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101.
Immunity is believed to share limited resources with other physiological functions and this may partly account for the fitness costs of reproduction. Previous studies have shown that the acquired immunity of female common eiders (Somateria mollissima) is suppressed during the incubation fast. To save energy, triiodothyronine (T(3)) is adaptively decreased during fasting in most bird species, despite T(3) levels are maintained throughout incubation in female eiders. However, the relationship between thyroid hormones and the immune system is not fully understood. The current study aimed to determine the endocrine mechanisms that underlie immunosuppression in incubating female eiders. To this end we assessed the effects of exogenous T(3) on both components of the acquired immune system in 42 free-ranging incubating birds. Half of the females were implanted with T(3) pellets, while the other half sham implanted served as control. We measured variations in the immunoglobulin index, the T-cell-mediated immune response, body mass, and plasma parameters in both groups before and after manipulation. T(3) levels in implanted females were four times higher and mass loss was 40% greater than in control females. Implanted females also showed an 18% decrease in the immunoglobulin index, while the T-cell-mediated immune response was not significantly affected by the treatment. Finally, the treatment did not induce any significant changes in corticosterone levels. Our study shows that exogenous T(3) decreased only one component of the acquired immune system. We suggest that the immunosuppressive effect of T(3) could be mediated by its effects on body fat reserves. Further experiments are required to determine: (1) the relationship between adiposity and immune function, (2) the adaptive significance of immunosuppression during incubation in eiders. 相似文献
102.
Bo S Bertino E Trapani A Bagna R De Michieli F Gambino R Ghione F Fabris C Pagano GF 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2007,17(10):741-747
AimsTo evaluate cross-sectional associations between dietary magnesium intake and the metabolic pattern of very-low-birth-weight (VLBW, <1500 g) pre-term children, in pre-school years (>2 and < 6 years).Methods and resultsFifty-eight Italian children without major congenital malformations/conditions were enrolled; dietary intakes, clinical and (in 34 cases) laboratory characteristics were evaluated. Subjects with lower magnesium intake showed significantly higher fasting glucose, insulin and Homeostasis Model Assessment-Insulin Resistance (HOMA-IR) levels. At simple regression analysis, fasting glucose was significantly associated with magnesium intake (inversely) and catch-up growth (CUG). Fasting insulin and HOMA-IR values were inversely associated with intakes of magnesium and fibres, and directly with Body Mass Index (BMI) and CUG. In a multiple regression model, after adjusting for multiple confounders and fibre intake, magnesium intake was inversely associated with glucose (β = − 0.018; 95%CI −0.026 to −0.010), but not with insulin or HOMA-IR levels. In the same model, dietary fibres remained inversely associated with insulin (β = − 0.075; −0.14 to −0.008) and HOMA-IR levels (β = − 0.06; −0.11 to −0.01).ConclusionThese results suggest a significant association between reduced magnesium intake and fasting glucose, and between reduced fibre intake and insulin resistance and this is present even in earlier childhood, and independently of BMI and growth characteristics. 相似文献
103.
Petteri Nieminen Kirsti Rouvinen-Watt Lora Harris 《General and comparative endocrinology》2010,168(3):307-311
Adiponectin is a novel adipocyte-derived hormone with low circulating concentrations and/or mRNA expression in obesity and non-alcoholic fatty liver disease (NAFLD). The adiponectin mRNA of several Carnivora species was sequenced to enable further gene expression studies in this clade with potential experimental species to examine the connections of hypoadiponectinemia to hepatic lipidosis. In addition, adiponectin mRNA expression was studied in the retroperitoneal fat of the American mink (Neovison vison), as hepatic lipidosis with close similarities to NAFLD can be rapidly induced to the species by fasting. The mRNA expression was determined after overnight-7 d of food deprivation and 28 d of re-feeding and correlated to the liver fat %. The homologies between the determined carnivoran mRNA sequences and that of the domestic dog were 92.2-99.1%. As the mRNA expression was not affected by short-term fasting and did not correlate with the liver fat %, there seems to be no clear connection between adiponectin and the development of lipidosis in the American mink. In the future, the obtained sequences can be utilized in further studies of adiponectin expression in comparative endocrinology. 相似文献
104.
