Effects of sulfur dioxide and formaldehyde on particle clearance in the rat

The effects of exposures to sulfur dioxide and formaldehyde atmospheres on the clearance of inhaled, insoluble tracer particles from the lungs of rats have been studied. The tracer particles employed were polystyrene latex microspheres radio-labeled with 51Cr. Following the deposition of the 1.9-micron activity median aerodynamic diameter (AMAD) particles, the rats were divided into 3 groups for a single 4-h exposure to purified air, 20 ppm sulfur dioxide, or 20 ppm formaldehyde. Early, presumably upper-respiratory-tract, clearance was monitored by analysis of radioactivity excreted in feces, while late, presumably deep-lung, clearance was followed by thoracic counting of the animals. Both the sulfur dioxide and formaldehyde atmospheres did significantly delay early clearance (p less than 0.1, two-tailed t-test). However, the late clearance rates of the two pollutant-exposed groups of rats were not significantly different from that of the purified air-exposed group of rats. Although sulfur dioxide had numerically greater effects than formaldehyde, the differences were not statistically significant at the p less than 0.1 level.     

Sex and the cystectomized male: A lack of communication,a need for education

When cancer of the bladder is treated by removal of the malignant organ, there is a high incidence of impotency in males. A retrospective study of 71 adult patients revealed misconceptions, misinformation, and misinterpretation that could have been alleviated by more timely and appropriate counsel. Nurse-enterostomal therapists are identified as potentially valuable sex counselors but their training in this field is limited. A need for patient education is demonstrated and a plea for follow-up attention to sexual concerns in the extended postoperative period is issued.     

Airways Hyperresponsiveness in High School Athletes

Adult athletes have a higher prevalence (11%-50%) of exercise-induced bronchoconstriction (EIB) and airways hyperresponsiveness (AHR) than the population at large (7%-11%): reports describing EIB/AHR in adolescent athletes are scant. Hypotheses: 1) a minimum AHR prevalence of 20% would be revealed in a group of high school athletes; 2) demographic data would predict AHR; 3) AHR-positive athletes would preferentially choose low ventilation sports. Eucapnic voluntary hyperpnea (EVH) was used to test for AHR in 23% of all athletes (79 of 343) of a midwestern high school. The AHR was defined by at least a 10%, 20%, or 25% decline in FEV₁, FEF_25-75, or PEFR at 1, 5, 10, or 15-min post-EVH, respectively. Results: 30 of 79 (38%) tested positive for AHR; demographic data tended to predict AHR, as correlations between the total number of years exercised with the greatest decline in FEV₁ and the total number of days exercised with the greatest decline in FEV₁ following the EVH challenge tended to be significant (r = 0.354; p = 0.055 and r = 0.314; p = 0.091, respectively); and 69% of AHR-positive students played only low ventilation sports. Conclusion: AHR prevalence was 38% in athletes of a midwestern high school; demographic data tended to predict AHR; those with AHR preferentially play low ventilation sports.     

Naratriptan as short-term prophylaxis of menstrually associated migraine: a randomized, double-blind, placebo-controlled study

OBJECTIVE: To determine the efficacy of naratriptan 1-mg and 2.5-mg tablets twice daily compared with placebo as short-term prophylaxis of menstrually associated migraine. BACKGROUND: Approximately 60% of women with migraine report headaches associated with their menstrual cycles. Results from an open-label study suggest that short-term administration of sumatriptan is useful in the prophylaxis of menstrually associated migraine. METHODS: A randomized, double-blind, three-arm, parallel-group, placebo-controlled study was conducted in women aged 18 years or older with a history of migraine with or without aura, as defined by the International Headache Society, of at least 6 months. Two dose strengths of naratriptan (1 mg, 2.5 mg) or identical-appearing placebo tablets (1:1:1) were administered twice daily for 5 days starting 2 days prior to the expected onset of menses across four perimenstrual periods. End points included the number of menstrually associated migraines, total migraine days, peak headache severity, lost work/activity time, migraine-related quality of life, and incidence of adverse events. RESULTS: Overall, the intent-to-treat population comprised 206 women (naratriptan 1 mg, n = 70; naratriptan 2.5 mg, n = 70, and placebo, n = 66); 171 women treated four perimenstrual periods. Significantly more perimenstrual periods per subject treated with naratriptan, 1 mg, were headache-free compared with placebo (50% versus 25%, P =.003). Naratriptan, 1 mg, significantly reduced the number of menstrually associated migraines (2.0 versus 4.0, P <.05) and menstrually associated migraine days (4.2 versus 7.0, P <.01) compared with placebo. More patients treated with naratriptan, 1 mg, were headache-free across all treated perimenstrual periods compared with placebo (23% versus 8%). No difference in headache severity was observed in breakthrough headaches. The incidence and severity of adverse events was similar across treatment groups. Naratriptan, 2.5 mg, was not statistically superior to placebo for any measure. CONCLUSIONS: Naratriptan, 1 mg, with tolerability similar to placebo, is an effective, short-term, prophylactic treatment for menstrually associated migraine.     

