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Biomedical subjects

I De Leeuw

Publications and source records attributed to I De Leeuw.

At least 19 recordsLinked to original sources
PubMed2005

Effects of micronized fenofibrate and vitamin E on in vitro oxidation of lipoproteins in patients with type 1 diabetes mellitus.

OBJECTIVE: The primary objective was to compare the antioxidant activity of micronised fenofibrate 200 mg to 400 IU of vitamin E and placebo, on the LDL and VLDL particles of patients with type 1 diabetes. The secondary objective was to investigate the possible synergy between micronized fenofibrate and vitamin E and to compare the efficacy of these treatments on lipids. METHODS: A double-blind, placebo-controlled trial in which patients were randomised into three treatment groups after a wash-out period of 8 weeks: the placebo group (Pla/Pla-group) in which patients received placebo during two consecutive periods of 8 weeks, the vitamin E group (Vit E/Vit E-group) in which patients received Vitamin E during two consecutive periods, and the fenofibrate/Vitamin E group (Fen/Fen + Vit E-group) in which patients received fenofibrate during the first period, followed by fenofibrate and vitamin E during the consecutive period. Blood samples taken at each visit, were analysed for routine biochemistry, blood lipids and copper mediated lipid peroxidation in vitro. RESULTS: The lag time of the non-HDL lipoprotein oxidation increased in the group given fenofibrate. The lag-time increased further when fenofibrate and vitamin E were given in association. (This reached significance in the intention-to-treat population, P = 0.034). The AUC of TBARS formation in the Vit E/Vit E group decreased after the first period, but this effect was not enhanced by continuing vitamin E for another 8 weeks. The AUC of TBARS formation did not change significantly after the administration of fenofibrate. Only after the second period, when vit E was given in association, the AUC of TBARS formation decreased significantly (P = 0.004). Fenofibrate caused a significant decrease in total and LDL-cholesterol and triglycerides (P < 0.05). In contrast, vitamin E had no effect on lipids. CONCLUSIONS: The combination of micronized fenofibrate 200 mg/day and vitamin E 400 IU/day tended to increase the resistance of non-HDL lipoproteins to copper-mediated oxidation, shown by a prolongation of the lag-time. Vitamin E administration only, decreased the oxidation of non-HDL lipoproteins shown by a reduction of TBARS formation. This protective effect of vitamin E tended to be amplified by micronized fenofibrate.

Adult↗
PubMed2005

Insulin detemir used in basal-bolus therapy in people with type 1 diabetes is associated with a lower risk of nocturnal hypoglycaemia and less weight gain over 12 months in comparison to NPH insulin.

AIM: The aim of this study was to compare the long-term safety and efficacy of twice-daily insulin detemir or NPH insulin as the basal component of basal-bolus therapy in people with type 1 diabetes. METHODS: A multicentre, open-label, parallel-group study was conducted over 12 months and completed by 308 people (from an original randomized cohort of 428). Patients were randomized in a 2:1 ratio to receive insulin detemir or NPH insulin before breakfast and dinner, with insulin aspart at mealtimes. RESULTS: Glycaemic control improved in both groups with HbA(1c) decreasing by 0.64 and 0.56% point in the insulin detemir and NPH insulin groups, reaching baseline-adjusted final values of 7.53 +/- 0.10% and 7.59 +/- 0.13%, respectively. No significant difference was apparent between treatments in terms of HbA(1c), fasting plasma glucose or 9-point blood glucose profiles. Fewer hypoglycaemic events (major and minor) occurred in association with insulin detemir compared with NPH insulin, but the overall hypoglycaemic risk did not differ statistically significantly (RR for detemir, 0.78 [0.56-1.08]). However, the risk of nocturnal hypoglycaemia during the maintenance phase (month 2-12) was 32% lower in the detemir group (p = 0.02) and lower in every month. This risk reduction remained statistically significant after correction for HbA(1c). After 12 months, baseline-adjusted mean body weight was significantly lower in the insulin detemir group than in the NPH insulin group (p < 0.001). CONCLUSIONS: In long-term basal-bolus therapy, insulin detemir with insulin aspart as mealtime insulin is well tolerated and reduces the risks of nocturnal hypoglycaemia and weight gain compared to NPH insulin.

