Objective To explore the impact of partial or complete rupture of the tibiofibular syndesmosis on the biomechanical properties of the ankle joint.Methods Six fresh cadaveric specimens of adult ankle were used for creation of 3 models of tibiofibular syndesmosis.In model A,the medial and lateral ligaments of the ankle joint and the tibiofihular syndesmosis were intact.In model B,only the anterior lower tibiofibular ligament was broken.In model C,all inferior tibiofibular ligaments were broken.The 3 models were tested with an electronic pressure sensor in a BOSE material testing machine respectively at 5 positions:10° dorsal extension,20° inversion,20° eversion,20° plantar flexion,and neutral position.The peak values and locations of the compressive stresses of the 3 models at 5 positions were recorded.All the data were collected and analyzed using IBM SPSS 22.0 statistical software.Results Model A exhibited the smallest average stress at all the 5 positions,followed by model B and model C,with significant differences between groups (P ＜ 0.05).The locations of main compressive stress at the neutral position,10° dorsal extension,and 20° plantar flexion in model B and model C tended to expand outwards compared with model A,especially in model C.Conclusions Rupture of the anterior lower tibiofibular ligament and inferior tibiofibular ligaments may increase the compressive stress on the ankle joint,especially rupture of the inferior tibiofibular ligaments.The location of main compressive stress tends to expand outwards when the anterior lower tibiofibular ligament and inferior tibiofihular ligaments are broken,especially the inferior tibiofibular ligaments.

Objective To investigate the mechanism of recombinant human growth hormone(rhGH) in articular cartilage defect repair in vivo.Methods The cylindrical,full-thick articular cartilage defects,(3.5 mm) in diameter,were made in the knee joints of 25 rabbits.rhGH of 0.1 U/kg was injected into the right knee joints 3 times a week for 4 weeks and equal volume of physiological saline to the left knee joints as control.The animals were killed respectively in 4,6,8,12,24 weeks,and the macroscopic,histologic and ultrastractural examinations were performed.Results The repairing process in experimental group was faster and better than that in the control.In the experimental groups,the defect was filled on week 4,the regenerated cartilage mainly in the shallow region and fibrous tissue in the deep region;on week 24,the regenerated tissue was morphologically close to the neighbour normal cartilage,hard to differentiate by macroscopy;Light microscopy showed the defect recovered to normal cartilage structure and the electron microscopy showed a large quantity of mature cartilage cells.In the control groups,the defect was of shallow introcession,mainly of fibrous tissue.The histological examination showed the significant difference between experimental and control groups(P

BACKGROUND: Magnetic resonance imaging(MRI)is considered safe for diagnosis of meniscus injury,having accuracy as high as 80% to 100%.However,it is found that there are some false positive and false negative in the clinic.OBJECTIVE: Through assessment of menisci injuries of the knee using magnetic resonance imaging and arthroscopy,to investigate MRI manifestation in different types of meniscal injuries.METHODS: A study from January 2003 to December 2008 was performed in 212 patients with knee injury undergoing preoperative MRI.Radiograph was read by physicians who had a senior professional title from radiology and orthopaedics departments,and meniscus damage and damage morphology were predicted.Arthroscopy was conducted by chief physician.Meniscus damage during surgery was considered as gold standards.The accuracy of them was compared.The statistics of accuracy of MRI diagnosis was gathered.RESULTS AND CONCLUSION: Totally 212 patients and 230 knees were included,and a total of 215 knees of meniscus injury were described by MRI diagnosis and 213 knees of meniscus injury were proven by arthroscopy.The sensitivity,specificity and accuracy of MRI diagnosis of meniscus injury respectively were 93.5%,64.7%,93.0%.It is found that the sensitivity of MRI diagnosis of bucket-handle damage is high.MRI is easy to miss diagnosis in a light meniscus posterior horn tear,and resuts are more false positive in lateral meniscus injury.It needs arthroscope operation or further surgery in some condition such as gradeⅢ type injury,meniscus displacement after injury and articular capsule separation,which indicates instable meniscus.

