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91.
Chiriboga DE Ma Y Li W Olendzki BC Pagoto SL Merriam PA Matthews CE Hebert JR Ockene IS 《Obesity (Silver Spring, Md.)》2008,16(1):137-145
Background: Overweight and obesity are important predictors of a wide variety of health problems. Analysis of naturally occurring changes in body weight can provide valuable insights in improving our understanding of the influence of demographic, lifestyle, and psychosocial factors on weight gain in middle‐age adults. Objective: To identify gender‐specific predictors of body weight using cross‐sectional and longitudinal analyses. Methods and Procedures: Anthropometric, lifestyle and psychosocial factors were measured at baseline and then quarterly for 1 year in 572 healthy adult volunteers from Central Massachusetts who were recruited between 1994 and 1998. Linear mixed models were used to analyze the relationship between body weight and potential predictors, including demographic (e.g., age, educational level), lifestyle (e.g., diet, physical activity, smoking), and psychosocial (e.g., anxiety, depression) factors. Results: Over the 1‐year study period, on average, men gained 0.3 kg and women lost 0.2 kg. Predictors of lower body weight at baseline in both men and women included current cigarette smoking, greater leisure‐time physical activity, and lower depression and anxiety scores. Lower body weights were associated with a lower percentage of caloric intake from protein and greater occupational physical activity levels only among men; and with higher education level only among women. Longitudinal predictors of 1‐year weight gain among women included increased total caloric intake and decreased leisure‐time physical activity, and among men, greater anxiety scores. Discussion: Demographic, lifestyle and psychosocial factors are independently related to naturally occurring changes in body weight and have marked differential gender effects. These effects should be taken into consideration when designing interventions for weight‐loss and maintenance at the individual and population levels. 相似文献
92.
Wang L Guo Y Huang WJ Ke X Poyet JL Manji GA Merriam S Glucksmann MA DiStefano PS Alnemri ES Bertin J 《The Journal of biological chemistry》2001,276(24):21405-21409
BCL10 belongs to the caspase recruitment domain (CARD) family of proteins that regulate apoptosis and NF-kappaB signaling pathways. Analysis of BCL10-deficient mice has revealed that BCL10 mediates NF-kappaB activation by antigen receptors in B and T cells. We recently identified a subclass of CARD proteins (CARD9, CARD11, and CARD14) that may function to connect BCL10 to multiple upstream signaling pathways. We report here that CARD10 is a novel BCL10 interactor that belongs to the membrane-associated guanylate kinase family, a class of proteins that function to organize signaling complexes at plasma membranes. When expressed in cells, CARD10 binds to BCL10 and signals the activation of NF-kappaB through its N-terminal effector CARD domain. We propose that CARD10 functions as a molecular scaffold for the assembly of a BCL10 signaling complex that activates NF-kappaB. 相似文献
93.
Bertin J Wang L Guo Y Jacobson MD Poyet JL Srinivasula SM Merriam S DiStefano PS Alnemri ES 《The Journal of biological chemistry》2001,276(15):11877-11882
The caspase recruitment domain (CARD) is a protein-binding module that mediates the assembly of CARD-containing proteins into apoptosis and NF-kappaB signaling complexes. We report here that CARD protein 11 (CARD11) and CARD protein 14 (CARD14) are novel CARD-containing proteins that belong to the membrane-associated guanylate kinase (MAGUK) family, a class of proteins that functions as molecular scaffolds for the assembly of multiprotein complexes at specialized regions of the plasma membrane. CARD11 and CARD14 have homologous structures consisting of an N-terminal CARD domain, a central coiled-coil domain, and a C-terminal tripartite domain comprised of a PDZ domain, an Src homology 3 domain, and a GUK domain with homology to guanylate kinase. The CARD domains of both CARD11 and CARD14 associate specifically with the CARD domain of BCL10, a signaling protein that activates NF-kappaB through the IkappaB kinase complex in response to upstream stimuli. When expressed in cells, CARD11 and CARD14 activate NF-kappaB and induce the phosphorylation of BCL10. These findings suggest that CARD11 and CARD14 are novel MAGUK family members that function as upstream activators of BCL10 and NF-kappaB signaling. 相似文献
94.
