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Biomedical subjects

T Hirohata

Publications and source records attributed to T Hirohata.

At least 127 records · Page 7Linked to original sources
PubMed1986

Anthropometric indicators of breast cancer risk in postmenopausal women in Hawaii.

As part of a case-control study of breast cancer in Hawaii, self-reported data on height, weight at various ages, breast size, shoe size, and triceps skinfold thickness were collected from 138 Japanese postmenopausal cases, 134 Caucasian postmenopausal cases, 154 Japanese neighborhood controls, and 142 Caucasian neighborhood controls. In a multiple covariance analysis, cases of both ethnic groups were slightly heavier (at all ages) and more obese (based on a weight-corrected-for-height index) than were controls, although none of the differences was statistically significant. Among the Japanese only, cases were also taller, had a greater body surface area (computed from the height and weight data), and had a larger shoe size than did the controls. The latter finding was statistically significant (p less than 0.05). Odds ratios were computed by multiple logistic regression analysis and revealed no additional relationships; however, there were suggested dose-response gradients for height, weight at age 20, and body surface area in the Japanese women and for breast size in the Caucasian women. A further analysis of risks based on changes in relative body weight between young adult life (age 20) and current age was also negative. Overall, these findings offer only weak support for an association between weight or obesity and breast cancer risk and suggest that anthropometric indices are at best very indirect indicators of true etiologic factors for breast cancer.

Adult↗
PubMed1986

The role of drinking and cigarette smoking in the excess deaths from liver cancer.

A long-term cohort study of 639 males in a farming area and 677 males in a fishing area in Kyushu, Japan, has been conducted to evaluate risk factors for ischemic heart disease. The present investigation utilized this long-term cohort study to assess the role of drinking and cigarette smoking habits in the causation of liver cancer. The O/E ratio (ratio of the observed to expected number of deaths) of liver cancer was 7.5 (P less than 0.001) among shochu drinkers in the fishing area. Further, a clear dose-response relationship of O/E ratio was noted: 5.7 (P less than 0.001), 7.5 (P less than 0.001) and 20.0 (P less than 0.001) for drinkers of less than 1, 1-2, and 2 or more units of shochu (a distilled alcoholic beverage made in Japan; about 25% alcohol). Although no excess risk was found among shochu drinkers in the farming area, observed and expected numbers were too small to make valid judgements. Among sake drinkers, the observed and expected numbers were very similar in both areas. Cigarette smokers in the fishing area appeared to have a high risk for liver cancer, the O/E ratio being 4.8 (P less than 0.001). However, there was no clear dose-response relationship and O/E ratios among cigarette smokers according to their drinking habits indicated no excess risk among nondrinkers. A multiple logistic regression analysis showed an insignificant effect of cigarette smoking on the development of liver cancer after adjustment for shochu drinking. These findings suggest a significant involvement of shochu drinking in the etiology of liver cancer, at least in this fishing area.

Adult↗
PubMed1986

[The immunological role of carotenoids in the prevention of cancer].

Epidemiological studies have suggested that the intake of green-yellow vegetables decrease the risk of cancer. Vitamin A, which is abundantly present in green-yellow vegetables in the form of provitamin A, was demonstrated to inhibit chemical and viral-carcinogenesis in experimental animals. However, little is known about the mechanism of anti-carcinogenic effect of vitamin A. Our data seem to support a hypothesis that vitamin A may contribute to the prevention of cancer by augmenting an immunosurveillance system. We found that vitamin A and provitamin A, beta-carotene, enhanced tumor immunity using a syngeneic murine tumor system.

Animals↗
PubMed1985

Vitamin A and tumor immunity.

Intraperitoneal administration of vitamin A into the BALB/c mice inoculated with a syngeneic fibrosarcoma, Meth A, caused a remarkable augmentation of tumor rejection. A cell-depletion technique revealed that the primary effector cells responsible for the augmented rejection were Thy-1 positive, Lyt-1 negative, Lyt-2 positive lymphocytes, suggesting the involvement of cytotoxic lymphocytes.

Animals↗
PubMed1985

Occurrence of breast cancer in relation to diet and reproductive history: a case-control study in Fukuoka, Japan.

