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COVID-19:A pluralistic and integrated approach for efficient management of the pandemic 被引量:2
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作者 Nouhoum Bouare Daouda Kassim Minta +1 位作者 Abdoulaye Dabo Christiane Gerard 《World Journal of Virology》 2022年第1期20-39,共20页
The novel severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),which triggered the ongoing pandemic,was first discovered in China in late 2019.SARSCoV-2 is a respiratory virus responsible for coronavirus diseas... The novel severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),which triggered the ongoing pandemic,was first discovered in China in late 2019.SARSCoV-2 is a respiratory virus responsible for coronavirus disease 2019(COVID-19)that often manifests as a pneumonic syndrome.In the context of the pandemic,there are mixed views on the data provided by epidemiologists and the information collected by hospital clinicians about their patients.In addition,the literature reports a large proportion of patients free of pneumonia vs a small percentage of patients with severe pneumonia among confirmed COVID-19 cases.This raises the issue of the complexity of the work required to control or contain the pandemic.We believe that an integrative and pluralistic approach will help to put the analyses into perspective and reinforce collaboration and creativity in the fight against this major scourge.This paper proposes a comprehensive and integrative approach to COVID-19 research,prevention,control,and treatment to better address the pandemic.Thus,this literature review applies a pluralistic approach to fight the pandemic. 展开更多
关键词 SARS-CoV-2 COVID-19 PANDEMIC Pluralistic approach Global approach Efficient management
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Changes of pigments and lipids composition in Haematococcus pluvialis vegetative cell as affected by monochromatic red light compared with white light
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作者 朱小娟 罗杰 +6 位作者 周成旭 王建沅 孟冉 徐继林 陈娟娟 骆其君 严小军 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第6期2257-2267,共11页
Much attention has been paid on studies of astaxanthin accumulation process in H aematococcus pluvialis industry. However, growth of H. pluvialis in motile vegetative stage is still the most important and problematic ... Much attention has been paid on studies of astaxanthin accumulation process in H aematococcus pluvialis industry. However, growth of H. pluvialis in motile vegetative stage is still the most important and problematic part in the whole cultivation process, such as low growth rate and cell yields. Motile vegetative cells are extremely sensitive to various stresses which make it difficult to maintain the cells of this state to grow. Previous reports showed that motile vegetative cells may have higher biomass yields ifapplied monochromatic red light. However, metabolic responses of these cells are not completely understood, which constraints application of this illumination protocol in industry. The aim of this study was to examine how critical biochemical changes of H. pluvialis motile vegetative cells were af fected by red light when compared with white light. Variation of photosynthetic pigments composition and lipids were mainly studied. By comparing growth process of cultures in red light and white light, prominent variation of pigments composition and lipids changes were observed. The results showed that, even though cell proliferation was the same during exponential growth phase, variation of photosynthetic pigment composition and lipids occurred. The final biomass of cell number was higher in red light group than in white light group. The variations were significant different. Increase or decrease of major photosynthetic membrane lipids to some extent did not influence photosynthesis of the vegetative cells during this phase. However, vegetative cells under polychromatic white light other than monochromatic red light need further metabolic process to adjust its pigment composition and lipids, possibly this is energetically and biochemically unfavorable for motile vegetative cells to growth under white light, a light condition normally not considered as a stress. 展开更多
关键词 HAEMATOCOCCUS pluvialis light quality PHOTOSYNTHETIC PIGMENTS neutral lipid PHOTOSYNTHETIC membrane LIPIDS
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Characterization of the Bacillus subtilis Penicillin-Binding Protein PBP4
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作者 Arnaud Vanden Broeck Eric Sauvage +1 位作者 Bernard Joris Colette Duez 《Advances in Microbiology》 2019年第3期164-176,共13页
Purpose: The PBP4* is a Penicillin Binding Protein belonging to the class C of AmpH type whose function remains poorly understood. This study aimed to evaluate the biophysical and enzymatic properties of the Bacillus ... Purpose: The PBP4* is a Penicillin Binding Protein belonging to the class C of AmpH type whose function remains poorly understood. This study aimed to evaluate the biophysical and enzymatic properties of the Bacillus subtilis PBP4* to gain insights into its role in the context of bacterial cell wall recycling. Methods: To characterize the PBP4*, the full-length PBP4* and its N-terminal penicillin-binding domain have been produced in Escherichia coli and purified. Results: A comparison of biophysical properties has shown that both recombinant proteins are monomeric in solution and retain the same thermal stability. On the other hand, the D-alanine methyl esterase activity detected with the full-length PBP4* is impeded by the cleavage of the 92 amino acid C-terminal domain. The esterase activity of the full-length PBP4* strates a clear D-stereospecificity. The PBP4* is also active on B. subtilis cell walls bearing teichoic acids, compounds commonly substituted with D-alanine residues. Conclusions: Our results are in agreement with the hypothesis that PBP4* could play a role in recycling cell wall components, as previously suggested. 展开更多
关键词 B. SUBTILIS PBP4* Class-C PBP D-Stereospecific ESTERASE
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For a Holistic View of Biotechnology in West and Central Africa: What Can Integrated Development Approaches Contribute?
