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J S Mandel

Publications and source records attributed to J S Mandel.

At least 73 records · Page 4Linked to original sources
PubMed1995

Collaborative AIDS prevention research in the developing world: the CAPS experience.

BACKGROUND: Prevention through behavior change is the only way to control the spread of HIV infection in the developing world. Success in prevention requires consistent and persistent intervention over time, a clear understanding of the realities of target populations and involvement of members of these populations in prevention efforts. Applied local research is urgently needed, especially in the developing world, to design interventions that meet these criteria and to test their effectiveness. CENTER FOR AIDS PREVENTION STUDIES (CAPS) MODEL OF INTERNATIONAL COLLABORATIVE RESEARCH: Each year, eight to 10 scientists from developing countries visit CAPS in San Francisco for 10 weeks of intensive learning and collaboration. The main emphasis is on designing a protocol for a research project related to AIDS prevention in the visiting scientist's home country. CAPS provides pilot study funding and technical assistance to implement the project. RESULTS: The quality of the resulting collaborative research is represented by the articles published in this volume and by the many alumni of the program who have undertaken additional research projects and/or assumed leadership positions in AIDS control efforts in their countries.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Impact of an intervention on HIV, sexually transmitted diseases, and condom use among sex workers in Bombay, India.

OBJECTIVE: To develop and test an HIV intervention targeting sex workers and madams in the brothels of Bombay. SUBJECTS AND METHODS: In a controlled intervention trial, with measurements before and after the intervention, 334 sex workers and 20 madams were recruited from an intervention site, and 207 and 17, respectively, from a similar control site, both in red-light areas of Bombay. All sex workers were tested for antibodies to HIV and syphilis, and for hepatitis B surface antigen. Information on sexual practices, condom use and knowledge of HIV was collected by interviewer-administered questionnaire. All subjects in the intervention group underwent a 6-month program of educational videos, small group discussions and pictorial educational materials; free condoms were also distributed. The blood tests and the questionnaire were readministered to all subjects at both sites immediately after the intervention. Both groups were followed for approximately 1 year. RESULTS: The baseline level of knowledge about HIV and experience with condoms was extremely low among both sex workers and madams. The baseline prevalence of HIV antibodies was 47% in the intervention group and 41% in the control group (P = 0.17). The incidence densities for HIV and sexually transmitted diseases were significantly different in the two groups (all P < 0.005): 0.05 and 0.16 per person-year of follow-up for HIV, 0.08 and 0.22 per person-year for antibodies to syphilis, and 0.04 and 0.12 per person-year for hepatitis B surface antigen in the intervention and control women, respectively. Following the intervention, women reported increased levels of condom use, and some (41%) said they were willing to refuse clients who wouldn't use them. However, both the sex workers and the madams were concerned about losing business if condom use was insisted upon. CONCLUSIONS: Both HIV prevalence and incidence are alarmingly high among female sex workers in Bombay. Successful interventions can be developed for these women, and even a partial increase in condom use may decrease the transmission of HIV and sexually transmitted diseases. Intervention programs of longer duration that target madams and clients and make condoms easily available are urgently needed at multiple sites in red-light areas.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Adolescent sexuality in Saint Petersburg, Russia.

OBJECTIVES: To describe adolescent knowledge, attitudes and behavior relevant to sexuality and the prevention of AIDS in Saint Petersburg, Russia. SUBJECTS AND METHODS: A cross-sectional descriptive study was designed, taking a random sample of 10th grade students at 14 Saint Petersburg grade schools, which were stratified by socio-economic district. A total of 185 female and 185 male students completed a self-administered 46-item questionnaire, with a response rate of 94%. RESULTS: From the questionnaires, 20% of females and 31% of males reported having had sexual intercourse and 25% of females and 12% of males reported being sexually abused. These adolescents displayed much misinformation about sexual matters and AIDS prevention. Only 25% of the females and 34% of the males believed that condoms should be used just once, and 38% of each sex believed that if washed, they could be used multiple times. Many respondents, especially males, rated their knowledge about sexual matters as high or adequate. Support for sex education was strong, especially among females, and respondents generally saw sex education as improving sexual pleasure. Most information sources about sexual activity were either not considered very credible, or not adequately accessible. CONCLUSIONS: Substantial reported rates of sexual abuse, sexual experience and much misinformation and unwarranted attitudes toward condoms, safer sexual practices and HIV/AIDS suggest the need for vigorous sex education programs for Russian youth. The early and sustained education of girls is especially important. Sex education should be introduced at an early age so that children can be taught how to reduce the risks of sexual abuse, HIV infection and other sexually transmitted diseases, and to improve their sexual experiences as responsible adults.

