847 resultados para Penalty-based function
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RESUMO:O processo de glicosilação é a modificação pós-traducional de proteínas mais comum e está envolvido em vários processos fisiológicos e patológicos. Especificamente, certos perfis glicosídeos estão correlacionados a estados específicos de diferenciação celular, e podem modular vários eventos celulares, como sinalização celular, migração celular e interações hospedeiro-patogénio. Assim sendo, a glicosilação desempenha um papel crucial na modulação de vários processos imunológicos. No entanto, permanece por esclarecer como as estruturas glicosídicas influenciam a imunidade. Especificamente, algumas estruturas glicosídicas terminais que estão modificadas pela ligação de ácido siálico desempenham um papel importante em várias funções do sistema imune, nomeadamente migração leucocitária em contexto de inflamação e ativação de células imunes. Como tal, este trabalho teve como objectivo investigar como a expressão de certos glicanos influencia componentes importantes da resposta imune inata e adaptativa. Este trabalho está dividido em três componentes principais: 1) A imunidade está amplamente dependente da habilidade das células circulantes migrarem para os tecidos inflamados, sendo que a ligação de leucócitos à Eselectina endotelial é o primeiro passo. Assim, nós analisámos a estrutura e função dos ligandos de E-selectina que são expressos pelas células humanas mononucleares de sangue periférico (PBMCs), fornecendo novos conhecimentos para a compreensão dos intervenientes moleculares que mediam a ligação dos monócitos, células CD4+ e CD8+T e células B ao endotélio vascular. Surpreendentemente, os monócitos apresentaram maior capacidade de ligação à E-selectina comparativamente aos linfócitos. Esta observação pode ser explicada pelo facto de os monócitos humanos expressarem, uniformemente, um vasto reportório de glicoproteínas que exibem afinidade de ligação à E-selectina, nomeadamente: as glicoformas do CD43 (CD43E) e do CD44 (HCELL), em adição à já previamente reportada glicoforma da PSGL-1 (CLA). Consistentemente, a diferente capacidade que as diversas populações linfocitárias apresentam de se ligar à E-selectina, está integralmente relacionada com a sua expressão de glicoproteínas com afinidade de ligação à E-selectina. Enquanto que as células CD4+T apresentam uma elevada reatividade à E-selectina, as células CD8+T e B demonstram pouca ou nenhuma capacidade de ligação à E-selectina. Esta atividade de ligação à E-selectina das células CD4+T é conferida pela expressão de HCELL, em adição às já previamente reportadas CLA e CD43E. As células CD8+ T não expressam HCELL e apenas expressam pequenas quantidades de CLA e CD43E, enquanto que as células B não expressam ligandos de Eselectina. Mais, a exofucosilação da superfície destas células, levou ao dramático aumento da expressão dos ligandos de E-selectina em todos as populações leucocitárias, verificando-se que a criação de certos ligandos de E-selectina está dependente do tipo de célula, após fucosilação. Colectivamente, estes resultados redefinem o nosso conhecimento acerca dos mecanismos moleculares que governam o tráfico das células mononucleares de sangue periférico em contexto de inflamação. 2) A habilidade das células dendríticas (DCs) para extravasarem em locais de inflamação é crucial para o sucesso da terapia com DCs. Assim, analisámos a estrutura e função das moléculas de adesão que mediam a migração transendotelial (TEM) das DCs. Para isso, foram usadas DCs geradas a partir da diferenciação de monócitos (mo-DCS), obtidos quer pelo métodos de separação imuno-magnética de células CD14+ (CD14-S) ou por isolamento por aderência ao plástico (PA-S). Os resultados obtidos indicam que as glicoformas de ligação à Eselectina de PSGL-1, CD43 e CD44 são expressas pelas CD14-S mo-DCs, enquanto que as PA-S mo-DCs expressam apenas CLA. É importante notar que a ligação do CD44 nas mo-DCs, mas não nas PA-S mo-DCs, desencadeia a ativação e consequente adesão da VLA-4 ao endotélio na ausência de um gradiente de quimiocinas. Procedeu-se também à análise dos ligandos E-selectina expressos em mo-DCs geradas a partir de monócitos do sangue do cordão umbilical (UCB) e, inesperadamente, as UCB mo-DCs não expressam qualquer glicoproteína com reatividade à E-selectina. Além disso, a exofucosilação das mo- DCs humanas utilizando uma α(1,3)-fucosiltransferase aumenta significativamente a expressão de HCELL e, portanto, estas células apresentam uma capacidade aumentada para se ligarem à E-selectina em condições de fluxo hemodinâmico. Estes resultados destacam o papel do HCELL no desencadeamento do TEM das CD14-S mo-DCs e sugerem que estratégias para potenciar a expressão de HCELL poderão impulsionar o recrutamento de mo-DCs para locais de inflamação. 