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L Bernstein

Publications and source records attributed to L Bernstein.

At least 199 records · Page 11Linked to original sources

The role of hospice in reducing the impact of bereavement.

Survivors of patients in a randomized controlled trial of a hospital-based hospice were followed for 18 months after the patient's death. There were no significant differences in the anxiety or depression between hospice survivors (N = 56) and controls (N = 40). Neither were there significant differences in bed days, physician visits or scores on a 6-item health scale, even when the survivor's initial health status was held constant. No clear pattern of differences emerged in social participation, contacts with friends or relatives, smoking or drinking behaviors. We conclude that hospice care did not provide any protective effect for the bereavement period.

Alcohol Drinking↗

The epidemiology of pediatric acquired immunodeficiency syndrome.

HTLV III infection of children exhibits a relatively narrow spectrum in which the majority of patients develop clinical manifestations before the age of 2 years. In most instances the disease is transmitted in utero, whereby 35-65% of HTLV III-positive women give birth to an infected child. Discordant infection in twins is described. In fewer cases the disease is acquired through blood transfusions. In exceptional cases transmission via sexual abuse or use of needles may occur in young children. We have no evidence of intrafamilial horizontal disease transmission from child to child. The number of children with the disease may increase sharply. Around 2000 pregnancies in HTLV III-infected women are projected in New York City in the next year. Should all these pregnancies be completed, several hundred additional cases of pediatric AIDS may be expected in 1986.

Acquired Immunodeficiency Syndrome↗

Association between carcinogenic potency and tumor pathology in rodent carcinogenesis bioassays.

Carcinogenic potency (TD50) estimated from the results of 88 NCI/NTP carcinogenesis bioassays was examined by common target sites in rats and mice. Other indicators of a chemical's hazard were investigated, including whether tumors were induced at more than one site in a single sex-species group of test animals, whether tumors may have caused the death of the animal or were found at sacrifice, and whether metastases of induced tumors occurred. These hazard indicators are sometimes interrelated; however, the potency (TD50) values of chemicals which are hazardous by each of these measures spanned a wide range. Carcinogens which caused some type of fatal tumor were more likely than other carcinogens to cause tumors in multiple organ sites and multiple sex-species groups. Since these other hazard indicators were not related to carcinogenic potency, they should be included along with potency estimates such as the TD50 in summarizing the potential dangers of human exposures to a carcinogen and in comparisons of hazard among carcinogens.

Animals↗

An empirical comparison of methods used to estimate carcinogenic potency in long-term animal bioassays: lifetable vs summary incidence data.

Two methods for estimating carcinogenic potency from animal carcinogenesis bioassays (TD50-defined in the paper) are compared, one based on lifetable data and one based on summary incidence data. The lifetable analysis adjusts for the differential effects of toxicity among dose groups and for differences in the time pattern of tumor incidence, while summary incidence analysis does not. However, summary data are all that are usually available in the published results of animal cancer tests. Using NCI bioassay results which provide full lifetable data, we compare lifetable and summary estimates of potency and their statistical significance as well as the estimated shape of the dose-response curve. There is substantial agreement between these methods of analysis in terms of potency estimation, although lifetable estimates are usually more potent. But, there are some notable differences in the estimated shape of the dose-response curve, suggesting that both target site selection and method of analysis play an important role in risk estimation.

Actuarial Analysis↗

Month of birth of men with malignant germ cell tumours of the testis.

A recent paper has suggested that there is a temporal cycle in birth rates of men with testis cancer with a peak in April/May. We have investigated the suggestion using data from the South Thames and Los Angeles cancer registries. There is some slight evidence of a peak in August, which is confined to teratomas. The effects demonstrated are, however, too small and inconsistent to provide any real clue to the aetiology of testis cancer.

California↗

Chronological supplement to the Carcinogenic Potency Database: standardized results of animal bioassays published through December 1982.

This paper is a chronological supplement to our earlier publication, "A Carcinogenic Potency Database of the Standardized Results of Animal Bioassays." We report here results of carcinogenesis bioassays published in Technical Reports of the National Cancer Institute/National Toxicology Program between July 1980 and December 1982, and the general literature between July 1981 and December 1982. This supplement includes results of 280 long-term, chronic experiments of 114 test compounds, and reports the same information about each experiment in the same plot format as the earlier paper: e.g., the species and strain of test animal, the route and duration of compound administration, dose level and other aspects of experimental protocol, histopathology and tumor incidence, TD50 and its statistical significance, dose response, author's opinion about carcinogenicity, and literature reference. While a number of appendices are provided to facilitate use of this supplement, we have not duplicated here the material published earlier. Instead, we refer the reader to the earlier publications (Peto et al. and Gold et al.) for a thorough description of the numerical index of carcinogenic potency (TD50), a guide to the plot of the database, and a discussion of the sources of data, the rationale for the inclusion of particular experiments and particular target sites, and the conventions adopted in summarizing the literature. For 44 of the 114 chemicals reported in this second plot, results of earlier experiments are also given in the first plot; since only 1981-1982 results are reported here, the first plot is required for these repeated compounds. In this paper we also give corrections for errors that appeared in the earlier publication.