Adult↗
PubMed2004

Glucose evaluation trial for remission (GETREM) in type 1 diabetes: a European multicentre study.

OBJECTIVE: Strict metabolic control during the 1st year of type 1 diabetes is thought to be a key factor for achieving clinical remission. The aims of this study were two-fold: (i) to evaluate the frequency and duration of spontaneous remission (defined according to the parameters issued by the International Diabetic Immunotherapy Group (IDIG)) in a European population of consecutive recent onset type 1 diabetes patients (aged 5-35 years), followed-up for a period of 36 months with a common protocol of intensive insulin therapy and without adjunct immune-intervention; and (ii) to identify the predictive factors for clinical remission. RESEARCH DESIGN AND METHOD: A total of 189 consecutive patients with newly diagnosed type 1 diabetes according to ADA criteria were recruited in participating centres (Belgium, Czech Republic, Estonia, France, Germany, Hungary, Italy, Poland, Romania, Sweden and Turkey) and followed-up for a period of up to 36 months. In all patients, intensive insulin therapy was implemented consisting of three or four injections of regular insulin daily with NPH insulin at bedtime. Adjustment of insulin dose was made according to a common protocol. Various clinical characteristics (age, gender, severity of presentation, etc.), history (presence of diabetic siblings in the family, etc.) and integrated parameters of metabolic control (HbA(1c), blood glucose, the total insulin dose at hospital discharge adjusted for body weight) were collected. RESULTS: Twenty-two patients (11.6%) experienced remission. The median duration of remission was 9.6 months and the range was 31 months. There was a wide variation among centres. Logistic regression analysis focused on the centre as the main variable in achieving remission. CONCLUSION: Remission was shown to be very heterogeneous between centres depending on 'other factors' such as patient care and family awareness of the disease rather than on 'measurable factors' such as sex, age, HbA(1c) and severity of presentation at diagnosis. Using intensive insulin therapy and optimisation of metabolic control, remission occurred in nearly one out of eight patients.

Adolescent↗
PubMed2003

Oxidative stress status in patients with diabetes mellitus: relationship to diet.

OBJECTIVE: To investigate the relationship between dietary intakes and in vivo oxidative stress (OS) status in diabetic patients. DESIGN: Case-control study. SETTING: Outpatient-Clinic and Laboratory Endocrinology, University Antwerp. SUBJECTS AND METHODS: A total of 30 patients (24 type 1 diabetes mellitus (T1DM)/6 type 2 diabetes mellitus (T2DM) were asked to complete a 2 weekdays+1 weekend day food consumption questionnaire during the week preceding their yearly diabetes control consultation, when samples were collected for the assay of oxidative stress (OS) (blood levels of antioxidants, peroxides, malondialdehyde (MDA) and minerals). Blood samples were also collected from 25 age- and sex-matched healthy controls. RESULTS: Diabetic patients had lower glutathione (5.80+/-1.15 vs 6.75+/-1.03 micromol/g Hb in the controls, P=0.002) and higher MDA (0.687+/-0.212 vs 0.545+/-0.101 micromol/l, P=0.002). Although the group average intakes were within the Belgian RDA, intakes of fat >35% energy, fibre <15 g/1000 kcal, fruit <2 portions and vitamin E <10 mg/day were seen in more than 20 patients. Blood antioxidants did not correlate with intakes of energy, fat, protein or fibres or of their respective antioxidant. Vitamins A and E correlated with serum lipids (r=0.58, P <0.0005 between serum alpha-tocopherol and cholesterol). Blood peroxide levels were only related to intakes of saturated fat and cholesterol (P<0.05). In diabetic subjects but not in controls (P<0.05) MDA was related to glutathione and uric acid. CONCLUSIONS: In diabetic patients, blood levels of antioxidants are not related to their dietary intakes but to serum lipids. Levels of oxidative damage products are only related to intakes of saturated fats and cholesterol and to levels of endogenous antioxidants.

