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Objective To investigate the mechanism of baicalin in improving pathological airway mucus by regulating the expression of airway epithelial mucus regulators mucin 5AC (MUC5AC) and cystic fibrosis transmembrane conductance regulator (CFTR) through nuclear factor κB (NF-κB) signaling pathway. Methods MTT assay was used to detect the effects of different concentrations of baicalin on the viability of human lung cancer H292 cells in order to determine the proper dose of baicalin for subsequent experiments. After H292 cells were induced by IL-1β to establish in vitro inflammatory cell model of mucus hypersecretion, the cells were divided into blank control group, model group, NF-κB inhibitor group (PDTC group, 100 μmol/L) and baicalin group (200 μg/mL). After 24 h of drug intervention, the contents of MUC5AC, IL-8, and TNF-α in the culture supernatant and the levels of MUC5AC and CFTR in the cytoplasm of each group were detected by ELISA. Real-time fluorescent quantitative PCR was adopted to detect the mRNA expression of MUC5AC and CFTR. Western blotting was performed to test the expression of p65 and IκB (inhibitor of NF-κB). Results The results of MTT assay showed that 200 μg/mL was a safe concentration of baicalin for subsequent experiments, with cell viability larger than 80%. As compared with the blank control group, the protein expression of MUC5AC, IL-8, TNF-α, p65 and the mRNA level of MUC5AC in culture supernatant and cytoplasm were all significantly increased in the model group (P < 0.05), while the expression of IκB and CFTR proteins as well as the CFTR mRNA level were remarkably decreased (P < 0.05). When compared with the model group, the PDTC group presented lower level of MUC5AC secretion, declined protein levels of IL-8, TNF-α and p65, as well as MUC5AC mRNA in the culture supernatant (P < 0.05), while higher protein expression of MUC5AC, CFTR and IκB in the cytoplasm, along with elevated mRNA level of CFTR (P < 0.05). In terms of the baicalin group, the secretion levels of MUC5AC, IL-8 and TNF-α were greatly diminished in culture supernatant (P < 0.01) as compared with the model group, whereas the expression of IκB as well as the protein and mRNA levels of CFTR notably improved (P < 0.01), and there was no significant difference in MUC5AC mRNA expression. Conclusion Baicalin reduces MUC5AC secretion and increases CFTR expression by inhibiting the activity of NF-κB, and thus attenuates airway inflammation.

In order to study the influence of long-term water action on the behavior characteristics of steel slag aggregate-asphalt interface and the related mechanism, atomic force microscope, X-ray diffraction, scanning electron microscope, immersion Marshall test, rutting test and so on were used to analyze from macro and micro perspectives. The results show that long-term water erosion changes the surface chemical properties of steel slag, making the surface roughness, surface area and adhesion strength of the steel slag increase. Compared with limestone asphalt mixture, the residual stability and dynamic stability of steel slag asphalt mixture have a growth potential, but the swelling of hot-sealed steel slag and cold-sealed steel slag is different. The swelling amount of cold-sealed steel slag asphalt mixture is greater than that of hot-sealed steel slag asphalt mixture, which should be treated differently in the application process. The slow digestion rate of f-CaO in cold-sealed steel slag aggregate causes the volume expansion of the specimen in the late stage, aggravates the generation of microcracks on the surface of the specimen, and results in the poor freeze-thaw splitting strength of cold-sealed steel slag asphalt mixture in the late stage. [ABSTRACT FROM AUTHOR]

AIM: This study aims to investigate the histopathological and ultrastructural alterations in the lung tissues of rats induced by a single intratracheal administration of bleomycin, with the objective of establishing a reliable model for future applications. METHODS: Six to eight-week-old SD rats were randomly allocated into two groups: the control group and the model group (n=12). Pulmonary fibrosis was induced in the rat models by a single intratracheal instillation of bleomycin (3 mg/kg), while an equivalent volume of saline was administered to the control group. The rats were executed on the 42nd day. Twelve rats remained in the control group, while nine rats remained in the model group. Lung tissue imaging was conducted using CT scans. Lung function tests were performed to assess changes in forced vital capacity (FVC) and dynamic lung compliance (Cdyn). Lung stiffness was determined through Young's modulus testing using a rheometer. The pathological structure of lung tissues was examined using both HE and Masson staining methods. Additionally, transmission electron microscopy was employed to evaluate collagen deposition in lung tissues, alveolar type II epithelial cells, macrophages, and ultrastructural changes of the respiratory membrane. RESULTS: CT scans revealed honeycomb patterns in the lungs of model rats, along with partial bronchiectasis/bronchiectasis. In comparison to the control group, the model group exhibited significantly lower FVC and Cdyn values, while lung stiffness were increased. HE and Masson staining demonstrated that rats in the model group exhibited alveolar structure destruction, alveolar septum thickening, inflammatory cell infiltration, and collagen deposition in alveolar septum. Transmission electron microscopy revealed several abnormalities in the model group: increased collagen fibers in the alveolar septa, misalignment of micro-villi in alveolar type II epithelial cells, wrinkled nuclei with increased heterochromatin, swollen cytoplasmic mitochondria, fractured or haphazardly structured mitochondrion cristaes, and a significant decrease in their number (P<0.05). Furthermore, lamellar bodies were vacuolated and reduced in number (P<0.05), and dilated endoplasmic reticulums with degranulation were observed. There was an increase in alveolar macrophages and interstitial macrophages (P<0.01). The respiratory membrane displayed structural disruptions and an increase in thickness (P<0.01). CONCLUSION: Bleomycin induces decreased lung compliance, alveolar epithelial injury, alveolar septum thickening, collagen deposition, and an increase in interstitial macrophages, ultimately resulting in pulmonary fibrosis in rats. [ABSTRACT FROM AUTHOR]