3) Outro obstáculo para alcançar o sucesso promissor de vacinas baseadas em DCs é o estabelecimento de abordagens eficientes que poderão melhorar o estado de maturação e apresentação antigénica das DCs. Por conseguinte, foram investigadas abordagens alternativas que podem superar este obstáculo. Através da remoção de ácido siálico de superfície celular das DCs, conseguiu-se induzir a maturação de DC humanas e de ratinhos. Notavelmente, tanto as DCs humanas como as de ratinho, ao serem desialiladas mostraram uma capacidade aumentada para induzir a proliferação de células T, para secretar citocinas Th1 e para induzir a morte específica de células tumorais. Em adição, as DCs desialiladas apresentam uma maior capacidade de apresentação cruzada de antigénios tumorais às células T citotóxicas. Colectivamente, o presente estudo oferece uma visão chave para optimizar a capacidade das DCs em induzir respostas imunitárias anti-tumorais, e indica que o tratamento com sialidase é uma nova tecnologia para melhorar a eficácia e aplicabilidade das vacinas baseadas em DCs. Coletivamente, os nossos resultados demostram como a glicosilação e a sua manipulação podem modular a imunidade. Concretamente, através de uma reação de exofucosilação conseguimos aumentar fortemente a capacidade de os leucócitos extravasarem para os tecidos afectados, enquanto que a remoção dos níveis de ácido siálico da superfície celular das DCs, induz potentes respostas anti-tumorais mediadas por células T citotóxicas. ---------------------------- ABSTRACT: Glycosylation is the most widely form of protein post-translational modification and is involved in many physiological and pathological processes. Specifically, certain patterns of glycosylation are associated with determined stages of cell differentiation and can modulate processes like cell-signaling and migration and host-pathogen interactions. As such, glycosylation plays a crucial role in the modulation of several immune events. However, how glycans execute this immune-modulation and, therefore, influence immunity is still poorly unknown. Specifically, some terminal sialic acid-modified determinants are known to be involved in several physiological immune processes, including leukocyte trafficking into sites of inflammation and cell immune activation. Therefore, in this work, we sought to investigate more deeply how the expression of these glycosidic structures affects events form both innate and adaptive immune responses. To this end, we divided our work into three main parts: 1) Immunity critically depends on the ability of sentinel circulating cells to infiltrate injured sites, of which leukocyte binding to endothelial E-selectin is the critical first step. Thus, we first analyzed the structure and function of the E-selectin ligands expressed on native human peripheral blood mononuclear cells (PBMCs), providing novel insights into the molecular effectors governing adhesion of circulating monocytes, and of circulating CD4+T, CD8+T and B cells, to vascular endothelium under hemodynamic shear conditions. Strikingly, monocytes show a higher ability to tether and roll on endothelial cells than lymphocyte subsets. This is due to the fact that human circulating monocytes uniformly display a wide repertoire of E-selectin binding glycoproteins, namely the E-selectin-binding glycoforms of CD43 (CD43E) and CD44 (HCELL), in addition to the previously described E-selectin-binding glycoform of PSGL-1 (CLA). In addition, we also observed a differential ability of the different lymphocyte subsets to bind to Eselectin under hemodynamic shear stress conditions, and these differences were highly correlated with their individual expression of E-selectin binding glycoproteins. While CD4+T cells show a robust E-selectin binding ability, CD8+T and B cells show little to no E-selectin reactivity. CD4+T cell potent Eselectin rolling activity is conferred by HCELL expression, in addition to the previously reported E-selectin-binding glycoproteins CD43E and CLA. CD8+T cells display no HCELL and low amounts of CLA and CD43E, whereas B cells lack E-selectin ligand expression. Moreover, enforced exofucosylation of cell surface of these cells noticeably increases expression of functional E-selectin ligands among all leukocytes subsets, with cell type-dependent specificity in the protein scaffolds that are modified. Taken together, these findings redefine our understanding of the molecular mechanisms governing the trafficking patterns of PBMCs that are relevant in the context of acute or chronic inflammatory conditions. 