Adult↗
PubMed2003

Leptin levels in type 2 diabetes: associations with measures of insulin resistance and insulin secretion.

Interactions between leptin and insulin have been shown previously, in vitro and in vivo. In this study, we evaluate the associations of leptin levels with insulin secretion and insulin sensitivity in type 2 diabetes. Fasting leptin levels, HbA 1c, glucose, insulin, C-peptide, intact and des-31,32-proinsulin were measured in 100 non-insulin-treated type 2 diabetic patients. Glucose, insulin and C-peptide were measured 2 hours after an oral glucose load. Insulin resistance and beta-cell function were calculated using HOMA. Leptin levels were found to be associated with all measures of beta-cell secretion: with fasting and 2 hours insulin and C-peptide, with intact and des-31,32-proinsulin concentrations, and with beta-cell secretion estimated with HOMA. This association was independent of age and body fat in women, but in men, associations with insulin and C-peptide weakened after controlling for fat mass, whereas those with intact and des-31,32-proinsulin disappeared. Fasting insulin and C-peptide levels were also significant in multiple regression analyses, besides gender and fat mass. Insulin resistance, as assessed by HOMA, was strongly correlated with leptin, also after correction for age and fat mass in both genders. We conclude that, besides fat mass and gender - the main determinants for leptin levels in type 2 diabetic subjects as in healthy subjects - insulin secretion and the degree of insulin resistance also seem to contribute significantly to leptin levels.

Adipose Tissue↗
PubMed2003

Laparoscopic-assisted gastric button placement: a valuable alternative for a percutaneous endoscopic gastrostomy (PEG).

A percutaneous endoscopic gastrostomy remains the first choice when oral feeding is difficult. In some patients however an endoscopic placement of a gastrostomy tube is not possible. As an alternative, a laparoscopic-assisted insertion of a gastric button was performed to provide enteral feeding in seven patients. Enteral feeding could be resumed within one or two days after the procedure and no complications were encountered. This minimal invasive technique has certain advantages over a surgical gastrostomy by laparotomy. Therefore, a laparoscopically inserted gastric button should be considered a valuable alternative if percutaneous endoscopic gastrostomy is no longer possible.

Aged↗
PubMed2002

Effects of intravenous supplementation with alpha-tocopherol in patients receiving total parenteral nutrition containing medium- and long-chain triglycerides.

OBJECTIVE: To compare the effects of a lipid emulsion containing medium-chain triglycerides (MCT) and supplemented with alpha-tocopherol to a conventional long-chain triglyceride (LCT) emulsion. DESIGN: Randomised double blind study. SETTING: Department of Internal Medicine, Antwerp University Hospital. SUBJECTS AND INTERVENTIONS: Twenty-four patients with an indication for total parenteral nutrition for a minimum of 10 days were randomly assigned to two groups: group E received as lipid source MCT/LCT (50/50) suplemented with 100 mg DL-alpha-tocopherol/day and group C received LCT. Blood samples were analysed at inclusion, after 4-6 and after 9-11 days. RESULTS: In group E, serum alpha-tocopherol doubled from 11.4+/-6.9 at inclusion to 20.9+/-7.9 and to 23.8+/-8.8 microg/ml after 4 and 9 days, respectively, but did not change in group C (P=0.008). Production of thiobarbituric acid-reacting substances (TBARS) after 120 min incubation with copper decreased from 66+/-34 at inclusion to 29+/-25 nmol MDA/mg LDL and VLDL-cholesterol after 4 and to 42+/-17 after 9 days (P=0.022 when compared to group C, which underwent no significant changes). Velocity of production of fluorescent products decreased in group E but not in group C (P=0.026). CONCLUSIONS: Supplementation of TPN containing MCT/LCT with 100 mg DL-alpha-tocopherol/day leads to a doubling in serum alpha-tocopherol and to a decrease in the susceptibility of LDL and VLDL to peroxidation in vitro. SPONSORSHIP: This study was partly financed by B Braun Medical NVSA, Diegem, Belgium.

Adolescent↗
PubMed2001

Antioxidant status and lipoprotein peroxidation in chronic fatigue syndrome.

