A novel conditioning-free hematopoietic stem cell transplantation model in zebrafish.
Transplantation is the most common assay for measuring the in vivo functionality of hematopoietic stem cells (HSCs). Although various HSC transplantation strategies have been developed in zebrafish, they are underutilized because of challenges related to immune matching and preconditioning toxicity. To circumvent these limitations, we developed a simple and robust transplantation model using HSC-deficient hosts. Homozygous runx1W84X mutants are devoid of definitive hematopoietic cells, including HSCs and adaptive immune cells; thus, they require no preconditioning regimen for transplantation. Marrow cell transplantation into runx1-mutant zebrafish 2 days after fertilization significantly improved their survival to adulthood and resulted in robust, multilineage, long-lasting, serially repopulating engraftment. Furthermore, we demonstrated that engraftment into runx1 homozygous mutants was significantly higher than into runx1 heterozygotes, demonstrating that the improved transplantation success is attributable to the empty HSC niche in mutants and not just the embryonic environment. Competitive transplantation of marrow cells into runx1 mutants revealed a stem cell frequency similar to that of murine marrow cells, which demonstrates the utility of this model for quantifying HSC function. The streamlined approach and robustness of this assay will help broaden its feasibility for future high-throughput transplantation experiments in zebrafish and will enable further novel discoveries in the biology of HSCs.


Current perspectives and recommendations for the development of mass spectrometry methods for the determination of allergens in foods.
Allergen detection and quantification is an essential part of allergen management as practiced by food manufacturers. Recently, protein MS methods (in particular, multiple reaction monitoring experiments) have begun to be adopted by the allergen detection community to provide an alternative technique to ELISA and PCR methods. MS analysis of proteins in foods provides additional challenges to the analyst, both in terms of experimental design and methodology: (1) choice of analyte, including multiplexing to simultaneously detect several biologically relevant molecules able to trigger allergic reactions; (2) choice of processing stable peptide markers for different target analytes that should be placed in publicly available databases; (3) markers allowing quantification (e.g., through standard addition or isotopically labeled peptide standards); (4) optimization of protease digestion protocols to ensure reproducible and robust method development; and (5) effective validation of methods and harmonization of results through the use of naturally incurred reference materials spanning several types of food matrix.


The Relationship between Electrical Stapedius Reflex Thresholds and Behaviorally Most Comfortable Levels in Experienced Cochlear Implant Users.
Programming the cochlear implant's speech processor with subjective methods in young, uncooperative children is difficult. Since young children cannot provide adequate feedback to the clinician, objective methods which do not require patient's response were often used. Electrical Stapedius Reflex Test is one of the most common procedures used. The goal of this study was to investigate the relationship between electricalstapedius reflex thresholds and behaviorally most comfortable levels in experienced cochlear implant users. The patients implanted with two brands of cochlear implants were compared in terms of electrical stapedius reflex thresholds versus most comfortable levels. Speech tests results were also compared between the two groups. 46 cochlear implanted patients who had at least 1 year of cochlear implant experience were included in the study. 28 patients were implanted with Nucleus, 18 patients with Med-El devices. Moderate correlations were obtained between Electrical Stapedius Reflex (ESR) thresholds and C levels in Nucleus users; higher correlations were obtained for Med-El patients. ESR thresholds were present at higher levels than MCL/C levels in both Nucleus and Med-El users. No significant difference was obtained between the two groups in terms of speech tests. ESR test can be very informative for programming young and uncooperative patients.


BDNF-dependent plasticity induced by peripheral inflammation in the primary sensory and the cingulate cortex triggers cold allodynia and reveals a major role for endogenous BDNF as a tuner of the affective aspect of pain.
Painful experiences are multilayered, composed of sensory, affective, cognitive and behavioral facets. Whereas it is well accepted that the development of chronic pain is due to maladaptive neuronal changes, the underlying molecular mechanisms, their relationship to the different pain modalities, and indeed the localization of these changes are still unknown. Brain-derived neurotrophic factor (BDNF) is an activity-dependent neuromodulator in the adult brain, which enhances neuronal excitability. In the spinal cord, BDNF underlies the development and maintenance of inflammatory and neuropathic pain. Here, we hypothesized that BDNF could be a trigger of some of these plastic changes. Our results demonstrate that BDNF is upregulated in the anterior cingulate cortex (ACC) and the primary sensory cortex (S1) in rats with inflammatory pain. Injections of recombinant BDNF (into the ACC) or a viral vector synthesizing BDNF (into the ACC or S1) triggered both neuronal hyperexcitability, as shown by elevated long-term potentiation, and sustained pain hypersensitivity. Finally, pharmacological blockade of BDNF-tropomyosin receptor kinase B (TrkB) signaling in the ACC, through local injection of cyclotraxin-B (a novel, highly potent, and selective TrkB antagonist) prevented neuronal hyperexcitability, the emergence of cold hypersensitivity, and passive avoidance behavior. These findings show that BDNF-dependent neuronal plasticity in the ACC, a structure known to be involved in the affective-emotional aspect of pain, is a key mechanism in the development and maintenance of the emotional aspect of chronic pain.


[Pathophysiologic mechanisms of early changes in renal hemodynamics in diabetes mellitus].
The early stages of diabetes mellitus are in some patients associated with renal haemodynamic changes resulting in increased glomerular filtration. This "diabetic hyperfiltration" is considered to be one of pathophysiological mechanisms and risk factors for the development of diabetic nephropathy. The aim of this paper is to review some contemporary views on pathophysiological mechanisms leading to this disorder with emphasis on the role impaired activity of humoral factors influencing renal haemodynamics. In addition to poor metabolic control due to insulinopenia there is a convincing experimental evidence suggesting the role of atrial natriuretic factor and endothelium-derived nitric oxide in mediating renal haemodynamic changes in diabetes. Enhanced renal activity of angiotensin I converting enzyme resulting in local overproduction of angiotensin II and accelerated degradation of kinins may be another factor contributing to the genesis of diabetic hyperfiltration. Hyperglycaemia induces changes in cellular signalling of these vasoactive systems. Furthermore, diabetes is a state of decreased capability of renal vascular bed to autoregulate blood flow likely due to altered activity of tubuloglomerular feedback and ion channels.


[Amphetamine--induced rage reaction in mice and its mechanism].
Rage reaction was induced in mice by ip amphetamine sulfate (APT) 15 mg/kg. Mice appeared hyperreactive after 6 min and then squeaked and fought each other. These manifestations were most distinct in 15-30 min and subsided after 40-70 min. At 20 degrees C and 25 degrees C, the occurrence of rage reaction was 85.0% and 90.0% respectively. The ED50 of APT for eliciting rage reaction was 11.8 +/- 2.1 mg/kg ip. No significant difference in the induction of rage reaction was observed between male and female mice but ambient temperature affected the occurrence of this reaction. Neuroleptic drugs (chlorpromazine, haloperidol, tardan and clozapine), anxiolytic drugs (diazepam and meprobamate) and reserpine suppressed the rage reaction induced by APT in mice. Phenobarbital and pentobarbital (at sedative doses), atropine, scopolamine, phentolamine and propranolol exerted no influence on APT--induced rage reaction. Amantadine, levodopa and apomorphine at lower doses potentiated the rage inducing effect of APT. Moreover, at higher doses amantadine or levodopa alone also evoked rage reaction similar to that induced by APT. Therefore, it may be deduced that the APT-induced rage reaction results from increased release of dopamine in limbic system and has nothing to do with the simultaneous epinephrine release. The available data indicate that the APT--induced rage reaction in mice deserves to be recommended as an animal model for screening potential neuroleptic drugs. The merits and shortcomings of this new model are discussed.


Crestal bone changes around titanium implants: a methodologic study comparing linear radiographic with histometric measurements.
Generally, endosseous implants can be placed according to a nonsubmerged or a submerged technique and in 1-piece or 2-piece configurations. Recently, it has been shown that peri-implant crestal bone reactions differ significantly radiographically as well as histometrically under such conditions and are dependent on a rough/smooth implant border in 1-piece implants and on the location of a microgap (interface) between the implant and the abutment/restoration in 2-piece configurations. The purpose of this study was to evaluate whether standardized radiography as a noninvasive clinical diagnostic method correlates with peri-implant crestal bone levels as determined by histometric analysis. Fifty-nine implants were placed in edentulous mandibular areas of 5 foxhounds in a side-by-side comparison in both submerged and nonsubmerged techniques. Three months after implant placement, abutment connection was performed in the submerged implant sites. At 6 months, all animals were sacrificed, and evaluations of the first bone-to-implant contact (fBIC), determined on standardized periapical radiographs, were compared to similar analyses made from nondecalcified histology. It was shown that both techniques provide the same information (Pearson correlation coefficient = 0.993; P < .001). The precision of the radiographs was within 0.1 mm of the histometry in 73.4% of the evaluations, while the level of agreement fell to between 0.1 and 0.2 mm in 15.9% of the cases. These data demonstrate in an experimental study that standardized periapical radiography can evaluate crestal bone levels around implants clinically accurately (within 0.2 mm) in a high percentage (89%) of cases. These findings are significant because crestal bone levels can be determined using a noninvasive technique, and block sectioning or sacrifice of the animal subject is not required. In addition, longitudinal evaluations can be made accurately such that bone changes over various time periods can be assessed. Such analyses may prove beneficial when trying to distinguish physiologic changes from pathologic changes or when trying to determine causes and effects of bone changes around dental implants.


Transcriptional responses of Arabidopsis thaliana plants to As (V) stress.
Arsenic is toxic to plants and a common environmental pollutant. There is a strong chemical similarity between arsenate [As (V)] and phosphate (Pi). Whole genome oligonucleotide microarrays were employed to investigate the transcriptional responses of Arabidopsis thaliana plants to As (V) stress. Antioxidant-related genes (i.e. coding for superoxide dismutases and peroxidases) play prominent roles in response to arsenate. The microarray experiment revealed induction of chloroplast Cu/Zn superoxide dismutase (SOD) (at2g28190), Cu/Zn SOD (at1g08830), as well as an SOD copper chaperone (at1g12520). On the other hand, Fe SODs were strongly repressed in response to As (V) stress. Non-parametric rank product statistics were used to detect differentially expressed genes. Arsenate stress resulted in the repression of numerous genes known to be induced by phosphate starvation. These observations were confirmed with qRT-PCR and SOD activity assays. Microarray data suggest that As (V) induces genes involved in response to oxidative stress and represses transcription of genes induced by phosphate starvation. This study implicates As (V) as a phosphate mimic in the cell by repressing genes normally induced when available phosphate is scarce. Most importantly, these data reveal that arsenate stress affects the expression of several genes with little or unknown biological functions, thereby providing new putative gene targets for future research.


