Diagnostic value of enzyme-linked immunospot assay using CFP10/ESAT6 fusion protein as antigen in spinal tuberculosis.

OBJECTIVE: To establish a method of detecting spinal tuberculosis (TB) infection by enzyme-linked immunospot (ELlSPOT) assay and evaluate the value of CFP10/ESAT6 fusion protein for diagnosis of spinal TB. METHODS: Suspected spinal TB patients were prospectively recruited in two hospitals (First Affiliated Hospital of Guangzhou University of Traditional Chinese Medicine; Nanfang Hospital, Southern Medical University) from May 2012 to December 2013. Data on clinical characteristics of the patients and conventional laboratory results were collected. Compare and analyze the positive detection rate in spinal TB diagnosis by different methods including ELISPOT detection and conventional detection methods. RESULTS: 47 patients with spinal TB had available biopsy or surgical specimens for histopathological examination and 41 specimens had pathological features consistent with a diagnosis of TB infection. Among the spinal TB patients and non-TB disease patients,the overall sensitivity, specificity, positive predictive value, and negative predictive value of the ELISPOT assay in spinal TB diagnosis were 82.7%,87.2%,89.6%, and 79.1%,respectively; the 4 indexes of the PPD skin test were 61.5%, 46.2%, 60.4%, and 47.4%, respectively;those of the antibody detection were 55.8%, 61.5%, 65.9%, and 51.1%. The positive rate of ELISPOT was significantly higher than those of PPD skin test and antibody detection test (82.7% vs. 61.5%, Χ² =5.786, P=0.016; 82.7% vs. 55.8%, Χ² =8.847, P=0.003), but not significantly different from the positive rate of pathological examination (82.7% vs. 87.2%, Χ² =0.396, P=0.529). Moderate agreement was found between pathological examination and the ELISPOT assay (87.2%, Κ=0.498, P=0.001). CONCLUSION: With high sensitivity and specificity, the ELISPOT assay using CFP10/ESAT6 fusion protein as antigen is an effective technique for auxiliary diagnosis of spinal TB.

Design and finite-element evaluation of a versatile assembled lumbar interbody fusion cage.

INTRODUCTION: When an interbody cage is inserted into a human being's lumbar spine, not only the design, but also the material used is considerably crucial, particularly when minimally invasive lumbar fusion (MILIF) approaches are considered. The purpose of this study was to design a multi-function cage (either for MILIF or open lumbar interbody fusion) and also to evaluate the strength of the design based on a finite-element model analysis. METHOD: Three-dimensional finite-element models that were instrumental in the reproduction of post-operative conditions under which different cages, such as assembled lumbar interbody fusion cages (ALIFC) and the separated ones, could be examined and traced after implantation were developed. Simulations were run to realize various loading conditions including axial compression, flexion, extension, lateral bending and rotation under a constant compressive preload. Meanwhile, the evaluation results derived from FEMs data focused on endplate stress distribution, peak stress of von Mises and stress of cage. Stress distributions on the bone surface were evaluated and discussed as well. RESULTS: The consequences of cage insertion, high strains and stresses, were concentrated in the areas where the cage and endplate were in contact with each other. Simultaneously, contact stresses around the implants seemed to be concentrated around the periphery of the device. After implantation of ALIFC, the stiffness of the new cages was similar to that of traditional cages in an assemble condition, according to the biomechanical data dealing with FEM. Once a separated cage was in the place of an assembled cage, the stresses would get symmetrically distributed in the lateral areas of the endplate and decrease significantly at the center where the separated cage was not in contact with the endplate. The stress of the cage was going to be high once being rotating; most significant difference of stresses distribution due to the alternative choice has been found in the state of rotation. On comparison of peak von Mises stresses on the endplates in the new cage, the stresses were symmetrically distributed in the lateral areas of the endplate when a separated cage was used in place of an assembled cage. CONCLUSION: The new cage was more advantages with regard to endplate stress distribution, peak stress of von Mises and stress of cage than the assembled state. ALIFC can provide sufficient primary stability for lumbar intervertebral fusion and the new cage may be regarded as a suitable device for load-bearing implantation.

MicroRNA expression profile of bronchioalveolar stem cells from mouse lung.

Increasing evidence has suggested that bronchioalveolar stem cell (BASC) is the progenitor cells of lung cancer stem cells. However, the mechanisms by which self-renewal of BSACs is controlled and how BASCs turn into cancer stem cells still remains to be unknown. In the present study, we successfully isolated bronchioalveolar stem cells (BASCs) from mouse lung using FACS. These BASCs were characterized by clonal growth, self-renewal and high capacity for differentiation, suggesting that these BASCs are indeed stem cells. We investigated the microRNA (miRNA) expression profile of these BASCs using miRNA array and quantitative RT-PCR. We discovered that BASCs possessed a unique miRNA profile, with altered expression of several microRNAs, such as miR-142-3p, miR-451, miR-106a, miR-142-5p, miR-15b, miR-20a, miR-106b, miR-25, miR-486, in BASCs compared to control cells. Our results suggest that microRNAs might play important roles in maintaining the self-renewal capacity of BASCs, and suggest the intriguing possibility that aberrant expression of microRNAs could involved in turning BASCs into lung cancer stem cells.