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J S Jacobson

Publications and source records attributed to J S Jacobson.

At least 37 records · Page 2Linked to original sources
PubMed1995

Coronary artery disease and colorectal neoplasia.

PURPOSE: This study was designed to determine whether patients with coronary artery disease are at elevated risk for colorectal neoplasia. METHODS: A case-control study was conducted among consecutive patients in three colonoscopy practices in New York City from 1986 to 1988. All study participants completed an interview questionnaire covering demographics, diet, environmental and behavioral exposures, family and personal medical history, and other variables. For the present study, 298 newly diagnosed colorectal adenoma cases and 107 incident cancer cases were compared with 507 colonoscoped controls without colorectal neoplasia or other significant findings on colonoscopy. Data on history of coronary artery disease (angina and/or heart attack) were obtained solely from the study participants' questionnaire responses. RESULTS: No association was observed between angina, heart attack, or either and colorectal adenomas in males. However, prior coronary artery disease was found to be associated with colorectal cancer in males more than 60 years of age and with colorectal adenomas in females aged 50 years or younger. CONCLUSION: Men with coronary artery disease may be at elevated risk for subsequent colorectal cancer. Young women with coronary artery disease also may be at elevated risk for colorectal neoplasia.

Adenomatous Polyps↗
PubMed1995

Incidence and recurrence rates of colorectal adenomas: a prospective study.

BACKGROUND/AIMS: The frequency of colorectal adenomas, the precursor lesions for most cases of colorectal carcinoma, has been generally measured as prevalence rates of adenomas at autopsy or colonoscopy. The aim of this study was to estimate the incidence rate of adenomas and compare it with the adenoma recurrence rate. METHODS: Data on colonoscopies performed in three New York City practices were collected prospectively. The cumulative rate of adenoma diagnosis on repeat colonoscopy was calculated for patients with no abnormalities on index colonoscopy ("incidence" rate) and for patients with adenomas on the index colonoscopy ("recurrence" rate). RESULTS: The cumulative incidence rate of adenomas at 36 months was 16%, and the cumulative recurrence rate at 36 months was 42% (P < 0.004). The recurrence rate was higher in patients with multiple adenomas than in those with a single adenoma on index colonoscopy, although the increase was not statistically significant. CONCLUSIONS: Although the recurrence rate has always been assumed to be elevated, this study is the first to compare the recurrence rate of adenomas with the incidence rate directly and to show that the recurrence rate is indeed elevated.

Adenoma↗
PubMed1995

The limitations of breast cancer screening for first-degree relatives of breast cancer patients.

Bitter controversy surrounds the recommendation of mammographic breast-cancer screening for women aged 40 and 49 years of average risk. This paper considers the case for screening women in their 40s with higher risk, specifically women who have one or more first-degree relatives with breast cancer. A review of the literature and of current knowledge suggests that screening such women is more cost-effective, in the sense of having a higher yield per mammogram and better predictive value, than screening women of average risk in this age group. However, there is no evidence that screening is more efficacious in reducing mortality in this subgroup than in other women in their 40s.

Adult↗
PubMed1995

An above-knee prosthesis with a system of energy recovery: a technical note.

Knee flexion to 24 degrees during early stance transforms kinetic energy into potential energy of a total center of mass (TCM) position. Flexion is controlled by the musculoligamentous apparatus. Reproduction of such flexion in a new single-axis prosthesis knee unit has minimized the metabolic energy cost to the patient by a more favorable use of gravity acting upon the prosthetic segments and the body as well as of inertia. Potential energy is stored in the spring shock absorber of the knee unit. The coefficient of energy recovery increased by 30% in comparison with a conventional above-knee prosthesis. Energy costs to the patient decrease an average of 35% during gait with the new prosthesis. The same amount of unloading during walking is typical of an intact limb. The knee unit mechanism has a link set on the axle, thus providing two joints with a common axis: a) the main joint for knee flexion to 70 degrees during swing phase and flexion to 135 degrees during sitting; b) the second joint for bending at the beginning of stance phase. Compared with conventional units, gait with the new unit displays several functional advantages: 1) normal knee kinematics with movement of a TCM along a trajectory that contributes to an easy rollover of the foot and smooth and continuous translation of the body; 2) shock absorption during early stance prevents impact from the anterior brim of the socket; 3) at mid-stance, the increase of the TCM position accumulates potential energy that results in a significant increase of the push-off force; 4) during rapid gait, the unit provides adequate resistance to knee flexion; 5) location of the joint axis in front of the line of gravity loads the prosthesis in standing, making possible unimpeded carrying of the prosthesis over the support, the lengths of the prosthetic and the intact limb being equal; in addition, it facilitates flexion before the beginning of the swing phase. Production of the units began in 1992.

Amputation Stumps↗
PubMed1994

Cigarette smoking and other behavioral risk factors for recurrence of colorectal adenomatous polyps (New York City, NY, USA).

