Objective To explore the indications,feasibility and clinical outcome of minimally invasive laminoplasty for cervical spondylotic myelopathy (CSM) using microendoscopic technique.Methods From January 2011 to December 2013,51 patients with CSM treated by this technique in our hospital were reviewed in this study.All these patients were followed up at least 9 months.There were 28 males and 23 females with a mean age of 58 years (range 41-76 years).All patients were found to have cervical disc herniation with spinal cord compression.Among these patients,2 segments (C5-6),3 segments (C3-5/C4-6),4 segments (C3 -6) and 5 segments (C3-7) laminoplasty performed in 5,7,22 and 17 cases respectively.Therapy effect and axial symptom were evaluated according to Japanese Orthopedic Association (JOA) scores and visual analogue scales (VAS) respectively.Cervical curvature index (CCI) and range of motion (ROM) were judged by X-ray.The sagittal diameter of cervical spine,canal enlargement and bony healing were judged by CT scans.Spinal cord signal intensity changes and spinal cord decompression status judged by MRI.Statistical analysis of JOA score,VAS score,CCI and ROM were performed by paired design t test.Results The mean operative time was (1 15±21.9) min,ranging 58-139 min.The mean blood loss was (227.8±73.2) ml,ranging 110-380 ml.The followe-up time ranged 9-36 months with an average of (20±5.9) months..The mean JOA scores had improved from 8.02± 1.69 pre-operatively to 13.02± 1.48 post-operatively.The results were excellent in 17 cases,good in 28 and fair in 4.The VAS scores of axial pain significantly improved to 2.22±0.90 at the final follow-up compared with 4.96± 1.39 preoperatively.Axial symptom were excellent in 18 cases,good in 21 and fair in 12.Pre-operative was 15.40％±4.50％ and postoperative was 15.09％±4.87％,there was no significant difference.ROM of pre-operative was 40.98°±8.27° and postoperative was 38.88°±9.53°,and there was no significant difference.The sagittal diameter of the spinal canal increased 1.3-3.2 mm postoperatively with an average of (2.32±0.42) mm.A total of 204 vertebral lamina were bilaterally slotted and fixed.146 lamina were observed bone healing at the last follow-up.The bone healing rate was 71.6％.Complications such as upper limb motion dysfunction occurred in 1 case muscle strength restored after treatment of methylprednisolone sodium succinate,and little screw looseness in occurred 1 case,and non special treatment was given..Conclusion CMEL is a newsurgical approache which causes less damage to the spinous process-ligament complex and the deep extensor muscles,and the procedure can be used for CSM effectively and safely.

Objective To investigate the expression of TMPRSS4 mRNA,protein in human pancreatic cancer tissues and to explore the relationship between the expression of TMPRSS4 protein and the clinicopathologic parameters.Methods Real-time PCR and Western blotting were used to detect the expressions of TMPRSS4 mRNA and protein in 16 samples of pancreatic cancer tissues and adjacent normal pancreatic tissues.The expression of TMPRSS4 protein in 61 samples of pancreatic cancer tissues and 26 samples of adjacent pancreatic tissues and 4 samples of normal pancreatic tissues was detected by using immunohistochemistry and its relationship with clinicopathological features was analyzed.Results The expression of TMPRSS4 mRNA and protein of pancreatic cancer tissues were significantly higher than those in adjacent pancreatic tissues (9.09 ± 7.01 vs.1.27 ± 0.72; 1.223 ± 0.125 vs.0.667 ± 0.106,P ＜ 0.01 ) ;the expression rate of TMPRSS4 protein of pancreatic cancer tissues was 67.2％ (41/61),which were significantly higher than that in adjacent pancreatic tissues[3.8％ (1/26),P ＜ 0.01].There was no TMPRSS4 protein expression in normal pancreatic tissues.There was no significant correlation between the expression of TMPRSS4 protein and the age,gender,tumor location or tumor size was found.There was significant correlation between the expression of TMPRSS4 protein and the degree of differentiation,lymph node metastasis,and clinical staging (P ＜ 0.05 ).Conclusions TMPRSS4 protein is highly expressed in pancreatic cancer tissues,and the expression of TMPRSS4 is associated with the degree of malignancy of pancreatic cancer.

