Objective To observe the biomechanics of the anterior and posterior interosseous talo-calcaneal ligaments (ITCLs) . Methods Load-displacement characteristics of the subtalar joint were studied in 12 cadaver specimens whose ankle joints were mutilated. The ankle articular surfaces of the talus and the post-calcaneus were exposed. Bone blocks were then embedded in polymethylmethacrylate. The an-terior ITCLs were abscised in 6 of them, and the posterior ITCLs in the other 6. A multi-functional biome-chanical machine was used to perform the biomechanical tests on the specimens. Results When the anterior ITCLs were cut, the tali moved to the anterior-lateral side. When the posterior ITCLs were cut, the tali mostly moved to the anterior-interior side. Conclusions The anterior and posterior ITCLs have dif-ferent roles in maintaining stability of the subtalar joint. Since the posterior ITCLs seem more important than the anterior ones, they should have priority in ITCL reconstruction.

Objective To explore the clinical value of microsurgery in the treatment of lateral ventricle tumors. Methods Microsurgery was conducted in 14 cases of lateral ventricle trmors in this department from May 1996 to August 2002. According to the location of tumors, we selected the approach close to the focus, protected the surrounding nerve tissue and the deep venous system, and resected the tumor in fractions. Results Among the 14 cases, 13 (92.9%) received total resection and 1 (7.1%) subtotal resection. A total of 11 cases of complications occurred postoperatively, including 3 cases of intracranial infection, 2 cases of hemiparalysis, 1 case of hydrocephalus, 3 cases of frontal lobe mental symptoms, 1 case of intraventricular hematoma and 1 case of nominal aphasia. Except for 1 case of hemiparalysis who were not able to resume the ability to take care of his own basic needs, the remaining 10 cases obtained full recovery. Follow-up in 9 cases for 6～60 months (mean, 29 months) showed 2 cases of recurrence of astrocytoma. Conclusions Microsurgery offers good visualization, minimal invasion and a high total resection rate for tumor.

Digital angiography system is mainly composed of Digital Subtraction Angiography(DSA)equipment and mostly used in angiography and interventional radiology.With the improvement of image quality,modern DSA equipment has a higher radiation output capacity,which increases the potential radiation damage to the operators and patients.Dose optimization studies the relationship between image quality and radiation dose for reasonable reduction of radiation dose and good image quality.

Objective To observe the effect of acute hypervolemic hemodilution(AHH) combined with nicardipine controlled hypotension on hemodynamics changes in revision operation of total hip replacement.Methods Forty patients were divided into two groups according to the sequence of the surgery(odd number came into group A,even number came into group B,20 in each group).In group A,AHH was carried out with nicardipine controlled hypotension;group B was control group.AHH was carried out in both groups before anesthesia induction.6%voluven was transfused in group A at 15 mL?kg-1 and 30 mL?min-1 and nicardipine was transfused at 0.3-0.5 mL?kg-1?h-1 with MAP altering between 60 and 65 mmHg;Same quantity of physiological saline was transfused in group B.HR,MAP,CVP,Hb,Hct and Plt were recorded and observed at preoperation,1 h after AHH and 24 h after the operation.Results In group A after AHH with nicardipine controlled hypotension,MAP was obviously lower than pre-operation(P

