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Background : Breast cancer (BC) is the most common cancer in women all over the world and the second most common cause of cancer-related mortality. Imaging examination plays an important role in the diagnosis of early breast cancer. Due to different imaging principles and methods, all kinds of examinations have their advantages and disadvantages. It is particularly important for clinicians to choose these examination methods reasonably to achieve the best diagnostic effect. The objectives of this systematic review and NMA are to determine the diagnostic accuracy of imaging technologies for breast cancer and to compare the diagnostic accuracy of different index tests and to support guidelines development and clinical practice. Methods : PubMed, Embase.com, the Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science, China National Knowledge Infrastructure (CNKI), Wanfang, and SinoMed will be searched to identify relevant studies up to August 31, 2021. We will include random controlled trials, cross-sectional studies, case-control studies, and cohort studies that evaluate the diagnostic accuracy of different imaging diagnostic methods for breast cancer. The Quality Assessment of Diagnostic Accuracy Studies 2 quality assessment tool will be used to assess the risk of bias in each study. Standard pairwise meta-analysis and NMA will be performed using STATA V.12.0, MetaDiSc 1.40, and R 3.4.1 software to compare the diagnostic efficacy of different imaging diagnostic methods. Subgroup analyses and sensitivity analyses will be conducted to investigate the sources of heterogeneity. Results : The results of this study will be published in a peer-reviewed journal. Conclusion : This study will comprehensively evaluate the accuracy of different imaging diagnostic methods in the diagnosis of breast cancer. The results of this study will provide high-quality evidence to support clinical practice and guidelines development.

This paper reports the chemical identity and mechanism of action and formation of a cell growth inhibitory compound leached from some single-use Erlenmeyer polycarbonate shaker flasks under routine cell culture conditions. Single-use cell culture vessels have been increasingly used for the production of biopharmaceuticals; however, they often suffer from issues associated with leachables that may interfere with cell growth and protein stability. Here, high-performance liquid-chromatography preparations and cell proliferation assays led to identification of a compound from the water extracts of some polycarbonate flasks, which exhibited subline- and seeding density-dependent growth inhibition of CHO cells in suspension culture. Mass spectroscopy, nuclear magnetic resonance spectroscopy, and chemical synthesis confirmed that this compound is 3,5-dinitro-bisphenol A. Cell cycle analysis suggests that 3,5-dinitro-bisphenol A arrests CHO-S cells at the G1/Go phase. Dynamic mass redistribution assays showed tha...

Metabolism enzyme induction-mediated drug-drug interactions need to be carefully characterized in vitro for drug candidates to predict in vivo safety risk and therapeutic efficiency. Currently, both the Food and Drug Administration and European Medicines Agency recommend using primary human hepatocytes as the gold standard in vitro test system for studying the induction potential of candidate drugs on cytochrome P450 (CYP), CYP3A4, CYP1A2, and CYP2B6. However, primary human hepatocytes are known to bear inherent limitations such as limited supply and large lot-to-lot variations, which result in an experimental burden to qualify new lots. To overcome these shortcomings, a renewable source of human hepatocytes (i.e., Corning HepatoCells) was developed from primary human hepatocytes and was evaluated for in vitro CYP3A4 induction using methods well established by the pharmaceutical industry. HepatoCells have shown mature hepatocyte-like morphology and demonstrated primary hepatocyte-like response to prototypical inducers of all three CYP enzymes with excellent consistency. Importantly, HepatoCells retain a phenobarbital-responsive nuclear translocation of human constitutive androstane receptor from the cytoplasm, characteristic to primary hepatocytes. To validate HepatoCells as a useful tool to predict potential clinical relevant CYP3A4 induction, we tested three different lots of HepatoCells with a group of clinical strong, moderate/weak CYP3A4 inducers, and noninducers. A relative induction score calibration curve-based approach was used for prediction. HepatoCells showed accurate prediction comparable to primary human hepatocytes. Together, these results demonstrate that Corning HepatoCells is a reliable in vitro model for drug-drug interaction studies during the early phase of drug testing.

