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Found 37769 matches. Displaying 4561-4570
Gleicher N, Kushnir VA, Darmon SK, Wang Q, Zhang L, Albertini DF, Barad DH
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New PCOS-like phenotype in older infertile women of likely autoimmune adrenal etiology with high AMH but low androgens

JOURNAL OF STEROID BIOCHEMISTRY AND MOLECULAR BIOLOGY 2017 MAR; 167(?):144-152
How anti-Mtillerian hormone (AMH) and testosterone (T) interrelate in infertile women is currently largely unknown. We, therefore, in a retrospective cohort study investigated how infertile women with high-AMH (AMH >= 75th quantile; n =144) and with normal-AMH (25th-75th quantile; n = 313), stratified for low-T (total testosterone <= 19.0 ng/dL), normal-T (19.0-29.0 ng/dL) and high-T (>29.0 ng/dL) phenotypically behaved. Patient age, follicle stimulating hormone (FSH), dehyroepiandrosterone (DHEA), DHEA sulphate (DHEAS), cortisol (C), adrenocorticotrophic hormone (ACTH), IVF outcomes, as well as inflammatory and immune panels were then compared between groups, with AMH and T as variables. We identified a previously unknown infertile PCOS-like phenotype, characterized by highAMH but, atypically, low-T, with predisposition toward autoimmunity. It presents with incompatible high-AMH and low-T (<19.0 ng/dL), is restricted to lean PCOS-like patients, presenting delayed for tertiary fertility services. Since also characterized by low DHEAS, low-T is likely of adrenal origina, and consequence of autoimmune adrenal insufficiency since also accompanied by low-C and evidence of autoimmunity. DHEA supplementation in such patients equalizes low- to normal-T and normalizes IVF cycle outcomes. Once recognized, this high-AMH/low-T phenotype is surprisingly common in tertiary fertility centers but, currently, goes unrecognized. Its likely adrenal autoimmune etiology offers interesting new directions for investigations of adrenals control over ovarian function via adrenal androgen production. (C) 2016 Elsevier Ltd. All rights reserved.
Westcott NP, Fernandez JP, Molina H, Hang HC
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Chemical proteomics reveals ADP-ribosylation of small GTPases during oxidative stress

NATURE CHEMICAL BIOLOGY 2017 MAR; 13(3):302-308
ADP-ribosylation is a post-translational modification that is known to be involved in cellular homeostasis and stress but has been challenging to analyze biochemically. To facilitate the detection of ADP-ribosylated proteins, we show that an alkyne-adenosine analog, N-6-propargyl adenosine (N(6)pA), is metabolically incorporated in mammalian cells and enables fluorescence detection and proteomic analysis of ADP-ribosylated proteins. Notably, our analysis of N(6)pA-labeled proteins that are upregulated by oxidative stress revealed differential ADP-ribosylation of small GTPases. We discovered that oxidative stress induced ADP-ribosylation of Hras on Cys181 and Cys184 in the C-terminal hypervariable region, which are normally S-fatty-acylated. Downstream Hras signaling is impaired by ADP-ribosylation during oxidative stress, but is rescued by ADP-ribosyltransferase inhibitors. Our study demonstrates that ADP-ribosylation of small GTPases not only is mediated by bacterial toxins but is endogenously regulated in mammalian cells. N(6)pA provides a useful tool to characterize ADP-ribosylated proteins and their regulatory mechanisms in cells.
Dunogue B, Pilmis B, Mahlaoui N, Elie C, Coignard-Biehler H, Amazzough K, Noel N, Salvator H, Catherinot E, Couderc LJ, Sokol H, Lanternier F, Fouyssac F, Bardet J, Bustamante J, Gougerot-Pocidalo MA, Barlogis V, Masseau A, Durieu I, Lecuit M, Suarez F, Fischer A, Blanche S, Hermine O, Lortholary O
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Chronic Granulomatous Disease in Patients Reaching Adulthood: A Nationwide Study in France

