keyword
MENU ▼
Read by QxMD icon Read
search

xenobiotic

keyword
https://www.readbyqxmd.com/read/28110046/response-of-spirodela-polyrhiza-to-cerium-subcellular-distribution-growth-and-biochemical-changes
#1
Qinsong Xu, Yuji Jiang, Weiyue Chu, Chunlei Su, Dan Hu, Qianqian Lu, Tingting Zhang
Rare earth elements are new and emerging contaminants in freshwater systems. Greater duckweed (Spirodela polyrhiza L.) is a common aquatic plant widely used in phytotoxicity tests for xenobiotic substances. In this study, the cerium (Ce) accumulation potential, the distribution of Ce in bio-molecules, and ensuing biochemical responses were investigated in greater duckweed fronds when they were exposed to Ce (0, 10, 20, 40, and 60μM). There was a concentration dependent increase in Ce accumulation, which reached a maximum of 67mgg(-1) of dry weight (DW) at 60μM Ce after 14 d...
January 19, 2017: Ecotoxicology and Environmental Safety
https://www.readbyqxmd.com/read/28109826/biological-relevance-of-effects-following-chronic-administration-of-octamethylcyclotetrasiloxane-d4-in-fischer-344-rats
#2
Wolfgang Dekant, Anthony R Scialli, Kathy Plotzke, James E Klaunig
Octamethylcyclotetrasiloxane (D4) is a cyclic siloxane primarily used as a monomer or intermediate in the production of silicone polymers resulting in potential exposure of workers, and potential low level inhalation or dermal exposure for consumers and the general public. Following a two-year inhalation toxicity study with D4 in rats, increases in uterine endometrial cystic hyperplasia and adenomas were observed at the highest concentration of D4 administered (700ppm). No other neoplasms were increased with D4 treatment...
January 18, 2017: Toxicology Letters
https://www.readbyqxmd.com/read/28109655/the-use-of-rockfish-sebastiscus-marmoratus-as-a-sentinel-species-to-assess-petroleum-hydrocarbons-pollution-a-case-study-in-quanzhou-bay-china
#3
Jun Bo, Ronghui Zheng, Weiming Kuang, Fukun Hong, Qing Xie, Yusheng Zhang
To monitor the biological effects of marine pollution, choosing a native fish species and establishing suitable biomarkers are required. In this study, the full-length cDNA of cyp1a1 was cloned from Sebastiscus marmoratus (SM-CYP1A1). Then the dose-response and time-course induction of hepatic CYP1A1 mRNA by the crude oil water-soluble fraction (WSF) were determined. Subsequently, SM-CYP1A1 mRNA was applied to investigate the biological effect of petroleum hydrocarbon pollution in Quanzhou Bay, China. The transcription levels of hepatic CYP1A1 were significantly elevated in fish caged in the polluted sites for 2weeks compared with those of the reference site, which were correlated with the concentrations of petroleum hydrocarbon and polycyclic aromatic hydrocarbon (PAH) in the surface seawaters...
January 18, 2017: Marine Pollution Bulletin
https://www.readbyqxmd.com/read/28108177/discriminating-between-adaptive-and-carcinogenic-liver-hypertrophy-in-rat-studies-using-logistic-ridge-regression-analysis-of-toxicogenomic-data-the-mode-of-action-and-predictive-models
#4
Shujie Liu, Taisuke Kawamoto, Osamu Morita, Kouichi Yoshinari, Hiroshi Honda
Chemical exposure often results in liver hypertrophy in animal tests, characterized by increased liver weight, hepatocellular hypertrophy, and/or cell proliferation. While most of these changes are considered adaptive responses, there is concern that they may be associated with carcinogenesis. In this study, we have employed a toxicogenomic approach using a logistic ridge regression model to identify genes responsible for liver hypertrophy and hypertrophic hepatocarcinogenesis and to develop a predictive model for assessing hypertrophy-inducing compounds...
January 17, 2017: Toxicology and Applied Pharmacology
https://www.readbyqxmd.com/read/28104667/carbon-catabolite-repression-and-cell-dispersal-affects-degradation-of-the-xenobiotic-compound-3-4-dichloroaniline-in-comamonas-testosteroni-wdl7-biofilms
#5
Benjamin Horemans, Philip Breugelmans, Johan Hofkens, Dirk Springael
Organic pollutant degrading biofilms in natural ecosystems and water treatment systems are often exposed to other carbon sources in addition to the pollutant. The availability of auxilliary carbon sources can lead to surplus biomass growth, changes in biofilm structure and carbon catabolite repression (CCR) which together will affect pollutant degradation rate and efficiency of the system. To understand the interplay between these processes, continuous biofilms of the 3,4-dichloroaniline (3,4-DCA) degrading Comamonas testosteroni WDL7-RFP were grown in single- and dual-substrate conditions with 3,4-DCA and/or citrate and reciprocal effects on 3,4-DCA/citrate degradation, biofilm biomass and biofilm structure were examined...
