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Carey Vana Rynjah, Ningthoujam Neelima Devi, Nasheman Khongthaw, Donkupar Syiem, Suktilang Majaw
The present study was designed to evaluate the antidiabetic potential of the aqueous leaves extract of Zanthoxylum armatum DC. leaves using in vivo and in vitro approaches. For in vivo studies, blood glucose level was monitored at different intervals after administration of varying doses of the extract for its hypoglycemic (100-6000 mg/kg b.w.) and antihyperglycemic (250 mg/kg b.w.) effect in normoglycemic and diabetic mice. In vitro enzymatic inhibition activity was tested against α-amylase, α- and β-glucosidase and lipase...
January 2018: Journal of Traditional and Complementary Medicine
K S Koch, T Moran, W T Shier, H L Leffert
N-acetyl-2-aminofluorene (AAF) is a procarcinogen used widely in physiological investigations of chemical hepatocarcinogenesis. Its metabolic pathways have been described extensively, yet little is known about its biochemical processing, growth cycle expression and pharmacological properties inside living hepatocytes - the principal cellular targets of this hepatocarcinogen. In this report, primary monolayer adult rat hepatocyte cultures and high specific-activity [ring G-3H]-N-acetyl-2-aminofluorene were used to extend previous observations of metabolic activation of AAF by highly differentiated, proliferation-competent hepatocytes in long-term cultures...
January 8, 2018: Toxicological Sciences: An Official Journal of the Society of Toxicology
Vanessa Vega-García, Adelaida Díaz-Vilchis, Juan-Pablo Saucedo-Vázquez, Alejandro Solano-Peralta, Enrique Rudiño-Piñera, Wilhelm Hansberg
CAT-2, a cytosolic catalase-peroxidase (CP) from Neurospora crassa, which is induced during asexual spore formation, was heterologously expressed and characterized. CAT-2 had the Met-Tyr-Trp adduct required for catalase activity. Its KM for H2O2 was micromolar for peroxidase and millimolar for catalase activity. A Em = -158 mV reduction potential value was obtained and the Soret band shift suggested a mixture of low and high spin ferric iron. CAT-2 EPR spectrum at 10 K indicated an axial and a rhombic component...
January 2, 2018: Archives of Biochemistry and Biophysics
Maja Karaman, Ljiljana Janjušević, Dragica Jakovljević, Filip Šibul, Boris Pejin
This study outlines antioxidant and anti-AChE activities of the polysaccharide (PSH) extract from the mushroom species Amanita strobiliformis. Both the presence of α and ß glucans within the aforementioned extract was recorded. PSH extract displayed a profound scavenging activity of OH radicals (IC50 value, 11.86 ± 0.59 μg/mL) and high potential for reduction of Fe3+ ions (174.11 ± 8.70 mg eq. AA/g d.w.) being almost 48- and 5-fold more effective than mannitol and butylated hydroxytoluene used as a positive control, respectively...
January 2, 2018: Natural Product Research
Chin W Yong, Ilian T Todorov
The DL_ANALYSER Notation for Atomic Interactions, DANAI, is the notation syntax to describe interactions between molecules. This notation can annotate precisely the detailed atomistic interactions without having to resolve to diagrammatic illustrations, and yet can be interpreted easily by both human users and computational means. By making use of the DL_F Notation, a universal atom typing scheme for molecular simulations, DANAI contains the expression of atomic species in a natural chemical sense. It is implemented within DL_ANALYSER, a general analysis software program for DL_POLY molecular dynamics simulation software...
December 24, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Ala Bunescu, Trevor W Butcher, John F Hartwig
We report the silylation of primary C-H bonds located β to secondary and tertiary alcohols by exploiting perfluorinated esters as traceless directing groups. The conversion of a sec-ondary or tertiary alcohol to a perfluoroalkyl ester and conver-sion of the ester to the corresponding silyl acetals by hydrosi-lylation allows for selective β-C(sp3)-H silylation catalyzed by the combination of [Ir(cod)OMe]2 and Me4Phen (3,4,7,8-tetramethyl-1,10-phenanthroline) to form 6-membered ox-asilolanes. Tamao-Fleming oxidation of these oxasilolanes leads to 1,2 diols...
December 28, 2017: Journal of the American Chemical Society
Mohamed M Aboelnga, John J Hayward, James W Gauld
Archaeal threonyl-tRNA synthetase (ThrRS) possesses an editing active site wherein tRNAThr that has been misaminoacylated with serine (i.e., Ser-tRNAThr) is hydrolytically cleaved to serine and tRNAThr. It has been suggested that the free ribose sugar hydroxyl of Ado76 of the tRNAThr (Ado762'OH) is the mechanistic base, promoting hydrolysis by orienting a nucleophilic water near the scissile Ser-tRNAThr ester bond. We have performed a computational study, involving Molecular Dynamics (MD) and hybrid ONIOM Quantum Mechanics/Molecular Mechanics (QM/MM) methods, considering all possible editing mechanisms in order to gain an understanding of the role played by Ado762'OH group...
