The field of tissue engineering is paying more attention to bone marrow mesenchymal stem cells.This review focuses on the recent advancement of induced chondrocytes of mesenchymal stem cells including the following aspects: physical conditions of cell culture,growth factors and their regulative mechanism,and gene enhanced tissue engineering.

Objective To study the protective role of continuous veno-venous hemofiltration (CVVH) in cardiac insufficiency refractory to diuretic therapy after acute myocardial infarction.Methods A total of 104 acute myocardial infarction patients admitted from march 2012 to march 2016 were recruited.According to their wishes,the patients were divided into two groups,continuous veno-venous hemofiltration combined with routine therapy as experimental group (n =52) and conventional treatment as control group (n =52).Mortality rate within one month,the mean length of ICU stay,the mean length of hospital stay,ventilator usage and urine output volume were documented.Then the difference in BW between pre-and post-treatment was determined for evaluation of fluid retention,and blood plasma C-reactive protein (ΔCRP),interleukin 6 (ΔIL-6),interleukin 8 (ΔIL-8),tumor necrosis factor-α (ΔTNF-α) and left ventricular ejection fraction (ΔLVEF) were measured and calculated.A multiple linear regression model to predict ΔLVEF was established.Data recorded at different intervals in the same group were analyzed by ANOVA.Data of the monitoring biomarkers,the mean length of ICU stay,the mean length of hospital stay of two groups were recorded at the same given intervals were analyzed by t test.Data of mortality rate within one month,drugs and ventilator usage in two groups were analyzed by x2 test.P value less than 0.05 was considered statistically significant.Results There were significant differences in mortality rate within one month,the mean length of ICU stay,the mean length of hospital stay,and the duration of ventilator usage between the two groups (P ＜ 0.05).Total volume of fluid output (urine and ultrafiltration volume) was higher in experiment group than that in control group in 48 hours after the treatment (P ＜ 0.01).The levels of CRP,IL-6,IL-8 and TNF-α decreased significantly (P ＜ 0.05) in experiment group after treatment but not in control group (P ＞ 0.05) as compared with those before the treatment.BW was decreased and LVEF was increased in both groups after treatment (P ＜ 0.05) compared with those before the treatment.Levels of CRP,IL-6,IL-8 and TNF-α were lower in experiment group than those in control group after treatment (P ＜ 0.05).BW was meagerly lower and LVEF was meagerly higher in experiment group than those in control group without statistical significance (P ＞ 0.05).However,the degrees of ΔLVEF andΔBW were greater in experiment group than those in control group (P ＜ 0.01).In experiment group,significantly positive correlations were found among ΔBW,ΔCRP,ΔIL-6,ΔIL-8,ΔTNF-α and ΔLVEF (P ＜0.05).Multiple linear regression analyses showed that ΔBW and ΔTNF-α were the independent factors forΔLVEF and ΔBW was the main independent factor for ΔLVEF in control group.ΔLVEF was positively correlated with ΔBW (P＜0.01) but had no correlation with ΔCRP,ΔIL-6,ΔIL-8 and ΔTNF-α (P ＞0.05).Multiple 1inear regression analyses showed that only ΔBW was the independent factor for ΔLVEF.Conclusion CVVH plays protective role in acute myocardial infarction patients with consequent cardiac insufficiency refractory to diuretic therapy by clearance of inflammatory cytokines and removal of retained fluid,and the removal of retained fluid is the most import mechanism to protect heart function.

