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31.
The aim of the study was to determine what effect weight loss had on intra‐abdominal adipose tissue (IAAT) and cardiovascular disease (CVD) risk in 135 premenopausal overweight African‐American (AA) and European‐American (EA) women matched for BMI. Blood lipids, systolic blood pressure (SBP), diastolic BP (DBP), and IAAT (computed tomography determined) were examined prior to and after an 800 kcal/day diet producing 12 kg‐weight loss. Significant decreases in IAAT (~38%), total cholesterol (TC; 3%), low‐density lipoproteins (LDLs: 6%), triglycerides (TGs: 27%), cholesterol/high‐density lipoprotein ratio (C/HDL ratio: 18%), SBP (3%), and DBP (3%) occurred while HDL increased (16%), following weight loss and 1 month energy balance. Significant interactions between time and race showed that AA women decreased TG and increased HDL proportionately less than EA women. After adjusting for ΔIAAT, none of the CVD variables significantly changed after weight loss with the exception of HDL and C/HDL ratio. After adjusting for ΔLF (leg fat), ΔTC, ΔTG, ΔLDL, and ΔC/HDL ratio were significantly different. Multiple regression showed that independent of each other, ΔIAAT was significantly and positively related to ΔTC (adjusted β = 0.24) and ΔTG (adjusted β = 0.47), and ΔLF was negatively related to ΔTC (adjusted β = ?0.19) and ΔTG (adjusted β = ?0.18). Overweight and premenopausal AA and EA women benefitted from weight loss by decreasing IAAT and improving CVD risk. The changes in IAAT were significantly related to blood lipids, but loss of LF seems to be related to reduced improvement in TC and TG. Based on these results, interventions should focus on changes on IAAT.  相似文献   
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The purpose of the present study was to determine the effectiveness of a 24-week aquatic training (AT) program, which included both aerobic and resistance components, on muscle strength (isometric and dynamic), flexibility, and functional mobility in healthy women over 60 years of age. Twenty-two subjects were assigned randomly to either an AT (n = 12) or a control (C, n = 10) group. Volunteers participated in a supervised shallow-water exercise program for 60 minutes a day, 3 days a week; the exercise program consisted of a 10-minute warm-up and stretching, 25 minutes of endurance-type exercise (dancing) at 80% of heart rate (HR)(max), 20 minutes of upper- and lower-body resistance exercises with specialized water-resistance equipment, and a 5-minute cool down. Maximal isometric torque of knee extensors (KEXT) and knee flexors (KFLEX) were evaluated by a Cybex Norm dynamometer, grip strength (HGR) was evaluated using a Jamar hydraulic dynamometer, and dynamic strength was evaluated via the 3 repetition maximum (3RM) test for chest press, knee extension, lat pull down, and leg press. Jumping performance was evaluated using the squat jump (SJ), functional mobility with the timed up-and-go (TUG) test, and trunk flexion with the sit-and-reach test. Body composition was measured using the bioelectrical impedance method. The AT induced significant improvements in KEXT (10.5%) and KFLEX (13.4%) peak torque, HGR strength (13%), 3RM (25.7-29.4%), SJ (24.6%), sit-and-reach (11.6%), and TUG (19.8%) performance. The AT group demonstrated a significant increase in lean body mass (3.4%). No significant changes in these variables were observed in the C group. The results indicate that AT, with both aerobic and resistance components, is an alternative training method for improving neuromuscular and functional fitness performance in healthy elderly women.  相似文献   
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Heptakis(2,3-di-O-acetyl-6-bromo-6-deoxy)cyclomaltoheptaose has been characterized in aqueous solution by 1D and 2D NMR spectroscopy and in the solid state by X-ray crystallography. In methanol solution, the acetyl groups were found to interact with both inward and outward-pointing protons. This and the strong deshielding of the bridging carbons, relative to the nonacetylated precursor, indicate macrocyclic flexibility. In the crystalline state the macrocycle exists as a methanol complex. It exhibits elliptical distortion, all glucose residues been tilted with their primary side toward the cavity. The existing strain due to the congestion of 14 acetyl groups at the secondary site is relieved by two glucose rings acquiring the rarely observed skew-boat conformation, (0)S(2), by the increased tilting of two glucose residues, as well as by minor variations of the torsion angles of the acetyl groups. The seven bromine atoms are quite accessible to nucleophiles.  相似文献   
