Free-hand technique of C7 pedicle screw insertion using a simply defined entry point without fluoroscopic guidance for cervical spondylotic myelopathy patients with C3 to C6 instrumented by lateral mass screws: a retrospective cohort study.

BACKGROUND: Nowadays, both lateral mass screw (LMS) and pedicle screw were effective instrumentation for posterior stabilization of cervical spine. This study aims to evaluate the feasibility of a new free-hand technique of C7 pedicle screw insertion without fluoroscopic guidance for cervical spondylotic myelopathy (CSM) patients with C3 to C6 instrumented by lateral mass screws. METHODS: A total of 53 CSM patients underwent lateral mass screws instrumentation at C3 to C6 levels and pedicle screw instrumentation at C7 level were included. The preoperative 3-dimenional computed tomography (CT) reconstruction images of cervical spine were used to determine 2 different C7 pedicle screw trajectories. Trajectory A passed through the axis of the C7 pedicle while trajectory B selected the midpoint of the base of C7 superior facet as the entry point. All these 53 patients had the C7 pedicle screw inserted through trajectory B by free-hand without fluoroscopic guidance and the postoperative CT images were obtained to evaluate the accuracy of C7 pedicle screw insertion. RESULTS: Trajectory B had smaller transverse angle, smaller screw length, and smaller screw width but both similar sagittal angle and similar pedicle height when compared with trajectory A. A total of 106 pedicle screws were inserted at C7 through trajectory B and only 8 screws were displaced with the accuracy of screw placement as high as 92.5%. CONCLUSION: In CSM patients with C3 to C6 instrumented by LMS, using trajectory B for C7 pedicle screw insertion is easy to both identify the entry point and facilitate the rod insertion.

Inhibition of microRNA-129-5p expression ameliorates ultraviolet ray-induced corneal epithelial cell injury via upregulation of EGFR.

Existing evidence has highlighted the effect of ultraviolet light radiation leading to corneal epithelium impairment. During this study, we aim to investigate the effect of microRNA-129-5p (miR-129-5p) on the wound healing process of corneal epithelial cells (CECs) induced by ultraviolet rays in mice by targeting epidermal growth factor receptor (EGFR). First, mouse models of ultraviolet ray-induced CEC injury were established and intrastromally injected with different mimic, inhibitor, and short interfering RNA (siRNA) to detect the effect of miR-129-5p on CEC injury. Subsequently, the corneal tissues were obtained to detect the antioxidant ability and EGFR-positive expression rate. The dual-luciferase reporter gene assay was used to test whether EGFR could directly target miR-129-5p. To further investigate the specific mechanism of miR-129-5p and EGFR in CEC injury, CECs were cultured and transfected with miR-129-5p mimic, miR-129-5p inhibitor, siRNA-EGFR, and miR-129-5p inhibitor + siRNA-EGFR. miR-129-5p has been proven to directly target EGFR. Inhibition of miR-129-5p is able to increase the antioxidant capacity, EGFR-positive rate and the expressions of EGFR, B-cell lymphoma-2, zonula occluden-1, occludin, and keratinocyte growth factor-2, but decrease the expression of vascular endothelial growth factor, BCL2-associated X protein, interleukin (IL)-1ß, and IL-4. Inhibition of miR-129-5p arrests cells at the S and G2 phases and decreases apoptosis. Our study provides evidence stating that inhibiting miR-129-5p and upregulating EGFR could aid in the repair of mice CEC injury induced by ultraviolet radiation. Therefore, inhibition of miR-129-5p might provide a basic theory in the repair of CEC injury caused by ultraviolet rays.

[Effect of Rhizoma Curcumae and arsenite trioxide on proliferation and signal transduction molecule of lens epithelial cell].

OBJECTIVE: To investigate the effect of Rhizoma Curcumae (RC), arsenite trioxide (As2O3) on proliferation ana signal transduction molecule in lens epithelial cell (LEC), in order to provide experiment evidence for prevention and treatment of after cataract. METHOD: Proliferation of cultured bovine LEC were induced by induced by recombinant human basic fibroblast growth factor (rhbFGF); Inhibitory rates of LEC proliferation induced by RC, As2O3 were detected by methyl thiazolyl tetrazolium (MTT); Inhibitory effects of expression of proliferating cell nuclear antigen (PCNA) induced by RC, As2O3 in LEC were assayed via flow cytometer (FCM); Concentrations of LEC calcium ([Ca2+]i) were determined by spectrofluoremeter, intracellular concentrations of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) of LEC were measured by radioimmunoassay. RESULT: Inhibitory rates of RC, As2O3 on LEC proliferation induced by rhbFGF increased significantly, showing dose-dependent (P < 0.01). PCNA expression of LEC proliferation induced by rhbFGF were down regulated obviously by RC, As2O3, showing dose-dependent (P < 0.01). Concentrations of [Ca2+]and cAMP increased and cGMP decreased significantly in LEC of proliferation inhibited by RC, As2O3 (P < 0.01). CONCLUSION: RC, As2O3 can inhibit LEC proliferation obviously. Signal transductions of [Ca2+]i, cAMP, cGMP may be the important molecular mechanism. There are broad prospect for RC, As2O3 on prevention and treatment of after cataract.

[Signal transduction mechanism of curcumin in inhibiting the proliferation of bovine lens epithelial cell induced by recombinant human epidermal growth factor].

OBJECTIVE: To investigate the signal transduction mechanism of curcumin in inhibiting the proliferation of bovine lens epithelial cell (LEC) induced by recombinant human epidermal growth factor (rhEGF). METHODS: There were three groups in this experiment, which were normal control group, untreated group and curcumin-treated group. Proliferation of LEC was induced by rhEGF (50 microg/L). The concentration of intracellular Ca(2+) ([Ca(2+)](i)) in LEC was measured with Fura-2/AM by spectrofluorimetry. The contents of intracellular cAMP and cGMP were assayed by radioimmunoassay. RESULTS: The [Ca(2+)]i in LEC was obviously increased in the untrated group as compared with that in the normal control group (P<0.01), and the [Ca(2+)](i) in LEC in the curcumin-treated group was highest among three groups (P<0.01). The content of intracellular cAMP in LEC was decreased while the content of intracellular cGMP was obviously increased in the untreated group as compared with those in the normal control group (P<0.01). The content of intracellular cAMP in LEC was higher in the curcumin-treated group than that in the untreated group, while the content of intracellular cGMP was lower than that in the untreated group (P<0.01). CONCLUSION: The antiproliferation effects of curcumin on LEC may relate to the regulations of multiple processes of signal transduction.