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251.
Plasmodium vivax malaria caused is a public health problem that produces very high morbidity worldwide. During invasion of red blood cells the parasite requires the intervention of high molecular weight complex rhoptry proteins that are also essential for cytoadherence. PfClag9, a member of the RhopH multigene family, has been identified as being critical during Plasmodium falciparum infection. This study describes identifying and characterizing the pfclag9 ortholog in P. vivax (hereinafter named pvclag7). The pvclag7 gene is transcribed at the end of the intraerythrocytic cycle and is recognized by sera from humans who have been infected by P. vivax. PvClag7 subcellular localization has been also determined and, similar to what occurs with PfClag9, it co-localize with other proteins from the Rhoptry high molecular weight complex.  相似文献   
252.
The purpose of this study was to determine if excess fat negatively affects relative strength and walking gait performance in overweight, older women. Twenty-five older women (65–80 yr) were separated into normal weight (BMI < 25 kg m−2, n = 11) and overweight groups (BMI ? 25 kg m−2, n = 14). Strength and rate of torque development (RTD) of the knee extensors and flexors, ankle plantarflexors and dorsiflexors were measured. Participants walked at standard and maximal speeds during which muscle activation, spatiotemporal and kinetic gait variables were measured. Relative to mass, overweight older women had 24% lower maximal torque and 38% lower RTD than normal weight women. Maximal walking speed was slower in overweight (1.25 ± 0.22 vs. 1.54 ± 0.25 m s−1, P = 0.004) and was correlated to strength (r = 0.53, P < 0.01) and fat mass (r = −0.65, P = 0.001). At maximal speed, overweight had 11% lower vertical ground reaction force relative to mass, 8% slower stride rate, 12% shorter strides, 13% longer foot–ground contact times, 21% longer double-limb support times, 65% greater knee extensor and 78% greater plantarflexor activation (P < 0.05). Overweight, older women demonstrated altered gait and reduced walking performance related to poor relative strength and rate of torque development of lower-extremity muscles.  相似文献   
253.
Insulin increases the rate of glucose transport into fat and muscle cells by stimulating the translocation of intracellular Glut 4-containing vesicles to the plasma membrane. This results in a marked increase in the amount of the facilitative glucose transporter Glut 4 at the cell surface, allowing for an enhanced glucose uptake. This process requires a continuous cycling through the early endosomes, a Glut 4 specific storage compartment and the plasma membrane. The main effect of insulin is to increase the rate of Glut 4 trafficking from its specific storage compartment to the plasma membrane. The whole phenomenon involves signal transduction from the insulin receptor, vesicle trafficking (sorting and fusion processes) and actin cytoskeleton modifications, which are all supposed to require small GTPases. This review describes the potential role of the various members of the Ras, Rad, Rho, Arf and Rab families in the traffic of the Glut 4-containing vesicles.  相似文献   
254.
Type 2 diabetes mellitus (T2DM) is a metabolic condition with an elevated impact on cardiovascular (CV) risk. The innovative therapeutic approaches for T2DM - incretin-based therapies (IBTs), including glucagon-like peptide 1 (GLP-1) receptor agonists, have become popular and more widely used in recent years. The available scientific data from clinical studies and clinical practice highlights their beyond glucose-lowering effects, which is achieved without any increase in hypoglycaemia. The former effects include reduction in body weight, lipids, blood pressure, inflammatory markers, oxidative stress, endothelial dysfunction, and subclinical atherosclerosis, thus reducing and potentially preventing CV events. In fact, the introduction of IBTs is one of the key moments in the history of diabetes research and treatment. Such therapeutic strategies allow customization of antidiabetic treatment to each patient's need and therefore obtain better metabolic control with reduced CV risk. The aim of the present paper is to provide a comprehensive overview of the effects of GLP-1RA on various cardiometabolic markers and overall CV risk, with particular attention on recent CV outcome studies and potential mechanisms. In particular, the effects of liraglutide on formation and progression of atherosclerotic plaque and mechanisms explaining its cardioprotective effects are highlighted.  相似文献   
255.
