Reinforcement learning in continuous time and space.
This article presents a reinforcement learning framework for continuous-time dynamical systems without a priori discretization of time, state, and action. Based on the Hamilton-Jacobi-Bellman (HJB) equation for infinite-horizon, discounted reward problems, we derive algorithms for estimating value functions and improving policies with the use of function approximators. The process of value function estimation is formulated as the minimization of a continuous-time form of the temporal difference (TD) error. Update methods based on backward Euler approximation and exponential eligibility traces are derived, and their correspondences with the conventional residual gradient, TD(0), and TD(lambda) algorithms are shown. For policy improvement, two methods-a continuous actor-critic method and a value-gradient-based greedy policy-are formulated. As a special case of the latter, a nonlinear feedback control law using the value gradient and the model of the input gain is derived. The advantage updating, a model-free algorithm derived previously, is also formulated in the HJB-based framework. The performance of the proposed algorithms is first tested in a nonlinear control task of swinging a pendulum up with limited torque. It is shown in the simulations that (1) the task is accomplished by the continuous actor-critic method in a number of trials several times fewer than by the conventional discrete actor-critic method; (2) among the continuous policy update methods, the value-gradient-based policy with a known or learned dynamic model performs several times better than the actor-critic method; and (3) a value function update using exponential eligibility traces is more efficient and stable than that based on Euler approximation. The algorithms are then tested in a higher-dimensional task: cart-pole swing-up. This task is accomplished in several hundred trials using the value-gradient-based policy with a learned dynamic model.


Customizable 3D printed perfusion bioreactor for the engineering of stem cell microenvironments.
Faithful modeling of tissues and organs requires the development of systems reflecting their dynamic 3D cellular architecture and organization. Current technologies suffer from a lack of design flexibility and complex prototyping, preventing their broad adoption by the scientific community. To make 3D cell culture more available and adaptable we here describe the use of the fused deposition modeling (FDM) technology to rapid-prototype 3D printed perfusion bioreactors. Our 3D printed bioreactors are made of polylactic acid resulting in reusable systems customizable in size and shape. Following design confirmation, our bioreactors were biologically validated for the culture of human mesenchymal stromal cells under perfusion for up to 2 weeks on collagen scaffolds. Microenvironments of various size/volume (6-12 mm in diameter) could be engineered, by modulating the 3D printed bioreactor design. Metabolic assay and confocal microscopy confirmed the homogenous mesenchymal cell distribution throughout the material pores. The resulting human microenvironments were further exploited for the maintenance of human hematopoietic stem cells. Following 1 week of stromal coculture, we report the recapitulation of 3D interactions between the mesenchymal and hematopoietic fractions, associated with a phenotypic expansion of the blood stem cell populations.Our data confirm that perfusion bioreactors fit for cell culture can be generated using a 3D printing technology and exploited for the 3D modeling of complex stem cell systems. Our approach opens the gates for a more faithful investigation of cellular processes in relation to a dynamic 3D microenvironment.


Microplastic pollution in deposited urban dust, Tehran metropolis, Iran.
Environmental pollutants such as microplastics have become a major concern over the last few decades. We investigated the presence, characteristics, and potential health risks of microplastic dust ingestion. The plastic load of 88 to 605 microplastics per 30 g dry dust with a dominance of black and yellow granule microplastics ranging in size from 250 to 500 μm was determined in 10 street dust samples using a binocular microscope. Fluorescence microscopy was found to be ineffective for detecting and counting plastic debris. Scanning electron microscopy, however, was useful for accurate detection of microplastic particles of different sizes, colors, and shapes (e.g., fiber, spherule, hexagonal, irregular polyhedron). Trace amounts of Al, Na, Ca, Mg, and Si, detected using energy dispersive X-ray spectroscopy, revealed additives of plastic polymers or adsorbed debris on microplastic surfaces. As a first step to estimate the adverse health effects of microplastics in street dust, the frequency of microplastic ingestion per day/year via ingestion of street dust was calculated. Considering exposure during outdoor activities and workspaces with high abundant microplastics as acute exposure, a mean of 3223 and 1063 microplastic particles per year is ingested by children and adults, respectively. Consequently, street dust is a potentially important source of microplastic contamination in the urban environment and control measures are required.


Estimating the economic impact of Trypanosoma evansi infection on production of camel herds in Somaliland.
The traditional livestock sector in Somalia is based on nomadic pastoralism where sheep, goats and camels are herded in large numbers. Data from 1609 females (27 % lactating) and 550 males (26 % exported) belonging to 40 pastoralists were analysed in this study. The expected amount of revenue the herders could lose per year in the studied area was estimated at US$404,630 being made up of US$314,630 from decreased milk yield and US$90,000 from reduced market value of exported animals. However, all the camels in Somaliland are at risk of acquiring surra infection, and therefore extrapolating the current findings to the total population could potentially lose US$223,164,000. This highlights the loss in the magnitude of US$164,253,600 from decreased milk yield and US$58,910,400 from body condition loss. Overall, the benefit in controlling Trypanosoma evansi infection in the study area was US$398,880 (n = 2159). On average, US$720 was saved per head per year from improved milk production in treated animals and US$615 from the increased value of exported camels. It is concluded that all three-treatment options evaluated were economically beneficial strategies; however, the biannual treatment of seropositive camels in the herds was the best financial option.


Mucormycosis.
The term mucormycosis encompasses a distinctive group of infections caused by fungi belonging to genera within the taxonomic order Mucorales, usually Rhizopus, Absidia, Mortierella, and Mucor. These fungi are widespread in nature, subsisting on decaying vegetation and diverse organic materials. Although the fungi and spores of Mucorales show minimal intrinsic pathogenicity toward normal persons, they can initiate aggressive and fulminant infections under certain clinical conditions. Ketoacidotic diabetics are predisposed to rhinocerebral mucormycosis, whereas patients with leukemia or lymphoma are susceptible to pulmonary or disseminated infections. These infections, which often result in devastating long-term sequelae for surviving patients, pose difficult diagnostic and therapeutic challenges.


Thiamine and benfotiamine counteract ultrasound-induced aggression, normalize AMPA receptor expression and plasticity markers, and reduce oxidative stress in mice.
The negative societal impacts associated with the increasing prevalence of violence and aggression is increasing, and, with this rise, is the need to understand the molecular and cellular changes that underpin ultrasound-induced aggressive behavior. In mice, stress-induced aggression is known to alter AMPA receptor subunit expression, plasticity markers, and oxidative stress within the brain. Here, we induced aggression in BALB/c mice using chronic ultrasound exposure and examined the impact of the psychoactive anti-oxidant compounds thiamine (vitamin B1), and its derivative benfotiamine, on AMPA receptor subunit expression, established plasticity markers, and oxidative stress. The administration of thiamine or benfotiamine (200 mg/kg/day) in drinking water decreased aggressive behavior following 3-weeks of ultrasound exposure and benfotiamine, reduced floating behavior in the swim test. The vehicle-treated ultrasound-exposed mice exhibited increases in protein carbonyl and total glutathione, altered AMPA receptor subunits expression, and decreased expression of plasticity markers. These ultrasound-induced effects were ameliorated by thiamine and benfotiamine treatment; in particular both antioxidants were able to reverse ultrasound-induced changes in GluA1 and GluA2 subunit expression, and, within the prefrontal cortex, significantly reversed the changes in protein carbonyl and polysialylated form of neural cell adhesion molecule (PSA-NCAM) expression levels. Benfotiamine was usually more efficacious than thiamine. Thus, the thiamine compounds were able to counteract ultrasound-induced aggression, which was accompanied by the normalization of markers that have been showed to be associated with ultrasound-induced aggression. These commonly used, orally-active compounds may have considerable potential for use in the control of aggression within the community. This article is part of the Special Issue entitled 'Current status of the neurobiology of aggression and impulsivity'.


Pregnancy in a healthy woman with untreated citrullinemia.
We report the clinical and biochemical data on a second successful pregnancy in a woman with citrullinemia due to argininosuccinate synthetase deficiency (CTLN1). Despite very elevated plasma and urine citrulline and little or no measurable argininosuccinate synthetase enzyme activity on cultured skin fibroblasts, this 29-year-old woman, who was identified through newborn screening, has remained asymptomatic throughout her life. Mutation analysis has recently revealed that she is a compound heterozygote for a known and a novel mutation (IVS15-1G > C and K310Q, respectively). Many newborn screening programs have recently been expanded to include citrullinemia and numerous asymptomatic hypercitrullinemic infants and children have been identified. It is now important to define prognostic indicators that will help with treatment decisions and genetic counseling for these patients. This patient, as the only citrullinemic adult who has been followed prospectively, contributes important information in this regard. In addition, her child was unaffected by the high citrulline levels demonstrated in amniotic fluid and breast milk suggesting that citrulline is not teratogenic. Although pregnancy is an important risk factor for women with CTLN1, it appears that females with citrullinemia can have normal pregnancy outcomes, as long as metabolic crisis is avoided.


Recent advances of pharmacogenomics in severe cutaneous adverse reactions: immune and nonimmune mechanisms.
Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), and drug reaction with eosinophilia and systemic symptoms (DRESS) are severe cutaneous adverse reactions (SCAR) which are majorly caused by drugs. Though the incidence rate is low, SCAR sometimes can be life-threatening and leads to lifelong sequelae. Many pharmacogenomic associations in immune and nonimmune related genes with the development of SCAR have been discovered recently and the pharmacogenetic tests have been applied to prevent specific drug-induced SCAR. In this review, we discuss the recent advances of pharmacogenomics in SCAR.


Mouse model of SARS-CoV-2 reveals inflammatory role of type I interferon signaling.
Severe Acute Respiratory Syndrome- Coronavirus 2 (SARS-Cov-2) has caused over 5,000,000 cases of Coronavirus disease (COVID-19) with significant fatality rate.1-3 Due to the urgency of this global pandemic, numerous therapeutic and vaccine trials have begun without customary safety and efficacy studies.4 Laboratory mice have been the stalwart of these types of studies; however, they do not support infection by SARS-CoV-2 due to the inability of its spike (S) protein to engage the mouse ortholog of its human entry receptor angiotensin-converting enzyme 2 (hACE2). While hACE2 transgenic mice support infection and pathogenesis,5 these mice are currently limited in availability and are restricted to a single genetic background. Here we report the development of a mouse model of SARS-CoV-2 based on adeno associated virus (AAV)-mediated expression of hACE2. These mice support viral replication and antibody production and exhibit pathologic findings found in COVID-19 patients as well as non-human primate models. Moreover, we show that type I interferons are unable to control SARS-CoV2 replication and drive pathologic responses. Thus, the hACE2-AAV mouse model enables rapid deployment for in-depth analysis following robust SARS-CoV-2 infection with authentic patient-derived virus in mice of diverse genetic backgrounds. This represents a much-needed platform for rapidly testing prophylactic and therapeutic strategies to combat COVID-19.


