986 resultados para factor XI deficiency
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Poster presented at the International Society on Thrombosis and Haemostasis 2015 Congress, 20-25 June 2015, Toronto.
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Placenta growth factor (PlGF) deficient mice are fertile at a Mendelian ratio. Interestingly, low maternal plasma levels of PlGF are strongly associated with early onset of preeclampsia, a pregnancy hypertensive disorder characterised by high blood pressure, proteinuria and fetal growth restriction. PlGF is increasingly being recognised as an early diagnostic biomarker, but the physiological importance of PlGF in the pathogenesis of preeclampsia is unknown. We investigated whether the decreased levels of PlGF in pregnancy exacerbate the fetal growth restriction associated with preeclampsia in the presence of high sFlt-1 and the potential of hydrogen sulphide to ameliorate these effects. Pregnant PlGF−/− mice were injected with adenovirus encoding sFlt-1 (Ad-sFlt-1) at 1 × 109 pfu/ml at E10.5 and mean arterial blood pressure (MAP), biochemical and histological analysis of maternal kidney, placenta and embryos were assessed at the end of pregnancy. Ad-sFlt-1 significantly increased MAP and induced severe glomerular endotheliosis in PlGF−/− mice compared to wild-type animals. Soluble Flt-1 also significantly elevated albumin–creatinine ratio and increased levels of urinary kidney injury molecule-1, a marker for proximal tubule injury. Furthermore, sFlt-1 over expression increased fetal resorption rate in the PlGF−/− mice and promoted abnormal placental vascularisation. To determine whether placental PlGF is critical for preventing fetal growth restriction associated with preeclampsia, we generated haploinsufficient PlGF+/− placentas and embryos in dams and exposed to high sFlt-1 environment. These mothers showed reduced fetal resorption, gestational hypertension and proteinuria when compared to pregnant PlGF−/− mice. Furthermore, treatment with hydrogen sulphide-releasing agent, GYY4137, significantly reduced resorption, hypertension and proteinuria observed in Ad-sFlt-1 treated pregnant PlGF−/− mice. Our study shows that placental PlGF is a critical protective factor against the damaging effects of high sFlt-1 associated with preeclampsia and activation of the hydrogen sulphide pathway may rescue preeclampsia phenotypes even under low PlGF environment.
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INTRODUCTION: Low circulating levels of placenta growth factor (PlGF) is strongly associated with the onset of preeclampsia, a maternal hypertensive disorder characterized by high blood pressure and proteinuria after 20 weeks of gestation. Although, PlGF-deficient mice are born healthy and fertile at a Mendelian ratio, the physiological importance of PlGF in the pathogenesis of preeclampsia is unclear. We hypothesised that decreased levels of PlGF in pregnancy exacerbates the fetal growth restriction associated with preeclampsia in the presence of high sFlt-1. METHODS: Pregnant PlGF-/- mice were injected with adenovirus encoding sFlt-1 (Ad-sFlt-1) at high (i) 1.5x109 pfu/ml and low (ii) 0.5x109 pfu/ml doses. Mean arterial blood pressure (MBP), biochemical and histological assessments of maternal kidney, placenta and embryos were performed. RESULTS: Ad-sFlt-1 significantly increased MBP and induced severe glomerular endotheliosis in PlGF-/- mice at E10.5 gestation compared to wild-type animals. High sFlt-1 also significantly elevated albumincreatinine ratio and increased levels of urinary kidney injury molecule-1, a marker for proximal tubule injury.At a high dose of sFlt-1, there was complete fetal resorption in the pregnant PlGF-/- mice, and even the lower dose of sFlt-1 induced severe fetal resorption and abnormal placental vascularization. Hydrogen sulphide-releasing agent, GYY4137, significantly reduced resorption, hypertension and proteinuria in Ad-sFlt-1 treated pregnant PlGF-/- mice. To determine if placental PlGF is critical for preventing fetal growth restriction associated with preeclampsia, we generated haploinsufficient PlGF+/- placentas and embryos were generated in wild-time dams and exposed to high sFlt-1 environment. This resulted in reduced fetal resorption, gestational hypertension and proteinuria when compared to pregnant PlGF-/- mice. CONCLUSIONS: Placental PlGF is a critical protective factor against the damaging effects of high sFlt-1 in preeclampsia and the hydrogen sulphide pathway may rescue preeclampsia phenotypes.
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A deficiência do fator XI, também conhecida como hemofilia C, é uma doença hematológica hereditária rara, que se manifesta clinicamente com hemorragia persistente após cirurgias, traumas, menorragias e extrações dentárias. Neste artigo, relatou-se a correção endovascular de um paciente com aneurisma de aorta e de artéria ilíaca comum esquerda em um paciente portador de deficiência major do fator XI (atividade do fator XI inferior a 20%). O procedimento foi realizado com sucesso, com o manuseio do distúrbio da coagulação por meio da infusão de plasma fresco no pré-operatório imediato e no pós-operatório, e controle laboratorial da coagulação do paciente.
