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Objective To study the effect of mitogen-activated protein kinas/extracellular signalregulated kinase (MAPK/ERK) signaling pathway on cell proliferation modulated by Sonic Hedgehog (Shh) signaling in fibroblast-like synoviocytes (FLS) isolated from patients with active rheumatoid arthritis (RA).Methods The synovial tissue were collected by the synovial arthroscopic debridement or arthroscopic synovectomy of RA patients with active disease activity [disease activity score(DAS)28 ≥3.2].The RA-FLS were primarily cultured by the explanted culture,and then were treated with Shh agonist purmorphamine,inhibitor cyclopamine or MAPK/ERK signaling pathway inhibitor U0126,respectively.Western blotting was used to examine the phosphorylation level of ERK 1/2 (p-ERK1/2),which was the critical protein of MAPK/ERK signaling.The cell proliferation activity was detected using cell proliferation and cytotoxicity kit-8 (CCK8),and the cell proliferation rate was detected using a flow cytometry.Analysis of variance and Kruskal-Wallis H(K) test were used for statistical analysis.Results Compared with the control group,purmorphamine transiently increased p-ERK1/2 protein at the concentration of 1 μmol/L,and the peak activations of p-ERK1/2 took place at 15 min (P＜0.01).Cyclopamine and U0126 decreased the expression ofp-ERK1/2 protein (P＜0.01).After the RA-FLS treated with purmorphmine(1 μmol/L)for 48 hours,the cell proliferation activity was (114±4)％ and the percentage of S phase cells was (8.39±0.60)％,which was significantly higher than those of the control group (100±0)％ (P＜0.01) and (3.29±0.69)％ (P＜0.01).After treated with cyclopamine (10 μmol/L) for 48 hours,the cell proliferation activity of RA-FLS was (89±1)％ (P＜0.05) and the percentage of S phase cells was (1.53±0.22)％ (P＜0.05).When co-treated with purmorphamine (1 μmol/L) and U0126 (10 μmol/L),the cell proliferative activity was (89±2)％ (P＜0.05) and the percentage of S phase cells was(1.07±0.25)％(P＜ 0.05).Conclusion Shh may promote proliferation of RA-FLS via modulating MAPK/ERK signaling,which in turn contributes to hyperplasia of synovium and ultimately leading to RA.
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Objective To explore the feasibility of team-based learning (TBL) for practice teaching of internal medicine.Methods TBL was carried out in 40 interns from clinical medical students of eight-year program.Every team included 4 ～ 5 members.The course of rheumatoid arthritis was chosen according to the course syllabus.Results The students discussed enthusiastically in the team test and in-class application exercises.More than 80％ of the students expressed that TBL was helpful to understand the course content better,to learn the disease better,to elevate personal study ability and to know others' thought processes.76％ of the students supported to carrry out TBL again.Conclusions TBL is helpful for senior medical students to elevate their ability of applying course concepts to solve practical problems through a series of team activities.Improvement of teaching idea and skill is the key to perform TBL successfully.
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Objective To investigate the effect of tumor necrosis factor (TNF)-α antagonists on liver function and reactivation of hepatitis B virus ( HBV ) in patients with inflammatory arthropathy with concurrent chronic HBV infection.Methods Patients with active rheumatoid arthritis (RA) and ankylosing spondylitis (AS) who were grouped according to serum HBV biomarkers were treated with TNF-α antagonist.The liver function and reactivation of HBV were monitored before and after anti-TNF-α therapy.Kruskal-Wallis one-way analysis of variance on ranks of continuous variables and x2 test or Fisher's exact test for categorical variables among 3 or more groups.Results Fifty patients were enrolled with 3 to 23 months of follow-up visit.The level of transaminases in chronic HBV infection group [n=11,AST (36±18) U/L,ALT (44±46) U/L] were significantly higher than that in past HBV exposure group [n=16,AST (22±6) U/L,ALT (17±9) U/L] or free of HBV infection group [n=23,AST (19±6) U/L,ALT (15±9) U/L](AST:x2=11.161,P＜0.01,ALT:x2=8.038,P＜0.01).One patient with elevated baseline HBV-DNA load was treated concomitantly with lamivudine and anti-TNF-α therapy,and the HBV-DNA load reduced about to normal 4 months later.Among the other 10 patients with normal baseline HBV-DNA load in chronic HBV infection group,one patient showed reactivation of HBV with elevated transaminases after anti-TNF-α therapy; another patient had only elevated transaminases without reactivation of HBV,and the transaminases returned to normal after withdrawal of antiTNF-α therapy,which suggested drug-induced liver injury.All patients in both past HBV exposure group and free of HBV infection group remained HBsAg negative after the therapy.Conclusion Patients with inflammatory arthropathy should be screened for HBV infection and check liver function before anti-TNF-α therapy,and carefully monitor the reactivation of HBV and liver function during treatment.Patients with concurrent chronic HBV infection should be treated conco-mitantly with anti-virus and anti-TNF-α therapy if they have elevated baseline HBV-DNA load (＞105 copies/ml,in particular) and good economic situation.
