Qiang Zhou

MicroRNA-24 inhibits osteosarcoma cell proliferation both in vitro and in vivo by targeting LPAATβ.

Lysophosphatidic Acid Acyltransferase β (LPAATβ) may be critically involved in osteosarcoma cell proliferation. However, the comprehensive mechanisms responsible for regulation of LPAATβ in osteosarcoma cells remain unclear. This study found that enhanced LPAATβ expression was correlated with osteosarcoma cell proliferation. MiR-24, targeted to LPAATβ, was down-regulated in osteosarcoma cells. Overexpression of miR-24 down-regulated LPAATβ expression in osteosarcoma cells. Specifically, overexpression of miR-24 inhibited osteosarcoma cell proliferation, however, such effect was blocked when LPAATβ activity was inhibited. In conclusion, our study indicates that miR-24 is reduced in osteosarcoma cells, contributing to up-regulation of LPAATβ and resultant osteosarcoma cell proliferation.

A posterior versus anterior surgical approach in combination with debridement, interbody autografting and instrumentation for thoracic and lumbar tuberculosis

PurposeThe purpose of this study was to compare posterior and anterior surgical approach in combination with debridement, interbody autografting and instrumentation for thoracic and lumbar tuberculosis. These approaches were compared in terms of the operation duration, intraoperative blood loss, bony fusion, intraoperative and postoperative complications, neurological status and the angle of kyphosis.MethodsForty-seven patients with thoracic and lumbar tuberculosis who underwent either the posterior or the anterior approach in combination with debridement, interbody autografting and instrumentation from January 2004 to March 2010 were reviewed retrospectively. In group A (nu2009=u200925), the posterior approach was combined with debridement, interbody autografting and instrumentation. In group B (nu2009=u200922), the anterior approach was performed in addition to debridement, interbody autografting and instrumentation.ResultsAll cases were followed up for 12–62xa0months. There was no statistically significant difference between groups in terms of the operation duration, intraoperative blood loss, bony fusion, intraoperative and postoperative complications, neurological status and the angle of kyphosis (pu2009>u20090.05). Good clinical outcomes were achieved in both groups.ConclusionsThe posterior approach combined with debridement, interbody autografting and instrumentation is an alternative procedure to treat thoracic and lumbar tuberculosis. The posterior approach is sufficient for lesion debridement. In addition, the posterior approach can maintain spinal stabilisation and prevent loss of corrected vertebral alignment as effectively as the anterior approach.

Successful Development of Small Diameter Tissue-Engineering Vascular Vessels by Our Novel Integrally Designed Pulsatile Perfusion-Based Bioreactor

Small-diameter (<4 mm) vascular constructs are urgently needed for patients requiring replacement of their peripheral vessels. However, successful development of constructs remains a significant challenge. In this study, we successfully developed small-diameter vascular constructs with high patency using our integrally designed computer-controlled bioreactor system. This computer-controlled bioreactor system can confer physiological mechanical stimuli and fluid flow similar to physiological stimuli to the cultured grafts. The medium circulating system optimizes the culture conditions by maintaining fixed concentration of O2 and CO2 in the medium flow and constant delivery of nutrients and waste metabolites, as well as eliminates the complicated replacement of culture medium in traditional vascular tissue engineering. Biochemical and mechanical assay of newly developed grafts confirm the feasibility of the bioreactor system for small-diameter vascular engineering. Furthermore, the computer-controlled bioreactor is superior for cultured cell proliferation compared with the traditional non-computer-controlled bioreactor. Specifically, our novel bioreactor system may be a potential alternative for tissue engineering of large-scale small-diameter vascular vessels for clinical use.

