AIM: To observe the expression of hypoxia inducible factor-1? (HIF-1?) gene and heme oxygenase-1 (HO-1) gene in pulmonary arteries in hypoxic rats. METHODS: Forty male Wistar rats were exposed to hypoxia for 0, 3, 7, 14 or 21 days. Mean pulmonary pressure (mPAP), vessel morphometry, right ventricle hypertrophy index (RVHI) were measured. Lungs were either inflation fixed for immunohistochemistry and in situ hybridization or frozen for later measurement of HO-1 enzyme activity. RESULTS: During hypoxia, mPAP increased to significantly higher values than the control values after 7-day of hypoxia,reaching its peak after 14-day of hypoxia, then remained on the high level. Pulmonary artery remodeling developed significantly after 14-day of hypoxia. Expression of HIF-1? protein in control was poorly positive, but was up-regulated in pulmonary arterial tunica intimae of all hypoxic rats. In pulmonary arterial tunica media, the levels of HIF-1? protein were markedly up-regulated after 3-day and 7-day of hypoxia, then tended to decline after 14-day and 21-day of hypoxia. HIF-1? mRNA staining was poorly positive in control, hypoxia for 3 days and hypoxia for 7 days, but began to enhance significantly after 14-day of hypoxia, then remained stable. Expression of HO-1 protein began to increase after 7-day of hypoxia, reaching its peak after 14-day of hypoxia, then remained stable. Expression of HO-1 mRNA began to increase after 3-day of hypoxia, reaching its peak after 7-day of hypoxia, then declined. CONCLUSION: HIF-1? and HO-1 are both involved in the pathogenesis of hypoxia-induced pulmonary hypertension in rats. Furthermore, HIF-1? may inter-regulate with HO-1 gene in this process.

As one of the main members of the Rho GDI dissociation inhibitory factors,D4-GDI inhibits the dissociation of Rho protein and GDP,which is also involved in a wide range of celluar functions,such as cell contraction,adhesion,migration,proliferation and apoptosis.Recently,accumulating evidence has been suggested that D4-GDI is involved in the pathogenesis of several pulmonary diseases,such as lung cancer.Intervention of D4-GDI expression may improve the pathological changes and prognosis of these diseases.

Objective To observe the effect of PDK ( phosphoinositol -3-kinase, PI3K)/Akt-Nrf2 (Nuclear factor -E2 related factor) signal pathway on γ-glutamylcysteine synthetase (γ-GCS) in the bronchial epithelial cells of rats treated with cigarette smoke extract (CSE). Methods The bronchial epithelial cells were dealt with 10% concentration of CSE for different time and pretreated with PI3k inhibitor (LY294002). The expressions of Nrf2,p-Akt and γ-GCS proteins were examined by immunocytochemistry, flow cytometry, immunofluorescence and western blot. The expressions of γ-GCS mRNA were detected by reverse transcription-polymerase chain reaction (RT-PCR). Reduced glutathione(GSH) content and the lev-el of γ-CCS activi-ty were examined. Results GSH content in CSElh group was significantly decreased, but still higher in CSE3 and 6 groups compared to the control. Nrf2 protein mainly located in the cytoplasm. Nrf2 plasmosin mainly increased in the nucleus in control group, and Nrf2 nucleic protein significantly enhanced in CSE1, 3 and 6 groups. P-Akt protein was up-regulated at lh, reached its peak at 3h, declined slightly at 6h after exposure to CSE. The tendency of the percentage of p-Akt positive cells was as same as p-Akt protein. γ-GCS mRNA, protein and activity, gradually increased in CSE lh, CSE 3h,CSE 6h groups. Pretreated with LY294002, the expression of p-Akt protein was markedly decreases, while Nrf2 plasmosin expressed strongly, and γ-GCS mRNA, protein, activity and GSH content were significantly decreased compared to CSE3h group. Linear correlation analysis demonstrated that there were a positive correlation among Nrf2 and γ-GCS,γ-GCS activity, and among p-Akt and Nrf2,GSH,γ-GCS,γ-GCS activity. Conclusion P13K/Akt signal path might participate in Nrf2 nuclear translocation via regulating the expression of γ-GCS.