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ObjectivesTo examine the validity of high-frequency Doppler ultrasound in identifying knees synovitis in patients with rheumatoid arthritis(RA).MethodsNinety-five consecutive patients with active RA were examined withhigh-frequency Doppler ultrasound to examine synovitis signals in knees.Synovial tissue samples of 51 patients were obtained by closed needle biopsy from knees after ultrasound examination.Serial synovial tissue sections were stained with H&E and immunohistochemical staining,and the histopathological synovitis scores were evaluated.The relationship among clinical, histopathological and ultrasound synovitis indexes was analyzed by Spearman's rank order correlation test and receiver operating characteristic curve analysis.ResultsAmong 95 RA patients,the median thickness of synovial membrane in ultrasound was 2.8 mm,the median depth of effusion was 2.7 mm; Doppler signals of synovial blood flow were detected in 82％(78/95 ) of patients and the median semiquantitive grading of synovial blood flow was 1.0.The thickness of synovial membrane and synovial blood flow at Doppler ultrasound correlated positively with histological synovitis score,hyperplasia of the lining layer,and inflammatory infiltration in sublining area (the thickness of synovial membrane:r=0.438,0.424,0.368,respectively; synovial blood flow:r=0.357,0.377,0.347,respectively; all P＜0.05).Although there was no significant difference in clinical synovitis indexes between patients with histologically low-grade and high-grade synovitis,the thickness of synovial membrane and synovial blood flow in ultrasound in patients with histologically high-grade synovitis was significantly higher than those with low-grade synovitis(P=0.001,0.036,respectively).When the thickness of synovial membrane in ultrasound was ≥ 3.9 mm,the specificity of diagnosing the high-grade synovitis was 96.7％ and the sensitivity was 61.9％.ConclusionSynovitis signals at high-frequency Doppler ultrasound correlate with histopathological synovitis,and it might be helpful in evaluating the severity of histopathological synovitis.
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ObjectiveTo investigate the effect of rosiglitazone (RSG), a high-affinity synthetic agonist for PPAR-γ, on the expression of receptor activator of NF-κB ligand (RANKL) and osteoprotegerin (OPG)in rheumatoid arthritis fibroblast-like synoviocyte (RA-FLS) and the underlying mechanisms. MethodsRAFLS were incubated with different concentrations of RSG(0, 5, 10, 15, and 20 μmol/L) for 3 days, RAFLS proliferation was detected by Cell Counting Kit-8 assay, and then the expression of RANKL and OPG was examined by real-time PCR and Western blot. The expression of phosphorylated ERK, p38 and JNK was also detected after RA-FLS was incubated with RSG(0, 15, and 20 μmol/L) for 3 days. One-way ANOVA and Bonferroni were used for statistical analysis. ResultsRSG (5, 10, 15, and 20 μmol/L) had significantly inhibited the expression of RANKL mRNA(0.503±0.005, 0.438±0.031, 0.161±0.042, 0.050±0.018) and protein (1.72±0.09, 1.58x±0.05, 1.46±0.11, 1.22x±0.14) in RA-FLS (F=200.820, F=13.602, P＜0.01 ), while the expression of OPG mRNA (2.8 ±0.5, 7.0 ±3.2, 8.4 ±2.3, 25.7 ±5.1 ) and protein ( 1.21 ±0.11, 1.52 ±0.16, 1.63±0.11, 1.91 ±0.03) increased significantly (F=26.531, F=24.872, P＜0.01), both in a dose dependent manner. The ratio of RANKL/OPG mRNA and protein significantly reduced (F=453.425, P＜0.01 ;F=4.173, P＜0.05 ). RSG (15, 20 μ mol/L) significantly inhibited the expression of p-ERK-1/2 protein (0.55±0.06, 0.45±0.06, F=6.991, P＜0.05). ConclusionRSG can inhibit RANKL expression in RA-FLS through p-ERK pathway.
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Objective To investigate the effect of hypoxia-inducible factor (HIF)-1α and vascular en-dothelial growth factor (VEGF) on the angioge-nesis of rheumatoid arthritis (RA). Methods The collagen-induced arthritis (CIA) model was set up in male Wistar rats. The pathological angiogenesis and expression of HIF-1α and VEGF in the synovia different time points were observed by H&E and immunohistochemistry staining. Results The expressions of HIF-1α and VEGF on CIA synovium were significantly elevated and their expression increased gradually with the prolonged disease course. Both synovial HIF-1α expression and VEGF expression were correlated significantly with the pathological angiogenesis score. Synovial lining and sublining HIF-1α expression were correlated significantly with VEGF expression respectively. Conclusion H1F-1α may play an important role in the pathogenesis of RA by upregulating the expression of VEGF and then promoting angiogenesis.
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Objective To explore the protective effects of geranylgeranylacetone (GGA) on acute renal failure tats induced by isehemia reperfusion (IR) and the possible mechanism. Methods GGA (400 mg/kg) was administered to induce overexpression of heat shock protein 72 (HSP72) in the kidney of Sprague-Dawley (SD) rats. IR model was generated by temporary clamping the left renal artery for 45 minutes followed by right nephrectomy and 24 h reperfusion. A sham-operated group was used as normal control. 24 h after reperfnsion, rats were sacrificed. Blood was collected for measurement of serum creatinine (Scr) and blood urea nitrogen ( BUN ). Paraffin-embedded sections of the kidney were stained with PAS. Histological changes due to tubular damage were quantitated as tubular damage score. TUNEL assay was used to detect the apoptosis, and Western-blot was used to detect the expression of XIAP. Results After renal IR, the increased level of BUN and Scr, the tubular injury and the apoptosis of renal tubular epithelial cells were observed (P＜0.01). At the same time, the decreased level of XIAP was observed (P＜ 0.01). Compared with the control groups, the level of HSP72 expression was up-regulated in oral administration of GGA group (P＜0.05). The expression levels of BUN and serum creatinine were significantly decreased after IR injury in pre-conditioned rats with over-expression of HSP72 (P＜ 0.01 ). Kidney morphology was better preserved in GGA group. Rats with over-expression of HSP72 also revealed reduction of apoptotic cells by TUNEL stain and XIAP degradation by Western blot (P＜0.05). Conclusion GGA attenuates renal IR injury at least in part through inhibiting tubular cell apoptosis by decreasing XAIP degradation and restoring XIAP protein level.