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作者 Francis Rosillon 《Journal of Environmental Protection》 2013年第9期975-983,共9页
Africa, ever on the lookout for development levers that will allow its economy to take off, is turning more and more towards technology. This is one of the possible modern avenues to success, especially the use of the... Africa, ever on the lookout for development levers that will allow its economy to take off, is turning more and more towards technology. This is one of the possible modern avenues to success, especially the use of the biotechnologies that are so touted by Western countries. However, the hope placed in these new technologies must not hide the long-proven fact that technology alone is not enough to solve development problems. Biotechnologies do not escape this rule. Biotechnologies can be the best and the worst things for the people of Africa. Beyond their technical contributions, we must be wary of their boomerang effects and collateral damage. A country’s development is actually more complex than simply implementing technology, and in the current global environmental context a holistic vision is necessary to ensure sustainable development. In the area of water, this integrated vision emerged on the international scene during the Dublin Conference in 1992, which consecrated the principles of Integrated Water Resources Management (IWRM). More recently, the Eco-Health concept strives to combine human health and ecosystem health while incorporating a socioeconomic dimension into the health and environmental spheres. The concern to mesh human activities better with environmental protection was materialized previously, in the 1970s already, through impact studies. After presenting this set of tools in the service of a holistic approach to the environment and development, we shall see that these approaches can inspire the players when it comes to the ways they implement biotechnologies. At the end of the day, a holistic approach to biotechnologies in Africa will be facilitated by enhanced information and communication and reliance on peasant farmers’ expertise. It will have to be rooted in broader participation of the players concerned. This integration will also concern environmental and land-owning aspects, without forgetting socio-cultural acceptance of the projects and the links with health. Ultimately, it will also mean putting the human at the heart of development by taking all the richness and particularities of African society into account. 展开更多
关键词 BIOTECHNOLOGY AFRICA Development Integration HOLISTIC Approach
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Recent Advance in Division of Carbohydrate and Protein Fractions of Ruminant Feed and Their Metabolism in Digestive Tract
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作者 Xiaohua PAN Liang YANG +1 位作者 Hairui XIN Benhai XIONG 《Asian Agricultural Research》 2016年第7期78-83,共6页
Accurate assessment of feed's Carbohydrate( CHO) and protein nutritional values and rumen metabolism are significant for dairy production. Cornell Net Carbohydrate and Protein System( CNCPS) as an important method... Accurate assessment of feed's Carbohydrate( CHO) and protein nutritional values and rumen metabolism are significant for dairy production. Cornell Net Carbohydrate and Protein System( CNCPS) as an important method to evaluate feedstuff nutritional values,hasn't been widely used in China. In order to illustrate updates of CNCPS systems deeply,the following sections were reviewed:( i) CHO and protein fractions were updated,CA was subdivided into CA1,CA2,CA3 and CA4 in CNCPS v6. 1,protein was reclassified into PA1,PA2,PB1,PB2 and PC after CNCPS v6. 1. Content of CHO and protein fractions vary in different feedstuff and affected by feed processing;( ii) Degradation rates( Kd) values for the new CA expanded scheme were updated to 0,7,5,40- 60 % h^(-1)respectively,Kd for PA and PB1 decreased to 200 % h^(-1)and 10- 40 % h^(-1);( iii) Equations for passage rate( Kp) initially includes Kpf( Kp of forages) and Kpc( Kp of concentrates),and adjusted by effective NDF( e NDF),while in CNCPS v5. 0,Kpl( Kp of liquids) equation was added and e NDF was replaced by physically effective NDF( pe NDF). In CNCPS v6. 1,Fp BW and Cp BW were integrated into Kp equations and pe NDF was abandoned.( iv)The relationship and difference among Weende system of proximate analysis,Van Soest fiber analysis~[35],NRC( 2001)~[28]and CNCPS were analyzed. The first two systems laid the foundation for NRC( 2001) and CNCPS system. The latter two systems are different in CHO and protein division,also NRC( 2001) developed separate Kp equations for wet and dry forages but no equation for Kpl. CNCPS developed a Kp equation that work for wet and dry forages,and Kpl equation was established. In conclusion,the division and development of CHO and protein fractions,the update of Kd and Kp equation were reviewed systematically. 展开更多