2) The ability of circulating dendritic cells (DCs) to extravasate at inflammatory sites is critical to the success of DC-based therapies. Therefore, we assessed the structure and function of adhesion molecules mediating the transendothelial migration (TEM) of human monocyte derived-DCs (mo-DCs), obtained either by CD14 positive immune-magnetic selection (CD14-S) or by plastic adherence of blood monocytes (PA-S). We report for the first time that the E-selectin binding glycoforms of PSGL-1, CD43 and CD44 are all expressed on CD14-S mo-DCs, in contrast to PA-S mo-DCs that express only CLA. Importantly, CD44 engagement on CD14-S mo-DCs, but not on PA-S mo-DCs, triggers VLA-4-dependent adhesiveness and programs TEM in absence of chemokine gradient. We also analyzed the E-selectin ligands expressed on mo-DCs generated from umbilical cord blood (UCB) monocytes, and unexpectedly, UCB mo-DCs do not express any glycoprotein with E-selectin reactivity. Furthermore, exoglycosylation of human mo-DCs using an α(1,3)-fucosyltransferase significantly increases expression of HCELL, and therefore exofucosylated mo-DCs exhibit an augmented ability to bind to E-selectin under hemodynamic shear stress conditions. These findings highlight a role for HCELL engagement in priming TEM of CD14-S mo-DCs, and suggest that strategies to enforce HCELL expression could boost mo-DC recruitment to inflammatory sites.3) Another obstacle to achieve the promising success of DC-based vaccines is the establishment of efficient approaches that could successfully enhance maturation and cross-presentation ability of DCs. Therefore, we investigated an alternative approach that can overcome this problem. Through removal of sialic acid content from DC cell surface we are able to elicit maturation of both human and mouse DCs. Notably, desialylated human and murine DCs showed enhanced ability to induce autologous T cell to proliferate, to secrete Th1 cytokines and to kill tumor cells. Moreover, desialylated DCs display enhanced cross-presentation of tumor antigens to cytotoxic CD8+ T cells. Collectively, this study offers key insight to optimize the ability of DCs to boost anti-tumor immune responses, and indicates that the treatment with an exogenous sialidase is a powerful new technology to improve the efficacy and applicability of DC-based vaccines. Overall, our findings show how glycosylation and its manipulation can modulate immunity. Concretely, through an exofucosylation reaction we are able to greatly augment the ability of leukocytes to extravasate into injured tissues, while removal of sialic acid moieties from cell surface of DCs, significantly potentiate their ability to induce anti-tumor cytotoxic T cell-mediate responses.
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Ornament expression fluctuates with age in many organisms. Whether these changes are adaptively plastic is poorly known. In order to understand the ultimate function of melanin-based ornaments, we studied their within-individual fluctuations and their covariation with fitness-related traits. In barn owls (Tyto alba), individuals vary from reddish-brown pheomelanic to white and from immaculate to marked with black eumelanic spots, males being less reddish and less spotted than females. During the first molt, both sexes became less pheomelanic, females displayed larger spots and males fewer spots, but the extent of these changes was not associated with reproduction. At subsequent molts, intra-individual changes in melanin-based traits covaried with simultaneous reproduction changes. Adult females bred earlier in the season and laid larger eggs when they became scattered with larger spots, while adults of both sexes produced larger broods when they became whiter. These results suggest that the production of melanin pigments and fitness-related life history traits are concomitantly regulated in a sex-specific way.
