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https://www.readbyqxmd.com/read/27911986/persistent-organic-pollutants-in-adipose-tissue-should-be-considered-in-obesity-research
#1
Y-M Lee, K-S Kim, D R Jacobs, D-H Lee
Although low doses of persistent organic pollutants (POPs), strong lipophilic chemicals with long half-lives, have been linked to various endocrine, immune, nervous and reproductive system diseases, few obesity studies have considered adipose tissue as an important POPs exposure source. Because the toxicodynamics of POPs relate directly to the dynamics of adiposity, POPs might explain puzzling findings in obesity research. In two people exposed to the same amounts of environmental POPs, the one having more adipose tissue may be advantaged because POPs storage in adipose tissue can reduce burden on other critical organs...
December 2, 2016: Obesity Reviews: An Official Journal of the International Association for the Study of Obesity
https://www.readbyqxmd.com/read/27908461/the-vato-project-an-original-methodology-to-study-the-transfer-of-tritium-as-ht-and-hto-in-grassland-ecosystem
#2
D Maro, F Vermorel, M Rozet, C Aulagnier, D Hébert, S Le Dizès, C Voiseux, L Solier, C Cossonnet, C Godinot, B Fiévet, P Laguionie, O Connan, O Cazimajou, M Morillon, M Lamotte
Tritium ((3)H) is mainly released into the environment by nuclear power plants, military nuclear facilities and nuclear reprocessing plants. The construction of new nuclear facilities in the world as well as the evolution of nuclear fuel management might lead to an increase of (3)H discharges from the nuclear industry. The VATO project was set up by IRSN (Institut de Radioprotection et de Sûreté Nucléaire) and EDF (Electricité de France) to reduce the uncertainties in the knowledge about transfers of (3)H from an atmospheric source (currently releasing HT and HTO) to a grassland ecosystem...
November 29, 2016: Journal of Environmental Radioactivity
https://www.readbyqxmd.com/read/27905562/occurrence-temporal-trends-and-half-lives-of-perfluoroalkyl-acids-pfaas-in-occupational-workers-in-china
#3
Jianjie Fu, Yan Gao, Lin Cui, Thanh Wang, Yong Liang, Guangbo Qu, Bo Yuan, Yawei Wang, Aiqian Zhang, Guibin Jiang
Paired serum and urine samples were collected from workers in a fluorochemical plant from 2008 to 2012 (n = 302) to investigate the level, temporal trends, and half-lives of PFAAs in workers of a fluorochemical plant. High levels of perfluorohexane sulfonate (PFHxS), perfluorooctanoic acid (PFOA), and perfluorooctanesulfonate (PFOS) were detected in serum with median concentrations of 764, 427, and 1725 ng mL(-1), respectively. The half-lives of PFAAs in workers were estimated by daily clearance rates and annual decline rates of PFAAs in serum by a first-order model...
December 1, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27904871/in-vivo-measurement-and-characterization-of-a-novel-formulation-of-177-lu-dota-octreotate
#4
Dale L Bailey, Thomas M Hennessy, Kathy P Willowson, E Courtney Henry, David Lh Chan, Alireza Aslani, Paul J Roach
OBJECTIVES: Lutetium-177 can be made with high specific activity and with no other isotopes of lutetium present, referred to as "No Carrier Added" (NCA) (177)Lu. We have radiolabelled DOTA-conjugated peptide DOTA-(Tyr(3))-octreotate with NCA (177)Lu ("NCA-LuTATE") and used it in nearly 40 therapeutic administrations for subjects with neuroendocrine tumours or meningiomas. In this paper, we report on our initial studies on aspects of the biodistribution and dosimetry of NCA-LuTATE from gamma camera 2D whole body (WB) and quantitative 3D SPECT (qSPECT) (177)Lu imaging...
2016: Asia Oceania Journal of Nuclear Medicine & Biology
https://www.readbyqxmd.com/read/27898857/vitamin-e-plasma-kinetics-in-swine-show-low-bioavailability-and-short-half-life-of-%C3%AE-tocopheryl-acetate
#5
T A T G van Kempen, M H Reijersen, C de Bruijn, S De Smet, J Michiels, M G Traber, C Lauridsen
Vitamin E is important for animal production because of its effects on health and product quality, but the amount and form required remains controversial. Our objective was to quantify the absolute bioavailability of oral -α-tocopheryl acetate (α-TAc) in swine (22 ± 1 kg and 8 wk old, fitted with jugular catheters) adapted to a diet supplemented with 75 mg/kg -α-TAc; 75 mg/kg was chosen because this level represents the nonweighted average inclusion level in piglet diets across Western key swine-producing countries...
