BACKGROUND:A large number of studies have shown that adult stem cels derived from multiple tissues are available to differentiate towards nucleus pulposus-like celsin vitro. It is unclear whether mesenchymal stem cels derived from nucleus pulposus tissues have the ability to differentiate towards nucleus pulposus-like phenotypes induced by transforming growth factor-beta 1. Up to now, there are few reports on the difference between the differentiation ability of mesenchymal stem cels derived from nucleus pulposus tissues and adipose-derived mesenchymal stem cels. OBJECTIVE:To compare the ability of mesenchymal stem cels derived from nucleus pulposus tissues and adipose-derived mesenchymal stem cels differentiating into nucleus pulposus-like cels under induction of transforming growth factor-beta 1. METHODS:The groin fat tissue and the coccygeal spine of rats were taken respectively to isolate and culture mesenchymal stem cels derived from nucleus pulposus tissues and adipose-derived mesenchymal stem cels by mechanical enzyme digestion method. Flow cytometry was employed to detect the expression of CD105, CD90, CD29, CD45, CD44, CD34, and CD24 of both two kinds of stem cels. Mesenchymal stem cels derived from nucleus pulposus tissues and adipose-derived mesenchymal stem cels were divided into complete induction group (complete induction medium with transforming growth factor-beta 1), incomplete induction group (complete induction medium without transforming growth factor-beta 1) and control group(DMEM/F12 containing 10% fetal bovine serum and 100 mg/L penicilin/streptomycin), respectively. After 14 days of culture, real-time PCR was used to detect the expression of colagen type II, Aggrecan and SOX-9 in each group. RESULTS AND CONCLUSION:CD105, CD90, CD29 expressed positively and CD45, CD44, CD34, CD24 negatively in both two kinds of stem cels. After 14 days of induced differentiation, the expressions of colagen type II, Aggrecan and SOX-9 in the two kinds of cels were significantly higher in the complete induction groups than in the control groups (P < 0.05). Under the induction of transforming growth factor-beta 1, the expression of colagen type II, Aggrecan and SOX-9 in mesenchymal stem cels derived from nucleus pulposus tissues was significantly higher than that in adipose-derived mesenchymal stem cels (P < 0.05). These findings suggest that both two kinds of mesenchymal stem cels have the ability to differentiate towards nucleus pulposus-like cels induced by transforming growth factor-beta, and mesenchymal stem cels derived from nucleus pulposus tissues may be more suitable as seed cels for nucleus pulposus tissue engineering research.

Strains from the cellulose-containing environment were collected. Primary screening(by filter-paper Hutchison solid culture medium and sodium carboxymethylcellulose solid culture medium) and reelection(by filter-paper inorganic salt culture medium and sodium carboxymethylcellulosc Congo red coltnre medium) indicated that five strains obtained were best suited for high performance cellulose degradation. Determination of sodium carboxymethylcellulose activity(CMCA) and filter paper activity(FPA) was accomplished for each of the five. The strongest of the five in CMCA and FPA was applied to the production of cellulose bioethanol by separate hydrolysis and fermentation(SHF) and simultaneous saccharification and fermentation(SSF) respectively.

This research adopted silt as the sample,and the five highest hydrogen production performing strains contained in the sample were isolated. The strain whose hydrogen production was the highest was identified as Enterobacter cloacae by the analysis of 16S rDNA sequencing and comparison. It is showed by Plackett-Burman Experimental Design that only glucose,citric buffer and reducing agent had significant effects on hydrogen production by Enterobacter cloacae FML-C1. The path of steepest ascent was undertaken to approach the optimal response region of those three factors. Central Composite Design(CCD) and Response Surface Methodology(RSM) were employed to investigate the interaction of the variables and to ascertain the optimal values of the factors,which finally led to the maximum hydrogen production(VH2) . The theoretical optimal medium conditions were:glucose 21.5 g/L,citric buffer 13.6 mL/L,reducing agent10.0 mL/L. The five tentative tests matched this model well. The final VH2 was up to 2347.4 mL/L,which was 127.42% enhanced in comparison to the original. The result shows that PB experiment design and RSM analytical method work well in selecting factors which have significant influences on the hydrogen production and,moreover,achieve the ideal optimal result.

