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Novel non-invasive score to predict cirrhosis in the era of hepatitis c elimination: A population study of ex-substance users in Singapore

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Hepatobiliary & Pancreatic Diseases International 2019年第2期18卷 143-148页

作者： Yue Zhao Prem Harichander Thurairajah Rahul Kumar Jessica Tan Eng Kiong Teo John chen Hsiang Department of Gastroenterology and Hepatology Changi General Hospital

Background: chronic hepatitis c infection is common among people with history of substance use. Liver fibrosis assessment is a barrier to linkage to care, particularly among those with history of substance users. The use of non-invasive scores can be helpful in predicting liver cirrhosis in the era of HcV elimination, especially in countries where transient elastography(TE) is not available. We compared the commonly used non-invasive scores with a novel non-invasive score in predicting liver cirrhosis in this population. Methods: HcV patients with history of substance use between 2011 and 2016 were analyzed. All patients had TE for liver fibrosis assessment. clinical performance of established non-invasive scores for fibrosis assessment and novel score were compared. Youden's index was used to determine optimal cut-off of the novel score. Results: A total of 579 patients were included. In multivariate logistic regression, cirrhosis on TE was associated with age( P = 0.002), aspartate aminotransferase(AST)( P = 0.004), and platelet count( P < 0.001), but not alanine aminotransferase(ALT)( P = 0.896). These form the components of modified AST-toplatelet ratio index(APRI) score. Modified APRI was superior to APRI in predicting cirrhosis(AUROc, 0.796 vs. 0.770, P = 0.007), but not fibrosis-4 score(FIB-4)( P = 1.00). Modified APRI at cut-off of 4 has sensitivity, specificity and negative predictive value(NPV) of 94.4%, 26.9% and 92.6%, respectively, and at 19, has sensitivity, specificity and positive predictive value(PPV) of 33.3%, 96.2% and 77.1%, respectively. FIB-4 has a NPV and PPV of 88.6%, 41.8% and 78.5%, 77.6%, at cut-off of 1.45 and 3.25, respectively. Using the cut-off of 4 and 14 for modified APRI, 32.5% of patients can be correctly classified and misses out only 5.6% of cirrhosis patients. conclusions: Modified APRI score is superior in predicting cirrhosis in HcV population, with 32.5% of the population being correctly classified using cut-off of 4 and 14.

关键词： Hepatitis c cirrhosis Fibrosis assessment AST-to-platelet ratio index Modified APRI Fibrosis-4 score

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Effects of the c/N ratio on the microbial community and lignocellulose degradation, during branch waste composting

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BIOPROcESS AND BIOSYSTEMS ENGINEERING 2022年第7期45卷 1163-1174页

作者： Xie, Yuqing Zhou, Liuyan Dai, Jinping chen, Jing Yang, Xinping Wang, Xiaowu Wang, Zhifang Feng, Lei Xinjiang Acad Agr Sci Inst Microbiol Applicat Urumqi 830000 Peoples R China Xinjiang Key Lab Special Environm Microbiol Urumqi 830000 Peoples R China

Aerobic composting is an efficient and environmentally friendly method of converting organic waste into nontoxic fertilizers or soil quality enhancers. The quality of the resultant compost depends greatly upon the composition of the substrate used. The initial carbon-to-nitrogen (c/N) ratio of the substrate is an important factor affecting the composting process. This study elucidated how initial c/N ratios affect the biodegradation of lignocellulose, due to changes in microbial community structure. Four different c/N ratios (20:1, 25:1, 30:1, and 35:1) were examined during a 35-day composting process. The degradation of cellulose, hemicellulose, and lignin was highest (35.7%, 30.6%, and 19.1% respectively) at a 30:1 c/N ratio;after 30 days, the 25:1 c/N ratio ranked second in terms of lignocellulosic degradation rate. The 30:1 c/N ratio further promoted the growth of functional microorganisms responsible for lignocellulose degradation (Luteimonas, Sphingobium, Trichoderma, chaetomium, and Rosellinia), while the growth of dominant pathogenic microbes (Erwinia and Ulocladium) decreased significantly. These results confirm that the initial c/N ratio of the substrate has a significant effect on the microbial community and degradation of organic matter, during walnut branch composting. This process could therefore offer an alternative means of efficient recycling and recovery of waste branches.

