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E Renard

Publications and source records attributed to E Renard.

At least 37 records · Page 2Linked to original sources

[Which contraception to choose for the diabetic woman?].

Low-dose oral contraceptives can be used by a great number of women with IDDM or a previous gestational diabetes mellitus. Others hormonal contraceptives (progestogen-only preparations) are less convenient and the compliance is poor with an increasing risk of gynaecologic side effects. The safety of this contraceptives as regards vascular diabetic complications is not evaluated well. Nulliparous patients with progressive complications can use barrier methods of contraception after education. Macroprogestative contraception is a adequate choice for women within forties. For multiparous diabetic women, intra-uterine devices represent the first choice.

Contraceptives, Oral↗

[Insulin therapy in type 1 diabetes for and during pregnancy: by which means and for which objectives?].

Clinical data in the 1980s showed a close relationship between the conceptional glycated hemoglobin and the occurrence of spontaneous early abortions and fetal malformations. Blood glucose level during pregnancy was similarly correlated with the risk of fetal macrosomia, due to significant links between birthweight, fetal hyperinsulinemia and mean maternal blood glucose. Tight blood glucose control from conception to term was shown to be able to lower the risk of fetal malformations and perinatal mortality to that of the offspring of a non diabetic mother. Prerequisites include: 1) contraception until tight blood glucose control, 2) close partnership between diabetologist and obstetrician, 3) assessment of diabetic complications. Seldom, coronary heart disease or advanced nephropathy contraindicate pregnancy. Uncontrolled proliferative or pre-proliferative retinopathy, or macular edema, are temporary contraindications to pregnancy. Laser photocoagulation must then be performed before tightening blood glucose control. A complete review of diabetes management is associated with therapeutic intensification. Blood glucose objectives allow as limits: 70 to 100 mg/dl before meals, up to 140 mg/dl one hour and 120 mg/dl two hours after meals. HbA1c allowing conception is close to 7%. Blood glucose monitoring requires 6-7 measurements per day. The most efficient insulin regimens include 3 to 4 shots per day. The distribution between regular and NPH or lente insulins is adapted individually. Lispro insulin, now appearing as safe, may be used to improve post-meal blood glucose control. Insulin pumps may be useful in case of late-night poor control or frequent hypoglycemic events. Patient acceptance of this option is unavoidable to obtain a benefit. Preconceptional insulin therapy must be maintained until pregnancy term. Follow-up must be intensified after twenty fourth week. Labor and delivery, cesarean section, fetal maturation by corticosteroids and use of i.v. betamimetic drugs require continuous i.v. insulin delivery. The continuation of intensive insulin management in post-partum is encouraged.

Blood Glucose↗

Morphological and molecular differentiation of invasive freshwater species of the genus Corbicula (Bivalvia, corbiculidea) suggest the presence of three taxa in French rivers.

Asiatic Clams are common in brackish and fresh water in Asia, and they were introduced into North America in 1924 and have now spread throughout the continent. During the last two decades they have been reported in Europe, but the number of species here is uncertain. Populations of Corbicula from France and the Netherlands were analysed morphologically and genetically to quantify the degree of species and/or population differentiation. The morphological and genetic data, based on allozymes and mitochondrial sequences, were in full agreement. They indicate that there are two distinct species, identified as C. fluminalis and C. fluminea, in the two countries. Analyses of the mitochondrial COI gene revealed an unexpected divergent population of Corbicula in the Rhône. All these individuals were morphologically identified as C. fluminea, but had a COI sequence different from the two previous species. This population may, therefore, be a more ancient population, or a distinct species introduced via a different colonization route.

Animals↗

[Evaluation of the benefits brought by pregnancy planning in type 1 diabetes mellitus].

Fetal mortality and morbidity remain dramatically increased in diabetic women. To evaluate the benefit of a preconceptional education combined with a good metabolic control, we compared the outcome of pregnancy in 2 groups of type I diabetic women: group A (n = 21) planned before conception versus group B (n = 40) not planned. Both groups were similar related to the type and duration of diabetes, its complications, age, body mass index and different factors of risk. In group A, HbA1C levels were < or = 3 SD of the normal mean of non diabetic values before conception and during the pregnancy course and > or = 3 SD in group B. We observed a significant reduction (p < 0.05) of the main adverse events regarding fetus outcome (fetal, perinatal and neonatal mortality, malformations) and obstetrical complications in the planned group. These data lead to the need of an extensive policy of early planification of pregnancy in diabetic women.

Congenital Abnormalities↗

[How should we use the short-acting insulin analog Lys-Pro in external continuous subcutaneous pumps?].