Multimodal strategy for reduction of homologous transfusions in cranio-maxillofacial surgery.
The transfusion of homologous blood carries well-known risks that have prompted efforts to develop alternative techniques. Such measures are of particular interest to patients undergoing elective procedures. A total of 204 patients, out of 1470 patients who consecutively underwent major craniomaxillofacial procedures under general anesthesia over a two-year period, were enrolled in a prospective protocol to reduce homologous transfusion requirements when a blood loss in excess of 500 ml was anticipated. The data were compared with the results of a retrospective control group (n=2890) covering major procedures during the previous four years, when blood-saving measures were applied occasionally, but not based on a global strategy. Techniques for the reduction of homologous transfusions were acute normovolemic hemodilution, controlled moderate hypotension, cell saver and predeposit autologous blood. In addition, preoperative administration of human recombinant erythropoietin was introduced during the last year of the study. These techniques were applied individually or in combination, depending on contraindications specific for each technique, using invasive monitoring in order to maintain intraoperative hemodynamic stability. The goal of this study was to examine the extent to which homologous transfusions may be reduced with the systematic application of transfusion-sparing techniques. Of 204 patients qualifying for the transfusion-sparing protocol, 30 received homologous transfusions. In comparison to the control group, utilization of transfusion-sparing techniques had doubled. The overall reduction in the use of homologous transfusions was highly significant. When acute normovolemic hemodilution, controlled moderate hypotension and the cell saver were used in combination, a greater reduction in homologous transfusions was achieved than with the use of either a single modality or combination of any two. No transfusions were required in patients pretreated with erythropoietin.


Manipulating the Plasmodium genome.
Genome manipulation, the primary tool for assigning function to sequence, will be essential for understanding Plasmodium biology and malaria pathogenesis in molecular terms. The first success in transfecting Plasmodium was reported almost ten years ago. Gene-targeting studies have since flourished, as Plasmodium is haploid and integrates DNA only by homologous recombination. These studies have shed new light on the function of many proteins, including vaccine candidates and drug resistance factors. However, many essential proteins, including those involved in parasite invasion of erythrocytes, cannot be characterized in the absence of conditional mutagenesis. Proteins also cannot be identified on a functional basis as random DNA integration has not been achieved. We overview here the ways in which the Plasmodium genome can be manipulated. We also point to the tools that should be established if our goal is to address parasite infectivity in a systematic way and to conduct refined structure-function analysis of selected products.


Probing protein-tannin interactions by isothermal titration microcalorimetry.
Isothermal titration microcalorimetry (ITC) has been applied to investigate protein-tannin interactions. Two hydrolyzable tannins were studied, namely myrabolan and tara tannins, for their interaction with bovine serum albumin (BSA), a model globular protein, and gelatin, a model proline-rich random coil protein. Calorimetry data indicate that protein-tannin interaction mechanisms are dependent upon the nature of the protein involved. Tannins apparently interact nonspecifically with the globular BSA, leading to binding saturation at estimated tannin/BSA molar ratios of 48:1 for tara- and 178:1 for myrabolan tannins. Tannins bind to the random coil protein gelatin by a two-stage mechanism. The energetics of the first stage show evidence for cooperative binding of tannins to the protein, while the second stage indicates gradual saturation of binding sites as observed for interaction with BSA. The structure and flexibility of the tannins themselves alters the stoichiometry of the interaction, but does not appear to have any significant affect on the overall binding mechanism observed. This study demonstrates the potential of ITC for providing an insight into the nature of protein-tannin interactions.


What determines the size of occupational health services in UK universities?
There is wide, largely unexplained, variation in occupational health (OH) provision between UK employers. To explain the variation in OH provision across the UK university sector. Analyses of data from a survey of university OH services and from the Higher Education Statistics Agency. The outcome variable was clinical (doctor + nurse) staffing of the university's OH service. The explanatory variables examined were university size, income, research activity score and presence or absence of academic disciplines categorized by an expert panel as requiring a high level of OH provision. All 117 UK universities were included and 93 (79%) responded; with exclusions and incomplete data, between 80 and 89 were included in analyses. There was wide variation in clinical OH staffing (range 0-8.4 full-time equivalents). Number of university staff explained 34% of the variation in OH staffing. After adjusting for other factors, neither the research activity nor the presence of high-needs disciplines appeared to be factors currently used by employers to determine their investment in OH. Government or other guidelines for university employers should take organizational size into account. Employers may need guidance on how to provide OH services proportionate to specific occupational hazards or other OH needs.


A pilot cluster randomised trial of the medicines and alcohol consultation (MAC): an intervention to discuss alcohol use in community pharmacy medicine review services.
Alcohol interventions are important to the developing public health role of community pharmacies. The Medicines and Alcohol Consultation (MAC) is a new intervention, co-produced with community pharmacists (CPs) and patients, which involves a CP practice development programme designed to integrate discussion of alcohol within existing NHS medicine review services. We conducted a pilot trial of the MAC and its delivery to investigate all study procedures to inform progression to a definitive trial. This cluster pilot RCT was conducted in 10 community pharmacies in Yorkshire, UK, with a CP from each who regularly conducted Medicine Use Review (MUR) and New Medicine Service (NMS) consultations. Randomisation was conducted using a secure remote randomisation service. Intervention CPs (n = 5) were trained to deliver the MAC in MUR/NMS consultations. Control CPs (n = 5) provided these services as usual. Consecutive MUR/NMS patients were asked by CPs to participate, screened for eligibility (consumption of alcohol at least twice per week), and baseline data collected for those eligible. A two-month follow-up telephone interview was conducted. Blinding of CPs was not possible, but patients were blinded to the alcohol focus of the trial. Primary outcomes were total weekly UK units (8 g of ethanol per unit) of alcohol consumption in the week prior to follow-up, and confidence in medications management. Trial procedures were assessed by recruitment, attrition, and follow-up rates. 260 patients were approached by CPs to take part in the trial, 68% (n = 178) were assessed for eligibility and 30% (n = 54) of these patients were eligible. Almost all eligible patients (n = 51; 94%) consented to participate, of whom 92% (n = 47) were followed-up at 2 months; alcohol consumption was lower in the intervention arm and confidence in medication management reduced slightly for both groups. Exploration of recall issues at follow-up showed a high level of agreement between a two-item quantity/frequency measure and 7-day guided recall of alcohol consumption. The pilot trial demonstrates the feasibility of implementing the MAC in community pharmacy and trial recruitment and data collection procedures. However, decommissioning of MURs means that it is not possible to conduct a definitive trial of the intervention in this service. ISRCTN57447996.


Molecular alterations in signal pathways of melanoma and new personalized treatment strategies: Targeting of Notch.
Despite modern achievements in therapy of malignant melanomas new treatment strategies are welcomed in clinics for survival of patients. Now it is supposed that personalized molecular therapies for each patient are needed concerning a specificity of molecular alterations in patient's tumors. In human melanoma, Notch signaling interacts with other pathways, including MAPK, PI3K-AKT, NF-kB, and p53. This article discusses mutated genes and leading aberrant signal pathways in human melanoma which are of interest concerning to their perspective for personalized treatment strategies in melanoma. We speculate that E3 ubiquitin ligases MDM2 and MDM4 can be attractive therapeutic target for p53 and Notch signaling pathways in malignant melanoma by using small molecule inhibitors. It is possible that restoration of p53-MDM2-NUMB complexes in melanoma can restore wild type p53 function and positively modulate Notch pathway. In this review we summarize recent data about novel US Food and Drug Administration approved target drugs for metastatic melanoma treatment, and suppose model for treatment strategy by targeting Notch.


A disease-causing point mutation in human mitochondrial tRNAMet rsults in tRNA misfolding leading to defects in translational initiation and elongation.
The mitochondrial tRNA genes are hot spots for mutations that lead to human disease. A single point mutation (T4409C) in the gene for human mitochondrial tRNA(Met) (hmtRNA(Met)) has been found to cause mitochondrial myopathy. This mutation results in the replacement of U8 in hmtRNA(Met) with a C8. The hmtRNA(Met) serves both in translational initiation and elongation in human mitochondria making this tRNA of particular interest in mitochondrial protein synthesis. Here we show that the single 8U-->C mutation leads to a failure of the tRNA to respond conformationally to Mg(2+). This mutation results in a drastic disruption of the structure of the hmtRNA(Met), which significantly reduces its aminoacylation. The small fraction of hmtRNA(Met) that can be aminoacylated is not formylated by the mitochondrial Met-tRNA transformylase preventing its function in initiation, and it is unable to form a stable ternary complex with elongation factor EF-Tu preventing any participation in chain elongation. We have used structural probing and molecular reconstitution experiments to examine the structures formed by the normal and mutated tRNAs. In the presence of Mg(2+), the normal tRNA displays the structural features expected of a tRNA. However, even in the presence of Mg(2+), the mutated tRNA does not form the cloverleaf structure typical of tRNAs. Thus, we believe that this mutation has disrupted a critical Mg(2+)-binding site on the tRNA required for formation of the biologically active structure. This work establishes a foundation for understanding the physiological consequences of the numerous mitochondrial tRNA mutations that result in disease in humans.


Polarization-interleaved WDM signals in a fiber optical parametric amplifier with orthogonal pumps.
We have demonstrated a polarization-interleaved wavelength-division multiplexed system with a two-orthogonal-pump optical parametric amplifier. The sensitivity has been improved by about 2dB compared to its counterpart with all channels co-polarized, with the same signal gain, which itself dramatically improved over the conventional two-parallel-pump OPA.


Serotonin affects association of aversive outcomes to past actions.
Impairment in the serotonergic system has been linked to action choices that are less advantageous in a long run. Such impulsive choices can be caused by a deficit in linking a given reward or punishment with past actions. Here, we tested the effect of manipulation of the serotonergic system by tryptophan depletion and loading on learning the association of current rewards and punishments with past actions. We observed slower associative learning when actions were followed by a delayed punishment in the low serotonergic condition. Furthermore, a model-based analysis revealed a positive correlation between the length of the memory trace for aversive choices and subjects' blood tryptophan concentration. Our results suggest that the serotonergic system regulates the time scale of retrospective association of punishments to past actions.