Kinetic and spectroscopic studies of hemin acquisition in the hemophore HasAp from Pseudomonas aeruginosa.
The extreme limitation of free iron has driven various pathogens to acquire iron from the host in the form of heme. Specifically, several Gram-negative pathogens secrete a heme binding protein known as HasA to scavenge heme from the extracellular environment and to transfer it to the receptor protein HasR for import into the bacterial cell. Structures of heme-bound and apo-HasA homologues show that the heme iron(III) ligands, His32 and Tyr75, reside on loops extending from the core of the protein and that a significant conformational change must occur at the His32 loop upon heme binding. Here, we investigate the kinetics of heme acquisition by HasA from Pseudomonas aeruginosa (HasAp). The rate of heme acquisition from human met-hemoglobin (met-Hb) closely matches that of heme dissociation which suggests a passive mode of heme uptake from this source. The binding of free hemin is characterized by an initial rapid phase forming an intermediate before further conversion to the final complex. Analysis of this same reaction using an H32A variant lacking the His heme ligand shows only the rapid phase to form a heme-protein complex spectroscopically equivalent to that of the wild-type intermediate. Further characterization of these reactions using electron paramagnetic resonance and resonance Raman spectroscopy of rapid freeze quench samples provides support for a model in which heme is initially bound by the Tyr75 to form a high-spin heme-protein complex before slower coordination of the His32 ligand upon closing of the His loop over the heme. The slow rate of this loop closure implies that the induced-fit mechanism of heme uptake in HasAp is not based on a rapid sampling of the H32 loop between open and closed configurations but, rather, that the H32 loop motions are triggered by the formation of the high-spin heme-HasAp intermediate complex.


Performance of a limiting-antigen avidity enzyme immunoassay for cross-sectional estimation of HIV incidence in the United States.
A limiting antigen avidity enzyme immunoassay (HIV-1 LAg-Avidity assay) was recently developed for cross-sectional HIV incidence estimation. We evaluated the performance of the LAg-Avidity assay alone and in multi-assay algorithms (MAAs) that included other biomarkers. Performance of testing algorithms was evaluated using 2,282 samples from individuals in the United States collected 1 month to >8 years after HIV seroconversion. The capacity of selected testing algorithms to accurately estimate incidence was evaluated in three longitudinal cohorts. When used in a single-assay format, the LAg-Avidity assay classified some individuals infected >5 years as assay positive and failed to provide reliable incidence estimates in cohorts that included individuals with long-term infections. We evaluated >500,000 testing algorithms, that included the LAg-Avidity assay alone and MAAs with other biomarkers (BED capture immunoassay [BED-CEIA], BioRad-Avidity assay, HIV viral load, CD4 cell count), varying the assays and assay cutoffs. We identified an optimized 2-assay MAA that included the LAg-Avidity and BioRad-Avidity assays, and an optimized 4-assay MAA that included those assays, as well as HIV viral load and CD4 cell count. The two optimized MAAs classified all 845 samples from individuals infected >5 years as MAA negative and estimated incidence within a year of sample collection. These two MAAs produced incidence estimates that were consistent with those from longitudinal follow-up of cohorts. A comparison of the laboratory assay costs of the MAAs was also performed, and we found that the costs associated with the optimal two assay MAA were substantially less than with the four assay MAA. The LAg-Avidity assay did not perform well in a single-assay format, regardless of the assay cutoff. MAAs that include the LAg-Avidity and BioRad-Avidity assays, with or without viral load and CD4 cell count, provide accurate incidence estimates.


Mathematical models of folate-mediated one-carbon metabolism.
Folate-mediated one-carbon metabolism is an unusually complex metabolic network, consisting of several interlocking cycles, and compartmentation between cytosol and mitochondria. The cycles have diverse functions, the primary being thymidylate synthesis (the rate limiting step in DNA synthesis), the initial steps in purine synthesis, glutathione synthesis, and a host of methyl transfer reactions that include DNA and histone methylation. Regulation within the network is accomplished by numerous allosteric interactions in which metabolites in one part of the network affect the activity of enzymes elsewhere in the network. Although a large body of experimental work has elucidated the details of the mechanisms in every part of the network, the multitude of complex and non-linear interactions within the network makes it difficult to deduce how the network as a whole operates. Understanding the operation of this network is further complicated by the fact that human populations maintain functional polymorphisms for several enzymes in the network, and that the network is subject to continual short and long-term fluctuations in its inputs as well as in demands on its various outputs. Understanding how such a complex system operates is possible only by means of mathematical models that take account of all the reactions and interactions. Simulations with such models can be used as an adjunct to laboratory experimentation to test ideas and alternative hypotheses and interpretations quickly and inexpensively. A number of mathematical models have been developed over the years, largely motivated by the need to understand the complex mechanisms by which anticancer drugs like methotrexate inhibit nucleotide synthesis and thus limit the ability of cells to divide. More recently, mathematical models have been used to investigate the regulatory and homeostatic mechanisms that allow the system to accommodate large fluctuations in one part of the network without affecting critical functions elsewhere in the network.


Increasing frequency of staphylococcal infective endocarditis. Experience at a university hospital, 1981 through 1988.
To determine the characteristics of infective endocarditis in our hospital, we reviewed all patients with that diagnosis at the University of Massachusetts Medical Center, Worcester, between 1981 and 1988. Of 113 patients with infective endocarditis, 56 (50%) had staphylococcal endocarditis. Despite aggressive medical and surgical therapy, in-hospital mortality was 25%. Forty-five (80%) of the 56 cases of staphylococcal endocarditis involved Staphylococcus aureus with a mortality of 28% vs 9% in the non-S aureus group. Mortality was higher in patients with congestive heart failure (35%), atrioventricular block (45%), atrial fibrillation (42%), and prosthetic valve endocarditis (50%). Seventy-six percent of the patients with congestive heart failure required surgery. Patients with congestive heart failure and S aureus infection had a mortality of 45%. Thirty-six patients (64%) were alive at late follow-up (mean, 28.6 months). Mortality was highest (23%) during the first 3 months following diagnosis of staphylococcal endocarditis. Staphylococcal endocarditis represents an increasingly large proportion of patients with infectious endocarditis. Mortality rates remain high despite aggressive management of the patient's condition.


Confinement effects on the mechanical heterogeneity of polymer fiber glasses.
Both polymer fiber glasses and bulk polymer glasses exhibit nonlinear mechanical responses under uniaxial deformation. In polymer fibers, however, polymer chains are confined strongly and the surface area is relatively large compared to their volume. The confinement and the surface may lead to the spatially heterogeneous relaxation of chains in polymer fibers. In this work we perform molecular dynamics simulations and investigate the relation between the heterogeneous dynamics and the nonlinear mechanical responses at a molecular level. Our molecular simulations capture successfully not only the nonlinear mechanical response but also the dependence of mechanical properties on the strain rate of typical polymer glasses as in experiments. We find that the local elastic modulus and the nonaffine displacement are spatially heterogeneous in the pre-yield regime, which results in a lower elastic modulus for polymer fibers than bulk polymer glasses. In the post-yield regime, those mechanical properties become relatively homogeneous. Monomers with large nonaffine displacement are localized mainly at the interfacial region in the pre-yield regime while highly nonaffine monomers are distributed throughout the fibers in the post-yield regime. We show that the nonaffine displacement during deformation relates closely to the mechanical response of the polymer fibers. We also find that in the strain-hardening regime there is a significant difference in the energetic contribution to the stress between polymer fibers and bulk polymers, for which the modulus of the strain-hardening regime of the polymer fibers is smaller than that of bulk polymers.


Mutual fitness benefits arise during coevolution in a nematode-defensive microbe model.
Species interactions can shift along the parasitism-mutualism continuum. However, the consequences of these transitions for coevolutionary interactions remain unclear. We experimentally coevolved a novel species interaction between Caenorhabditis elegans hosts and a mildly parasitic bacterium, Enterococcus faecalis, with host-protective properties against virulent Staphylococcus aureus. Coinfections drove the evolutionary transition of the C. elegans-E. faecalis relationship toward a reciprocally beneficial interaction. As E. faecalis evolved to protect nematodes against S. aureus infection, hosts adapted by accommodating greater numbers of protective bacteria. The mutualism was strongest in pairings of contemporary coevolved populations. To generally assess the conditions under which these defensive mutualisms can arise and coevolve, we analyzed a model that showed that they are favored when mild parasites confer an intermediate level of protection. Our results reveal that coevolution can shape the transition of animal-parasite interactions toward defensive symbioses in response to coinfections.


RNA helicases and abiotic stress.
RNA helicases function as molecular motors that rearrange RNA secondary structure, potentially performing roles in any cellular process involving RNA metabolism. Although RNA helicase association with a range of cellular functions is well documented, their importance in response to abiotic stress is only beginning to emerge. This review summarizes the available data on the expression, biochemistry and physiological function(s) of RNA helicases regulated by abiotic stress. Examples originate primarily from non-mammalian organisms while instances from mammalian sources are restricted to post-translational regulation of helicase biochemical activity. Common emerging themes include the requirement of a cold-induced helicase in non-homeothermic organisms, association and regulation of helicase activity by stress-induced phosphorylation cascades, altered nuclear-cytoplasmic shuttling in eukaryotes, association with the transcriptional apparatus and the diversity of biochemical activities catalyzed by a subgroup of stress-induced helicases. The data are placed in the context of a mechanism for RNA helicase involvement in cellular response to abiotic stress. It is proposed that stress-regulated helicases can catalyze a nonlinear, reversible sequence of RNA secondary structure rearrangements which function in RNA maturation or RNA proofreading, providing a mechanism by which helicase activity alters the activation state of target RNAs through regulation of the reaction equilibrium.


