Effect of the parental origin of the X-chromosome on the clinical features, associated complications, the two-year-response to growth hormone (rhGH) and the biochemical profile in patients with turner syndrome.

BACKGROUND: It is possible that genes on the X chromosome are expressed differently depending of its parental origin. The objective of this study was to determine the influence of the parental origin of the X-chromosome on phenotypic variability, response to rhGH and on the biochemical profile of TS patients. METHODS: This was a cross-sectional multicenter correlational study carried out over three years in six Latin-American university hospitals. Unrelated 45,X TS patients (n = 93; 18.3 ± 8.5 years )) were evaluated. A subgroup (n = 34) of the patients were prospectively treated with rhGH over two years. DNA profiles of patients and their mothers were compared to determine the parental origin of the retained X-chromosome through 10 polymorphic X-chromosome-STRs. The association with clinical features, biochemical profiles and anthropometric data at the beginning and after two years of rhGH treatment was determined. RESULTS: Seventy two percent of patients retained the maternal X chromosome (Xm). A trend towards significance between maternal height and patients final height (p ≤ 0.07) in 45,Xm subjects was observed. There was no correlation between paternal height and patient height. No differences were detected between both groups in regard to dysmorphic features, classical malformations or increase in the height-SDS after rhGH. There were higher levels of triglycerides, total and LDL cholesterol in patients >20 years who retained the Xm. CONCLUSIONS: The parental origin of the retained X chromosome may influence lipid metabolism in TS patients, but its effect on growth seems to be minimal. No parental-origin-effect on the phenotypic features, associated anomalies and on the growth response to rhGH was found in 45,X TS individuals.

Prevalencia de complicaciones microvasculares en niños y adolescentes con diabetes mellitus tipo 1: asociación con control metabólico, edad y duración de la enfermedad

Objetivo: determinar la frecuencia de complicaciones microvasculares (CM) en niños y adolescentes con diabetes mellitus tipo 1 (DM1), y su asociación con control metabólico, edad y tiempo de evolución. Métodos: se revisaron 253 historias de pacientes con DM1 (2004-2006). Se recolectó: edad, sexo, estadio puberal, duración de la diabetes, control metabólico (promedio HbA1c) y presencia de retinopatía, nefropatía y neuropatía. Resultados: de los pacientes, 118 eran masculinos (46,6%) y 135 femeninos (53,4%), 8,7% preescolares, 31,7% escolares y 59,6% adolescentes. El 23,2% tenía buen control metabólico, el 76,8% mal control. Se estudió la presencia de complicaciones en 116 pacientes, 61 (52,6%) presentaron alteración, 4 (3,5%) tuvieron retinopatía, 57 (49,1%) nefropatía y 26 (22,4%) neuropatía. Las complicaciones mostraron asociación significativa con la duración de la enfermedad (p<0,003), la edad (p<0,009), el desarrollo puberal (p<0,007) y fueron más frecuentes en los pacientes con mal control (no significativo). La edad fue la variable explicativa mas importante de la presentación de complicaciones (R2: 0,200; RRI: 1,227; IC: 1,108 a 1,358; p=0,0001). Conclusión: las CM en este grupo de pacientes con DM1 tuvieron una prevalencia similar a la reportada en la literatura, y se asociaron con mayor duración de la enfermedad y mayor edad. Se deben proponer estrategias para mejorar el control metabólico.

Objective: to determine the frequency of microvascular complications (MC) in children and adolescents with type 1 diabetes mellitus (DM1), and its association with metabolic control, age and time of evolution. Methods: records of 253 patients with DM1 (2004-2006) were reviewed. Age, sex, pubertal status, duration of diabetes, metabolic control (mean HbA1c) and presence of MC (retinopathy, nephropathy and neuropathy) were collected. Results: of the patients, 118 were male (46.6%) and 135 female (53.4%), 8.7% preschoolers, 31.7% schoolchildren and 59.6% adolescents. Good metabolic control was observed in 23.2% and poor control in 76.8%. The presence of complications was studied in 116 patients, 61 (52.6%) showed alterations, 4 (3.5%) had retinopathy, 57 (49.1%) nephropathy and 26 (22.4%) neuropathy. Complications were significantly associated with disease duration (p <0.003), age (p <0.009), pubertal development (p <0.007) and were more common in patients with poor control (not significant). Age was the most important explanatory variable of the presence of complications (R2: 0.200; Odd’s ratio: 1.227, IC: 1.108 to 1.358, p=0.0001). Conclusion: the MC in this group of patients with DM1 had a prevalence similar to that reported in the literature, and were associated with longer duration of disease and older age. It should propose strategies for improving metabolic control.

