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 analyze the status of occupational hazards in key positions of the small and micro book and newspaper printing enterprises in Beijing City. Methods A total of 16 small and micro printing enterprises in Beijing City were selected as the research subjects using the judgment sampling method. The status of occupational hazard was assessed using on-site occupational health investigations. The volatile chemical components in organic solvents such as inks and cleaning agents used in the workplace, the level of chemical hazardous agents in the air, and noise intensity were detected and analyzed. Results A total of 1 105 workers from 16 small and micro printing enterprises were included. The occupational hazard exposure rate was 22.2% (245/1 105), with chemical hazardous agents and noise exposure rates of 13.5% and 22.2%, respectively. The rate of compliance with occupational health training among the head of the enterprise and the occupational health management personnel, the regular detection rate of occupational hazards in last year, and the rate for the occupational health examination in last year were both 100.0%. The rate for annual update of occupational hazard project reporting was 93.8% (15/16). The usage rates of gas mask and noise-proof earplug were 68.8% (11/16) and 50.0% (8/16), respectively. The effectiveness rates of anti-toxic and noise-reduction facilities were 87.5% (14/16) and 62.5% (10/16). The sign setting rates of chemical hazardous agents and noise warning were 93.8% (15/16). Acetone and isopropanol were found in ink and cleaning agents in 15 printing enterprises, while toluene, xylene, and ethylbenzene were found in three, two, and one enterprise, respectively. Benzene, 1,2-dichloroethane, n-hexane, and trichloroethylene were not found in all 16 enterprises. Both the exposure concentration of short term and exposure concentration of time weighted average of the above chemical hazards were lower than the lower limit of quantitation of the detection method in the workplace and work site air among the 16 printing enterprises, and none of concentration was exceeded the national standard. A total of 240 noise work sites were detected, and the national noise-exceeding rate was 11.2%(27/240). Conclusion Noise hazards are prominent in the small and micro printing enterprises in Beijing City, and attention should be paid to the prevention and protection of noise-exposure. The usage rate of personal protective equipment is not high, and the training and on-site supervision management of protective equipment wearing in workers should be strengthened.

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.

Objective:To establish a method for the determination of eight N-nitrosamines (N-nitrosodimethylamine, N-nitrosodimethylamine, N-nitrosomethylmethylamine, N-nitrosodibutylamine, N-nitrosopropylamine, N-nitrosomorpholine, N-nitrosodianiline and N-nitrosopiperidine) in the air of workplace by gas chromatography-tandem mass spectrometry (GC-MS/MS) .Methods:From January to August 2023, eight N-nitrosamines in the air of workplace were collected by ThermoSorb/N column, eluted with 4 ml methanol-dichloromethane (1∶1 volume ratio), separated by VF-624 ms capillary column, detected by multiple reaction monitoring mode and quantified by external standard method. The detection limit and precision of the method were also analyzed.Results:The linear range of the method for the determination of eight N-nitrosamines was 1.0-20.0 μg/L, the correlation coefficient was 0.9993-0.9999, the detection limit was 0.051-0.132 μg/L, and the minimum quantitative concentration was 0.030-0.078 μg/m 3 (calculated by collecting 22.5 L of air sample and eluting with 4.0 ml stripping liquid). The within-run precisions were 2.05%-6.89% and the between-run precisions were 2.41%-8.26%. The desorption rates were 67.20%-102.60%. The sample can be kept at least 7 days at 4 ℃. Conclusion:GC-MS/MS method for the determination of eight N-nitrosamines in workplace air has high sensitivity and good precision, and can accurately determine the content of eight N-nitrosamines in workplace air.

