Amplification of the graft-versus-host reaction by partial body irradiation

An experimental model has been developed for the study of combined effects of partial body irradiation (PBI) and graft-versus-host disease (GVHD) in which irradiation is delivered to the thorax 24 hr prior to induction of GVHD in hybrid mice by the injection of parental lymphoid cells. In mice irradiated to 1000 cGy or exposed to low doses of allogeneic lymphoid cells (20 X 10(6)), survival was 100% at 250 days. In contrast, combination of the two treatments, GVHD and PBI, resulted in a mortality of 83% and a mean survival time of 29 days, indicating synergy between GVHD and PBI. From histological studies of the lung it appeared that about 40% of the deaths occurring after combined GVHD/PBR treatment might be attributable to pneumonia. The cause of death in the remaining mice receiving combined treatment is not known. Mice receiving combined PBI/lymphoid cell treatment develop a characteristic skin lesion that is not seen in nonirradiated mice and is confined to the irradiated area. The effect of preinduction PBR on the timing and severity of GVHD is similar to that which would be produced by an increase in the number of effector cells.     

An improved transilial crest bone biopsy drill for quantitative histomorphometry

Transilial crest bone biopsy with quantitative histomorphometry is an important technique for the assessment of metabolic and endocrine bone disease. The surface area of the histologic section suitable for histomorphometric analysis is reduced by the build-up of bone dust and by trabecular fracture, produced by the conventional Bordier bone drill. We describe here a modification of this drill that both allows escape of dust from around the cutting edge of the teeth and greatly reduces bone dust volume and trabecular fracture. In paired samples the new drill was shown to improve significantly the quality of the biopsy specimens.     

Effects of labeling and treatment of hypertension on perceived health

The effects of labeling a person as hypertensive have important implications for hypertension screening. The Hypertension Detection and Follow-up Program (HDFP) provides an opportunity to examine the effects of labeling, treatment, and study assignment on a large group of hypertensives (n = 10,070). Their answers to questions regarding perceived health and general well-being asked at baseline and again one year later were analyzed. There was no significant change in the perceived health status of persons who were unaware of their hypertension at baseline and remained untreated at one year (labeling alone). The effect of labeling plus treatment was associated with a significant decrease in perceived health. The effect of antihypertensive drug therapy on perceived health status was examined in persons who were aware of their hypertension but not on treatment at baseline, and on treatment at one year. The stepped care group (SC) had a significant improvement in their perceived health and a significant decrease in the amount of time spent worrying about their health. The referred care group (RC) had no change. Program assignment effects were studied in individuals aware of their hypertension and on treatment both at baseline and one year later. Both the SC and RC groups had a significant improvement in their perceptions of their health status. The SC group had a significant decrease in time spent worrying about their health, while the RC group showed no change. These reassuring results fail to support the suggestion that labeling persons as hypertensive is necessarily followed by negative psychological consequences.(ABSTRACT TRUNCATED AT 250 WORDS)     

Assessment of early alveolar particle clearance and macrophage function following an acute inhalation of sulfuric acid mist

Rabbits were exposed to submicrometer sulfuric acid mist at 1 mg/m3 for 1 hr to assess effects on alveolar region clearance of a polystyrene latex tracer aerosol. Bronchopulmonary lavage was performed at selected times after exposure for functional characterization of alveolar macrophages. In vivo, clearance was accelerated in acid exposed animals relative to sham controls. Acid exposure produced no change in the viability or numbers of macrophages recovered. Although an increase in the number of polymorphonuclear leukocytes, primary neutrophils, was observed by 1 hr in both acid and sham groups, compared to nonexposed controls, levels were normal by 12 hr in shams but continued elevated in the acid group through 24 hr. Reduced in vitro macrophage adherence was observed after acid exposure. In vivo uptake of the tracer particles by macrophages was enhanced during the first 3 hr after acid exposure and in vitro phagocytosis by polymorphonuclear leukocytes was increased through 48 hr post-exposure. The results indicate some functional alterations in free cells after in vivo exposure to H2SO4 and the production of a mild inflammatory response. This latter was associated with an acceleration of inert particle clearance from the alveolar region.     

Inhibitory effect of nifedipine on cholecystokinin-induced gallbladder contraction in man

A prospective study was performed on seven male and eight female patients with normal hepatobiliary findings to investigate the effect of 20 mg nifedipine on cholecystokinin-induced gallbladder contraction. Each patient received 1 IDU (Ivy dog unit) cholecystokinin per kg body weight intravenously on two consecutive days, with additional administration of 20 mg nifedipine sublingually on the second day. Gallbladder volumes were assessed by ultrasonography over a period of 25 minutes. Cholecystokinin induced a maximal reduction in the mean initial volume of 56.8 +/- 3.6%. After nifedipine, this volume change was significantly reduced to 30.9 +/- 5.1% (p less than 0.001). Thus our data suggest for the first time that the calcium-channel-blocking agent nifedipine can have an effect on human gallbladder kinetics.     

A review of the psychopharmacology of panic disorder: individual differences and non specific factors

This paper critically examines the pharmacological provocation and treatment of panic disorder. An analysis of research findings on how panic attacks are induced indicates that there are psychological and non specific factors that may mediate biochemical etiological models, and these individual differences need to be investigated further. This has important implications for the psychopharmacological management of panic. A review of studies on treating panic disorder with imipramine and alprazolam emphasizes the importance of several non specific factors that include the role of self-directed in vivo exposure and changes in dysphoria and self-efficacy (subjective beliefs regarding personal competency) in predicting outcome. It is recommended that any treatment of panic-related disorders include self-directed, in vivo exposure.