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111.
The magnitude and urgency of the biodiversity crisis is widely recognized within scientific and political organizations. However, a lack of integrated measures for biodiversity has greatly constrained the national and international response to the biodiversity crisis. Thus, integrated biodiversity indexes will greatly facilitate information transfer from science toward other areas of human society. The Nature Index framework samples scientific information on biodiversity from a variety of sources, synthesizes this information, and then transmits it in a simplified form to environmental managers, policymakers, and the public. The Nature Index optimizes information use by incorporating expert judgment, monitoring-based estimates, and model-based estimates. The index relies on a network of scientific experts, each of whom is responsible for one or more biodiversity indicators. The resulting set of indicators is supposed to represent the best available knowledge on the state of biodiversity and ecosystems in any given area. The value of each indicator is scaled relative to a reference state, i.e., a predicted value assessed by each expert for a hypothetical undisturbed or sustainably managed ecosystem. Scaled indicator values can be aggregated or disaggregated over different axes representing spatiotemporal dimensions or thematic groups. A range of scaling models can be applied to allow for different ways of interpreting the reference states, e.g., optimal situations or minimum sustainable levels. Statistical testing for differences in space or time can be implemented using Monte-Carlo simulations. This study presents the Nature Index framework and details its implementation in Norway. The results suggest that the framework is a functional, efficient, and pragmatic approach for gathering and synthesizing scientific knowledge on the state of biodiversity in any marine or terrestrial ecosystem and has general applicability worldwide.  相似文献   
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Many lifestyle-related diseases are associated with low-grade inflammation and peroxisome proliferator activated receptor γ coactivator (PGC)-1α has been suggested to be protective against low-grade inflammation. However, whether these anti-inflammatory properties affect acute inflammation is not known. The aim of the present study was therefore to investigate the role of muscle PGC-1α in acute inflammation. Quadriceps muscles were removed from 10-week old whole body PGC-1α knockout (KO), muscle specific PGC-1α KO (MKO) and muscle-specific PGC-1α overexpression mice (TG), 2 hours after an intraperitoneal injection of either 0.8 μg LPS/g body weight or saline. Basal TNFα mRNA content was lower in skeletal muscle of whole body PGC-1α KO mice and in accordance TG mice showed increased TNFα mRNA and protein level relative to WT, indicating a possible PGC-1α mediated regulation of TNFα. Basal p65 phosphorylation was increased in TG mice possibly explaining the elevated TNFα expression in these mice. Systemically, TG mice had reduced basal plasma TNFα levels compared with WT suggesting a protective effect against systemic low-grade inflammation in these animals. While TG mice reached similar TNFα levels as WT and showed more marked induction in plasma TNFα than WT after LPS injection, MKO PGC-1α mice had a reduced plasma TNFα and skeletal muscle TNFα mRNA response to LPS. In conclusion, the present findings suggest that PGC-1α enhances basal TNFα expression in skeletal muscle and indicate that PGC-1α does not exert anti-inflammatory effects during acute inflammation. Lack of skeletal muscle PGC-1α seems however to impair the acute TNFα response, which may reflect a phenotype more susceptible to infections as also observed in type 2 diabetes patients.  相似文献   
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Although treatment of multiple sclerosis (MS) with the type I interferon (IFN) IFN-β lowers disease activity, the role of endogenous type I IFN in MS remains controversial. We studied CD4+ T cells and CD4+ T cell subsets, monocytes and dendritic cells by flow cytometry and analysed the relationship with endogenous type I IFN-like activity, the effect of IFN-β therapy, and clinical and magnetic resonance imaging (MRI) disease activity in MS patients. Endogenous type I IFN activity was associated with decreased expression of the integrin subunit CD49d (VLA-4) on CD4+CD26(high) T cells (Th1 helper cells), and this effect was associated with less MRI disease activity. IFN-β therapy reduced CD49d expression on CD4+CD26(high) T cells, and the percentage of CD4+CD26(high) T cells that were CD49d(high) correlated with clinical and MRI disease activity in patients treated with IFN-β. Treatment with IFN-β also increased the percentage of CD4+ T cells expressing CD71 and HLA-DR (activated T cells), and this was associated with an increased risk of clinical disease activity. In contrast, induction of CD71 and HLA-DR was not observed in untreated MS patients with evidence of endogenous type IFN I activity. In conclusion, the effects of IFN-β treatment and endogenous type I IFN activity on VLA-4 expression are similar and associated with control of disease activity. However, immune-activating effects of treatment with IFN-β may counteract the beneficial effects of treatment and cause an insufficient response to therapy.  相似文献   
114.

