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To propose an equipment and technology package for oxygen preparation and supply under hypoxia conditions in order to meet the requirements of populations on the plateau .Different populations were analyzed in terms of their oxygen supply requirements, and the modes, schemes and equipment for oxygen supply were explored accordingly and then applied.Efforts in the past 20 years have resulted in the advances in the equipment for centralized, mobile and portable oxygen preparation and supply, though the equipment for individual use hads to be improved and the diffused oxygen supply scheme also needs to be further evaluated .
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Objective To investigate the role of recombinant human interleukin 6 (rhlL-6) in calcification and osteogenic transition of cultured human umbilical artery smooth muscle cells (HUASMC), and the possible cell signal transduction way. Methods HUASMCs were isolated by the explant method. HUASMCs were treated with (treatment groups) or without (control group) rhIL-6. Alizarin Red S stain was applied for calcium deposition in extracellular matrix of control ceils and the cells treated with rhIL-6 50 μg/L at day 12. Calcium concentration in cell layer of control group and treatment group (treated with rhIL-6 10 μg/L and 50 μg/L, respectively) was determined calorimetrically by the o-cresolphthalein complexone method at day 3, 6, 9 and 12, and corrected by total cell proteins. The mRNA expressions of bone-specific alkaline phosphatase (BAP), osteopontin (OPN), bone morphogenetic protein-2 (BMP2) and osteoprotegerin (OPG) were estimated by real-time PCR in 12, 24 and 72 hours. OPN, BMP2 and OPG expressions were assessed by Western blotting and the BAP concentration at the same time was checked by fluorometry method . Electrophoretie mobility shift assays (EMSA) was used to detect the binding activity of transcription factor Cbfα1 with or without inhibitors of p38-MAPK (SB203580) and PKC (DHC) after 6 hours stimulation by rhIL-6 10 μg/L. Results rhIL-6 induced a positive Alizarin Red S stain and a time-dose-dependent increasing of cell layer calcium deposition.Compared with control group, rhIL-6 10 μg/L enhanced gene expression and protein levels of BAP and BMP2 at the early time (12 and 24 hours), and of OPN and OPG at later hours (24 and 72 hours). RhIL-6 still induced an increasing of binding activity of Cbfα1, which could be partially blocked by DHC but not SB203580. Conclusions rhIL-6 induces HUASMCs calcification and osteogenie transition in vitro, which may be one of the mechanism involved in IL-6 associated vascular calcification as observed in clinical studies. The role of IL-6 in HUASMCs may partially achieved through the PKC cell signal transduction way.
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Objective To study the effect of uremic serum on the calcification and osteogenic transition of cultured human umhilical artery smooth muscle cells(HUASMC).Methods Sera from 40 healthy controls(control group),40 nondialysis uremic patients(nondialysis group)and 45 uremic patients on dialysis(dialysis group)were detected fi)r biochemical indexes concerned and used to treat the cultured HUASMC.Alizarin red S stain was applied to examined calcium deposition in the cell layer.Calcium concentration was determined calorimetrically by the Ocresolphtha]ein complexone method,and corrected by total cell proteins.The mRNA expression of bone specific alkaline phosphatase(BAP),osteopontin(OPN)and bone morphogenelic protein 2(BMP2)was estimated by realtime PCR.OPN and BMP2 protein expression was assessed by Western blotting and fluorometry method was used to check the BAP concentration. Results Serum biochemical detection revealed thai both uremic groups had higher levels of phosphate,triglyseride,iPTH,C-reactive protein(CRP)and IL-6,and lower level of fetuin-A than healthy control(P＜0.05).Furthermore,dialysis serum had higher levels of triglyseride,CRP and IL-6 than nondialysis serum(P＜0.05).Compared with control group,both uremic scra induced more cell layer calcium deposition and higher mRNA and protein expression levels of BMP2,BAP and OPN(P＜0.05).Higher mRNA and protein expression levels of above factors were found in dialysis group as compared to nondialysis group(P＜0.05). Conclusions Uremic serum can induce HUASMC calcification and osteogenic transition in vitro,which may be one of the mechanisms involved in vascular calcification of ESRD patients.Microinflammatory state may promote the osteogenic transition and vascular calcification in dialysis patients.
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ObjectiveTo investigate the effects of pravastation intervention on tumor necrosis factor (TNF)-α-indueed ossifie calcification in human umbilical artery smooth muscle cells (hUASMCs). MethodshUASMCs were cultured by tissue explant in vitro, hUASMC were treated with TNF-α 50 μg/L and pravastatin of three different concentrations. The calcium deposition was determined by O-cresolphthalein eomplexone method. The mRNA expression of BAP and OPN was determined by real time-PCR. The protein expression of BAP, OPN and BMP-2 was determined by Western blotting. ResultsPravastatin inhibited the proliferation of hUASMC (r=-0.946, P＜0.01) and decreased the cell calcium deposition (r=-0.973, P＜0.01) in a dosedependent manner. Pravastatin down-regulated the expression of BAP, OPN and BMP-2 induced by TNF-α in a dose-dependent manner (mRNA, r=-0.972, P＜0.01;BAP protein, r=-0.820, P＜0.01;OPN protein, r=-0.972, P＜0.01;BMP-2 protein, r=-0.928, P＜0.01). ConclusionPravastatin can inhibit the proliferation of hUASMC, decrease the cell calcium deposition and inhibit the ossifie calcification of hUASMC induced by TNF-α.