关键词 CNCPS CARBOHYDRATE Protein FRACTION METABOLISM
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Editorial on photoreceptor glucose metabolism determines normal retinal vascular growth
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作者 Amy C.Lo 《Annals of Eye Science》 2018年第1期88-91,共4页
Retinopathy of prematurity(ROP)was first described as a disease of prematurity(1).There was then a worldwide epidemic of ROP,which contributed to 50%blindness in 1950.Later vigorous research showed a correlation betwe... Retinopathy of prematurity(ROP)was first described as a disease of prematurity(1).There was then a worldwide epidemic of ROP,which contributed to 50%blindness in 1950.Later vigorous research showed a correlation between the use of supplemental oxygen and the incidence and progression of ROP.This led to a close monitoring of supplemental oxygen given to premature infants,which helped to decrease the percentage of ROP-related blindness to 4%in 1965.Yet,the incidence of ROP increased in recent years,presumably due to great improvement in neonatal care,which in turn resulted in increased survival of very-low-birth-weight premature infants. 展开更多
关键词 metabolism PREMATURE NEONATAL
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McMYB4 improves temperature adaptation by regulating phenylpropanoid metabolism and hormone signaling in apple
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作者 Suxiao Hao Yanfen Lu +4 位作者 Zhen Peng Enying Wang Linke Chao Silin Zhong Yuncong Yao 《Horticulture Research》 SCIE 2021年第1期2319-2332,共14页
Temperature changes affect apple development and production.Phenylpropanoid metabolism and hormone signaling play a crucial role in regulating apple growth and development in response to temperature changes.Here,we fo... Temperature changes affect apple development and production.Phenylpropanoid metabolism and hormone signaling play a crucial role in regulating apple growth and development in response to temperature changes.Here,we found that McMYB4 is induced by treatment at 28℃ and 18℃,and McMYB4 overexpression results in flavonol and lignin accumulation in apple leaves.Yeast one-hybrid(Y1H)assays and electrophoretic mobility shift assays(EMSAs)further revealed that McMYB4 targets the promoters of the flavonol biosynthesis genes CHS and FLS and the lignin biosynthesis genes CAD and F5H.McMYB4 expression resulted in higher levels of flavonol and lignin biosynthesis in apple during growth at 28℃ and 18℃ than during growth at 23℃.At 28℃ and 18℃,McMYB4 also binds to the AUX/ARF and BRI/BIN promoters to activate gene expression,resulting in acceleration of the auxin and brassinolide signaling pathways.Taken together,our results demonstrate that McMYB4 promotes flavonol biosynthesis and brassinolide signaling,which decreases ROS contents to improve plant resistance and promotes lignin biosynthesis and auxin signaling to regulate plant growth.This study suggests that McMYB4 participates in the abiotic resistance and growth of apple in response to temperature changes by regulating phenylpropanoid metabolism and hormone signaling. 展开更多
关键词 PHENYL ACCELERATION METABOLISM
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Beneficial mechanisms of aerobic exercise on hepatic lipid metabolism in non-alcoholic fatty liver disease 被引量:16
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作者 Rui Guo Emily C Liong +2 位作者 Kwok Fai So Man-Lung Fung George L Tipoe 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2015年第2期139-144,共6页
