BACKGROUND:Several studies have demonstrated that JAK2 kinase plays an important role in myocardial protection by ischemic preconditioning and medicine preconditioning. OBJECTIVE:To investigate the effects of exercise preconditioning on JAK2 mRNA and protein expression in the rat heart and the underlying mechanism of action. METHODS:SD rats were randomly divided into control, exhaustive, exercise preconditioning, and exercise preconditioning + AG490 groups. Rats in the control and exhaustive groups were fed routinely for 3 days. Rats in the exercise preconditioning and exercise preconditioning + AG490 groups were subjected to intermittent treadmil exercise for 3 successive days to establish exercise preconditioning animal models. Rats in the exercise preconditioning + AG490 group were intraperitonealy injected with JAK2 inhibitor AG490 at 10 minutes before exercise preconditioning. After 3 days, rats in the exhaustive, exercise preconditioning, and exercise preconditioning + AG490 groups were subjected to exhaustive treadmil exercise. Serum levels of lactate dehydrogenase and creatine kinase isoenzyme were determined. JAK2 mRNA and protein expression in the rat myocardial tissue was detected by real-time fluorescent quantitative PCR and immunohistochemistry.RESULTS AND CONCLUSION:Compared with the control group, serum levels of actate dehydrogenase and creatine kinase isoenzyme were increased, and JAK2 mRNA and protein expression in the myocardial tissue was significantly increased in the exhaustive group (P < 0.05). Compared with the exhaustive group, serum levels of actate dehydrogenase and creatine kinase isoenzyme were decreased (P < 0.05), while JAK2 mRNA and protein expression in the myocardial tissue was increased in the exercise preconditioning group (P < 0.05). Compared with the exercise preconditioning group, serum levels of actate dehydrogenase and creatine kinase isoenzyme were increased (P < 0.05), while JAK2 mRNA and protein expression in the myocardial tissue was decreased in the exercise preconditioning + AG490 group (P < 0.05). The results confirm that exercise preconditioning plays its cardioprotective role through activating JAK/STAT signaling pathway, up-regulating the expression of JAK2 mRNA and protein in the cardiac tissue and aleviating myocardial ischemia injury.

BACKGROUND:Studies have indicated that the abnormal expression of tumor necrosis factorreceptor-associated protein 1 (TRAP1) is closely related to the occurrence and development of a variety of tumors. Therefore, targeted inhibition of TRAP1 expression has become an important target for the treatment or intervention of tumor growth. OBJECTIVE:To explore the effect of the TRAP1 gene silencing on the proliferation and apoptosis of human laryngeal squamous cel carcinoma stem cel s. METHODS:CD24-CD44-human laryngeal squamous cel carcinoma stem cel s were isolated by flow cytometry. Interfering RNA (siRNA) sequences for smal molecule TRAP1 gene was designed and transferred into human laryngeal cancer stem cel s by LipofectamineTM 2000. Flow cytometry, MTT assay, cel clone formation assay and TUNEL apoptosis assay were used to evaluate the effect of silencing TRAP1 gene on the proliferation and apoptosis of CD24-CD44+laryngeal cancer stem cel s. RESULTS AND CONCLUSION:Compared with CD24+CD44-cel s, CD24-CD44+cel s upregulated OCT4, SOX2, NANOG and TRAP1 expression levels (P<0.05). However, the expression of TRAP1 protein in human laryngeal squamous cel carcinoma was significantly decreased after RNA interference (P<0.05). The growth rate of TRAP1 gene silenced human laryngeal squamous cel carcinoma was significantly reduced (P<0.05), the cel arrest was in the G0/G1 phase, the number of cel s in the S phase was decreased (P<0.05), and there was no significant change in the M phase. TRAP1 gene silencing significantly inhibited the proliferation of human laryngeal squamous cel carcinoma stem cel s (P<0.05). Compared to the non-transfected cel s, the TRAP1 gene silencing significantly reduced the clone formation ability of transfected human laryngeal squamous cel carcinoma stem cel s (P<0.05), and TRAP1 gene silenced-human laryngeal squamous cel carcinoma stem cel s were more easy to trigger apoptosis by upregulating BAD and BAX expression levels (P<0.05). Overal , our experimental results indicate that the specific interference of TRAP1 gene expression could inhibit the proliferation and promote apoptosis of human laryngeal squamous cel carcinoma stem cel s.

