Efecto del factor de crecimiento de fibroblastos 21 / Fibroblast growht factor 21 effects over phosphatase SHP-2 expression in Malme-3 cells

Almost 50 percent of Noonan syndrome patients, characterized by short stature, present activating mutations of the citoplasmatic phosphatase SHP-2, which induce hyperactivation of the Ras/MAPK pathway. On the other hand, the fibroblast growth factor 21 (FGF-21), recently suggested as a FGF with “endocrine” function, would affect longitudinal growth inhibiting growth hormone signaling at chondrocytes level. Union and activation of FGF-21 to its receptor is regulated by the co-factor beta Klotho (KLB). Aims: To determine if FGF-21 and/or FGF-21+KLB are able to modify the genetic expression of SHP-2 ina human skin fibroblast cell line (Malme-3). Methods: cells were incubated with or without FGF-21, FGF-21 + KLB. At 12 and 24 hours after induction total RNA was extracted andSHP-2 mRNA levels were determine by quantitative PCR. Expression of GADPH gene was employed for normalization. Results: Incubation with FGF-21 produce a 36 percent (p = < 0,05)increment in SHP-2 expression, which was not modified with KLB co-incubation. Discussion: it is shown by the first time that FGF-21 is able to produce an increase in SHP-2 gene expression in human fibroblast, which was independent of KLB presence...

Síndrome metabólico en niñas púberes con hiperplasia suprarrenal congénita clásica / Metabolic syndrome among puberal girls with classic congenital adrenal hyperplasia

Background: Adult women with adrenal congenital hyperplasia (AH) have a higher risk for insulin resistance, dyslipidemia, hypertension, high body mass index (BMI) and increased body fat. All these factors are associated with cardiovascular risk and metabolic syndrome (MS). Aim: To evaluate the presence of MS in pubertal classic AH girls (CAH) and a control group (C). Material and Methods: We studied 15 pubertal AH patients (12.0 +/- 1.9 years) and 26 controls (11.7+/- 0.3 years) matched by age and tanner stage. Weight, height, BMI, waist/hip ratio, blood pressure and serum lipids were measured. An oral glucose tolerance test (OGTT) and insulin curve was performed in CAH girls whereas in controls basal insulin and glucose were determined. The homeostasis model assessment for insulin resistance (HOMAIR) was calculated. Cook, Ferranti and international diabetes federation (IDF) criteria were used to determine the presence of MS. Results: CAH and C girls had similar BMI (22.0 +/- 5.1 and 20.1 +/- 3.6 kg/m2 respectively; p = 0,11). CAH girls had higher basal blood glucose (80.8 +/- 7.7 and 60.6 +/- 10.6 mg/dl respectively, p < 0.01) and controls had higher triglyceride levels (147.0 +/- 69.3 and 79.7 +/-16.3 mg/dl respectively, p < 0.01) and lower HDL cholesterol levels (45.8 +/- 12.8 and 56.9 +/- 17.5 mg/dl respectively, p = 0.02). According to cook criteria 4 percent of CAH girls and 23 percent of controls has MS. These figures were 14 and 32 percent respectively according to Ferranti criteria and 0 and 5 percent respectively according to IDF criteria. Conclusions: CAH puberal patients do not have a higher prevalence of metabolic syndrome, compared with controls with similar Tanner stage and BMI.

Relación entre el polimorfismo -34 Bp de la región promotora del gen CYP17 con el perfil hormonal y metabólico en mujeres con diabetes mellitus tipo 1 / Relationship of -34 Bp polymorphism in the promoter of Cyp17 gene with hormonal and metabolic profile in women with type 1 diabetes mellitus

The P450c17a enzyme has a central role in ovarian hyperandrogenism, which is a characteristic of polycystic ovary syndrome (PCOS). Several studies have suggested a possible role for the CYP17 gene, which codes for the enzyme P450c17a and the -34bp T-C polymorphism in the development of hyperandrogenism. The presence of the cytosine, know as A2 allele, has been associated with hyperandrogenism in patients with PCOS. Objective: To evaluate the frequency and association of the -34bp polymorphism in the CYP17 gene and determine its association with hormonal and metabolic characteristics in women with DM1. Patients and Methods: The CYP17 polymorphism was studied in 72 DM1 and 71 control women by PCR and RFLP analysis. The CYP17 genetic dosage was compared with the antropometrical characteristics and the serum concentrations of testosterone, androstenedione, DHEAS and 17OH progesterone in women with DM1. Results: Genotype A2/A2 was present in 20.8 percent and 7.1 percent of DM1 and controls, respectively (p = 0,034). Allele A2 was present in 40.3 percent and 27.5 percent of DM1 and healthy women, respectively (p = 0,031). No association between CYP17 genotypes and hormonal or metabolic characteristics was observed. Conclusion: This study shows that the frequency of the A2/A2 genotype was higher in women with DM1 than in the control group. However, no association between the presence of the polymorphism and circulating steroid levels or BMI was observed.

[IGF-I sensitivity in small for gestational age children]. / Sensibilidad a IGF-I en niños pequeños para la edad gestacional.

