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81.
82.
Recently, genome-wide association studies have identified and validated genetic variations associated with urinary bladder cancer (UBC). However, it is still unknown whether the high-risk alleles of several SNPs interact with one another, leading to an even higher disease risk. Additionally, there is no information available on how the UBC risk due to these SNPs compare to the risk of cigarette smoking and to occupational exposure to urinary bladder carcinogens, and whether the same or different SNP combinations are relevant in smokers and non-smokers. To address these questions, we analyzed the genotypes of six SNPs, previously found to be associated with UBC, together with the GSTM1 deletion, in 1,595 UBC cases and 1,760 controls, stratified for smoking habits. We identified the strongest interactions of different orders and tested the stability of their effect by bootstrapping. We found that different SNP combinations were relevant in smokers and non-smokers. In smokers, polymorphisms involved in detoxification of cigarette smoke carcinogens were most relevant (GSTM1, rs11892031), in contrast to those in non-smokers with MYC and APOBEC3A near polymorphisms (rs9642880, rs1014971) being the most influential. Stable combinations of up to three high-risk alleles resulted in higher odds ratios (OR) than the individual SNPs, although the interaction effect was less than additive. The highest stable combination effects resulted in an OR of about 2.0, which is still lower than the ORs of cigarette smoking (here, current smokers'' OR: 3.28) and comparable to occupational carcinogen exposure risks which, depending on the workplace, show mostly ORs up to 2.0.  相似文献   
83.
The development of heart failure (HF) is characterized by progressive alteration of left ventricle structure and function. Previous works on proteomic analysis in cardiac tissue from patients with HF remain scant. The purpose of our study was to use a proteomic approach to investigate variations in protein expression of left ventricle tissue from patients with ischaemic (ICM) and dilated cardiomyopathy (DCM). Twenty-four explanted human hearts, 12 from patients with ICM and 12 with DCM undergoing cardiac transplantation and six non-diseased donor hearts (CNT) were analysed by 2DE. Proteins of interest were identified by mass spectrometry and validated by Western blotting and immunofluorescence. We encountered 35 differentially regulated spots in the comparison CNT versus ICM, 33 in CNT versus DCM, and 34 in ICM versus DCM. We identified glyceraldehyde 3-phophate dehydrogenase up-regulation in both ICM and DCM, and alpha-crystallin B down-regulation in both ICM and DCM. Heat shock 70 protein 1 was up-regulated only in ICM. Ten of the eleven differentially regulated proteins common to both aetiologies are interconnected as a part of a same network. In summary, we have shown by proteomics analysis that HF is associated with changes in proteins involved in the cellular stress response, respiratory chain and cardiac metabolism. Although we found altered expression of eleven proteins common to both ischaemic and dilated aetiology, we also observed different proteins altered in both groups. Furthermore, we obtained that seven of these eleven proteins are involved in cell death and apoptosis processes, and therefore in HF progression.  相似文献   
84.
Recently, EDI3 was identified as a key factor for choline metabolism that controls tumor cell migration and is associated with metastasis in endometrial carcinomas. EDI3 cleaves glycerophosphocholine (GPC) to form choline and glycerol-3-phosphate (G3P). Choline is then further metabolized to phosphatidylcholine (PtdC), the major lipid in membranes and a key player in membrane-mediated cell signaling. The second product, G3P, is a precursor molecule for several lipids with central roles in signaling, for example lysophosphatidic acid (LPA), phosphatidic acid (PA) and diacylglycerol (DAG). LPA activates intracellular signaling pathways by binding to specific LPA receptors, including membrane-bound G protein-coupled receptors and the intracellular nuclear receptor, PPARγ. Conversely, PA and DAG mediate signaling by acting as lipid anchors that bind and activate several signaling proteins. For example, binding of GTPases and PKC to PA and DAG, respectively, increases the activation of signaling networks, mediating processes such as migration, adhesion, proliferation or anti-apoptosis—all relevant for tumor development. We present a concept by which EDI3 either directly generates signaling molecules or provides “membrane anchors” for downstream signaling factors. As a result, EDI3 links choline metabolism to signaling activities resulting in a more malignant phenotype.  相似文献   
85.

Background

Speciose clades usually harbor species with a broad spectrum of adaptive strategies and complex distribution patterns, and thus constitute ideal systems to disentangle biotic and abiotic causes underlying species diversification. The delimitation of such study systems to test evolutionary hypotheses is difficult because they often rely on artificial genus concepts as starting points. One of the most prominent examples is the bellflower genus Campanula with some 420 species, but up to 600 species when including all lineages to which Campanula is paraphyletic. We generated a large alignment of petD group II intron sequences to include more than 70% of described species as a reference. By comparison with partial data sets we could then assess the impact of selective taxon sampling strategies on phylogenetic reconstruction and subsequent evolutionary conclusions.

Methodology/Principal Findings

Phylogenetic analyses based on maximum parsimony (PAUP, PRAP), Bayesian inference (MrBayes), and maximum likelihood (RAxML) were first carried out on the large reference data set (D680). Parameters including tree topology, branch support, and age estimates, were then compared to those obtained from smaller data sets resulting from “classification-guided” (D088) and “phylogeny-guided sampling” (D101). Analyses of D088 failed to fully recover the phylogenetic diversity in Campanula, whereas D101 inferred significantly different branch support and age estimates.

