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Objective: Obesity is a prevalent public health problem in the United States, especially for rural African American women, and causes increased morbidity and mortality. The purpose of this analysis was to determine whether the transtheoretical stages of change model was generalizable to weight loss intention among overweight and obese rural African American women and to identify important predictors of the stages of change. Research Methods and Procedures: The study was conducted in two rural counties in central Virginia. A population‐based sample of 200 women under the age of 40 completed questionnaires concerning weight loss behavior and beliefs about weight. Ordinal logistic regression was used to predict stage of change. Results: A total of 142 of the 200 women (71%) were overweight or obese (body mass index of ≥25) and were classified into a stage of change. Overall, 30% of respondents were in the precontemplation stage, 15% in the contemplation stage, 48% in the preparation stage, 4% in the action stage, and 3% in the maintenance stage. Education, what friends think about weight, body mass index, and a scale of the positive aspects of weight loss were significant predictors of the stage of change (p < 0.05). Conclusions: Several predictors of stage were the same as those found in studies of other health behaviors, and this research provides support for applying a stages of change model for weight loss intention among rural African American women. Two predictors in particular, significance of what friends think about weight and a scale of the positive aspects of weight loss, have implications for health education initiatives and social support in weight loss interventions. 相似文献
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Veronica G. Taylor Paige A. Bommarito John J. G. Tesmer 《The Journal of biological chemistry》2016,291(10):5138-5145
Regulator of G protein signaling (RGS) proteins interact with activated Gα subunits via their RGS domains and accelerate the hydrolysis of GTP. Although the R4 subfamily of RGS proteins generally accepts both Gαi/o and Gαq/11 subunits as substrates, the R7 and R12 subfamilies select against Gαq/11. In contrast, only one RGS protein, RGS2, is known to be selective for Gαq/11. The molecular basis for this selectivity is not clear. Previously, the crystal structure of RGS2 in complex with Gαq revealed a non-canonical interaction that could be due to interfacial differences imposed by RGS2, the Gα subunit, or both. To resolve this ambiguity, the 2.6 Å crystal structure of RGS8, an R4 subfamily member, was determined in complex with Gαq. RGS8 adopts the same pose on Gαq as it does when bound to Gαi3, indicating that the non-canonical interaction of RGS2 with Gαq is due to unique features of RGS2. Based on the RGS8-Gαq structure, residues in RGS8 that contact a unique α-helical domain loop of Gαq were converted to those typically found in R12 subfamily members, and the reverse substitutions were introduced into RGS10, an R12 subfamily member. Although these substitutions perturbed their ability to stimulate GTP hydrolysis, they did not reverse selectivity. Instead, selectivity for Gαq seems more likely determined by whether strong contacts can be maintained between α6 of the RGS domain and Switch III of Gαq, regions of high sequence and conformational diversity in both protein families. 相似文献
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We have studied laminin and fibronectin expression in a collection of rat cerebellar neural cell lines transformed with a mutant of Rous sarcoma virus which is temperature sensitive for transformation. We show that regardless of their neuronal or glial properties the cell lines produce both laminin and fibronectin. Laminin is expressed in similar amounts in cell lines grown at either the permissive or nonpermissive temperature for transformation, while fibronectin is generally expressed at higher levels in cells kept at the nonpermissive temperature. To provide further evidence that neural cells can produce laminin and fibronectin, double label immunofluorescence studies were conducted on primary cerebellar cultures. Both laminin and fibronectin were found to be present in the primary culture, and laminin was found to be associated with a subpopulation of astrocytes. 相似文献
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M. Gabriela Bidart-Bouzat Stephen Portnoy Evan H. DeLucia Ken N. Paige 《Ecology letters》2004,7(9):837-847
We lack information on how elevated CO2, and its interaction with other factors like herbivory, affect levels and patterns of trait integration in plants. We experimentally tested the hypothesis that elevated CO2 disrupts and restructures functional associations among plant traits, in the selfing annual, Arabidopsis thaliana. We tested for these effects both in the presence and absence of herbivory by larvae of the diamondback moth, Plutella xylostella. Elevated CO2, both alone and combined with moth herbivory, modified integrated trait responses. In addition, integration under different environments was genotype‐specific. These results imply that global changes in CO2 are likely to cause divergent evolutionary outcomes among populations of plants that differ in the initial structure of their quantitative genetic variation. 相似文献
599.
Sandra Rieger Hengguang Zhao Paige Martin Koichiro Abe Thomas S. Lisse 《Cell biochemistry and function》2015,33(1):1-13
The cutaneous wound repair process involves balancing a dynamic series of events ranging from inflammation, oxidative stress, cell migration, proliferation, survival and differentiation. A complex series of secreted trophic factors, cytokines, surface and intracellular proteins are expressed in a temporospatial manner to restore skin integrity after wounding. Impaired initiation, maintenance or termination of the tissue repair processes can lead to perturbed healing, necrosis, fibrosis or even cancer. Nuclear hormone receptors (NHRs) in the cutaneous environment regulate tissue repair processes such as fibroplasia and angiogenesis. Defects in functional NHRs and their ligands are associated with the clinical phenotypes of chronic non‐healing wounds and skin endocrine disorders. The functional relationship between NHRs and skin niche cells such as epidermal keratinocytes and dermal fibroblasts is pivotal for successful wound closure and permanent repair. The aim of this review is to delineate the cutaneous effects and cross‐talk of various nuclear receptors upon injury towards functional tissue restoration. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
600.
The role of 5'-nucleotidase [proceedings 总被引:1,自引:0,他引:1
A C Newby 《Biochemical Society transactions》1979,7(5):1030-1031