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Biomedical subjects

S Halimi

Publications and source records attributed to S Halimi.

At least 19 recordsLinked to original sources

2'-deoxyguanosine oxidation is associated with decrease in the DNA-binding activity of the transcription factor Sp1 in liver and kidney from diabetic and insulin-resistant rats.

Over the years, several lines of evidence have emerged supporting the role of oxidative stress in the development of diabetic complications. This could involve the increase in the production of reactive oxygen species and the decrease in antioxidative defense systems. Modulation of the level of intracellular reactive oxygen species is likely to affect the intracellular redox homeostasis, which is crucial for numerous biological events such as the transcriptional activation of genes. In this work we studied the binding of the redox transcription factors Sp1 and NF-kappaB extracted from kidney and liver of streptozotocin diabetic (STZ) and fructose-fed rats using electrophoretic mobility shift (EMSA) assay. In addition, the level in 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo) was assessed within DNA by high performance liquid chromatography with electrochemical detection (HPLC-EC). A decrease in the affinity of Sp1 to DNA was observed in the kidney of STZ rats and fructose-fed rats (15% +/- 8.3 and 54% +/- 6.9, respectively, versus control group set to 100%). This was also found to occur to a lower extent, in the liver. Interestingly, higher levels of 8-oxodGuo, a biomarker of DNA oxidation, were measured in the kidney of diabetic rats. Therefore, the modification in the binding efficiency of Sp1 or NF-kappaB could be related to reactive oxygen species-mediated DNA damage.

8-Hydroxy-2'-Deoxyguanosine↗

Variations of ambulatory blood pressure with position in patients with type 1 diabetes: influence of disease duration and microangiopathy in a pilot study.

OBJECTIVE: To study the influence of position changes on 24-h ambulatory blood pressure (ABP) in normotensive or mildly hypertensive normoalbuminuric patients with type 1 diabetes. RESEARCH DESIGN AND METHODS: A cross-sectional evaluation of patients was staged according to the duration of diabetes (DD) and the presence of microangiopathy. We recruited 37 patients (30 men and 7 women), aged 38 +/- 12 years, who were normotensive or mildly hypertensive (diastolic blood pressure [DBP] <105 mmHg) and free of antihypertensive treatment and microalbuminuria. They were included according to DD (group 1, <5 years; group 2, > or =10 years). An additional group of seven diabetic patients with microalbuminuria and mild untreated hypertension was also investigated. We recorded 24-h ambulatory blood pressure every 15 min with a position sensor, which allowed for the discrimination between standing or supine/sitting position in the patient. RESULTS: Mean daytime (10:00 A.M. to 8:00 P.M.) ABP in supine/sitting position did not significantly differ between groups 1 and 2. However, standing ambulatory systolic blood pressure (ASBP) and ambulatory DBP (ADBP) were significantly higher than supine/sitting ASBP and ADBP in group 1 (DeltaSBP 4 +/- 5, DeltaDPB 4 +/- 6 mmHg, P < 0.01) but not in group 2 (DeltaSBP 2 +/- 8, DeltaDBP 2 +/- 4 mmHg, P = NS). Patients free of microangiopathy presented with significantly higher ABP in standing position than in sitting/lying position, whereas patients with retinopathy and/or nephropathy exhibited no significant increase of ABP during standing. CONCLUSION: The monitoring of position during ambulatory measurement of blood pressure in type 1 diabetic patients shows different patterns in relation to disease duration and the presence of microangiopathy.

Adult↗

Multicenter randomized evaluation of a nutritional education software in obese patients.

OBJECTIVE: To study the efficacy of the nutritional education software, Nutri-Expert, in the management of obese adult patients. MATERIAL AND METHODS: Two groups of obese patients were followed up over one year in a randomized study: the first group received close traditional management (seven nutritional visits over the year, with physicians and dietitians conjointly) and the second one also used at home by Minitel the Nutri-Expert system. 557 patients were enrolled in the study by 16 French centers of diabetology and nutrition. Body mass index (BMI), tests of dietetic knowledge, dietary records and centralized biological measurements were assessed at inclusion, 6 and 12 months. 341 patients were evaluable at the end of the year. RESULTS: The group using Nutri-Expert scored significantly better in the tests of dietetic knowledge than the control group. For all patients, nutritional education led to a significant improvement in BMI, dietary records and biological measurements, without significant difference between the two groups. Five years after the end of the study, the weight of 148 patients was recorded; mean BMI was significantly lower than the initial value but there was no significant difference between the two groups. CONCLUSION: In the management of obese patients, Nutri-Expert system has a role to play in reinforcing nutritional knowledge; if regular follow-up is not possible, or if a large series of obese patients is to be treated, Nutri-Expert could partly replace traditional management, for example between visits.

Adult↗

[Type 2 diabetes mellitus: Which place for thiazolidinediones in the therapeutic strategy?].

