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461.
OBJECTIVE: To evaluate the impact of a low-cost nutritional intervention in changing the lifestyle of adults. DESIGN: Randomised clinical trial. SETTING: Primary health-care centre in S?o José do Rio Preto, S?o Paulo State, Brazil. SUBJECTS: We randomly assigned 104 adults (83 women and 21 men aged 30-65 years, body mass index 24-35 kg m(-2), non-diabetic) into two groups: nutrition counselling and control. Each subject in the intervention group received three individualised nutritional counselling sessions during the first 6 months aimed at increasing intakes of fruits, vegetables and olive oil, reducing saturated fat and improving physical activity. Body composition, biochemical indicators and lifestyle were assessed at baseline and at 6 months and 1 year in both groups. RESULTS: After 6 months of follow-up, body weight, waist circumference, diastolic blood pressure, fasting blood glucose, total and low-density lipoprotein cholesterol, total and saturated fat, and dietary energy and cholesterol levels showed a more significant decrease among subjects in the intervention group than in the control group (P < 0.05). Moreover, the intervention group showed significantly greater improvement in each intervention goal, such as reduced intake of saturated fat and increased intakes of fruits, vegetables, fibre and olive oil (P < 0.05). After 12 months of follow-up, most of the outcomes were maintained. CONCLUSIONS: The low-cost nutritional intervention programme improved serum lipids profile and weight control, and appeared to be feasible for use at a primary health-care centre in a developing country.  相似文献   
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This study was designed to develop efficient analytical tools for the difficult HPLC-DAD-MS identification of hydrolyzable tannins in natural tissue extracts. Throughout the study of the spectroscopic characteristics of properly synthesized stereodefined standards, it was observed that the UV-vis spectra of compounds with the m-depsidic link showed a characteristic shoulder at 300 nm, consistent with the simple glucogalloyl esters, whereas compounds with the hexahydroxydiphenoyl (HHDP) unit gave a diagnostic fragmentation pattern, caused by a spontaneous lactonization in the mass spectrometer. These observations were confirmed by HPLC-DAD-MS analyses of tannic acid and raspberry extracts, which are rich in hydrolyzable tannins with the m-depsidic link and the HHDP unit, respectively.  相似文献   
465.
To characterize potatoes according to their geographic origin and variety, 10 mineral and trace elements (Mg, Cr, Mn, Fe, Ni, Cu, Zn, Sr, Cd, and Ba) were determined in Italian potato samples. The data collected were successively elaborated using statistical techniques, namely, linear discriminant analysis (LDA). LDA was able to classify and discriminate the potatoes from Fucino both from those of other areas of Italy and from those of the four provinces of Abruzzo. A net separation between the Fucino potatoes and those of the other areas of Abruzzo was observed. LDA discriminated also the three potato varieties cultivated in the Fucino basin. The presence of these 10 mineral and trace elements was a good means for establishing the geographical place of origin of Fucino potatoes.  相似文献   
466.
Seed coats and cotyledons from 25 Brazilian and 3 Peruvian bean cultivars were investigated in relation to their phenolic profiles and antioxidant capacity. Condensed tannins, anthocyanins, and flavonols such as kaempferol and quercetin glycosides were mostly found in seed coats. Cotyledons were rich in phenolic acids, such as ferulic, sinapic, chlorogenic, and other hydroxycinnamic acids. In general, the seed coat color pattern and the type of cultivar showed an important influence on the variability of phenolic profiles and levels, respectively. Total phenolics and antioxidant capacity assessed by the DPPH method were higher in seed coats than in cotyledons. The antioxidant capacity had a significant correlation with condensed tannins for all samples and with total anthocyanins in black and red seed coats, whereas in cotyledons, it was more related to the total phenolic content.  相似文献   
467.
Thirteen sulfur compounds (boiling points from 35 to 231 degrees C), usually considered as possible off-flavoring volatiles, were quantified by a concurrent headspace-solid phase microextraction method coupled with gas chromatography-mass spectrometry (HS-SPME/GC-MS) on 80 not off-flavoring wines of four varieties (Merlot, Marzemino, and Teroldego as red wines and Chardonnay as a white one) and of five vintages produced in the North Italian Trentino region. The results of the research, the first Italian data-bank per variety on such volatiles, allow us to make a comparison with the data of other winegrowing areas, to investigate the aging effect on the considered volatiles, and, finally, to try a variety discrimination using statistical procedures. Dimethyl sulfide, 3-(methylthio)-1-propanol, diethyl sulfide, and diethyl disulfide were found to increase with time whereas 2-mercaptoethanol and ethylmercaptan showed a decreasing trend. Furthermore, the concentration of several compounds was found to be dependent on the variety. For instance, sulfide, disulfides, benzothiazole, and thioalcohols are at higher levels in Merlot wines, whereas thiols and thioacetates are more abundant in Marzemino and Teroldego wines. Chardonnay products, well apart from the other wines, are the poorest in 3-(methylthio)-1-propanol and rather rich in dimethyl disulfide and in diethyl disulfide, mostly in the aged wines. Applying the principal component analysis to the data, it was possible to demonstrate that Chardonnay and Merlot wines are well-discriminated from the Italian native varietal wines, which on their turn are only partially distinguishable among them. A contribution of these compounds to the variety characteristics of wine is reasonable.  相似文献   
468.