BACKGROUND:Non-alcoholic fatty liver disease(NAFLD)refers to any fatty liver disease that is not due to excessive use of alcohol.NAFLD probably results from abnormal hepatic lipid metabolism and insulin resistance.... BACKGROUND:Non-alcoholic fatty liver disease(NAFLD)refers to any fatty liver disease that is not due to excessive use of alcohol.NAFLD probably results from abnormal hepatic lipid metabolism and insulin resistance.Aerobic exercise is shown to improve NAFLD.This review aimed to evaluate the molecular mechanisms involved in the beneficial effects of aerobic exercise on NAFLD.DATA SOURCE:We searched articles in English on the role of aerobic exercise in NAFLD therapy in Pub Med.RESULTS: The mechanisms of chronic aerobic exercise in regulating the outcome of NAFLD include: (i) reducing in- trahepatic fat content by down-regulating sterol regulatory element-binding protein-lc and up-regulating peroxisome proliferator-activated receptor y expression levels; (ii) decreas- ing hepatic oxidative stress through modulating the reactive oxygen species, and enhancing antioxidant enzymes such as catalase and glutathione peroxidase; (iii) ameliorating hepatic inflammation via the inhibition of pro-inflammatory media- tors such as tumor necrosis factor-alpha and interleukin-1 beta; (iv) attenuating mitochondrial dependent apoptosis by reducing cytochrome C released from the mitochondria to the cytosol; and (v) inducing hepato-protective autophagy. CONCLUSION: Aerobic exercise, via different mechanisms, significantly decreases the fat content of the liver and improves the outcomes of patients with NAFLD. 展开更多
关键词 non-alcoholic fatty liver disease chronic aerobic exercise oxidative stress inflammation apoptosis autophagy
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Establishment of an orthotopic transplantation tumor model of hepatocellular carcinoma in mice 被引量:4
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作者 Gui-Jun Zhao Li-Xia Xu +4 位作者 Eagle SH Chu Ning Zhang Jia-Yun Shen Alatangaole Damirin Xiao-Xing Li 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第47期7087-7092,共6页
AIM:To improve the outcome of orthotopic transplantation in a mouse model,we used an absorbable gelatin sponge(AGS) in nude mice to establish an orthotopic implantation tumor model.METHODS:MHCC-97L hepatocellular carc... AIM:To improve the outcome of orthotopic transplantation in a mouse model,we used an absorbable gelatin sponge(AGS) in nude mice to establish an orthotopic implantation tumor model.METHODS:MHCC-97L hepatocellular carcinoma(HCC)cells stably expressing the luciferase gene were injected into the subcutaneous region of nude mice.One week later,the ectopic tumors were harvested and transplanted into the left liver lobe of nude mice.The AGS was used to establish the nude mouse orthotopic implantation tumor model.The tumor suppressor gene,paired box gene 5(PAX5),which is a tumor suppressor in HCC,was transfected into HCC cells to validate the model.Tumor growth was measured by bioluminescence imaging technology.Semi-quantitative reverse transcription polymerase chain reaction(RT-PCR) and histopathology were used to confirm the tumorigenicity of the implanted tumor from the MHCC-97L cell line.RESULTS:We successfully developed an orthotopic transplantation tumor model in nude mice with the use of an AGS.The success rate of tumor transplantation was improved from 60% in the control group to 100% in the experimental group using AGS.The detection of fluorescent signals showed that tumors grew in all live nude mice.The mice were divided into 3 groups:AGS-,AGS+/PAX5-and AGS+/PAX5 +.Tumor size was significantly smaller in PAX5 transfected nude mice compared to control mice(P < 0.0001).These fluorescent signal results were consistent with observations made during surgery.Pathologic examination further confirmed that the tissues from the ectopic tumor were HCC.Results from RT-PCR proved that the HCC originated from MHCC-97L cells.CONCLUSION:Using an AGS is a convenient and efficient way of establishing an indirect orthotopic liver transplantation tumor model with a high success rate. 展开更多
关键词 肝细胞肝癌 小鼠模型 细胞移植 原位 肿瘤抑制基因 反转录聚合酶链反应 荧光素酶基因 RT-PCR
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Establishment and characterization of a new cell line derived from human colorectal laterally spreading tumor 被引量:5
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作者 Xin-Ying Wang Zhou-Sheng Lai +7 位作者 Chung-Man Yeung Ji-De Wang Wen Deng Hoi Yee Li Yu-Jing Han Hsiang-Fu Kung Bo Jiang Marie Chia-mi Lin 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第8期1204-1211,共8页
