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71.
Johanna Gustafsson Iva Gunnarsson Ola B?rjesson Susanne Pettersson Sonia M?ller Guo-Zhong Fei Kerstin Elvin Julia F Simard Lars-Olof Hansson Ingrid E Lundberg Anders Larsson Elisabet Svenungsson 《Arthritis research & therapy》2009,11(6):R186
Introduction
Cardiovascular disease (CVD) is a major cause of premature mortality among Systemic lupus erythematosus (SLE) patients. Many studies have measured and evaluated risk factors for premature subclinical atherosclerosis, but few studies are prospective and few have evaluated risk factors for hard endpoints, i.e. clinically important cardiovascular events (CVE). We investigated the impact of traditional and lupus associated risk factors for the first ever CVE in a longitudinal cohort of SLE patients.Methods
A total of 182 SLE patients (mean age 43.9 years) selected to be free of CVE were included. Cardiovascular and autoimmune biomarkers were measured on samples collected after overnight fasting at baseline. Clinical information was collected at baseline and at follow up. End point was the first ever CVE (ischemic heart, cerebrovascular or peripheral vascular disease or death due to CVD). Impact of baseline characteristics/biomarkers on the risk of having a first CVE was evaluated with Cox regression.Results
Follow up was 99.5% after a mean time of 8.3 years. Twenty-four patients (13%) had a first CVE. In age-adjusted Cox regression, any positive antiphospholipid antibody (aPL), elevated markers of endothelial activation (von Willebrand factor (vWf), soluble vascular cellular adhesion molecule-1 (sVCAM-1)) and fibrinogen predicted CVEs. Of SLE manifestations, arthritis, pleuritis and previous venous occlusion were positively associated with future CVEs while thrombocytopenia was negatively associated. Among traditional risk factors only age and smoking were significant predictors. In a multivariable Cox regression model age, any positive aPL, vWf and absence of thrombocytopenia were all predictors of the first CVE.Conclusions
In addition to age, positive aPL, biomarkers indicating increased endothelial cell activity/damage, and absence of thrombocytopenia were independent predictors of CVEs in this prospective study. Our results indicate that activation of the endothelium and the coagulation system are important features in SLE related CVD. Furthermore, we observed that the risk of CVEs seems to differ between subgroups of SLE patients. 相似文献72.
73.
In the production of ethanol from lignocellulosic material, it is necessary to reach a high ethanol concentration after fermentation. Simply increasing the substrate concentration leads to stirring problems and inhibition of the enzymes and yeast in the process.Batch simultaneous saccharification and fermentation (SSF) of steam-pretreated spruce with 13.7% water-insoluble solids (WIS) (25% total solids (TS)) was run in a stirred-tank reactor as well as in two reactors designed to handle solid or semi-solid material. In all reactors, the overall ethanol yields were only between 5 and 6%. Fermentation of the liquid fraction of the steam-pretreated spruce slurry resulted in an overall ethanol yield of 85%.22 h of prehydrolysis at 48 °C prior to SSF at 32 °C significantly increased the overall ethanol yield to 72% (final ethanol concentration of 47.8 g/L), using the whole slurry of steam-pretreated spruce at a dry matter content of 13.7% WIS (25% TS). 相似文献
74.
Reiss K Kirchner E Gijzen M Zocher G Löffelhardt B Nürnberger T Stehle T Brunner F 《The Journal of biological chemistry》2011,286(49):42585-42593
Transglutaminases (TGases) are ubiquitous enzymes that catalyze selective cross-linking between protein-bound glutamine and lysine residues; the resulting isopeptide bond confers high resistance to proteolysis. Phytophthora sojae, a pathogen of soybean, secretes a Ca2+-dependent TGase (GP42) that is activating defense responses in both host and non-host plants. A GP42 fragment of 13 amino acids, termed Pep-13, was shown to be absolutely indispensable for both TGase and elicitor activity. GP42 does not share significant primary sequence similarity with known TGases from mammals or bacteria. This suggests that GP42 has evolved novel structural and catalytic features to support enzymatic activity. We have solved the crystal structure of the catalytically inactive point mutant GP42 (C290S) at 2.95 Å resolution and identified residues involved in catalysis by mutational analysis. The protein comprises three domains that assemble into an elongated structure. Although GP42 has no structural homolog, its core region displays significant similarity to the catalytic core of the Mac-1 cysteine protease from Group A Streptococcus, a member of the papain-like superfamily of cysteine proteases. Proteins that are taxonomically related to GP42 are only present in plant pathogenic oomycetes belonging to the order of the Peronosporales (e.g. Phytophthora, Hyaloperonospora, and Pythium spp.) and in marine Vibrio bacteria. This suggests that a lateral gene transfer event may have occurred between bacteria and oomycetes. Our results offer a basis to design and use highly specific inhibitors of the GP42-like TGase family that may impair the growth of important oomycete and bacterial pathogens. 相似文献
75.
