigens or selectable marker proteins in the food chain. These risks are controllable through appropriate regulatory measures at all stages of production and distribution of a potential plant-made vaccine. Successful use of this technology is highly dependant on stewardship and active risk management by the developers of this technology, and through quality standards for production, which will be set by regulatory agencies. Regulatory agencies can also negatively affect the future viability of this technology by requiring that all risks must be controlled, or by applying conventional regulations which are overly cumbersome for a plant production and oral delivery system. The value of new or replacement vaccines produced in plant cells and delivered orally must be considered alongside the probability and severity of potential risks in their production and use, and the cost of not deploying this technology – the risk of continuing with the status quo alternative.
5,082
Avian influenza
The current epidemic of H5N1 highly pathogenic avian Influenza in Southeast Asia raises serious concerns that genetic reassortment will result in the next Influenza pandemic. There have been 164 confirmed cases of human infection with avian Influenza since 1996. In 2004 alone, there were 45 cases of human H5N1 in Vietnam and Thailand, with a mortality rate over 70%. In addition to the potential public health hazard, the current zoonotic epidemic has caused severe economic losses. Efforts must be concentrated on early detection of bird outbreaks with aggressive culling, quarantines, and disinfection. To prepare for and prevent increased human cases, it is essential to improve detection methods and stockpile effective antivirals. Novel therapeutic modalities, including short, interfering RNAs and new vaccine strategies that use plasmid-based genetic systems offer promise, should a pandemic occur.
5,083
“With Human Health It’s a Global Thing”: Canadian Perspectives on Ethics in the Global Governance of an Influenza Pandemic
We live in an era where our health is linked to that of others across the globe, and nothing brings this home better than the specter of a pandemic. This paper explores the findings of town hall meetings associated with the Canadian Program of Research on Ethics in a Pandemic (CanPREP), in which focus groups met to discuss issues related to the global governance of an influenza pandemic. Two competing discourses were found to be at work: the first was based upon an economic rationality and the second upon a humanitarian rationality. The implications for public support and the long-term sustainability of new global norms, networks, and regulations in global public health are discussed.
5,084
Evaluation of a Commercially Available Human Serum Amyloid A (SAA) Turbidimetric Immunoassay for Determination of Feline SAA Concentration
Serum amyloid A (SAA) is an acute-phase protein in cats likely to be useful for diagnosing and monitoring inflammatory diseases, especially if rapid, reliable and automated assays can be made available. A commercially available automated human SAA turbidimetric immunoassay (SAA-TIA) was evaluated for determination of SAA in cats. Intra-assay and inter-assay imprecisions were in the ranges 2.1–9.9% and 7.0–12.5%, respectively, and without significant inaccuracy. Eighty-eight cats were divided into groups according to (A) the presence or absence of an acute-phase response (APR) (n = 23 and 65, respectively) and (B) clinical diagnosis (clinically healthy cats, cats diagnosed with inflammatory/infectious diseases, endocrine/metabolic diseases, neoplastic diseases, and miscellaneous disorders (n=43, 13, 8, 4 and 20, respectively)). The observed SAA concentrations were, as expected, different for (A) cats with and without an APR and (B) cats with inflammatory/infectious diseases compared to other diagnostic groups, except neoplastic diseases. In conclusion, the SAA concentration in cats could be measured reliably using the commercially available TIA designed for measuring human SAA, which should facilitate implementation of the parameter for routine diagnostic purposes.
5,085
Sortilin as a Regulator of Lipoprotein Metabolism
Elevated low-density lipoprotein cholesterol (LDL-C) is associated with increased risk of atherosclerotic cardiovascular disease (ASCVD) and myocardial infarction (MI). Much of the insight into LDL metabolism has been gained through the study of Mendelian disorders of lipid metabolism. Genome-wide associations studies (GWAS) are now being used to identify novel genes and loci that contribute to variations in LDL-C levels, and they have identified the SORT1 gene as an important modulator of LDL-C levels and ASCVD risk. Mechanistic studies in mice and cell culture also suggest that the SORT1 gene is an important regulator of lipoprotein metabolism; however, these studies disagree on the directionality of the effect of Sort1 expression on plasma lipids and the mechanism for the lipid changes. Here we review the identification of the SORT1 locus as a modulator of LDL-C levels and ASCVD risk and the first mechanistic studies that explore the role of Sortilin in lipid metabolism.
