Expression of proteasome activator REGγ in human laryngeal carcinoma and associations with tumor suppressor proteins.

The functional significance of the proteasome activator REGγ in the regulation of cell proliferation and apoptosis has been recognized. However, pathological contributions to tumor development remain to be elucidated. Both oncogenic proteins and tumor suppressors are targeted by REGγ for proteasomal degradation. It has been proposed that the role of the REGγ in the pathogenesis of cancer is cell- and context-specific. In this study, we aimed to explore the potential involvement of REGγ in laryngeal carcinomas, comparing protein expression in tumor and adjacent tissues by immunohistochemical staining and Western blot analysis. We also characterized the correlation between the expression of REGγ and the previously identified substrates p53 and p21. We showed that REGγ was abnormally highly expressed in cancer tissues. Statistical analysis revealed that there was a positive relationship between the level of REGγ and the expression of p53 and p21. Our study suggests that REγ overexpression can facilitate the growth of laryngeal cancer cells.

[Effect of PTU on the expression of thyroid TPO, Tg mRNA in rats].

OBJECTIVE: To explore the mechanism and the compensation proceeding of thyroid hyperplasia caused by PTU. METHODS: PTU was administered to rats by gavage at a dose of 5.0 mg/kg B. W for 3, 6, 9, 12, 15, 18, 21 days respectively. All animals were sacrificed after the last dosage, and the expression of TPO and Tg in thyroid was detected by RT-PCR. The serum thyroid hormones were measured by chemoluminescence. RESULTS: Compared with the control group, the TPO mRNA levels of PTU groups were increased, while the Tg mRNA levels were decreased significantly. Serum TT3, TT4 in rats treated with PTU demonstrated a descending trend, while serum TSH showed an ascending trend, and the significant differences were observed after 6 days treating with PTU. CONCLUSION: The interference of PTU on thyroid may relate to inhibiton of Tg gene transcription. The enhancement of TPO gene transcription can't compensate the thyroid function sufficiently.

[Effects of Panax notoginseng saponins on anti-hyperglycemic, anti-obese and prevention from kidney pathological changes in KK-Ay mice].

OBJECTIVE: To observe the effects of Panax notoginseng saponins (PNS) on anti-hyperglycemic, anti-obese and prevention from kidney pathological changes in a type 2 diabetic KK-Ay gene mice model. METHODS: All animals were divided into 4 groups: Normal control group (C57BL/6J mice) were treated by NS 10 mL/kg, KK-Ay mice were subdivided into 3 groups as DM administrated NS 10 mL/kg, PNS 50 mg/kg, PNS 200 mg/kg respectively. All the animals received daily intraperitoneal injections for 30 days consecutively. All of these following items were determined as the effect of PNS: fasting plasma glucose levels (FPG), intraperitoneal glucose tolerance, body weight, food intake, insulin resistance index (IRI), serum insulin, triglyceride (TG), cholesterol (CH) levels and contribution of glomerulus injury. RESULTS: On the 12th, 22nd and 30th day, PNS-treated group had significantly lower FPG and low body weight incremental percentage. After a 12-day treatment, glucose tolerance was significantly improved. On the 30th day the serum IRI and TG levels of PNS-treated group decreased significantly, and the development of the mice glomerular lesions was prevented significantly. All of these showed a dose-effect relationship. CONCLUSION: PNS has the effects of anti-diabetes, anti-obese and prevention from kidney pathological changes in type 2 diabetic KK-Ay mice.

[The expressions of HSP 70 mRNA and c-fos mRNA in the skeletal muscle and cardiac muscle of rabbits by electrocuted].

OBJECTIVE: To study the changes of HSP 70 mRNA and c-fos mRNA expression and to find a method to differentiate antemortem from postmortem electrocution. METHODS: Fifteen New Zealand rabbits were randomly divided into three groups, the antemortem electrocution group, the postmortem electrocution group, and the control group. Each group consists of five rabbits. The levels of HSP 70 mRNA and c-fos mRNA in skeletal muscle and cardiac muscle were examined with quantitative fluorescent RT-PCR. RESULTS: The levels of HSP 70 mRNA and c-fos mRNA in the antemortem electrocution group increased significantly (P<0.05), compared with that of the postmortem electrocution group. CONCLUSION: The changes of HSP 70 mRNA and c-fos mRNA expression in skeletal muscle and cardiac muscle can be used as an indicator to distinguish antemortem from postmortem electrocution.

[Study of adiponectin expression in placenta and its correlation with preeclampsia].