CLINICAL INFECTIOUS DISEASES 2017 MAR 15; 64(6):767-775
Background. Although prognosis of Chronic Granulomatous Disease (CGD) has greatly improved, few studies have focused on its long-term outcome. We studied the clinical course and sequelae of CGD patients diagnosed before age 16, at various adult time points. Method. Cross-sectional French nationwide retrospective study of patients screened through the National Reference Center for Primary Immunodeficiencies (CEREDIH) registry. Results. Eighty CGD patients (71 males [88.7%], 59 X-linked [73.7%], median age 23.9 years [minimum, 16.6; maximum, 59.9]) were included, Median ages at diagnosis and last follow-up were 2.52 and 23.9 years, respectively. Seven patients underwent hematopoietic stem cell transplantation. A total of 553 infections requiring hospitalization occurred in 2017 patient-years. The most common site of infection was pulmonary (31%). Aspergillus spp. (17%) and Staphylococcus aureus (10.7%) were the commonest pathogens. A total of 224 inflammatory episodes occurred in 71 patients, mainly digestive (50%). Their characteristics as well as their annual frequency did not vary before and after age 16. Main sequelae were a small adult height and weight and mild chronic restrictive respiratory failure. At age 16, only 53% of patients were in high school. After age 30 years, 9/13 patients were working. Ten patients died during adulthood. Conclusions. Adult CGD patients displayed similar characteristics and rates of severe infections and inflammatory episodes that those of childhood. The high rate of handicap has become a matter of medical and social consideration. Careful follow-up in centers of expertise is strongly recommended and an extended indication of curative treatment by HSCT should be considered.
Upla P, Kim SJ, Sampathkumar P, Dutta K, Cahill SM, Chemmama IE, Williams R, Bonanno JB, Rice WJ, Stokes DL, Cowburn D, Almo SC, Sali A, Rout MP, Fernandez-Martinez J
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Molecular Architecture of the Major Membrane Ring Component of the Nuclear Pore Complex

STRUCTURE 2017 MAR 7; 25(3):434-445
The membrane ring that equatorially circumscribes the nuclear pore complex (NPC) in the perinuclear lumen of the nuclear envelope is composed largely of Pom152 in yeast and its ortholog Nup210 (or Gp210) in vertebrates. Here, we have used a combination of negative-stain electron microscopy, nuclear magnetic resonance, and small-angle X-ray scattering methods to determine an integrative structure of the similar to 120 kDa luminal domain of Pom152. Our structural analysis reveals that the luminal domain is formed by a flexible string-ofpearls arrangement of nine repetitive cadherin-like Ig-like domains, indicating an evolutionary connection between NPCs and the cell adhesion machinery. The 16 copies of Pom152 known to be present in the yeast NPC are long enough to form the observed membrane ring, suggesting how interactions between Pom152 molecules help establish and maintain the NPC architecture.
Yamaji M, Jishage M, Meyer C, Suryawanshi H, Evan, Yamaji M, Garzia A, Morozov P, Manickavel S, Mcfarland HL, Roeder RG, Hafner M, Tuschl T
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DND1 maintains germline stem cells via recruitment of the CCR4-NOT complex to target mRNAs

NATURE 2017 MAR 23; 543(7646):568-572
The vertebrate-conserved RNA-binding protein DND1 is required for the survival of primordial germ cells (PGCs), as well as the suppression of germ cell tumours in mice(1-5). Here we show that in mice DND1 binds a UU(A/U) trinucleotide motif predominantly in the 3' untranslated regions of mRNA, and destabilizes target mRNAs through direct recruitment of the CCR4-NOT deadenylase complex. Transcriptomic analysis reveals that the extent of suppression is dependent on the number of DND1-binding sites. This DND1-dependent mRNA destabilization is required for the survival of mouse PGCs and spermatogonial stem cells by suppressing apoptosis. The spectrum of target RNAs includes positive regulators of apoptosis and inflammation, and modulators of signalling pathways that regulate stem-cell pluripotency, including the TGFa superfamily, all of which are aberrantly elevated in DND1-deficient PGCs. We propose that the induction of the post-transcriptional suppressor DND1 synergizes with concurrent transcriptional changes to ensure precise developmental transitions during cellular differentiation and maintenance of the germ line.
Kang JY
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Structural basis of transcription arrest by coliphage HK022 Nun in an

ELIFE 2017 MAR 20; 6(?):? Article e25478
Coliphage HK022 Nun blocks superinfection by coliphage lambda, by
Timashev LA, Babcock H, Zhuang XW, de Lange T
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The DDR at telomeres lacking intact shelterin does not require substantial chromatin decompaction