Limited Weight Loss or Simply No Weight Gain following Lifestyle-Only Intervention Tends to Redistribute Body Fat, to Decrease Lipid Concentrations, and to Improve Parameters of Insulin Sensitivity in Obese Children.

Objectives. To investigate whether lifestyle-only intervention in obese children who maintain or lose a modest amount of weight redistributes parameters of body composition and reverses metabolic abnormalities. Study Design. Clinical, anthropometric, and metabolic parameters were assessed in 111 overweight or obese children (CA of 11.3 ± 2.8 years; 63 females and 48 males), during 8 months of lifestyle intervention. Patients maintained or lost weight (1-5%) (group A; n: 72) or gained weight (group B). Results. Group A patients presented with a decrease in systolic blood pressure (SBP) and diastolic blood pressure (DBP) (P < .005 and P < .05, resp.), BMI (P < .0001), z-score BMI (P < .0001), waist circumference (P < .0001), fat mass (P < .005), LDL-C (P < .05), Tg/HDL-C ratio (P < .05), fasting and postprandial insulin (P < .005), and HOMA (P < .005), while HDL-C (P < .05) and QUICKI increased (P < .005). Conversely, group B patients had an increase in BMI (P < .0001), waist circumference (P < .005), SBP (P < .005), and in QUICKI (P < .005), while fat mass (P < .05), fasting insulin (P < .05), and HOMA (P < .05) decreased. Lean mass, DBP, lipid concentrations, fasting and postprandial glucose, postprandial insulin, and ultrasensitive C-reactive protein (CRP) remained stable. Conclusions. Obese children who maintain or lose a modest amount of weight following lifestyle-only intervention tend to redistribute their body fat, decrease blood pressure and lipid levels, and to improve parameters of insulin sensitivity.

GHR and VDR genes do not contribute to the growth hormone (GH) response in GH deficient and Turner syndrome patients.

We have prospectively assessed the influence of GHR and VDR gene polymorphisms on the response to rhGH therapy in Venezuelan children with growth hormone deficiency (GHD, n=28) and Turner syndrome (TS, n=25). Clinical data during rhGH treatment were compared in GH and TS patients with different genotypes. PCR amplifications were performed to obtain the genotype frequencies of the polymorphisms. Clinical data at the start of treatment and rhGH doses were indistinguishable among patients with GHD or TS with different GHR or VDR genotypes. After the first two years of rhGH treatment, clinical data in both GHD and TS patients were not different according GHR or VDR genotypes. In addition, there was no significant difference among the subjects when both these genotypes were combined. Gene polymorphisms in low penetrance genes do not contribute to the rhGH therapy response in patients with GHD and TS.

Dislipidemia y disfunción tiroidea en niños y adolescentes con diabetes mellitus tipo 1: Relación con el control metabólico e índice de masa corporal