Animals↗

Serum testosterone levels in healthy young black and white men.

Blacks in the United States have the highest prostate cancer rate in the world and nearly twice that of whites in the United States. The 2:1 black-to-white ratio in prostate cancer rates is already apparent at age 45 years, the age at which the earliest prostate cancer cases occur. This finding suggests that the factor(s) responsible for the difference in rates occurs, or first occurs, early in life. Testosterone has been hypothesized to play a role in the etiology of prostate cancer, because testosterone and its metabolite, dihydrotestosterone, are the principal trophic hormones that regulate growth and function of epithelial prostate tissue. This report gives the results of assays of circulating steroid hormone levels in white and black college students in Los Angeles, CA. Mean testosterone levels in blacks were 19% higher than in whites, and free testosterone levels were 21% higher. Both these differences were statistically significant. Adjustment by analysis of covariance for time of sampling, age, weight, alcohol use, cigarette smoking, and use of prescription drugs somewhat reduced the differences. After these adjustments were made, blacks had a 15% higher testosterone level and a 13% higher free testosterone level. A 15% difference in circulating testosterone levels could readily explain a twofold difference in prostate cancer risk.

Adolescent↗

Increased frequency of adenocarcinoma of the uterine cervix in young women in Los Angeles County.

By hypothesizing that oral contraceptives (OC's) might have a carcinogenic effect on glandular cells of the cervix if given during periods of active metaplasia (e.g., postmenarchal adolescence), an increasing rate of cervical adenocarcinoma was predicted in young women who had been teenagers when OC's were introduced roughly 20 years ago. Secular trends for cervical carcinomas in non-Hispanic whites were examined by age, histologic type, and social class by using data from the Los Angeles County population-based tumor registry. Between 1972 and 1982, the frequency of invasive cervical adenocarcinoma in women under 35 years of age increased from about 2 to about 5 annually, amounting to an average rate of change of 8% per year (P less than .01). There was essentially no trend for women over 35 years old; the frequency of other invasive carcinomas (and of squamous carcinoma in situ) decreased at average rates of about 3% per year in women under 35 years of age and decreased more rapidly in older women. The increase in adenocarcinoma, unlike risk from cervical cancer generally, was most striking among young women residing in middle-to-upper income neighborhoods, who were the first to use OC's; in this subgroup the average rate of increase was 16% per year (P less than .05). These findings are compatible with our hypothesis and merit further study.

Adenocarcinoma↗

Higher maternal levels of free estradiol in first compared to second pregnancy: early gestational differences.

Serum samples drawn from 34 women in the early part of both their first and their second pregnancies were assayed for estradiol (E2), percentage of free E2, and sex hormone-binding globulin-binding capacity (SHBG-bc). Subjects were participants in the Collaborative Perinatal Study conducted by the National Institute of Neurological and Communicative Disorders and Stroke (Bethesda, MD) to evaluate factors related to adverse pregnancy outcome. All pregnancies were full term, and no offspring had a congenital malformation. After adjustment for week of pregnancy, the percentage of free E2 was 9% higher (two-sided P = .007) and the amount of free E2 was 17% higher (two-sided P = .03) in first-pregnancy sera. Total E2 was also 7% higher in first-pregnancy sera after adjustment for week of pregnancy; SHBG-bc was 7% lower after adjustment for week of pregnancy and 9% lower after simultaneous adjustment for week of pregnancy and weight at the start of pregnancy; but these differences were not statistically significant. These findings confirm our previously published hypothesis that the early part of a woman's first pregnancy differs endocrinologically from her second and may provide further insight into pregnancy-related risk factors for testis cancer and cryptorchidism and into the protection afforded by first full-term pregnancy against breast cancer.

Adult↗

Investigation of lung cancer among female cosmetologists.

Using a population-based cancer registry to identify subjects, a case-control study of female cosmetologists in Los Angeles County was conducted to investigate possible occupational and environmental causes for the elevated lung cancer risk found in this group. A standardized questionnaire was administered to proxy informants for decreased lung cancer patients and decreased nonpulmonary cancer control patients. No associations between lung cancer and specific beauty shop tasks, beauty product use, or environmental exposures were observed in the crude analysis or after controlling for smoking status. Case subjects had held more jobs outside of cosmetology than control subjects, but these jobs did not appear to be associated with any known hazardous exposures. Despite the elevated risk of lung cancer among female cosmetologists, researchers were unable to relate this excess to any specific occupational tasks or exposures. The excess of lung cancer in cosmetologists is most likely accounted for by a higher frequency of smoking in this occupational group.

Aged↗

Comparison of weight reduction with metoprolol in treatment of hypertension in young overweight patients.