AIM:To study the molecular mechanism of laterally spreading tumor (LST), a cell line [Laterally Spreading Tumor-Rectum 1 (LST-R1)] was derived and the characteristics of this cell line were investigated. METHODS:A new... AIM:To study the molecular mechanism of laterally spreading tumor (LST), a cell line [Laterally Spreading Tumor-Rectum 1 (LST-R1)] was derived and the characteristics of this cell line were investigated. METHODS:A new cell line (LST-R1) originated from laterally spreading tumor was established. Properties of the cell line were characterized using scanning and transmission electron microscopy, immunohistochemistry method, cytogenetic analysis and nude mice xenograft experiments. In vitro invasion assay, cDNA microarray and Western blotting were used to compare the difference between the LST-R1 and other colorectal cancer cell lines derived from prudent colon cancer. RESULTS:Our study demonstrated that both epithelial special antigen (ESA) and cytokeratin-20 (CK20) were expressed in LST-R1. The cells presented microvilli and tight junction with large nuclei. The karyotypic analysis showed hyperdiploid features with structural chromosome aberrations. The in vivo tumorigenicity was also demonstrated in nude mice xenograft experiments. The invasion assay suggested this cell line has a higher invasive ability. cDNA microarray and Western blotting show the loss of the expression of E-cadherin in LST-R1 cells.CONCLUSION:We established and characterized a colorectal cancer cell line, LST-R1 and LST-R1 has an obvious malignant tendency, which maybe partially attributed to the changes of the expression of some adhesion molecules, such as E-cadherin. It is also a versatile tool for exploring the original and progressive mechanisms of laterally spreading tumor and the early colon cancer genesis. 展开更多
关键词 结肠直肠肿瘤 分子机制 肿瘤细胞 LST-R1
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Complete genome sequence of the rifamycin SV-producing Amycolatopsis mediterranei U32 revealed its genetic characteristics in phylogeny and metabolism 被引量:11
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作者 Wei Zhao Yi Zhong +23 位作者 Hua Yuan Jin Wang Huajun Zheng Ying Wang Xufeng Cen Feng Xu Jie Bai Xiaobiao Han Gang Lu Yongqiang Zhu Zhihui Shao Han Yan Chen Li Nanqiu Peng Zilong Zhang Yunyi Zhang Wei Lin Yun Fan Zhongjun Qin Yongfei Hu Baoli Zhu Shengyue Wang Xiaoming Ding Guo-Ping Zbao 《Cell Research》 SCIE CAS CSCD 2010年第10期1096-1108,共13页
Amycolatopsis mediterranei 被用于 rifamycin 的工业规模生产,它在 antimycobacterial 治疗起一个重要作用。作为类 Amycolatopsis 的首先定序的染色体, 236 715 底配对的包括 10 的紧张 U32 的染色体,最大的原核生物的染色体之一... Amycolatopsis mediterranei 被用于 rifamycin 的工业规模生产,它在 antimycobacterial 治疗起一个重要作用。作为类 Amycolatopsis 的首先定序的染色体, 236 715 底配对的包括 10 的紧张 U32 的染色体,最大的原核生物的染色体之一到目前为止曾经被定序。不同于在 streptomycetes 发现的线性拓扑学,这个染色体是圆形的,特别地类似于 Saccharopolyspora erythraea 和奴卡氏菌属 farcinica,在发展史和分类代表他们的靠近的关系。尽管在 A 预言了 9 228 编码蛋白质的基因。mediterranei 染色体 S 与那些分享了 orthologs 的最大的数字。erythraea,它被 Streptomyces coelicolor 而非 N 出人意料地跟随。farcinica,显示不同新陈代谢的特征经由改编演变到多样的生态的壁龛。除类似于那的一个核心区域以外在 streptomycetes 普通,有典型核心特征的一个新奇“伪核心”在非核心区域以内被定义,在 21 从 26 基因为第二等的代谢物生产聚类的总数被定位的地方。位于核心的 rifamycin 生合成基因簇为 rifamycin SV 的变换编码细胞色素 P450 酶必需品到 B,由比作 rifamycin 生产 B 紧张 S699 的高度相应的簇揭示了并且进一步由基因互补证实了。A 的 genomic 信息。mediterranei 表明在看起来复杂的规章的机制的控制下面不仅为各种各样的碳来源和无机的氮混合物的广泛的利用而且为新陈代谢的中介的有效 funneling 安排进第二等的抗菌素合成进程的一个新陈代谢的网络。 展开更多
关键词 利福霉素SV 基因组序列 规模生产 代谢特征 遗传特征 系统发育 生物合成基因簇 细胞色素P450酶
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Pun Translation in English Advertisement
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作者 李会芹 《海外英语》 2015年第20期239-240,共2页
With the development of globalization and the increasing commodity circulation among countries, advertisement as one of the most effective promoting methods, has also transcended the boundaries of countries and attrac... With the development of globalization and the increasing commodity circulation among countries, advertisement as one of the most effective promoting methods, has also transcended the boundaries of countries and attracted more attentions. In order to make their advertisements vivid, impressing, attracting and increase the customers' desire to purchase, advertisers would make advantage of rhetorical devices to achieve this effect. Among them, pun is one of the widely used devices. This thesis aims to discuss the language features of English advertising and puns. The author hopes this article can be beneficial to the polishing of pun in advertising translation and offer the reference for advertising translation. 展开更多
关键词 ADVERTISING TRANSLATION PUN PUN TRANSLATION TRANSLATION STRATEGIES
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Signaling pathways in cancer metabolism:mechanisms and therapeutic targets 被引量:1
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作者 Mengshu You Zhuolin Xie +6 位作者 Nan Zhang Yixuan Zhang Desheng Xiao Shuang Liu Wei Zhuang Lili Li Yongguang Tao 《Signal Transduction and Targeted Therapy》 SCIE CSCD 2023年第6期2550-2576,共27页
