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AIM:To study the expression of matrix metalloproteinase-9(MMP-9),matrix metalloproteinase-2(MMP-2) and the tissue inhibitor of metalloproteinase(TIMP-1) in the lung tissue of the hypercapnia rat.METHODS:Forty Wistar rats were randomly divided into a control group (group A,n=20) and hypercapnia group (group B,n=20). Group B received mix gas exposure (6% CO_2,21% O_2,72% N_2) 7 h daily for 4 weeks. The parameters we would examine were as follow:arterial blood gas;the mean pulmonary artery pressure;MMP-2,MMP-9,TIMP-1,and NE activity in lung tissue. Masson pigmentation of elasticity fibre was analyzed by computer image analyzer. Histopathological changes of lung tissue were observed under light microscope. The protein expression of MMP (MMP-2,MMP-9) and TIMP (TIMP-1) in lung tissue were determined by immunocytochemistry.RESULTS:Decompensate respiratory acidosis (pH=7.20±0.04,PaCO_2=7.84±0.15) developed in group B. The mean pulmonary artery pressure were similar between groups B and A (P>0.05). Tissue edema in the lung,endothelial cell damage of the small blood vessels,pulmonary micro thrombus formations and increased pulmonary capillary permeability were observed in group B. NE activity increased significantly (P<0.01). However,no significant change of MMP-2,MMP-9,TIMP-1 activity was found in group B and group A (P>0.05). There was significant decrease in the relative content of elasticity fibre in lung tissue in group B compared to group A (P<0.01). The expression of MMP-2 protein in the lung tissue of group B was lower than that in group A (P<0.01),but the expression of both MMP-9 and TIMP-1 proteins in the lung tissue in group B were higher than those in group A (P<0.01).CONCLUSION:Hypercapnia rat model is successfully reproduced by exposure of animals to the mix gas exposure (6% CO_2,21% O_2,and 72% N_2). The pulmonary artery pressure is not affected by hypercapnia. High concentration of CO_2 causes increase of NE activity and decrease in the relative content of elasticity fibre. High concentration of CO_2 causes the increase of MMP-2 protein expression and decrease in the MMP-9 and TIMP-1 protein expression.
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Objective To evaluate the efficacy and safety of long-term anticoagulation therapy with warfarin in elderly patients with pulmonary thromboembolism (PTE) and the maintenance dosage of warfarin,and provide evidence for anticoagulation therapy. Methods Twenty elderly patients ( ≥65 years old) with PTE whose anticoagulation therapy duration exceeded 12 months were included into this study. The hemorrhage event, recurrence event and the maintenance dosage of warfarin in each patient were determined by the follow-up record. Results Six male patients and 14 female patients [(73.55 ± 5.76) years old] were diagnosed as PTE by CT pulmonary arteriography(CTPA). The average duration of follow-up was (22.60 ± 11.45 ) months. No fatal hemorrhage event such as cerebral hemorrhage was found during the course of long term anticoagulation therapy, and mild hemorrhage was found in 5 patients, including 1 patient with gingiva hemorrhage, 1 patient with epistaxis, 1 patient with hemoptysis, 1 patient with ecchymosis in the left leg and 1 patient with conjunctiva hemorrhage. PTE recurrence emerged in 1 patient and the recurrence rate was 5%.No change was found in the maintenance dosage of warfarin during the course of long-term anticoagulation therapy and the average dosage of warfarin was about 3.5 mg with sufficient anticoagulation therapy.Conclusions Long-term anticoagulation therapy with warfarin in elderly patients with PTE is safe and efficacious. The maintenance dosage of warfarin is about 3.5 mg, and detecting the international normalized ratio regularly is necessary.
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Objective To pool the data of studies about bosentan therapy in pulmonary hypertension (PAH) and evaluate the efficacy and safety of bosentan therapy. Methods A search was performed in PubMed (from 01/01/1968 to 01/05/2006), Embase (from 01/01/1980 to 01/05/2006) and China National Knowledge Infrastructure (CNKI) (from 01/ 01/ 1978 to 01/ 05/ 2006) to identify relevant articles. Randomized-Controlled Trials (RCT) about the efficacy and safety of bosentan therapy in PAH patients were included to evaluate the short-term and long-term efficacy and safety of bosentan therapy in a method of Meta-analysis. Results (1)Two RCT studies including 243 PAH patients were chosen to evaluate the short-term efficacy and safety of bosentan therapy. Compared with placebo treatment, bosentan therapy could improve exercise capacity of PAH patients:① Distance covered in a 6-minute walk test increased 47.71 meters (95% CI:26.09 to 69.33, P
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AIM: To investigate the effect of ambroxol on pulmonary and vascular injury in chronically hypoxic rats. METHODS: 36 male Wistar rats were randomly divided into 3 groups: normal control,chronically intermittent hypoxia(CIH) and ambroxol precaution group(AP).The CIH and AP groups were made into the chronically hypoxic models .The mean pulmonary artery pressure(PAPM) and the levels of plasma superoxide dismutase (SOD) and plasma nitric oxide (NO),lipid peroxide(LPO) were determined. The levels of the lung homogenates SOD, LPO, NO and the changes in pulmonary vascular structure were also examined. RESULTS: The levels of plasma and lung homogenates SOD,NO in CIH group were respectively significantly lower than that of normal control and AP group ( P