October 2016: Journal of Animal Science
https://www.readbyqxmd.com/read/27898329/simultaneous-removal-of-structurally-different-pesticides-in-a-biomixture-detoxification-and-effect-of-oxytetracycline
#6
Alejandra Huete-Soto, Mario Masís-Mora, Verónica Lizano-Fallas, Juan Salvador Chin-Pampillo, Elizabeth Carazo-Rojas, Carlos E Rodríguez-Rodríguez
The biopurification systems (BPS) used for the treatment of pesticide-containing wastewater must present a versatile degrading ability, in order to remove different active ingredients according to the crop protection programs. This work aimed to assay the simultaneous removal of several pesticides (combinations of herbicides/insecticides/fungicides, or insecticides/fungicides) in a biomixture used in a BPS over a period of 115 d, and in the presence of oxytetracycline (OTC), an antibiotic of agricultural use that could be present in wastewater from agricultural pesticide application practices...
November 26, 2016: Chemosphere
https://www.readbyqxmd.com/read/27898328/fate-of-new-three-anti-influenza-drugs-and-one-prodrug-in-the-water-environment
#7
Takashi Azuma, Mao Ishida, Kanae Hisamatsu, Ayami Yunoki, Kana Otomo, Mari Kunitou, Mai Shimizu, Kaori Hosomaru, Shiori Mikata, Yoshiki Mino
We evaluated the environmental fate of new three anti-influenza drugs, favipiravir (FAV), peramivir (PER), and laninamivir (LAN), and an active prodrug of LAN, laninamivir octanoate (LANO), in comparison with four conventional drugs, oseltamivir (OS), oseltamivir carboxylate (OC), amantadine (AMN), and zanamivir (ZAN) by photodegradation, biodegradation, and sorption to river sediments. In addition, we conducted 9-month survey of urban rivers in the Yodo River basin from 2015 to 2016 (including the influenza season) to investigate the current status of occurrence of these drugs in the river environment...
November 26, 2016: Chemosphere
https://www.readbyqxmd.com/read/27894237/new-insight-in-improving-therapeutic-efficacy-of-antipsychotic-agents-an-overview-of-improved-in-vitro-and-in-vivo-performance-efficacy-upgradation-and-future-prospects
#8
Zahid Hussain, Hnin Ei Thu, Ahmad Nazrun Shuid
Psychotic disorders are severe mental disorders that rigorously affect patient personality, critical thinking, and perceptional ability. High prevalence, global dissemination and limitations of conventional pharmacological approaches compel a significant burden to the patient, medical professionals and the healthcare system. To date, numerous orally administered therapies are available for the management of depressive disorders, schizophrenia, anxiety, bipolar disorders and autism spectrum problems. However, poor water solubility, erratic oral absorption, extensive first-pass metabolism, low oral bioavailability and short half-lives are major factors which limit the pharmaceutical significance and therapeutic feasibility of these agents...
November 25, 2016: Current Drug Targets
https://www.readbyqxmd.com/read/27893830/mechanistic-studies-and-modeling-reveal-the-origin-of-differential-inhibition-of-gag-polymorphic-viruses-by-hiv-1-maturation-inhibitors
#9
Zeyu Lin, Joseph Cantone, Hao Lu, Beata Nowicka-Sans, Tricia Protack, Tian Yuan, Hong Yang, Zheng Liu, Dieter Drexler, Alicia Regueiro-Ren, Nicholas A Meanwell, Mark Cockett, Mark Krystal, Max Lataillade, Ira B Dicker
HIV-1 maturation inhibitors (MIs) disrupt the final step in the HIV-1 protease-mediated cleavage of the Gag polyprotein between capsid p24 capsid (CA) and spacer peptide 1 (SP1), leading to the production of infectious virus. BMS-955176 is a second generation MI with improved antiviral activity toward polymorphic Gag variants compared to a first generation MI bevirimat (BVM). The underlying mechanistic reasons for the differences in polymorphic coverage were studied using antiviral assays, an LC/MS assay that quantitatively characterizes CA/SP1 cleavage kinetics of virus like particles (VLPs) and a radiolabel binding assay to determine VLP/MI affinities and dissociation kinetics...
November 2016: PLoS Pathogens
https://www.readbyqxmd.com/read/27891611/pharmacokinetics-cannot-explain-the-increased-effective-dose-requirement-for-morphine-and-midazolam-in-rats-during-their-extended-administration-alone-or-in-combination
#10
Stefan J Schaller, Saad M Alam, Jianren Mao, Yanli Zhao, Manfred Blobner, David J Greenblatt, J A Jeevendra Martyn
OBJECTIVES: Chronic administration of morphine and midazolam, alone or in combination, can induce tolerance to their effects. Data showed that co-administration of morphine and midazolam increased effective dose requirement of morphine, exceeding that observed with morphine alone. METHODS: To elucidate the pharmacokinetic component to the tolerance, we administered midazolam (2 mg/kg) and morphine (10 mg/kg) alone or their combination daily to rats for 12 days followed by a pharmacokinetic study on day 13...
