Objective　To study the probability of using hepatitis D virus (HDV) ribozyme as a kind of anti-hepatitis-C-virus (HCV) gene thera-py drugs. Methods　The natural HDV genomic ribozyme′s stem Ⅳ was optimized and its substrate-binding region reconstructed, thus three recombinant HCV-specific HDV genomic ribozymes RzC1, RzC2 and RzC3 were obtained. HCV RNA 5'-noncoding region and 5'-fragment of C region (HCV RNA5'-NCR-C) were transcribed from plasmid pHCV-neo by T7 phage RNA polymerase in vitro, and radiolabelled at its 5'-end. The trans-cleaving reaction was performed by mixing the ribozymes and substrate at mol ratio 100∶1 under conditions as follows: 37℃, pH7.5, Mg2+ 20 mmol/L and deionized formamide 2.5 mol/L. Percentage of trans-cleaved products were calculated at different time points and used as the activity indicator of the three ribozymes. Results　RzC1, RzC2 trans-cleaved more substrate when the time extended, and got to 24.9%,20.3% after reac-ting for 90 minutes respectively; RzC3 was not able to trans-cleave its substrate. Conclusion　Recombinant HDV genomic ribozymes have the ability to trans-cleave HCV RNA, but the appropriate target sequence should be selected.

Objective:To evaluate the efficacy and related factors of high-flow nasal cannula (HFNC) for the treatment of adult typeⅠ respiratory failure.Methods:The medical records of the subjects with acute hypoxemic respiratory failure supported by HFNC therapy in the medical intensive care unit between October 2017 and February 2019 were reviewed retrospectively. The patients′ baseline characteristics and the serial changes in the respiratory parameters after HFNC therapy at 1 and 24 hours were measured. Therapy success was defined as the avoidance of intubation. The subjects were divided into two groups.Results:Of the 75 eligible patients, 62.7%(47/75) belonged to success group. Overall, HFNC therapy significantly improved the physiologic parameters, such as partial pressure of arterial oxygen (PaO 2), saturation of arterial oxygen (SaO 2), respiratory rate (RR), and heart rate (HR), throughout the first 24 hours. After the adjustment for the other clinical variables, acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ), sequential organ failure assessment (SOFA), cardiogenic pulmonary edema, and PaO 2 improvement at 1 and 24 hours were associated with therapy success. The overall intensive mortality was 25.3%. However, out of 37.3% of the patients who required belonged to failure group, the mortality was 67.9%. The mortality in the failure group was associated with the use of a vasopressor and a limited PaO 2 improvement at 1 hour. Conclusions:HFNC can significantly improve the physiological parameters of adult patients with acute type I respiratory failure and avoid endotracheal intubation in some patients. The failure to improve oxygenation within 24 hours was a useful predictor of intubation. Among the failure group, the vasopressor use and failed oxygenation improvement were associated with mortality.

ObjectiveTo investigate the role of the Wnt1/β-catenin signaling pathway in the intervention of medicated serum of Buyang Huanwutang （BYHWT） in endothelial-to-mesenchymal transition （EndMT） of human pulmonary artery endothelial cells （HPAECs） as well as its related mechanisms. MethodMedicated serum of BYHWT was prepared by gavage to New Zealand rabbits with a dosage of 53.36 g·kg^-1·d^-1 after decocting the medicine as usual. In addition， the same volume of normal saline was used to prepare blank serum. The HPAECs were cultured in vitro， and then induced by the transforming growth factor-β₁ （TGF-β₁） to establish the EndMT model. Five groups were established： blank group （10% blank serum）， model group （TGF-β₁+10% blank serum）， low-dose BYHWT group （TGF-β₁+2.5% medicated serum+7.5% blank serum）， medium-dose BYHWT group （TGF-β₁+5% medicated serum+5% blank serum） and high-dose BYHWT group （TGF-β₁+10% medicated serum）. Through Western blot， the expressions of Wnt1， β-catenin， and glycogen synthase kinase-3β （GSK-3β） were detected. In order to further clarify the mechanism of the Wnt1/β-catenin signaling pathway in the intervention of the medicated serum of BYHWT in inhibiting EndMT， the overexpression of β-catenin was confirmed by polymerase chain reaction after plasmid of overexpression β-catenin was constructed and transfected into the HPAECs. The HPAECs were intervened by 10% medicated serum with the optimal effect in previous studies. Then， they were divided into another five groups： the blank group （10% blank serum）， the model group （TGF-β₁+10% blank serum）， the BYHWT group （TGF-β₁+10% medicated serum）， the BYHWT+overexpression plasmid control group （TGF-β₁+10% medicated serum+blank plasmid） and the BYHWT+β-catenin overexpression plasmid group （TGF-β₁+10% medicated serum+β-catenin）. Apart from that， cell proliferation ability was detected by the methyl thiazolyl tetrazolium （MTT） method and cell migration ability by scratch assay and Transwell assay together. Immunofluorescence was adopted to detect the expressions of platelet endothelial cell adhesion molecule （PECAM-1/CD31）， vascular endothelial cadherin （VE-cadherin）， fibroblast-specific protein 1 （FSP1）， and α-smooth muscle actin （α-SMA）. ResultIn comparison to the blank group， the expressions of Wnt1 and β-catenin were significantly increased （P<0.01） while the expression of GSK-3β significantly decreased （P<0.01） in the model group. In comparison to the model group， the expressions of Wnt1 and β-catenin were significantly decreased （P<0.01） while the expression of GSK-3β was significantly increased （P<0.01） in the high-dose BYHWT group. The expression of β-catenin was significantly decreased （P<0.01） while the expression of GSK-3β was significantly increased （P<0.01） in the medium-dose BYHWT group. There was no significant difference in these indexes of the low-dose BYHWT group. In comparison to the blank group， proliferation and migration abilities were remarkably increased （P<0.01） and the immunofluorescence intensities of CD31 and VE-cadherin were decreased， while those of FSP1 and α-SMA were increased in the model group. In comparison to the model group， proliferation and migration abilities were significantly decreased （P<0.01） and the immunofluorescence intensities of CD31 and VE-cadherin were increased， while those of FSP1 and α-SMA diminished in the BYHWT group. Beyond that， the change trend of those indexes in the BYHWT+β-catenin overexpression plasmid group was consistent with that in the model group. In comparison to the BYHWT+overexpression plasmid control group， proliferation and migration abilities were significantly increased （P<0.01） and the immunofluorescence intensities of CD31 and VE-cadherin were decreased， while those of FSP1 and α-SMA were increased in the BYHWT+β-catenin overexpression plasmid group. ConclusionMedicated serum of BYHWT can inhibit EndMT of HPAECs by the Wnt1/β-catenin signaling pathway.