Objective Blocking the expression of Survivin with siRNA, and the effects of suppling the proliferation of PC-2 cell and inducing its apoptosis were investigated. Methods Constructed the siRNA against Survivin plasmid expression vector and transfected it into PC-2 cell with lipofectamineTM 2000, the changes of Survivin expression were detected by semi-quantitive RT-PCR and immunohistochemical method, The effect of suppressing the proliferation of PC-2 cell was detected by the method of MTT; the effect of inducing PC-2 cell apoptosis was detected by flow cytometry. Results The sequence specific siRNA can effectively block the expression of Survivin both at themRNA and protein levels, the expression inhibition ratio was 81.25% at mRNA level and 74. 24% at protein level;blocking the expression of Survivin can suppress the proliferation of PC-2 cell significantly, 24, 48 hours after the cell was reseeded, the proliferation inhibition ratio was 28. 00% and 33. 38% respectively; 24, 48 hours after the transfection, 8.46 % and 7.53 % cells were induced to apoptosis respectively. Conclusion The siRNA against Survivin plasmid expression vector constructed in the study can blocking the expression of Survivin in PC-2 cell effectively and specifically; blocking the expression of Survivin can signiilcantly suppress the proliferation of PC-2 cell and induce a certain degree cells apoptosis; RNAi against Survivin is of a certain value in the gene therapy of pancreatic cancer.

To establish a HepG2 cell line ,which stably expressing CYP3A29 of Bama miniature pig in order to evaluate the drug metabolic characteristics of this isoenzyme,the gene for this system was obtained through total RNA extraction and RT-PCR assay.the gene was subcloned into plasmid PMD18-T,designated as pMD-CYP3A29.This gene was then amplified by PCR, and cloned into eukaryotic expression vector pcDNA3.1(+),and the recombinant plasmid was designated as pcDNA-CYP3A29. Sequencing was used to confirmed the correctness of the gene of this gene.the expressed gene was then transfected into HepG2 cells by lipid-media transfection and the transformants were screened by G418 for 10 generations ;the expression of CYP3A29 was identified by RT-PCR、West-blot and the metabolic activity of the transformant HepG2-CYP3A29 was verified by nifedipine oxidation.In comparison with HepG2, the transformant HepG2-CYP3A29 showed remarkable oxidative activity.It is apparent that the cell line stably expressing CYP3A29 isoenzyme was successfully established, and it may be used for the metabolic study of related drugs.

Objective To observe changes of erythropoietin (EPO) and rheology in moderate and severe obstructive sleep apnea hypopnea syndrome (OSAHS) patients after the noninvasive positive pressure ventilation (NPPV) treatment. Methods Healthy adults were selected as control group (n=40) while moderate to severe OSAHS patients were selected as OSAHS group. OSAHS group was underwent NPPV treatment then, Levels of sleep apnea hypopnea index (AHI), sleep mean minimum oxygen saturation (LSaO2) and serum erythropoietin (EPO) were assessed, routine blood test and hemodynam-ic indexes were also checked before treatment and 1 and 3 months after treatment in both groups. Results In both groups serum EPO, blood, blood rheology indexes, AHI, LSaO2 were analysised at each time point by ANOVA repeated measures, all of which show significant different between groups and between each time points within the same group. Indexes in OSAHS group improved with prolonged treatment , but they are in the normal range in the control. Conclusion OSAHS pa-tients with NPPV therapy can significantly relieve hypoxia, reduce serum EPO level and blood viscosity. So NPPV has impor-tant clinical significance in prevention and treatment of OSAHS.