5,086
Alterations in cell cycle dynamics in human endothelium cell culture infected with influenza virus
The cell cycle of endothelium EAhy 926 cell culture infected with influenza virus has been studied. Cytometric analysis of cell culture synchronized by contact inhibition revealed the elongation of the S phase of the cell cycle in EAhy 926 cells under the influence of influenza virus. This result was shown in an EAhy 926 culture infected with influenza virus and treated with nocodazole. Comparison of a lung carcinoma A549 cell line in which influenza virus causes G(0)/G(1) arrest and of an endothelial EAhy 926 cell line in which the same infection leads to S-phase elongation allows it to be suggested that different effects of influenza virus on cell cycle dynamics depend on the origin of infected cells.
5,087
Transcriptome profiling indicating canine parvovirus type 2a as a potential immune activator
Canine parvovirus type 2a (CPV-2a) is a variant of CPV-2, which is a highly contagious pathogen causing severe gastroenteritis and death in young dogs. However, how CPV-2 participates in cell regulation and immune response remains unknown. In this study, persistently infected MDCK cells were generated through culture passage of the CPV-2a-infected cells for ten generations. Our study showed that CPV-2a induces cell proliferation arrest and cell morphology alternation before the fourth generation, whereas, the cell morphology returns to normal after five times of passages. PCR detection of viral VP2 gene demonstrated that CPV-2a proliferate with cell passage. An immunofluorescence assay revealed that CPV-2a particles were mainly located in the cell nuclei of MDCK cell. Then transcriptome microarray revealed that gene expression pattern of MDCK with CPV-2a persistent infection is distinct compared with normal cells. Gene ontology annotation and Kyoto Encyclopedia of Genes and Genome pathway analysis demonstrated that CPV-2a infection induces a series of membrane-associated genes expression, including many MHC protein or MHC-related complexes. These genes are closely related to signaling pathways of virus–host interaction, including antigen processing and presentation pathway, intestinal immune network, graft-versus-host disease, and RIG-I-like helicases signaling pathway. In contrast, the suppressed genes mediated by CPV-2a showed low enrichment in any category, and were only involved in pathways linking to synthesis and metabolism of amino acids, which was confirmed by qPCR analysis. Our studies indicated that CPV-2a is a natural immune activator and has the capacity to activate host immune responses, which could be used for the development of antiviral strategy and biomaterial for medicine.
5,088
Interspecies transmission and host restriction of avian H5N1 influenza virus
Long-term endemicity of avian H5N1 influenza virus in poultry and continuous sporadic human infections in several countries has raised the concern of another potential pandemic influenza. Suspicion of the avian origin of the previous pandemics results in the close investigation of the mechanism of interspecies transmission. Entry and fusion is the first step for the H5N1 influenza virus to get into the host cells affecting the host ranges. Therefore receptor usage study has been a major focus for the last few years. We now know the difference of the sialic acid structures and distributions in different species, even in the different parts of the same host. Many host factors interacting with the influenza virus component proteins have been identified and their role in the host range expansion and interspecies transmission is under detailed scrutiny. Here we review current progress in the receptor usage and host factors.