BACKGROUND: The tissue engineered corneal epithelium can be constructed with limbal stem cells of healthy rabbit cornea cultured in vitro, and its transplantation may promote the repair and healing of corneal alkaline burn.OBJECTIVE: To probe the effect and opportunity of treating corneal alkaline bum by tissue-engineered corneal epithelium transplantation.DESIGN, TIME AND SETTING: Controlled observational animal experiment was performed in the Department of Experimental Animal at the First Affiliated Hospital of Chinese PLA General Hospital between July 2007 and June 2008.MATERIALS: Twenty-one New Zealand female white rabbits, weighing 2.0-2.5 kg, were divided into control group (n=8, 16 eyes) and transplantation group (n=13, 26 eyes) at random. The transplantation group was further assigned into early transplantation group at 1 day (n=2, 4 eyes), 3 days (n=3, 6 eyes), 6 days (n=6, 12 eyes), and 9 days (n=9, 18 eyes); and mataphase transplantation group at 14 days (n=3, 6 eyes).METHODS: The tissue-engineered corneal epithelium was prepared on 21 rabbits with limbal stem cells cultured in vitro, and reforming comeel alkaline burn models of double eyes were induced by 1 mollL NaOH. The autotogous or allogenic tissue-engineered comeal epithelium transplantation was conducted on early time points (1, 3, 6, 9 days) or metaphase (14 days) after alkaline burning. In the control group, the burns were observed for 4 consecutive weeks.MAIN OUTCOME MEASURES: The ocular surface integrity and histopathology in the transplantation group and control group were observed on several time points within 4 weeks.RESULTS: At 1 weak after corneal alkaline burning, large corneal epithelial dasquamation occurred, 72% incidence of epithelial desquamation or corneal ulcer at 2 weeks, and continued to 4 weeks, while only 25% were observed at 4 weeks in transplantation group, most gained ocular surface integrity; cell infiltration and vascularization of corneal stroma had not bean suppressed in metaphase transplantation group, while they were suppressed obviously in the deep comeal stroma in early transplantation groups; Within 4 weeks, immunological rejection induced by allogenic transplantation was not greater than that of autologous transplantation.CONCLUSION: Cultivated autologous or allogenic tissue-engineered corneal epithelium transplantation could recover ocular surface integrity as soon as possible, and the effect of early transplantation surpasses that of mstaphase.

Objective To detect the expression level of miRNA-575 by pancreatic cancer stem cells.Methods Pancreatic cancer cell lines were cultured with serum-free medium.The cancer stem cells were obtained and their characteristics were observed with an invasion assay,a xenograft experiment,and flow cytometry analysis.Moreover,qRT-PCR was used to detect the expression of miR-575.Results A small subpopulation of cells in both ASPC-1 and PANC-1 cells survived and formed spheres in the absence of serum.The mean number of migrated cells of PANC-1 and ASPC-1 spheres was (147.3±18.6) cells and (113.2±12.9) cells.Therefore,the spheres have higher invasive ability compared with those of parental cells.As few as 5 × 105 cells in PANC-1 and ASPC-1 spheres could initiate a xenograft tumor in NOD/SCID mice,which suggested the tumorigenicity of the spheres was 100 times those of parental cell lines.The percentages of CD24+CD44+ in spheres were 0.38％-0.43％ and 4.91％-5.21％,which showed increased expression compared with ASPC-1 and PANC-1 cell lines (P＜0.05).The expression of miR-575 in spheres was 3.71 and 3.83 times its expression in cell lines ASPC-1 and PANC-1 respectively (P＜0.05).Conclusions Pancreatic cancer cell spheres may be a source for collecting cancer stem cells in a serum-free medium culture,and MiR 575 may play an important role in regulating the biological characteristics of pancreatic cancer stem cells.

Clinical data of 4 patients with chronic obstructive pulmonary disease who underwent allogenic single-lung transplantation were retrospectively analyzed. All cases received corpse donor lungs. One case with diffuse emphysema underwent right lung transplantation. and 3 received left lung transplantation. including one underwent fight lung volume reduction during surgery and 2 cases underwent right lung volume reduction post-transplantation. The inductive treatment with daclizumab or antithymocyte globulin was done and the rejection was prevented with Tacrolimus. mycophenolate and prednisone. The surgery was successfulin 4 cases. One case developed acute rejection on the fifth day post-transplantation. and controlled using methylprednisolone. Two cases discharged successfully, of whom one lived more than 2 years. Two cases died 74 days and 77 days after lung transplantation. respectively.

Objective To investigate the value of nasal continuous positive airway pressure (NCPAP) in the treatment of severe pneumonia. Methods The clinical data of 59 severe pneumonia infants who received NCPAP preferential ventilation strategy were retrospectively analyzed. Results After treatment, 50 infants were effective and 9 infants were ineffective. Before treatment, the age, RR, HR between effective group and ineffective group had no significant differences (P>0.05). But the levels of PaCO2, PaO2/FiO2 in ineffective group were significantly higher than those in effective group and the level of PaO2 in ineffective group was significantly lower than that in effective group (P<0.05). In effective group, the levels of PaO2 and PaO2/FiO2 were significantly increased after treatment for 1, 12 and 24 h, and the levels of PaCO2, RR and HR were significantly decreased (P<0.01). Conclusions NCPAP preferential ventilation strategy can reduce the use of invasive mechanical ventilation, improve oxygenation, ease dyspnea and make vital signs stable.

