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Obesity is a major public health problem affecting overall physical and emotional well-being. Despite compelling data suggesting an association between obesity and cognitive dysfunction, this phenomenon has received relatively little attention. Neuroimaging studies in obese humans report reduced size of brain regions involved in cognition, but few studies have investigated the cellular processes underlying cognitive decline in obesity or the influence of obesity on cognition in the absence of obesity-related illnesses. Here, a rat model of diet-induced obesity was used to explore changes in brain regions important for cognition. Obese rats showed deficits on cognitive tasks requiring the prefrontal and perirhinal cortex. Cognitive deficits were accompanied by decreased dendritic spine density and synaptic marker expression in both brain regions. Microglial morphology was also changed in the prefrontal cortex. Detrimental changes in the prefrontal cortex and perirhinal cortex occurred before metabolic syndrome or diabetes, suggesting that these brain regions may be particularly vulnerable to early stage obesity.

While most animals thermotax only to regulate their temperature, female mosquitoes are attracted to human body heat during pursuit of a blood meal. Here we elucidate the basic rules of Aedes aegypti thermotaxis and test the function of candidate thermoreceptors in this important behavior. We show that host-seeking mosquitoes are maximally attracted to thermal stimuli approximating host body temperatures, seeking relative warmth while avoiding both relative cool and stimuli exceeding host body temperature. We found that the cation channel TRPA1, in addition to playing a conserved role in thermoregulation and chemosensation, is required for this specialized host-selective thermotaxis in mosquitoes. During host-seeking, AaegTRPA1(-/-) mutants failed to avoid stimuli exceeding host temperature, and were unable to discriminate between host-temperature and high-temperature stimuli. TRPA1-dependent tuning of thermotaxis is likely critical for mosquitoes host-seeking in a complex thermal environment in which humans are warmer than ambient air, but cooler than surrounding sun-warmed surfaces.

Phosphoinositide 3-kinases (PI3Ks) are a family of lipid kinases that are activated by growth factor and G-protein-coupled receptors and propagate intracellular signals for growth, survival, proliferation, and metabolism. p85 alpha, a modular protein consisting of five domains, binds and inhibits the enzymatic activity of class IA PI3K catalytic subunits. Here, we describe the structural states of the p85 alpha dimer, based on data from in vivo and in vitro solution characterization. Our in vitro assembly and structural analyses have been enabled by the creation of cysteine-free p85 alpha that is functionally equivalent to native p85 alpha. Analytical ultracentrifugation studies showed that p85 alpha undergoes rapidly reversible monomer-dimer assembly that is highly exothermic in nature. In addition to the documented SH3-PR1 dimerization interaction, we identified a second intermolecular interaction mediated by cSH2 domains at the C-terminal end of the polypeptide. We have demonstrated in vivo concentration-dependent dimerization of p85 alpha using fluorescence fluctuation spectroscopy. Finally, we have defined solution conditions under which the protein is predominantly monomeric or dimeric, providing the basis for small angle x-ray scattering and chemical cross-linking structural analysis of the discrete dimer. These experimental data have been used for the integrative structure determination of the p85 alpha dimer. Our study provides new insight into the structure and assembly of the p85 alpha homodimer and suggests that this protein is a highly dynamic molecule whose conformational flexibility allows it to transiently associate with multiple binding proteins.

Objective: To determine live-birth rates (LBRs) at various ages in very poor prognosis patients, who are defined as poor responders under the Bologna criteria. Design: Retrospective cohort study. Setting: Academically affiliated private fertility center. Patient(s): Among 483 patients, who under the Bologna criteria (three or fewer oocytes, >40 years of age, and/or antimullerian hormone [AMH] <1.1 ng/mL [2/3 criteria minimum]) were poor responders, 278 (381 fresh IVF cycles) qualified for the study because they had at least one embryo on day 3 for transfer. Intervention(s): IVF cycles in women with low functional ovarian reserve, involving androgen and CoQ10 supplementation and ovarian stimulation with daily gonadotropin dosages of 300-450 IU of FSH and 150 IU of hMG in microdose agonist cycles. Main Outcome Measure(s): Age-specific LBRs per ET. Result(s): Ages did not differ between nonelective (ne) single ET (SET), ne2-ET, and neR3-ET cycles (41.3 +/- 3.9, 41.7 +/- 3.1, and 42.4 +/- 2.1 years, respectively). Patients with neSETs demonstrated significantly lower AMH and higher FSH levels and required higher gonadotropin dosages than ne2-ET and neR3-ET patients. LBRs declined with age. Above age 42, three or more embryos are required to achieve reasonable LBRs and two or more to avoid futility under American Society for Reproductive Medicine (ASRM) guidelines. Conclusion(s): Very poor prognosis patients can still achieve acceptable pregnancy rates at least till their mid-40s if they reach ET. The degree to which egg donation is emphasized as the only treatment option in such patients, therefore, requires reconsideration. Above age 42, at least two, and preferably three embryos, are however required to exceed futility, as defined by ASRM. (C) 2015 by American Society for Reproductive Medicine.

