Cardiac atrophy in women following bed rest

Both chronic microgravity exposure and long‐duration bed rest induce cardiac atrophy, which leads to reduced standing stroke volume and orthostatic intolerance. However, despite the fact that women appear to be more susceptible to post‐spaceflight presyncope and orthostatic hypotension than male astronauts, most previous high‐resolution studies of cardiac morphology following microgravity have been performed only in men. Because female athletes have less physiological hypertrophy than male athletes, we reasoned that they also might have altered physiological cardiac atrophy after bed rest. Magnetic resonance imaging was performed in 24 healthy young women (32.1±4 years) to measure left ventricular (LV) and right ventricular (RV) mass, volumes, and morphology accurately before and after 60 days of 6° head‐down tilt (HDT) bed rest. Subjects were matched and then randomly assigned to sedentary bed rest (controls, n=8) or two treatment groups consisting of (1) exercise training using supine treadmill running within lower body negative pressure plus resistive training (n=8), or (2) protein (0.45 g/kg/day increase) plus branched‐chain amino acid (BCAA) (7.2 g/day) supplementation (n=8). After sedentary bed rest without nutritional supplementation, there were significant reductions in LV (96±26–77±25 mL; P=0.03) and RV volumes (104±33–86±25 mL; P=0.02), LV (2.2±0.2–2.0±0.2 g/kg; P=0.003) and RV masses (0.8±0.1–0.6±0.1 g/kg; P<0.001), and the length of the major axis of the LV (90±6–84±7 mm. P<0.001), similar to what has been observed previously in men (8.0%; Perhonen M.A., Franco F., Lane L.D., Buckey J.C., Blomqvist Zerwekh J.E., Peshock R.M., Weatherall P.T., Levine B.D. J Appl Physiol 2001: 91: 645–653). In contrast, there were no significant reductions in LV or RV volumes in the exercise‐trained group, and the length of the major axis was preserved. Moreover, there were significant increases in LV (1.9±0.4–2.3±0.3 g/kg; P<0.001) and RV masses (0.7±0.1–0.8±0.2 g/kg; P=0.002), as well as mean wall thickness (9±2–11±1 mm; P=0.02). The interaction between sedentary and exercise LV and RV masses was highly significant (P<0.0001). Protein and BCAA supplementation led to an intermediate phenotype with no change in LV or RV mass after bed rest, but there remained a significant reduction in LV volume (103±14–80±16 mL; P=0.02) and major‐axis length (91±5–88±7 mm; P=0.003). All subjects lost an equivalent amount of body mass (3.4±0.2 kg control; 3.1±0.04 kg exercise; 2.8±0.1 kg protein). Cardiac atrophy occurs in women similar to men following sedentary 60 days HDT bed rest. However, exercise training and, to a lesser extent, protein supplementation may be potential countermeasures to the cardiac atrophy associated with chronic unloading conditions such as in spaceflight and prolonged bed rest.     

Efficacy of anti-digoxin antibodies in a premature neonate

Through the case report of severe digitalis intoxication in a premature born after 27 weeks of gestation with a birthweight of 800 g, the authors show that anti-digoxin antibodies constitute a very efficacious therapeutic tool which, up to the present, has not been used in prematures.     

Alteration of visual evoked potentials and electroretinograms in Parkinson's disease

A group of 24 patients with Parkinson's disease (PD) with normal fundi and normal visual acuities was examined electrophysiologically. Checkerboard reversal VEPs and ERGs (P-ERGs) at various contrast levels as well as photopic and scotopic luminance ERGs were recorded and compared with an age-matched group of controls. Earlier reported latency increases of the VEPs of the patients were confirmed for patterns of high contrast only. Scotopic and photopic luminance ERGs of the patients showed normal latencies, but at all light intensities the amplitudes of the scotopic and photopic b wave, as well as the amplitudes of the photopic a waves, were significantly reduced, P-ERG amplitudes were reduced at 50% contrast. Identical results were obtained in patients under dopaminergic treatment (n = 17) and in patients who did not receive any treatment (n = 7). These results suggest that alterations occur already at the retinal level where dopamine receptors have been found. Thus the reported changes of the VEP are not caused by the visual cortex alone.     

Early childhood teachers' preparation and the quality of program outcomes

The issue of the preparation of effective teachers becomes more critical for teachers of early childhood programs. It has been hypothesized that better program quality depends on better-educated teachers. The purpose of this investigation was to explore the importance of a high level of education for all early childhood education teachers. This issue has intrigued early childhood researchers and has prompted a large amount of research studies over the past decades. In order to assess the status of this line of inquiry and to provide guidance for future research, a critical analysis of 40 studies on the preparation of early childhood education teachers and the quality of their educational programs that were published within a 15-year (1989-2004) period is presented here. The analysis consisted of literal and allegorical critical analysis and interpretative critical analyses, which generated results in three main areas that focused on the professional development of the teachers, including teachers' professional development, the importance of a Bachelor's Degree and educational standards for early childhood education teachers.     

Antigenic structure of the hexacosapeptide melittin: evidence for three determinants, one with a helical conformation.

ELISA-based epitope analysis was performed using rabbit polyclonal antisera against melittin. Antigenic sites were found at the C-terminus, in the middle section and within the N-terminal helix. Antibodies against the helical segment could discriminate between two faces of the amphiphilic helix. The antigenic sites include the bulk of the melittin hexacosapeptide, which is synonymous with a very high epitope density.     

Sonographic and computerized tomography study of congenital choledochal cyst

In the neonatal period ultrasound and hepatobiliary functional scintigraphy are used to diagnose choledochal cysts. Initial sonography demonstrates hepatobiliary anatomy, hepatobiliary function is assessed by subsequent scintigraphy. The diagnosis can be confirmed by additional computed tomography as shown in this case report.     

Gastric outlet obstruction after long-term prostaglandin administration mimicking hypertrophic pyloric stenosis.

Prostaglandin E1 (PGE1) is widely used in neonates with cyanotic congenital heart disease who depend on the patency of the ductus arteriosus for oxygenation. Side effects of prostaglandin therapy are common and include respiratory depression, generalized flushing, and cardiovascular and neurological effects. Little is known about the complex effects on the gastrointestinal tract. We report on an infant with gastric outlet obstruction after long-term prostaglandin administration. At the age of 1 month, feeding problems developed with projectile vomiting. Ultrasonography showed progressive elongation of the antropyloric channel without wall thickening, which was causing gastric outlet obstruction. Three days after cardiac surgery and cessation of prostaglandin therapy, the infant fed normally and rapidly gained weight. The clinical signs in such patients can mimic hypertrophic pyloric stenosis. Therefore, the sonographic findings should not be confused with pyloric wall thickening to avoid a false diagnosis and unnecessary surgery. The symptoms diminish with cessation of the prostaglandin therapy after a corrective cardiac operation.