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  1. Article ; Online: Development of a human liver microphysiological co-culture system for higher throughput chemical safety assessment.

    Ip, Blanche C / Madnick, Samantha J / Zheng, Sophia / van Tongeren, Tessa C A / Hall, Susan J / Li, Hui / Martin, Suzanne / Spriggs, Sandrine / Carmichael, Paul / Chen, Wei / Ames, David / Breitweiser, Lori A / Pence, Heather E / Bowling, Andrew J / Johnson, Kamin J / Cubberley, Richard / Morgan, Jeffrey R / Boekelheide, Kim

    Toxicological sciences : an official journal of the Society of Toxicology

    2024  

    Abstract: Chemicals in the systemic circulation can undergo hepatic xenobiotic metabolism, generate metabolites and exhibit altered toxicity compared to their parent compounds. This paper describes a two-chamber liver-organ co-culture model in a higher-throughput ... ...

    Abstract Chemicals in the systemic circulation can undergo hepatic xenobiotic metabolism, generate metabolites and exhibit altered toxicity compared to their parent compounds. This paper describes a two-chamber liver-organ co-culture model in a higher-throughput 96-well format for the determination of toxicity on target tissues in the presence of physiologically relevant human liver metabolism. This two-chamber system is a hydrogel formed within each well consisting of a central well (target tissue) and an outer ring-shaped trough (human liver tissue). The target tissue chamber can be configured to accommodate a three-dimensional (3D) spheroid-shaped microtissue, or a two-dimensional (2D) cell mono-layer. Culture medium and compounds freely diffuse between the two chambers. Human differentiated HepaRGTM liver cells are used to form the 3D human liver microtissues, which displayed robust protein expression of liver biomarkers (albumin, asialoglycoprotein receptor, Phase I cytochrome P450 (CYP3A4) enzyme, multidrug resistance-associated protein 2 transporter, and glycogen), and exhibited Phase I/II enzyme activities over the course of 17 days. Histological and ultrastructural analyses confirmed that the HepaRG microtissues presented a differentiated hepatocyte phenotype, including abundant mitochondria, endoplasmic reticulum and bile canaliculi. Liver microtissue zonation characteristics could be easily modulated by maturation in different media supplements. Furthermore, our proof-of-concept study demonstrated the efficacy of this co-culture model in evaluating testosterone-mediated androgen receptor responses in the presence of human liver metabolism. This liver-organ co-culture system provides a practical, higher-throughput testing platform for metabolism-dependent bioactivity assessment of drugs/chemicals, to better recapitulate the biological effects and potential toxicity of human exposures.
    Language English
    Publishing date 2024-02-09
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1420885-4
    ISSN 1096-0929 ; 1096-6080
    ISSN (online) 1096-0929
    ISSN 1096-6080
    DOI 10.1093/toxsci/kfae018
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Book ; Online: Developing a Machine-Learning Algorithm to Diagnose Age-Related Macular Degeneration

    Dua, Ananya / Minh, Pham Hung / Fahmid, Sajid / Gupta, Shikhar / Zheng, Sophia / Moyo, Vanessa / Xue, Yanran Elisa

    2022  

    Abstract: Today, more than 12 million people over the age of 40 suffer from ocular diseases. Most commonly, older patients are susceptible to age related macular degeneration, an eye disease that causes blurring of the central vision due to the deterioration of ... ...

    Abstract Today, more than 12 million people over the age of 40 suffer from ocular diseases. Most commonly, older patients are susceptible to age related macular degeneration, an eye disease that causes blurring of the central vision due to the deterioration of the retina. The former can only be detected through complex and expensive imaging software, markedly a visual field test; this leaves a significant population with untreated eye disease and holds them at risk for complete vision loss. The use of machine learning algorithms has been proposed for treating eye disease. However, the development of these models is limited by a lack of understanding regarding appropriate model and training parameters to maximize model performance. In our study, we address these points by generating 6 models, each with a learning rate of 1 * 10^n where n is 0, -1, -2, . -6, and calculated a f1 score for each of the models. Our analysis shows that sample imbalance is a key challenge in training of machine learning models and can result in deceptive improvements in training cost which does not translate to true improvements in model predictive performance. Considering the wide ranging impact of the disease and its adverse effects, we developed a machine learning algorithm to treat the same. We trained our model on varying eye disease datasets consisting of over 5000 patients, and the pictures of their infected eyes. In the future, we hope this model is used extensively, especially in areas that are under-resourced, to better diagnose eye disease and improve well being for humanity.

    Comment: 7 pages, 7 figures
    Keywords Electrical Engineering and Systems Science - Image and Video Processing ; Computer Science - Computer Vision and Pattern Recognition ; Computer Science - Machine Learning
    Subject code 006
    Publishing date 2022-01-28
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Book ; Thesis: Electronic consumer contracts in the conflict of laws

    Tang, Zheng Sophia

    (Studies in private international law ; 1)

    2009  

    Author's details Zheng Sophia Tang
    Series title Studies in private international law ; 1
    Keywords Conflict of laws/Contracts ; Consumer protection/Law and legislation ; Electronic commerce/Law and legislation ; Electronic contracts ; Jurisdiction
    Language English
    Size XXIX, 317 S
    Publisher Hart
    Publishing place Oxford u.a.
    Document type Book ; Thesis
    Thesis / German Habilitation thesis Univ., Diss.--Birmingham, 2007
    ISBN 9781841138473 ; 1841138479
    Database Former special subject collection: coastal and deep sea fishing

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  4. Article ; Online: Multiplex quantitative detection of SARS-CoV-2 specific IgG and IgM antibodies based on DNA-assisted nanopore sensing.