GENES & DEVELOPMENT 2017 MAR 15; 31(6):578-589
Telomeres are protected by shelterin, a six-subunit protein complex that represses the DNA damage response (DDR) at chromosome ends. Extensive data suggest that TRF2 in shelterin remodels telomeres into the t-loop structure, thereby hiding telomere ends from double-stranded break repair and ATM signaling, whereas POT1 represses ATR signaling by excluding RPA. An alternative protection mechanism was suggested recently by which shelterin subunits TRF1, TRF2, and TIN2 mediate telomeric chromatin compaction, which was proposed to minimize access of DDR factors. We performed superresolution imaging of telomeres in mouse cells after conditional deletion of TRF1, TRF2, or both, the latter of which results in the complete loss of shelterin. Upon removal of TRF1 or TRF2, we observed only minor changes in the telomere volume in most of our experiments. Upon codeletion of TRF1 and TRF2, the telomere volume increased by varying amounts, but even those samples exhibiting small changes in telomere volume showed DDR at nearly all telomeres. Upon shelterin removal, telomeres underwent 53BP1-dependent clustering, potentially explaining at least in part the apparent increase in telomere volume. Furthermore, chromatin accessibility, as determined by ATAC-seq (assay for transposase-accessible chromatin [ATAC] with high-throughput sequencing), was not substantially altered by shelterin removal. These results suggest that the DDR induced by shelterin removal does not require substantial telomere decompaction.
Ungar B
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Patch testing of food allergens promotes Th17 and Th2 responses with

EXPERIMENTAL DERMATOLOGY 2017 MAR; 26(3):272-275
Nishimura Y, Gautam R, Chun TW, Sadjadpour R, Foulds KE, Shingai M, Klein F, Gazumyan A, Golijanin J, Donaldson M, Donau OK, Plishka RJ, Buckler-White A, Seaman MS, Lifson JD, Koup RA, Fauci AS, Nussenzweig MC, Martin MA
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Early antibody therapy can induce long-lasting immunity to SHIV

NATURE 2017 MAR 23; 543(7646):559-563
Highly potent and broadly neutralizing anti-HIV-1 antibodies (bNAbs) have been used to prevent and treat lentivirus infections in humanized mice, macaques, and humans(1-12). In immunotherapy experiments, administration of bNAbs to chronically infected animals transiently suppresses virus replication, which invariably returns to pre-treatment levels and results in progression to clinical disease. Here we show that early administration of bNAbs in a macaque simian/human immunodeficiency virus (SHIV) model is associated with very low levels of persistent viraemia, which leads to the establishment of T-cell immunity and resultant longterm infection control. Animals challenged with SHIVAD8-EO by mucosal or intravenous routes received a single 2-week course of two potent passively transferred bNAbs (3BNC117 and 10-1074 (refs 13, 14)). Viraemia remained undetectable for 56-177 days, depending on bNAb half-life in vivo. Moreover, in the 13 treated monkeys, plasma virus loads subsequently declined to undetectable levels in 6 controller macaques. Four additional animals maintained their counts of T cells carrying the CD4 antigen (CD4+) and very low levels of viraemia persisted for over 2 years. The frequency of cells carrying replication-competent virus was less than 1 per 106 circulating CD4(+) T cells in the six controller macaques. Infusion of a T-cell-depleting anti-CD8 beta monoclonal antibody to the controller animals led to a specific decline in levels of CD8(+) T cells and the rapid reappearance of plasma viraemia. In contrast, macaques treated for 15 weeks with combination anti-retroviral therapy, beginning on day 3 after infection, experienced sustained rebound plasma viraemia when treatment was interrupted. Our results show that passive immunotherapy during acute SHIV infection differs from combination anti-retroviral therapy in that it facilitates the emergence of potent CD8(+) T-cell immunity able to durably suppress virus replication.
Rommel PC, Oliveira TY, Nussenzweig MC, Robbiani DF
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RAG1/2 induces genomic insertions by mobilizing DNA into RAG1/2-independent breaks

JOURNAL OF EXPERIMENTAL MEDICINE 2017 MAR; 214(3):815-831
The RAG recombinase (RAG1/2) plays an essential role in adaptive immunity by mediating V(D)J recombination in developing lymphocytes. In contrast, aberrant RAG1/2 activity promotes lymphocyte malignancies by causing chromosomal translocations and DNA deletions at cancer genes. RAG1/2 can also induce genomic DNA insertions by transposition and trans-V(D)J recombination, but only few such putative events have been documented in vivo. We used next-generation sequencing techniques to examine chromosomal rearrangements in primary murine B cells and discovered that RAG1/2 causes aberrant insertions by releasing cleaved antibody gene fragments that subsequently reintegrate into DNA breaks induced on a heterologous chromosome. We confirmed that RAG1/2 also mobilizes genomic DNA into independent physiological breaks by identifying similar insertions in human lymphoma and leukemia. Our findings reveal a novel RAG1/2-mediated insertion pathway distinct from DNA transposition and trans-V(D)J recombination that destabilizes the genome and shares features with reported oncogenic DNA insertions.