As one of the important sources of environmental pollution, the sound management of chemicals has entered the international agenda beyond 2020. This article presents the latest trends of sound management of chemicals in the international community, including the negotiation progress on the framework of Strategic Approach to International Chemicals Management (SAICM) and the sound management of chemicals and waste beyond 2020, relevant resolutions adopted by the Fifth United Nations Environment Conference, and preparations for the Science-Policy Panel to contribute further to the sound management of chemicals and waste and to prevent pollution, elabo- rates on the content of the framework text of SAICM beyond 2020 and analyzes the new changes and requirements of the international situation. The sound management of chemicals has become an important chapter in global environmental governance, and China is facing new international situations and challenges. As a new requirement of the Communist Party of China (CPC) Central Committee for deepening the battle against pollution, new pollutants control is the primary task of environmental risk management of toxic and harmful chemicals, which is highly consistent with the international goal of sound management of chemicals. At present, it is necessary to gather joint efforts from both domestic and international sources, actively respond to international challenges, and embark on a new journey in the domestic new pollutants control. [ABSTRACT FROM AUTHOR]

In order to evaluate the anti-reflective cracking performance of high viscosity and high elasticity asphalt mixture (HVHEAM) for ultra-thin wear layer, the improved overlay tester was used to study the effects of different gradation, asphalt content and filler-asphalt ratio on the anti-cracking performance of the HVHEAM. The results show that the anti-reflection crack performance of the dense skeleton type HVHEAM is much higher than those of AC-10 and SMA-10, and the excellent crack resistance of the HVHEAM is mainly reflected in the large initial tensile stress of cracks simultaneously, it has good crack resistance and attenuation performance. Increasing the asphalt contents can improve the anti-crack attenuation performance of the HVHEAM. Increasing the filler-asphalt ratio helps to increase the initial crack resistance of the HVHEAM, but it will reduce the crack-resistance attenuation performance of the mixture, and a good balance between strength and crack-resistance attenuation is achieved when the filler-asphalt ratio is in the range of 0. 8 to 1. 2. In order to improve the anti-crack performance of the ultra-thin wear layer, we recommend that the HVHEAM adopt a dense skeleton structure, the optimal asphalt-to-aggregate ratio range is 7. 3% to 7. 9%, and the optimal filler-asphalt ratio range is 0. 8 to 1. 2. The research results can provide a reference for improving the anti-reflection crack performance of ultra-thin wear layer. [ABSTRACT FROM AUTHOR]

Elastic deformation and gaseous rarefaction effects are of great importance to the static and dynamic characteristics of gas microbearings. Based on the effective viscosity model of Veijola, the flexibility matrix was established by finite element method to calculate the elastic deformation of bearing shell surface, and the modified Reynolds equation considering the influence of effective viscosity and elastic deformation was deduced. The effects of bearing elastic modulus, gas effective viscosity, bearing structural parameters and disturbance frequency on the static and dynamic characteristics were analyzed by solving the modified Reynolds equation, effective viscosity equation and elasticity equations of ultra-thin gas film lubrication. The results indicate that the gaseous rarefaction effect significantly reduces the load carrying capacity of microbearings. The load carrying capacity of microbearing increases with the increase of eccentricity ratio and bearing number. Increasing the flexibility of bearing shell can improve the load carrying capacity and friction coefficient of microbearings, while the bearing capacity and friction coefficient of elastic microbearings considering the effective viscosity of gas are small. Compared with the rigid bearing, the reduction of the elastic modulus of the bearing shell significantly increases the dynamic stiffness coefficient and reduces the direct damping coefficient of the microbearings, while considering the gas effective viscosity effect caused by the rarefaction effect reduces the direct stiffness and increases the direct damping coefficient of the microbearings [ABSTRACT FROM AUTHOR]