关键词： composting Lignocellulose degradation c N ratio carbon emissions Microbial community

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A new clue for the pathogenesis of hepatitis c virus infection:Activation of the MAPK/ERK signaling initiated by envelope protein 2

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Science china(Life Sciences) 2003年第5期46卷 538-545页

作者：赵兰娟刘厚奇朱诗应冯根生戚中田 Department of Microbiology Second Military Medical University Shanghai 200433 China Department of Histology and Embryology Second Military Medical University Shanghai 200433 China Burnham Institute San Diego CA92037 USA

Since cell signal transduction plays an important role in disclosing the nature of human diseases, the pathogenesis of viruses may result from the disturbance of intracellular signal cascades caused by viral proteins. Hepatitis c virus (HcV) is a main causative agent of severe human liver disorders worldwide. So far, the mechanisms of HcV pathogenicity remain unclear. Envelope protein 2 (E2) of HcV is thought to be responsible for initiating virus attachment to host cells, which is a prerequisite of HcV infection. We assume that some early events of HcV pathogenic effects may result from the interaction of HcV E2 protein with its cellular receptor (human cD81), which could regulate cell proliferation and differentiation. To test this hypothesis, the effects of HcV E2 protein on MAPK/ERK pathway in Molt-4 and U937 cells with or without human cD81 expression were investigated. The results showed that HcV E2 protein could specifically activate the MAPK/ERK pathway, and such activation was inhibited by monoclonal antibodies against cD81 or HcV E2, serum antibodies from HcV infected patients, and upstream MEK1 inhibitor PD98059. Moreover, HcV E2-driven MAPK/ERK or downstream transcription factor Elk-1 activation was completely blocked in the presence of PD98059. These findings strongly suggest that the regulation of transmembrane signaling by HcV E2 protein via its receptor(s) on host cells might contribute to the development of HcV-related diseases.

关键词： hepatitis c virus, envelope protein 2, MAPK/ERK, signal transduction, pathogenesis.

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Modeling the Failure Time and Residual Strength of c/Sic composites under Stress-Oxidation Environment

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TRANSAcTIONS OF THE INDIAN cERAMIc SOcIETY 2020年第4期79卷 212-220页

作者： chen, Peng Niu, Xuming chen, Xihui Sun, Zhigang Zou, Pengjian Song, Yingdong Nanjing Univ Aeronaut & Astronaut Coll Energy & Power Engn Jiangsu Prov Key Lab Aerosp Power Syst Nanjing 210016 Peoples R China Sichuan Aerosp Syst Engn Inst Chengdu 610100 Peoples R China Minist Ind & Informat Technol Key Lab Aeroengine Thermal Environm & Struct Nanjing 210016 Peoples R China Nanjing Univ Aeronaut & Astronaut State Key Lab Mech & Control Mech Struct Nanjing 210016 Peoples R China

Based on the oxidation kinetics of c/Sic composites at 900o-1200oc in stress-oxidation environment, a non-uniform model of oxidation has been suggested in this paper. combined with fiber notch model, curtin's strength model and BHE model, the non-uniform model is able to predict the failure time and residual strength of c/Sic composites accurately. Besides, the initial defects of the model (matrix coating crack and open porosity), the effects of coating were taken into account, and the fiber strength and broken ratio were analyzed. Furthermore, the effects of oxidation time, stress, temperature, Si c coating thickness and volume fraction of fiber on the failure time and residual strength were discussed, and the predicted results showed a good consistency with the experimental data.

关键词： c Si c composites Stress-oxidation Failure time Residual strength Predictive model

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Effect of the incorporation of Sic nanowire with double protective layers on Sic coating for c/c composites

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JOURNAL OF THE EUROPEAN cERAMIc SOcIETY 2023年第11期43卷 4636-4644页

作者： Xie, Aolin Zhang, Bei Ge, Yicheng Peng, Ke Xu, Ping Wang, Xiaodong Feng, Zhirong Yi, Maozhong Zhou, Zhe Cent South Univ State Key Lab Powder Met Changsha 410083 Peoples R China Changsha Univ & Sci & Technol Coll Mat Sci & Engn Changsha 410114 Hunan Peoples R China

To maintain the thermal stability of Sic nanowires during Sic coating fabrication process, carbon and Sic double protective layers were covered on the surface of nanowires. And Sic nanowires with double protective layers toughened Sic coating were prepared by pack cementation. The results showed that after introducing the Sic nanowires with double protective layers, the fracture toughness of the Sic coating was increased by 88.4 %. The coating protected c/c for 175 h with a mass loss of 3.67 %, and after 51 thermal shock cycles, the mass losses of the oxidized coating were 3.96 %. The double protective layers are beneficial to improve the thermal stability of nanowires, leading to good fracture toughness and thermal shock resistance of Sic coating. Sic nanowires consume the energy of crack propagation by fracture, pullout and bridging, leading to an increase in fracture toughness.