Experience with a yes-no single-interval maximum-likelihood procedure.
The report in 1993 by Green [J. Acoust. Soc. Am. 93, 2096-2105 (1993)] describing the application of a new psychophysical method requiring few trials and little time to measure auditory thresholds has generated considerable interest among experimentalists. The procedure uses a single-interval stimulus presentation, requests a yes-no decision by subjects, and implements a maximum-likelihood calculation to determine the next trial stimulus level within an adaptive track, as well as the final threshold estimate. Data are presented here describing separate experiences with this procedure in two laboratories in both detection and discrimination tasks. Issues addressed include comparisons with more traditional psychophysical methods, variability in threshold estimates, experimental time required, and possible minor modifications to improve the basic procedure. Results using this procedure are comparable in terms of variability of estimates to those emerging from more lengthy procedures. However, because it may be difficult for some listeners to maintain a consistent criterion and because attentional lapses may be costly, experimenters must be willing to monitor performance closely and repeat some tracks in cases where excessively high variability is noted. Further, this procedure may not be suitable for tasks for which the form of the psychometric function is not well-established. Modifications allowing a variable slope parameter in the maximum-likelihood evaluations of psychometric functions may be of benefit.


Use of a continuous-flow device in patients awaiting heart transplantation.
The use of left ventricular assist devices is an accepted therapy for patients with refractory heart failure, but current pulsatile volume-displacement devices have limitations (including large pump size and limited long-term mechanical durability) that have reduced widespread adoption of this technology. Continuous-flow pumps are newer types of left ventricular assist devices developed to overcome some of these limitations. In a prospective, multicenter study without a concurrent control group, 133 patients with end-stage heart failure who were on a waiting list for heart transplantation underwent implantation of a continuous-flow pump. The principal outcomes were the proportions of patients who, at 180 days, had undergone transplantation, had cardiac recovery, or had ongoing mechanical support while remaining eligible for transplantation. We also assessed functional status and quality of life. The principal outcomes occurred in 100 patients (75%). The median duration of support was 126 days (range, 1 to 600). The survival rate during support was 75% at 6 months and 68% at 12 months. At 3 months, therapy was associated with significant improvement in functional status (according to the New York Heart Association class and results of a 6-minute walk test) and in quality of life (according to the Minnesota Living with Heart Failure and Kansas City Cardiomyopathy questionnaires). Major adverse events included postoperative bleeding, stroke, right heart failure, and percutaneous lead infection. Pump thrombosis occurred in two patients. A continuous-flow left ventricular assist device can provide effective hemodynamic support for a period of at least 6 months in patients awaiting heart transplantation, with improved functional status and quality of life. (ClinicalTrials.gov number, NCT00121472 [ClinicalTrials.gov].).


Betrayal trauma among homeless adults: associations with revictimization, psychological well-being, and health.
Betrayal trauma theory postulates that traumas perpetrated by a caregiver or close other are more detrimental to mental health functioning than are traumatic experiences in which the victim is not affiliated closely with the perpetrator. This study is the first to examine the concept of betrayal among a sample of individuals with a history of homelessness. A total of 95 homeless or formerly homeless adults completed the Brief Betrayal Trauma Survey, the Posttraumatic Stress Disorder Checklist-Civilian Version, the Center for Epidemiologic Studies Depression Scale the Perceived Stress Scale, and a demographics questionnaire assessing participants' histories of homelessness, health, and relationships with their families. Regression analyses were conducted to explore the associations between high betrayal (HB) and low betrayal (LB) trauma exposure, relationship with family, and physical and mental health symptoms. Exposure to HB traumas in childhood and poor family relationships predicted earlier age at first episode of homelessness, and participants who had been exposed to a greater number of traumas during childhood were more likely to be revictimized during adulthood. Trauma exposure as an adult and earlier age of first homeless episode predicted symptoms of posttraumatic stress disorder, while trauma exposure alone predicted symptoms of depression and perceived stress. Number of medical diagnoses was associated with trauma exposure and becoming homeless at an older age. These findings emphasize that even among the most marginalized and multiply victimized individuals in our society, traumas that are characterized by a higher degree of betrayal are associated with more adverse outcomes.


Formation of hollow silica nanospheres by reverse microemulsion.
Uniform hollow silica nanospheres (HSNs) synthesized with reverse microemulsion have great application potential as nanoreactors because enzymes or nanocatalysts can be easily encapsulated de novo in synthesis. Water-in-oil (w/o) reverse microemulsions comprising the polymeric surfactant polyoxyethylene (5) isooctylphenyl ether (Igepal CA-520), ammonia and water in a continuous oil phase (alkanes) coalesce into size-tunable silica nanoparticles via diffusion aggregation after the introduction of silica precursors. Here, we elucidate in detail the growth mechanism for silica nanoparticles via nucleation of ammonium-catalyzed silica oligomers from tetraethylorthosilicate (TEOS) and nanoporous aminopropyltrimethoxy silane (APTS) in the reverse microemulsion system. The formation pathway was studied in situ with small-angle X-ray scattering (SAXS). We find a four-stage process showing a sigmoidal growth behavior in time with a crossover from the induction period, early nucleation stage, coalescence growth and a final slowing down of growth. Various characterizations (TEM, N2 isotherm, dynamic light scattering, zeta potential, NMR, elemental analysis) reveal the diameters, scattering length density (SLD), mesoporosity, surface potentials and chemical compositions of the HSNs. Oil phases of alkanes with different alkyl chains are systematically employed to tune the sizes of HSNs by varying oil molar volumes, co-solvent amounts or surfactant mixture ratios. Silica condensation is incomplete in the core region, with the silica source of TEOS and APTS leading to the hollow silica nanosphere after etching with warm water.


Outcomes in adolescents and young adults with Hodgkin lymphoma treated on US cooperative group protocols: An adult intergroup (E2496) and Children's Oncology Group (COG AHOD0031) comparative analysis.
There is no clear consensus between pediatric and adult providers about the treatment of adolescents and young adults (AYAs) with Hodgkin lymphoma (HL). Failure-free survival (FFS) and overall survival (OS) were compared between 114 patients ages 17 to 21 years with HL who were treated on the Eastern Cooperative Oncology Group-American College of Radiology Imaging Network Intergroup adult E2496 study and 391 similarly patients ages 17 to 21 years with HL who were treated on the pediatric Children's Oncology Group (COG) AHOD0031 study. Comparing AYAs from the COG and E2496 studies, there were no significant differences in extralymphatic disease, anemia, or hypoalbuminemia. More AYAs in the E2496 trial had stage III and IV disease (63% vs 29%; P < .001) and B symptoms (63% vs 27%; P < .001), and fewer had bulk disease (33% vs 77%; P < .001). More AYAs on the COG trial received radiotherapy (76% vs 66%; P = .03), although in smaller doses. E2496 AYA The 5-year FFS and OS rates were 68% and 89%, respectively in the E2496 AYAs and 81% and 97%, respectively, in the COG AYAs, indicating a statistically superior compared in the COG AYAs (P = .001). In stratified multivariable analyses, E2496 AYAs had worse FFS than COG AYAs in all strata except patients who had stage I and II HL without anemia. Propensity score analysis (based on stage, anemia, and bulk disease) confirmed inferior FFS for E2496 AYAs compared with COG AYAs (P = .004). On the E2496 study, FFS was significantly divergent across age groups (P = .005), with inferior outcomes for those ages 17 to 21 years versus 22-44 years. There was no difference across age on the COG study. Younger AYA patients with HL appear to have better outcomes when treated on a pediatric trial than patients of similar age on an adult trial. Prospective studies examining these differences are warranted. Cancer 2018;124:136-44. © 2017 American Cancer Society.


Visualizing Central Line -Associated Blood Stream Infection (CLABSI) Outcome Data for Decision Making by Health Care Consumers and Practitioners-An Evaluation Study.
The purpose of this study was to evaluate information visualization of publicly-reported central line-associated blood stream infection (CLABSI) outcome data for decision making by diverse target audiences - health care consumers and practitioners. We describe the challenges in publicly reporting of healthcare-associated infections (HAIs) data and the interpretation of an evaluation metric. Several options for visualization of CLABSI data were designed and evaluated employing exploratory working group, two confirmatory focus groups' observations, and experts' committee validation of the final designs. Survey-data collection and evaluation criteria results, collected from the two focus groups, are presented and are used to develop the final recommendations for how to visualize publicly-reported CLABSI data from Maryland acute care hospitals. Both health care consumer and practitioner's perspectives are highlighted and categorized based on the visualizations' dimensions framework. Finally, a recommended format for visualizing CLABSI outcome data based on the evaluation study is summarized.


Particulate-phase mercury emissions from biomass burning and impact on resulting deposition: a modelling assessment.
Mercury (Hg) emissions from biomass burning (BB) are an important source of atmospheric Hg and a major factor driving the interannual variation of Hg concentrations in the troposphere. The greatest fraction of Hg from BB is released in the form of elemental Hg(Hg(g)0) . However, little is known about the fraction of Hg bound to particulate matter (HgP) released from BB, and the factors controlling this fraction are also uncertain. In light of the aims of the Minamata Convention to reduce intentional Hg use and emissions from anthropogenic activities, the relative importance of Hg emissions from BB will have an increasing impact on Hg deposition fluxes. Hg speciation is one of the most important factors determining the redistribution of Hg in the atmosphere and the geographical distribution of Hg deposition. Using the latest version of the Global Fire Emissions Database (GFEDv4.1s) and the global Hg chemistry transport model, ECHMERIT, the impact of Hg speciation in BB emissions, and the factors which influence speciation, on Hg deposition have been investigated for the year 2013. The role of other uncertainties related to physical and chemical atmospheric processes involving Hg and the influence of model parametrisations were also investigated, since their interactions with Hg speciation are complex. The comparison with atmospheric HgP concentrations observed at two remote sites, Amsterdam Island (AMD) and Manaus (MAN), in the Amazon showed a significant improvement when considering a fraction of HgP from BB. The set of sensitivity runs also showed how the quantity and geographical distribution of HgP emitted from BB has a limited impact on a global scale, although the inclusion of increasing fractions HgP does limit Hg(g)0 availability to the global atmospheric pool. This reduces the fraction of Hg from BB which deposits to the world's oceans from 71 to 62 %. The impact locally is, however, significant on northern boreal and tropical forests, where fires are frequent, uncontrolled and lead to notable Hg inputs to local ecosystems. In the light of ongoing climatic changes this effect could be potentially be exacerbated in the future.


