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https://www.readbyqxmd.com/read/28936681/production-of-r-mandelic-acid-using-nitrilase-from-recombinant-e-coli-cells-immobilized-with-tris-hydroxymethyl-phosphine
#1
Xin-Hong Zhang, Zhi-Qiang Liu, Ya-Ping Xue, Yuan-Shan Wang, Bo Yang, Yu-Guo Zheng
Recombinant Escherichia coli cells harboring nitrilase from Alcaligenes faecalis were immobilized using tris(hydroxymethyl)phosphine (THP) as the coupling agent. The optimal pH and temperature of the THP-immobilized cells were determined at pH 8.0 and 55 °C. The half-lives of THP-immobilized cells measured at 35, 40, and 50 °C were 1800, 965, and 163 h, respectively. The concentration of R-mandelic acid (R-MA) reached 358 mM after merely 1-h conversion by the immobilized cells with 500 mM R,S-mandelonitrile (R,S-MN), affording the highest productivity of 1307 g L(-1) day(-1) and the space-time productivity of 143...
September 22, 2017: Applied Biochemistry and Biotechnology
https://www.readbyqxmd.com/read/28935471/prevalence-and-decay-of-maternal-pneumococcal-and-meningococcal-antibodies-a-meta-analysis-of-type-specific-decay-rates
#2
Merryn Voysey, Andrew J Pollard, Manish Sadarangani, Thomas R Fanshawe
BACKGROUND: At the time of an infant's initial vaccination at age ∼2 to 3months, some infants already have maternal antibodies against vaccine antigens and these can suppress the immune response to vaccination. Modelling the effects of maternal antibody and the timing of infant doses on the antibody response to vaccination, requires estimates of the rate of maternal antibody decay. Decay rates are not well characterised in the medical literature. We investigated variation in the prevalence of maternal anti-capsular pneumococcal and meningococcal antibodies in infants in 14 countries, and estimated type-specific half-lives...
September 18, 2017: Vaccine
https://www.readbyqxmd.com/read/28929222/urinary-excretion-kinetics-of-the-metabolite-n-methylmalonamic-acid-nmma-after-oral-dosage-of-chloromethylisothiazolinone-and-methylisothiazolinone-in-human-volunteers
#3
T Schettgen, T Kraus
Methylisothiazolinone (MI) as well as the mixture of chloromethylisothiazolinone/methyl-iso-thiazolinone (MCI/MI, 3:1) are widespread biocides used in personal care products with potential consumer exposure. Their use is currently under discussion because of rising rates of skin sensitization against these substances in the general population. We have examined the human metabolism of methylisothiazolinone and chloromethylisothiazolinone after oral dosage of stable isotope-labelled analogues. Four human volunteers received 2 mg of labelled MI and MCI separately and at least 2 weeks apart...
September 19, 2017: Archives of Toxicology
https://www.readbyqxmd.com/read/28921438/purification-methods-for-recombinant-factor-viii-expressed-in-human-liver-sk-hep-cells
#4
Vladimir Granovski, Mario Soares Abreu-Neto, Dimas Tadeu Covas
Coagulation factor VIII is one of the largest proteins attempted to be expressed in recombinant form. A very complex and labile protein which has a very short half-live and need a fast and efficient purification chain. Here, we describe a simple purification sequence using multimodal Capto MMC, affinity FVIII select and ion exchange SP-Fastflow chromatography steps without subjecting the target molecule to mechanical and temperature stress, separating impurities from rFVIII using net charge, hydrophobicity, and affinity of the molecules...
2018: Methods in Molecular Biology
https://www.readbyqxmd.com/read/28918541/enzymatic-hydrolysis-of-black-liquor-xylan-by-a-novel-xylose-tolerant-thermostable-%C3%AE-xylosidase-from-a-tropical-strain-of-aureobasidium-pullulans-cbs-135684
#5
Wichanee Bankeeree, Rinji Akada, Pongtharin Lotrakul, Hunsa Punnapayak, Sehanat Prasongsuk
From three cell-associated β-xylosidases produced by Aureobasidium pullulans CBS 135684, the principal enzyme was enriched to apparent homogeneity and found to be active at high temperatures (60-70 °C) over a pH range of 5-9 with a specific activity of 163.3 units (U) mg(-1). The enzyme was thermostable, retaining over 80% of its initial activity after a 12-h incubation at 60 °C, with half-lives of 38, 22, and 10 h at 60, 65, and 70 °C, respectively. Moreover, it was tolerant to xylose inhibition with a K i value of 18 mM...
