Publications search

Found 37769 matches. Displaying 5151-5160
Toubiana J, Okada S, Hiller J, Oleastro M, Gomez ML, Becerra JCA, Ouachee-Chardin M, Fouyssac F, Girisha KM, Etzioni A, Van Montfrans J, Camcioglu Y, Kerns LA, Belohradsky B, Blanche S, Bousfiha A, Rodriguez-Gallego C, Meyts I, Kisand K, Reichenbach J, Renner ED, Rosenzweig S, Grimbacher B, van de Veerdonk FL, Traidl-Hoffmann C, Picard C, Marodi L, Morio T, Kobayashi M, Lilic D, Milner JD, Holland S, Casanova JL, Puel A
Show All Authors

Heterozygous STAT1 gain-of-function mutations underlie an unexpectedly broad clinical phenotype

BLOOD 2016 JUN 23; 127(25):3154-3164
Since their discovery in patients with autosomal dominant (AD) chronic mucocutaneous candidiasis (CMC) in 2011, heterozygous STAT1 gain-of-function (GOF) mutations have increasingly been identified worldwide. The clinical spectrum associated with them needed to be delineated. We enrolled 274 patients from 167 kindreds originating from 40 countries from 5 continents. Demographic data, clinical features, immunological parameters, treatment, and outcome were recorded. The median age of the 274 patients was 22 years (range, 1-71 years); 98% of them had CMC, with a median age at onset of 1 year (range, 0-24 years). Patients often displayed bacterial (74%) infections, mostly because of Staphylococcus aureus (36%), including the respiratory tract and the skin in 47% and 28% of patients, respectively, and viral (38%) infections, mostly because of Herpesviridae (83%) and affecting the skin in 32% of patients. Invasive fungal infections (10%), mostly caused by Candida spp. (29%), and mycobacterial disease (6%) caused by Mycobacterium tuberculosis, environmental mycobacteria, or Bacille Calmette-Guerin vaccines were less common. Many patients had autoimmune manifestations (37%), including hypothyroidism(22%), type 1 diabetes (4%), blood cytopenia (4%), and systemic lupus erythematosus (2%). Invasive infections (25%), cerebral aneurysms(6%), and cancers (6%) were the strongest predictors of poor outcome. CMC persisted in 39% of the 202 patients receiving prolonged antifungal treatment. Circulating interleukin-17A-producing T-cell count was low for most (82%) but not all of the patients tested. STAT1 GOF mutations underlie AD CMC, as well as an unexpectedly wide range of other clinical features, including not only a variety of infectious and autoimmune diseases, but also cerebral aneurysms and carcinomas that confer a poor prognosis.
Ser Z, Gao X, Johnson C, Mehrmohamadi M, Liu XJ, Li SQ, Locasale JW
Show All Authors

Targeting One Carbon Metabolism with an Antimetabolite Disrupts Pyrimidine Homeostasis and Induces Nucleotide Overflow

CELL REPORTS 2016 JUN 14; 15(11):2367-2376
Antimetabolites that affect nucleotide metabolism are frontline chemotherapy agents in several cancers and often successfully target one carbon metabolism. However, the precise mechanisms and resulting determinants of their therapeutic value are unknown. We show that 5-fluorouracil (5-FU), a commonly used antimetabolite therapeutic with varying efficacy, induces specific alterations to nucleotide metabolism by disrupting pyrimidine homeostasis. An integrative metabolomics analysis of the cellular response to 5-FU reveals intracellular uracil accumulation, whereas deoxyuridine levels exhibited increased flux into the extracellular space, resulting in an induction of overflow metabolism. Subsequent analysis from mice bearing colorectal tumors treated with 5-FU show specific secretion of metabolites in tumor-bearing mice into serum that results from alterations in nucleotide flux and reduction in overflowmetabolism. Together, these findings identify a determinant of an antimetabolite response that may be exploited to more precisely define the tumors that could respond to targeting cancer metabolism.
Mende M, Fletcher EV, Belluardo JL, Pierce JP, Bommareddy PK, Weinrich JA, Kabir ZD, Schierberl KC, Pagiazitis JG, Mendelsohn AI, Francesconi A, Edwards RH, Milner TA, Rajadhyaksha AM, van Roessel PJ, Mentis GZ, Kaltschmidt JA
Show All Authors