Objective To determine the risk factors associated with surgical site infection in closed calcaneal fractures.Methods A retrospective analysis was made on the clinical data of 312 patients with closed calcaneal fracture who had been treated by open plate osteosynthesis at our trauma centre from January 2008 to November 2014.They were 182 males and 130 females,from 18 to 75 years of age (average,44.3 years).By Sanders classification,52 cases were type Ⅱ,146 type Ⅲ,and 114 type Ⅳ.The fractures were caused by fall from a height in 159 cases,traffic accident in 97 ones,and crushing in 56 ones.All the patients received open reduction and internal fixation via a typical L-shaped lateral incision.Gender,age,cause for injury,smoking history,diabetes,interval between injury and operation,operation time and bone grafting were analyzed as possible risk factors in the study.Multivariate logistic regression was conducted for significant risk factors derived from the univariate analysis.Results The patients were divided into an infection group (28 cases,9.0％) and a non-infection group (284 cases,91.0％).The univariate analysis showed that the rate of smoking was significantly higher,the operation time significantly longer,the interval between injury and operation significantly shorter in the infection group than in the non-infection group (P ＜ 0.05).However,the logistic regression analysis revealed that operation time was the only independent risk factor for surgical site infection (P =0.005,OR =43.870).Conclusion Since operation time may be an independent risk factor for surgical site infection in closed calcaneal fracture,it is important to speed up surgery as quick as possible in control of surgical site infection as long as the surgical quality is ensured.

Objective To analysis the correlation of obstructive sleep apnea-hypopnea syndrome (OSAHS) and perihematoma edema of hypertensive cerebral hemorrhage.Methods One hundred and forty-four patients with hypertensive cerebral hemorrhage were collected and 78 of these patients were suffered from OSAHS.The patients were divided into two groups,control and OSAHS group,according to whether were accompanied by OSAHS or not.Both of the groups received the routine treatments including dehydration,reducing blood press,protecting the cerebral cells and so on.Cerebral CT scan was taken on admission.Night polymonography (PSG) was done within 24 hours of admission.Twenty-four hours and 4 days after admission,cerebral CT scan was taken again.The volumes of cephalophyma and perihematoma edema were calculated according to the results of CT scan.The changes of cephalophyma and perihematoma edema were dynamic observed.Results No difference in patients' age,sex,body mass index,serum glucose,blood lipid and so on,was observed between the two groups.The relative edema index became significantly different until 4 days after admission (0.40 ± 0.45,0.96 ± 1.35 in control and OSAHS group respectively,t =4.149,P =0.000).Similarly,the alternation edema index of OSAHS was obviously higher than that of control group only in 4 days after admission.While the analysis of the correlation between different degree OSAHS groups and edema indexes showed that at 24 hours after admission the edema volumes for different degree OSAHS groups were consistent (1.05 ± 0.65,0.84 ± 0.48,1.20 ± 0.54,1.10 ±0.40 in control,slight,moderate and severe groups respectively,F =1.061,P =0.374).At 24 hours and 4 days after admission,the edema volumes were positively correlated with the degree of OSAHS.Alternation edema index was significantly correlated with apnea hypopnea index according to the result of Pearson' s correlation analysis (r =0.652,P =0.000).Conclusion OSAHS complication can promote the progression of perihematoma edema of hypertensive cerebral hemorrhage,and the degree of edema aggravation is positive correlated to the degree of OSAHS.

Objective: To screen dynamic cardiorespiratory fitness indices for effective assessment of aerobic endurance using incremental load exercise tests. Methods: From March to November 2019, 266 volunteers who were able to understand the trial and voluntarily cooperated with the entire testing process were randomly recruited from 5 universities in Beijing. Gas metabolism and cardiac function were monitored in real time using the German Cortex Metalyzer 3B system and the US Cheetah NICOM system, and maximum oxygen uptake was measured by a linear incremental loading scheme. Aerobic endurance and dynamic cardiopulmonary function indices were selected according to the study design, and the relationship between the two indicators was analyzed using correlation and typicality correlation. Results: The absolute maximum oxygen uptake (VO 2max ), relative maximum oxygen uptake, maximum stroke volume (SV max ), and maximum stroke volume index (SVI max ) were significantly higher in males than in females, and the dynamic cardiopulmonary function index K was significantly lower than in females ( t =17.8, 10.1, 8.5, 4.3 , -6.3, P < 0.05 ). Simple correlation revealed that absolute VO 2max and relative VO 2max were negatively correlated with K and b, and absolute VO 2max and relative VO 2max were positively correlated with SV max and SVI max ( P <0.01); Both dynamic cardiopulmonary function indices were significantly correlated with aerobic endurance. Aerobic endurance indexes closely related to dynamic cardiopulmonary function were absolute VO 2max , relative VO 2max ; dynamic cardiopulmonary function indexes closely related to aerobic endurance were K, b, SV max , SVI max . Conclusion Improvement of dynamic cardiorespiratory fitness contributes to the improvement of aerobic endurance, the dynamic cardiorespiratory fitness indices K, b, SV max , and SVI max can be used as important candidates to predict the assessment of aerobic exercise capacity.