A wide spectrum of metabolites(mainly,the three major nutrients and their derivatives)can be sensed by specific sensors,then trigger a series of signal transduction pathways and affect the expression levels of genes i... A wide spectrum of metabolites(mainly,the three major nutrients and their derivatives)can be sensed by specific sensors,then trigger a series of signal transduction pathways and affect the expression levels of genes in epigenetics,which is called metabolite sensing.Life body regulates metabolism,immunity,and inflammation by metabolite sensing,coordinating the pathophysiology of the host to achieve balance with the external environment.Metabolic reprogramming in cancers cause different phenotypic characteristics of cancer cell from normal cell,including cell proliferation,migration,invasion,angiogenesis,etc.Metabolic disorders in cancer cells further create a microenvironment including many kinds of oncometabolites that are conducive to the growth of cancer,thus forming a vicious circle.At the same time,exogenous metabolites can also affect the biological behavior of tumors.Here,we discuss the metabolite sensing mechanisms of the three major nutrients and their derivatives,as well as their abnormalities in the development of various cancers,and discuss the potential therapeutic targets based on metabolite-sensing signaling pathways to prevent the progression of cancer. 展开更多
关键词 METABOLISM THERAPEUTIC IMMUNITY
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The chemical reprogramming of unipotent adult germ cells towards authentic pluripotency and de novo establishment of imprinting
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作者 Yuhan Chen Jiansen Lu +12 位作者 Yanwen Xu Yaping Huang Dazhuang Wang Peiling Liang Shaofang Ren Xuesong Hu Yewen Qin Wei Ke Ralf Jauch Andrew Paul Hutchins Mei Wang Fuchou Tang Xiao-Yang Zhao 《Protein & Cell》 SCIE CSCD 2023年第7期479-498,共20页
Although somatic cells can be reprogrammed to pluripotent stem cells(PsCs)with pure chemicals,authentic pluripotency of chemically induced pluripotent stem celis(CipsCs)has never been achieved through tetraploid compl... Although somatic cells can be reprogrammed to pluripotent stem cells(PsCs)with pure chemicals,authentic pluripotency of chemically induced pluripotent stem celis(CipsCs)has never been achieved through tetraploid complementation assay.Spontaneous reprogramming of spermatogonial stem cells(ssCs)was another non-transgenic way to obtain PsCs,but this process lacks mechanistic explanation.Here,we reconstructed the trajectory of mouse SsC reprogramming and developed a five-chemical combination,boosting the reprogramming effciency by nearly 80-to 100-folds.More importantly,chemical induced germline-derived PsCs(5C-gPSCs),but not gpsCs and chemical induced pluripotent stem cells,had authentic pluripotency,as determined by tetraploid complementation.Mechanistically,ssCs traversed through an inverted pathway of in vivo germ ceil development,exhibiting the expression signatures and DNA methylation dynamics from spermatogonia to primordial germ cells and further to epiblasts.Besides,ssC-specific imprinting control regions switched from biallelic methylated states to monoallelic methylated states by imprinting demethylation and then re-methylation on one of the two alleles in 5c-gPsCs,which was apparently distinct with the imprinting reprogramming in vivo as DNA methylation simultaneously occurred on both alleles.Our work sheds ight on the unique regulatory network underpinning SsC reprogramming,providing insights to understand generic mechanisms for cell-fate decision and epigenetic-relateddisorders in regenerative medicine. 展开更多
关键词 REPROGRAMMING spermatogonial stem cell tetraploid complementation IMPRINTING
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钛合金气门在高海拔环境中的应用优势与表面处理
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作者 郭思良 张健 +2 位作者 王海军 陈文刚 程家豪 《材料保护》 CAS CSCD 2024年第5期105-118,共14页
在高海拔环境下,低温低压环境会导致柴油发动机的动力下降和燃烧不完全,这也会导致气门组件磨损加剧。虽然几十年来,气门制造技术已经得到了广泛探索,但是气门组件经常面临高温高压、频繁冲击和摩擦的严峻工作条件,导致摩擦磨损机制变... 在高海拔环境下,低温低压环境会导致柴油发动机的动力下降和燃烧不完全,这也会导致气门组件磨损加剧。虽然几十年来,气门制造技术已经得到了广泛探索,但是气门组件经常面临高温高压、频繁冲击和摩擦的严峻工作条件,导致摩擦磨损机制变得异常复杂,过去的气门制造优化措施并没有完全解决气门组件磨损的问题。为此,提出了一种新的解决方案,即使用铝化钛合金作为气门材料。该材料具有热强度高和重量轻的优点,非常适合用作柴油发动机气门材料。然而,由于钛铝合金的耐磨性存在短板,因此在投入实际使用之前,需要通过表面处理工艺来改善其摩擦学性能和疲劳特性。总结了多种钛铝合金表面处理方法的研究情况,包括超声表面轧制、激光表面熔覆技术、化学热处理工艺、激光表面微织构等。这些表面处理技术可以有效地改善铝化钛合金材料的摩擦学性能和疲劳特性,并消除对材料表面的负面影响。研究者们还通过使用不同的表面处理技术的复合处理来达到更好的效果。指出了未来的研究重点和方向是深入研究铝化钛合金的精确加工参数以及使用多种加工方式的可行性和作用。这将有助于更好地解决气门组件的磨损问题,提高柴油发动机的性能和可靠性。此外,还需要对铝化钛合金在其他领域的应用进行更广泛地研究和探索。 展开更多