Vibrational spectroscopic techniques can detect small variations in molecular content, linked with disease, showing promise for screening and early diagnosis. Biological fluids, particularly blood serum, are potentially valuable for diagnosis purposes. The so‐called Low Molecular Weight Fraction (LMWF) contains the associated peptidome and metabolome and has been identified as potentially the most relevant molecular population for disease‐associated biomarker research. Although vibrational spectroscopy can deliver a specific chemical fingerprint of the samples, the High Molecular Weight Fraction (HMWF), composed of the most abundant serum proteins, strongly dominates the response and ultimately makes the detection of minor spectral variations a challenging task. Spectroscopic detection of potential serum biomarkers present at relatively low concentrations can be improved using pre‐analytical depletion of the HMWF. In the present study, human serum fractionation by centrifugal filtration was used prior to analysis by Attenuated Total Reflection infrared spectroscopy. Using a model sample based on glycine spiked serum, it is demonstrated that the screening of the LMWF can be applied to quantify blinded concentrations up to 50 times lower. Moreover, the approach is easily transferable to different bodily fluids which would support the development of more efficient and suitable clinical protocols exploring vibrational spectroscopy based ex‐vivo diagnostic tools.

Revealing serum LMWF for spectral serological diagnostic applications.  相似文献   

256.
BackgroundWhile the breast cancer risk associated with increasing adult BMI in postmenopausal women can be explained by increases in concentrations of endogenous estrogens the biologic mechanisms behind the inverse association between adolescent BMI and breast cancer risk are still a subject of controversial debate.MethodsWe investigated the association of breast cancer with body size and changes in body size across life time estimated by age-specific BMI Z scores and changes in BMI Z scores from teenage years to middle age in an age-matched population-based case-control study of 2994 Australian women. Logistic regression adjusted for the matching factor age and further potential confounders was used.ResultsAdolescent body leanness in postmenopausal women and excess adult weight gain in all study participants were associated with an increased breast cancer risk with an odds ratio [95% confidence interval] of 1.29 [1.08,1.54] and 1.31 [1.09,1.59], respectively. Interaction analyses restricted to postmenopausal women revealed an increased risk of breast cancer in those who were lean during adolescence and gained excess weight during adulthood (odds ratio [95% confidence interval]: 1.52 [1.19,1.95]) but not in women who were lean during adolescence and did not gain excess weight during adulthood (1.20 [0.97,1.48]) and not in women who were not lean during adolescence and but gained excess weight during adulthood (1.10 [0.95,1.27]) compared to postmenopausal women who were neither lean during adolescence nor gained excess weight.ConclusionIn postmenopausal women adolescent leanness was only associated with increased breast cancer risk when excess weight was gained during adulthood.  相似文献   
257.
The global prevalence of weight loss is increasing, especially in young women. However, the extent and mechanisms by which maternal weight loss affects the offspring is still poorly understood. Here, using an enriched environment (EE)-induced weight loss model, we show that maternal weight loss improves general health and reprograms metabolic gene expression in mouse offspring, and the epigenetic alterations can be inherited for at least two generations. EE in mothers induced weight loss and its associated physiological and metabolic changes such as decreased adiposity and improved glucose tolerance and insulin sensitivity. Relative to controls, their offspring exhibited improved general health such as reduced fat accumulation, decreased plasma and hepatic lipid levels, and improved glucose tolerance and insulin sensitivity. Maternal weight loss altered gene expression patterns in the liver of offspring with coherent down-regulation of genes involved in lipid and cholesterol biosynthesis. Epigenomic profiling of offspring livers revealed numerous changes in cytosine methylation depending on maternal weight loss, including reproducible changes in promoter methylation over several key lipid biosynthesis genes, correlated with their expression patterns. Embryo transfer studies indicated that oocyte alteration in response to maternal metabolic conditions is a strong factor in determining metabolic and epigenetic changes in offspring. Several important lipid metabolism-related genes have been identified to partially inherit methylated alleles from oocytes. Our study reveals a molecular and mechanistic basis of how maternal lifestyle modification affects metabolic changes in the offspring.  相似文献   
258.