Poly (ethylene terephthalate-butylene adipate) (PBAT) was modified by chain-extension reaction extrusion in a twin-screw extruder using a multi-component epoxy chain extender (ADR), and the effects of the addition amount of ADR on the content of terminal carboxyl groups, relative molecular weight, mechanical properties, crystallinity and color of PBAT were investigated. The results indicated that the terminal carboxyl group content of PBAT was reduced after the chain extension, and its mechanical properties and relative molecular weight were improved. The terminal carboxyl group content of PBAT decreased significantly from 2,3. 3 mol/t to 13. 8 mol/t when 1 wt% of ADR was added, and its relative molecular weight, crystallization temperature, and mechanical properties were also improved. Moreover, the maximum mechanical properties were achieved for PBAT when 1 wt% of ADR was added, and its elongation at break was higher than those of the other samples during the aging process. In addition, the PBAT after chain extension exhibited better aging resistance in view of its chemical structure as well as the relative molecular weight higher than the other samples during the aging process. [ABSTRACT FROM AUTHOR]

Objective: To explore the effectiveness of ultrasound-guided percutaneous Herbert screw for the treatment of fresh nondisplaced carpal scaphoid fracture., Methods: Between May 2013 and August 2015, 15 patients with fresh nondisplaced carpal scaphoid fractures (Krimmer type A2) were treated with ultrasound-guided Herbert screw fixation. There were 12 males and 3 females with an average age of 33.4 years (range, 18-51 years). The causes of injury included 9 cases of falls, 3 cases of training injuries, and 3 cases of machine injuries. The interval from injury to surgery was 2-15 days (mean, 5 days). No other complication was found. The operation time, intraoperative blood loss, intraoperative fluoroscopy times, and the fracture healing time were recorded. The wrist function was assessed by the modified Mayo wrist score standard., Results: The operation time was 28-53 minutes (mean, 33.9 minutes); the intraoperative blood loss was 5-30 mL (mean, 10.5 mL); the intraoperative fluoroscopy was 2-6 times (mean, 2.6 times). All 15 patients were followed up 6-18 months (mean, 10.5 months). One patient developed pain and soreness in the skin of the nail entrance, and gradually relieved after fumigation. No complication such as infection occurred. All fractures healed clinically, and the healing time was 8-16 weeks (mean, 11.6 weeks). At last follow-up, the modified Mayo wrist score was 76-99 (mean, 92.5). Among them, 12 cases were excellent, 2 cases were good, and 1 case was fair, and the excellent and good rate was 93.3%., Conclusion: Ultrasound-guided fixation with Herbert screw is a reliable treatment method for fresh nondisplaced carpal scaphoid fractures with small invasion, less bleeding, and small radiation damage.

Objective: To observe the early reperfusion therapy status for patients with ST elevation acute myocardial infarction (STEMI) hospitalized in tertiary and secondary hospitals in Henan province., Methods: Baseline data, early reperfusion treatment and in-hospital mortality of STEMI patients hospitalized in 17 hospitals in Henan province (8 tertiary hospitals, 9 secondary hospitals) from June 2011 to June 2012 were obtained using a uniformed questionnaire., Results: One thousand six hundred and eighty six patients were enrolled, of which 886 patients were hospitalized in tertiary hospitals and 880 patients were early hospitalized in secondary hospitals. Six hundred and fifty four patients (38.8%, 654/1 686) underwent early reperfusion therapy (543 with thrombolysis and 111 with primary percutaneous coronary intervention (PCI)). There was no difference in the proportion of early reperfusion therapy between tertiary and secondary hospitals (40.1% (355/886) vs. 37.4% (299/800), P = 0.257). The median time from symptom onset to first medical contact, door-to-needle and door-to-balloon was 132 min, 18 min and 60 min, respectively. The median time from symptom onset to first medical contact (150 min vs. 120 min, P = 0.001), door-to-needle (30 min vs. 18 min, P = 0.003) and symptom onset-to-thrombolysis (3.5 h vs. 2.7 h, P = 0.001) were significantly longer in tertiary hospitals than in secondary hospitals. No difference was found in median time of door-to-balloon, symptom onset-to-primary PCI or symptom onset-to-elected PCI between tertiary and secondary hospitals (all P > 0.05). The proportion of door-to-needle ≤ 30 min was lower in tertiary hospitals than in secondary hospitals (46.4% (84/181) vs. 62.2% (153/246), P = 0.001). However, there was no difference in the proportion of door-to-balloon ≤ 90 min between tertiary and secondary hospitals (58.8% (60/102) vs. 57.1% (4/7), P = 1.000). In-hospital mortality was also similar between tertiary and secondary hospitals (5.8% (51/886) vs. 5.5% (44/800), P = 0.820)., Conclusions: Early reperfusion rate is low, and thrombolysis is the main early reperfusion therapy in both tertiary and secondary hospitals in Henan province. Tertiary hospitals did not take advantage of their primary PCI capability. There is great room for improvement in early reperfusion therapy in tertiary and secondary hospitals.