Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Fructosamine”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,405 records · Page 78Linked to original sources
PubMed2000

The impaired renal vasodilator response attributed to endothelium-derived hyperpolarizing factor in streptozotocin--induced diabetic rats is restored by 5-methyltetrahydrofolate.

AIMS/HYPOTHESIS: Endothelial dysfunction contributes to the development of diabetic vascular complications. A better understanding of the pathophysiology of endothelial dysfunction in diabetes could lead to new approaches to prevent microvascular disease. METHODS: Endothelium-dependent and endothelium-independent vasodilator responses were investigated in the renal microcirculation of streptozotocin-induced diabetic rats. We measured renal blood flow changes with an electromagnetic flow probe. In addition, the responses of the different segments of the renal microcirculation were evaluated with videomicroscopy using the hydronephrotic kidney technique. Because endothelial cells release different relaxing factors (nitric oxide, prostacyclin and an unidentified endothelium-derived hyperpolarizing factor), responses to acetylcholine were measured before and after treatment with the nitric oxide synthase inhibitor L-NG-nitroarginine methylester HCI (L-NAME) and the cyclooxygenase inhibitor indomethacin. We evaluated with the effect of 5-methyltetrahydrofolate, the active form of folate, on the responses. RESULTS: The L-NAME- and indomethacin-resistant vasodilation to intra-renal acetylcholine was significantly reduced in the diabetic compared with control rats, suggesting impaired endothelium-derived hyperpolarizing factor-mediated vasodilation. The responses to the nitric oxide donor (Z)-1-[-2-(aminoethyl)-N-(2-ammonioethyl)amino]diazen-1-i um-1,2-diolate (DETA-NONOate) and to the K+-channel opener pinacidil were similar in diabetics and controls, indicating intact endothelium-independent vasodilator mechanisms. The contribution of endothelium-derived hyperpolarizing factor to vasodilation induced by acetylcholine was greatest in the smallest arterioles. In diabetic rats, the response to acetylcholine was increasingly impared as vessel size decreased. Defective vasodilation in diabetic kidneys was rapidly normalized by 5-methyltetrahydrofolate. CONCLUSION-INTERPRETATION: Endothelium-derived hyperpolarizing factor-mediated vasodilation is impaired in the renal microcirculation of diabetic rats, in particular in the smallest arteries. Treatment with folate restores the impaired endothelial function in diabetes.

Acetylcholine↗
PubMed2003

A phytosterol-enriched spread improves the lipid profile of subjects with type 2 diabetes mellitus--a randomized controlled trial under free-living conditions.

BACKGROUND: Phytosterol-enriched margarines are known to significantly lower total and LDL cholesterol, but little is known about the effect of such margarines in subjects with type 2 diabetes. AIM OF THE STUDY: Investigation of the effect of a phytosterol-enriched spread in subjects with type 2 diabetes mellitus on serum lipids, Hb(A1c), and blood glucose under free-living conditions. METHODS: Randomized, placebo-controlled, double-blind clinical trial in two parallel groups over 12 weeks; 85 type 2 diabetic patients with serum LDL cholesterol levels >/= 3.60 mmol/l and without hypolipidemic medication were included in the study. Participants consumed 2 x 10 g of spread with or without 8 % phytosterol-esters daily. Fasting blood samples were analyzed at 0, 4, 8, and 12 weeks. RESULTS: After 4 weeks, total and LDL cholesterol were significantly reduced in the phytosterol group by 5.2 % and 6.8 %, respectively, compared to baseline (p < 0.05). After 8 and 12 weeks, these reductions became smaller and were not significant any more compared to baseline or between the groups, but a repeated measurement analysis demonstrated a significant difference for both variables between the two groups (each p < 0.05). HDL cholesterol was significantly increased in the phytosterol group compared to the placebo group after 8 and 12 weeks, but there was no overall difference in the repeated measurement analysis between the two groups. In the phytosterol group, there was a small reduction in Hb(A1c) compared to the control group which was only significant after 4 weeks. CONCLUSIONS: This clinical study shows that a phytosterol-enriched spread is effective in lowering total and LDL cholesterol in subjects with type 2 diabetes but also illustrates the difficult maintenance under free-living conditions over time. Although this effect is modest, it may contribute to decreasing the elevated risk of cardiovascular disease in type 2 diabetes.

Blood Glucose↗
PubMed2000

Evaluation of T-cell receptor CD3+ gamma delta in gestational diabetes mellitus.

