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291.
BackgroundCirculating biomarkers are associated with the development of coronary heart disease (CHD) and its complications by reflecting pathophysiological pathways and/or organ dysfunction. We explored the associations between 157 cardiovascular (CV) and inflammatory biomarkers and CV death using proximity extension assays (PEA) in patients with chronic CHD.Methods and findingsThe derivation cohort consisted of 605 cases with CV death and 2,788 randomly selected non-cases during 3–5 years follow-up included in the STabilization of Atherosclerotic plaque By Initiation of darapLadIb TherapY (STABILITY) trial between 2008 and 2010. The replication cohort consisted of 245 cases and 1,042 non-cases during 12 years follow-up included in the Ludwigshafen Risk and Cardiovascular Health (LURIC) study between 1997 and 2000. Biomarker levels were measured with conventional immunoassays and/or with the OLINK PEA panels CVD I and Inflammation. Associations with CV death were evaluated by Random Survival Forest (RF) and Cox regression analyses.Both cohorts had the same median age (65 years) and 20% smokers, while there were slight differences in male sex (82% and 76%), hypertension (70% and 78%), and diabetes (39% and 30%) in the respective STABILITY and LURIC cohorts. The analyses identified 18 biomarkers with confirmed independent association with CV death by Boruta analyses and statistical significance (all p < 0.0001) by Cox regression when adjusted for clinical characteristics in both cohorts. Most prognostic information was carried by N-terminal prohormone of brain natriuretic peptide (NTproBNP), hazard ratio (HR for 1 standard deviation [SD] increase of the log scale of the distribution of the biomarker in the replication cohort) 2.079 (95% confidence interval [CI] 1.799–2.402), and high-sensitivity troponin T (cTnT-hs) HR 1.715 (95% CI 1.491–1.973). The other proteins with independent associations were growth differentiation factor 15 (GDF-15) HR 1.728 (95% CI 1.527–1.955), transmembrane immunoglobulin and mucin domain protein (TIM-1) HR 1.555 (95% CI 1.362–1.775), renin HR 1.501 (95% CI 1.305–1.727), osteoprotegerin (OPG) HR 1.488 (95% CI 1.297–1.708), soluble suppression of tumorigenesis 2 protein (sST2) HR 1.478 (95% CI 1.307–1.672), cystatin-C (Cys-C) HR 1.370 (95% CI 1.243–1.510), tumor necrosis factor-related apoptosis-inducing ligand receptor 2 (TRAIL-R2) HR 1.205 (95% CI 1.131–1.285), carbohydrate antigen 125 (CA-125) HR 1.347 (95% CI 1.226–1.479), brain natriuretic peptide (BNP) HR 1.399 (95% CI 1.255–1.561), interleukin 6 (IL-6) HR 1.478 (95% CI 1.316–1.659), hepatocyte growth factor (HGF) HR 1.259 (95% CI 1.134–1.396), spondin-1 HR 1.295 (95% CI 1.156–1.450), fibroblast growth factor 23 (FGF-23) HR 1.349 (95% CI 1.237–1.472), chitinase-3 like protein 1 (CHI3L1) HR 1.284 (95% CI 1.129–1.461), tumor necrosis factor receptor 1 (TNF-R1) HR 1.486 (95% CI 1.307–1.689), and adrenomedullin (AM) HR 1.750 (95% CI 1.490–2.056).The study is limited by the differences in design, size, and length of follow-up of the 2 studies and the lack of results from coronary angiograms and follow-up of nonfatal events.ConclusionsProfiles of levels of multiple plasma proteins might be useful for the identification of different pathophysiological pathways associated with an increased risk of CV death in patients with chronic CHD.Trial registrationClinicalTrials.gov NCT00799903.