Several new pharmacological agents have recently been developed to optimise the management of type 2 diabetes mellitus. The aim of this article is to briefly review the new therapeutic class: thiazolidinediones (TZD), acting as these insulin sensitizer and to suggest a logical use of these drugs in the guidelines proposed by the french recommendations for the treatment of type 2 diabetic subjects. These agents are now introduced in Europe, only in combination with metformin or sulfonylureas (or glinides). Moreover, some preliminary data indicate that these agents could delay the decrease of insulin secretion by the beta pancreatic cells and could reduce other cardiovascular risk factors often associated with type 2 diabetes: hypertension and lipid abnormalities, by reducing blood pressure, triglycerides and increasing HDL cholesterol. These new drugs bring some hope in the treatment of type 2 diabetic patients in combination with the previous oral anti-diabetic drugs which have recently demonstrated (UKPDS) their ability to prevent or to reduce complications due to diabetes. However the frequency of adverse events must be evaluated in a large use, beyond phase II and III, after the withdrawal of the first TZD introduced on the market (troglitazone).

Diabetes Mellitus, Type 2↗

[Heterogeneity of nephropathies in type 2 diabetes].

DIVERSE KIDNEY DISORDERS: Patients with type 2 diabetes mellitus who develop nephropathy can have various types of disorders capable of progressively destroying the kidneys. It is now clear that the same type of diffuse or nodular glomerulosclerosis develops irrespective of the type of diabetes, i.e. the pathophysiology of hyperglycemia. HETEROGENEITY: There is however a certain degree of heterogeneity in terms of clinical presentation, clinical course and response to treatment. Heterogeneity is due to age, the number of different accumulated risk factors and disease states, genetic factors that are in the process of being identified, and finally, lesions to the urologic apparatus, the arteries, and the renal parenchyma itself that are not directly caused by diabetes. PRACTICAL IMPACT: Mixed lesions, due to both diabetic and non-diabetic causes, may therefore exist in the same kidney. These different possibilities should be systematically considered in order to adopt an individualized investigative and therapeutic attitude for each new patient.

Biopsy↗

Efficacy and safety of acarbose add-on therapy in the treatment of overweight patients with Type 2 diabetes inadequately controlled with metformin: a double-blind, placebo-controlled study.

This 6-month, double-blind, placebo-controlled, randomised, parallel-group study investigated the potential of acarbose add-on therapy for improving the glycaemic control of overweight patients with Type 2 diabetes and was inadequately controlled with metformin monotherapy. Patients were randomised to receive acarbose titrated up to 100 mg three times daily (n=74) or placebo (n=78). All patients were receiving metformin 850 mg twice or thrice daily before the study and continued to receive this dose throughout the study. The mean difference in glycated haemoglobin (HbA(1c)) (+/-S.D.) from baseline to endpoint was -0.7+/-1.2% U in the acarbose intention-to-treat (ITT) group, compared with +0.2+/-1.3% in the placebo ITT group (P=0.0001). Significantly, more patients in the acarbose group were classified as 'responders', with an HbA(1c) at the end of treatment of less than 7.0% or a decrease by at least 15% relative to baseline (acarbose vs. placebo; 42 vs. 17%; P=0.002). The difference in fasting blood glucose level from baseline to endpoint was -1.0+/-2.8 (S.D.) mmol/l in the acarbose ITT group, compared with +1.3+/-2.8 mmol/l in the placebo ITT group (P=0.0001), and for 2-h postprandial blood glucose level -1.4+/-3.8 vs. +1.1+/-3.5 mmol/l (P=0.0001). In all, 60% of patients in the acarbose group and 33% in the placebo group had an adverse event considered to be possibly or probably related to drug therapy, leading to withdrawal by 15 and 3%, respectively. The results indicate that acarbose has potential clinical utility for improving glycaemic control in overweight patients with Type 2 diabetes inadequately controlled with metformin.

Acarbose↗

Ratio of triglycerides to HDL cholesterol is an indicator of LDL particle size in patients with type 2 diabetes and normal HDL cholesterol levels.

OBJECTIVE: In patients with type 2 diabetes, a normal HDL cholesterol level does not rule out that LDL particles may be small. Although techniques for analyzing LDL subfractions are not likely to be used in clinical practice, a prediction of LDL size based on a regular lipid profile may be useful for assessment of cardiovascular risk. RESEARCH DESIGN AND METHODS: Sixty patients with type 2 diabetes with acceptable glycemic control and an HDL cholesterol level > or = 1 mmol/l were recruited after cessation of lipid-altering treatments. LDL size was determined by 2-20% PAGE; patients having small LDL (n = 30) were compared with those having intermediate or large LDL (n = 30). RESULTS: Clinical characteristics, pharmacological therapies, lifestyle, and prevalence of diabetes-related complications were similar in both patient groups. LDL size correlated negatively with plasma triglycerides (TGs) (R2 = 0.52) and positively with HDL cholesterol (R2 = 0.14). However, an inverse correlation between the TG-to-HDL cholesterol molar ratio and LDL size was even stronger (R2 = 0.59). The ratio was > 1.33 in 90% of the patients with small LDL particles (95% CI 79.3-100) and 16.5% of those with larger LDL particles. A cutoff point of 1.33 for the TG-to-HDL cholesterol ratio distinguishes between patients having small LDL values better than TG cutoff of 1.70 and 1.45 mmol/l. CONCLUSIONS: The TG-to-HDL cholesterol ratio may be related to the processes involved in LDL size pathophysiology and relevant with regard to the risk of clinical vascular disease. It may be suitable for the selection of patients needing an earlier and aggressive treatment of lipid abnormalities.

