Objective To investigate the effects and partial mechanism of prednisone and TACI-Ig combination on MRL/Mpslac-lpr ( MRL/lpr) mice. Methods MRL/lpr mice were randomly divided into 6 groups, which includ-ed model group, prednisone (2. 5, 5. 0 mg/kg) group, TACI-Ig (15. 0 mg/kg) group, prednisone and TACI-Ig combination [(2. 5+7. 5) mg/kg, (2. 5+15. 0) mg/kg] group. BALB/c mice were set as normal group. Pred-nisone was given intragastrically everyday and TACI-Ig was given subcutaneously every two days for 13 weeks. In the meantime, the normal and model group were treated with an equal volume of normal saline. The general sign and proteinuria level were observed in the treatment period. The sections of spleen and kidney tissues for pathologi-cal analysis were stained with HE. Serum levels of auto-antibodies and BAFF were detected by ELISA kit. The per-centage of plasma cells and CD138 expression in the spleen were detected by flow cytometry analysis and immuno-histochemistry, respectively. Results The skin damage and the proteinuria level were improved and decreased by prednisone and TACI-Ig combination treatment. The spleen and kidney pathology were also improved including re-ducing germinal center formation and alleviating the glomerular fibrosis, mesangial cell hyperplasia and inflammato-ry cell infiltration, respectively. What was more, the percentage of splenic plasma cells ( CD19 -CD138 +) was re-duced significantly, which maybe resulted in the decrease in ANA. However the high level of anti-dsDNA antibody was not influenced by the combination treatment. The serum level of BAFF was also reduced by the combination treatment. Conclusion Prednisone and TACI-Ig combination treatment has a beneficial effect on murine SLE, which may be associated with the inhibition of plasma cell differentiation and the secretion of auto-antibody.

Objective To establish a model in rats for studying the lung injury induced by powder combustion. Methods The explosion box and trauma chamber were constructed based on the fire simulation-platform. The smoke composition was analyzed on-line. The animal clinical manifestation was observed, and the lung water ratio, arterial blood gases, gross appearance and macropathology were analyzed to evaluate the injury level. Results The smoke contents included CO, SO 2, NO and NO 2. When the injury occurred, the CO concentration was 505 23 ppm, and SO 2 concentration was 67?4.8ppm. The time to cause injury was 4 minutes. The tachypnea immediately occurred for most of the rats, then bradypnea and dyspnea. The metabolic acidosis happened at the early stage of injury and the combined effects of metabolic acidosis and respiratory acidosis appeared at the late stage. Water ratio in the lung gradually increased and reached the peak at 6 hours later, and the normality was not recovered after 24 hours. The gross appearance and macropathology proved the lung injury. The obvious bleeding appeared at 4 hours, and the edema reached the most grievous level at 6 hours, and the normality was not recovered after 24 hours. Conclusion The model has been successfully established to study powder combustion-induced acute aspiration lung injury in rats .This model can keep the injury conditions stably and has the benefits of easy-making and repeatable.

ObjectiveTo study the pharmacokinetics of iguratimod in rats. MethodsThe concentration ofiguratirnod in the samples was determined by HPLC method. The pharmacokineties parameters were calculated withDAS softwrare. ResultsThe mainpharmacokineties parameters of normal group(6mg/kg) were as follows:t1/2Ke:3.56h, tpeak: 4.00h, Cmax : 8.87μg/ml, AUC0.24 : 74.76μg· ml-1·h-1. The main pharmacokineties parameters of threemodel groups(3,6,12mg/kg) were as follows: t1/2Ke: 4.54,3.20,3.17h, tpcak:3.83,3.83,4.67h,Cmax:3.84, 8.31,12.69μg/ml, AUC0.24 :40.21,76. 72,117.06μg·ml-1·h-1. Except Cmax and AUC, no significant differenceswere found between the three model groups. And the differences between normal group and model group were notsignificant. ConclusionThe pharmacokinetics of rats ks fit to one-compartment model.