Objective:To establish a method for the determination of eight N-nitrosamines (N-nitrosodimethylamine, N-nitrosodimethylamine, N-nitrosomethylmethylamine, N-nitrosodibutylamine, N-nitrosopropylamine, N-nitrosomorpholine, N-nitrosodianiline and N-nitrosopiperidine) in the air of workplace by gas chromatography-tandem mass spectrometry (GC-MS/MS) .Methods:From January to August 2023, eight N-nitrosamines in the air of workplace were collected by ThermoSorb/N column, eluted with 4 ml methanol-dichloromethane (1∶1 volume ratio), separated by VF-624 ms capillary column, detected by multiple reaction monitoring mode and quantified by external standard method. The detection limit and precision of the method were also analyzed.Results:The linear range of the method for the determination of eight N-nitrosamines was 1.0-20.0 μg/L, the correlation coefficient was 0.9993-0.9999, the detection limit was 0.051-0.132 μg/L, and the minimum quantitative concentration was 0.030-0.078 μg/m 3 (calculated by collecting 22.5 L of air sample and eluting with 4.0 ml stripping liquid). The within-run precisions were 2.05%-6.89% and the between-run precisions were 2.41%-8.26%. The desorption rates were 67.20%-102.60%. The sample can be kept at least 7 days at 4 ℃. Conclusion:GC-MS/MS method for the determination of eight N-nitrosamines in workplace air has high sensitivity and good precision, and can accurately determine the content of eight N-nitrosamines in workplace air.

Objective:To construct a nomogram prediction model for 28-day mortality in septic shock patients based on routine laboratory data mining and verify its predictive value.Methods:The clinical data of patients with septic shock admitted to Anhui Medical University Affiliated Fuyang Hospital from January 2018 to November 2023 were retrospectively analyzed. The patients were randomly divided into training set and validation set according to the ratio of 8∶2. The patient's gender, age, body mass index, underlying disease, smoking history, alcohol history, infection site, acute physiology and chronic health evaluation Ⅱ (APACHEⅡ), sequential organ failure assessment (SOFA), respiratory rate, heart rate, mean arterial pressure, blood lactate, procalcitonin, C-reactive protein, white blood cell count, platelet count, serum alanine aminotransferase, aspartate aminotransferase, urea nitrogen, serum creatinine, fibrinogen, D-dimer, albumin on the first day of admission to the intensive care unit (ICU), duration of mechanical ventilation, and length of ICU stay were collected. The patients were divided into survival and death groups based on their 28-day prognosis. The factors influencing 28-day mortality were analyzed, and routine laboratory data were used to develop a nomogram model for predicting the risk of 28-day mortality in septic shock patients. The model was validated and assessed using the Bootstrap method, calibration curve, and receiver operator characteristic curve (ROC curve).Results:Finally, 128 patients with septic shock were enrolled, and 32 (31.07%) death within 28-day of 103 patients in the training set, 8 (32.00%) death within 28-day of 25 patients in the validation set. Logistic regression analysis showed that APACHEⅡ score [odds ratio ( OR) = 5.254, 95% confidence interval (95% CI) was 2.161-12.769], SOFA score ( OR = 4.909, 95% CI was 2.020-11.930), blood lactate ( OR = 4.419, 95% CI was 1.818-10.741), procalcitonin ( OR = 4.358, 95% CI was 1.793-10.591) were significant factors influencing 28-day mortality in septic shock patients (all P < 0.01). Taking the above influencing factors as predictors, a nomogram model was established, with a total score of 89-374, corresponding to a mortality risk of 0.07-0.89. The results of nomogram model validation showed that the C-index was 0.801 (95% CI was 0.759-0.832), and the correction curve for predicting 28-day mortality in patients with septic shock was close to the ideal curve, Hosmer-Lemeshow test showed that χ 2 = 0.263, P = 0.512. The results of the ROC curve of the training set showed that the nomogram model had a sensitivity of 78.13% (95% CI was 59.57%-90.06%), a specificity of 80.28% (95% CI was 68.80%-88.43%) and area under the curve (AUC) of 0.854 (95% CI was 0.776-0.937) in predicting 28-day mortality in patients with septic shock. The results of the validation set ROC curve showed that the nomogram model had a sensitivity of 75.00% (95% CI was 35.58%-95.55%), a specificity of 88.23% (95% CI was 62.25%-97.94%) and AUC of 0.871 (95% CI was 0.793-0.946) in predicting 28-day mortality in patients with septic shock. Conclusion:A nomogram prediction model constructed based on routine laboratory data mining can effectively predict 28-day mortality in septic shock patients, and its prediction performance is good.

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.