OBJECTIVE: To evaluate the effect of biodegradable magnesium alloy materials in promoting tendon-bone healing during rotator cuff tear repair and to investigate their potential underlying biological mechanisms. METHODS: Forty-eight 8-week-old Sprague Dawley rats were taken and randomly divided into groups A, B, and C. Rotator cuff tear models were created and repaired using magnesium alloy sutures in group A and Vicryl Plus 4-0 absorbable sutures in group B, while only subcutaneous incisions and sutures were performed in group C. Organ samples of groups A and B were taken for HE staining at 1 and 2 weeks after operation to evaluate the safety of magnesium alloy, and specimens from the supraspinatus tendon and proximal humerus were harvested at 2, 4, 8, and 12 weeks after operation. The specimens were observed macroscopically at 4 and 12 weeks after operation. Biomechanical tests were performed at 4, 8, and 12 weeks to test the ultimate load and stiffness of the healing sites in groups A and B. At 2, 4, and 12 weeks, the specimens were subjected to the following tests: Micro-CT to evaluate the formation of bone tunnels in groups A and B, HE staining and Masson staining to observe the regeneration of fibrocartilage at the tendon-bone interface after decalcification and sectioning, and Goldner trichrome staining to evaluate the calcification. Immunohistochemical staining was performed to detect the expressions of angiogenic factors, including vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP-2), as well as osteogenic factors at the tendon-bone interface. Additionally, immunofluorescence staining was used to examine the expressions of Arginase 1 and Integrin beta-2 to assess M1 and M2 macrophage polarization at the tendon-bone interface. The role of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway in tendon-bone healing was further analyzed using real-time fluorescence quantitative PCR. RESULTS: Analysis of visceral sections revealed that magnesium ions released during the degradation of magnesium alloys did not cause significant toxic effects on organs such as the heart, liver, spleen, lungs, and kidneys, indicating good biosafety. Histological analysis further demonstrated that fibrocartilage regeneration at the tendon-bone interface in group A occurred earlier, and the amount of fibrocartilage was significantly greater compared to group B, suggesting a positive effect of magnesium alloy material on tendon-bone interface repair. Additionally, Micro-CT analysis results revealed that bone tunnel formation occurred more rapidly in group A compared to group B, further supporting the beneficial effect of magnesium alloy on bone healing. Biomechanical testing showed that the ultimate load in group A was consistently higher than in group B, and the stiffness of group A was also greater than that of group B at 4 weeks, indicating stronger tissue-carrying capacity following tendon-bone interface repair and highlighting the potential of magnesium alloy in enhancing tendon-bone healing. Immunohistochemical staining results indicated that the expressions of VEGF and BMP-2 were significantly upregulated during the early stages of healing, suggesting that magnesium alloy effectively promoted angiogenesis and bone formation, thereby accelerating the tendon-bone healing process. Immunofluorescence staining further revealed that magnesium ions exerted significant anti-inflammatory effects by regulating macrophage polarization, promoting their shift toward the M2 phenotype. Real-time fluorescence quantitative PCR results demonstrated that magnesium ions could facilitate tendon-bone healing by modulating the PI3K/AKT signaling pathway. CONCLUSION Biodegradable magnesium alloy material accelerated fibrocartilage regeneration and calcification at the tendon-bone interface in rat rotator cuff tear repair by regulating the PI3K/AKT signaling pathway, thereby significantly enhancing tendon-bone healing.
Animals ; Rotator Cuff Injuries/metabolism* ; Rats, Sprague-Dawley ; Signal Transduction ; Wound Healing/drug effects* ; Alloys/pharmacology* ; Rats ; Proto-Oncogene Proteins c-akt/metabolism* ; Rotator Cuff/metabolism* ; Macrophages/metabolism* ; Magnesium/pharmacology* ; Phosphatidylinositol 3-Kinases/metabolism* ; Vascular Endothelial Growth Factor A/metabolism* ; Male ; Biocompatible Materials ; Bone Morphogenetic Protein 2/metabolism*