Aged↗

[Health costs associated with the diabetic foot in developed countries.A plea for the creation of health care networks].

COST OF DIABETIC FOOT: A limited number of epidemiological and economical studies on diabetic foot in France is available. Studies conducted in other countries, namely USA, Netherlands, UK and especially Sweden, have evidenced major direct and indirect costs that generally are underestimated in overall economical cost of diabetes forecast. The rapid increase of diabetes prevalence throughout the world, combined with diabetic population aging, allows to speculate that this situation may dramatically worsen in the future. In order to reduce the economical and human burden of this complication, it is an urgent public health necessity in France to set multidisciplinary organisations, dealing with both in-patient care, which importance should be decreasing, and out-patient care, as well as prevention and foot care networks. The swedish experience figures an interesting model for our healthcare system.

Costs and Cost Analysis↗

Role of metalloproteases and inhibitors in the occurrence and progression of diabetic renal lesions.

Renal remodelling in hyperinsulinic/insulinopenic states is mediated by glucotoxicity, endothelial dysfunction and vascular and nephron collagen turnover. Hypertensive and renal links are renewed by renoprotective interventions of renin-angiotensin. Vasoactive peptide processing and vascular collagen deposition are under the tight control of two zinc metalloproteinase families that regulate vascular tone and trophicity: gluzincins (or vasopeptidases) are convertases of angiotensins, endothelins or atrial natriuretic factors; and metzincins or matrix metalloproteases (MMP, matrixins)] regulate vascular type IV collagen basement membrane proteolysis. Association of natural tissue inhibitors of MMPs, pharmacological inhibitors of vasopeptidases [either conventional (angiotensin-converting enzyme inhibitors) or innovative (omapatrilat)], together with synthetic MMP inhibitors, are currently screened to counteract vascular remodelling and renal scarring. Our studies focused on the 72 kDa (MMP-2) and 92 kDa (MMP-9) matrixin gelatinases and tissue inhibitors involved in basement membrane degradation and rebuilding. Three complementary settings were developed, allowing evaluations from basic to clinical stages. A leucocyte-endothelial transmigration model was designed for transcription and addressing of enzymes and inhibitors, in situ matrix degradation, and blockading by metalloprotease inhibitors (captopril). Insulin-resistant fructose-fed rats showed heavy proteinuria and glomerulosclerosis involving angiotensin II-dependent changes in renal gelatinases and inhibitors. Urinary gelatinolytic profiles from Type 2 diabetic patients with overt nephropathy were compared with those of normal first-degree relatives and age-matched healthy controls. Physiologically, MMP-9 was the primary urinary gelatinolytic enzyme. In Type 2 diabetic proteinuric patients, MMP-9 and MMP-2 releases were significantly increased in the absence of renin-angiotensin blockade, while first-degree relatives showed reduced gelatinase levels suggestive of a genetic control of renal matrix regulation prior to potential glycaemic dysregulation. These preliminary data suggest that local MMP/TIMP imbalance is involved in diabetic renal remodelling. Further studies are needed to define the redundancies and specificities of vasopeptidase and MMP inhibitors, differentiate the antihypertensive effect from target-organ protection, screen for innovative pharmacological compounds, and validate simple, efficient biological markers of renal fibrosis progression and the effect of anti-fibrotic therapeutic interventions.

Animals↗

[Which coronary tests to use in asymptomatic diabetics?].

Coronary artery disease is a common, serious and insidious complication of diabetes. Myocardial ischaemia is often silent. All diabetics do not have the same coronary risk and, therefore, it is important to determine which investigations to perform and which patients. This strategy is justified because it allows identification of these cases which require a medical or an invasive (angioplasty, surgical revascularisation) approach, as these interventions may improve the prognosis. The first stage is clinical (investigation of cardiovascular risk factors). When more than two risk factors are found, further investigations are justified. Exercise stress testing provide reassuring diagnostic and prognostic data when maximal and negative. When sub-maximal, impossible or significantly ischaemic, a second investigation is useful. Holter ECG recording with analysis of ST variation lacks sensitivity and, above all, specificity. The diagnostic value of perfusion myocardial scintigraphy in the diabetic is not as good as that observed in the general population, but its prognostic value remains good. Ischaemia involving over 20% of the myocardium justifies therapeutic investigation. Stress echocardiography has been validated in the diagnosis and prognosis of coronary artery disease and its sensitivity and specificity are probably the same as those of scintigraphy. The authors conclude that the asymptomatic diabetic requires clinical and staged paraclinical investigation to assess prognosis and, depending on the results, the adoption of a beneficial therapeutic strategy.

Cardiovascular Agents↗