3,059 research outputs found

    Do the mutations of C1GALT1C1 gene play important roles in the genetic susceptibility to Chinese IgA nephropathy?

    Get PDF
    Background: The deficiency of beta 1,3 galactose in hinge region of IgA1 molecule played a pivotal role in pathogenesis of IgA nephropathy (IgAN). Cosmc, encoded by C1GALT1C1 gene, was indispensable to beta 1,3 galactosylation of IgA1. We designed a serial study to investigate the relationship between the mutations of C1GALT1C1 gene and the genetic susceptibility to IgAN. Methods: Nine hundred and thirty-eight subjects, including 661 patients with IgAN and 277 healthy controls were enrolled in the study. Firstly, single nucleotide polymorphisms (SNPs) in the promoter region of C1GALT1C1 gene were screened. Then the c.-347-190G> A was analyzed by PCR-restriction fragment length polymorphism (PCR-RFLP) for further case-control association analysis. Secondly the somatic mutations of DNAs from peripheral blood B lymphocytes were detected in 15 patients and 7 normal controls. Results: No significant association was observed between the different alleles or genotypes of c.347-190G>A and IgAN. The patients with different genotypes of C1GALT1C1 gene did not significantly associate with clinical manifestations, including hematuria, proteinuria, and serum creatinine of patients with IgAN. There was no somatic mutation detected in total 202 clones of 22 individuals. Conclusion: The c.-347-190G>A polymorphism and the somatic mutation of encoding region of C1GALT1C1 gene were not significantly related to the genetic susceptibility to IgAN in Northern Chinese population.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000271285100001&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Genetics & HereditySCI(E)PubMed1ARTICLE1011

    Damage Detection in Tensegrity using Interacting Particle-Ensemble Kalman Filter

    Get PDF
    The 10th EWSHM, originally scheduled for the first week of July 2020, is planned to be held the first week of July 2022 in Palermo.International audienceTensegrity structures form a special class of truss with dedicated cables and bars, that take tension and compression, respectively. To ensure equilibrium, the tensegrity members are required to be prestressed. Over prolonged usage, the cables may lose their prestress while bars may buckle, affecting the structural stiffness as well as its dynamic properties. The stiffness of tensegrities also vary with the load even in the absence of damage. This can potentially mask the effect of damage leading to a false impression of tensegrity health. This poses a major challenge in tensegrity health monitoring especially when the load is stochastic and unknown. Present study develops a vibration based output-only time-domain approach for monitoring the health of any tensegrity in the presence of uncertainties due to ambient force and measurement noise. An Interacting Particle Ensemble Kalman Filter (IPEnKF) has been used that can efficiently monitor tensegrity health from contaminated response data. IPEnKF combines a bank of Ensemble Kalman Filters to estimate response states while running within a Particle Filter envelop that estimates a set of location based health parameters. Further to make damage detection cheaper, strain responses are used as measurements. The efficiency of the proposed methodology has been demonstrated using numerical experiments performed on a simplex tensegrity

    Cystathionine beta-synthase mutants exhibit changes in protein unfolding: conformational analysis of misfolded variants in crude cell extracts

    Get PDF
    Protein misfolding has been proposed to be a common pathogenic mechanism in many inborn errors of metabolism including cystathionine β-synthase (CBS) deficiency. In this work, we describe the structural properties of nine CBS mutants that represent a common molecular pathology in the CBS gene. Using thermolysin in two proteolytic techniques, we examined conformation of these mutants directly in crude cell extracts after expression in E. coli. Proteolysis with thermolysin under native conditions appeared to be a useful technique even for very unstable mutant proteins, whereas pulse proteolysis in a urea gradient had limited values for the study of the majority of CBS mutants due to their instability. Mutants in the active core had either slightly increased unfolding (p.A114V, p.E302K and p.G307S) or extensive unfolding with decreased stability (p.H65R, p.T191M, p.I278T and p.R369C). The extent of the unfolding inversely correlated with the previously determined degree of tetrameric assembly and with the catalytic activity. In contrast, mutants bearing aminoacid substitutions in the C-terminal regulatory domain (p.R439Q and p.D444N) had increased global stability with decreased flexibility. This study shows that proteolytic techniques can reveal conformational abnormalities even for CBS mutants that have activity and/or a degree of assembly similar to the wild-type enzyme. We present here a methodological strategy that may be used in cell lysates to evaluate properties of proteins that tend to misfold and aggregate and that may be important for conformational studies of disease-causing mutations in the field of inborn errors of metabolism

    Two naturally occurring insulin receptor tyrosine kinase domain mutants provide evidence that phosphoinositide 3-kinase activation alone is not sufficient for the mediation of insulin's metabolic and mitogenic effects

