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Multiple Chemical Sensitivities

Shengwu Yuan, Chao Huang, Xiaoya Ji, Mei Ma, Kaifeng Rao, Zijian Wang
The environmental risks of environmental estrogens (EEs) are often assessed via the same mode of action in the concentration addition (CA) model, neglecting the complex combined mechanisms at the genetic level. In this study, the cell proliferation effects of estrone, 17α-ethinylestradiol, 17β-estradiol, estriol, diethylstilbestrol, estradiol valerate, bisphenol A, 4-tert-octylphenol and 4-nonylphenol were determined individually using the CCK-8 method, and the proliferation effects of a multicomponent mixture of estrogenic chemicals mixed at equipotent concentrations using a fixed-ratio design were studied using estrogen-sensitive MCF-7 cells...
May 18, 2018: Ecotoxicology and Environmental Safety
Shashank Gorityala, Shuming Yang, Monica M Montano, Yan Xu
Androgens play a vital role in prostate cancer development, and their elimination and blockade are essential in the disease management. DHT is the key ligand for androgen receptor (AR) in the prostate. It is locally synthesized from testosterone. In the prostate, DHT is predominantly metabolized to α-diol and β-diol. Recent studies indicate that impaired DHT catabolism is associated with prostate cancer, signifying the necessity of a sensitive quantitative method for the determination of DHT and its metabolites...
May 16, 2018: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
Marzena Matejczyk, Grzegorz Świderski, Renata Świsłocka, Stanisław Józef Rosochacki, Włodzimierz Lewandowski
The most important problems of anti-cancer therapy include the toxicity of the drugs applied to healthy cells and the multi-drug cells resistance to chemotherapeutics. One of the most commonly used anticancer drugs is doxorubicin (DOX) used to treat certain leukemias and non-Hodgkin's lymphomas, as well as bladder, breast, stomach, lung, ovarian, thyroid, multiple myeloma and other cancers. Preliminary studies showed that metal complex with DOX improve its cytostatic activity with changes in their molecular structure and distribution of electrons, resulting in a substantial change of its biological activity (including antitumor activity)...
July 2018: Journal of Trace Elements in Medicine and Biology
Chin-Wei Huang, Kao-Min Lin, Te-Yu Hung, Yao-Chung Chuang, Sheng-Nan Wu
BACKGROUND/AIMS: Rotenone (Rot) is known to suppress the activity of complex I in the mitochondrial chain reaction; however, whether this compound has effects on ion currents in neurons remains largely unexplored. METHODS: With the aid of patch-clamp technology and simulation modeling, the effects of Rot on membrane ion currents present in mHippoE-14 cells were investigated. RESULTS: Addition of Rot produced an inhibitory action on the peak amplitude of INa with an IC50 value of 39...
May 11, 2018: Cellular Physiology and Biochemistry
Lidija Brkljačić, Ivanka Jerić
Chemical derivatization of carbonyl compounds is a prerequisite for their determination in environmental and biological samples by LC-MS/MS analysis. The main requirements in regard to the good derivatization reagent are fast, selective and quantitative reaction with carbonyl compounds, and efficient fragmentation upon collision-induced dissociation (CID). We have prepared glutamic acid-related hydrazine reagent, and optimized derivatization procedure with benzaldehyde as a model carbonyl compound. The CID spectrum of the obtained hydrazone gave rich fragmentation pattern with numerous abundant fragment ions...
May 15, 2018: Journal of Mass Spectrometry: JMS
Long Yuan, Shenita Basdeo, Qin C Ji
BMS-986104 is a S1P1 R modulator drug candidate under development and has been evaluated in Phase I clinical trials. BMS-986104 functions as a prodrug and undergoes enzymatic transformations in vivo to form the pharmacologically active phosphate drug, BMS-986104-P. Here, we report approaches to overcome the stability, solubility and extraction challenges in developing a sensitive, accurate and rugged LC-MS/MS method for the simultaneous quantification of the phosphate drug and its prodrug in blood lysate. An effective stabilization strategy using a cocktail of phosphatase and kinase inhibitors was developed to ensure the stability of both analytes during sample collection, storage, and processing...
May 5, 2018: Journal of Pharmaceutical and Biomedical Analysis
Michael Z Kamrath, Thomas R Rizzo
Ion mobility spectrometry (IMS) has become a valuable tool in biophysical and bioanalytical chemistry because of its ability to separate and characterize the structure of gas-phase biomolecular ions on the basis of their collisional cross section (CCS). Its importance has grown with the realization that in many cases, biomolecular ions retain important structural characteristics when produced in the gas phase by electrospray ionization (ESI). While a CCS can help distinguish between structures of radically different types, one cannot expect a single number to differentiate similar conformations of a complex molecule...
