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81.
We measured the uptake of a radiolabeled analogue of glucose ([3H]FDG) into muscles during treadmill walking so as to determine whether sensory deafferentation of a limb affects the muscles' metabolic response to the exercise. The muscles on the deafferented side took up less tracer than those in the intact side with exercise, but not at rest. Extensor muscles were more affected than flexors by deafferentation. This agrees with the proposal that "reflex" inputs adjust the level of recruitment of motor units by central pattern generators.  相似文献   
82.
Summary. This study investigated if and to what extent the acute toxic effect of Cyclosporin A on pancreatic Wistar rat B cells is reversible. After 2 weeks of treatment rats developed marked glucose intolerance accompanied by reduced pancreatic insulin content due to a loss of B cells, diminished islet DNA synthesis and decreased B-cell insulin content. Cyclosporin A had accumulated in the pancreas. Three weeks after withdrawal of Cyclosporin A, pancreatic tissue concentrations of Cyclosporin A were still 100 times larger than in serum. Glucose tolerance, however, had already improved, associated with an increase of B-cell insulin content and apparent islet replication, and the insulin response of isolated islets was reduced. Five weeks after the withdrawal of Cyclosporin A, glucose tolerance was normal, but pancreatic insulin content and relative B-cell volume were still diminished in comparison to vehicle-treated controls. Eight weeks after withdrawal, the morphometric parameters had also been normalized. The results suggest that the loss of pancreatic B cells is caused by a toxic destruction, possibly combined with an apparent decrease of replicatory activity. The acute toxic effects of Cyclosporin A in pancreatic B cells are stepwise reversible.  相似文献   
83.
Energy drinks containing significant quantities of caffeine, taurine and sugar are increasingly consumed, particularly by adolescents and young adults. The putative effects of chronic ingestion of either standard energy drink, MotherTM (ED), or its sugar-free formulation (sfED) on metabolic syndrome were determined in wild-type C57BL/6J mice, in comparison to a soft drink, Coca-Cola (SD), a Western-styled diet enriched in saturated fatty acids (SFA), and a combination of SFA + ED. Following 13 weeks of intervention, mice treated with ED were hyperglycaemic and hypertriglyceridaemic, indicating higher triglyceride glucose index, which was similar to the mice maintained on SD. Surprisingly, the mice maintained on sfED also showed signs of insulin resistance with hyperglycaemia, hypertriglyceridaemia, and greater triglyceride glucose index, comparable to the ED group mice. In addition, the ED mice had greater adiposity primarily due to the increase in white adipose tissue, although the body weight was comparable to the control mice receiving only water. The mice maintained on SFA diet exhibited significantly greater weight gain, body fat, cholesterol and insulin, whilst blood glucose and triglyceride concentrations remained comparable to the control mice. Collectively, these data suggest that the consumption of both standard and sugar-free forms of energy drinks induces metabolic syndrome, particularly insulin resistance.  相似文献   
84.
The purpose of this study was to examine how gold kiwifruit pericarp (pericarp is defined as the skin of the fruit) consumption and the timing thereof affect the postprandial blood glucose profile. The study was conducted on twelve healthy volunteers (six men and six women). According to our results, the simultaneous intake of gold kiwifruit with bread and the prior intake of gold kiwifruit evidently suppressed the postprandial blood glucose elevation compared with exclusive bread intake. There was no significant difference in postprandial blood glucose changes between the ingestion of gold kiwifruit pericarp and pulp and that of gold kiwifruit pulp only. The highest postprandial blood glucose elevation was suppressed by 27.6% and the area under the blood glucose elevation curve by 29.3%, even with the exclusive ingestion of gold kiwifruit pulp. We predicted that the ingestion of both the pericarp and pulp of gold kiwifruit would reduce the postprandial blood glucose elevation to a greater extent than that of gold kiwifruit pulp only; however, there was no significant difference between the two. These results indicate that gold kiwifruit consumption significantly suppresses the postprandial blood glucose elevation regardless of pericarp presence or absence and the timing of ingestion.  相似文献   
85.
The effects of exercise on nutrient digestion and absorption in the intestinal tract are not well understood. A few studies have reported that exercise training increases the expression of molecules involved in carbohydrate digestion and absorption. Exercise was also shown to increase the blood concentration of glucagon-like peptide-2 (GLP-2), which regulates carbohydrate digestion and absorption in the small intestine. Therefore, we investigated the effects of exercise on the expression of molecules involved in intestinal digestion and absorption, including GLP-2. Six-week-old male mice were divided into a sedentary (SED) and low-intensity exercise (LEx) group. LEx mice were required to run on a treadmill (12.5 m/min, 1 h), whereas SED mice rested. All mice were euthanized 1 h after exercise or rest, and plasma, jejunum, ileum, and colon samples were collected, followed by analysis via IHC, EIA, and immunoblotting. The levels of plasma GLP-2 and the jejunum expression of the GLP-2 receptor, sucrase-isomaltase (SI), and glucose transporter 2 (GLUT2) were higher in LEx mice. Thus, we showed that acute low-intensity exercise affects the expression of molecules involved in intestinal carbohydrate digestion and absorption via GLP-2. Our results suggest that exercise might be beneficial for small intestine function in individuals with intestinal frailty.  相似文献   
86.