Objective To establish and evaluate a rat model presenting symptoms of arthritis-hypertension disease (AHD).Methods A total of forty healthy 5-6 week-old male SD rats were used in this study.Hypertension was induced by constriction of the left renal artery by two kidney one clip (2K1C) with a 0.25 mm silver clamp, and AHD model was established by injecting 0.1 mL complete Freund adjuvant to the left hind paw.Tail artery pressure was measured with a non-invasive blood pressure measurement system.The degree of swelling in the non-inflammatory joint of rats was measured with a paw volume measuring instrument, the arthritis index and incidence of inflammation were evaluated.The rats were sacrificed on the 35th day.The thoracic aorta, ankle joint and spleen tissues were examined by pathology using HE staining.Results The joint of AHD model rat was significantly swollen, extensive synovial cell hyperplasia, inflammatory cell infiltration, vascular pannus formation, and bone and cartilage destruction.The number of germinal centers in spleen was increased, and a large number of lymphocyte infiltration, diffuse proliferation of white pulp, and red pulp infiltration were present.The arthritis index, incidence of inflammation and histopathological scores of the joint and spleen were significantly higher than adjuvant arthritis (AA) rats;meanwhile, the blood pressure of AHD model rat was significantly increased, the thickness and cross-sectional area of thoracic aorta were significantly increased, while the lumen diameter was significantly reduced.The blood pressure and vascular injury were significantly increased or aggravated compared with the HT rats.Conclusions A rat model of arthritis-hypertension disease is successfully established by using complete Freund adjuvant intradermal injection to the footpad and surgery to narrow the left renal artery.

AIM To investigate the effect of melatonin on collagen-induced arthritis (CIA). METHODS The model of mice CIA was prepared and the change of secondary paw-swelling and the mean scores of arthritis were observed. The level of PGE was assayed by spectrophotometer; Meanwhile, 3H-TdR incorporation was used to detect ConA-and LPS-induced splenocytes proliferation and the production of interleukin (IL)-1 and IL-2. Hepatic pathological examination was performed by Hematoxylin-eosin (HE) stain method. RESULTS Treatment of ig melatonin(10,100, 1 000 ?g?kg -1) significantly decreased inflammation of the arthritis. The increased ConA-induced splenocytes proliferation ,PGE, IL-1 and IL-2 production in mice CIA were reversed by melatonin. Meanwhile, the pathological examination showed that articulus cartilage degeneration with synovial hyperplasia and inflammatory cells infiltration in CIA mice was suppressed by ig melatonin. CONCLUSION Melatonin has inhibitory effect on mice CIA which may be related to its immunoregulative function.

Objective To investigate the role of KAT7 in cartilage cell and tissue ageing by establishing an over-replicating-induced primary mouse cartilage cell ageing model and a mouse natural ageing model.Methods Chon-drocytes of the mouse knee joint were obtained by type Ⅱ collagenase digestion and identified by toluidine blue stai-ning and Col Ⅱ staining.The age-related proteins and KAT7 expression levels in cartilage cells from different gener-ations of mice were discovered using Western blot and cellular immunofluorescence techniques,and the aging of the cells was assessed by SA-β-Gal coloring.The pathological alterations were examined in the joints of 22-month-old mice compared to 2-month-old mice using HE staining and safranin O-solid green staining.Additionally,immuno-histochemical analysis was done to observe the expression of KAT7 and p53 in mouse joint tissue.Results Com-pared with the control group,the expression levels of KAT7 protein and p21 and p53 in aged mouse chondrocytes significantly increased.WM-3835,a commonly inhibitor of KAT7 that possess the capacity on halting the protein expression procedure of gene KAT7 as well as p21 in ageing chondrocytes.SA-β-Gal staining showed a significant increase in positive staining of chondrocytes in the eighth generation(P8)compared to the first generation(P1).Compared with the cartilage tissue of young mice,the cartilage tissue of elderly mice presents a near-bone distribu-tion,with a decrease in cartilage surface integrity,a significant increase in the number of hypertrophic chondro-cytes,and more KAT7 and p53 cells that were positive.Conclusion The expression of KAT7 increases in the ageing chondrocytes and the cartilage tissue of ageing mice,reveales the potential significance of KAT7 correlated to cellular aging process in cartilage.