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OBJECTIVES: In this population-based study, reference values were generated for renal length, and the heritability and factors associated with kidney length were assessed. METHODS: Anthropometric parameters and renal ultrasound measurements were assessed in randomly selected nuclear families of European ancestry (Switzerland). The adjusted narrow sense heritability of kidney size parameters was estimated by maximum likelihood assuming multivariate normality after power transformation. Gender-specific reference centiles were generated for renal length according to body height in the subset of non-diabetic non-obese participants with normal renal function. RESULTS: We included 374 men and 419 women (mean ± SD, age 47 ± 18 and 48 ± 17 years, BMI 26.2 ± 4 and 24.5 ± 5 kg/m(2), respectively) from 205 families. Renal length was 11.4 ± 0.8 cm in men and 10.7 ± 0.8 cm in women; there was no difference between right and left renal length. Body height, weight and estimated glomerular filtration rate (eGFR) were positively associated with renal length, kidney function negatively, age quadratically, whereas gender and hypertension were not. The adjusted heritability estimates of renal length and volume were 47.3 ± 8.5 % and 45.5 ± 8.8 %, respectively (P < 0.001). CONCLUSION: The significant heritability of renal length and volume highlights the familial aggregation of this trait, independently of age and body size. Population-based references for renal length provide a useful guide for clinicians. KEY POINTS: • Renal length and volume are heritable traits, independent of age and size. • Based on a European population, gender-specific reference values/percentiles are provided for renal length. • Renal length correlates positively with body length and weight. • There was no difference between right and left renal lengths in this study. • This negates general teaching that the left kidney is larger and longer.
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Gestures are the first forms of conventional communication that young children develop in order to intentionally convey a specific message. However, at first, infants rarely communicate successfully with their gestures, prompting caregivers to interpret them. Although the role of caregivers in early communication development has been examined, little is known about how caregivers attribute a specific communicative function to infants' gestures. In this study, we argue that caregivers rely on the knowledge about the referent that is shared with infants in order to interpret what communicative function infants wish to convey with their gestures. We videotaped interactions from six caregiver-infant dyads playing with toys when infants were 8, 10, 12, 14, and 16 months old. We coded infants' gesture production and we determined whether caregivers interpreted those gestures as conveying a clear communicative function or not; we also coded whether infants used objects according to their conventions of use as a measure of shared knowledge about the referent. Results revealed an association between infants' increasing knowledge of object use and maternal interpretations of infants' gestures as conveying a clear communicative function. Our findings emphasize the importance of shared knowledge in shaping infants' emergent communicative skills.
