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https://www.readbyqxmd.com/read/28331292/an-open-label-two-period-comparative-study-on-pharmacokinetics-and-safety-of-a-combined-ethinylestradiol-gestodene-transdermal-contraceptive-patch
#1
Chao Zhang, Haiyan Li, Xin Xiong, Suodi Zhai, Yudong Wei, Shuang Zhang, Yuanyuan Zhang, Lin Xu, Li Liu
We investigated the pharmacokinetics and safety profiles of a newly developed combined ethinylestradiol (EE)/gestodene (GSD) transdermal contraceptive patch after a single-dose administration and compared with the market available tablet formulation in healthy adult subjects. An open-label, two-period comparative study was conducted in 12 healthy women volunteers. A single dose of the study combined EE/GE transdermal contraceptive patch and oral tablet (Milunet(®)) were administered. Blood samples at different time points after dose were collected, and concentrations were analyzed...
2017: Drug Design, Development and Therapy
https://www.readbyqxmd.com/read/28323424/toward-a-comprehensive-global-emission-inventory-of-c4-c10-perfluoroalkane-sulfonic-acids-pfsas-and-related-precursors-focus-on-the-life-cycle-of-c8-based-products-and-ongoing-industrial-transition
#2
Zhanyun Wang, Justin M Boucher, Martin Scheringer, Ian T Cousins, Konrad Hungerbuehler
Here a new global emission inventory of C4-C10 perfluoroalkanesulfonic acids (PFSAs) from the life cycle of perfluorooctanesulfonyl fluoride (POSF)-based products in 1958-2030 is presented. In particular, we substantially improve and expand the previous frameworks by incorporating missing pieces (e.g., emissions to soil through land treatment, overlooked precursors) and updating parameters (e.g., emission factors, degradation half-lives). In 1958-2015, total direct and indirect emissions of perfluorooctanesulfonic acid (PFOS) are estimated as 1228-4930 tonnes, and emissions of PFOS precursors are estimated as 1230-8738 and approximately 670 tonnes for x-perfluorooctanesulfonamides/sulfonamido ethanols (xFOSA/Es) and POSF, respectively...
March 21, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28319370/uptake-and-disposition-of-select-pharmaceuticals-by-bluegill-exposed-at-constant-concentrations-in-a-flow-through-aquatic-exposure-system
#3
Jian-Liang Zhao, Edward T Furlong, Heiko L Schoenfuss, Dana Ward Kolpin, Kyle L Bird, David J Feifarek, Eric A Schwab, Guang-Guo Ying
The increasing use of pharmaceuticals has led to their subsequent input into and release from wastewater treatment plants, with corresponding discharge into surface waters that may subsequently exert adverse effects upon aquatic organisms. Although the distribution of pharmaceuticals in surface water has been extensively studied, the details of uptake, internal distribution, and kinetic processing of pharmaceuticals in exposed fish have received less attention. For this research, we investigated the uptake, disposition, and toxicokinetics of five pharmaceuticals (diclofenac, methocarbamol, rosuvastatin, sulfamethoxazole, and temazepam) in bluegill sunfish (Lepomis macrochirus) exposed to environmentally relevant concentrations (1,000-4,000 ng L-1) in a flow-through exposure system...
March 20, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28317759/the-effects-of-gallic-ferulic-caffeic-acids-on-colour-intensification-and-anthocyanin-stability
#4
Bing-Jun Qian, Jian-Hua Liu, Shu-Juan Zhao, Jian-Xiong Cai, Pu Jing
The mechanism by which copigments stabilize colour, by protecting anthocyanin chromophores from nucleophilic attack, seems well accepted. This study was to determine effects of gallic/ferulic/caffeic acids on colour intensification and anthocyanin stability. Molecular dynamics simulations were applied to explore molecular interactions. Phenolic acids intensified the colour by 19%∼27%. Colour fading during heating followed first-order reactions with half-lives of 3.66, 9.64, 3.50, and 3.39h, whereas anthocyanin degradation, determined by the pH differential method (or HPLC-PDA), followed second-order reactions with half-lives of 3...
August 1, 2017: Food Chemistry
https://www.readbyqxmd.com/read/28316005/purification-kinetic-and-thermodynamic-characteristics-of-an-exo-polygalacturonase-from-penicillium-notatum-with-industrial-perspective
#5
Faiza Amin, Haq Nawaz Bhatti, Muhammad Bilal, Muhammad Asgher
An extracellular exo-polygalacturonase (exo-PG) produced by Penicillium notatum was purified (3.07-folds) by ammonium sulfate fractionation, ion exchange, and gel filtration chromatography. Two distinct isoforms of the enzyme, namely exo-PGI and exo-PGII, were identified during column purification with molecular weights of 85 and 20 kDa, respectively, on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The enzyme displayed its optimum activity at pH 6.0 and 50 °C and was found to be stable in the slightly acidic pH (ranging from 4...
