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Hemoglobin induces colon cancer cell proliferation by release of reactive oxygen species

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World Journal of Gastroenterology 2006年第35期12卷 5644-5650页

作者： Ryung-ah Lee Hyun-ah Kim Bo-Young Kang Kwang-Ho Kim Ewha Medical Institute Department of Surgery College of Medicine Ewha Womans University Seoul Korea Department of Surgery College of Medicine Ewha Womans University Seoul Korea Ewha Medical Institute Ewha Womans University Seoul Korea

AIM: To study whether hemoglobin could amplify colon cancer cell proliferation via reactive oxygen species (ROS) production. METHODS: Colon cancer cell line HT-29 was grown in the conventional method using RPMI1640 media. The viability of the cells was measured using the colorimetric MTT [3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazo- lium bromide] assay after adding hemoglobin. We de- termined reactive oxygen species levels to be indicators of oxidative stress in HT 29 cell lines with and without hemoglobin and/or 5-fluorouracil (5-FU), 5’-deoxy-5-flu- orouridine (5-DFUR) using fluorometric dichlorofluorescin diacetate (DCFH-DA) assay. RESULTS: Cellular proliferation was increased with he- moglobin in a concentration-dependent manner. A signif- icant increment on ROS levels was found in HT 29 cells following hemoglobin incubation. The cytotoxic effects of 5-FU and 5-DFUR were significantly blunted by admin- istration of hemoglobin. There was a slight increase of peroxiredoxin 1, superoxide dismutase 1 concentration according to different hemoglobin concentrations. CONCLUSION: Hemoglobin has a cellular proliferative effect on HT-29 colon cancer cell line by production of ROS. Also, hemoglobin abates cytotoxic effects of che- motherapeutic agents such as 5-FU and 5-DFUR.

关键词： Colon cancer Hemoglobin Reactive oxygen species

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基于卷积神经网络的手势识别算法设计

蚌埠学院学报 2024年第2期13卷 71-76页

作者：李银银陈磊杨罡赵静淮南师范学院计算机学院安徽淮南232038 淮南师范学院化学与材料工程学院安徽淮南232038

针对传感器对手势识别存在范围小、鲁棒性弱等痛点,采用MediaPipe机器学习框架对捕获的手势图像实时遍历,利用卷积神经网络进行高斯平滑滤波,并结合21个特征关节点手掌模型,根据欧氏空间距离判别阈值和单个手指曲率对指间动作做出分类,... 详细信息

针对传感器对手势识别存在范围小、鲁棒性弱等痛点,采用MediaPipe机器学习框架对捕获的手势图像实时遍历,利用卷积神经网络进行高斯平滑滤波,并结合21个特征关节点手掌模型,根据欧氏空间距离判别阈值和单个手指曲率对指间动作做出分类,通过坐标关系建立指尖和模型特征点之间的实时映射。经测试,目标区域内手势识别准确精度达到98%,并实现了对控制音量大小等操作类手势的准确识别。

关键词：人机交互手势识别卷积神经网络

Development of hyaluronic acid-based edible film for alleviating dry mouth

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Food Science and Human Wellness 2023年第2期12卷 371-377页

作者： Dong-Keon Kweon Jung-ah Han Jinwoo Bio Co. Ltd.Yongin 17111Korea Department of Food and Nutrition Sangmyung UniversitySeoul 03016Korea

For alleviating dry mouth symptoms,edible films based on hyaluronic acid(HA)with 3 different m(800,1200 and 2300 kDa)were prepared(800 F,1200 F and 2300 F,respectively),and the properties as well as effectiveness were *** concentration of each HA dispersion for film forming was set as 3.0%,1.5%or 1.0%,for the m800,1200 and 2300 kDa,respectively,based on the *** 800 F showed the highest thickness,tensile strength,and water vapor transparency,whereas obtained the lowest transparency and elongation at break among *** of the HA films showed safety against microorganism during 28 storage day at 40℃with 60%*** optimum site for film attachment in mouth was the palate,and800 F was the most effective for stimulating saliva secretion,eliciting a 38%increase compared to control(without film),tested by the elderly over 65 years *** the sensory test,800 F was also the most *** on above results,the edible films effectively stimulating saliva secretion could be produced with HA,and the physical,sensory characteristics as well as disintegration times of the film could be controlled by mand the dissolution concentration of HA.