Costs of clinical mastitis and mastitis prevention in dairy herds.
A stratified random sample of 50 Ohio dairy herds, monitored for 1 year between March 1988 and May 1989, was used to estimate the component costs of clinical mastitis per cow-year overall and by organism, the component costs of an episode of clinical mastitis overall and by organism, and the incidence of clinical mastitis by organism. Each herd was visited monthly by a veterinarian who conducted on-farm interviews and completed standardized data-collection forms designed to elicit economic information about the on-farm costs of clinical mastitis and mastitis prevention. Producers collected milk samples prior to treatment of clinical mastitis cases. Culturing methods allowed identification of 18 specific mastitis pathogen classifications. Annual costs estimated were on a per cow-year and clinical episode basis. The monthly mean population of cows monitored was 4,068. Mastitis prevention cost $14.50/cow-year, whereas the cost incurred by producers because of clinical cases of mastitis was $37.91. Organisms prevalent in the cows' environment caused the most costly types of mastitis. Disregarding contaminated samples and episodes for which no milk samples were taken, mastitis for which 2 organisms were isolated accounted for 35.5% of costs of clinical mastitis, followed by cases for which Escherichia coli (21.3%) was isolated, cases for which culturing yielded no growth (8.6%), and cases for which esculin-positive Streptococcus spp (6.4%), Klebsiella spp (5.7%), esculin-negative CAMP-negative Streptococcus spp (5.1%), Enterobacter spp (4.8%), coagulase-negative Staphylococcus spp (4.1%), coagulase-positive Staphylococcus spp (3.0%), S agalactiae (2.5%), and Bacillus spp (1.2%) were isolated.(ABSTRACT TRUNCATED AT 250 WORDS)


Comparison of piperacillin and penicillin in the treatment of uncomplicated gonorrhea.
A total of 120 men with uncomplicated infections caused by beta-lactamase-negative, highly penicillin-susceptible strains of Neisseria gonorrhoeae were included in this study. They were randomly assigned to regimens of either piperacillin (2.0 g) or procaine penicillin G (4.8 X 10(6) U) intramuscularly, both delivered concomitantly with an oral dose of 1.0 g probenecid. A total of 103 patients completed the study, providing data from 112 infected sites: for the penicillin regimen--urethra, 46; pharynx, 5; and rectum, 4; for the piperacillin regimen--urethra, 53; pharynx, 3; and rectum, 1. In the penicillin group, there were no failures at any of the infected sites. In the piperacillin group, all except one pharyngeal infection were cured. Also, in the piperacillin group, four men visit, whereas no cases of this type occurred in the penicillin group. No major side effects were noted in either group. Clinically, piperacillin was as effective as procaine penicillin G in the treatment of gonococcal urethritis in men. Pharyngeal infection may be refractory to piperacillin therapy.


First Report of Alternaria tenuissima Causing Leaf Spot on Eggplant in Malaysia.
A leaf spot on eggplant (Solanum melongena) was observed in major eggplant growing regions in Malaysia, including the Cameron Highlands and Johor State, during 2011. Disease incidence averaged approximately 30% in severely infected regions in about 150 ha of eggplant fields and greenhouses examined. Early symptoms consisted of small, circular, brown, necrotic spots uniformly distributed on leaves. The spots gradually enlarged and developed concentric rings. Eventually, the spots coalesced and caused extensive leaf senescence. A fungus was recovered consistently by plating surface-sterilized (1% NaOCl) sections of symptomatic leaf tissue onto potato dextrose agar (PDA). For conidial production, the fungus was grown on potato carrot agar (PCA) and V8 agar media under a 16-h/8-h dark/light photoperiod at 25°C (4). Fungal colonies were a dark olive color with loose, cottony mycelium. Simple conidiophores were ≤120 μm long and produced numerous conidia in long chains. Conidia averaged 20.0 × 7.5 μm and contained two to five transverse septa and the occasional longitudinal septum. Twelve isolates of the fungus were identified as Alternaria tenuissima on the basis of morphological characterization (4). Confirmation of the species identification was obtained by molecular characterization of the internal transcribed spacer (ITS) region of rDNA amplified from DNA extracted from a representative isolate using universal primers ITS4 and ITS5 (2). The 558 bp DNA band amplified was sent for direct sequencing. The sequence (GenBank Accession No. JQ736021) was subjected to BLAST analysis (1) and was 99% identical to published ITS rDNA sequences of isolates of A. tenuissima (GenBank Accession Nos. DQ323692 and AY154712). Pathogenicity tests were performed by inoculating four detached leaves from 45-day-old plants of the eggplant cv. 125066x with 20 μl drops (three drops/leaf) of a conidial suspension containing 105 conidia/ml in sterile distilled water. Four control leaves were inoculated with sterile water. Leaves inoculated with the fungus and those treated with sterile water were incubated in chambers at 25°C and 95% RH with a 12-h photoperiod/day (2). Leaf spot symptoms typical of those caused by A. tenuissima developed on leaves inoculated with the fungus 7 days after inoculation, and the fungus was consistently reisolated from these leaves. The control leaves remained asymptomatic and the pathogen was not reisolated from the leaves. The pathogenicity test was repeated with similar results. To our knowledge, this is the first report of A. tenuissima causing a leaf spot on eggplant in Malaysia. A. tenuissima has been reported to cause leaf spot and fruit rot on eggplant in India (3). References: (1) S. F. Altschul et al. Nucleic Acids Res. 25:3389, 1997. (2) B. M. Pryor and T. J. Michailides. Phytopathology 92:406, 2002. (3) P. Raja et al. New Disease Rep. 12:31, 2005. (4) E. G. Simmons. Page 1 in: Alternaria Biology, Plant Diseases and Metabolites. J. Chelchowski and A. Visconti, eds. Elsevier, Amsterdam, 1992.


A group independent component analysis of covert verb generation in children: a functional magnetic resonance imaging study.
Semantic language skills are an integral part of early childhood language development. The semantic association between verbs and nouns constitutes an important building block for the construction of sentences. In this large-scale functional magnetic resonance imaging (fMRI) study, involving 336 subjects between the ages of 5 and 18 years, we investigated the neural correlates of covert verb generation in children. Using group independent component analysis (ICA), seven task-related components were identified including the mid-superior temporal gyrus, the most posterior aspect of the superior temporal gyrus, the parahippocampal gyrus, the inferior frontal gyrus, the angular gyrus, and medial aspect of the parietal lobule (precuneus/posterior cingulate). A highly left-lateralized component was found including the medial temporal gyrus, the frontal gyrus, the inferior frontal gyrus, and the angular gyrus. The associated independent component (IC) time courses were analyzed to investigate developmental changes in the neural elements supporting covert verb generation. Observed age effects may either reflect specific local neuroplastic changes in the neural substrates supporting language or a more global transformation of neuroplasticity in the developing brain. The results are analyzed and presented in the framework of two theoretical models for neurocognitive brain development. In this context, group ICA of fMRI data from our large sample of children aged 5-18 years provides strong evidence in support of the regionally weighted model for cognitive neurodevelopment of language networks.


Urinary leakage during exercise: problematic activities, adaptive behaviors, and interest in treatment for physically active Canadian women.
Urine loss during recreational exercise is problematic. We aimed to characterize which activities are most frequently reported as causing leakage for women, adaptive management mechanisms, and awareness and interest in treatment in a cohort of physically active women. We administered an anonymous questionnaire to 59 physically active women in Canada. Surveys were completed electronically or on paper. Demographic information was obtained. Questions about which specific activities caused leakage, adaptive behaviors to deal with urinary loss, and degree of bother were addressed, and knowledge and interest in therapies for leakage were queried. Activities most likely to cause leakage were skipping, trampoline, jumping jacks, and running/jogging. To decrease leakage, 93.2% voided immediately before exercise, 62.7% reported voiding breaks, and some reported fluid restriction (37.3%). Leakage impacted activity level for 50% of women. Most often, activity intensity was decreased (90.3%) or specific activities avoided (80.7%). Pad use during exercise was common (49.2%). Interest in receiving treatment for urinary incontinence (UI) was high (88.1%) despite a large proportion (35.6%) not knowing of available treatments. Interest was highest for pelvic floor physiotherapy (84.6%), although interest in both pessary and surgical management (63.5% each) was significant. Women experiencing UI during exercise report high-impact activities as most frequently causing loss. Adaptive behaviors are common. Physically active women are interested in treatment, and the high interest in pelvic physiotherapy presents a unique opportunity to link pelvic exercise with recreational exercise to meet both cardiovascular and continence needs in the physically active patient population.


A general framework for learning rules from data.
With the aim of getting understandable symbolic rules to explain a given phenomenon, we split the task of learning these rules from sensory data in two phases: a multilayer perceptron maps features into propositional variables and a set of subsequent layers operated by a PAC-like algorithm learns Boolean expressions on these variables. The special features of this procedure are that: i) the neural network is trained to produce a Boolean output having the principal task of discriminating between classes of inputs; ii) the symbolic part is directed to compute rules within a family that is not known a priori; iii) the welding point between the two learning systems is represented by a feedback based on a suitability evaluation of the computed rules. The procedure we propose is based on a computational learning paradigm set up recently in some papers in the fields of theoretical computer science, artificial intelligence and cognitive systems. The present article focuses on information management aspects of the procedure. We deal with the lack of prior information about the rules through learning strategies that affect both the meaning of the variables and the description length of the rules into which they combine. The paper uses the task of learning to formally discriminate among several emotional states as both a working example and a test bench for a comparison with previous symbolic and subsymbolic methods in the field.


Lipids for parenteral nutrition in neonates.
In neonatal intensive care units, the interest and scope for research in the field of intravenous lipids has significantly widened in recent years. This brief review covers the advances in this field in the last 2 years. These include a significant amount of research in evaluating safety and efficacy of novel lipid emulsions that include olive oil or fish oil. Short-term studies involving novel lipid emulsions have documented safety and benefits in terms of reduced inflammation and lipid peroxidation. Fish oil-based lipid emulsions have also been used to prevent and treat parenteral nutrition-induced cholestasis. Other areas of progress include stability studies of all-in-one parenteral nutrition mixtures including lipid emulsions for neonates. Since the first soybean oil-based lipid emulsions were introduced 50 years ago, progress has been made in understanding the composition, dose and clinical effects of parenteral lipids in neonatal patients. However there is a paucity of data in terms of definitive head-to-head trials of different novel lipid emulsions evaluating short-term as well as long-term clinically important outcomes including neurodevelopment. Future research is required to determine long-term benefits of novel lipid emulsions for neurological outcome and effects on the immune system.