The aetiology and pathogenesis of the Chronic Fatigue Syndrome (CFS) are still largely unresolved. Accompanying metabolic disorders such as selective n-6 fatty acid depletion suggest that oxidative stress and more specifically lipid peroxidation might play a role in its pathogenesis. In order to investigate this hypothesis, oxidant-antioxidant status and its impact on lipoprotein peroxidation in vitro was examined in 61 patients with unexplained fatigue lasting more than 1 month. They were subdivided into 2 groups: group CFS+ (33 subjects) fulfilled the 1988 Center of Disease Control criteria for CFS and group CFS- did not but was similar as regards age, sex distribution and clinical characteristics. Antioxidant status was similar in the 2 groups except for lower serum transferrin in the CFS + (mean (95 % CI) 2.41 (2.28-2.54) versus 2.73 (2.54-2.92) g/L in the CFS-, p = 0.009) and higher lipoprotein peroxidation in vitro: 6630 (5949-7312) versus 5581 (4852-6310) nmol MDA/mg LDL and VLDL cholesterol x minutes, p = 0.035). CFS intensified the influence of LDL cholesterol (p = 0.012) and of transferrin (p = 0.045) on peroxidation in vitro, suggesting additional pro-oxidant effects. These results indicate that patients with CFS have increased susceptibility of LDL and VLDL to copper-induced peroxidation and that this is related both to their lower levels of serum transferrin and to other unidentified pro-oxidising effects of CFS.

Adult↗
PubMed2001

Divergent effects of different oxidants on glutathione homeostasis and protein damage in erythrocytes from diabetic patients: effects of high glucose.

Long-term complications of diabetes mellitus have been ascribed to both the effects of prolonged hyperglycemia and to increased oxidative stress. In an attempt to identify the mechanisms underlying the acute effects of hyperglycemia on oxidative stress, we investigated the hypothesis that high glucose might lead to an insufficiency in reducing equivalents (such as NADPH) and thus to a disruption in the glutathione-dependent antioxidant defences and to an incapacity to deal with oxidant attack. For this purpose, erythrocytes from diabetic patients were incubated for 0-90 min in 5.55 or 33.3 mM D-glucose containing tertbutyl hydroperoxide 0.5 and 1 mM, Menadione 100 microM, or glucose oxidase. The time course of the changes in non-protein bound glutathione (reduced and oxidised), lactate and pyruvate, alanine and fluorescent products of oxidative proteolysis, hemolysis and methemoglobin was monitored. The results show that although glucose utilisation was unaffected, all oxidants caused a persistent decrease in total non-protein-bound glutathione suggesting binding to proteins. However, changes in glutathione and redox status differed between the various oxidants and were not directly related to the extent of oxidative cellular damage. In these experimental conditions, with short incubations and using the erythrocyte as the simplest cellular model of glucose metabolism, neither high glucose nor the diabetic condition worsened the susceptibility of erythrocytes to acute in vitro oxidative damage.

Blood Glucose↗
PubMed2001

Visceral fat is a determinant of PAI-1 activity in diabetic and non-diabetic overweight and obese women.

Plasminogen activator inhibitor type 1 (PAI-1), an inhibitor of fibrinolysis and an important and independent cardiovascular risk factor, has been shown to be elevated in obesity and type 2 diabetes. Recent study results have suggested that adipose tissue--visceral fat in particular--could play an important role in the fibrinolytic process.In order to assess the specific role of this fat distribution, we measured PAI-1 activity (AU/ml) and visceral fat (CT-scan at level L4-L5) in 2 groups of 30 overweight and obese diabetic and overweight and obese non-diabetic women. Subjects were matched for age, weight, body mass index, fat mass and total abdominal fat. Visceral adipose tissue and PAI-1 were significantly higher in diabetic women (p = 0.022 and p = 0.004 respectively) than in non-diabetic patients. Visceral fat correlated significantly with PAI-1 activity, even after correction for insulin and triglycerides (r = 0.28, p = 0.034). Stepwise regression analysis showed visceral fat as the most important determinant factor for PAI-1 in the whole group and in the non-diabetic group. In the diabetic group, fasting insulin was the most important determinant. These results show that visceral fat is more important than BMI or total body fat in the determination of PAI-1 levels. Furthermore, the increased amount of visceral fat in type 2 diabetics may contribute to the increase of PAI-1 activity levels and the subsequent increased risk for thrombovascular disease, regardless of BMI and total fatness.