January 18, 2017: FEMS Microbiology Ecology
https://www.readbyqxmd.com/read/28100006/the-fingerprint-of-antimitochondrial-antibodies-and-the-etiology-of-primary-biliary-cholangitis
#6
Zongwen Shuai, Jinjun Wang, Madhu Badamagunta, Jinjung Choi, Guoxiang Yang, Weici Zhang, Thomas P Kenny, Kathryn Guggenheim, Mark J Kurth, Aftab A Ansari, John Voss, Ross L Coppel, Pietro Invernizzi, Patrick S C Leung, M Eric Gershwin
The identification of environmental factors that lead to loss of tolerance has been coined the Holy Grail of autoimmunity. Our work has focused on the reactivity of antimitochondrial autoantibodies (AMA) to chemical xenobiotics and has hypothesized that a modified peptide within PDC-E2, the major mitochondrial autoantigen, will have been immunologically recognized at the time of loss of tolerance. Herein we successfully applied intein technology to construct a PDC-E2 protein fragment containing amino acid residues 177-314 of PDC-E2 by joining a recombinant peptide spanning residues 177 to 252 (PDC-228) with a 62 residue synthetic peptide from 253 to 314 (PP), which encompasses PDC-E2 ILD...
January 18, 2017: Hepatology: Official Journal of the American Association for the Study of Liver Diseases
https://www.readbyqxmd.com/read/28098843/perm-hypothesis-the-fundamental-machinery-able-to-elucidate-the-role-of-xenobiotics-and-hormesis-in-cell-survival-and-homeostasis
#7
REVIEW
Salvatore Chirumbolo, Geir Bjørklund
In this article the Proteasome, Endoplasmic Reticulum and Mitochondria (PERM) hypothesis is discussed. The complex machinery made by three homeostatic mechanisms involving the proteasome (P), endoplasmic reticulum (ER) and mitochondria (M) is addressed in order to elucidate the beneficial role of many xenobiotics, either trace metals or phytochemicals, which are spread in the human environment and in dietary habits, exerting their actions on the mechanisms underlying cell survival (apoptosis, cell cycle regulation, DNA repair and turnover, autophagy) and stress response...
January 15, 2017: International Journal of Molecular Sciences
https://www.readbyqxmd.com/read/28094042/responses-of-the-rotifer-brachionus-plicatilis-to-flame-retardant-bde-47-stress
#8
Xiaoyang Jian, Xuexi Tang, Ningning Xu, Jingjing Sha, You Wang
A series of short-term toxicological tests were conducted on the rotifer Brachionus plicatilis to assess the toxicity of the flame retardant 2,2',4,4'-tetrabrominated biphenyl ether (BDE-47). BDE-47 increased mortality, morphological damage, and altered population dynamics and fecundity of rotifer. Antioxidant enzymes were differentially changed to maintain the balance between antioxidant and pro-oxidant activity. However, with increases in the concentration of BDE-47, the metabolic and antioxidant activity decreased...
January 13, 2017: Marine Pollution Bulletin
https://www.readbyqxmd.com/read/28092182/an-estrogen-receptor-%C3%AE-selective-agonist-inhibits-non-alcoholic-steatohepatitis-in-preclinical-models-by-regulating-bile-acid-and-xenobiotic-receptors
#9
Suriyan Ponnusamy, Quynh T Tran, Thirumagal Thiyagarajan, Duane D Miller, Dave Bridges, Ramesh Narayanan
Non-alcoholic steatohepatitis (NASH) affects 8-10 million people in the US and up to 75% of obese individuals. Despite this, there are no approved oral therapeutics to treat NASH and therefore the need for novel approaches exists. The estrogen receptor β (ER-β)-selective agonist, β-LGND2, inhibits body weight and white adipose tissue, and increases metabolism, resulting in higher energy expenditure and thermogenesis. Due to favorable effects of β-LGND2 on obesity, we hypothesized that β-LGND2 will prevent NASH directly by reducing lipid accumulation in the liver or indirectly by favorably changing body composition...
January 1, 2017: Experimental Biology and Medicine
https://www.readbyqxmd.com/read/28090466/microbiome-linked-crosstalk-in-the-gastrointestinal-exposome-towards-host-health-and-disease
#10
REVIEW
Yuseok Moon
The gastrointestinal exposome represents the integration of all xenobiotic components and host-derived endogenous components affecting the host health, disease progression and ultimately clinical outcomes during the lifespan. The human gut microbiome as a dynamic exposome of commensalism continuously interacts with other exogenous exposome as well as host sentineling components including the immune and neuroendocrine circuit. The composition and diversity of the microbiome are established on the basis of the luminal environment (physical, chemical and biological exposome) and host surveillance at each part of the gastrointestinal lining...