September 16, 2017: Applied Biochemistry and Biotechnology
https://www.readbyqxmd.com/read/28917198/dissipation-behavior-and-residue-distribution-of-fluazaindolizine-and-its-seven-metabolites-in-tomato-ecosystem-based-on-sax-spe-procedure-using-hplc-qqq-ms-ms-technique
#6
Xiaoxin Chen, Xi Li, Kyongjin Pang, Xueqi Fan, Yecheng Ma, Jiye Hu
Fluazaindolizine suspension concentrate (500gL(-1) SC), as a pre-commercialized product, was firstly investigated under open-field conditions. A sensitive method for simultaneous determination of fluazaindolizine and seven metabolites (IN-QEK31, IN-F4106, IN-A5760, IN-UJV12, IN-UNS90, IN-QZY47 and IN-TMQ01) was established and validated using HPLC-QqQ-MS/MS technique. The LOQs of these pollutants in tomato were 0.01mgkg(-1), and their recoveries were 81.1%-117% with the relative standard deviations (RSDs <11...
August 25, 2017: Journal of Hazardous Materials
https://www.readbyqxmd.com/read/28916482/disposition-of-treosulfan-and-its-active-monoepoxide-in-a-bone-marrow-liver-lungs-brain-and-muscle-studies-in-a-rat-model-with-clinical-relevance
#7
Michał Romański, Anna Kasprzyk, Mateusz Walczak, Agnieszka Ziółkowska, Franciszek Główka
For the recent years, the application of treosulfan (TREO)-based conditioning prior to hematopoietic stem cell transplantation (HSCT) has been increasing as an alternative to busulfan-based therapy, especially for patients presenting high risk of developing hepato-, pulmo-, and neurotoxicity. So far, the penetration of TREO and its epoxy-derivatives into central nervous system and aqueous humor of the eye has been investigated. However, lacking knowledge on the compounds distribution into the other key tissues precludes comprehensive understanding and assessment of TREO clinical efficacy and toxicity...
September 12, 2017: European Journal of Pharmaceutical Sciences
https://www.readbyqxmd.com/read/28913596/-perioperative-management-of-immunosuppressive-treatment-in-patients-undergoing-joint-surgery
#8
K Krüger
The perioperative management of patients on immunosuppressive drugs is uncertain due to a lack of controlled studies. Continuation of medication without a pause may increase the risk of postoperative infections and wound healing disorders and when the pause is too long this can induce a flare of the underlying rheumatic disease. Additional factors, such as rheumatic disease activity, comorbidities, previous infections and the type of surgical procedure also modulate the risk. The highest risk of infection is associated with corticosteroids depending on the dose, so that a dosage as low as possible but stable in the perioperative period is recommended...
September 14, 2017: Zeitschrift Für Rheumatologie
https://www.readbyqxmd.com/read/28913159/enzymatic-characterization-of-a-recombinant-carbonyl-reductase-from-acetobacter-sp-cctcc-m209061
#9
Ping Wei, Yu-Han Cui, Min-Hua Zong, Pei Xu, Jian Zhou, Wen-Yong Lou
BACKGROUND: Acetobacter sp. CCTCC M209061 could catalyze carbonyl compounds to chiral alcohols following anti-Prelog rule with excellent enantioselectivity. Therefore, the enzymatic characterization of carbonyl reductase (CR) from Acetobacter sp. CCTCC M209061 needs to be investigated. RESULTS: A CR from Acetobacter sp. CCTCC M209061 (AcCR) was cloned and expressed in E. coli. AcCR was purified and characterized, finding that AcCR as a dual coenzyme-dependent short-chain dehydrogenase/reductase (SDR) was more preferred to NADH for biocatalytic reactions...
2017: Bioresources and Bioprocessing
https://www.readbyqxmd.com/read/28906561/bioequivalence-of-intravenous-and-oral-rolapitant-results-from-a-randomized-open-label-pivotal-study
#10
Xiaodong Wang, Zhi-Yi Zhang, Daniel Powers, Jing Wang, Sharon Lu, Sujata Arora, Lorraine Hughes, Jennifer Christensen, Vikram Kansra
Rolapitant, a selective and long-acting neurokinin-1 receptor antagonist, is approved in an oral formulation for the prevention of delayed chemotherapy-induced nausea and vomiting in adults. The objective of this pivotal study was to assess the bioequivalence of a single intravenous infusion of rolapitant versus a single oral dose of rolapitant. In this randomized, open-label phase 1 study, healthy volunteers were administered rolapitant as a 180-mg oral dose or a 30-minute 166.5-mg intravenous infusion. Blood samples for pharmacokinetic analysis were collected predose and at points up to 912 hours postdose...
