Home About us Contact
|
Home About us Contact | ||
|
|
||
Glucose Alone (glucose + alone)
Selected AbstractsPlasma Hypertonicity: Another Marker of Frailty?JOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 8 2004Jodi D. Stookey PhD Objectives: To determine whether plasma hypertonicity might be a marker of early frailty, this study tested the associations between plasma hypertonicity, incident disability, and mortality in nondisabled older adults. Design: Longitudinal, observational study. Setting: Community-based. Participants: Older adults (,70), who reported no disability and gave blood in the 1992 Duke Established Populations for Epidemiologic Studies of the Elderly survey (n=705), were re-interviewed in 1996 for functional status (n=561) and followed for all deaths up to January 1, 2000. Measurements: Plasma tonicity was estimated from plasma glucose, sodium, and potassium measures and used to classify subjects as normo- (285,294 mOsm/L) or hypertonic (,300 mOsm/L). Disability was defined as any impairment on the Rosow-Breslau, activity of daily living (ADL), and instrumental activity of daily living (IADL) scales. The relative risk (RR) of any new disability and relative hazard of death associated with hypertonicity were estimated using logistic regression models and Cox proportional hazards models, respectively. All models were controlled for age, sex, race, weight status, current smoking, activity level, plasma blood urea nitrogen and creatinine, cognitive impairment, depression, and chronic disease status. To determine whether observed effects were attributable to plasma glucose alone, all models were repeated on a subsample of nondiabetic, normoglycemic subjects. Results: Plasma hypertonicity (observed in 15% of subjects) was associated with increased risk of new Rosow-Breslau (RR=2.1, 95% confidence interval (CI)=1.2,3.6), IADL (RR=2.3, 95% CI=1.2,4.3), and ADL (RR=2.7 95% CI=1.3,5.6) disability by 1996 and mortality by 2000 (RR=1.4, 95% CI=1.0,1.9). Results were similar for the normoglycemic subgroup (ADL: RR=2.9, 95% CI=1.0,8.0; IADL: RR=2.5, 95% CI=1.0,6.3; Rosow-Breslau: RR=1.8, 95% CI=0.8,3.9; mortality: RR=1.5, 95% CI=0.9,2.3). Conclusion: Plasma hypertonicity may be a marker of early frailty. It was prevalent in this sample of nondisabled community-dwelling older adults and predicted incident disability and mortality. Further research to identify its determinants and consequences may help inform interventions against frailty. [source] Changes in oxidative balance in rat pericytes exposed to diabetic conditionsJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 1 2004A. Manea Abstract Recent data indicate that the oxidative stress plays an important role in the pathogenesis of diabetes and its complications such as retinopathy, nephropathy and accelerated atherosclerosis. In diabetic retinopathy, it was demonstrated a selective loss of pericytes accompanied by capillary basement membrane thickening, increased permeability and neovascularization. This study was designed to investigate the role of diabetic conditions such as high glucose, AGE-Lysine, and angiotensin II in the modulation of antioxidant enzymes activities, glutathione level and reactive oxygen species (ROS) production in pericytes. The activity of antioxidant enzymes: superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and total glutathione (GSH) was measured spectrophotometrically. The production of ROS was detected by spectrofluorimetry and fluorescence microscopy after loading the cells with 2,-7, dichlorofluoresceine diacetate; as positive control H2O2 was used. Intracellular calcium was determined using Fura 2 AM assay. The results showed that the cells cultured in high glucose alone, do not exhibit major changes in the antioxidant enzyme activities. The presence of AGE-Lys or Ang II induced the increase of SOD activity. Their combination decreased significantly GPx activity and GSH level. Athree times increase in ROS production and a significant impairment of intracellular calcium homeostasis was detected in cells cultured in the presence of the three pro-diabetic agents used. In conclusion, our data indicate that diabetic conditions induce in pericytes: (i) an increase of ROS and SOD activity, (ii) a decrease in GPx activity and GSH level, (iii) a major perturbation of the intracellular calcium homeostasis. The data may explain the structural and functional abnormalities of pericytes characteristic for diabetic retinopathy. [source] Hyperglycemia Stimulates a Sustained Increase in Hydraulic Conductivity In Vivo without Any Change in Reflection CoefficientMICROCIRCULATION, Issue 7 2007RACHEL M. PERRIN ABSTRACT Objective: Increased microvascular permeability contributes to the development of diabetic microvascular complications and diabetic vasculopathy is correlated with blood glucose levels. The mechanisms underlying increased permeability, however, are poorly understood. Methods: The Landis-Michel technique was used to measure water permeability (hydraulic conductivity, Lp) and macromolecular permeability (reflection coefficient, ,) of exchange capillaries in frogs and rats. Results: Dialysed normoglycemic plasma from diabetic patients had no effect on Lp. The same plasma with 20 mM glucose increased hydraulic conductivity from (mean ± SEM × 10,7 cm · s,1· cm H2O,1) 5.73 ± 2.01 to 13.09 ± 2.67 (P < .01). Nondiabetic control plasma did not affect Lp, but addition of 20 mM glucose increased Lp to a similar degree. The effect of glucose alone was examined. Glucose at 20 mM increased Lp, from 2.82 ± 0.61 to 4.71 ± 1.35 × 10, 7 cm · s, 1· cm H2O,1 (P = .002, n = 13). A similar increase was seen in rat mesenteric microvessels, from 1.04 ± 0.40 in control perfusions to 2.18 ± 0.56, P < .05. The microvascular macromolecular reflection coefficient in all the above experiments was unaltered. The use of specific inhibitors indicated that the glucose-induced increased Lp did not appear to be mediated through protein kinase C (PKC), free radical generation, glucose metabolism, or albumin glycation. Conclusions: These data suggest that hyperglycemia induced increased apparent protein permeability may be secondary to a glucose-mediated change in macromolecular convective flux rather than any change in protein permeability per se. The authors speculate that the increased microvascular permeability to water in vivo is mediated by direct interaction of glucose with the endothelial cells (perhaps with the glycocalyx). [source] Fasting capillary glucose as a screening test for gestational diabetes mellitusBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 9 2006H Fadl Objective, To evaluate fasting capillary glucose as a screening test for gestational diabetes mellitus (GDM) compared with traditional risk factors and repeated random capillary glucose measurements. Design, Cross-sectional, population-based study. Setting, Maternal Health Care Clinics in Örebro County, Sweden. Population, An unselected population of women without diabetes. Methods, Fasting capillary glucose levels were measured at gestational weeks 28,32. Random capillary glucose levels were measured four to six times during pregnancy. Traditional risk factors for GDM were registered. GDM was diagnosed using a 75-g oral glucose tolerance test. Main outcome measures, Sensitivity, specificity, likelihood ratios. Results, In 55 of 3616 women participating in the study, GDM was diagnosed before 34 weeks of gestation. For fasting capillary glucose cutoff values between 4.0 and 5.0 mmol/l, sensitivity was in the range between 87 and 47% and specificity between 51 and 96%. Using a combined screening model of traditional risk factors with fasting capillary glucose at various cutoff values increased the sensitivity only slightly compared with using fasting capillary glucose alone. Conclusion, In this Swedish, unselected, low-risk population, fasting capillary glucose measurements were found to be an acceptable and useful screening test for GDM. [source] | ||||||||||