北京地区体检人群血糖异常发生率及其相关因素分析 总被引:2,自引:0,他引:2
目的:调查北京地区18岁以上体检人群空腹血糖(FPG)水平,分析其相关因素.方法:将38 462人在我院体检中心接受体检的人群按照不同年龄段分为八组,测定FPG水平,分析其与年龄、性别和体质指数(BMI)的关系.结果:受检人群中,超重发生率为36.4%,肥胖发生率为13.5%.FPG受损(FPG为6.1~7.0 mmol/L)率为3.2%,糖尿病(FPG≥7.0 mmol/L)发生率为3.8%.血糖异常比率随年龄的升高而逐渐增加.在20~60岁受检人群中,女性血糖水平明显低于男性(P≤0.000).FPG受损和糖尿病的发生率均随BMI升高而增加.肥胖、超重人群血糖异常发生率明显高于消瘦和正常人群(P<0.05).结论:北京地区18岁以上体检人群血糖异常的发生率与性别、年龄和BMI明显相关. 相似文献
105.
95例急性脑卒中患者空腹血糖水平与预后分析 总被引:1,自引:0,他引:1
目的检测急性脑卒中患者空腹血糖值,探讨其临床意义,以积累经验,指导临床工作。方法收集本院诊治的95例脑卒中患者的临床资料,检测其空腹血糖的表达,分析其在不同临床特征及不同预后中表达的意义。结果急性脑卒中患者的空腹血糖值为(12.22±6.02)mmol/L,明显高于正常值,重型脑卒中患者的空腹血糖的值(13.80±4.68mmol/1)明屁高于轻、中型组(10.91±6.71)mmol/L,脑卒中死亡组患者空腹血糖的值(15.48±4.97)mmol/L明显高于存活组(11.31±5.99)mmol/L。结论急性脑卒中时空腹血糖值升高,可能与判断患者预后有关。 相似文献
106.
目的 探讨早孕期空腹血浆血糖(fasting plasma glucose,FPG)与妊娠期糖代谢异常的相关性.方法 选取2009年1月1日至2009年5月31日在北京大学第一医院妇产科产前保健及分娩的单胎非孕前糖尿病且早孕期5~13周检测FPG、资料齐全的孕妇656例,对其早孕期FPG孕24周后50 g葡萄糖负荷试验结果(glucose challenge test,GCT)、75 g葡萄糖耐量试验结果(oral glucose tolerance test,OGTT)、妊娠期糖尿病(gestational diabetes mellitus,GDM)和妊娠期糖耐量受损(gestational impaired glucose tolerance,GIGT)发病情况进行受试者工作特性(receiver operating characteristic,ROC)分析.结果 (1)早孕期FPG与孕24周后GCT的ROC分析:最大曲线下面积0.539,95%CI:0.493~0.586,两者无明显相关性(P=0.057).(2)早孕期FPG与孕24周后FPG异常的ROC分析:最大曲线下面积0.796(95%CI:0.672~0.920),如取5.05 mmol/L为界值,敏感性为54.5%,特异性为83.2%,两者存在相关性(r=0.432,P=0.000).(3)早孕期FPG与孕24周后OGTT 1、2、3 h血糖无相关性(r=0.093、0.036和0.107,P=0.122、0.549和0.074),OGTT服糖前与服糖后1、2、3 h血糖分别呈正相关(r=0.493、0.421和0.368,P均=0.000).(4)本研究中共656例早孕期孕妇的FPG值均<6.1 mmol/L,诊断GDM 22例,GIGT 27例,早孕期FPG对预测最终发生GDM及GIGT无相关性.结论 早孕期FPG不能取代现有的50 g GCT作为孕期糖代谢异常的早期筛查指标,但早孕期FPG的检测是必要的.Abstract: Objective To investigate the relationship between early pregnancy fasting plasma glucose (FPG) and gestational glucose metabolism disorders. Methods Six hundred and fifty-six pregnant women who were singleton, non-diabetes before pregnancy and had FPG examined during 5-13 weeks of pregnancy were admitted into this study from January 1, 2009 to May 31, 2009. All these subjects had routine prenatal examination and finally delivered in the Department of Obstetrics of Peking University First Hospital. The FPG, 50 g glucose challenge test (GCT) after 24 weeks of pregnancy, 75 g oral glucose tolerance test (OGTT), gestational diabetes mellitus (GDM),gestational impaired glucose tolerance (GIGT) were analyzed with receiver operating characteristic (ROC) curve. Results (1) Relationship between FPG and GCT were analyzed with ROC curve.The maximum area under curve was 0. 539 (95% CI: 0. 493-0. 586) and there was no correlation between the FPG and GCT results(P=0. 