The physiological and ventilatory responses to repeated 60 s sprints following sodium citrate ingestion.
This study examined the influence of sodium citrate on changes in selected blood, ventilatory and performance variables in response to intermittent sprint exercise. Eight moderately active male students completed three tests over a 6 day experimental period. The first test involved incremental exercise to determine VO2 max, while the second and third tests were identical in nature and involved five 60 s sprints cycling against 0.075 kg kg-1 body mass (BM); each of the five sprints was separated by 5 min passive seated recovery. Three days separated the VO2 max test and first interval test, while a further 3 days elapsed between the first and second interval tests. Ninety minutes prior to each interval test, the subjects consumed either a solution of sodium citrate (0.5 g kg-1 BM) or a placebo solution (1 g of calcium carbonate and 4 mg of sodium chloride). These were randomly administered in a double-blind crossover procedure so that every subject consumed each solution prior to the interval test over the 6 day period. Measures of work, VE, VO2, VCO2, post-exercise plasma lactate, and changes in both venous blood pH and venous blood bicarbonate (HCO3-) were measured during each interval test. Although analysis of variance failed to identify differences in performance between the two solutions, both exercise VCO2 and changes in venous blood HCO3- were higher in the citrate condition (P < 0.05). In addition, both peak post-exercise plasma lactate concentrations and post-exercise venous blood pH were significantly higher following citrate ingestion. Although these data are consistent with greater clearance of lactate and H+ from the active muscle cells following citrate ingestion, performance between the two trials was the same.(ABSTRACT TRUNCATED AT 250 WORDS)


A novel flow-system to establish experimental biofilms for modelling chronic wound infection and testing the efficacy of wound dressings.
Several models exist for the study of chronic wound infection, but few combine all of the necessary elements to allow high throughput, reproducible biofilm culture with the possibility of applying topical antimicrobial treatments. Furthermore, few take into account the appropriate means of providing nutrients combined with biofilm growth at the air-liquid interface. In this manuscript, a new biofilm flow device for study of wound biofilms is reported. The device is 3D printed, straightforward to operate, and can be used to investigate single and mixed species biofilms, as well as the efficacy of antimicrobial dressings. Single species biofilms of Staphylococcus aureus or Pseudomonas aeruginosa were reproducibly cultured over 72 h giving consistent log counts of 8-10 colony forming units (CFU). There was a 3-4 log reduction in recoverable bacteria when antimicrobial dressings were applied to biofilms cultured for 48 h, and left in situ for a further 24 h. Two-species biofilms of S. aureus and P. aeruginosa inoculated at a 1:1 ratio, were also reproducibly cultured at both 20 °C and 37 °C; of particular note was a definitive Gram-negative shift within the population that occurred only at 37 °C.


Impaired cued and contextual memory in NPAS2-deficient mice.
Neuronal PAS domain protein 2 (NPAS2) is a basic helix-loop-helix (bHLH) PAS domain transcription factor expressed in multiple regions of the vertebrate brain. Targeted insertion of a beta-galactosidase reporter gene (lacZ) resulted in the production of an NPAS2-lacZ fusion protein and an altered form of NPAS2 lacking the bHLH domain. The neuroanatomical expression pattern of NPAS2-lacZ was temporally and spatially coincident with formation of the mature frontal association/limbic forebrain pathway. NPAS2-deficient mice were subjected to a series of behavioral tests and were found to exhibit deficits in the long-term memory arm of the cued and contextual fear task. Thus, NPAS2 may serve a dedicated regulatory role in the acquisition of specific types of memory.


Ketoconazole therapy: an efficacious alternative to achieve eucortisolism in patients with Cushing's syndrome.
Cushing's syndrome (CS) is a serious condition requiring drug management in diverse clinical settings. Fifty four patients (44 females, 10 males) with CS, aged 14-63, received ketoconazole (KTZ) prior to surgery (n= 27), as complementary therapy after surgery and/or radiotherapy (n= 16), or as primary treatment (n= 11). It was given at a 600 (500 - 600) mg/day (median - Cl195) maintenance dose for periods ranging from 15 days to 13 years. Clinical signs, hepatic enzymes and urinary free cortisol (UFC) were evaluated before and during KTZ treatment. UFC normalised or decreased to subnormal values in 85% of the patients, in 5 to 150 days after starting treatment; although failing to normalise, UFC decreased to 12-48% of pre-treatment values in the remaining patients. Clinical signs improved throughout. Side effects were adrenal insufficiency (18.5%), reversible hepatic toxicity (11%), allergic skin rash (5.5%) and gastric intolerance (3.7%); in 11% of patients, an "escape phenomenon" was observed. Twenty-four out of the total (44.4%) were treated for prolonged periods, from one up to 13 years. In conclusion, this study confirms that KTZ is an effective and generally well tolerated treatment for CS particularly: a) shortly before surgery, b) because of persistent hypercortisolism after surgery or awaiting the results of radiotherapy, c) as a reasonable option in patients with CS of unknown aetiology and, d) as long-term therapy in any case of unsolved hypercortisolism after failure of current treatments.


Effects of housing density and cage floor space on C57BL/6J mice.
The Guide for the Care and Use of Laboratory Animals (the Guide) is widely accepted as the housing standard by most Institutional Animal Care and Use Committees. The recommendations are based on best professional judgment rather than experimental data. Current efforts are directed toward replacing these guidelines with data-driven, species-appropriate standards. Our studies were undertaken to determine the optimum housing density for C57BL/6J mice, the most commonly used inbred mouse strain. Four-week-old mice were housed for 8 weeks at four densities (the recommended approximately 12 in2 [ca. 77.4 cm2]/mouse down to 5.6 in2 [ca. 36.1 cm2]/mouse) in three cage types with various amounts of floor space. Housing density did not affect a variety of physiologic parameters but did affect certain micro-environmental parameters, although these remained within accepted ranges. A second study was undertaken housing C57BL/6J mice with as little as 3.2 in2/mouse (ca. 20.6 cm2). The major effect was elevated ammonia concentrations that exceeded limits acceptable in the workplace at increased housing densities; however, the nasal passages and eyeballs of the mice remained microscopically normal. On the basis of these results, we conclude that C57BL/6J mice as large as 29 g may be housed with 5.6 in2 of floor space per mouse. This area is approximately half the floor space recommended in the Guide. The role of the Guide is to ensure that laboratory animals are well treated and housed in a species-appropriate manner. Our data suggest that current policies could be altered in order to provide the optimal habitation conditions matched to this species' social needs.


Ursolic Acid Protected Lung of Rats From Damage Induced by Cigarette Smoke Extract.
Background: We found previously that ursolic acid (UA) administration could alleviate cigarette smoke-induced emphysema in rats partly through the unfolded protein response (UPR) PERK-CHOP and Nrf2 pathways, thus alleviating endoplasmic reticulum stress (ERS)-associated oxidative stress and cell apoptosis. We hypothesized that other UPR pathways may play similar roles in cigarette smoke extract (CSE)-induced emphysema. So, we sought to investigate the dynamic changes and effects of UPR and the downstream apoptotic pathways. Further, we investigated whether UA could alleviate CSE-induced emphysema and airway remodelling in rats, whether and when it exerts its effects through UPR pathways as well as Smads pathways. Methods: One hundred eight Sprague Dawley (SD) rats were randomly divided into three groups: Sham group, CSE group, and UA group, and each group was further divided into three subgroups, administered CSE (vehicle) for 2, 3, or 4 weeks; each subgroup had 12 rats. We examined pathological changes, analyzed the three UPR signaling pathways and subsequent ERS, intrinsic and extrinsic apoptotic pathway indicators, as well as activation of Smad2,3 molecules in rat lungs. Results: Exposure to CSE for 3 or 4 weeks could apparently induce emphysema and airway remodeling in rats, including gross and microscopic changes, alteration of mean alveolar number (MAN), mean linear intercept (MLI), and mean airway thickness in lung tissue sections. UA intervention could significantly alleviate CSE-induced emphysema and airway remodeling in rats. UA exerted its effects through ameliorating apoptosis by down regulating UPR signalling pathways and subsequent apoptosis pathways, as well as, downregulating p-Smad2 and p-Smad3 molecules. Conclusions: UA attenuated CSE-induced emphysema and airway remodeling, exerting its effects partly through regulation of three UPR pathways, amelioration downstream apoptotic pathways, and alleviating activation of Smad2 and Smad3.


pGenN, a gene normalization tool for plant genes and proteins in scientific literature.
Automatically detecting gene/protein names in the literature and connecting them to databases records, also known as gene normalization, provides a means to structure the information buried in free-text literature. Gene normalization is critical for improving the coverage of annotation in the databases, and is an essential component of many text mining systems and database curation pipelines. In this manuscript, we describe a gene normalization system specifically tailored for plant species, called pGenN (pivot-based Gene Normalization). The system consists of three steps: dictionary-based gene mention detection, species assignment, and intra species normalization. We have developed new heuristics to improve each of these phases. We evaluated the performance of pGenN on an in-house expertly annotated corpus consisting of 104 plant relevant abstracts. Our system achieved an F-value of 88.9% (Precision 90.9% and Recall 87.2%) on this corpus, outperforming state-of-art systems presented in BioCreative III. We have processed over 440,000 plant-related Medline abstracts using pGenN. The gene normalization results are stored in a local database for direct query from the pGenN web interface (proteininformationresource.org/pgenn/). The annotated literature corpus is also publicly available through the PIR text mining portal (proteininformationresource.org/iprolink/).