ObjectiveTo study the histologic changes of contracture Achilles tendon under Ilizarov distraction technique.MethodsEighteen dogs were installed ilizarov external fixation frames on the right hind leg in a neutral position.Pull traction started 1 week postoperatively with speed of 1 mm/day for 3 weeks.After 15 degrees of foot drop,the fixation was still maintained for 3 weeks.Nine animals were randomly selected and put to death(Contracture group),other animals corrected for 3 weeks with the same speed and methods,then put to death(Force group),health specimens as control group.(1)Observe tendon cells arranged distribution and collagen fiber form with HE dyeing,and analysis of tendon retinal thickness with image analysis software.(2)Observe collagen Ⅰ and Ⅲ with picrosirius red dying,and analyzed both content changes with image analysis software.(3)Determination of protein contents of polysaccharide with phloroglucinol spectrophotometry.Results (1)In the contracture group,the collagenous fibre gap was not obvious,the tendon cell assumes spindle-shaped,saccate,the collagen fibrous bundle distortion,the arrangement was scattered in disorder,difficult to see the intercellular substance.Tendon retinal thickness showed obvious differences with the health side (Control group).In the force group,the tendon cells were round or oval,located in collagen bundles in a string of alignment,inflammatory cells were seen.Tendon retinal thickness showed no differences with the health side.(2)With polarized light microscopy,the collagen Ⅰ and collagen Ⅲ composition proportion in the contracture group showed obvious differences with the control group,force group had not obvious differences with health side.(3)The content of polysaccharide in the contracture group were obviously reduced,while force group returned to normal level.ConclusionThe tissue form of contracture Achilles tendon can recovered to normal with the Ilizarov technology.

OBJECTIVE:To improve the quality of ADR reports. METHODS:By using intensive hospital monitoring mode, ADR reports before and after the application of the system would be collected and factors as report quantity,type,time and quality of reports were analyzed statistically. RESULTS:It provided rapid reporting function after the implementotion of the system. Total quantity of reported ADR cases increased from 589 to 748,and the proportion of all the serious ADR reports increased from 62.8%to 11.76%. The score of repert quality increased from 93.64 to 98.36,the proportion of time-out reports increased from 94.05% to 97.33%,with statistical significance (P<0.05). CONCLUSIONS:Rapid reporting system of ADR in the hospital is beneficial to improve the efficiency and guarantee the quality of the reports. It also can expand the coverage of the monitoring network,and can lay the foundation for drug safety scientific evaluation and monitoring.

ObjectiveTo investigate the efficiency of autologous transplantation of peripheral blood stem cells for treatment of patients with diabetic lower limb ischemia.MethodsEighteen patients of type 2 diabetes with diabetic lower limb ischemia (30 legs) were treated by autologous transplantation of peripheral blood stem cells.ResultsThe limb pain, cool feeling and numbness feeling improved significantly after PBSC transplantation,the improvement rate were 96.7％, 100.0％ and 95.8％ respectively.Intermittent claudication was also relieved significantly, total remission rate was 76.9％.The ABI and TcPO2 of patients increased significantly at 3 months after transplantation.After the transplantation ABI raised from 0.60 ± 0.11 to 0.71 ±0.12(t =-6.882, P ＜ 0.01) .93.3％ of patients' TcPO2 raised in different degrees.The foot infections were well controlled.Ulcer or toes gangrene got better or healed.No obvious complications or adverse reaction were observed after the transplantation.ConclusionAutologous transplantation of peripheral blood stem cells shows to be a simple, safe and effective method in treating patients with diabetic lower limb ischemia.

Objective To investigate the influences on the femur cortex of the rabbit after ovariectomy and its mechanism.Methods Eighty 6 months-old female pure New Zealand rabbits were divided into two groups:40 rabbits in ovariectomy group and 40 in sham-operation group.The weight averaged 2.2±0.28 kg.Four weeks and 8 weeks after operation,a series of tests were performed in both groups concerning the number,the volume,the rate and the maximal load of cortical bone porosity.The number,the length and the density of linear crack in rabbit femur cortex were documented after repetitive application of minor trauma.Results Micro-CT demonstrated that both on week 4 and 8 after operation,the number,the volume and the rate of cortical bone porosity were all significantly higher in ovariectomy group than that of the control group.Four weeks after operation,the biomechanical test showed the significantly lower average maximal load of rabbit femur in ovariectomy group (1 892.60±59.09) than that of in control group (1 949.25±53.12) (P=0.003).Eight weeks after operation,the average load of both groups decreased to some extent,which was 1 944.55±41.76 in control group and 1 692.40±85.08 in ovariectomy group respectively (P=0.000).However,the average maximal load of ovariectomy group decreased more significantly.Having application of repetitive minor trauma to the bone,the number,the length and the density of linear crack of cortical bone were 3.40± 1.67,216.80± 17.60 μm and 0.40±0.08/mm2 in ovariectomy group,and 2.00± 1.17,160.45± 16.89 μm and 0.29±0.13/mm2 in control group 4 weeks later.And after 8 weeks,they were 5.15±1.18,334.60±13.94 μm and 0.35±0.10/mm2 in ovariectomy group,and 3.10±1.37,182.10±9.80 μm and 0.24±0.09/mm2 in control group.The number,the length and the density of linear crack of cortical bone were all significantly higher in ovariectomy group than that of in control group both on week 4 and on week 8 after operation.Conclusion Ovariectomy increases the porosity of cortical bone of rabbit,destroys its biological property,accelerates the fatigued damage and delays the healing process.These changes may be attributed to fracture and delayed union after fracture.