    Get PDF
    We have recently reported (1) that two naturally occurring mutants of the insulin receptor tyrosine kinase domain, Arg-1174 --> Gln and Pro-1178 --> Leu (Gln-1174 and Leu1178, respectively), both found in patients with inherited severe insulin resistance, markedly impaired receptor tyrosine autophosphorylation, with both mutant receptors; being unable to mediate the stimulation of glycogen synthesis or mitogenesis by insulin when expressed hh Chinese hamster ovary cells, However, these mutations did not fully prevent IRS-1 phosphorylation in response to insulin in these cells, suggesting that IRS-1 alone may not be sufficient to mediate insulin's metabolic and mitogenic effects, In the present study, we have demonstrated that these mutations also impair the ability of the insulin receptor to activate the transcription factor Elk-1 and promote GLUT4 translocation to the plasma membrane, Although at law concentrations of insulin, the mutant receptors were impaired in their ability to stimulate the tyrosine phosphorylation of IRS-1, at higher insulin concentrations we confirmed that the cells expressing the mutant receptors showed significantly increased tyrosine phosphorylation of IRS-1 compared with parental nontransfected cells, In addition, at comparable insulin concentrations, the association of the p85 alpha subunit of phosphoinositide 3-kinase (PI3-kinase) with IRS-1 and the enzymatic activity of IRS-1-associated PI3-kinase were significantly enhanced in cells expressing the mutant receptors, in contrast, no significant stimulation of the tyrosine phosphorylation of Shc, GTP loading of Ras, or mitogen-activated protein kinase phosphorylation was seen in cell lines expressing these mutant receptors. Thus, no activation of any measurable mitogenic or metabolic response was detectable, despite significant insulin-induced phosphorylation of IRS-1 and its association with PI3-kinase in cells stably expressing the mutant insulin receptors, These findings suggest that PI3-kinase activation alone may be insufficient to mediate a wide range of the metabolic and mitogenic effects of insulin, Additionally, the data provide support for the notion that insulin activation of Ras is more closely linked with Shc, and not IRS-1, phosphorylation

    Autoimmune and autoinflammatory mechanisms in uveitis

    Get PDF
    The eye, as currently viewed, is neither immunologically ignorant nor sequestered from the systemic environment. The eye utilises distinct immunoregulatory mechanisms to preserve tissue and cellular function in the face of immune-mediated insult; clinically, inflammation following such an insult is termed uveitis. The intra-ocular inflammation in uveitis may be clinically obvious as a result of infection (e.g. toxoplasma, herpes), but in the main infection, if any, remains covert. We now recognise that healthy tissues including the retina have regulatory mechanisms imparted by control of myeloid cells through receptors (e.g. CD200R) and soluble inhibitory factors (e.g. alpha-MSH), regulation of the blood retinal barrier, and active immune surveillance. Once homoeostasis has been disrupted and inflammation ensues, the mechanisms to regulate inflammation, including T cell apoptosis, generation of Treg cells, and myeloid cell suppression in situ, are less successful. Why inflammation becomes persistent remains unknown, but extrapolating from animal models, possibilities include differential trafficking of T cells from the retina, residency of CD8(+) T cells, and alterations of myeloid cell phenotype and function. Translating lessons learned from animal models to humans has been helped by system biology approaches and informatics, which suggest that diseased animals and people share similar changes in T cell phenotypes and monocyte function to date. Together the data infer a possible cryptic infectious drive in uveitis that unlocks and drives persistent autoimmune responses, or promotes further innate immune responses. Thus there may be many mechanisms in common with those observed in autoinflammatory disorders

    Conflict in the Indian Kashmir Valley II: psychosocial impact

    Get PDF
    ABSTRACT: BACKGROUND: India and Pakistan have disputed ownership of the Kashmir Valley region for many years, resulting in high level of exposure to violence among the civilian population of Kashmir (India). A survey was done as part of routine programme evaluation to assess confrontation with violence and its consequences on mental health, health service usage, and socio-economic functioning. METHODS: We undertook a two-stage cluster household survey in two districts of Kashmir (India) using questionnaires adapted from other conflict areas. Analysis was stratified for gender. RESULTS: Over one-third of respondents (n=510) were found to have symptoms of psychological distress (33.3%, CI: 28.3-38.4); women scored significantly higher (OR 2.5; CI: 1.7-3.6). A third of respondents had contemplated suicide (33.3%, CI: 28.3-38.4). Feelings of insecurity were associated with higher levels of psychological distress for both genders (males: OR 2.4, CI: 1.3-4.4; females: OR 1.9, CI: 1.1-3.3). Among males, violation of modesty, (OR 3.3, CI: 1.6-6.8), forced displacement, (OR 3.5, CI: 1.7-7.1), and physical disability resulting from violence (OR 2.7, CI: 1.2-5.9) were associated with greater levels of psychological distress; for women, risk factors for psychological distress included dependency on others for daily living (OR 2.4, CI: 1.3-4.8), the witnessing of killing (OR 1.9, CI: 1.1-3.4), and torture (OR 2.1, CI: 1.2-3.7). Self-rated poor health (male: OR 4.4, CI: 2.4-8.1; female: OR 3.4, CI: 2.0-5.8) and being unable to work (male: OR 6.7, CI: 3.5-13.0; female: OR 2.6, CI: 1.5-4.4) were associated with mental distress. CONCLUSIONS: The ongoing conflict exacts a huge toll on the communities' mental well-being. We found high levels of psychological distress that impacts on daily life and places a burden on the health system. Ongoing feelings of personal vulnerability (not feeling safe) were associated with high levels of psychological distress. Community mental health programmes should be considered as a way reduce the pressure on the health system and improve socio-economic functioning of those suffering from mental health problems
    corecore