    Zhang, Zehui / Wang, Xiaoqin / Wei, Xiaojun / Zheng, Sophia W / Lenhart, Brian J / Xu, Peisheng / Li, Jie / Pan, Jing / Albrecht, Helmut / Liu, Chang

    Biosensors & bioelectronics

    2021  Volume 181, Page(s) 113134

    Abstract: The coronavirus disease (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread into a global pandemic. Early and accurate diagnosis and quarantine remain the most effective mitigation strategy. Although reverse ... ...

    Abstract The coronavirus disease (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread into a global pandemic. Early and accurate diagnosis and quarantine remain the most effective mitigation strategy. Although reverse transcriptase polymerase chain reaction (RT-qPCR) is the gold standard for COVID-19 diagnosis, recent studies suggest that nucleic acids were undetectable in a significant number of cases with clinical features of COVID-19. Serologic assays that detect human antibodies to SARS-CoV-2 serve as a complementary method to diagnose these cases, as well as to identify asymptomatic cases and qualified convalescent serum donors. However, commercially available enzyme-linked immunosorbent assays (ELISA) are laborious and non-quantitative, while point-of-care assays suffer from low detection accuracy. To provide a serologic assay with high performance and portability for potential point-of-care applications, we developed DNA-assisted nanopore sensing for quantification of SARS-CoV-2 related antibodies in human serum. Different DNA structures were used as detection reporters for multiplex quantification of immunoglobulin M (IgM) and immunoglobulin G (IgG) antibodies against the nucleocapsid protein of SARS-CoV-2 in serum specimens from patients with conformed or suspected infection. Comparing to a clinically used point-of-care assay and an ELISA assay, our technology can reliably quantify SARS-CoV-2 antibodies with higher accuracy, large dynamic range, and potential for assay automation.
    MeSH term(s) Antibodies, Viral/analysis ; Biosensing Techniques ; COVID-19/diagnosis ; COVID-19 Testing/methods ; DNA ; Enzyme-Linked Immunosorbent Assay ; Humans ; Immunoglobulin G/analysis ; Immunoglobulin M/analysis ; Nanopores ; SARS-CoV-2 ; Sensitivity and Specificity
    Chemical Substances Antibodies, Viral ; Immunoglobulin G ; Immunoglobulin M ; DNA (9007-49-2)
    Language English
    Publishing date 2021-03-03
    Publishing country England
    Document type Journal Article
    ZDB-ID 1011023-9
    ISSN 1873-4235 ; 0956-5663
    ISSN (online) 1873-4235
    ISSN 0956-5663
    DOI 10.1016/j.bios.2021.113134
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Development of a human liver microphysiological coculture system for higher throughput chemical safety assessment

    Ip, Blanche C. / Madnick, Samantha J. / Zheng, Sophia / van Tongeren, Tessa C.A. / Hall, Susan J. / Li, Hui / Martin, Suzanne / Spriggs, Sandrine / Carmichael, Paul / Chen, Wei / Ames, David / Breitweiser, Lori A. / Pence, Heather E. / Bowling, Andrew J. / Johnson, Kamin J. / Cubberley, Richard / Morgan, Jeffrey R. / Boekelheide, Kim

    Toxicological sciences (2024) ; ISSN: 1096-6080

    2024  

    Abstract: Chemicals in the systemic circulation can undergo hepatic xenobiotic metabolism, generate metabolites, and exhibit altered toxicity compared with their parent compounds. This article describes a 2-chamber liver-organ coculture model in a higher- ... ...

    Abstract Chemicals in the systemic circulation can undergo hepatic xenobiotic metabolism, generate metabolites, and exhibit altered toxicity compared with their parent compounds. This article describes a 2-chamber liver-organ coculture model in a higher-throughput 96-well format for the determination of toxicity on target tissues in the presence of physiologically relevant human liver metabolism. This 2-chamber system is a hydrogel formed within each well consisting of a central well (target tissue) and an outer ring-shaped trough (human liver tissue). The target tissue chamber can be configured to accommodate a three-dimensional (3D) spheroid-shaped microtissue, or a 2-dimensional (2D) cell monolayer. Culture medium and compounds freely diffuse between the 2 chambers. Human-differentiated HepaRG liver cells are used to form the 3D human liver microtissues, which displayed robust protein expression of liver biomarkers (albumin, asialoglycoprotein receptor, Phase I cytochrome P450 [CYP3A4] enzyme, multidrug resistance-associated protein 2 transporter, and glycogen), and exhibited Phase I/II enzyme activities over the course of 17 days. Histological and ultrastructural analyses confirmed that the HepaRG microtissues presented a differentiated hepatocyte phenotype, including abundant mitochondria, endoplasmic reticulum, and bile canaliculi. Liver microtissue zonation characteristics could be easily modulated by maturation in different media supplements. Furthermore, our proof-of-concept study demonstrated the efficacy of this coculture model in evaluating testosterone-mediated androgen receptor responses in the presence of human liver metabolism. This liver-organ coculture system provides a practical, higher-throughput testing platform for metabolism-dependent bioactivity assessment of drugs/chemicals to better recapitulate the biological effects and potential toxicity of human exposures.
    Keywords Life Science
    Subject code 500
    Language English
    Publishing country nl
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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