Few studies have shown a significant increase of CD3+ T-cell receptor (TCR) gamma delta in the early phases of type 1 diabetes. We wished to determine if CD3+ TCR gamma delta is involved in the pathogenesis of gestational diabetes mellitus (GDM). We studied 29 GDM patients and 21 normal pregnant women. Lymphocyte subpopulations (CD3+ TCR alpha beta, CD3+ TCR gamma delta), islet cell antibodies (ICA), glutamic acid decarboxylase antibodies (GAD) and protein tyrosine phosphatase antibodies (IA2-Ab) were evaluated in all patients. The percentage of CD3+ TCR gamma delta was significantly higher in GDM women than in the control group (5.1 +/- 2.9% vs 3.7 +/- 1.7%; p < 0.05). No abnormalities of the other lymphocyte subpopulations were found. All subjects were negative for ICA; 2 GDM patients were positive for GAD, but no relationship was found between GAD positivity and CD3+ gamma delta levels in these 2 patients. Further follow-up studies of these patients are required to verify if the CD3+ TCR gamma delta receptor is a useful marker for diabetes development.

Adult↗
PubMed1984

Optimal conditions for 4-hydroxybenzoyl- and 2-furoylhydrazine as reagents for the determination of carbohydrates, including ketosamines.

4- Hydroxybenzoylhydrazine ( PAHBAH ) reacts with glucose in hot aqueous solution when alkali exceeds aroylhydrazine concentration. The related 2- furoylhydrazine ( FAH ) reacts at lower alkali concentrations, making this an attractive alternative carbohydrate reagent since it is (unlike PAHBAH ) freely water soluble. FAH reacts with monosaccharides more slowly than does PAHBAH , giving about half the color. Its specificity and behavior with a bismuth catalyst parallel those of PAHBAH . Solutions which contain 0.05 mol/liter PAHBAH with 1.5 mmol/liter bismuth III (as tartrate complex) and 0.5 mol/liter sodium hydroxide, or 0.01 mol/liter FAH with 1.5 mmol/liter bismuth III and 0.1 mol/liter sodium hydroxide are sensitive reagents for quantitative analysis, giving stable colors with many carbohydrates within 10 min at 75 degrees C. Ketosamines react more rapidly than glucose at lower temperatures and undergo similar reactions in less alkaline solutions. At pH less than 8, the reaction is specific for these 1- aminohexoses , and FAH can be used as a reagent for their assay.

Autoanalysis↗
PubMed1985

Glycosylation of nail in diabetics: possible marker of long-term hyperglycemia.

Fingernail samples from 32 patients with diabetes mellitus and from 26 non-diabetics were analyzed in order to determine the protein glycosylation rate in nail. Nail glycosylation was assayed by the thiobarbituric acid reaction. Blood was taken from both diabetics and non-diabetics at the same time for measurement of hemoglobin glycosylation. In non-diabetics, the protein glycosylation in nail and glycosylated hemoglobin were found to be 8.35 +/- 2.7 nmol fructosamine/mg nail and 2.24 +/- 0.45 mumol fructosamine/g hemoglobin, respectively. In diabetics, however, there was an extremely high glycosylation in both nail protein and hemoglobin: 16.0 +/- 7.35 nmol fructosamine/mg nail and 5.17 +/- 1.17 mumol fructosamine/g hemoglobin (p less than 0.001 for both). A significant correlation was found between nail glycosylation and glycosylated hemoglobin in diabetics (r = 0.923, p less than 0.001). Also, there was a correlation between diabetic fasting blood glucose and protein glycosylation in nail (r = 0.947, p less than 0.001). Our findings show that it might be useful in the investigation of microvascular complications of diabetes mellitus to evaluate the possibility of nail glycosylation providing a stable long-term measure of tissue glycosylation.

Adolescent↗
PubMed1992

Polyclonal immunoglobulin M: location of glycation sites.

A four step purification procedure for polyclonal human serum IgM was elaborated, including ultracentrifugation, ammonium sulfate and polyethyleneglycol precipitations and diffusion-exclusion gel chromatography. IgM was glycated in vitro both in the presence of [14C]glucose and with unlabeled glucose. Influence of incubation time up to 10 days and of glucose concentration between 10 and 60 mmol/l were studied. With 10 mmol/l glucose, a molar ratio glucose/IgM of 5.7 was attained in 10 days. Increase of glucose concentration up to 60 mmol/l led to a molar ratio of 16.0. Both basal and in vitro glycation were evaluated by 3H-labeling by gel filtration and Concanavalin A-Sepharose chromatographies. Glycation occurs mainly on the heavy chains (> 85%), particularly on the Fd region.

Binding Sites↗
PubMed1992

An oxidative mechanism is involved in high glucose-induced serum protein modification causing inhibition of endothelial cell proliferation.