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We identified a 4-year-old Brazilian boy from a family of Japanese descent and history of consanguinity, who suffered from severe recurrent pneumonia. He carries factor H (FH) deficiency associated with reduced levels of component C9 and low serum levels of C3 and factor B. His mother also presented low levels of these proteins and factor I, while his father and sister had only lower levels of FH. Western blot assays confirmed the complete absence of FH and FHL-1 polypeptides in this patient. Sequencing of the proband`s FH cDNA revealed a homozygous G453A substitution, encoding an Arg(127)His change. His mother, father and sister are heterozygous for this substitution. Despite the absence of FH in the plasma, this protein was detected in the patient`s fibroblasts, suggesting that Arg(127) may be important for FH secretion. Low concentrations of C9 were detected in the proband serum but no mutations in the patient`s C9 gene or promoter have been identified, suggesting that this is a consequence of uncontrolled complement activation and high C9 consumption.
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Severe hereditary coagulation factor XIII deficiency is a rare homozygous bleeding disorder affecting one person in every two million individuals. In contrast, heterozygous factor XIII deficiency is more common, but usually not associated with severe hemorrhage such as intracranial bleeding or hemarthrosis. In most cases, the disease is caused by F13A gene mutations. Causative mutations associated with the F13B gene are rarer.
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The vertical uplift resistance of two interfering rigid rough strip anchors embedded horizontally in sand at shallow depths has been examined. The analysis is performed by using an upper bound theorem o limit analysis in combination with finite elements and linear programming. It is specified that both the anchors are loaded to failure simultaneously at the same magnitude of the failure load. For different clear spacing (S) between the anchors, the magnitude of the efficiency factor (xi(gamma)) is determined. On account of interference, the magnitude of xi(gamma) is found to reduce continuously with a decrease in the spacing between the anchors. The results from the numerical analysis were found to compare reasonably well with the available theoretical data from the literature.
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The horizontal pullout capacity of a group of two vertical strip anchors placed along the same vertical plane in sand has been determined by using the upper bound finite elements limit analysis. The variation of the efficiency factor (xi (gamma) ) with changes in clear spacing (S) between the anchors has been established to evaluate the total group failure load for different values of (i) embedment ratio (H/B), (ii) soil internal friction angle (phi), and (iii) anchor-soil interface friction angle (delta). The total group failure load, for a given H/B, becomes always maximum corresponding to a certain optimal spacing (S-opt). The value of S-opt/B was found to lie in a range of 0.5-1.4. The maximum magnitude of xi (gamma) increases generally with increases in H/B, phi and delta.
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This paper reports first observations of transition in recirculation pattern from an open-bubble type axisymmetric vortex breakdown to partially open bubble mode through an intermediate, critical regime of conical sheet formation in an unconfined, co-axial isothermal swirling flow. This time-mean transition is studied for two distinct flow modes which are characterized based on the modified Rossby number (Ro(m)), i.e., Ro(m) <= 1 and Ro(m) > 1. Flow modes with Ro(m) <= 1 are observed to first undergo cone-type breakdown and then to partially open bubble state as the geometric swirl number (S-G) is increased by similar to 20% and similar to 40%, respectively, from the baseline open-bubble state. However, the flow modes with Ro(m) > 1 fail to undergo such sequential transition. This distinct behavior is explained based on the physical significance associated with Ro(m) and the swirl momentum factor (xi). In essence, xi represents the ratio of angular momentum distributed across the flow structure to that distributed from central axis to the edge of the vortex core. It is observed that xi increases by similar to 100% in the critical swirl number band where conical breakdown occurs as compared to its magnitude in the S-G regime where open bubble state is seen. This results from the fact that flow modes with Ro(m) <= 1 are dominated by radial pressure gradient due to swirl/rotational effect when compared to radial pressure deficit arising from entrainment (due to the presence of co-stream). Consequently, the imparted swirl tends to penetrate easily towards the central axis causing it to spread laterally and finally undergo conical sheet breakdown. However, the flow modes with Ro(m) > 1 are dominated by pressure deficit due to entrainment effect. This blocks the radial inward penetration of imparted angular momentum thus preventing the lateral spread of these flow modes. As such these structures fail to undergo cone mode of vortex breakdown which is substantiated by a mere 30%-40% rise in xi in the critical swirl number range. (C) 2014 AIP Publishing LLC.
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The vertical uplift resistance of interfering pipelines buried in sands has been computed using the lower-bound limit analysis in conjunction with finite elements and nonlinear optimization. The soil mass is assumed to follow the Mohr-Coulomb failure criterion and an associated flow rule. It is specified that all the pipes fail simultaneously at the same magnitude of the failure load. For different clear spacing (S) between the pipes, the magnitude of the efficiency factor (xi(gamma)) is determined. Because of pipes' interference, with a reduction in the spacing between the pipelines, the magnitude of xi(gamma) is found to decrease continuously. The results were found to compare quite well with the available data from literature for horizontal strip anchors. (C) 2015 American Society of Civil Engineers.
