摘要:

AbstractPlasma and dietary levels of retinol andβ‐carotene were evaluated in a consecutive series of 47 females with histologically proven primary lung cancer and 159 nonneoplastic hospital controls. The dietary questionnaire included 69 different items: special care was given to foods rich in vitamin A and seasonal foods (e.g., vegetables and fruits), whereas serum analysis was focused on retinol andβ‐carotene.Age‐adjusted mean values for cases and controls were, respectively, 458.3 vs. 551.3 mg for plasma retinol, 276.1 vs. 390.1 mg for plasma carotene; 598.1 vs. 820.6 mg for daily retinol, and 628.0 vs. 882.5 mg for dietary carotene.The odds ratios for low vs. high fertile, adjusted for age, smoking, retinol or carotene, cholesterol, and triglycerides by multivariate analysis were, respectively, 1.13 for plasma retinol, 5.04 for plasma carotene, 3.27 for dietary retinol, and 2.93 for dietary carotene. For all the ex‐amined items, there was a trend of increased risk for the second and third tertile, and statistical significance was reached for plasmaβ‐carotene (p<0.05).The hypothesis that a higher risk of lung cancer is related to a low vitamin A consumption is supported by these data.

ISSN:0163-5581    

DOI:10.1080/01635588709513955

出版商:Taylor&Francis Group    

年代:1987

数据来源: Taylor

摘要:

AbstractA case‐control study was carried out in the populations of two Belgian provinces that differed in food consumption habits, particularly fat intake. There were 453 colonic and 365 rectal cancer cases and 2,851 population controls.There were no significant differences in the average intake of the major nutrients, with the exception of carbohydrates; patients had a larger intake, limited to oligosaccharides. In both provinces, in males and females having cancer of the colon or the rectum, the intake of linoleic acid was lower than among controls; for dietary fibers, a smaller intake was observed among patients in one province.The relative risks were computed for four levels of daily intake of each nutrient. A positive trend was found for oligosaccharides in all subgroups, and a negative trend was found for poly‐saccharides, the latter for colon cancer patients only. There was a constant and significant negative trend for linoleic acid, with a similar negative trend for dietary fiber. None of these trends were affected by further adjustment for total calorie intake.For several vitamins and minerals, less marked, less constant effects were observed. They tended to be negative for vitamin B1, vitamin B6, and iron; they were positive for retinol and vitamin B2.

ISSN:0163-5581    

DOI:10.1080/01635588709513956

出版商:Taylor&Francis Group    

年代:1987

数据来源: Taylor

摘要:

AbstractThe modifying effect ofβ‐carotene on benzo[a]pyrene (BP)‐induced tumors of the respiratory tract was investigated in Syrian hamsters. Groups of hamsters were fed a semisynthetic diet supplemented with either no or 56 mg/kgβ‐carotene. Respiratory tract tumors were induced by intratracheal instillation of BP attached to ferric oxide. Theβ‐carotene and vitamin A contents of the liver were increased in the highβ‐carotene group, but the serumβ‐carotene levels were very low when compared with those commonly observed in humans.β‐Carotene supplementation did not affect the tumor response of the respiratory tract. Neither the incidence and severity of preneoplastic changes were influenced. However, there was a statistically significant inverse relationship between serum retinol content and the presence of respiratory tract tumors in survivors, regardless of the dietary treatment.

ISSN:0163-5581    

DOI:10.1080/01635588709513957

出版商:Taylor&Francis Group    

年代:1987

数据来源: Taylor

摘要:

AbstractWe evaluated the risk of breast cancer in relation to the frequency of consumption of a few selected dietary items. Data were used from a case‐control study of 1,108 histologically confirmed breast cancer patients and 1,281 control subjects who were in the hospital for acute conditions unrelated to any of the established or suspected risk factors for breast cancer. Moderately elevated risk estimates were associated with higher levels of fat consumption in seasonings [butter, margarine, and oil, relative risk (RR) = 1.34, 95% confidence interval (CI) = 1.06–1.71] and meat (RR = 1.36, 95% CI = 1.12–1.65), whereas a reduced risk (RR = 0.42, 95% CI = 0.34–0.51) was associated with a more frequent green vegetable consumption. It was not possible to show that these associations were incidental, because allowance for several identified potential confounding factors, including the major identified or potential risk factors for breast cancer, did not materially modify the risk estimates. Further, no appreciable interaction emerged with age or menopausal status, because the diet‐related risk estimates were similar in pre‐or postmenopausal women. However, the implications of these findings in terms of specific micronutrients (e.g., retinal orβ‐carotene) and biological correlates are still unclear. Alcohol consumption was significantly greater among breast cancer cases, with a multivariate risk estimate of 2.92 for the highest level. Thus, the present findings confirm that various aspects of diet may influence the risk of breast cancer, although the small amount of available knowledge does introduce serious uncertainties in any discussion of the potential implications in terms of prevention on a public health scale.

