White blood cell DNA adducts and fruit and vegetable consumption in bladder cancer.
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The 'Mediterranean diet', a diet rich in cereals, fruit and vegetables, has been associated with lowering the risk of a variety of cancers of the digestive tract and the bladder. In a previous study, we showed that the high phenolic content these dietary components produce in the urine could be associated with higher antimutagenic properties of the urine and lower arylamine-DNA adducts in exfoliated bladder cells. We have conducted a case-control study on 162 bladder cancer patients and 104 hospital controls. Total aromatic DNA adducts were measured in white blood cells (WBC) of all subjects by (32)P-post-labelling. Genetically based metabolic polymorphisms were analysed by PCR-RFLP (NAT2, GSTM1, GSTT1, GSTP1, COMT and NQO1). All subjects were interviewed about their tobacco use, dietary habits and other risk factors. The odds ratio (OR) for the risk of bladder cancer according to the presence/absence of WBC DNA adducts (detection limit 0.1 RALx10(8)) was 3.7 [95% confidence interval (CI) 2.2-6.3] and a dose-response relationship with levels of adducts was apparent. The association between case/control status and the presence of WBC DNA adducts was significantly stronger in the subjects who consumed fewer portions of fruit or vegetables per day (OR 7.80, 95% CI 3.0-20.30 for 0-1 portions of vegetables) than in the heavy consumers (OR 4.98 for consumers of 2 portions daily, OR 1.97 for consumers of > or =3 portions; similar but lower estimates were found for the intake of fruit). No association was noticed between tobacco smoking and WBC DNA adducts. Only NAT-2, among the several genotypes considered, was associated in a statistically significant way with the risk of bladder cancer (OR 1.72, 95% CI 1.03-2.87) and with the levels of WBC DNA adducts. Our report suggests that fruit and vegetables could protect against bladder cancer by inhibiting the formation of DNA adducts. (+info)
Role of dietary factors in ethnic differences in early risk of cardiovascular disease and type 2 diabetes.
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BACKGROUND: The disparity in the prevalence of cardiovascular disease and type 2 diabetes between African Americans and whites has been well established, and ethnic differences in several risk factors for these diseases are evident in childhood. OBJECTIVE: The current study explored whether dietary factors explain ethnic differences in serum lipids and insulin profiles in children, independent of body composition and social class background. DESIGN: The sample included 95 African American and white children (mean age: 10.0 y). Macronutrient and food group intakes were derived from three 24-h recalls. Cardiovascular disease and type 2 diabetes risk were determined on the basis of total cholesterol, triacylglycerol, insulin sensitivity (S(i)), and acute insulin response (AIR). Data were analyzed by using t tests, analysis of covariance, and multiple regression. RESULTS: African American children had lower triacylglycerol (P < 0.01), lower S(i) (P < 0.001), and higher AIR (P < 0.001) than whites. Intake of fruit and vegetables was significantly higher, and dairy intake lower, in African American than in white children after adjustment for social class and total energy intake. Several direct relations were observed between diet and insulin action: carbohydrate and fruit intakes were positively associated with S(i) (P = 0.02), and vegetable intake was negatively associated with AIR (P = 0.01). However, neither macronutrient nor food group intake accounted for the ethnic differences in triacylglycerol and AIR. CONCLUSIONS: The African American children in our sample showed a greater disease risk than did the white children, even after body composition, social class background, and dietary patterns were adjusted for. (+info)
Antioxidant intakes and smoking status: data from the continuing survey of food intakes by individuals 1994-1996.
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BACKGROUND: Cigarette smoking is a major risk factor for several chronic oxidative diseases that can be ameliorated by antioxidants. OBJECTIVES: This study identified the typical dietary intakes and the major food group contributors of the antioxidants beta-carotene, vitamin C, and vitamin E by smoking status. DESIGN: The 1994-1996 Continuing Survey of Food Intakes by Individuals (CSFII) provided the current sample (n = 6749), who were categorized as non- (n = 3231), former (n = 1684), and current (n = 1834) smokers. In the CSFII, individuals' food intakes were estimated with two 24-h dietary recalls. Data were analyzed by using a chi-square test with a simultaneous Fisher's z test, analysis of variance with Scheffe's test, multivariate analysis of covariance, and analysis of covariance with Bonferroni adjustment for multiple comparisons. RESULTS: The sample consisted of 3707 men and 3042 women. Current smokers tended to be younger with less education and lower incomes than nonsmokers and former smokers. The average body mass index (in kg/m(2)) of current smokers was 25.8, the lowest of the 3 groups. Current smokers had the lowest dietary antioxidant intake. Fatty foods such as luncheon meats, condiments and salad dressings, and ground beef contributed more to the antioxidant intakes of current smokers than to those of the other 2 groups, whereas fruit and vegetables contributed less. Current smokers consumed the fewest numbers of servings of all nutrient-bearing groups in the food guide pyramid, except the meat group. CONCLUSION: Future interventions should target the clustering of cigarette smoking and other unhealthy lifestyle habits, eg, an imprudent diet. (+info)
The bioavailability of beta-carotene in stir- or deep-fried vegetables in men determined by measuring the serum response to a single ingestion.
