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31.
Objective: Asian Indian subjects have a high tendency to develop Type 2 diabetes even though obesity is relatively uncommon. We evaluated the serum leptin levels in a group of non-obese Type 2 diabetic patients from Mumbai, Western India.Design: Cross sectional study.Methods: A total of 104 subjects consisting of 28 with Type 2 diabetes, 16 with impaired glucose tolerance and 60 age and sex-matched control subjects were given 75 g oral glucose tolerance test. Fasting serum leptin (IRMA), insulin and C-peptide were measured along with fasting and 2 h plasma glucose. The relation between these variables was studied by univariate and multiple regression analysis.Results: Type 2 diabetes was associated with marked (50–60%) reduction in serum leptin levels, in both men and women. Women, but not men, with impaired glucose tolerance exhibited 60% lower leptin. Serum leptin levels were positively correlated to body mass index (BMI; r = 0.501, p = 0.001) and calculated body fat percent (r = 0.525, p = 0.001) in all the study subjects with a better correlation in the normal subjects (r = 0.562 for BMI and 0.735 for body fat). On the other hand, serum leptin showed significant correlation to serum insulin (r = 0.362, p = 0.008) only in subjects with diabetes or IGT. In the multiple regression model, BMI was the only independent predictor of leptin, in all the subjects. However, in subjects with diabetes or impaired glucose tolerance, waist circumference (p = 0.003), gender (p = 0.007) and body fat (p = 0.009) were significant predictors of leptin, besides BMI. Gender-specific multiple regression revealed serum insulin as an independent predictor of leptin in men (p = 0.026). Therefore, lower serum leptin levels in diabetes is partly due to increased waist circumference, decreased BMI and male sex. These observations are consistent with the view that leptin levels in this cohort of non-obese Indians from Mumbai exhibit gender-specific relationship partly attributed to changes in serum insulin and waist circumference in men and to changes in BMI, in women.  相似文献   
32.
This article explores the key factors for successful employment from the viewpoints of adults with autism spectrum disorder (ASD) and employers. Two groups of individuals participated in this study, 40 adults with ASD and 35 employers. Q method was used to understand and contrast the viewpoints of the two groups. Data were analysed using by-person varimax rotation factor analysis. Results showed that although both groups appear committed to the employment process, the difference in their understanding regarding the type of workplace support required, job expectations and productivity requirements continues to hinder successful employment. These results highlight the need to facilitate communication between employees and employers to ensure a clear understanding of the needs of both groups are met. The use of an ASD-specific workplace tool may assist in facilitating the necessary communication between these two groups.  相似文献   
33.
Wiskott-Aldrich Syndrome protein (WASP) is a key regulator of the actin cytoskeleton in hematopoietic cells. Defective expression of WASP leads to multiple abnormalities in different hematopoietic cells. Despite severe impairment of T cell function, WAS patients exhibit a high prevalence of autoimmune disorders. We attempted to induce EAE, an animal model of organ-specific autoimmunity affecting the CNS that mimics human MS, in Was−/− mice. We describe here that Was−/− mice are markedly resistant against EAE, showing lower incidence and milder score, reduced CNS inflammation and demyelination as compared to WT mice. Microglia was only poorly activated in Was−/− mice. Antigen-induced T-cell proliferation, Th-1 and -17 cytokine production and integrin-dependent adhesion were increased in Was−/− mice. However, adoptive transfer of MOG-activated T cells from Was−/− mice in WT mice failed to induce EAE. Was−/− mice were resistant against EAE also when induced by adoptive transfer of MOG-activated T cells from WT mice. Was+/− heterozygous mice developed an intermediate clinical phenotype between WT and Was−/− mice, and they displayed a mixed population of WASP-positive and -negative T cells in the periphery but not in their CNS parenchyma, where the large majority of inflammatory cells expressed WASP. In conclusion, in absence of WASP, T-cell responses against a CNS autoantigen are increased, but the ability of autoreactive T cells to induce CNS autoimmunity is impaired, most probably because of an inefficient T-cell transmigration into the CNS and defective CNS resident microglial function.  相似文献   
34.