Objective To evaluate the safety and efficacy of induced hypotension and hypotension in carotid endarterectomy (CEA).Methods Data of 1 486 patients who underwent CEA in multicenters from Aug 2012 to Aug 2018 were retrospectively analyzed.After screening,a total of 1 448 patients met the inclusion criteria.Induced hypertension and hypotension was used in all thees patients.Results 87.8％ of the patients were with severe carotid stenosis.The average operative time was (51.8 ± 6.1) min,and the internal carotid artery clamping time was (11.4 ± 3.1) min.After induced hypertension,the stump pressure were higher than that before,of which 1 438 (99.3％) were greater than 50 mmHg.Monitoring of EEG oxygen saturation showed that the value of ipsilateral rSO2 was significantly lower than that of the contralateral [(56％ ± 3％) vs.(64％ ± 4％),P ＜ 0.05] before induced hypertension.After induced hypertension and clamp removal,the value of ipsilateral rSO2 was lower than that of the contralateral,but there was not significant difference (all P ＞ 0.05).Perioperative cerebral infarction occurred in 2 cases,ipsilateral cerebral hemorrhage in 1 case,contralateral cerebral hemorrhage in 1 case and myocardial infarction in 2 cases.Connclusion The technique of induced hypotension and hypotension play a temporary role in brain protection for patients undergoing CEA.This study demonstrated the safety and effectiveness of induced hypertension and hypotension technique.

Objective A 2-PSU/ RR parallel ankle rehabilitation robot was designed, and the biomechanical properties of human muscles were also analyzed, so as to study rehabilitation strategy of the ankle rehabilitation robot. Methods The actual workspace of the robot was obtained by numerical discrete search method, and the effect of structural parameter changes on the height of robot moving platform was explored. Then the human biomechanical responses such as muscle force and muscle mobility were obtained by human biomechanical simulation software AnyBody, so as to investigate the effect of moving platform height changes on muscle behavior. Results The robot could meet the demand of ankle plantarflexion/ dorsiflexion and inversion/ eversion motion. Appropriately increasing the initial inclination angle and decreasing the length of the fixed-length bar enabled the ankle rehabilitation robot to have a lower overall height. The height of the moving platform was decreased by 10 mm in turn, and the muscle force and muscle activity of the human body involved in the movement were decreased to a certain extent. Conclusions This study provides a new design solution for ankle rehabilitation, offers theoretical guidance for motion analysis of the ankle rehabilitation robot, and accelerates rehabilitation of the patients’ ankles by modifying the mechanism parameters.

BACKGROUND:Mechanical stimulation has been confirmed to promote osteogenic differentiation of bone marrow stromal stem cells,but the mechanism is unknown.Primary cilia are important mechanoreceptors and regulate various signaling pathways such as TGF-β1/BMP-2/SMAD.They are likely to be important targets for mechanical regulation of bone marrow stromal stem cells. OBJECTIVE:To investigate the effect and mechanism of fluid shear stress on osteogenic differentiation of bone marrow stromal stem cells. METHODS:Rat bone marrow stromal stem cells were divided into control group,mechanical stimulation group(fluid shear mechanics intervention by shaking table),mechanical stimulation + IFT88 silencing group(mechanical stimulation + silencing IFT88 expression with siRNA).After 24 hours of intervention,qRT-PCR was utilized to determine the expression of transforming growth factor β1 and bone morphogenetic protein 2.Western blot assay was used to detect the expression of phosphorylated SMAD2/3 protein.Immunofluorescent staining of primary cilia was conducted and morphology was analyzed. RESULTS AND CONCLUSION:Shear stress stimulation could promote the transcriptional activity of transforming growth factor β1 and bone morphogenetic protein 2 genes,and increase the expression of phosphorylated SMAD2/3 protein.After siRNA interfered with primary cilia,this mechanical response effect was significantly reduced.There was a Spearman correlation between the change ratio of the primary cilium area of bone marrow stromal stem cells and the increased ratio of transforming growth factor β1 and bone morphogenetic protein 2 gene transcription.These findings indicate that primary cilia/intraflagellar transport mediates the activation of fluid shear stress-responsive transforming growth factor β1/bone morphogenetic protein 2/SMAD signaling pathway and promotes osteogenic differentiation of bone marrow stromal stem cells.

In the paper， national and international ethical requirements and supervision on stem cell research and clinical application were analyzed after literature review. It is suggested that the development of stem cell technology should be timely tracked， prospective ethical research related to stem cells should be enhanced， and that stem cell research and clinical translation should comply with relevant international ethical guidelines and national regulations in China. In addition， it is indicated that the oversight of stem cell products and their clinical use will be continuously improved in our country.

ObjectiveTo analyze the effectiveness and safety of clinical use of different types of stem cells to provide evidence for governmental supervision of key issues in clinical utilization of stem cells. MethodsSix literature databases in China and abroad were searched for relevant literature published from January 2010 to July 2020， and a systematic review was conducted. ResultsThe study showed 72 studies concerning the effectiveness and safety of different types of stem cells in clinical utilization. Although clinical utilization of stem cells had some therapeutic effects for certain diseases， their long-term effect and safety need to be further evaluated， especially their potential risk of tumorigenicity. ConclusionTo protect the patients’ interest， physicians should fully weigh the benefits against the risks of clinical utilization of stem cells， and relevant governmental departments should strengthen supervision of ethics of clinical research and therapies involving stem cells as well as supervision of stem cell products.