Acquired Immunodeficiency Syndrome↗
PubMed1995

'Superstar' and 'model brothel': developing and evaluating a condom promotion program for sex establishments in Chiang Mai, Thailand.

OBJECTIVES: We developed and evaluated a multifaceted AIDS prevention program to increase condom use among sex workers in the city of Chiang Mai, Northern Thailand. SUBJECTS AND METHODS: A year-long intervention targeted sex workers, brothel owners and clients, promoted cooperation between these groups and the public health office and established a free condom supply for sex establishments. Nearly 500 women from 43 establishments took part in the program, encompassing nearly all direct sex workers in urban Chiang Mai. The intervention included repeated small-group training sessions for sex workers in which experienced women ('superstars') acted as peer educators. The 'model brothel' component encouraged all brothel owners in Chiang Mai to insist on mandatory use of condoms by sex workers and to encourage clients to use condoms. Before and after the intervention, specially trained volunteers posing as clients tested a subsample of sex workers to see whether they insisted on condom use. RESULTS: The intervention was well received by sex workers and obtained strong support and cooperation from brothel owners. Before the intervention, only 42% (10/24) of women surveyed by volunteers posing as clients refused to have sex without a condom, even when the client insisted and offered to pay three times the usual fee. Following the program, 92% (72/78) refused; 1 year later, 78% (69/85) refused during the same scenario. CONCLUSIONS: An innovative program directly involving sex workers as peer educators and enlisting the support of brothel owners and operators can result in improved condom use over time. Lessons learned from this program may be applicable elsewhere.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Results of a model AIDS prevention program for high school students in the Philippines.

OBJECTIVES: To describe the sexual practices of high school students; to describe the process of development of a school-based AIDS prevention program; and to evaluate the effect of this program on students' AIDS-related knowledge, attitudes and AIDS-preventive behaviors. SUBJECTS AND METHODS: A cluster-randomized, controlled trial with pretest/post-test evaluation was conducted in four demographically similar public high schools in a semi-urban district of Metro Manila, the Philippines. Of 845 high school students who participated in the baseline survey, 804 (95%) completed a postintervention questionnaire. INTERVENTION: An AIDS prevention program was developed by public high school teachers together with local AIDS experts, social scientists and health educators. The teacher-led AIDS program was designed to provide students with accurate information about AIDS, particularly in dispelling misconceptions about casual contagion, to foster positive attitudes towards people with AIDS and to develop skills aimed at clarifying values and assessing intended behavior. RESULTS: At baseline, 11% of students (20% of males and 4% of females) reported ever having had sexual intercourse (mean age 14 years). Among these, condom use was low (24%). After implementation of the AIDS prevention program, statistically significant effects favoring the intervention group were observed in knowledge and attitudes towards people with AIDS. While there was no statistically significant overall effect on intended preventive behavior, the program appeared to delay the students' intended onset of sexual activity. CONCLUSIONS: A sizable number of Filipino high school students are sexually active but condom use is low. School-based AIDS prevention programs can be developed and implemented in developing countries with the assistance of school personnel to address sexual issues. Our program was successful in increasing AIDS-related knowledge and improving attitudes towards people with AIDS. Supplementation with other preventive activities may be needed to achieve lasting changes in students' risk-taking behavior.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Use of analgesics and risk of renal cell cancer.

Although heavy or long-term use of analgesics has been related to risk of renal cell cancer in several studies, evidence for such an association remains inconclusive. In a population-based case-control study including 440 renal cell cancer cases, spouses of an additional 151 cases, and 691 controls, we assessed renal cell cancer risk associated with lifetime consumption among those who reported during in-person interviews regular (at least 2 or more times per week for 1 month or longer) use of analgesics. Odds ratios (OR) were computed using logistic regression analyses. No excess risk was associated with regular use of aspirin, acetaminophen, phenacetin or combinations of these agents, nor did risks rise with increasing cumulative intake of these analgesics. A non-significant increased risk (OR = 2.1, 95% CI = 0.6-6.9) was observed among women who used only acetaminophen-containing analgesics, but little excess was seen in men. Earlier studies reported a link to phenacetin-containing analgesics, but no one reported exclusive use of phenacetin-containing drugs in our study. The findings suggest that use of analgesics is not likely to play a major role in renal cell cancer development and that for cases diagnosed in the late 1980s or later, after the earlier withdrawal of phenacetin-containing drugs from the market, a hazard from this analgesic no longer exists.