Objective: To evaluate the antiseptic effect of combined using of 5% sodium hypochlorite and calcium silicate-based root canal sealer against Enterococcus faecalis (Ef) biofilms in infected dentinal tubules in vitro. Methods: Cells of Ef were inoculated into the dentinal tubules of single-rooted teeth (without caries, periapical lesions and malformations extracted due to periodontal disease or orthodontic reasons; collected from Department of Maxillofacial Surgery, The First Affiliated Hospital of Zhengzhou University) with centrifugation and incubated in brain-heart infusion (BHI) to form 3-week-old biofilms. The infected samples were subjected to sodium hypochlorite or sterile water bathing for 10 minutes followed by calcium silicate-based root canal sealer (iRoot SP) (calcium silicate-based group), Gutta-percha group and sterile water group placed on the root canal wall for 1, 4 and 12 weeks. There were two samples in each treatment at each point. The antiseptic effectiveness of combined use of sodium hypochlorite and calcium silicate-based root canal sealer was analyzed by laser scanning confocal microscope (LSCM), ANOVA and LSD-t test. Results: After treatment with 5% sodium hypochlorite, in calcium silicate-based group for 4 and 12 weeks more Ef biofilm cells [(75.3±3.5)% and (74.8±3.8)%] were killed than in Gutta-percha group [(65.9±4.1)% and (63.0±3.7)%] and sterile water group [(63.9±4.0)% and (64.2±3.5)%] (P<0.05). After being treated with sterile water, the proportion of dead bacterial cells in calcium silicate-based group for 1, 4 and 12 weeks [(27.5±4.6)%, (43.0±4.4)% and (40.3±6.1)%] were more than those in Gutta-percha group and sterile water group (P<0.05). After being treated with 5% sodium hypochlorite or sterile water, more biofilm bacteria were killed in calcium silicate-based group for 4 and 12 weeks than in calcium silicate-based group for 1 week (P<0.05). Conclusions The combined use of sodium hypochlorite and calcium silicate-based root canal sealer kills more biofilm cells in infected dentinal tubules.

To evaluate the antiseptic effect of combined using of 5% sodium hypochlorite and calcium silicate?based root canal sealer against Enterococcus faecalis (Ef) biofilms in infected dentinal tubules in vitro . Methods Cells of Ef were inoculated into the dentinal tubules of single?rooted teeth (without caries, periapical lesions and malformations extracted due to periodontal disease or orthodontic reasons; collected from Department of Maxillofacial Surgery, The First Affiliated Hospital of Zhengzhou University) with centrifugation and incubated in brain?heart infusion (BHI) to form 3?week?old biofilms. The infected samples were subjected to sodium hypochlorite or sterile water bathing for 10 minutes followed by calcium silicate?based root canal sealer (iRoot SP) (calcium silicate?based group), Gutta?percha group and sterile water group placed on the root canal wall for 1, 4 and 12 weeks. There were two samples in each treatment at each point. The antiseptic effectiveness of combined use of sodium hypochlorite and calcium silicate?based root canal sealer was analyzed by laser scanning confocal microscope (LSCM), ANOVA and LSD?t test. Results After treatment with 5% sodium hypochlorite,in calcium silicate?based group for 4 and 12 weeks more Ef biofilm cells [(75.3 ± 3.5)% and (74.8 ± 3.8)% ] were killed than in Gutta?percha group [(65.9±4.1)% and (63.0±3.7)%] and sterile water group [(63.9±4.0)% and (64.2±3.5)%] (P<0.05). After being treated with sterile water, the proportion of dead bacterial cells in calcium silicate?based group for 1, 4 and 12 weeks [(27.5±4.6)%, (43.0±4.4)% and (40.3±6.1)%] were more than those in Gutta?percha group and sterile water group (P<0.05). After being treated with 5% sodium hypochlorite or sterile water, more biofilm bacteria were killed in calcium silicate?based group for 4 and 12 weeks than in calcium silicate?based group for 1 week (P<0.05). Conclusions The combined use of sodium hypochlorite and calcium silicate?based root canal sealer kills more biofilm cells in infected dentinal tubules.