关键词 高海拔环境 气门组件 铝化钛合金材料 表面处理技术
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3D打印铸造铝合金表面楔形织构的摩擦性能
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作者 程家豪 陈文刚 +4 位作者 陈红艳 郭思良 袁浩恩 魏北朝 张露漫 《功能材料》 CAS CSCD 北大核心 2024年第4期4161-4166,共6页
实验对活塞-缸套使用较多材料铸造铝合金(AlSi10Mg)进行3D打印,研究其摩擦磨损性能。在内燃机实际运行条件下活塞裙部通常会发生严重的摩擦和磨损。表面织构已成为现代减摩抗磨的有效方式之一,并成功应用于许多领域。利用3D打印技术加... 实验对活塞-缸套使用较多材料铸造铝合金(AlSi10Mg)进行3D打印,研究其摩擦磨损性能。在内燃机实际运行条件下活塞裙部通常会发生严重的摩擦和磨损。表面织构已成为现代减摩抗磨的有效方式之一,并成功应用于许多领域。利用3D打印技术加工出两种不同面积占有率楔形凹坑表面试样与光滑表面试样。在立式万能摩擦磨损试验机上进行销-盘回转实验,采用三维形貌仪、同轴显微镜以及扫描电子显微镜观察试样工作表面的磨损形貌。通过Fluent流体分析软件模拟仿真润滑油内部压力,并对仿真结果进行验证。研究结果表明,与光滑无织构试样对比,楔形织构试样对提升活塞裙部摩擦学性能起着积极的作用,且当织构面积占有率为7.01%时对减少摩擦系数降低磨损质量的效果更加显著,提升了活塞裙部的摩擦学性能。 展开更多
关键词 3D打印铸造铝合金 楔形织构 流体仿真分析 摩擦磨损
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How virtual reality can help visualise and assess geohazards 被引量:3
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作者 Hans-Balder Havenith Philippe Cerfontaine Anne-Sophie Mreyen 《International Journal of Digital Earth》 SCIE EI 2019年第2期173-189,共17页
Geohazard research requires extensive spatiotemporal understanding based on an adequate multi-scale representation of modelling results.The most commonly applied representation basis for collected data is still the on... Geohazard research requires extensive spatiotemporal understanding based on an adequate multi-scale representation of modelling results.The most commonly applied representation basis for collected data is still the one of a 2D plane,typically a map.Digital maps of spatial data can be visualised and processed by using Geographic Information Systems.It is far less common to use 3D geomodels for the analysis and visualisation of spatial data.For the visualisation of both spatial and temporal hazard components,there are no standardised tools.We claim that a full geohazard assessment is only possible inside a new type of geoscientific and technological environment that is at the same time multi-dimensional,spatiotemporal,integrated,fully interactive(tele-)immersive,and collaborative.Surface and subsurface processes are interacting at various scales that are difficult to be overviewed at once.Virtual Reality(VR)technology could provide an attractive solution to overcome the multi-dimensional and spatiotemporal obstacles.The review of geoscientific applications using VR technology developed by multiple teams around the world shows that some solutions have already been developed many years ago,but widespread use was not possible.This is clearly changing now and soon we will see if VR can contribute to a better understanding of geo-processes. 展开更多
关键词 4D geospace spatiotemporal analysis virtual environments immersive visualisation COLLABORATION
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Analysis of inborn errors of metabolism: disease spectrum for expanded newborn screening in Hong Kong 被引量:12
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作者 Han-Chih Hencher Lee Chloe Miu Mak +12 位作者 Ching-Wan Lam Yuet-Ping Yuen, Angel On-Kei Chan Chi-Chung Shek Tak-Shing Siu Chi-Kong Lai Chor-Kwan Ching Wai-Kwan Siu Sammy Pak-Lam Chen Chun-Yiu Law Morris Hok-Leung Tai Sidney Tam Albert Yan-Wo Chan 《Chinese Medical Journal》 SCIE CAS CSCD 2011年第7期983-989,共7页
Background Data of classical inborn errors of metabolism (IEM) of amino acids, organic acids and fatty acid oxidation are largely lacking in Hong Kong, where mass spectrometry-based expanded newborn screening for IE... Background Data of classical inborn errors of metabolism (IEM) of amino acids, organic acids and fatty acid oxidation are largely lacking in Hong Kong, where mass spectrometry-based expanded newborn screening for IEM has not been initiated. The current study aimed to evaluate the approximate incidence, spectrum and other characteristics of classical IEM in Hong Kong, which would be important in developing an expanded newborn screening program for the local area. 展开更多
关键词 biochemical genetics chemical pathology expanded newborn screening Hong Kong inborn errorsof metabolism tandem mass spectrometry
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PIWIL1 governs the crosstalk of cancer cell metabolism and immunosuppressive microenvironment in hepatocellular carcinoma 被引量:2
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作者 Ning Wang Hor-Yue Tan +8 位作者 Yuanjun Lu Yau-Tuen Chan Di Wang Wei Guo Yu Xu Cheng Zhang Feiyu Chen Guoyi Tang Yibin Feng 《Signal Transduction and Targeted Therapy》 SCIE CSCD 2021年第3期1033-1045,共13页