AIM: To investigate atypical protein kinase C(aPKC), extracellular signal regulated kinnase (ERK) regulating NF-E2-related factor 2 (NRF2)-?-gutamylcysteine synthetase (?-GCS) and the effect on lung of rats with chronic obstructive pulmonary disease (COPD). METHODS: The rat COPD model was established by intratracheal instillation of lipopolysaccharide twice and exposure to cigarette smoke daily. The ?-GCS activity was measured. The expression of ?-GCS mRNA in lung tissue was examined by in situ hybridization (ISH) and reverse transcription-polymerase chain reaction (RT-PCR). The protein expressions of p-aPKC?/?, p-ERK, NRF2 and ?-GCS in lung tissue were detected by immunohistochemistry (IH) and Western blotting, respectively. RESULTS: (1) The ?-GCS activity was higher in COPD group than that in control group. (2) The expression of ?-GCS mRNA in the COPD group was stronger than that in control group. ISH showed that the ?-GCS mRNA was expressed in alveolar epithelium and bronchiolar smooth muscle cell in the COPD group. (3) The protein expressions of p-aPKC, p-ERK, NRF2, ?-GCS were significantly higher than those in control group. IH showed that p-aPKC, p-ERK, NRF2, ?-GCS proteins were expressed in alveolar and bronchiolar epithelium in the COPD group. (4) There was a positive correlation between NRF2 and ?-GCS. ?-GCS mRNA, p-aPKC?/?, p-ERK were also positively correlated with NRF2. CONCLUSION: By upregulating the signal transduction of NRF2-?-GCS, the ERK and aPKC?/? may play an important role in the mechanism of COPD formation.

AIM: To investigate Nrf2 that regulates the expression of ?-glutamylcysteine synthetase(?-GCS) in the inflammatory cells in bronchial asthma guinea pig bronchoalveolar lavage fluid(BALF).METHODS: Adult male guinea pigs were randomly divided into control group(group A),asthmatic group(group B) and dexamethasone group(group C).Asthmatic model was established by the method of ovalbumin challenge.MDA concentration in the lung tissue homogenate was detected.The total cell count and the proportion of inflammatory cells in BALF were measured.The methods of immunohistochemistry and in situ hybridization were used for detection of the protein and mRNA expressions of Nrf2,Bach1 and ?-GCS.RESULTS:(1) The proportion of eosinophils(EOS) in BALF and the MDA concentration of the lung tissue in group B were higher than those in group A and group C.(2) The result of in situ hybridization indicated that the A value of ?-GCS was the highest in group A compared to group B and group C,but the A value of Nrf2 and Bach1 in 3 groups has no statistical significance.(3) Immunohistochemistry indicated that the A value of ?-GCS in group B was lower than that in group A.The positive rate in cell nucleus of Nrf2 in group B was lower than that in group A and group C.The positive rate in cell nucleus of Bach1 in group B was higher than that in group A and group C.(4) The mRNA expression of ?-GCS(A value) showed positive correlation with the positive rate in cell nucleus of Nrf2 and negative correlation with the positive rate in cell nucleus.A negative correlation between the proportion of EOS in BALF of group B and the ?-GCS mRNA was observed.CONCLUSION: There is disequilibrium between oxidation and anti-oxidation in bronchial asthma guinea pig.Inflammatory reaction decreases the expression of ?-GCS in the inflammatory cells in bronchial asthma guinea pig.Dexamethasone regulates the nuclear translocation of Nrf2/Bach1 and increases the expression of ?-GCS.

A model of chronic hypoxic pulmonary hypertension (HPH) was reconstructed in rats exposed to hypoxia with normal pressure for 14 d. Chronic HPH was prevented by giving Ligustrazine (LTZ) in an intraperitoneal dose of 80 mg ?kg-1 wt. twice daily. The mean pulmonary arterial pressure (mPAP), plasma and pulmonary small arterial cGMP level, and mRNA expression of nitric oxide synthase (NOS) gene in lung tissues were studied. The results showed that the mPAP was significantly higher, but plasma and pulmonary small arterial cGMP level as well as mRNA expression of NOS gene in lung tissues were markedly lower in chronic hypoxic rats than those in control animals. LTZcould reverse those changes of above indexes in hypoxic rats, but did not affect those indexes in normal rats. There was a strong negative correlation between cGMP level and mPAP. It is suggested that the lower mRNA expression of NOS gene in hypoxic rats may be one of pathogenetic mechanisms in chronic HPH, and LTZ can increase the mRNA exprssion of NOS gene and the production of nitric oxide in hypoxic rats, which may be an important mechanism in LTZ preventing chronic HPH.