OBJECTIVE: To investigate the expression of adiponectin in placenta and its correlation with preeclampsia. METHODS: Placental tissues were collected from normal term pregnancies (normal pregnancy group, n = 20), mild preeclampsia (mild preeclampsia group, n = 12) and severe preeclampsia (severe preeclampsia group, n = 22). The expression of adiponectin protein and the intensity of its mRNA in placenta were detected using immunohistochemistry and RT-PCR, respectively. Integral optical density (IOD) which represents the expression level of adiponectin protein, and the ratio of adiponectin cDNA PCR products to beta-actin cDNA PCR products which represents the intensity of transcription of adiponectin mRNA in placenta were analyzed. RESULTS: (1) The expression of adiponectin protein was observed in cytoplasm of placental cytotrophoblasts and syncytiotrophoblasts among three groups. There was no significant difference in adiponectin protein expression between maternal side and fetal side of placenta in three groups (all P > 0.05); (2) The expression of adiponectin protein in placenta in severe preeclampsia group (30 984 +/- 14 604) was significantly lower than that of mild preeclampsia group (58 360 +/- 8910, P < 0.01) and of normal pregnancy group (53 246 +/- 17 554, P < 0.01). There was also no significant difference in the expression of adiponectin protein in placenta between term delivery and preterm delivery in severe preeclampsia group (38 890 +/- 20 386 vs 29 319 +/- 8997, P > 0.05), however, the expression of adiponectin protein in placenta in term delivery of severe preeclampsia group was significantly lower than that of term delivery of normal pregnancy group (38 890 +/- 20 386 vs 53 246 +/- 17 554, P < 0.05); (3) The expression of adiponectin mRNA was detected in placental tissues among three groups also. The intensity of transcription of adiponectin in placenta in severe preeclampsia group (1.0 +/- 0.2) was markedly lower than that of mild preeclampsia group (2.9 +/- 0. 8, P < 0.05) and normal pregnancy group (3.3 +/- 1.1, P = 0.000). CONCLUSION: The expression of adiponectin decreases in placenta tissues of severe preeclampsia, indicating that the abnormal expression of adiponectin may be involved in the pathogenesis of preeclampsia.

[Study on preventing effects of procyanidins on selenite cataract development in rats].

OBJECTIVE: To study the preventing effects of procyanidins (PC) on selenite cataract in rats and the time-effect relationship. METHOD: Forty five SD rats were divided into three groups: control, model and experiment groups. The rats in the experiment group were fed additionally with the PC by 80 mg x kg(-1) when they were supplied the equal selenite with the model group. Five rats of each group were regularly sacrificed by bleeding from femoral artery at sixth, eleventh, sixteenth day and the level of malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) of all lenses was measured. RESULT: Compared with the model group, the level of the MDA in the experiment group at the eleventh day and the sixteenth day greatly decreased (P < 0.01). At the sixteenth day the level of the SOD and GSH-Px had an increase (P < 0.01), which showed its anti-oxygenation. CONCLUSION: PC indicated the obvious inhibition in the development of the rat cataract. The treatment period was recommended at least for fifteen days.

Endothelial cell membrane perforation of aorta and pulmonary artery in the electrocution victims.

Some electrocution deaths occur without detectable current marks on the skin, making forensic examination to determine the true cause of death more difficult. Because arterial thrombosis was a frequent finding in victims of electrocution, we investigated injury to the endothelium of the aorta and pulmonary artery with a scanning electron microscope in five cases of death known to be caused by electrocution. We found large pores on the surface of endothelial cells of the aorta and pulmonary artery in those who died of electrocution, but no endothelial membrane perforation was found in those who died of cardiac diseases. These findings were present within 12h after death. Therefore, scanning electron microscopic evidence of endothelial perforation in the aorta and pulmonary artery could be a useful marker to identify electrocution for those victims without detectable current marks on the skin.

[The expression rule of proliferating cell nuclear antigen in rat thyroid of hyperplasia induced by propylthiouracil].

OBJECTIVE: To study the expression rule of proliferating cell nuclear antigen (PCNA) in thyroid when the hyperplasia of male rat thyroid is induced by propylthiouracil (PTU). METHODS: PTU was administered to rats by gavage at a dose of 5.0 mg/kg B. W for 0,3,6,9 and 12 days respectively. All animals were sacrificed after the last dosage, and the expression of PCNA in thyroid was detected by immunohistochemistry and RT-PCR. RESULTS: Compared with the control group, the PCNA level in the thyroid of rats given PTU for 3 days significantly increased (P < 0.05),and reached the highest expression when it was 6 days, but then when it was 9 days and 12 days, the PCNA expression showed a descending tendency. CONCLUSION: PCNA has a expression rule in hyperplastic thyroid: expression increase first but then decrease. This rule confirms the histological change of thyroid in earlier stage. The experimental time of assessment test to thyroid hormone disruptors will be shortened to six days.