March 18, 2017: Applied Biochemistry and Biotechnology
https://www.readbyqxmd.com/read/28303760/intrinsic-gas-production-kinetics-of-selected-intermediates-in-anaerobic-filters-for-demand-orientated-energy-supply
#6
Johannes Hagen Krümpel, Lukas Illi, Andreas Lemmer
In consequence of a growing share of solar and wind power, recent research on biogas production highlighted a need for demand-orientated, flexible gas production to provide grid services and enable a decentralized stabilization of the electricity infrastructure. Two-staged anaerobic digestion is particularly suitable for shifting the methane production into times of higher demand due to the spatio-temporal separation of hydrolysis and methanogenesis. To provide a basis for predicting gas production in an Anaerobic Filter, kinetic parameters of gas production have been determined experimentally in this study...
March 17, 2017: Environmental Technology
https://www.readbyqxmd.com/read/28300363/activation-of-hip-prostheses-in-high-energy-radiotherapy-and-resultant-dose-to-nearby-tissue
#7
Stephanie Keehan, Ryan L Smith, Jeremy Millar, Max Esser, Michael L Taylor, Peta Lonski, Tomas Kron, Rick D Franich
High energy radiotherapy can produce contaminant neutrons through the photonuclear effect. Patients receiving external beam radiation therapy to the pelvis may have high-density hip prostheses. Metallic materials such as those in hip prostheses, often have high cross-sections for neutron interaction. In this study, Thackray (UK) prosthetic hips have been irradiated by 18 MV radiotherapy beams to evaluate the additional dose to patients from the activation products. Hips were irradiated in- and out-of field at various distances from the beam isocenter to assess activation caused in-field by photo-activation, and neutron activation which occurs both in and out-of-field...
March 2017: Journal of Applied Clinical Medical Physics
https://www.readbyqxmd.com/read/28298240/interstrain-differences-in-the-expression-and-activity-of-cyp2a5-in-the-mouse-liver
#8
Katia S Poça, Thiago E M Parente, Lucas F Chagas, Bruna S Leal, Hellen S Leal, Francisco J R Paumgartten, Ana C A X De-Oliveira
BACKGROUND: Cytochrome P450 2A5 (Cyp2a5), a mouse enzyme orthologous of human CYP2A6, catalyzes a number of toxicologically important reactions, including the metabolism of nicotine, aflatoxin B1, and several other xeno- and endobiotics. Cyp2a5 expression is complex and not yet fully understood. We investigated inter-strain differences in the activity and mRNA expression of hepatic Cyp2a5. Cyp1a1/2 and Cyp2b9/10 activities were evaluated for comparative purposes. Data on the interstrain differences in the expression and activity of Cyp2a5 are important to select a suitable mouse model for studying CYP2A6-mediated metabolism...
March 15, 2017: BMC Research Notes
https://www.readbyqxmd.com/read/28287716/biocide-runoff-from-building-facades-degradation-kinetics-in-soil
#9
Ulla E Bollmann, David Fernández-Calviño, Kristian K Brandt, Morten S Storgaard, Hans Sanderson, Kai Bester
Biocides are common additives in building materials. In-can and film preservatives in polymer-resin render and paint, as well as wood preservatives are used to protect facade materials from microbial spoilage. Biocides leach from the facade material with driving rain, leading to highly polluted runoff water (up to several mg L(-1) biocides) being infiltrated into the soil surrounding houses. In the present study the degradation rates in soil of 11 biocides used for the protection of building materials were determined in laboratory microcosms...
March 23, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28285944/combination-antitumor-therapy-with-targeted-dual-nanomedicines
#10
REVIEW
Wenbing Dai, Xiaoyou Wang, Ge Song, Tongzhou Liu, Bing He, Hua Zhang, Xueqing Wang, Qiang Zhang
Combination therapy is one of the important treatment strategies for cancer at present. However, the outcome of current combination therapy based on the co-administration of conventional dosage forms is suboptimal, due to the short half-lives of chemodrugs, their deficient tumor selectivity and so forth. Nanotechnology-based targeted delivery systems show great promise in addressing the associated problems and providing superior therapeutic benefits. In this review, we focus on the combination of therapeutic strategies between different nanomedicines or drug-loaded nanocarriers, rather than the co-delivery of different drugs via a single nanocarrier...