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Purpose: Sirolimus (SRL) has been used to replace calcineurin inhibitors (CNI) for various indications including CNI-induced toxicity. The aim of this study was to evaluate the efficacy and safety of switching from CNI to SRL in stable renal transplant recipients (RTR) with low grade proteinuria (<1 g/24 h). Methods and materials: Between 2001 and 2007, 41 patients (20 females, 21 males; mean age 47 ± 13) were switched after a median time post-transplantation of 73.5 months (range 0.2-273.2 months). Indications for switch were CNI nephrotoxicity (39%), thrombotic micro-angiopathy (14.6%), post-transplantation cancer (24.4%), CNI neurotoxicity (7.4%), or others (14.6%). Mean follow-up after SRL switch was 23.8±16.3 months. Mean SRL dosage and through levels were 2.4 ± 1.1 mg/day and 8 ± 2.2 ug/l respectively. Immunosuppressive regiments were SRL + mycophenolate mofetil (MMF) (31.7%), SRL + MMF + prednisone (36.58%), SRL + prednisone (19.51%), SRL + Azathioprine (9.75%), or SRL alone (2.43%). Results: Mean creatinine decreased from 164 to 143 μmol/l (p <0.03), mean estimated glomerular filtration rate (eGFR) increased significantly from 50.13 to 55.01 ml/minute (p <0.00001), mean systolic and diastolic blood pressure decreased from 138 to 132 mm Hg (p <0.03) and from 83 to78 mm Hg (p <0.01), but mean proteinuria increased from 0.21 to 0.63 g/24 h (p <0.001). While mean total cholesterolemia didn't increased significantly from 5.09 to 5.56 mmol/l (p = 0.06). The main complications after SRL switch were dermatitis (19.5%), urinary tract infections (24.4%), ankle edema (13.3%), and transient oral ulcers (20%). Acute rejection after the switch occurred in 7.3% of patients (n = 3), and 2 acute rejections were successfully treated with corticosteroids and 1 did not respond to treatment (not related to switch). SRL had to be discontinued in 17% of patients (2 nephrotic syndromes, 2 severe edema, 1 acute rejection, 1 thrombotic micro-angiopathy, and 1 fever). Conclusion: In conclusion, we found that switching from CNI to SRL in stable RTR was safe and associated with a significant improvement of renal function and blood pressure. Known side-effects of SRL led to drug discontinuation in less than 20% of patients and the acute rejection rate was 7.3%. This experience underlines the importance of patient selection before switching to SRL, in particular regarding preswitch proteinuria.
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OBJECTIVE: To investigate the association of renal impairment on functional outcome and complications in stroke patients treated with IV thrombolysis (IVT). METHODS: In this observational study, we compared the estimated glomerular filtration rate (GFR) with poor 3-month outcome (modified Rankin Scale scores 3-6), death, and symptomatic intracranial hemorrhage (sICH) based on the criteria of the European Cooperative Acute Stroke Study II trial. Unadjusted and adjusted odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. Patients without IVT treatment served as a comparison group. RESULTS: Among 4,780 IVT-treated patients, 1,217 (25.5%) had a low GFR (<60 mL/min/1.73 m(2)). A GFR decrease by 10 mL/min/1.73 m(2) increased the risk of poor outcome (OR [95% CI]): (ORunadjusted 1.20 [1.17-1.24]; ORadjusted 1.05 [1.01-1.09]), death (ORunadjusted 1.33 [1.28-1.38]; ORadjusted 1.18 [1.11-1.249]), and sICH (ORunadjusted 1.15 [1.01-1.22]; ORadjusted 1.11 [1.04-1.20]). Low GFR was independently associated with poor 3-month outcome (ORadjusted 1.32 [1.10-1.58]), death (ORadjusted 1.73 [1.39-2.14]), and sICH (ORadjusted 1.64 [1.21-2.23]) compared with normal GFR (60-120 mL/min/1.73 m(2)). Low GFR (ORadjusted 1.64 [1.21-2.23]) and stroke severity (ORadjusted 1.05 [1.03-1.07]) independently determined sICH. Compared with patients who did not receive IVT, treatment with IVT in patients with low GFR was associated with poor outcome (ORadjusted 1.79 [1.41-2.25]), and with favorable outcome in those with normal GFR (ORadjusted 0.77 [0.63-0.94]). CONCLUSION: Renal function significantly modified outcome and complication rates in IVT-treated stroke patients. Lower GFR might be a better risk indicator for sICH than age. A decrease of GFR by 10 mL/min/1.73 m(2) seems to have a similar impact on the risk of death or sICH as a 1-point-higher NIH Stroke Scale score measuring stroke severity.
