Regulation of growth hormone (GH) bioactivity by a recombinant human GH-binding protein

The in vitro biological effects of serum GH-binding protein (GHBP) were measured in the mouse 3T3-F442A preadipocyte adipogenesis assay during GH stimulation. Coincubation of increasing concentrations of human (h) GH (0.14-4.5 nM) with 4.2 nM recombinant hGHBP-(1-247) in serum-free medium shifted the hGH dose-response curve to the right over the range 0.14-0.9 nM. When the hGH concentration was fixed at 0.45 nM, a dose-dependent inhibition of GH bioactivity was seen over the range of 0.1-11.3 nM GHBP, with an ED50 of 3 nM. The presence of serum had no effect on the inhibitory properties of GHBP. When 2% pooled human serum was added to incubation medium containing 0.45 nM hGH and GHBP (0.6 nM-5.7 nM), the effect of GHBP was again inhibitory, with an ED50 of 1.2 nM. Two percent serum alone was adipogenic, but at this low serum concentration it is likely that some factor other than GH is responsible. In a homologous receptor assay, the binding of [125I]hGH to IM-9 lymphocytes was inhibited in a dose-dependent manner by increasing concentrations of hGHBP in the physiological range, providing further support for the idea that GHBP can regulate the bioactivity of GH by blocking the binding of free GH to target tissues in vivo. Our results suggest that one function of GHBP is to dampen the biological effects of pulsatile GH secretion by reducing free GH during secretory pulses. This effect combined with an increased half-life of circulating GH would have the effect of flattening the hormone secretory profile at the target tissue level.     

A scoping review of time-use research in occupational therapy and occupational science

Background: Time use is a defining interest within occupational therapy and occupational science. This is evident through the range of contributions to the disciplinary knowledge base. Indeed it has been suggested that time-use methods are amongst the most established research techniques used to explore aspects of human occupation. However, the extent and nature of such activity in occupational therapy and occupational science has not been examined to date. Aim: This study sought to map the extent and nature of time-use research in occupational therapy and occupational science journals and the extent to which studies explored the relationship between time-use and health. Method: A scoping review method was used. Results: Sixty-one studies were included. Scandinavian countries contributed the largest number of studies (n = 16, 26%). While time-use diaries were used most frequently (n = 30, 49%) occupational therapists and occupational scientists have developed a range of data-collection instruments. Forty-nine studies (80%) focused on time-use in clinical or defined population sub-groups. Ten studies (16%) included an empirical examination of the relationship between time-use and health. Conclusion: Future research should examine time-use and health amongst well populations across the lifespan and in different parts of the world.     

Catheter balloon valvuloplasty of stenotic aortic valves. Part I: Anatomic basis and mechanisms of balloon dilation

Catheter balloon valvuloplasty of stenotic aortic valves has met with generally poor short- and long-term clinical results. Part of this problem resides with the lack of recognition of various etiologies of aortic stenosis. Part I of this review discusses the various etiologies of aortic stenosis and provides an anatomic basis for successful valve dilation. Results of an in vitro study indicate stenotic aortic valves are dilated by various mechanisms (cracking, stretching) based in part upon the etiology of the aortic valve stenosis.     

Circumferential quantitative analysis of planar 201T1 myocardial scintigraphy in the diagnosis of coronary artery disease

Methodology for the computer analysis of 201T1 myocardial perfusion images has been developed by several laboratories. Substantial evidence of the advantage of this approach over visual inspection alone has been reported. The currently available computer analyses use different algorithms to analyze 201T1 kinetics in the myocardium. The authors evaluated and compared two widely used software programs, Medical Data System (MDS): a mean-count profile, and the Cedars Sinai (CS): a maximal-count profile, of planar 201T1 scintigraphy for their ability to detect coronary artery disease (CAD).     

Jumping to delusions? Paranoia,probabilistic reasoning,and need for closure

Introduction. The present study was designed to replicate and extend the findings of Bentall and Swarbrick (2003). It was hypothesised that patients with a history of persecutory delusions would display higher need for closure and a more extreme jumping to conclusions bias than healthy control participants.

Methods. Twenty-two patients with a history of persecutory delusions and nineteen healthy control participants were administered a probabilistic reasoning task, along with self-report measures of depression and need for closure.

Results. The clinical group scored higher on need for closure than the controls, but showed no greater tendency to jump to conclusions. No relationship was found between need for closure and a jumping to conclusions bias.

Conclusions. The results confirm an association between persecutory delusions and need for closure, yet suggest that persecutory delusions in an outpatient sample can be seen in the absence of a jumping to conclusions bias.     

Gastric Emptying of Solid Meal in Male Chronic Alcoholics

Nausea and vomiting are common complaints in chronic alcoholics. Autonomic neuropathy and esophageal motor abnormalities are frequently observed in chronic alcoholics, but gastric emptying has not been studied in these patients. Gastric emptying of a solid meal was measured, using 99mTc-sulfur colloid cooked in a scrambled egg, in 10 male chronic alcoholics with upper gastrointestinal complaints of nausea and vomiting. All patients were adequately nourished, recently drinking, but just over withdrawal and free of clinical peripheral neuropathy. Gastric emptying in 10 alcoholics was similar to 5 normal controls (t 1/2 115 +/- 12 versus 107 +/- 8 min). These data suggest that upper gastrointestinal symptoms in chronic alcoholics are not related to gastric motor dysfunction.     

Accessory mitral valve leaflet causing aortic regurgitation and left ventricular outflow tract obstruction. Case report and review of published reports

Arrhythmias, aortic regurgitation, and symptoms of severe intermittent ventricular outflow obstruction developed in a 14 year old boy with a heart murmur who had been followed from infancy. These were caused by an accessory mitral leaflet, which was successfully removed at open heart operation. A review of 21 previously reported cases found a high incidence of associated cardiac malformations, appreciable subaortic obstruction in most patients, and a consistent attachment of the accessory tissue to the ventricular aspect of the anterior mitral leaflet. The characteristic echocardiographic appearance of a mobile mass arising from the area of aortic-mitral continuity is sufficient for the diagnosis of accessory mitral leaflet and echocardiographic examination will facilitate the surgical management of this condition.