Objetivo: Determinar la frecuencia de dislipidemia y disfunción tiroidea en niños y adolescentes con DM1, procedentes de la consulta de diabetes del Hospital JM de Los Ríos, y establecer su asociación con el control metabólico y el índice de masa corporal. Métodos: Estudio retrospectivo y descriptivo. Se seleccionaron 253 historias de pacientes con DM1, durante un período de 3 años (2004-2006). Se recolectaron los siguientes datos: edad, sexo, tiempo de evolución de la diabetes, índice de masa corporal (IMC), control metabólico (HbA1c), presencia de anticuerpos antitiroideos, perfil tiroideo y lipídico. Resultados: El 53,4% eran del sexo femenino y 46,6% masculino, 22 (8,7%) preescolares, 80 (31,6%) escolares y 151 (59,7%) adolescentes. El 22,8% tenía buen control metabólico, 77,2% mal control. A mayor edad, el control metabólico empeoraba (p=0,02). Hubo una correlación positiva significativa de la HbA1c, con el IMC y la duración de la DM1. El perfil lipídico se encontró alterado en 69,6% y su frecuencia fue significativamente mayor en los pacientes en mal control. Se observaron valores significativamente más altos de Ct, C-LDL, Tg y relación Tg/C-HDL en los diabéticos mal controlados. Los valores de Ct y de C-LDL fueron significativamente más altos en el grupo con obesidad, en comparación con los normopeso y sobrepeso. Los anticuerpos antitiroideos resultaron positivos en el 12,7%. El 6% presentaron hipotiroidismo y no hubo asociación con la frecuencia de dislipidemia ni el control metabólico. Conclusiones: La frecuencia de dislipidemia e hipofunción tiroidea en los niños y adolescentes con DM1 fue similar a la reportada en la literatura. Se demostró una clara asociación de la dislipidemia con el mal control metabólico y la obesidad. Se recomienda la realización de lipidograma y función tiroidea en pacientes con DM1.

Objetive: To determine the prevalence of thyroid dysfunction and dyslipidemia in children and adolescents with type 1 diabetes mellitus (1DM), from the Children’s Hospital JM de Los Ríos, and its association with metabolic control and body mass index. Methods: A descriptive and retrospective study was done. Data were obtained from the medical records of patients with 1DM, who attended during a period of 3 years (2004 to 2006). The following data were collected: age, sex, duration of diabetes, body mass index (BMI), metabolic control (HbA1c), presence of antithyroid antibodies, thyroid and lipid profile. Results: The 53.4% were female, 46,6% male, twenty two (8.7%) preschoolers, 80 (31.6%) school children and 151 (59.7 %) adolescents. A good metabolic control was observed in 22.8% and poor control in 77.2% of the patients. It was noted that the older the worse metabolic control (p=0.02). There was a significant positive correlation of HbA1c values with BMI and duration of DM1. The 69,6% had some form of dyslipidemia and the frequency of atherogenic lipid profile was significantly higher in patients poorly controlled. Significantly higher values of Ct, C-LDL, triglycerides and Tg/HDL-C ratio were observed in diabetics in poor metabolic control. The values of TC and LDL-C were significantly higher in the obese group compared with normal and overweight subjects. Antithyroid antibodies were positive in 12.7% of the patients. The 6% were hypothyroid and there was not association with the frequency of dyslipidemia or the metabolic control. Conclusion: The frequency of dyslipidemia and hypothyroidism in children and adolescents with 1DM was similar to that reported in the literature. It was demonstrated a clear association of dyslipidemia with poor metabolic control and obesity. We recommend the determination of lipids and thyroid function in patients with type 1 DM.

Distribución de las frecuencias alélicas y genotípicas del polimorfismo GHRd3 en pacientes venezolanos con talla baja

Objetivos. La deleción (GHRd3) o inserción (GHRfl) del exón 3 es un polimorfismo común en el gen del receptor de la hormona de crecimiento (GHR) en los seres humanos. La presencia del alelo GHRd3 se ha asociado con el grado de respuesta de terapia con Hormona de Crecimiento Recombinante Humana (rhGH). El objetivo de este estudio fue determinar las frecuencias alélicas y genotípicas de este polimorfismo en un grupo de 69 niños venezolanos con talla baja que estaban recibiendo rhGH. Métodos. Se extrajo DNA a través de la técnica del método combinado Fenol/Sevag e Inorgánica. Se determinó el genotipo del exón 3 del gen GHR usando tanto PCR- monoplex como PCR-multiplex. Resultados. Entre los pacientes con talla baja la frecuencia genotípica se distribuyó de la siguiente manera: GHRfl/GHRfl (55%) GHRfl/GHRd3 (35%) y GHRd3/GHRd3 (10%) y la frecuencia alélica fue de 0,27 para GHRd3 y 0,73 para GHRfl. Para el grupo testigo la frecuencia genotípica se distribuyo así: GHRfl/GHRfl (56%), GHRfl/ GHRd3 (30%) y GHRd3/GHRd3 (14%) y la frecuencia alélica era de 0,29 para GHRd3 y 0,71 para GHRfl. Las características clínicas basales de los pacientes con talla baja eran similares entre los diferentes genotipos encontrados en el grupo de estudio. Conclusiones. La proporción del genotipo y los alelos del gen GHR fueron similares entre el grupo testigo y los pacientes con talla baja, lo que traduce que la etiología de la talla baja no obedece a este polimorfismo.