CARD9 is a novel caspase recruitment domain-containing protein that interacts with BCL10/CLAP and activates NF-kappa B 总被引:5,自引:0,他引:5
Bertin J Guo Y Wang L Srinivasula SM Jacobson MD Poyet JL Merriam S Du MQ Dyer MJ Robison KE DiStefano PS Alnemri ES 《The Journal of biological chemistry》2000,275(52):41082-41086
BCL10/CLAP is an activator of apoptosis and NF-kappaB signaling pathways and has been implicated in B cell lymphomas of mucosa-associated lymphoid tissue. Although its role in apoptosis remains to be determined, BCL10 likely activates NF-kappaB through the IKK complex in response to upstream stimuli. The N-terminal caspase recruitment domain (CARD) of BCL10 has been proposed to function as an activation domain that mediates homophilic interactions with an upstream CARD-containing NF-kappaB activator. To identify upstream signaling partners of BCL10, we performed a mammalian two-hybrid analysis and identified CARD9 as a novel CARD-containing protein that interacts selectively with the CARD activation domain of BCL10. When expressed in cells, CARD9 binds to BCL10 and activates NF-kappaB. Furthermore, endogenous CARD9 is found associated with BCL10 suggesting that both proteins form a pre-existing signaling complex within cells. CARD9 also self-associates and contains extensive coiled-coil motifs that may function as oligomerization domains. We propose here that CARD9 is an upstream activator of BCL10 and NF-kappaB signaling. 相似文献
95.
Female mate preference based on male orange spot patterns in the feral guppy <Emphasis Type="Italic">Poecilia reticulata</Emphasis> in Japan 总被引:2,自引:2,他引:0
Kenji?Karinokkarino@u-gakugei.ac.jp" title="KK kkarino@u-gakugei.ac.jp" itemprop="email" data-track="click" data-track-action="Email author" data-track-label="">Email author Shinya?Shinjo 《Ichthyological Research》2004,51(4):316-320
It is known that females prefer males with larger and/or brighter orange spots in many populations of the guppy Poecilia reticulata. However, female preference for male orange spots varies among populations and changes within several years when they are introduced into new habitats with different environment. Guppies were introduced into Okinawa, Japan, more than 20 years ago and were subjected to natural and sexual selection for a long period. The female preference for orange spot patterns of males was examined by the dichotomous choice experiment for a feral guppy population of the Hiji River, Okinawa. We chose full-sibling males as a pair of stimulus males that were simultaneously presented to a test female, because sibling males should resemble each other. To create different orange spot patterns between stimulus males, one male of the stimulus male pair was fed carotenoid-supplement food such as algae and another male was fed low-carotenoid food. High-carotenoid-treatment males showed not only brighter coloration of orange spots but also larger spots than other males as a result of this dietary-manipulation. In the dichotomous choice experiment, females preferred the high-carotenoid-treatment males. In addition, logistic regression analysis clarified that brighter coloration of male orange spots was the most important factor for female mate preference. This finding suggests indirect benefits of female preference for male orange spot patterns if the male foraging ability for algae were heritable. 相似文献
96.
Coldwater fishes in streams, such as brook trout (Salvelinus fontinalis), typically are headwater specialists that occasionally expand distributions downstream to larger water bodies. It is unclear, however, whether larger streams function simply as dispersal corridors connecting headwater subpopulations, or as critical foraging habitat needed to sustain large mobile brook trout. Stable isotopes (δ13C and δ15N) and a hierarchical Bayesian mixing model analysis was used to identify brook trout that foraged in main stem versus headwater streams of the Shavers Fork watershed, West Virginia. Headwater subpopulations were composed of headwater and to a lesser extent main stem foraging individuals. However, there was a strong relationship between brook trout size and main stem prey contributions. The average brook trout foraging on headwater prey were limited to 126 mm standard length. This size was identified by mixing models as a point where productivity support switched from headwater to main stem dependency. These results, similar to other studies conducted in this watershed, support the hypothesis that productive main stem habitat maintain large brook trout and potentially facilitates dispersal among headwater subpopulations. Consequently, loss of supplementary main stem foraging habitats may explain loss of large, mobile fish and subsequent isolation of headwater subpopulations in other central Appalachian watersheds. 相似文献
97.
