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Biomedical subjects

R J Levine

Publications and source records attributed to R J Levine.

At least 19 recordsLinked to original sources
PubMed1992

Air-conditioned environments do not prevent deterioration of human semen quality during the summer.

OBJECTIVE: To determine if air conditioning might mitigate summer reductions in semen quality. DESIGN: Prospective study of semen quality in summer and winter. SETTING: Normal human volunteers were studied in the setting of a fertility laboratory. PATIENTS, PARTICIPANTS: Two groups of volunteers were selected from the vicinity of New Orleans: 64 men who worked indoors during the summer in air-conditioned environments and 76 others who worked outdoors. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Parameters of manual semen analysis were examined for seasonal and group differences. RESULTS: Remarkably similar reductions in semen quality during summer as compared with winter were observed in both indoor and outdoor workers, respectively, with regard to the following parameters of semen quality: 19% and 19% in sperm concentration, 25% and 27% in total sperm per ejaculate, 17% and 20% in motile sperm concentration, 13% and 15% in percent sperm with normal morphology, and 23% and 23% in concentration of morphologically normal motile sperm. CONCLUSIONS: These findings do not support the hypothesis that the heat of the summer is detrimental to male reproductive capacity. The available evidence suggests instead a possible role of photoperiod in causing the seasonal changes in semen quality.

Adolescent↗
PubMed1992

Situation ethics.

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Clinical Competence↗
PubMed1992

Mortality of iron foundry workers. II. Analysis by work area.

Plantwide analyses of the mortality experience of 8147 foundrymen revealed excesses for several diseases including lung cancer. Using indirect measures of smoking, it appeared that most, if not all, of the excess of lung cancer deaths could be explained by smoking habits. To explore further the possible association between these mortality excesses and foundry exposures, jobs were grouped into six work areas on the basis of similarities in production processes. The findings of analyses by work areas support the inferences from plantwide observations. No evidence was found of a relationship between lung cancer and foundry exposures. The pattern of mortality from emphysema and cerebrovascular disease in the different work areas paralleled that of lung cancer, suggesting that mortality from these diseases may have been influenced by a common etiologic agent, probably tobacco smoke. The data also reveal possible associations between metal pattern-making and colon cancer, silica or metal dust and stomach cancer, and carbon monoxide and ischemic heart disease.

Adult↗
PubMed1991

Deferred consent.

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Clinical Trials as Topic↗
PubMed1991

Medicalization of psychoactive substance use and the doctor-patient relationship.

Any attempt at medicalization of cocaine, heroin, marijuana, and other psychoactive substances of abuse in the United States is likely to encounter strong opposition by many responsible physicians. Such opposition would be grounded in their perception that medicalization would be contrary to the purposes of medical practice. Most physicians would, however, be willing to consider prescribing such substances for pathological users if such prescribing took place within the context of a fully developed doctor-patient relationship in which the patient recognized the dependency as undesirable and wanted to cooperate with the physician in a mutual effort to end the dependency or, if this were not feasible, to mitigate its destructive effects.

Behavior Control↗
PubMed1979

Antibody binding by native and denatured myosin and paramyosin.

By the techniques of immunodiffusion and fluorescent immunohistochemistry we show that antibodies to both the native and the SDS-denatured forms of the proteins, paramyosin and myosin, react with the native, SDS-denatured and glutaraldehyde-fixed forms of their respective antigens. Anti-denatured myosin also binds to both native and denatured forms of the proteolytic subfragments of myosin: globular subfragment-1 and alpha-helical LMM. Anti-native myosin, on the other hand, while able to bind to both native and denatured LMM or rod and to native and glutaraldehyde-fixed S-1, does not bind to SDS-denatured S-1.

Animals↗
PubMed1979

Some ethical considerations in clinical trials.