December 27, 2017: Journal of Physical Chemistry. B
Douglas J Marcotte, Jean-Christophe Hus, Charles C Banos, Craig Wildes, Robert Arduini, Chris Bergeron, Catherine A Hession, Darren P Baker, Edward Lin, Kevin M Guckian, Anthone W Dunah, Laura F Silvian
The membrane protein interacting with kinase C1 (PICK1) plays a trafficking role in the internalization of neuron receptors such as the amino-3-hydroxyl-5-methyl-4-isoxazole-propionate (AMPA) receptor. Reduction of surface AMPA type receptors on neurons reduces synaptic communication leading to cognitive impairment in progressive neurodegenerative diseases such as Alzheimer disease. The internalization of AMPA receptors is mediated by the PDZ domain of PICK1 which binds to the GluA2 subunit of AMPA receptors and targets the receptor for internalization through endocytosis, reducing synaptic communication...
December 27, 2017: Protein Science: a Publication of the Protein Society
Arnold Donkor Forkuo, Charles Ansah, David Pearson, Werner Gertsch, Amanda Cirello, Adam Amaral, Jaimie Spear, Colin W Wright, Caroline Rynn
BACKGROUND: This study aims at characterizing the in vitro metabolism of cryptolepine using human and rat hepatocytes, identifying metabolites in rat plasma and urine after a single cryptolepine dose, and evaluating the single-dose oral and intravenous pharmacokinetics of cryptolepine in male Sprague Dawley (SD) rats. METHODS: The in vitro metabolic profiles of cryptolepine were determined by LC-MS/MS following incubation with rat and human hepatocytes. The in vivo metabolic profile of cryptolepine was determined in plasma and urine samples from Sprague Dawley rats following single-dose oral administration of cryptolepine...
December 22, 2017: BMC Pharmacology & Toxicology
Stefan W Toennes, Anna Geraths, Werner Pogoda, Alexander Paulke, Cora Wunder, Eef L Theunissen, Johannes G Ramaekers
Each year, synthetic cannabinoids are occurring in high numbers on the illicit drug market but data obtained after controlled application are rare. The present study on pharmacokinetics in urine is part of a pilot study on adverse effects of JWH-018, which is one of the oldest and best known synthetic cannabinoids. Six subjects inhaled smoke from 2 and 3mg JWH-018. The drug and ten potential metabolites were analyzed in urine samples collected during 12h after inhalation by liquid chromatography-mass spectrometry (LC-MS/MS) without and with conjugate cleavage...
December 9, 2017: Journal of Pharmaceutical and Biomedical Analysis
Lena Trotochaud, Ashley R Head, Sven Pletincx, Osman Karslıoğlu, Yi Yu, Astrid Waldner, Line Kyhl, Tom Hauffman, Herman Terryn, Bryan W Eichhorn, Hendrik Bluhm
We use ambient pressure X-ray photoelectron spectroscopy (APXPS) to study chemical changes, including hydroxylation and water adsorption, at copper oxide surfaces from ultra-high vacuum to ambient relative humidities of ~5%. Polycrystalline CuO and Cu2O surfaces were prepared by selective oxidation of metallic copper foils. For both oxides, hydroxylation occurs readily, even at high vacuum conditions. Hydroxylation on both oxides plateaus near ~0.01% relative humidity (RH) at a coverage of ~1 monolayer. In contrast to previous studies, neither oxide shows significant accumulation of molecular water; rather, both surfaces show a high affinity for adventitious carbon contaminants...
December 7, 2017: Journal of Physical Chemistry. B
H K Shin, K Y Kim, J W Park, K T No
Computational approaches have been suggested as an informative tool for risk assessment of nanomaterials. Nano (quantitative) structure-activity relationship, nano-(Q)SAR, models have been developed to predict toxicity of metal oxide (MOx) nanoparticles (NPs); however, the packing structure and cluster of nanoparticle have been included for the descriptor calculation in only two studies. This study proposed spherical cluster and hydroxyl metal coordination complex to calculate descriptors for development of nanoparticle cytotoxicity classification model...
November 30, 2017: SAR and QSAR in Environmental Research
Nina Beyer, Justyna K Kulig, Marco W Fraaije, Martin A Hayes, Dick Janssen
The conversion of a series of pharmaceutical compounds was examined with three variants of cytochrome P450BM3 fused to phosphite dehydrogenase to enable cofactor recycling. Conditions for enzyme production were optimized and the purified PTDH-P450BM3 variants were tested against 32 commercial drugs using rapid UPLC-MS analysis. The sets of mutations (R47L/F87V/L188Q and R47L/F87V/L188Q/E267V/G415S) improved conversion for all compounds and a variety of products were detected. Product analysis showed that reaction types included C-hydroxylation, N-oxidation, demethylation, and aromatization...
