Objective To establish human hepatic carcinoma HepG2 cell line in which the expression of exogenous gene could be controlled by doxycycline. Methods The expression plasmid pTet-on was transfected into hepG2 cells by lipofectamine 2000.The stably transfected positive clones were screened with G 418 and subcultured. The expression level of luciferase induced by doxycycline at a concentration of 1 ?g/ml in stably transfected cells was detected one by one by transient transfection of plasmid pTRE-luc into the stably transfected cells. Results The basal expression activity of luciferase in cells of clone No 6 was 87, and the activity was 16764 after induction with doxycycline. Conclusion The HepG2/Tet-on cell line was a regulatory human hepatoma cell line, which is useful for the study of carcinogenesis and gene therapy of hepatic carcinoma.

ObjectiveTo investigate the effect of dexmedetomidine on the median effectivetarget effectsite concentration (EC50) of remifentanil required for preventing body movement in response to skin incision made under propofol sedation.MethodsForty ASA Ⅰ or Ⅱ patients aged 20-50 yr weighing 45-58 kg scheduled for elective breast tumor excision were randomly allocated into 2 groups ( n =20 each):group remifentanil (group R) and group remifentanil + demedetomidine ( group RD).Sedation was induced with propofol TCI at target plasma concentration of 3.0 mg/L in both groups.In group RD dexmedetomidine 1.0 μg/kg was infused iv over 10 min before start of propofol TCI,while in group R equal volume of normal saline was infused instead of dexmedetomidine.Remifentanil TCI was started with target effect-site concentration set at 3.0 and 2.5 μg/L in groups R and RD respective at 13 min after beginning of propofol TCI.Skin incision (3 cm in length) was made when the target concentrations of propofol and remifentanil TCI were reached.Body movement was assessed by a nurse not involved in this study.EC50 and 95％ confidence interval (CI) of remifentanil were determined by up-and-down technique.The target effect-site concentration was increased or decreased by 20％ depending on the response of the previous patient to skin-incision.ResultsThe EC50 of remifentanil for preventing body movement in response to skin incision performed under propofol sedation was 1.7 μg/L (95％ CI 1.5-1.9 μg/L) and 2.5 μg/L (95％ CI 2.2-2.7μg/L) in groups RD and R respectively.The EC50 of remifentanil was significantly lower in group RD than in group R.ConclusionDexmedetomidine 1.0 μg/kg can decrease EC50 of remifentanil for preventing body movement in response to skin incision made under propofol sedation.

Objective To investigate the effect of dexmedetomidine on bispectral index (BIS) value at loss of consciousness (LOC) caused by propofol given by target-controlled infusion (TCI).Methods One hundred and twenty ASA Ⅰ or Ⅱ patients,aged 20-50 yr,weighing 41-68 kg,scheduled for general surgery were randomly divided into 3 groups (n =40 each):propofol group (group P),dexmedetomidine 0.5 μg/kg + propofol group (group D1P) and dexmedetomidine 1.0 μg/kg + propofol group (group D2P).The patients in each group were randomly assigned into 5 subgroups ( n =8 each):groups P0-4 receiving TCI of propofol with the target effect-site concentration (Ce) set at0,1,2,3 and 4 mg/L respectively.Groups D1P0-4 received iv infusion of dexmedetomidine 0.5 μg/kg at a rate of0.05μg·kg-1 ·min-1 and TCI of propofol with the target Ce set at 0,1,2,3 and 4 mg/L respectively at 5 min after the end of dexmedetomidine infusion.Groups D2 P0-4 received iv infusion of dexmedetomidine 1.0 μg/kg at a rate of 0.1μg· kg- 1· min- 1 and TCI of propofol with the target Ce set at 0,1,2,3 and 4 mg/L respectively at 5 min after the end of dexmedetomidine infusion.Three minutes after TCI of propofol was started,OAA/S score and BIS value were recorded.The OAMS score ≤ 2 was defined as LOC.The EC50 and 95％ confidence interval of propofol for LOC and BIS50 and 95％ confidence interval at LOC were calculated by Probit analysis.Prediction probability (Pk) of BIS value at LOC was calculated using Smith method.Results Compared with group P,EC50 was significantly decreased,BIS50 was significantly increased ( P ＜ 0.05 or 0.01 ),and no significant change was found in Pk in groups D2 P and D1 P ( P ＞ 0.05).There were no significant differences in EC50,BIS50 and Pk between groups D2 P and D1P ( P ＞ 0.05).Conclusion BIS value can accurately predict the level of consciousness during anesthesia with dexmedetomidine and TCI of propofol,but BIS value is increased at LOC.

