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1.
The aim of this prospective study was to determine the prevalence and localization of stenotic atherosclerotic lesions of supra-aortic arteries in diabetic patients according to age and sex. Angiograms obtained by digital subtraction angiography were analyzed in 150 diabetic patients (study group) and 150 non-diabetic patients (control group) with symptoms of cerebral ischemia. Diabetic patients were found to have a significantly higher prevalence of stenotic atherosclerotic lesions of the internal carotid artery. Lesions of the large supra-aortic arteries were significantly more common in the left than in the right side of the neck (p < 0.001), but the difference between the diabetic and the non-diabetic group did not reach statistical significance. Hemodynamic conditions were found to be more important than diabetes for the occurrence of atherosclerotic lesions in these arteries. Changes in the proximal segment of the left common carotid artery were the most common finding in diabetic patients, hence attention should be paid to this localization on control examinations.  相似文献   
2.
In this work we present a web-based tool for estimating multiple alignment quality using Bayesian hypothesis testing. The proposed method is very simple, easily implemented and not time consuming with a linear complexity. We evaluated method against a series of different alignments (a set of random and biologically derived alignments) and compared the results with tools based on classical statistical methods (such as sFFT and csFFT). Taking correlation coefficient as an objective criterion of the true quality, we found that Bayesian hypothesis testing performed better on average than the classical methods we tested. This approach may be used independently or as a component of any tool in computational biology which is based on the statistical estimation of alignment quality. AVAILABILITY: http://www.fmi.ch/groups/functional.genomics/tool.htm. SUPPLEMENTARY INFORMATION: Supplementary data are available from http://www.fmi.ch/groups/functional.genomics/tool-Supp.htm.  相似文献   
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4.
The ability to express tightly controlled amounts of endogenous and recombinant proteins in plant cells is an essential tool for research and biotechnology. Here, the inducibility of the soybean heat-shock Gmhsp17.3B promoter was addressed in the moss Physcomitrella patens, using β-glucuronidase (GUS) and an F-actin marker (GFP-talin) as reporter proteins. In stably transformed moss lines, Gmhsp17.3B-driven GUS expression was extremely low at 25 °C. In contrast, a short non-damaging heat-treatment at 38 °C rapidly induced reporter expression over three orders of magnitude, enabling GUS accumulation and the labelling of F-actin cytoskeleton in all cell types and tissues. Induction levels were tightly proportional to the temperature and duration of the heat treatment, allowing fine-tuning of protein expression. Repeated heating/cooling cycles led to the massive GUS accumulation, up to 2.3% of the total soluble proteins. The anti-inflammatory drug acetyl salicylic acid (ASA) and the membrane-fluidiser benzyl alcohol (BA) also induced GUS expression at 25 °C, allowing the production of recombinant proteins without heat-treatment. The Gmhsp17.3B promoter thus provides a reliable versatile conditional promoter for the controlled expression of recombinant proteins in the moss P. patens.  相似文献   
5.
Tomovic A  Oakeley EJ 《PloS one》2008,3(9):e3243

Background

With increasing numbers of crystal structures of protein∶DNA and protein∶protein∶DNA complexes publically available, it is now possible to extract sufficient structural, physical-chemical and thermodynamic parameters to make general observations and predictions about their interactions. In particular, the properties of macromolecular assemblies of multiple proteins bound to DNA have not previously been investigated in detail.

Methodology/Principal Findings

We have performed computational structural analyses on macromolecular assemblies of multiple proteins bound to DNA using a variety of different computational tools: PISA; PROMOTIF; X3DNA; ReadOut; DDNA and DCOMPLEX. Additionally, we have developed and employed an algorithm for approximate collision detection and overlapping volume estimation of two macromolecules. An implementation of this algorithm is available at http://promoterplot.fmi.ch/Collision1/. The results obtained are compared with structural, physical-chemical and thermodynamic parameters from protein∶protein and single protein∶DNA complexes. Many of interface properties of multiple protein∶DNA complexes were found to be very similar to those observed in binary protein∶DNA and protein∶protein complexes. However, the conformational change of the DNA upon protein binding is significantly higher when multiple proteins bind to it than is observed when single proteins bind. The water mediated contacts are less important (found in less quantity) between the interfaces of components in ternary (protein∶protein∶DNA) complexes than in those of binary complexes (protein∶protein and protein∶DNA).The thermodynamic stability of ternary complexes is also higher than in the binary interactions. Greater specificity and affinity of multiple proteins binding to DNA in comparison with binary protein-DNA interactions were observed. However, protein-protein binding affinities are stronger in complexes without the presence of DNA.