An epidemiologic study on breast cancer in relation to diet and reproductive history was conducted with 3 populations at different levels of risk for the disease: Japanese in Fukuoka, Japan (low risk), Japanese in Hawaii (intermediate risk), and Caucasians in Hawaii (high risk). This report describes the Fukuoka portion of the study. We interviewed 212 patients with histologically confirmed breast cancer and an equal number each of hospital and neighborhood controls to determine risk factors for the disease. The results indicated that "overnutrition" (a high-fat and high-animal protein diet) was not statistically associated with the disease. As noted in previous studies, age at the first birth was positively related to the disease; those women who gave birth to their first child when they were 35 or more years of age showed a relative risk of 5.0 compared with those giving birth at less than 20 years of age. A past history of both natural abortion and of benign breast disease were significantly associated with the disease. On the whole, the results obtained from this Fukuoka portion of study were in good agreement with those from the Hawaii study during which Japanese and Caucasians in Hawaii were investigated.

Adolescent↗
PubMed1985

Breast cancer in Caucasian and Japanese women in Hawaii.

This case-control study included 183 Japanese and 161 Caucasian patients with breast cancer and equal numbers of matched hospital and neighborhood controls. The following factors were found to be associated with increased breast cancer risk in both groups of women: family history of breast cancer, history of benign breast disease, early age at menarche, late age at first childbirth, and late menopause. We noted a weak suggestion that the patients ate more saturated fats and oleic acid and took replacement estrogens for a longer period than did the neighborhood, but not hospital, controls. However, none of these differences was statistically significant.

Adolescent↗
PubMed1985

Cancer occurrence in shipyard workers exposed to asbestos in Hawaii.

Because large numbers of persons were employed in United States shipyards during World War II, the long-term risks for cancer associated with asbestos exposure in this setting are of great concern. We report here on the mortality findings after up to 29 years of follow-up on a retrospective cohort of 7971 male Pearl Harbor Naval Shipyard workers, which included more than 3000 men whose employment period spanned the World War II years. Compared with the general population of Hawaii, workers in the shipyard cohort had no increase in total mortality or in total cancer mortality irrespective of the duration of their exposure. However, the risk ratio for lung cancer among workers with at least 15 years of asbestos exposure was 1.4 overall (95% confidence interval, 1.0 to 2.0) and 1.7 for those with a latency interval of 30 or more years (95% confidence interval, 1.0 to 2.5). In addition, seven mesotheliomas occurred between 1977 and 1982 in a subset of the cohort, consisting of 7029 Hawaii residents who are being followed prospectively for cancer incidence. This represented an incidence of 67.3 per million men per year, compared with a rate of 5.8 for the state as a whole. These results suggest that the long-term relative increase in risk for mesothelioma may be even greater than that for bronchogenic carcinoma in this and other cohorts of United States shipyard workers exposed to asbestos.

Adult↗
PubMed1984

Breast cancer in two populations with different levels of risk for the disease.

Caucasian women in Hawaii have a higher risk for breast cancer than women of Japanese ancestry. In order to determine to what extent known risk factors account for the difference in risk between the two groups, a case-control study was done from 1975 to 1980. A total of 183 Japanese and 161 Caucasian breast cancer cases were interviewed along with their respective controls. The findings suggested that a positive history of benign breast disease, a family history of breast cancer, late menopause, late age at first childbirth and early age at menarche did not fully account for the difference in breast cancer risk between Caucasian and Japanese women in Hawaii. Attention needs to be focused on other factors that are under environmental influence.

Aged↗
PubMed1984

Histopathological features and their association with steroid receptors in women with breast cancer in Fukuoka, Japan.

In Fukuoka, Japan, infiltrating duct carcinoma predominated among 213 breast cancer cases, age 45 to 74. Lobular and medullary carcinomas were infrequent. About thirty three percent of the women had marked productive fibrosis, based on the UICC code type. Both rough margin and productive fibrosis of the cancer increased with age of the patients. On the contrary, most of accompanying hyperplastic lesions decreased with age. The difference was significant for cystic formation between 10-year age groups of 45-54 and 55-64 (chi 2 = 6.61, p less than 0.02). Hormone receptors of 115 of the cases were independently measured and characterized according to histologic patterns manifesting host reaction (stromal cell infiltration and lymph node histiocytosis). Positive estrogen receptors were more frequent among ductal carcinomas with slight or no cellular reaction than those with extensive cellular reaction. The same pattern was also present for progesterone and androgen receptors. The extent of sinus histiocytosis in lymph nodes without metastasis was also inversely correlated with the presence of these hormone receptors. The correlation was significant for androgen receptor (chi 2 = 5.31, p less than 0.05). Positive estrogen receptor was more common among ductal carcinomas with prominent fibrosis than among those with minimal fibrosis.

Aged↗
PubMed1984

Inhibitory effect of gramicidin S on the growth of murine tumor cells in vitro and in vivo.

