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91.

Background

There is mounting evidence that estimates of intakes of a range of dietary nutrients are related to both lung function level and rate of decline, but far less evidence on the relation between lung function and objective measures of serum levels of individual nutrients. The aim of this study was to conduct a comprehensive examination of the independent associations of a wide range of serum markers of nutritional status with lung function, measured as the one-second forced expiratory volume (FEV1).

Methods

Using data from the Third National Health and Nutrition Examination Survey, a US population-based cross-sectional study, we investigated the relation between 21 serum markers of potentially relevant nutrients and FEV1, with adjustment for potential confounding factors. Systematic approaches were used to guide the analysis.

Results

In a mutually adjusted model, higher serum levels of antioxidant vitamins (vitamin A, beta-cryptoxanthin, vitamin C, vitamin E), selenium, normalized calcium, chloride, and iron were independently associated with higher levels of FEV1. Higher concentrations of potassium and sodium were associated with lower FEV1.

Conclusion

Maintaining higher serum concentrations of dietary antioxidant vitamins and selenium is potentially beneficial to lung health. In addition other novel associations found in this study merit further investigation.  相似文献   
92.
Germinal‐center kinase‐like kinase (GLK, Map4k3), a GCK‐I family kinase, plays multiple roles in regulating apoptosis, amino acid sensing, and immune signaling. We describe here the crystal structure of an activation loop mutant of GLK kinase domain bound to an inhibitor. The structure reveals a weakly associated, activation‐loop swapped dimer with more than 20 amino acids of ordered density at the carboxy‐terminus. This C‐terminal PEST region binds intermolecularly to the hydrophobic groove of the N‐terminal domain of a neighboring molecule. Although the GLK activation loop mutant crystallized demonstrates reduced kinase activity, its structure demonstrates all the hallmarks of an “active” kinase, including the salt bridge between the C‐helix glutamate and the catalytic lysine. Our compound displacement data suggests that the effect of the Ser170Ala mutation in reducing kinase activity is likely due to its effect in reducing substrate peptide binding affinity rather than reducing ATP binding or ATP turnover. This report details the first structure of GLK; comparison of its activation loop sequence and P‐loop structure to that of Map4k4 suggests ideas for designing inhibitors that can distinguish between these family members to achieve selective pharmacological inhibitors.  相似文献   
93.
94.
Cells of the myeloid lineage are significant targets for human immunodeficiency virus (HIV) in humans and simian immunodeficiency virus (SIV) in monkeys. Monocytes play critical roles in innate and adaptive immunity during inflammation. We hypothesize that specific subsets of monocytes expand with AIDS and drive central nervous system (CNS) disease. Additionally, there may be expansion of cells from the bone marrow through blood with subsequent macrophage accumulation in tissues driving pathogenesis. To identify monocytes that recently emigrated from bone marrow, we used 5-bromo-2′-deoxyuridine (BrdU) labeling in a longitudinal study of SIV-infected CD8+ T lymphocyte depleted macaques. Monocyte expansion and kinetics in blood was assessed and newly migrated monocyte/macrophages were identified within the CNS. Five animals developed rapid AIDS with differing severity of SIVE. The percentages of BrdU+ monocytes in these animals increased dramatically, early after infection, peaking at necropsy where the percentage of BrdU+ monocytes correlated with the severity of SIVE. Early analysis revealed changes in the percentages of BrdU+ monocytes between slow and rapid progressors as early as 8 days and consistently by 27 days post infection. Soluble CD163 (sCD163) in plasma correlated with the percentage of BrdU+ monocytes in blood, demonstrating a relationship between monocyte activation and expansion with disease. BrdU+ monocytes/macrophages were found within perivascular spaces and SIVE lesions. The majority (80–90%) of the BrdU+ cells were Mac387+ that were not productively infected. There was a minor population of CD68+BrdU+ cells (<10%), very few of which were infected (<1% of total BrdU+ cells). Our results suggest that an increased rate of monocyte recruitment from bone marrow into the blood correlates with rapid progression to AIDS, and the magnitude of BrdU+ monocytes correlates with the severity of SIVE.  相似文献   
