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101.
Ayedh D. Alahmari Alex J. Mackay Anant R.C. Patel Beverly S. Kowlessar Richa Singh Simon E. Brill James P. Allinson Jadwiga A. Wedzicha Gavin C. Donaldson 《Respiratory research》2015,16(1)
Rationale
Information concerning how climate and atmospheric pollutants affects physical activity in COPD patients is lacking and might be valuable in determining when physical activity should be encouraged.Methods
Seventy-three stable COPD patients recorded on daily diary cards worsening of respiratory symptoms, peak expiratory flow rate, hours spent outside the home and the number of steps taken per day. Pedometry data was recorded on 16,478 days, an average of 267 days per patient (range 29-658). Daily data for atmospheric PM10 and ozone (O3) were obtained for Bloomsbury Square, Central London from the Air Quality Information Archive databases. Daily weather data were obtained for London Heathrow from the British Atmospheric Data Archive.Results
Colder weather below 22.5 °C, reduced daily step count by 43.3 steps day per°C (95 % CI 2.14 to 84.4; p = 0.039) and activity was lower on rainy than dry days (p = 0.002) and on overcast compared to sunny days (p < 0.001). Daily step count was 434 steps per day lower on Sunday than Saturday (p < 0.001) and 353 steps per day lower on Saturday than Friday (p < 0.001). After allowance for these effects, higher O3 levels decreased activity during the whole week (-8 steps/ug/m3; p = 0.005) and at weekends (-7.8 steps/ug/m3; p = 0.032). Whilst, during the week PM10 reduced activity (p = 0.018) but not during the weekend.Conclusions
Inactivity of COPD patients is greatest on cold, wet and overcast days and at the weekends. This study also provides evidence of an independent effect of atmospheric pollution at high levels.Electronic supplementary material
The online version of this article (doi:10.1186/s12931-015-0229-z) contains supplementary material, which is available to authorized users. 相似文献102.
TGFβ signalling in endothelial cells is important for angiogenesis in early embryonic development, but little is known about its role in early postnatal life. To address this we used a tamoxifen inducible Cre-LoxP strategy in neonatal mice to deplete the TypeII TGFβ receptor (Tgfbr2) specifically in endothelial cells. This resulted in multiple micro-haemorrhages, and glomeruloid-like vascular tufts throughout the cerebral cortices and hypothalamus of the brain as well as in retinal tissues. A detailed examination of the retinal defects in these mutants revealed that endothelial adherens and tight junctions were in place, pericytes were recruited and there was no failure of vascular smooth muscle differentiation. However, the deeper retinal plexus failed to form in these mutants and the angiogenic sprouts stalled in their progress towards the inner nuclear layer. Instead the leading endothelial cells formed glomerular tufts with associated smooth muscle cells. This evidence suggests that TGFβ signalling is not required for vessel maturation, but is essential for the organised migration of endothelial cells as they begin to enter the deeper layers of the retina. Thus, TGFβ signalling is essential in vascular endothelial cells for maintaining vascular integrity at the angiogenic front as it migrates into developing neural tissues in early postnatal life. 相似文献
103.
104.
Background
In many studies, researchers may recruit samples consisting of independent trios and unrelated individuals. However, most of the currently available haplotype inference methods do not cope well with these kinds of mixed data sets.Methods
We propose a general and simple methodology using a mixture of weighted multinomial (MIXMUL) approach that combines separate haplotype information from unrelated individuals and independent trios for haplotype inference to the individual level.Results
The new MIXMUL procedure improves over existing methods in that it can accurately estimate haplotype frequencies from mixed data sets and output probable haplotype pairs in optimized reconstruction outcomes for all subjects that have contributed to estimation. Simulation results showed that this new MIXMUL procedure competes well with the EM-based method, i.e. FAMHAP, under a few assumed scenarios.Conclusion
The results showed that MIXMUL can provide accurate estimates similar to those haplotype frequencies obtained from FAMHAP and output the probable haplotype pairs in the most optimal reconstruction outcome for all subjects that have contributed to estimation. If available data consist of combinations of unrelated individuals and independent trios, the MIXMUL procedure can be used to estimate the haplotype frequencies accurately and output the most likely reconstructed haplotype pairs of each subject in the estimation. 相似文献105.
Jackie H. Myers John Beardall Graeme Allinson Scott Salzman Leanne Gunthorpe 《Hydrobiologia》2010,649(1):239-247
This study was carried out to investigate the genesis of N. spumigena blooms by specifically studying the effects of environmental variables (salinity, nitrogen, phosphorus and light) on the
germination of N. spumigena akinetes. Optimal conditions for maximum germination and germling growth were determined by exposing akinetes to a range
of salinities and nutrient (nitrogen and phosphorus) concentrations under two different irradiances. At pre-determined time
periods, treatments were sampled and the percent germination and length of germlings assessed. The results indicated that
akinete germination and germling growth were optimal at salinities from 5 to 25 and significantly reduced outside this range.