September 14, 2017: Journal of Clinical Pharmacology
https://www.readbyqxmd.com/read/28903827/pharmacokinetics-of-a-transdermal-fentanyl-solution-in-suffolk-sheep-ovis-aries
#11
Kimberly Y Jen, Melissa C Dyson, Patrick A Lester, Jean A Nemzek
Sheep used as surgical models require appropriate pain management, and the commonly used transdermal fentanyl patches require a long predosing period to achieve adequate plasma concentrations. The aim of this study was to assess the pharmacokinetic parameters of an FDA-approved transdermal fentanyl solution (TFS) that has yet to be tested in sheep. In this study, we compared TFS at 2.7 mg/kg (n = 2), 1.7 mg/kg (n = 3), and 0.5 mg/kg (n = 3) with the control fentanyl patch at 2 μg/kg/h (n = 1); both products were applied topically to the intrascapular region...
September 1, 2017: Journal of the American Association for Laboratory Animal Science: JAALAS
https://www.readbyqxmd.com/read/28903499/the-long-lasting-rodenticide-brodifacoum-induces-neuropathology-in-adult-male-rats
#12
Sergey Kalinin, Natalia Marangoni, Katarzyna Kowal, Arunangsu Dey, Kinga Lis, Sergey Brodsky, Richard van Breemen, Zane Hauck, Richard Ripper, Israel Rubinstein, Guy Weinberg, Douglas L Feinstein
Superwarfarins are very long-lasting rodenticides effective in warfarin-resistant rodents at extremely low doses. The consequences of chronic superwarfarin levels in tissues, due to biological half-lives on the order of 20 days, have not been examined. We now characterized the neurological effects of brodifacoum (BDF), one of the most widely used superwarfarins, in adult male Sprague Dawley rats. Dosing curves established the acute oral lethal dose for BDF as 221 ± 14 μg/kg. Measurement of tissue BDF levels showed accumulation throughout the body, including the central nervous system, with levels diminishing over several days...
September 1, 2017: Toxicological Sciences: An Official Journal of the Society of Toxicology
https://www.readbyqxmd.com/read/28903012/in-vitro-chondrotoxicity-of-nonsteroidal-anti-inflammatory-drugs-and-opioid-medications
#13
Geoffrey D Abrams, Wenteh Chang, Jason L Dragoo
BACKGROUND: A variety of medications are administered to the intra-articular space for the relief of joint pain. While amide-type local anesthetics have been extensively studied, there is minimal information regarding the potential chondrotoxicity of nonsteroidal anti-inflammatory drugs (NSAIDs) and opioid medications. PURPOSE: To investigate the in vitro chondrotoxicity of single-dose equivalent concentrations of ketorolac, morphine, meperidine, and fentanyl on human chondrocytes...
September 1, 2017: American Journal of Sports Medicine
https://www.readbyqxmd.com/read/28902987/understanding-reduction-kinetics-of-aqueous-vanadium-v-and-transformation-products-using-rotating-ring-disk-electrode
#14
Gongde Chen, Haizhou Liu
Vanadium(V) is an emerging contaminant in the most recent EPA's candidate contaminant list (CCL4). The redox chemistry of vanadium controls its occurrence in the aquatic environment, but the impact of vanadium(V) speciation on its redox properties remains largely unknown. This study developed electrochemical techniques with a rotating ring disk electrode to examine the reduction kinetics of four pH-dependent vanadium(V) species in the presence and absence of phosphate. Results showed that the reduction of VO2+, HxV4O12+x(4+x)- (V4) and HVO42- proceeded via a one-electron transfer, while the reduction of NaxHyV10O28(6-x-y)- (V10) underwent a two-electron transfer process...
September 13, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28898162/modulation-of-protein-a-binding-allows-single-step-purification-of-mouse-bispecific-antibodies-that-retain-fcrn-binding
#15
Adam Zwolak, Anthony A Armstrong, Susan H Tam, Jose R Pardinas, Dennis R Goulet, Songmao Zheng, Kerry Brosnan, Eva Emmell, Jeffrey Luo, Gary L Gilliland, Mark L Chiu
The increased number of bispecific antibodies (BsAb) under therapeutic development has resulted in a need for mouse surrogate BsAbs. Here, we describe a one-step method for generating highly pure mouse BsAbs suitable for in vitro and in vivo studies. We identify two mutations in the mouse IgG2a and IgG2b Fc region: one that eliminates protein A binding and one that enhances protein A binding by 8-fold. We show that BsAbs harboring these mutations can be purified from the residual parental monoclonal antibodies in one step using protein A affinity chromatography...
