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41.
Improving the dietary quality of women and children is essential to reduce all forms of malnutrition. In this study, we assessed seasonal child and maternal dietary diversity and consumption of animal‐source foods (ASF), using 1,236 observations from combined data collected among 167 mother–child dyads in rural Timor‐Leste. We used generalized linear and logistic mixed‐effects models to examine the dietary differentials of mothers and children in two agricultural livelihood zones and across the seasons, as well as to identify household and agroecological characteristics associated with children's dietary quality in relation to their mothers'. We found dietary quality to be marginally better in coastal than in mid‐altitude zones. However, women's diets were strikingly poor, and their intake of ASF was lower than among children. Mothers exhibited preferential allocation patterns of specific ASF, dairy products and eggs, to children. The intake of ASF was predicted by seasonality. Flesh foods and red meat were much more likely to be consumed during the dry season, when cultural ceremonies are often performed. We found a positive and strongly significant association between children's dietary indicators—dietary diversity score, minimum dietary diversity and ASF consumption, and those of their mothers'. Maternal dietary quality and educational attainment, more so than agroecological characteristics, were explanatory factors of children's diet. Our study highlights that addressing the dietary quality of children in Timor‐Leste would benefit from improving women's diets through better access to nutritious foods and to secondary education. 相似文献
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Interference with hepatocellular substrate uptake by 1,1,1-trichloroethane and tetrachloroethylene 总被引:2,自引:0,他引:2
V Kukongviriyapan U Kukongviriyapan N H Stacey 《Toxicology and applied pharmacology》1990,102(1):80-90
The effects of chlorinated aliphatic hydrocarbon solvent exposure on hepatocellular transport of some model substrates have been investigated. Exposure of isolated hepatocytes to 1,1,1-trichloroethane or tetrachloroethylene resulted in suppression of uptake of taurocholate, ouabain, and 2-aminoisobutyric acid but not CdCl2 or 3-O-methyl-D-glucose. The effect was clearly evident at noncytotoxic concentrations, as indicated by the lack of intracellular enzyme leakage and unaltered intracellular K+ ion concentration. Moreover, the ultrastructure of solvent-exposed hepatocytes was similar to that of control cells, except for a reduction in membrane microvilli. The suppression of uptake was reversible provided that sufficient time was allowed for the cells to recover. The mechanism of this inhibition may be associated with energy-linked processes, as uptake of taurocholate, ouabain, and 2-aminoisobutyric acid is energy requiring while uptake of CdCl2 and 3-O-methyl-D-glucose is not. Cellular ATP was reduced in a dose-dependent manner, but a marked depletion occurred only at cytotoxic concentrations. Na(+)-K(+)- and Mg2(+)-ATPase activities in hepatocyte plasma membrane preparations were also inhibited by solvent exposure. The data suggest that 1,1,1-trichloroethane and tetrachloroethylene interfere specifically with energy-dependent hepatic transport functions and that a decrease in ATP levels and/or inhibition of cell membrane ATPases may be the mechanism. 相似文献
44.
Timely follow‐up of positive cancer screening results: A systematic review and recommendations from the PROSPR Consortium 下载免费PDF全文
Chyke A. Doubeni MD MPH Nicole B. Gabler PhD MPH MHA Cosette M. Wheeler PhD Anne Marie McCarthy PhD Philip E. Castle PhD MPH Ethan A. Halm MD MPH Mitchell D. Schnall MD PhD Celette S. Skinner PhD Anna N. A. Tosteson ScD Donald L. Weaver MD Anil Vachani MD Shivan J. Mehta MD MBA Katharine A. Rendle PhD MSW MPH Stacey A. Fedewa PhD Douglas A. Corley MD PhD Katrina Armstrong MD 《CA: a cancer journal for clinicians》2018,68(3):199-216
Timely follow‐up for positive cancer screening results remains suboptimal, and the evidence base to inform decisions on optimizing the timeliness of diagnostic testing is unclear. This systematic review evaluated published studies regarding time to follow‐up after a positive screening for breast, cervical, colorectal, and lung cancers. The quality of available evidence was very low or low across cancers, with potential attenuated or reversed associations from confounding by indication in most studies. Overall, evidence suggested that the risk for poorer cancer outcomes rises with longer wait times that vary within and across cancer types, which supports performing diagnostic testing as soon as feasible after the positive result, but evidence for specific time targets is limited. Within these limitations, we provide our opinion on cancer‐specific recommendations for times to follow‐up and how existing guidelines relate to the current evidence. Thresholds set should consider patient worry, potential for loss to follow‐up with prolonged wait times, and available resources. Research is needed to better guide the timeliness of diagnostic follow‐up, including considerations for patient preferences and existing barriers, while addressing methodological weaknesses. Research is also needed to identify effective interventions for reducing wait times for diagnostic testing, particularly in underserved or low‐resource settings. CA Cancer J Clin 2018;68:199–216 . © 2018 American Cancer Society . 相似文献
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46.