Abdomen↗
PubMed2001

Long-term pharmacologic doses of vitamin E only moderately affect the erythrocytes of patients with type 1 diabetes mellitus.

In erythrocytes from diabetic patients, increased membrane lipid peroxidation might lead to abnormalities in composition and function. To study this relationship, we investigated the effects of a moderate pharmacologic dose of vitamin E for 1 y on erythrocyte membrane peroxidation in vitro and on its fatty acid composition, antioxidant capacity and rheological function. In a random and double-blind manner, type 1 diabetic patients (n = 44) were assigned to the following two groups: Group S received 250 IU (168 mg) d-alpha tocopherol 3 times daily for 1 y. Group P received placebo for 6 mo followed by d-alpha-tocopherol for an additional 6 mo. Variables were monitored every 3 mo. After 3 mo of supplementation, serum vitamin E doubled (P < 0.0005), thiobarbituric acid reactive substances in erythrocyte membranes incubated with tert-butyl hydroperoxide decreased by 25% (P = 0.006) and the lagtime of fluorescence increased from 28 +/- 16 to 41 +/- 28 min (P = 0.028). Patients who did not respond to supplementation (13 of 44) had lower serum lipids (P = 0.017) and body mass index (P = 0.024). We did not detect any significant effects of vitamin E supplementation on membrane lipid composition, antioxidant capacity or blood viscosity. Continuing supplementation for up to 1 y did not further affect serum vitamin E or membrane peroxidation. Stopping supplementation was followed by a return to inclusion values. These results show that the decrease in erythrocyte membrane peroxidation after vitamin E supplementation is moderate, saturable, reversible, restricted to some individuals and has no detectable effect on erythrocyte composition and function.

Adult↗
PubMed2000

Cost and resource utilization for prevention and treatment of foot lesions in a diabetic foot clinic in Belgium.

This prospective observational study was carried out to assess the annual preventive and curative treatment costs for diabetic foot problems. Measures of resource use over the 1-year study period were taken for 151 patients whose lesions covered the entire Wagner classification. Treatment was provided under the current protocols of a multidisciplinary team. The 1993 market prices for health services were used to convert units of health service utilization to expenditures by the social insurance system and the patients. The severity of the foot problems determined the medical cost. Preventive care (47 cases), represented an average cost per case of US$ 880 (1US$ 1993=BEF 30.65). Curative care (120 cases), including diagnostic tests, wound dressings, antibiotic therapy, revascularization and off loading techniques resulted in a mean cost of US$ 5227 per ulcer. Care for the 16 most severe wounds and amputations involved hospitalization and surgery at a mean cost per ulcer of US$ 31716. The most important cost contributers were hospitalizations (72%), drugs (11%) and diagnostic examinations (4%). Preventive treatment for diabetic foot problems can represent a significant saving for the social insurance system as well as for the patients.

Anti-Bacterial Agents↗
PubMed2000

Associations of leptin with body fat distribution and metabolic parameters in non-insulin-dependent diabetic patients: no effect of apolipoprotein E polymorphism.