Salivary free cortisol concentration, rated stress and annoyance were determined in 32 subjects before, during and after carrying out a battery of performance tasks for 2 hours during exposure to ventilation noise, with dominant low frequencies (low frequency noise) or a flat frequency spectrum (reference noise). Both noises had a level of 40 dBA. All subjects were studied on two occasions and were exposed to both noises in strict rotation. Subjects were categorised as high- or low-sensitive to noise in general and low frequency noise in particular on the basis of questionnaires. Cortisol concentrations during the task were not significantly modulated by the noises or related to noise sensitivity alone. The normal circadian decline in cortisol concentration was however significantly attenuated in subjects high-sensitive to noise in general, when they were exposed to the low frequency noise. This noise was rated as more annoying and more disruptive to working capacity than the reference noise. The study showed physiological evidence of increased stress related to noise sensitivity and noise exposure during work. This is the first study to demonstrate an effect of moderate levels of noise on neuroendocrine activity. The impact of long-term exposure to moderate noise levels, and particularly low frequency noise, in the workplace deserves further investigation. 相似文献
76.
Fredman Pam Månsson Jan-Eric Dellheden Birgitta Boström Kerstin Holst Hans Von 《Neurochemical research》1999,24(2):275-279
Altered glycosylation is a common feature in tumors of various kind and particular interest has been focused on the expression of tumor-associated gangliosides. We have previously identified some human glioma-associated gangliosides and in this study yet another, not previously described, ganglioside has been isolated. The ganglioside was prepared from human glioma tissue taken at autopsy. The new ganglioside bound cholera-toxin B-subunit and its structure was confirmed by fast atom bombardment—mass spectrometry to be NeuN-GM1 (II3NeuNH2-GgOse4Cer). In the dissected tumor specimen, the concentration of NeuN-GM1 was 0.1 mol/g wet weight and accounted for approximately 20% of the monosialoganglioside fraction. Normal human brain tissue specimens (n = 10) did not contain detectable (>0.5 nmol/g wet weight of tissue) amounts of NeuN-GM1, indicating that this ganglioside might be associated with human glioma. However, none of the 17 other tumour specimens reveal any detectable amounts of this ganglioside. In conclusion, NeuN GM1 is a glioma-associated ganglioside but its exceptional expression limits its relevance as a molecule involved in general tumor biology. 相似文献
77.
Li K Pasternak C Härtig E Haberzettl K Maxwell A Klug G 《Nucleic acids research》2004,32(15):4563-4575
The expression of many genes of facultatively photosynthetic bacteria of the genus Rhodobacter is controlled by the oxygen tension. Among these are the genes of the puf and puc operons, which encode proteins of the photosynthetic apparatus. Previous results revealed that thioredoxins are involved in the regulated expression of these operons, but it remained unsolved as to the mechanisms by which thioredoxins affect puf and puc expression. Here we show that reduced TrxA of Rhodobacter capsulatus and Rhodobacter sphaeroides and oxidized TrxC of R.capsulatus interact with DNA gyrase and alter its DNA supercoiling activity. While TrxA enhances supercoiling, TrxC exerts a negative effect on this activity. Furthermore, inhibition of gyrase activity strongly reduces puf and puc expression. Our results reveal a new signaling pathway by which oxygen can affect the expression of bacterial genes. 相似文献
78.
79.
Gilbert I Schiffmann S Rubenwolf S Jensen K Mai T Albrecht C Lankenau A Beste G Blank K Gaub HE Clausen-Schaumann H 《Proteomics》2004,4(5):1417-1420
Protein arrays permit the parallel analysis of many different markers in a small sample volume. However, the problem of cross-reactivity limits the degree of multiplexing in parallel sandwich immunoassays (using monoclonal antibodies (mAbs)), meaning antibodies must be prescreened in order to reduce false positives. In contrast, we use a second chip surface for the local application of detection antibodies, thereby efficiently eliminating antibody cross-reactions. Here, we illustrate the potential advantages of using single-chain Fv fragments rather than mAbs as capture and detection molecules with this double chip technology. 相似文献
80.