BACKGROUND: The lack of catch up growth (CUG) in small for gestational age (SGA) children may be related to a reduced sensitivity to insulin growth factor 1 (IGF-I). AIM: To assess the sensitivity to IGF-I in small for gestational age children, measuring basal and post IGF-I nocturnal profile of growth hormone (GH). PATIENTS AND METHODS: We studied 34 prepubertal SGA children aged 4 to 11 years. Twenty three had CUG and 11 did not have CUG. As an IGF-I sensitivity test, nocturnal GH levels were measured every 20 minutes from 23:00 h to 07:00 h, both under baseline conditions and after the administration of a subcutaneous bolus of 1 mg/kg/body weight of the IGF-I + IGFBP-3 complex (Somatokine). RESULTS: At the time of the study, the Z scores for height among children with and without CUG were -1.55 +/- 0.22 and -3.24 +/- 0.28, respectively (p <0.0001). There were no statistical differences between CUG + vs CUG- patients in mean basal GH (6.6 +/- 0.5 and 5.6 +/- 0.6 ng/ml, respectively). After Somatokine administration, mean GH, and the mean GH area under the curve (AUC) decreased significantly in both groups. However, mean overnight GH AUC decreased in all SGA children with CUG, after Somatokine administration, whereas 3 out of 11 SGA children without CUG had an increase in their mean GH AUC in response to Somatokine. CONCLUSIONS: These findings suggest that pituitary sensitivity to IGF-I may be decreased in some SGA children without CUG.

Sensibilidad a IGF-I en niños pequeños para la edad gestacional / IGF-I sensitivity in small for gestational age children

Background: The lack of catch up growth (CUG) in small for gestational age (SGA) children may be related to a reduced sensitivity to insulin growth factor 1 (IGF-I). Aim: To assess the sensitivity to IGF-I in small for gestational age children, measuring basal and post IGF-I nocturnal profile of growth hormone (GH). Patients and methods: We studied 34 prepubertal SGA children aged 4 to 11 years. Twenty three had CUG and 11 did not have CUG. As an IGF-I sensitivity test, nocturnal GH levels were measured every 20 minutes from 23:00 h to 07:00 h, both under baseline conditions and after the administration of a subcutaneous bolus of 1 mg/kg/body weight of the IGF-I + IGFBP-3 complex (Somatokine®). Results: At the time of the study, the Z scores for height among children with and without CUG were -1.55 ± 0.22 and -3.24 ± 0.28, respectively (p <0.0001). There were no statistical differences between CUG + vs CUG- patients in mean basal GH (6.6 ± 0.5 and 5.6 ± 0.6 ng/ml, respectively). After Somatokine® administration, mean GH, and the mean GH area under the curve (AUC) decreased significantly in both groups. However, mean overnight GH AUC decreased in all SGA children with CUG, after Somatokine® administration, whereas 3 out of 11 SGA children without CUG had an increase in their mean GH AUC in response to Somatokine®. Conclusions: These findings suggest that pituitary sensitivity to IGF-I may be decreased in some SGA children without CUG.

Test de estimulación intraarterial selectiva con calcio en el diagnóstico de localización de insulinomas: Casos clínicos / Selective intra arterial calcium stimulation for the localization of insulinomas: Report of two cases

Insulinoma is the most common neuroendocrine tumor. Its clinical manifestations are frequently confounded with neuropsychiatric symptoms, and definitive diagnosis can be delayed for a long time. These tumors are usually small, of less than 2 cm. Thus, their preoperative localization is difficult. We report two patients with a clinical diagnosis of insulinoma, in whom the preoperative imaging study was negative. Both fulfilled diagnostic criteria, with high serum insulin levels in the presence of a blood glucose of less than 45 mg/dl. The imaging study, including abdominal computed tomography and pancreatic endoscopic ultrasonography did not disclose the location of the tumor. A pancreatic angiography with selective stimulation with intra arterial calcium and venous sampling for insulin measurements, was performed in both patients. This test allowed the exact localization of the tumors and their successful excision. A review of other localization diagnostic tests is done (Rev Méd Chile 2004; 132: 71-5).

Bocio y tiroiditis linfocitaria crónica / Goiter and chronic lymphocitic thyroiditis

Se estudiaron 60 pacientes con bocio, de 3 a 16 años de edad, 58 eran mujeres, 38 (63%) de los cuales presentaba dos o más elementos sugerentes de tiroiditis linfocitaria crónica (TLC) (criterio de Fisher) destacando en ellos el compromiso de la función tiroidea 18/38 (47,4%) con hipotiroidismo y 7/38 (18,4%) con hipertiroidismo. Los demás pacientes con bocio difuso, que no cumplían los criterios de Fisher, fueron denominados "bocio no tiroiditis" (37%) y eran eutiroideos en proporción de 95%. En todos los pacientes con probable TLC se detectaron anticuerpos antimicrosomales en títulos relativamente altos. Sólo 32% tenían simultáneamente anticuerpos antimicrosomales y antitiroglobulinas positivos. Entre los 22 pacientes con "bocios no tiroiditis", 6 (28%) tenían anticuerpos antimicrosomales positivos, en títulos bajos (1 x 100 y 1 x 40, respectivamente). En un grupo control de 28 niños de edades similares a los propósitos, sin enfermedades endocrinas ni antecedentes familiares de afecciones tiroideas, sólo 3 (11%) presentaron anticuerpos positivos, en títulos bajos