Risk factors for recurrent primary sclerosing cholangitis after liver transplantation.
The association between primary sclerosing cholangitis (PSC) and inflammatory bowel disease (IBD) is well recognised. However, the relationship between IBD and recurrent PSC (rPSC) is less well understood. We assessed the prevalence of rPSC and analysed the factors associated with rPSC post-liver transplantation and its influence on graft and patient survival. This is a UK multicentre observational cohort study across six of the seven national liver transplant units. All patients undergoing a first liver transplant for PSC between January 1 1990 and December 31 2010 were included. Prospectively collected liver transplant data was obtained from NHSBT and colitis data was retrospectively collected from individual units. There were 679 (8.8%) first transplants for PSC. 347 patients (61.4%) had IBD, of which 306 (88.2%) had ulcerative colitis (UC). 81 (14.3%) patients developed rPSC and 37 (48.7%) of them developed graft failure from rPSC. Presence of UC post-liver transplant (HR=2.40, 95% CI 1.44-4.02) and younger age (HR=0.78, 95% CI 0.66-0.93) were the only factors significantly associated with rPSC. rPSC was associated with over a 4-fold increase in the risk of death (HR=4.71, 95% CI 3.39, 6.56) with 1, 5, and 10-year graft survival rates of 98%, 84%, and 56% respectively compared to 95%, 88%, and 72% in patients who did not develop rPSC. The presence of UC post-liver transplant is associated with a significantly increased risk of rPSC. Furthermore, the presence of rPSC increases the rate of graft failure and death, with higher re-transplantation rates.


Assessment of coronary artery remodelling by dual-source CT: a head-to-head comparison with intravascular ultrasound.
While it is widely assumed that coronary CT angiography permits detection and quantification of 'positive remodelling' of coronary atherosclerotic lesions, there is a paucity of data comparing CT with established reference methods. To assess the accuracy of dual-source CT for detecting positive versus absent or negative coronary artery remodelling of coronary atherosclerotic lesions as compared with intravascular ultrasound (IVUS). The datasets were evaluated of 38 patients referred for invasive coronary angiography and in whom an IVUS study of one coronary vessel was performed. Coronary CT angiography was performed within 24 h before invasive coronary angiography. Using dual-source CT (Siemens Healthcare, Forchheim, Germany), a contrast-enhanced volume dataset was acquired (120 kV, 400 mA/rot, collimation 2×64×0.6 mm, 60-80 ml contrast agent, intravenous). IVUS was performed using a 40 MHz IVUS catheter (Atlantis, Boston Scientific Corporation, Natick, Massachusetts, USA) and motorised pullback at 0.5 mm/s. 48 corresponding non-calcified and partially calcified plaques within the coronary artery system were identified in both CT and IVUS using bifurcation points as fiducial markers. In CT datasets, multiplanar reconstructions orthogonal to the centre line of the coronary artery were rendered and cross-sectional vessel area was measured at the site of maximal narrowing as well as at a reference segment proximal to the lesion for each of the 48 plaques. The remodelling index (RI) was calculated by dividing the vessel area at the site of maximal narrowing by the area of the reference segment. Corresponding vessel areas and RIs were also determined in IVUS. CT classified 41 plaques as positively remodelled (RI≥1.05) and seven as having either absent or negative remodelling (RI<1.05). In IVUS 29 plaques demonstrated positive remodelling, while 19 did not. Mean cross-sectional vessel areas measured by CT at the lesion and at the reference segment were 19±5 mm(2) and 17± 5 mm(2), respectively, versus 18±5 mm(2) and 17±5 mm(2) for IVUS (mean difference 1±2 mm(2) and -0.2±1 mm(2), p<0.0001 and 0.8, respectively). The mean RI in CT was significantly larger than in IVUS (1.2±0.2 vs 1.1±0.2, p<0.0001). Correlation between CT and IVUS was higher for vessel area measurements (r>0.9, p<0.0001) than for remodelling indices (r=0.7, p<0.0001) with Bland-Altman analysis showing a systematic overestimation of vessel areas and RI in CT. Interobserver agreement was moderate for CT and IVUS measurements. Receiver operating characteristic curve analysis showed that a RI of 1.1 in CT identified positively remodelled plaques in IVUS with a sensitivity of 83% and a specificity of 78% (area under the curve=0.8, 95% CI 0.7 to 1.0). Using the standard cut-off point of 1.05 to identify positively remodelled plaques in CT resulted in a sensitivity of 100%, and a specificity of 45%. Coronary CT angiography allows analysis of coronary artery remodelling. The degree of positive remodelling is typically overestimated by CT. A threshold of 1.1 for the RI may be optimal to classify plaques as 'positively remodelled' in coronary CT angiography.


Secretagogue response of goblet cells and columnar cells in human colonic crypts.
Crypts of Lieberkühn were isolated from human colon, and differential interference contrast microscopy distinguished goblet and columnar cells. Activation with carbachol (CCh, 100 microM) or histamine (10 microM) released contents from goblet granules. Stimulation with prostaglandin E(2) (PGE(2), 5 microM) or adenosine (10 microM) did not release goblet granules but caused the apical margin of columnar cells to recede. Goblet volume was lost during stimulation with CCh or histamine ( approximately 160 fl/cell), but not with PGE(2) or adenosine. Three-quarters of goblet cells were responsive to CCh but released only 30% of goblet volume. Half-time for goblet volume release was 3.7 min. PGE(2) stimulated a prolonged fluid secretion that attained a rate of approximately 350 pl/min. Columnar cells lost approximately 50% of apical volume during maximal PGE(2) stimulation, with a half-time of 3.3 min. In crypts from individuals with ulcerative colitis, goblet cells were hypersensitive to CCh for release of goblet volume. These results support separate regulation for mucus secretions from goblet cells and from columnar cells, with control mechanisms restricting total release of mucus stores.


Is There a Preinterventional Mechanical Ventilation Time Limit for Candidates of Adult Respiratory Extracorporeal Membrane Oxygenation.
Venovenous extracorporeal membrane oxygenation (VV-ECMO) is a useful life support in severe acute respiratory distress syndrome (ARDS). Although prolonged mechanical ventilation (MV) before institution of ECMO is known to be a poor prognostic factor for outcomes of VV-ECMO, a reasonable deadline for this period has not been defined yet. To discover the answer, we reviewed a 9 year institutional experience of adult respiratory ECMO in VV configuration and investigate the relationship between the MV time before ECMO and in-hospital mortality. This retrospective study included 129 adult patients receiving VV-ECMO for ARDS in a single institution from 2007 to 2016. Important demographic and clinical data before ECMO intervention were collected for analyses of in-hospital mortality. The MV time before ECMO independently predicted hospital death in adult respiratory ECMO here. While compared to the patients receiving MV for 7 days or less, the patients receiving MV for more than 7 days before ECMO showed a higher in-hospital mortality rate (77% vs. 38%, p < 0.001). They also experienced a more significant deterioration in respiratory function during MV before the institution of ECMO. Therefore, from the clinical observation, we thought that a 7 day period might be an acceptable limit on MV time before institution of VV-ECMO. Integrating other respiratory parameters into the current PaO2/FiO2 (PF) ratio-based inclusion criteria of adult respiratory ECMO might be helpful to reduce the risk of prolonged MV in selected patients.


Computational identification of surrogate genes for prostate cancer phases using machine learning and molecular network analysis.
Prostate cancer is one of the most common malignant diseases and is characterized by heterogeneity in the clinical course. To date, there are no efficient morphologic features or genomic biomarkers that can characterize the phenotypes of the cancer, especially with regard to metastasis--the most adverse outcome. Searching for effective surrogate genes out of large quantities of gene expression data is a key to cancer phenotyping and/or understanding molecular mechanisms underlying prostate cancer development. Using the maximum relevance minimum redundancy (mRMR) method on microarray data from normal tissues, primary tumors and metastatic tumors, we identifed four genes that can optimally classify samples of different prostate cancer phases. Moreover, we constructed a molecular interaction network with existing bioinformatic resources and co-identifed eight genes on the shortest-paths among the mRMR-identified genes, which are potential co-acting factors of prostate cancer. Functional analyses show that molecular functions involved in cell communication, hormone-receptor mediated signaling, and transcription regulation play important roles in the development of prostate cancer. We conclude that the surrogate genes we have selected compose an effective classifier of prostate cancer phases, which corresponds to a minimum characterization of cancer phenotypes on the molecular level. Along with their molecular interaction partners, it is fairly to assume that these genes may have important roles in prostate cancer development; particularly, the un-reported genes may bring new insights for the understanding of the molecular mechanisms. Thus our results may serve as a candidate gene set for further functional studies.


Effects of robotic knee exoskeleton on human energy expenditure.
A number of studies discuss the design and control of various exoskeleton mechanisms, yet relatively few address the effect on the energy expenditure of the user. In this paper, we discuss the effect of a performance augmenting exoskeleton on the metabolic cost of an able-bodied user/pilot during periodic squatting. We investigated whether an exoskeleton device will significantly reduce the metabolic cost and what is the influence of the chosen device control strategy. By measuring oxygen consumption, minute ventilation, heart rate, blood oxygenation, and muscle EMG during 5-min squatting series, at one squat every 2 s, we show the effects of using a prototype robotic knee exoskeleton under three different noninvasive control approaches: gravity compensation approach, position-based approach, and a novel oscillator-based approach. The latter proposes a novel control that ensures synchronization of the device and the user. Statistically significant decrease in physiological responses can be observed when using the robotic knee exoskeleton under gravity compensation and oscillator-based control. On the other hand, the effects of position-based control were not significant in all parameters although all approaches significantly reduced the energy expenditure during squatting.


One hundred years of helicene chemistry. Part 2: stereoselective syntheses and chiral separations of carbohelicenes.
Carbohelicenes generally incorporate a helical, distorted, conjugated, polyaromatic system with ortho-fused benzenoid rings, which is a fundamental molecular characteristic of this class of compounds. They have been described as "molecules in distress" due to their distortion. The generation of a chiral helicity in helicenes was observed because of a severe intramolecular steric strain. Helicity is a molecular necessity in the higher series of carbohelicenes, when at some point, a helical pitch occurs when a second coil is formed. The most interesting properties resulting from such molecular distortion are the very high chiroptical and circular dichroism values. For instance, the resolution of some helicene racemates by "hand picking" of a few homochiral single enantiomeric crystals allowed for a measurement of their optical rotation. Due to that intrinsic chirality spanned over a large polyaromatic template, preliminary results clearly established the efficiency of carbohelicenes to induce asymmetry and chirality in organic synthesis and in supramolecular chemistry. Additionally, they have some potential uses in several fields: materials science, nanoscience, chemical biology and supramolecular chemistry. It has encouraged many attempts to develop new asymmetric syntheses of carbohelicenes, as well as some chiral separations of enantiomers and diastereoisomers. This review is thus dedicated to carbohelicene chirality. It gathered a substantial collection of data, and a comprehensive review on the preparations of enantioenriched helicenes, either from an asymmetric synthesis or from a chiral separation. Utilizations of non-racemic helicenes and their applications will be treated in the following review (Part 3), and will not be the subject of this manuscript.