Niclas Eriksson and colleagues report associations between 157 cardiovascular plasma biomarkers and cardiovascular death in patients.  相似文献   
292.
Abstract: In some families with amyotrophic lateral sclerosis (ALS), the disease is linked to mutations in the gene encoding CuZn-superoxide dismutase. The mutant CuZn-superoxide dismutases appear to cause motor neuron degeneration by a toxic property, suggested to be linked to an altered reactivity of the active-site Cu ions. Asp90Ala mutant CuZn-superoxide dismutase was isolated from six patients with ALS, allowing properties of the mutant enzyme synthesized and conditioned in patients with ALS to be examined. The molecular mass of the Asp90Ala mutant CuZn-superoxide dismutase was 45 Da lower than that of the wild-type enzyme, as expected from the amino acid exchange. The mobility after sodium dodecyl sulfate-polyacrylamide gel electrophoresis was markedly increased, however, suggesting altered properties of the polypeptide. The mutant CuZn-superoxide dismutase showed a minimal reduction in stability but did not differ significantly from the wild-type enzyme in enzymic activity, in content and affinity for active-site Cu ions and in the propensity to catalyze formation of hydroxyl radicals. Our findings suggest that the deleterious effect of mutant CuZn-superoxide dismutases on motor neurons in ALS is not related to altered reactivity of active-site Cu ions, resulting in increased oxidant stress. Attention should therefore also be directed at other mechanisms and properties of the mutant polypeptides and their degradation products.  相似文献   
293.
294.
Climate change is projected to cause increased inflow of terrestrial dissolved organic matter to coastal areas in northerly regions. Estuarine bacterial community will thereby receive larger loads of organic matter and inorganic nutrients available for microbial metabolism. The composition of the bacterial community and its ecological functions may thus be affected. We studied the responses of bacterial community to inflow of terrestrial dissolved organic matter in a subarctic estuary in the northern Baltic Sea, using a 16S rRNA gene metabarcoding approach. Betaproteobacteria dominated during the spring river flush, constituting ~ 60% of the bacterial community. Bacterial diversity increased as the runoff decreased during summer, when Verrucomicrobia, Betaproteobacteria, Bacteroidetes, Gammaproteobacteria and Planctomycetes dominated the community. Network analysis revealed that a larger number of associations between bacterial populations occurred during the summer than in spring. Betaproteobacteria and Bacteroidetes populations appeared to display similar correlations to environmental factors. In spring, freshly discharged organic matter favoured specialists, while in summer a mix of autochthonous and terrestrial organic matter promoted the development of generalists. Our study indicates that increased inflows of terrestrial organic matter-loaded freshwater to coastal areas would promote specialist bacteria, which in turn might enhance the transformation of terrestrial organic matter in estuarine environments.  相似文献   
295.
Climate change has been suggested to lead to higher temperature and increased heterotrophy in aquatic systems. The aim of this study was to test how these two factors affect metazooplankton and food web efficiency (FWE was defined as metazooplankton production divided by basal production). We tested the following hypotheses: (1) that lower metazooplankton production and lower FWE would be found in a food web based on heterotrophic production (bacteria) relative to one based on autotrophic production (phytoplankton), since the former induces a larger number of trophic levels; (2) the metazooplankton in the heterotrophic food web would contain less essential fatty acids than those from the autotrophic food web; and (3) that higher temperature would lead to increased FWE. To test these hypotheses, a mesocosm experiment was established at two different temperatures (5 and 10°C) with a dominance of either autotrophic (NP) or heterotrophic basal production (CNP). Metazooplankton production increased with temperature, but was not significantly affected by differences in basal production. However, increased heterotrophy did lead to decreased fatty acid content and lower individual weight in the zooplankton. FWE increased with autotrophy and temperature in the following order: 5CNP < 10CNP < 5NP < 10NP. Our results indicate that in the climate change scenario we considered, the temperature will have a positive effect on FWE, whereas the increase in heterotrophy will have a negative effect on FWE. Furthermore, the quality and individual weight of the metazooplankton will be reduced, with possible negative effects on higher trophic levels.  相似文献   
296.
Bombesin belongs to a family of peptides acting as local hormones with roles in growth regulation, neural function and secretion. Upon binding to its receptor bombesin primarily elicits an increase of inositolphosphates and diacylglycerol, events leading to increased [Ca2+]i and activation of protein kinase C. When asynchronously growing V79 Chinese hamster cells were treated with bombesin in the 10−9−10−7 M concentration range their content of inositolphosphates increased and so did the frequency of mitotic cells with abnormal chromosomal arrangements (c-mitoses). Both effects were abolished by simultaneous addition of the synthetic peptide antagonist D-Arg1,D-Phe5,D-Trpu9-Leu11-substance P that binds to certain bombesin receptors. These results demonstrate that the V79 cells most probably have receptors for bombesin and that the weak but significant c-mitotic effect is mediated by such receptors.  相似文献   
297.
298.
The characteristics of the luminol-amplified chemiluminescence (CL) induced in mononuclear phagocytes interacting with PMA, FMLP or ionomycin were determined. Azide reduced the CL activity by more than 80%, while superoxide dismutase and catalase had minor effect on the monocyte CL response. The sensitivity of the monocyte CL response, to the addition of extra peroxidase differed depending on the stimulus used. Furthermore, no direct correlation was obtained between the CL response and superoxide anion or hydrogen peroxide production. In comparison with the response in granulocytes, minor quantitative differences were observed. The mechanism for the light-generating reaction, seems to be the same in both cell types.  相似文献   
299.

Background  

Computerized diagnostic information offers potential for epidemiological research; however data accuracy must be addressed. The principal aim of this study was to evaluate the completeness and correctness of diagnostic information in a computerized equine clinical database compared to corresponding hand written veterinary clinical records, used as gold standard, and to assess factors related to correctness. Further, the aim was to investigate completeness (epidemiologic sensitivity), correctness (positive predictive value), specificity and prevalence for diagnoses for four body systems and correctness for affected limb information for four joint diseases.  相似文献   
300.
Gaucher disease type III (GD) is found at a high frequency in northern Sweden. The contemporary Swedish index families are found in two geographically distinct clusters with the highest world-wide frequency of type III GD. A single T-to-C transition in exon 10 has previously been identified in patients from one of the two isolates and we report there the same mutation in the second isolate. Mutational analysis was combined with a genealogical reconstruction of 19 contemporary index families. Both clusters were traced back to two corresponding pairs of ancestors over a 9–13 generation span. Molecular studies show that the two clusters are compatible with a single founder who arrived in northern Sweden in or before the 16th century.  相似文献   
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