关键词： c c composites Sic nanowire-toughened Sic coating Double protective layers Fracture toughness Oxidation resistance

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Formation of composite powders and ceramics from β-Sic-cr²O₃-c mixtures

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JOURNAL OF MATERIALS SYNTHESIS AND PROcESSING 2001年第4期9卷 187-197页

作者： Vlasova, MV Kakazey, NG Gonzales-Rodriguez, JG Mondragon, JJS Prilutskii, EV Tomila, TM Isaeva, LP Timofeeva, II Bukov, AI Gordienko, SP UAEM Ctr Res Engn & Appl Sci Cuernavaca Morelos Mexico Natl Acad Sci Ukraine Inst Problems Mat Sci Kiev Ukraine

The phase-formation process in the disperse beta-Sic + SiO2 + cr2O3 + c system treated in vacuum at 1273, 1473, 1673, and 1873 K was studied by X-ray phase analysis, IR spectroscopy, EPR, and other methods. It was found that at treatment temperatures of 1273, 1473, and 1673 K, the major process is carbothermal reduction of cr2O3 and SiO2 with the formation of chromium carbosilicide and chromium carbide (cr3c2). At T = 1873 K, on the surface of the Sic particles, metastable chromium silicate forms on the base of SiO2 and cr2O3. The reduction of cr2SiO4 by silicon carbide is accompanied by the formation of crSi2, cr5Si3, and chromium carbosilicide. The phase composition of the products of interaction and their distribution over the volume of the composite powder and ceramic material are determined by the dispersion composition of the starting Sic powder and by the degree of development of reduction processes in local volumes of the disperse and compacted material.

关键词： beta-Sic cr2O3 SiO2 c interaction silicide formation

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A chromium carbide coating in-situ formed on c/c composites by the novel reactive wetting strategy to enhance oxidation resistance

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JOURNAL OF THE EUROPEAN cERAMIc SOcIETY 2022年第14期42卷 6435-6444页

作者： Guo, Xiajun Si, Xiaoqing Liu, Yongxu Zhao, Wendi Wang, Xiaoyang Li, chun Qi, Junlei cao, Jian Harbin Inst Technol State Key Lab Adv Welding & Joining Harbin 150001 Peoples R China

A chromium carbide (cr-c) coating in-situ formed on the c/c substrate is successfully prepared by a novel reactive wetting strategy. The interfacial microstructure and oxidation resistance of coated c/c composites are investigated in detail. The as-prepared coating mainly consists of cr23c6 and cr7c3, forming a tight joining with the c/c substrate. compared to uncoated samples, the oxidation weight loss of coated c/c composites is sub-stantially reduced at high temperatures. Furthermore, the hardness of coated c/c composites is significantly increased, enhancing their ability to resist external damage. This reactive wetting strategy can also be used to prepare uniform coatings on c/c composites with complex grooved structure or large size. Surprisingly, coated c/c composites possess a low weight gain of 3.7% due to thin coating (< 10 mu m), which can maintain their advantage of low density.

关键词： c c composites chromium carbide coating Oxidation resistance cr2O3

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Ba, Si, U, Al, Sc, La, Th, c and ¹³c/¹²c in a sediment core in the western subarctic Pacific as proxies of past biological production

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MARINE cHEMISTRY 2007年第3-4期106卷 442-455页

作者： Shigemitsu, Masahito Narita, Hisashi Watanabe, Yutaka W. Harada, Naomi Tsunogai, Shizuo Hokkaido Univ Grad Sch Environm Sci Sapporo Hokkaido 0600810 Japan Tokai Univ Sch Marine Sci & Technol Shizuoka 4248610 Japan Japan Agcy Marine Earth Sci & Technol Inst Observat Res Global Change Yokosuka Kanagawa 2370061 Japan