Sensory-Derived Glutamate Regulates Presynaptic Inhibitory Terminals in Mouse Spinal Cord

NEURON 2016 JUN 15; 90(6):1189-1202
Circuit function in the CNS relies on the balanced interplay of excitatory and inhibitory synaptic signaling. How neuronal activity influences synaptic differentiation to maintain such balance remains unclear. In the mouse spinal cord, a population of GABAergic interneurons, GABApre, forms synapses with the terminals of proprioceptive sensory neurons and controls information transfer at sensory-motor connections through presynaptic inhibition. We show that reducing sensory glutamate release results in decreased expression of GABA-synthesizing enzymes GAD65 and GAD67 in GABApre terminals and decreased presynaptic inhibition. Glutamate directs GAD67 expression via the metabotropic glutamate receptor mGluR1b on GABApre terminals and regulates GAD65 expression via autocrine influence on sensory terminal BDNF. We demonstrate that dual retrograde signals from sensory terminals operate hierarchically to direct the molecular differentiation of GABApre terminals and the efficacy of presynaptic inhibition. These retrograde signals comprise a feedback mechanism by which excitatory sensory activity drives GABAergic inhibition to maintain circuit homeostasis.
Maffucci P, Filion CA, Boisson B, Itan Y, Shang L, Casanova JL, Cunningham-Rundles C
Show All Authors

Genetic Diagnosis Using Whole Exome Sequencing in Common Variable Immunodeficiency

FRONTIERS IN IMMUNOLOGY 2016 JUN 13; 7(?):? Article 220
Whole exome sequencing (WES) has proven an effective tool for the discovery of genetic defects in patients with primary immunodeficiencies (PIDs). However, success in dissecting the genetic etiology of common variable immunodeficiency (CVID) has been limited. We outline a practical framework for using WES to identify causative genetic defects in these subjects. WES was performed on 50 subjects diagnosed with CVID who had at least one of the following criteria: early onset, autoimmune/inflammatory manifestations, low B lymphocytes, and/or familial history of hypogammaglobulinemia. Following alignment and variant calling, exomes were screened for mutations in 269 PID-causing genes. Variants were filtered based on the mode of inheritance and reported frequency in the general population. Each variant was assessed by study of familial segregation and computational predictions of deleteriousness. Out of 433 variations in PID-associated genes, we identified 17 probable disease-causing mutations in 15 patients (30%). These variations were rare or private and included monoallelic mutations in NFKB1, STAT3, CTLA4, PIK3CD, and IKZF1, and biallelic mutations in LRBA and STXBP2. Forty-two other damaging variants were found but were not considered likely disease-causing based on the mode of inheritance and/or patient phenotype. WES combined with analysis of PID-associated genes is a cost-effective approach to identify disease-causing mutations in CVID patients with severe phenotypes and was successful in 30% of our cohort. As targeted therapeutics are becoming the mainstay of treatment for non-infectious manifestations in CVID, this approach will improve management of patients with more severe phenotypes.
Simoes AS, Tavares DA, Rolo D, Ardanuy C, Goossens H, Henriques-Normark B, Linares J, de Lencastre H, Sa-Leao R
Show All Authors

lytA-based identification methods can misidentify Streptococcus pneumoniae

DIAGNOSTIC MICROBIOLOGY AND INFECTIOUS DISEASE 2016 JUN; 85(2):141-148
During surveillance studies we detected, among over 1500 presumptive pneumococci, 11 isolates displaying conflicting or novel results when characterized by widely accepted phenotypic (optochin susceptibility and bile solubility) and genotypic (lytA-BsaAI-RFLP and MLST) identification methods. We aimed to determine the genetic basis for the unexpected results given by lytA-BsaAl-RFLP and investigate the accuracy of the WHO recommended lytA real-time PCR assay to classify these 11 isolates. Three novel lytA-BsaAI-RFLP signatures were found (one in pneumococcus and two in S. mitts). In addition, one pneumococcus displayed the atypical lytA-BsaAl-RFLP signature characteristic of non-pneumococci and two S. pseudopneumoniae displayed the typical lytA-BsaAl-RFLP pattern characteristic of pneumococci. lytA real-time PCR misidentified these three isolates. In conclusion, identification of pneumococci by lytA real-time PCR, and other lytA-based methodologies, may lead to false results. This is of particular relevance in the increasingly frequent colonization studies relying solely on culture independent methods. (C) 2016 Elsevier Inc. All rights reserved.
Li L, Pan ZF, Huang X, Wu BW, Li T, Kang MX, Ge RS, Hu XY, Zhang YH, Ge LJ, Zhu DY, Wu YL, Lou YJ
Show All Authors

