Outcome-Dependent Sampling: An Efficient Sampling and Inference Procedure for Studies With a Continuous Outcome

To characterize the relation between an exposure and a continuous outcome, the sampling of subjects can be done much as it is in a case-control study, such that the sample is enriched with subjects who are especially informative. In an outcome dependent sampling (ODS) design, observations made on a judiciously chosen subset of the base population can provide nearly the same statistical efficiency as observing the entire base population. Reaping the benefits of such sampling, however, requires use of an analysis that accounts for the ODS design. In this report, the authors examined the statistical efficiency of a plain random sample analyzed with standard methods, compared with that of data collected with an ODS design and analyzed by either of two appropriate methods. In addition, three real datasets were analyzed using an ODS approach. The results demonstrate the improved statistical efficiency obtained by using an ODS approach and its applicability in a wide range of settings. An ODS design, coupled with an appropriate analysis, can offer a cost-efficient approach to studying the determinants of a continuous outcome

Low serum folate concentrations are associated with an excess incidence of acute coronary events: the Kuopio Ischaemic Heart Disease Risk Factor Study

http://deepblue.lib.umich.edu/bitstream/2027.42/51489/1/Voutilainen S, Low Serum Folate Concentrations, 2000.pd

Structure and characterization of a novel chicken biotin-binding protein A (BBP-A)

BACKGROUND: The chicken genome contains a BBP-A gene showing similar characteristics to avidin family genes. In a previous study we reported that the BBP-A gene may encode a biotin-binding protein due to the high sequence similarity with chicken avidin, especially at regions encoding residues known to be located at the ligand-binding site of avidin. RESULTS: Here, we expand the repertoire of known macromolecular biotin binders by reporting a novel biotin-binding protein A (BBP-A) from chicken. The BBP-A recombinant protein was expressed using two different expression systems and purified with affinity chromatography, biochemically characterized and two X-ray structures were solved – in complex with D-biotin (BTN) and in complex with D-biotin D-sulfoxide (BSO). The BBP-A protein binds free biotin with high, "streptavidin-like" affinity (K(d )~ 10(-13 )M), which is about 50 times lower than that of chicken avidin. Surprisingly, the affinity of BBP-A for BSO is even higher than the affinity for BTN. Furthermore, the solved structures of the BBP-A – BTN and BBP-A – BSO complexes, which share the fold with the members of the avidin and lipocalin protein families, are extremely similar to each other. CONCLUSION: BBP-A is an avidin-like protein having a β-barrel fold and high affinity towards BTN. However, BBP-A differs from the other known members of the avidin protein family in thermal stability and immunological properties. BBP-A also has a unique ligand-binding property, the ability to bind BTN and BSO at comparable affinities. BBP-A may have use as a novel material in, e.g. modern bio(nano)technological applications

Structure and characterization of a novel chicken biotin-binding protein A (BBP-A)

Background. The chicken genome contains a BBP-A gene showing similar characteristics to avidin family genes. In a previous study we reported that the BBP-A gene may encode a biotin-binding protein due to the high sequence similarity with chicken avidin, especially at regions encoding residues known to be located at the ligand-binding site of avidin. Results. Here, we expand the repertoire of known macromolecular biotin binders by reporting a novel biotin-binding protein A (BBP-A) from chicken. The BBP-A recombinant protein was expressed using two different expression systems and purified with affinity chromatography, biochemically characterized and two X-ray structures were solved – in complex with D-biotin (BTN) and in complex with D-biotin D-sulfoxide (BSO). The BBP-A protein binds free biotin with high, "streptavidin-like" affinity (Kd ~ 10-¹³ M), which is about 50 times lower than that of chicken avidin. Surprisingly, the affinity of BBP-A for BSO is even higher than the affinity for BTN. Furthermore, the solved structures of the BBP-A – BTN and BBP-A – BSO complexes, which share the fold with the members of the avidin and lipocalin protein families, are extremely similar to each other. Conclusion. BBP-A is an avidin-like protein having a β-barrel fold and high affinity towards BTN. However, BBP-A differs from the other known members of the avidin protein family in thermal stability and immunological properties. BBP-A also has a unique ligand-binding property, the ability to bind BTN and BSO at comparable affinities. BBP-A may have use as a novel material in, e.g. modern bio(nano)technological applications.peerReviewe