057). (2) Relationship between early pregnancy FPG and abnormal FPG examined after 24 gestational weeks were also analyzed . The maximum area under curve was 0. 796(95% CI: 0. 672-0. 920). If 5. 05 mmol/L was taken as the cutoff value, the sensitivity and specificity was 54. 5% and 83. 2%, respectively. There was significant relationship between the two values (r=0. 432, P=0. 000). (3) There were no relationship between early pregnancy FPG and the blood glucose value of 1, 2 and 3 h in 75 g OGTT (r=0. 093, 0. 036 and 0. 107, P=0.122, 0. 549 and 0. 074 respectively). OGTT 0 h value was positively related to OGTT 1, 2 and3 h glucose level (r=0.493, 0.421 and 0.368, P=0.000, respectively). (4) All early pregnant FPG values in this study were under 6.1 mmol/L. Twenty-two GDM and 27 GIGT patients were diagnosed in this study. Early pregnancy FPG did not relate to the GDM and GIGT diagnosis.Conclusions Early pregnancy FPG could not replace 50 g GCT as an early screening for glucose metabolic abnormality in pregnancy, but FPG during early pregnancy is necessary. 相似文献
107.
In the rat, 1 week of a calcium-deficient diet will recruit large numbers of osteoclasts to long bone endosteal surfaces. Subsequent calcium supplementation causes the osteoclasts to disappear in 1–3 days but as little as 3 hours of calcium supplementation reduces the extent of their ruffled borders. To test the hypothesis that at some point there is an irreversible inhibition of osteoclasts, male, weanling, calcium-deficient, SD rats were given various amounts of calcium-containing diet followed by a 12-hour fast. No changes in seven morphological indices of osteoclast activity were found. The hypothesis that the fast had reversed the effects of the calcium diet was supported by a second experiment indicating that no inhibition threshold had been reached. Another experiment showed differences in the degree of osteoclast inhibition with different amounts of calcium supplementation, again without evidence of a threshold. These experiments raised two questions: (1) Will fasting recruit osteoclasts in calcium-replete rats? and (2) Is osteoclast recruitment facilitated by the presence of postosteoclasts? The results of experiments testing these hypotheses support the conclusion that fasting and calcium deficiency maintain plasma calcium levels by different mechanisms, and post-osteoclasts are not available for reactivation. It is concluded that inhibition of osteoclasts by dietary calcium is a graded phenomenon, and when osteoclasts have lost contact with the bone surface they are unavailable for reactivation; a threshold has been reached. 相似文献
108.
