1,257 research outputs found

    A sensitive technique to determine influence of body composition on surface EMG

    Get PDF
    Exposition of the problem -- Physiology of skeletal muscle -- Action potentiel and its propagation -- Muscular contraction -- Motor units -- Electromyography -- Detection of extracellular action potentials -- Electromyograms -- Detection of electromyograms -- Analysis of the electromyogram -- Single fibers models -- Multi-fiber models -- SEMG generation models -- Spectral parameters and conduction velocity -- Electrode location -- Selection and control of experimental parameters -- Optimization of the SEMG signal -- Experimental parameters -- Choice of muscle -- Electrode location and orientation -- Volume conductive media -- Muscle length -- Level of contraction -- Validation of the experimental parameters -- Selection of subjects -- Experimental equipment -- Stimulator -- Control of the stimulator -- Electrodes -- Experimental chair -- Data acquisition -- EMG acquisition interface -- Recording evoked action potentials -- Recording voluntary contraction -- Experimental protocol -- Installation for recording -- Mapping innervation points -- Locating optimal recording site -- Data processing -- Processing of evoked potentials -- Processing of voluntary contraction -- Analysis of electrode selectivity -- Analysis of conductive media -- Analysis of electrode orientation -- Analysis of electrode orientation under voluntary contraction

    A four dimensional spatio-temporal EMG mapping technique for study of the neuro-musculo-skeletal system

    Full text link
    Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal

    Survival of patients receiving a liver transplant for hepatocellular carcinoma, and risk of tumor recurrence

    Get PDF
    Objective: the goal of this research has been to evaluate the survival, in long and short term, of the patient receiving liver transplant for hepatocellular carcinoma (HCC), the risk of posttransplant tumor relapse and factors related to this complication. Design: retrospective study of a consecutive series of patients having had liver transplant for HCC. Patients and methodology: transplant patients for HCC from 1989 to November 2003. Patients were selected due to general limitations of nodule size and quantity, which were subsequently published as Milan criteria. Also, criteria agreed in the Conference of Barcelona were followed in the pre-transplant diagnosis. Results: the survival of this 81 patients group was of the 80, 61 and 52% for 1, 5 and 10 years respectively. In the 32% of the cases the HCC was an incidental finding in the explant. In the 12.3%, the tumor relapse was verified. The multivariate research identified the size of the nodule (OR = 1,7944) (IC 95% = 1,1332-2,8413) and the vascular invasion (OR = 6,6346) (IC 95% = 1,4624-30,1003) as risk factors of relapse. Conclusions: the liver transplant in selected patients with HCC has good results in medium and long term. The risk of post-transplant tumor relapse becomes notably reduced and is associated with the size of the nodule and the microscopic vascular invasion

    Clonal hematopoiesis is not prevalent in Hutchinson-Gilford progeria syndrome.

    Get PDF
    Clonal hematopoiesis of indeterminate potential (CHIP), defined as the presence of somatic mutations in cancer-related genes in blood cells in the absence of hematological cancer, has recently emerged as an important risk factor for several age-related conditions, especially cardiovascular disease. CHIP is strongly associated with normal aging, but its role in premature aging syndromes is unknown. Hutchinson-Gilford progeria syndrome (HGPS) is an ultra-rare genetic condition driven by the accumulation of a truncated form of the lamin A protein called progerin. HGPS patients exhibit several features of accelerated aging and typically die from cardiovascular complications in their early teens. Previous studies have shown normal hematological parameters in HGPS patients, except for elevated platelets, and low levels of lamin A expression in hematopoietic cells relative to other cell types in solid tissues, but the prevalence of CHIP in HGPS remains unexplored. To investigate the potential role of CHIP in HGPS, we performed high-sensitivity targeted sequencing of CHIP-related genes in blood DNA samples from a cohort of 47 HGPS patients. As a control, the same sequencing strategy was applied to blood DNA samples from middle-aged and elderly individuals, expected to exhibit a biological age and cardiovascular risk profile similar to HGPS patients. We found that CHIP is not prevalent in HGPS patients, in marked contrast to our observations in individuals who age normally. Thus, our study unveils a major difference between HGPS and normal aging and provides conclusive evidence that CHIP is not frequent in HGPS and, therefore, is unlikely to contribute to the pathophysiology of this accelerated aging syndrome.This work was supported by Fundación “la Caixa” (grant number LCF/PR/HR17/52150007 to VF, and JJF). JJF is supported by a Ramón y Cajal award (RYC2016–20026) from the Spanish Ministerio de Ciencia e Innovación (MICIN)/Agencia Estatal de Investigación (AEI)/10.13039/501100011033 and Fondo Social Europeo “El FSE invierte en tu futuro”. VA’s lab is supported by MICIN/ AEI/10.13039/501100011033 and Fondo Social Europeo “El FSE invierte en tu futuro” (grant number PID2019-108489RBI00), the Progeria Research Foundation (Award PRF 2019–77), and a donation from Asociación Progeria Alexandra Peraut. LBG is supported by The Progeria Research Foundation. MDD is supported by a predoctoral FPI fellowship from the Spanish MICIN/AEI/10.13039/501100011033 and Fondo Social Europeo “El FSE invierte en tu futuro” (PRE2019-087463), and MA-P is supported by a predoctoral FPU contract from the Ministerio de Educación, Cultura y Deporte (FPU18/02913). The CNIC is supported by the MICIN, the Instituto de Salud Carlos III, the Pro-CNIC Foundation, and is a Severo Ochoa Center of Excellence (grant number CEX2020-001041-S funded by MICIN/AEI/10.13039/501100011033).S