A sediment core covering the last 145 kyrs was collected in the western subarctic Pacific (WSAP), and analyzed for Ba, U, Al, Sc, La, Yb, Th, biogenic opal (Opal) and organic carbon (c-org) as well as its isotopic ratio (delta(13) c). This study examined the change of past biological production in WSAP with multiple proxies, together with understanding the relation between Loess from the Asian continent and the biological production. The Loess content was estimated from the metal components, Al, Sc, La, Yb and Th. In this high latitude core (50 degrees N), the Loess content was generally high during the glacial periods, but it was also high even in some interglacial periods. The excess amount of Ba relative to the detrital material composition, Ba-ex, showed the best correlation with the Vostok delta D (r= 0.72, p < 0.001), indicating that the biological production was lower in the glacial periods than in the interglacials. This corroborates the pervasive correlation between Ba-ex in the polar region, WSAP and the Antarctic Sea, and Antarctic temperature, combined with previous research. This correlation might be explained by the stratification caused by cooling. In addition, the time variations of Ba-ex in WSAP were similar to those of Ba-ex in the Okhotsk Sea and of other proxies (c-org, and Opal) in both the Okhotsk and the Bering Sea, indicating the spatial homogeneity of Ba-ex in WSAP including proximal marginal seas. The Opal content was more weakly correlated with the Vostok delta D (r= 0.46, p < 0.001) than Ba-ex, reflecting that Opal in WSAP including proximal marginal seas was spatially heterogeneous compared to Ba-ex. While both the c-org content and U-ex, the excess amount of U relative to the detritus composition, were not positively correlated with the Vostok delta D, they behaved similarly in the sediments. The positive correlation between delta c-13 and the Vostok delta D (r = 0.42, p < 0.001), between 613 c and Ba,x (r= 0.60, p < 0.00 1) and between

关键词： Ba opal c c-13/c-12 U eolian dust sediment North Pacific

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Dosimeter properties of MgO transparent ceramic doped with c

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RADIATION MEASUREMENTS 2016年第0期92卷 93-98页

作者： Kato, Takumi Okada, Go Yanagida, Takayuki Nara Inst Sci & Technol NAIST 8916-5Takayama Cho Ikoma Nara 6300192 Japan

We have investigated the photoluminescence (PL), scintillation and thermally-stimulated luminescence (TSL) dosimeter properties of MgO ceramic doped with c ions (0.001, 0.01 and 0.1%). The samples were synthesized by a Spark Plasma Sintering (SPS) technique. The PL emission peaks appeared around 400 and 750 nm in all the samples. The PL decay time constants at 400 nm were 10 and 100 ns which were on the typical order of F+ center in the undoped MgO. The scintillation emission peaks were detected at 330, 400 and 750 nm under X-ray irradiation. The TSL glow curves showed the 250 degrees c peak in 0.1% c doped sample. The TSL response was confirmed to be linear to the irradiation dose over the dose range from 0.1 to 1000 mGy. As a result, the sensitivity of MgO was improved by c-doping. (c) 2016 Elsevier Ltd. All rights reserved.

关键词： Transparent ceramic MgO c Dosimeter TSL

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Mechanical property and toughening mechanism of 2.5D c/c-Sic composites with high textured pyrocarbon interface

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cERAMIcS INTERNATIONAL 2021年第20期47卷 29183-29190页

作者： Xu, Jing Guo, Lingjun Wang, Hanhui Li, Kaijiao Wang, Tiyuan Li, Wei Northwestern Polytech Univ Carbon Carbon Composites Res Ctr State Key Lab Solidificat Proc Xian 710072 Shaanxi Peoples R China

The application of c/c-Sic composites remains a challenge because of the poor mechanical properties induced by the liquid silicon infiltration method. In this study, a thick high textured pyrolytic carbon (HT Pyc) interface manufactured by chemical vapor infiltration (cVI) was used to protect the carbon fibers and improve the flexural properties. The microstructure of HT Pyc, its flexural properties, and its associated strengthening and toughening mechanisms were analyzed on the c/c-Sic composites. The results showed that the bending strength of the c/cSic composites was 344.74 MPa, which is nearly 31.82% higher than that of c/c composites. The fracture mode transformed from brittle fracture to pseudoplastic fracture owing to the addition of Sic, and the c/c-Sic composites maintained a better toughness compared to c/c composites. Multiple mechanisms of strength and toughness improvement were found to be responsible for the excellent performance of the c/c-Sic composites. The HT Pyc interface played a critical role in the excellent flexural properties. The strong bonding among the carbon layers and high interfacial strength between the fiber and HT Pyc led to the increase of strength. Besides, the improvement in toughness was attributed to the multiple effects of the carbon-layers deformation, cracks deflection and propagation caused by the bridging areas, sublayers, nano-and micro-scale cracks.

关键词： c c-Sic composites High textured pyrocarbon interface Morphology Flexural property

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