Baricitinib in patients with inadequate response or intolerance to conventional synthetic DMARDs: results from the RA-BUILD study.
Baricitinib is an oral, reversible, selective Janus kinase 1 and 2 inhibitor. In this phase III, double-blind 24-week study, 684 biologic disease-modifying antirheumatic drug (DMARD)-naïve patients with rheumatoid arthritis and inadequate response or intolerance to ≥1 conventional synthetic DMARDs were randomly assigned 1:1:1 to placebo or baricitinib (2 or 4 mg) once daily, stratified by region and the presence of joint erosions. Endpoint measures included American College of Rheumatology 20% response (ACR20, primary endpoint), Disease Activity Score (DAS28) and Simplified Disease Activity Index (SDAI) score ≤3.3. More patients achieved ACR20 response at week 12 with baricitinib 4 mg than with placebo (62% vs 39%, p≤0.001). Compared with placebo, statistically significant improvements in DAS28, SDAI remission, Health Assessment Questionnaire-Disability Index, morning joint stiffness, worst joint pain and worst tiredness were observed. In a supportive analysis, radiographic progression of structural joint damage at week 24 was reduced with baricitinib versus placebo. Rates of adverse events during the treatment period and serious adverse events (SAEs), including serious infections, were similar among groups (SAEs: 5% for baricitinib 4 mg and placebo). One patient had an adverse event of tuberculosis (baricitinib 4 mg); one patient had an adverse event of non-melanoma skin cancer (baricitinib 4 mg). Two deaths and three major adverse cardiovascular events occurred (placebo). Baricitinib was associated with a decrease in neutrophils and increases in low-density and high-density lipoprotein. In patients with rheumatoid arthritis and an inadequate response or intolerance to conventional synthetic DMARDs, baricitinib was associated with clinical improvement and inhibition of progression of radiographic joint damage. NCT01721057; Results.


Treatment of bacterial vaginosis: a comparison of oral metronidazole, metronidazole vaginal gel, and clindamycin vaginal cream.
Treatment options for bacterial vaginosis are numerous. The purpose of this study was to compare the efficacy of oral metronidazole, metronidazole vaginal gel, and clindamycin vaginal cream for the treatment of bacterial vaginosis using traditional clinical and laboratory methods, as well as a new DNA probe test. We also determined the percentage of patients receiving each treatment who developed posttreatment vaginal candidiasis, a potential complication of treating bacterial vaginosis. One hundred one women in whom bacterial vaginosis was diagnosed by standard criteria were randomly assigned to receive: oral metronidazole 500 mg twice daily for 1 week, 0.75% metronidazole vaginal gel 5 g twice daily for 5 days, or 2% clindamycin vaginal cream 5 g once daily for 7 days. Women with coexisting vulvovaginal candidiasis or vaginal trichomoniasis were excluded. Tests of cure by vaginal saline wet prep and potassium hydroxide microscopic examinations, Gram's stain, pH and DNA probe tests for Gardnerella vaginalis and Candida species were scheduled 7 to 14 days following treatment. There were no statistically significant differences in cure rates for oral metronidazole (84.2%), metronidazole vaginal gel (75.0%), or clindamycin vaginal cream (86.2%) (chi 2 = 1.204, df = 2, P = .548) using traditional clinical and laboratory criteria. Cure rates were lower based on DNA testing, indicating that Gardnerella vaginalis may remain after a clinical cure. This would explain cases of recurrent disease. Posttreatment vulvovaginal candidiasis was experienced by 12.5% of subjects treated with oral metronidazole, 14.8% of subjects treated with clindamycin vaginal cream, and 30.4% of subjects treated with metronidazole vaginal gel (chi 2 = 2.607, df = 2, P = .272). Oral metronidazole, metronidazole vaginal gel, and clindamycin vaginal cream achieved nearly equivalent cure rates for the treatment of bacterial vaginosis. Patients treated with these agents experienced similar rates of posttreatment vulvovaginal candidiasis, but those using the intravaginal products reported being more satisfied with the treatment.


Transmission of Neospora caninum between wild and domestic animals.
To determine whether deer can transmit Neospora caninum, brains of naturally infected white-tailed deer (Odocoileus virginianus) were fed to 4 dogs; 2 of these dogs shed oocysts. Oocysts from 1 of the dogs were tested by polymerase chain reaction and found to be positive for N. caninum and negative for Hammondia heydorni. The internal transcribed spacer 1 sequence of the new strain (designated NC-deer1) was identical to N. caninum from domestic animals, indicating that N. caninum is transmitted between wild and domestic animals, often enough to prevent divergent evolution of isolated populations of the parasite. NC-deerl oocysts were administered to a calf that developed a high antibody titer, providing evidence that N. caninum from wildlife can infect cattle. In addition, N. caninum antibody seroprevalence was detected in 64/164 (39%) free-ranging gray wolves (Canis lupus), 12/113 (11%) coyotes (Canis latrans), 50/193 (26%) white-tailed deer, and 8/61 (13%) moose (Alces alces). These data are consistent with a sylvatic transmission cycle of N. caninum between cervids and canids. We speculate that hunting by humans favors the transmission of N. caninum from deer to canids, because deer carcasses are usually eviscerated in the field. Infection of canids in turn increases the risk of transmitting the parasite to domestic livestock.


Atmospheric temperature measurements made by rotational Raman scattering.
Rotational Raman scattering of light from the second harmonic of a Nd:YAG laser is used to measure atmospheric temperature at altitudes of 3 to 20 km. The method relies on taking the ratio of light passed by two filters that differ slightly in their passbands, and is therefore insensitive to variations in atmospheric transmission. The calibration of the experiment relies on only spectroscopic measurements and not on normalizing to nearby radiosondes, as has been the previous practice with this kind of experiment. Comparisons with radiosonde profiles show excellent agreement to within the precision of the measurements and the variability of the atmosphere. The main application of the experiment lies in its ability to measure a time series of temperature profiles with good height resolution throughout a night. Examples of such series that show the passage of a tropopause fold above the lidar are presented.


Dopamine release and uptake dynamics within nonhuman primate striatum in vitro.
The putamen of the human striatum is a heterogeneous nucleus that contains the primary site of loss of dopamine (DA) in Parkinson's disease (PD). Furthermore, different functional domains of the putamen are heterogeneously susceptible to DA loss, and yet the dynamic regulation of extracellular DA concentration ([DA](o)) and comparison between domains has not been explored in the primate brain. In these studies, DA was measured in real time using fast-scan cyclic voltammetry at a carbon-fiber microelectrode in vitro in striatal sections from the common marmoset (Callithrix jacchus). [DA](o) released by a single stimulus pulse varied threefold along a ventromedial-dorsolateral axis. DA uptake was via the DA transporter (GBR12909 sensitive, desipramine insensitive). On the basis of data modeling with simulations of Michaelis-Menten kinetics, rate maximum, V(max), varied with region: both [DA](o) and V(max) were greatest in regions most vulnerable in PD. These differences were reflected in part by regional variation in DA content. [DA](o), V(max), and regional variation were two- to threefold greater than in rodent caudatoputamen. In addition, steady-state [DA](o) at physiological firing rates in primate striatum was controlled by depolarization frequency, uptake, and presynaptic autoreceptors. Furthermore, regulation of [DA](o) by these mechanisms differed significantly between limbic- and motor-associated domains. These data indicate interspecies heterogeneity in striatal DA dynamics that must be considered when extrapolating behavioral and drug responses from rodent to the primate brain. Moreover, the heterogeneity demonstrated within the primate putamen in the availability and dynamic regulation of DA may be central to understanding DA function in health, cocaine abuse, and disease.


Outbreaks where food workers have been implicated in the spread of foodborne disease. Part 7. Barriers to reduce contamination of food by workers.
Contamination of food and individuals by food workers has been identified as an important contributing factor during foodborne illness investigations. Physical and chemical barriers to prevent microbial contamination of food are hurdles that block or reduce the transfer of pathogens to the food surface from the hands of a food worker, from other foods, or from the environment. In food service operations, direct contact of food by hands should be prevented by the use of barriers, especially when gloves are not worn. Although these barriers have been used for decades in food processing and food service operations, their effectiveness is sometimes questioned or their use may be ignored. Physical barriers include properly engineered building walls and doors to minimize the flow of outside particles and pests to food storage and food preparation areas; food shields to prevent aerosol contamination of displayed food by customers and workers; work clothing designated strictly for work (clothing worn outdoors can carry undesirable microorganisms, including pathogens from infected family members, into the work environment); and utensils such as spoons, tongs, and deli papers to prevent direct contact between hands and the food being prepared or served. Money and ready-to-eat foods should be handled as two separate operations, preferably by two workers. Chemical barriers include sanitizing solutions used to remove microorganisms (including pathogens) from objects or materials used during food production and preparation and to launder uniforms, work clothes, and soiled linens. However, laundering as normally practiced may not effectively eliminate viral pathogens.


The prevention of mother-to-child transmission of HIV cascade analysis tool: supporting health managers to improve facility-level service delivery.
The objective of the prevention of Mother-to-Child Transmission (pMTCT) cascade analysis tool is to provide frontline health managers at the facility level with the means to rapidly, independently and quantitatively track patient flows through the pMTCT cascade, and readily identify priority areas for clinic-level improvement interventions. Over a period of six months, five experienced maternal-child health managers and researchers iteratively adapted and tested this systems analysis tool for pMTCT services. They prioritized components of the pMTCT cascade for inclusion, disseminated multiple versions to 27 health managers and piloted it in five facilities. Process mapping techniques were used to chart PMTCT cascade steps in these five facilities, to document antenatal care attendance, HIV testing and counseling, provision of prophylactic anti-retrovirals, safe delivery, safe infant feeding, infant follow-up including HIV testing, and family planning, in order to obtain site-specific knowledge of service delivery. Seven pMTCT cascade steps were included in the Excel-based final tool. Prevalence calculations were incorporated as sub-headings under relevant steps. Cells not requiring data inputs were locked, wording was simplified and stepwise drop-offs and maximization functions were included at key steps along the cascade. While the drop off function allows health workers to rapidly assess how many patients were lost at each step, the maximization function details the additional people served if only one step improves to 100% capacity while others stay constant. Our experience suggests that adaptation of a cascade analysis tool for facility-level pMTCT services is feasible and appropriate as a starting point for discussions of where to implement improvement strategies. The resulting tool facilitates the engagement of frontline health workers and managers who fill out, interpret, apply the tool, and then follow up with quality improvement activities. Research on adoption, interpretation, and sustainability of this pMTCT cascade analysis tool by frontline health managers is needed. ClinicalTrials.gov NCT02023658, December 9, 2013.