Acetaminophen↗
PubMed1994

Protein intake and risk of renal cell cancer.

BACKGROUND: Renal cell cancer, although still relatively uncommon, has been increasing in incidence in the United States and other countries around the world. PURPOSE: Since previous studies have suggested an association with high intake of meat, we sought to further examine the role of diet in renal cell cancer risk. METHODS: Patients with histologically confirmed renal cell cancer that had been diagnosed between July 1, 1988, and December 31, 1990, were identified through the Minnesota Cancer Surveillance System, a statewide cancer registry. The patients eligible for inclusion in this study were white residents of Minnesota between 20 and 79 years of age. Control subjects were selected from the general population of Minnesota residents; subjects under age 65 were selected by use of a random-digit-dialing method and those 65 years or older were sampled from the Health Care Financing Administration files. Population-based control subjects were frequency-matched to cases by sex and 5-year age groups. A total of 690 patients and 707 control subjects were interviewed. Patients and control subjects were similar in distribution by sex, age, and educational level. Usual adult dietary intakes were assessed by questionnaire, and odds ratios were calculated by logistic regression analyses. RESULTS: Significantly increased risks of renal cell cancer were observed with increasing consumption of several food groups, including red meat (P for trend = .05), high-protein foods (P = .01), and staple (grains, breads, and potatoes) foods (P = .009). When examined by macronutrient status, risks increased monotonically with the amount of protein intake, from 1.2 (95% confidence interval [CI] = 0.7-1.9) to 1.4 (95% CI = 0.8-2.5) and 1.9 (95% CI = 1.0-3.6) (P for trend = .03) in the second, third, and fourth quartiles of intake, respectively, after adjustment for age, sex, caloric intake, body mass index, and cigarette smoking. No significant or consistent associations were detected with the intake of other dietary nutrients or beverages. CONCLUSION: Although an independent effect of dietary protein has not been previously associated with renal cell cancer, high protein consumption has been related to development of other chronic renal conditions that may predispose an individual to this cancer. IMPLICATION: These findings should prompt further study of dietary protein and its potential contribution to the origins of renal cell cancer.

Adult↗
PubMed1994

An epidemiologic study of carpal tunnel syndrome and hand-arm vibration syndrome in relation to vibration exposure.

No Minnesota workers' compensation claims have been filed for permanent partial disability benefits with a diagnosis of hand-arm vibration syndrome (HAVS). A cross-sectional study was undertaken to evaluate 519 compensation claimants following carpal tunnel surgery. Workers with significant vibration exposure and symptoms compatible with HAVS were identified within the group. The results show that some workers are not diagnosed as having HAVS even though they meet the diagnostic criteria. This suggests that HAVS should be considered in the differential diagnosis when a worker presents with neural and/or vascular symptoms of the hands and fingers.

Adolescent↗
PubMed1994

Evaluating a school-based intervention for STD/AIDS prevention in Peru.

PURPOSE: In a context of increasing HIV/STD risks among adolescents in Latin America, new conceptions of sequential "sex education" are needed. However, older adolescents must be reached through shorter programs. A quasi-experimental study was conducted to evaluate the impact of a short school-based STD/AIDS prevention program on knowledge, attitudes, and intended behavior among secondary students in Lima. METHODS: Aimed at empowering adolescents regarding their sexuality, improving knowledge and attitudes, and developing skills and prevention-oriented behavioral intentions, the program consisted of seven weekly two-hour sessions. Cost exclusive of research expenses was $3 per student reached. RESULTS: 1213 students from 14 schools participated in either the intervention or control groups. Significant changes in knowledge on sexuality and AIDS, erotophilia, acceptance of contraception, machismo, and discrimination against persons with HIV/AIDS were found in the intervention group, as compared to the control group. Self-efficacy and prevention-oriented behavioral intentions were significantly better in the intervention group. CONCLUSIONS: Owing to its effectiveness, acceptability, and low cost, this program may become useful in reaching adolescents unable to participate in longer-term sex education programs in Peru and elsewhere.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Screening for colorectal cancer.

