Objective To evaluatethe expression and significance of RUNX3 gene and protein in hepatocellular carcinoma.Method Reverse transcription-polymerase chain resction (RT-PCR) and immunoitistochemistry SP method were used to detect the expressions of RUNX3 gene and protein in 23 cases of hepatocellular carcinoma and their adjacent non-cancerous tissue.Results The expression of RUNX3 gene and protein were significantly reduced in hepatocellular carcinoma tissue (26.1% and 17.4% respectively),which were prominently lower than those in adjacent non-cancerous tissue:91.3% (21/23) and 87.0% (20/23),P＜0.01.Conclusion The lower-expression of RUNX3 gene and protein may play an important role in hepatocellular carcinoma.

To improve the quality of experimental teaching,investigating the independent design experiments are carrying out in preventive medicine by public health experimental teaching center in our school.We take preventive medicine professional as an example,and besides the classical basis experiments,some experiments are verification project at present,in which students are not strongly interested.On the basis of the integration of the classic experiments,according to the national standard of the experimental method,we are trying to carry out part of the independent design experiments to meet the needs of students learning.The effect of those independent design experiments shows that it is appropriate carrying out independent design experiments on the basis of the existing classical experimental project in preventive medicine experimental teaching,to a certain extent,which will stimulate students' learning interest and enhance their sense of achievement.This study is conducive to the cultivation of medical students' innovation,independent thinking,analysis and problem-solving ability,practical ability and teamwork spirit.

Most of the current experiments are obsolete and verified,the students are not interested in and the experiments are out of touch with the actual work.These are the common problems in the experiment teaching of occupational health and occupational medicine.By taking the students who majored in preventive medicine as the subjects,this study aimed to explore the effects of independent designed experiment teaching mode,which was based on dividing the groups before class,choosing the projects by students themselves,deciding the design of the program via the discussion of teacher and students and doing the experimental reports and sharing the experience.The results showed that,in the premise of the preliminary master of the theory and basic skills of occupational health and occupational medicine,carrying out independent designed experiments in the last three weeks of semester,to a certain extent,could arouse students' interest in learning,cultivate their abilities of independent thinking,practice,problem analysis and solution,and team cooperation.However,restricted by lack of teachers,inadequate equipment and high cost and other factors,this teaching mode is only suitable for small class.

Objective To explore the protective effects of rutin against learning and memory impairment induced by trimethyltin (TMT) and investigate the possible mechanism. Methods Forty 6- to 9-week-old male BALB/c mice were randomized equally into saline group (control), TMT group, TMT+rutin group, and rutin group. Mouse models of learning and memory impairment were establish by acute TMT (2.25 mg/kg) exposure. In TMT+rutin and rutin treatment groups, the mice received intraperitioneal injection of rutin (10 mg/kg) for 1 week before TMT exposure. Twenty-four hours after TMT exposure, Morris water maze test was employed to test the escape latency of the mice, and the synaptophysin expression in the hippocampus and cortex were analyzed by Western blotting. Results Compared that in TMT group, the escape latency of the mice in water maze test was significantly shorter in the other 3 groups (P<0.05);the escape latency in TMT+rutin group was similar with that in the control and rutin groups (P>0.05). Western blotting showed significantly decreased synaptophysin expression in the hippocampus and cortex in TMT group (P<0.05); synaptophysin expression in TMT+rutin group increased significantly compared with that in TMT group (P<0.05) but showed no statistical significance from that in rutin and control groups (P>0.05). Conclusion Rutin pretreatment offers protective effect against TMT- induced learning and memory impairment in mice possibly by antagonizing decreased synaptophysin in the hippocampus and cortex.

Objective To explore the protective effects of rutin against learning and memory impairment induced by trimethyltin (TMT) and investigate the possible mechanism. Methods Forty 6- to 9-week-old male BALB/c mice were randomized equally into saline group (control), TMT group, TMT+rutin group, and rutin group. Mouse models of learning and memory impairment were establish by acute TMT (2.25 mg/kg) exposure. In TMT+rutin and rutin treatment groups, the mice received intraperitioneal injection of rutin (10 mg/kg) for 1 week before TMT exposure. Twenty-four hours after TMT exposure, Morris water maze test was employed to test the escape latency of the mice, and the synaptophysin expression in the hippocampus and cortex were analyzed by Western blotting. Results Compared that in TMT group, the escape latency of the mice in water maze test was significantly shorter in the other 3 groups (P<0.05);the escape latency in TMT+rutin group was similar with that in the control and rutin groups (P>0.05). Western blotting showed significantly decreased synaptophysin expression in the hippocampus and cortex in TMT group (P<0.05); synaptophysin expression in TMT+rutin group increased significantly compared with that in TMT group (P<0.05) but showed no statistical significance from that in rutin and control groups (P>0.05). Conclusion Rutin pretreatment offers protective effect against TMT- induced learning and memory impairment in mice possibly by antagonizing decreased synaptophysin in the hippocampus and cortex.

OBJECTIVE: To investigate the effect of benzo(α)pyrene on the ATPase activity and content of Ca²⁺ in the hippocampus of neonatal SD rats. METHODS: Sixty male and 60 female 4-days-old neonatal SD rats were randomly divided into 5 groups (n=24): a blank control group, a vehicle control group (peanut oil), 3 benzo(α)pyrene groups (0.02, 0.2 and 2 mg/kg, respectively). SD rats were given benzo(α)pyrene (dissolved in peanut oil) by gavage daily from postnatal day 4 (PND4) to PND20. The nerve reflex, the condition of neuro-muscle development and motion function were examined in the period of treatment. The colorimetric technique was used to detect the activity of Ca²⁺-ATPase and Ca²⁺-Mg²⁺-ATPase in hippocampus after the treatment. The concentration of Ca²⁺ of synapse in the hippocampus of rats was detected by fluorescent labeling. RESULTS: The results from the behavior tests showed that duration of surface reflex latency in rats with medium dose of benzo(α)pyrene was longer compared with that in the control group in PND12. The duration of surface reflex latency in rats with high dose of benzo(α) pyrene is longer in PND 14 and PND 16 compared with that in the control group (P<0.05). Compared with the rats in the control group, the activities of Ca²⁺-Mg²⁺-ATPase and Ca²⁺-ATPase in hippocampus in rats with high dose benzo(α) pyrene were significantly decreased, and the degree in the decrease of Ca²⁺-ATPase activity was dose-dependent (P<0.05). The contents of Ca²⁺ in the hippocampus in rats with medium or high dose of benzo(α) pyrene were significantly increased compared with that in the control group (P<0.05), which showed a dose-dependent manner (P<0.05). CONCLUSION Benzo(α)pyrene exposure led to the decrease in ATPase activity as well as Ca²⁺ overload of the synapse in the hippocampal tissue, which in turn results in the nerve damage of newborn SD rats.
Animals ; Benzo(a)pyrene ; toxicity ; Ca(2+) Mg(2+)-ATPase ; metabolism ; Calcium ; metabolism ; Calcium-Transporting ATPases ; metabolism ; Female ; Hippocampus ; enzymology ; Male ; Rats ; Rats, Sprague-Dawley