95.
The olfactory bulbs (OBs) are bilaterally paired structures in the vertebrate forebrain that receive and process odor information from the olfactory receptor neurons (ORNs) in the periphery. Virtually all vertebrate OBs are arranged chemotopically, with different regions of the OB processing different types of odorants. However, there is some evidence that elasmobranch fishes (sharks, rays, and skates) may possess a gross somatotopic organization instead. To test this hypothesis, we used histological staining and retrograde tracing techniques to examine the morphology and organization of ORN projections from the olfactory epithelium (OE) to the OB in three elasmobranch species with varying OB morphologies. In all three species, glomeruli in the OB received projections from ORNs located on only the three to five lamellae situated immediately anterior within the OE. These results support that the gross arrangement of the elasmobranch OB is somatotopic, an organization unique among fishes and most other vertebrates. In addition, certain elasmobranch species possess a unique OB morphology in which each OB is physically subdivided into two or more “hemi‐olfactory bulbs.” Somatotopy could provide a preadaptation which facilitated the evolution of olfactory hemibulbs in these species. J. Morphol., 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
96.
Lung function measures are heritable, predict mortality and are relevant in diagnosis of chronic obstructive pulmonary disease (COPD). COPD and asthma are diseases of the airways with major public health impacts and each have a heritable component. Genome-wide association studies of SNPs have revealed novel genetic associations with both diseases but only account for a small proportion of the heritability. Complex copy number variation may account for some of the missing heritability. A well-characterised genomic region of complex copy number variation contains beta-defensin genes (DEFB103, DEFB104 and DEFB4), which have a role in the innate immune response. Previous studies have implicated these and related genes as being associated with asthma or COPD. We hypothesised that copy number variation of these genes may play a role in lung function in the general population and in COPD and asthma risk. We undertook copy number typing of this locus in 1149 adult and 689 children using a paralogue ratio test and investigated association with COPD, asthma and lung function. Replication of findings was assessed in a larger independent sample of COPD cases and smoking controls. We found evidence for an association of beta-defensin copy number with COPD in the adult cohort (OR = 1.4, 95%CI:1.02–1.92, P = 0.039) but this finding, and findings from a previous study, were not replicated in a larger follow-up sample(OR = 0.89, 95%CI:0.72–1.07, P = 0.217). No robust evidence of association with asthma in children was observed. We found no evidence for association between beta-defensin copy number and lung function in the general populations. Our findings suggest that previous reports of association of beta-defensin copy number with COPD should be viewed with caution. Suboptimal measurement of copy number can lead to spurious associations. Further beta-defensin copy number measurement in larger sample sizes of COPD cases and children with asthma are needed.  相似文献   
97.
Different approaches to producing transgenic grapevines based on regeneration via embryogenesis were investigated. Embryogenic callus was initiated from anther tissue of Vitis vinifera cv. Sultana and three embryogenic culture types (embryogenic callus, tissue type I; proliferating embryos, tissue type II; and a suspension) were established. The three culture types were incolucaled with Agrobacterium tumefaciens harbouring a binary vector which contained a uidA reporter gene and either a hpt or nptII selectable marker gene or the cultures were bombarded with microprojectiles carrying a uidA/nptII binary vector. Transgenic plants were produced only from Agrobacterium transformation experiments. Transformed embryos were selected with kanamycin or hygromycin antibiotics and recovered with the highest efficiency from inoculated type I cultures. Southern analysis of genomic DNA extracted from ten