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Conceicao T, Coelho C, de Lencastre H, Aires-de-Sousa M
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Frequent occurrence of oxacillin-susceptible mecA-positive Staphylococcus aureus (OS-MRSA) strains in two African countries

JOURNAL OF ANTIMICROBIAL CHEMOTHERAPY 2015 DEC; 70(12):3200-3204
Background: Oxacillin-susceptible mecA-positive Staphylococcus aureus (OS-MRSA) isolates have been increasingly reported worldwide, but data regarding the African continent have not been available. Methods: Between 2010 and 2014, 1462 inpatients and healthcare workers were screened for MRSA nasal carriage in Sao Tome and Principe (STP) and Angola, two Portuguese-speaking African countries (PALOP countries). We determined the presence of the mecA gene and the antimicrobial susceptibility profiles of the isolates. OS-MRSA clonal lineages were identified as well as the presence of virulence determinants, including Panton-Valentine leucocidin (PVL). Results: Out of 164 S. aureus hospital isolates tested, 29 (17.7%) were mecA positive, but susceptible to oxacillin, showing oxacillin MICs <= 3 mg/L. All OS-MRSA isolates were resistant to cefoxitin and most of them were also resistant to at least two antimicrobials other than beta-lactams. The 29 OS-MRSA were distributed into two major clonal lineages: (i) PFGE type B-ST88-SCCmec IVa, associated with spa types t186/t325/t786/t1814/t1951, detected in Angola (n = 5) and STP (n = 10); and (ii) PFGE type C-t451/t648-ST8-SCCmec V, exclusively found in STP (n = 9). OS-MRSA showed at least two virulence determinants. PVL was detected in an isolate recovered in STP. Conclusions: We describe a high prevalence of OS-MRSA among S. aureus strains recovered in two African countries. OS-MRSA in PALOP countries were mainly associated with ST88 and ST8, two prevalent MRSA clonal types in these countries. If direct testing for mecA is not available, cefoxitin susceptibility testing is highly recommended to avoid the misidentification of OS-MRSA.
Gleicher N, Vega MV, Darmon SK, Weghofer A, Wu YG, Wang Q, Zhang L, Albertini DF, Barad DH, Kushnir VA
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Live-birth rates in very poor prognosis patients, who are defined as poor responders under the Bologna criteria, with nonelective single embryo, two-embryo, and three or more embryos transferred

FERTILITY AND STERILITY 2015 DEC; 104(6):1435-1441
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.
Nasca C, Zelli D, Bigio B, Piccinin S, Scaccianoce S, Nistico R, McEwen BS
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Stress dynamically regulates behavior and glutamatergic gene expression in hippocampus by opening a window of epigenetic plasticity

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 2015 DEC 1; 112(48):14960-14965
Excitatory amino acids play a key role in both adaptive and deleterious effects of stressors on the brain, and dysregulated glutamate homeostasis has been associated with psychiatric and neurological disorders. Here, we elucidate mechanisms of epigenetic plasticity in the hippocampus in the interactions between a history of chronic stress and familiar and novel acute stressors that alter expression of anxiety- and depressive-like behaviors. We demonstrate that acute restraint and acute forced swim stressors induce differential effects on these behaviors in naive mice and in mice with a history of chronic-restraint stress (CRS). They reveal a key role for epigenetic up-and down-regulation of the putative presynaptic type 2 metabotropic glutamate (mGlu2) receptors and the postsynaptic NR1/NMDA receptors in the hippocampus and particularly in the dentate gyrus (DG), a region of active neurogenesis and a target of antidepressant treatment. We show changes in DG long-term potentiation (LTP) that parallel behavioral responses, with habituation to the same acute restraint stressor and sensitization to a novel forced-swim stressor. In WT mice after CRS and in unstressed mice with a BDNF loss-of-function allele (BDNF Val66Met), we show that the epigenetic activator of histone acetylation, P300, plays a pivotal role in the dynamic up- and down-regulation of mGlu2 in hippocampus via histone-3-lysine-27-acetylation (H3K27Ac) when acute stressors are applied. These hippocampal responses reveal a window of epigenetic plasticity that may be useful for treatment of disorders in which glutamatergic transmission is dysregulated.
Fiscella K, Ogedegbe G, He H, Carroll J, Cassells A, Sanders M, Khalida C, D'Orazio B, Tobin JN
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Blood Pressure Visit Intensification Study in Treatment: Trial design