Ying Han Daniel S. Morris Stacey Schubert Duyen Ngo Jane M. Moore 《Preventing chronic disease》2010,7(5)
Introduction
Worksite health promotion and interventions have gained popularity among state agencies. We studied the health behaviors and health characteristics of adults employed in state agencies in Oregon and compared those state employees with the statewide population of employed, insured adults.Methods
We used data from the Oregon Behavioral Risk Factor Surveillance System (BRFSS) and a modified BRFSS survey administered to state employees. State employees were compared with employed, insured BRFSS respondents in total and then separately for men and women.Results
The prevalence of healthy weight was lower among state employees compared with the statewide population of employed, insured adults (29% vs 35%), and the prevalence of obesity was higher (35% vs 26%). State employees were also less likely to meet physical activity recommendations (44% vs 56%). Diabetes prevalence was higher among state employees (7% vs 5%), and self-reported excellent or very good health status was lower (54% vs 64%).Conclusions
State employees differ from the statewide population of employed, insured adults on a number of health behaviors and conditions. These differences suggest obesity prevention and diabetes control as priority areas for state agency worksite interventions. 相似文献47.
Omar Delannoy-Bruno Chandani Desai Juan J. Castillo Garret Couture Ruteja A. Barve Vincent Lombard Bernard Henrissat Jiye Cheng Nathan Han David K. Hayashi Alexandra Meynier Sophie Vinoy Carlito B. Lebrilla Stacey Marion Andrew C. Heath Michael J. Barratt Jeffrey I. Gordon 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(20)
Increases in snack consumption associated with Westernized lifestyles provide an opportunity to introduce nutritious foods into poor diets. We describe two 10-wk-long open label, single group assignment human studies that measured the effects of two snack prototypes containing fiber preparations from two sustainable and scalable sources; the byproducts remaining after isolation of protein from the endosperm of peas and the vesicular pulp remaining after processing oranges for the manufacture of juices. The normal diets of study participants were supplemented with either a pea- or orange fiber-containing snack. We focused our analysis on quantifying the abundances of genes encoding carbohydrate-active enzymes (CAZymes) (glycoside hydrolases and polysaccharide lyases) in the fecal microbiome, mass spectrometric measurements of glycan structures (glycosidic linkages) in feces, plus aptamer-based assessment of levels of 1,300 plasma proteins reflecting a broad range of physiological functions. Computational methods for feature selection identified treatment-discriminatory changes in CAZyme genes that correlated with alterations in levels of fiber-associated glycosidic linkages; these changes in turn correlated with levels of plasma proteins representing diverse biological functions, including transforming growth factor type β/bone morphogenetic protein-mediated fibrosis, vascular endothelial growth factor-related angiogenesis, P38/MAPK-associated immune cell signaling, and obesity-associated hormonal regulators. The approach used represents a way to connect changes in consumer microbiomes produced by specific fiber types with host responses in the context of varying background diets.Advances in our understanding of the role of the gut microbiome in regulating many aspects of human physiology hold the promise of evolving our view of human nutrition by establishing mechanistic connections between the foods we consume and how they affect health status. One manifestation of this effort is a series of studies, performed on well-phenotyped cohorts, that seek to relate features of gut microbial community composition (organisms, genes), dietary practices, and pre- and postprandial cardiometabolic responses to test meals (1–4). A key question raised by these initiatives relates to the nature of the “bioactive” components of foods. Specifically, what are the nutrients utilized by various gut community members or microbiome-encoded metabolic pathways? What products are produced by biotransformation of these nutrients? How are these products linked to specific host physiologic (or pathophysiologic) processes?Plant-derived dietary fibers represent a “poster child” for these efforts and illustrate the formidable challenges faced. The health benefits of dietary fibers are widely known, as is their inadequate representation in Western diets. However, natural fibers are structurally complex and highly diverse. They contain numerous, typically undefined polysaccharide structures and largely unspecified protein, lipid, and small molecule constituents. Their composition varies as a function of their origin (food staple and cultivar), the different methods employed to recover them from these sources, as well as the different techniques used to incorporate them into processed foods with acceptable organoleptic properties (5). Moreover, analyzing