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991.
High propionic acid fermentations and mineral accumulation in the cecum of rats adapted to different levels of inulin 总被引:4,自引:0,他引:4
The digestive and metabolic effects of inulin (from chicory) were studied in rats adapted to semipurified diets containing 0, 5, 10 or 20% inulin (wt/wt). Moderate levels of inulin (5-10%) did not significantly affect food intake or body weight gain. Dietary inulin resulted in considerably greater cecal fermentation and a significantly greater intraluminal concentration of propionate (peaking at 58.4 mmol/L). A lower concentration of acetate (42.6 mmol/L) was observed in rats fed 20% inulin. Lactic fermentations were observed in rats fed the 10 or 20% inulin diets. The cecal pool of volatile fatty acids tended to reach a plateau in rats fed diets containing more than 10% inulin (up to 600-700 mumol), but volatile fatty acid absorption was a slightly hyperbolic function of the dietary inulin level. Butyrate absorption was proportionally lower than that of propionate. Inulin-containing diets induced an enlargement of the cecal pool of calcium, phosphate and (to a lesser extent) magnesium. There was also an enhanced absorption of these divalent cations. The cecal pool of bile acids was greater in rats fed inulin, and this oligosaccharide displayed a slight hypocholesterolemic effect, even in rats fed the 5% inulin diet. However, plasma triglycerides were depressed only in rats fed the 20% inulin diet. In conclusion, inulin seems very effective in promoting propionic fermentation and in enhancing the calcium content of the large intestine. However, high levels of inulin (greater than 10%) may affect growth in rats and lead to acidic (pH 5.65) cecal fermentation. 相似文献
992.
P Wolmarans A J Benadé T J Kotze A K Daubitzer M P Marais R Laubscher 《The American journal of clinical nutrition》1991,53(5):1171-1176
The effect of 6 wk of either red meat (RM) or fatty fish (FF) intake on plasma lipid concentrations in 28 free-living volunteers (12 males, 16 females) aged 22-45 y was investigated in this clinical crossover trial. Dietary intake was estimated by 7-d dietary records, and fasting blood samples were analyzed for plasma lipid concentrations. Although energy intake did not differ, protein intake was higher (P less than 0.01) in the FF period than in the RM period. There was also a difference (P less than 0.001) in the ratio of dietary polyunsaturated to saturated fatty acids in the RM (0.45) and FF (0.93) periods. Mean plasma total cholesterol, low-density-lipoprotein cholesterol, very-low-density-lipoprotein (VLDL) cholesterol VLDL-triacylglycerol, and plasma triacylglycerol concentrations were lower (P less than 0.001) in the FF than in the RM period. Positive correlations between animal-protein intake and plasma lipoproteins were observed. Atherogenic plasma lipoprotein concentrations were lower when FF was substituted for RM. 相似文献
993.
S D Phinney A B Tang C R Waggoner R G Tezanos-Pinto P A Davis 《The American journal of clinical nutrition》1991,53(6):1404-1410
Serum lipoproteins, body composition, and adipose cholesterol contents of six obese women were studied during and after major weight loss by very-low-calorie diets (VLCDs). Subjects started at 168 +/- 11% of ideal body weight, lost 30.3 +/- 3.7 kg in 5-7 mo, followed by 2+ mo in weight maintenance. Serum cholesterol fell from a prediet (baseline) value of 5.49 +/- 0.32 to 3.62 +/- 0.31 mmol/L (P less than 0.01) after 1-2 mo of VLCDs (nadir), after which it rose to 5.95 +/- 0.36 mmol/L (peak, P less than 0.01 compared with nadir and baseline) as weight loss continued. With weight maintenance, serum cholesterol fell to 4.92 +/- 0.34 mmol/L (P less than 0.05 compared with peak). Adipose cholesterol content did not change in peripheral (arm and leg) biopsy sites but rose significantly in abdominal adipose tissue with weight loss. We conclude that major weight loss was associated with a late rise in serum cholesterol, possibly from mobilization of adipose cholesterol stores, which resolved when weight loss ceased. 相似文献
994.
A M Schols E W Fredrix P B Soeters K R Westerterp E F Wouters 《The American journal of clinical nutrition》1991,54(6):983-987
Resting energy expenditure (REE) was measured in 68 patients with stable chronic obstructive pulmonary disease (COPD) and in 34 weight-stable, age-matched (65 +/- 8 y; means +/- SD) healthy control subjects. Fat-free mass (FFM) determined by bioelectrical resistance explained 84% of the variation in REE in the control group but only 34% in the COPD patients. REE could not reliably be predicted from regression equations either developed in healthy subjects or in COPD patients. REE adjusted for FFM was significantly higher (P less than 0.05) in weight-losing (n = 34) than in weight-stable (n = 34) patients (6851 +/- 781 and 6495 +/- 650 kJ/d, respectively). Pulmonary function was more compromised in weight-losing patients. Adjusted REE in weight-stable patients was significantly higher (P less than 0.01) than in the healthy control group (6131 +/- 405 kJ/d). In patients with COPD, factors in addition to FFM are important determinants of REE. A disease-related increase in REE develops, which may contribute to weight loss in COPD in combination with a lack of an adaptive response to undernutrition in weight-losing patients. 相似文献
995.