BACKGROUND: Biological fixation refers to the treatment of coarse or porous prosthetic surface. It is favorable to "bone ingrowth" prosthesis to achieve long-term stability. Porous tantalum is the latest scientific product that appears suitable to prosthetic surface owing to its porous feature and has been attracting a great deal attention.OBJECTIVE: To investigate the therapeutic efficacy of a porous tantalum uncemented acetabular cup in acetabular revision arthroplasty.DESIGN, TIME AND SETTING: A retrospective case analysis was performed at the Department of Orthopedics, Changhai Hospital, Second Military Medical University of Chinese PLA between April and November 2006.PARTICIPANTS/MATERIALS: Sixteen patients (16 hips), 7 males and 9 females, aged 54-81 years old, who received treatment at the Department of Orthopedics, Changhai Hospital, Second Military Medical University of Chinese PLA were included in this study. Of these patients, 2 suffered from femoral neck fracture, 6 from aseptic femoral head necrosis, and 8 from osteoarthritis. Trabecular metal cup (Zimmer, Warsaw, Indiana) provided a titanium alloy bottom layer and porous tantalum-coated surface, which was realized by technical combination of bone trabecular tantalum and titanium alloy. The prosthesis contained an ultrahigh modulus polyethylene lining.METHODS: All patients underwent acetabular revision with modular porous tantalum uncemented acetabular cup. Prior to replacement, acetabular defects and femoral prosthesis were evaluated. A posterolateral approach of hip joint was made. Following acatabular prosthesis removal, bone cement was cleared with osteotome, simultaneously scar tissue, granulation tissue, and fibrous limiting membrane in the acetabular fossa were erased with curette to avoid further damage to sclerotin. Bacteriological examination and susceptibility test with respect to intraarticular tissue fluid confirmed aseptic loosening. Antibiotics were used in each patient to prevent infection. Antibiotics and low molecular heparin were used afterwards to prevent infection and thromboembolism, respectively. Patients could not load within 4 weeks but could walk with the aid of two canes within subsequent 6 weeks. One week after surgery, plain X-ray films were taken in the lateral plane.MAIN OUTCOME MEASURES: Prior to and 6, 12, and 24 months after surgery, Harris hip score and University of California Los Angeles (UCLA) activity score were assessed. The position of acetabular prosthesis was observed through an anteropostedor pelvic radiograph.RESULTS: The average follow-up time was 24 months (range 18-25 months). Harris hip score significantly increased from 32.6 points (range 21-54 points) prior to revision to 87.5 points (range 56-90 points) after revision (P < 0.05). UCLA activity score significantly increased from 3.8 points (2-5 points) prior to revision to 8.2 points (range 6-9 points) after revision (P<0.05). The anteropostedor pelvic radiographs taken in the last follow-up displayed no phenomena regarding non-stability including prosthesis aversion and subsidence and revealed that the in-growth of sclerotin surrounding the bone trabecular tantalum acetabular cup. Postoperative complications were found in none of 16 patients. By the last follow-up, there had been 14 cases who did not complain of pains while walking and 2 cases that had slight pain and slight limp while walking. Deep venous thrombosis or nerve injury did not appear afterwards. No cases needed another acetabular revision arthroplasty.CONCLUSION: For cases of failed primary fixation of artificial acetabular cup, application of porous tantalum uncemented acetabular cup can produces favorable results in acetabular revision if no bone defects exist.

Objective To investigate the mechanism by which HBx facilitates the proliferation of hepatoma cells. Methods The expression of plasmid pHA-HBx encoding full length of HBx was transfected into HepG2 cell lines and the transformed cells were identified by RT-PCR. The nude mouse model of transplanted human hepatoma HBx-transfected HepG2 cells was established. The expression of VEGF both in HepG2 cell-formed tumors and HBx-transfected cell-formed tumors in nude mice was examined immunohistochemically. Results RT-PCR showed that HBx gene was integrated into the genome DNA of HepG2 cells and amplified; The rate of tumor formation in nude mice both of HepG2 cells and HBxtransfected HepG2 cells was 100%; The growth speed of HBx-transfected tumors was much faster than that in control group; The average volume of HBx-transfected tumors and non-transfected tumors was 2. 86?0. 34 cm3 and 2.48?0.22 cm3 respectively after 8 weeks(t=1.905 ,P

Objective To investigate the effects of HBx on proliferation and apoptosis of human hepatocellular carcinoma cell line HepGz in vitro and in vivo. Methods The expression plasmids of pHA-HBx encoding full length of HBx gene was transfected into HepG2 cells with Lipofectamine 2000. The proliferation activity of transformed cells was measured by calculating the growth curve,population doubling time and by the 3H-TdR incorporation rate assay. The nude mouse model of HepG2 expressing HBX gene was established and the apoptosis rate of tumor cells was detected with TUNEL assay. Results RT-PCR indicated that the HBx gene was integrated into the genome DNA of HepG2 cells and transcripted. The growth curve and population doubling time manifested that the proliferation activity of transformed cells was much higher than that of control group cells. The apoptosis rate of tumor cells expressing HBx gene was much lower than that of control group cells. ConclusionHBx facilitates the proliferation activity of hepatoma cells in vitro and in vivo and inhibits the apoptosis of hepatoma cells induced by adriamycin in nude mice.