Objective. The deletion (GHRd3) or insertion (GHRfl) of exon 3 is a common polymorphism in the receptor growth hormone gene (GHR) in humans. The presence of the allele GHRd3 has been associated with the degree of responsiveness to therapy with recombinant human Growth Hormone (rhGH). The aim of this study was to determine the genotypic and allele frequencies of this polymorphism in a group of 69 Venezuelan children with short stature who were receiving rhGH. Methods. Genomic DNA was extracted from blood lymphocytes using combined method Fenol/SEVAG + Salting out. The GHR-exon 3 was genotyped using both PCR monoplex and multiplex assays. Results. Among patients with short stature, genotype frequency was distributed as follows: GHRfl/GHRfl (55%), GHRfl/GHRd3 (35%) and GHRd3/GHRd3 (10%) and allele frequency for GHRd3 and GHRfl was 0.27 and 0.73, respectively. For the control group, genotype frequency was distributed as follows: GHRfl/GHRfl (56%), GHRfl/GHRd3 (30%) and GHRd3/GHRd3 (14%) and allele frequency for GHRd3 and GHRfl was 0.29 and 0.71, respectively. The baseline clinical features of patients with short stature were similar among different genotypes found in the study group. Conclusions. The proportion of genotype and allele of the GHR gene were similar between the control group and patients with short stature, which translates that the etiology of short stature is not due to this polymorphism.

Circulating levels of high-sensitivity C-reactive protein and soluble markers of vascular endothelial cell activation in growth hormone-deficient adolescents.

BACKGROUND/AIMS: Significant endothelial dysfunction as determined by lower flow-mediated vasodilation of the brachial artery was recently reported by us in growth hormone-deficient (GHD) adolescents. The circulating concentrations of markers of vascular endothelial cell and platelet activation and their relationship to inflammatory markers have not been previously evaluated in this group of patients. OBJECTIVE: To assess the relationship between circulating levels of high-sensitivity C-reactive protein (CRP) and soluble markers of vascular endothelial cell activation in GHD adolescents. DESIGN/METHODS: Twenty-eight GHD children on GH treatment with a chronological age of 15.7 +/- 2.6 years and 16 untreated GHD adolescents with a chronological age of 16.6 +/- 3.3 years were studied. Concentrations of CRP, as an inflammatory marker, were measured in all patients and the association between CRP and the fasting soluble markers of vascular endothelial cell activation intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E-selectin and P-selectin levels was evaluated. Sixteen healthy adolescents with a mean chronological age of 15.1 +/- 2.2 years served as controls. RESULTS: CRP and P-selectin levels were significantly higher in untreated GHD adolescents than in treated GHD subjects or in healthy controls (p < 0.02), while VCAM-1 concentrations were increased in both untreated and treated GHD adolescents when compared to controls (p < 0.007). E-selectin and ICAM-1 levels were similar in all three groups. CRP was found to be associated with BMI (r: 0.62; p < 0.001), P-selectin (r: 0.43; p < 0.01), E-selectin (r: 0.27; p < 0.03), ICAM-1 (r: 0.23; p < 0.05) and VCAM-1 (r: 0.40; p < 0.001) concentrations in untreated GHD adolescents and with P-selectin (r: 0.88; p < 0.001) and E-selectin (r: 0.29; p < 0.01) in treated GHD subjects. A weak inverse association was observed in a subgroup of patients between brachial artery endothelium-dependent dilation and P-selectin (r: -0.56; p < 0.07). CONCLUSIONS: Low-grade inflammation as manifested by increased circulating levels of CRP seems to be associated with the early activation of vascular endothelial cells in GHD adolescents.