关键词： Edible film Hyaluronic acid Saliva stimulating Tensile strength Thickness

Digital exchange attributes and the risk of closure

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Blockchain(Research and Applications) 2023年第2期4卷 136-145页

作者： Seung ah Lee George Milunovich Department of Actuarial Studies and Business Analytics Macquarie UniversitySydneyNSW2109Australia

Presently,there are over 500 cryptocurrency exchanges worldwide and more than 19,700 different *** the fact that cryptocurrency trading is possible via private peer-to-peer transactions,more than 90%of trading occurs on organised exchanges,which provide convenience and ***,centralised cryptocurrency exchanges are regarded as high-value targets by criminals and are often victims of *** this paper,we investigate the risk of cryptocurrency exchange closures and develop predictive models to forecast which markets will close down and which ones will remain active using publicly available *** models perform well and reach a high level of classification *** trading volume,the availability of public information on exchange staff,exchange lifetime,and several cybersecurity features are identified as key attributes in predicting exchange ***,our models do not account for all sources of risk,e.g.,potential fraud and mismanagement of client funds committed by the exchanges themselves,and market participants are encouraged to carefully consider where and how they store their digital assets.

关键词： Cryptocurrency markets Digital exchange Closure Classification Predictive models

Natural dietary anti-cancer chemopreventive compounds:redox-mediated differential signaling mechanisms in cytoprotection of normal cells versus cytotoxicity in tumor cells

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Acta Pharmacologica Sinica 2007年第4期28卷 459-472页

作者： Sujit NAIR ah-Ng Tony KONG Graduate Program in Pharmaceutical Sciences Department of Pharmaceutics Ernest Mario School of PharmacyRutgersThe StateUniversity of New JerseyPiscatawayNew Jersey 08854USA

Many dietary phytochemicals exhibit health-beneficial effects including preven-tion of diseases such as cancer,as well as neurological,cardiovascular,inflam-matory,and metabolic ***,herbivorous and omnivorousanimals have been ingesting *** interaction between"animal-plant"ecosystems has resulted in an elaborate system of detoxification and defensemechanisms evolved by animals including *** cells,includinghuman cells,respond to these dietary phytochemicals by"non-classical receptorsensing"mechanisms of electrophilic chemical-stress typified by"thiol-modu-lated"cellular signaling events primarily leading to the gene expression of phar-macologically beneficial effects,but sometimes unwanted cytotoxicity *** has been studying two groups of dietary phytochemical cancer-chemopreventive compounds (isothiocyanates and polyphenols),which areeffective in chemical-induced,as well as genetically-induced,animal carcinogen-esis *** compounds typically generate"cellular stress"and modulategene expression of phase Ⅱ detoxifying/antioxidant ***,reac-tive oxygen species,and reactive nitrogen species are known to act as secondmessengers in the modulation of many cellular signaling pathways leading togene expression changes and pharmacological ***-sensitive tran-scription factors such as nuclear factor-E2-related factor 2 (Nrf2),AP-1,NF-κB,tocite a few examples,sense and transduce changes in the cellular redox status andmodulate gene expression responses to oxidative and electrophilic stresses,pre-sumably via sulfhydryl modification of critical cysteine residues found on theseproteins and/or other upstream redox-sensitive molecular *** the currentreview,we will explore dietary cancer chemopreventive phytochemicals,discussthe link between oxidative/electrophilic stresses and the redox circuitry,and con-sider different redox-sensitive transcription *** will also discuss thekelch-l

关键词： redox Nrf2 Keapl NES NLS gene expression profiles

碳限额及碳交易机制下低碳供应链合作促销与减排研究

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物流科技 2024年第7期47卷 1-7页

作者：邵灵芝尹丽安徽工业大学管理科学与工程学院安徽马鞍山243032

构建Stackelberg博弈模型,在碳限额及碳交易机制下,考虑由单一制造商和零售商组成的两级供应链,通过制造商和供应链成员之间的合作,来探讨减排与促销策略问题。分析了零售商制造商独自承担各自费用、合作促销和合作减排等情形下供应链... 详细信息

构建Stackelberg博弈模型,在碳限额及碳交易机制下,考虑由单一制造商和零售商组成的两级供应链,通过制造商和供应链成员之间的合作,来探讨减排与促销策略问题。分析了零售商制造商独自承担各自费用、合作促销和合作减排等情形下供应链成员最优决策。并通过算例分析研究发现:合作促销与合作减排成本分担比例在满足一定条件时都优于独自促销和减排,因此,碳排放依赖较大的行业可以选取合作减排模式,依赖销售努力较大的行业可以选取合作促销模式。

关键词：碳限额与碳交易低碳供应链 Stackelberg博弈合作减排合作促销

聚氯乙烯/热塑性聚氨酯共混合金的静动态力学性能及微观结构分析

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材料导报 2024年第19期38卷 264-269页

作者：雷经发沈强刘涛孙虹尹志强安徽建筑大学机械与电气工程学院合肥230601 工程机械智能制造安徽省教育厅重点实验室合肥230601 灾害环境人员安全安徽省重点实验室合肥230601

为了揭示聚氯乙烯(PVC)/热塑性聚氨酯(TPU)共混合金的静动态力学性能以及微观结构对共混体系力学性能的影响,采用万能材料试验机和分离式霍普金森压杆(SHPB)实验装置对PVC/TPU合金开展准静态、动态力学性能实验,获取了较宽应变率范围(0.... 详细信息

