BACKGROUND:Epithelial cel s are commonly used as the seed cel in tissue engineering;however, there is stil a lack of an effective in vivo noninvasive trace technology. OBJECTIVE:To investigate the feasibility of labeling canine oral epithelial cel s with ultrasmal superparamagnetie iron oxide (USPIO) and magnetic resonance imaging (MRI) in vitro. METHODS:Oral epithelial cel s from beagles were primary cultured, and then labeled by 0.75 mg/L poly-L-lysine combined with USPIO (0, 5, 10, 25, 50 and 100 mg/L), respectively. To determine the optimal dosage, the intracel ular iron expression was identified by Prussian blue staining, and the cel viability in different groups was detected by cel counting kit-8. Final y, 2×105 labeled cel s were suspended with 1 mL PBS buffer, and were screened using 3.0 T MR on T2*WI sequences in vitro. RESULTS AND CONCLUSION:USPIO prepared with 0.75 mg/L poly-L-lysine could successful y label dog oral epithelial cel s. Prussian blue staining showed intracel ular blue spots, and the intracel ular blue spots became more with the concentration increasing and saturated at the concentration of 25 mg/L. Cel counting kit-8 indicated that the cel viability did not change when the concentration<25 mg/L. Among the T2*WI sequences, the MRI signal intensity decreased with the concentration increasing. In conclusion, canine oral epithelial cel s can be effectively labeled with USPIO making no impact on cel viability when the concentration<25 mg/L, and MRI can be used to track these labeled cel s in vitro.

Aim To investigate the relationship be-tween the depression-like behaviors of rats induced by chronically unpredictable stress( CUS) and the protein expression of tumor necrosis factor alpha( TNF-α) , in-dole-2 , 3-dioxygenase ( IDO ) and 3-hydroxyl amino acid oxygenase( HAAO) . Methods Thirty male Spra-gue Dawley( SD) rats were randomly divided into con-trol group and model group. CUS plus solitary condi-tion were used to establish the depression model. The open field test ( OFT ) and the force swimming test ( FST ) were used to evaluate the depression-like behaviors of rats ;Western blot was used to determine the protein expressions of TNF-α, IDO and HAAO in the prefrontal cortex and hippocampus of rats. Results Model group rats showed obvious depression-like be-haviors with increasing immobile time in FST ( P <0. 01) and decreasing locomotive activity in OFT( P<0. 01 ) , and up-regulating the protein expression of TNF-α, IDO and HAAO in the prefrontal cortex and hippocampus significantly ( P <0. 05 ) , compared with control group rats. Conclusion The depression-like behaviors of rats induced by CUS may be associated with the activation of IDO-HAAO pathway mediated by TNF-α.

Aim To study the role of histone acetyla-tion and its involvement in the depression-like behav-iors of rats induced by chronic unpredictable stress (CUS ). Methods Thirty male Sprague Dawley (SD ) rats were randomly divided into control group and model group.The method of solitary condition with CUS for consecutive 28 days was used to establish the rat depression model.The open-field test (OFT)and the forced swimming test (FST)were used to evaluate the depressive behaviors of rats;the real time PCR was used to detect the change of HDAC2 mRNA, and Western blot was used to determine the protein expres-sions of H3,H4,acH3 and acH4 in the prefrontal cor-tex and hippocampus of rats.Results Model group showed obvious depression-like behaviors with decrea-sing locomotive activity in OFT (P <0.01 )and in-creasing immobility time in FST (P<0.01),up-regu-lating the mRNA and protein expression of HDAC2 (P<0.0 1 ),and down-regulating the protein expression of acH3 and acH4 (P<0.01)in the prefrontal cortex and hippocampus significantly,compared with control group.Conclusion The mechanism of depressive be-haviors of rats induced by CUS may be associated with down-regulating the level of histone acetylation modifi-cation.

Objective To explore clinical and radiographic outcomes of unstable distal clavicle fractures (Neer ⅡB) fixed with lateral clavicle anatomic locking compression plate (LCP).Methods Between January 2009 and October 2010,eleven consecutive patients with unstable fractures of the distal clavicle (Neer ⅡB) were treated using lateral clavicle anatomic LCP.There were 9 men and 2 women,with the mean age of 37.2 years (range,23-43 years).The right shoulder was involved in 6 patients and the left in 5 patients.The interval between injuries to operation was 24-72 h (mean,48 h).After fracture reduction,the plate was place on superior of the distal clavicle.According to the distal fragment length,3 to 6 locking screws were carefully inserted,3 locking screws were used to fix proximal fractures.Coracoclavicular ligament was not repaired.Functional recovery of the shoulder joint was assessed using the American Shoulder and Elbow Surgeons (ASES) rating scale score.Plain radiographs of clavicles were used to assess bony union.Results All the patients were followed up for 9 to 12 months (mean,10.3 months).Solid bony union was eventually achieved in all patients.The mean ASES scores were 89.1 (range,84-91) on the injured side versus 96.2 (range,94-100) on the contralateral side.No implant-related fracture,fixation failure and rotator cuff injury occurred.Conclusion Lateral clavicle anatomic LCP fixation in the treatment of distal clavicular fractures is a reliable and simple technique.

