BACKGROUND: At present, more and more people pay attention to the protection of sub-hypothermia on cerebral ischemic tissue and the effect of sub-hypothermia treatment on inflammatory reaction after cerebral ischemia-reperfusion.OBJECTIVE: To investigate the effect of sub-hypothermia on inflammatory cytokine in cerebral ischemic area of rats and protection on cerebral reperfusion injury.DESIGN: Randomized controlled study on the basis of animals.SETTLNG: People's Hospital of Hubei Province.MATERIALS: The experiment was completed at Laboratory Center of Renmin Hospital of Wuhan University from October 2004 to February 2005. Totally 50 healthy SD rats of clean grade were selected in this study.METHODS: Ten SD rats were divided randomly into normal group and sham operation group with 5 in each group. Other 40 rats were divided randomly into normal temperature cerebral ischemia group and sub-hypothermia cerebral ischemia group with 20 in each group. Rats except 5 in normal group were used to establish reversible ligation model of left middle cerebral artery (MCA) with Longa ligation method. Rats in sham operation group and normal temperature group were put in 20 ℃ room, and anus temperature was maintained at 37 ℃; rats in sub-hypothermia group were put in 4 ℃ room and anus temperature was maintained at (33.0±1.0) ℃.Rats in sub-hypothermia group were treated with sub-hypothermia on whole body, after ischemia, temperature was changed normally, and reperfusion was started 3 hours after cerebral ischemia. All modeling rats were scored with neurological defect: 0 point: none of neurological defect; 1 point: unable to unfold bilateral anterior claws; 2 points: cycling to hemiplegia side during walking; 3 points: falling to hemiplegia side; 4 points: unable to self-walk and with unconsciousness.MAIN OUTCOME MEASURES: Expression of tumor necrosis factor (TNF) andinterleukin-1 in cerebral tissue of ischemic rats, percentage of volume of cerebral infarction,and neurological functional scores.RESULTS: Fifteen rats were excluded because of intracranial hemorrhage,anesthetic accident and unqualified neurological functional scores. Other 15 rats with successful modeling were supplied randomly, and totally 50rats entered the final analysis. ① Number of TNF positive cell in immunohistochemical staining: There were no significant differences between normal group and sham operation group [(3.54±1.24, 3.71±1.50) /sight]; but numbers in sub-hypothermia group were lower than those in normal temperature group [(31.94±7.23, 69.20±9.43)/sight, F=179.16, P ＜ 0.001]. ②Numbers of interleukin-1 positive cells in immunohistochemical staining:There were not significant differences between normal group and sham operation group [(3.20±1.34, 3.89±2.08) /sight]; but numbers in sub-hypothermia group were lower than those in normal temperature group [(28.95±4.97, 55.79±7.93)/sight, F=174.95, P ＜ 0.001]. ③ Volume percentage of infarct focus: Percentage in sub-hypothermia group was lower than that in normal temperature group [(21.06±2.42)%, 30.32±2.71], F =374.87, P ＜ 0.001]. ④ Neurological functional scores: Percentage in subhypothermia group was lower than that in normal temperature group [(1.35±0.27)%, (2.04±0.34)%, F=117.17, P ＜ 0.001].CONCLUSION: ① Volume of cerebral infarction focus is lower in subhypothermia group than that in normal temperature group, this suggests that sub-hypothermia can protect ischemic neurons. ② Positive expressions of TNF and interleukin-1 are observed rarely in normal group and sham operation group, but more expression of positive cells are observed in cerebral ischemic area with 24-hour reperfusion after ischemia, this suggests that cerebral ischemia starts expression of inflammatory cytokine, evoke inflammatory cascade reaction, deteriorate cerebral ischemia-reperfusion injury. Therefore, inhibition of inflammatory cascade reaction is one of important mechanisms of protecting brain.