[Time course of the disruption of rat's thyroid function by pesticide N'N-methylene-bis].

OBJECTIVE: To study the effect of pesticide N'N-methylene-bis on thyroid function in rats, and the time-effect relationship. METHODS: N'N-methylene-bis dimethylsulfoxide solution was administered to rats by gavage at a dose of 50 mg/kg body weight for 1, 3, and 5 days respectively. The rats in the control group were given solvent dimethylsulfoxide by oral gavage at the same volume. All animals were sacrificed 1 day after the last dosage, and the levels of FT4 and TSH in serum were measured by radioimmunoassay. The histological changes of thyroid gland were observed, and the expression of PCNA in thyroid was detected by immunohistochemistry. RESULTS: Compared with the solvent control group, the serum FT4 level in rats given N'N-methylene-bis for 3 days significantly decreased, while the TSH level significantly increased in the 3 d and 5 d groups (P<0.05). Hyperplasia of thyroid follicular epithelium was observed in the 3 d and 5 d groups. PCNA positive cells in thyroid of the 3 d and 5 d groups were significantly higher than that of control (P<0.05). CONCLUSION: The effect of N'N-methylene-bis on the level of serum FT4 and TSH in rats appeared on the 2nd or 3rd day of the experiment. Histopathologic examination showed thyroid gland proliferation of follicular epithelium within 3 days. The combined use of serologic test and histopathologic examination for screening thyroid hormone disruptors may be an effective method.

[Impact of traditional Chinese medicine WPY on ICAM-1 expression and MPO activity in pancreas and lungs of rats with acute necrotizing pancreatitis].

OBJECTIVE: To explore the character of the ICAM-1 induced change of polymorphonuclear neutrophil (PMN) in the pancreas and lung of rats with acute necrotizing pancreatitis (ANP) and to evaluate the effects of Chinese medicine WPY on ANP. METHODS: ANP model was induced by retrograde injection of 3.5% sodium taurocholic acid into the biliopancreatic duct of Wistar rats. Expression of ICAM-1 at different time points in pancreas and lung was assessed by immunohistochemistry. The quantity of polymorphonuclear neutrophil (PMN) in tissues was measured by the level of myeloperoxidase activity (MPO). In addition, the indices above were also observed after the administration of WPY. RESULTS: In the ANP group, ICAM-1 expression and MPO activity were evidently up-regulated at 3 h in pancreas and at 6 h in lung, and both reached their highest level at 12 h. In the WPY treated group, ICAM-1 expression and MPO activity in pancreas and lung were significantly decreased at 12 h. CONCLUSION: The numerous PMNs infiltration mediated by ICAM-1 plays an important role in the damage to pancreas and lung caused by ANP. The traditional Chinese medicine WPY can attenuate ICAM-1 expression and MPO activity in pancreas and lung during ANP.

[Exploring the sensitive indicators of uterotrophic assay in immature SD rats exposed to para-nonylphenol].

OBJECTIVE: To investigate the estrogenic activity of para-nonylphenol in immature SD rats and explore the mechanism and sensitive indicators of its action in uterotrophic assay. METHODS: The vehicle control (peanut oil), positive control(estradiol benzoate, E2B, 0.4 mg/kg) and p-NP(60 mg/kg, 90 mg/kg and 120 mg/kg) were given orally (by gavage) q.d. on the 21st, 22nd, 23rd postnatal days. Then the rats were sacrificed 24 hours after the last administration. By using ABC immunohistochemistry, the progesterone receptor (PR), estrogen receptor (ER), and proliferating cell nuclear antigen (PCNA) of the rat uterine were analysed. RESULTS: Uterine weight, uterine/body weight significantly increased in E2B 0.4 mg/kg, p-NP 90 mg/kg and 120 mg/kg groups as compared with those of vehicle control group (P < 0.01), and a dose-response relationship was observed. The expressions of PR, ER and PCNA in the nuclei of stromal and myometrial cells of uterus were detected in all the p-NP groups, and a dose-effect relationship was noted. CONCLUSION: Expressions of PR, ER and PCNA as indicators tested by immunohistochemical technique are more sensitive than uterine weight in uterotrophic assay. Hyperplasia of stromal and myometrial cells of uterus is the reason why the uterine weight of the rat increased.