Junctophilin 3 expresses in pancreatic beta cells and is required for glucose-stimulated insulin secretion

CELL DEATH & DISEASE 2016 JUN; 7(?):? Article e2275
It is well accepted that junctophilin (JPHs) isoforms act as a physical bridge linking plasma membrane and endoplasmic reticulum (ER) for channel crosstalk in excitable cells. Our purpose is to investigate whether JPHs are involved in the proper communication between Ca2+ influx and subsequent Ca2+ amplification in pancreatic beta cells, thereby participating in regulating insulin secretion. The expression of JPH isoforms was examined in human and mouse pancreatic tissues, and JPH3 expression was found in both the beta cells. In mice, knockdown of Jph3 (si-Jph3) in islets decreased glucose-stimulated insulin secretion (GSIS) accompanied by mitochondrial function impairment. Si-Jph3 lowered the insulin secretory response to Ca2+ signaling in the presence of glucose, and reduced [Ca2+] c transient amplitude triggered by caffeine. Si-Jph3 also attenuated mitofusin 2 expression, thereby disturbing the spatial organization of ER-mitochondria contact in islets. These results suggest that the regulation of GSIS by the KATP channel-independent pathways is partly impaired due to decrease of JPH3 expression in mouse islets. JPH3 also binds to type 2 ryanodine receptors (RyR2) in mouse and human pancreatic tissues, which might contribute to Ca2+ release amplification in GSIS. This study demonstrates some previously unrecognized findings in pancreatic tissues: (1) JPH3 expresses in mouse and human beta cells; (2) si-Jph3 in mouse primary islets impairs GSIS in vitro; (3) impairment in GSIS in si-Jph3 islets is due to changes in RyR2-[Ca2+] c transient amplitude and ER-mitochondria contact.
Mesalam AA, Vercauteren K, Meuleman P
Show All Authors

Mouse Systems to Model Hepatitis C Virus Treatment and Associated Resistance

VIRUSES-BASEL 2016 JUN; 8(6):? Article 176
While addition of the first-approved protease inhibitors (PIs), telaprevir and boceprevir, to pegylated interferon (PEG-IFN) and ribavirin (RBV) combination therapy significantly increased sustained virologic response (SVR) rates, PI-based triple therapy for the treatment of chronic hepatitis C virus (HCV) infection was prone to the emergence of resistant viral variants. Meanwhile, multiple direct acting antiviral agents (DAAs) targeting either the HCV NS3/4A protease, NS5A or NS5B polymerase have been approved and these have varying potencies and distinct propensities to provoke resistance. The pre-clinical in vivo assessment of drug efficacy and resistant variant emergence underwent a great evolution over the last decade. This field had long been hampered by the lack of suitable small animal models that robustly support the entire HCV life cycle. In particular, chimeric mice with humanized livers (humanized mice) and chimpanzees have been instrumental for studying HCV inhibitors and the evolution of drug resistance. In this review, we present the different in vivo HCV infection models and discuss their applicability to assess HCV therapy response and emergence of resistant variants.
Kushnir VA, Solouki S, Sarig-Meth T, Vega MG, Albertini DF, Darmon SK, Deligdisch L, Barad DH, Gleicher N
Show All Authors

