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Unlabelled: Identification of congenital adrenal hyperplasia by measurement of blood-spot 17-hydroxyprogesterone., Introduction: 21-hydroxylase deficiency (21-OHD) is the most common cause of congenital adrenal hyperplasia (CAH). The simplest way to diagnose the disease is the measurement of 17-hydroxyprogesterone level in the serum., Aims: The aim of the study was to analyze the clinical advantages of a centralized diagnostic strategy in Hungary using measurement of 17-hydroxyprogesterone in dried blood spots., Methods: During a 20 years period blood-spot samples of 1837 patients suspected to have CAH have been investigated., Results: 185 patients proved to have CAH (classic 21-OHD 155; NCAH 27; 11beta-OHD 3 patients). A national database for CAH was set up by collecting further information about CAH patients in the country. Based on the frequency of the disease in girls during the nineties, the incidence of classical 21-OHD was calculated to be 1:11,147 in Hungary., Conclusions: Early diagnosis, optimal medical and surgical treatment, and attention to compliance may lead to further decrease in morbidity and mortality of CAH patients.

Unlabelled: The aim of this study was to assess the effectivity of the identification of patients with congenital adrenal hyperplasia (CAH) in Hungary in the absence of systematic neonatal screening and to estimate the incidence. Dried blood-spot samples of patients clinically suspected at any age to have CAH were collected between 1978 and 1998 throughout the whole country. 17-Hydroxyprogesterone (17-OHP) was measured by radioimmunoassay. Age-specific cut-offs were used. The effectivity of the system was retrospectively assessed. Additional cases were sought to assess the overall incidence of CAH in Hungary. Among the 1,837 patients investigated, 185 cases of CAH were identified. The overall effectivity was 94.7%. The sensitivity and the specificity were 98.9% and 94.2%, respectively. Salt-wasting (SW) boys were, on average, diagnosed 2 weeks later than SW girls, while both boys and girls with the simple virilising (SV) form were diagnosed at similar ages (2 versus 2.5 years). An additional 19 cases were diagnosed during the study period using other methods (plasma and urinary steroid profiles without blood-spot 17-OHP measurements). The incidence of classical CAH in Hungary was 1:14,300 (CI 95% between 1:12,450 and 1:16,795). Presuming that the incidence of CAH is the same among boys and girls, one can calculate that the diagnosis was missed in 24 boys (2 SW, 22 SV)., Conclusion: it is possible to identify the vast majority of classical cases of congenital adrenal hyperplasia without a neonatal mass screening programme. However, a significant number of boys with the simple virilising form missed whereas both salt-wasting boys and girls are diagnosed safely.

Objective: To test agent and cell-type specificity in insulin resistance induced by prolonged exposure to HIV protease inhibitors (HPI), and to assess its relation to the direct, short-term inhibition of insulin-stimulated glucose uptake., Methods: Following prolonged (18 h) and short (5-10 min) exposure to HPI, insulin-stimulated glucose transport, protein kinase B (PKB) phosphorylation, and GLUT4 translocation were evaluated in 3T3-L1 adipocytes, fibroblasts, L6 myotubes, and L6 cells overexpressing a myc tag on the first exofacial loop of GLUT4 or GLUT1., Results: Prolonged exposure of 3T3-L1 adipocytes to nelfinavir, but not to indinavir or saquinavir, resulted in increased basal lipolysis but decreased insulin-stimulated glucose transport and PKB phosphorylation. In addition, impaired insulin-stimulated glucose uptake and PKB phosphorylation were also observed in the skeletal muscle cell line L6, and in 3T3-L1 fibroblasts. Interestingly, this coincided with increased basal glucose uptake as well as with elevated total-membrane glucose transporter GLUT1 protein content. In contrast to these unique effects of nelfinavir, the mere presence of any of the agents in the 5 min transport assay inhibited insulin-stimulated glucose-uptake activity. This appeared to be caused by direct and specific interaction of the drugs with GLUT4 fully assembled at the plasma membrane, since insulin-stimulated cell-surface exposure of an exofacial myc epitope on GLUT4 was normal., Conclusions: Independent mechanisms for HPI-induced insulin resistance exist: prolonged exposure to nelfinavir interferes with insulin signaling and alters cellular metabolism of adipocytes and muscle cells, whereas a direct inhibitory effect on insulin-stimulated glucose uptake may occurs through specific interaction of HPI with GLUT4.

Hyperglycemia and hyperinsulinemia are cardinal features of acquired insulin resistance. In adipose cell cultures, high glucose and insulin cause insulin resistance of glucose uptake, but because of altered GLUT4 expression and contribution of GLUT1 to glucose uptake, the basis of insulin resistance could not be ascertained. Here we show that GLUT4 determines glucose uptake in L6 myotubes stably overexpressing myc-tagged GLUT4. Preincubation for 24 h with high glucose and insulin (high Glc/Ins) reduced insulin-stimulated GLUT4 translocation by 50%, without affecting GLUT4 expression. Insulin receptor and insulin receptor substrate-1 tyrosine phosphorylation, phosphatidylinositol 3-kinase activation, and Akt phosphorylation also diminished, as did insulin-mediated glucose uptake. However, basal glucose uptake rose by 40% without any gain in surface GLUT4. High Glc/Ins elevated basal p38 mitogen-activated protein kinase (MAPK) phosphorylation and activity, and a short inhibition of p38 MAPK with SB202190 corrected the rise in basal glucose uptake, suggesting that p38 MAPK activity contributes to this rise. We propose that in a cellular model of skeletal muscle, chronic exposure to high Glc/Ins reduced the acute, insulin-elicited GLUT4 translocation. In addition, basal state GLUT4 activity was augmented to partially compensate for the translocation defect, resulting in a more robust glucose uptake than what would be predicted from the amount of cell surface GLUT4 alone.