Shen B

Hypoxia differentially regulates human nucleus pulposus and annulus fibrosus cell extracellular matrix production in 3D scaffolds

OBJECTIVE We hypothesize that intervertebral disc (IVD) cells from distinct region respond differently to oxygen environment, and that IVD cells from patients with disc degeneration can benefit from hypoxia condition. Therefore, we aimed to determine the transcriptional response and extracellular matrix (ECM) production of nucleus pulposus (NP) and annulus fibrosus (AF) cells to different oxygen tension. METHOD Human NP and AF from degenerated IVD were seeded in 3D scaffolds and subjected to varying oxygen tension (2% and 20%) for 3 weeks. Changes in ECM were evaluated using quantitative real-time reverse transcriptase polymerase chain reaction, histological and immunohistological analyses. RESULTS Hypoxia significantly enhances NP cells phenotype, which resulted in greater production of sulfated glycosaminoglycan (GAG) and collagen type II within the constructs and the cells expressed higher levels of genes encoding NP ECM. A significantly stronger fluorescent signal for hypoxia-inducible factor (HIF-1α) as also found in the NP cells under the hypoxic than normoxic condition. However, there was little effect of hypoxia on the AF cells. CONCLUSIONS The NP and AF cells respond differently to hypoxia condition on the 3D scaffold, and hypoxia could enhance NP phenotype. When used in concert with appropriate scaffold material, human NP cells from degenerated disc could be regenerated for tissue engineering application.

Study on the effect of T-2 toxin combined with low nutrition diet on rat epiphyseal plate growth and development

The purpose of this study was to observe early lesions of rat epiphyseal plates and metaphysis caused by T-2 toxin and T-2 toxin combined with a low nutrition diet to determine possible pathogenic factors of Kashin-Beck disease (KBD). Ninety Wistar rats were divided into three groups. Group A was fed with a normal diet as control; group B was fed with a normal diet and T-2 toxin; and group C was fed with a low nutrition diet and T-2 toxin. The left knee specimens were collected, fixed in formaldehyde solution, stained by hematoxylin and eosin and Masson. After two weeks, the epiphyseal plate showed necrosis of chondrocytes in groups B and C. After four weeks, more obvious chondrocyte necrosis appeared. The positive rate of Lamellar necrosis in group C was significantly higher than that in groups B and A (P < 0.01). Metaphyseal trabecular bone showed sparse disorder and disruption in group C. T-2 toxin combined with a low nutrition diet could lead to more serious chondrocyte necrosis in the epiphyseal plate and disturb metaphyseal trabecular bone formation.

The effect of Kashin-Beck disease-affected feed and T-2 toxin on the bone development of Wistar rats.

Objective:  To investigate the effect of Kashin‐Beck disease (KBD)‐affected feed and T‐2 toxin on the bone development of Wistar rats.

Is there reduced polyethylene wear and longer survival when using a mobile-bearing design in total knee replacement?

The purpose of this study was to undertake a meta-analysis to determine whether there is lower polyethylene wear and longer survival when using mobile-bearing implants in total knee replacement when compared with fixed-bearing implants. Of 975 papers identified, 34 trials were eligible for data extraction and meta-analysis comprising 4754 patients (6861 knees). We found no statistically significant differences between the two designs in terms of the incidence of radiolucent lines, osteolysis, aseptic loosening or survival. There is thus currently no evidence to suggest that the use of mobile-bearing designs reduce polyethylene wear and prolong survival after total knee replacement.

Intra-articular injection of microRNA-140 (miRNA-140) alleviates osteoarthritis (OA) progression by modulating extracellular matrix (ECM) homeostasis in rats

OBJECTIVE Disruptions of extracellular matrix (ECM) homeostasis are key events in the pathogenesis of osteoarthritis (OA). MicroRNA-140 (miRNA-140) is expressed specifically in cartilage and regulates ECM-degrading enzymes. Our objective in this study was to determine if intra-articular injection of miRNA-140 can attenuate OA progression in rats. DESIGN miRNA-140 levels in human normal and OA cartilage derived chondrocytes and synovial fluid were assessed by polymerase chain reaction (PCR). After primary human chondrocytes were transfected with miRNA-140 mimic or inhibitor, PCR and western blotting were performed to quantify Collagen II, MMP-13, and ADAMTS-5 expression. An OA model was induced surgically in rats, and subsequently treated with one single intra-articular injection of miRNA-140 agomir. At 4, 8, and 12 weeks after surgery, OA progression were evaluated macroscopically, histologically, and immunohistochemically in these rats. RESULTS miRNA-140 levels were significantly reduced in human OA cartilage derived chondrocytes and synovial fluid compared with normal chondrocytes and synovial fluid. Overexpressing miRNA-140 in primary human chondrocytes promoted Collagen II expression and inhibited MMP-13 and ADAMTS-5 expression. miRNA-140 levels in rat cartilage were significantly higher in the miRNA-140 agomir group than in the control group. Moreover, behavioural scores, chondrocyte numbers, cartilage thickness and Collagen II expression levels in cartilage were significantly higher, while pathological scores and MMP-13 and ADAMTS-5 expression levels were significantly lower in the miRNA-140 agomir group than in the control group. CONCLUSION Intra-articular injection of miRNA-140 can alleviate OA progression by modulating ECM homeostasis in rats, and may have potential as a new therapy for OA.