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To evaluate the bioavailability of beta-carotene from plant foods, the serum beta-carotene response to a single ingestion of various beta-carotene sources was determined in 10 healthy men. Tested beta-carotene sources included stir-fried shredded carrot, stir-fried water convolvulus leaves, deep-fried sweet potato ball, purified beta-carotene in a capsule (beadlets) and beadlets with beta-carotene free oriental radish (beadlets + radish). The maximal change in serum beta-carotene concentration occurred at 24 or 32 h post ingestion. This response to beadlets was significantly higher than that to the other four tested beta-carotene sources (P < 0.05). The maximal serum response to beadlets + radish was also significantly higher than that to the three food beta-carotene sources (P < 0.05). The maximal serum response to sweet potato was significantly higher than that to water convolvulus leaves (P < 0. 05). The bioavailability relative to beta-carotene beadlets was calculated by dividing the maximal change in serum concentration to each test meal of each subject by his own serum maximal change in response to beadlets. Accordingly, the bioavailability was 65% for beadlets + radish, 33% for carrots, 26% for water convolvulus leaves and 37% for sweet potatoes. Concurrent ingestion of oriental radish reduced the bioavailability of beadlets to two-thirds of its original value, which partially accounted for the difference between the bioavailability of beadlets and natural foods. The relative bioavailability of beta-carotene from stir-fried and deep-fried vegetables was about one-third to one-fourth that of the purified beta-carotene beadlets. These bioavailabilities are higher than previously reported values. (+info)
Auxin metabolism in the root apical meristem.
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Within the root meristem of flowering plants is a group of mitotically inactive cells designated the quiescent center (QC). Recent work links the quiescent state to high levels of the growth regulator auxin that accumulates in the QC via polar transport. This in turn results in elevated levels of the enzyme ascorbic acid oxidase (AAO), resulting in a reduction of ascorbic acid (AA) within the QC and mitotic quiescence. We present evidence for additional interactions between auxin, AAO, and AA, and report that, in vitro, AAO oxidatively decarboxylates auxin, suggesting a mechanism for regulating auxin levels within the QC. We also report that oxidative decarboxylation occurs at the root tip and that an intact root cap must be present for this metabolic event to occur. Finally, we consider how interaction between auxin and AAO may influence root development by regulating the formation of the QC. (+info)
Haematocin, a new antifungal diketopiperazine produced by Nectria haematococca Berk. et Br. (880701a-1) causing nectria blight disease on ornamental plants.
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A new antifungal diketopiperazine named haematocin was isolated from the culture broth of Nectria haematococca Berk. et Br. (880701a-1) causing blight disease on ornamental plants, Phalaenopsis spp. and Doritanopsis spp. Its structure was established by spectroscopic methods. Haematocin inhibited the germ-tube elongation and spore-germination of Pyricularia oryzae at the ED50 values of 30 microg/ml and 160 microg/ml, respectively. (+info)
Carbohydrates, dietary fiber, and incident type 2 diabetes in older women.
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BACKGROUND: Dietary carbohydrates may influence the development of type 2 (non-insulin-dependent) diabetes, for example, through effects on blood glucose and insulin concentrations. OBJECTIVE: We examined the relations of baseline intake of carbohydrates, dietary fiber, dietary magnesium, and carbohydrate-rich foods and the glycemic index with incidence of diabetes. DESIGN: This was a prospective cohort study of 35988 older Iowa women initially free of diabetes. During 6 y of follow-up, 1141 incident cases of diabetes were reported. RESULTS: Total grain, whole-grain, total dietary fiber, cereal fiber, and dietary magnesium intakes showed strong inverse associations with incidence of diabetes after adjustment for potential nondietary confounding variables. Multivariate-adjusted relative risks of diabetes were 1.0, 0.99, 0.98, 0.92, and 0.79 (P for trend: 0.0089) across quintiles of whole-grain intake; 1.0, 1.09, 1.00, 0.94, and 0.78 (P for trend: 0.005) across quintiles of total dietary fiber intake; and 1.0, 0.81, 0.82, 0.81, and 0.67 (P for trend: 0.0003) across quintiles of dietary magnesium intake. Intakes of total carbohydrates, refined grains, fruit and vegetables, and soluble fiber and the glycemic index were unrelated to diabetes risk. CONCLUSION: These data support a protective role for grains (particularly whole grains), cereal fiber, and dietary magnesium in the development of diabetes in older women. (+info)
Mediterranean diet and age with respect to overall survival in institutionalized, nonsmoking elderly people.
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BACKGROUND: In studies from Italy and Greece, a Mediterranean dietary pattern was shown to favorably affect life expectancy in the elderly population. This pattern is thought to reduce the risk of cancer in addition to being cardioprotective. OBJECTIVE: The objective of this study was to evaluate the interactive effects of the Mediterranean diet and age with respect to survival after controlling for several other variables that could be considered as confounders: age, sex, body mass index, albumin concentration, physical activity, self-assessment of health, and dieting in response to chronic conditions. DESIGN: This was a cohort study involving 161 nonsmoking elderly subjects (74 subjects aged <80 y and 87 subjects aged > or =80 y) living in Spain. The subjects were followed up for > or =9 y. Diet was assessed with a semiquantitative food-frequency questionnaire. RESULTS: A diet score based on 8 characteristics of the traditional diet in the Mediterranean region was associated with a significant reduction in overall mortality in elderly subjects aged <80 y but not in subjects aged > or =80 y. A unit increase in the diet score predicted a 31% reduction in mortality in subjects aged <80 y (95% CI: 7%, 57%). CONCLUSION: Efforts to promote adherence to the Mediterranean dietary pattern appear to be worthwhile in persons aged <80 y, in whom the diet predicts survival, but we do not have any available evidence that such a diet benefits subjects aged > or =80 y. (+info)