Biomedical subjects
Publications and source records attributed to M Markowitz.
The current status of rheumatic fever is reviewed and the reasons for its decline in the United States are explored. Continuation of primary prevention efforts is recommended or there could be a resurgence of this disease. The need for further research continues because rheumatic fever is still a major health problem for much of the world's population.
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The relationship between the perceived characteristics of a job and employee alcoholism was examined. Research has determined that it is a perceived lack of power that better distinguishes an alcoholic from a nonalcoholic, and that such a perceived lack of power causes an alcoholic to suffer frustration because of the inability to feel competent and self-determining. The job has been shown to influence psychological functioning in all aspects of an individual's life, and specific job characteristics which contribute to feelings of competence and self-determination were studied. These included (1) personal power in the organizational hierarchy, (2) participation in decision making, (3) job autonomy and (4) job responsibility. Regression analysis of data from questionnaires administered to 293 full-time employees demonstrated significant F ratios for perceived job responsibility and perceived lack of personal power in the organization when regressed against the CAGE questionnaire, which identified covert alcoholics. These data support the notion that aspects of the job are associated with and may help to induce alcoholism among employees.
We investigated possible abnormalities of central-nervous-system regulation of luteinizing hormone secretion in the polycystic-ovary syndrome by determining the plasma concentrations of luteinizing hormone over a 24-hour period in five teenage girls with the syndrome; profiles of prolactin and cortisol were also obtained. Four of the five patients had strikingly abnormal plasma luteinizing hormone profiles: whereas normal pubertal girls have a daily surge in secretion of luteinizing hormone that is coterminous with their nocturnal sleep period, our patients had surges that were grossly desynchronized from their sleep period, occurring seven to eight hours later in the daytime than normal. The chronobiologic disturbance involved only luteinizing hormone; the profiles of cortisol and prolactin were normal. This finding points to the central nervous system as the probable locus of the initiating pathophysiology of polycystic-ovary syndrome.
Peripheral resting mononuclear leukocytes were compared for their capacities to repair DNA lesions induced by a 1-hour exposure to a standardized 10-microM dose of N-acetoxy-N-2-fluorenylacetamide (N-AcO-2-FAA). Leukocytes from the following 3 groups were studied: 39 control subjects, 40 patients after colonic resection because of colorectal cancer (disease-free at the time of this study), and 28 individuals with a hereditary predisposition to colorectal cancer. Although the level of N-AcO-2-FAA that bound to mononuclear leukocyte DNA was the same for the various population groups, the level of N-AcO-2-FAA-induced unscheduled DNA synthesis (UDS) was significantly reduced in the mononuclear leukocytes of individuals who had had colorectal cancer or a genetic predisposition for the disease. These findings indicate that a deficiency in mononuclear leukocyte DNA repair synthesis is associated with the development of colorectal cancer in these populations. Our observation of this nonspecific UDS deficiency (relating to colorectal cancer) was not explained by experimental variations among the sampled groups with regard to individual differences in lymphocyte heterogeneity, age, sex, smoking habits, or blood pressure.
Conventional screening tests (blood lead and erythrocyte protoporphyrin levels) may not accurately reflect the magnitude of lead storage in children with mild to moderate increases in lead absorption, as assessed by edetate disodium calcium testing. Children with blood lead levels higher than 30 micrograms/dL and erythrocyte protoporphyrin levels higher than 50 micrograms/dL warrant careful measurement of the size of chelatable, potentially toxic lead stores. Edetate disodium calcium testing provides a more precise basis for therapeutic decisions in a child with mild to moderate increases in lead absorption.
Circadian rhythms of ionized calcium and phosphate concentrations have been demonstrated in human blood. A computer-derived model curve representing the 24-hour fluctuations in ionized calcium cannot be correlated consistently with curves for total calcium or phosphate. Knowledge of these circadian rhythms provides a physiological basis for further understanding the interactions between blood minerals and calcium-regulating hormones.
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Rheumatic fever is no longer a significant health problem in socioeconomically advanced countries, but it still causes 25% to 40% of all cardiovascular disease in the rest of the world, including tropical countries where it was once believed to be rare. Differences in clinical manifestations may have obscured the rheumatic fever syndrome in the past, but there is reason to believe that the incidence of the disease has increased with urbanization. In any event, carditis is severe and frequently leads to advanced heart disease. Rheumatic fever is, to a large extent, preventable. Obstacles to effective prevention programs are discussed.
Many new antibiotics and countless formulations of old ones have been introduced during the past three decades. None has supplanted BPG. It remains the only drug that can provide antibiotic blood levels for several weeks following a single intramuscular injection. This property makes BPG the ideal preparation for treponematoses and group A streptococcal infections in patients who are not allergic to penicillin and for whom single-session therapy is desirable or necessary. Sensitivity reactions from BPG are less frequent and less severe than those from aqueous or procaine penicillin G. In certain situations, such as the prevention of rheumatic fever and rheumatic heart disease, the fear of a reaction in a patient with a negative past history of penicillin allergy is no justification for withholding BPG when it is clearly the drug of choice.
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Rheumatic fever has decreased in frequency and severity, but the disease has not been eradicated in this country, especially in low socioeconomic populations. Carditis is less common, and changes in the frequency of other rheumatic manifestations such as chorea has made the clinical diagnosis more difficult. Streptococcal antibody tests are still the most useful laboratory aid, but care must be taken against overinterpretation. The search for the answer to the pathogenesis puzzle continues. Until the nature of the disease is better understood, it is unlikely that rheumatic fever will be eradicated. In the meantime, however, the incidence of the disease can be reduced further by improved medical care for deprived populations.
Two cases of bilateral Wilms' tumor are presented with discussion of angiographic features. Emphasis is placed on selective angiography in addition to inferior vena cavography for complete evaluation. Because of the incidence of bilateral disease, and the highly vascular nature of the tumor, selective angiography of the contralateral side should be considered in the initial evaluation of unilateral Wilms'tumor. Evaluation of the interface between tumor and normal parenchyma is extremely important in bilateral disease, in anticipation of partial nephrectomy.
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Explore the source record for details and available documents.
Explore the source record for details and available documents.