61 research outputs found

    A truncating variant of RAD51B associated with primary ovarian insufficiency provides insights into its meiotic and somatic functions

    Get PDF
    Primary ovarian insufficiency (POI) causes female infertility by abolishing normal ovarian function. Although its genetic etiology has been extensively investigated, most POI cases remain unexplained. Using whole-exome sequencing, we identified a homozygous variant in RAD51B –(c.92delT) in two sisters with POI. In vitro studies revealed that this variant leads to translation reinitiation at methionine 64. Here, we show that this is a pathogenic hypomorphic variant in a mouse model. Rad51bc.92delT/c.92delT mice exhibited meiotic DNA repair defects due to RAD51 and HSF2BP/BMRE1 accumulation in the chromosome axes leading to a reduction in the number of crossovers. Interestingly, the interaction of RAD51B-c.92delT with RAD51C and with its newly identified interactors RAD51 and HELQ was abrogated or diminished. Repair of mitomycin-C-induced chromosomal aberrations was impaired in RAD51B/Rad51b-c.92delT human and mouse somatic cells in vitro and in explanted mouse bone marrow cells. Accordingly, Rad51b-c.92delT variant reduced replication fork progression of patient-derived lymphoblastoid cell lines and pluripotent reprogramming efficiency of primary mouse embryonic fibroblasts. Finally, Rad51bc.92delT/c.92delT mice displayed increased incidence of pituitary gland hyperplasia. These results provide new mechanistic insights into the role of RAD51B not only in meiosis but in the maintenance of somatic genome stability.This work was supported by the Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Grant 2014/14231-0 (to MMF); FAPESP Grant 2013/02162-8, Nucleo de Estudos e Terapia Celular e Molecular (NETCEM), Conselho Nacional de Desenvolvimento Científico e Tecnológico Grant 303002/2016- 6 (to BBM); and FAPESP Grant 2014/50137-5 (to SELA). This work was supported by MINECO (PID2020-120326RB-I00) and by Junta de Castilla y León (CSI239P18 and CSI148P20). NFM, FSS, and MRMH are supported by European Social Fund/JCyLe grants (EDU/310/2015, EDU/556/2019 and EDU/1992/2020). YBC and RSU are funded by a grant from MINECO (BS-2015–073993 and BFU2017-89408-R). Experiments performed at CNIO were supported by grant PID2019-106707-RB to JM, co-sponsored by EU ERDF funds. SM was supported by an international postdoctoral contract “CNIO Friends”. The proteomic analysis was performed in the Proteomics Facility of Centro de Investigación del Cáncer, Salamanca, Grant PRB3(IPT17/0019 -ISCIII-SGEFI/ERDF). CIC-IBMCC is supported by the Programa de Apoyo a Planes Estratégicos de Investigación de Estructuras de Investigación de Excelencia cofunded by the Castilla–León autonomous government and the European Regional Development Fund (CLC–2017–01). Veitia’s Lab is supported by the University of Paris and the Centre National de la Recherche Scientifique

    Models and Observations of Sunspot Penumbrae

    Get PDF
    The mysteries of sunspot penumbrae have been under an intense scrutiny for the past 10 years. During this time, some models have been proposed and refuted, while the surviving ones had to be modified, adapted and evolved to explain the ever-increasing array of observational constraints. In this contribution I will review two of the present models, emphasizing their contributions to this field, but also pinpointing some of their inadequacies to explain a number of recent observations at very high spatial resolution. To help explaining these new observations I propose some modifications to each of them. These modifications bring those two seemingly opposite models closer together into a general picture that agrees well with recent 3D magneto-hydrodynamic simulations.Comment: 9 pages, 1 color figure. Review talk to appear in the proceedings of the International Workshop of 2008 Solar Total Eclipse: Solar Magnetism, Corona and Space Weather--Chinese Space Solar Telescope Scienc

    Steroid hormone-related polymorphisms associate with the development of bone erosions in rheumatoid arthritis and help to predict disease progression: Results from the REPAIR consortium