December 2016: Pediatric Gastroenterology, Hepatology & Nutrition
https://www.readbyqxmd.com/read/28089783/characterization-of-rat-or-human-hepatocytes-cultured-in-microphysiological-systems-mps-to-identify-hepatotoxicity
#11
Shih-Yu Chang, Jenna L Voellinger, Kirk P Van Ness, Brian Chapron, Rachel M Shaffer, Thomas Neumann, Collin C White, Terrance J Kavanagh, Edward J Kelly, David L Eaton
The liver is the main site for drug and xenobiotics metabolism, including inactivation or bioactivation. In order to improve the predictability of drug safety and efficacy in clinical development, and to facilitate the evaluation of the potential human health effects from exposure to environmental contaminants, there is a critical need to accurately model human organ systems such as the liver in vitro. We are developing a microphysiological system (MPS) based on a new commercial microfluidic platform (Nortis, Inc...
January 12, 2017: Toxicology in Vitro: An International Journal Published in Association with BIBRA
https://www.readbyqxmd.com/read/28089504/review-nutrient-sulfate-supply-from-mother-to-fetus-placental-adaptive-responses-during-human-and-animal-gestation
#12
REVIEW
P A Dawson, K Richard, A Perkins, Z Zhang, D G Simmons
Nutrient sulfate has numerous roles in mammalian physiology and is essential for healthy fetal growth and development. The fetus has limited capacity to generate sulfate and relies on sulfate supplied from the maternal circulation via placental sulfate transporters. The placenta also has a high sulfate requirement for numerous molecular and cellular functions, including sulfate conjugation (sulfonation) to estrogen and thyroid hormone which leads to their inactivation. Accordingly, the ratio of sulfonated (inactive) to unconjugated (active) hormones modulates endocrine function in fetal, placental and maternal tissues...
January 4, 2017: Placenta
https://www.readbyqxmd.com/read/28088650/assessing-the-identity-and-expression-level-of-the-cytochrome-p450-20a1-cyp20a1-gene-in-the-bpa-bde-47-and-waf-exposed-copepods-tigriopus-japonicus-and-paracyclopina-nana
#13
Jeonghoon Han, Duck-Hyun Kim, Jung Soo Seo, Il-Chan Kim, David R Nelson, Jayesh Puthumana, Jae-Seong Lee
CYP20A1 is a member of the cytochrome P450 (CYP) superfamily, identified as an orphan P450 without any assigned biological function; hence, its continued status as an "orphan" gene. In order to address this shortcoming in our understanding of this superfamily, we sought to characterize the CYP20A1 gene in the copepods Tigriopus japonicus (Tj-CYP20A1) and Paracyclopina nana (Pn-CYP20A1) at their mRNA transcriptional level. We assessed the response of this gene's expression in various developmental stages and in response to treatment with bisphenol A (BPA), 2, 2', 4, 4'-tetrabromodiphenyl ether (BDE-47), and water accommodated fractions (WAFs) of crude oil...
January 11, 2017: Comparative Biochemistry and Physiology. Toxicology & Pharmacology: CBP
https://www.readbyqxmd.com/read/28088094/organ-on-a-chip-for-assessing-environmental-toxicants
#14
REVIEW
Soohee Cho, Jeong-Yeol Yoon
Man-made xenobiotics, whose potential toxicological effects are not fully understood, are oversaturating the already-contaminated environment. Due to the rate of toxicant accumulation, unmanaged disposal, and unknown adverse effects to the environment and the human population, there is a crucial need to screen for environmental toxicants. Animal models and in vitro models are ineffective models in predicting in vivo responses due to inter-species difference and/or lack of physiologically-relevant 3D tissue environment...
January 11, 2017: Current Opinion in Biotechnology
https://www.readbyqxmd.com/read/28077779/embryonic-exposure-to-tcdd-impacts-osteogenesis-of-the-axial-skeleton-in-japanese-medaka-oryzias-latipes
#15
AtLee T D Watson, Antonio Planchart, Carolyn J Mattingly, Christoph Winkler, David M Reif, Seth W Kullman
Recent studies from mammalian, fish, and in vitro models have identified bone and cartilage development as sensitive targets for dioxins and other aryl hydrocarbon receptor ligands. In this study, we assess how embryonic 2,3,7,8-tetrachlorochlorodibenzo-p-dioxin (TCDD) exposure impacts axial osteogenesis in Japanese medaka (Oryzias latipes), a vertebrate model of human bone development. Embryos from inbred wild-type Orange-red Hd-dR and 3 transgenic medaka lines (twist:EGFP, osx/sp7:mCherry, col10a1:nlGFP) were exposed to 0...
