[Effects on single segmental lumbar stability after graded facetectomy and laminectomy: a finite element study].

OBJECTIVE: To explore the effects on degenerative single segmental lumbar spinal stability after posterior graded laminectomy and facetectomy by a finite element method. METHODS: A finite element model of L3-S1 segments with a single segmental degeneration at L4-5 level was established. Different models of L4-L5 segmental instability after posterior graded laminectomy and facetectomy were established. And interior 1/3, 1/2, 2/3 of laminar and bilateral facet joints were resected. Physical loads were applied to the models and the changes of range of motion (ROM) at L4-5 level in different models were recorded during flexion, extension, lateral bending and rotation. RESULTS: As compared to preoperative model, after resecting 1/3 bilateral facet joints at L4-5 level, L4-5 segmental ROM increased 18% during flexion, 27% during extension and 45% during torsion. And the increased degree of ROM became more obvious along with a greater resection range of bilateral facet joints. No significant difference existed in L4-5 segmental ROM during lateral bending in all models. CONCLUSION: Facet joints play vital roles in lumbar segmental stability. And segmental instability may occur when 1/3 bilateral facet joints are resected.

Ginkgolide B Protects Against Ischemic Stroke Via Modulating Microglia Polarization in Mice.

AIM: Ginkgolide B (GB) has shown neuroprotective effect in treating ischemic stroke, related to its property of anti-inflammation. Nevertheless, it is unclear whether GB is able to modulate microglia/macrophage polarization, which has recently been proven to be vital in the pathology of ischemic stroke. METHODS: We performed transient middle cerebral artery occlusion (tMCAO) on C57BL/6J male mice and induced cultured BV2 microglia and primary bone marrow-derived macrophages to be M1/2 phenotype by LPS+ interferon-γ and IL-4, respectively. Immunofluorescence and flow cytometry were used for detecting the specialized protein expression of M1/2, such as CD206 and CD16/32. qPCR was utilized to detect the signature gene change of M1/2. RESULTS: GB significantly reduced cerebral ischemic damage and ameliorated the neurological deficits of mice after tMCAO. More importantly, our experiments proved that GB promoted microglia/macrophage transferring from inflammatory M1 phenotype to a protective, anti-inflammatory M2 phenotype in vivo or vitro. CV3988 and silencing the platelet activator factor (PAF) receptor by siRNA demonstrated that PAF receptor was involved in the modulation of microglia/macrophage polarization. CONCLUSION: Our results reveal a novel pharmacological effect of GB in modulating microglia/macrophage polarization after tMCAO, thus deepening our understanding of neuroprotective mechanisms of GB in treatment of ischemic stroke. Furthermore, this new mechanism may allow GB to be used in many other microglia/macrophage polarization-related inflammatory diseases.

[Present application situation of medical consumble materials and the standard management].

This paper introduces the present application situation of medical consumable materials in consumption, use, quality control and computer management. It presents the concrete contents of standard management in quality guarantee, rules and regulations, and cost reduction.