This paper reviews studies on fecal occult blood testing and sigmoidoscopy screening for colorectal cancer. Recently published data from a randomized controlled trial provides the first concrete evidence that annual screening for fecal occult blood can reduce colorectal cancer mortality by at least 33%. These results are corroborated by a nonrandomized but controlled study that showed a 43% colorectal cancer mortality reduction with early detection through fecal occult blood testing and sigmoidoscopy, and by a case-control study that showed a 31% colorectal cancer mortality reduction associated with fecal occult blood testing. Persuasive data to support screening recommendations for sigmoidoscopy are not yet available; however, results from observational studies are suggestive and should stimulate further research to assess the benefit of sigmoidoscopy screening.

Adult↗
PubMed1993

Reduced risk of large-bowel adenomas among aspirin users. The Polyp Prevention Study Group.

BACKGROUND: Epidemiological studies have indicated that aspirin consumption can lower the risk of large-bowel cancer. These studies are not entirely consistent, however, and their interpretation has been complicated by the possibility that cancer symptoms may have led patients to avoid aspirin or that aspirin may have influenced cancer diagnosis and treatment. PURPOSE: Our purpose was to determine the effect of aspirin on risk of large-bowel neoplasms in a study in which aspirin use would not be expected to affect tumor detection and tumor-related symptoms would not likely influence aspirin use. A less complicated assessment of the relationship between aspirin and large-bowel tumors should thus be possible. METHODS: We studied 793 patients enrolled in a clinical trial of nutrient supplements to prevent large-bowel adenomas. Unlike invasive cancers, adenomas usually do not cause symptoms or detectable gastrointestinal bleeding; thus, adenomas are unlikely to influence aspirin use. Each patient had at least one large-bowel adenoma diagnosed and removed shortly before study entry and had been judged to be free of further tumors by colonoscopy. Use of aspirin was assessed by responses on questionnaires administered 6 and 12 months after enrollment. We performed complete colonoscopies on all patients 1 year after they entered the study and removed all polyps. RESULTS: Patients who reported taking aspirin on both questionnaires (consistent users) had a lower risk of new adenomas at their 1-year follow-up colonoscopy (odds ratio = 0.52; 95% confidence interval = 0.31-0.89) compared with patients who did not report using aspirin on either of the questionnaires. The apparent protective effect of consistent aspirin use was present among both men and women and did not appear to be influenced by the number of prior adenomas. CONCLUSIONS: These data further support the hypothesis that aspirin has an antineoplastic effect in the large bowel. Nevertheless, the question of whether aspirin should be used to prevent large-bowel tumors would be best answered by a randomized controlled clinical trial specifically designed to address this issue.

Adenoma↗
PubMed1993

Reducing mortality from colorectal cancer by screening for fecal occult blood. Minnesota Colon Cancer Control Study.

BACKGROUND: Although tests for occult blood in the feces are widely used to screen for colorectal cancers, there is no conclusive evidence that they reduce mortality from this cause. We evaluated a fecal occult-blood test in a randomized trial and documented its effectiveness. METHODS: We randomly assigned 46,551 participants 50 to 80 years of age to screening for colorectal cancer once a year, to screening every two years, or to a control group. Participants who were screened submitted six guaiac-impregnated paper slides with two smears from each of three consecutive stools. About 83 percent of the slides were rehydrated. Participants who tested positive underwent a diagnostic evaluation that included colonoscopy. Vital status was ascertained for all study participants during 13 years of follow-up. A committee determined causes of death. A single pathologist determined the stage of each tissue specimen. Differences in mortality from colorectal cancer, the primary study end point, were monitored with the sequential log-rank statistic. RESULTS: The 13-year cumulative mortality per 1000 from colorectal cancer was 5.88 in the annually screened group (95 percent confidence interval, 4.61 to 7.15), 8.33 in the biennially screened group (95 percent confidence interval, 6.82 to 9.84), and 8.83 in the control group (95 percent confidence interval, 7.26 to 10.40). The rate in the annually screened group, but not in the biennially screened group, was significantly lower than that in the control group. Reduced mortality in the annually screened group was accompanied by improved survival in those with colorectal cancer and a shift to detection at an earlier stage of cancer. CONCLUSIONS: Annual fecal occult-blood testing with rehydration of the samples decreased the 13-year cumulative mortality from colorectal cancer by 33 percent.