External pump treatment improves glycemic control, particularly thanks to the continuous basal rate. The pharmacokinetics of the short-acting insulin analog lispro allow a better control of post-prandial hyperglycemia than regular insulin. The use of the short-acting insulin analog in the pump improves HbA1c and blood glucose stability, without increasing the risk of hypoglycemia. Frequent blood glucose self-monitoring is required in order to optimize insulin adjustments, using the retro-active method. Systematic monitoring of urine ketones is also required, for an early detection of any interruption in insulin delivery. Under these conditions, this modality of intensified treatment seems very efficient.

Blood Glucose↗

[Nutritional hypogonadism].

Functional hypothalamic amenorrhea are frequently observed. Body weight, body composition, eating attitudes, exercise are potent modulators of gonadotrop axis. Animal studies and clinical observations stress the fact of a major impact on ovary function of starvation or caloric restriction, weight loss and fat mass deficiency, eating disorders, stress or high intensive exercise training. From a pathophysiological point of view, insulin, IGF's system, leptine and central neuromediators are a link between nutrition and the gonadotropic axis. Initial clinical evaluation may strongly suggest the environmental origin of the amenorrhea. Basal hormonal evaluation (gonadotropins, prolactin, androgens ...) excludes other diseases and specialised evaluations [basal metabolic rate (BMR), Free T3 ...] could confirm the diagnosis. A low BMR, and a low Free T3, a normal FSH level with a low LH level suggest the nutritional origin of the amenorrhea. Improvement of nutritional intake and body composition with a psychological follow up may reverse the gonadotropin deficiency. If this deficiency persists hormonal replacement therapy is added in order to prevent the short or long term consequences (osteoporosis) of hypoestrogenism.

Amenorrhea↗

Syndrome of body fat redistribution in HIV-1-infected patients: relationships to cortisol and catecholamines.

OBJECTIVE: Alterations of body fat distribution have been recently reported in HIV-infected patients. We aimed to investigate whether the hormones modulating adipose tissue metabolism could be implicated. SUBJECTS: We investigated twenty-eight HIV-infected patients who had developed abdominal fat, combined with peripheral lipodystrophy in 25 cases and 'buffalo hump' in 2 cases, but who had otherwise improved on antiretroviral therapies. Twelve patients with no change in body fat, matched for age, disease control and treatment, were studied as controls. MEASUREMENTS: Body composition was assessed by bioelectrical impedance analysis. Subcutaneous (SAT) and visceral (VAT) compartments of total abdominal adipose tissue (TAT) were measured by computed tomography. Resting metabolic rate (RMR) was assessed by indirect calorimetry. Endocrine investigations included plasma thyroid hormones, cortisol, testosterone, oestradiol and 24-hour urinary free cortisol (UFC) and catecholamines. RESULTS: Despite similar body mass index, the patients with body fat alterations showed significantly larger VAT and higher VAT:TAT ratio than controls (P = 0.002 and 0.0001, respectively). In these patients, RMR was significantly higher than estimated according to the Harris-Benedict formula (+ 19.7 +/- 11.6 %, P = 0.0001) and correlated with VAT (r = 0.58, P = 0.003) and 24-hour urinary output of catecholamines (r = 0.67, P = 0.002), that was significantly increased in comparison with controls (1737 +/- 1228 vs 476 +/- 292 nmol, P = 0.013). We also found a significant correlation between VAT and UFC (r = 0.41, P = 0.042) that was absent in controls, although levels of UFC were similar in the two groups. CONCLUSIONS: Our data suggest that body fat redistribution may involve cortisol and catecholamine actions. While high release of catecholamines may enhance RMR through increased lipolysis, cortisol may promote central fat storage. These effects might be related both to persistent hormonal responses to stress becoming inappropriate while disease control improved and to an increased sensitivity of visceral adipose tissue to cortisol in affected patients.

Adipose Tissue↗

[Insulin resistance: from clinical diagnosis to molecular genetics. Implications in diabetes mellitus].

Insulin resistance is observed in several diseases such as non insulin dependent diabetes mellitus (NIDDM) or polycystic ovarian syndrome (PCOS). To understand genetic determinism of this abnormality we have developed a multidisciplinary approach including selection of phenotypes with insulin resistance confirmed in vivo by minimal model of Bergman and characterization of cellular defects in insulin action on circulating erythrocytes and monocytes. Exploration of variability in candidate genes by direct sequencing in some genetic syndromes of severe insulin resistance and acanthosis nigricans (mainly the Type A syndrome) revealed mutations of the insulin receptor gene associated with major defects in insulin binding or kinase activity. In other rare genetic syndromes or patients affected by NIDDM or PCOS defects appear to be located at post-receptor level, where IRS (insulin receptor substrate) genes are the most attractive candidates. Prevalence of some allelic variants suggested a potential role of IRS genes in insulin resistance, although their involvement in the pathogenesis of NIDDM remains controversial. Genotype-phenotype correlations in first degree relatives of an index case caring the Type A syndrome, suggested that association of allelic variants of IRS-1 and IRS-2 with insulin receptor mutations contribute, by synergistic effects, to phenotypic expression of defects in signal transduction. These mechanisms through genetic epistasis, involving several genes in insulin action, fit better with the polygenic nature of current forms of NIDDM and represent a good model in the study of pathogenesis of insulin resistance.