Screening for tuberculosis infection among newly arrived asylum seekers: comparison of QuantiFERONTB Gold with tuberculin skin test.
QuantiFERONTB Gold (QFT) is a promising blood test for tuberculosis infection but with few data so far from immigrant screening. The aim of this study was to compare results of QFT and tuberculin skin test (TST) among newly arrived asylum seekers in Norway and to assess the role of QFT in routine diagnostic screening for latent tuberculosis infection. The 1000 asylum seekers (age > or = 18 years) enrolled in the study were voluntarily recruited from 2813 consecutive asylum seekers arriving at the national reception centre from September 2005 to June 2006. Participation included a QFT test and a questionnaire in addition to the mandatory TST and chest X-ray. Among 912 asylum seekers with valid test results, 29% (264) had a positive QFT test whereas 50% (460) tested positive with TST (indurations > or = 6 mm), indicating a high proportion of latent infection within this group. Among the TST positive participants 50% were QFT negative, whereas 7% of the TST negative participants were QFT positive. There was a significant association between increase in size of TST result and the likelihood of being QFT positive. Agreement between the tests was 71-79% depending on the chosen TST cut-off and it was higher for non-vaccinated individuals. By using QFT in routine screening, further follow-up could be avoided in 43% of the asylum seekers who would have been referred if based only on a positive TST (> or = 6 mm). The proportion of individuals referred will be the same whether QFT replaces TST or is used as a supplement to confirm a positive TST, but the number tested will vary greatly. All three screening approaches would identify the same proportion (88-89%) of asylum seekers with a positive QFT and/or a TST > or = 15 mm, but different groups will be missed.


A wrapper-based approach to image segmentation and classification.
The traditional processing flow of segmentation followed by classification in computer vision assumes that the segmentation is able to successfully extract the object of interest from the background image. It is extremely difficult to obtain a reliable segmentation without any prior knowledge about the object that is being extracted from the scene. This is further complicated by the lack of any clearly defined metrics for evaluating the quality of segmentation or for comparing segmentation algorithms. We propose a method of segmentation that addresses both of these issues, by using the object classification subsystem as an integral part of the segmentation. This will provide contextual information regarding the objects to be segmented, as well as allow us to use the probability of correct classification as a metric to determine the quality of the segmentation. We view traditional segmentation as a filter operating on the image that is independent of the classifier, much like the filter methods for feature selection. We propose a new paradigm for segmentation and classification that follows the wrapper methods of feature selection. Our method wraps the segmentation and classification together, and uses the classification accuracy as the metric to determine the best segmentation. By using shape as the classification feature, we are able to develop a segmentation algorithm that relaxes the requirement that the object of interest to be segmented must be homogeneous in some low-level image parameter, such as texture, color, or grayscale. This represents an improvement over other segmentation methods that have used classification information only to modify the segmenter parameters, since these algorithms still require an underlying homogeneity in some parameter space. Rather than considering our method as, yet, another segmentation algorithm, we propose that our wrapper method can be considered as an image segmentation framework, within which existing image segmentation algorithms may be executed. We show the performance of our proposed wrapper-based segmenter on real-world and complex images of automotive vehicle occupants for the purpose of recognizing infants on the passenger seat and disabling the vehicle airbag. This is an interesting application for testing the robustness of our approach, due to the complexity of the images, and, consequently, we believe the algorithm will be suitable for many other real-world applications.


Novel insertion frameshift mutation of the LH receptor gene: problematic clinical distinction of Leydig cell hypoplasia from enzyme defects primarily affecting testosterone biosynthesis.
Leydig cell hypoplasia (LCH) is a rare autosomal recessive condition that interferes with normal development of male external genitalia in 46,XY individuals and is caused by inactivating mutations of the LH receptor gene. The clinical and biochemical diagnostic parameters of LCH are not always specific and may therefore show significant overlap with other causes of insufficient testicular steroid biosynthesis. We have studied a 46,XY newborn with completely female external genitalia and palpable testes. Due to an increased basal serum ratio of androstenedione/testosterone, 17 beta-hydroxysteroid dehydrogenase type 3 (17 beta-HSD 3) deficiency was initially suspected. DNA analysis of the corresponding HSD17B3 gene, however, showed no abnormalities in the entire coding region. In contrast, direct sequencing of the LH receptor gene revealed a novel homozygous single nucleotide insertion in exon 11 (codon A589fs) producing a frame shift in the open reading frame predicting for premature termination of translation 17 amino acids downstream. From the genetic perspective, this mutation represents the first frame shift mutation in the LH receptor gene ever reported to date. From the clinical standpoint, LCH should always be considered in the differential diagnosis as steroid profiles may not be informative. Therefore, molecular genetic analysis should be warranted for androgen biosynthesis defects in all cases.


Worldwide practices in child growth monitoring.
To describe child growth monitoring practices worldwide in preparation for the construction and application of a new international growth reference. A questionnaire was sent to Ministries of Health in 202 countries requesting information on growth charts used in national programs, reference populations, classification systems, problems encountered, and actions taken against growth faltering. Countries also provided hard copies of charts in current use. This information was entered and analyzed in Microsoft Access. Responses were received from 178 (88%) countries, 154 of which included growth charts (n=806). Two thirds of the charts covered preschool age. All countries used weight-for-age, over half relying on this index alone. The reference most commonly used (68%) was the National Center for Health Statistics/World Health Organization population, with regional variations, where most European countries used local standards. Sixty-three percent of charts classified child growth on percentiles, whereas about one fifth used z scores. Problems reported were both conceptual (eg, interpreting growth trajectories) and practical (eg, lack of equipment). The survey demonstrates that growth charts are used universally in pediatric care. The information gathered on current use and interpretation of growth charts provides important guidance for constructing and applying the new reference.


Emulated Clinical Trials from Longitudinal Real-World Data Efficiently Identify Candidates for Neurological Disease Modification: Examples from Parkinson's Disease.
Real-world healthcare data hold the potential to identify therapeutic solutions for progressive diseases by efficiently pinpointing safe and efficacious repurposing drug candidates. This approach circumvents key early clinical development challenges, particularly relevant for neurological diseases, concordant with the vision of the 21st Century Cures Act. However, to-date, these data have been utilized mainly for confirmatory purposes rather than as drug discovery engines. Here, we demonstrate the usefulness of real-world data in identifying drug repurposing candidates for disease-modifying effects, specifically candidate marketed drugs that exhibit beneficial effects on Parkinson's disease (PD) progression. We performed an observational study in cohorts of ascertained PD patients extracted from two large medical databases, Explorys SuperMart (N = 88,867) and IBM MarketScan Research Databases (N = 106,395); and applied two conceptually different, well-established causal inference methods to estimate the effect of hundreds of drugs on delaying dementia onset as a proxy for slowing PD progression. Using this approach, we identified two drugs that manifested significant beneficial effects on PD progression in both datasets: rasagiline, narrowly indicated for PD motor symptoms; and zolpidem, a psycholeptic. Each confers its effects through distinct mechanisms, which we explored via a comparison of estimated effects within the drug classification ontology. We conclude that analysis of observational healthcare data, emulating otherwise costly, large, and lengthy clinical trials, can highlight promising repurposing candidates, to be validated in prospective registration trials, beneficial against common, late-onset progressive diseases for which disease-modifying therapeutic solutions are scarce.


Theileria parva: in vitro studies on the effects of holding temperature, pH and medium on sporozoite infectivity.
The effects of holding temperature, pH and medium on the infectivity of Theileria parva sporozoites were investigated using an in vitro infectivity assay. The sporozoite infectivity lasted for 72 h at a holding temperature of 4 C but for only 24 h at 24 degrees C. Sporozoite infectivity was found to be sensitive to pH variations and sporozoites were most infective between pH 7 and pH 8. There was a significant loss in infectivity at pH 5 and infectivity was almost totally abolished at pH 9. Theileria parva sporozoites are usually held and manipulated in Eagle's minimum essential medium (MEM) with Earles' salts. In this study. Leibovitz-15 supplemented with 15% fetal bovine serum gave a significantly better infectivity than Eagle's MEM (3.8 log units versus 1.0 log units) or any other medium. The importance of proper management of the T. parva sporozoite environment in the laboratory or field is emphasized by the findings in these studies and might also explain some of the failures of vaccination when the pH of the holding medium was allowed to deteriorate.


An actin-dependent step in mitochondrial fission mediated by the ER-associated formin INF2.
Mitochondrial fission is fundamentally important to cellular physiology. The dynamin-related protein Drp1 mediates fission, and interaction between mitochondrion and endoplasmic reticulum (ER) enhances fission. However, the mechanism for Drp1 recruitment to mitochondria is unclear, although previous results implicate actin involvement. Here, we found that actin polymerization through ER-localized inverted formin 2 (INF2) was required for efficient mitochondrial fission in mammalian cells. INF2 functioned upstream of Drp1. Actin filaments appeared to accumulate between mitochondria and INF2-enriched ER membranes at constriction sites. Thus, INF2-induced actin filaments may drive initial mitochondrial constriction, which allows Drp1-driven secondary constriction. Because INF2 mutations can lead to Charcot-Marie-Tooth disease, our results provide a potential cellular mechanism for this disease state.


A Systematic Review of Direct Outputs from the Cerebellum to the Brainstem and Diencephalon in Mammals.
The cerebellum is involved in many motor, autonomic and cognitive functions, and new tasks that have a cerebellar contribution are discovered on a regular basis. Simultaneously, our insight into the functional compartmentalization of the cerebellum has markedly improved. Additionally, studies on cerebellar output pathways have seen a renaissance due to the development of viral tracing techniques. To create an overview of the current state of our understanding of cerebellar efferents, we undertook a systematic review of all studies on monosynaptic projections from the cerebellum to the brainstem and the diencephalon in mammals. This revealed that important projections from the cerebellum, to the motor nuclei, cerebral cortex, and basal ganglia, are predominantly di- or polysynaptic, rather than monosynaptic. Strikingly, most target areas receive cerebellar input from all three cerebellar nuclei, showing a convergence of cerebellar information at the output level. Overall, there appeared to be a large level of agreement between studies on different species as well as on the use of different types of neural tracers, making the emerging picture of the cerebellar output areas a solid one. Finally, we discuss how this cerebellar output network is affected by a range of diseases and syndromes, with also non-cerebellar diseases having impact on cerebellar output areas.


