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https://www.readbyqxmd.com/read/29679940/nmr-based-metabolic-toxicity-of-low-level-hg-exposure-to-earthworms
#1
Ronggui Tang, Changfeng Ding, Fei Dang, Yibing Ma, Junsong Wang, Taolin Zhang, Xingxiang Wang
Mercury is a globally distributed toxicant to aquatic animals and mammals. However, the potential risks of environmental relevant mercury in terrestrial systems remain largely unclear. The metabolic profiles of the earthworm Eisenia fetida after exposure to soil contaminated with mercury at 0.77 ± 0.09 mg/kg for 2 weeks were investigated using a two-dimensional nuclear magnetic resonance-based (1 H-13 C NMR) metabolomics approach. The results revealed that traditional endpoints (e.g., mortality and weight loss) did not differ significantly after exposure...
April 18, 2018: Environmental Pollution
https://www.readbyqxmd.com/read/29679901/replacement-of-arg-with-nle-and-modified-d-phe-in-the-core-sequence-of-mshs-ac-his-d-phe-arg-trp-nh-2-leads-to-hmc1r-selectivity-and-pigmentation
#2
Saghar Mowlazadeh Haghighi, Yang Zhou, Jixun Dai, Jonathon R Sawyer, Victor J Hruby, Minying Cai
Melanoma skin cancer is the fastest growing cancer in the US [1]. A great need exists for improved formulations and mechanisms to prevent and protect human skin from cancers and other skin damage caused by sunlight exposure. Current efforts to prevent UV damage to human skin, which in many cases leads to melanoma and other skin cancers. The primordial melanocortin-1 receptor (MC1R) is involved in regulating skin pigmentation and hair color, which is a natural prevention from UV damage. The endogenous melanocortin agonists induce pigmentation and share a core pharmacophore sequence "His-Phe-Arg-Trp", and it was found that substitution of the Phe by D-Phe results in increasing melanocortin receptor potency...
April 11, 2018: European Journal of Medicinal Chemistry
https://www.readbyqxmd.com/read/29679876/coriariin-m-a-trimeric-hydrolysable-tannin-with-dehydrodigalloyl-and-valoneoyl-groups-as-linking-units-and-accompanying-dimeric-hydrolysable-tannins-from-coriaria-japonica
#3
Yuuki Shimozu, Takayasu Hirai, Tsutomu Hatano
Three oligomeric hydrolysable tannins, coriariins K, L, and M, which were previously undescribed, together with five known hydrolysable tannins were isolated from dried leaves of Coriaria japonica. Their structures were determined based on 1D and 2D NMR spectroscopy, HR-ESI-MS, and ECD spectroscopy experiments. Among the isolated compounds, coriariin M has a unique trimer structure where both dehydrodigalloyl and valoneoyl group linkages were found between the hydrolysable tannin monomers. Dimeric hydrolysable tannins coriariins K and L, having a dehydrodigalloyl group as the linking unit, were structurally related to coriariin A, the main hydrolysable tannin of this plant species...
April 18, 2018: Phytochemistry
https://www.readbyqxmd.com/read/29679875/impurity-profiling-of-varenicline-tartrate-by-lc-qtof-mass-spectrometric-techniques-during-drug-development
#4
Yuting Lu, Xiyang Sun, Fan Song, Lei Wang, Min Song, Taijun Hang
An LC-QTOF-MS method was developed for the separation and characterization of related substances in varenicline tartrate. The separation was established on an InertSustain C18 column (4.6 mm × 150 mm, 5 μm) by liner gradient elution using 0.05% trifluoroacetic acid as mobile phase A and acetonitrile as mobile phase B. The degradation studies were conducted under the ICH prescribed stress conditions. Varenicline tartrate was found to be unstable to alkaline, oxidative, thermal and photolytic stresses, while relatively stable under acid stress condition...