Altered energy metabolism of cancer cells shapes the immune cell response in the tumor microenvironment that faclitates tumorprogression.Herein,we reported the novel of tumor cell-expressed Piwi Like RNA-Mediated Gene... Altered energy metabolism of cancer cells shapes the immune cell response in the tumor microenvironment that faclitates tumorprogression.Herein,we reported the novel of tumor cell-expressed Piwi Like RNA-Mediated Gene Silencing 1(PWL1)in mediatingthe crosstlk of fatty acid metabolism and immune response of human hepatocellular carcinoma(HCC).PlWIL1 expression in HCCwas increased compared to normal hepatic tissues and was positively correlated with the proliferation rate of HCC cell ines.PIWL1overexpression accelerated in vitro proliferation and in vivo growth of HCC tumors,while PIWL1 knockdown showed opositeeffects.PIWL1 increased oxygen consumption and energy production via fatty acid metabolism without altering aerobic glycolysis.lnhibition of fatty acid metablism abolished PWIL1-induced HCC prolferation and growth.RNA-seq analysis revealed that immunesystem regulation might be involved,which was echoed by the experimental observation that PIWL1-overexpressing HCC cellsattracted myeloid-derived suppressor cells(MDSCs)into the tumor microenvironment.MDSCs depletion reduced the prolferationand growth of PlWIL1-overexpressing HCC tumors.Complement C3,whose secretion was induced by PIWL1 in HCC cells,mediatesthe interaction of HCC cells with MDSCs by activated p38 MAPK signaling in MDSCs,which in turn initiated expression of immunosuppressive cytokine L10.Neutralizing lL10 secretion reduced the immunosuppressive activity of MDSCs in the microenvironment of PIWL1-overexpressing HCC.Taken together,our study unraveled the critical role of PIWL1 in initiating theinteraction of cancer cell metabolism and immune cell response in HCC.Tumor cell-expressed PlIWL1 may be a potential target forthe devellopment of novel HCC treatment. 展开更多
关键词 METABOLISM MICROENVIRONMENT HEPATOCELLULAR
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Indications of pro-inflammatory cytokines in laparoscopic and open liver resection for early-stage hepatocellular carcinoma
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作者 Kevin Tak-Pan Ng Li Pang +5 位作者 Jia-Qi Wang Wong Hoi She Simon Hing-Yin Tsang Chung Mau Lo Kwan Man Tan To Cheung 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2024年第3期257-264,共8页
Background:Our clinical practice of laparoscopic liver resection(LLR)had achieved better short-term and long-term benefits for patients with hepatocellular carcinoma(HCC)over open liver resection(OLR),but the underlyi... Background:Our clinical practice of laparoscopic liver resection(LLR)had achieved better short-term and long-term benefits for patients with hepatocellular carcinoma(HCC)over open liver resection(OLR),but the underlying mechanisms are not clear.This study was to find out whether systemic inflammation plays an important role.Methods:A total of 103 patients with early-stage HCC under liver resection were enrolled(LLR group,n=53;OLR group,n=50).The expression of 9 inflammatory cytokines in patients at preoperation,postoperative day 1(POD1)and POD7 was quantified by Luminex Multiplex assay.The relationships of the cytokines and the postoperative outcomes were compared between LLR and OLR.Results:Seven of the circulating cytokines were found to be significantly upregulated on POD1 after LLR or OLR compared to their preoperative levels.Compared to OLR,the POD1 levels of granulocytemacrophage colony-stimulating factor(GM-CSF),interleukin-6(IL-6),IL-8,and monocyte chemoattractant protein-1(MCP-1)in the LLR group were significantly lower.Higher POD1 levels of these cytokines were significantly correlated with longer operative time and higher volume of blood loss during operation.The levels of these cytokines were positively associated with postoperative liver injury,and the length of hospital stay.Importantly,a high level of IL-6 at POD1 was a risk factor for HCC recurrence and poor disease-free survival after liver resection.Conclusions:Significantly lower level of GM-CSF,IL-6,IL-8,and MCP-1 after liver resection represented a milder systemic inflammation which might be an important mechanism to offer better short-term and long-term outcomes in LLR over OLR. 展开更多
关键词 Laparoscopic liver resection Open liver resection Hepatocellular carcinoma Postoperative cytokines Inflammatory responses
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