November 28, 2016: Journal of Pharmacy and Pharmacology
https://www.readbyqxmd.com/read/27885618/pre-clinical-quantitative-imaging-and-mouse-specific-dosimetry-for-111-in-labelled-radiotracers
#11
Ana M Denis-Bacelar, Sarah E Cronin, Chiara Da Pieve, Rowena L Paul, Sue A Eccles, Terence J Spinks, Carol Box, Adrian Hall, Jane K Sosabowski, Gabriela Kramer-Marek, Glenn D Flux
BACKGROUND: Accurate quantification in molecular imaging is essential to improve the assessment of novel drugs and compare the radiobiological effects of therapeutic agents prior to in-human studies. The aim of this study was to investigate the challenges and feasibility of pre-clinical quantitative imaging and mouse-specific dosimetry of (111)In-labelled radiotracers. Attenuation, scatter and partial volume effects were studied using phantom experiments, and an activity calibration curve was obtained for varying sphere sizes...
December 2016: EJNMMI Research
https://www.readbyqxmd.com/read/27882482/immobilization-and-stabilization-of-beta-xylosidases-from-penicillium-janczewskii
#12
César Rafael Fanchini Terrasan, Maria Romero-Fernández, Alejandro H Orrego, Sandro Martins Oliveira, Benevides Costa Pessela, Eleonora Cano Carmona, José Manuel Guisan
β-Xylosidases are critical for complete degradation of xylan, the second main constituent of plant cell walls. A minor β-xylosidase (BXYL II) from Penicillium janczewskii was purified by ammonium sulfate precipitation (30% saturation) followed by DEAE-Sephadex chromatography in pH 6.5 and elution with KCl. The enzyme presented molecular weight (MW) of 301 kDa estimated by size exclusion chromatography. Optimal activity was observed in pH 3.0 and 70-75 °C, with higher stability in pH 3.0-4.5 and half-lives of 11, 5, and 2 min at 65, 70, and 75 °C, respectively...
November 23, 2016: Applied Biochemistry and Biotechnology
https://www.readbyqxmd.com/read/27878481/field-investigations-of-dissipations-and-residues-of-cyazofamid-in-soil-and-tomato-risk-assessment-of-human-exposure-to-cyazofamid-via-tomato-intake
#13
Zhenlan Xu, Changpeng Zhang, Jianzhong Yu, Chunrong Zhang, Min Wu, Hongmei He, Yahong Zhu, Fangyuan Lou, Yuanyuan Wu, Yanhua Wang, Liezhong Chen, Hua Zhao, Qiang Wang, Leiming Cai
Cyazofamid, as a fungicide of the novel cyanoimidazole chemical class, has been widely used to control tomato late blight. Understanding of cyazofamid residues in environment and crops is an essential prerequisite for its risk assessment. In this study, field investigations in four typical tomato-producing areas were conducted to explore the dissipation kinetics and residues of cyazofamid and its primary metabolite 4-chloro-5-p-tolylimidazole-2-carbonitrile (CCIM) in soil and tomato. A robust method using QuEChERS coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed for simultaneous analysis of cyazofamid and CCIM, with limits of quantification of 0...
November 22, 2016: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/27875788/simultaneous-determination-and-pharmacokinetic-study-of-four-phenolic-acids-in-rat-plasma-using-uflc-ms-ms-after-intravenous-administration-of-salvianolic-acid-for-injection
#14
Xiuman Xie, Jingzhuo Miao, Wanyang Sun, Jingyi Huang, Dongxiang Li, Shuming Li, Ling Tong, Guoxiang Sun
A simple, sensitive and selective ultra-fast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) method was established for simultaneous determination and pharmacokinetic study of rosmarinic acid (RA), salvianolic acid D (Sal D), lithospermic acid (LA) and salvianolic acid B (Sal B) in rat plasma after intravenous administration of salvianolic acid for injection (SAFI). Three doses of administration, containing 14, 28 and 56mg/kg, were investigated in this study. Plasma samples were pretreated using protein precipitation (PP) with pre-cooled acetonitrile...
November 5, 2016: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/27873114/dissipation-of-antibiotics-in-three-different-agricultural-soils-after-repeated-application-of-biosolids
#15
Lu Yang, Longhua Wu, Wuxing Liu, Yujuan Huang, Yongming Luo, Peter Christie
Application of biosolids to agricultural soils is one of the pathways by which antibiotics can be introduced into agricultural ecosystems. A pot experiment was conducted with repeated soil amendment with biosolids to examine the concentrations of four classes of antibiotics (tetracyclines, sulfonamides, fluoroquinolones, and macrolides) and their dissipation in three different soil types in wheat-rice rotations. Antibiotics accumulate in the soils after repeated application of biosolids. Fluoroquinolones showed stronger accumulation and persistence in the test soils than the other three classes of antibiotics...