Impact of bariatric surgery on type 2 diabetes   总被引:4,自引:0,他引:4  
The management and prevention of diabetes through lifestyle modifications and weight loss should be the mainstay of therapy in appropriate candidates. Although the results from the Diabetes Prevention Trial and the Finnish Prevention Study support this approach, over 95% of patients not participating in a prevention research study are unable to achieve and maintain any significant weight loss over time. Bariatric surgery for weight loss is an emerging option for more sustainable weight loss in the severely obese subject, especially when obesity is complicated by diabetes or other co-morbidities. The two most common types of procedures currently used in the United States are adjustable gastric bands and Roux-en-Y gastric bypass. These procedures can be performed laparoscopically, further reducing the perioperative morbidity and mortality associated with the surgery. While the gastric bypass procedure usually results is greater sustained weight loss (40–50%) than adjustable gastric banding (20–30%), it also carries greater morbidity and nutritional/metabolic issues, such as deficiencies in iron, B12, calcium, and vitamin D. Following bariatric surgery most subjects experience improvements in diabetes control, hypertension, dyslipidemia, and other obesity-related conditions. In patients with impaired glucose tolerance most studies report 99–100% prevention of progression to diabetes, while in subjects with diabetes prior to surgery, resolution of the disease is reported in 64–93% of the cases. While improvements in insulin resistance and beta-cell function are related to surgically induced weight loss, the rapid post-operative improvement in glycemia is possibly due to a combination of decreased nutrient intake and changes in gut hormones as a result of the bypassed intestine. Post-prandial hyperinsulinemic hypoglycemia associated with nesidioblastosis has been described in a series of patients following gastric bypass surgery, and may be related to the described changes in GLP-1 and other gut hormones.  相似文献   
259.
目的探究芦笋对高脂饮食小鼠体质量的影响。方法将实验动物随机分为正常组、高脂饮食组、高脂饮食低剂量芦笋组、高脂饮食中剂量芦笋组、高脂饮食高剂量芦笋组、高脂饮食阳性对照组。其中正常组喂食正常饲料,其余组喂食高脂饲料。分别灌胃蒸馏水(正常组、高脂饮食组)、芦笋1.05g/(kg·d)(高脂饮食低剂量芦笋组)、芦笋2.10g/(kg·d)(高脂饮食中剂量芦笋组)、芦笋4.20g/(kg·d)(高脂饮食高剂量芦笋组)、降脂理肝汤1.19g/(kg·d)(高脂饮食阳性对照组),每天2次,每次0.35mL。比较分析各组小鼠的体质量变化,同时对各组之间的雌性小鼠和雄性小鼠体质量变化进行对比。结果随饲养时间的增加,服用芦笋后的三组小鼠体质量均低于高脂饮食组,但与高脂饮食组相比差异无统计学意义(P0.05)。高脂饮食低剂量芦笋组、高脂饮食中剂量芦笋组、高脂饮食高剂量芦笋组小鼠的体质量变化率低于高脂饮食组,差异无统计学意义(P0.05)。对各组之间的雌性小鼠和雄性小鼠体质量变化进行对比可以发现雄性小鼠的体质量变化大于雌性小鼠的,差异有统计学意义(P0.05)。结论芦笋能降低高脂饮食小鼠的体质量,雄性小鼠和雌性小鼠的体质量变化存在差异。  相似文献   
260.
目的探讨孕期增重过多对孕妇肠道菌群及妊娠结局的影响。方法选取2016年10月至2017年7月中国人民解放军联勤保障部队第九六七医院行产前检查并住院分娩的孕妇及其新生儿配对,共69对,根据孕期体质量增长情况,分为孕期体质量增长正常组和孕期体质量增长过多组,收集孕妇孕晚期粪便样本,分析孕妇粪便菌群的变化;比较两组孕妇妊娠期并发症、空腹血糖水平、血脂指标[总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)和低密度脂蛋白胆固醇(LDL-C)]、新生儿出生体质量和新生儿并发症等数据。结果 (1)与孕期增重正常组相比,增重过多组孕妇肠道内肠杆菌、酵母高于增重正常组,而双歧杆菌、乳杆菌、拟杆菌低于增重正常组(Ps0.05);(2)增重过多组血清TC、TG和LDL-C水平明显增高,HDL-C水平降低(Ps0.05);(3)增重过多组妊娠期并发症发生率增加(P0.05);(4)增重过多组新生儿体质量明显增加,导致巨大儿发生率明显升高,高胆红素血症的发生率也增加(P0.05)。结论孕期增重过多孕妇肠道内菌群出现异常改变,导致母亲及子代并发症发生率增加,尽早进行干预治疗可能为降低发病率提供契机。  相似文献   
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