The pulmonary effects of ozone and nitrogen dioxide alone and combined in healthy and asthmatic adolescent subjects

Separate exposures to 0.12 ppm ozone (O3) or 0.18 ppm nitrogen dioxide (NO2) have not demonstrated consistent changes in pulmonary function in adolescent subjects. However, in polluted urban air, O3 and NO2 occur in combination. Therefore, this project was designed to investigate the pulmonary effects of combined O3 and NO2 exposures during intermittent exercise in adolescent subjects. Twelve healthy and twelve well-characterized asthmatic adolescent subjects were exposed randomly to clean air or 0.12 ppm O3 and 0.30 ppm NO2 alone or in combination during 60 minutes of intermittent moderate exercise (32.5 1/min). The inhalation exposures were carried out while the subjects breathed on a rubber mouthpiece with nose clips in place. The following pulmonary functional values were measured before and after exposure: peak flow, total respiratory resistance, maximal flow at 50 and 75 percent of expired vital capacity, forced expiratory volume in one second and forced vital capacity (FVC). Statistical significance of pulmonary function changes was tested by analysis of covariance for repeated measures. After exposure to 0.12 ppm O3 a significant decrease was seen in maximal flow at 50% of FVC in asthmatic subjects. After exposure to 0.30 ppm NO2 a significant decrease was seen in FVC also in the asthmatic subjects. One possible explanation for these changes is the multiple comparison effect. No significant changes in any parameters were seen in the asthmatic subjects after the combined O3-NO2 exposure or in the healthy subjects after any of the exposures.     

Valproic acid induced encephalopathy--19 new cases in Germany from 1994 to 2003--a side effect associated to VPA-therapy not only in young children.

Valproic acid (VPA) is a broad-spectrum antiepileptic drug and is usually well-tolerated. Rare serious complications may occur in some patients, including haemorrhagic pancreatitis, bone marrow suppression, VPA-induced hepatotoxicity and VPA-induced encephalopathy. The typical signs of VPA-induced encephalopathy are impaired consciousness, sometimes marked EEG background slowing, increased seizure frequency, with or without hyperammonemia. There is still no proof of causative effect of VPA in patients with encephalopathy, but only of an association with an assumed causal relation. We report 19 patients with VPA-associated encephalopathy in Germany from the years 1994 to 2003, none of whom had been published previously.     

Postantibiotic effect of clarithromycin alone and combined with ethambutol against Mycobacterium avium complex.

The postantibiotic effect (PAE) of clarithromycin alone and in combination with ethambutol was determined for two clinical blood isolates of Mycobacterium avium complex. An average PAE, ranging from 5.5 to 18.0 h, was noted for each isolate at each clarithromycin concentration except when isolate B was exposed to clarithromycin at the MIC. The addition of ethambutol did not enhance the PAE observed with clarithromycin alone. The clinical implications of the PAE of clarithromycin for M. avium complex remain to be determined.     

Comparison of medical school performances and career plans of students with broad and with science-focused premedical preparation.

This paper reports (1) a method for classifying students according to the breadth of their premedical preparation and (2) a comparison of the medical school performances and career plans of the students thus classified. The method was developed in 1987, in part by using input from a small but representative sample of admission officers. Students were grouped according to undergraduate major, ratio of nonscience-to-science course hours, and extracurricular involvement. After tentatively classifying all individuals who had entered U.S. medical schools in 1981 as having either broad or science-focused preparation, the author compared the two most distinct groups selected from a random sample of the individuals in each classification: 59 individuals constituted the final broadly prepared group, and 73, the science-focused group. The science-focused group attained higher mean scores (p less than .05) on three science sections of the National Board of Medical Examiners (NBME) Part I examination, and the broadly prepared group scored higher on the Behavioral Sciences section (p less than .05). No other significant difference was evident between the groups' mean scores on the NBME Parts I, II, or III, or in the groups' rates of experiences of academic difficulty, specialty choice distributions, or percentages of individuals deciding to pursue research careers. The author concludes that this method of classifying students is useful and that the students with less premedical focus in the sciences were able to perform well.     

Self-rated depressive symptoms in medical inpatients: age and racial differences.

One thousand and eleven men under age forty (n = 161) or over age sixty-four (n = 850) admitted to medical and neurological services of an acute care hospital were screened for depressive symptoms as part of the Durham VA Mental Health Survey. Thirty-three percent of younger and 22 percent of older men scored 11 or higher on the Geriatric Depression Scale. Self-rated symptoms were most prevalent among younger whites (40%) and least common in older blacks (19%). Other exogenous factors such as being retired or unemployment and prior psychiatric history were also related to depressive symptoms, as were poor functional status, impaired cognitive status, and respiratory illness. Coping resources associated with fewer symptoms were social support and moderate alcohol use. In a subgroup of 443 patients, self-rated symptoms were compared with observer-rated symptoms. Agreement was highest among young Whites and lowest in older Blacks. Other correlates also varied depending on whether self-rated or observer-rated symptoms were considered. We conclude that self-rated symptoms are common among medical inpatients, are linked with and confounded by certain health and sociodemographic factors, and may be relatively insensitive as a measure of depression in elderly blacks.