November 21, 2016: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/27870936/photochemical-transformation-of-zearalenone-in-aqueous-solutions-under-simulated-solar-irradiation-kinetics-and-influence-of-water-constituents
#16
Elissandro S Emídio, Vânia Calisto, Mary Rosa R de Marchi, Valdemar I Esteves
The presence of estrogenic mycotoxins, such as zearalenone (ZEN), in surface waters is an emerging environmental issue. Little is known about its phototransformation behavior, which may influence its environmental fate. In this context, the phototransformation of ZEN was investigated in pure water, river water and estuarine water using simulated sunlight irradiation. Kinetic studies revealed that two concomitant processes contribute to the fate of ZEN under solar irradiation: photoisomerization and photodegradation...
November 18, 2016: Chemosphere
https://www.readbyqxmd.com/read/27867020/a-randomized-dose-escalation-study-of-intravenous-baclofen-in-healthy-volunteers-clinical-tolerance-and-pharmacokinetics
#17
Natalie S Schmitz, Linda E Krach, Lisa D Coles, Usha Mishra, Suresh K Agarwal, James C Cloyd, Robert L Kriel
BACKGROUND: Abrupt discontinuation of baclofen can result in a potentially severe withdrawal syndrome. The current treatment for baclofen withdrawal is inadequate, resulting in a critical need to develop an alternative method to prevent or treat this withdrawal syndrome. OBJECTIVE: To evaluate the safety profile and pharmacokinetics of oral (PO) and investigational intravenous (IV) baclofen formulations at clinically relevant doses. DESIGN: Randomized, open-label, dose escalation, crossover study SETTING: Contract Research Organization (CRO) METHODS: Three cohorts of 12 healthy adults received single doses of PO baclofen (10mg, 15 mg or 20 mg) and 10-minute infusions of IV baclofen (7...
November 17, 2016: PM & R: the Journal of Injury, Function, and Rehabilitation
https://www.readbyqxmd.com/read/27866104/aquatic-transformation-of-phosphite-under-natural-sunlight-and-simulated-irradiation
#18
Huimin Qiu, Jinju Geng, Hongqiang Ren, Lili Ding, Ke Xu, Yan Zhang
The phototransformation of phosphite (HPO3(2-), H2PO3(-), +3) from Lake Taihu water (THW) under natural sunlight was evaluated. No direct phosphite photoreaction was observed under sunlight. Suspended solids were shown to play important roles in the indirect photoreaction of phosphite in lake water. The phototransformation of phosphite followed pseudo-first-order reaction kinetics and the kinetics constants (k, d(-1)) decreased as: 0.0324 (original THW), 0.0236 (sterilized THW), 0.0109 (filtered THW) and 0...
November 8, 2016: Water Research
https://www.readbyqxmd.com/read/27862103/pharmacokinetics-of-imipenem-cilastatin-burn-intensive-care-unit-patients-undergoing-high-dose-continuous-venovenous-hemofiltation
#19
Bradley A Boucher, Joanna Q Hudson, David M Hill, Joseph M Swanson, G Christopher Wood, S Casey Laizure, Angela Arnold-Ross, Zhe-Yi Hu, William L Hickerson
STUDY OBJECTIVE: High dose continuous venovenous hemofiltration (CVVH) is a continuous renal replacement therapy (CRRT) used frequently inpatients with burns. However, antibiotic dosing is based on inference from studies assessing substantially different methods of CRRT. To address this knowledge gap for imipenem/cilastatin (I-C) we evaluated the systemic and extracorporeal clearances (CL) of I-C in patients with burns undergoing high dose CVVH. DESIGN: Prospective clinical pharmacokinetic study...
November 9, 2016: Pharmacotherapy
https://www.readbyqxmd.com/read/27859621/direct-oral-anticoagulant-considerations-in-solid-organ-transplantation-a-review
#20
REVIEW
David M Salerno, Demetra Tsapepas, Apostolos Papachristos, Jae-Hyung Chang, Spencer Martin, Mark A Hardy, Jaclyn McKeen
For more than sixty years, warfarin was the only oral anticoagulation agent available for use in the United States. In many recent clinical trials, several direct oral anticoagulants (DOACs) demonstrated similar efficacy with an equal or superior safety profile; with some other notable benefits. The DOACs have lower inter- and intra-patient variability, much shorter half-lives, and less known drug-drug and drug-food interactions as compared to warfarin. Despite these demonstrated benefits, the use of DOACs have not gained uniform acceptance because of lack of supportive data in special patient populations, including recipients of solid organ transplants maintained on immunosuppression...
November 16, 2016: Clinical Transplantation
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