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Objectives. Turner syndrome (TS) is associated with congenital cardiovascular defects (CCVDs), most commonly bicuspid aortic valve (BAV) and aortic coarctation (COARC), congenital renal anomalies, and fetal lymphedema. It has been theorized that compressive or obstructive effects of fetal lymphedema may actually cause cardiovascular and renal dysmorphogenesis in TS. The objective of this study was to determine whether there is a specific association between a history of fetal lymphedema and CCVDs in monosomy X, or TS, independent of karyotype or general severity of the phenotype. Methods. This was a prospective study of 134 girls and women who have TS (mean age: 30 years) and were clinically evaluated for evidence of fetal lymphedema, classified as central (signified by the presence of neck webbing) or peripheral (current or perinatal, or dysplastic fingernails). The presence of BAV and/or COARC was detected by magnetic resonance imaging combined with echocardiography, and renal anomalies were determined by ultrasound. Results. There is a strong association between developmental central lymphedema, signified by neck webbing, and the presence of BAV ([chi square] = 10) and COARC ([chi square] = 8). The association between webbed neck and CCVDs was independent of karyotype. There was, in contrast, no significant association between renal anomalies and webbed neck or CCVDs. Conclusions. The strong, statistically significant association between neck webbing and the presence of BAV and COARC in TS suggests a pathogenetic connection between fetal lymphatic obstruction and defective aortic development. The presence of neck webbing in TS should alert the clinician to the possibility of congenital cardiovascular defects. Pediatrics 2005;115:732-735; X-chromosome, aortic coarctation, bicuspid aortic valve, lymphedema., ABBREVIATIONS. CCVD, congenital cardiovascular defect; BAV, bicuspid aortic valve; COARC, coarctation; TS, Turner syndrome. Congenital cardiovascular defects (CCVDs), including most commonly bicuspid aortic valve (BAV) and coarctation of the aorta [...]

Insulin-like growth factor (IGF-1) is essential for cellular metabolism and proliferation. Elevated dietary protein results in increased renal IGF-1 synthesis with corresponding decrease in IGF binding protein 1 (IGF BP-1) in medullary thick ascending limb (MTAL) epithelial cells. The local autocrine or paracrine action of IGF-1 results in proliferation of MTAL epithelial cells.

The utilization of in situ hybridization histochemistry for the characterization of CHIP28 mRNA developmental gene expression and tissue location in rats is discussed. Red cells were taken from fetal, postnatal and mature rats and its antibodies were subjected to Western and Northern blot analysis. The relation of CHIP28 gene expression to protein biosynthesis in diverse tissues at certain developmental stages was established.

Results of a study to to evaluate and compare the Norwood procedure with a modified Blalock-Taussig (MBT) shunt as against the right ventrical-pulmonary artery (RVPA) shunt as a form of treatment for single-ventricle lesions in infants with hypoplastic heart syndrome or related anomalies have revealed that in such cases, transplant-free survival at 12 months was better with RVPA, and after 12 months there was no significant difference between the RVPA and MBT shunts. The higher survival rate has highlighted the need to develop the knowledge and resources to provide essential long-term follow-up and support for these children and their families.

The role of insulin-like growth factor I (IGF-I) in myelin regeneration was studied using cuprizone to produce demyelinating lesions in the brain areas of cuprizone-fed mice. The levels of IGF-I and its receptors were then examined atboth genetic and peptide levels. The results showed that IGF-I expression was induced in astrocytes located at the demyelinated lesions. This expression decreased during recovery. Furthermore, there was also an increase in oligodendroglial IGF-I receptor expression during early recovery. The results suggest that IGF-I functions as a diffusible element that stimulates oligodendroglial-mediated activity towards myelin regeneration.

The brain has enormous anabolic needs during early postnatal development. This study presents multiple lines of evidence showing that endogenous brain insulin-like growth factor 1 (Igf1) serves an essential, insulin-like role in promoting neuronal glucose utilization and growth during this period. Brain 2-deoxy-D- [1-[sup.14]C]glucose uptake parallels Igf1 expression in wild-type mice and is profoundly reduced in Igf1-/- mice, particularly in those structures where Igf1 is normally most highly expressed. 2-Deoxy-D-[1-[sup.14]C]glucose is significantly reduced in synaptosomes prepared from Igf1-/- brains, and the deficit is corrected by inclusion of Igf1 in the incubation medium. The serine/threonine kinase Akt/ PKB is a major target of insulin-signaling in the regulation of glucose transport via the facilitative glucose transporter (GLUT4) and glycogen synthesis in peripheral tissues. Phosphorylation of Akt and GLUT4 expression are reduced in Igf1-/- neurons. Phosphorylation of glycogen synthase kinase 3[Beta] and glycogen accumulation also are reduced in Igf1-/- neurons. These data support the hypothesis that endogenous brain Igf1 serves an anabolic, insulin-like role in developing brain metabolism. mental retardation | glycogen synthase kinase | glucose transporter | GLUT4 | Akt

BACKGROUND. We recently reported that electrocardiographic abnormalities are common in adults with monosomy X (Turner syndrome), but this issue has not been investigated in girls with Turner syndrome. PATIENTS AND METHODS. We analyzed electrocardiograms in 78 girls with Turner syndrome and 50 age-matched control girls. The girls with Turner syndrome had additional cardiac and metabolic evaluations. RESULTS. Girls with Turner syndrome were more likely to demonstrate [greater than or equal to] 1 electrocardiographic findings including right axis deviation, right ventricular hypertrophy, accelerated atrioventricular conduction, T-wave abnormalities, and a prolonged rate-corrected QT interval. The right-sided findings were associated with partial anomalous pulmonary venous connection, but the etiology of the other findings remains unknown. The rate-corrected QT interval was significantly longer in girls with Turner syndrome (431 [+ or -] 22 vs 407 [+ or -] 21 milliseconds). Twenty-eight girls with Turner syndrome but only 2 controls had a rate-corrected QT interval above the reference range. We found no correlation between body habitus, cardiac dimensions, or metabolic parameters and the rate-corrected QT interval duration in girls with Turner syndrome. CONCLUSIONS. Cardiac conduction and repolarization abnormalities seem to affect both young girls and adults with Turner syndrome equally, suggesting that electrophysiologic defects are intrinsic to the syndrome and indicating that electrocardiogram analysis should be included in evaluating and monitoring even the youngest patients with Turner syndrome. Attention to the rate-corrected QT interval is important, because some common medications may further prolong this interval and increase the risk of arrhythmias. KEYWORDS. electrophysiology, Turner syndrome, heart disease, long QT. URL: www.pediatrics.org/cgi/doi/10.1542/peds.2006-0776