5,089
On the Role of Asymptomatic Infection in Transmission Dynamics of Infectious Diseases
We propose a compartmental disease transmission model with an asymptomatic (or subclinical) infective class to study the role of asymptomatic infection in the transmission dynamics of infectious diseases with asymptomatic infectives, e.g., influenza. Analytical results are obtained using the respective ratios of susceptible, exposed (incubating), and asymptomatic classes to the clinical symptomatic infective class. Conditions are given for bistability of equilibria to occur, where trajectories with distinct initial values could result in either a major outbreak where the disease spreads to the whole population or a lesser outbreak where some members of the population remain uninfected. This dynamic behavior did not arise in a SARS model without asymptomatic infective class studied by Hsu and Hsieh (SIAM J. Appl. Math. 66(2), 627–647, 2006). Hence, this illustrates that depending on the initial states, control of a disease outbreak with asymptomatic infections may involve more than simply reducing the reproduction number. Moreover, the presence of asymptomatic infections could result in either a positive or negative impact on the outbreak, depending on different sets of conditions on the parameters, as illustrated with numerical simulations. Biological interpretations of the analytical and numerical results are also given.
5,090
Sequence Analysis of the S3 Gene from a Turkey Reovirus
The deduced σ2 protein sequence from the S3 gene segment of a novel turkey reovirus, designated NC98, isolated from the bursa of birds exhibiting poult enteritis and mortality syndrome was determined. The isolate, serologically distinct from other avian reoviruses, was isolated in turkey embryo kidney cells and RNA was purified for cDNA synthesis. Oligonucleotide primers were designed based on conserved avian S3 nucleotide sequence data. The NC98 S3 open reading frame comprised 1101 base pairs and encoded 366 amino acids with a predicated molecular mass of 40.5 kDa. Although the S3 nucleotide sequence from several chicken isolates share at least 86% identity, they share only 64% with the NC98 turkey isolate. Interestingly, the S3 nucleotide sequence from a muscovy duck reovirus shares 55% identity with NC98 and 53% identity with chicken isolates. As observed in other avian reovirus σ2 protein sequences, a zinc-binding motif and double-stranded RNA binding domain were found within the predicted amino acid sequence of NC98. Phylogenetic analysis of the deduced σ2 sequence demonstrated that NC98 separated as a distinct virus relative to other avian strains. The results of this study indicate that NC98 is a novel turkey reovirus that shares limited genomic sequence identity to isolates of chicken and duck origin and should be considered a separate virus species within subgroup 2 of the Orthoreovirus genus.
5,091
Avian Influenza
The current epidemic of H5N1 highly pathogenic avian influenza in Southeast Asia raises serious concerns that genetic reassortment will result in the next influenza pandemic. There have been 164 confirmed cases of human infection with avian influenza since 1996. In 2004, there were 45 cases of human H5N1 in Vietnam and Thailand, with a mortality rate more than 70%. In addition to the potential public health hazard, the current zoonotic epidemic has caused severe economic losses. Efforts must be concentrated on early detection of bird outbreaks with aggressive culling, quarantining, and disinfection. To prepare for and prevent an increase in human cases, it is essential to improve detection methods and stockpile effective antivirals. Novel therapeutic modalities, including short-interfering RNAs and new vaccine strategies that use plasmid-based genetic systems, offer promise should a pandemic occur.
5,092
Prevalence of subclinical coccidiosis in river buffalo calves of southwest of Iran
Despite the importance of buffalo farming in Iran, little is known in this country about the abundance and distribution of Eimeria spp. in the animal species. The present study was designed to investigate the prevalence and species characterization of Eimeria oocysts in river buffalo calves of Khuzestan province, southwest of Iran. Of the total 108 fecal samples examined for Eimeria, 108 (100%) were found infected with 11 species of the parasite. Among the identified species of Eimeria, E. bovis was found to be the predominant etiological agent (76.85%), followed in order by E. canadensis (62.96%), E. zuernii (47.2%), E. ellipsoidalis (26.85%), E. subspherica (25.92%), E. brasiliensis (19.4%), E. auburnensis (18.51%), E. alabamensis (14.81%), E. pellita (11.1%), E. illinoisensis (5.5%) and E. bukidnonensis (2.7%). In most calves multiple infections with three species were present. While, 20.7% of calves showed heavy infection, 50.4 and 24.8% of calves showed weak and moderate infection, respectively. There was no significant difference in the OPG values between the calves of different localities. There was also no significant difference between the prevalence rate of infection in males and females. A total of 16.6% of all faecal samples were found to be diarrheic. A highly significant relationship could be identified between the occurrence of diarrhea and the level of E. bovis and E. zuernii oocysts excretion. Considering the pervasive occurrence and negative effects of the infection on the health condition and the growth performance of buffalo calves, infections should receive increased attention by both farmers and veterinarians.