OBJECTIVES: To assess vitamin A supplementation (VAS) coverage of children aged 6-59 months and the factors that favour or limit this coverage during the National Nutrition Weeks in Mali. DESIGN: Cross-sectional study. Interviews about demographic factors and children's adherence to the vitamin A capsule distribution programme were conducted. Professionals' knowledge of vitamin A and various aspects related to the supplementation strategy were assessed. SETTING: Five regions out of the eight regions in the country, in addition to Bamako District. Three rural communes were selected in three regions to represent rural areas. SUBJECTS: Parents or caregivers of children under 5 years of age, health agents who participated in the weeks, and community and administrative leaders. RESULTS: At least 80% of the children received the supplement. More 'traditional' communication channels (town criers, friends and family members) appeared to be more effective in reaching the target groups than modern methods, i.e. radio and television. Mothers' possession of a radio (Pearson chi2 = 5.03; P = 0.025) and fathers' education (Pearson chi2 = 19.02; P < 0.001), possession of a radio (Pearson chi2 = 8.93; P = 0.003) and listening to it (Pearson chi2 = 7.62; P = 0.006) all appeared to be statistically and significantly associated with children's coverage. In multivariate logistic regression analysis, only the study site (urban/rural) (P = 0.004), 'traditional channels' (P = 0.02) and fathers' education (P = 0.04) were significantly associated with children's coverage. Knowledge about VAS was high among community and administrative leaders, and health professionals. The planning and implementation of activities at the district level were found to be good in general. CONCLUSION: National Nutrition Weeks provide a successful example of a periodic VAS strategy with high coverage among children aged 6-59 months in Mali. Campaigns aimed at informing and sensitising populations during the Nutrition Weeks should also target children's fathers.  相似文献   
469.
The knowledge of the contents and profile of isoflavones present in soy protein ingredients, as well as the effect of industrial processing, is important for the development of functional foods rich in these compounds. The results obtained here showed that the total isoflavone content varied significantly among products. For defatted and whole soy flours the total isoflavone content ranged from 120 to 340 mg/100 g, for soy protein isolates from 88 to 164 mg/100 g, and for commercial textured soy proteins, from 66 to 183 mg/100 g (wet basis, expressed as aglycones). The highest isoflavone content was found for soy hypocotyl flours, from 542 to 851 mg/100 g. Compared to hypocotyl and whole and defatted flours, soy ingredients presented a decrease of malonylglycosides and deesterified β-glycosides with a significant increase in the percentage of aglycones, mainly for soy fibers (65–76%). While defatting was shown to cause isoflavone concentration without altering conjugation, extrusion process caused destruction of isoflavones and a significant increase in the amount of acetylglycosides, but this effect was less intense for the concentrates. From the results obtained it can be concluded that differences in isoflavone concentration and profile may be related to oscillations in the isoflavone content present in the raw material and to the type of processing.  相似文献   
470.

Background, aim, and scope  

Diffuse soil contamination has often been neglected in scientific literature, as most studies focus on contaminants from point-sources (either of industrial or agricultural origin). However, soil pollution from diffuse sources is recognized as one of the major soil threats by the EU Soil Thematic Strategy. In fact, some pollutants are nowadays ubiquitarious in the soil system, and they have to be considered for the implementation of environmental legislation, the definition of clean-up values in remediation activities and, more generally, for a sustainable management of rural areas. In the literature large scale studies on diffuse contamination are few and scattered and often do not consider a wide range of contaminants, the effect of land use, the vertical variability and the potential natural contribution. Aim of this work was to provide an overview of the diffuse soil contamination on a regional scale for a large set of contaminants. Soil inorganic (Cd, Cr, Ni, Pb, Cu, Zn) and organic contaminants (polychlorinated dibenzo-p-dioxins(PCDD), polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) as well as other soil general parameters were investigated on a 18 × 18 km grid covering a whole Italian region heavily industrialized and intensively cultivated. Soils were sampled at different depths both for natural–undisturbed soil and for agricultural–plow soil. Differences in the trends of investigated contaminants, as a consequence of land use, vertical variability, natural or geogenic origin, relationships among contaminants, and with main soil properties, were explored by means of enrichment factors, bi- and multi-variate statistics.  相似文献   
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