Objective: To evaluate the antimicrobial activity of nonequilibrium plasma against Enterococcus faecalis (Ef) biofilms in vitro and to obtain novel evidence of root canal disinfection with nonequilibrium plasma. Methods: Sterile cover slips and single-rooted canals were filled with Ef and incubated to form 1-week-old and 3-week-old biofilms, respectively. The infected samples were subjected to nonequilibrium plasma, 2% chlorhexidine digluconate (CHX) and saline for 3, 10 and 30 minutes, respectively. After treatment, the killing effectiveness of nonequilibrium plasma was analyzed by using laser scanning confocal microscopy (LSCM) and colony forming unit (CFU) counting. Results: The 3-dimentional reconstruction LSCM images showed that about 48.3%-79.8% of 1-week-old Ef biofilm cells and 40.0%-67.4% of 3-week-old biofilm cells were killed by nonequilibrium plasma and 2% CHX compared to saline (P<0.05). The proportion of killing activity was lower after 3 minutes (40.0%-50.9% killing) than after 10 minutes (65.3%-77.8% killing) and 30 minutes (66.4%-79.8% killing) (P<0.05). And the killing of biofilm bacteria was fastest during the first 3 minutes (13.3%-17.0% killing per minute) and slow down greatly after 10 minutes. Remarkably more bacteria were killed in 1-week-old Ef biofilms (48.3%-79.8% killing) than in 3-week-old biofilms (P<0.05). Conclusions The nonequilibrium plasma killed more Ef biofilm cells in infected root canals showed promotional as an additional approach against bacterial biofilms during root canal disinfection.

Objective To investigate the safety and efficacy of mechanical thrombectomy (MT) compared with In?tra-arterial Thrombolysis (IAT) treatment in patients with severe acute ischemic stroke (AIS) caused by large cerebral ar?tery occlusion. Method The patients with AIS caused by large cerebral artery occlusion and underwent MT or IAT from 2005 May to 2014 May was included. A retrospective analysis was conducted on the onset to emergency(OTE)time, emergency to acupuncture(ETA)time, acupuncture to recanalization (ATR) time, stroke severity as measured by the Na?tional Institutes of Health Stroke Scale (NIHSS) score, and site of arterial occlusion on magnetic resonance angiography (MRA). A comparison was made between MT and IAT patients in rates of recanalization, symptomatic intracranial bleed?ing (SIB), mortality, and functional outcome. Three-month favourable outcome was defined as a modified Rankin Scale (mRS) score≤2. Result One hundred and two AIS patients were treated with MT and 50 with IAT. There was no differ?ence between MT and IAT groups with regard to demographics, onset NIHSS score (13.37±6.95 vs. 12.70±6.11;P=0.572) and discharge NIHSS score (8.40 ± 6.69 vs. 7.53 ± 7.28, P= 0.522) and the change of NIHSS score (3.87 ± 7.14 vs. 4.26 ± 5.42, P=0.766). There were significantly differences between MT and IAT groups in the OTE time (Median 300 min vs. 120 min,Z=-5.704,P=0.000) , ATR time (Median 30 min vs. 65 min,Z=-5.011,P=0.001) ,recanalization (91.2%vs. 60.0%,P =0.01),the rate of AIB(21.7% vs. 36.0%,P =0.046),3-month mortality (16.6% vs. 26.0%,P =0.043). The above parameters were better in MT group than in the IAT group. There were no significant differences between MT and IAT groups in the rate of SIB (12% vs. 16%,P =0.055), the NIHSS change(Median 3 vs. 4,Z =-0.236,P =0.823) and mRS score on 90d ( 48.2%vs. 46.0%, P=0.823). MT patients had significantly higher percentages of stent use (22.5%vs. 8%,P=0.018) . The Recanalization for ICA(81.8%vs. 55.6%,P=0.048),BA(93.1%vs. 55.6%,P=0.032)and MCA( 97.5% vs. 60.0%,P =0.026)was higher in MT group than in IAT group .The SIB rate for ICA(13.8% vs. 33.3%,P =0.000),BA(13.8%vs. 33.3%,P=0.000)was lower in MT group than in IAT group . The mortality rate of was significant?ly lower in MT than in IAT group for MCA (2.5%vs. 20.0%,P=0.000) . the good outcome rate for BA was higher in MT group than in IAT group(41.3%vs. 22.2%,P﹤0.01). Conclusions Compared to IAT,MT can provide broader time win?dow,higher recanalization rate and better outcome in patients with severe acute ischemic stroke (AIS) caused by large ce?rebral artery occlusion.

