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71.

Purpose

Consumption of phytosterols is a nutritional strategy to reduce cholesterol absorption, but the efficacy of various phytosterol intake modalities remains uncertain. The main objective was to investigate the effects of phytosterol esters (PE) provided either as a spread (dispersed in fat) during a mixed meal or as a minidrink (micro-dispersed in liquid form) after a meal.

Methods

In a randomized, single-blinded crossover design, 12 healthy intubated volunteers tested three different liquid meal sequences with and without PE. The liquid meal (500 mL, Fortisip) contained an oral dose (80 mg) of deuterium-enriched cholesterol (D7C). The intubation was stopped at 240 min, and the fate of sterols was determined in the different phases of duodenal content samples as function of time. A second solid fat-containing meal without sterols was consumed at 270 min. D7C was quantified in chylomicrons and plasma for 8 h. The conditions tested were as follows: (1) no PE added (control), (2) PE in a spread added into a liquid meal (PE-spread meal) and (3) PE given 30 min after a liquid meal as 100-g yoghurt drink (PE-minidrink meal).

Results

Addition of PE decreased the incorporation of cholesterol into the duodenum aqueous phase including micelles. PE added as a spread or as a minidrink significantly and comparably lowered meal cholesterol occurrence in chylomicrons (?40 % for PE-spread and ?54 % for PE-minidrink, p < 0.0001) compared with the control meal.