November 27, 2017: Chembiochem: a European Journal of Chemical Biology
Nisansala Ganewatta, Ziad El Rassi
Two types of monolithic stationary phases with incorporated hydroxyl functionalized multiwalled carbon nanotubes (OH-MWCNTs) were introduced and evaluated, namely, the poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate) monolith, denoted as poly(GMA-co-EDMA), and a diol derivative of the poly(GMA-co-EDMA) monolith. The diol derivative monolith was obtained by subjecting the poly(GMA-co-EDMA) monolith with physically incorporated OH-MWCNTs to an acid treatment with 0.1 M sulfuric acid at a moderate temperature of 50 °C for a total of 7...
November 28, 2017: Analyst
David W Hein, Xiaoyan Zhang, Mark A Doll
Arylamine N-acetyltransferase 1 (NAT1) and 2 (NAT2) catalyze the acetylation of arylamine carcinogens. Single nucleotide polymorphisms in the NAT2 coding exon present in NAT2 haplotypes encode allozymes with reduced N-acetyltransferase activity towards the N-acetylation of arylamine carcinogens and the O-acetylation of their N-hydroxylated metabolites. NAT2 acetylator phenotype modifies urinary bladder cancer risk following exposures to arylamine carcinogens such as 4-aminobiphenyl. 4, 4'-methylene bis (2-chloroaniline) (MOCA) is a Group 1 carcinogen for which a role of the NAT2 acetylation polymorphism on cancer risk is unknown...
November 24, 2017: Toxicology Letters
Klaus W Lange, Shiming Li
Resveratrol is a natural phytoestrogen with neuroprotective properties. Polyphenolic compounds including resveratrol exert in vitro antioxidant, anti-inflammatory, and antiamyloid effects. Resveratrol and its derivative pterostilbene are able to cross the blood-brain barrier and to influence brain activity. The present short review summarizes the available evidence regarding the effects of these polyphenols on pathology and cognition in animal models and human subjects with dementia. Numerous investigations in cellular and mammalian models have associated resveratrol and pterostilbene with protection against dementia syndromes such as Alzheimer's disease (AD) and vascular dementia...
November 23, 2017: BioFactors
Gopichand Chinta, Mohane Selvaraj Coumar, Latha Periyasamy
Background: Piperine was widely used in traditional medicine for inducing sterility and abortion. Objective: To evaluate the effect of the piperine on testis of male albino rats. Materials and Methods: Adult male rats were divided into four groups (n = 12). Group I (control): Rats were given vehicle p.o. i.e. 0.5% carboxymethyl cellulose in normal saline daily for 60 days, Group II (ED): Rats received piperine at a dose of 10 mg/kg body weight (b...
October 2017: Pharmacognosy Magazine
Natela Dushukyan, Diana M Dunn, Rebecca A Sager, Mark R Woodford, David R Loiselle, Michael Daneshvar, Alexander J Baker-Williams, John D Chisholm, Andrew W Truman, Cara K Vaughan, Timothy A Haystead, Gennady Bratslavsky, Dimitra Bourboulia, Mehdi Mollapour
The serine/threonine protein phosphatase 5 (PP5) regulates multiple cellular signaling networks. A number of cellular factors, including heat shock protein 90 (Hsp90), promote the activation of PP5. However, it is unclear whether post-translational modifications also influence PP5 phosphatase activity. Here, we show an "on/off switch" mechanism for PP5 regulation. The casein kinase 1δ (CK1δ) phosphorylates T362 in the catalytic domain of PP5, which activates and enhances phosphatase activity independent of Hsp90...
November 14, 2017: Cell Reports
Jitrayut Jitonnom, Jon I Mujika, Marc W van der Kamp, Adrian J Mulholland
Creatininase catalyzes the conversion of creatinine (a biosensor for kidney function) to creatine via a two-step mechanism: water addition followed by ring opening. Water addition is common to other known cyclic amidohydrolases, but the precise mechanism for ring opening is still under debate. The proton donor in this step is either His178 or a water molecule bound to one of the metal ions, and the roles of His178 and Glu122 are unclear. Here, the two possible reaction pathways have been fully examined by means of combined quantum mechanics/molecular mechanics simulations at the SCC-DFTB/CHARMM22 level of theory...
November 21, 2017: Biochemistry
Zineb Boutamine, Oualid Hamdaoui, Slimane Merouani
Sonochemical degradation at 600 kHz of 2-phenoxyethanol (PhE), an endocrine disrupting compound, was performed in the presence of several organic additives, namely: 2-propanol, Triton X-100 and sucrose, of different volatilities to obtain detailed information on the reaction zone and the oxidation pathway of this priority emerging water contaminate. It was found that sonication at 600 kHz and 120 W completely remove PhE (10 mg L(-1)) from aerated solutions within 100 min of irradiation. Very little removal of PhE (∼7%) and low accumulation of H2O2 took place in the presence of adequate amount of 2-propanol, indicating that reaction with OH radical outside the bubble is the major degradation pathway of PhE...
March 2018: Ultrasonics Sonochemistry
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