Objective To investigate the selection of surgery and clinical outcomes of upper cervical injuries.Methods 25 upper cervical injury patients were involved in this retrospective study from November 2011 to June 2014.Including 20 males and 5 females with mean age of 37.1 years old (range,14-55 years old).Individual operation methods were based on the comprehensive evaluation of specific situations including the clinical manifestation,the type of the injuries and the imaging data.HaloVest distraction was applicated before operation.The surgery by anterior approach were performed for 7 patients and posterior approach were performed for 18 patients.Preoperative and postoperative American Spinal Injury Association (ASIA) grade and Functional Independence Measurement (FIM) score were studied to evaluate the nerve functional restoration.Imaging data before and after the operation were contrasted to evaluate the reduction of the fracture,the bone union,the fusion of the bone graft and the condition of the internal fixation.Wilcoxon Singed Rank Test was applied to compare the FIM score between pre-operation and last follow-up.Results 15 patients presented neurological function deficit because of cervical spinal cord compromise.All cases were followed up for 6-35 months (mean 18.2 months),showing good clinical and radiological effects.Solid fusion was obtained in all patients among 3-12 months.The ASIA grade improved by an average of 1.1 (6 months after operation) and 1.2 (12 months after operation).There was significant difference in FIM score between pre-operation and last follow-up.One patient got cerebrospinal fluid leakage.Conservative treatment was implemented with the Trendelenburg position,rehydration fluids and so on.Removal of drainage tube 8 days later when the drainage was less than 30 ml/24 h.No incision infection,cerebrospinal fluid leakage,migration or breakage of internal fixation was observed at the last follow-up.Conclusion The type of upper cervical injuries are complicated,the characteristics of fracture,dislocation and nerve injury in different patients are different.The specific situation should be evaluated comprehensively to make individual operation methods.The success of the operation requires the proficiency of the anatomic basis,the biomechanical characteristics,precise entrance point and direction in operation,appropriate diameter of the screw and suitable depth of the screw road.

Objective To report a case presented with atypical clinical and radiological appearance in the early stage and finally pathologically confirmed as chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids ( CLIPPERS) , aiming to improve the understanding of the disorder. Methods The clinical, imaging, laboratory and pathological features as well as treatment and prognosis of a pathologically confirmed CLIPPERS patient with repeated relapsing-remitting course and stepwise progression in nine years were retrospectively analyzed. Results There were five relapsing-remitting processes in total clinical course of nine years. The clinical and radiological appearance was atypical in the early stage. At the first attack, the patient presented with fever, headache, altered consciousness and epileptic seizure. In the following courses, the patient presented with ataxia, blurred vision and limb weakness. Brain MRI (2006-2009) showed multiple abnormal signals including supratentorial white matter, pons and cerebellum with patchy gadolinium enhancement. Treatment with steroids resulted in a favorable clinical and radiological improvement. The symptoms of this attack included limb weakness, blurred vision, dysdipsia and dysarthria. Physical examination showed cognitive dysfunction, multiple cranial nerves injuries and bilateral pyramidal signs. Brain MRI showed multiple abnormal signals involved pons and cerebellum predominantly as well as supratentorial white matter with punctate gadolinium enhancement peppering the pons and cerebellum. A characteristic predominantly T lymphocytic perivascular infiltration was seen on brain biopsy. Both the imaging and histological findings were consistent with the CLIPPERS features. High-dose steroids treatment was given and obvious clinical and radiological improvements were observed. After discharge, steroids were reduced slowly combined with the use of immunosuppressant to avoid relapse of the disorder. Conclusions There is heterogeneity in clinical manifestations of CLIPPERS with repeated relapsing-remitting course and imaging presentations are sometimes atypical in the early stage, which leads to the misdiagonsis and missed diagnosis. Distinctive pathology is the “gold standard” for definite diagnosis. The nosological position of CLIPPERS is still unclear. Repeated relapse-remitting leads to secondary cerebral atrophy and degeneration, with the risk of progressing to primary central nervous system lymphoma. Early and vigorous steroids treatment with continuing maintenance immunotherapy results in the decreased relapse and best long-term prognosis. The neurologist should strengthen the understanding of CLIPPERS for early correct diagnosis and treatment aiming to reduce the functional disability.