Comparison of Retrograde Intrarenal Surgery and Percutaneous Nephrolithotomy: From the View of an Anesthesiologist.
To determine the differences among the hemodynamics, neuroendocrine stress response (NESR), and postoperative visual analogue scale (VAS) scores of pain between the procedures of retrograde intrarenal surgery (RIRS) and percutaneous nephrolithotomy (PNL) for lower pole kidney stones. Fifty-six patients undergoing RIRS and PNL with lower puncture approach, under general anesthesia, were prospectively enrolled in our study. Perioperative blood pressure (systolic, diastolic, and mean), heart rate, and peripheral oxygen saturation (SpO2) values were recorded at intervals. Arterial blood gas (ABG) and blood glucose, serum insulin, and cortisol levels as stress response markers were analyzed in the perioperative period. Postoperative VAS scores were recorded at 30 minutes and 2, 4, 6, and 12 hours after extubation. Duration of surgery, stone sizes, and stone-free rates (SFRs) were noted. SFRs were 93.3% in the PNL group (28/30 patients) and 88.5% in the RIRS group (23/26 patients) (p = 0.52). There was no statistical difference between the hemodynamics of both groups. Perioperative ABGs and NESRs were similar between groups (p > 0.05). Postoperative VAS scores and analgesic consumptions were also similar between groups (p > 0.05). Duration of surgery was significantly shorter in the RIRS group (p = 0.001). Stone size was significantly higher in the PNL group (p = 0.013). Although the PNL is assumed to be more invasive than the RIRS procedure among urologists and anesthesiologists, both techniques may have similar perioperative outcomes in terms of hemodynamics, ABG, NESR, and pain scores in the management of lower pole stones with lower pole approach.


Dizziness: Approach to Evaluation and Management.
Dizziness is a common yet imprecise symptom. It was traditionally divided into four categories based on the patient's history: vertigo, presyncope, disequilibrium, and light-headedness. However, the distinction between these symptoms is of limited clinical usefulness. Patients have difficulty describing the quality of their symptoms but can more consistently identify the timing and triggers. Episodic vertigo triggered by head motion may be due to benign paroxysmal positional vertigo. Vertigo with unilateral hearing loss suggests Meniere disease. Episodic vertigo not associated with any trigger may be a symptom of vestibular neuritis. Evaluation focuses on determining whether the etiology is peripheral or central. Peripheral etiologies are usually benign. Central etiologies often require urgent treatment. The HINTS (head-impulse, nystagmus, test of skew) examination can help distinguish peripheral from central etiologies. The physical examination includes orthostatic blood pressure measurement, a full cardiac and neurologic examination, assessment for nystagmus, and the Dix-Hallpike maneuver. Laboratory testing and imaging are not required and are usually not helpful. Benign paroxysmal positional vertigo can be treated with a canalith repositioning procedure (e.g., Epley maneuver). Treatment of Meniere disease includes salt restriction and diuretics. Symptoms of vestibular neuritis are relieved with vestibular suppressant medications and vestibular rehabilitation.


Ruxolitinib: a new treatment for myelofibrosis.
Myelofibrosis (MF) is a blood cancer characterized by fibrotic bone marrow and altered hematopoiesis. Although the prevalence of MF is low, its severe symptoms have a significantly negative impact on patient quality of life, and its ability to transform into leukemia increases morbidity. Conventional drug therapies provide modest symptom palliation, but allogeneic stem cell transplantation has been the only treatment capable of affecting MF's natural history. Ruxolitinib (Jakafi®) is a new targeted therapy indicated to treat patients with intermediate- and high-risk MF. Although the research is conflicted regarding ruxolitinib's ability to affect survival or induce remission, studies show that it offers dramatic improvements in symptom management. However, ruxolitinib carries some potentially life-threatening adverse effects. This article reviews ruxolitinib, discusses its risks and benefits, and describes the vital role of oncology nurses in education, monitoring, and support.


Cytosine Methylation Affects the Mutability of Neighboring Nucleotides in Germline and Soma.
Methylated cytosines deaminate at higher rates than unmethylated cytosines, and the lesions they produce are repaired less efficiently. As a result, methylated cytosines are mutational hotspots. Here, combining rare polymorphism and base-resolution methylation data in humans, Arabidopsis thaliana, and rice (Oryza sativa), we present evidence that methylation state affects mutation dynamics not only at the focal cytosine but also at neighboring nucleotides. In humans, contrary to prior suggestions, we find that nucleotides in the close vicinity (±3 bp) of methylated cytosines mutate less frequently. Reduced mutability around methylated CpGs is also observed in cancer genomes, considering single nucleotide variants alongside tissue-of-origin-matched methylation data. In contrast, methylation is associated with increased neighborhood mutation risk in A. thaliana and rice. The difference in neighborhood mutation risk is less pronounced further away from the focal CpG and modulated by regional GC content. Our results are consistent with a model where altered risk at neighboring bases is linked to lesion formation at the focal CpG and subsequent long-patch repair. Our findings indicate that cytosine methylation has a broader mutational footprint than is commonly assumed.


Investigation of ablation thresholds of optical materials using 1-µm-focusing beam at hard X-ray free electron laser.
We evaluated the ablation thresholds of optical materials by using hard X-ray free electron laser. A 1-µm-focused beam with 10-keV of photon energy from SPring-8 Angstrom Compact free electron LAser (SACLA) was irradiated onto silicon and SiO2 substrates, as well as the platinum and rhodium thin films on these substrates, which are widely used for optical materials such as X-ray mirrors. We designed and installed a dedicated experimental chamber for the irradiation experiments. For the silicon substrate irradiated at a high fluence, we observed strong mechanical cracking at the surface and a deep ablation hole with a straight side wall. We confirmed that the ablation thresholds of uncoated silicon and SiO2 substrates agree with the melting doses of these materials, while those of the substrates under the metal coating layer are significantly reduced. The ablation thresholds obtained here are useful criteria in designing optics for hard X-ray free electron lasers.


Preclinical antitumor activity of bizelesin in mice.
Bizelesin (U-77779, NSC 615291), a synthetic analogue of the cytotoxic antibiotic CC-1065, is a bifunctional alkylating agent that produces DNA interstrand cross-links. Bizelesin was evaluated for antitumor activity against a broad spectrum of syngeneic murine tumors and human tumor xenografts in mice. Systemic drug administration produced >6.7 log10 cell kill against i.p. implanted P388 and L1210 leukemias and 80% tumor-free survivors against s.c. implanted L1210. Against i.p. implanted B16 melanoma, i.p. drug administration produced a 158%; increase in life span with 25% tumor-free survivors, whereas i.v. drug administration produced only a 67% increase in life span with no tumor-free survivors. More than 1.0 log10 cell kill was observed at low microgram/kg doses in several human tumor models representing diverse histiotypes (CAKI-1 renal, LX-1 lung, HT-29 colon, LOX IMVI and UACC-62 melanomas, and MX-1 mammary). Less than 1.0 log10 cell kill was exhibited in other tumor models (Lewis lung, colon 38, pancreatic 02, MCF7 mammary, and SK-MEL-3 melanoma). Bizelesin was optimally active when administered i.v. Although antitumor activity was independent of the schedule of administration, greater total doses were tolerated on the more prolonged schedules in any given experiment. Therapeutic doses of bizelesin did not produce delayed deaths, which had previously been observed for the parent compound CC-1065. However, recovery of lost weight was not attained until 16-30 days posttherapy. Bizelesin was as active against murine leukemia sublines resistant to cisplatin, melphalan, and 1,3-bis-(2-chloroethyl)-1-nitrosourea as against the parental line but was totally inactive against a doxorubicin-resistant subline. The complete cross-resistance of the doxorubicin-resistant subline to bizelesin suggests that bizelesin may be a substrate for the efflux pump that causes multidrug resistance. Due to its breadth of antitumor activity, potency, unique mechanism of action, and lack of cross-resistance with other alkylating agents, bizelesin was selected for development in clinical trials by the National Cancer Institute and the Upjohn Company. Toxicological studies and pharmaceutical development have been completed, and clinical trials are planned to start in the summer of 1996.


Advances in lead-free double perovskite nanocrystals, engineering band-gaps and enhancing stability through composition tunability.
In this topical review, we have focused on the recent advances made in the studies of lead-free perovskites in the bulk form and as nanocrystals. Substitution of lead in halide perovskites is essential to overcome the toxicity concerns and improve the relatively low stability of these materials. In lead-free double perovskites the unit cell is doubled and two divalent lead cations are replaced by mono and trivalent cations. The current main challenge with the double perovskite metal halides lies in overcoming their inherently indirect and disallowed optical transitions. In this review, we have discussed the recent discoveries made in the synthesis of these materials and highlighted how nanocrystals can serve as model systems to explore the schemes of cationic exchange, doping and alloying for engineering the electronic structure of double perovskites. In nanocrystals, the quantum confinement effects can modify the electronic structure and the resulting optical transition, thus increasing the absorption cross-section and emission, which are important properties for optoelectronic devices. Lastly, the enlarged surface to volume ratio in the nanocrystals adds a surface energy term that may enhance the stability of the metastable crystallographic phases. We have reviewed how the nanocrystal can provide information on phases that are inherently stable and investigated how the facile exchange reactions can help in achieving material compositions that are impossible to achieve by any other way. Finally, based on our recent synthetic experience, we have emphasized the similarities between lead-based and lead-free perovskite nanocrystals; we hope that our insight along with a summary of recent progress in this fast-growing field will help to expand the interest in lead-free perovskites towards a greener and brighter future.


