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11.
Complement is one of primary defense mechanisms against intravascular microorganisms and could play a role in the immune response to malignancy and hence its clinical behavior. We evaluated if the sole coding polymorphism of C1qA associates with outcome in patients with breast carcinoma. Genotyping for C1qA[276A/G] was performed in 63 breast cancer subjects with localized tumor and compared with that in 38 breast cancer subjects with metastasis. Established risk factors for clinical outcome were considered and evaluated in multivariable analysis. Breast cancer subjects with heterozygous or homozygous C1qA[276G] genotype had a higher rate of metastasis than subjects with the homozygous C1qA[276A] genotype [hazard ratio (HR) 2.4, 95% confidence interval (CI) 1.1–4.1]. This association was stronger when only metastatic sites associated with hematogenous spread, i.e., to the bone, liver, and brain, were considered (HR 3.5, 95% CI 1.4–5.6) and remained statistically significant after adjustment for the number of positive lymph nodes, estrogen receptor status, and progesterone receptor status. There was no statistical difference in the C1qA[276A/G] allelic distribution between all subjects with breast cancer and controls. These results suggest there could be an association of a single nucleotide polymorphism at position 276 of the C1qA component of complement with breast cancer metastasis to sites linked to hematogenous spread of disease. The C1qA polymorphism associated with decreased distant metastasis has also been correlated with an increased incidence of subcutaneous systemic lupus and C1q deficiencies, suggesting that an altered immune response may play a role in the observed association. Supported in part by National Institute of Health grant R21-CA90822, Friends You Can Count On! grant 1-87093-00, and the Woody and Louise White Cancer Research Fund.  相似文献   
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The carbohydrate chains of the mucins which constitute the jelly coat surrounding the eggs of Rana temporaria were released by alkaline borohydride treatment. Neutral and acidic oligosaccharide-alditols were purified by ion-exchange chromatography and HPLC. From the structural analysis, based upon 1H and 13C-NMR spectroscopy in combination with MALDI-TOF, the following glycan units are proposed. Abbreviations: MALDI-TOF, matrix assisted laser desorption ionization - time of flight; HPLC, high performance liquid chromatography; COSY, correlation spectroscopy; HSQC, heteronuclear single-quantum coherence spectroscopy; HMQC, heteronuclear multiple-quantum coherence spectroscopy; ROESY, rotating-frame overhauser enhancement spectroscopy; Fuc, fucose; Gal, galactose; GlcNAc, N-acetylglucosamine; GalNAc, N-acetylgalactosamine; GalNAc-ol, N-acetylgalactosaminitol; GlcA, glucuronic acid  相似文献   
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Protein Tyrosine Phosphatases (PTPs) are important contributors to vascular cells normal function, by balancing signaling proteins activation exerted by phosphorylating kinases. Type 2 diabetes related insults, such as hyperglycemia, oxidative stress, and insulin resistance disturb the phosphorylation/dephosphorylation equilibrium towards an abnormal augmented phosphorylation of signaling proteins associated with changes in PTPs expression, enzymatic activity and interaction with cellular substrates. We briefly review here: (i) the new findings on receptor and non-receptor PTPs and their role in vascular cells, (ii) several data on oxidation and phosphorylation of these molecules in endothelial and smooth muscle cells, (iii) vascular PTPs intrinsic activity and dysregulation under the insults of diabetic milieu, and (iv) the potential use of PTPs and their inhibitors as therapeutic targets in Type 2 diabetes-associated vascular dysfunction.  相似文献   
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Background  

If the model of the human hand is created with accuracy by respecting the type of motion provided by each articulation and the dimensions of articulated bones, it can function as the real organ providing the same motions. Unfortunately, the human hand is hard to model due to its kinematical chains submitted to motion constraints. On the other hand, if an application does not impose a fine manipulation it is not necessary to create a model as complex as the human hand is. But always the hand model has to perform a certain space of motions in imposed workspace architecture no matter what the practical application does.  相似文献   
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Oligosporidium nov. gen. arachnicolum (Codreanu-B?lcescu, Codreanu and Traciuc, 1978) is one of the more intensively studied microsporidians from an araneid. It develops into parasitophorous vacuoles formed in the oocytes of Xysticus cambridgei from Bucharest, Romania. The uninucleated schizogonic and sporogonic stages multiply through binary fission and the dense bordered sporoblasts give rise to isolated spores.  相似文献   
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Herpes simplex virus (HSV) entry and cell-cell fusion require glycoproteins gD, gH/gL, and gB. We propose that receptor-activated changes to gD cause it to activate gH/gL, which then triggers gB into an active form. We employed a dual split-protein (DSP) assay to monitor the kinetics of HSV glycoprotein-induced cell-cell fusion. This assay measures content mixing between two cells, i.e., fusion, within the same cell population in real time (minutes to hours). Titration experiments suggest that both gD and gH/gL act in a catalytic fashion to trigger gB. In fact, fusion rates are governed by the amount of gB on the cell surface. We then used the DSP assay to focus on mutants in two functional regions (FRs) of gB, FR1 and FR3. FR1 contains the fusion loops (FL1 and FL2), and FR3 encompasses the crown at the trimer top. All FL mutants initiated fusion very slowly, if at all. However, the fusion rates caused by some FL2 mutants increased over time, so that total fusion by 8 h looked much like that of the WT. Two distinct kinetic patterns, “slow and fast,” emerged for mutants in the crown of gB (FR3), again showing differences in initiation and ongoing fusion. Of note are the fusion kinetics of the gB syn mutant (LL871/872AA). Although this mutant was originally included as an ongoing high-rate-of-fusion control, its initiation of fusion is so rapid that it appears to be on a “hair trigger.” Thus, the DSP assay affords a unique way to examine the dynamics of HSV glycoprotein-induced cell fusion.  相似文献   
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Eggs from Amphibia are surrounded by several layers of jelly that are needed for proper fertilization. Jelly coat is composed of highly glycosylated mucin-type glycoproteins containing up to 60% of carbohydrates, which display a remarkable species-specificity. This material obtained from Triturus alpestris was submitted to reductive beta-elimination and the released oligosaccharide-alditols were further fractionated by HPLC. Structural characterization was performed through a combination of two dimensional (1)H-(1)H and (1)H-(13)C NMR and ESI-MS/MS analysis. Numerous carbohydrate chains are characterized by the presence of the Cad (Sd(a)) determinant, including respectively NeuAc, NeuGc or Kdn as a sialic acid. But the most significant O-glycan sequences which mark the difference between the jelly of T. alpestris and other studies amphibian jellies are polymers of GalNAc(beta 1-4)GlcNAc (LacdiNAc) which form part of the following sequence: HSO(3)(4)(GalNAcbeta 1-4GlcNAcbeta 1-3)(1-3)GalNAcbeta 1-4(GlcNAcbeta 1-3)(0-1)GlcNAcbeta 1-6GalNAc-ol.  相似文献   
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