Aged↗
PubMed1993

Sample sizes for prevention trials have been too small.

Planners of several large prevention trials have overestimated the expected incidence of events in the control group, largely because they failed either to recognize or to adequately correct for various effects of population selection. Consequently, the studies have been too small in size or too short in duration to achieve their stated objectives. The selection effects include those engendered by the choice of the target population, the self-selection of volunteers, and protocol exclusions. This paper presents a taxonomy of these effects and the likely direction of their influence on the incidence of events and on mortality rates from other causes. Little information is available to help sample-size planners in adjusting for these effects. A few studies have provided information on the extent to which control group incidence rates have fallen short of expectations. In particular, researchers from the University of Minnesota's Colon Cancer Control Study have provided a detailed comparison of event incidence and all-cause mortality rates with general population rates. (AM J Epidemiol 1993;137:797-810). Other studies should publish similarly detailed information to assist sample-size planners of prevention trials. Until more information is published, this paper provides preliminary guidelines for prevention trial sample-size planning.

Clinical Trials as Topic↗
PubMed1993

Estimating the duration of ongoing prevention trials.

The authors present a method of estimating the duration of ongoing prevention trials, showing how the method was applied to the Colon Cancer Control Study, a University of Minnesota study of occult blood testing undertaken to screen for colorectal cancer in older Minnesotans. In that study, begun in 1975 and ongoing, as in several other recent large prevention trials, it was necessary, after the start of the study, to revise upward the initial estimates of study duration derived from general population experience. The underestimates arose because the planners had not adequately taken various population selection factors into account in estimating the expected number of events in the control group. In this paper, the authors outline a method for estimating control group event rates and study duration requirements (and, in some circumstances, also sample size requirements) of prevention studies, via models of disease-specific and all-cause standardized mortality ratios which adjust for various selection effects. The authors also validate the model for disease-specific standardized mortality ratios by means of independent estimates of disease incidence and case survival.

Aged↗
PubMed1993

Data on prior pesticide use collected from self- and proxy respondents.

Proxy respondents have often been used in case-control studies of cancer and pesticides. To evaluate the effect of exposure misclassification, we compared data collected during 1981-1983 from participants interviewed for a case-control study of leukemia and non-Hodgkin's lymphoma with data collected during 1990-1991 from proxy respondents for participants who died or became incompetent since the initial interview (328 self-proxy pairs). As questions increased in detail, agreement percentages decreased. Agreement percentages were highest for demographic and general farming information (averages = 88-90%) and lowest for specific pesticide use (averages = 68-74%). Generally, odds ratios calculated from proxy respondent data were less than those from self-respondent data; however, several exceptions occurred. The findings indicate that pesticide data provided by proxy respondents will not necessarily result in the same estimate of risk and/or lead to the same conclusions as data provided by self-respondents.

Adult↗
PubMed1993

Mortality among employees of a perfluorooctanoic acid production plant.

Perfluorooctanoic acid (PFOA) has been found at low levels (10 to 100 parts per billion) in sera of the general population and at higher levels in occupationally exposed workers. Although PFOA has been reported to be a promoter of rodent hepatocarcinogenesis and to alter reproductive hormones in humans and rodents, there is little information on human health effects associated with PFOA exposure. The present study examined the relationship between PFOA and mortality using a retrospective cohort mortality design. The cohort consisted of 2788 male and 749 female workers employed between 1947 and 1983 at a plant that produced PFOA. The all-causes standardized mortality ratio was .75 (95% confidence interval [CI], .56 to .99) for women and .77 (95% CI, .69 to .86) for men. Among men the cardiovascular standardized mortality rate was .68 (95% CI, .58 to .80) and the all-gastrointestinal diseases was .57 (95% CI, .29 to .99). There was no significantly increased cause-specific standardized mortality ratio for either men or women. Ten years of employment in exposed jobs was associated with a 3.3-fold increase (95% CI, 1.02 to 10.6) in prostate cancer mortality compared to no employment in PFOA production. There were only six prostate cancer deaths overall and four among the exposed workers; thus, the results must be interpreted cautiously. If prostate cancer mortality is related to PFOA, PFOA may increase prostate cancer mortality by altering reproductive hormones in male workers.

Adult↗