Management of drug-resistant spinal tuberculosis with a combination of surgery and individualised chemotherapy: a retrospective analysis of thirty-five patients

PurposeDrug-resistant tuberculosis is a major public-health concern globally and can be difficult to manage clinically. Spinal tuberculosis is the most common manifestation of extrapulmonary tuberculosis. However, there have been few reports on the topic of drug-resistant spinal tuberculosis. The aim of this study was to investigate the clinical characteristics and drug susceptibility patterns and the outcomes of management with a combination of surgery and individualised chemotherapy, for drug-resistant spinal tuberculosis.MethodsWe retrospectively analysed 35 patients with drug-resistant tuberculous spondylitis. After surgery, individualised chemotherapy was tailored for each patient according to the drug-resistance profile and previous history of chemotherapy. The patients were followed up clinically and radiologically for an average period of 35.8xa0months.ResultsAmong 35 drug-resistant spinal tuberculosis cases, 13 were retreatment cases. Twelve were multi-drug resistant tuberculosis (MDR-TB), and 23 were non-MDR-TB. The patients with MDR-TB and non-MDR-TB had undergone previous chemotherapy for an average of 14.50u2009±u20092.00 (0–60) months and 4.56u2009±u20091.54 (0–74) months, respectively. A total of 32 cases underwent open operations, and the other three had percutaneous drainage and local chemotherapy. Patients received individualised chemotherapy for an average of 23.6xa0months postoperatively. Local recurrence was observed in six patients. Thirty-three patients had been cured at the final follow-up, and the other two were still receiving chemotherapy.ConclusionsDrug-resistant tuberculous spondylitis is mainly acquired through previous irregular chemotherapy and the spreading of drug-resistant strains. Management with a combination of surgery and individualised chemotherapy is feasible in the treatment of severe complications and the prevention of acquired drug resistance.

Repair of large segmental bone defects using bone marrow stromal cells with demineralized bone matrix

Objective:u2002 The aim of the present study was to evaluate the effect of tissue‐engineered constructs on repair of large segmental bone defects in goats.

Biomechanical comparison of anterior lumbar screw-plate fixation versus posterior lumbar pedicle screw fixation

SummaryAnterior lumbar interbody fusion (ALIF) followed by posterior pedicle screw fixation (PSF) in a second procedure is mostly used to implement lumbar spine fusion. ALIF followed by anterior lumbar screw-plate has a lot of advantages, but its biomechanical stability requires confirmation. This study evaluated the biomechanical stability of a novel anterior lumbar locked screw-plate (ALLSP) by comparison with posterior lumbar PSF. Twelve fresh human cadaveric lumbar specimens (L4–L5) were assigned to four groups: ALIF+PSF group, ALIF+ALLSP (both fixed) group, ALIF group and an untreated control (both non-fixed) group. The first three groups received implantation of a rectangular titanium cage. Tests under axial compression, flexion, extension, lateral bending, or rotation showed that the fixed groups had significantly stronger stability than the non-fixed groups (P=0.000 for all). The ALIF+ALLSP group had significantly greater axial stiffness under applied axial compression and significantly less angular displacement under rotational forces than the ALIF+PSF group. The angular displacement of the ALIF+ALLSP group was less under flexion than that of the ALIF+PSF, and the angular displacement under lateral bending and extension was greater, but these differences were not statistically significant. In summary, the ALLSP conforms to the anterior lumbar spine and has good biomechanical stability. It is a reliable choice for enhancing the stability of ALIF.Anterior lumbar interbody fusion (ALIF) followed by posterior pedicle screw fixation (PSF) in a second procedure is mostly used to implement lumbar spine fusion. ALIF followed by anterior lumbar screw-plate has a lot of advantages, but its biomechanical stability requires confirmation. This study evaluated the biomechanical stability of a novel anterior lumbar locked screw-plate (ALLSP) by comparison with posterior lumbar PSF. Twelve fresh human cadaveric lumbar specimens (L4–L5) were assigned to four groups: ALIF+PSF group, ALIF+ALLSP (both fixed) group, ALIF group and an untreated control (both non-fixed) group. The first three groups received implantation of a rectangular titanium cage. Tests under axial compression, flexion, extension, lateral bending, or rotation showed that the fixed groups had significantly stronger stability than the non-fixed groups (P=0.000 for all). The ALIF+ALLSP group had significantly greater axial stiffness under applied axial compression and significantly less angular displacement under rotational forces than the ALIF+PSF group. The angular displacement of the ALIF+ALLSP group was less under flexion than that of the ALIF+PSF, and the angular displacement under lateral bending and extension was greater, but these differences were not statistically significant. In summary, the ALLSP conforms to the anterior lumbar spine and has good biomechanical stability. It is a reliable choice for enhancing the stability of ALIF.

