Objective To evaluate the effect of propofol on lung cell apoptosis induced by acute pulmonary thromboembolism (APTE) .Methods Forty male SD rats weighing 280-300 g were randomly divided into 5 groups ( n = 8 each) : group Ⅰ sham operation ( group S) ; group ⅡAPTE and 3 propofol groups ( group P1-3). APTE was produced by iv injection of auto-blood clots. Venous blood 0.2 ml was obtained from rat tail vein and placed in a sterile test tube which was kept in water bath at 37 ℃ overnight. The blood clot was cut into thrombi ( diameter 1 mm, length 5 mm) the next day. Fifteen thrombi in 2 ml of normal saline were injected into immediately after iv injection of auto-bloed clots. The animals were killed at the end of 4 h propofol infusion and lung specimens were obtained for determination of lung cell apoptosis rate by flow eytometry and expression of caspase-3, Bax, Bcl-2, Fas, FasL mRNA and protein by RT-PCR and Western blot.The expression of Bcl-2/Bax mRNA and protein was calculated. Results Compared with group S,APTE significantly increased the lung cell apoptosis rate, and expression of caspase-3, Bax, Fas, FasL and decreased the expression of Bcl-2 and Bcl-2/Bax. Propofol infusion significantly attenuated these APTE-induced changes. Conclusion Propofol can inhibit APTE-induced lung cell apoptosis by down-regulating the caspase-3, Fas and FasL expression and regulating the balance between Bcl-2 and Bax expression.

There are some shortcomings of animal experiments applied in chemical toxicity testing, such as long period, large cost, species differences and dose differences, which limit the use of animal experiments' results in predicting human toxicity.Accordingly, we established a toxicity testing alternative screening system in line with the toxicity endpoints which required in chemical safety evaluation and risk assessment (genotoxicity, carcinogenicity, reproductive toxicity, acute toxicity and general toxicity) based on 3R principles (replacement, reduction, refinement) for animal experiments.This system covers most of the endpoints of toxicity assessment, and molecular biology technology was also applied to integrate the toxicity test, as well as some operation was optimized in order to shorten the experimental period, reduce experimental costs, improve animal welfare.Furthermore, the results from the screening system have higher clinical relevance because it is based on the toxicity mechanisms.

In view of the characteristics of the computerized system,the key points in the quality assurance (QA) of the computerized system was discussed and summarized combined with the requirements of the GLP laboratory in Europe and America.The validation of computerized system,the control during the use of computerized system,period maintenance and safety protection of computerized system,archives of electronic data was discussed,expecting to provide reference for the management of computerized system in Chinese GLP laboratory which is generally not high currently.The experiences were obtained as follow:Through repeated inspection and review,the problem was found and set as the risk point;a targeted QA inspection plan was made focusing on the risk-based inspection and the QA inspection plan was timely adjusted according to the problems,which ensures the pertinence and validity of the QA inspection.

Objective To investigate the mechanism of retinal injury in rats caused by light-emitting diodes(LEDs)with different color rendering indexes(CRIs).Methods Totally 20 Sprague-Dawley rats were randomly divided into nor-mal control(NC)group(sunlight),low CRI(CRI-L)group(blue light),medium CRI(CRI-M)group(conventional LED),and high CRI(CRI-H)group(full-spectrum LED),with 5 rats in each group,exposed to light for 12 hours daily for 4 consecutive weeks.Hematoxylin & eosin staining was used to assess morphological changes in the retina.Dihydroethidi-um staining was employed to detect the levels of reactive oxygen species(ROS)in retinal tissues.The messenger ribonu-cleic acid(mRNA)expressions of NOD-like receptor family pyrin domain containing protein 3(NLRP3),Gasdermin D(GSDMD)and Caspase-1 were analyzed by real-time quantitative polymerase chain reaction(RT-qPCR),and their protein expressions were measured through immunohistochemical staining.Environmental light spectra were measured using a spectroradiometer.Results Rats in the CRI-L group showed the thinnest retina,followed by the CRI-M group and CRI-H group.The fluorescence intensity of ROS in the NC group,CRI-L group,CRI-M group and CRI-H group was 1.000±0.046,25.060±1.732,14.530±3.776 and 1.821±0.587,respectively.The ROS level in the CRI-H group was significantly lower than that in the CRI-L group and CRI-M group(both P＜0.05).RT-qPCR showed that the relative mRNA expression of NL-RP3 in the NC group,CRI-L group,CRI-M group and CRI-H group was 1.004±0.005,4.004±0.716,2.027±0.303 and 0.741±0.069,respectively;the relative mRNA expression of Caspase-1 was 1.010±0.006,4.337±0.345,2.268±0.058 and 0.713±0.021,respectively;the relative mRNA expression of GSDMD was 1.000±0.000,2.938±0.559,1.955±0.166 and 1.213±0.051,respectively.Compared with the NC group,the relative expressions of NLRP3,Caspase-1 and GSDMD in the CRI-L group and CRI-M group significantly increased(all P＜0.05).The immunohistochemical staining results showed that the fluorescence intensity of NLRP3 in the retina of rats in the NC group,CRI-L group,CRI-M group and CRI-H group was 0.379 4±0.002 2,0.400 7±0.011 4,0.379 0±0.006 9 and 0.377 0±0.007 5,respectively;the fluorescence intensity of Caspase-1 was 0.367 2±0.005 8,0.442 6±0.041 1,0.382 4±0.011 9 and 0.380 6±0.006 5,respectively;the fluorescence intensity of GSDMD was 0.159 5±0.013 4,0.167 5±0.011 9,0.397 6±0.014 3 and 0.377 2±0.022 8,respec-tively.Compared with the NC group,rats in the CRI-L group showed increased fluorescence intensity of NLRP3 and Caspase-1,and rats in the CRI-M and CRI-H showed increased fluorescence intensity of GSDMD(all P＜0.05).The spec-tral comparison revealed that the CRI-H group had a broader spectral coverage and a distribution closer to natural light spectra.Conclusion Conventional LED exposure can induce a decrease in retinal thickness,upregulate the ROS expres-sion in retinal tissues,and increase the expression levels of NLRP3,Caspase-1 and GSDMD.High CRI full-spectrum LEDs can mitigate pyroptosis through the ROS/NLRP3 pathway by optimizing their spectral distribution,offering better biosafety.