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61.
62.
Changing of the guards: EMA warning on paternal use of mycophenolate mofetil: An unnecessary and insufficiently substantiated precaution 下载免费PDF全文
63.
Lotte?IllerisEmail author Torben?R?jle?Christensen Mihael?Mastepanov 《Biogeochemistry》2004,70(3):315-330
Carbon fluxes between natural ecosystems and the atmosphere have received increased attention in recent years due to the impact they have on climate. In order to investigate independently how soil moisture and temperature control carbon fluxes into and out of a dry subarctic dwarf shrub dominated heath, monoliths containing soil and plants were incubated at three different moisture levels and subjected to four different temperature levels between 7 and 20 °C. Ecosystem CO2 exchange was monitored continuously day and night during the 16 to 18 days that each of three experiments lasted. Additionally, the carbon allocation pattern of the plants was investigated by labelling monoliths with 14CO2 followed by harvest of above and below ground plant parts. The results revealed that the three different soil moisture levels caused distinctly differing levels of CO2 fluxes. Also, both carbon fixation calculated as gross ecosystem production (GEP) and carbon release measured as ecosystem respiration (ER) increased with increasing temperatures, with ER increasing faster than GEP. Hence, short term carbon loss from the ecosystem accelerated with raised temperatures. Temperature sensitivity of the ecosystem was dependent on the soil moisture level, shown by differing Q10 values of both GEP and ER at different soil moisture levels. It is therefore highly important to take soil moisture levels into consideration when evaluating responses of ecosystem carbon balance to changes in temperature. The greatest C fixation took place via the two most dominant species of the ecosystem, Vaccinium uliginosum and Empetrum hermaphroditum, with the former being responsible for the different size of C fixation at the three moisture levels. 相似文献
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Camilla Noelle Rathcke Johan Holmkvist Lise Lotte N. Husmoen Torben Hansen Oluf Pedersen Henrik Vestergaard Allan Linneberg 《PloS one》2009,4(7)
Background
YKL-40 is a chitinase-like glycoprotein encoded by the chitinase 3-like 1 gene, CHI3L1, localized at chromosome 1q32.1. Increased levels of serum YKL-40 have been reported to be a biomarker for asthma and a reduced lung function. Interestingly, the C-allele of the -131 C→G (rs4950928) polymorphism of CHI3L1 has been shown to associate with bronchial hyperresponsiveness and reduced lung function suggesting that variations in CHI3L1 may influence risk of asthma. The objective of the present study was to investigate the association of common variation in the CHI3L1 locus with asthma, atopy and lung function in a large population-based sample of adults.Methods/Principal Findings
Eleven single nucleotide polymorphisms (SNPs) of CHI3L1 including rs4950928 were genotyped in 6514 individuals. Asthma was defined as self-reported history of physician-diagnosed asthma. Total IgE and specific IgE to inhalant allergens were measured on serum samples. Lung function was measured by spirometry. Homozygosity of the rs4950928 G allele as compared to homozygosity of the C allele was associated with self-reported physician diagnosed asthma (OR 1.5 (95% CI, 1.00–2.26)) and with prevalence of atopic asthma (OR 1.93 (95% CI, 1.21–3.07)) after adjustment for age, sex, smoking status, socio-economic class and BMI. Carriers of rs883125 G allele had a significantly lower prevalence of atopy (OR 0.82 (CI, 0.72; 0.94)) as compared to homozygosity of the C allele. None of the SNPs examined were significantly associated with FEV1. However, two SNPs (rs10399931and rs4950930) appeared to be significantly associated with FEV1/FVC-ratio. Subgroup analyses of never-smokers did not consistently influence the associations in an either positively og negatively way.Conclusions
In contrast to previous studies, the rs4950928 G allele, and not the C allele, was found to be associated with asthma. A few other SNPs of the CHI3L1 was found to be significantly associated with atopy and FEV1/FVC ratio, respectively. Thus, more studies seem warranted to establish the role of CHI3L1 gene in asthma and atopy. 相似文献66.
67.
Vogel LK Larsen JE Hansen M Truffer R 《Biochemical and biophysical research communications》2005,330(3):665-672
Previously it was shown that fusion proteins containing the amino terminus of an apical targeted member of the serpin family fused to the corresponding carboxyl terminus of the non-polarized secreted serpin, antithrombin, are secreted mainly to the apical side of MDCK cells. The present study shows that this is neither due to the transfer of an apical sorting signal from the apically expressed proteins, since a sequence of random amino acids acts the same, nor is it due to the deletion of a conserved signal for correct targeting from the non-polarized secreted protein. Our results suggest that the polarity of secretion is determined by conformational sensitive sorting signals. 相似文献
68.
Programmed cell death is of ultimate importance in embryonic development of animals. Now, programmed cell death has been shown to be an integral part of a multicellular developmental program in the bacterium Myxococcus xanthus. 相似文献
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Engell-Noerregaard L Hansen TH Andersen MH Thor Straten P Svane IM 《Cancer immunology, immunotherapy : CII》2009,58(1):1-14
During the past years numerous clinical trials have been carried out to assess the ability of dendritic cell (DC) based immunotherapy
to induce clinically relevant immune responses in patients with malignant diseases. A broad range of cancer types have been
targeted including malignant melanoma which in the disseminated stage have a very poor prognosis and only limited treatment
options with moderate effectiveness. Herein we describe the results of a focused search of recently published clinical studies
on dendritic cell vaccination in melanoma and review different vaccine parameters which are frequently claimed to have a possible
influence on clinical response. These parameters include performance status, type of antigen, DC maturation status, route
of vaccine administration, use of adjuvant, and vaccine induced immune response. In total, 38 articles found through Medline
search, have been included for analysis covering a total of 626 patients with malignant melanoma treated with DC based therapy.
Clinical response (CR, PR and SD) were found to be significantly correlated with the use of peptide antigens (p = 0.03), the use of any helper antigen/adjuvant (p = 0.002), and induction of antigen specific T cells (p = 0.0004). No significant correlations between objective response (CR and PR) and the tested parameters were found. However,
a few non-significant trends were demonstrated; these included an association between objective response and use of immature
DCs (p = 0.08), use of adjuvant (p = 0.09), and use of autologous antigen preparation (p = 0.12). The categorisation of SD in the response group is debatable. Nevertheless, when the SD group were analysed separately
we found that SD was significantly associated with use of peptide antigens (p = 0.0004), use of adjuvant (p = 0.01), and induction of antigen specific T cells (p = 0.0003). No specific route of vaccine administration showed superiority. Important lessons can be learned from previous
studies, interpretation of these findings should, however, be done with reservation for the many minor deviations in the different
treatment schedules among the published studies, which were not considered in order to be able to process and group the data. 相似文献