Objective : To examine the impact and partial mechanism of bupivacaine sustained-release drug ( code PB21) in combination with low-dose dexamethasone ( Dex) on the analgesic time of rats with knee osteoarthritis (KOA) ． Methods : Using the techniques of anterior cruciate ligament transection and meniscus instability，a rat KOA model was created．After eight weeks，SD mice were split into three groups at random : a group for the model， one for Dex (50 μg) ，one for PB21 ( 1. 5 mg) ，and one for combined administration ( 1. 5 mg PB21 /50 μg Dex) ， with a control group that received a sham operation．The pain thresholds of KOA rats were measured using a Pres- sure Application Measurement (PAM) at different intervals before to delivery and 4，24，36，and 48 hours following administration ; to gauge changes in discomfort，a CatWalk was used to assess the rats' average foot strength and maximum contact area before，four，twenty-four，and forty-eight hours after treatment．A portion of the rats were put to sleep at four，twenty-four，and forty-eight hours following the injection，and the joint synovium was removed for paraffin sectioning．Immunohistochemistry was used to identify the expression of GAP43 in the synovium，whereas immunofluorescence was used to identify the expression of CGRP in the same tissue. Results : The average strength and maximum contact area of the foot and claw decreased (P ＜0. 01 ) ，and the pain threshold decreased (P < 0. 01) in the model group compared to the sham operation group．The PB21 + Dex group experienced a delayed pain threshold lowering time delay when compared to the PB21 and Dex treatment groups alone．Up to 48 hours lat- er，the combination administration group's average strength and maximum contact area of the foot paw remained ele- vated，and there was a statistically significant difference (P ＜0. 05 ) between the combined administration group and PB21 and Dex alone．GAP43 and CGRP expression levels in synovial tissue were detected．The results indica- ted that PB21 and Dex alone could lower protein expression levels at 4 and 24 h at the two time points，and that the PB21 + Dex group could still significantly lower GAP43 and CGRP expression levels at 48 h．At the 48 h time point，the PB21 + Dex group was statistically significant when compared to the PB21 and Dex alone administration group(P＜0. 05) ． Conclusion In summary low dose dexamethasone can prolong the analgesic effect of PB21 on KOA rats，which is connected to reducing the expression of pain related proteins CGRP and GAP43 .

Objective: To investigate the therapeutic and immunomodulatory effects of human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) on adjuvant arthritis(AA) rats. Methods: Twenty-four male Sprague-Dawley(SD) rats were established with AA by complete Freund's adjuvant method.They were randomly divided into model group and hUC-MSCs group (2×10⁶ cells/mL, 5×10⁶ cells/mL, tail vein injection), and the Yisaipu group (2.8mg/kg, subcutaneous injection), 6 rats in each group.Another 6 male SD rats were used as the control group.After the model was established, the body weight and paw volume were recorded weekly, the whole body score and the arthritis index score were calculated, and the joint swelling number was calculated.The animals were sacrificed after d35, the weight of thymus and spleen were weighed, and the corresponding index was calculated, the histopathological changes of the ankle joint were observed by HE staining.The percentages of CD4⁺ CD44⁺ T cell and CD4⁺ CD62L⁺ T cell were detected by flow cytometry.The levels of TNF-α, IL-1β in the serum of AA rats were detected by ELISA. Results: hUC-MSCs relieved paw volume, the whole body score and arthritis index score, and the joint swelling number in AA rats (F=20.573, 89.092, 14.161, 10.914, all P<0.01). hUC-MSCs reduced thymus index[(0.120±0.032), (0.120±0.031)] and spleen index[(0.250±0.070), (0.240±0.018)] (F=6.339, 4.105, all P<0.01), improved structural damage of ankle joint.hUC-MSCs could regulate the percentage of T cell subsets(CD4⁺ CD62L⁺ )[(7.0±1.4)%, (7.9±2.2)%], (CD4⁺ CD44⁺ )[(15.0±3.6)%, (12.0±1.9)%] in spleen (F=6.331, 12.719, all P<0.01), and down-regulate the levels of TNF-α [(172.0±13.0)ng/L, (150.0±12.0)ng/L] and IL-1β [(75.0±36.0)ng/L, (74.0±20.0)ng/L] in serum (F=8.221, 3.581, all P<0.05) of AA rats by tail vein injection. Conclusion hUC-MSCs can promote the treatment of AA rats by regulating the function of T cells.