Objective To investigate the effects of naloxone hydrechloride on neuronal cell apoptosis and cerebral edema induced by experimental brain injury.Method Animal model of brain injury was established by free-falling method of Fecney.Totally 100 SD rats were randomly divided into sham operated group(n=20),op-erated comparison group(n=40),and naloxone hydrochloride treatment group(n=40).The naloxone hy-drochloride treatment group were subdivided into four sub-groups,and naloxone hydrochloride was injected at 30 min,6 h,24 h and 48 h after brain injury respectively,while the comparison groups were injected with physiologi-cal saline at the same time point.The rats were sacrificed 7 deys after the injury.Neuronal cell apoptosis were de-tected by terminal-deoxynucleotidyl transferase mediated nick end labeling(TUNEL),and water content of brain tis-sue was examined with dry-wet methods.Data were analyzed by using spss 10.0 saftware package statistical analysis was carried out by using variance analysis.Results Gompared to the sham operated group,neuronal cell apopto-sis and water content of brain tissue were increased significantly in operated comparison group(P＜0.05).Com-pared to the operated comparison group,neuronal cell apoptosis and water content of brain tissue were decreased significantly in every naloxone hydirochloride treatment group(P＜0.05).Every sub-groups compared in naloxone hydrochloride treatment group,neuronal cell apoptosis of early injection group(30 min and 6 h after injury)were decreased significantly than late injection group(24 h and 48 h after injury,P＜0.05),but the water content of brain tissue had no difference between the early injection group and the late injection group(P＞0.05).Conclu-sions Naloxone can carry out its protective function to injuried neurecyte through alleviating neuronal cell apopto-sis and hydrecepahalus.and the effect was better as early as it used.

Objective To introduce a new minimally invasive lumbar positioning system and its positioning method as well as conduct a prospective control study on the differences in positioning time,positioning frequency and radiation exposure dose between the new positioning method and the traditional positioning method.Methods 121 patients with lumbar disc herniation combined with lumbar instability and patients with thoracolumbar vertebral fracture admitted in our hospital from May 2010 to February 2013 were randomized into two groups.68 patients in Group A had undergone the traditional positioning method before and during operation.Among the 68 patients,41 were with single-segment lesion and 27 were with two-segment lesion.53 patients in Group B had undergone the new minimally invasive lumbar positioning system before and during operation.Among the 53 patients,34 were with single-segment lesion and 19 were with two-segment lesion.There were no significant differences in gender,age,course of disease and other general information between the two groups.The positioning time,positioning frequency and radiation dose of the two groups before and during operation were compared and statistically analyzed.Results The positioning time of Group A and Group B were 8.26±3.44 min and 3.51±1.82 min respectively; the positioning frequencies were 3.57 and 1.22; the accuracy were 60.8％ and 96.2％.For the patients with single-segment lesion,the positioning time before implanting two percutaneous pedicle screws during operation were 15.12±4.69 min and 5.51±1.32 min respectively and the positioning frequency were 6.47 and 2.45.For the patients with two-segment lesion,the positioning time before implanting three percutaneous pedicle screws during operation were 24.91±7.43 min and 8.84±2.32 min respectively and the positioning frequency were 11.72 and 3.69.Moreover,the radiation dose detected at neck,chest and wrist of the surgical staff in Group A were 3.09±0.24 Gy,4.23±0.71 Gy and 5.17±0.62 Gy and that detected in Group B were 1.38±0.47 Gy,2.69±0.33 Gy and 3.21±1.05 Gy.There were significant differences in positioning time,positioning frequency and radiation dose between Group A and Group B.Conclusion The minimally invasive spine positioning system and positioning method can simplify the operative procedures and largely reduce radiation exposure,which is characterized by high positioning accuracy,short positioning time,low fluoroscopy frequency and X-ray radiation dose.