In order to investigate the role of hyperglycemia on the development of atherosclerosis in diabetics, the effects of high glucose-induced modification of serum factors on the proliferation of bovine carotid artery endothelial cells were studied. Dialysates of high glucose-treated serum inhibit cell growth in a time- and glucose concentration-dependent manner. With 6 weeks of pretreatment, 16.7 mM glucose causes a 47.2% inhibition in cell growth compared to 5.6 mM glucose (P < 0.001). Pretreatment of serum in the presence of reduced glutathione (0.5-1.0 mM), an antioxidant, significantly prevents the high glucose-induced inhibition without inhibiting the formation of early non-enzymatic glycosylation products. Dithiothreitol (7.5 mM) treatment after preincubation with glucose fully restores the glucose-induced inhibition. When the dialysates are fractionated according to molecular mass, the high glucose-induced inhibition is maximal in the MW fraction above 100 kDa. These data suggest that high glucose conditions facilitate the susceptibility of serum proteins to sulfhydryl oxidation forming disulfide crosslinks and this oxidative process may contribute to the inhibition of endothelial cell proliferation.

Animals↗
PubMed1990

New criteria for interpretation of the 75 g oral glucose tolerance test in pregnancy.

A 75 g oral glucose tolerance test (OGTT) was performed on 135 high-risk pregnant patients. When the current World Health Organization (WHO) criteria for the diagnosis of gestational-glucose tolerance were applied, 88 patients were considered normal, 11 had gestational diabetes, and 36 patients had impaired-glucose tolerance, respectively. The plasma glucose, insulin, and C-peptide levels during the OGTT were further studied in the 88 patients (who had normal results). Two metabolically distinct groups were identified; a group (n = 53) with a 2-hour plasma glucose less than or equal to 6.6 mmol/L (118.8 mg/dL), had a normal insulin and C-peptide pattern, and a second group (n = 35) who had 2-hour plasma glucose greater than 6.6 mmol/L displayed a glycemic, insulin, and C-peptide pattern similar to that of patients with gestational diabetes mellitus. The risks of macrosomic babies and operative delivery were significantly greater in the latter group. These results suggest that in our pregnant population, a group of patients with impaired glucose tolerance will be under-diagnosed using the current WHO criteria. Based on our results new criteria for gestational glucose intolerance are suggested for our population.

Administration, Oral↗
PubMed1992

Increased in vivo production of tumor necrosis factor after development of diabetes in nontreated, long-term diabetic BB rats.

We have recently reported that chronic and systemic administration of tumor necrosis factor alpha (TNF) inhibits development of autoimmune diabetes in NOD mice and BB rats, animal models of insulin-dependent diabetes mellitus (IDDM). During these experiments, we unexpectedly found that in vivo production of TNF stimulated by a single injection of lipopolysaccharide was enhanced approximately 10 times in the long-term diabetic BB rats (P less than 0.0001), whose mean duration of diabetes with more than 16.8 mM (300 mg/dl) of nonfasting blood glucose level was 26.2 +/- 2.1 days, as compared to that in the rats of nondiabetes and in the rats at the onset of diabetes, whose mean duration of diabetes was 1.4 +/- 0.6 days. The long-term diabetic, but not short-term-diabetic, rats were also associated with increased levels of serum fructosamine/albumin (P less than 0.01) and triglyceride (P less than 0.01) and with a decreased level of serum albumin (P less than 0.01). The in vivo TNF productivity in the diabetic rats, including the short-term- and long-term-diabetic rats, was correlated positively with the level of fructosamine/albumin (P less than 0.05) and negatively with the level of serum albumin (P less than 0.05), but not with levels of blood glucose. None of these correlations were observed in nondiabetic rats. The increased LPS-induced serum TNF activity in the long-term diabetic state was observed not only in BB rats but also in NOD mice and GK rats, a model of non-IDDM, irrespective of sexes and ages, indicating that the enhancement of in vivo TNF production was a result of long-term diabetes. These findings indicate that some factor(s) associated with the long-term-diabetic state may prime macrophages in vivo to produce TNF. Further study is needed to reveal a mechanism of the enhanced TNF production and its possible relevance to various abnormalities associated with the chronic hyperglycemic state.

Age Factors↗
PubMed1986

Sequence-specific alkali-labile lesions in DNA caused by D-isoglucosamine.