Serum homocysteine, folate and risk of stroke: Kuopio Ischaemic Heart Disease Risk Factor (KIHD) Study

http://deepblue.lib.umich.edu/bitstream/2027.42/51490/1/Virtanen JK, Serum Homocysteine, Folate and Risk of Stroke, 2005.pd

FTO genetic variants, dietary intake and body mass index: insights from 177 330 individuals

FTO is the strongest known genetic susceptibility locus for obesity. Experimental studies in animals suggest the potential roles of FTO in regulating food intake. The interactive relation among FTO variants, dietary intake and body mass index (BMI) is complex and results from previous often small-scale studies in humans are highly inconsistent. We performed large-scale analyses based on data from 177 330 adults (154 439 Whites, 5776 African Americans and 17 115 Asians) from 40 studies to examine: (i) the association between the FTO-rs9939609 variant (or a proxy single-nucleotide polymorphism) and total energy and macronutrient intake and (ii) the interaction between the FTO variant and dietary intake on BMI. The minor allele (A-allele) of the FTO-rs9939609 variant was associated with higher BMI in Whites (effect per allele = 0.34 [0.31, 0.37] kg/m2, P = 1.9 × 10−105), and all participants (0.30 [0.30, 0.35] kg/m2, P = 3.6 × 10−107). The BMI-increasing allele of the FTO variant showed a significant association with higher dietary protein intake (effect per allele = 0.08 [0.06, 0.10] %, P = 2.4 × 10−16), and relative weak associations with lower total energy intake (−6.4 [−10.1, −2.6] kcal/day, P = 0.001) and lower dietary carbohydrate intake (−0.07 [−0.11, −0.02] %, P = 0.004). The associations with protein (P = 7.5 × 10−9) and total energy (P = 0.002) were attenuated but remained significant after adjustment for BMI. We did not find significant interactions between the FTO variant and dietary intake of total energy, protein, carbohydrate or fat on BMI. Our findings suggest a positive association between the BMI-increasing allele of FTO variant and higher dietary protein intake and offer insight into potential link between FTO, dietary protein intake and adiposit

Effects of individual dietary counseling as part of a comprehensive geriatric assessment (CGA) on frailty status: A population-based intervention study

AbstractBackground/PurposeIn this study, our aim was to evaluate the effects of individual dietary counseling as part of a comprehensive geriatric assessment (CGA) on frailty status among community-dwelling people aged 75 years or older.MethodsData were obtained from a subpopulation of participants in the population-based Geriatric Multidisciplinary Strategy for the Good Care of the Elderly (GeMS) intervention study in 2004 to 2007. In the present study, the population consisted of 159 persons at risk of malnutrition in the year 2005 in an intervention and a control group. Nutritional status was assessed with the Mini Nutritional Assessment (MNA). Frailty was defined according to the five frailty criteria used in the Cardiovascular Health Study (CHS). Assessment of nutritional status and frailty status was performed at the beginning of the study and at 1-year follow-up.ResultsAt baseline the mean age of the 159 community-dwelling participants with risk of malnutrition was 83 years and 126 (79%) of them were female. The proportions of frail and pre-frail persons were 25% (n = 19) and 61% (n = 47) in the intervention group, and 26% (n = 21) and 61% (n = 50) in the control group. After the 1-year nutritional intervention, compared to the control group, the intervention group tended to have a better outcome of frailty and MNA (OR = 1.89, 95% CI: 1.08–3.54, OR = 2.61, 95% CI: 1.67–5.56, respectively) and was less likely to deteriorate as assessed with MNA (OR = 0.23, 95% CI: 0.14–0.87). In multivariate analysis, change in MNA (OR = 1.12, 95% CI: 1.03–1.31) was associated independently with improved frailty status.ConclusionIt appears that multidisciplinary geriatric assessment including individual dietary counseling has a positive effect on frailty status. More emphasis on good nutrition in the older population might have a preventive effect on the incidence of frailty

Serum lycopene concentrations and carotid atherosclerosis: the Kuopio Ischaemic Heart Disease Risk Factor Study

http://deepblue.lib.umich.edu/bitstream/2027.42/51569/1/Rissanen TH, Serum Lycopene Concentrations and Carotid Atherosclerosis, 2003.pd

Dietary Folate and depressive symptoms are associated in middle-aged Finnish middle-aged men

http://deepblue.lib.umich.edu/bitstream/2027.42/51505/1/Tolmunen T, Dietary Folate and Depressive Symptoms, 2003.pd