AMERICAN HEART JOURNAL 2015 DEC; 170(6):1202-1210
Background There is a presumption that, for patients with uncontrolled blood pressure (BP), early follow-up, that is, within 4 weeks of an elevated reading, improves BP control. However, data are lacking regarding effective interventions for increasing clinician frequency of follow-up visits and whether such interventions improve BP control. Methods/design Blood Pressure Visit Intensification Study in Treatment involves a multimodal approach to improving intensity of follow-up in 12 community health centers using a stepped wedge study design. Discussion The study will inform effective interventions for increasing frequency of follow-up visits among patients with uncontrolled BP and determine whether increasing follow-up frequency is associated with better BP control.
Chekler ELP, Pellegrino JA, Lanz TA, Denny RA, Flick AC, Coe J, Langille J, Basak A, Liu SP, Stock IA, Sahasrabudhe P, Bonin PD, Lee K, Pletcher MT, Jones LH
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Transcriptional Profiling of a Selective CREB Binding Protein Bromodomain Inhibitor Highlights Therapeutic Opportunities

CHEMISTRY & BIOLOGY 2015 DEC 17; 22(12):1588-1596
Bromodomains are involved in transcriptional regulation through the recognition of acetyl lysine modifications on diverse proteins. Selective pharmacological modulators of bromodomains are lacking, although the largely hydrophobic nature of the pocket makes these modules attractive targets for small-molecule inhibitors. This work describes the structure-based design of a highly selective inhibitor of the CREB binding protein (CBP) bromodomain and its use in cell-based transcriptional profiling experiments. The inhibitor downregulated a number of inflammatory genes in macrophages that were not affected by a selective BET bromodomain inhibitor. In addition, the CBP bromodomain inhibitor modulated the mRNA level of the regulator of G-protein signaling 4 (RGS4) gene in neurons, suggesting a potential therapeutic opportunity for CBP inhibitors in the treatment of neurological disorders.
Yao X, Tang ZY, Fu X, Yin JW, Liang Y, Li CH, Li HY, Tian Q, Roeder RG, Wang G
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The Mediator subunit MED23 couples H2B mono-ubiquitination to transcriptional control and cell fate determination

EMBO JOURNAL 2015 DEC 2; 34(23):2885-2902
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.
Corregano L, Bastert K, da Rosa JC, Kost RG
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Accrual Index: A Real-Time Measure of the Timeliness of Clinical Study Enrollment

CTS-CLINICAL AND TRANSLATIONAL SCIENCE 2015 DEC; 8(6):655-661
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.
About F, Oudot-Mellakh T, Niay J, Rabiega P, Pedergnana V, Duffy D, Sultanik P, Cagnot C, Carrat F, Marcellin P, Zoulim F, Larrey D, Hezode C, Fontaine H, Bronowicki JP, Pol S, Albert ML, Theodorou I, Cobat A, Abel L
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Impact of IL28B, APOH and ITPA Polymorphisms on Efficacy and Safety of TVR- or BOC-Based Triple Therapy in Treatment-Experienced HCV-1 Patients with Compensated Cirrhosis from the ANRS CO20-CUPIC Study