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AZEVEDO, George Dantas de et al. Procoagulant state after raloxifene therapy in postmenopausal women. Fertility and Sterility, Estados Unidos, v.84, n.6, p.1680-1684, 2005
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Silicosis, a common type of pneumoconiosis, is an occupational lung disease caused by inhalation of silica dust often with mining activity and thus reaches the miners. The fine and ultrafine silica particles deposited in the alveolar epithelium may lead to the development of progressive massive fibrosis. An increased reactive oxygen species (ROS) production has been proposed to explain the mechanism for induction of pulmonary fibrosis in silicosis. In this situation, alveolar macrophages are activated to phagocytes silica particles deposited in the alveoli. The activated macrophages secrete large amounts of ROS that in turn induce synthesis of fibrotic factors. In addition, the activity of antioxidant enzymes is impaired, which results in increased lipid peroxidation, as well as generating a local inflammatory process. Diffuse pulmonary fibrosis progresses with interstitial collagen deposition. Interstitial collagen overlies small pulmonary arteries and arterioles and thus it is associated with pulmonary hypertension in pulmonary fibrotic diseases. In addition, cytokines and silica particles passing through the respiratory membrane can reach the bloodstream. In this context, the increase in the generation of ROS in the circulation may lead to a reduction in the bioavailability of nitric oxide, an important endothelium-derived relaxing factor. A deficiency in the nitric oxide bioavailability can result in vascular endothelial dysfunction. Moreover, pro-inflammatory cytokines could contribute to the impairment of endothelial function. In the airways, pro-inflammatory cytokines can reduce the smooth muscle responsiveness to β- adrenergic agonists as isoproterenol. Thus, the aim of this study was to evaluate the effect of silica dust instillation in the function of the pulmonary artery, aorta and trachea of rats with acute silicosis. For this purpose, male Wistar rats were anesthetized... (Complete abstract click electronic access below)
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Auriculo-condylar syndrome (ACS) is characterized by typical ears malformation (so-called "question mark" ears), prominent cheeks, microstomia, and abnormality of the temporomandibular joint and condyle of the mandible. In this report we describe a new simplex case and a previously unreported family with affected individuals in three generations documenting clinical variability. Linkage study for markers located in candidate region for ACS1 (1p21.1-q23.3) was excluded in our familial case, reinforcing the hypothesis of genetic heterogeneity for this condition. A review of the literature focusing diagnostic criteria and features of ACS was performed. (C) 2011 Wiley Periodicals, Inc.
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BACKGROUND: Splenic involvement in amyloidosis is rather frequent (5-10%). An atraumatic rupture of the affected spleen is however an extremely rare event. We report on a patient with undiagnosed amyloidosis who underwent emergency splenectomy for atraumatic splenic rupture. METHODS: Review of the literature and identification of 31 patients, including our own case report, with atraumatic splenic rupture in amyloidosis. Analysis of the clinical presentation, the surgical management, the nomenclature and definition of predisposing factors of splenic rupture. RESULTS: We identified 15 women and 16 men (mean age 53.3 +/- 12.4 years; median 52, range: 27-82 years) with an atraumatic splenic rupture. Easy skin bruisability and factor X deficiency were detected in four (13%) and five patients (16%), respectively. The diagnosis of splenic rupture was made either by computed tomography (n = 12), ultrasound (n = 5), exploratory laparotomy (n = 9) or autopsy (n = 4). All patients underwent surgery (n = 27) or autopsy (n = 4). Amyloidosis was previously diagnosed in nine patients (29%). In the remaining 22 patients (71%), the atraumatic splenic rupture represented the initial manifestation of amyloidosis. Twenty-five patients (81%) suffered from primary (AL) and four patients (13%) from secondary amyloidosis (AA). In two patients, the type of amyloidosis was not specified. A moderate splenomegaly was a common feature (68%) and the characteristic intraoperative finding was an extended subcapsular hematoma with a limited parenchymal laceration (65%). In five patients with known amyloidosis, the atraumatic splenic rupture was closely associated with autologous stem-cell transplantation (ASCT) (16%). Three patients were suffering from multiple myeloma (10%). A biopsy-proven amyloidotic liver involvement was present in 14 patients (45%), which lead to atraumatic liver rupture in two patients. The splenic rupture related 30-day mortality was 26% (8/31). CONCLUSIONS: Atraumatic splenic rupture in amyloidosis is associated with a high 30-day mortality. It occurs predominantly in patients with previously undiagnosed amyloidosis. A moderate splenomegaly, coagulation abnormalities (easy skin bruisability, factor X deficiency) and treatment of amyloidosis with ASCT are considered predisposing factors for an atraumatic splenic rupture.
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AZEVEDO, George Dantas de et al. Procoagulant state after raloxifene therapy in postmenopausal women. Fertility and Sterility, Estados Unidos, v.84, n.6, p.1680-1684, 2005