transgenic plants showed that the number of T-DNA insertions in the genome ranged from 1 to at least 4. Evidence for methylation of the T-DNA at cytosine and adenine residues in transgenic plants was found by Southern analysis of DNA digested with two isoschizomer pairs of restriction endonucleases. No evidence for genotype alterations or somatic meiosis was found when DNA from 80 somatic embryos and seven plants regenerated from embryogenic culture were analysed at six sequence-tagged sites which are heterozygous in cv. Sultana. Expression of the uidA gene in in vitro grown leaves of transgenic plants was most often high and uniform but GUS staining was occasionally observed to be low and/or patchy. Transgenic plants and all plants regenerated from embryogenic culture produced red veined, lobed leaves which are uncharacteristic of the accepted ampelographic phenotype of Sultana. It is suggested that this phenotype may represent a juvenile growth stage.  相似文献   
98.
alpha-Amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA)-type glutamate receptors (AMPARs) mediate excitatory neurotransmission at neuronal synapses, and their regulated localization plays a role in synaptic plasticity. In Caenorhabditis elegans, the PDZ and PTB domain-containing protein LIN-10 is required both for the synaptic localization of the AMPAR subunit GLR-1 and for vulval fate induction in epithelia. Here, we examine the role that different LIN-10 domains play in GLR-1 localization. We find that an amino-terminal region of LIN-10 directs LIN-10 protein localization to the Golgi and to synaptic clusters. In addition, mutations in the carboxyl-terminal PDZ domains prevent LIN-10 from regulating GLR-1 localization in neurons but do not prevent LIN-10 from functioning in the vulval epithelia. A mutation in the amino terminus prevents the protein from functioning in the vulval epithelia but does not prevent it from functioning to regulate GLR-1 localization in neurons. Finally, we show that human Mint2 can substitute for LIN-10 to facilitate GLR-1 localization in neurons and that the Mint2 amino terminus is critical for this function. Together, our data suggest that LIN-10 uses distinct modular domains for its functions in neurons and epithelial cells and that during evolution its vertebrate ortholog Mint2 has retained the ability to direct AMPAR localization in neurons.  相似文献   
99.
We demonstrate that human umbilical vein endothelial cells (HUVEC) grown in co-culture (CC) with U87 glioblastoma cells transfected with green fluorescent protein (GFP-U87) exhibit resistance to radiation-mediated apoptosis. cDNA macroarray analysis reveals increases in the accumulation of RNAs for HUVEC genes encoding cell adhesion molecules, growth factor-related proteins, and cell cycle regulatory/DNA repair proteins. An increase in protein expression of integrin alphav, integrin beta1, MAPK(p42), Rad51, DNA-PK(CS), and ataxia telangiectasia gene (ATM) was detected in HUVEC grown in CC with GFP-U87 cells compared with HUVEC grown in mono-culture. Treatment with anti-VEGF antibody decreases the expression of integrin alphav, integrin beta1, DNA-PK(CS) and ATM with a corresponding increase in ionizing radiation (IR)-induced apoptosis. These data support the concept that endothelial cells growing in the tumor microenvironment may develop resistance to cytotoxic therapies due to the up-regulation by tumor cells of endothelial cells genes associated with survival.  相似文献   
100.
Activation of islet-specific T cells plays a significant role in the development of type 1 diabetes. In an effort to control T cell activation, we expressed the inhibitory receptor, Ly-49A, on islet-specific mouse CD4 cells. Ag-mediated activation of Ly-49A T cells was inhibited in vitro when the Ly-49A ligand, H-2D(d), was present on APCs. Ag-driven T cell proliferation, cytokine production, and changes in surface receptor expression were significantly reduced. Inhibition was also evident during secondary antigenic challenge. Addition of exogenous IL-2 did not rescue cells from inhibition, suggesting that Ly-49A engagement does not lead to T cell anergy. Importantly, in an adoptive transfer model, Ly-49A significantly delays the onset of diabetes. Together these results demonstrate that the inhibitory receptor Ly-49A effectively limits Ag-specific CD4 cell responses even in the presence of sustained autoantigen expression in vivo.  相似文献   
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