Conclusions/Significance

Our results indicate that the interface properties: interface area; number of interface residues/atoms and hydrogen bonds; and the distribution of interface residues, hydrogen bonds, van der Walls contacts and secondary structure motifs are independent of whether or not a protein is in a binary or ternary complex with DNA. However, changes in the shape of the DNA reduce the off-rate of the proteins which greatly enhances the stability and specificity of ternary complexes compared to binary ones.  相似文献   
6.
The content of hypericins (hypericin and pseudohypericin), hyperforin, and flavonoids (rutin, hyperoside, quercitrin, and quercetin) and genetic profiles of eight accessions of Hypericum perforatum L., collected from different locations in India, have been determined. The secondary metabolite content was determined using a highly selective LC/MS/MS method. Pearson and Spearman's correlation coefficient were used to investigate the relationships between the secondary metabolites and a significant positive correlation was found between hypericin and pseudohypericin contents. Genetic profiling was undertaken using the random amplification of polymorphic DNA (RAPD) and single sequence repeat (SSR) methods. Among the 49 random primers used for the initial screening, only nine yielded polymorphic RAPD profiles. The SSR analysis shows that seven out of the 11 primers were polymorphic. There exists only a partial correlation between the chemical content and genetic profiling data among the accessions under study.  相似文献   
7.
The mutagenic effects of low doses of radiation on occupationally exposed subjects were studied on lymphocyte culture using two methods: analysis of structural chromosome aberrations and micronucleus assay. The results obtained in subjects exposed to ionising radiation alone were compared to those exposed to both ionising radiation and ultrasound. A correlation between the total number of chromosome aberrations and distribution of micronuclei in the genome of somatic cells show higher deviation in the group exposed to X-ray and ultrasound than in the group exposed to X-rays alone. The degree of genome damage in occupational exposure to X-rays and ultrasound were discussed.  相似文献   
8.
Summary The archipelago opposite Senj (Croatian Coast) is very exposed to the Bora hurricanes accompanied by air dryness, salt spray, and periodic coast icing. Therefore the xerohalophytic flora of this area is very interesting. Four new taxa from there are described:Astragalus glacialis n. spec. subsp.glacialis s. s. and subsp.uraganicus n. subsp.,Allium horvatii n. spec., andPinus nigra Arn. subsp.croatica n. subsp., a stenoendemic relict near extinction on the isle of Prvi.  相似文献   
9.
Chronic obstructive pulmonary disease (COPD) is a complex disease influenced by genetic and environmental factors. Cystic fibrosis transmembrane conductance regulator (CFTR) protein is an important component of the lung tissue homeostasis, involved in the regulation of the rate of mucociliary clearance. As it is known that certain CFTR variants have consequences on the function of CFTR protein, the aim of this study was to examine the possible role of F508del, M470V, Tn locus, and R75Q variants in COPD development and modulation. Total number of 86 COPD patients and 102 control subjects were included in the study. Possible association between COPD susceptibility, severity, and onset of the disease and allele or genotype of four analyzed CFTR variants was examined. No associations were detected between COPD development, onset of the disease and tested CFTR alleles and genotypes. However, VV470 genotype was associated with mild/moderate COPD stages in comparison to severe/very severe ones (OR = 0.29, 95%CI = 0.11-0.80, p = 0.016). Our study showed that patients with VV470 genotype had a 3.4-fold decreased risk for the appearance of severe/very severe COPD symptoms, and the obtained results indicate that this genotype may have a protective role. These results also suggest the importance of studying CFTR gene as a modifier of this disease.  相似文献   
10.
How do plants feel the heat?   总被引:4,自引:0,他引:4  
In plants, the heat stress response (HSR) is highly conserved and involves multiple pathways, regulatory networks and cellular compartments. At least four putative sensors have recently been proposed to trigger the HSR. They include a plasma membrane channel that initiates an inward calcium flux, a histone sensor in the nucleus, and two unfolded protein sensors in the endoplasmic reticulum and the cytosol. Each of these putative sensors is thought to activate a similar set of HSR genes leading to enhanced thermotolerance, but the relationship between the different pathways and their hierarchical order is unclear. In this review, we explore the possible involvement of different thermosensors in the plant response to warming and heat stress.  相似文献   
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