Objective To evaluate traditional surgical treatment, intraluminal strategy and hybrid operation on revascularization of atherosclerosis obliterans (ASO) of the lower extremity. Methods Clinical data of 197 ASO cases receiving revascularization from January, 1998 to December, 2008 were retrospectively analyzed. Seventy-seven cases underwent surgical treatment, 82 cases received intraluminal therapy, and 38 cases were treated by hybrid operation. The indications, clinical effect, complication and perioperational mortality of these three strategies were evaluated. Results 71% patients (164 cases) were followed up from 2 to 112 months. Surgical and intraluminal method had no statistical difference on long-term patency of aortic-iliac and femoral-popliteal artery (57% vs. 51%;48% vs. 42%). Hybrid procedure led to higher patency on multi-level lesion and concurrent thrombosis. The complications after surgery was higher than intraluminal on aortic- iliac and femoral-popliteal artery (31% vs. 12%;31% vs. 11%), and higher than intraluminal and hybrid on multi-level lesion (36% vs. 12% vs. 15%). The perioperative mortality of surgical group was 1.5% and 2.0% on aortic-iliac and multilevel lesion and 0% on other site;and that of intraluminal and hybrid procedure was 0%. Conclusion For aortic-iliac and femoral-popliteal artery revascularization, surgery was preferred in cases of long occlusive lesion and intervention was preferred for cases with short non-occlusive lesion. Hybrid procedure was the best for multi-level and concurrent thrombosis.

Objective To investigate the clinical manifestations, angiographic features and clinical significance of kinking of extracranial internal carotid artery (ICA). Methods The clinical and radiological data of 21 patients with kinking of extracranial ICA were retrospectively reviewed in our hospital from April 2003 to July 2007. Fisher exact test was performed. Results Of the 21 patients, 7 hod no clinical symptoms, the other 14 showed manifestations of cerebral iachemia with varying degree. One of the characteristic clinical manifestations that neck rotation or specific positions of head and neck might induce the occurrence of clinical symptoms was found in 5 cases. The whole-brain coverage DSA accurately showed the location of kinking of extracranial ICA and the degree of vascular stenosis. In patients with α < 66%, 80% > α≥ 66% and α≥ 80%, clinical symptoms were found in 3 out of 5,7 out of 10 and 4 out of 6 patients, respectively. Fisher exact test revealed that the positive rates of clinical symptoms in three groups had no significant difference (P > 0. 05). Conclusion Kinking of extracranial ICA is a frequent vascular morphologic variation, and it is also a kind of potential disease. The whole-brain coverage DSA is a relatively reliable method to detect this variation.

Objective To study the cotransfection mB7-1 and mCD1D gene into pancreatic cancer cells of rats and to observe its anti-tmor responses.Methods Recombinant retroviral vectors expressing mB7-1and mCD1D gene were packaged into GP2-293 cell lines and transfected.The expressions of mB7-1 and mCD1D were detected with PCR and Western blot.The positive cells of mB7-1 and mCD1D were used to induce the anti-tumor immunity in vitro.Results Anti-tumor immunity was induced after B7-1 and CD1D positive cells were coinoculated in syngeneic mice.Furthermore,the growth of tumor was inhibited.Conclusions Cotransfection of B7-1 and CD1D could induce anti-tumor effect.This study provide a foundation for the application of B7-1 and CD1D gene therapy in tumor.