BACKGROUND: Cytoskeleton is a carrier of cell growth, and its pore caliber is one of the most important factors to affect the curative effect of tissue engineered spinal cord.OBJECTIVE: To explore the optimal pore size of poly lactic-co-glycotic acid (PLGA) scaffolds for tissue engineered spinal cord by in vitro culture of neural stem ceils (NSCs) and various pore sizes of PLGA scaffolds.METHODS: 50 μL (cell number 10~(10)/L)NSCs suspension at passage 1 was separately seeded on 200-300 pm, 400-500 μm PLGA stant for 7 days. Two sorts of tissue engineered spinal cord were constructed in vitro. Thirty rat models of spinal cord injury were established, and then assigned to 3 groups. The detect sites of these models were filled with above-mentioned spinal cord immediately, but the blank control was not treated with any material. The cells growth and proliferation implanted on PLGA were observed by phase contrast microscope and scanning electron microscope. Relative number of NSCs in two tissue engineered spinal cords was measured by MTT assay. The effects of transplantation with tissue engineered spinal cord were evaluated by the BBB scala.RESULTS AND CONCLUSION: Neural stem cells implanted on different pore size scaffolds were seen growing by phase contrast microscope and scanning electron microscope, with good histocompatibility. After 7-day coculture, absorbance was similar between 200-300 pm PLGA and 400-500 pm PLGA groups (P > 0.05). These indicated that the pore size had no effects on NSC number. At week 4 following transplantation, in the blank control group, neural function was recovered to different degrees in the 200-300 μm PLGA and 400-500 μm PLGA groups. BBB motor functional score was significantly increased (P < 0.05). The pore size of 200-300 μm utilized in fabriceting tissue engineered spinal cord has the best transplantation effect as compared to others.

Objective:To investigate the diagnostic value of diffusion weighted imaging and 1H magnetic resonance spectroscopy for the neonatal hypoxic ischemic encephalopathy (HIE).Methods:37 cases of patients with neonatal hypoxic ischemic encephalopathy admitted in our hospital were selected as the study group,another 40 healthy neonates were selected as the control group,both groups of neonates underwent diffusion-weighted imaging and 1H magnetic resonance spectroscopy,ordinary MR1 and diffusion weighted imaging findings of neonates in the study group were observed,the neonatal cerebral metabolic compounds relative concentration were observed and compared between two groups.Results:The detection rate of diffusion-weighted imaging was significantly higher compared with the ordinary MRI (P＜0.05).The relative ratio of brain metabolic compounds NAA/Cr of study group were obviously lower than those of the control group,while the Cho/Cr,MI/Cr,Glu-Glr/Cr,Lac/Cr were significantly higher (P＜0.05).Conclusion:Diffusion weighted imaging combined with 1H magnetic resonance spectroscopy could improve the diagnostic accuracy of neonatal hypoxic ischemic encephalopathy,the analysis of the concentrations of brain metabolic compounds could contribute to evaluate the severity of HIE.

Objective: To analyze the efficacy and safety of asparaginase based chemotherapy bridging autologous hematopoietic stem cell transplantation (auto-HSCT) in the treatment of 16 patients with nasal type extranodal NK/T-cell lymphoma (ENKTL). Methods: From January 2012 to June 2017, 16 patients with nasal type extranodal NK/T-cell lymphoma reached complete remission by L-asparaginase based regimens, and then received auto-HSCT. Results: ①Of the 16 patients, 12 were males and 4 females, with a median age of 35.5 (14-61) years. There were 11 patients in the first complete remission (CR1) and 5 in the second CR (CR2) before transplantation, respectively. EB virus (EBV) DNA (EBV-DNA) was negative and positive in 13 and 3 cases respectively before transplantation. ②Hematopoietic reconstitution was achieved in all 16 cases. The median time for neutrophils implantation was 12 (8-17) days, and that of platelet implantation was 15.5 (12-24) days. ③To the last follow-up, there were no transplant related deaths, 3 patients died of disease progression. The median overall survival (OS) time and progression-free survival time (PFS) were not reached. Seven patients lived with no disease progression more than 2 years. ④The OS and PFS of patients at CR₁ before auto-HSCT are better than that of patients at CR₂, but there was no statistically significant difference (P=0.162, P=0.123). There was no significant difference in OS and PFS between EBV-DNA negative and positive patients before transplantation (P=0.280, P=0.244). Conclusions L-asparaginase based regimens bridging auto-HSCT is a safe and highly effective for advanced-stage and relapsed ENKTL treatment.

Objective To study the pathological changes of the sudden death cases due to the dysplasia of the cardiac conduction system. Methods Using the newly established pathological sampling method by our research team, 26 hearts of unidentified sudden deaths excluding trauma, poisoning and diseases were collected and observed optically with H&E staining, Masson staining and immunohistochemical staining. Results Among the 26 cases, there were dysplasia in the cardiac conduction system,structural abnormalities, tissue or structure shift, fibrous cushion in the sinoatrial node and 9 cases have 2~3 abnormalities at the same time. Among the age groups from 16 to 30, 21 cases (80.8%) showed dysplasia of the cardiac conduction system. Conclusion The dysplasia of the cardiac conduction system may be one of the predominant reasons for the sudden death in young adults.