Leptin levels have been shown previously to be associated with anthropometric parameters such as the body mass index (BMI), total body fat, and subcutaneous fat. Since apolipoprotein E (apoE) polymorphism is known to be a genetic marker affecting the relationship between certain anthropometric and metabolic parameters, we evaluated whether the leptin level and/or associations between the leptin level and body composition in non-insulin-dependent diabetic patients could be determined by apoE polymorphism. In 171 type 2 diabetic patients (105 male and 66 female), body composition (BMI, waist to hip ratio [WHR], fat mass, and visceral fat) was measured and fasting blood samples were obtained to determine the apoE genotype, leptin, glucose, and insulin levels, and the lipid profile. The mean leptin level for the whole group was 11.7 +/- 9.3 ng/mL, with a significant difference (P < .001) between men (7.1 +/- 4.9 ng/mL) and women (19.0 +/- 10.1 ng/mL). No difference was found for leptin levels or anthropometric variables between the 3 different apoE genotypes (E3/E3 homozygotes, E2 carriers, and E4 carriers). Only low-density lipoprotein (LDL) cholesterol was significantly different between the 3 apoE subgroups. The correlations of leptin with anthropometric variables, especially visceral fat, tended to be different between the 3 apoE groups, but this was not independent and no effect was found after controlling for the other parameters in the model. A multiple regression model containing gender, subcutaneous fat, fasting glucose, triglycerides, and high-density lipoprotein (HDL) cholesterol explained 81% of the variance in leptin levels. We conclude that apoE polymorphism has no effect on the leptin level or its associations with other anthropometric and metabolic parameters.

Apolipoproteins E↗
PubMed2000

Magnesium status and parameters of the oxidant-antioxidant balance in patients with chronic fatigue: effects of supplementation with magnesium.

OBJECTIVE: Magnesium deficiency and oxidative stress have both been identified as pathogenic factors in aging and in several age-related diseases. The link between these two factors is unclear in humans although, in experimental animals, severe Mg deficiency has been shown to lead to increased oxidative stress. METHODS: The relationship between Mg body stores, dietary intakes and supplements on the one hand and parameters of the oxidant-antioxidant balance on the other was investigated in human subjects. RESULTS: The study population consisted of 93 patients with unexplained chronic fatigue (median age 38 years, 25% male, 16% smokers and 54% with Chronic Fatigue Syndrome (CFS). Mg deficient patients (47%) had lower total antioxidant capacity in plasma (p=0.007) which was related to serum albumin. Mg deficient patients whose Mg body stores did not improve after oral supplementation with Mg (10 mg/kg/day) had persistently lower blood glutathione levels (p=0.003). In vitro production of thiobarbituric acid reactive substances (TBARS) by non-HDL lipoproteins incubated with copper was related to serum cholesterol (p<0.001) but not to Mg or antioxidants and did not improve after Mg supplementation. In contrast, velocity of formation of fluorescent products of peroxidation (slope) correlated with serum vitamin E (p<0.001), which was, in turn, related to Mg dietary intakes. Both slope and serum vitamin E improved after Mg supplementation (p<0.001). CONCLUSIONS: These results show that the lower antioxidant capacity found in moderate Mg deficiency was not due to a deficit in Mg dietary intakes and was not accompanied by increased lipid susceptibility to in vitro peroxidation. Nevertheless, Mg supplementation was followed by an improvement in Mg body stores, in serum vitamin E and its interrelated stage of lipid peroxidation.

Adolescent↗
PubMed2000

Effects of long-term supplementation with moderate pharmacologic doses of vitamin E are saturable and reversible in patients with type 1 diabetes.

BACKGROUND: Vitamin E supplementation has been proposed as adjunctive therapy to counteract the increased LDL oxidation in diabetes and thus prevent or delay cardiovascular complications. OBJECTIVE: The objective of this study was to investigate the effect of a moderate pharmacologic dose of vitamin E for </=1 y in patients with type 1 diabetes. DESIGN: The study was double blind and the subjects were randomly assigned to 2 groups: the supplemented group (group S; n = 22) received 250 IU (168 mg) RRR-alpha-tocopherol 3 times/d for 1 y and the placebo group (group P; n = 22) received a placebo for 6 mo followed by 250 IU (168 mg) RRR-alpha-tocopherol 3 times/d for an additional 6 mo. RESULTS: Serum vitamin E doubled after 3 mo of supplementation, from a mean (+/-SD) of 36.9 +/- 10.9 to 66.4 +/- 18.3 micromol/L (P: < 0.0005). Although lipid profiles, glycated hemoglobin, and blood biochemistry values did not change significantly, copper-induced in vitro peroxidizability of LDL and VLDL decreased after 3 mo of supplementation: the production of thiobarbituric acid-reactive substances decreased by 30-60% (P: < 0. 005) and the lag time for the appearance of fluorescent products increased from 107 +/- 25 to 123 +/- 30 min in group S (P: = 0.002 compared with group P). Vitamin E supplementation for an additional 3-9 mo resulted in no further changes in serum vitamin E and lipoprotein peroxidizability. Values returned to baseline after supplementation ended. CONCLUSIONS: Because the improvement in lipoprotein peroxidizability is saturable and reversible, life-long supplementation with vitamin E should be considered in patients with type 1 diabetes.