5,093
ROS and diseases: role in metabolism and energy supply
Researches dedicated to reactive oxygen species (ROS) had been performed for decades, yet the outcomes remain controversial. With the relentless effort of studies, researchers have explored the role of ROS in biosystem and various diseases. ROS are beneficial for biosystem presenting as signalling molecules and enhancing immunologic defence. However, they also have harmful effects such as causing tissue and organ damages. The results are controversial in studies focusing on ROS and ROS-related diseases by regulating ROS with inhibitors or promotors. These competing results hindered the process for further investigation of the specific mechanisms lying behind. The opinions presented in this review interpret the researches of ROS from a different dimension that might explain the competing results of ROS introduced so far from a broader perspective. This review brings a different thinking to researchers, with the neglected features and potentials of ROS, to relate their works with ROS and to explore the mechanisms between their subject and ROS.
5,094
Viral component of the human genome
Relationships between viruses and their human host are traditionally described from the point of view taking into consideration hosts as victims of viral aggression, which results in infectious diseases. However, these relations are in fact two-sided and involve modifications of both the virus and host genomes. Mutations that accumulate in the populations of viruses and hosts may provide them advantages such as the ability to overcome defense barriers of host cells or to create more efficient barriers to deal with the attack of the viral agent. One of the most common ways of reinforcing anti-viral barriers is the horizontal transfer of viral genes into the host genome. Within the host genome, these genes may be modified and extensively expressed to compete with viral copies and inhibit the synthesis of their products or modulate their functions in other ways. This review summarizes the available data on the horizontal gene transfer between viral and human genomes and discusses related problems.
5,095
Remote sensing and geographic information systems in the spatial temporal dynamics modeling of infectious diseases
Similar to species immigration or exotic species invasion, infectious disease transmission is strengthened due to the globalization of human activities. Using schistosomiasis as an example, we propose a conceptual model simulating the spatio-temporal dynamics of infectious diseases. We base the model on the knowledge of the interrelationship among the source, media, and the hosts of the disease. With the endemics data of schistosomiasis in Xichang, China, we demonstrate that the conceptual model is feasible; we introduce how remote sensing and geographic information systems techniques can be used in support of spatio-temporal modeling; we compare the different effects caused to the entire population when selecting different groups of people for schistosomiasis control. Our work illustrates the importance of such a modeling tool in supporting spatial decisions. Our modeling method can be directly applied to such infectious diseases as the plague, lyme disease, and hemorrhagic fever with renal syndrome. The application of remote sensing and geographic information systems can shed light on the modeling of other infectious disease and invasive species studies.
5,096
A stochastic recovery model of influenza pandemic effects on interdependent workforce systems
Outbreaks of infectious diseases, such as pandemics, can result in adverse consequences and major economic losses across various economic sectors. Based on findings from the 2009 A H1N1 pandemic in the National Capital Region (NCR), this paper presents a recovery analysis for workforce disruptions using economic input–output modeling. The model formulation takes into consideration the dynamic interdependencies across sectors in an economic system in addition to the inherent characteristics of the economic sectors. From a macroeconomic perspective, the risk of the influenza disaster can be modeled using two risk metrics. First, there is the level of inoperability, which represents the percentage difference between the ideal production level and the degraded production level. Second, the economic loss metric represents the financial value associated with the reduced output. The contribution of this work revolves around the modeling of uncertainties triggered by new perturbations to interdependent economic sectors within an influenza pandemic timeline. We model the level of inoperability of economic sectors throughout their recovery horizon from the initial outbreak of the disaster using a dynamic model. Moreover, we use the level of inoperability values to quantify the cumulative economic losses incurred by the sectors within the recovery horizon. Finally, we revisit the 2009 NCR pandemic scenario to demonstrate the use of uncertainty analysis in modeling the inoperability and economic loss behaviors due to time-varying perturbations and their associated ripple effects to interdependent economic sectors.