Plasma lecithin-cholesterol acyltransferase (LCAT) activity, lipoprotein composition, and lipoprotein concentrations were measured in 21 children with kwashiorkor before (day 1), during (day 10), and after treatment (day 30). Day 1 LCAT activity (78.2 mumol.L-1.h-1) was decreased with respect to day 10 (139.2 mumol.L-1.h-1, P less than 0.001) and day 30 (108.0 mumol.L-1.h-1, P = 0.08). Plasma total cholesterol (TC), cholesterol ester (CE), and lipoprotein CEs (VLDL, IDL, LDL, and HDL) were reduced relative to days 10 and 30 (P less than 0.001). Before treatment HDL composition was abnormal. On days 1, 10, and 30, the respective mean HDL-apolipoprotein A-I (apo A-I) concentrations were 23.33, 39.66, and 36.08 mumol/L. LDL-apo B concentrations were 0.40, 0.68, and 0.56 mumol/L (P less than 0.01, days 10 and 30 vs day 1). LDL particles on day 1 were decreased in number, depleted of CE, and laden with triacylglycerol and surface lipids. LCAT activity on day 1 correlated with LDL-CE linoleate (P less than 0.05, r = 0.48). Reduced plasma LCAT activity is an important factor related to abnormalities in lipoprotein composition and concentrations. 相似文献
996.
Nutrition labels in bar graph format deemed most useful for consumer purchase decisions using adaptive conjoint analysis 总被引:1,自引:1,他引:0
C J Geiger B W Wyse C R Parent R G Hansen 《Journal of the American Dietetic Association》1991,91(7):800-807
This study estimated the effects of changing multiple levels and combinations of nutrition information format, load, expression, and order on consumers' perceptions of label usefulness in purchase decisions using adaptive conjoint analysis. A shopping mall intercept survey, which was administered by a marketing research firm, assessed consumer preferences for 12 label alternatives produced on Campbell's soup cans to portray nutrition information realistically; 252 of 258 respondents completed the computer interactive interview. Consumers significantly preferred the bar graph format to the bar graph/nutrient density and traditional label formats. Consumers considered the bar graph/nutrient density format to be as useful as the traditional label format. There was a highly significant difference among the three levels of information load; the most information load was preferred regardless of nutrient importance. Consumers significantly preferred nutrition information stated in absolute numbers and percentages vs in absolute numbers only in traditional, or in percentages only expressions. There was a significant difference between consumer preferences for the two types of information order. The findings indicate that consumers clearly preferred the nutrition label that displayed all nutrient values using a bar graph format, offered the most information load, and expressed nutrient values using both absolute numbers and percentages. Consumers also preferred nutrition information rearranged in an order that grouped nutrients that should be consumed in adequate amounts on the top, calories in the middle, and nutrients that should be consumed in lesser amounts on the bottom of the label. 相似文献
997.
P M de Vries H B Folkers C W de Fijter J van der Meulen M Luitingh-van der Veen C Popp-Snijders L P Oe 《The American journal of clinical nutrition》1991,53(2):469-473
Adipose tissue fatty acid composition, serum lipid profile, and dietary intake of 37 patients on maintenance hemodialysis were studied. In August 1982, 1984, and 1986, analyses were carried out in 15 normotriglyceridemic (NTG) and 22 hypertriglyceridemic (HTG; type IV hyperlipidemia) patients. No correlations were found between dietary intake of polyunsaturated fatty acids (PUFAs), ratio of polyunsaturated to saturated fatty acids (P-S ratio), and carbohydrate content on the one hand and serum lipid concentrations on the other in the two groups. Adipose tissue linolenic acid correlated negatively with serum cholesterol in both groups. Strong correlations were found between dietary intake of PUFAs and adipose tissue linoleic acid content, between PUFAs and the double-bond index, between P-S ratio and adipose tissue linoleic acid content, and between P-S ratio and the double-bond index. No significant differences in dietary intake or adipose tissue fatty acid composition were observed between NTG and HTG patients. Thus, no evidence was found for exogenous dietary influences on serum lipid concentrations. The adipose tissue linoleic acid content did reflect the dietary intake of PUFAs. 相似文献
998.
C Carlier J P Moulia-Pelat J F Ceccon M S Mourey B Ameline M Fall M N'Diaye O Amédée-Manesme 《The American journal of clinical nutrition》1991,53(1):70-73
The purpose of our study was to determine the prevalence of protein-calorie malnutrition (PCM), ocular diseases, and vitamin A deficiency in preschool children selected at random in a rural zone of the groundnut belt of Senegal. The prevalence of PCM was 37.1% (95% CI 33.8-40.2%) according to the Waterlow classification, with a majority of stunting, and prevalence of hypovitaminosis A was estimated to be 11.4% (95% CI 9.3-13.5%) by using impression cytology. Furthermore, 19.4% (95% CI 15.8-22.0%) of the children might be defined at risk of deficiency. The prevalence of Bitot's spots was equal to 0.2% (95% CI 0.03-0.9%). A problem of PCM associated with a health-endangering vitamin A deficiency existed. 相似文献
999.
1000.