Family type and accidents in preschool children.
Children living in single-parent families or stepfamilies were found to be more likely to suffer accidental injuries in their first five years of life than children living with two natural parents. Frequent household moves, low maternal age, and perceived poor behaviour in the child were all more strongly associated with overall accident rates than family type, and these disadvantages were more common in atypical families. Family type appeared to be the most important influence on hospital admission after accidents. Overall, there was a close similarity in accident rates between children of single-parent families and stepfamilies, and both groups were more at risk than children living with both natural parents.


Walking to work in Canada: health benefits, socio-economic characteristics and urban-regional variations.
There is mounting concern over increasing rates of physical inactivity and overweight/obesity among children and adult in Canada. There is a clear link between the amount of walking a person does and his or her health. The purpose of this paper is to assess the health factors, socio-economic characteristics and urban-regional variations of walking to work among adults in Canada. Data is drawn from two cycles of the Canadian Community Health Survey: 2001 and 2005. The study population is divided into three groups: non-walkers, lower-duration walkers and high-duration walkers. Logistic regression modeling tests the association between levels of walking and health related outcomes (diabetes, high blood pressure, stress, BMI, physical activity), socio-economic characteristics (sex, age, income, education) and place of residence (selected Census Metropolitan Areas). In 2005, the presence of diabetes and high blood pressure was not associated with any form of walking. Adults within the normal weight range were more likely to be high-duration walkers. Females and younger people were more likely to be lower-duration walkers but less likely to be high-duration walkers. There was a strong association between SES (particularly relative disadvantage) and walking to work. In both 2001 and 2005, the conditions influencing walking to work were especially prevalent in Canada's largest city, Toronto, as well as in several small to medium sized urban areas including Halifax, Kingston, Hamilton, Regina, Calgary and Victoria. A number of strategies can be followed to increase levels of walking in Canada. It is clear that for many people walking to work is not possible. However, strategies can be developed to encourage adults to incorporate walking into their daily work and commuting routines. These include mass transit walking and workplace walking programs.


Niche of harmful alga Aureococcus anophagefferens revealed through ecogenomics.
Harmful algal blooms (HABs) cause significant economic and ecological damage worldwide. Despite considerable efforts, a comprehensive understanding of the factors that promote these blooms has been lacking, because the biochemical pathways that facilitate their dominance relative to other phytoplankton within specific environments have not been identified. Here, biogeochemical measurements showed that the harmful alga Aureococcus anophagefferens outcompeted co-occurring phytoplankton in estuaries with elevated levels of dissolved organic matter and turbidity and low levels of dissolved inorganic nitrogen. We subsequently sequenced the genome of A. anophagefferens and compared its gene complement with those of six competing phytoplankton species identified through metaproteomics. Using an ecogenomic approach, we specifically focused on gene sets that may facilitate dominance within the environmental conditions present during blooms. A. anophagefferens possesses a larger genome (56 Mbp) and has more genes involved in light harvesting, organic carbon and nitrogen use, and encoding selenium- and metal-requiring enzymes than competing phytoplankton. Genes for the synthesis of microbial deterrents likely permit the proliferation of this species, with reduced mortality losses during blooms. Collectively, these findings suggest that anthropogenic activities resulting in elevated levels of turbidity, organic matter, and metals have opened a niche within coastal ecosystems that ideally suits the unique genetic capacity of A. anophagefferens and thus, has facilitated the proliferation of this and potentially other HABs.


Stereoselective esterase activity of human serum albumin toward ketoprofen glucuronide.
Many carboxylic acid-containing drugs undergo conjugation with D-glucuronic acid in humans, leading to the formation of acyl glucuronides, which are excreted into urine. However, these metabolites can be hydrolyzed back to the parent aglycon; this reaction can be accelerated by human serum albumin (HSA). Although this phenomenon of interaction between the acyl glucuronide and HSA has been described for various drugs, the kinetics of the protein have not been characterized. The aim of this study was to investigate the HSA-mediated mechanism involved in the in vitro hydrolysis by albumin of the acyl glucuronides of (R)- and (S)-ketoprofen (a nonsteroidal anti-inflammatory drug), as model compounds. The conjugates of both ketoprofen enantiomers were incubated, separately or together, with increasing concentrations of albumin (14.5-145 microM) at pH 7.4 and 37 degrees. The reaction followed Michaelis-Menten kinetics and was stereoselective; the (R)-ketoprofen glucuronide was a better substrate than the S-conjugate. To identify the HSA domain involved in the hydrolysis reaction, specific probes of HSA binding sites were used as potential inhibitors. These probes, added at an equimolar probe/glucuronide ratio (145 microM), slightly decreased the hydrolysis (by up to 30%). They affected the reversible binding of (R)-ketoprofen glucuronide to HSA, as shown by CD studies. Because iodoacetic acid did not modify the single free cysteine residue on HSA, this amino acid residue cannot be the reactive one. In addition, the chemical modification of a single tyrosine residue (probably Tyr-411) on HSA by diisopropyl fluorophosphate significantly but weakly affected the hydrolysis of (R)-ketoprofen glucuronide, suggesting that this residue also is not involved in the catalysis. In contrast, the R-conjugate was not bound to modified albumin, as revealed in CD experiments. These results support the existence of distinct sites on HSA for reversible binding and hydrolysis of (R)-ketoprofen glucuronide.


A latitudinal gradient in seed nutrients of the forest herb Anemone nemorosa.
The nutrient concentration in seeds determines many aspects of potential success of the sexual reproductive phase of plants, including the seed predation probability, efficiency of seed dispersal and seedling performance. Despite considerable research interest in latitudinal gradients of foliar nutrients, a similar gradient for seeds remains unexplored. We investigated a potential latitudinal gradient in seed nutrient concentrations within the widespread European understorey forest herb Anemone nemorosa L. We sampled seeds of A. nemorosa in 15 populations along a 1900-km long latitudinal gradient at three to seven seed collection dates post-anthesis and investigated the relative effects of growing degree-hours >5 °C, soil characteristics and latitude on seed nutrient concentrations. Seed nitrogen, nitrogen:phosphorus ratio and calcium concentration decreased towards northern latitudes, while carbon:nitrogen ratios increased. When taking differences in growing degree-hours and measured soil characteristics into account and only considering the most mature seeds, the latitudinal decline remained particularly significant for seed nitrogen concentration. We argue that the decline in seed nitrogen concentration can be attributed to northward decreasing seed provisioning due to lower soil nitrogen availability or greater investment in clonal reproduction. This pattern may have large implications for the reproductive performance of this forest herb as the degree of seed provisioning ultimately co-determines seedling survival and reproductive success.


Biological significance of beta hCG, HLA and other membrane antigen expression on bladder tumours and their relationship to tumour infiltrating lymphocytes (TIL).
Expression of beta human chorionic gonadotropin (beta hCG) by bladder tumours has been shown to be associated with increased metastases and resistance to treatment with radiotherapy and chemotherapy. Preliminary results from typing frozen tumours using monoclonal antibodies against HLA determinants show reduced or lost expression of one or more antigens in two thirds of patients studied with a trend for more malignant behaviour and inability to generate tumour infiltrating lymphocyte expression using Interleukin-2 in those patients whose tumours demonstrate loss. In this series beta hCG expression was only seen in a subgroup of those demonstrating loss of HLA antigen expression. Studies of beta hCG secreting bladder cancer cell lines showed that it was possible to induce class II HLA antigen expression with gamma Interferon, and that this treatment but not alpha Interferon reduced beta hCG production by the cell line.


Hippocampal and amygdalar cell-specific translation is similar soon after stress but diverge over time.
Stress is known to cause contrasting patterns of morphological and physiological plasticity in the hippocampus and amygdala. An obligatory cellular process underlying such neural changes is de novo translation and alterations in protein expression. Yet the nature of the translational response to stress in neurons remains largely unexplored. Even less is known about how glia are affected. Using a click-chemistry-based method to label the de novo proteome in live brain slices, we monitored translation in neurons and astrocytes of the basolateral amygdala (BLA) and dorsal hippocampal area CA3 (dCA3) in rats at different time-points after a single 2-hr exposure to immobilization stress. We observed enhancements in neuronal translation in both brain regions 1 hour after stress. This initial increase persisted in the BLA up to 10 days afterwards. In contrast, dCA3 neuronal translation gradually decreased to below control levels 10 days later. Translation profiles of dCA3 astrocytes followed timelines similar to neurons, but in BLA astrocytes translation peaked 1 day later and remained elevated 10 days later. Together our results demonstrate that stress causes an immediate upregulation of protein synthesis in both amygdalar and hippocampal neurons and astrocytes. However, these two areas eventually exhibit opposite temporal profiles of protein expression well after the end of stress. These findings identify new metrics of stress-induced plasticity at the level of cell-type specific proteomic landscape that may provide important insights into the molecular basis of the divergent temporal effects of stress across brain regions and biological scales.


