Characterization to species level of Mycobacterium avium complex strains from human immunodeficiency virus-positive and -negative patients

Forty human clinical Mycobacterium avium-M. intracellulare complex strains isolated in Greece were characterized to the species level by PCR with three sets of primers specific for one or both species. M. avium predominated in both human immunodeficiency virus-positive and -negative patients, but the frequency of M. intracellulare isolation appeared to be higher in the latter.     

Quantification of historical dust exposures in the diatomaceous earth industry

Quantitative estimates of dust exposure in a diatomaceous earth (DE) mining and milling operation have been derived based on air sampling records for the period 1948-1988. A total of 6395 records was included in the analysis. Conversion of results obtained by particle counting, expressed as millions of particles per cubic feet (mppcf) of gravimetrically from a filter cassette and expressed as mg m-3 total, were converted to mg m-3 respirable dust using a conversion factor derived from data obtained during the same periods at the plant. Conversion factors were calculated as the average difference of means on the log scale in order to provide stable and consistent conversions and as a ratio of arithmetic means so that the results could be compared with similar studies. After converting the available data to mg m-3 respirable dust, geometric mean (geometric standard deviation) concentrations were 0.37 (2.43) during the 1950s and 0.17 (2.35) during later periods. Exposures were estimated using two linear models, one estimating the changes in concentration over time, and the other providing job-specific mean exposures during the more recent period. Extrapolation of the estimates to periods prior to the availability of any data was done using a subjectively-determined scaling factor. The average estimated respirable dust concentrations for 135 jobs were 3.55 (+/-1.25), 1.37 (+/-0.48), 0.47 (+/-0.16) and 0.29 (+/-0.10) mg m-3 prior to 1949, 1949-1953, 1954-1973 and 1974-1988, respectively. Despite the limitations of the available data, the estimation procedures used are expected to provide reasonable quantitative estimates of silica-containing dust exposure for subsequent exposure-response analyses.     

Suicide risk assessment in a college student population.

A group of 211 students at a midwestern university completed the Suicidal Behaviors Questionnaire (M. M. Linehan & S. L. Nielsen, 1981), Adult Suicidal Ideation Questionnaire (W. M. Reynolds, 1991a), Multi-Attitude Suicide Tendency Scale (I. Orbach et al., 1991), Beck Helplessness Scale (A. T. Beck, A. Weissman, D. Lester, & L. Trexler, 1974), and the Reasons for Living Inventory (M. M. Linehan, L. J. Goodstein, S. L. Nielsen, & J. A. Chiles, 1983) to determine if this group of commonly used self-report measures can distinguish between individuals with high and low levels of suicidal ideation and history of self-harmful behaviors. Exploratory principal-axis factor analysis resulted in an interpretable 2-factor solution accounting for 36.2% of the variance in suicidality. Support for convergent validity of the chosen measures was also found. It appears that rapid, accurate assessment of university student suicide risk is possible. Implications for reduction of suicide risk in this segment of the population are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)