Mejora en la sensibilidad a la insulina con un programa intensivo de cambio en el estilo de vida para control de obesidad en niños y adolescentes en el primer nivel de atención

El objetivo del estudio fue evaluar el efecto de un programa intensivo de cambio en el estilo de vida para el control de peso sobre la sensibilidad a la insulina en niños y adolescentes en el primer nivel de atención. El estudio incluyó a 42 niños y adolescentes de 9 a17 años (n=23 grupo intensivo, n=19 grupo control) que participaron en un estudio clínico aleatorizado para el tratamiento de obesidad. El programa intensivo de cambio en el estilo de vida incluyó consultas mensuales con el médico del primer nivel de atención, asesoría dietética con el nutriólogo (semanal los primeros 3 meses y luego mensual) y 12 sesiones grupales en un protocolo de cambio de conducta. El grupo control incluyó solamente las consultas médicas mensuales. La sensibilidad a la insulina se estimó por el índice de sensibilidad a la insulina (ISI(0,120)) al inicio y a los 6 meses de intervención. Los niños y adolescentes del programa intensivo mostraron un mayor efecto en la sensibilidad a la insulina a los 6 meses en comparación al grupo control ([media ± DE], + 46.8 ± 56 vs. + 5.6 ± 47, diferencia 41.2 [IC 95%, 8.5, 73.9], p= 0.01) y 65% lograron aumentar la sensibilidad a la insulina >9 unidades vs. 32% en el grupo control (p=0.03). Este estudio muestra evidencia preliminar que un programa intensivo de cambio en el estilo de vida puede ser un modelo alternativo para mejorar la sensibilidad a la insulina en los niños y adolescentes con obesidad en el primer nivel de atención.

Improvement of insulin sensitivity after an intensive lifestyle program for youth´s weight management in the primary care. The aim of this study was to evaluate an intensive lifestyle intervention for weight management among youth in a primary care setting on insulin sensibility, compared to a control group. The study included 42 youths 9-17 years old (n=23 intensive lifestyle intervention, n=19 control group) who completed a randomized trial for weight management in a primary care setting which included an oral glucose tolerance test. The intensive lifestyle intervention included monthly consultations with the primary care physician, nutrition counseling with a registered dietitian (weekly first 3 months and then monthly) and 12 group sessions in a behavioral change protocol. The control group attended monthly consultations with the primary care physician. Insulin sensitivity was estimated by the Insulin Sensitivity Index ISI(0,120) at baseline and 6 months posttreatment. At 6 months, the mean ± DE, increase in insulin sensitivity was greater in the intensive lifestyle intervention than the control group (+46.8 ± 56 vs. +5.6 ± 47, betweengroup difference 41.2 [CI 95%, 8.5, 73.9], p= 0.01). Sixty five percent of youths on the intensive lifestyle intervention increased insulin sensitivity over 9 units vs. 32% in the control group (p=0.03). This study shows preliminary evidence that an intensive lifestyle intervention program can be an alternative model to improve insulin sensitivity among youths in the primary care setting.

[Improvement of insulin sensitivity after an intensive lifestyle program for youth's weight management in the primary care]. / Mejora en la sensibilidad a la insulina con un programa intensivo de cambio en el estilo de vida para control de obesidad en niños y adolescentes en el primer nivel de atención.

The aim of this study was to evaluate an intensive lifestyle intervention for weight management among youth in a primary care setting on insulin sensibility, compared to a control group. The study included 42 youths 9-17 years old (n=23 intensive lifestyle intervention, n=19 control group) who completed a randomized trial for weight management in a primary care setting which included an oral glucose tolerance test. The intensive lifestyle intervention included monthly consultations with the primary care physician, nutrition counseling with a registered dietitian (weekly first 3 months and then monthly) and 12 group sessions in a behavioral change protocol. The control group attended monthly consultations with the primary care physician. Insulin sensitivity was estimated by the Insulin Sensitivity Index ISI(0,120) at baseline and 6 months posttreatment. At 6 months, the mean +/- DE, increase in insulin sensitivity was greater in the intensive lifestyle intervention than the control group (+46.8 +/- 56 vs. +5.6 +/- 47, between-group difference 41.2 [CI 95%, 8.5, 73.9], p = 0.01): Sixty five percent of youths on the intensive lifestyle intervention increased insulin sensitivity over 9 units vs. 32% in the control group (p=0.03). This study shows preliminary evidence that an intensive lifestyle intervention program can be an alternative model to improve insulin sensitivity among youths in the primary care setting.

Energetic consequences of mild Giardia intestinalis infestation in Mexican children.

This study explored the effects of mild infestation with Giardia on energy intake and expenditure at rest and in activity in an urban Mexican population. Ten boys aged 6-10 y living in low-income sectors in northwest Mexico who had Giardia infestation were recruited. Energy intake, basal metabolic rate (BMR), and total free-living expenditure (TEE) measured by the doubly labeled water method were determined for 7 d during both infestation and after treatment. There was no significant difference in recorded energy intake between the two periods (7.76 and 7.70 MJ/d; P = 0.847). BMR showed no significant change in response to treatment; values were 4.79 and 4.86 MJ/d (P = 0.03). The mean TEE increased by almost 1 MJ/d in the Giardia-free period. This increase was observed in 8 of the 10 subjects; however, the overall change was not statistically significant (P = 0.08).

HGH isoforms: cDNA expression, adipogenic activity and production in cell culture.

We have isolated, cloned and achieved functional expression of the cDNAs for both 22 kDa and 20 kDa human growth hormone (hGH) isoforms. A selective cDNA cloning strategy was used to preferentially and simultaneously obtain both hGH 22 kDa and hGH 20 kDa cDNAs. These were used to construct minigenes which were subcloned into two eukaryotic expression vectors and then introduced transiently in COS-7 cells and stably into CHO cells in culture. Transfection assays in COS-7 cells of both minigenes allowed the detection of the secreted hGH 22 kDa and hGH 20 kDa. These hGHs isoforms secreted into COS-7 medium were able to specifically promote differentiation of 3T3-F442A preadipocytes to adipose cells. Adipocyte differentiation was quantitated by Oil Red O triacylglycerol staining or glycerophosphate dehydrogenase activity. Furthermore, stable CHO cell lines have been derived that produce these hGH isoforms.

New vectors for the efficient expression of mammalian genes in cultured cells.

We have constructed a new pair of plasmid vectors for the efficient expression of mammalian genes. The first of the new plasmids, pAVE1, was derived from pCMVcat [Foecking and Hofstetter, Gene 45 (1986) 101-105] by replacing the chloramphenicol acetyltransferase-encoding sequences in the latter for a multiple cloning site. Since it possesses the powerful enhancer-promoter unit of the immediate early gene of human cytomegalovirus, pAVE1 is ideal for the expression of mammalian genes. The second expression vector, pAVE2, resulted when the 3'-end flanking region from the human growth hormone-encoding gene (hGH) was incorporated in pAVE1. This region provides sequences for 3'-end processing and polyadenylation of primary transcripts. Thus, pAVE2 is suitable for expression of cDNAs in cultured cells, where introns have little effect on gene expression. To test our new vectors, we inserted the structural region of the chromosomal hGH gene into pAVE1, and its cDNA into pAVE2. By independently transfecting the resulting recombinant plasmids into COS-7 cells, we have achieved high levels of hGH transient expression with both vectors.