Systemic Inflammation and Autoimmunity in Women with Chronic Endometritis

AMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY 2016 JUN; 75(6):672-677
Problem To determine in women with recurrent pregnancy loss (RPL) and/or implantation failure (RIF) the prevalence of chronic endometritis (CE), systemic inflammation and autoimmunity, and whether they relate. Method of Study This retrospective study examined inflammatory (adiponectin, CRP, leptin, and IL6) and autoimmune (total immunoglobulins, ANA, thyroid antibodies, antiphospholipid antibodies) markers in a group of 55 women with RPL/RIF. A diagnosis of CE was reached by endometrial biopsy, demonstrating CD138-positive plasma cells on histology. The prevalence of markers of systemic inflammation and autoimmunity was compared between women with and without CE. Results Among all RPL/RIF patients, 32.7% demonstrated at least one positive inflammatory marker, 61.8% at least one autoimmune marker, and 45.5% CE. Moreover, CE patients did not differ in systematic inflammatory or autoimmune profiles from those without CE. Conclusions Endometritis and elevated inflammatory and autoimmune markers are common in women with RPL/RIF, but endometritis cannot be predicted based on either peripheral inflammatory or autoimmune markers.
Renier N, Adams EL, Kirst C, Wu ZH, Azevedo R, Kohl J, Autry AE, Kadiri L, Venkataraju KU, Zhou Y, Wang VX, Tang CY, Olsen O, Dulac C, Osten P, Tessier-Lavigne M
Show All Authors

Mapping of Brain Activity by Automated Volume Analysis of Immediate Early Genes

CELL 2016 JUN 16; 165(7):1789-1802
Understanding how neural information is processed in physiological and pathological states would benefit from precise detection, localization, and quantification of the activity of all neurons across the entire brain, which has not, to date, been achieved in the mammalian brain. We introduce a pipeline for high-speed acquisition of brain activity at cellular resolution through profiling immediate early gene expression using immunostaining and light-sheet fluorescence imaging, followed by automated mapping and analysis of activity by an open-source software program we term ClearMap. We validate the pipeline first by analysis of brain regions activated in response to haloperidol. Next, we report new cortical regions downstream of whisker-evoked sensory processing during active exploration. Last, we combine activity mapping with axon tracing to un-cover new brain regions differentially activated during parenting behavior. This pipeline is widely applicable to different experimental paradigms, including animal species for which transgenic activity reporters are not readily available.
Creemer OJ, Ansari-Pour N, Ekong R, Tarekegn A, Plaster C, Bains RK, Itan Y, Bekele E, Bradman N
Show All Authors

Contrasting exome constancy and regulatory region variation in the gene encoding CYP3A4: an examination of the extent and potential implications

PHARMACOGENETICS AND GENOMICS 2016 JUN; 26(6):255-270
Objective CYP3A4 expression varies up to 100-fold among individuals, and, to date, genetic causes remain elusive. As a major drug-metabolizing enzyme, elucidation of such genetic causes would increase the potential for introducing personalized dose adjustment of therapies involving CYP3A4 drug substrates. The foetal CYP3A isoform, CYP3A7, is reported to be expressed in similar to 10% of European adults and may thus contribute towards the metabolism of endogenous substances and CYP3A drug substrates. However, little is known about the distribution of the variant expressed in the adult. Methods We resequenced the exons, flanking introns, regulatory elements and 3'UTR of CYP3A4 in five Ethiopian populations and incorporated data from the 1000 Genomes Project. Using bioinformatic analysis, we assessed likely consequences of observed CYP3A4 genomic variation. We also conducted the first extensive geographic survey of alleles associated with adult expression of CYP3A7 - that is, CYP3A7*1B and CYP3A7*1C. Results and conclusion Ethiopia contained 60 CYP3A4 variants (26 novel) and more variants (>1%) than all non-African populations combined. No nonsynonymous mutation was found in the homozygous form or at more than 2.8% in any population. Seventy-nine per cent of haplotypes contained 3'UTR and/or regulatory region variation with striking pairwise population differentiation, highlighting the potential for interethnic variation in CYP3A4 expression. Conversely, coding region variation showed that significant interethnic variation is unlikely at the protein level. CYP3A7*1C was found at up to 17.5% in North African populations and in significant linkage disequilibrium with CYP3A5*3, indicating that adult expression of the foetal isoform is likely to be accompanied by reduced or null expression of CYP3A5. (C) 2016 Wolters Kluwer Health, Inc. All rights reserved.