Objective To explore the curative effect of knee flexion deformity on spastic cerebral palsy treatment method.Methods All of 30 patients with spastic cerebral and knee flexion deformity were randomly divided into two groups:traditional operation group and modified operation group,using the commonly used operation (In 15 cases,with traditional hamstring post surgery) and) modified operation (In 15 cases,with modified hamstring post surgery),two groups of patients were treated with Ilizarov external fixation drafting device in the correction of knee flexion deformity after soft tissue release.Adjustment began 7 days after the soft tissue release operation of external fixation,and stretched approximately 0.2 degrees each time,3 times/d,until knee flexion deformity was corrected to hyperextension for 10 degree and maintained for 3 weeks,and the flexion contracture degree of knee joint was measured every 2 weeks;then the Ilizarov external fixation drafting device was removed.Then wear a walking straight leg brace for more than 3 months,until the knee walking function is good.Clinical evaluation included the joint pain index,walking function index,knee flexion deformity degree and range of joint motion score of Dimeglio standard.Results Flexion contracture deformity of knee joint in 30 cases (60 knees) was corrected when Ilizarov external fixator was removed,knee extension to 0 degrees-5 degrees.The two groups of patients had the knee flexion angle range of-1.2 degrees to 13.3 degrees,with an average of (7.32°±3.41°) after removed of the walking straight leg brace,in which 4 cases (8 joints) got recurrent deformity of 10°-15° at the time of removing of the walking straight leg brace.Knee activity significantly was improved at the end of treatment.60 cases of knee joint activity were close to normal,with flexion of 100 degrees to 135 degrees,extension of 0 degrees to 10 degrees.Two groups of patients were statistically significantly improved before and after surgery.Curative effect comparison:The walking function index of the modified operation group was obviously superior to that of the traditional operation group,there was significant statistical difference.There were no statistically significant differences in pain index,knee flexion,and range of joint motion.Conclusion For the treatment of flexion deformity of the knee joint in spastic cerebral palsy,traditional surgery using the semitendinosus and gracilis,post and semimembranosus lysis,combined with the Ilizarov draft external fixation could improve the walking function of the patients,simplify the surgical incision and reduce trauma.As a result,modified hamstring post surgery is an ideal,effective treatment method.