Effects of chromatic image statistics on illumination induced color differences.
We measure the color fidelity of visual scenes that are rendered under different (simulated) illuminants and shown on a calibrated LCD display. Observers make triad illuminant comparisons involving the renderings from two chromatic test illuminants and one achromatic reference illuminant shown simultaneously. Four chromatic test illuminants are used: two along the daylight locus (yellow and blue), and two perpendicular to it (red and green). The observers select the rendering having the best color fidelity, thereby indirectly judging which of the two test illuminants induces the smallest color differences compared to the reference. Both multicolor test scenes and natural scenes are studied. The multicolor scenes are synthesized and represent ellipsoidal distributions in CIELAB chromaticity space having the same mean chromaticity but different chromatic orientations. We show that, for those distributions, color fidelity is best when the vector of the illuminant change (pointing from neutral to chromatic) is parallel to the major axis of the scene's chromatic distribution. For our selection of natural scenes, which generally have much broader chromatic distributions, we measure a higher color fidelity for the yellow and blue illuminants than for red and green. Scrambled versions of the natural images are also studied to exclude possible semantic effects. We quantitatively predict the average observer response (i.e., the illuminant probability) with four types of models, differing in the extent to which they incorporate information processing by the visual system. Results show different levels of performance for the models, and different levels for the multicolor scenes and the natural scenes. Overall, models based on the scene averaged color difference have the best performance. We discuss how color constancy algorithms may be improved by exploiting knowledge of the chromatic distribution of the visual scene.


Young and Middle-Aged Schoolteachers Differ in the Neural Correlates of Memory Encoding and Cognitive Fatigue: A Functional MRI Study.
This investigation was inspired by growing evidence that middle-aged persons in a cognitively demanding profession might be characterized by subtle cognitive fatigue. We studied young and middle-aged male schoolteachers. They were compared in a study with functional magnetic resonance imaging to evaluate differences during successful memory encoding. The schoolteachers were additionally subjected to an induced fatigue condition involving the sustained performance of cognitively demanding tasks and to a control condition. Results showed age-related brain activation differences underlying behavioral performance including: (1) greater activation in middle-aged vs. young teachers in bilateral prefrontal cortex (PFC) areas; and (2) differential fatigue effects in the left anterior cingulate cortex (ACC) depending on age group. Middle-aged schoolteachers showed decreased ACC activation in the fatigue compared to the control condition, whereas no change in activation was found in young teachers. Findings demonstrate age effects in these middle-aged subjects that are typically found in older adults, specifically in PFC over-activation. Findings also indicate that already in middle age cognitive aging may be associated with greater resource depletion following sustained task performance. The findings underscore the notion that persons in a cognitively demanding profession can experience subtle age effects, which are evident on fMRI and which impact daily functioning. Possible practical implications for middle-aged schoolteachers are discussed.


Structure-guided development of affinity probes for tyrosine kinases using chemical genetics.
As key components in nearly every signal transduction pathway, protein kinases are attractive targets for the regulation of cellular signaling by small-molecule inhibitors. We report the structure-guided development of 6-acrylamido-4-anilinoquinazoline irreversible kinase inhibitors that potently and selectively target rationally designed kinases bearing two selectivity elements that are not found together in any wild-type kinase: an electrophile-targeted cysteine residue and a glycine gatekeeper residue. Cocrystal structures of two irreversible quinazoline inhibitors bound to either epidermal growth factor receptor (EGFR) or engineered c-Src show covalent inhibitor binding to the targeted cysteine (Cys797 in EGFR and Cys345 in engineered c-Src). To accommodate the new covalent bond, the quinazoline core adopts positions that are different from those seen in kinase structures with reversible quinazoline inhibitors. Based on these structures, we developed a fluorescent 6-acrylamido-4-anilinoquinazoline affinity probe to report the fraction of kinase necessary for cellular signaling, and we used these reagents to quantitate the relationship between EGFR stimulation by EGF and its downstream outputs-Akt, Erk1 and Erk2.


Synthesis, structures, and dearomatization by deprotonation of iron complexes featuring bipyridine-based PNN pincer ligands.
The synthesis and characterization of new iron pincer complexes bearing bipyridine-based PNN ligands is reported. Three phosphine-substituted pincer ligands, namely, the known (t)Bu-PNN (6-((di-tert-butylphosphino)methyl)-2,2'-bipyridine) and the two new (i)Pr-PNN (6-((di-iso-propylphosphino)methyl)-2,2'-bipyridine) and Ph-PNN (6-((diphenylphosphino)methyl)-2,2'-bipyridine) ligands were synthesized and studied in ligation reactions with iron(II) chloride and bromide. These reactions lead to the formation of two types of complexes: mono-chelated neutral complexes of the type [(R-PNN)Fe(X)2] and bis-chelated dicationic complexes of the type [(R-PNN)2Fe](2+). The complexes [(R-PNN)Fe(X)2] (1: R = (t)Bu, X = Cl, 2: R = (t)Bu, X = Br, 3: R = (i)Pr, X = Cl, and 4: R = (i)Pr, X = Br) are readily prepared from reactions of FeX2 with the free R-PNN ligand in a 1:1 ratio. Magnetic susceptibility measurements show that these complexes have a high-spin ground state (S = 2) at room temperature. Employing a 2-fold or higher excess of (i)Pr-PNN, diamagnetic hexacoordinated dicationic complexes of the type [((i)Pr-PNN)2Fe](X)2 (5: X = Cl, and 6: X = Br) are formed. The reactions of Ph-PNN with FeX2 in a 1:1 ratio lead to similar complexes of the type [(Ph-PNN)2Fe](FeX4) (7: X = Cl, and 8: X = Br). Single crystal X-ray studies of 1, 2, 4, 6, and 8 do not indicate electron transfer from the Fe(II) centers to the neutral bipyridine unit based on the determined bond lengths. Density functional theory (DFT) calculations were performed to compare the relative energies of the mono- and bis-chelated complexes. The doubly deprotonated complexes [(R-PNN*)2Fe] (9: R = (i)Pr, and 10: R = Ph) were synthesized by reactions of the dicationic complexes 6 and 8 with KO(t)Bu. The dearomatized nature of the central pyridine of the pincer ligand was established by X-ray diffraction analysis of single crystals of 10. Reactivity studies show that 9 and 10 have a slightly different behavior in protonation reactions.


Torsade de pointes as a reperfusion arrhythmia following intravenous thrombolytic therapy.
Many types of cardiac arrhythmias have been noted following acute myocardial infarction. Polymorphic ventricular arrhythmias (polymorphic ventricular tachycardia and ventricular fibrillation) related to an acute myocardial infarction generally strike during the hyperacute phase, are clearly related to ischaemia and are not associated with a long QT interval time. Pause-dependent Torsade de pointes has been reported following acute myocardial infarction and this arrhythmia generally occurs 3-11 days after the onset of acute myocardial infarction and none has been reported during the hyperacute phase. Torsade de pointes - a specific ventricular tachycardia with specific characteristics has been described in hypokalemia, hypomagnesaemia, during Quinidine therapy, and while using phenothiazines and tricyclic antidepressants. It is reported following liquid protein diet, brady-arrhythmias [especially III° AV Block], sick-sinus syndromes. Torsade de pointes either pause-dependent or pause-independent occurring directly as a reperfusion arrhythmia during intravenous thrombolytic therapy has not been reported in the literature to the best of the authors knowledge. Here, an episode of Torsade de pointes as a direct consequence of reperfusion following thrombolytic therapy in a patient of acute myocardial infarction is described.


Leptin Receptor Expression in Mouse Intracranial Perivascular Cells.
Past studies have suggested that non-neuronal brain cells express the leptin receptor. However, the identity and distribution of these leptin receptor-expressing non-neuronal brain cells remain debated. This study assessed the distribution of the long form of the leptin receptor (LepRb) in non-neuronal brain cells using a reporter mouse model in which LepRb-expressing cells are permanently marked by tdTomato fluorescent protein (LepRb-CretdTomato). Double immunohistochemistry revealed that, in agreement with the literature, the vast majority of tdTomato-tagged cells across the mouse brain were neurons (i.e., based on immunoreactivity for NeuN). Non-neuronal structures also contained tdTomato-positive cells, including the choroid plexus and the perivascular space of the meninges and, to a lesser extent, the brain. Based on morphological criteria and immunohistochemistry, perivascular cells were deduced to be mainly pericytes. Notably, tdTomato-positive cells were immunoreactive for vitronectin and platelet derived growth factor receptor beta (PDGFBR). In situ hybridization studies confirmed that most tdTomato-tagged perivascular cells were enriched in leptin receptor mRNA (all isoforms). Using qPCR studies, we confirmed that the mouse meninges were enriched in Leprb and, to a greater extent, the short isoforms of the leptin receptor. Interestingly, qPCR studies further demonstrated significantly altered expression for Vtn and Pdgfrb in the meninges and hypothalamus of LepRb-deficient mice. Collectively, our data demonstrate that the only intracranial non-neuronal cells that express LepRb in the adult mouse are cells that form the blood-brain barrier, including, most notably, meningeal perivascular cells. Our data suggest that pericytic leptin signaling plays a role in the integrity of the intracranial perivascular space and, consequently, may provide a link between obesity and numerous brain diseases.


Computational prediction of residues involved in fidelity checking for DNA synthesis in DNA polymerase I.
Recent single-molecule Förster resonance energy transfer studies of DNA polymerase I have led to the proposal of a postinsertion fidelity-checking site. This site is hypothesized to ensure proper base pairing of the newly inserted nucleotide. To help test this hypothesis, we have used energy decomposition, electrostatic free energy response, and noncovalent interaction analysis analyses to identify residues involved in this putative checking site. We have used structures of DNA polymerase I from two different organisms, the Klenow fragment from Escherichia coli and the Bacillus fragment from Bacillus stearothermophilus. Our results point to several residues that show altered interactions for three mispairs compared to the correctly paired DNA dimer. Furthermore, many of these residues are conserved among A family polymerases. The identified residues provide potential targets for mutagenesis studies for investigation of the fidelity-checking site hypothesis.


Natural selection in utero induced by mass layoffs: the hCG evidence.
Evolutionary theory, when coupled with research from epidemiology, demography, and population endocrinology, suggests that contracting economies affect the fitness and health of human populations via natural selection in utero. We know, for example, that fetal death increases more among males than females when the economy unexpectedly contracts; that unexpected economic contraction predicts low secondary sex ratios; and that males from low sex ratio birth cohorts live, on average, longer than those from high sex ratio cohorts. We also know that low levels of human chorionic gonadotropin (i.e., hCG) measured in the serum of pregnant women predict fetal death. We do not, however, know whether male survivors of conception cohorts subjected to contracting economies exhibit, as theory predicts, higher hCG than those from other cohorts. We show, in 71 monthly conception cohorts including nearly two million California births, that they do. We thereby add to the literature suggesting that the economy, a phenomenon over which we collectively exercise at least some control, affects population health. Our findings imply that the effect arises via natural selection - a mechanism we largely ignore when attempting to explain, or alter, how collective choice affects our biology.