The Effect of gramicidin S (GS), a polypeptide antibiotic, on the growth of murine tumor cells such as allotransplantable sarcoma 180 (S180) and Ehrlich ascites carcinoma (EAC) and Meth A fibrosarcoma (Meth A) was studied. GS inhibited the proliferation of EAC cells in culture and its effect on cell viability was dependent on the concentration of GS. On exposure to GS at concentrations ranging from 1 to 100 micrograms/ml for 10 min, EAC cells lost their transplantability in ddY mice depending on the concentration of GS. In particular, the transplantability of EAC cells was completely missing on exposure to GS at a concentration of 100 micrograms/ml. In the in vivo experiments, a daily intraperitoneal injection of GS exhibited a high inhibitory effect not only on the growth of subcutaneously implanted S180 in ICR mice but on the growth of subcutaneously implanted syngeneic Meth A in BALB/c mice. In the studies using radioactively labeled DNA, RNA and protein precursors, GS at high concentrations inhibited the incorporation of all the precursors into EAC cells.

Animals↗
PubMed1983

Reproducibility of a diet history questionnaire in a case-control study of breast cancer.

The reproducibility of a diet history questionnaire was assessed as part of a case-control breast cancer study in Caucasian and Japanese women in Hawaii. The method was designed to estimate the intakes of total and saturated fat, cholesterol, and animal protein during a usual week before symptoms or diagnosis of disease in cases, and during a usual recent week in controls. Except for the time period of reference, the dietary technique was identical for all cases and controls. A subsample of 61 Japanese women (19 cases and 42 controls) and 56 Caucasian women (23 cases and 33 controls) participated in the dietary reinterview conducted within 3 months of the first interview. The mean difference in intake between the two interviews was small and not statistically significant (p greater than 0.05) for all four nutrient items among Japanese cases and controls and Caucasian cases, whereas the mean difference for all four nutrients was substantial and statistically significant (p less than 0.05) among the Caucasian controls. The intraclass correlation and the product-moment correlation were moderately high for all four nutrient items among Japanese cases and controls and Caucasian cases, but not among Caucasian controls. These findings indicate that the diet history method is reasonably reproducible in three of the four groups of studied subjects. Possible reasons for the poor reproducibility among Caucasian controls are discussed.

Asian↗
PubMed1983

Myocardial protection during cardiac ischemia by coronary perfusion with cold lactated Ringer's solution plus mannitol.

This experimental and clinical study evaluates the degree of myocardial protection afforded by coronary perfusion with cold lactated Ringer's solution plus mannitol. In the experimental study, diluted blood at 30 degrees C (Control G.), lactated Ringer's solution at 4 degrees C (G. A), 1,000 ml lactated Ringer's solution plus 200 ml of 20% mannitol at 4 degrees C (G. B), and 1,000 ml lactated Ringer's solution plus 500 ml of 20% mannitol at 4 degrees C (G. C) were used for coronary perfusion. The myocardial-protecting effect of each perfusate was evaluated by examining serum isoenzymes (CPK-MB, LDH1+2), left ventricular function (Vmax, LVEDP, CO), and the ultrastructure of myocardium. there were no significant differences in myocardial changes between the control group, G. A and G. B. Left ventricular enddiastolic pressure increased significantly in G. A and a significant increase in CPK-MB was seen in G. C. Mitochondrial scores for each group were 98 (Control G.), 86 (G. A), 93 (G. B), and 51 (G. C). Minimal myocardial change was seen in G. B. In the clinical study aortic root perfusion with cold lactated Ringer' s solution (400 m Osm) under aortic cross clamping (27-144 min) was employed in 25 patients. They all survived and CPK-MB returned to preoperative values within 49 hours after operation. In 6 cases, the ultrastructure of left ventricular papillary muscle was examined. It was confirmed that no significant mitochondrial changes developed during aortic cross-clamping.

Animals↗
PubMed1983

Role of diet in cancer incidence in Hawaii.