    Lack of validation of genetic variants associated with anti-tumor necrosis factor therapy response in rheumatoid arthritis: a genome-wide association study replication and meta-analysis

    Get PDF
    Introduction: In this study, our aim was to elucidate the role of four polymorphisms identified in a prior large genome-wide association study (GWAS) in which the investigators analyzed the responses of patients with rheumatoid arthritis (RA) to treatment with tumor necrosis factor inhibitors (TNFi). The authors of that study reported that the four genetic variants were significantly associated. However, none of the associations reached GWAS significance, and two subsequent studies failed to replicate these associations. Methods: The four polymorphisms (rs12081765, rs1532269, rs17301249 and rs7305646) were genotyped in a total of 634 TNFi-treated RA patients of Spanish Caucasian origin. Four outcomes were evaluated: changes in the Disease Activity Score in 28 joints (DAS28) after 6 and 12 months of treatment and classification according to the European League Against Rheumatism (EULAR) response criteria at the same time points. Association with DAS28 changes was assessed by linear regression using an additive genetic model. Contingency tables of genotype and allele frequencies between EULAR responder and nonresponder patients were compared. In addition, we combined our data with those of previously reported studies in a meta-analysis including 2,998 RA patients. Results: None of the four genetic variants showed an association with response to TNFi in any of the four outcomes analyzed in our Spanish patients. In addition, only rs1532269 yielded a suggestive association (P = 0.0033) with the response to TNFi when available data from previous studies were combined in the meta-analysis. Conclusion: Our data suggest that the rs12081765, rs1532269, rs17301249 and rs7305646 genetic variants do not have a role as genetic predictors of TNFi treatment outcomes

    Toenail zinc as a biomarker: Relationship with sources of environmental exposure and with genetic variability in MCC-Spain study

    Full text link
    Background: Toenails are commonly used as biomarkers of exposure to zinc (Zn), but there is scarce information about their relationship with sources of exposure to Zn. Objectives: To investigate the main determinants of toenail Zn, including selected sources of environmental exposure to Zn and individual genetic variability in Zn metabolism. Methods: We determined toenail Zn by inductively coupled plasma mass spectrometry in 3,448 general popu-lation controls from the MultiCase-Control study MCC-Spain. We assessed dietary and supplement Zn intake using food frequency questionnaires, residential proximity to Zn-emitting industries and residential topsoil Zn levels through interpolation methods. We constructed a polygenic score of genetic variability based on 81 single nucleotide polymorphisms in genes involved in Zn metabolism. Geometric mean ratios of toenail Zn across categories of each determinant were estimated from multivariate linear regression models on log-transformed toenail Zn. Results: Geometric mean toenail Zn was 104.1 mu g/g in men and 100.3 mu g/g in women. Geometric mean toenail Zn levels were 7 % lower (95 % confidence interval 1-13 %) in men older than 69 years and those in the upper tertile of fibre intake, and 9 % higher (3-16 %) in smoking men. Women residing within 3 km from Zn-emitting industries had 4 % higher geometric mean toenail Zn levels (0-9 %). Dietary Zn intake and polygenic score were unrelated to toenail Zn. Overall, the available determinants only explained 9.3 % of toenail Zn variability in men and 4.8 % in women. Discussion: Sociodemographic factors, lifestyle, diet, and environmental exposure explained little of the indi-vidual variability of toenail Zn in the study population. The available genetic variants related to Zn metabolism were not associated with toenail Zn

