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https://www.readbyqxmd.com/read/29155562/quantification-of-nanomaterial-nanomedicine-trafficking-in-vivo
#1
Liming Wang, Liang Yan, Jing Liu, Chunying Chen, Yuliang Zhao
Absorption, distribution, metabolism and excretion (ADME) of nanomaterials (NMs) or nanomedicines (NMs), are fundamental biological processes that dominate their nanomedical functions or nanotoxicities. Mostly, NMs exist in biological systems as a form of nanoparticles (NPs). However, to determine the composition, spatial distribution, and states of existence of NMs/NPs in vivo, upon entry into the body, as well as to monitor the dynamic changes of these information over time remain a challenge for the current analytical methodology due to their limited efficiently in characterizing interactions between these complex(nano)-complex(bio) systems...
November 20, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/29152616/evaluation-of-the-129-i-half-life-value-through-analyses-of-primitive-meteorites
#2
Olga Pravdivtseva, Alex Meshik, Charles M Hohenberg
The preserved record of decay of now-extinct (129)I into (129)Xe forms the basis of the I-Xe chronometer. Comparison of the high precision I-Xe and Pb-Pb ages of chondrules and pure mineral phases separated from eight meteorites suggests the 17.5 ÷ 14.6 Ma range for the (129)I half-life, assuming that the (235)U and (238)U half-lives are correct. The mean value of 16 Ma indicates that the 15.7 Ma half-life of (129)I used here for the I-Xe age calculations is most probably correct. Since the (129)I half-life value only affects the relative I-Xe ages, the few Ma relative to the Shallowater standard, the absolute I-Xe ages are almost immune to this uncertainty in the (129)I half-life...
2017: JPS Conf Proc
https://www.readbyqxmd.com/read/29149702/an-hplc-tandem-mass-spectrometry-for-quantification-of-et-26-hcl-and-its-major-metabolite-in-plasma-and-application-to-a-pharmacokinetic-study-in-rats
#3
Xu Chen, Wensheng Zhang, Sandy Rios, Miriam B Morkos, Xiaoli Ye, Gen Li, Xuehua Jiang, Zhijun Wang, Ling Wang
ET-26-HCl is a new analog of etomidate, a short-acting anesthetic drug, with less adrenal cortex inhibition. The pharmacokinetics of ET-26-HCl in rats needs to be determined for future clinical trials in human subjects. In order to facilitate the pharmacokinetic study, a liquid chromatography based tandem mass spectrometric (HPLC-MS/MS) method was developed and validated for quantification of ET-26-HCl and its major metabolite, ET-26-acid. These two compounds and gabapentin (internal standard) were extracted using a protein precipitation method with methanol and detected by Multiple Reaction Monitoring of m/z transition of 275...
November 8, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/29138497/rapid-purification-of-human-bispecific-antibodies-via-selective-modulation-of-protein-a-binding
#4
Adam Zwolak, Catherine N Leettola, Susan H Tam, Dennis R Goulet, Mehabaw G Derebe, Jose R Pardinas, Songmao Zheng, Rose Decker, Eva Emmell, Mark L Chiu
Methods to rapidly generate high quality bispecific antibodies (BsAb) having normal half-lives are critical for therapeutic programs. Here, we identify 3 mutations (T307P, L309Q, and Q311R or "TLQ") in the Fc region of human IgG1 which disrupt interaction with protein A while enhancing interaction with FcRn. The mutations are shown to incrementally alter the pH at which a mAb elutes from protein A affinity resin. A BsAb comprised of a TLQ mutant and a wild-type IgG1 can be efficiently separated from contaminating parental mAbs by differential protein A elution starting from either a) purified parental mAbs, b) in-supernatant crossed parental mAbs, or c) co-transfected mAbs...
November 14, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29137239/transcriptome-profiling-in-preadipocytes-identifies-long-noncoding-rnas-as-sam68-targets
#5
Naomi Li, Steven Hébert, Jingwen Song, Claudia L Kleinman, Stéphane Richard
The KH-type RNA binding protein Sam68 is required for adipogenesis. We have previously shown that Sam68-deficient mice have a lean phenotype and are protected against dietary-induced obesity due to defects in mTOR and S6K1 alternative splicing. Herein we profiled the transcriptome of Sam68 wild type and deficient 3T3-L1 mouse preadipocytes. We identified 652 protein-coding genes and 9 ncRNAs that were significantly altered with the loss of Sam68. As expected, downregulated genes were significantly associated with GO terms linked to cell migration, motility, and fat cell differentiation, while upregulated genes were mostly associated with GO terms linked to neurogenesis...
