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Introduction: La prévalence du MODY est sous-estimée en raison de la difficulté à distinguer un diabète de type monogénique d’un DT2 précoce. Patients et méthodes: Évaluation phénotypique de 155 patients suspects de MODY ayant bénéficié d’un séquençage des gènes GCK et HNF1A. Comparaison de la probabilité d’être atteints d’un MODY selon les critères classiques du MODY et selon les algorithmes proposés par Shields et par Béllanné-Chantelot. Résultats: 15 patients présentent un MODY 2, 20 un MODY 3 et 119 aucune mutation de GCK ni d’HNF1A (Groupe ű Non mutés Ƈ). Le phénotype des patients MODY 2 et MODY 3 nous ont amené à définir des ű critères élargis Ƈ qui sont : âge au diagnostic < 40 ans, IMC < 30kg/m2, ≥ 3 générations atteintes, dont au moins 2 avant l’âge de 40 ans. Les ű Non mutés Ƈ sont significativement plus âgés et ont un IMC plus élevé. Les patients MODY 2 et MODY 3 ont plus souvent ≥ 3 générations atteintes et un âge au diagnostic chez les apparentés plus bas. Les algorithmes retrouvent des probabilités de MODY plus élevées chez les patients mutés que chez les ű Non mutés Ƈ. Cependant, parmi les ű Non mutés Ƈ, 21 patients présentent les ű critères élargis Ƈ du MODY et 17 autres ont une probabilité de MODY X selon Shields > 25 %. 6 autres patients présentent des anomalies morphologiques rénales orientant vers une anomalie génétique du développement. Conclusion: Le profil phénotypique des ű Non mutés Ƈ est variable vraisemblablement constitué de patients porteurs d’un MODY et de patients DT2. L’utilisation de critères diagnostiques ű élargis Ƈ et d’outils prédictifs proposés en ligne permet d’extraire, de ce groupe, 44 patients éligibles pour la poursuite des explorations génétiques, rendues possibles par le développement de nouvelles méthodes de criblage génétique étendu. [ABSTRACT FROM AUTHOR]

Normal metabolic balance is maintained by a complex homeostatic system involving multiple tissues and organs. Acquired or inherited defects associated to environmental factors in any part of this system can lead to metabolic disorders such as the syndrome X which is presently a frequent syndrome in industrialized countries. It is characterized by a cluster of risk factors of atherosclerosis including insulin resistance, hyperinsulinemia, impaired glucose tolerance or type 2 diabetes, hypertension, dyslipidemia, and coagulation abnormalities. Its pathophysiology is likely to involve insulin resistance at the level of both skeletal muscle and visceral adipose tissue and altered fluxes of metabolic substrates between these tissues that in turn impair liver metabolism. Therapeutic intervention favours at present diet and exercise prescriptions. In addition, if necessary, specific treatment of the metabolic disorders is required. In the treatment of insulin resistance, new promising drugs are likely to be used in the next future. In this regard, adipose tissue, once thought to function primarily as a passive depot for the storage of excess lipid, is now understood to play a much more active role in metabolic regulation, secreting a variety of metabolic hormones and actively functioning to prevent deleterious lipid accumulation in other tissues and to modulate the insulin resistance. Here, we review new advances in our understanding of mechanisms leading to insulin resistance and type 2 diabetes from the perspective of the role and interactions of recently identified adipocyte-specific chemical messengers, the adipocytokines, such as adiponectin, tumor necrosis factor-alpha, interleukin 6, and resistin.

Normal metabolic balance is maintained by a complex homeostatic system involving multiple tissues and organs. Acquired or inherited defects associated to environmental factors in any part of this system can lead to metabolic disorders such as the syndrome X which is presently a frequent syndrome in industrialized countries. It is characterized by a cluster of risk factors of atherosclerosis including insulin resistance, hyperinsulinemia, impaired glucose tolerance or type 2 diabetes, hypertension, dyslipidemia, and coagulation abnormalities. Its pathophysiology is likely to involve insulin resistance at the level of both skeletal muscle and visceral adipose tissue and altered fluxes of metabolic substrates between these tissues that in turn impair liver metabolism. Therapeutic intervention favours at present diet and exercise prescriptions. In addition, if necessary, specific treatment of the metabolic disorders is required. In the treatment of insulin resistance, new promising drugs are likely to be used in the next future. In this regard, adipose tissue, once thought to function primarily as a passive depot for the storage of excess lipid, is now understood to play a much more active role in metabolic regulation, secreting a variety of metabolic hormones and actively functioning to prevent deleterious lipid accumulation in other tissues and to modulate the insulin resistance. Here, we review new advances in our understanding of mechanisms leading to insulin resistance and type 2 diabetes from the perspective of the role and interactions of recently identified adipocyte-specific chemical messengers, the adipocytokines, such as adiponectin, tumor necrosis factor-alpha, interleukin 6, and resistin.

A familial lympho-epithelial thymoma with constitutional chromosomal translocation t (14;20) (q24;p13) is presented: the thymoma and its particular translocation are present in the mother and the two sons of her offspring. The small number of cases do not allow establishing any relation between thymoma and this particular translocation. Concerning genetic counseling, an annual thoracic radiography is necessary for all the other family members, carriers or not of the translocation.

Unfixed, isolated metaphase chromosomes were used as template in an in vitro RNA synthesis assay. In these conditions, no RNA synthesis was observed by autoradiography. Transcription was effective after treatment with methanol-acetic acid, HCl 0,2 N, NaCl 0,35 M or pancreatic RNase. Transcription is the most important after treatment with RNase. This result points out the problem of the role of RNA in inhibition of chromosome during mitosis.

The case of a 6-year-old male patient suffering from X-chromosome-linked ichthyosis is presented. There was no steroid sulfatase activity in the proband's leucocytes and cutaneous fibroblasts. The activity was decreased in the proband's mother's leucocytes and in one brother, affected by a mild ichthyosis. Basal plasma levels of dehydroepiandrosterone and its sulfate were normal for the patient's age, suggesting that sulfates do not play a significant role in the production of free steroids. After 3 intramuscular injections of 1,500 units of human chorionic gonadotropin, plasma levels of testosterone increased normally, indicating that there was no associated primary gonadal insufficiency.

Isolated metaphase chromosomes from KB cells were used as template in an in vitro DNA synthesis assay. In these conditions, no synthesis was noticed, confirming template inactivity of isolated metaphase chromosomes. DNA synthesis was noticed after a pretreatment with either methanol-acetic acid or RNase A. Analysis of in vitro synthesized polydeoxyribonucleotides showed two fractions of 4 S and 7-8 S. These results suggest the presence in metaphase chromosome of single stranded DNA sequences. Such sequences are shown in DNA extracted from chromosomes. They would preexist in this organelle and would be unmasked by the treatments that restore template activity of metaphase chromosome.

Linked DNA probes have been used in three families presenting an affected child with cystic fibrosis. The strategy used for the determination of haplotypes associated with parental normal and mutated genes is presented as well as its application to the detection of cystic fibrosis carriers among healthy children.

Topographic diagnosis of adrenal pheochromocytoma were determined by ultrasonography in all 6 cases studied and by radiocholesterol scintigraphy in 6 out of 7 cases studied. It would appear that ultrasonography is preferable in the localization of an abdominal pheochromocytoma, whether adrenal or extra-adrenal. Intravenous urography along with rapid sequence nephrotomography and radiocholesterol scintigraphy, play a complementary role in confirming the topographic diagnosis. In case these methods prove unsuccessful or provide conflicting results, it is then possible to consider computed tomography, angiography and caval catheterization.