Objective To investigate the killing effect and molecular mechanism of different doses of ~(125)I seed interstitial brachytherapy for human hepatoma HepG2 cells in nude mice transplanted tumor.Methods Twenty nude mice bearing human hepatoma HepG2 cells were randomly divided into 4 groups (each n=5) and given ~(125)I seed interstitial brachytherapy at different doses including 18.5 MBq ~(125)I,29.6 MBq ~(125)I,37.0 MBq ~(125)I and 0 (the control group) ,respectively.~(125)I seeds were percutaneously implanted into tumors,each mouse with 1 ~(125)I seed implanted.Twenty-eight days later,nude mice were sacrificed and routine pathological examination was performed,.The expression of Bcl-2 and Bax was detected with immunohistochemical methods.Results Pathological examination showed serious coagulation necrosis of tumor cells surrounded by extensive fibrosis in all treatment groups,whereas rich tumor cells with proliferative growth were observqed in the control group.Immunohistochemical analysis showed that the expression of Bax in all treatment group were higher than that in the control group.the expression of which was up-regulated with increasing doses of ~(125)I seed.The expression of Bcl-2 and the ratio of Bcl-2/Bax in all treatment groups were lower than those in the control group.the expression of which was down-regulated with increasing doses of ~(125)I seed.The expression of Bcl-2.Bax and the ratio of Bcl-2/Bax among treatment groups and control group had statistical difference (P＜9.05) ,so as the difference among treatment groups (P＜0.05) .Conclusion ~(125)I seed interstitial brachytherapy induces apoptosis in human hepatoma HepG2 cells by reducing the ratio of Bcl-2/Bax and thereby inhibits the growth of tumor in nude mice,and the extent positively correlates with dosage in a certain range.

Objective Production of autotoxin protein in sf9 insect cells with biological activity. Methods Autotaxin cDNA was cloned into pFastBacTMHTA from melanoma cell by extraction of total RNA using TRIzol method and RT-PCR. Bacmid-ATX is isolated from transformed competent bacterial DH10 which carries Bac genomic sequences and transfected into sf9 using lipofectamine 2000. Recombinant ATX virus was amplified in sf9 and further used for infection and expression of ATX protein. Two step purification product using HistrapTMHP and Hiload 16/600 Suerdex 200pg was determined for lysophospholipase D (lysoPLD) activity. Results Correct insertion of PCR fragment is confirmed by BamH I/Xho I digestion and sequencing. ATX virus can infect sf9 and induced enzymatic activity. Column purification and SDS-PAGE resulted 95% in purity and 6mg/liter in yield with significant lysoPLD activity. Conclusion ATX Baculovirus was successfully constructed that can infect sf9 cells and express active lysoPLD. Production of active ATX can be used for crystalography studies and screening for small pharmaceutical inhibitors.

Objective To investigate the effects and mechanism of prone ventilation in rats with lipopolysaccharide(LPS)-induced extra pulmonary acute lung injury(ALI). Methods Thirty-two male Sprague-Dawley(SD)rats were randomly divided into four groups:control group,ALI group,supine position group(ALIS group)and prone position group(ALIP group). The ALI animal model was reproduced by intra-peritoneal injection of LPS 6 mg/kg,and 2 mL/kg sterile saline was intra-peritoneally injected in control group. After 24 hours,the ALIS group and ALIP group were mechanically ventilated for 4 hours in supine and prone positions respectively. Arterial partial pressure of oxygen(PaO2),carbon dioxide partial pressure(PaCO2),wet to dry weight ratio of lung(W/D) were observed,and the levels of tumor necrosis factor-α(TNF-α),interleukins(IL-6,IL-10)in bronchoalveolar lavage fluid(BALF)were measured. The degrees of histopathological changes of lung were investigated and assessed under light microscope. Results Compared with control group,PaO2 was significantly lower in ALI,ALIS and ALIP groups〔mmHg(1 mmHg=0.133 kPa):68±7,82±8,93±7 vs. 116±7〕,and the PaCO2 in ALI and ALIS groups was obviously higher(mmHg:53±6,51±5 vs. 43±7,both P<0.05);lung W/D ratio as well as levels of TNF-α, IL-6 and IL-10 in BALF were significantly higher in ALI,ALIS and ALIP groups〔lung W/D ratio:5.11±0.32, 4.71±0.38,4.53±0.45 vs. 4.48±0.15,TNF-α(ng/L):548±82,431±64,347±53 vs. 162±16,IL-6(ng/L):772±119,587±178,490±139 vs. 127±16,IL-10(ng/L):211±43,295±36,352±59 vs. 104±31,all P<0.05〕. Compared with ALI group,PaO2 in ALIS and ALIP groups was significantly higher,and in ALIP group,PaCO2 was lower,lung W/D ratio,TNF-α and IL-6 in BALF were obviously lower,while IL-10 in BALF was obviously higher(all P<0.05). Compared with ALIS group,the changes in ALIP group were more significant(all P<0.05). Compared with ALIS group,under light microscope,it was shown that the hyper-inflated areas were less,normal and collapsed areas were greater on the ventral side,and the collapsed area was less and the normal ventilation area was greater on the dorsal side in ALIP group(all P<0.05). Conclusion In rats with LPS-induced extra pulmonary ALI,the prone ventilation can improve gas exchange,promote uniform distribution of ventilation,decrease pulmonary edema and in the mean time attenuate inflammatory response.