October 10, 2017: Oncotarget
https://www.readbyqxmd.com/read/29135439/biological-cleavage-of-the-c-p-bond-in-perfluoroalkyl-phosphinic-acids-in-male-sprague-dawley-rats-and-the-formation-of-persistent-and-reactive-metabolites
#6
Shira Joudan, Leo W Y Yeung, Scott A Mabury
BACKGROUND: Perfluoroalkyl phosphinic acids (PFPiAs) have been detected in humans, wildlife, and various environmental matrices. These compounds have been used with perfluoroalkyl phosphonic acids (PFPAs) as surfactants in consumer products and as nonfoaming additives in pesticide formulations. Unlike the structurally related perfluoroalkyl sulfonic and carboxylic acids, little is known about the biological fate of PFPiAs. OBJECTIVES: We determined the biotransformation products of PFPiAs and some pharmacokinetic parameters in a rat model...
November 3, 2017: Environmental Health Perspectives
https://www.readbyqxmd.com/read/29135198/lung-cancer-worry-and-home-screening-for-radon-and-secondhand-smoke-in-renters
#7
Ellen J Hahn, Marissa Hooper, Carol Riker, Karen M Butler, Kathy Rademacher, Amanda Wiggins, Mary Kay Rayens
Lung cancer is largely preventable by eliminating tobacco smoke and radon exposure. This exploratory study assessed the relationships of demographic factors, including having one or more smokers living in the household, and a) lung cancer worry and b) completion of home screening for radon and secondhand smoke (SHS) among renters. A convenience sample of renters (N = 47) received free test kits for radon and SHS as part of a larger study. Demographic factors, lung cancer worry, and completion of home testing were assessed at baseline...
January 2017: Journal of Environmental Health
https://www.readbyqxmd.com/read/29134820/pharmacokinetics-of-intravitreal-anti-vegf-drugs-in-vitrectomized-versus-non-vitrectomized-eyes
#8
Magdalena Edington, Julie Connolly, Ngaihang Victor Chong
Introduction The review aims to discuss effects of vitrectomy on pharmacokinetics of anti-vascular endothelial growth factor (anti-VEGF) agents, and attempt to provide treatment guidance. Areas Covered An Embase search was conducted using the terms 'anti-VEGF', 'pegaptanib', 'ranibizumab', 'bevacizumab', 'aflibercept', 'pharmacokinetics', 'half-life', 'clearance', 'metabolism', 'vitrectomy', 'vitrectomized'. Published data regarding the pharmacokinetic properties of the above drugs and the effect of vitrectomy in animal and human eyes was reviewed...
November 14, 2017: Expert Opinion on Drug Metabolism & Toxicology
https://www.readbyqxmd.com/read/29134531/enantioselective-degradation-of-myclobutanil-and-famoxadone-in-grape
#9
Chunmian Lin, Lijun Zhang, Hu Zhang, Qiang Wang, Jiahong Zhu, Jianmei Wang, Mingrong Qian
The enantioselective degradation of myclobutanil and famoxadone enantiomers in grape under open field was investigated in this study. The absolute configuration of myclobutanil and famoxadone enantiomers was determined by the combination of experimental electronic circular dichroism (ECD) and calculated ECD spectra. The enantiomers residues of myclobutanil and famoxadone in grape were measured by sensitive high-performance liquid chromatography/tandem mass spectrometry (HPLC-MS/MS). The linearity, precision, accuracy, matrix effect, and stability were assessed...
November 13, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/29133598/half-lives-of-pfos-pfhxs-and-pfoa-after-end-of-exposure-to-contaminated-drinking-water
#10
Ying Li, Tony Fletcher, Daniel Mucs, Kristin Scott, Christian H Lindh, Pia Tallving, Kristina Jakobsson
BACKGROUND: Municipal drinking water contaminated with perfluorinated alkyl acids had been distributed to one-third of households in Ronneby, Sweden. The source was firefighting foam used in a nearby airfield since the mid-1980s. Clean water was provided from 16 December 2013. OBJECTIVE: To determine the rates of decline in serum perfluorohexane sulfonate (PFHxS), perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA), and their corresponding half-lives...
November 13, 2017: Occupational and Environmental Medicine
https://www.readbyqxmd.com/read/29133549/pharmacokinetics-and-exposure-response-analysis-of-rg7667-a-combination-of-two-anti-cytomegalovirus-monoclonal-antibodies-in-a-phase-2a-randomized-trial-to-prevent-cytomegalovirus-infection-in-high-risk-kidney-transplant-recipients
#11
Rong Deng, Yehong Wang, Mauricio Maia, Tracy Burgess, Jacqueline M McBride, X Charlene Liao, Jorge A Tavel, William D Hanley
BACKGROUND: RG7667, a novel combination of two anti-cytomegalovirus (CMV) monoclonal IgG1 antibodies (MCMV5322A and MCMV3068A), was designed to block CMV entry into host cells. It was developed as a potential therapy for preventing CMV infection and disease in transplant recipients. METHODS: In a Phase 2a trial in CMV-seronegative recipients of kidney transplants from CMV-seropositive donors, RG7667 was assessed for preventing CMV infection. Patients received 4 intravenous doses of RG7667 (10 mg/kg of each antibody, n=60) or placebo (n=60) at time of transplant, and 1, 4, and 8 weeks post transplant...
