Immunological and respiratory reactions in workers exposed to organic dusts

The relationship of skin reactivity and serum immunoglobulin E (IgE) levels to the prevalence of chronic respiratory symptoms and to ventilatory capacity is examined in workers exposed to different organic aerosols. The results from group of control workers similarly tested are also presented. Workers exposed to occupational allergens had positive skin tests more frequently than did controls, except for soy bean workers. Workers with positive skin tests to occupational allergens had a higher prevalence of almost all symptoms than those with negative skin tests although the differences did not always reach statistical significance. Workers with positive skin reactions in general had significantly higher serum IgE levels than did workers with negative skin reactions. There were across-shift reductions of ventilatory capacity in all groups of exposed workers, varying for forced vital capacity from 1.7% to 13.3%, for forced expiratory volume from 0.4%–21.9%, for maximum flow rates at 50% from 1.5% to 16.1% and for maximum flow rates at the last 25% of control vital capacity from 0% to 24.9%. There was, however, no correlation between acute and chronic lung function changes and skin reactivity or IgE values. Our data suggest that although exposure to organic aerosols may be associated with frequent immunologic reactions, these findings do not predict objective respiratory impairment.The research was supported in part by grant no. JBP 733 from the National Institutes of Health, Bethesda, Md., USA, and by grant no. RO1 OHO-2593-04 from the National Institutes of Occupational Safety and Health, Centers for Disease Control, Atlanta, Ga., USA     

Mutations Affecting the Rossman Fold of Isoleucyl-tRNA Synthetase Are Correlated with Low-Level Mupirocin Resistance in Staphylococcus aureus

The isoleucyl-tRNA synthetase (ileS) gene was sequenced in toto from 9 and in part from 31 Staphylococcus aureus strains with various degrees of susceptibility to mupirocin. All strains for which the mupirocin MIC was greater than 8 microg/ml contained point mutations affecting the Rossman fold via Val-to-Phe changes at either residue 588 (V588F) or residue 631 (V631F). The importance of the V588F mutation was confirmed by an allele-specific PCR survey of 32 additional strains. Additional mutations of uncertain significance were found in residues clustered on the surface of the IleS protein.     

Role of nitric oxide in relaxation of the longitudinal layer of rectal smooth muscle

PURPOSE: This study was designed to investigate the role of nitric oxide in neurogenic relaxation of the longitudinal layer of human rectal smooth muscle. METHODS: Tissue was obtained from the mid rectum of patients undergoing anterior resection for carcinoma. Adjacent strips of longitudinal muscle were dissected and mounted in organ baths for isometric tension recording. In preliminary experiments to determine the response of strips to cholinergic, adrenergic, and potential excitatory agonists, strips were superfused with standard Krebs solution (37±0.5°C; pH, 7.4±0.05). Investigation of inhibitory, nonadrenergic noncholinergic responses required the addition of 3×10⁻⁶ M histamine to induce reproducible and stable tension for five-minute “test” periods, during which electrical field stimulation (EFS) and additional drugs were applied. In these experiments, strips were superfused with Krebs solution that contained atropine sulfate (3×10⁻⁶ M) and guanethidine (3×10⁻⁶ M). RESULTS: The response to cholinergic and adrenergic agonists was typical of nonsphincter specialized gastrointestinal smooth muscle. EFS elicited frequency-dependent, neurogenic (tetrodotoxin-sensitive) relaxations of precontracted strips, which were reduced in dose-dependent fashion by addition ofNω-nitro-l-arginine and restored by addition of 3×10 ⁻⁴ M l-arginine but not by d-arginine. Addition of exogenous nitric oxide (sodium nitroprusside) mimicked the relaxant response induced by EFS. CONCLUSION: Smooth muscle from the longitudinal layer of human rectum receives an intrinsic inhibitory innervation mediated by nitric oxide. Supported and financed by the Medical Research Council, United Kingdom. John Stebbing is in receipt of a Medical Research Council Clinical Training Fellowship. Read at the meeting of The American Society of Colon and Rectal Surgeons, Seattle, Washington, June 9 to 14, 1996.     

Effective epilation of white and blond hair using combined radiofrequency and optical energy.

OBJECTIVE: The present study examined the long-term photoepilatory effect on blond and white hair of a combined intense pulsed light (680-980 nm) device with a bipolar radiofrequency component producing electrical current at a depth of 4 mm. MATERIALS AND METHODS: Thirty-six adult women with white and blond hair (skin phenotypes I-V) were included in the study. The chin and upper lip were treated with four treatment sessions over 9-12 months with long-term follow-up performed at month 18 (6 months after the last treatment). The level of RF energy was 20 J/cm3, while optical fluences varied from 24 to 30 J/cm2. Hair counts and photographic evaluation of some sites were obtained at baseline, months 1, 3 and 5 and the final treatment session. RESULTS: An average hair removal of 48% was observed at month 18 (6 months following the final treatment session). A slightly higher photoepilatory efficiency was noted for blond hair (52%) versus white hair (44%) treatment sites. CONCLUSION: Combined radiofrequency and optical energy technology may produce effective photoepilation of blond and white hair phenotypes.     

Effect on fetal mouse development of exposure to MR imaging and gadopentetate dimeglumine

Pregnant mice were exposed to one of five regimens at 9.5 days of gestation: no treatment (group 1), intraperitoneal injection of normal saline (group 2), intraperitoneal injection of gadopentetate dimeglumine (group 3), intraperitoneal injection of gadopentetate dimeglumine and magnetic resonance (MR) exposure (group 4), and MR exposure alone (group 5). At 18 days of gestation, the mice were sacrifice and fetuses were removed and examined for the following end points: litter size, number alive or dead, fetal weight, extremity morphology, eye and ear development, and appearance of the head. A total of 739 fetuses were analyzed: group 1 (n = 161), group 2 (n = 149), group 3 (n = 142), group 4 (n = 136), and group 5 (n = 151). The only statistically significant difference was a lower mean fetal weight in the saline-injection group compared with the control group. The results show that MR exposure with and without gadopentetate dimeglumine had no adverse effect on the end points analyzed.     

A group intervention to reduce smoking in individuals with psychiatric disorder: brief report of a pilot study

Objectives: To evaluate a group intervention to help individuals with psychiatric disorder stop smoking.
Method: A waitlist-treatment crossover design. Outcome measures included smoking cessation, motivation to stop, the Fagerstrom Test for Nicotine Dependence (FTND), urinary cotinine and psychiatric symptoms on the General Health Questionnaire.
Results: 38 subjects participated, of whom 19 completed the waitlist and intervention phases. There were no significant differences between subjects and dropouts. During the waitlist period there were no significant changes in tobacco use. At the end of the intervention, almost a quarter had stopped smoking, ( z = -2.24, p =0.02). Subjects also showed significant improvements on state of change, FTND score and urinary cotinine levels. These improvements were maintained at three-month follow-up (n=10). Psychiatric morbidity showed no change.
Conclusions: It is possible to reduce smoking in individuals with psychiatric disorder.
Implications: Larger randomised controlled trials are indicated to determine the relative contributions of nicotine replacement, bupropion and group interventions to smoking cessation in this population.