Objective:To recognize the characteristics of necrotizing fasciitis patients complicated with sepsis and summarize the experience the treatment.Methods:A retrospective study was conducted. The clinical data of 57 patients with necrotizing fasciitis complicated with sepsis admitted to Guangdong Provincial People's Hospital from July 2009 to December 2019 was analyzed by collecting such factors as gender, age, complications, infection sites, pathogens, surgery information, treatment options and outcome. The patients were divided into debridement group ( n = 14) and control group ( n = 43) according to whether the debridement was completed within 48 hours of admission, and the mortality during hospitalization between the two groups was compared. A telephone follow-up had been done to record the long-term outcome of these patients. Results:Among 57 patients with necrotizing fasciitis complicated with sepsis, there were 43 males and 14 females with the average age of (57.9±12.1) years old. Most of the underlying diseases were diabetes mellitus (70.17%), other diseases included hypertension (8.77%), tumor chemotherapy (7.02%), liver disease (hepatitis, cirrhosis, 7.02%), coronary artery heart disease (3.51%), systemic lupus erythematosus (3.51%), etc. Most of the infection site was lower limbs (71.93%). There were 78 pathogens cultured in 57 patients, in which 52 were non-drug resistant bacteria (66.67%), and 26 were drug resistant bacteria (33.33%). There were 40 Gram positive (G +) bacteria (51.28%), 29 Gram negative (G -) bacteria (37.18%), 8 fungi (10.26%) and 1 mixed bacteria (1.28%). Finally, of 57 patients, 46 patients were cured, and 11 patients died with hospital mortality of 19.30%. Among 57 patients, the hospital mortality in the debridement group was significantly lower than that in the control group [0% (0/14) vs. 25.58% (11/43), P < 0.05]. Among the 46 cured patients, 11 had accepted amputations, accounting for 23.91%. In December 2020, 43 patients who were cured (3 patients were lost to follow-up) were followed up by telephone. Twenty-three patients were completely self-care, 9 patients were partly self-care, 8 patients were completely unable to take care of themselves, and 3 patients died. Conclusions:Necrotizing fasciitis with sepsis mostly occurs in people with weakened immunity, and has a high mortality and disability rate. Early identification and active surgical debridement may be the key to improve the treatment effect.

Objective To investigate the potential protective effects of valproic acid (VPA) on gut barrier function after major burn injury in rats and its mechanism.Methods Forty male Sprague-Dawley (SD) rats were divided into sham + normal saline (NS),sham + VPA,scald + NS,and scald + VPA groups,with 10 rats in each group.Rat with 55％ total body surface area (TBSA) third-degree severe-bums model was reproduced by immersing into 80 ℃ water,and the rats in sham groups were given sham-bums by immersing into 37 ℃ water.The rats after severebums were immediately treated with 0.25 mL of 300 mg/kg VPA or NS by subcutaneous injection.Rats were sacrificed at 2 hours and 6 hours after injury,and abdominal aortic blood and ileal tissue were harvested.The levels of vascular endothelial growth factor (VEGF) were determined by enzyme-linked immunosorbent assay (ELISA).The intestinal permeability was evaluated by fluorescein isothiocyanate-dextran (FITC-dextran) determination.The histomorphological changes in gut barrier were evaluated by Chiu grading system.Levels of acetylated lysine at the ninth position of histone 3 protein (Ac-H3K9),hypoxia-inducible factor 1α (HIF-1α),zona occludens 1 (ZO-1) and myosin light chain kinase (MLCK) were determined by immunofluorescence staining and Western Blot.Results Compared with sham + NS group,rats in scald + NS group showed intestinal mucosal damage 2 hours after bum injury,as well as increased mucosal permeability,protein expression levels of HIF-1 α,VEGF,MLCK,and lowered levels of AC-H3K9 and ZO-1.These changes were much more prominent at 6 hours after injury.VPA treatment significantly attenuated the bum-induced intestinal damage.Compared with scald + NS group,the protective effects in scald + VPA group was not evident at 2 hours after injury;however,intestinal damage was much less severe at 6 hours after injury (Chiu score:2.03 ± 0.27 vs.3.12 ± 0.15),intestinal permeability was significantly decreased [FITC-dextran (μg/L):709 ± 76 vs.1138 ± 75],histone acetylation was enhanced [Ac-H3K9 (gray value):1.55 ± 0.12 vs.0.48±0.12],ZO-1 degradation was significantly inhibited (gray value:0.69 ± 0.12 vs.0.43 ± 0.16),the protein expression levels of VEGF and MLCK were significantly down-regulated [VEGF (ng/mg):51.7±3.7 vs.71.2±4.3,MLCK (gray value):1.98±0.20 vs.2.80±0.24],while the HIF-1 α protein expression levels were significantly reduced at both 2 hours and 6 hours after injury (gray value:2.50±0.39 vs.3.88±0.42 at 2 hours,1.83±0.42 vs.4.42±0.41 at 6 hours,all P ＜ 0.05).Conclusions Severe bum injury can induce histone deacetylation,ZO-1 degradation and intestinal barrier dysfunction.VPA can improve the levels of histone acetylation and ZO-1,and protect intestinal epithelial barrier function.These may probably be mediated through inhibiting HIF-1α and its downstream gene VEGF and MLCK.

