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11.
CD study of four modified nucleosides, constituents of tRNA molecules, revealed that 2-thio-5-methyluridine and 5-methyluridine in aqueous solution, 0.1N HCl, and organic solvents essentially occur in an anti-conformation. 5-Methylcytidine also occurs in an anti-conformation similar to cytidine in aqueous solution and organic solvents, while 2-thiocytidine dihydrate appears to occur in an anti-conformation. It is stressed that the CD data of thionucleosides might be applied to the successfully conformational analysis of tRNA molecules. 相似文献
12.
Impaired elastin fiber assembly is observed in the fetal ductus arteriosus (DA), associated with a reduced concentration of elastin binding protein (EBP), a 67-kDa galactolectin. It is also seen in cultured aortic (Ao) smooth muscle cells (SMC) following the release of the EBP by glycosaminoglycans rich in AN-acetylgalactosamine, such as chondroitin sulfate (CS). In the DA, impaired elastin fiber assembly is observed in conjunction with intimal thickening associated with increased migration of SMC into the subendothelium, a feature we previously related to increased production of fibronectin. In this report, we determined whether SMC use the EBP to attach to an elastin substrate, whether shedding of the EBP promotes SMC migration through a threedimensional network of pure elastic laminae prepared from sheep aorta, and whether the latter is associated with increased production of fibronectin. We observed reduced attachment to elastin-coated surfaces of DA SMC deficient in EBP compared to Ao SMC. Addition of CS but not heparan sulfate (a glycosaminoglycan which does not induce EBP shedding) decreased Ao SMC attachment to elastin, as did preincubation with VGVAPG elastin-derived peptides which saturate the EBP. The immunolocalization of cell surface EBP suggested that cells can quickly replace EBP released from their surfaces by CS treatment. The magnitude of CS-induced impaired attachment of SMC to elastin was dose dependent and could be further increased by the administration of cyclohexamide and sodium azide. Also, the reversibility of CS-induced detachment was prevented by monensin. This suggests that a process of new synthesis and intracellular transport of the EBP was necessary to replace the EBP molecules released from the cell surface by CS treatment. In the migration assay, both DA and Ao SMC attached to the top of an elastin membrane, but only DA SMC deficient in EBP migrated through the laminae. Addition of CS, which induced shedding of EBP, resulted in Ao SMC migration associated with increased synthesis of fibronectin. We postulate that CS-induced release of EBP from SMC surfaces causes cell detachment from elastin and an increase in fibronectin synthesis, processes which may be critical in promoting SMC migration associated with intimal thickening developmentally in the DA and perhaps also in vascular disease. 相似文献
13.
The amino acid and muropeptide compositions of murein (peptidoglycan) isolated from populations of Caulobacter crescentus predominantly composed of swarmer or stalked cells were determined and compared with the structure of murein sacculi obtained from a population of unsegregated cells. It appears that in spite of vast morphological alterations in the course of the cell cycle, the murein composition of the various cell types is not markedly different. 相似文献
14.
Otylia Kowal-Bielecka Marek Bielecki Serena Guiducci Beata Trzcinska-Butkiewicz Ma?gorzata Michalska-Jakubus Marco Matucci-Cerinic Marek Brzosko Dorota Krasowska Lech Chyczewski Krzysztof Kowal 《Arthritis research & therapy》2013,15(3):R69
Introduction
Systemic sclerosis (SSc) is an autoimmune disease characterized by chronic inflammation, vascular injury and excessive fibrosis. CD163 is a scavenger receptor which affects inflammatory response and may contribute to connective tissue remodelling. It has recently been demonstrated that CD163 can bind and neutralize the TNF-like weak inducer of apoptosis (TWEAK), a multifunctional cytokine which regulates inflammation, angiogenesis and tissue remodelling. We aimed to investigate the relationships between serum levels of soluble CD163 (sCD163) and soluble TWEAK (sTWEAK) in relation to disease manifestations in SSc patients.Methods
This study included 89 patients with SSc who had not received immunosuppressive drugs or steroids for at least 6 months and 48 age- and sex-matched healthy controls (HC) from four European centres. Serum concentrations of sTWEAK and sCD163 were measured using commercially available ELISA kits.Results
The mean serum concentrations of sTWEAK were comparable between SSc patients (mean +/- SD: 270 +/- 171 pg/mL) and HC (294 +/- 147pg/mL, P >0.05). Concentration of sCD163 and sCD163/sTWEAK ratio were significantly greater in SSc patients (984 +/- 420 ng/mL and 4837 +/- 3103, respectively) as compared to HC (823 +/- 331 ng/mL and 3115 +/- 1346 respectively, P <0.05 for both). High sCD163 levels and a high sCD163/sTWEAK ratio (defined as > mean +2SD of HC) were both associated with a lower risk of digital ulcers in SSc patients (OR, 95%CI: 0.09; 0.01, 0.71, and 0.17; 0.06, 0.51, respectively). Accordingly, patients without digital ulcers had a significantly higher sCD163 concentration and sCD163/sTWEAK ratio as compared to SSc patients with digital ulcers (P <0.01 for both) and HC (P <0.05 for both). A high sCD163/sTWEAK ratio, but not high sCD163 levels, was associated with greater skin involvement.Conclusions
The results of our study indicate that CD163-TWEAK interactions might play a role in the pathogenesis of SSc and that CD163 may protect against the development of digital ulcers in SSc. Further studies are required to reveal whether targeting of the CD163-TWEAK pathway might be a potential strategy for treating vascular disease and/or skin fibrosis in SSc. 相似文献15.
