Aim: To investigate the pathological changes in NTBC[2-(2-nitro-4-trifluoro-methyl-benzoyl) -1,3 cy-clohexanedione]-induced hepatic injury in mice and in the repopulation of adult hepatocytes in Fah~(-/-) mouse. Methods: Autogenous hepatic injuries in Fah~(-/-) mice were induced by the treatment of NTBC. Injection of hepatocytes obtained from wild-type mice to spleen were transplanted into the Fah~(-/-) mice. Then, changes to body weight and the likelihood of the transplanted Fah~(-/-) mice, and hepatic immunohistochemistry were ob-served. In addition, pathological changes to liver damage induced by NTBC treatment were analyzed under HE-staining microscopy and electron microscopy. Results: The surviving Fah~(-/-) mice subjected to hepatocyte trans-plantation were found to be healthy and in stable body weight. liver repopulation reached to 90% in the 8th week. Repopulating hepatocytes caused no alteration to histological structure of the recipient liver, and subacute hepatic injury occurred in the Fah~(-/-) mice after NTBC treatment. Electronic microscopy observations indicated that necrosis in the hepatocytes occurred at early stage and that apoptosis gradually appeared. It was also shown both necrosis and apoptosis co-existed in the same samples of interest at the following stages of the induced liver injury. Conclusion: Transplanted hepatocytes proliferated in Fah~(-/-) mice allow 90% of the hepatocytic repopula- tion. Repopulation renders normal hepatic function and structure in the recipient Fah~(-/-) mice, as a model of liver repopulation, could be applicable in study of stem cell derived hepatic cells in transplantation assay.

Objective Based on the principles of laser radiation protection, medical metroiogy and photoelectron technology, an automatic verification device and testing technology to provide verification and performance evaluation for laser protective spectacles and equipments which have the various functions in laser protection have been developed and established. Methods The current system comprises laser source, laser measuring instruments, software of computer detection and control and modules of optics and mechanics used in auxiliary equipment. By use of the verification device and the special test-recording method to be designed and studied by us, the measured data can be automatically acquired, processed, recorded, saved and printed and, furthermore, many parameters on protective performance of the measured laser protective spectacles can be tested and given. Results Laser wavelength of the verification apparatus are 1 064 nm and 532 nm, response range of wavelength is from 0.4 m to 1.1 μm, measuring range of laser energy is from 10-8 J to 0.3 J, measuring range of optical density for laser protective spectacles is from 0.1 to 8.0, stability is 0.21%, measuring uncertainty is 5%(k=2). Conclusion The automatic verification device is steady and reliable. The achieved performance indexes accord with the requirement of national standard on laser protection.

Objective To investigate the mechanism of renal injury induced by changes in flow shear stress (FSS) during renal ischemia/reperfusion (I/R).Methods 1.In vitro,HUVECs were divided into 4 groups:(1) HUVECs were loaded with 12 dyn/cm2 force for 30,45,and 90 min by using plate fluid chamber system.(2) Cells were loaded with FSS for 2 h,and then cultured for 1,3,8 and 12 h respectively;(3) HUVECs were pretreated with 0,1,2,4 and 8 mmol metformin and cultured for 24 h.(4) HUVECs in control group were cultured normally.The expression of p-AMPK/AMPK protein was detected by Western blotting in each group.2.In vivo,16 SD rats with successful establishment of IR model were randomly divided into 4 groups (n =4 in each group):(1) static cold storage (CS) group:isolated kidneys were stored for 4 h;(2) hypothermia machine perfusion (HMP) group:isolated kidneys were continuously perfused with 0 ℃ lactated Ringer's solution for 4 h;(3)metformin treatment group (Met-CS):metformin was intraperitoneally injected 3 days before surgery,and the isolated kidneys were obtained after cold preservation for 4 h;(4)rat kidneys of control group were just subjected to thermal ischemia for 30 min.The injury of renal tissue in each group was observed by TUNEL and HE staining.The expression and distribution of p-AMPK protein in renal tissues were detected by immunohistochemistry.The correlation between FSS loss and AMPK expression in kidney tissue was analyzed.Results The expression of p-AMPK in HUVECs could be up-regulated by FSS,and the expression of p-AMPK protein increased with the prolongation of time.After stopping FSS,the expression of p-AMPK protein in HUVECs gradually decreased with time (P＜0.05).Metformin could activate AMPK activity in a concentration-dependent manner (P＜0.05).The content of p-AMPK in renal tissue of HMP group was significantly higher than that of CS group (P＜0.05).The expression of p-AMPK in renal tissue of HMP group mainly distributed in the renal tubules,and few in glomerular endothelial cells and blood vessels.The apoptosis rate of renal tissue in HMP group was significantly lower than that in CS group (P＜0.05).In the HMP group,the damage of the renal tissue was mild,there was no swelling,and the renal tubules were slightly expanded.In the CS group,the renal tissue was severely damaged and the renal tubules were markedly swollen.Conclusion During the course of renal IR in rats,changes in FSS may affect renal tissue damage through the AMPK pathway.