Objective To study the microcirculation and structural changes, surviving area of expanded prefabricated flaps. Methods A total of 40 New Zealand rabbits were divided randomly into expanded prefabricated, expender lined, simple prefabricated and free flap groups, each consisting of 10 rabbits. For the expanded prefabricated, expender lined and simple prefabricated groups, after the femoral artery and vein were transplanted into subcutaneous tissues of abdomen, and expanders were implanted into the deeper dartos. The free flap group was a blank control group. For the expanded prefabricated group, the expansion was carried out on 7th day postoperatively. On postoperative day 52, when the expander was fully expanded, island flaps with the prefabricated vessels as the pedicles were formed. The flaps were measured by laser Doppler flowmetry, light microscopy and digital re-cording of survival arca. Results When compared with the other groups, the perfusion volume of mi-crocirculation enhanced, flaps survival improved (97.54±2.73) %, blood capillary were stronger, to-gether with microscopic changes were significant in the expanded prefabricated groups (P<0.05). Conclusion Expandedprefabricated flaps can increase the survival size of the flaps and the safety of flap transplantation.

Objective To evaluate the influence of head anteflexion on airway sealing pressure during intermittent positive pressure ventilation(IPPV) with ProSeal laryngeal mask airway (PLMA) with an esophageal vent.Methods Fifty ASA Ⅰ or Ⅱ patients (20 males and 30 females), aged 18-51 ye are, weighing 50-70 kg and scheduled for elective plastic surgery under general anesthesia, were enrolled in this study. Anesthesia was induced with fentanyl 2 μg/kg, propofol 2 μg/kg and vecuromium 0.1 mg/kg. PLMA with an esophageal vent was inserted at 2 min after intravenous vecuronium injection.The airway sealing pressure, the anatomic position of the cuff and the efficacy of positive pressure ventilation were checked in the neutral and anteflexed head positions with the cuff deflated and inflated to an intracuff pressure of 60 cm H2 O, respectively.Results The lungs were better ventilated in the head anteflexion position than in the head neutral position whether the cuff was deflated or inflated. There was no significant difference in the volume of air required to achieve an intracuff pressure of 60 cm H2O between the two head positions ( P＞ 0.05). The airway seating pressure increased from (27 ± 6) cm H2O in the head neutral position to (33 ± 6) cm H2O in the head anteflexion position, with no significant difference between them ( P＞ 0.05). The expired tidal volume and the peak inspiratory pressure during IPPV were (496 ± 81 ) ml and (14.3 ± 1.9) cm H2O respectively in the head neutral position and (496 ± 81 ) ml and ( 14.5 ± 2.1 )cm H2O respectively in the head anteflexion position.Conclusion Head anteflexion can significantly improve airway sealing but does not affect the anatomic position of the cuff.Appropriate head anteflexion is a simple and effective way to improve IPPV when the airway sealing pressure is inadequate in the head neutral position.

Objective To investigate the effect of lysyl oxidase (LOX) gene expression on proliferation, invasion and radiotherapy sensitivity in laryngeal cancer Hep-2 cells. Methods Hep-2 cells were divided into control group (normal cultured), negative control group (transfection reagent) and transfection group (LOX siRNA transfected). The expressions of LOX, Ki-67, PCNA, MMP-2 and MMP-9 mRNA were detected by real time-PCR and Western blot methods. The cell sur-vival rate and apoptosis irradiated by different doses of X-rays (0, 3, 6, 9, 12, 15 and 18 Gy) were detected by MTT and flow cytometry (FCM). Results The expression levels of LOX, Ki-67, PCNA, MMP-2 and MMP-9 protein and mRNA were sig-nificantly lower in Hep-2 cells after transfection than those of control group and negative control group (P<0.05). The cell survival rate was significantly inhibited 24 hours after irradiation (12, 15 and 18 Gy) in a dose-dependent manner (P<0.05). The apoptotic rate of transfection cells combined with radiotherapy was significantly higher than that of control and the nega-tive control groups (%:79.11 ± 1.26 vs 5.01 ± 1.02, 4.95 ± 1.12, 43.21 ± 2.1,P<0.05). Conclusion The expression of LOX can be down-regulated after LOX siRNA transfection, inhibiting proliferation and enhancing radiosensitivity, which may be related to the down-regulation of Ki-67, PCNA, MMP-2 and MMP-9 protein expression.