the host effects of metabolism of different fibers is confounded by the fact that there is substantial intra- and interpersonal variation in microbiome configuration (6, 7).Snacking is becoming an ever more dominant feature of daily life worldwide and thus provides an opportunity to introduce nutritious ingredients, such as fibers, into diets. However, obtaining structure-activity relationships for specific fiber types and their corresponding targets in the gut community is foundational for designing snack foods that evoke and/or reinforce microbiome responses that are beneficial to the host.Degradation of dietary polysaccharides is a function primarily performed by bacterial carbohydrate-active enzymes (CAZymes). The gut microbiome harbors tens of thousands of CAZyme genes belonging to at least 136 glycoside hydrolase (GH) and 29 polysaccharide lyase (PL) families [extrapolated and updated from El Kaoutari et al. (8)]. In contrast, the human genome only contains 98 GH and no PL genes (9), of which <20% contribute to the processing of dietary glycans.In the current study, we test the effects of dietary supplementation with two snack food prototypes, one containing pea fiber and the other orange fiber, in two pilot studies of overweight and obese individuals consuming their normal, unrestricted diets. Our strategy was to focus on fiber-associated changes in the abundances of microbial GH and PL genes to determine whether responses to the pea or orange fiber prototypes in the gut microbiome and host are decipherable against a background of varying dietary practices and starting microbiome configurations. Higher order singular value decomposition (10) was utilized as a feature selection tool to identify treatment-discriminating changes in GH and PL gene representation. Mass spectrometric assays of the levels of fecal glycan structures (glycosidic linkages) were subsequently performed and the results were correlated with changes in the abundances of treatment-discriminating GH and PL genes with known or predicted substrate specificities. Our analysis concluded by measuring changes in levels of 1,305 plasma proteins in each study participant as a function of fiber treatment and applying computational tools to identify links between these microbiome and plasma proteome changes in response to fiber consumption. Our results provide an approach, using pilot human studies, for selecting specific fiber preparations, plus informative microbiome and host biomarkers, that can be advanced to proof-of-concept clinical trials which assess their capacity for precise manipulation of microbiome and host features. 相似文献
48.
James Stacey Taylor 《HEC forum》2013,25(4):285-287
49.
Pamina M. Gorbach Barbara S. Mensch Marla Husnik Astou Coly Benoit Mâsse Bonus Makanani Chiwawa Nkhoma Lameck Chinula Tchangani Tembo Stan Mierzwa Kimberly Reynolds Stacey Hurst Anne Coletti Andrew Forsyth 《AIDS and behavior》2013,17(2):790-800
In a microbicide safety and effectiveness trial (HPTN 035) in Malawi, 585 women completed the same questionnaire through a face-to-face interview (FTFI) and an audio computer-assisted self-interview (ACASI). Concordance between FTFI and ACASI responses ranged from 72.0 % for frequency of sex in the past week to 95.2 % for anal intercourse (AI) in the past 3 months. Reported gel and condom use at last sex act were marginally lower with ACASI than FTFI (73.5 % vs. 77.2 %, p = 0.11 and 60.9 % vs. 65.5 %, p = 0.05, respectively). More women reported AI with ACASI than FTFI (5.0 % vs. 0.2 %, p < 0.001). Analyses of consistency of responses within ACASI revealed that 15.0 % of participants in the condom-only arm and 28.7 % in the gel arm provided at least one discrepant answer regarding total sex acts and sex acts where condom and gel were used (19.2 % reported one inconsistent answer, 8.1 % reported two inconsistent answers, and 1.4 % reported three inconsistent answers). While ACASI may provide more accurate assessments of sensitive behaviors in HIV prevention trials, it also results in a high level of internally inconsistent responses. 相似文献
50.
Mari S. Golub Stacey L. Germann Renee S. Araiza J. Rachel Reader Stephen M. Griffey K. C. Kent Lloyd 《Nutritional neuroscience》2013,16(4):239-244
AbstractThe Hfe( - / - ) mouse is a model for human hereditary hemochromatosis (HHH). The accumulation of tissue iron in this condition has led to the suggestion that HHH patients may be at higher risk for neurodegenerative diseases. In this study, adult male Hfe( - / - ) mice and wildtype controls ( n = 12/group) were evaluated for impairment with motor tests (stride length, landing footsplay, rotarod) as well as a general observational battery (Functional Observational Battery, FOB). Hfe( - / - ) mice were characterized by more falls from the rotarod, wider forelimb landing footsplay and hypersensitivity to proximal stimulation. Iron accumulation in brain was not detected by histopathology. These data suggest that a motor syndrome may be associated with HHH that could be further understood through the Hfe( - / - ) mouse model. 相似文献