The ability to combine primary hit identification assays with target profiling would significantly streamline the current drug discovery process. Working towards this end, we report here the development of a microarray-based ligand binding assay that supports multiplexed analysis of G protein-coupled receptor systems in a 96-well microplate format that is compatible with the equipment and infrastructure typical of high-throughput screening laboratories. A prototype microarray was generated by pin-printing seven different receptors within the wells of a specially coated glass-bottom microplate and assaying with a cocktail of fluorescent ligands. Development of the multiplexed system included optimization of methods for depositing receptor membrane proteins and establishing a generic set of assay conditions that simultaneously satisfied the pharmacology requirements of all of the receptor systems included on the array. The multiplexed system is shown to produce valid pharmacological results as evidenced by its ability to report K(i) values for receptor-specific fluorescent ligands and rank ordered potencies for diagnostic displacing compounds comparable to values generated by conventional simplexed assays. Moreover, the results of a 40-compound mini-screen confirmed that the assay accurately identifies valid hits. The results suggest the assay may be immediately suitable for routine profiling tasks and demonstrate the potential of the format for high-throughput multiplexed drug discovery.

Multiplexing of G protein-coupled receptors (GPCRs) in microarrays promises to increase the efficiency, reduce the costs, and improve the quality of high-throughput assays. However, this technology is still nascent and has not yet achieved the status of "high throughput" or laid claim to handling a large set of receptors. In addition, the technology has been demonstrated only when using fluorescent ligands to detect binding, limiting its application to a subset of GPCRs. To expand the impact of multiplexing on this receptor class, we have developed a radiometric approach to the microarray assay. In these studies, we considered two receptors in the alpha-adrenergic receptor family, alpha2A and alpha2C, and the 125I-labeled agonist clonidine. We demonstrate that microarrays of these receptors can be readily detected (signal/noise ratio approximately 160) using a Typhoon 9210 PhosphorImager. In addition, biochemical characterization shows that ligand-binding profiles and selectivity are preserved with the selective antagonists BRL44408 and ARC239. Importantly, these microarrays use approximately 200- to 400-fold less membrane preparation required by conventional assay methods and allow two or more receptors to be assayed in an area equivalent to a standard well of a microtiter plate. The impact of this approach on screening in drug discovery is discussed.

The infection of human cells by HIV-1 virus can be mimicked by a fusion process between cells expressing the HIV envelope protein (Env) and cells expressing both human CD4 (huCD4) and appropriate human chemokine receptors. In this study, a macrophage-tropic (M-tropic) HIV cell-cell fusion assay was established that utilized huCD4, human CCR5 (huCCR5), and HIV ADAgpl60 as fusion components and a Gal4/VP16-activated luciferase as a reporter system. By combining CHO cells expressing huCD4 and huCCR5 with CHO cells expressing HIV ADAgpl60, a 300-fold increase in luciferase activity could be elicited relative to control. No luciferase activity was detected when HXB2gpl60 (T-tropic) was used instead of ADAgpl60 (M-tropic) as the fusion partner in the assay. Addition of anti-huCD4 (RPA-T4) or anti-huCCR5 (2D7) monoclonal antibodies in the assay significantly inhibited the fusion event; in contrast, an anti-CXCR4 (12G5) monoclonal antibody had little effect, indicating that the fusion assay was huCD4 and huCCR5 dependent. The cell-cell fusion occurred in a time-dependent manner; the maximum luciferase activity was detected about 8 hr after mixing the cells. The fusion events could also be monitored by another reporter system in which Gal4/VP16 activated green fluorescent protein (GFP) was used as the reporter instead of luciferase. In combination with fluorescence microscopy, the GFP reporter system allowed visualization of the fusion events in real time. Compared with previously described HIV fusion models, this system has several advantages, including simplicity, sensitivity, and the ability to allow continuous monitoring of the HIV cell-cell fusion event. Finally, this cell-cell fusion system is easily adapted to study other HIV fusion events.

This article describes a solvent treatment process for transforming standard flat polystyrene surfaces into textured microenvironments for three-dimensional (3D) cell culture. The process can be used with off-the-shelf microplates having 6, 12, 96, or even 384-well formats and completed in a few steps. The surface microtexture resembles tightly packed, non-interconnected micropores having a median pore size of either 115 or 19 μm depending on the strength of the solvent mixture. Hansen solubility parameter analysis was used to map out the polymer–solvent interaction conditions necessary for creating the surface texture. Primary human hepatocytes cultured on two-dimensional control surfaces attached with a flat monolayer morphology while those cultured on surfaces having 115 μm-sized pores exhibited a round 3D morphology. The cells also showed more in-vivo like behavior on the porous surface by exhibiting significantly higher basal enzymatic activity and expressing higher levels of several drug metabolism-related genes. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40181.