Objective To analyze the relevantly risk factors of cerebral arteriovenous malformation (AVM ) with hemorrhage . Methods The clinical data of 127 patients with cerebral arteriovenous malformation were retrospectively analyzed .71 patients with hemorrhage were divided into the hemorrhage group while 56 patients without hemorrhage were divided into the control group .The clinical data of the two groups were compared and analyzed .Results Univariate analysis indicated that the differences of location and size of the AVM masses ,location of the feeding arteries ,direction of the draining vein ,combining with aneurysms and size of aneurysms were statistically significant (P<0 .05) .When stepwise multiple logistic regression analysis was employed ,deep AVM masses ,small-sized AVM masses(<3 cm) ,deep draining veins and combining with aneurysms were dependent predictors of hemor-rhagic presentation(P<0 .05 ,OR>1) .Conclusion The patients with deep AVM masses ,small-sized AVM masses(<3 cm) ,deep draining veins and combining with aneurysms should be operated as soon as possible to avoid hemorrhage .

Objective To investigate the effect of isoflurane preconditioning on Toll-like receptor 4 (TLR4)-myeloid differentiation factor 88 (MyD88) signaling pathway in ischemic penumbra following focal cerebral ischemia-reperfusion (I/R) in rats.Methods Fifty-four healthy male SD rats,aged 3 months,weighing 250-280 g,were randomly divided into 3 groups (n =18 each):sham operation group (group S),I/R group and isoflurane preconditioning group (group IP).Focal cerebral I/R was induced by middle cerebral artery occlusion.In groups I/R and IP,a nylon thread with rounded tip was inserted into the right internal jugular vein and threaded cranially until resistance was met.The middle cerebral artery was occluded for 2 h,followed by 24 h reperfusion.In group IP,the animals inhaled 2.0％ isoflurane for 2 h,and middle cerebral artery occlusion was performed at 24 h after the end of preconditioning.Neurological deficit was scored at 24 h of reperfusion and then the rats were sacrificed.Five rats in each group were chosen and the brains removed for measurement of the cerebral infarct volume.The right cerebral ischemic penumbra was removed for detection of the expression of HSP60,TLR4,MyD88 protein and mRNA by Western blot analysis and real time-PCR.Apoptosis was detected in the ischemic penumbra in the left 3 rats in each group using TUNEL.Apoptosis index (AI) was calculated.Results Neurological deficit scores and AI were significantly increased,the cerebral infarct volume was significantly enlarged,and the expression of HSP60,TLR4,MyD88 protein and mRNA was up-regulated in groups I/R and IP as compared with group S ( P ＜ 0.05).Isoflurane preconditioning significantly reduced the cerebral infarct volume and decreased neurological deficit scores and AI,and down-regulated the expression of HSP60,TLR4,MyD88 protein and mRNA (P ＜ 0.05).Conclusion The mechanisn by which isoflurane preconditioning protects ischenic penumbra following focal cerebral I/R may be related to inhibition of TLR4-MyD88 signaling pathway.