Astringency of aqueous solutions of phenolic compounds (grape seed tannins,
tannic acid, catechin and gallic acid) increased upon addition of citric
acid, whereas the astringency of alum was reduced. Astringency of alum was
decreased equivalently by addition of equi-sour levels of lactic acid,
citric acid or hydrochloric acid. The difference between alum and the
phenolic compounds is speculated to result from chemical modifications
affecting binding of the astringents with oral proteins rather than
cognitive differences. Chelation of the aluminum ion in alum by acids
reduces its availability for interacting with salivary proteins or
epithelial proteins. In contrast, the increased astringency produced upon
acidification of phenolic compounds is speculated to result from the pH
driven increase in the affinity of the phenols for binding with proteins.
These results suggest that alum cannot be used interchangeably with
phenolic astringents in psychophysical studies.
相似文献
98.
Heterozygous replicative form molecules of bacteriophage X174 deoxyribonucleic acid (DNA) have been constructed in vitro. These are composed of viral strands extracted from purified preparations of phage bearing ts mutations and complementary strands of either half length or full length synthesized with purified DNA polymerase, in vitro, on DNA from am3 phage. In infections with such heterozygous DNA, involving mutations in each of four different cistrons, phage with the genotype of the complementary strand comprised 1 to 20% of the total phage produced by a spheroplast population. From single-burst analysis of the progeny from DNA heterozygous in one cistron (B), it appears that those phage with the genotype of the complementary strand arise as major components in a small proportion of the infected cells rather than comprising a minor component in most cells. The implications of such a pattern of expression are discussed with respect to mechanisms of phage DNA synthesis. 相似文献
99.
Livestock grazing affects vernal pool specialists more than habitat generalists in montane vernal pools 下载免费PDF全文
Questions
Do livestock grazing and seasonal precipitation structure species composition in montane vernal pools? Which grazing and precipitation variables best predict cover of vernal pool specialists and species with broader habitat requirements? Is vernal pool species diversity correlated with livestock exclosure, and at what spatial scales?Location
Montane vernal pools, northeast California, USA.Methods
Vegetation was sampled in 20 vernal pools, including pools where livestock had been excluded for up to 20 years We compared plant species composition, functional group composition and species diversity among sites that varied in grazing history and seasonal precipitation using CCA and LMM.Results
Although vernal pool specialists were dominant in montane vernal pools, over a third of plant cover was comprised of species that occur over a broad range of wetland or upland environments. The species composition of vernal pool plant communities was influenced by both livestock grazing and precipitation patterns, however the relative effects of these environmental variables differed by functional group. Livestock exclosures favoured perennial vernal pool specialists over annual vernal pool specialists. In contrast, the cover of habitat generalists was more strongly influenced by seasonal precipitation than livestock grazing. At small spatial scales, species richness and diversity decreased as the number of years a pool had been fenced increased, but this relationship was not significant at a larger spatial scale.Conclusions
Both livestock grazing and seasonal precipitation structure the montane vernal pool plant community. We found that livestock grazing promotes the cover of annual vernal pool specialists, but at the expense of perennial vernal pool specialists. Wetter vernal pools, however, support higher cover of wetland generalist species regardless of whether pools are grazed. 相似文献100.
Nullisomic Tetrahymena. II. a Set of Nullisomics Define the Germinal Chromosomes 总被引:7,自引:2,他引:5 下载免费PDF全文
Crosses of a diploid Tetrahymena thermophila to a strain with a haploid germinal nucleus result in chromosome loss during meiosis in the haploid. The resulting monosomics can be made nullisomic by a special cross that induces homozygosis of a meiotic product of the germinal nucleus, but retention of the parental somatic nucleus. The creation and testing of single nullisomics for three of the five chromosome pairs and a triple nullisomic missing another pair is presented. Taken together, these strains make possible a series of crosses in which all but one of the chromosomes is missing in one parent. This set of nullisomics can, therefore, be used to map any mutation in Tetrahymena to a specific chromosome. 相似文献