Many regulatory toxicity guidelines and the recommendation of AACC-DACC/ASVCP joint task force of the USA on clinical pathology testing require overnight fasting for rats and non-rodents before blood sampling. However, the reason why animals must be fasted before blood sampling is unclear in toxicology studies.Fasting, one of many preanalytical conditions, can lead to false low or high values, which in turn may lead to misinterpretation of test compound effects in toxicological studies. This paper reviews the literature with respect to fasting, and reports on our own studies, in the hope of increasing the awareness among investigators of these problems.Haematocrit values and plasma chemistry values in blood obtained from rats and dogs following fasting were compared with unfasted animals. In male F344 rats, after 16 h fasting, body weight decreased. Increases in aspartate aminotransferase (AST)/glutamic oxaloacetic transaminase (GOT) and decreases of plasma alkaline phosphatase (ALP), total cholesterol (CHO), triglycerides (TG), phospholipids (PL), urea nitrogen (UN) and calcium were observed. Haematocrit, plasma alanine aminotransferase (ALT)/glutamic pyruvic transaminase (GPT), total proteins (TP), glucose, and inorganic phosphorus (IP) were unchanged. In male beagle dogs after 16 h fasting, TG, PL, UN, calcium and IP were decreased. Haematocrit, ALP, TP, albumin, glucose, CHO, creatinine, AST/GOT, ALT/GPT, LDH and CPK were not changed.Our own studies show that in order to avoid excessive stress to test animals, the fasting period should be decided case by case, and not made uniform in toxicology studies. It would be useful if regulatory guidelines made some mention of both the effect of feeding, and of stress caused by fasting. 相似文献
109.
实时超声法测定空腹胃窦面积的临床意义 总被引:1,自引:0,他引:1
本文利用实时超声法测定了58例健康人及59例胃病及糖尿病病人空腹胃窦面积。结果显示,健康中国人胃窦面积为1.52cm2±0.43cm2,与性别、年龄、身高、体重无关,胃炎、糠尿病、活动期十二指肠溃疡病人空腹胃窦面积均有不同程度扩大,慢性胃炎伴呃逆,腹胀症状及糖尿病病人异常率为100%。本文中有22例病人同时做食管测压检测,结果显示溃疡病病人空腹胃窦面积与食道上、中、下段压力均无关,糖尿病、胃炎病人胃窦面积与LESP呈负相关。此研究结果提示空腹胃窦面积可在某种程度上代表胃排空功能。 相似文献
110.
《Nutrition, metabolism, and cardiovascular diseases : NMCD》2022,32(5):1175-1185
Background and aimsThe role of diet in blood lipids is scarcely investigated in adults at risk of Type 2 Diabetes Mellitus (T2DM) and even less studied regarding their socioeconomic status (SES). This study aimed to investigate the associations of diet quality with blood lipids in adults from families at high-risk for developing T2DM from six European countries, considering their SES.Methods and resultsIn total 2049 adults (67% women) from relatively low-SES regions and high T2DM risk families were enrolled. Dietary habits, sedentary behaviour and sociodemographic characteristics were assessed using standardised questionnaires. The associations of tertiles of healthy diet score (HDS) with blood lipids were tested by univariate analysis of variance (UNIANOVA). HDL-Cholesterol (HDL-C) was positively (B 1.54 95%CI 0.08 to 2.99) and LDL-Cholesterol (LDL-C) (B ?4.15 95%CI ?7.82 to ?0.48), ratio of total cholesterol to HDL-C (B ?0.24 95%CI ?0.37 to ?0.10), ratio of LDL-C to HDL-C (B ?0.18 95%CI ?0.28 to ?0.08) and Atherogenic Index of Plasma (B ?0.03 95%CI ?0.06 to 0.00) inversely associated with the highest tertile of diet score compared to the lowest tertile independently of age, sex, Body Mass Index, total screen time and smoking. In sub-analysis of education (<14 and ≥ 14 years of education), these findings were only significant in the high-SES group.ConclusionWhile diet quality was poorer in the low-SES group, an association between diet quality and lipidemic profile was not found, as increased central obesity and smoking prevalence might have confounded this association. These findings indicate the need for tailor-made interventions, guided by the specific risk factors identified per population sub groups. 相似文献