Objective:To investigate the role and molecular mechanism of death receptor 5 (DR5) in early brain injury (EBI) after subarachnoid hemorrhage (SAH), as well as the neuroprotective effect of soluble DR5 (sDR5) on SAH.Methods:Experiment 1: SD rats were randomly divided into sham-operated group ( n=6) and SAH group (SAH model was established by carotid artery puncture, n=30), and the SAH group was further subdivided into post-SAH (6 h) group, post-SAH (12 h) group, post-SAH (24 h) group, post-SAH (48 h) group and post-SAH (72 h) group ( n=6); Western blotting was used to detect the expressions of tumor necrosis factor (TNF)-α and DR5; immunofluorescent DR5 and neuronal nuclear antigen (NeuN) double staining was used to evaluate the DR5 expression in neurons. Experiment 2: SD rats were randomly divided into sham-operated group, SAH group, Trail group (injected Trail agonist dordaviprone), and Trail+sDR5 group (injected dordaviprone+sDR5, n=6); at the 24 th h of successfully constructed SAH model, the caspase family protein levels were detected by Western blotting, and Tunel staining and immunofluorescent DR5 and Caspase-3 double staining were performed. Experiment 3: SD rats were divided into sham-operated group, SAH group, Trail group and Trail+sDR5 group ( n=6); long-term motor functions, by modified Gracia score, forelimb placement experiment, rotarod test and misstep experiment, were evaluated 5, 7 and 12 d after successfully constructed SAH model; and long-term learning and memory functions were detected by water maze experiment 14, 16, 18, 20 and 21 d after successfully constructed SAH model. Results:(1) Result of Experiment 1: the expressions of TNF-α and DR5 in sham-operated group, post-SAH (6 h) group, post-SAH (12 h) group, post-SAH (24 h) group, post-SAH (48 h) group and post-SAH (72 h) group were statistically different ( F=837.992, P<0.001; F=503.942, P<0.001), and these expressions peaked 24 h after SAH; immunofluorescent DR5 and NeuN double staining showed that DR5 was located in neurons after SAH. (2) Result of Experiment 2: compared with the SAH group and Trail group, the Trail+sDR5 group had significantly decreased levels of activated caspase-8, tBid and activated caspase-3, significantly decreased numbers of Tunel positive cells and DR5 and activated caspase-3 co-marked positive cells ( P<0.05). (3) Result of Experiment 3: compared with the SAH group and Trail group, the Trail+sDR5 group had significantly increased Garcia scores, decreased failure rate in forelimb placement experiment, prolonged duration of stick rotation, and decreased foot fault rate ( P<0.05), suggesting that sDR5 could improve the long-term motor function deficit after SAH; water maze experiment showed that 21 d after SAH, compared with the SAH group and Trail group, Trail+sDR5 group had significantly increased proportion of escape time in the original platform quadrat in total escape time and increased proportion of movement path in the original platform quadrat in total movement path after platform removal ( P<0.05), suggesting that sDR5 could improve long-term learning and memory impairment after SAH. Conclusion:The sDR5 can inhibit DR5-Trail-mediated neuronal apoptosis and improve long-term neurological functional deficits after SAH.