November 15, 2016: Toxicological Sciences: An Official Journal of the Society of Toxicology
https://www.readbyqxmd.com/read/28074615/a-database-of-optimized-proteomic-quantitative-methods-for-284-human-drug-disposition-related-proteins-for-applications-in-pbpk-modeling
#16
Marc Vrana, Dale Whittington, Vivek Nautiyal, Bhagwat Prasad
The aim of this study was to create an open access repository of validated LC-MS/MS (MRM) methods for quantifying 284 important proteins associated with drug absorption, distribution, metabolism and excretion (ADME). Various in silico and experimental approaches were used to select surrogate peptides and optimize instrument parameters for LC-MS/MS quantification of the selected proteins. The final methods were uploaded to an online public database (ADME QPrOmics(TM); www.qpromics.uw.edu/qpromics/assay/) which provides essential information for facile method development in triple quadrupole MS instruments...
January 11, 2017: CPT: Pharmacometrics & Systems Pharmacology
https://www.readbyqxmd.com/read/28073050/genome-wide-identification-of-atp-binding-cassette-abc-transporters-and-their-roles-in-response-to-polycyclic-aromatic-hydrocarbons-pahs-in-the-copepod-paracyclopina-nana
#17
Chang-Bum Jeong, Duck-Hyun Kim, Hye-Min Kang, Young Hwan Lee, Hui-Su Kim, Il-Chan Kim, Jae-Seong Lee
The ATP-binding cassette (ABC) protein superfamily is one of the largest gene families and is highly conserved in all domains. The ABC proteins play roles in several biological processes, including multi-xenobiotic resistance (MXR), by functioning as transporters in the cellular membrane. They also mediate the cellular efflux of a wide range of substrates against concentration gradients. In this study, 37 ABC genes belonging to eight distinct subfamilies were identified in the marine copepod Paracyclopina nana and annotated based on a phylogenetic analysis...
December 30, 2016: Aquatic Toxicology
https://www.readbyqxmd.com/read/28072829/predicting-the-metabolic-sites-by-flavin-containing-monooxygenase-on-drug-molecules-using-svm-classification-on-computed-quantum-mechanics-and-circular-fingerprints-molecular-descriptors
#18
Chien-Wei Fu, Thy-Hou Lin
As an important enzyme in Phase I drug metabolism, the flavin-containing monooxygenase (FMO) also metabolizes some xenobiotics with soft nucleophiles. The site of metabolism (SOM) on a molecule is the site where the metabolic reaction is exerted by an enzyme. Accurate prediction of SOMs on drug molecules will assist the search for drug leads during the optimization process. Here, some quantum mechanics features such as the condensed Fukui function and attributes from circular fingerprints (called Molprint2D) are computed and classified using the support vector machine (SVM) for predicting some potential SOMs on a series of drugs that can be metabolized by FMO enzymes...
2017: PloS One
https://www.readbyqxmd.com/read/28071785/bioactive-polyphenols-and-cardiovascular-disease-chemical-antagonists-pharmacological-agents-or-xenobiotics-that-drive-an-adaptive-response
#19
REVIEW
Katarzyna Goszcz, Garry G Duthie, Derek Stewart, Stephen J Leslie, Ian L Megson
Polyphenols are widely regarded to have a wide range of health-promoting qualities, including in the sphere of cardiovascular disease. Historically, the benefits have been linked to their well-recognised powerful antioxidant activity. However, the concept that the beneficial effects are attributable to direct antioxidant activity in vivo does not pay sufficient heed to the fact that polyphenols degrade rapidly, are poorly absorbed and rapidly metabolised, resulting in very low bioavailability. This review explores alternative mechanisms by which polyphenols, or their metabolites, exert biological activity via mechanisms that can be activated by physiologically relevant concentrations...
January 10, 2017: British Journal of Pharmacology
https://www.readbyqxmd.com/read/28071611/microsomal-epoxide-hydrolase-gene-polymorphisms-and-susceptibility-to-prostate-cancer-a-systematic-review
#20
REVIEW
Dsl Srivastava
Microsomal epoxide hydrolase (mEH) is a crucial biotransformation enzyme that has capability to metabolize a large number of structurally divergent, highly reactive epoxides, and numerous environmentally exposed carcinogens. It catalyzes the conversion of xenobiotic epoxide compounds into more polar diol metabolites and may play important part of the enzymatic defense against adverse effects of foreign compounds. Most commonly, two functional polymorphisms affecting mEH enzyme activity have been identified: One in exon 3 and other in exon 4 of the mEH gene, which results in His113Tyr and Arg139His amino acid substitutions, respectively...
April 2016: Indian Journal of Cancer
keyword
keyword
68550
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"