The ethical norms established in various codes and regulations are inadequate to resolve some of the ethical problems presented by clinical trials. They are stated too vaguely to provide unequivocal answers to many specific questions. In order to remedy this situation, many commentators have proposed the development of more specific and complex regulations. We propose that a more fruitful approach would be to examine the ethical principles underlying the norms and to apply these principles to the specific problems. We apply this approach to two questions: (1) Is it ethical to select subjects for a randomized clinical trial (RCT) exclusively from Veterans Administration (VA) hospitals? (2) In the conduct of a RCT is it necessary to disclose the fact that therapy will be determined by chance? We conclude that problems of justice arise not only because of the vulnerability of patients in VA hospitals but also because of the loss of the physician-patient relationship in an RCT. However, the use of patients in a VA hospital is not always unjust; in most cases such use can be made more just through various modifications in design. We also conclude that the fact of randomization should be disclosed in any situation in which it might materially affect the prospective subject's decision, and that the values and preferences of the subjects should be taken into account in determining what information might be material. This work is only a preliminary step toward analyzing ethical issues in clinical trials. While some would challenge our conclusions, we hope that our methods will facilitate clarity about the locus of disagreement in current controversies and about the value questions that must be answered in order to set an ethical context for the conduct of clinical trials.

Clinical Trials as Topic↗
PubMed1978

Cholera, non-vibrio cholera, and stomach acid.

Fasting and postprandial stomach acid production were low in 16 of 37 Bangalees convalescing from cholera or non-vibrio cholera. Gastric juice of hypochlorhydric patients did not kill cholera vibrios in vitro, whereas that from normochlorhydric patients rapidly killed vibrios in concentrations up to 10(10)/ml. To determine whether hypoacidity resulted from cholera or was a common predisposing factor, basal and betazole-hydrochloride-stimulated acid production were measured before and after cholera in a second group of patients consisting of American volunteers participating in a vaccine development programme. Cholera did not alter the stomach acid secretion of American volunteers, but low precholera basal acid production predispose to severe cholera. The results indicate that hypochlorhydria observed in convalescent Bangalee cholera patients is not caused by cholera, and must therefore have preceded it. Idiopathic tropical hypochlorhydria may be a major factor accounting for the high incidence of diarrhoea due to acid-sensitive pathogens in developing countries.

Achlorhydria↗
PubMed1978

How the industrial physician can reduce mortality from asbestos-related diseases.

Risk indicators for asbestos-related diseases (cancers of the lung, larynx, and alimentary tract; mesothelioma; and asbestosis) and methods of early detection are reviewed and evaluated. The best medical means of reducing mortality from these diseases is to recognize particularly susceptible persons during a preemployment examination and to recommend that they not be hired for jobs involving asbestos exposure. Workers necessarily exposed to asbestos should be enrolled in a medical screening program and urged not to smoke.

Asbestosis↗
PubMed1977

Epidemic faintness and syncope in a school marching band.

On Sept 21, 1973, during and following a football game at which they had participated, 57 members of an Alabama high school marching band (and one accompanying adult) experienced an illness characterized by headache, nausea, weakness, or dizziness. Six girls fainted. Thirty-six students were treated at a hospital emergency room. Those who had played wind instruments and had worn heavier uniforms including an impermeable plastic jacket overlay were affected earlier and more frequently than the others. Several organic causes were examined in an epidemiologic investigation and considered unlikely to explain the epidemic. Female preponderance, a bimodal epidemic curve, hyperventilation, relapses, and clinical features characterized by subjective complaints in the absence of physical findings suggested a syncopal reaction to heat exacerbated and propagated by mass hysteria.

Adolescent↗
PubMed1977

Changes in thick filament length in Limulus striated muscle.

Here we describe the change in thick filament length in striated muscle of Limulus, the horseshoe crab. Long thick filaments (4.0 microns) are isolated from living, unstimulated Limulus striated muscle while those isolated from either electrically or K+-stimulated fibers are significantly shorter (3.1 microns) (P less than 0.001). Filaments isolated from muscle glycerinated at long sarcomere lengths are long (4.4 microns) while those isolated from muscle glycerinated at short sarcomere lengths are short (2.9 microns) and the difference is significant (P less than 0.001). Thin filaments are 2.4 microns in length. The shortening of thick filaments is related to the wide range of sarcomere lengths exhibited by Limulus telson striated muscle.

Actin Cytoskeleton↗