Objective: To explore the effects of allogeneic bone marrow mesenchymal stem cells (BMSCs) on polarization of peritoneal macrophages isolated from rats with sepsis induced by endotoxin/lipopolysaccharide (LPS). Methods: (1) BMSCs were isolated, cultured and purified from 5 SD rats with whole bone marrow adherent method. The third passage of cells were collected for morphologic observation, detection of expressions of stem cell surface markers CD29, CD44, CD45, and CD90 with flow cytometer, and identification of osteogenic and adipogenic differentiation. (2) Another 45 SD rats were divided into sham injury group (SI, n=5), LPS control group (LC, n=20), and BMSCs-treated group (BT, n=20) according to the random number table. Rats in groups LC and BT were injected with LPS (5 mg/kg) via tail vein to induce sepsis; rats in group SI were injected with the same amount of normal saline to simulate the damage. At post injury hour (PIH) 1, rats in group BT were given 1 mL BMSCs (2×10⁶/mL) via tail vein injection; rats in another two groups were injected with equal volume of phosphate buffer saline. Five rats in group SI at PIH 24 and in groups LC and BT at PIH 6, 12, 24, and 48 were sacrificed to harvest lung tissue for pathological observation with HE staining. In addition, rats in group SI at PIH 24 and in groups LC and BT at PIH 24 and 48 were simultaneously performed with intraperitoneal injection of low-glucose DMEM. Then peritoneal fluid was harvested to culture peritoneal macrophages. Flow cytometer was used to assess the positive expression of cell makers of macrophages including CD68 (making gate), CD11c, and CD206 in group SI at PIH 24 and in groups LC and BT at PIH 24 and 48. Data were processed with one-way analysis of variance and LSD test. Results: (1) The third passage of cells showed uniform fiber-like shape similar to fibroblasts. These cells showed positive expressions of CD29, CD44, CD90 and weak positive expression of CD45. They were able to differentiate into osteoblasts and adipocytes. These cells were identified as BMSCs. (2) At PIH 24, the structure of pulmonary alveoli of rats in group SI was clear and complete with no congestion or inflammatory cell infiltration. At PIH 6, the structure of pulmonary alveoli of rats in groups LC and BT was clear with a small amount of inflammatory cell infiltration, slight congestion and pulmonary interstitial thickening. At PIH 12, the inflammatory responses in lung tissue of rats in group LC were more severe than those in group BT with a large amount of inflammatory cell infiltration, serious congestion, and obvious pulmonary interstitial thickening. The pathological results of rats in group BT at PIH 12 was consistent with the results at PIH 6. At PIH 24, the pathological results of rats in groups LC and BT were similar to the results at PIH 12. At PIH 48, the structure of pulmonary alveoli tissue of rats in group LC was still severely disrupted, with a large number of inflammatory cell infiltration and congestion in lung tissue, but pulmonary interstitial thickening was slightly alleviated than before. The condition of rats in group BT nearly recovered to that in group SI. (3) At PIH 24, the positive expression rate of CD11c in peritoneal macrophages of rats in group LC [(83±10)%] was close to that in group BT [(87±7)%, P>0.05], and they were both significantly higher than the rate in group SI [(55±12)%, with P values below 0.01]. The positive expression rate of CD11c in peritoneal macrophages of rats in group LC [(59±11)%] at PIH 48 was close to that in group SI at PIH 24 (P>0.05), and they were both significantly higher than the rate in group BT [(20±11)%] at PIH 48 (with P values below 0.01). At PIH 24, the positive expression percentages of CD206 in peritoneal macrophages of rats were similar among the three groups (with P values above 0.05). The positive expression percentage of CD206 in peritoneal macrophages of rats in group SI at PIH 24 was close to that in group BT at PIH 48 (P>0.05), and they were both significantly lower than the percentage in group LC at PIH 48 (with P values below 0.01). Conclusions BMSCs can reduce the pathological inflammatory responses in the lung of rats with sepsis and inhibit peritoneal macrophages from polarizing into M1 phenotype, whereas they can not promote macrophages to polarize into M2 phenotype.