PLOS ONE 2015 DEC 15; 10(12):? Article e0145105
Background Human genetic factors influence the outcome of pegylated interferon and ribavirin hepatitis C therapy. We explored the role of IL28B, APOH and ITPA SNPs on the outcomes of triple therapy including telaprevir or boceprevir in patients with compensated cirrhosis chronically infected with HCV-1. Patients and Methods A total of 256 HCV-1 Caucasian treatment-experienced patients with compensated cirrhosis from the ANRS CO20-CUPIC cohort were genotyped for a total of 10 candidate SNPs in IL28B (rs12979860 and rs368234815), APOH (rs8178822, rs12944940, rs10048158, rs52797880, rs1801689 and rs1801690) and ITPA (rs1127354 and rs7270101). We tested the association of IL28B and APOH SNPs with sustained virological response and of ITPA SNPs with anemia related phenotypes by means of logistic regression assuming an additive genetic model. Results None of the six APOH SNPs were associated with sustained virological response. The favorable alleles of the IL28B SNPs rs12979860 and rs368234815 were associated with sustained virological response (rs12979860: OR = 2.35[1.50-3.70], P = 2x10(-4)). Refined analysis showed that the effect of IL28B SNPs on sustained virological response was restricted to prior PegIFN/RBV relapse (OR = 3.80[1.82-8.92], P = 8x10(-4)). We also confirmed the association between ITPA low activity alleles and protection against early hemoglobin decline in triple therapy (P = 2x10(-5)). Conclusion Our results suggest that the screening of rs12979860 may remain interesting for decision making in prior relapse HCV-1 Caucasian patients with compensated cirrhosis eligible for a telaprevir-or boceprevir-based therapy.
Hernandez-Enriquez B, Wu ZH, Martinez E, Olsen O, Kaprielian Z, Maness PF, Yoshida Y, Tessier-Lavigne M, Tran TS
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Floor plate-derived neuropilin-2 functions as a secreted semaphorin sink to facilitate commissural axon midline crossing

GENES & DEVELOPMENT 2015 DEC 15; 29(24):2617-2632
Commissural axon guidance depends on a myriad of cues expressed by intermediate targets. Secreted semaphorins signal through neuropilin-2/plexin-A1 receptor complexes on post-crossing commissural axons to mediate floor plate repulsion in the mouse spinal cord. Here, we show that neuropilin-2/plexin-A1 are also coexpressed on commissural axons prior to midline crossing and can mediate precrossing semaphorin-induced repulsion in vitro. How premature semaphorin-induced repulsion of precrossing axons is suppressed in vivo is not known. We discovered that a novel source of floor plate-derived, but not axon-derived, neuropilin-2 is required for precrossing axon pathfinding. Floor plate-specific deletion of neuropilin-2 significantly reduces the presence of precrossing axons in the ventral spinal cord, which can be rescued by inhibiting plexin-A1 signaling in vivo. Our results show that floor plate-derived neuropilin-2 is developmentally regulated, functioning as a molecular sink to sequester semaphorins, preventing premature repulsion of precrossing axons prior to subsequent down-regulation, and allowing for semaphorin-mediated repulsion of post-crossing axons.
Schulz D, Mugnier MR, Paulsen EM, Kim HS, Chung CWW, Tough DF, Rioja I, Prinjha RK, Papavasiliou FN, Debler EW
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Bromodomain Proteins Contribute to Maintenance of Bloodstream Form Stage Identity in the African Trypanosome

PLOS BIOLOGY 2015 DEC; 13(12):? Article e1002316
Trypanosoma brucei, the causative agent of African sleeping sickness, is transmitted to its mammalian host by the tsetse. In the fly, the parasite's surface is covered with invariant procyclin, while in the mammal it resides extracellularly in its bloodstream form (BF) and is densely covered with highly immunogenic Variant Surface Glycoprotein (VSG). In the BF, the parasite varies this highly immunogenic surface VSG using a repertoire of similar to 2500 distinct VSG genes. Recent reports in mammalian systems point to a role for histone acetyl-lysine recognizing bromodomain proteins in the maintenance of stem cell fate, leading us to hypothesize that bromodomain proteins may maintain the BF cell fate in trypanosomes. Using small-molecule inhibitors and genetic mutants for individual bromodomain proteins, we performed RNA-seq experiments that revealed changes in the transcriptome similar to those seen in cells differentiating from the BF to the insect stage. This was recapitulated at the protein level by the appearance of insect-stage proteins on the cell surface. Furthermore, bromodomain inhibition disrupts two major BF-specific immune evasion mechanisms that trypanosomes harness to evade mammalian host antibody responses. First, monoallelic expression of the antigenically varied VSG is disrupted. Second, rapid internalization of antibodies bound to VSG on the surface of the trypanosome is blocked. Thus, our studies reveal a role for trypanosome bromodomain proteins in maintaining bloodstream stage identity and immune evasion. Importantly, bromodomain inhibition leads to a decrease in virulence in a mouse model of infection, establishing these proteins as potential therapeutic drug targets for trypanosomiasis. Our 1.25A resolution crystal structure of a trypanosome bromodomain in complex with I-BET151 reveals a novel binding mode of the inhibitor, which serves as a promising starting point for rational drug design.