To study and optimize the fermentation parameters for expressing human-like collagenⅡduring E. coli high-density fermentation. The effects of pH, temperature, dissolved oxygen and induction instant on the cell growth and human-like collagenⅡproduction were investigated to optimize the fermentation conditions. The results demonstrated that the following conditions were beneficial for cell growth and foreign gene expression, controlling pH in phase induction at 6.8 and initial pH at 6.5, maintaining fermentation temperature and dissolved oxygen concentration was controlled at 34?C and 20% respectively, and implementing induction at the later logarithmic growth phase. Under the optimized condition, the cell density and human-like collagenⅡyield could reach 88.4 g/L and 14.2 g/L, respectively.

Objective:It explores critical issues of discounting in health technology assessment to provide a reference for improving discount rates in China.Methods:Based on literature review and empirical cases,it compares and analyzes the practical experience of the UK and Canada and the basis for discount rate setting in pharmacoeconomic evaluation and guidelines of various countries.Results:It is found that the social time preference and social opportunity cost approach provide research perspectives for discount rate calculation.How-ever,there are differences in the choice of discounting in international guidelines and pharmacoeconomic evaluation practices,which may reflect differences among countries regarding economic environment,healthcare systems,and values.Conclusion:It calls for more basic research on discounting and suggests the formulation of discount rates that align with our China's economic environment to provide deci-sion-makers with a reliable information foundation.

Objective:It explores critical issues of discounting in health technology assessment to provide a reference for improving discount rates in China.Methods:Based on literature review and empirical cases,it compares and analyzes the practical experience of the UK and Canada and the basis for discount rate setting in pharmacoeconomic evaluation and guidelines of various countries.Results:It is found that the social time preference and social opportunity cost approach provide research perspectives for discount rate calculation.How-ever,there are differences in the choice of discounting in international guidelines and pharmacoeconomic evaluation practices,which may reflect differences among countries regarding economic environment,healthcare systems,and values.Conclusion:It calls for more basic research on discounting and suggests the formulation of discount rates that align with our China's economic environment to provide deci-sion-makers with a reliable information foundation.

Objective:It explores critical issues of discounting in health technology assessment to provide a reference for improving discount rates in China.Methods:Based on literature review and empirical cases,it compares and analyzes the practical experience of the UK and Canada and the basis for discount rate setting in pharmacoeconomic evaluation and guidelines of various countries.Results:It is found that the social time preference and social opportunity cost approach provide research perspectives for discount rate calculation.How-ever,there are differences in the choice of discounting in international guidelines and pharmacoeconomic evaluation practices,which may reflect differences among countries regarding economic environment,healthcare systems,and values.Conclusion:It calls for more basic research on discounting and suggests the formulation of discount rates that align with our China's economic environment to provide deci-sion-makers with a reliable information foundation.

Objective:It explores critical issues of discounting in health technology assessment to provide a reference for improving discount rates in China.Methods:Based on literature review and empirical cases,it compares and analyzes the practical experience of the UK and Canada and the basis for discount rate setting in pharmacoeconomic evaluation and guidelines of various countries.Results:It is found that the social time preference and social opportunity cost approach provide research perspectives for discount rate calculation.How-ever,there are differences in the choice of discounting in international guidelines and pharmacoeconomic evaluation practices,which may reflect differences among countries regarding economic environment,healthcare systems,and values.Conclusion:It calls for more basic research on discounting and suggests the formulation of discount rates that align with our China's economic environment to provide deci-sion-makers with a reliable information foundation.