    Odderon Exchange from Elastic Scattering Differences between pp and pp^{-} Data at 1.96 TeV and from pp Forward Scattering Measurements

    Get PDF
    We describe an analysis comparing the p¯p elastic cross section as measured by the D0 Collaboration at a center-of-mass energy of 1.96 TeV to that in pp collisions as measured by the TOTEM Collaboration at 2.76, 7, 8, and 13 TeV using a model-independent approach. The TOTEM crosssections, extrapolated to a center-of-mass energy of √s=1.96  TeV, are compared with the D0 measurement in the region of the diffractive minimum and the second maximum of the pp cross section. The two data sets disagree at the 3.4σ level and thus provide evidence for the t-channel exchange of a colorless, C-odd gluonic compound, also known as the odderon. We combine these results with a TOTEM analysis of the same C-odd exchange based on the total cross section and the ratio of the real to imaginary parts of the forward elastic strong interaction scatteringamplitude in pp scattering for which the significance is between 3.4σ and 4.6σ. The combined significance is larger than 5σ and is interpreted as the first observation of the exchange of a colorless, C-odd gluonic compound

    Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

    Full text link
    Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis

    Canagliflozin and renal outcomes in type 2 diabetes and nephropathy

    Get PDF
    BACKGROUND Type 2 diabetes mellitus is the leading cause of kidney failure worldwide, but few effective long-term treatments are available. In cardiovascular trials of inhibitors of sodium–glucose cotransporter 2 (SGLT2), exploratory results have suggested that such drugs may improve renal outcomes in patients with type 2 diabetes. METHODS In this double-blind, randomized trial, we assigned patients with type 2 diabetes and albuminuric chronic kidney disease to receive canagliflozin, an oral SGLT2 inhibitor, at a dose of 100 mg daily or placebo. All the patients had an estimated glomerular filtration rate (GFR) of 30 to <90 ml per minute per 1.73 m2 of body-surface area and albuminuria (ratio of albumin [mg] to creatinine [g], >300 to 5000) and were treated with renin–angiotensin system blockade. The primary outcome was a composite of end-stage kidney disease (dialysis, transplantation, or a sustained estimated GFR of <15 ml per minute per 1.73 m2), a doubling of the serum creatinine level, or death from renal or cardiovascular causes. Prespecified secondary outcomes were tested hierarchically. RESULTS The trial was stopped early after a planned interim analysis on the recommendation of the data and safety monitoring committee. At that time, 4401 patients had undergone randomization, with a median follow-up of 2.62 years. The relative risk of the primary outcome was 30% lower in the canagliflozin group than in the placebo group, with event rates of 43.2 and 61.2 per 1000 patient-years, respectively (hazard ratio, 0.70; 95% confidence interval [CI], 0.59 to 0.82; P=0.00001). The relative risk of the renal-specific composite of end-stage kidney disease, a doubling of the creatinine level, or death from renal causes was lower by 34% (hazard ratio, 0.66; 95% CI, 0.53 to 0.81; P<0.001), and the relative risk of end-stage kidney disease was lower by 32% (hazard ratio, 0.68; 95% CI, 0.54 to 0.86; P=0.002). The canagliflozin group also had a lower risk of cardiovascular death, myocardial infarction, or stroke (hazard ratio, 0.80; 95% CI, 0.67 to 0.95; P=0.01) and hospitalization for heart failure (hazard ratio, 0.61; 95% CI, 0.47 to 0.80; P<0.001). There were no significant differences in rates of amputation or fracture. CONCLUSIONS In patients with type 2 diabetes and kidney disease, the risk of kidney failure and cardiovascular events was lower in the canagliflozin group than in the placebo group at a median follow-up of 2.62 years

    Search for supersymmetry in events with one lepton and multiple jets in proton-proton collisions at root s=13 TeV

    Get PDF
    Peer reviewe
    corecore