Incidence rates for many sites of cancer show wide variations among the main ethnic groups in Hawaii (Caucasians, Japanese, Chinese, Filipinos, and Hawaiians). Major shifts in cancer rates among migrants to the islands suggest that environmental factors are at least in part responsible for these variations. One prominent area of difference among these ethnic populations is their diets, which can vary substantially, not only in the consumption of particular food items but also in mean nutrient intakes. In aggregate correlational analyses based on data from representative samples of these ethnic groups and corresponding population-based cancer incidence rates, we found significant associations between ethnic-sex-specific intakes of dietary fat (including total fat, as well as animal, saturated, and unsaturated fats) and breast, endometrial, and prostate cancers. Animal protein intake showed associations similar to those for dietary fat, but these two nutrients were highly correlated in the data. Cholesterol intake showed significant correlations with lung and laryngeal cancers. Analyses of both nutrient and food item data suggested an association of stomach cancer incidence with the consumption of fish products, particularly dried/salted fish, and with a lower intake of vitamin C. Preliminary findings from ongoing case-control studies showed the following relationships: an inverse association between lung cancer risk and the intake of food sources of vitamin A, especially foods containing carotenes; an inverse association between cancers of the lower urinary tract and vitamin A consumption, especially from supplements; a positive association between prostate cancer risk and dietary fat intake in men above age 69, but not in younger men; and a positive association between breast cancer risk and the intake of dietary fat (particularly saturated fat) and animal protein in postmenopausal women, especially the Japanese. Two large cohorts (50,000 and 5,000 subjects) on whom dietary information was collected between 1975 and 1980 are being followed prospectively for their occurrence of cancer.

Age Factors↗
PubMed1982

Combined treatments with vitamin A and 5-fluorouracil and the growth of allotransplantable and syngeneic tumors in mice.

The combined effect of retinol palmitate (RP) and 5-fluorouracil (FUra) was examined with the use of allotransplantable and syngeneic murine tumor systems. The ip combined administration of RP (5,000 IU/kg/day) and FUra (5 mg/kg/day, 20 mg/kg/day, or 20 mg/kg/every 3d day) suppressed the tumor growth in ICR/JCL mice given sc inoculations of 5 X 10(6) allotransplantable sarcoma 180 cells and prolonged the survival time of mice inoculated ip with 10(7) tumor cells, as compared with the survival time of mice given the single administration of either RP or FUra. Similar results were obtained when BALB/c mice were inoculated sc with a syngeneic BALB/c Meth A fibrosarcoma and treated with RP (5,000 IU/kg/day) and FUra (20 mg/kg/every 3d day). The growth of Meth A implanted on day 10, as a rechallenge, was significantly suppressed in the group pretreated with RP alone or both RP and FUra for 9 days from day 1. The growth of Meth 1, another syngeneic tumor of BALB/c origin, inoculated on day 10 as a rechallenge tumor was unaffected by the treatment with RP and/or FUra. An immune response to tumor-specific antigens seemed to be involved in the combined effects of these two drugs.

Animals↗
PubMed1981

Association of diet and place of birth with stomach cancer incidence in Hawaii Japanese and Caucasians.

Stomach cancer incidence rates were compared among four groups: Japanese in Japan, Japanese in Hawaii, Caucasians in Hawaii, and all American whites. The highest rates at all ages occurred in the Japan Japanese, followed next by the Hawaii Japanese. Hawaii Caucasians tended to have similar age-specific rates to American whites in general. When the Japanese and Caucasians in Hawaii were divided by place of birth, the Japanese migrants to Hawaii had higher age-adjusted incidence rates than the Japanese born in Hawaii, while the Caucasian migrants to Hawaii (chiefly from the United States mainland) had lower rates than the Caucasians born in Hawaii. Examination of dietary data in relation to the place-of-birth-specific incidence rates showed positive association of stomach cancer with consumption of rice, pickled vegetables, and dried/salted fish, and a negative association with vitamin C intake. The results are consistent with the particular hypothesis that stomach cancer is caused by endogenous nitrosamine formation from dietary precursors, and that vitamin C may protect against the disease.

Aged↗
PubMed1981

Role of delayed hypersensitivity and cytostatic macrophages in the rejection of an allo-transplantable murine tumor.

Growth of an allo-transplantable tumor, sarcoma-180, was suppressed in ICR mice immunized with mitomycin C-treated tumor cells in Hanks' solution or heat-killed tumor cells mixed with complete Freund's adjuvant 7 days before subcutaneous inoculation of tumor cells. In those mice, cytotoxic lymphocytes were not detected in spleen, lymph node or peritoneal exudate cells before or after tumor inoculation. The activities of antibody-dependent cell-mediated cytotoxicity (ADCC) and complement-dependent cytotoxicity were not found in sera. Cytostatic activity was detected in peritoneal glass-adherent cells, but not in glass-nonadherent cells. Such an activity was also conferred on normal peritoneal glass-adherent cells by incubation with the culture supernatant of lymph node cells from preimmune mice and tumor cells. Cytostatic macrophages mediated by lymphokine-producing lymphocytes may be at least one of the main effector mechanisms in resistance against such an allo-transplantable tumor line.

Animals↗