A positive correlation in germination was observed with increasing nutrient (phosphorus and nitrate) concentration. Similarly,
germling growth increased with increasing concentrations of both nutrients. Irradiance significantly influenced both germination
and growth during salinity experiments, whereas in nutrient addition experiments, irradiance had no effect on germination;
however, growth was significantly influenced during phosphorus addition experiments. Consequently, salinity and light appeared
to be most critical in the germination process for N. spumigena akinetes, with phosphorus most important for germling growth. The study showed that N. spumigena may be able to germinate under environmental conditions outside its optimal range, but the growth of the germling is significantly
reduced, which in turn suggests that its ability to form a bloom outside its optimal environmental conditions would also be
greatly reduced. 相似文献
106.
107.
Dectin-1 and TLRs permit macrophages to distinguish between different Aspergillus fumigatus cellular states 总被引:3,自引:0,他引:3
Gersuk GM Underhill DM Zhu L Marr KA 《Journal of immunology (Baltimore, Md. : 1950)》2006,176(6):3717-3724
Aspergillus fumigatus is a common cause of invasive and allergic pulmonary disease. Resting conidia of the filamentous fungus are constantly inhaled, but cause infection only after initiating hyphal growth. In this study, we have explored whether macrophages can distinguish between resting spores and the maturing, potentially invasive form of the fungus. Although macrophages bind and ingest A. fumigatus resting conidia efficiently, there is little inflammatory response; NF-kappabeta is not activated, inflammatory cytokines are not induced, and reactive oxygen species are not produced. However, maturing A. fumigatus conidia and germ tubes stimulate NF-kappabeta, secretion of proinflammatory cytokines and production of reactive oxygen by human monocyte-derived macrophages and murine macrophages from multiple anatomical sites. These responses are in part mediated by dectin-1, which binds cell wall beta-glucan that is not present on the surface of dormant conidia, but is present after cellular swelling and loss of the hydrophobic proteinaceous cell wall. Dectin-1 binding to germ tubes augments, but is not required for, TLR2-mediated inflammatory cytokine secretion. Dectin-1 recognition of germ tubes also stimulates TNF-alpha production in the absence of both TLR2 and MyD88 signaling. These data demonstrate one mechanism by which the pulmonary inflammatory response is tailored toward metabolically active cells, thereby avoiding unnecessary tissue damage with frequent inhalation of ubiquitous spores. 相似文献
108.
Allard JB Poynter ME Marr KA Cohn L Rincon M Whittaker LA 《Journal of immunology (Baltimore, Md. : 1950)》2006,177(8):5186-5194
Cystic fibrosis (CF) lung disease is characterized by persistent airway inflammation and airway infection that ultimately leads to respiratory failure. Aspergillus sp. are present in the airways of 20-40% of CF patients and are of unclear clinical significance. In this study, we demonstrate that CF transmembrane conductance regulator (CFTR)-deficient (CFTR knockout, Cftr(tm1Unc-)TgN(fatty acid-binding protein)CFTR) and mutant (DeltaF508) mice develop profound lung inflammation in response to Aspergillus fumigatus hyphal Ag exposure. CFTR-deficient mice also develop an enhanced Th2 inflammatory response to A. fumigatus, characterized by elevated IL-4 in the lung and IgE and IgG1 in serum. In contrast, CFTR deficiency does not promote a Th1 immune response. Furthermore, we demonstrate that CD4+ T cells from naive CFTR-deficient mice produce higher levels of IL-4 in response to TCR ligation than wild-type CD4+ T cells. The Th2 bias of CD4+ T cells in the absence of functional CFTR correlates with elevated nuclear levels of NFAT. Thus, CFTR is important to maintain the Th1/Th2 balance in CD4+ T cells. 相似文献
109.
Gold salts and phenylbutazone selectively inhibit the synthesis of PGF2α and PGE2 respectively. Lowered production of one prostaglandin species is accompanied by an increased production of the other. Selective inhibition by these drugs was observed in the presence of adrenaline, reduced glutathione and copper sulphate under conditions when most anti-inflammatory compounds inhibited PGE2 and PGF2α syntheses equally. It is postulated that selective inhibitors may have a different mode of action in vivo and beneficial effects may be related to the endogenous ratio of PGE to PGF required for normal function. 相似文献
110.
Cilia and flagella are rare in nongerminal tissues of anthropods, and are generally thought to be restricted to sperm and sensory cells in insects (2). Whitten (5) has reported the presence of kinetosomes at the base of mitotrichia in the dipteran fly Sarcophaga bullata, but reports no evidence of the organization of fibrous elements characteristic of cilia and or flagella. During an ultrastructural analysis of morphogenesis of the colleterial gland of the silk moth Hyalophora cecropia, we found the first example of paired flagella associated with an insect secretory cell. These structures are also unusual in that they serve a temporary role in morphogenesis and subsequently disappear at the terminal stages of differentiation. 相似文献