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In this study, we report the organization of cytoskeletal and large transmembrane proteins at the inhibitory and activating NK cell immunological or immune synapse (IS). Filamentous actin accumulates at the activating, but not the inhibitory, NK cell IS. However, surprisingly, ezrin and the associated protein CD43 are excluded from the inhibitory, but not the activating, NK cell IS. This distribution of ezrin and CD43 at the inhibitory NK cell IS is similar to that previously seen at the activating T cell IS. CD45 is also excluded from the inhibitory, but not activating, NK cell IS. In addition, electron microscopy reveals wide and narrow domains across the synaptic cleft. Target cell HLA-C, located by immunogold labeling, clusters where the synaptic cleft spans the size of HLA-C bound to the inhibitory killer Ig-like receptor. These data are consistent with assembly of the NK cell IS involving a combination of cytoskeletal-driven mechanisms and thermodynamics favoring the organization of receptor/ligand pairs according to the size of their extracellular domains.  相似文献   
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Adapter molecules that promote protein-protein interactions play a central role in T lymphocyte differentiation and activation. In this study, we examined the role of the T lymphocyte-expressed adapter protein and Src kinase substrate, Sin, on thymocyte function using transgenic mice expressing an activated, truncated allele of Sin (SinDeltaC). We found that SinDeltaC expression led to reduced numbers of CD4(+) and CD8(+) single-positive cells and reduced thymic cellularity due to increased thymocyte apoptosis. Because the adapter properties of Sin are mediated by tyrosine-based motifs and given that Sin is a substrate for Src tyrosine kinases, we examined the involvement of these kinases in the inhibitory effects of SinDeltaC. We found that in transgenic thymocytes, SinDeltaC was constitutively phosphorylated by the Src kinase Fyn, but not by the related kinase Lck. Using SinDeltaC and fyn(-/-) animals, we also found that the expression of Fyn was required for the inhibitory effect of SinDeltaC on thymocyte apoptosis but not for SinDeltaC-mediated inhibition of T cell maturation. The inhibitory effect of SinDeltaC on thymocyte maturation correlated with defective activation of the mitogen-activated protein kinase extracellular signal-regulated kinase. Our results suggest that the Sin mutant inhibits thymocyte differentiation through Fyn-dependent and -independent mechanisms and that endogenous Sin may be an important regulator of thymocyte development.  相似文献   
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Strongly concentration dependent, (1)H NMR chemical shifts of the non-steroidal anti-inflammatory drug acemetacin sodium salt (sodium [[1-(4-chlorobenzoyl)-5-methoxy-2-methylindol-3-yl]acetoxy]acetate), were observed in aqueous solution. Self-titration and nOe experiments, point to a self-association model where stacking takes place via the indole portion of the drug. In addition, conformational isomerism (atropisomerism) of the anti to syn form was confirmed. Further increase of the concentration eventually led to stable chemical shifts and nearly simultaneous appearance of microcrystals. In the presence of betaCD, 1:1 inclusion complexation occurred through the p-chlorobenzoyl part of the drug, whereas with excess betaCD the indole part seemed to participate to a minor degree. The anti isomer is suggested to be involved in the inclusion process. In addition, aggregation of acemetacin was also evident, as competing with the conformational and inclusion equilibria. The present case demonstrates that many competitive processes are simultaneously active in a seemingly simple system. The measurements were strongly dependent upon the pH and use of buffered solutions was mandatory. Finally, for the quantitative analysis of acemetacin in the presence of betaCD, a special HPLC method was developed. The stability of the drug, studied by the identification of the degradation products and the pseudo-first order rate of hydrolysis, was found to be unaffected by the presence of betaCD.  相似文献   
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Our studies have concentrated on elucidating the role of the signaling protein Sin in T-lymphocyte function. We have previously shown that Sin overexpression inhibits T-lymphocyte development and activation. Here we show that Sin-deficient mice exhibit exaggerated immune responses characterized by enhanced cytokine secretion and T-cell-dependent antibody production. Excessive T-cell responses in young mice correlate with spontaneous development of inflammatory lesions in different organs of aged Sin(-/-) mice, particularly the small intestine. The intestinal inflammation is characterized by T- and B-cell infiltrates in the lamina propria, which correlate with crypt enlargement and marked villus expansion and/or damage. Similar to the human intestinal inflammatory disorder Crohn's disease (CD), and in contrast to most mouse models of mucosal inflammation, inflammatory lesions in the gastrointestinal tract of Sin(-/-) mice are restricted to the small bowel. Taken together, these results suggest that Sin regulates immune system and T-lymphocyte function and that immune system dysfunction in the absence of Sin may underlie the pathogenesis of tissue-specific inflammation and enteropathies such as CD.  相似文献   
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