November 13, 2017: Antimicrobial Agents and Chemotherapy
https://www.readbyqxmd.com/read/29132032/influence-of-body-size-metabolic-rate-and-life-history-stage-on-the-uptake-and-excretion-of-the-lampricide-3-trifluoromethyl-4-nitrophenol-tfm-by-invasive-sea-lampreys-petromyzon-marinus
#12
Laura R Tessier, Tristan A F Long, Michael P Wilkie
Invasive sea lamprey (Petromyzon marinus) are controlled in the Great Lakes using the lampricide 3-trifluoromethyl-4-nitrophenol (TFM), which is applied to streams infested with larval lamprey. However, lamprey that survive treatments (residuals) remain a challenge because they may subsequently undergo metamorphosis into parasitic juvenile animals that migrate downstream to the Great Lakes, where they feed on important sport and commercial fishes. The goal of this study was to determine if body size and life stage could potentially influence sea lamprey tolerance to TFM by influencing patterns of TFM uptake and elimination...
October 28, 2017: Aquatic Toxicology
https://www.readbyqxmd.com/read/29131625/effects-of-planting-and-processing-modes-on-the-degradation-of-dithianon-and-pyraclostrobin-in-chinese-yam-dioscorea-spp
#13
Kaiwei Shi, Xujin Wu, Jingwei Ma, Junfeng Zhang, Ling Zhou, Hong Wang, Li Li
The yam (Dioscorea spp.) is widely cultivated in China. The degradation of dithianon and pyraclostrobin in yams with different planting and processing treatments were investigated in this paper. An analytical method for two pesticides in yam and yam plant was developed, and recoveries were between 77% and 93%, with relative standard deviations from 0.8% to 7.4%, respectively. Based on this method, half-lives for plants grown on stakes versus plants grown without stakes were compared. The results indicated that the half-life for pesticides residues for plants grown on stakes versus plants grown without stakes differed as 6...
November 13, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/29124517/characterization-of-l-rhamnose-isomerase-from-clostridium-stercorarium-and-its-application-to-the-production-of-d-allose-from-d-allulose-d-psicose
#14
Min-Ju Seo, Ji-Hyeon Choi, Su-Hwan Kang, Kyung-Chul Shin, Deok-Kun Oh
OBJECTIVE: To characterize L-rhamnose isomerase (L-RI) from the thermophilic bacterium Clostridium stercorarium and apply it to produce D-allose from D-allulose. RESULTS: A recombinant L-RI from C. stercorarium exhibited the highest specific activity and catalytic efficiency (k cat/K m) for L-rhamnose among the reported L-RIs. The L-RI was applied to the high-level production of D-allose from D-allulose. The isomerization activity for D-allulose was maximal at pH 7, 75 °C, and 1 mM Mn(2+) over 10 min reaction time...
November 9, 2017: Biotechnology Letters
https://www.readbyqxmd.com/read/29123332/target-or-clear-zirconium-89-labeled-silica-nanoparticles-for-enhanced-cancer-directed-uptake-in-melanoma-a-comparison-of-radiolabeling-strategies
#15
Feng Chen, Kai Ma, Li Zhang, Brian Madajewski, Pat Zanzonico, Sonia Sequeira, Mithat Gonen, Ulrich Wiesner, Michelle S Bradbury
Designing a nanomaterials platform with high target-to-background ratios has long been one of the major challenges in the field of nanomedicine. Here, we introduce a "target-or-clear" multifunctional nanoparticle platform that demonstrates high tumor-targeting efficiency and retention while minimizing off-target effects. Encouraged by the favorable preclinical and clinical pharmacokinetic profiles derived after fine-tuning surface chemical properties of radioiodinated ((124)I, t1/2 = 100.2 h) ultrasmall cRGDY-conjugated fluorescent silica nanoparticles (C dots), we sought to investigate how the biological properties of these radioconjugates could be influenced by the conjugation of radiometals such as zirconium-89 ((89)Zr, t1/2 = 78...