Oxidative damage and cellular defense mechanisms in sea urchin models of aging.
The free radical, or oxidative stress, theory of aging proposes that the accumulation of oxidative cellular damage is a major contributor to the aging process and a key determinant of species longevity. This study investigates the oxidative stress theory in a novel model for aging research, the sea urchin. Sea urchins present a unique model for the study of aging because of the existence of species with tremendously different natural life spans, including some species with extraordinary longevity and negligible senescence. Cellular oxidative damage, antioxidant capacity, and proteasome enzyme activities were measured in the tissues of three sea urchin species: short-lived Lytechinus variegatus, long-lived Strongylocentrotus franciscanus, and Strongylocentrotus purpuratus, which has an intermediate life span. Levels of protein carbonyls and 4-hydroxynonenal measured in tissues (muscle, nerve, esophagus, gonad, coelomocytes, ampullae) and 8-hydroxy-2'-deoxyguanosine measured in cell-free coelomic fluid showed no general increase with age. The fluorescent age pigment lipofuscin, measured in muscle, nerve, and esophagus, increased with age; however, it appeared to be predominantly extracellular. Antioxidant mechanisms (total antioxidant capacity, superoxide dismutase) and proteasome enzyme activities were maintained with age. In some instances, levels of oxidative damage were lower and antioxidant activity higher in cells or tissues of the long-lived species compared to the short-lived species; however, further studies are required to determine the relationship between oxidative damage and longevity in these animals. Consistent with the predictions of the oxidative stress theory of aging, the results suggest that negligible senescence is accompanied by a lack of accumulation of cellular oxidative damage with age, and maintenance of antioxidant capacity and proteasome enzyme activities may be important mechanisms to mitigate damage.


A technique for the measurement of orthophosphate in human erythrocytes, and some studies of its determinants.
A technique is described for the determination of orthophosphate (Pi) in human erythrocytes. The advantages of the technique are that it uses whole blood rather than separated erythrocytes, that it avoids major hydrolysis of organic phosphates, that it takes account of incomplete recovery of Pi and that it minimizes the effects of chilling the cells. In chilled samples from 46 patients in an intensive care unit, the cellular concentration of Pi was proportional to that in plasma. Blood samples from nine normal subjects were incubated at 37 degrees C. The cellular Pi was 0.79 mmol/litre of cells using an external standardization and 0.67 using an internal standardization. When the same cell samples were chilled on ice for 30 min, the internally standardized value decreased further to 0.57 mmol/litre of cells. These results suggest that differences in recovery, and the extent of chilling, contribute to the variability in the previously reported values for erythrocyte Pi. If Pi, like chloride, had distributed passively between cells and plasma in these samples, the cell to plasma molar concentration ratio for Pi should have been 0.29, compared with the measured value of 0.64. This difference suggests that some factor, in addition to passive diffusion, determined the distribution of Pi.


Influence of Baseline Characteristics, Operative Conduct, and Postoperative Course on 30-Day Outcomes of Coronary Artery Bypass Grafting Among Patients With Left Ventricular Dysfunction: Results From the Surgical Treatment for Ischemic Heart Failure (STICH) Trial.
Patients with severe left ventricular dysfunction, ischemic heart failure, and coronary artery disease suitable for coronary artery bypass grafting (CABG) are at higher risk for surgical morbidity and mortality. Paradoxically, those patients with the most severe coronary artery disease and ventricular dysfunction who derive the greatest clinical benefit from CABG are also at the greatest operative risk, which makes decision making regarding whether to proceed to surgery difficult in such patients. To better inform such decision making, we analyzed the Surgical Treatment for Ischemic Heart Failure (STICH) CABG population for detailed information on perioperative risk and outcomes. In both STICH trials (hypotheses), 2136 patients with a left ventricular ejection fraction of ≤35% and coronary artery disease were allocated to medical therapy, CABG plus medical therapy, or CABG with surgical ventricular reconstruction. Relationships of baseline characteristics and operative conduct with morbidity and mortality at 30 days were evaluated. There were a total of 1460 patients randomized to and receiving surgery, and 346 (≈25%) of these high-risk patients developed a severe complication within 30 days. Worsening renal insufficiency, cardiac arrest with cardiopulmonary resuscitation, and ventricular arrhythmias were the most frequent complications and those most commonly associated with death. Mortality at 30 days was 5.1% and was generally preceded by a serious complication (65 of 74 deaths). Left ventricular size, renal dysfunction, advanced age, and atrial fibrillation/flutter were significant preoperative predictors of mortality within 30 days. Cardiopulmonary bypass time was the only independent surgical variable predictive of 30-day mortality. CABG can be performed with relatively low 30-day mortality in patients with left ventricular dysfunction. Serious postoperative complications occurred in nearly 1 in 4 patients and were associated with mortality. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00023595.


Risk of type 2 diabetes and cardiovascular disease in an incident cohort of people with psoriatic arthritis: a population-based cohort study.
To determine the risk of type 2 diabetes (T2D) and cardiovascular diseases in PsA patients compared with the general population and patients with psoriasis. Incident PsA patients aged 18-89 years were identified in the UK Clinical Practice Research Datalink between 1998 and 2014 and were matched (1:4 ratio) to a general population cohort and psoriasis cohort. The incidence of T2D, cerebrovascular disease, ischaemic heart disease and peripheral vascular disease (PVD) was calculated for each study cohort. Conditional Poisson regression was used to calculate adjusted relative risks. We identified 6783 incident cases of PsA. The risk of T2D was significantly higher in the PsA cohort than in the general population and the psoriasis cohorts [adjusted relative risk 1.40 (CI95 1.15, 1.70) and adjusted relative risk 1.53 (CI95 1.19, 1.97), respectively]. The incidence of ischaemic heart disease, peripheral vascular disease and the three cardiovascular outcomes combined in the PsA cohort was significantly higher than in the general population. No significant differences in risk were observed between the PsA and psoriasis cohorts for any cardiovascular outcome. The development of T2D in an incident population of PsA is significantly higher than in psoriasis alone or in a general population, whereas the increased risk of cardiovascular disease in PsA and psoriasis is similar.


Communicative development in Swedish children 16-28 months old: the Swedish early communicative development inventory--words and sentences.
To describe the development of words and sentences in Swedish children 16-28 months old, 900 parental reports on 336 children were analyzed. Subjects were randomly selected from the national birth register, and there was a response rate of 88%. The assessments were made using the Swedish Early Communicative Development Inventory--words and sentences (SECDI--w&s). Age-based norms for productive vocabulary, pragmatic skills, grammar skills, and maximum length of utterance (MaxLU) were determined. We describe the development of feedback morphemes, semantic categories, and single words and tasks. Correlation across measures was significant, and especially strong between vocabulary size and grammar skills. Optimized positive predictive values were high for 25 to 28 month predictions (71%-88%), and vocabulary scores were found to be of particular predictive importance. No significant gender differences were detected. The clinical relevance of the instrument is discussed.


β-sitosterol in different parts of Saraca asoca and herbal drug ashokarista: Quali-quantitative analysis by liquid chromatography-mass spectrometry.
β-sitosterol is an important component in food and herbal products and beneficial in hyperlipidemia. Its higher concentrations in serum may lead to coronary artery disease in case of sitosterolemia. Therefore, it is essential to determine the quantity of β-sitosterol in food and herbal drugs. Saraca asoca and its preparations have been widely used by traditional healers are also a source of β-sitosterol. In the present study, quantitative estimation of β-sitosterol present in hot and cold water extracts of bark, regenerated bark, leaves and flowers of the S. asoca and Ashokarista drugs were carried out first time using high performance liquid chromatography coupled (HPLC) with quadrupole time-of-flight mass spectrometry. Different concentrations of β-sitosterol and crude extracts were estimated by HPLC and targeted mass spectrometry. Standard curve for β-sitosterol was prepared from the intensities of transitions (397.50 → 147.0987 m/z) having regression coefficient (r (2)) 0.9952. Out of eight extracts and two drugs used in the study bark water, leaves water and leaves hot water extracts were found to have a considerable quantity of β-sitosterol, i.e. 170, 123.5 and 19.3 ng/mL, respectively. The results showed significant differences in the distribution of β-sitosterol among different organs of S. asoca and drugs prepared from its bark. HPLC/electrospray ionizationmass spectroscopy method is accurate, reproducible and requires less specimen, sample preparation and analysis time over HPLC assay. This type of approaches could be helpful for the quality control of herbal medicines and provides necessary information for the rational utilization of plant resources.


A replaceable liposomal aptamer for the ultrasensitive and rapid detection of biotin.
Biotin is an essential vitamin which plays an important role for maintaining normal physiological function. A rapid, sensitive, and simple method is necessary to monitor the biotin level. Here, we reported a replacement assay for the detection of biotin using a replaceable liposomal aptamer. Replacement assay is a competitive assay where a sample analyte replaces the labeled competitor of analyte out of its biorecognition element on a surface. It is user friendly and time-saving because of washing free. We used aptamer as a competitor, not a biorecognition element as tradition. To label aptamers, we used cholesterol-conjugated aptamers to tag signal-amplifying-liposomes. Without the need of conjugation procedure, aptamers can be easily incorporated into the surface of dye-encapsulating liposomes. Two aptamers as competitors of biotin, ST-21 and ST-21M with different affinities to streptavidin, were studied in parallel for the detection of biotin using replacement assays. ST-21 and ST-21M aptamers reached to limits of detection of 1.32 pg/80 μl and 0.47 pg/80 μl, respectively. The dynamic ranges of our assays using ST-21 and ST-21M aptamers were seven and four orders of magnitude, respectively. This assay can be completed in 20 minutes without washing steps. These results were overall better than previous reported assays.