March 7, 2017: Advanced Drug Delivery Reviews
https://www.readbyqxmd.com/read/28283988/nicotine-population-pharmacokinetics-in-healthy-adult-smokers-a-retrospective-analysis
#11
Mathilde Marchand, Patrick Brossard, Henri Merdjan, Nicola Lama, Rolf Weitkunat, Frank Lüdicke
BACKGROUND AND OBJECTIVE: Characterizing nicotine pharmacokinetics is challenging in the presence of background exposure. We performed a combined retrospective population pharmacokinetic analysis of 8 trials, including exposure to Tobacco Heating System and cigarettes (both inhaled), nicotine nasal spray and oral nicotine gum. METHOD: Data from 4 single product use trials were used to develop a population pharmacokinetic model with Phoenix(®) NLME™ and to derive exposure parameters...
March 10, 2017: European Journal of Drug Metabolism and Pharmacokinetics
https://www.readbyqxmd.com/read/28281889/isolation-and-characterization-of-polycyclic-aromatic-hydrocarbon-degrading-bacteria-with-tolerance-to-hypoxic-environments
#12
Chun-Hua Li, Chun Ye, Xiao-Peng Hou, Ming-Hua Chen, Xiang-Yong Zheng, Xu-Yi Cai
Hypoxic conditions are considerably different from aerobic and anaerobic conditions, and they are widely distributed in natural environments. Many pollutants, including polycyclic aromatic hydrocarbons (PAHs), tend to accumulate in hypoxic environments. However, PAH biodegradation under hypoxic conditions is poorly understood compared with that under obligate aerobic and obligate anaerobic conditions. In the present study, PAH-degrading bacteria were enriched, and their biodegradation rates were tested using a hypoxic station with an 8% oxygen concentration...
March 10, 2017: Journal of Environmental Science and Health. Part A, Toxic/hazardous Substances & Environmental Engineering
https://www.readbyqxmd.com/read/28281054/high-contribution-of-the-particulate-uptake-pathway-to-metal-bioaccumulation-in-the-tropical-marine-clam-gafrarium-pectinatum
#13
Laetitia Hédouin, Marc Metian, Jean-Louis Teyssié, Renaud Fichez, Michel Warnau
The clam Gafrarium pectinatum was investigated to assess its usefulness as a bioindicator species of metal mining contamination in the New Caledonia lagoon. The uptake and depuration kinetics of Ag, Cd, Co, Cr, and Zn were determined following exposures via seawater, sediment, and food using highly sensitive radiotracer techniques ((110m)Ag, (109)Cd, (51)Cr, (57)Co, and (65)Zn). When the clams were exposed to dissolved metals, Co, Zn, and Ag were readily incorporated in their tissues (concentration factors (CF) ranging from 181 to 4982 after 28 days of exposure) and all metals were strongly retained (biological half-lives always >2 months)...
March 9, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28280397/pharmacokinetics-and-outcome-of-tazobactam-piperacillin-in-japanese-patients-undergoing-low-flow-continuous-renal-replacement-therapy-dosage-considerations
#14
Hanako Kohama, Takeshi Ide, Kazuro Ikawa, Norifumi Morikawa, Shinichi Nishi
BACKGROUND: Tazobactam/piperacillin (TAZ/PIPC), which is often combined with continuous renal replacement therapy (CRRT), induces renal excretion and is thought to have a high component removal rate for blood purification. CRRT procedures vary depending on the country, region, and institution. It is not clear whether the dose of TAZ/PIPC for use in Japan can be determined based on studies conducted in other countries. Therefore, in this study, we examined the suitability of recommended dose in Japan...
2017: Clinical Pharmacology: Advances and Applications
https://www.readbyqxmd.com/read/28279968/newly-formed-reticulated-platelets-undermine-pharmacokinetically-short-lived-antiplatelet-therapies
#15
Paul C Armstrong, Thomas Hoefer, Rebecca B Knowles, Arthur Tucker, Melissa A Hayman, Plinio M Ferreira, Melissa V Chan, Timothy D Warner
OBJECTIVE: Aspirin together with thienopyridine P2Y12 inhibitors, commonly clopidogrel, is a cornerstone of antiplatelet therapy. However, many patients receiving this therapy display high on-treatment platelet reactivity, which is a major therapeutic hurdle to the prevention of recurrent thrombotic events. The emergence of uninhibited platelets after thrombopoiesis has been proposed as a contributing factor to high on-treatment platelet reactivity. Here, we investigate the influences of platelet turnover on platelet aggregation in the face of different dual-antiplatelet therapy strategies...
