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JG Hansen W Gao J Dupuis GT O’Connor W Tang M Kowgier A Sood SA Gharib LJ Palmer M Fornage SR Heckbert BM Psaty SL Booth SUNLIGHT Consortium Patricia A Cassano 《Respiratory research》2015,16(1)
Background
Vitamin D is associated with lung function in cross-sectional studies, and vitamin D inadequacy is hypothesized to play a role in the pathogenesis of chronic obstructive pulmonary disease. Further data are needed to clarify the relation between vitamin D status, genetic variation in vitamin D metabolic genes, and cross-sectional and longitudinal changes in lung function in healthy adults.Methods
We estimated the association between serum 25-hydroxyvitamin D [25(OH)D] and cross-sectional forced expiratory volume in the first second (FEV1) in Framingham Heart Study (FHS) Offspring and Third Generation participants and the association between serum 25(OH)D and longitudinal change in FEV1 in Third Generation participants using linear mixed-effects models. Using a gene-based approach, we investigated the association between 241 SNPs in 6 select vitamin D metabolic genes in relation to longitudinal change in FEV1 in Offspring participants and pursued replication of these findings in a meta-analyzed set of 4 independent cohorts.Results
We found a positive cross-sectional association between 25(OH)D and FEV1 in FHS Offspring and Third Generation participants (P = 0.004). There was little or no association between 25(OH)D and longitudinal change in FEV1 in Third Generation participants (P = 0.97). In Offspring participants, the CYP2R1 gene, hypothesized to influence usual serum 25(OH)D status, was associated with longitudinal change in FEV1 (gene-based P < 0.05). The most significantly associated SNP from CYP2R1 had a consistent direction of association with FEV1 in the meta-analyzed set of replication cohorts, but the association did not reach statistical significance thresholds (P = 0.09).Conclusions
Serum 25(OH)D status was associated with cross-sectional FEV1, but not longitudinal change in FEV1. The inconsistent associations may be driven by differences in the groups studied. CYP2R1 demonstrated a gene-based association with longitudinal change in FEV1 and is a promising candidate gene for further studies.Electronic supplementary material
The online version of this article (doi:10.1186/s12931-015-0238-y) contains supplementary material, which is available to authorized users. 相似文献75.
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Question: Does the increase in Populus tremuloides cover within the Picea mariana–feathermoss domain enhance establishment and growth conditions for Abies balsamea regeneration? Location: Boreal forest of northwest Quebec, Canada. Method: To document the effect of Populus tremuloides on A. balsamea regeneration, mixed stands with a heterogeneous presence of P. tremuloides adjacent to Picea mariana‐dominated stands were selected. Abies balsamea regeneration, understorey environment and canopy composition were characterized from 531 sampling units distributed along transects covering the mixed–coniferous gradient. Abundance of understorey A. balsamea regeneration was described using three height groups: seedling (<30 cm), small sapling (30 to <100 cm) and tall sapling (100 to 300 cm). Growth characteristics were measured from 251 selected individuals of A. balsamea (<3 m). Results: Results showed that A. balsamea regeneration was generally more abundant when P. tremuloides was present in the canopy. Differences between seedling and sapling abundance along the mixed–coniferous gradient suggest that while establishment probably occurs over a wide range of substrates, the better growth conditions found under mixed stands ensure a higher survival rate for A. balsamea seedlings. Conclusions: The abundant A. balsamea regeneration observed within mixed stands of the Picea mariana–feathermoss domain suggests that the increase in P. tremuloides cover, favoured by intensive management practices and climatic change, could contribute to acceleration of the northward expansion of the A. balsamea–Betula papyrifera domain into the northern boreal forest dominated by Picea mariana. 相似文献
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Ducimetière F Lurkin A Ranchère-Vince D Decouvelaere AV Péoc'h M Istier L Chalabreysse P Muller C Alberti L Bringuier PP Scoazec JY Schott AM Bergeron C Cellier D Blay JY Ray-Coquard I 《PloS one》2011,6(8):e20294
Background
The exact overall incidence of sarcoma and sarcoma subtypes is not known. The objective of the present population-based study was to determine this incidence in a European region (Rhone-Alpes) of six million inhabitants, based on a central pathological review of the cases.Methodology/Principal Findings
From March 2005 to February 2007, pathology reports and tumor blocks were prospectively collected from the 158 pathologists of the Rhone-Alpes region. All diagnosed or suspected cases of sarcoma were collected, reviewed centrally, examined for molecular alterations and classified according to the 2002 World Health Organization classification. Of the 1287 patients screened during the study period, 748 met the criteria for inclusion in the study. The overall crude and world age-standardized incidence rates were respectively 6.2 and 4.8 per 100,000/year. Incidence rates for soft tissue, visceral and bone sarcomas were respectively 3.6, 2.0 and 0.6 per 100,000. The most frequent histological subtypes were gastrointestinal stromal tumor (18%; 1.1/100,000), unclassified sarcoma (16%; 1/100,000), liposarcoma (15%; 0.9/100,000) and leiomyosarcoma (11%; 0.7/100,000).Conclusions/Significance
The observed incidence of sarcomas was higher than expected. This study is the first detailed investigation of the crude incidence of histological and molecular subtypes of sarcomas. 相似文献78.
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This paper describes a flatbed antenna grid designed for continuous remote monitoring of fish tagged with 23 mm passive integrated transponder (PIT) tags in a natural stream with extensive spatial coverage. A range of applications of the system is presented. 相似文献
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M.?Rützler LJ?ZwiebelEmail author 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2005,191(9):777-790
Insects have an enormous impact on global public health as disease vectors and as agricultural enablers as well as pests and
olfaction is an important sensory input to their behavior. As such it is of great value to understand the interplay of the
molecular components of the olfactory system which, in addition to fostering a better understanding of insect neurobiology,
may ultimately aid in devising novel intervention strategies to reduce disease transmission or crop damage. Since the first
discovery of odorant receptors in vertebrates over a decade ago, much of our view on how the insect olfactory system might
work has been derived from observations made in vertebrates and other invertebrates, such as lobsters or nematodes. Together
with the advantages of a wide range of genetic tools, the identification of the first insect odorant receptors in Drosophila melanogaster in 1999 paved the way for rapid progress in unraveling the question of how olfactory signal transduction and processing occurs
in the fruitfly. This review intends to summarize much of this progress and to point out some areas where advances can be
expected in the near future. 相似文献