Imaging Anatomical Research on the Operative Windows of Oblique Lumbar Interbody Fusion

To provide applied anatomical evidence of the preoperative assessment of oblique lumbar interbody fusion (OLIF), the anatomical parameters of the OLIF operative window were observed through computed tomography angiography (CTA). We selected imaging data from 60 adults (30 males, 30 females) who underwent abdominal CTA and T12-S1 vertebral computed tomography (CT) with three-dimensional reconstruction. The OLIF operative windows at the L1-2, L2-3, L3-4, L4-5 and L5-S1 levels were as follows: the vascular window, bare window, psoas major window, ideal operative window, and actual operative window. Each levels actual operative window was statistically analyzed based on an actual operative window of <1 cm and ≥1 cm. The vascular window was largest at L4-5 (1.72 ± 0.58 cm). The bare window was largest at L5-S1 (1.59 ± 0.93 cm) and smallest at L3-4 (1.37 ± 0.51 cm). The psoas major window was largest at L3-4 (1.14 ± 0.35 cm) and smallest at L1-2 (0.41 ± 0.34 cm). The ideal operative window was largest at L4-5 (3.74 ± 0.36 cm) and smallest at L1-2 (3.23 ± 0.30 cm). The actual operative window was largest at L3-4, followed by L2-3, L4-5, L1-2, and L5-S1, which were 2.51 ± 0.56 cm, 2.28 ± 0.54 cm, 2.01 ± 0.74 cm, 1.80 ± 0.45 cm and 1.59 ± 0.93 cm, respectively (P = 0.000), and the percentages of the actual surgical window were 69%, 66%, 53%, 56% and 43%, respectively. The actual surgical window was <1 cm in 2 cases at L1-2 (3.3%), 4 cases at L4-5 (6.7%), and 17 cases at L5-S1 (28.3%) (11 males and 6 females). The regional anatomy of each level related to OLIF has its own peculiarities, and not all levels are suitable for OLIF. Before OLIF surgery, surgeons should analyze the imaging anatomy and select the appropriate surgical procedures.

Large blood vessel stretch in lumbar spine through anterior surgical approach: An experimental study in adult goat

Background: Various anterior lumbar surgical approaches, including the minimally invasive approach, have greatly improved in recent years. Vascular complications resulting from ALIF are frequently reported. Little information is available about the safety of large blood vessel stretch. We evaluated the right side stretch limit (RSSL) of the abdominal aorta (AAA) and the inferior vena cava (IVC) without blood flow occlusion and investigated stretch-induced histological injury and thrombosis in the iliac and femoral arteries and veins and the stretched vessels. Materials and Methods: The RSSL of blood vessels in five adult goats was measured by counting the number of 0.5-cm-thick wood slabs that were inserted between the right lumbar edge and the stretch hook. Twenty seven adult goats were divided into three groups to investigate histological injury and thrombosis under a stretch to 0.5 cm (group I) 1.5 cm (group II) for 2 h, or no stretch (group III). Blood vessel samples from groups I and II were analyzed on postsurgical days 1, 3, and 7. Thrombogenesis was examined in the iliac and femoral arteries and veins. Results: The RSSL of large blood vessels in front of L4/5 was 1.5 cm from the right lumbar edge. All goats survived surgery without complications. No injury or thrombosis in the large blood vessels in front of the lumbar vertebrae and in the iliac or femoral arteries and veins was observed. Under light microscopy, group I showed slight swelling of endothelial cells in the AAA and no histological injury of the IVC. The AAA of group II showed endothelial cell damage, unclear organelles, and incomplete cell connections by electron microscopy. Conclusions: The AAA and IVC in a goat model can be stretched by ≤0.5 cm, with no thrombosis in the AAA, IVC, iliac or femoral arteries and veins.