March 9, 2017: Arteriosclerosis, Thrombosis, and Vascular Biology
https://www.readbyqxmd.com/read/28277671/enzyme-cleavable-polymeric-micelles-for-the-intracellular-de-livery-of-pro-apoptotic-peptides
#16
Hanna B Kern, Selvi Srinivasan, Anthony J Convertine, David Hockenbery, Oliver W Press, Patrick S Stayton
Peptides derived from the third Bcl-2 homology domain (BH3) renormalize apoptotic signaling by antagonizing pro-survival Bcl-2 family members. They serve as a model for potential peptide drugs that possess therapeutic activities but are limited by delivery barriers including short circulation half-lives and poor penetration into cells. A diblock polymeric micelle carrier for the BIM BH3 peptide was recently described that demonstrated anti-tumor activity in a B-cell lymphoma xenograft model [Berguig et al., Mol Ther, 2015]...
March 9, 2017: Molecular Pharmaceutics
https://www.readbyqxmd.com/read/28277182/pharmacokinetic-analysis-of-thymol-carvacrol-and-diallyl-disulfide-after-intramammary-and-topical-applications-in-healthy-organic-dairy-cattle
#17
Sharon E Mason, Keena A E Mullen, Kevin L Anderson, Steven P Washburn, James L Yeatts, Ronald E Baynes
Mastitis is among the most costly concerns for dairy producers whether cattle are managed conventionally or organically. Unfortunately, there are no USFDA-approved mastitis treatments that allow dairy cows in the United States to maintain organic dairy status. We investigated the plasma pharmacokinetics of three organic mastitis products currently used by organic producers and organic dairy veterinarians. Those products include intramammary, topical and intravaginal preparations, each dosed at two levels. Additionally, tissue data were collected for kidney, liver and fat in order to estimate a withholding time for each of the products...
February 14, 2017: Food Additives & Contaminants. Part A, Chemistry, Analysis, Control, Exposure & Risk Assessment
https://www.readbyqxmd.com/read/28272365/simultaneous-determination-of-three-furanocoumarins-by-uplc-ms-ms-application-to-pharmacokinetic-study-of-angelica-dahurica-radix-after-oral-administration-to-normal-and-experimental-colitis-induced-rats
#18
Youn-Hwan Hwang, Hye Jin Yang, Jin Yeul Ma
In traditional oriental medicine, Angelica dahurica Radix (ADR) is used in the treatment of gastrointestinal, respiratory, neuromuscular, and dermal disorders. We evaluated the pharmacokinetic profiles of oxypeucedanin, imperatorin, and isoimperatorin, major active ingredients of ADR, in normal and 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis rats. A rapid, sensitive, and validated UPLC/MS/MS method was established for evaluating the pharmacokinetics of three furanocoumarins. After oral administration of ADR (0...
March 7, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28270565/midostaurin-a-novel-protein-kinase-inhibitor-for-the-treatment-of-acute-myelogenous-leukemia-insights-from-human-absorption-metabolism-and-excretion-studies-of-a-bddcs-ii-drug
#19
Handan He, Phi Tran, Helen Gu, Vivienne Tedesco, Jin Zhang, Wen Lin, Ewa Gatlik, Kai Klein, Tycho Heimbach
The absorption, metabolism and excretion of midostaurin, a potent class III tyrosine protein kinase inhibitor for acute myelogenous leukemia, were evaluated in healthy subjects. A microemulsion formulation was chosen to optimize absorption. After a 50 mg [14C]midostaurin dose, oral absorption was high (> 90%) and relatively rapid. In plasma, the major circulating components were midostaurin (22%), CGP52421 (32.7%), and CGP62221 (27.7%). Long plasma half-lives were observed for midostaurin (20.3 h), CGP52421 (495 h), and CGP62221 (33...
March 7, 2017: Drug Metabolism and Disposition: the Biological Fate of Chemicals
https://www.readbyqxmd.com/read/28268127/spectrophotometric-method-for-the-quantitative-assay-of-n-hydroxysulfosuccinimide-esters-including-extinction-coefficients-and-reaction-kinetics
#20
Rivo Presentini
A quantitative spectrophotometric method has been developed for the analysis of N-hydroxysulfosuccinimide (sulfo-NHS), a chromophore with a maximum absorbance at 268 nm. The extinction coefficients were determined between pH 6.0 and 8.0 and found to vary in a nonlinear manner. This spectrophotometric profile is not present in its esters which however release an equimolar amount of sulfo-NHS when they react with nucleophilic groups or hydrolyze in aqueous solution. This fact facilitates the determination in solution of the concentration and purity of bis(sulfosuccinimidyl) suberate (BS3) used as a model, as well as the examination of hydrolysis and aminolysis half-lives in different reaction conditions, these parameters being valuable in optimization of the use of the active esters...
March 6, 2017: Analytical Biochemistry
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