Acanthosis Nigricans↗

Amyrel, a paralogous gene of the amylase gene family in Drosophila melanogaster and the Sophophora subgenus.

We describe a gene from Drosophila melanogaster related to the alpha-amylase gene Amy. This gene, which exists as a single copy, was named Amyrel. It is strikingly divergent from Amy because the amino acid divergence is 40%. The coding sequence is interrupted by a short intron at position 655, which is unusual in amylase genes. Amyrel has also been cloned in Drosophila ananassae, Drosophila pseudoobscura, and Drosophila subobscura and is likely to be present throughout the Sophophora subgenus, but, to our knowledge, it has not been detected outside. Unexpectedly, there is a strong conservation of 5' and 3' flanking regions between Amyrel genes from different species, which is not the case for Amy and which suggests that selection acts on these regions. In contrast to the Amy genes, Amyrel is transcribed in larvae of D. melanogaster but not in adults. However, the protein has not been detected yet. Amyrel evolves about twice as fast as Amy in the several species studied. We suggest that this gene could result from a duplication of Amy followed by accelerated and selected divergence toward a new adaptation.

Amino Acid Sequence↗

Refinement of genetic localization of the Alström syndrome on chromosome 2p12-13 by linkage analysis in a North African family.

Alström syndrome is a rare autosomal recessive disorder characterized by retinal pigment degeneration, neurogenic deafness, infantile obesity, hyperlipidemia, and non-insulin-dependent diabetes mellitus. While the disease-related gene remains unknown, studies of the genetic isolate of French Acadians provisionally locate the Alström syndrome on chromosome 2p12-13 within a 14.9-cM interval. To confirm this finding in another ethnic population and refine the candidate region we investigated by linkage analysis a consanguineous family of North African origin, in which three of seven siblings displayed all major neurological and metabolic features of Alström syndrome. Genotyping was performed on an ABI377 DNA automatic sequencer and LOD scores were obtained with the Fastlink program. Five markers previously investigated in French Acadians confirmed the involvement of the candidate region, although pairwise LOD scores were of poor significance (Zmax = 2.9). To further confirm homogeneity and refine the candidate region, 20 additional markers were investigated. Haplotype analysis and allele segregation revealed that affected children shared a single haplotype and were homozygous for the eight most centromeric markers (D2S291-D2S2114), over a 6.1-cM interval. Significative multipoint LOD scores (Zmax = 3.96) were obtained between markers D2S2110/145 and D2S286. Two clusters of known genes are present in this refined region of chromosome 2p, the most attractive candidate being the hexokinase II gene. However, except for several known polymorphisms, no mutations were detected in the coding region of this gene. In conclusion, the location of Alström syndrome on chromosome 2p12-13 is confirmed, reducing the genetic interval to 6.1 cM.

Abnormalities, Multiple↗

Improvement of HbA1c and blood glucose stability in IDDM patients treated with lispro insulin analog in external pumps.

OBJECTIVE: To compare the efficacy of the short-acting insulin analog lispro (LP) with that of regular insulin in IDDM patients treated with an external pump. RESEARCH DESIGN AND METHODS: Thirty-nine IDDM patients (age, 39.4 +/- 1.5 years; sex ratio, 22M/17W; BMI, 24.4 +/- 0.4 kg/m2; diabetes duration, 22.5 +/- 1.6 years) who were treated by external pump for 5.1 +/- 0.5 years were involved in an open-label, randomized, crossover multicenter study comparing two periods of 3 months of continuous subcutaneous insulin infusion with LP or with Actrapid HM, U-100 (ACT). Boluses were given 0-5 min (LP) or 20-30 min (ACT) before meals. Blood glucose (BG) was monitored before and after the three meals every day. RESULTS: The decrease in HbA1c was more pronounced with LP than with ACT (-0.62 +/- 0.13 vs. -0.09 +/- 0.15%, P = 0.01). BG levels were lower with LP (7.93 +/- 0.15 vs. 8.61 +/- 0.18 mmol/l, P < 0.0001), particularly postprandial BG levels (8.26 +/- 0.19 vs. 9.90 +/- 0.20 mmol/l, P < 0.0001). Standard deviations of all the BG values (3.44 +/- 0.10 vs. 3.80 +/- 0.10 mmol/l, P = 0.0001) and of postprandial BG values (3.58 +/- 0.10 vs. 3.84 +/- 0.10 mmol/l. P < 0.02) were lower with LP. The rate of hypoglycemic events defined by BG < 3.0 mmol/l did not significantly differ between LP and ACT (7.03 +/- 0.94 vs. 7.94 +/- 0.88 per month, respectively), but the rate of occurrences of very low BG, defined as BG < 2.0 mmol/l, were significantly reduced with LP (0.05 +/- 0.05 vs. 0.47 +/- 0.19 per month, P < 0.05). At the end of the study, all but two (95%) of the patients chose LP for the extension phase. CONCLUSIONS: When used in external pumps, LP provides better glycemic control and stability than regular insulin and does not increase the frequency of hypoglycemic episodes.