May 10, 2018: Accounts of Chemical Research
Tara J Thrupp, Tamsin J Runnalls, Martin Scholze, Subramaniam Kugathas, Andreas Kortenkamp, John P Sumpter
Ill-defined, multi-component mixtures of steroidal pharmaceuticals are present in the aquatic environment. Fish are extremely sensitive to some of these steroids. It is important to know how fish respond to these mixtures, and from that knowledge develop methodology that enables accurate prediction of those responses. To provide some of the data required to reach this objective, pairs of fish were first exposed to five different synthetic steroidal pharmaceuticals (one estrogen, EE2; one androgen, trenbolone; one glucocorticoid, beclomethasone dipropionate; and two progestogens, desogestrel and levonorgestrel) and concentration-response data on egg production obtained...
April 1, 2018: Science of the Total Environment
Jinpeng Wu, Shawn Sallis, Ruimin Qiao, Qinghao Li, Zengqing Zhuo, Kehua Dai, Zixuan Guo, Wanli Yang
Energy storage has become more and more a limiting factor of today's sustainable energy applications, including electric vehicles and green electric grid based on volatile solar and wind sources. The pressing demand of developing high-performance electrochemical energy storage solutions, i.e., batteries, relies on both fundamental understanding and practical developments from both the academy and industry. The formidable challenge of developing successful battery technology stems from the different requirements for different energy-storage applications...
April 17, 2018: Journal of Visualized Experiments: JoVE
Frances Xin, Lauren M Smith, Martha Susiarjo, Marisa S Bartolomei, Karl J Jepsen
Early life exposures to endocrine-disrupting chemicals (EDCs) have been associated with physiological changes of endocrine-sensitive tissues throughout postnatal life. Although hormones play a critical role in skeletal growth and maintenance, the effects of prenatal EDC exposure on adult bone health are not well understood. Moreover, studies assessing skeletal changes across multiple generations are limited. In this article, we present previously unpublished data demonstrating dose-, sex-, and generation-specific changes in bone morphology and function in adult mice developmentally exposed to the model estrogenic EDC bisphenol A (BPA) at doses of 10 μg (lower dose) or 10 mg per kg bw/d (upper dose) throughout gestation and lactation...
April 2018: Environmental Epigenetics
John I Ogren, Ashley L Tong, Samuel C Gordon, Aurélia Chenu, Yue Lu, Robert E Blankenship, Jianshu Cao, Gabriela S Schlau-Cohen
Photosynthetic purple bacteria convert solar energy to chemical energy with near unity quantum efficiency. The light-harvesting process begins with absorption of solar energy by an antenna protein called Light-Harvesting Complex 2 (LH2). Energy is subsequently transferred within LH2 and then through a network of additional light-harvesting proteins to a central location, termed the reaction center, where charge separation occurs. The energy transfer dynamics of LH2 are highly sensitive to intermolecular distances and relative organizations...
March 28, 2018: Chemical Science
Eden W McQueen, Nathan I Morehouse
Complex signaling traits such as pheromone profiles can play an important role in the early stages of reproductive isolation between populations. These signals can diverge along multiple trait axes, and signal receivers are often sensitive to subtle differences in signal properties. In the Lepidoptera, prior research has highlighted that natural selection can drive rapid chemical signal divergence, for instance via mate recognition to maintain species boundaries. Much less is known about the occurrence of such changes for predominantly sexually selected chemical signals, such as those released by many male lepidopterans...
March 1, 2018: Journal of Insect Science
Andreas Focks, Dick Belgers, Marie-Claire Boerwinkel, Laura Buijse, Ivo Roessink, Paul J Van den Brink
Exposure patterns in ecotoxicological experiments often do not match the exposure profiles for which a risk assessment needs to be performed. This limitation can be overcome by using toxicokinetic-toxicodynamic (TKTD) models for the prediction of effects under time-variable exposure. For the use of TKTD models in the environmental risk assessment of chemicals, it is required to calibrate and validate the model for specific compound-species combinations. In this study, the survival of macroinvertebrates after exposure to the neonicotinoid insecticide was modelled using TKTD models from the General Unified Threshold models of Survival (GUTS) framework...