October 10, 2017: Chemistry of Materials: a Publication of the American Chemical Society
https://www.readbyqxmd.com/read/29120807/residual-behavior-and-risk-assessment-of-tridemorph-in-banana-conditions
#16
Siwei Wang, Haibin Sun, Yanping Liu
An efficient method has been developed for determining tridemorph in banana using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The dissipation and terminal residue of tridemorph in banana fields were carried out at good agricultural practice (GAP) conditions. The average recoveries ranged from 84.4% to 90.0% with relative standard deviations (RSDs) of 3.0%-7.0% at three different spiking levels. The results indicated that the tridemorph dissipated quickly in banana with half-lives of 7...
April 1, 2018: Food Chemistry
https://www.readbyqxmd.com/read/29119496/photolytic-degradation-of-ciprofloxacin-in-solid-and-aqueous-environments-kinetics-phototransformation-pathways-and-byproducts
#17
Yen-Ching Lin, Kuan-Wen Hsiao, Angela Yu-Chen Lin
Many lipophilic pharmaceuticals may be sorbed in solid phases, leading to different photochemical behaviors. This study investigated the photochemistry of ciprofloxacin in a solid-phase system and compared it to that in a water-phase system. Kaolinite was used as the model solid matrix. The photolysis of ciprofloxacin in kaolinite fits pseudo-first-order kinetics for thicknesses less than 199 μm, and the rate constants k p decreased from 0.0154 to 0.0016 min(-1) as the thickness of the layer increased. Unlike the aqueous phase, two-step degradation processes were observed for all kaolinite layer thicknesses (14-199 μm), and the pseudo-first-order constant at the surface of the kaolinite layer was smaller than that in the water phase...
November 9, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/29116801/effects-of-surface-charge-of-hyperbranched-polymers-on-cytotoxicity-dynamic-cellular-uptake-and-localization-hemotoxicity-and-pharmacokinetics-in-mice
#18
Liyu Chen, Joshua D Simpson, Adrian V Fuchs, Barbara E Rolfe, Kristofer J Thurecht
Nanoscaled polymeric materials are increasingly being investigated as pharmaceutical products, drug/gene delivery vectors, or health-monitoring devices. Surface charge is one of the dominant parameters that regulates nanomaterial behavior in vivo. In this paper, we demonstrated how control over chemical synthesis allowed manipulation of nanoparticle surface charge, which in turn greatly influenced the in vivo behavior. Three methacrylate/methacrylamide-based monomers were used to synthesize well-defined hyperbranched polymers (HBP) by reversible addition-fragmentation chain transfer (RAFT) polymerization...
November 8, 2017: Molecular Pharmaceutics
https://www.readbyqxmd.com/read/29116759/selective-binding-to-mrna-duplex-regions-by-chemically-modified-pnas-stimulates-ribosomal-frameshifting
#19
Ru Ying Puah, Huan Jia, Manikantha Maraswami, Desiree-Faye Kaixin Toh, Rya Ero, Lixia Yang, Kiran M Patil, Alan Ann Lerk Ong, Manchugondanahalli S Krishna, Ruimin Sun, Cailing Tong, Mei Huang, Xin Chen, Teck-Peng Loh, Yonggui Gao, Ding Xiang Liu, Gang Chen
Minus-one programmed ribosomal frameshifting (-1 PRF) allows the precise maintenance of the ratio between viral proteins, and is involved in the regulation of the half-lives of cellular mRNAs. Minus-one ribosomal frameshifting (-1 RF) is activated by several stimulatory elements such as a heptameric slippery sequence (X XXY YYZ) and an mRNA secondary structure (hairpin or pseudoknot) that is positioned 2-8 nucleotides downstream from the slippery site. Upon -1 RF, the ribosomal reading frame is shifted from the normal zero frame to the -1 frame with the heptameric slippery sequence decoded as XXX YYY Z instead of X XXY YYZ...
November 8, 2017: Biochemistry
https://www.readbyqxmd.com/read/29112723/in-vitro-and-in-vivo-studies-of-the-als-ftld-protein-chchd10-reveal-novel-mitochondrial-topology-and-protein-interactions
#20
S R Burstein, F Valsecchi, H Kawamata, M Bourens, R Zeng, A Zuberi, T A Milner, S M Cloonan, C Lutz, A Barrientos, G Manfredi
Mutations in coiled-coil-helix-coiled-coil-helix-domain containing 10 (CHCHD10), a mitochondrial twin CX9C protein whose function is still unknown, cause myopathy, motor neuron disease, frontotemporal dementia, and Parkinson's disease. Here, we investigate CHCHD10 topology and its protein interactome, as well as the effects of CHCHD10 depletion or expression of disease-associated mutations in wild-type cells. We find that CHCHD10 associates with membranes in the mitochondrial intermembrane space, where it interacts with a closely related protein, CHCHD2...
November 3, 2017: Human Molecular Genetics
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