ISSN:0163-5581    

DOI:10.1080/01635588209513743

出版商:Taylor&Francis Group    

年代:1982

数据来源: Taylor

摘要:

AbstractMice given quercetin per os at concentrations that were about 103times greater than the estimated average human intake of total flavonols were tested for mutagenicity with 2 complementary in vivo mutagenicity/carcinogenicity screening tests—the micronucleus test and the host‐mediated assay employing the Ames Salmonella tester strain TA 98 as indicator organism. No mutagenic effect was detected with either test.

ISSN:0163-5581    

DOI:10.1080/01635588209513744

出版商:Taylor&Francis Group    

年代:1982

数据来源: Taylor

摘要:

AbstractThe effect of high‐and low‐fat diets, with and without cholesterol supplementation, on the development of N‐methylnitrosourea (NMU)‐induced mammary tumors was assessed. Diets consisting of 1. high fat (HF) (20% lard), 2. HF + cholesterol, 3. low fat (LF) (4% lard) + cholesterol, and 4. LF were fed to F344 female rats (24 animals/group) 2 days after NMU administration, and cumulative mammary tumor incidence was monitored for a total of 26 weeks. Animals fed HF diets exhibited significantly greater tumor incidences and numbers of tumors/animal than did animals fed LF diets (p<.0001), regardless of whether cholesterol was present in the diet. These results are consistent with the hypothesis that the mammary‐tumor promoting effects of HF diets are exerted primarily by the triglyceride fraction rather than by the nonsaponifiable (sterol) fraction of total dietary fat.

ISSN:0163-5581    

DOI:10.1080/01635588209513745

出版商:Taylor&Francis Group    

年代:1982

数据来源: Taylor

摘要:

AbstractThe effects of combined nutritional support (parenteral, enteral, and oral) were measured in cancer patients unable to maintain normal alimentation. Changes in body composition were quantified by measurement of total body levels of nitrogen, potassium, water, and fat. The protein‐calorie intake of the patients was also evaluated by dietary survey (4‐day recall). Standard anthropometric and biochemical measurements for nutritional assessment were obtained for comparison.The dietary evaluation indicated that the dietary supplementation for all patients was more than adequate to meet their energy requirements. Almost all patients gained weight on the combined nutritional support regimens. Determination of body composition indicated that change in body weight was equal to the sum of the changes in body protein, total body water, and total body fat. The findings from the anthropometric nutrition indices (arm muscle circumference and triceps skinfold) were consistent with the results of the body composition study.Information on the nature of the tissue gained was obtained by comparison of body composition data with the ratio of protein:water:lean body mass for normal tissue. The mean gain of protein in the cancer patients was quite small (0.3–0.6 kg). The main change in body weight appeared to be the result of gains in body water and body fat. The total body nitrogen to potassium ratio served to define the extent of tissue anabolism following hyperalimenlation. The ratio dropped in the cancer patients following hyperalimentation toward the value of the control subjects on ad libidum diets. The body compartment techniques described have demonstrated their usefulness in determining the effects of hyperalimentation on cancer patients.

ISSN:0163-5581    

DOI:10.1080/01635588209513746

出版商:Taylor&Francis Group    

年代:1982

数据来源: Taylor

摘要:

AbstractThe dietary pattern, fecal bile acid and neutral sterol concentrations, and the bacterialβ‐glucuronidase activity of 2 population groups with a varied risk for colon cancer development (i.e., a high‐risk population in the metropolitan New York area and an intermediate‐risk population in Umea, Sweden) were investigated. The average daily intake of dietary protein was the same in the 2 groups, but the fat intake was higher in Umea than in New York. The daily total fiber intake was also higher in Umea, as was the daily total stool output. The concentration of fecal secondary bile acids andβ‐glucuronidase activity was lower in Umea than in New York, but the total daily excretion of these constituents was the same in both groups. The data suggest that one of the factors contributing to the lower risk of colon cancer in Umea, despite the high dietary fat intake, is the high intake of dietary whole grain and cereal fiber, which leads to an increase in stool bulk, thus diluting and/or binding promoters.