为了揭示聚氯乙烯(PVC)/热塑性聚氨酯(TPU)共混合金的静动态力学性能以及微观结构对共混体系力学性能的影响,采用万能材料试验机和分离式霍普金森压杆(SHPB)实验装置对PVC/TPU合金开展准静态、动态力学性能实验,获取了较宽应变率范围(0.001~5800 s^(-1))内的应力-应变曲线,并通过傅里叶变换红外光谱(FTIR)及扫描电镜(SEM)对PVC/TPU合金微观结构进行表征。结果表明,材料在准静态拉伸及动态压缩下均具有显著的应变率强化效应。共混比会影响其微观结构及力学性能,共混比为90/10(PVC/TPU)时,材料弹性模量、峰值应力及断裂伸长率最高,且两相相容性最好;随着TPU占比增加,材料的拉伸与压缩力学性能下降,两相之间出现明显的界面层;此外,共混比为50/50时,材料相结构较为复杂,出现双连续相与“海-岛”结构共存的复杂形貌。

关键词：共混合金力学性能应变率微观形貌

Studies on the flow and distribution of leukocytes in mesentery microcirculation of rats

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World Journal of Gastroenterology 1999年第3期5卷 231-234页

作者： Jiang Y Liu ah Zhao KS Mil Med Univ 1st Chinese PLA Lab Shock & Microcirculat Guangzhou 510515 Peoples R China

AIM To study the effect of leukocyteendothelium interaction (LEI) on the flow anddistribution of leukocytes in microcirculationunder physiological *** A microcirculation image multipleparameter computer analysis system (MIMPCAS)was used to study the flow and distribution ofleukocytes in mesentery microcirculation of ratsIn *** The difference of visible leukocyteflux (VLF) was as high as 131 times in thearterioles and venules with similar diameter andblood velocity. The visible leukocytes rolledalong the blood vessel wall as a" jerky"movement. The frequency distribution of thevisible leukocyte velocity (VLV) showed a "twopeak" Curve. The low peak value was at 10 pm/ s-- 15 pm/ s while the high peak fell between25 pm/ s-- 30 pm/ s. With the increase of diameterof venules, VLF increased while the VLVremained at the same level. With the increase ofRBC velocity, VLV trends to elevate and VLF tofal I *** The results herein might providea basic theory for the study on the mechanism ofLEI under physiological condition and novelmethods for the prevention and treatment of highLEI in many pathological

关键词： Studies on the flow and distribution of leukocytes in mesentery microcirculation of rats flow

The anti-tubercular activity of Melia azedarach L. and Lobelia chinensis Lour. and their potential as effective anti-Mycobacterium tuberculosis candidate agents

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Asian Pacific Journal of Tropical Biomedicine 2016年第10期6卷 830-835页

作者： Won Hyung Choi In ah Lee Department of Biomedical Science School of Medicine Kyung Hee University Department of Medical Zoology School of Medicine Kyung Hee University Department of Chemistry College of Natural Science Kunsan National University

Objective: To evaluate the anti-mycobacterial activity of Melia azedarach L.(M. azedarach) and Lobelia chinensis Lour.(L. chinensis) extracts against the growth of Mycobacterium tuberculosis(M. tuberculosis).Methods: The anti-M. tuberculosis activity of M. azedarach and L. chinensis extracts were evaluated using different indicator methods such as resazurin microtiter assay(REMA) and mycobacteria growth indicator tube(MGIT) 960 system assay. The M. tuberculosis was incubated with various concentrations(50–800 mg/m L) of the extracts for 5 days in the REMA, and for 4 weeks in MGIT 960 system ***: M. azedarach and L. chinensis extracts showed their anti-M. tuberculosis activity by strongly inhibiting the growth of M. tuberculosis in a concentration-dependent manner in the REMA and the MGIT 960 system assay. Particularly, the methanol extract of M. azedarach and n-hexane extract of L. chinensis consistently exhibited their effects by effectively inhibiting the growth of M. tuberculosis in MGIT 960 system for 4 weeks with a single-treatment, indicating higher anti-M. tuberculosis activity than other extracts,and their minimum inhibitory concentrations were measured as 400 mg/m L and 800 mg/m L, ***: These results demonstrate that M. azedarach and L. chinensis extracts not only have unique anti-M. tuberculosis activity, but also induce the selective antiM. tuberculosis effects by consistently inhibiting or blocking the growth of M. tuberculosis through a new pharmacological action. Therefore, this study suggests the potential of them as effective candidate agents of next-generation for developing a new anti-tuberculosis drug, as well as the advantage for utilizing traditional medicinal plants as one of effective strategies against tuberculosis.

关键词： Lobelia chinensis Lour. Melia azedarach L. MGIT 960 system Drug susceptibility Tuberculosis