May 1, 2018: Ecotoxicology
Jian-Ke Sun, Weiyi Zhang, Ryan Guterman, Hui-Juan Lin, Jiayin Yuan
Soft actuators with integration of ultrasensitivity and capability of simultaneous interaction with multiple stimuli through an entire event ask for a high level of structure complexity, adaptability, and/or multi-responsiveness, which is a great challenge. Here, we develop a porous polycarbene-bearing membrane actuator built up from ionic complexation between a poly(ionic liquid) and trimesic acid (TA). The actuator features two concurrent structure gradients, i.e., an electrostatic complexation (EC) degree and a density distribution of a carbene-NH3 adduct (CNA) along the membrane cross-section...
April 30, 2018: Nature Communications
Maria Martinez, Kurunthachalam Kannan
The determination of oxidative stress biomarkers (OSBs) is useful for the assessment of health status and progress of diseases in humans. Whereas previous methods for the determination of OSBs in urine were focused on a single marker, in this study, we present a method for the simultaneous determination of biomarkers of oxidative damage to lipids, proteins, and DNA. Dinitrophenylhydrazine (DNPH) derivatization followed by solid phase extraction (SPE) and high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) allowed the determination of 8-hydroxy-2'-deoxyguanosine (8-OHdG), o-o'-dityrosine (diY), malondialdehyde (MDA), and four isoprostane F2α isomers: 8-iso-prostaglandinF2α (8-PGF2α), 11β-prostaglandinF2α (11-PGF2α), 15-R-prostaglandinF2α (15-PGF2α), and 8-iso,15(R)-prostaglandinF2α (8,15-PGF2α) in urine...
April 30, 2018: Environmental Science & Technology
Sandra Doria, Timothy S Sinclair, Nathan D Klein, Doran I G Bennett, Chern Chuang, Francesca Stefania Freyria, Colby P Steiner, Paolo Foggi, Keith A Nelson, Jianshu Cao, Alán Aspuru-Guzik, Seth Lloyd, Justin Ryan Caram, Moungi G Bawendi
Photosynthetic antennae and organic electronic materials use topological, structural and molecular control of delocalized excitons to enhance and direct energy transfer. Interactions between the transition dipoles of individual chromophore units allow for coherent delocalization across multiple molecular sites. This delocalization, for specific geometries, greatly enhances the transition dipole moment of the lowest-energy excitonic state relative to the chromophore and increases its radiative rate, a phenomenon known as superradiance...
April 27, 2018: ACS Nano
Ming-Zhi Zhu, Gui-Lin Chen, Jian-Lin Wu, Na Li, Zhong-Hua Liu, Ming-Quan Guo
INTRODUCTION: Medicinal plants are gaining increasing attention worldwide due to their empirical therapeutic efficacy and being a huge natural compound pool for new drug discovery and development. The efficacy, safety and quality of medicinal plants are the main concerns, which are highly dependent on the comprehensive analysis of chemical components in the medicinal plants. With the advances in mass spectrometry (MS) techniques, comprehensive analysis and fast identification of complex phytochemical components have become feasible, and may meet the needs, for the analysis of medicinal plants...
April 23, 2018: Phytochemical Analysis: PCA
Navjot Kaur, Bhushan J Toley
There has been a recent resurgence in the use of paper as a substrate for developing point-of-care medical diagnostic tests, possibly triggered by expiring patents published in the 1990s. A hallmark of this resurgence has been the development of advanced shapes and structures made from paper to conduct multi-step fluidic operations using the wicking action of porous materials. Such devices indicate a distinct improvement over lateral flow immunoassays, which are restricted to conducting one-step operations...
April 23, 2018: Analyst
Minghui Wang, Huanshun Yin, Yunlei Zhou, Jingrui Han, Tingqun He, Lin Cui, Shiyun Ai
A photoelectrochemical biosensor is described for sensitive detection of microRNA-162a. A multiple amplification strategy is employed that involves (a) isothermal strand displacement polymerase reaction; (b) terminal deoxynucleotidyl transferase-mediated extension, (c) amplification of streptavidin-coated gold nanoparticles, and (d) biotin functionalized alkaline phosphatase. Graphite-like C3 N4 (g-C3 N4 ) nanosheets were used as photoactive material. By using these amplification strategies, the detection limit is as low as 0...
April 20, 2018: Mikrochimica Acta
Cheryl Stork, Sika Zheng
Misregulation of alternative pre-mRNA splicing contributes to various diseases. Understanding how alternative splicing is regulated paves the way to modulating or correcting molecular pathogenesis of the diseases. Alternative splicing is typically regulated by trans RNA binding proteins and their upstream modulators. Identification of these splicing regulators has been difficult and traditionally done piecemeal. High-throughput screening strategies to find multiple regulators of exon splicing have great potential to accelerate the discovery process, but typically confront low sensitivity and specificity of splicing assays...
2018: Methods in Molecular Biology
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