946 research outputs found

    ExpresiĂłn de factor tisular, trombomodulina y PAI-1 en placentas de pacientes con restricciĂłn de crecimiento intrauterino o preeclampsia

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    La preeclampsia y la Restricción de crecimiento intrauterino (RCIU) son dos complicaciones de embarazo con un alto componente en la morbilidad y mortalidad perinatal. Se ha propuesto que una alteración en la hemostasis placentaria podría estar involucrada con la fisiopatología de estas entidades. El objetivo de este estudio fue evaluar la alteración en la coagulación a nivel de placenta en embarazos que cursaron con preeclampsia y RCIU. Se obtuvieron placentas de embarazos con RCIU idiopático y preeclampsia y de controles. Se realizó análisis de la expresión de RNAm por PCR en tiempo real de factor tisular, trombomodulina y PAI-1 en placenta. Adicionalmente se evaluó la expresión de hPL en el plasma de gestantes. En los resultados se encontró aumento en la expresión de factor tisular (p=0,0105), de trombomodulina (p=0,0140) en las placentas con preeclampsia, así como aumento de la razón factor tisular/trombomodulina en preeclampsia (p=0,001) y en RCIU (p=0,0411). Adicionalmente fue posible extraer y amplificar RNAm de origen fetoplacentario en el plasma de gestantes, sin embargo la diferencia entre casos y controles no fue significativa. En conclusión existe una alteración de algunos mecanismos hemostáticos locales a nivel de la placenta en embarazos que cursan con preeclampsia o RCIU.Pre-eclampsia and intrauterine growth restrictions (IUGR) are two complications of pregnancy with a high component of perinatal morbidity and mortality. It is proposed that an alteration in placental homeostasis may be involved in the pathophysiology of these entities. The aim of this study was to evaluate the alteration in placental coagulation in pregnancies with preeclampsia and IUGR. It obtained placentas of pregnancies with idiopathic IUGR or preeclampsia and controls. It carried out analysis of the mRNA expression by real-time PCR of tissue factor, thrombomodulin and PAI-1 in placenta. Additionally we evaluated the expression of hPL in plasma of pregnant women. It found increased expression of tissue factor (p = 0.0105), thrombomodulin (p = 0.0140) in preeclamptic placentas, as well as increased tissue factor reason / thrombomodulin level in preeclampsia (p = 0.001) and in IUGR (p = 0.0411). Additionally it was possible to extract and amplify mRNA of fetoplacental origin in plasma of pregnant women; however, the difference between cases and controls was not significant. In conclusion there is an alteration of local hemostatic mechanisms at the level of placenta in pregnancies that occur with preeclampsia or IUGR.MagĂ­ster en Ciencias BiolĂłgicasMaestrĂ­

    Molecular findings of colombian patients with type VI mucopolysaccharidosis (Maroteaux-Lamy syndrome)

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    Q483-89Introduction: Maroteaux–Lamy syndrome, or mucopolysaccharidosis (MPS) type VI, is an autosomal recessive lysosomal storage disease caused by a deficient activity of the enzyme arylsulfatase B (ARSB), required to degrade dermatan sulfate. The onset and progression of the disease vary, producing a spectrum of clinical presentation. So far, 133 mutations have been reported. The aim of this study is to determine the mutations in the ARSB gene that are responsible for this disease in Colombian patients. Results: Fourteen patients with clinical manifestations and biochemical diagnosis of MPS VI were studied, including two siblings. The 8 exons of the gene were directly sequenced from patients' DNA, and 14 mutations were found. 57% of these mutations had not been previously reported (p.H111P, p.C121R, p.G446S, p.*534W, p.S334I, p.H147P, c.900TNG, and c.1531_1553del) and 43% had been previously reported (p.G144R, p.W322*, p.G302R, p.C447F, p.L128del, and c.1143-1GNC). Of the previously reported mutations, 80% have been associated with severe phenotypes and 20% with intermediate-severe phenotypes. Bioinformatic predictions indicate that the new mutations reported in this paper are also highly deleterious. Conclusions: Most of the Colombian patients in this study had private mutations

    MYT1 role in the microtia-craniofacial microsomia spectrum

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    Q2Background: Craniofacial microsomia (CFM), also known as the oculo-auriculovertebral spectrum, comprises a variable phenotype with the most common features including microtia and mandibular hypoplasia on one or both sides, in addition to lateral oral clefts, epibulbar dermoids, cardiac, vertebral, and renal abnormalities. The etiology of CFM is largely unknown. The MYT1 gene has been reported as a candidate based in mutations found in three unrelated individuals. Additional patients with mutations in this gene are required to establish its causality. We present two individuals with CFM that have rare variants in MYT1 contributing to better understand the genotype and phenotype associated with mutations in this gene. Methods/Results: We conducted genetic analysis using whole-exome and -genome sequencing in 128 trios with CFM. Two novel MYT1 mutations were identified in two participants. Sanger sequencing was used to confirm these mutations. Conclusion: We identified two additional individuals with CFM who carry rare variants in MYT1, further supporting the presumptive role of this gene in the CFM spectrum.N/

    Search for dark photons in Higgs boson production via vector boson fusion in proton-proton collisions at √s = 13 TeV