Generator of spatial magnetic field is one of most recent achievements among the magnetostimulators. This apparatus allows to obtain the rotating magnetic field. This new method may be more effective than other widely used techniques of magnetostimulation and magnetotherapy. We investigated the influence of alternating, spatial magnetic field on the regeneration of the crushed rat sciatic nerves. Functional and morphological evaluations were used. After crush injury of the right sciatic nerve, Wistar C rats (n?=?80) were randomly divided into four groups (control and three experimental). The experimental groups (A, B, C) were exposed (20?min/day, 5?d/week, 4 weeks) to alternating spatial magnetic field of three different intensities. Sciatic Functional Index (SFI) and tensometric assessments were performed every week after nerve crush. Forty-eight hours before the sacrificing of animals, DiI (1,1’-di-octadecyl-3,3,3’,3’-tetramethyloindocarbocyanine perchlorate) was applied 5?mm distally to the crush site. Collected nerves and dorsal root ganglia (DRG) were subjected to histological and immunohistochemical staining. The survival rate of DRG neurons was estimated. Regrowth and myelination of the nerves was examined. The results of SFI and tensometric assessment showed improvement in all experimental groups as compared to control, with best outcome observed in group C, exposed to the strongest magnetic field. In addition, DRG survival rate and nerve regeneration intensity were significantly higher in the C group. Above results indicate that strong spatial alternating magnetic field exerts positive effect on peripheral nerve regeneration and its application could be taken under consideration in the therapy of injured peripheral nerves.  相似文献   
35.
IntroductionDisease activity and therapy show an impact on cellular and serological parameters in patients with systemic lupus erythematosus (SLE). This study was performed to compare the influence of mycophenolate mofetil (MMF) and cyclophosphamide (CYC) therapy on these parameters in patients with flaring, organ-threatening disease.MethodsSLE patients currently receiving CYC (n = 20), MMF (n = 25) or no immunosuppressive drugs (n = 22) were compared using a cross-sectional design. Median disease activity and daily corticosteroid dose were similar in these treatment groups. Concurrent medication, organ manifestations, and disease activity were recorded, and cellular and serological parameters were determined by routine diagnostic tests or flow cytometric analysis. In addition follow-up data were obtained from different sets of patients (CYC n = 24; MMF n = 23).ResultsAlthough both drugs showed a significant effect on disease activity and circulating B cell subsets, only MMF reduced circulating plasmablasts and plasma cells as well as circulating free light chains within three months of induction therapy. Neither MMF nor CYC were able to reduce circulating memory B cells. MMF lowered IgA levels more markedly than CYC. We did not observe a significant difference in the reduction of IgG levels or anti-dsDNA antibodies comparing patients receiving MMF or CYC. In contrast to MMF, induction therapy with CYC was associated with a significant increase of circulating CD8+ effector T cells and plasmacytoid dendritic cells (PDCs) after three months.ConclusionsThe results indicate differences between MMF and CYC with regard to the mechanism of action. MMF, but not CYC, treatment leads to a fast and enduring reduction of surrogate markers of B cell activation, such as circulating plasmablasts, plasma cells and free light chains but a comparable rate of hypogammaglobulinemia.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-015-0603-8) contains supplementary material, which is available to authorized users.  相似文献   
36.
Immunity induced by Plasmodium vivax infection leads to memory T cell recruitment activated during "relapse" or "re-infection". This study aims to characterise memory T cells in patients with acute or convalescent P. vivax infection. Lymphocytes were collected from patients infected by P. vivax, immune controls and naive controls. The proportion of immature memory T cells, expressing CD45RO(+)CD27(+), and mature cells lacking CD27 was assessed. A statistically significant increase in the median percentage of memory T cell subsets expressing CD4(+) was observed in material from patients with an acute infection compared with that from either naive or immune controls. The high percentage of memory T cells in infected patients was maintained until 60 days post treatment. The immune controls living in a malaria endemic area had a somewhat increased proportion of memory T cell subsets expressing CD8(+). An approximately three-fold increase of these cell types was shown in patients with an acute infection and the level persisted until 60 days post treatment. Phenotypic characterisation of the peripheral lymphocytes during acute infection revealed that a large fraction of the lymphocytes carried the gammadelta phenotypes suggesting a role for these cells in the early response against P. vivax. Very low levels of P. vivax specific antibody were found. This might suggest that cell-mediated immunity may play a greater role in the development of naturally acquired protection against P. vivax infection than humoral immunity. Our results provide further insight into the mechanism of cell-mediated immunity to P. vivax infection that could be important for the future development of a successful vaccine and anti-malarial drug designation.  相似文献   
37.