ISSN:0163-5581    

DOI:10.1080/01635588209513747

出版商:Taylor&Francis Group    

年代:1982

数据来源: Taylor

摘要:

AbstractMice fed vitamin E at a level of 0.5 g DL‐α‐tocopheryl acetate/kg diet demonstrated decreased incidence and rate of appearance of tumors produced by transplanted sarcoma cells (K3T3), compared to control groups fed diets without the vitamin supplement. Protection was dependent on the degree of unsaturation of dietary fat and on the size of the tumor cell challenge. When vitamin E was increased 10‐fold (to 5 g/kg diet), the protective effect was no longer observed. Protection may be mediated through the host immune system, because sublethal, whole‐body X‐irradiation abrogated differences in tumor development between the + E and the‐E mice. Studies with in vitro immunization showed that treatment of the K3T3 cell with vitamin E enhanced its ability to induce a cytotoxic response. It appears that the direct effect of vitamin E is on the tumor cell rather than on the immune system, since spleen cells from mice fed diets with and without vitamin E supplementation were indistinguishable in their response to untreated K3T3 cells. K3T3 cells treated with excessive levels of vitamin E were unable to induce a cytotoxic response, a result that correlates with the loss of protection against tumor development when massive doses of vitamin E were fed.

ISSN:0163-5581    

DOI:10.1080/01635588209513748

出版商:Taylor&Francis Group    

年代:1982

数据来源: Taylor

摘要:

AbstractIn this study, the effect of tumor presence on the concentration of vitamin E in the liver, spleen, and kidney of BALB/c mice was measured, and the influence of the degree of fat saturation was assessed. In mice fed diets deficient in vitamin E, the presence of a transplanted sarcoma in the thigh significantly increased the concentration of the vitamin in all 3 organs. This was true whether the fat was saturated or unsaturated (hydrogenated coconut oil [HCO] or corn oil [CO], respectively). The tumor itself was generally lower in tocopherol than were other tissues of the tumor‐bearing host. In mice fed diets containing vitamin E, the tumor increased the vitamin content in some organs but not others. Only in the kidney of tumor‐bearing mice fed the HCO±E diet was there a significantly decreased content of the vitamin. A comparison of the spleen tocopherol content with mitogenesis by concanavalin A revealed a positive correlation, which explains why the spleens of tumor‐bearing mice fed a diet deficient in vitamin E exhibited higher mitogenic activity than the spleens of normal mice fed the same diet (namely, the spleens from tumor‐bearing mice had a higher content of tocopherol).

ISSN:0163-5581    

DOI:10.1080/01635588209513749

出版商:Taylor&Francis Group    

年代:1982

数据来源: Taylor

摘要:

AbstractA study was conducted to determine whether 1,2‐dimethylhydrazine (DMH), a potent colon carcinogen, is activated to a more potent mutagen by the drug‐metabolizing system of the colonic mucosa and to determine the extent to which this metabolism is modified by lipids in the diet. DMH‐treated rats fed a diet enriched with 10% corn oil exhibited markedly elevated colonic enzyme levels for mutagen production. This diet also produced the greatest number of animals with colon tumors, when compared with diets containing other levels and sources of lipid. The potential risk of a diet in which unsaturated fat is the sole source of lipid is underlined.

ISSN:0163-5581    

DOI:10.1080/01635588209513750

出版商:Taylor&Francis Group    

年代:1982

数据来源: Taylor

摘要:

AbstractIn order to examine the nutritional status of the population of Linxian (in Henan, China) known to be at high risk for esophageal cancer (EC), we analyzed blood samples and conducted 3‐day dietary surveys on 3 groups of normal adults, age 40–50, from Henan province. Two groups were from Linxian, where the EC mortality rate is about 138/100,000 (Group C, consisting of volunteers with a family history of EC, and Group NC, consisting of those who did not have a family history of EC). The third group, Group F, was from Fanxian, where the EC mortality rate is about 24/100,000. The average plasma retinol level was found to be about 0.27μg/ml in all 3 groups; about 13%‐20% of the individuals had a level<0.2μg/ml. The average plasma carotene level of all 3 groups appeared to be adequate, ranging from 0.5–1.0μg/ml. About 23% of the subjects in both Groups C and NC had low (<2μg/ml) plasma ascorbate levels; in Group F, 16% had low ascorbate levels. Less than 12% of the individuals in each of the 3 groups had erythrocyte glutathione reductase activation coefficients<1.2, indicating a widely occurring riboflavin deficiency. Consumption of alcoholic beverages was not found to be a contributing factor to EC. The results of the present study reveal a deficiency of vitamins in the study populations, but do not indicate that the average nutritional status of the volunteers in Group C was worse than that of Groups NC and F with regard to vitamin A, ascorbate, and riboflavin.

ISSN:0163-5581    

DOI:10.1080/01635588209513751

出版商:Taylor&Francis Group    

年代:1982

数据来源: Taylor

ISSN:0163-5581    

DOI:10.1080/01635588209513742

出版商:Taylor&Francis Group    

年代:1982

数据来源: Taylor