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QUESTIONS UNDER STUDY AND PRINCIPLES: Estimating glomerular filtration rate (GFR) in hospitalised patients with chronic kidney disease (CKD) is important for drug prescription but it remains a difficult task. The purpose of this study was to investigate the reliability of selected algorithms based on serum creatinine, cystatin C and beta-trace protein to estimate GFR and the potential added advantage of measuring muscle mass by bioimpedance. In a prospective unselected group of patients hospitalised in a general internal medicine ward with CKD, GFR was evaluated using inulin clearance as the gold standard and the algorithms of Cockcroft, MDRD, Larsson (cystatin C), White (beta-trace) and MacDonald (creatinine and muscle mass by bioimpedance). 69 patients were included in the study. Median age (interquartile range) was 80 years (73-83); weight 74.7 kg (67.0-85.6), appendicular lean mass 19.1 kg (14.9-22.3), serum creatinine 126 μmol/l (100-149), cystatin C 1.45 mg/l (1.19-1.90), beta-trace protein 1.17 mg/l (0.99-1.53) and GFR measured by inulin 30.9 ml/min (22.0-43.3). The errors in the estimation of GFR and the area under the ROC curves (95% confidence interval) relative to inulin were respectively: Cockcroft 14.3 ml/min (5.55-23.2) and 0.68 (0.55-0.81), MDRD 16.3 ml/min (6.4-27.5) and 0.76 (0.64-0.87), Larsson 12.8 ml/min (4.50-25.3) and 0.82 (0.72-0.92), White 17.6 ml/min (11.5-31.5) and 0.75 (0.63-0.87), MacDonald 32.2 ml/min (13.9-45.4) and 0.65 (0.52-0.78). Currently used algorithms overestimate GFR in hospitalised patients with CKD. As a consequence eGFR targeted prescriptions of renal-cleared drugs, might expose patients to overdosing. The best results were obtained with the Larsson algorithm. The determination of muscle mass by bioimpedance did not provide significant contributions.
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Increased serum levels of homocysteine and uric acid have each been associated with cardiovascular risk. We analyzed whether homocysteine and uric acid were associated with glomerular filtration rate (GFR) and albuminuria independently of each other. We also investigated the association of MTHFR polymorphisms related to homocysteine with albuminuria to get further insight into causality. This was a cross-sectional population-based study in Caucasians (n = 5913). Hyperhomocysteinemia was defined as total serum homocysteine ≥ 15 μmol/L. Albuminuria was defined as urinary albumin-to-creatinine ratio > 30 mg/g. Uric acid was associated positively with homocysteine (r = 0.246 in men and r = 0.287 in women, P < 0.001). The prevalence of albuminuria increased across increasing homocysteine categories (from 6.4% to 17.3% in subjects with normal GFR and from 3.5% to 14.5% in those with reduced GFR, P for trend < 0.005). Hyperhomocysteinemia (OR = 2.22, 95% confidence interval: 1.60-3.08, P < 0.001) and elevated serum uric acid (OR = 1.27, 1.08-1.50, per 100 μmol/L, P = 0.004) were significantly associated with albuminuria, independently of hypertension and type 2 diabetes. The 2-fold higher risk of albuminuria associated with hyperhomocysteinemia was similar to the risk associated with hypertension or diabetes. MTHFR alleles related to higher homocysteine were associated with increased risk of albuminuria. In the general adult population, elevated serum homocysteine and uric acid were associated with albuminuria independently of each other and of renal function.
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Lung transplantation has now been performed for more than 30 years in patients with end-stage chronic obstructive pulmonary disease (COPD). This disease is the major indication for lung transplantation, involving more than one third of the procedures worldwide. Although lung transplantation in COPD patients has clearly shown a positive impact on lung function, exercise capacity and quality of life, the survival benefit remains difficult to ascertain. Several methodological difficulties, particularly the absence of classical randomised studies, make the analysis especially challenging. There is however indirect but convincing evidence that lung transplantation can, when appropriate selection criteria are applied, provide not only an active post-transplant lifestyle but also a survival benefit for patients with COPD.
