Prevention and treatment of respiratory syncytial virus bronchiolitis and postbronchiolitic wheezing

Growth factors mediate tissue interactions and regulate a variety of cellular functions that are critical for normal lung development and homeostasis. Besides their involvement in lung pattern formation, growth and cell differentiation during organogenesis, these factors have been also implicated in modulating injury-repair responses of the adult lung. Altered expression of growth factors, such as transforming growth factor β1, vascular endothelial growth factor and epidermal growth factor, and/or their receptors, has been found in a number of pathological lung conditions. In this paper, we discuss the dual role of these molecules in mediating beneficial feedback responses or responses that can further damage lung integrity; we shall also discuss the basis for their prospective use as therapeutic agents.     

Kalign – an accurate and fast multiple sequence alignment algorithm

Background  

The alignment of multiple protein sequences is a fundamental step in the analysis of biological data. It has traditionally been applied to analyzing protein families for conserved motifs, phylogeny, structural properties, and to improve sensitivity in homology searching. The availability of complete genome sequences has increased the demands on multiple sequence alignment (MSA) programs. Current MSA methods suffer from being either too inaccurate or too computationally expensive to be applied effectively in large-scale comparative genomics.     

Treatment of hostile midline back wounds: an extreme approach

The basic principles of successful wound closure remain the same: careful preoperative evaluation, removal of underlying nonviable tissue, and well-vascularized soft-tissue coverage. Many complex or "hostile" back wound closures also require stabilization of the spine and a two-layered wound closure. The use of long arteriovenous fistulas with free tissue transfer provides an additional weapon for the treatment of these complex wounds.     

Diurnal fluctuation in saliva aldosterone concentration

We have measured saliva aldosterone concentration (SA) at frequent intervals in subjects going about their normal daytime activities. Four hourly sampling sufficed to give a reasonable estimate of mean diurnal SA but hourly sampling is necessary if it is desired to study the temporal pattern of SA. In subjects with normal or elevated mean levels, SA fluctuated considerably suggestive of several distinct episodes of aldosterone secretion. Such fluctuations show little correlation with the concentrations in saliva of glucocorticoids (cortisol + cortisone) nor are they consistent with a circadian rhythm of aldosterone secretion. We suggest that they may represent responses to such stimuli as eating, drinking or physical activity, and possibly to other as yet unidentified factors. These observations show the importance of comprehensive diurnal assessment of aldosterone level in physiological and pathological investigations. Because of its non-invasive nature and the high productivity of the assay, measurement of SA is ideally suited for this purpose.     

The effect of exercise on the production and clearance of testosterone in well trained young men

Tritium-labelled testosterone was infused into four well-trained subjects at rest and during one hour of exercise at about 60% of their maximum aerobic power. This exercise regime led to a mean increase of 27% (range 10-51%) in plasma testosterone concentration. At the same time there were significant decreases in the estimated hepatic plasma flow (EHPF) (45%; range 28-67%), metabolic clearance rate of testosterone (MCRT) (29%; range 18-37%) and plasma volume (8.2%; range 3-10%). The production rate of testosterone decreased by 10% (range 9-22%) but this was not statistically significant. The ratio MCRT:EHPF increased in 3 out of 4 subjects in response to exercise but there was considerable inter-subject variation both at rest and during exercise. These findings suggest that the exercise-induced elevation of testosterone level is due solely to the reduction in the rate at which testosterone is cleared from the plasma. The principal cause of the reduction in MCRT is probably the reduction in EHPF but the variation in the ratio MCRT:EHPF suggests that changes in the extrahepatic clearance of testosterone may also be involved.