The site-specific induction of DNA damage by 1-amino-1-deoxy-D-fructose (D-isoglucosamine) was investigated. When 32P-end-labeled DNA restriction fragments of known sequence were reacted with D-isoglucosamine in the presence of Cu2+, and the DNA products were analyzed on high-resolution denaturing polyacrylamide gels after treatment with aqueous piperidine (1 M) at 90 degrees C for 30 min, the DNA strands were cleaved at pyrimidine residues at a statistically significant frequency, and 80.5% of the extensively damaged sites were induced at pyrimidine residues in dinucleotide sequences of pyrimidine-purine (5'----3'). These cleavages were scarcely observed without piperidine/heat treatment. The damaged DNA sites increased in proportion to the reaction time and concentration of D-isoglucosamine. Metal-chelating agents (EDTA, diethylenetriaminepentaacetic acid) and some oxygen radical scavengers inhibited the induction of alkali-labile lesions. These results indicate that some oxygen radicals are involved in the induction of alkali-labile lesions.

Base Sequence↗
PubMed1991

Clinical characteristics and management of diabetic patients residing in a nursing home.

In 38 diabetic patients, admitted on a long-term basis to a nursing home, the clinical situation and presence of secondary diabetic complications were assessed, and their macrovascular complications and degree of glycemic control compared with those in ambulatory diabetic patients, matched for age, sex, known duration of diabetes and specific antidiabetic therapy. No differences in blood glucose control, plasma triglycerides, blood pressure and serum creatinine were observed between both groups of patients. Plasma cholesterol levels were higher in the ambulatory patients (6.4 +/- 1.0 vs 5.6 +/- 1.1 mmol/l, P = 0.008). Twenty-two nursing home patients had suffered from stroke, against 4 ambulatory patients. Hypertension was found in almost 50% of all patients, whereas its prevalence was highest in the stroke patients (69 vs 36%, P less than 0.01). In the nursing home patients, peripheral vascular abnormalities, skin necrosis or leg ulcers and recurrent urinary tract infections were frequently encountered, whereas in the ambulatory patients cardiac complaints were more prevalent. Use of medication, especially diuretics and anticoagulant agents, was higher in the nursing home patients. Diabetes and the sequelae of its macrovascular complications may greatly impair the quality of life of the diabetic patient, and place a large financial and personal burden on the health care in general. Better identification of diabetic patients with a high risk of stroke is necessary.

Aged↗
PubMed1992

Effect of disease duration on cardiac autonomic reflexes in young patients with insulin-dependent diabetes mellitus.

The association of disease duration with deterioration of cardiovascular autonomic reflexes was studied in two groups of young patients with insulin-dependent diabetes mellitus (IDDM). The mean age of the patients in both groups was 31 years and the mean duration of the disease was 3 (n = 18) and 16 (n = 22) years. No significant difference in group means was seen in the test parameters of autonomic nerve function. However, five patients with long-term disease, but none with short-term disease, had test scores indicating cardiac autonomic neuropathy. It was concluded that (1) the duration of the disease has no overall effect on autonomic nerve function in young patients with IDDM, but (2) a few individuals with IDDM may have some precipitating factors leading to autonomic neuropathy in the course of the disease.

Adult↗
PubMedDate not supplied

An examination of the covariability of subclinical albuminuria in insulin-dependent diabetes mellitus: implications for monitoring microalbuminuria.

We examined the covariability of subclinical albuminuria in a cohort of 160 insulin-dependent diabetics who underwent simultaneous measurements of overnight urinary albumin excretion rate (UAV) and several clinical variables on 7 occasions over a period of 18 months. After allowing for within-patient correlation between visits, significant within-patient associations were found between UAV and variations in tobacco consumption (regression coefficient = 0.006, S.E. = 0.002, P = 0.02), insulin dose (regression coefficient = 0.003, S.E. = 0.001, P = 0.01) and creatinine clearance (regression coefficient = 0.776, S.E. = 0.047, P < 0.0001); the association between UAV and creatinine clearance was not influenced by adjusting for urine flow rate. No significant associations were found between UAV and changes in blood pressure, glycaemic control or other variables. We then focused on 33 patients with intermittent microalbuminuria, defined as a UAV > 30 micrograms/min on at least one occasion, but not exceeding 3 consecutive occasions. These patients had a total of 52 episodes of microalbuminuria which were significantly associated at the 5% level with increases in creatinine clearance (P = 0.02), but not with changes in other variables. Our findings did not differ in patients with intermittent microalbuminuria defined with reference to a cut-off UAV of 20 micrograms/min. We conclude that changes in glomerular filtration rate (as reflected by creatinine clearance) may partly account for the within-patient variability in subclinical albuminuria in insulin-dependent diabetics, and that variables routinely measured in the clinic are not useful for deciding when to monitor patients for microalbuminuria.

Adolescent↗