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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.cell.2009.02.041 Byline: C. Mark Fletcher (1), Michael J. Coyne (1), Otto F. Villa (2), Maria Chatzidaki-Livanis (1), Laurie E. Comstock (1) Keywords: MICROBIO Abstract: The Bacteroides are a numerically dominant genus of the human intestinal microbiota. These organisms harbor a rare bacterial pathway for incorporation of exogenous fucose into capsular polysaccharides and glycoproteins. The infrequency of glycoprotein synthesis by bacteria prompted a more detailed analysis of this process. Here, we demonstrate that Bacteroides fragilis has a general O-glycosylation system. The proteins targeted for glycosylation include those predicted to be involved in protein folding, protein-protein interactions, peptide degradation as well as surface lipoproteins. Protein glycosylation is central to the physiology of B. fragilis and is necessary for the organism to competitively colonize the mammalian intestine. We provide evidence that general O-glycosylation systems are conserved among intestinal Bacteroides species and likely contribute to the predominance of Bacteroides in the human intestine. Author Affiliation: (1) Channing Laboratory, Brigham & Women's Hospital, Harvard Medical School, 181 Longwood Avenue, Boston, MA 02115, USA (2) Pulmonary Critical Care and Sleep Division, Department of Medicine, Mount Sinai School of Medicine, 1468 Madison Avenue, New York, NY 10029, USA Article History: Received 8 October 2008; Revised 31 December 2008; Accepted 19 February 2009 Article Note: (miscellaneous) Published: April 16, 2009

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.anbehav.2004.05.018 Byline: Kevin J. McGraw, Geoffrey E. Hill, Robert S. Parker Abstract: Many sexually selected traits are thought to be costly to produce, which ensures that they communicate information honestly to conspecifics. Carotenoid pigmentation is classically considered as a costly sexual signal in many fish and birds. It is often argued that carotenoid colours are 'condition dependent', with an individual's nutritional or health state directly determining trait expression. However, few studies have investigated precisely how a compromised nutritional state affects an animal's capacity to develop these sexually attractive colours. Here, we studied the effect of food restriction on the ability of male American goldfinches to physiologically process carotenoids during the period of feather growth. We used high-performance liquid-chromatography to determine the types and amounts of carotenoids circulating in blood during moult as well as in newly grown colourful feathers. We show that nutritional deprivation affects the degree to which male goldfinches transport carotenoids through the bloodstream. Food-restricted males circulated significantly less blood carotenoids than controls. They also incorporated less carotenoids into feathers and grew less colourful plumage, but the decrease in plumage carotenoids did not significantly exceed the depressed amounts already present in blood. These results suggest that the means by which these yellow-coloured passerines either extract carotenoids from food (e.g. via lipoidal micelles) or transport them through blood (e.g. via lipoproteins) are more sensitive to changes in nutritional/energy state than are the mechanisms for metabolizing dietary pigments or depositing metabolites into feathers. Author Affiliation: (*) Department of Neurobiology and Behavior, Cornell University, U.S.A. (a ) Department of Biological Sciences, Auburn University,U.S.A. (a ) Division of Nutritional Sciences, Cornell University, U.S.A. Article History: Received 26 January 2004; Revised 7 April 2004; Accepted 13 May 2004 Article Note: (miscellaneous) MS. number: A9803R

Background: Postprandial lipid metabolism in humans has deserved much attention during the last two decades. Although fasting lipid and lipoprotein parameters reflect body homeostasis to some extent, the transient lipid and lipoprotein accumulation that occurs in the circulation after a fat-containing meal highlights the individual capacity to handle an acute fat input. An exacerbated postprandial accumulation of triglyceride-rich lipoproteins in the circulation has been associated with an increased cardiovascular risk. Methods: The important number of studies published in this field raises the question of the methodology used for such postprandial studies, as reviewed. Results: Based on our experiences, the present review reports and discuss the numerous methodological issues involved to serve as a basis for further works. These aspects include aims of the postprandial tests, size and nutrient composition of the test meals and background diets, pre-test conditions, characteristics of subjects involved, timing of sampling, suitable markers of postprandial lipid metabolism and calculations. Conclusion: In conclusion, we stress the need for standardization of postprandial tests. European Journal of Clinical Nutrition (2007) 61, 1145-1161; doi: 10.1038/sj.ejcn.1602749; published online 25 April 2007 Keywords: nutrition, human, meals, gene polymorphisms, cardiovascular disease, Author(s): D Lairon [1, 2, 3]; J Lopez-Miranda [4]; C Williams [5] Introduction Postprandial lipid metabolism: characteristics and importance Unlike circulating carbohydrates that normally show only transient elevations (as glucose) [...]

Research has been conducted on ATP-binding cassete transporter A1(ABCA1). The authors have investigated the changes in lipoprotein fractions in Abca1-deficient mice, and the mechanisms responsible for HDL low levels in the absence of Abca1.

We studied the impact of substituting ethanol for dietary carbohydrate, in high- and low-fat, diets, on plasma lipids and lipoprotein concentrations. During a 12-wk, weight maintaining, controlled feeding study, women consumed only food and beverage provided by the Human Studies Facility of the USDA Beltsville Human Nutrition Research Center. Twenty-six women (age 41-59 y) consumed either a high-fat diet (38% of energy from fat) or a low-fat diet (18% of energy from fat) for 12 wk. The 12-wk feeding period was divided into two 6-wk periods in a cross-over design during which either ethanol or carbohydrate was added to the diet (5% of total daily energy intake). When the women consuming the high-fat diet had ethanol added to their diet, they had 6% lower plasma cholesterol (P = 0.003), 11% lower LDL cholesterol (P = 0.001) and 3% higher HDL cholesterol (P = 0.06) than when they had an equal amount (% energy) of carbohydrate added to their diet. The greater HDL cholesterol concentration was due to a 21% greater the (HDL.sub.2) subfraction (P = 0.001). The ratio of LDL to HDL cholesterol was 14% lower. No significant differences existed in plasma lipids in women consuming the low-fat diet between the periods in which they had ethanol or carbohydrate added to their diet. This study suggests that the decreases in cardiovascular disease risk factors typically seen with moderate alcohol consumption may not be evident in individuals consuming a diet low in fat. Therefore changes in the risk factors associated with a low-fat diet and moderate alcohol consumption do not appear to be additive. J. Nutr. 129: 1713-1717, 1999. KEY WORDS: * blood lipids * plasma cholesterol * ethanol consumption * dietary fat * humans