Identification and characterization of microRNAs in pearl oyster Pinctada martensii by Solexa deep sequencing.
MicroRNAs (miRNAs) are short-nucleotide RNA molecules that function as negative regulators of gene expression in various organisms. However, miRNAs of Pinctada martensii have not been reported yet. P. martensii is one of the main species cultured for marine pearl production in China and Japan. In order to obtain the repertoire of miRNAs in P. martensii, we constructed and sequenced small RNA libraries prepared from P. martensii by Solexa deep sequencing technology and got a total of 27,479,838 reads representing 3,176,630 distinct sequences. After removing tRNAs, rRNAs, snRNAs, and snoRNAs, 10,596,306 miRNA reads representing 18,050 distinct miRNA reads were obtained. Based on sequence similarity and hairpin structure prediction, 258 P. martensii miRNAs (pm-miRNA) were identified. Among these pm-miRNAs, 205 were conserved across the species, whereas 53 were specific for P. martensii. The 3' end sequence of U6 snRNA was obtained from P. martensii by 3' rapid amplification of cDNA end PCR reaction and sequence-directed cloning. Eight conserved pm-miRNAs and two novel pm-miRNAs were validated by stem-loop quantitative real-time PCR with U6 snRNA as an internal reference gene. pm-miRNAs and the reported biomineralization-related genes were subjected to target analysis by using target prediction tools. Some of the pm-miRNAs, such as miR-2305 and miR-0046, were predicted to participate in biomineralization by regulating the biomineralization-related genes. Thus, this study demonstrated a large-scale characterization of pm-miRNAs and their potential function in biomineralization, providing a foundation to understand shell formation.


History of oilseed rape cropping and geographic origin affect the genetic structure of Plasmodiophora brassicae populations.
The soilborne pathogen Plasmodiophora brassicae causes clubroot on Brassica crops, a common disease in many oilseed rape growing regions. Here, we investigate genetic diversity and geographic differentiation of P. brassicae populations from different regions in Germany. We compared three regions that differ in oilseed rape cropping history, oilseed rape acreage, and incidence of clubroot. These regions were either spatially separated or separated by the former inner German border. Plasmodiophora isolates were collected from 59 fields (29, 17, and 13 fields per region, respectively) and 174 amplified fragment length polymorphism (AFLP) markers were analyzed. Every field isolate showed a unique genotype pattern; that is, no genotype was shared among the regions and different fields. The mean gene diversity was 0.27, suggesting that P. brassicae is a genetically diverse species. The comparison of indexes (gene diversity, genotypic diversity, and linkage disequilibrium) between the regions does not support our hypotheses that cropping history, oilseed rape acreage, and incidence of clubroot affect these estimates. Principal component analysis (PCA), fixation index (FST), and generalized linear model (GLM) were suitable to specify regional differences. PCA revealed two clusters of isolates based on the geographic origin of the isolates and FST showed that these clusters were highly differentiated. Hypotheses about association of genotypes with different spatial scales were tested with GLM: the region, reflecting the cropping history, and the individual field had a significant effect on the AFLP pattern. We propose that individual field isolates represent a discrete population and that geographic differentiation results from low levels of gene flow due to the limited dispersal of this soilborne pathogen and from localized selection pressure as unifying force on the genotypes.


Cytotoxicity and genotoxicity assessment of silver nanoparticles in mouse.
Silver nanoparticles (AgNPs) are among the most commercially used nanomaterials and their toxicity and genotoxicity are controversial. Although many in vitro studies have been conducted to evaluate the genotoxicity of AgNPs, in vivo genotoxicity studies on the nanomaterials are limited. Given the unique physicochemical properties and complex pharmacokinetics behavior of nanoparticles (NPs), in vivo genotoxicity assessment of AgNPs is badly needed. In this study, the clastogenicity and mutagenicity of AgNPs with different sizes and coatings were evaluated using mouse micronucleus (MN) assay, Pig-a assay and Comet assay. Five 7-week-old male B6C3F1 mice per group were treated with 5 nm polyvinylpyrrolidone (PVP)-coated AgNPs at a single dose of 0.5, 1.0, 2.5, 5.0, 10.0 or 20.0 mg/kg body weight (bw) via intravenous injection for both the MN and Pig-a assays; or with 15-100 nm PVP- or 10-80 nm silicon-coated AgNPs at a single or 3-day repeated dose of 25.0 mg/kg bw for the MN assay and Comet assay in mouse liver. Inductively coupled plasma mass spectrometry (ICP-MS) and transmission electron microscopy (TEM) analyses indicated that AgNPs reached the testing tissues (bone marrow for the MN and Pig-a assays and liver for the Comet assay). Although there was a reduction of reticulocytes in the PVP-coated AgNPs-treated animals, indicating cytotoxicity of the AgNPs, none of the treatments resulted in a significant increase of either mutant frequencies in the Pig-a gene or the percent of micronucleated reticulocyte over the concurrent controls. However, both the PVP- and silicon-coated AgNPs induced oxidative DNA damage in mouse liver. These results demonstrate that the AgNPs can reach mouse bone marrow and liver, and generate cytotoxicity to the reticulocytes and oxidative DNA damage to the liver.


Collagen and tissue turnover as a function of age: Implications for fibrosis.
The extracellular matrix (ECM) is the backbone of all tissues. It is a complex grid consisting of multiple structural proteins which each play a vital role for the function and maintenance of normal tissue function. In development and growth, tissue is being formed and elaborated (tissue modeling), while in adult life, tissues are being maintained and remodeled. These processes involve likely different mechanisms. During tissue modeling and remodeling, small fragments of proteins are released into the circulation, where they may be used as biomarkers for tissue turnover. The aim of the study was to investigate ECM turnover in rodents as a function of age. Serum of rats of 1, 2, 3, 4, 5, 6, 10 and 12months of age was profiled for 15 markers of ECM turnover, including: fragments of type I, II, III, IV, V and VI collagen formation (P1NP, P4NP-7S, Pro-C5, Pro-C6) and degradation (C1M, C2M, C2M-beta, C3M, C4M, C5M, C6M); biglycan (BGM) and elastin (ELM7) degradation; and the type I and II collagen telopeptides CTX-I and CTX-II. Type I and II collagen turnover was up to 93% and 97% downregulated in old (one year) compared to young (one month) old animals (p<0.0001), while type IV and V collagen and biglycan turnover was upregulated 2.5-, 2- and 2-fold, respectively (p<0.0001). Type III and VI collagen and elastin turnover was not influenced significantly by age. ECM turnover rates were consistently different in young vs. old animals, up to 30 fold. This appears to be due to body growth, a different ECM composition and a higher regenerative capability of connective tissues in young vs. old animals. These changes have to be accounted for in translational science. Both in measuring serum levels of ECM biomarkers and in the development of therapies to speed up wound healing or inhibit fibrogenesis.


Perspective: Defining and quantifying the role of dynamics in enzyme catalysis.
Enzymes control chemical reactions that are key to life processes, and allow them to take place on the time scale needed for synchronization between the relevant reaction cycles. In addition to general interest in their biological roles, these proteins present a fundamental scientific puzzle, since the origin of their tremendous catalytic power is still unclear. While many different hypotheses have been put forward to rationalize this, one of the proposals that has become particularly popular in recent years is the idea that dynamical effects contribute to catalysis. Here, we present a critical review of the dynamical idea, considering all reasonable definitions of what does and does not qualify as a dynamical effect. We demonstrate that no dynamical effect (according to these definitions) has ever been experimentally shown to contribute to catalysis. Furthermore, the existence of non-negligible dynamical contributions to catalysis is not supported by consistent theoretical studies. Our review is aimed, in part, at readers with a background in chemical physics and biophysics, and illustrates that despite a substantial body of experimental effort, there has not yet been any study that consistently established a connection between an enzyme's conformational dynamics and a significant increase in the catalytic contribution of the chemical step. We also make the point that the dynamical proposal is not a semantic issue but a well-defined scientific hypothesis with well-defined conclusions.


Major depression and first-time hospitalization with ischemic heart disease, cardiac procedures and mortality in the general population: a retrospective Danish population-based cohort study.
We investigated the association between unipolar depression and incident hospital admissions due to ischemic heart disease, invasive cardiac procedures and mortality independent of other medical illnesses. A population-based cohort of 4.6 million persons aged 15 years or older and born in Denmark was followed up from 1995-2009. Incidence rate ratio (IRR) and mortality rate ratio (MRR) were estimated by survival analysis, stratified by or adjusted for gender, age, severe chronic somatic comorbidity and calendar time. Adjusted risks of cardiac hospital admissions and death were significantly increased by up to 15% and 68%, respectively, in persons with hospital admissions due to depression, and were most increased in 15-59 year old women (IRR: 1.64; MRR: 2.57) and men with depression (IRR: 1.39; MRR: 2.21), and during the first 180 days after being diagnosed with depression (women: IRR: 1.38; MRR: 2.35; men: IRR: 1.42; MRR: 2.67). One-year mortality after new ischemic heart disease was elevated by 34% in women and men. By contrast, overall rates of invasive cardiac procedures following cardiac hospitalizations were significantly decreased by 34% in persons with depression but were twofold increased in men recently diagnosed with depression. Clinical depression leading to hospitalization was a risk factor for new cardiac complications independent of somatic comorbidity in the magnitude of other cardiac risk factors, particularly in individuals between 15-59 years of age and during the first weeks following psychiatric admission. Our findings support recent cardiovascular disease prevention guidelines on assessing depression among other psychosocial factors in patients at increased cardiovascular disease (CVD) risk.


Circuit oxygenator contributes to extracorporeal membrane oxygenation-induced hemolysis.
Hemolysis can occur as a consequence of extracorporeal membrane oxygenation (ECMO) and is associated with increased mortality and morbidity. Shear stress generated by flow through the circuit and oxygenator is believed to cause ECMO-induced hemolysis. We hypothesize that either a smaller dimension oxygenator or an in-line hemofilter will increase ECMO-associated hemolysis. Circuits were configured with a Quadrox-D Adult oxygenator (surface area 1.8 m), Quadrox-iD Pediatric oxygenator (surface area 0.8 m), or Quadrox-D Adult oxygenator with an in-line hemofilter (N = 4) and ran for 6 hours. Samples were collected hourly from the ECMO circuit and a time-based hemolysis control. Plasma hemoglobin levels were assayed. Circuit-induced hemolysis at each time point was defined as the change in plasma hemoglobin standardized to the time-based hemolysis control. Plasma hemoglobin increased with the use of the smaller dimension pediatric oxygenator as compared with the adult oxygenator when controlling for ECMO run time (p = 0.02). Furthermore, there was a greater pressure gradient with the smaller dimension pediatric oxygenator (p < 0.05). Plasma hemoglobin did not change with the addition of the in-line hemofilter. The use of a smaller dimension pediatric oxygenator resulted in greater hemolysis and a higher pressure gradient. This may indicate that the increased shear forces augment ECMO-induced hemolysis.