In the present study, a finite element model of L4-5 lumbar motion segment was established based on the CT images and a combination with image processing software, and the analysis of lumbar biomechanical characteristics was conducted on the proposed model according to different cases of flexion, extension, lateral bending and axial rotation. Firstly, the CT images of lumbar segment L4 to L5 from a healthy volunteer were selected for a three dimensional model establishment which was consisted of cortical bone, cancellous bone, posterior structure, annulus, nucleus pulposus, cartilage endplate, ligament and facet joint. The biomechanical analysis was then conducted according to different cases of flexion, extension, lateral bending and axial rotation. The results showed that the established finite element model of L4-5 lumbar segment was realistic and effective. The axial displacement of the proposed model was 0.23, 0.47, 0.76 and 1.02 mm, respectively under the pressure of 500, 1 000, 1 500 and 2 000 N, which was similar to the previous studies in vitro experiments and finite element analysis of other people under the same condition. The stress distribution of the lumbar spine and intervertebral disc accorded with the biomechanical properties of the lumbar spine under various conditions. The established finite element model has been proved to be effective in simulating the biomechanical properties of lumbar spine, and therefore laid a good foundation for the research of the implants of biomechanical properties of lumbar spine.
Biomechanical Phenomena ; Finite Element Analysis ; Humans ; Intervertebral Disc ; anatomy & histology ; Lumbar Vertebrae ; anatomy & histology ; Models, Anatomic ; Pressure ; Prostheses and Implants ; Range of Motion, Articular ; Rotation

Based on the surgical model using transforaminal lumbar interbody fusion (TLIF) to treat lumbar spondylolisthesis, this paper presents the investigations of the biomechanical characteristics of cage and pedicle screw in lumbar spinal fusion implant fixed system under different combinations with finite element method. Firstly, combining the CT images with finite element pretreatment software, we established three dimensional nonlinear finite element model of human lumbar L4-L5 segmental slight slippage and implant under different fixed combinations. We then made a comparison analysis between the biomechanical characteristics of lumbar motion range, stress distribution of cage and pedicle screw under six status of each model which were flexion, extension, left lateral bending, right lateral bending, left axial rotation and right axial rotation. The results showed that the motion ranges of this model under different operations were reduced above 84% compared with those of the intact model, and the stability of the former was improved significantly. The stress values of cage and pedicle screw were relatively larger when they were fixed by single fusion device additional unilateral pedicle screw, but there was no statistically significant difference. The above research results would provide reference and confirmation for further biomechanics research of TLIF extracorporal specimens, and finally provide biomechanical basis for the feasibility of unilateral internal fixed diagonal intervertebral fusion TLIF surgery.
Biomechanical Phenomena ; Finite Element Analysis ; Humans ; Lumbar Vertebrae ; Models, Anatomic ; Motion ; Pedicle Screws ; Posture ; Range of Motion, Articular ; Rotation ; Spinal Fusion

Objective To establish an index system of science and technology evaluation for public hospitals in Shanghai, which is scientific and rational, operable, promotable, and comparable.The purpose is to improve the comprehensive hospital evaluation system and promote the science and medical technology innovation development in Shanghai.Methods Based on overseas and domestic research experiences and Shanghai′s specifics, literature analysis and Delphi specialist consultation method were used for rationalization proposals for building such a system.Results This index system comprises three level-1 indicators of basis and conditions, results and outputs and social benefits and impacts, eight level-2 indicators and 24 level-3 indicators.Conclusions This index system should be improved stage by stage.Classification by type and level of public hospitals should be used in such evaluation, while horizontal development level and vertical development speed of science and technology should be combined.A unified evaluation standard should be developed by professional organizations.

OBJECTIVE: To study the proteins related to paclitaxel-resistant of ovarian cancer cell line. METHODS: The total proteins of paclitaxel-resistant and paclitaxel-sensitive human ovarian cancer cell lines were separated by 2-dimensional gel electrophoresis (2-DE). The differentially expressed proteins were analyzed using image analysis software. The differential proteins were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Western blot was used to determine the differential expression levels of the 2 proteins. RESULTS: Forty differentially expressed proteins were found by image analysis software, and 24 differential proteins were identified by mass spectrometry. These proteins included proliferation cell nuclear antigen (PCNA), nm23, prohibitin (PHB), annexin, alpha-enolase, heat shock protein (HSP), and so on. CONCLUSION Twenty-four proteins in human ovarian cancer cell lines of paclitaxel-resistant and paclitaxel-sensitive are found by proteomic techniques, which may be involved in the paclitaxel-resistance of human ovarian cancer cells.
Antineoplastic Agents, Phytogenic ; pharmacology ; Cell Line, Tumor ; Drug Resistance, Neoplasm ; genetics ; Electrophoresis, Gel, Two-Dimensional ; Female ; Humans ; NM23 Nucleoside Diphosphate Kinases ; analysis ; Ovarian Neoplasms ; genetics ; metabolism ; pathology ; Paclitaxel ; pharmacology ; Proliferating Cell Nuclear Antigen ; analysis ; Proteome ; analysis ; Proteomics ; methods ; Repressor Proteins ; analysis