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Chronic kidney disease (CKD), impairment of kidney function, is a serious public health problem, and the assessment of genetic factors influencing kidney function has substantial clinical relevance. Here, we report a meta-analysis of genome-wide association studies for kidney function-related traits, including 71,149 east Asian individuals from 18 studies in 11 population-, hospital- or family-based cohorts, conducted as part of the Asian Genetic Epidemiology Network (AGEN). Our meta-analysis identified 17 loci newly associated with kidney function-related traits, including the concentrations of blood urea nitrogen, uric acid and serum creatinine and estimated glomerular filtration rate based on serum creatinine levels (eGFRcrea) (P < 5.0 × 10(-8)). We further examined these loci with in silico replication in individuals of European ancestry from the KidneyGen, CKDGen and GUGC consortia, including a combined total of ∼110,347 individuals. We identify pleiotropic associations among these loci with kidney function-related traits and risk of CKD. These findings provide new insights into the genetics of kidney function.
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Molecular evidence suggests that levels of vitamin D are associated with kidney function loss. Still, population-based studies are limited and few have considered the potential confounding effect of baseline kidney function. This study evaluated the association of serum 25-hydroxyvitamin D with change in eGFR, rapid eGFR decline, and incidence of CKD and albuminuria. Baseline (2003-2006) and 5.5-year follow-up data from a Swiss adult general population were used to evaluate the association of serum 25-hydroxyvitamin D with change in eGFR, rapid eGFR decline (annual loss >3 ml/min per 1.73 m(2)), and incidence of CKD and albuminuria. Serum 25-hydroxyvitamin D was measured at baseline using liquid chromatography-tandem mass spectrometry. eGFR and albuminuria were collected at baseline and follow-up. Multivariate linear and logistic regression models were used considering potential confounding factors. Among the 4280 people included in the analysis, the mean±SD annual eGFR change was -0.57±1.78 ml/min per 1.73 m(2), and 287 (6.7%) participants presented rapid eGFR decline. Before adjustment for baseline eGFR, baseline 25-hydroxyvitamin D level was associated with both mean annual eGFR change and risk of rapid eGFR decline, independently of baseline albuminuria. Once adjusted for baseline eGFR, associations were no longer significant. For every 10 ng/ml higher baseline 25-hydroxyvitamin D, the adjusted mean annual eGFR change was -0.005 ml/min per 1.73 m(2) (95% confidence interval, -0.063 to 0.053; P=0.87) and the risk of rapid eGFR decline was null (odds ratio, 0.93; 95% confidence interval, 0.79 to 1.08; P=0.33). Baseline 25-hydroxyvitamin D level was not associated with incidence of CKD or albuminuria. The association of 25-hydroxyvitamin D with eGFR decline is confounded by baseline eGFR. Sufficient 25-hydroxyvitamin D levels do not seem to protect from eGFR decline independently from baseline eGFR.
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The paracaspase MALT1 has a central role in the activation of lymphocytes and other immune cells including myeloid cells, mast cells and NK cells. MALT1 activity is required not only for the immune response, but also for the development of natural Treg cells that keep the immune response in check. Exaggerated MALT1 activity has been associated with the development of lymphoid malignancies, and recently developed MALT1 inhibitors show promising anti-tumor effects in xenograft models of diffuse large B cell lymphoma. In this review, we provide an overview of the present understanding of MALT1's function, and discuss possibilities for its therapeutic targeting based on recently developed inhibitors and animal models.
