Metástasis cerebral de carcinoma diferenciado del tiroides / Brain metastases of a differentiated thyroid cancer: report of one case

Brain metastases are observed in approximately 1 percent of patients with differentiated thyroid cancer. We report a 56 years old woman subjected to a thyroidectomy due to a follicular thyroid cancer with lymph node involvement. The patient also received 79 mCi of radioiodine and levothyroxine was started. One year later a local relapse and lung dissemination was found. The patient was subjected to a surgical neck exploration and radioiodine in a dose of 250 mCi was given again. One year after this episode, a new local relapse was diagnosed and lung metastases increased in size and number. The patient presented a left hemiparesis and a brain CAT scan and magnetic resonance imaging showed multiple metastatic lesions. The patient was considered intractable and died eight months later.

Valores normales de captación de 131Yodo de 2 y 24 horas / Normal 131Iodine uptake values at 2 ano 24 hours

Background: Radiolabeled iodine uptake is a useful tool in the study of thyroid diseases. Aim: To obtain normal values for 131 Iodine thyroid uptake in healthy volunteers. Material and methods: A total of 105 subjects were included (52 males and 53 females), with a mean age of 45 years (range: 20 to 68, evenly distributed in decades). A questionnaire was applied and a clinical examination was performed to rule out endocrine diseases. Serum TSH and anti-thyroperoxidase antibodies were also measured. The oral 131I dose was 5-10 fiCi, and a Thyrad equipment was used for measurements at 2 and 24 h. Results: Mean global iodine uptake was 5.5 percent±1.8 percent (range: 2.3-12.0) at 2 h and 16.2±4.8 percent (range: 6.5-30.1) at 24 h. The values at 2 h among women and men were 6.0±1.8 and 4.9±1.6 percent, respectively, (p <0.02). At 24 h, the figures were 17.3±4.5 and 15.0±4.9 percent, respectively (p =0.01). Compared to their younger counterparts, radioactive iodine uptake was lower among volunteers older than 40 years, at 2 h (5.0±1.7 and 6.0±1.8, respectively, p <0.02) and at 24 h (14.9±4.4 and 17.6±4.9 percent, respectively, p <0.01). Conclusions: Normal thyroid uptake values in adults are influenced bygender and age. Normal thyroid iodine uptake values are slightly higher in females. Iodine thyroid uptake values decrease slightly in subjects aged more than 40years.

Polimorfismo de la proteína ligante de ácidos grasos intestinal (FABP2), obesidad e insulina resistencia / Fatty acid binding protein 2 (FABP-2) polymorphism, obesity and insulin resistance

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.

La macroprolactina, diagnóstico diferencial de la hiperprolactinemia / The macroprolactina, differential diagnosis of the hyperprolactinaemia

La macroprolactina es una isoforma de la prolactina (PRL) humana que se encuentra en escasa proporción en el plasma y que en algunos pacientes se puede encontrar anormalmente elevada, causando hiperprolactinemia, que puede presentarse como asintomática, pero también presentar sintomatología dada por el exceso de prolactina, también ha sido relacionada a adenomas hipofisiarios. Por esta causa es necesario contar con métodos confiables para su detección y medición. El origen de esta macromolécula, patogenia, regulación hormonal e historia natural aun no está esclarecido, se postula que corresponde a un complejo antigénico IgG-PRL, con bioactibidad reducida.El Gold Standard para la determinación de la macroprolactina es la Cromatografía de filtración en gel, pero su uso se restringe a la investigación por su alto costo y tiempo de desarrollo. Existen otros métodos para su detección, siendo hasta ahora el de precipitación por Polietilenglicol el más aceptado.

Macroprolactin is an isoform of human prolactin (PRL) existing in low doses in plasma. In some patients, prolactine can be found in higher proportion, causing hyperprolactinaemia, in asyntomaticor symptomatic form. This abnormality has been also related to hypophysis adenome, doing necessary to count on reliable methods for its detection and measurement. The origin of this macromolecule, patogenia, hormonal regulation and natural history are not even clear, an antigenic complex IgG-PRL with reduced bioactivity is proposed. The Gold Standard for determination of macroprolactin is gel filtration chromatography, but its high costs and slowness restricts its use toresearch. Other methods for its detection already exist, the Polyethylene glycol precipitation is beingmostly accepted.