Uncertainty in integrative structural modeling.
Integrative structural modeling uses multiple types of input information and proceeds in four stages: (i) gathering information, (ii) designing model representation and converting information into a scoring function, (iii) sampling good-scoring models, and (iv) analyzing models and information. In the first stage, uncertainty originates from data that are sparse, noisy, ambiguous, or derived from heterogeneous samples. In the second stage, uncertainty can originate from a representation that is too coarse for the available information or a scoring function that does not accurately capture the information. In the third stage, the major source of uncertainty is insufficient sampling. In the fourth stage, clustering, cross-validation, and other methods are used to estimate the precision and accuracy of the models and information.


Studies on cell division in mammalian cells. VII. A temperature-sensitive cell line abnormal in centriole separation and chromosome movement.
A temperature-sensitive Syrian hamster mutant cell line, ts-745, exhibiting novel mitotic events has been isolated. The cells show normal growth and mitosis at 33 degrees C, the permissive temperature. At the nonpermissive temperature of 39 degrees C, mitotic progression becomes aberrant. Metaphase cells and those cells still able to form a metaphase configuration continue through and complete normal cell division. However, cells exposed to 39 degrees C for longer than 15 min can not form a normal metaphase spindle. Instead, the chromosomes are distributed in a spherical shell, with microtubules (MT) radiating to the chromosomes from four closely associated centrioles near the center of the cell. The cells progress from the spherical monopolar state to other monopolar orientations conical in appearance with four centrioles in the apex region. Organized chromosome movement is present, from the spherical shell state to the asymmetrical orientations. Chromosomes remain in the metaphase configuration without chromatid separation. Prometaphase chromosome congression appears normal, as the chromosomes and MT form a stable monopolar spindle, but bipolar spindle formation is apparently blocked in a premetaphase state. When returned from 39 degrees to 33 degrees C, the defective phenotype is readily reversible. At 39 degrees C, the mitotic abnormality lasts 3-5 h, followed by reformation of a single nucleus and cell flattening in an interphase-like state. Subsequent cell cycle events appear to occur, as the cells duplicate chromosomes and initiate a second round of abnormal mitosis. Cell cycle traversion continues for at least 5 d in some cells despite abnormal mitosis resulting in cells accumulating several hundred chromosomes.


Altered corpus callosum morphology associated with autism over the first 2 years of life.
Numerous brain imaging studies indicate that the corpus callosum is smaller in older children and adults with autism spectrum disorder. However, there are no published studies examining the morphological development of this connective pathway in infants at-risk for the disorder. Magnetic resonance imaging data were collected from 270 infants at high familial risk for autism spectrum disorder and 108 low-risk controls at 6, 12 and 24 months of age, with 83% of infants contributing two or more data points. Fifty-seven children met criteria for ASD based on clinical-best estimate diagnosis at age 2 years. Corpora callosa were measured for area, length and thickness by automated segmentation. We found significantly increased corpus callosum area and thickness in children with autism spectrum disorder starting at 6 months of age. These differences were particularly robust in the anterior corpus callosum at the 6 and 12 month time points. Regression analysis indicated that radial diffusivity in this region, measured by diffusion tensor imaging, inversely predicted thickness. Measures of area and thickness in the first year of life were correlated with repetitive behaviours at age 2 years. In contrast to work from older children and adults, our findings suggest that the corpus callosum may be larger in infants who go on to develop autism spectrum disorder. This result was apparent with or without adjustment for total brain volume. Although we did not see a significant interaction between group and age, cross-sectional data indicated that area and thickness differences diminish by age 2 years. Regression data incorporating diffusion tensor imaging suggest that microstructural properties of callosal white matter, which includes myelination and axon composition, may explain group differences in morphology.


Deficiency in metabolic regulators PPARγ and PTEN cooperates to drive keratinizing squamous metaplasia in novel models of human tissue regeneration.
Hindgut-derived endoderm can differentiate into rectal, prostatic, and bladder phenotypes. Stromal-epithelial interactions are crucial for this development; however, the precise mechanisms by which epithelium responds to stromal cues remain unknown. We have previously reported ectopic expression of peroxisome proliferator-activated receptor-γ2 (PPARγ2) increased androgen receptor expression and promoted differentiation of mouse prostate epithelium. PPARγ is also implicated in urothelial differentiation. Herein we demonstrate that knockdown of PPARγ2 in benign human prostate epithelial cells (BHPrEs) promotes urothelial transdifferentiation. Furthermore, in vitro and in vivo heterotypic tissue regeneration models with embryonic bladder mesenchyme promoted urothelial differentiation of PPARγ2-deficient BHPrE cells, and deficiency of both PPARγ isoforms 1 and 2 arrested differentiation. Because PTEN deficiency is cooperative in urothelial pathogenesis, we engineered BHPrE cells with combined knockdown of PPARγ and PTEN and performed heterotypic recombination experiments using embryonic bladder mesenchyme. Whereas PTEN deficiency alone induced latent squamous differentiation in BHPrE cells, combined PPARγ and PTEN deficiency accelerated the development of keratinizing squamous metaplasia (KSM). We further confirmed via immunohistochemistry that gene expression changes in metaplastic recombinants reflected human urothelium undergoing KSM. In summary, these data suggest that PPARγ isoform expression provides a molecular basis for observations that adult human epithelium can be transdifferentiated on the basis of heterotypic mesenchymal induction. These data also implicate PPARγ and PTEN inactivation in the development of KSM.


Review article: fructose malabsorption and the bigger picture.
Fructose is found widely in the diet as a free hexose, as the disaccharide, sucrose and in a polymerized form (fructans). Free fructose has limited absorption in the small intestine, with up to one half of the population unable to completely absorb a load of 25 g. Average daily intake of fructose varies from 11 to 54 g around the world. Fructans are not hydrolysed or absorbed in the small intestine. The physiological consequences of their malabsorption include increasing osmotic load, providing substrate for rapid bacterial fermentation, changing gastrointestinal motility, promoting mucosal biofilm and altering the profile of bacteria. These effects are additive with other short-chain poorly absorbed carbohydrates such as sorbitol. The clinical significance of these events depends upon the response of the bowel to such changes; they have a higher chance of inducing symptoms in patients with functional gut disorders than asymptomatic subjects. Restricting dietary intake of free fructose and/or fructans may have durable symptomatic benefits in a high proportion of patients with functional gut disorders, but high quality evidence is lacking. It is proposed that confusion over the clinical relevance of fructose malabsorption may be reduced by regarding it not as an abnormality but as a physiological process offering an opportunity to improve functional gastrointestinal symptoms by dietary change.


A link between high serum levels of human chorionic gonadotrophin and chorionic expression of its mature functional receptor (LHCGR) in Down's syndrome pregnancies.
Human chorionic gonadotrophin (hCG) is released from placental trophoblasts and is involved in establishing pregnancy by maintaining progesterone secretion from the corpus luteum. Serum hCG is detected in the maternal circulation within the first 2-3 wks of gestation and peaks at the end of the first trimester before declining. In Down's syndrome (DS) pregnancies, serum hCG remains significantly high compared to gestation age-matched uncompromised pregnancies. It has been proposed that increased serum hCG levels could be due to transcriptional hyper-activation of the CGB (hCG beta) gene, or an increased half life of glycosylated hCG hormone, or both. Another possibility is that serum hCG levels remain high due to reduced availability of the hormone's cognate receptor, LHCGR, leading to lack of hormone utilization. We have tested this hypothesis by quantifying the expression of the hCG beta (CGB) RNA, LHCGR RNA and LHCGR proteins in chorionic villous samples. We demonstrate that chorionic expression of hCG beta (CGB) mRNA directly correlates with high serum hCG levels. The steady-state synthesis of LHCGR mRNA (exons 1-5) in DS pregnancies was significantly higher than that of controls, but the expression of full-length LHCGR mRNA (exons 1-11) in DS was comparable to that of uncompromised pregnancies. However, the synthesis of high molecular weight mature LHCGR proteins was significantly reduced in DS compared to uncompromised pregnancies, suggesting a lack of utilization of circulating hCG in DS pregnancies.


Genetic Diversity and Aggressiveness of Ralstonia solanacearum Strains Causing Bacterial Wilt of Potato in Uruguay.
Bacterial wilt, caused by Ralstonia solanacearum, is a major disease affecting potato (Solanum tuberosum) production worldwide. Although local reports suggest that the disease is widespread in Uruguay, characterization of prevalent R. solanacearum strains in that country has not been done. In all, 28 strains of R. solanacearum isolated from major potato-growing areas in Uruguay were evaluated, including 26 strains isolated from potato tubers and 2 from soil samples. All strains belonged to phylotype IIB, sequevar 1 (race 3, biovar 2). Genetic diversity of strains was assessed by repetitive-sequence polymerase chain reaction, which showed that the Uruguayan strains constituted a homogeneous group. In contrast, inoculation of the strains on tomato and potato plants showed, for the first time, different levels of aggressiveness among R. solanacearum strains belonging to phylotype IIB, sequevar 1. Aggressiveness assays were also performed on accessions of S. commersonii, a wild species native to Uruguay that is a source of resistance for potato breeding. No significant interactions were found between bacterial strains and potato and S. commersonii genotypes, and differences in aggressiveness among R. solanacearum strains were consistent with previously identified groups based on tomato and potato inoculations. Moreover, variation in responses to R. solanacearum was observed among the S. commersonii accessions tested.


Oleic acid induces migration through a FFAR1/4, EGFR and AKT-dependent pathway in breast cancer cells.
Free fatty acids (FFAs) are an energy source, and induce activation of signal transduction pathways that mediate several biological processes. In breast cancer cells, oleic acid (OA) induces proliferation, matrix metalloproteinase-9 (MMP-9) secretion, migration and invasion. However, the signal transduction pathways that mediate migration and invasion induced by OA in breast cancer cells have not been studied in detail. We demonstrate here that FFAR1 and FFAR4 mediate migration induced by OA in MDA-MB-231 and MCF-7 breast cancer cells. Moreover, OA induces migration, invasion, AKT1 and AKT2 activation, 12-LOX secretion and an increase of NFκB-DNA binding activity in breast cancer cells. Cell migration requires FFAR1, FFAR4, EGFR, AKT and PI3K activity, whereas invasion is mediated though a PI3K/Akt-dependent pathway. Furthermore, OA promotes relocalization of paxillin to focal contacts and it requires PI3K and EGFR activity, whereas NFκB-DNA binding activity requires PI3K and AKT activity.