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The study centers on the power of Right-Wing Authoritarianism (RWA) and Social Dominance Orientation (SDO) as predictors of prejudice against stereotypical and nonstereotypical homosexuals under the threat of death and the threat of uncertainty. Right-wing authoritarianism (RWA) is an individual difference variable that measures the tendency for individuals to unquestionably follow those perceived to be authorities. Social Dominance Orientation (SDO) is an individual difference variable that measures the degree to which an individual prefers inequality among social groups. The RWA and SDO Scales are considered to be two of the strongest predictors of prejudice, such as prejudice against homosexuals. The study focuses on the unique predictive power of these two variables in predicting prejudice against homosexuals. The study also examines the role of situational threat in prejudice, specifically the threat of death (mortality salience) and the threat of uncertainty (uncertainty salience). Competing predictions from theories involving the threat of death (Terror Management Theory) and the threat of uncertainty (Uncertainty Management Theory) are also tested. The preference for expected information in the form of stereotypes concerning male homosexuals (that is, a stereotypical or non-stereotypical homosexual) were tested. The difference between the predictive power ofRWA and SDO was examined by measuring how these variables predict liking of a stereotypical or non-stereotypical homosexual under the threat of death, the threat of uncertainty, or a control condition. Along with completing a measure for RWA and a measure for SDO, participants were asked to think of their own death, of their being uncertain or about watching television then were asked to read about a week in the life of either a stereotypical or non-stereotypical male homosexual. Participants were then asked to evaluate the individual and his essay. Based on the participants' evaluations, results from 180 heterosexual university students show that RWA and SDO are strong predictors for disliking of a stereotypical homosexual under the threat of uncertainty and disliking of a non-stereotypical homosexual under the threat of death. Furthermore, however, results show that RWA is a particularly strong predictor of disliking of a stereotypical homosexual under the threat of uncertainty, whereas SDO is an exceptionally strong predictor of disliking of the non-stereotypical homosexual under the threat of death. This further adds to the notion that RWA and SDO are indeed unique predictors of prejudice. Implications are also explored, including the fact that the study simuhaneously examined the role of individual difference variables and situational threat variables, as well as exploratory analysis on Dominating Authoritarians.
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We study the phonon dispersion, cohesive and thermal properties of raxe gas solids Ne, Ar, Kr, and Xe, using a variety of potentials obtained from different approaches; such as, fitting to crystal properties, purely ab initio calculations for molecules and dimers or ab initio calculations for solid crystalline phase, a combination of ab initio calculations and fitting to either gas phase data or sohd state properties. We explore whether potentials derived with a certain approaxih have any obvious benefit over the others in reproducing the solid state properties. In particular, we study phonon dispersion, isothermal ajid adiabatic bulk moduli, thermal expansion, and elastic (shear) constants as a function of temperatiue. Anharmonic effects on thermal expansion, specific heat, and bulk moduli have been studied using A^ perturbation theory in the high temperature limit using the neaxest-neighbor central force (nncf) model as developed by Shukla and MacDonald [4]. In our study, we find that potentials based on fitting to the crystal properties have some advantage, particularly for Kr and Xe, in terms of reproducing the thermodynamic properties over an extended range of temperatiures, but agreement with the phonon frequencies with the measured values is not guaranteed. For the lighter element Ne, the LJ potential which is based on fitting to the gas phase data produces best results for the thermodynamic properties; however, the Eggenberger potential for Ne, where the potential is based on combining ab initio quantum chemical calculations and molecular dynamics simulations, produces results that have better agreement with the measured dispersion, and elastic (shear) values. For At, the Morse-type potential, which is based on M0ller-Plesset perturbation theory to fourth order (MP4) ab initio calculations, yields the best results for the thermodynamic properties, elastic (shear) constants, and the phonon dispersion curves.
Resumo:
Perovskite type piezoelectric and manganese oxide materials have gained a lot of attention in the field of device engineering. Lead zirconium titananium oxide (PbZri.iTiiOa or PZT) is a piezoelectric material widely used as sensors and actuators. Miniaturization of PZTbased devices will not only perfect many existing products, but also opens doors to new applications. Lanthanum manganese oxides Lai-iAiMnOa (A-divalent alkaline earth such as Sr, Ca or Ba) have been intensively studied for their colossal magnetoresistance (CMR) properties that make them applicable in memory cells, magnetic and pressure sensors. In this study, we fabricate PZT and LSMO(LCMO) heterostructures on SrTiOa substrates and investigate their temperature dependency of resistivity and magnetization as a function of the thickness of LSMO(LCMO) layer. The microstructure of the samples is analysed through TEM. In another set of samples, we study the effect of application of an electric field across the PZT layer that acts as an external pressure on the manganite layer. This verifies the correlation of lattice distortion with transport and magnetic properties of the CMR materials.