Current status of mobile application testing is commonly used artificial test. In order to reduce the test costs and improve the availability and system stability of the android mobile applications, through an activity page based model to optimize the page crawling algorithm to generate a test case sequence, combined with some open source tools and frameworks, this paper proposed a low cost practical functional test automation for Android applications.

Conventional assay methods for discovering and profiling drug-target interactions are typically developed on a target-bytarget basis and hence can be cumbersome to enable and orchestrate. Herein the authors report a solid-state ligand-binding assay that operates in a multiplexed mode to report compound activity against a micorarray-configured panel of G-proteincoupled receptor (GPCR) targets. The pharmacological fidelity of the system is high, and its miniaturized “plug-and-play” format provides improved efficiency both in terms of execution time and reagent consumption. Taken together, these features make the system ideally suited to explore the structure-activity relationship of compounds across a broad region of target class space.(Journal of Biolmolecular Screening 2006:435-438)

The increased number of drug targets and compounds demands novel high-throughput screening technologies that could be used for parallel analysis of many genes and proteins. Protein microarrays are evolving promising technologies for the parallel analysis of many proteins with respect to their abundance, location, modifications, and interactions with other biological and chemical molecules. This chapter specifically describes the fabrication of G protein-coupled receptor (GPCR) microarrays, a unique subset of protein microarrays, using contact-pin printing technology. The bioassays and potential applications of GPCR microarrays for the determination of compound affinities and potencies are also included.

The increased number of drug targets and compounds demands novel high-throughput screening technologies that could be used for parallel analysis of many genes and proteins. Protein microarrays are evolving promising technologies for the parallel analysis of many proteins with respect to their abundance, location, modifications, and interactions with other biological and chemical molecules. This chapter specifically describes the fabrication of G protein-coupled receptor (GPCR) microarrays, a unique subset of protein microarrays, using contact-pin printing technology. The bioassays and potential applications of GPCR microarrays for the determination of compound affinities and potencies are also included.

The possibility of using microarray technology for mechanistic understanding of drug toxicity has opened up a new research field in Toxicology. In an attempt to build knowledge in the field, we have designed a 1C-gene array composed of 85 known human genes with toxicological interests and 15 control genes. HepG2 cells were treated with ethanol and two anticancer drugs, mitomycin C and doxorubicin. RNA were isolated and labeled by fluorescent dyes, then hybridized to the 1C-gene array. Our results showed that a number of cytochrome P450 genes, such as CYP4F2/3, CYP3A3, CYP24, and CYP51, were consistently responsive to the toxicant treatment. However, different genes response to different toxicants. For example, CYP24 and CYP51 were up regulated by the ethanol treatment but remained unresponsive to the other two drugs. The anticancer drugs, but not ethanol differentially regulated several other genes including CYP3A3, TNFRSF6 and CHES1, implying that the two drugs might function through a similar mechanism, which differs from that of ethanol. The reproducibility of our results suggests that microarray- based expression analysis may offer a rapid and efficient means of assessing drug toxicity.

This paper describes G-protein-coupled receptor (GPCR) microarrays on porous glass substrates and functional assays based on the binding of a europium-labeled GTP analogue. The porous glass slides were made by casting a glass frit on impermeable glass slides and then coating with gamma-aminopropyl silane (GAPS). The emitted fluorescence was captured on an imager with a time-gated intensified CCD detector. Microarrays of the neurotensin receptor 1, the cholinergic receptor muscarinic 2, the opioid receptor mu, and the cannabinoid receptor 1 were fabricated by pin printing. The selective agonism of each of the receptors was observed. The screening of potential antagonists was demonstrated using a cocktail of agonists. The amount of activation observed was sufficient to permit determinations of EC50 and IC50. Such microarrays could potentially streamline drug discovery by helping integrate primary screening with selectivity and safety screening without compromising the essential functional information obtainable from cellular assays.