Objective To explore the mechanisms of mesenchymal stem cells (MSC) in the treatment of concanavalin A (ConA)-induced acute immune liver injury in mice.Methods MSC were isolated and cultured from bone of the four limbs of three-week-old C57BL/6 mice.The specific surface markers were identified and osteogenic,adipogenic differentiation ability were tested.A total of 15 six to seven-week old C57BL/6 mice were divided into control group,MSC treatment group and phosphate buffer saline (PBS) treatment group,five mice in each group.The mice of MSC treatment group was injected through tail firstly with ConA and then MSC,PBS treatment group was injected through tail firstly with ConA and then PBS,control group was injected through tail with PBS twice.The mice were sacrificed in 14 to 16 hours after injection.The level of alanine aminotransferase (ALT),aspartate transaminase (AST) in peripheral blood were detected and the pathological change in liver tissue was scored by Knodell score system.Activation rate of splenic CD4+ T cells and the proportion changes of T hepler cell (Th)1,Th2,Th17 and regulatory T cells (Treg) were detected by flow cytometry and the ratio of Th17/Treg was calculated.The levels of tumor necrosis factor α (TNF-α),interferon (IFN)-γ and interleukin (IL)-4 in peripheral blood were detected by enzyme linked immunosorbent assay (ELISA).Independent-sample t test was used for comparison between groups of measurement data.Results ALT,AST and Knodell score of MSC treatment group was (174.2± 46.9) U/L,(185.6± 71.6) U/L and 3.4±1.3,respectively,which were better than those of PBS treatment group ((647.0± 118.0) U/L,(749.0± 104.0) U/L and 5.2 ±0.8,respectively),and the differences were statically significant (t =8.33,9.98 and 2.55,all P＜0.05).The activation rate of splenic CD4+ T cell of PBS treatment group was (26.10±2.17) ％,the proportion of Th1 and Th2 in CD4+ T cell was (5.81±0.79) ％ and (5.98± 1.22)％,the ratio of Th17/Treg was 0.29±0.03,the levels of TNF-α,IFN-γ and IL4 in peripheral blood were (1 281.95±88.61) U/L,(1 838.66±196.91) U/L and (1 192.36±163.94) U/L,which were higher than those of control group ((13.74±1.59)％,(1.35±0.17)％,(2.13±0.17)％,0.15± 0.05,(21.71±2.50) U/L,(11.84±1.28) U/L and (24.46±3.96) U/L),and the differences were statistically significant (t=10.26,12.37,7.02,5.30,31.79,15.93 and 20.75,all P＜0.01).There was no statistically significant difference in the activation rate of splenic CD4+T cell between MSC treatment group and PBS treatment group ((26.20±3.09)％ vs (26.10±2.17)％,P＞0.05).However,in MSC treatment group,the proportion of Th1 and Th2 in CD4+ T cell ((1.83±0.52) ％ and (2.75±1.06％)),the ratio of Th17/Treg (0.18±0.02) and the levels of TNF-α,IFN-γ and IL-4 in peripheral blood ((760.71± 73.19) U/L,(742.49±76.46) U/L and (825.76±101.74) U/L) significantly decreased compared with those of PBS treatment group,and the differences were statistically significant (t=9.45,4.48,6.41,10.14,5.56 and 10.22,all P＜0.01).There was no significant difference in the ratio of Th17/Treg between MSC treatment group and control group (P＞0.05).Conclusions The therapeutic effects of MSC on ConA induced acute immune liver injury were through influence splenic CD4+ T cell subsets by decreasing the proportion of Th1 and Th2 and then declining the levels of secreted cytokines such as TNF,IFN-γ and IL-4 in peripheral blood,increasing the proportion of Treg and decreasing the proportion of Th17 and keeping the balance of Th17/Treg.

The various mechanisms of kyphosis of the spine and the differential diagnosis of related diseases to guide the selection of appropriate surgical timing, correct spinal osteotomy and reasonable surgical methods. The 24 patients with kyphosis from January 2016 to January 2018 were diagnosed. All patients underwent kyphosis orthopedics, mainly spinal wedge osteotomy, to obtain orbital purpose by wedge osteotomy. The indexes of the spine form, activity, and pain were observed after operation. Of the 24 patients with kyphosis, 5 patients were treated conservatively, and the symptoms of kyphosis were effectively relieved. 19 patients underwent kyphosis orthopedic surgery, and the anterior spine and posterior closed osteotomy. The patients recovered well after surgery and were followed up regularly. The treatment of high anterior spine and posterior closed osteotomy in patients with kyphosis has accurate surgery effect. There are no complications such as pain and internal fixation during the regular follow-up.

Objective To report the experience of lung transplantation with size reduced graft lung.Methods Four cases receiving lung transplantation with size reduced graft lung were analyzed retrospectively.In case 1,left lung transplantation combined with contra-hteral lung volume mduction.In case 2,right lung transplantation Wag individually performed with partially msecfion of upper lobe of graft lung.In case 3.bilateral sequential lung transplantation wag performed using graft lung with partially resection of bilateral upper lobes.In the remained ease,bilateral sequential lung tansplantation was performed using graft lung with resection of right lower lobe.Results All the size reduced graft lungs had good functions during the peri-operation period.Case 1 and case 2 still survived without obvious complication.Case 3 experienced temporary air leak on the 5th day postoperation and cured by water seal drainage but died of abrupt bronchorrhea due to aspergillus infection on the 32th day postoperation.The last cage experienced smoothly recovery excepted fatal virus pneumonia 2 months postopemtion.Conclusion Size reduced graft lungs can be successfully used for transplantation.