OBJECTIVETo investigate the effects of exogenous hydrogen sulfide (H2S) on β-site APP cleaving enzyme 1 (BACE-1) and β-amyloid peptide (Aβ) metabolism in primary culture of neurons under high-glucose condition.

METHODSThe cortical neurons in primary culture under normal and high glucose (60 mmol/L) conditions for 24 h were exposed to 25, 50 and 100 µmol/L NaHS. Aβ1-42 concentration in the cell culture was measured by ELISA, and BACE-1 mRNA and protein levels were detected by fluorescent quantitative real-time PCR and Western blotting, respectively.

RESULTSCompared with the neurons cultured in normal glucose, the neurons exposed to high glucose showed significantly increased Aβ1-42 concentration and BACE-1 mRNA and protein expressions (P<0.05). Exposure to 25, 50 and 100 µmol/L NaHS significantly decreased Aβ1-42 concentration and BACE-1 mRNA and protein expressions in the high-glucose cell culture (P<0.05).

CONCLUSIONNeurons exposed to high glucose exhibit increased Aβ1-42 levels and BACE-1 mRNA and protein expressions, which can be concentration-dependently decreased by NaHS.

Amyloid Precursor Protein Secretases ; metabolism ; Amyloid beta-Peptides ; metabolism ; Animals ; Aspartic Acid Endopeptidases ; metabolism ; Cells, Cultured ; Culture Media ; chemistry ; Glucose ; chemistry ; Hydrogen Sulfide ; pharmacology ; Neurons ; drug effects ; metabolism ; Peptide Fragments ; metabolism ; Rats ; Rats, Sprague-Dawley

Objective To retrospectively evaluate and analyze the clinical effect of posterior pedicle subtraction osteotomy in treating chronic, posttraumatic thoracolumbar kyphosis. Methods Nineteen patients (11 males and 8 females) with chronic, posttraumatic thoracolumbar kyphosis were corrected surgically. The patients were at age range of 29-61 years (mean 42 years). Preoperative kyphosis Cobb angle ranged from 31° to 63° (mean 47°) and trauma history ranged from 8 months to 63 months (mean 29 months). All patients were treated with pedicle subtraction osteotomy according to the size of Cobb angle, extent of spinal stenosis and source of compression. Results Sagittal alignment was improved to average 40.2°, with a correction rate of 85.8%. Two patients developed postoperative leakage of cerebrospinal fluid. Among them, one was combined with encephalic infection and cured with active treatment, and the other developed postoperative wound infection, which were treated conservatively with antibiotics and local wound care. There were no other severe complications. The average follow-up period was 15 months (range 6-41 months). At the last follow-up, clinical symptoms and neurological function were improved significantly. Neither loss of correction nor failure of internal fixators was observed. X-ray and dynamic X-ray films showed a 100% fusion in all patients. Conclusions The single-stage posterior pedicle subtraction osteotomy is a safe and effective procedure for correction of posttraumatic thoracolumbar kyphosis. It is possible and safe to obtain a correction within 55° on single segment by this technique.