Adult↗

Identification of two novel insulin receptor mutations, Asp59Gly and Leu62Pro, in type A syndrome of extreme insulin resistance.

To elucidate genetic determinants of insulin resistance, we investigated insulin receptor (IR) and insulin receptor substrate-1 (IRS-1) genes, in vitro IR function and in vivo insulin sensitivity in a family with Type A syndrome. Two missense IR mutations (Asp59Gly and Leu62Pro) found in the proband, resulted in reduction by 90% of insulin binding to erythrocytes, decreased receptor autophosphorylation and a dramatic reduction of insulin sensitivity. The proband and mother were heterozygote for Gly972Arg IRS-1 variant. Asp59Gly mutation, also carried by proband's brother with no consequence on insulin sensitivity, was inherited from the mother who is diabetic and insulin resistant and Leu62Pro was from the father. We conclude that severity of insulin resistance in the proband may be explained by the genetic condition of compound heterozygote for IR mutations while severe insulin resistance in the mother raises the possibility that other genetic factors, like IRS-1 polymorphisms, may contribute to the phenotypic expression of IR mutations.

Amino Acid Sequence↗

Influences of weight, body fat patterning and nutrition on the management of PCOS.

Polycystic ovary syndrome (PCOS) is a heterogeneous clinical entity that is defined as the association of hyperandrogenism with chronic anovulation in women without specific underlying diseases of the adrenal or pituitary glands. PCOS is also associated with a metabolic disturbance (insulin resistance). The nature of the complex interrelation of obesity, insulin resistance and endocrine abnormalities in PCOS remains unresolved. However, several studies link obesity, body fat distribution and nutritional habitus with the hormonal and metabolic profiles of PCOS. Moreover, intervention studies have suggested that reducing weight and/or hyperinsulinaemia either by diet alone or by a combination of diet and drugs improves hirsutism, fertility and the hormonal and metabolic profiles of PCOS. In fact, the evaluation of nutritional factors in PCOS is helpful for the screening of metabolic abnormalities and the management of women with PCOS. A point of particular interest in the management of PCOS is that the choice of contraception remains difficult in these high cardiovascular risk women. The impact of pills with ethinyl oestradiol on weight, body fat distribution and carbohydrate metabolism in women with PCOS has not been thoroughly evaluated. The lack of prospective studies to evaluate long-term metabolic and cardiovascular tolerance necessitates care and the assessment of other hormonal possibilities.

Body Constitution↗

A prospective multicenter trial of octreotide in 24 patients with visual defects caused by nonfunctioning and gonadotropin-secreting pituitary adenomas. French Multicenter Octreotide Study Group.

OBJECTIVE: The somatostatin analog octreotide has been demonstrated to improve optic tract compression caused by pituitary macroadenomas within hours of its administration and/or reduce tumor size in some patients. We report the results of a prospective multicenter study of the effects of octreotide on visual function and tumor size in patients with nonfunctioning pituitary adenomas or gonadotropin-secreting adenomas. METHODS: Twenty-four patients with visual defects caused by histologically confirmed macroadenomas were administered octreotide via continuous subcutaneous infusion, as follows: 100 micrograms the 1st day and, if necessary, 200 micrograms the 2nd and then 100 or 200 micrograms three times daily if visual function improved. Vision was assessed after 4 days, 1 month, and 2 months, including tumor size evaluation. Visual improvement was defined by a net gain of at least 2/10 in acuity and/or of more than 20% of the surface of one isopter (a reduction in tumor volume of > or = 20% of the initial measurement); opposite changes were defined as deterioration. RESULTS: Visual improvement was noted in 13 of 24 patients, 10 of 23 patients and 9 of 22 patients, and was not noted in 11 of 24 patients, 14 of 23 patients, and 13 of 22 patients after 4 days, 1 month, and 2 months, respectively. After 2 months, three adenomas had shrunk, three had not changed in size, and one had increased; visual function improved in the seven patients with these adenomas. Octreotide was discontinued in 13 patients for lack of efficacy. CONCLUSION: The incidence of visual improvement and tumor shrinkage noted in this study was higher than previously reported. Our data suggest that early onset of visual improvement might help in deciding which patients profit from octreotide. However, concomitant gain in visual acuity with deterioration in visual fields or visual improvement with an increase (moderate) in tumor size can occur.

Adenoma↗