Radiographic findings of Wistar rats fed with T-2 toxin and Kashin-Beck disease-affected diet

Objective:  To characterize the features of radiographic abnormalities of the tibial bone in Wistar rats which have been fed T‐2 toxin and Kashin‐Beck disease (KBD) epidemic district food.

Serum levels of IL-1β, IL-6 and TNF-α in rats fed with Kashin-Beck disease-affected diet

Aim:  To investigator the serum level of interleukin (IL)‐1β, IL‐6 and tumor necrosis factor (TNF)‐α in rats which have been fed with Kashin–Beck disease (KBD) epidemic district food.

The arthropathic and functional impairment features of adult Kashin-Beck disease patients in Aba Tibetan area in China

OBJECT The purpose of the study was to analyze the features of arthropathic changes and functional impairments as well as the correlations between them for adult patients suffered with Kashin-Beck disease (KBD) in Aba Tibetan area of Sichuan Province, China. METHOD Nine hundred and eighty-nine adult KBD patients in Aba KBD prevalence area were investigated. The arthropathic changes including arthritic pain (evaluated by visual analog pain score (VAS)), deformity, limited range of joint motion (ROM), as well as daily living and working function were examined, evaluated and analyzed. RESULTS Ninety-two percent of patients suffered with multiple affected joints in both upper and lower extremities. The most frequently affected joints were knee (86.1%) and hand (77.2%). The most painful joints were knee (VAS 7.1 ± 1.9) and elbow (VAS 6.8 ± 2.1). Joint deformities most frequently represented as enlargement of interphalangeal joints (93.2%). Limitation of ROM occurred most frequently in hand (76.7%) and elbow (38.4%). Multiple linear regression analysis revealed that only joint pain (regression coefficient: -0.504, 95% confidence interval (CI): -0.820-0.188, P ＜ 0.001) and ROM (regression coefficient: 0.017, 95% CI: 0.011-0.024, P ＜ 0.001) were independent risk factors affecting daily living and working function. CONCLUSION Most adult patients suffered with multiple affected joints in both upper and lower limbs. The elbow, hand and knee were the most frequently and severely affected joints. The pain and limited ROM were the independent risk factors of daily living and working function.

Evaluation of a biodegradable graft substitute in rabbit bone defect model

Objective: To evaluate a new biodegradable copolymer calcium sulfate/poly amino acid (CS/PAA) as a graft substitute for the repair of the surgically created cancellous bone defects in rabbits and its biological properties in vivo. Materials and Methods: Cancellous bone defects were created by drilling holes in the unilateral lateral aspect of the femoral condyle of New Zealand white rabbits. Three groups were assigned: Group A rabbits were grafted with 80% CS/PAA and group B rabbits were grafted with 95% CS/PAA as two treatment groups; group C was sham-operation control group. To study the osteogenic capability in vivo, specimens were harvested at 4, 8, 12, and 16 weeks after implantation and were evaluated by gross assessment, X-ray, histological examination, and histomorphometry. In order to identify the molecular mechanism of bone defect repair, the expression of bone morphogenetic protein-2 (BMP-2) and vascular endothelial growth factor (VEGF) was detected using Western blot at 4 weeks. Results: Group A and group B showed more vigorous and rapid repair leading to regeneration of cancellous bone than sham-operation control group on gross observation, radiology, and histomorphometry. There was no significant difference between groups A and B. Morphological observation and histological examination showed that the copolymers degraded in sync with the new bone formation process. The expression of BMP-2 and VEGF in implantation groups was higher than that in control group by western blot. Conclusion: These findings demonstrated that the novel biodegradable copolymers can repair large areas of cancellous bone defects. With its controllable degradation rate, it suggests that CS/PAA may be a series of useful therapeutic substitute for bone defects.

[The efficacy and safety of postoperative retransfusion drain following total hip arthroplasty: a Meta-analysis].

OBJECTIVE To investigate the effectiveness and safety of post-operative retransfusion drain(PRD) after total hip arthroplasty. METHODS A systematic literature review based on PubMed, EMBase, the Cochrane Library, China Biology Medicine disc, CNKI, VIP and WanFang Database in any language regarding PRD following total hip arthroplasty was performed.The data was evaluated using modified Jadad score and then analyzed using RevMan 5.2. RESULTS Nine randomized controlled trials totaling 1 824 patients, 913 patients in PRD group and 911 in control group, were eligible for data extraction and Meta-analysis.The results indicated that the use of PRD could reduce the requirement of allogeneic blood transfusion when compared with ordinary vacuum drainage (RR=0.61, 95% CI= 0.47-0.79), but the benefit was not found when compared with no drainage group(RR=1.07, 95% CI=0.67-1.71). And the postoperative hemoglobin level was higher in PRD group(MD=0.14, 95% CI=0.01-0.27, P=0.04). No significant difference was identified regarding transfusion index, length of hospital stay, the incidence of febrile reaction and wound-related complications. CONCLUSIONS PRD in reducing requirement of blood transfusion following THA is effective and safe when compared with ordinary vacuum drainage, but the benefit is not found when compared with no drainage.And more robust evidence is needed to confirm this result.