Weight reduction was compared with metoprolol (200 mg daily) in a randomised placebo-controlled trial of first-line treatment of mild hypertension (diastolic blood pressure 90-109 mm Hg) in 56 overweight patients aged under 55 years. After 21 weeks of follow up the weight-reduction group had lost an average of 7.4 kg. The fall in their systolic pressure of 13 mm Hg was significantly greater than that in the placebo group (7 mm Hg) but not different from that in the metoprolol group (10 mm Hg). Their fall in diastolic pressure (10 mm Hg) was greater than that in both the metoprolol (6 mm Hg) and placebo (3 mm Hg) groups. At the end of the follow-up period 50% of patients in the weight-reduction group had a diastolic pressure of less than 90 mm Hg. In the metoprolol group there was a decrease in high density lipoprotein (HDL)-cholesterol and an increase in the ratio of total to HDL-cholesterol; in the weight-reduction group there was a decrease both in total cholesterol and in the ratio of total to HDL-cholesterol. Thus in this study population weight reduction produced significant and clinically important reductions in blood pressure but not the adverse effects on plasma lipids commonly associated with antihypertensive drug therapy.

Adult↗

Statistical errors invalidate conclusions in "Caffeine and unsaturated fat diet significantly promotes DMBA-induced breast cancer in rats".

The conclusion drawn in a recent paper by Minton and associates (Cancer 1983; 51:1249-1253), that caffeine and an unsaturated fat diet significantly promoted dimethylbenz(a)anthracene (DMBA)-induced breast cancer in rats, is based on fallacious statistical reasoning. Minton and associates based their conclusion on the mean latency to first tumor appearance for rats diagnosed with tumors. However, evaluation of percentages of tumor-bearing rats yields contrary results. Using data from a totally negative hypothetical two-group experiment, we demonstrate how such "conflicting" results could arise from differential intercurrent mortality in the two groups. The correct statistical analysis of this hypothetical experiment allows for differential intercurrent mortality and no conflict arises; the data of Minton and associates need to be analyzed by these methods.

9,10-Dimethyl-1,2-benzanthracene↗

Some tautologous aspects of the comparison of carcinogenic potency in rats and mice.

In risk estimation, the results of rodent carcinogenesis experiments are often used to quantitatively predict effects in man. The justification for this approach has in large part been dependent upon the good correlation of carcinogenic potency found between mice and rats over large numbers of test chemicals. Using the data base of chemicals tested by the NCI Bioassay Program, we observe that there is a very high correlation of the maximum doses tested (max-d) for rats and mice on a milligram per kilogram body weight per day basis. Next we show that the calculated carcinogenic potency (b-defined in the paper) is restricted to an approximately 30-fold range surrounding log(2)/max-d, which has a biological as well as a statistical basis. Since the max-d's for the set of NCI test chemicals vary over many orders of magnitude, it necessarily follows statistically that the carcinogenic potencies will be highly correlated. This "artifact" of potency estimation does not imply that there is no basis for extrapolating animal results to man. It does suggest, however, that the interpretation of correlation studies of carcinogenic potency needs much further thought.

Animals↗

A dental x-ray validation study. Comparison of information from patient interviews and dental charts.

Information was collected from dentists of a subset of participants in a case-control interview study conducted in Los Angeles County, California, in August 1980-August 1981 to evaluate the relationship of dental x-rays to tumors of the parotid gland. Complete dental charts were available from 142 dentists of 84 cases and from 130 dentists of 79 controls. Analysis of data from these interview-chart comparisons indicates that recall appears to be unbiased since the measures of agreement between interview and dental chart data are similar for cases and controls. The authors further conclude that interview data alone may be used for case-control comparisons of dental x-ray exposure and would, because of unbiased misclassification, tend to underestimate the relative risks.

Adult↗

Hospice role in alleviating the emotional stress of terminal patients and their families.

Terminally ill cancer patients in a Veterans Administration hospital were randomly assigned to receive hospice care. Follow-up evaluation through the time of death revealed no significant differences in anxiety or depression between hospice or control patients, but hospice patients exhibited significantly greater improvement in two of three measures of satisfaction (interpersonal care and involvement in care decisions). Hospice patients' significant others (SOs) showed some decrease in anxiety and greater satisfaction with involvement in care than did control SOs. The differences were attributable in part to hospice staff better meeting SOs' perceived needs.

Anxiety↗

Diet and drinking habits in relation to the development of alcoholic pancreatitis.

To determine whether increased intakes of fat and protein or particular drinking habits are associated with the development of alcoholic pancreatitis, a dietary study has been conducted. Patients with clinically evident alcoholic pancreatitis were compared with individuals with clinically evident alcoholic cirrhosis with respect to dietary and drinking habits before the onset of clinical illness. There was no significant difference between the two groups regarding intake of nutrients, drinking habits or type of alcoholic beverage consumed.

Adult↗