September 12, 2017: MAbs
https://www.readbyqxmd.com/read/28895852/gene-therapy-for-hemophilia
#16
REVIEW
Amit C Nathwani, Andrew M Davidoff, Edward G D Tuddenham
The best currently available treatments for hemophilia A and B (factor VIII or factor IX deficiency, respectively) require frequent intravenous infusion of highly expensive proteins that have short half-lives. Factor levels follow a saw-tooth pattern that is seldom in the normal range and falls so low that breakthrough bleeding occurs. Most hemophiliacs worldwide do not have access to even this level of care. In stark contrast, gene therapy holds out the hope of a cure by inducing continuous endogenous expression of factor VIII or factor IX following transfer of a functional gene to replace the hemophilic patient's own defective gene...
October 2017: Hematology/oncology Clinics of North America
https://www.readbyqxmd.com/read/28893773/colistin-is-extensively-lost-during-standard-in-vitro-experimental-conditions
#17
Matti Karvanen, Christer Malmberg, Pernilla Lagerbäck, Lena E Friberg, Otto Cars
Colistin adheres to a range of materials, including plastics in labware. The loss caused by adhesion influences an array of methods detrimentally, including MIC assays and in vitro time-kill experiments. The aim of this study was to characterize the extent and time course of colistin loss in different types of laboratory materials during a simulated time-kill experiment without bacteria or plasma proteins present.Three types of commonly used large test tubes were studied: soda-lime glass, polypropylene and polystyrene, as well as two different polystyrene microplates and low protein binding microtubes...
September 11, 2017: Antimicrobial Agents and Chemotherapy
https://www.readbyqxmd.com/read/28892517/naturally-acquired-antibody-responses-to-more-than-300-plasmodium-vivax-proteins-in-three-geographic-regions
#18
Rhea J Longley, Michael T White, Eizo Takashima, Masayuki Morita, Bernard N Kanoi, Connie S N Li Wai Suen, Inoni Betuela, Andrea Kuehn, Piyarat Sripoorote, Camila T Franca, Peter Siba, Leanne J Robinson, Marcus Lacerda, Jetsumon Sattabongkot, Takafumi Tsuboi, Ivo Mueller
Plasmodium vivax remains an important cause of malaria in South America and the Asia-Pacific. Naturally acquired antibody responses against multiple P. vivax proteins have been described in numerous countries, however, direct comparison of these responses has been difficult with different methodologies employed. We measured antibody responses against 307 P. vivax proteins at the time of P. vivax infection, and at 2-3 later time-points in three countries. We observed that seropositivity rates at the time of infection were highest in Thailand, followed by Brazil then PNG, reflecting the level of antigenic input...
September 11, 2017: PLoS Neglected Tropical Diseases
https://www.readbyqxmd.com/read/28887124/impaired-insulin-signaling-upon-loss-of-ovarian-function-is-associated-with-a-reduction-of-tristetraprolin-and-an-increased-stabilization-of-chemokine-in-adipose-tissue
#19
Eun-Kyung Choi, Monisha Rajasekaran, Ok-Joo Sul, Yeonsoo Joe, Hyun-Taeg Chung, Rina Yu, Hye-Seon Choi
Loss of ovarian function can activate inflammation and lead to insulin resistance (IR). IR is also a core feature of obesity and obesity-associated metabolic dysfunction. Tristetraprolin/zinc finger protein 36 (TTP) interferes with TNF-α production by destabilizing TNF-α mRNA, and mice deficient in TTP develop a complex syndrome of inflammatory disease (Carballo et al., 1998; Taylor et al., 1999). We hypothesized that ovariectomy (OVX) might also prime inflammation by reducing tristetraprolin/zinc finger protein 36 (TTP) levels...
September 5, 2017: Molecular and Cellular Endocrinology
https://www.readbyqxmd.com/read/28880210/comparative-pharmacokinetic-study-for-linezolid-and-two-novel-antibacterial-oxazolidinone-derivatives-in-rabbits-can-differences-in-the-pharmacokinetic-properties-explain-the-discrepancies-between-their-in-vivo-and-in-vitro-antibacterial-activities
#20
Mohsen A Hedaya, Vidhya Thomas, Mohamed E Abdel-Hamid, Elijah O Kehinde, Oludotun A Phillips
This is a comparative pharmacokinetics study of linezolid (Lzd), and two novel oxazolidinone antibacterial agents-PH027 and PH051-in rabbits to determine if the discrepancy between the in vitro and in vivo activities of the novel compounds is due to pharmacokinetic factors. The pharmacokinetics after IV and oral administration, plasma protein binding and tissue distribution for the three compounds were compared. The elimination half-lives were 52.4 ± 6.3, 68.7 ± 12.1 and 175 ± 46.1 min for Lzd, PH027 and PH051, respectively...
September 7, 2017: Pharmaceutics
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