Conclusions/Significance

A short genomic region with high phylogenetic utility allowed us to easily generate a comprehensive phylogenetic framework for the speciose Campanula clade. Our approach recovered 17 well-supported and circumscribed sub-lineages. Knowing these will be instrumental for developing more specific evolutionary hypotheses and guide future research, we highlight the predictive value of a mass taxon-sampling strategy as a first essential step towards illuminating the detailed evolutionary history of diverse clades.  相似文献   
86.
Tumor invasion into blood and/or lymphatic channels is an important component of cancer staging and prognosis. Standard pathological methods do not provide sufficient contrast to discriminate between invasion into each type of vessel and are complicated by tissue retraction artifacts. We evaluated the ability of a triple-stain immunohistochemical method, combining cytokeratin, CD34, and podoplanin stains in a single section, to distinguish blood from lymphatic vascular invasion in oral squamous cell carcinoma and confirmed its results using multispectral analysis. The triple-stain method was significantly more sensitive in detecting invasive events than the standard hematoxylin and eosin staining method and easily discriminated between blood and lymphatic vessel invasion. Invasive events were present in blood and/or lymphatic vessels in the majority of patients with and without presentation of lymph node metastasis, indicating that vessel invasion in this cancer model is common and is not a rate-limiting step for lymph node metastasis.  相似文献   
87.
We describe compounds in which an emollient or a humectant bears an α,β-unsaturated thiol ester capable of reacting with nucleophilic amino acids in stratum corneum proteins. These compounds should serve as long-lasting moisturizers for skin. The emollient derivatized was octadecyl propanoate, and the humectant was poly(ethylene glycol). These hydrophobic and hydrophilic compounds, as well as a fluorescent, dansyl-containing thiol ester, were found to react within minutes with the thiol N-acetylcysteamine upon addition of a catalytic amount of an organic base in chloroform. The structures of the products resulting from conjugate addition to the unsaturated thiol esters were determined by NMR spectroscopy. In the case of the α,β,γ,δ-unsaturated (sorboyl) thiol ester, both the 1,4-addition product and the β,γ-unsaturated-1,6-addition product formed, followed by diadduct. An in vivo test of the fluorescent α,β-unsaturated thiol ester showed that this compound persisted on skin for 3 weeks vs. 6 days for the non-bonding control compound.  相似文献   
88.
Transient expression of engineered reporter RNAs encoding an intron-containing green fluorescent protein (GFP) from a Potato virus X-based expression vector previously demonstrated the nuclear targeting capability of the 359 nucleotide Potato spindle tuber viroid (PSTVd) RNA genome. To further delimit the putative nuclear-targeting signal, PSTVd subgenomic fragments were embedded within the intron, and recombinant reporter RNAs were inoculated onto Nicotiana benthamiana plants. Appearance of green fluorescence in leaf tissue inoculated with PSTVd-fragment-containing constructs indicated shuttling of the RNA into the nucleus by fragments as short as 80 nucleotides in length. Plant-to-plant variation in the timing of intron removal and subsequent GFP fluorescence was observed; however, earliest and most abundant GFP expression was obtained with constructs containing the conserved hairpin I palindrome structure and embedded upper central conserved region. Our results suggest that this conserved sequence and/or the stem-loop structure it forms is sufficient for import of PSTVd into the nucleus.  相似文献   
89.
Summary A new section through Cretaceous deposits was discovered 1 km west of the Dizlu village (approximately 40 km north of Esfahan, central Iran). Lithologically, the section distinctly differs from all other sections exposed in neighboring localities. A scleractinian coral fauna (Upper Aptian-Upper Albian), collected from a reefal limestone, is described in detail. The following taxa were found:Actinastrea aff.pseudominima (Koby),Columactinastraea sp.,Eugyra cotteaui (d'Orbigny),Pseudomyriophyllia turnsekae Baron-Szabo,Montlivaltia sp.,Paraclausastrea pulchra Morycowa,Placocoenia robusta Oppenheim,Columnocoenia ksiazkiewiczi Morycowa,Stylina micropora Koby,Felixigyra deangelisi Prever,Cyathophora haysensis Wells,Diploastraea harrisi Wells,Morphastrea cf.ludovicina (Michelin),Meandrophyllia meandroides (Koby),Eocomoseris raueni L?ser,Fungiastrea crespoi (Felix),Latiastraea cf.kaufmanni (Koby),Kobya aff.crassolamellosa Gregory. The coral association of the Esfahan region is dominated by forms that are known to be cosmopolitan and semicosmopolitan in the Lower Cretaceous. It was found that over 40% of the coral fauna had previously been reported from both Lower and Upper Cretaceous strata. A similar pattern has been recognized for other reefal associations (e.g. Albian of Greece and Upper Barremian-Middle Albian of Mexico). In contrast, coral assemblages which developed in rather soft bottom environments have a significantly smaller percentage (15–20%) of taxa extending into the Upper Cretaceous and show closer affinities to Upper Jurassic and Lower Cretaceous faunas.  相似文献   
90.
Phosphorylation of solubilized and purified high-affinity (Ca2+ + Mg2+)-ATPase (ATP phosphohydrolase, EC 3.6.1.3) of human erythrocyte membranes shows no dependence on cyclic AMP concentration in the range 0.1–1000 μM.Ca2+-dependent phosphoprotein is sensitive to hydroxylamine and molybdate treatment. The phosphate linkage shows maximum stability at low pH values, which is progressively lost as the pH rises, with a shoulder around pH 6. SDS gel electrophoresis of the phosphorylated protein yields a peak which shows relative mobility corresponding to a molecular weight of 145 000 and sensitivity to MgATP-chase and hydroxylamine treatment. This indicates that the phosphoprotein represents the phosphorylated intermediate of the high-affinity (Ca2+ + Mg2+)-ATPase of human erythrocyte membranes.  相似文献   
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