Diphencyprone (DPCP) is a hapten that induces delayed-type hypersensitivity (DTH) reactions. MicroRNAs (miRNAs) are short non-coding RNAs that negatively regulate gene expression and have been implicated in various inflammatory skin diseases, but their role in DTH reactions is not well understood. We generated global miRNA expression profiles (using next-generation sequencing) of DPCP reactions in skin of seven healthy volunteers at 3, 14 and 120days after challenge. Compared to placebo-treated sites, DPCP-challenged skin at 3days (peak inflammation) had 127 miRNAs significantly deregulated. At 14days (during resolution of inflammation), 43 miRNAs were deregulated and, at 120days (when inflammation had completely resolved), six miRNAs were upregulated. While some miRNAs have been observed in psoriasis or atopic dermatitis, most of the deregulated miRNAs have not yet been studied in the context of skin biology or immunology. Across the three time points studied, many but not all miRNAs were uniquely expressed. As various miRNAs may influence T cell activation, this may indicate that the miRNAs exclusively expressed at different time points function to promote or resolve skin inflammation, and therefore, may inform on the paradoxical ability of DPCP to treat both autoimmune conditions (alopecia areata) and conditions of ineffective immunity (melanoma).

In this study, we developed human immune system (HIS) mice that possess functional human CD4+ T cells and B cells, named HIS-CD4/B mice. HIS-CD4/B mice were generated by first introducing HLA class II genes, including DR1 and DR4, along with genes encoding various human cytokines and human B cell activation factor (BAFF) to NSG mice by adeno-associated virus serotype 9 (AAV9) vectors, followed by engrafting human hematopoietic stem cells (HSCs). HIS-CD4/B mice, in which the reconstitution of human CD4+ T and B cells resembles to that of humans, produced a significant level of human IgG against Plasmodium faldparum circumsporozoite (PfCS) protein upon immunization. CD4+ T cells in HIS-CD4/B mice, which possess central and effector memory phenotypes like those in humans, are functional, since PfCS protein-specific human CD4+ T cells secreting IFN-gamma, and IL-2 were detected in immunized HIS-CD4/B mice. Lastly, PfCS protein-immunized HIS-CD4/B mice were protected from in vivo challenge with transgenic P. berghei sporozoites expressing the PfCS protein. The immune sera collected from protected HIS-CD4/B mice reacted against transgenic P. berghei sporozoites expressing the PfCS protein and also inhibited the parasite invasion into hepatocytes in vitro. Taken together, these studies show that our HIS-CD4/B mice could mount protective human anti-malaria immunity, consisting of human IgG and human CD4+ T cell responses both specific for a human malaria antigen. (C) 2015 Elsevier B.V. All rights reserved.

BackgroundAchieving timely accrual into clinical research studies remains a challenge for clinical translational research. We developed an evaluation measure, the Accrual Index (AI), normalized for sample size and study duration, using data from the protocol and study management databases. We applied the AI retrospectively and prospectively to assess its utility. MethodsAccrual Target, Projected Time to Accrual Completion (PTAC), Evaluable Subjects, Dates of Recruitment Initiation, Analysis, and Completion were defined. AI is (% Accrual Target accrued/% PTAC elapsed). Changes to recruitment practices were described, and data extracted from study management databases. ResultsDecember 2014 (or final) AI was analyzed for 101 studies initiating recruitment from 2007 to 2014. Median AI was 1 for protocols initiating recruitment in 2011, 2013, and 2014. The AI varied widely for studies pre-2013. Studies with AI > 4 utilized convenience samples for recruitment. Data-justified PTAC was refined in 2013-2014 after which the AI range narrowed. Protocol characteristics were not associated with study AI. ConclusionProtocol AI reflects the relative agreement between accrual feasibility assessment (PTAC), and accrual performance, and is affected by recruitment practices. The AI may be useful in managing accountability, modeling accrual, allocating recruitment resources, and testing innovations in recruitment practices.

At the eukaryotic DNA replication fork, it is widely believed that the Cdc45-Mcm2-7-GINS (CMG) helicase is positioned in front to unwind DNA and that DNA polymerases trail behind the helicase. Here we used single-particle EM to directly image a Saccharomyces cerevisiae replisome. Contrary to expectations, the leading strand Pol epsilon is positioned ahead of CMG helicase, whereas Ctf4 and the lagging-strand polymerase (Pol) alpha-primase are behind the helicase. This unexpected architecture indicates that the leading-strand DNA travels a long distance before reaching Pol epsilon, first threading through the Mcm2-7 ring and then making a U-turn at the bottom and reaching Pol a at the top of CMG. Our work reveals an unexpected configuration of the eukaryotic replisome, suggests possible reasons for this architecture and provides a basis for further structural and biochemical replisome studies.

The Mediator complex orchestrates multiple transcription factors with the Pol II apparatus for precise transcriptional control. However, its interplay with the surrounding chromatin remains poorly understood. Here, we analyze differential histone modifications between WT and MED23(-/-) (KO) cells and identify H2B mono-ubiquitination at lysine 120 (H2Bub) as a MED23-dependent histone modification. Using tandem affinity purification and mass spectrometry, we find that MED23 associates with the RNF20/40 complex, the enzyme for H2Bub, and show that this association is critical for the recruitment of RNF20/40 to chromatin. In a cell-free system, Mediator directly and substantially increases H2Bub on recombinant chromatin through its cooperation with RNF20/40 and the PAF complex. Integrative genome-wide analyses show that MED23 depletion specifically reduces H2Bub on a subset of MED23-controlled genes. Importantly, MED23-coupled H2Bub levels are oppositely regulated during myogenesis and lung carcinogenesis. In sum, these results establish a mechanistic link between the Mediator complex and a critical chromatin modification in coordinating transcription with cell growth and differentiation.