[Objective] To determine the efficacy of one-stage posterior deformity correction with transpedicular screw system and anterior radical debridement following reconstuction with titanium mesh cage for treatment of lumbar tuberculosis. [Methods]Forty-three patients with lumbar tuberculosis were treated operatively through anterior and posterior combined approach.The postoperative neurologic status (ASIA,2000),graft fusion,deformity correction and complications were observed and analyzed respectively.[Results]Forty-one patients were followed up for a duration of 24~36 months (mean 28.3 months).A solid fusion was achived in all cases.The neurologic function was improved in all patients in different grades.The mean kyphotic angle was corrected by 21.3 degrees,the angle loss was 1?~3?,the mean vertebral height was restored by 10.2 mm,the mean height loss was 2.4 mm.There was no recurrence of the tuberculosis infection.[Conclusion]One-stage posterior deformity correction with transpedicular screw system and anterior radical debridement following reconstuction with titanium mesh cage is a safe and effective method in the surgical management of lumbar tuberculosis.

Objective To observe three-dimensional structure and biological features of rat acellular spinal cord scaffold prepared by sonic oscillation and chemical extraction in order to offer an ideal scaffold for spinal cord tissue engineering research.Methods Rat spinal cord underwent acellular treatment with sonic oscillation and chemical extraction (Triton X-100 at volume fracture of 2％ and sodium deoxycholate at volume fracture of 2％) (acellular spinal cord group).In contrast with spinal cord tissue of normal rats (control group),general morphology,histology and ultramicro three-dimensional structure of acellular spinal cord scaffold were observed and aperture size,factor of porosity,water ratio,enzymolysis ratio and stability in water solution of the scaffold were also detected.Results Acellular spinal cord group showed effective removal of original cell components with factor of porosity for (94.57 ±3.45) ％ and water content for (88.62 ± 1.0) ％,and satisfactory three-dimensional structure with average aperture of 46 μm.Scaffold showed gradual degradation in enzymolysis solution and enzymolysis rate reached (69.03 ± 2.19)％ at 20 hours.Besides,scaffold showed stepwise disintegration in double distilled water and hydrolysis rate was (62.55 ± 1.70) ％ at 8 days.While,normal spinal cord showed close structure,generous neurons and myelin sheath with factor of porosity for (0.04 ± 0.02) ％ and water content for (62.4 ± 1.5) ％,and unobvious pore structure under scanning electron microscope.Normal spinal cord were degraded gradually in enzymolysis solution and enzymolysis rate was (37.62 ± 0.9)％ at 20hours.In the meantime,normal spinal cord were disintegrated gradually in double distilled water and hydrolysis rate was (40.97 ± 0.81) ％ at 8 days.Conclusions Acellular spinal cord scaffold prepared by sonic oscillation plus chemical extraction achieves complete removal of cell components,intact extracellular matrix,and satisfactory results in three-dimensional network structures,factor of porosity and water content.Also,the scaffold meets theoretical demands of tissue-engineered spinal cord scaffold and is an ideal alterative for tissue-engineered spinal cord scaffold.

Objective To construct genipin-crosslinked rat acellular spinal cord scaffolds and evaluate their enzymatic degradation rate,biomechanical properties and cytotoxicity.Methods Rat spinal cord scaffolds were decellularized by chemical extraction and chemically crosslinked with 5 g/L genipin solution.Micro-structure of the uncrosslinked and genipin-crosslinked acellular spinal cord scaffolds were observed by HE staining and scanning electron microscopy and properties of pore size,porosity,water ratio,and degradation rate in 2.5 g/L trypsin enzyme solution were examined.Ultimate tensile strength and elastic modulus of normal rat thoracic spinal cord,uncrosslinked and genipin-crosslinked acellular spinal cord scaffolds were determined on Instron mechanical testing instrument.Rat bone marrow mesenchymal stem cells were cultured in lixivium of uncrosslinked and genipin-crosslinked acellular spinal cord scaffolds and MTT assay for relative cell growth rate was test to evaluate the cytotoxicity of scaffolds.Results The uncrosslinked and the genipin-crosslinked acellular spinal cord scaffolds possessed a similar three-dimensional mesh-porous structure with a mean pore diameter about 30 μm and a porosity over 80％,but there was a statistical difference between the two groups(P ＞ 0.05).Water ratio of genipincrosslinked scaffolds was (229.7 ± 12.5) ％,far lower than (283.4 ± 11.2) ％ of uncrosslinked scaffolds (P ＜ O.05) ; genipin-crosslinked acellular spinal cord scaffolds had lower weight loss at each time point than the uncrosslinked acellular spinal cord scaffolds (P ＜ 0.05),but the stability in trypsin,ultimate tensile strength and elastic modulus of acellular spinal cord scaffolds were significantly enhanced by genipin-crosslinking (P ＜ 0.05).Furthermore,no obvious cytotoxicity was observed in the uncroslinked and genipin-crosslinked scaffolds.Conclusions Rat acellular spinal cord scaffolds present no obvious change in structure after genipin-crosslinking,but there is significant improvement in the biomechanical properties and ability against enzymatic degradation and no marked cytotoxicity.Hence,the genipincrosslinked scaffolds are promising in tissue engineering for spinal injury.

Objective: To investigate the current prevalence of latent tuberculosis infection (LTBI) among residents living in Nanchuan District, Chongqing Municipality, so as to provide the evidence for formulating LTBI control measures. Methods: The residents living in one street and one township from Nanchuan District were randomly selected using the multistage cluster sampling method during the period between January and April, 2020, and their demographic information, smoking history, history of alcohol consumption, history of contacts with tuberculosis patients and Bacillus Calmette-Guérin ( BCG ) vaccination scars were collected. The infection of Mycobacterium tuberculosis was detected using interferon gamma release assay ( IGRA ), and a positive IGRA test and exclusion of active tuberculosis was defined as LTBI. The prevalence of LTBI was descriptively analyzed among the study subjects. Results: Totally 1 000 residents were recruited, including 381 males and 619 females, with a male to female ratio of 0.62∶1. The mean age was ( 45.87±18.40 ) years. Among all participants, there were 222 smokers ( 22.20% ), 247 subjects consuming alcohol (24.70%), 62 subjects with a history of contacts with tuberculosis patients ( 6.20% ) and 904 subjects with BCG scars ( 90.40% ). A total of 198 residents were diagnosed with LTBI (19.80% prevalence), and a higher prevalence rate of LTBI was seen in men than in women ( 23.36% vs. 17.61%; χ2=4.911, P=0.027 ). The prevalence of LTBI was significantly higher in married/divorced/widowed residents than in unmarried residents ( 24.22% vs. 2.01%; χ2=49.514, P<0.001 ), and significantly greater prevalence was found in smokers than in non-smokers ( 27.93% vs. 17.48%; χ2=11.871, P=0.001 ). The prevalence of LTBI appeared a tendency towards a rise with age ( χ2trend=59.100, P<0.001 ) and body mass index ( χ2trend=9.479, P=0.002 ). Conclusions The prevalence of LTBI is high among residents living in Nanchuan District, notably among elder, male smokers with high body mass index. Risk monitoring and timely interventions are required.