Adenomatous polyps (hereinafter referred to as adenomas) are known precursors of colorectal cancer. Cigarette smoking has been associated with adenomas but not with colorectal cancer, while alcohol and fat intake have been associated with both adenomas and cancer in some studies. Approximately 30 percent of patients with resected adenomas develop another adenoma within three years. This case-control study explores the association of cigarette smoking with adenoma recurrence. Between April 1986 and March 1988, we administered a questionnaire to colonoscoped patients aged 35 to 84 years in three New York City (NY, USA) practices. We compared 186 recurrent polyp cases (130 males, 56 females) and 330 controls (187 males, 143 females) who had a history of polypectomy but normal follow-up colonoscopy, by cigarette-smoking pack-years adjusted for possible confounders. Risk for a metachronous or recurrent adenoma was significantly greater in the highest quartile of smokers than in never-smokers among both men (odds ratio [OR] = 1.8, 95 percent confidence interval [CI] = 1.0-3.4) and women (OR = 3.6, CI = 1.7-7.6). Adjustment for time since smoking cessation reduced risk only slightly, as did adjustment for dietary fat intake, which itself remained significant. No association was found between alcohol intake and risk of recurrence. Cigarette smokers appear to have an elevated risk of adenoma recurrence that is not eliminated entirely by smoking cessation. Intervention trials that use adenoma recurrence as an endpoint should take smoking into account.

Adenomatous Polyps↗
PubMed1994

Fatherhood and distal adenomas of the large bowel: a study of male self-defense officials in Japan.

Parity has been studied extensively as a risk factor for colorectal cancer but has not been definitively shown to be associated with altered risk. In a few studies, risk of colorectal cancer in childless men has been compared to risk in men with children, but results have not been consistent. We analyzed the association of fatherhood with risk of colorectal adenomas in male self-defense officials (ages 49-55) in Japan. The study participants received a preretirement health examination including flexible sigmoidoscopy at Self-Defense Forces hospitals in Japan from January 1991 through December 1992. The examinations identified 265 cases with rectal or sigmoid adenomas and 1480 controls with normal examinations up to 60 cm from the anus. Data on marital status, number of children, long-term work assignment away from wife and children, and other lifestyle variables were obtained by means of a self-administered questionnaire prior to physical examination. Multiple logistic regression analysis assessed the risk of adenomas in relation to number of children, marital status, long-term work assignment away from family, and military rank, with adjustment for cigarette smoking, alcohol intake, dietary variables, body mass index, and recreational physical activity. In this relatively homogeneous group, more than 98% of both cases and controls were currently married, and more than 93% had children. The adjusted odds ratio for the association of adenomas with fatherhood was 0.4 (95% confidence interval, 0.2-0.8). Marital status and work assignment away from the family were not associated with adenoma risk. These findings suggest that colorectal adenomas and perhaps cancer risk may be associated with childlessness in men.

Adenoma↗
PubMed1993

Gender and colorectal cancer.

Studies of gender differences in colorectal cancer have shown temporal shifts in incidence and site distribution which can be attributed, in part, to environmental and behavioural factors. In high-risk populations, rectal cancer and left-sided colon cancer have been more frequent in older men, whereas right-sided colon cancer has been more commonly found in older women. Among known associations with reduced colorectal cancer risk, women appear to ingest more dietary fibre, seem to benefit more from physical activity and body mass, and consume less alcohol. Although these differences may contribute to the risk differential, hormonal events during reproductive years also appear to affect women's risk at older age. The interactions of sex hormone metabolism and nutrition, including dietary fibre, in colorectal carcinogenesis provide a rewarding field for investigation.

Colonic Neoplasms↗
PubMed1987

Effect of fertilizer on the growth of radish plants exposed to simulated acidic rain containing different sulfate to nitrate ratios.

Two successive experiments were performed in the greenhouse to test the hypothesis that plant response to the amounts and ratios of sulfuric and nitric acids in rain is affected by the amount of fertilizer added to the growing medium. Radish plants, grown with different levels of N?P?K fertilizer, were given ten 1-h exposures over a 3-week period to simulate acidic rain at pH values from 2.6 to 5.0 and sulfate to nitrate mass ratios from 0.3 to 7.5. Increased acidity of simulated rain reduced plant growth, with a greater depression of hypocotyl mass than shoot mass. The reverse growth response occurred with increased supply of fertilizer: plant biomass rose with a larger increase in shoot mass than hypocotyl mass. In one experiment, plants that received a greater supply of fertilizer exhibited more obvious reductions in growth of hoots at the higher levels of acidity of simulated rain. There were no significant effects of sulfate to nitrate ratios in simulated rain on plant growth, nor any effect of this ratio on the response of shoots and hypocotyls to acidity of simulated rain. Addition of fertilizer had no effect on plant response to sulfate to nitrate ratios. These results do not support the hypothesis that nutrient-deficient plants are either more or less responsive to sulfate and nitrate in rain than plants grown with optimal supplies of nutrients. They support previous results indicating no effects of sulfate to nitrate ratio in simulated acidic rain on plant growth. The results also suggest that the greatest risk of harmful effects on vegetation may come from the combination of high sulfate and high acidity in rainfall.

Journal Article↗