    Get PDF
    Here, we assessed whether 41 SNPs within steroid hormone genes associated with erosive disease. The most relevant finding was the rheumatoid factor (RF)-specific effect of the CYP1B1, CYP2C9, ESR2, FcγR3A, and SHBG SNPs to modulate the risk of bone erosions (P = 0.004, 0.0007, 0.0002, 0.013 and 0.015) that was confirmed through meta-analysis of our data with those from the DREAM registry (P = 0.000081, 0.0022, 0.00074, 0.0067 and 0.0087, respectively). Mechanistically, we also found a gender-specific correlation of the CYP2C9rs1799853T/T genotype with serum vitamin D3 levels (P = 0.00085) and a modest effect on IL1β levels after stimulation of PBMCs or blood with LPS and PHA (P = 0.0057 and P = 0.0058). An overall haplotype analysis also showed an association of 3 ESR1 haplotypes with a reduced risk of erosive arthritis (P = 0.009, P = 0.002, and P = 0.002). Furthermore, we observed that the ESR2, ESR1 and FcγR3A SNPs influenced the immune response after stimulation of PBMCs or macrophages with LPS or Pam3Cys (P = 0.002, 0.0008, 0.0011 and 1.97•10−7). Finally, we found that a model built with steroid hormone-related SNPs significantly improved the prediction of erosive disease in seropositive patients (PRF+ = 2.46•10−8) whereas no prediction was detected in seronegative patients (PRF− = 0.36). Although the predictive ability of the model was substantially lower in the replication population (PRF+ = 0.014), we could confirm that CYP1B1 and CYP2C9 SNPs help to predict erosive disease in seropositive patients. These results are the first to suggest a RF-specific association of steroid hormone-related polymorphisms with erosive disease

    IL-10 overexpression predisposes to invasive aspergillosis by suppressing antifungal immunity

    Get PDF
    © 2017 American Academy of Allergy, Asthma & ImmunologyProinflammatory immune responses are critically required for antimicrobial host defenses; however, excessive inflammation has the potential to damage host tissues thereby paradoxically contributing to the progression of infection. A central negative regulator of inflammatory responses is IL-10, an immunosuppressive cytokine with a wide variety of functions across multiple cell types. Although the role of IL-10 during infection appears to vary for different microorganisms, a largely detrimental role has been attributed to this cytokine during fungal disease. Given the variable risk of infection and its outcome among patients with comparable predisposing factors, susceptibility to invasive aspergillosis (IA) is thought to rely largely on genetic predisposition. The initial investigation of genetic variability at the IL10 locus led to the identification of single nucleotide polymorphisms (SNPs) influencing its transcriptional activity; thus, IL-10 may be a reasonable candidate for the genetic regulation of susceptibility to IA in high-risk patients.Supported by the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (FEDER) (NORTE-01-0145-FEDER-000013), the Fundação para a Ciência e Tecnologia (FCT) (contracts IF/00735/2014 to A.C., IF/01390/2014 to E.T., IF/00021/2014 to R.S., and SFRH/BPD/96176/2013 to C.C.), the Conselho de Reitores das Universidades Portuguesas (CRUP), Portugal (Ações Integradas Luso-Alemãs A-43/16), the Deutscher Akademischer Austauschdienst (DAAD) (project-ID 57212690), the Fondo de Investigaciones Sanitarias (Madrid, Spain) (grant #PI12/02688) and the ERA-NET PathoGenoMics (grant #0315900A).info:eu-repo/semantics/publishedVersio

    New Alloying Systems for Sintered Steels: Critical Aspects of Sintering Behavior

    Get PDF
    Oxygen-sensitive alloying elements such as Mn, Si, and Cr have a high potential for improving the properties of low alloyed sintered steels while reducing the alloying cost. However, it is necessary to find a way for avoiding, or at least minimizing, the oxidation of these elements especially during the early stages of the sintering cycle. In this study Mn, Si, and Cr were introduced in the form of a master alloy powder designed to be mixed with the iron base powder and provide the final composition of the steel during the sintering process. The reduction/oxidation phenomena taking place during the heating stage were studied by thermogravimetry, dilatometry, and mass spectroscopy, using either reducing (H2) or inert (Ar) atmospheres. The results show how the difference in chemical activity between base iron powder and master alloy causes the so called "internal-getter" effect, by which the reduction of less stable iron oxides leads to oxidation of the elements with higher affinity for oxygen. This effect can be somehow minimized when sintering in H2, since the iron oxides are reduced at lower temperatures at which the reactivity of the elements in the master alloy is lower. However, H2 concentration in the processing atmosphere needs to be carefully adapted to the specific composition of the materials being processed in order to minimize decarburization by methane formation during sintering.Höganäs AB Sweden, financial support provided through the Höganäs Chair IVPublicad

    Rate and duration of hospitalisation for acute pulmonary embolism in the real-world clinical practice of different countries : Analysis from the RIETE registry

    Get PDF
    publishersversionPeer reviewe

    Myalgic encephalomyelitis/chronic fatigue syndrome and encephalomyelitis disseminata/multiple sclerosis show remarkable levels of similarity in phenomenology and neuroimmune characteristics

    Full text link

    Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

    Full text link
    The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality
    corecore