Adult↗
PubMed2000

Platelet prothrombinase activity, a final pathway platelet procoagulant activity, is overexpressed in type 1 diabetes: no relationship with mean platelet volume or background retinopathy.

There is overwhelming evidence that platelets from diabetic individuals are hyperreactive, not only when microvascular complications are apparent, but already at an early stage of the disease. There is still controversy about the question of whether primary hyperreactive platelets may contribute to the origin or progression of microangiopathy or whether diabetic platelet hyperfunctionality is just a logical consequence of a continuous low-grade activation of platelets by contact with a diseased microvascular wall. As a consequence of platelet activation, the outer layer of its phospholipid membrane is more procoagulant than in the quiescent state, stimulating thrombin formation in plasma. This platelet function is called platelet procoagulant activity. We studied platelet prothrombinase activity (PPA), a final pathway platelet procoagulant activity of type 1 diabetic platelets, and looked for an eventual correlation with microvascular disease (background retinopathy) and mean platelet volume (MPV). Stypven clotting times (SCTs), reflecting PPA expression, and MPV of citrated platelet-rich plasma (PRP), were measured in 21 patients with type 1 diabetes-10 with and 11 without background retinopathy-under clinically acceptable metabolic control and compared them to 20 disease-free voluntary controls. We also compared PPA expression and MPV in diabetic individuals with and without retinopathy. With the SCT, a selective test adapted for studying PPA in PRP, we found hyperexpression of PPA in all diabetic patients. We found no difference in MPV between diabetic and control PRP. Comparing patients with and without background retinopathy we found no significant difference in PPA expression. From these results, we suggest that the phospholipid surface of diabetic platelets, more than the surface of normal control platelets, stimulate the expression of PPA. This diabetic platelet coagulant anomaly was not related to an increased platelet mass (higher MPV) nor to the presence of microangiopathy. We conclude that PPA hyperexpression is associated with patients with type 1 diabetes, already occurring in an early stage of the disease, and not necessarily a consequence of early-stage microvascular disease, because the anomaly is also demonstrable, in the same degree, in patients with diabetes without microangiopathy.

Adult↗
PubMed2000

Are low magnesium levels in type 1 diabetes associated with electromyographical signs of polyneuropathy?

OBJECTIVE: Our aim was to study the relationship between the magnesium status in type 1 diabetic patients and disturbances in nerve conduction velocity. Furthermore we wanted to investigate whether repletion of magnesium depletion could improve the decreased nerve conduction velocity measurements. In a cross-sectional study, 154 type 1 diabetic patients were screened for their erythrocyte magnesium content and an electrophysiological measurement of the peripheral nervous system was carried out. In a subsequent intervention study, out of this screened population, 23 type 1 patients, with disturbed nerve conduction velocity measurements and low erythrocyte magnesium levels [< 2.3 mmol/L) were given oral magnesium supplements, during 1 year. Twenty type 1 patients with identical characteristics served as controls. In the cross-sectional study disturbed nerve conduction velocities were found in the older patients, in patients with a longer duration of diabetes and a worse metabolic control. EMG polyneuropathy signs were significantly more frequent in diabetic patients with low erythrocyte Mg. The intervention study demonstrated that under unchanged metabolic control, supplementation with magnesium could improve nerve conduction, especially in younger patients with a shorter duration of diabetes. Erythrocyte Mg was lower in type 1 diabetic patients with polyneuropathy. Mg supplementation increasing Mg RBC might (possibly?) improve nerve conduction measured by electromyography at least in younger patients with a short duration of diabetes and presenting early signs of the neurological complication.

Adult↗