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    A search is presented for a Higgs boson that is produced via vector boson fusion and that decays to an undetected particle and an isolated photon. The search is performed by the CMS collaboration at the LHC, using a data set corresponding to an integrated luminosity of 130 fb−1, recorded at a center-of-mass energy of 13 TeV in 2016–2018. No significant excess of events above the expectation from the standard model background is found. The results are interpreted in the context of a theoretical model in which the undetected particle is a massless dark photon. An upper limit is set on the product of the cross section for production via vector boson fusion and the branching fraction for such a Higgs boson decay, as a function of the Higgs boson mass. For a Higgs boson mass of 125 GeV, assuming the standard model production rates, the observed (expected) 95% confidence level upper limit on the branching fraction is 3.5 (2.8)%. This is the first search for such decays in the vector boson fusion channel. Combination with a previous search for Higgs bosons produced in association with a Z boson results in an observed (expected) upper limit on the branching fraction of 2.9 (2.1)% at 95% confidence level

    Search for new particles in events with energetic jets and large missing transverse momentum in proton-proton collisions at root s=13 TeV

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    A search is presented for new particles produced at the LHC in proton-proton collisions at root s = 13 TeV, using events with energetic jets and large missing transverse momentum. The analysis is based on a data sample corresponding to an integrated luminosity of 101 fb(-1), collected in 2017-2018 with the CMS detector. Machine learning techniques are used to define separate categories for events with narrow jets from initial-state radiation and events with large-radius jets consistent with a hadronic decay of a W or Z boson. A statistical combination is made with an earlier search based on a data sample of 36 fb(-1), collected in 2016. No significant excess of events is observed with respect to the standard model background expectation determined from control samples in data. The results are interpreted in terms of limits on the branching fraction of an invisible decay of the Higgs boson, as well as constraints on simplified models of dark matter, on first-generation scalar leptoquarks decaying to quarks and neutrinos, and on models with large extra dimensions. Several of the new limits, specifically for spin-1 dark matter mediators, pseudoscalar mediators, colored mediators, and leptoquarks, are the most restrictive to date.Peer reviewe

    Probing effective field theory operators in the associated production of top quarks with a Z boson in multilepton final states at root s=13 TeV

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    Measurement of the top quark Yukawa coupling from t(t)over-bar kinematic distributions in the dilepton final state in proton-proton collisions at root s=13 TeV

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    Search for top squark pair production using dilepton final states in pp collision data collected at root s=13TeV

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    A search is presented for supersymmetric partners of the top quark (top squarks) in final states with two oppositely charged leptons (electrons or muons), jets identified as originating from bquarks, and missing transverse momentum. The search uses data from proton-proton collisions at root s = 13 TeV collected with the CMS detector, corresponding to an integrated luminosity of 137 fb(-1). Hypothetical signal events are efficiently separated from the dominant top quark pair production background with requirements on the significance of the missing transverse momentum and on transverse mass variables. No significant deviation is observed from the expected background. Exclusion limits are set in the context of simplified supersymmetric models with pair-produced lightest top squarks. For top squarks decaying exclusively to a top quark and a lightest neutralino, lower limits are placed at 95% confidence level on the masses of the top squark and the neutralino up to 925 and 450 GeV, respectively. If the decay proceeds via an intermediate chargino, the corresponding lower limits on the mass of the lightest top squark are set up to 850 GeV for neutralino masses below 420 GeV. For top squarks undergoing a cascade decay through charginos and sleptons, the mass limits reach up to 1.4 TeV and 900 GeV respectively for the top squark and the lightest neutralino.Peer reviewe

    Combined searches for the production of supersymmetric top quark partners in proton-proton collisions at root s=13 TeV

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    A combination of searches for top squark pair production using proton-proton collision data at a center-of-mass energy of 13 TeV at the CERN LHC, corresponding to an integrated luminosity of 137 fb(-1) collected by the CMS experiment, is presented. Signatures with at least 2 jets and large missing transverse momentum are categorized into events with 0, 1, or 2 leptons. New results for regions of parameter space where the kinematical properties of top squark pair production and top quark pair production are very similar are presented. Depending on themodel, the combined result excludes a top squarkmass up to 1325 GeV for amassless neutralino, and a neutralinomass up to 700 GeV for a top squarkmass of 1150 GeV. Top squarks with masses from 145 to 295 GeV, for neutralino masses from 0 to 100 GeV, with a mass difference between the top squark and the neutralino in a window of 30 GeV around the mass of the top quark, are excluded for the first time with CMS data. The results of theses searches are also interpreted in an alternative signal model of dark matter production via a spin-0 mediator in association with a top quark pair. Upper limits are set on the cross section for mediator particle masses of up to 420 GeV

    Search for long-lived particles decaying to jets with displaced vertices in proton-proton collisions at root s=13 Te V

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    A search is presented for long-lived particles produced in pairs in proton-proton collisions at the LHC operating at a center-of-mass energy of 13 TeV. The data were collected with the CMS detector during the period from 2015 through 2018, and correspond to a total integrated luminosity of 140 fb(-1). This search targets pairs of long-lived particles with mean proper decay lengths between 0.1 and 100 mm, each of which decays into at least two quarks that hadronize to jets, resulting in a final state with two displaced vertices. No significant excess of events with two displaced vertices is observed. In the context of R-parity violating supersymmetry models, the pair production of long-lived neutralinos, gluinos, and top squarks is excluded at 95% confidence level for cross sections larger than 0.08 fb, masses between 800 and 3000 GeV, and mean proper decay lengths between 1 and 25 mm.Peer reviewe
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