5,097
Translation in plants-rules and exceptions
Translation processes in plants are very similar to those in other eukaryotic organisms and can in general be explained with the scanning model. Particularly among plant viruses, unconventional mRNAs are frequent, which use modulated translation processes for their expression: leaky scanning, translational stop codon readthrough or frameshifting, and transactivation by virus-encoded proteins are used to translate polycistronic mRNAs; leader and trailer sequences confer (cap-independent) efficient ribosome binding, usually in an end-dependent mechanism, but true internal ribosome entry may occur as well; in a ribosome shunt, sequences within an RNA can be bypassed by scanning ribosomes. Translation in plant cells is regulated under conditions of stress and during development, but the underlying molecular mechanisms have not yet been determined. Only a small number of plant mRNAs, whose structure suggests that they might require some unusual translation mechanisms, have been described.
5,098
Molecular Characterization of Three New Avian Infectious Bronchitis Virus (IBV) Strains Isolated in Quebec
Three unrecognized field isolates of Infectious Bronchitis Virus (IBV) were recovered from commercial broiler chickens vaccinated with live Mass viral strain (H120). These isolates were identified by immunofluorescence using monoclonal antibodies produced against reference serotypes: Mass, Conn, and Ark. RT-PCRs were performed on viral RNAs to amplify S1 gene using a specific set of primers S1OLIGO3′ and S1OLIGO5′. Restriction polymorphism (RFLP) of PCR products was determined by the use of HaeIII restriction enzyme. As expected, patterns of PCR products were different from common pattern of strains assigned to Mass serotype M41, Beaudette, H120, and Florida. Molecular analysis showed a nucleotide insertion in hypervariable region one (HVR-1) of S1 gene of only Quebec isolates (Qu16, Qu_mv and Q_37zm). However, New Brunswick IBV isolate (NB_cp) did not display these insertions. Major amino acid changes involved insertion of two stretches (aa(118–119): Arg–Ser and aa(141–145): Sys–Ser–Asn–Ala–Ser–Cys) located at N-terminal and C-terminal regions of HVR-2. It is speculated that cysteine residue located upstream and downstream of Cys–Ser–Asn–Ala–Ser–Cys segment might be involved in the formation of loop structure and disulfide bond that could trigger important epitope changes. Insertion of new NXT and NXS (X≠P) glycosylation motifs scattered along S1 region and insertion of cysteine residues in HVR are contributing to the antigenic shifting of Quebec isolates. Fragment insertions were thought to be induced by inter-serotype recombination between vaccine strain (H120) that belongs to Mass serotype and another strain belonging to Ark serotype. Phylogenetic tree based on amino acid sequences showed that Quebec isolates formed a new phylogenetic cluster.
5,099
A two-step high-risk immunization based on high-risk immunization
In this paper, the two-step high-risk immunization was investigated based on high-risk immunization for the SIRS model in small-world networks and scale-free networks. First, the effects of various immunization schemes are studied and compared. When the number of immune is same, the research result shows that the immune effect of the two-step high-risk immunization strategy is not the best nor the worst. However, the practicability is better compare with others. Furthermore, by changing the proportional of immunization the optimal immune effect can be achieved in the two-step high-risk immunization. Computation results verify that the two-step high-risk immunization is effective, and it is economic and feasible in practice.