Claudio Liberman G

Polimorfismo de la proteína ligante de ácidos grasos intestinal (FABP2), obesidad e insulina resistencia

The genetic components of insulin-resistance, diabetes and obesity have been largely studied. These conditions are determined by multiple polygenic and environmental factors. Certain candidate genes, that have common functional variants in the general population, may be important determinants of inter-individual differences in the response to dietary changes. This review focuses in one of the major candidate genes, the gene encoding for the FABP2, an intracellular protein expressed only in the intestine, involved in the absorption and intracellular transport of dietary long chain fatty acids. Carriers of the Thr54 allele in FABP2 have a 2-fold greater affinity for long chain fatty acids than Ala54 carriers. The increased flux of dietary fatty acids (FA) into the circulation, among carriers of FABP2 Ala54Thr, supports a role of the polymorphism of this allele in the etiology of metabolic disorders. The frequencies of the polymorphism in different populations fluctuate between 18% and 40%. FABP2 Ala54Thr variant has been associated with an increased fasting insulin concentration, fasting fatty acid oxidation and reduced glucose uptake. This evidence, although not conclusive, sustains an association between FABP-2 genotype and metabolic abnormalities.

Detección de marcadores de malignidad en nódulos tiroideos por transcripción reversa y reacción en cadena de la polimerasa (RT-PCR)

Nodular thyroid disease is a very common disorder witha low frequency of malignancy. The most accurate diagnostic test is fine needle aspiration biopsy(FNAB) of nodules with cytological analysis of the sample. However, this procedure has somelimitations in the diagnosis of follicular and papillary thyroid carcinoma.

Consenso de diagnóstico y manejo de los nódulos tiroideos no palpables

With the availability of new diagnostic techniques, numerous alter-ations are found, whose real importance for health is uncertain. The term «incidentalomas», isused for non apparent tumors found in diagnostic procedures. In Endocrinology, the incidentalfinding of thyroid nodules is common. The occurrence of those incidental nodules requires a re-view of the «classical» statements for the management of palpable nodules. The most important is-sue is to rule out the presence of cancer. The Chilean Society of Endocrinology, Metabolism andNutrition appointed a group of experts to generate a consensus on the management of non palpa-ble nodules. These experts reviewed international literature, and the local experience, analyzedthe value of thyroid ultrasound examination and the efficiency of fine needle aspiration biopsy.This consensus is a clinical guide for the management of non palpable thyroid nodules, consider-ing that a unique and optimal approach is still lacking (Rev Med Chile 2004; 132: 1249-55).(

Atypical antipsychotic induced weight gain and metabolic disorders

The advent of new antipsychotic drugs has improved the treatment of schizophrenic patients as well as those suffering from other severe psychiatric disorders. Its widespread use, however, has been associated to the development of obesity and metabolic disturbances such as diabetes mellitus, dyslipidemia and increased coronary risk. This has caused a serious concern, due to the high cardiovascular mortality that prematurely affects these patients. The etiology of these abnormalities is still a matter of debate, although it is generally believed that the new antipsychotic drugs have a control stimulating effect on appetite, and their use is associated to an increased level of cortisol and to an insulin-resistance state. In addition, there is an increase in inflammatory mediator and cytokine production, induced by the pathophysiology of the schizophrenic process itself and also caused by the direct action of the antipsichotic drugs. In spite of the mounting evidence, the metabolic management of these patients is still dencient. A ciose follow-up in the initial stages of the antipsychotic treatment is recommended, as well as giving advice about diet and physical exercise. Finally, when obesity or other conditions associated to metabolic syndrome appear, the recommendation is to switch to drugs with less secondary effects or to add adjuvant medications to improve the overall evolution of these patients.

PREVENCIÓN DE DIABETES MELLITUS TIPO 2

La Diabetes Mellitus tipo 2 presenta una importante morbilidad y mortalidad y una incidencia esta en aumento, que se asocia al aumento observado en la prevalencia de la obesidad. Diversas medidas han sido evaluadas con el fin de retrasar o prevenir su aparicion, entre las cuales se incluyen cambios en el estilo de vida, farmacos insulinosensibilizadores, e inhibidores de la absorcion de carbohidratos y lipidos, con resultados esperanzadores. En la actualidad, los cambios en el estilo de vida, entendidos en el contexto de un apoyo multidisciplinario al paciente, constituyen la intervencion de mayor impacto. Por otro lado, diversas clases de farmacos empleados en estudios de prevencion de eventos cardiovasculares han demostrado cierto efecto en retrasar o prevenir la aparicion de Diabetes Mellitus tipo 2, lo cual abre un nuevo escenario para los estudios que se desarrollaran en el mediano plazo

Tratamiento del hipertiroidismo con radioyodo: efecto de la dosis administrada sobre la función tiroidea y complicaciones asociadas

BACKGROUND Radio-iodine is a definite therapy for Graves disease hyperthyroidism. However, the optimal dosage is still debatable. AIM To assess the effects of different radioiodine doses on thyroid function and complications in patients with hyperthyroidism. MATERIAL AND METHODS A retrospective analysis of 139 patients with hyperthyroidism, treated with ratio-iodine between 1988 and 1998. Radio iodine dose used was classified as low (< 10 mCi), intermediate (10-14.9 mCi) or high (> or = 15 mCi). RESULTS Thirty-five patients were treated with low doses, 33 with intermediate doses and 71 with high doses. There were no differences between these patients in age, disease severity, frequency of post treatment euthyroidism or complications. Patients treated with low doses had a higher frequency of persistent hyperthyroidism than patients treated with high doses (25.7 and 4.2% respectively, p < 0.001). Likewise, the frequency of subsequent hypothyroidism was 60% in patients treated with low doses and 84.5% of those with high doses, in whom it also appeared earlier. Associated complications were clinically irrelevant. In seven patients, Graves ophthalmopathy progressed after treatment, but this progression was not associated with the dose used. CONCLUSIONS Radio iodine in high doses is useful, safe and effective for the treatment of Graves hyperthyroidism.

Análisis de factores de agresividad de microcarcinoma papilar de tiroides

Resumen es: Introduccion: Los factores de riesgo que determinan una conducta agresiva de microcarcinoma papilar de tiroides (MCPT) no se conocen. Nuestra hipotesis e...