Background

Atopic dermatitis has increased four-fold over the recent decades in developed countries, indicating that changes in environmental factors associated with lifestyle may play an important role in this epidemic. It has been proposed that alcohol consumption may be one contributing risk factor in this development.

Objective

To analyze the impact of alcohol intake during pregnancy on the development of atopic dermatitis during the first 7 years of life.

Method

The COPSAC cohort is a prospective, longitudinal, birth cohort study of 411 children born to mothers with a history of asthma, followed up for 7 years with scheduled visits every 6 months as well as visits for acute exacerbations of atopic dermatitis. Risk of atopic dermatitis from any alcohol consumption during pregnancy was analyzed as time-to-diagnosis and adjusted for known risk factors.

Results

177 of 411 children developed atopic dermatitis before age 7 years. We found a significant effect of alcohol intake during pregnancy on atopic dermatitis development (HR 1.44, 95% CI 1.05–1.99 p = 0.024). This conclusion was unaffected after adjustment for smoking, mother''s education and mother''s atopic dermatitis.

Limitations

The selection of a high-risk cohort, with all mothers suffering from asthma, and all children having a gestational age above 35 weeks with no congenital abnormality, systemic illness, or history of mechanical ventilation or lower airway infection.

Conclusion

Alcohol intake by pregnant women with a history of asthma, is significantly associated with an increased risk for the child for developing atopic dermatitis during the first 7 years of life.  相似文献   
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Folate is crucial for various cellular functions. Several transport mechanisms allow folate to enter the intracellular compartment with folate receptor-α being the major high-affinity receptor. Rare genetic variations in exons of the FR-α gene, FOLR1, were recently shown to cause severe folate deficiency accompanied by neurological and other disturbances. So far, similar effects by genetic variation in noncoding parts of the FOLR1 gene have not been identified. The aim of our study was to determine biochemically the haplotype structure of two linked polymorphisms in the FOLR1 gene, 1816delC and 1841G>A, the prevalences of the mutated alleles across Eurasia, and their possible effects on physiological folate levels in vivo. For this purpose we employed allele-specific PCR and Pyrosequencing technology and performed genotyping in 738 subjects from Spain, 387 from Sweden, 952 from Estonia, and 47 from Korea. We demonstrate the presence of an ancient double-mutated haplotype 1816delC–1841A in the FOLR1 gene, with the prevalence of the mutated allele being highest among Koreans (q = 0.074), lower in Estonians (q = 0.017), Spaniards (q = 0.0061), and the lowest among Swedes (q = 0.0026). Erythrocyte folate levels were studied in the Spanish population sample, where subjects carrying the double-mutated FOLR1 haplotype had significantly reduced levels by 27% (P = 0.039), adjusted for serum vitamin B12 levels and MTHFR 677C>T genotype, while the mean serum folate levels were only 20% lower among the carriers (P = 0.11). Plasma homocysteine and cobalamin levels did not differ. Thus, we have demonstrated by molecular haplotyping an ancient double-mutated haplotype 1816delC–1841A in the FOLR1 gene, spread over the whole Eurasian continent, which may be of functional importance for uptake of folate in red blood cells.  相似文献   
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Aim An understanding of the non‐breeding distribution and ecology of migratory species is necessary for successful conservation. Many seabirds spend the non‐breeding season far from land, and information on their distribution during this time is very limited. The black‐legged kittiwake, Rissa tridactyla, is a widespread and numerous seabird in the North Atlantic and Pacific, but breeding populations throughout the Atlantic range have declined recently. To help understand the reasons for the declines, we tracked adults from colonies throughout the Atlantic range over the non‐breeding season using light‐based geolocation. Location North Atlantic. Methods Geolocation data loggers were deployed on breeding kittiwakes from 19 colonies in 2008 and 2009 and retrieved in 2009 and 2010. Data from 236 loggers were processed and plotted using GIS. Size and composition of wintering populations were estimated using information on breeding population size. Results Most tracked birds spent the winter in the West Atlantic, between Newfoundland and the Mid‐Atlantic Ridge, including in offshore, deep‐water areas. Some birds (mainly local breeders) wintered in the North Sea and west of the British Isles. There was a large overlap in winter distributions of birds from different colonies, and colonies closer to each other showed larger overlap. We estimated that 80% of the 4.5 million adult kittiwakes in the Atlantic wintered west of the Mid‐Atlantic Ridge, with only birds from Ireland and western Britain staying mainly on the European side. Main conclusions The high degree of mixing in winter of kittiwakes breeding in various parts of the Atlantic range implies that the overall population could be sensitive to potentially deteriorating environmental conditions in the West Atlantic, e.g. owing to lack of food or pollution. Our approach to estimating the size and composition of wintering populations should contribute to improved management of birds faced with such challenges.  相似文献   
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