RESUMEN

Copy number variations (CNVs) are a type of genetic variation involving from 50 base pairs (bps) to millions of bps and, in a general point of view, can include alterations of complete chromosomes. As CNVs mean the gain or loss of DNA sequences, their detection requires specific techniques and analysis. We have developed Easy One-Step Amplification and Labeling for CNV Detection (EOSAL-CNV) by fragment analysis in a DNA sequencer. The procedure is based on a single PCR reaction for amplification and labeling of all fragments included. The protocol includes specific primers for the amplification of the regions of interest with a tail in each of the primers (one for forward and another for the reverse primers) together with primers for tail amplification. One of the primers for tail amplification is labeled with a fluorophore, allowing the amplification and labeling in the same reaction. Combination of several tail pairs and labels allows the detection of DNA fragment by different fluorophores and increases the number of fragments that can be analyzed in one reaction. PCR products can be analyzed without any purification on a DNA sequencer for fragment detection and quantification. Finally, simple and easy calculations allow the detection of fragments with deletions or extra copies. The use of EOSAL-CNV allows simplifying and reducing costs in sample analysis for CNV detection.

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RESUMEN

Background: subclinical hyperthyroidism (SHT) is associated with harmful effects on cardiovascular system, bone metabolism and progression to clinical hyperthyroidism. Loss of weight is a common fact in patients with clinical hyperthyroidism and of particular relevance in elderly patients. Objective: to assess changes in body composition after radioiodine therapy for SHT due to toxic nodular goiter. Subjects and methods: prospective controlled cohort study. Patients with persistent SHT due to toxic nodular goiter were purposed to receive treatment with radioiodine (treatment group) or to delay treatment until the study was over (control group). All treated patients received 555 MBq of 131I. Body composition (lean mass, fat mass and bone mineral content) was determined by dual-energy X-ray absorptiometry (DEXA) at baseline and 12 months after. Results: twenty-nine patients were studied (age 69.5 ± 11.5; 75.9% women; BMI 27.1 ± 5.7 kg/m²; serum thyrotropin (TSH) 0.20 ± 0.21 µUI/mL; serum free thyroxine (T4) 1.01 ± 0.19 ng/dL), 17 belonging to the treatment group and 12 to the control group. Study groups were comparable, although there was a trend for the treatment group to have more fat mass. No longitudinal changes in body composition were noted in either group, except for a trend to gain fat mass. However, when individuals with age > 65 years were selected, only patients who received radioiodine therapy showed a significant increase in body weight (from 64.1 ± 10.0 to 66.9 ± 9.2 kg), BMI (from 27.3 ± 4.8 to 28.7 ± 4.5 kg/m²), fat mass (from 26.1 ± 8.5 to 27.8 ± 7.9 kg), lean mass (from 36.3 ± 0.4 to 37.4 ± 0.4 kg) and skeletal muscle mass index (SMI) (from 6.0 ± 0.6 to 6.3 ± 0.6 kg/m²). Conclusions: treatment of SHT has impact on body composition in subjects older than 65 years. Weight gain reflects increases in fat and, more interestingly, in lean mass (AU)

Introducción: el hipertiroidismo subclínico (HS) se asocia a efectos deletéreos sobre el sistema cardiovascular, el metabolismo óseo y puede progresar a hipertiroidismo clínico. La pérdida de peso es habitual en los pacientes con hipertiroidismo clínico y adquiere especial relevancia en los sujetos añosos. Objetivo: evaluar los cambios en la composición corporal después del tratamiento del HS por bocio nodular con radioyodo. Sujetos y métodos: estudio de cohortes prospectivo controlado. A los pacientes con HS persistente debido a bocio nodular tóxico se les ofreció la opción de recibir tratamiento con radioyodo (grupo tratamiento) o retrasar dicho tratamiento hasta que el estudio hubiera acabado (grupo control). Al final, todos los pacientes recibieron 555 MBq de 131I. La composición corporal (masa magra, masa grasa y contenido mineral óseo) se determinó por absorciometría con rayos X de doble energía (DEXA) al inicio y a los 12 meses. Resultados: se estudiaron 29 pacientes (edad 69,5 ± 11,5; 75,9% mujeres; BMI 27,1 ± 5,7 kg/m²; tirotropina sérica (TSH) 0,20 ± 0,21 µUI/mL; tiroxina libre sérica(T4) 1,01 ± 0,19 ng/dL), 17 pertenecientes al grupo tratamiento y 12 al grupo control. Los grupos de estudio fueron comparables, aunque existía una tendencia del grupo tratamiento a presentar más masa grasa. No se detectaron cambios en la composición corporal en ningún grupo, salvo una tendencia general a ganar masa grasa. Sin embargo, cuando se seleccionaron los individuos con edad > 65 años, sólo los pacientes que recibieron tratamiento con radioyodo mostraron un significativo incremento de peso (de 64,1 ± 10,0 a 66,9 ± 9,2 kg), IMC (de 27,3 ± 4,8 a 28,7 ± 4,5 kg/m²), masa grasa (de 26,1 ± 8,5 a 27,8 ± 7,9 kg), masa magra (de 36,3 ± 0,4 a 37,4 ± 0,4 kg) e índice de masa muscular esquelética (de 6,0 ± 0,6 a 6,3 ± 0,6 kg/m²). Conclusiones: el tratamiento del HS tiene impacto sobre la composición corporal en sujetos mayores de 65 años. La ganancia de peso refleja incrementos en la masa grasa y, lo que es más interesante, en la masa magra (AU)

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