Objective To investigate the effects and mechanisms of adrenomedullin(ADM)synthesized in alveolar macrophages in patients with chronic obstructive pulmonary disease.Methods The bronchoalveolar lavagae fluids(BALF)were collected by bronchoscopy in 15 cases of COPD and 14 healthy cases.The expression of ADM in plasma,BALF and the culture supernatants of alveolar macrophages(AMs)were analysed by radioimmunoassay.Results (1)The cells,PMNs and AMs in BALF of COPD group were significantly higher than those of healthy group(P

Objective To investigate the biological effect of transforming growth factor-?1(TGF-?1) on inducing myofibroblast formation in hypoxic pulmonary vascular remodeling.Methods Forty male Wistar rats were exposed to hypoxia for 0,3,7,14 or 21 days.Mean pulmonary arterial pressure(mPAP),vessel morphometry,right ventricle hypertrophy index(RVHI) were measured.Immunocytochemistry was used to measure the expression of ?-Smooth-muscle actin(?-SMA) and TGF-?1 in pulmonary artery walls and in situ hybridization was used to measure the expression of TGF-?1 mRNA in pulmonary artery walls.Ultrastructure alveolar wall vessels were observed by electron microscopy.Human embryonic lung fibroblasts(KMB17) phenotype after induction of hypoxiaand TGF-?1 were recorded through cell culture.Results(1) mPAP increased significantly after 7-day of hypoxia(P

Objective To investigate the clinical efficacy of paraspinal muscle gap approach in the short segment internal fixation of thoracolumbar fractures.Methods Forty-five patients with thoraco-lumbar fractures but without spinal decompression underwent posterior short segment internal fixation,in-cluding 20 cases via paraspinal muscle gap approach(group A)and 25 cases via traditional posterior mid-line approach.Operative time,intraoperative blood loss,postoperative drainage,visual analogue scale (VAS)score,correction rate of Cobb angle and correction rate of vertebral collapse were recorded and the surgical results were compared between the groups.Results All patients got bony union without internal fixation loosening,broken nails or broken rods.There were significant differences in operative time [(88 ± 17)min vs(105 ±14)min],blood loss [(121 ±24)ml vs(230 ±31 )ml]and postoperative drainage [(66 ±28)ml vs(250 ±45)ml]between group A and B respectively(P<0.05).The differences in cor-rection rate of the Cobb angle [(82.3 ±1.58)% vs(83.5 ±3.71)%],correction rate of the vertebral collapse [(88.22 ±3.18)%vs(87.19 ±2.16)%]and postoperative VAS score were not significant be-tween group A and B respectively(P>0.05 ).Conclusion Internal fixation via paraspinal muscle gap approach has the advantages of less trauma,simple approach,short operative time,less blood loss,quick recovery after surgery.It is consistent with the modern concept of minimal invasion and worthy of sprea-ding.

Objective To explore the effect of nicotine on rats callus content and maturity in the process of fracture healing.Methods Sixty male Sprague-Dawley rats were randomly divided into model group,mild nicotine group and severe nicotine group (n =20/each group).The 3-mm bone defects fracture models were made in the junction of the lower 1/3 of the rat left radial.Five rats of each group were sacrificed randomly in the 3,7,14,21 days after surgery,respectively.The left radial were collected as the observed object.The callus thickness and maturity of the specimens were detected by HE staining.Results At the 3rd days after modeling,the difference in specimens callus thickness between each treatment group and the model group was not statistically significant (P ＞ 0.05),no difference in the maturity of the callus under the microscope; callus thickness in mild and severe nicotine groups and model group was (1.59 ± 0.09) mm,(1.43 ± 0.12) mm,(1.39 ± 0.09) mm at the 7th day after modeling,(1.98 ± 0.12) mm,(1.78 ± 0.08)mm and (1.68 ± 0.09) mm at the 14th day after modeling,and (2.39 ± 0.09) mm,(1.93 ± 0.11) mm,(1.89 ± 0.09) mm at the 21 st day after modeling; The difference of callus thickness in specimens between each treatment group and the model group had statistical significance (P ＜ 0.05,P ＜0.01),callus thickness and maturity of the treatment group were lower than that in the model group.Conclusions Nicotine affects the proliferation and differentiation of callus,reduces callus formation,inhibits maturity transformation of bone,and delays the healing process of fracture.