Malaria signature on human genome is marked by several gene polymorphisms. HemoglobinAS (HbAS) is known to protect against severe malaria, but barely proved to protect against uncomplicated malaria (UM). Similarly, the influence of FcγRIIa-RH131 polymorphism on malaria is controversial. Polymorphisms in both genes were examined and levels of IgG subclasses against four malaria antigens were measured for 250 Fulani’s from Daraweesh, eastern Sudan. Morbidity data for up to nine years was available for 214 donors. Number of malaria episodes experienced by each individual during the study period was used as indicator for susceptibility to UM. PCR and RFLP were used for donors DNA genotyping and ELISA for antibodies measurement. Results revealed that neither FcγRIIa-RH131 alleles/genotypes nor HbAA/AS was significantly associated with malaria morbidity or with levels of IgG to test antigens. Both polymorphisms were in Hardy–Weinberg Equilibrium, interestingly, there was strong association between the two polymorphisms (linkage disequilibrium – LD) with D′ = 0.89. The association between the two polymorphisms was confirmed by analysis of independent material from a neighboring village. In conclusion, in Daraweesh both FcγRIIa-RH131 and HbAA/AS genotypes, independently or together, were not major markers for UM susceptibility, however, marked LD was observed between the two polymorphisms.  相似文献   
38.
ABSTRACT: BACKGROUND: Realist synthesis is an increasingly popular approach to the review and synthesis of evidence, which focuses on understanding the mechanisms by which an intervention works (or not). There are few published examples of realist synthesis. This paper therefore fills a gap by describing, in detail, the process used for a realist review and synthesis to answer the question 'what interventions and strategies are effective in enabling evidence-informed healthcare?' The strengths and challenges of conducting realist review are also considered. METHODS: The realist approach involves identifying underlying causal mechanisms and exploring how they work under what conditions. The stages of this review included: defining the scope of the review (concept mining and framework formulation); searching for and scrutinising the evidence; extracting and synthesising the evidence; and developing the narrative, including hypotheses. RESULTS: Based on key terms and concepts related to various interventions to promote evidenceinformed healthcare, we developed an outcome-focused theoretical framework. Questions were tailored for each of four theory/intervention areas within the theoretical framework and were used to guide development of a review and data extraction process. The search for literature within our first theory area, change agency, was executed and the screening procedure resulted in inclusion of 52 papers. Using the questions relevant to this theory area, data were extracted by one reviewer and validated by a second reviewer. Synthesis involved organisation of extracted data into evidence tables, theming and formulation of chains of inference, linking between the chains of inference, and hypothesis formulation. The narrative was developed around the hypotheses generated within the change agency theory area. CONCLUSIONS: Realist synthesis lends itself to the review of complex interventions because it accounts for context as well as outcomes in the process of systematically and transparently synthesising relevant literature. While realist synthesis demands flexible thinking and the ability to deal with complexity, the rewards include the potential for more pragmatic conclusions than alternative approaches to systematic reviewing. A separate publication will report the findings of the review.  相似文献   
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40.
The sodium (Na+)-calcium (Ca2+) exchanger 1 (NCX1) is an important regulator of intracellular Ca2+ homeostasis. Serine 68-phosphorylated phospholemman (pSer-68-PLM) inhibits NCX1 activity. In the context of Na+/K+-ATPase (NKA) regulation, pSer-68-PLM is dephosphorylated by protein phosphatase 1 (PP1). PP1 also associates with NCX1; however, the molecular basis of this association is unknown. In this study, we aimed to analyze the mechanisms of PP1 targeting to the NCX1-pSer-68-PLM complex and hypothesized that a direct and functional NCX1-PP1 interaction is a prerequisite for pSer-68-PLM dephosphorylation. Using a variety of molecular techniques, we show that PP1 catalytic subunit (PP1c) co-localized, co-fractionated, and co-immunoprecipitated with NCX1 in rat cardiomyocytes, left ventricle lysates, and HEK293 cells. Bioinformatic analysis, immunoprecipitations, mutagenesis, pulldown experiments, and peptide arrays constrained PP1c anchoring to the K(I/V)FF motif in the first Ca2+ binding domain (CBD) 1 in NCX1. This binding site is also partially in agreement with the extended PP1-binding motif K(V/I)FF-X5–8Φ1Φ2-X8–9-R. The cytosolic loop of NCX1, containing the K(I/V)FF motif, had no effect on PP1 activity in an in vitro assay. Dephosphorylation of pSer-68-PLM in HEK293 cells was not observed when NCX1 was absent, when the K(I/V)FF motif was mutated, or when the PLM- and PP1c-binding sites were separated (mimicking calpain cleavage of NCX1). Co-expression of PLM and NCX1 inhibited NCX1 current (both modes). Moreover, co-expression of PLM with NCX1(F407P) (mutated K(I/V)FF motif) resulted in the current being completely abolished. In conclusion, NCX1 is a substrate-specifying PP1c regulator protein, indirectly regulating NCX1 activity through pSer-68-PLM dephosphorylation.  相似文献   
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