ISSN:0163-5581    

DOI:10.1080/01635588709513958

出版商:Taylor&Francis Group    

年代:1987

数据来源: Taylor

摘要:

AbstractAfter being maintained on a vitamin A‐deficient or complete diet for a period of five weeks, male Sprague‐Dawley rats were subjected to a two‐thirds partial hepatectomy (PH) or sham operation. The vitamin A content of the liver of vitamin A‐deficient, PH rats was below the limit of detection (<1μg/g liver). Rats fed the control diet and subjected to PH had hepatic levels of vitamin A that were 37% and 49% lower 48 and 72 hours after surgery, respectively, when compared with sham‐operated controls. Hepatic microsomal cytochrome P‐450 levels were significantly reduced in PH rats fed the complete diet 48 hours after PH and in PH rats fed either the deficient or complete diet 72 hours after. Vitamin A deficiency alone significantly reduced cytochrome P‐450 levels. A combination of vitamin A deficiency and PH had the most dramatic effect on cytochrome P‐450 and aminopyrine N‐demethylase, which reduced the activity to approximately 50% of the activities found in the sham‐operated control group. PH resulted in the greatest reduction in the rate of disappearance of benzo[a]pyrene in the presence of liver microsomes prepared from vitamin A‐deficient rats.

ISSN:0163-5581    

DOI:10.1080/01635588709513959

出版商:Taylor&Francis Group    

年代:1987

数据来源: Taylor

摘要:

AbstractIn a population study, 10,000 men (aged 46–48 years) were invited to a health screening program. At follow‐up, which was up to eight years later, 61 subjects had died from cancer; from 35 of these subjects, plasma samples were available that were obtained at the initial screening. These samples, together with samples from two living controls for each case, were analyzed for selenium, retinol, cholesterol, triglyceride, and a number of plasma proteins.Plasma selenium was significantly lower (p<0.05) in cases than in controls (means: 1.06 vs. 1.12μmol/l). The proportion of cases increased significantly from the highest to the lowest quintile of plasma selenium, and the relative risk for cancer death was 3.8 times higher in the lowest quintile compared with the highest. Mean plasma retinol was similar in cases (2.53μmol/l) and controls (2.56μmol/l). Cases and controls also had similar values for plasma cholesterol, triglyceride, uric acid, apolipoprotein B, orosomucoid, prealbumin, retinol‐binding protein, andβ2‐microglobulin. Apolipoprotein AI in plasma was lower among cases (p<0.025). Cases smoked significantly more than controls did (p<0.05).Data indicate that low plasma selenium was a risk factor for cancer death in middle‐aged men who lived in the same area. Further studies are necessary to establish whether differences in selenium intake, selenium metabolism, or other factors related to selenium are responsible for the relations observed. At present, the available data do not justify selenium supplementation programs in the whole population.

ISSN:0163-5581    

DOI:10.1080/01635588709513960

出版商:Taylor&Francis Group    

年代:1987

数据来源: Taylor

摘要:

AbstractThe nutritional status of three groups of postmenopausal women (age 41–80 yrs) with advanced breast cancer was investigated with special reference to vitamin B6. The interference of hormonal treatment was studied with respect to the progestin megestrol acetate (Group MA, n = 14) and the antiestrogen tamoxifen (Group TAM, n = 15) compared with untreated patients (Group U, n = 11). Healthy postmenopausal women served as controls (Group C, n = 16). Nutritional status was judged from body mass index (BMI), vitamin and trace element status, hematology, and clinico‐chemical parameters. Intake of nutrients was calculated from a food record. Hormonal status was studied by analysis of LH, FSH, and prolactin in plasma and of steroids and catecholamines and their metabolites in 24‐hour urine. Compared with values for Group C, nutrient intake, hematology, clinico‐chemical parameters, and 24‐hour urinary excretion of catecholamines and their metabolites of patient groups (U, TAM, and MA) were not significantly different. The BMI of patients was significantly higher (by about 10% 60% showed an overweight) than that of controls. With respect to fat‐soluble vitamin status, significantly lower plasma levels of vitamin A (at least 40% lower, with deficient levels in more than 50% of the patients), D (40% lower), and E (20% lower) were found for Group U. However, water‐soluble vitamin status of the four groups was fairly similar. A significantly higher excretion of xanthurenic acid in 24‐hour urine, after an oral tryptophan load, was observed for Groups TAM and MA. This is most probably the result of hormonal treatment without affecting vitamin B6status. Small, but significant, differences between groups were found for trace element status, especially with respect to lower plasma selenium of Group U (25% lower). LH, FSH, and prolactin in plasma and excretion of steroids in 24‐hour urine showed levels that could be expected for controls and for untreated and hormonally treated patients. We concluded that the nutritional status of all patients is reasonably adequate. Hormonal treatment did not influence vitamin B6status, although levels of vitamins A, D, and E and of selenium seem to be elevated.

ISSN:0163-5581    

DOI:10.1080/01635588709513961

出版商:Taylor&Francis Group    

年代:1987

数据来源: Taylor

摘要:

AbstractThe nutritional status of individuals from areas of South Africa that are known for having a high incidence of esophageal cancer was investigated. Our results show that individuals living in high‐risk areas differ significantly from those in low‐risk areas with respect to vitamins A, E, and B12in addition to folate. These results suggest that deficiencies in these nutrients may play a significant role in the etiology of esophageal cancer.

ISSN:0163-5581    

DOI:10.1080/01635588709513962

出版商:Taylor&Francis Group    

年代:1987

数据来源: Taylor

ISSN:0163-5581    

DOI:10.1080/01635588709513954

出版商:Taylor&Francis Group    

年代:1987

数据来源: Taylor