Objective : To study the protective effect and mechanism of iPSC⁃MSCs on cartilage matrix in knee oste⁃ oarthritis (KOA) patients in vitro. Methods : Cartilage tissues removed from KOA patients with joint replacement surgery were collected and subjected to tissue and cellular experiments , respectively. Cartilage tissue was cut into small pieces and randomly divided into a control group , an IL⁃1β ( 10 ng/ml) induction group , and iPSC⁃MSCs 96 h and then co⁃cultured with different amounts of iPSC⁃MSCs ( 1 × 104 , 1 × 105 , 1 × 106 ) cells for 72 h. For in tissues , the pathological changes of isolated cartilage tissues were examined by HE staining. The levels of ADAMTS⁃4 , ADAMTS⁃5 , and type II collagen expression were analyzed by immunohistochemistry , while the levels of MMP13 , IL⁃6 , and IL⁃10 in culture supernatants were detected by ELISA kits. The 2 to 5 generations of chondrocytes , which were extracted from cartilage tissue of KOA patients , were stimulated with IL⁃1β ( 10 ng/ml) for 48 h and then co⁃cultured with different concentrations of iPSC⁃MSCs ( 1 × 104 , 1 × 105 , 1 × 106 ) cells for 72 h. Immunofluorescence and Western blot detected the expression of RUNX2 , ADAMTS⁃4 , and ADAMTS⁃5 in chondrocytes. Results : Comparison with the control group , in the IL⁃1β⁃induced group , the levels of RUNX2 , ADAMTS⁃4 , and ADAMTS⁃5 increased , the level of type II collagen decreased , the levels of MMP⁃13 and IL⁃6 in the culture supernatant increased ( P < 0. 05) , and the level of IL⁃10 decreased ( P < 0. 05) ; Compared with the IL⁃1β⁃induced decreased the expression of RUNX2 , ADAMTS⁃4 , and ADAMTS⁃5 , promoted type II collagen expression and elevated IL⁃10 levels. Conclusion iPSC⁃MSCs inhibited ADAMTS⁃4 and ADAMTS⁃5 expression in vitro , reduced cartilage extracellular matrix degradation , and played a role in articular cartilage protection.

Objective : To investigate the partial mechanism and effect of transplanting with human umbilical cordderived mesenchymal stem cells (hUC⁃MSCs) to repair articular cartilage defects in a rat model. Methods : Critical⁃sized osteochondral defects were created in the trochlear grooves of rat femurs. The hUC⁃MSCs were transplanted into the defect of experimental knees. Sham group and model group knees were transplanted with saline. The effects of articular cartilage repair were evaluated at 10 weeks after surgery with International Cartilage Repair Society (ICRS) repair score , histological examination and immunohistochemical analysis. The effects of hUC⁃MSCs on the proliferation and migration of chondrocytes were detected by Transwell in vitro. Results : After transplanting with hUC⁃MSCs , the articular surfaces of the defect sites were changed smoother thanthose of the model group , and the cellular morphology and arrangement were also improved in Safranin O staining or Masson staining results. Similar to surrounding normal articular cartilage tissue after treatment for 10 weeks , and the ICRS repair score was signifision of type Ⅱ (Col Ⅱ ) collagen and decrease the level of type Ⅰ collagen( Col Ⅰ ) in the articular defect site. Meanwhile , the increased protein expression of SOX9 and protein transportation to the nucleus were observed after treatment with hUC⁃MSCs for 10 weeks. In vitro , chondrocytes could be proliferated and migrated after co⁃cultured with hUC⁃MSCs. Conclusion Transplanting with hUC⁃MSCs can promote cartilage repair, and its role maybe related to the protection of the cartilage matrix and the promotion of chondrocyte proliferation and migration.