Conclusions

PE either dispersed in fat during a meal or micro-dispersed in a liquid form after a meal resulted in a markedly reduced occurrence of meal-derived cholesterol in the circulation at a comparable extent.  相似文献   
72.
BACKGROUND: The results of previous studies suggest that de novo lipogenesis may play an important role in the etiology of obesity, particularly during overconsumption of different carbohydrates. OBJECTIVE: We hypothesized that de novo lipogenesis would increase during overfeeding, would vary depending on the type of carbohydrate consumed, and would be greater in obese than in lean women. DESIGN: De novo lipogenesis was measured during 96 h of overfeeding by 50% with either sucrose or glucose and during an energy balance treatment (control) in 8 lean and 5 obese women. De novo lipogenesis was determined by measuring the amount of deuterium incorporation into plasma triacylglycerols. Fat and carbohydrate balance were measured simultaneously by continuous whole-body calorimetry. RESULTS: De novo lipogenesis did not differ significantly between lean and obese subjects, except with the control treatment, for which de novo lipogenesis was greater in the obese subjects. De novo lipogenesis was 2- to 3-fold higher after overfeeding by 50% than after the control treatment in all subjects. The type of carbohydrate overfeeding (sucrose or glucose) had no significant effect on de novo lipogenesis in either subject group. Estimated amounts of absolute VLDL production ranged from a minimum of 2 g/d (control) to a maximum of 10 g/d after overfeeding. This compares with a mean fat balance of approximately 275 g after 96 h of overfeeding. Individual subjects showed characteristic amounts of de novo lipogenesis, suggesting constitutive (possibly genetic) differences. CONCLUSION: De novo lipogenesis increases after overfeeding with glucose and sucrose to the same extent in lean and obese women but does not contribute greatly to total fat balance.  相似文献   
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Improved survival rates for extreme prematurity have been accompanied by an increase in the incidence of bronchopulmonary dysplasia (BPD). The objective of this study was to assess factors associated with long-term nutritional and pulmonary function outcomes. The study was a cross-sectional study of 52 children who had been born prematurely, had experienced BPD, and were 4-8 y old at the time of the study. Undernutrition was defined as a Z score for weight-for-height of <-2 SD. Body composition and lung function were evaluated. Resting energy expenditure (REE) was measured using indirect calorimetry. Stepwise logistic regression was used to test for factors associated with undernutrition and pulmonary function. Eighteen children (35%) with BPD, predominantly girls, were undernourished. Undernutrition occurred within the first months of life and was associated with high REE. Multivariate analysis showed that factors significantly associated with undernutrition were female sex and undernutrition at age 2 y. Thirty-one children (60%) had abnormal lung function tests. Multivariate analysis showed that undernutrition at age 2 y was the only factor associated with the risk of developing distension of the airways. Nutritional status at age 2 y in children who had BPD in infancy influences nutritional and pulmonary outcomes in childhood.  相似文献   
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77.
Ataxia-telangiectasia (AT) is an autosomal recessive inherited disease caused by mutational inactivation of the ATM gene. It is a multisystemic disease, characterized by progressive neurological dysfunction, especially in the cerebellum, oculo-cutaneous telangiectasia, immunodeficiency, recurrent sino-pulmonary infections and high incidence of neoplasms. The responsible gene, ATM, encodes a large protein that belongs to a family of protein kinases with a phosphatidylinositol 3-kinase (Pi3K) domain. ATM is a key regulator of cell cycle checkpoints that causes DNA repair or apoptosis. Several studies report ATM function in target cells (such as neurons, fibroblast, endothelium, germ cells, lymphocytes). The pleiotropic phenotypes of AT reflect the multifaceted activities of ATM protein. In nucleus (lymphocytes, fibroblasts, germ cells) ATM is involved in regulation of cell-cycle checkpoints; in cytoplasm ATM regulates redox state (neurons).  相似文献   
78.
A 61-year-old woman, suffering from classic seropositive rheumatoid arthritis with rheumatoid nodule histologically documented, developed temporal arteritis. HLA-DR typing revealed the presence of DR3 and DR4 antigens. The findings from previous studies support the association of HLA-DR antigens, giant cell arteritis-polymyalgia rheumatica and rheumatoid arthritis, and suggest the participation of a common immunogenetic mechanism in their pathogenesis.  相似文献   
79.
The effect of rokitamycin on human polymorphonuclear leukocyte (PMNL) chemotaxis was studied in vitro and in vivo. It was found that rokitamycin in vitro at a concentration of 20 micrograms/ml caused a diminution of PMNL migration, while at lower concentrations no significant effects on migration was observed. In in-vivo studies before and after the ingestion of rokitamycin by six healthy individuals, no change on PMNL chemotaxis was found.  相似文献   
80.
AIMS: To compare glycaemic control, occurrence of acute complications, and diabetes-specific quality of life in Type 1 diabetic patients (on intensified conventional insulin treatment (ICT)) before and after initiation of CSII. METHODS: One hundred and three patients (58 women) started CSII between October 1995 and April 1999 in our department. The indication for CSII was optimization of metabolic control and improvement of flexibility of life style (OF group) in 60 patients (58%), and prevention of severe hypoglycaemia (HY group) in 43 patients. Mean age at initiation of CSII was 33 +/- 11 years (OF 33 +/- 10, HY 33 +/- 11 (mean +/- sd)), diabetes duration 18 +/- 9 years (OF 16 +/- 9, HY 20 +/- 9). Three patients stopped CSII, mean duration of CSII of the remaining 100 patients was 1.8 +/- 1.2 years. The occurrence of hypoglycaemia, ketoacidosis and skin abscesses was assessed retrospectively for the 12 months before starting CSII, and recorded continuously during CSII. Quality of life was assessed with a validated, diabetes-specific questionnaire before and after CSII in 50 patients. RESULTS: The incidence of serious hypoglycaemia (any external help) was reduced from 1.23 (OF 0.0; HY 2.93) during ICT to 0.29 cases/patient per year (OF 0.09; HY 0.55) during CSII. The incidence of severe hypoglycaemia (SH) (treated with i.v. glucose or glucagon injection) fell from 0.70 (OF 0.0; SH 1.67) during ICT to 0.06 cases/patient per year (OF 0.02; HY 0.12) during CSII. HbA1c improved from 7.7 +/- 1.1% to 7.2 +/- 1.0% (P < 0.001) (OF 7.8% vs. 7.2%; HY 7.6% vs. 7.2%). During CSII the incidence of abscesses was 0.11 and of ketoacidosis 0.01 cases/patient per year. Quality of life assessments showed significant improvement in all parameters during CSII. CONCLUSIONS: In our cohort of Type 1 diabetic patients, we observed a substantial decrease of hypoglycaemia along with a significant fall of HbA1c. Quality of life on CSII was improved when compared with ICT.  相似文献   
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