Effect of positive and negative pressure breathing on sodium and water excretion

Positive and negative pressure breathing purportedly alter renal sodium and water excretion by modifying hemodynamics and/or hormonal regulators of sodium and water homeostasis. To test this hypothesis we monitored hemodynamic and hormonal responses in seven normal men to (1) continuous positive pressure breathing (19 +/- 1 mm Hg for 30 minutes) after water loading (urine volume = 15 +/- 1 ml/min); and (2) continuous negative pressure breathing (11 +/- 1 mm Hg for 30 minutes) after maintenance water ingestion (urine volume = 4 +/- 1 ml/min), in random order. Each study was repeated on a control day without pressure breathing. Results were as follows (mean +/- SE, p less than 0.05): (1) continuous positive pressure breathing decreased urinary sodium from 0.28 +/- 0.07 to 0.17 +/- 0.04 mEq/min, increased atrial natriuretic peptide from 34.2 +/- 4.9 to 48.5 +/- 6.9 pg/ml, and had no effect on osmolar and free water clearances, cardiac output, plasma renin activity, or plasma aldosterone and plasma arginine vasopressin levels; and (2) continuous negative pressure breathing increased free water clearance from 0.6 +/- 0.7 to 4.5 +/- 1.2 ml/min, urine volume from 4.0 +/- 0.8 to 8.9 +/- 1.3 ml/min, and cardiac output from 5.1 +/- 0.4 to 7.0 +/- 0.6 L/min in a proportional manner (r = 0.40, p less than 0.01) and had no effect on osmolar clearance, urinary volumes of sodium and potassium, plasma renin activity, plasma aldosterone, atrial natriuretic peptide, and arginine vasopressin.(ABSTRACT TRUNCATED AT 250 WORDS)     

Reactivation of latent herpes simplex virus infection by ultraviolet light: a human model

Infection with herpes simplex virus often results in a latent infection of local sensory ganglia and a disease characterized by periodic viral reactivation and mucocutaneous lesions. The factors that trigger reactivation in humans are still poorly defined. In our study, five patients with documented histories of recurrent herpes simplex virus infection on the buttocks or sacrum were exposed to three times their minimal erythema dose of ultraviolet light. Site-specific cutaneous herpes simplex virus infection occurred at 4.4 +/- 0.4 days after exposure to ultraviolet light in 8 of 13 attempts at reactivation. We conclude that ultraviolet light can reactivate herpes simplex virus under experimentally defined conditions. This model in humans should prove useful in evaluating the pathophysiology and prevention of viral reactivation.     

Development and validation of the Child-to-Mother Violence Scale

This article describes the development and tests the reliability and validity of a new survey instrument, the Child-to-Mother Violence Scale (CMVS). This instrument was devised specifically to measure data regarding the incidence, perpetrators, targets, experiences and influences on child-to-mother violence as the first phase of a larger study that investigated child-to-mother violence in the western suburbs of Sydney, Australia.     

Effectiveness of brief training in cognitive behaviour therapy techniques for palliative care practitioners

We describe training in CBT techniques for 20 palliative care practitioners delivered as 12 days' equivalent teaching plus skills-building supervision over a six month period. Audiotapes of trainees' interactions with patients during their usual work were rated using a specially devised 'Cognitive First Aid' rating scale (CFARS). The CFARS was highly internally consistent (Cronbach's Alpha 0.93) and inter-rater reliability was high. Trainees showed significant gain in CBT skills competency over six months (p=0.001). After initial training, half the trainees were randomised to discontinue supervision; their measured CBT skill dropped as did their self-reported confidence when reassessed six months later, whereas those who continued in supervision gained further skill and maintained confidence (p=0.007). Palliative care practitioners can be trained in CBT skills by a simple and brief training course and supportive, skills-building supervision. These skills are compatible with national guidelines on delivery of psychological support to patients at all stages of cancer. Supervision is necessary to ensure maintenance of skills and confidence to use them.