AIM: To investigate the molecular mechanism of microRNA-21 (miR-21) in the regulation of Schwann cell proliferation following nerve injury.METHODS:The expression of miR-2l was detected by real-time PCR. Synthetic miR-21 mimic and its control were transfected into rat Schwann cells.CCK-8 assay was performed to evaluate the influence of miR-21 on the proliferation of Schwann cells.The cell cycle distribution was determined by flow cytometry. The expression of transforming growth factorβ-induced protein ( TGFBI) and cyclin D1 were detected by Western blotting. RESULTS:The expression of miR-21 in model group was 7.87 ±0.75 and 7.75 ±0.80 times higher than that in sham operation group and blank group respectively.After transfected with miR-21 mimic, the expression of miR-21 in experimen-tal group was 2.21 ±0.14 and 2.29 ±0.21 times higher than that in negative control group and blank group respectively. Moreover, the A450 value of CCK-8 assay in experimental group at 48 h was higher than that in negative control group and blank group.The proliferation index in experimental group was higher than that in negative control group and blank group. At the same time, the expression of TGFBI obviously decreased and the cyclin D1 increased in the Schwann cells 48 h after transfection with miR-21.CONCLUSION:miR-21 promotes the proliferation activity of Schwann cells by down-regulating TGFBI expression.

OBJECTIVETo explore a new method for body surface orientation of the puncture site, determination of the direction of the needling and puncture depth for caudal block.

METHODSThree-dimensional reconstruction of the pelvis was performed in 8 cases for measuring the distances between the sacral hiatus and the planned site of anesthetic delivery and the size of the sacral hiatus. After image processing with the technique of shaded surface display (SSD), the shapes of sacral hiatus and sacral tube were evaluated.

RESULTSThree-dimensional reconstruction of the pelvis in the 8 cases allowed clear view from any directions of the sacral hiatus and sacral tube and accurate measurement of the size of the sacral hiatus. After simulated cutting of half of the rumpbone, the distances between the sacral hiatus and the drug injection site were accurately measured. With these measurements, accurate preoperative localization of the puncture site on the skin was achieved and the anesthesia was successful in all the cases.

CONCLUSIONSThis technique can provide accurate data for localization of the puncture site on the skin and determination of the direction of the needling and the puncture depth for caudal block to increase the successful rate of anesthesia, lower the operative risks and allow simulated operative training.

Adolescent ; Adult ; Aged ; Anesthesia, Caudal ; methods ; Anthropometry ; methods ; Female ; Humans ; Imaging, Three-Dimensional ; Male ; Middle Aged ; Reproducibility of Results ; Sacrum ; diagnostic imaging ; Tomography, Spiral Computed ; methods