Aim To investigate the anti-arrhythmic effect and mechanism of ?-opioid receptor during myocardial ischemia and reperfusion in rats,and to initially determine the regulation of U50488H(U50,a selective ?-opioid receptor agonist) to angiotensinⅡ(AngⅡ),endothelin(ET) and nitric oxide(NO) in rats.Methods Rats were randomly divided into 7 groups,i.e.,control group,ischemia/reperfusion group(I/R),U50488H+I/R group,PTX group(PTX,a Gi/o proteininhibitor),Glib group(glibenclamide,a K_(ATP) channel blocker),Che group(chelerythrine,a selective PKC inhibitor),and Gen group(Genistein,a Tyrosine kinase inhibitor) respectively.The arrhythmia occurrence and score in different groups were observed and counted.The contents of AngⅡ,ET and NO in plasma of rats were also examined.Results ① Compared with I/R group,the arrhythmia score of U50+I/R group was significantly decreased.The effect of pared with I/R group,the arrhythmia score of U50+I/R group was significantly decreased.The effect of glibenclamide and chelerythrine respectively,the anti-arrhythmic effects induced by U50488H in the rats during myocardial ischemia and reperfusion were significantly attenuated or even completely blocked.③ The anti-arrhythmic effects of U50488H were not significantly affected by pretreatment with genistein.④ In comparison with normal rats,the contents of AngⅡand ET in plasma of I/R group were significantly increased,but the content of NO was decreased.With the administration of U50488H,the contents of AngⅡand ET in plasma of rats in U50488H+I/R group were significantly decreased.Meantime the content of NO was increased.Conclusions ① U50488H-induced anti-arrhythmic effects in the rats with myocardial ischemia and reperfusion are mediated by ?-opioid receptor.The signaling pathway may be related with(Gi/o,) PKC,and K_(ATP) channel.② The activation of ?-opioid receptor may elicit anti-arrhythmic effect through the down-regulations of AngⅡ or ET and up-regulation of NO in plasma of rats.

BACKGROUND: Tumor necrosis factor-associated protein 1 (TRAP1) is a heat-shock protein 90-related mitochondrial chaperone. Accumulative evidence has demonstrated that TRAP1 overexpression is closely related to carcinogenesis. However, the exact function and mechanism of TRAP1 in the occurrence of laryngeal carcinoma remains unclear. OBJECTIVE: To investigate whether RNA interference can inhibit TRAP1 overexpression and to explore its effects on growth and apoptosis of CD133+CD44+ laryngeal carcinoma stem cells. METHODS: CD133+CD44+ laryngeal carcinoma stem cells were sorted from human laryngeal carcinoma Hep-2 cellsusing immunomagnetic beads. The shRNA sequence of TRAP1 was designed and synthesized and CD133+CD44+ laryngeal carcinoma stem cells were transfected with LipofectamineTM 2000. Cell counting kit-8 assay, colony formation assay and flow cytometry were used to investigate the effects of interference of TRAP1 expression on growth and apoptosis of CD133+CD44+ laryngeal carcinoma stem cells. Spectrophotometric method was used to detect the activity of caspase-3, -8 and -9. RESULTS AND CONCLUSION: TRAP1 mRNA and protein expression levels were significantly decreased in TRAP1 shRNA-transfected CD133+CD44+ laryngeal carcinoma stem cells (P < 0.01). Compared with the blank control and negative control groups, the growth and colony formation of CD133+CD44+ laryngeal carcinoma stem cells were significantly inhibited in the TRAP1 shRNA-transfected group (P < 0.05). Apoptosis of CD133+CD44+ laryngeal carcinoma stem cells was significantly inhibited in the TRAP1 shRNA-transfected group as compared with the blank control and negative control groups (P < 0.05). TRAP1 shRNA-mediated cell apoptosis was associated with the activation of caspase-3, -8 and -9. These results suggest that RNA interference targeting inhibition of TRAP1 suppresses cell growth but promotes apoptosis in CD133+CD44+ aryngeal carcinoma stem cells. TRAP1 is likely to be a gene target for treatment of laryngeal carcinoma.