16.
Hinzpeter A Fritsch J Borot F Trudel S Vieu DL Brouillard F Baudouin-Legros M Clain J Edelman A Ollero M 《The Journal of biological chemistry》2007,282(4):2423-2432
ClC-2 is a broadly expressed member of the voltage-gated ClC chloride channel family. In this study, we aimed to evaluate the role of the membrane lipid environment in ClC-2 function, and in particular the effect of cholesterol and ClC-2 distribution in membrane microdomains. Detergent-resistant and detergent-soluble microdomains (DSM) were isolated from stably transfected HEK293 cells by a discontinuous OptiPrep gradient. ClC-2 was found concentrated in detergent-insoluble membranes in basal conditions and relocalized to DSM upon cholesterol depletion by methyl-beta-cyclodextrin. As assessed by patch clamp recordings, relocalization was accompanied by acceleration of the activation kinetics of the channel. A similar distribution and activation pattern were obtained when cells were treated with the oxidant tert-butyl hydroperoxide and after ATP depletion. In both cases activation was prevented by cholesterol enrichment of cells. We conclude that the cholesterol environment regulates ClC-2 activity, and we provide evidence that the increase in ClC-2 activity in response to acute oxidative or metabolic stress involves relocalization of this channel to DSM. 相似文献
17.
Akunevich Anastasia Aleksandrovna Khrustalev Vladislav Victorovich Khrustaleva Tatyana Aleksandrovna Poboinev Victor Vitoldovich Shalygo Nikolai Vladimirovich Stojarov Aleksander Nicolaevich Arutyunyan Alexander Migranovich Kordyukova Larisa Valentinovna Sapon Yehor Gennadyevich 《The protein journal》2022,41(2):245-259
The Protein Journal - An interplay between monomeric and dimeric forms of human epidermal growth factor (EGF) affecting its interaction with EGF receptor (EGFR) is poorly understood. While EGF... 相似文献
18.
Pant Sanjay Sizarov Aleksander Knepper Angela Gossard Gatan Noferi Alberto Boudjemline Younes Vignon-Clementel Irene 《Biomechanics and modeling in mechanobiology》2022,21(2):471-511
Biomechanics and Modeling in Mechanobiology - Potts shunt (PS) was suggested as palliation for patients with suprasystemic pulmonary arterial hypertension (PAH) and right ventricular (RV) failure.... 相似文献
19.
Michal Lorenz Brygida Bisikirska Beata Hanus-Lorenz Kazimierz Strzalka Aleksander F. Sikorski 《Cell biology international》1995,19(7):625-632
It was found either in Western-blot analysis or in indirect immunofluorescence microscopy that cells of the alga Chlamydomonas reinhardtii contain polypeptides cross-reacting with antibodies directed against red blood cell spectrin. The protein could also be detected by immunoprecipitation with anti-spectrin antibodies. C. reinhardtii cells contain distinct polypeptide chains reacting with antibodies directed against either α- or β-spectrin subunits. This protein was extracted from the cells with low ionic strength solution but was not with nonionic detergent. 相似文献
20.