Ageing is associated with postprandial muscle vascular and metabolic dysfunction, suggesting vascular modifying interventions may be of benefit. Reflecting this, we investigated the impact of acute cocoa flavanol (450–500 mg) intake (versus placebo control) on vascular (via ultrasound) and glucose/insulin metabolic responses (via arterialised/venous blood samples and ELISA) to an oral nutritional supplement (ONS) in twelve healthy older adults (50% male, 72 ± 4 years), in a crossover design study. The cocoa condition displayed significant increases in m. vastus lateralis microvascular blood volume (MBV) in response to feeding at 180 and 240-min after ONS consumption (baseline: 1.00 vs. 180 min: 1.09 ± 0.03, p = 0.05; 240 min: 1.13 ± 0.04, p = 0.002), with MBV at these timepoints significantly higher than in the control condition (p < 0.05). In addition, there was a trend (p = 0.058) for MBV in m. tibialis anterior to increase in response to ONS in the cocoa condition only. Leg blood flow and vascular conductance increased, and vascular resistance decreased in response to ONS (p < 0.05), but these responses were not different between conditions (p > 0.05). Similarly, glucose uptake and insulin increased in response to ONS (p < 0.05) comparably between conditions (p > 0.05). Thus, acute cocoa flavanol supplementation can potentiate oral feeding-induced increases in MBV in older adults, but this improvement does not relay to muscle glucose uptake.  相似文献   
87.
With an increasing prevalence of diabetes worldwide, effective dietary strategies for blood glucose control are crucial. As carbohydrates make up approximately 50% of the diet, it is neither practical nor advisable to avoid them altogether. Most of the carbohydrate in the diet is derived from starch, found in potatoes, pasta, rice and bread. These foods are often processed in some way before consumption, yet little is known about the effects processing, such as chilling and reheating, has on the glycaemic response, particularly when the food is consumed in the context of a mixed meal. This article introduces the SPUD project, a BBSRC DRINC‐funded initiative. Taking the potato as the model carbohydrate, this project will investigate, via in vitro and in vivo studies, the effects of domestic food processing techniques on the glycaemic response. A final study, utilising intrinsically labelled potato and a dual stable isotope methodology, will model glucose flux data to determine the underlying mechanisms of action.  相似文献   
88.
目的:探讨治疗创伤对高血压性脑出血患者血糖及按期预后的影响。方法:采用局麻血肿穿刺抽吸治疗(治疗组32例)及全麻外科手术血肿清除治疗(对照组30例),比较术后的血糖变化,结果:治疗组血肿穿刺抽吸后血糖高峰值水平显著低于对照组(P<0.01),而治疗后第1,2,周血糖降至正常者治疗组显著高于对照组(P<0.05),病死率治疗组6.25%,对照组26.7%),两组比较差异显著(P<0.05),结论:高血压性脑出血患者血肿穿刺抽吸治疗较外科手术血肿清除治疗有血糖峰值低,恢复正常的速度快,病死率低,对脑组织的损伤小等优点,值得临床推广。  相似文献   
89.
目的 :研究瘦素受体基因Gln2 2 3Arg等位基因与不同葡萄糖耐量中血清瘦素及其它代谢指标的关系。方法 :运用聚合酶链反应 限制性片段长度多态性 (PCR RFLP)方法测定无亲缘关系 ,不同葡萄糖耐量 198例北京地区汉族人的瘦素受体基因Gln2 2 3Arg等位基因 ,同时分析其与临床资料的相关性。结果 :不同等位基因型的瘦素水平无显著差异 ,而在葡萄糖耐量减低 (IGT)男性 ,Gln2 2 3Arg等位基因有较高的胆固醇水平 [(7 2 6±1 95 )和 (5 31± 1 31)mmol/L ,P =0 0 4]和较高的收缩压 [(18 8± 1 2 )和 (17 2± 1 6 )kPa ,P =0 0 3]。结论 :瘦素受体Gln2 2 3Arg基因多态性与不同葡萄糖耐量的血清瘦素无关 ,但与机体代谢有一定关系  相似文献   
90.
肝硬化患者胰高糖素负荷的血c—AMP及血糖反应性观察   总被引:2,自引:1,他引:1  
目的观察肝硬化患者对胰高糖素负荷后的血c-AMP及血糖反应能力.方法38例肝硬化患者按Child-Pugh肝功能分级,分为A级(10例),B级(14例),C级(14例)三个亚组.11例健康者为对照组.清晨空腹静卧,套管针肘静脉穿刺并固定15min后采集基础血c-AMP和血糖标本,即刻以每公斤体重2.5μg胰高糖素快速静脉注射(30s内),分别于注射后5,15,30及45min采集血c-AMP和血糖标本.以放射免疫法测定血浆c-AMP浓度.以葡萄糖氧化酶法测定血糖浓度.结果肝硬化各组与对照组比较,基础血浆c-AMP浓度均显著高于对照组,而基础血糖无显著差异.胰高糖素负荷后5min血浆c-AMP浓度即明显增高,于10~15min达高峰,多数达峰时间在10min;血糖于5min开始升高,15~30min达高峰,多数达峰时间在30min,肝硬化各组的血c-AMP及血糖反应曲线均低于对照组,且肝硬化严重程度愈重,血c-AMP及血糖反应曲线愈低,峰值血浆c-AMP及峰值血糖浓度,肝硬化总体(122.08±84.39pmol/ml,5.71±0.75mmol/LA级(148.07±85.08pmol/ml,6.25±0.48mmol/L)、B级(120.47±173.34pmol/ml,5.84±0.60mmol/L)及C级(83.04±50.96pmol/ml,5.11±0.67mmol/L)均显著低于对照组(219.47±173.34pmol/ml,7.28±0.89mmol/L),且随肝硬化严重程度增加而显著降低.结论肝硬化患者对胰高糖负荷的血c-AMP及血糖反应能力减弱,且随肝硬化严重程度增加而减弱.  相似文献   
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