Objective To investigate the changes in the expression of neuromedin U receptor 2 (NMUR2) in spinal dorsal horn in a rat model of bone cancer pain (BCP).Methods Thirty-two female Sprague-Dawley rats,weighing 150-180 g,were randomly divided into 2 groups (n =16 each):sham operation group (group S) and BCP group.BCP was induced by inoculating Walker 256 mammary gland carcinoma cells (1 × 105) into the medullary cavity of left tibia.Heat-killed Walker 256 cells (1 × 105) were injected into the medullary cavity of left tibia in S group.Eight rats were chosen from each group and the paw withdrawal threshold (PWT) to yon Frey filaments was measured at 1 day before operation (baseline) and 1,3,6,9,12 and 15 days after operation.Bone destruction was shown by X-ray at 15 days after operation.At 1 day before operation and 15 days after operation,4 rats in each were chosen and sacrificed,and L4,5 segments of the spinal cord were removed for measurement of the expression of NMUR2 mRNA (by real-time PCR) and protein (using Western blot analysis) in the spinal dorsal horn.Results Compared with S group,the PWT was significantly decreased at day 6-15 after operation and the expression of NMUR2 mRNA and protein in the spinal dorsal horn was up-regulated at 15 days after operation in BCP group (P ＜ 0.05 or 0.01).Compared with the baseline value,the PWT was significantly decreased at day 6-15 after operation and the expression of NMUR2 mRNA and protein in the spinal dorsal horn was up-regulated at 15 days after operation in BCP group (P ＜ 0.05 or 0.01).X-ray showed defect of bone trabecula and cortical bone destruction in BCP group.Conclusion The expression of spinal NMUR2 is up-regulated in rats with BCP and this change may be involved in the development and maintenance of BCP.

ObjectiveControl study on the clinical efficiency and costs of fast track surgery(FTS) and traditional method was carried out in colorectal cancer patients. Methodsone hundred colorectal cancer patients were randomLy selected, 50 cases treated with conventional therapy as control group and 50 cases treated with FTS programme. The postoperative initial venting time, the incidence of complications, the hospital stay and cost index were compared between the two groups. ResultsThe postoperative initial venting time was in advance and postoperative stay was obviously shortened in FTS group. Hospitalization expenditure in FTS group was lower than that in control group. Patients recovered quickly, the result was satisfactory. The complication was not significantly different between the two groups (P ＞ 0.05 ) . ConclusionsFTS treatment can accelerate postoperative rehabilitation and elevate clinical efficiency in colorectal cancer patients during operation period. FTS treatment is a safe and effective method.

Objective To explore the related risk facts of pulm onary throm boem bolism (PTE ) and analyze the relation betw een PTE and the traum a or m edical behavior by investigating the cases of PTE . Methods Thirty-three cases w ere selected from Institute of Forensic Science (IFS) from 2000 to 2014. Results In 33 cases, 16 decedents w ere m ale, 17 decedents w ere fem ale;different degrees of dyspnea, chest tight-ness and syncope sym ptom s w ere the clinical m anifestation of the deceased; the throm bus w as mainly distributed in the left and right pulm onary arteries. The main source of em bolism w as the deep vein of low er lim b and the left probability w as higher. Traum a, lim ited position, operation and cardiovascular disease show ed high-risk factors of PTE; D-D im er test, hem olytic test and com puter tom ography pul-m onary angiography w ere the diagnostic tools for PTE . In som e cases, traum a and m edical m alpractice could be involved in the cause of death. Conclusion N on-typical clinical sym ptom s present in the m ost cases caused by PTE , and these cases alw ays show m any high-risk factors. The relation betw een PTE and injury or m edical behavior should be considered carefully in the forensic pathological practice.

BACKGROUND:Poly(3-hydroxybutyrate) is approved as its excel ent biocompatibility, biodegradability and piezoelectric properties, but there are also some deficiencies, such as high breakability and poor hydrophilicity. METHODS:Poly(3-hydroxybutyrate) was mixed with different mass percentages of nanohydroxyapatite (0, 10%, 20%and 30%) to prepare new composite fibrous scaffolds through electrospinning process. The microstructure, group composition, crystal ine phase distribution, thermal properties and surface wettability of the scaffolds were detected. RESULTS AND CONCLUSION:Under the scanning electron microscope, with the increase of nano-hydroxyapatite content, more and more nano-hydroxyapatite particles were distributed evenly on the composite fiber surface;the fiber surface was basical y covered with nano-hydroxyapatite particles at the content of 30%, and the roughness of the fiber surface also increased. Results from differential scanning calorimetry and X-ray diffraction showed that the nano-hydroxyapatite reduced the crystal inity of poly(3-hydroxybutyrate) and the crystal tacticity, and this phenomenon became more evident with the increase of nano-hydroxyapatite content. Additional y, the higher the content of nano-hydroxyapatite content, the lower the contact angle and the higher the hydrophily. These findings indicate that the nano-hydroxyapatite/poly(3-hydroxybutyrate) ultrafine-fibrous scaffold using electrospinning technology can effectively improve the surface wettability and crystal inity of the material as wel as the material hydrophily and brittleness, and the higher the content of nano-hydroxyapatite, the more obvious the effect.