April 3, 2018: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/29679841/-1-h-line-width-dependence-on-mas-speed-in-solid-state-nmr-comparison-of-experiment-and-simulation
#5
Ulrich Sternberg, Raiker Witter, Ilya Kuprov, Jonathan M Lamley, Andres Oss, Józef R Lewandowski, Ago Samoson
Recent developments in magic angle spinning (MAS) technology permit spinning frequencies of ≥100 kHz. We examine the effect of such fast MAS rates upon nuclear magnetic resonance proton line widths in the multi-spin system of β-Asp-Ala crystal. We perform powder pattern simulations employing Fokker-Plank approach with periodic boundary conditions and 1 H-chemical shift tensors calculated using the bond polarization theory. The theoretical predictions mirror well the experimental results. Both approaches demonstrate that homogeneous broadening has a linear-quadratic dependency on the inverse of the MAS spinning frequency and that, at the faster end of the spinning frequencies, the residual spectral line broadening becomes dominated by chemical shift distributions and susceptibility effects even for crystalline systems...
April 7, 2018: Journal of Magnetic Resonance
https://www.readbyqxmd.com/read/29679649/protein-solvent-interfaces-in-human-y145stop-prion-protein-amyloid-fibrils-probed-by-paramagnetic-solid-state-nmr-spectroscopy
#6
Darryl Aucoin, Yongjie Xia, Theint Theint, Philippe S Nadaud, Krystyna Surewicz, Witold K Surewicz, Christopher P Jaroniec
The C-terminally truncated Y145Stop variant of prion protein (PrP23-144), which is associated with heritable PrP cerebral amyloid angiopathy in humans and also capable of triggering a transmissible prion disease in mice, serves as a useful in vitro model for investigating the molecular and structural basis of amyloid strains and cross-seeding specificities. Here, we determine the protein-solvent interfaces in human PrP23-144 amyloid fibrils generated from recombinant 13 C,15 N-enriched protein and incubated in aqueous solution containing paramagnetic Cu(II)-EDTA, by measuring residue-specific 15 N longitudinal paramagnetic relaxation enhancements using two-dimensional magic-angle spinning solid-state NMR spectroscopy...
April 18, 2018: Journal of Structural Biology
https://www.readbyqxmd.com/read/29679407/longitudinal-urinary-metabolomic-profiling-reveals-metabolites-for-asthma-development-in-early-childhood
#7
Chih-Yung Chiu, Gigin Lin, Mei-Ling Cheng, Meng-Han Chiang, Ming-Han Tsai, Kuan-Wen Su, Man-Chin Hua, Sui-Ling Liao, Shen-Hao Lai, Tsung-Chieh Yao, Kuo-Wei Yeh, Jing-Long Huang
BACKGROUND: Several metabolites and altered metabolic pathways have been reported to be associated with asthma. However, longitudinal analysis of the dynamics of metabolites contributing to the development of asthma has not yet been fully clarified. METHODS: We sought to identify the metabolic mechanisms underlying asthma development in early childhood. Thirty children with asthma and paired healthy controls from a prospective birth cohort were enrolled. Time-series analysis of urinary metabolites collected at ages 1, 2, 3, and 4 years were assessed using 1 H-nuclear magnetic resonance (NMR) spectroscopy coupled with partial least-squares discriminant analysis (PLS-DA)...
April 21, 2018: Pediatric Allergy and Immunology
https://www.readbyqxmd.com/read/29679394/advances-in-the-cellular-structural-biology-of-nucleic-acids
#8
REVIEW
Ilektra-Chara Giassa, Jan Rynes, Tomas Fessl, Silvie Foldynova-Trantirkova, Lukas Trantirek
Conventional biophysical and chemical biology approaches for delineating relationships between the structure and biological function of nucleic acids (NAs) abstract NAs from their native biological context. However, cumulative experimental observations have revealed that the structure, dynamics and interactions of NAs might be strongly influenced by a broad spectrum of specific and non-specific physical-chemical environmental factors. This consideration has recently sparked interest in the development of novel tools for structural characterization of NAs in the native cellular context...
April 21, 2018: FEBS Letters
https://www.readbyqxmd.com/read/29679218/targeting-matrix-metalloproteinases-with-novel-diazepine-substituted-cinnamic-acid-derivatives-design-synthesis-in-vitro-and-in-silico-studies
#9
Dharmender Rathee, Viney Lather, Ajmer Singh Grewal, Harish Dureja
Lung cancer is the notable cause of cancer associated deaths worldwide. Recent studies revealed that the expression of matrix metalloproteinases (MMPs) is extremely high in lung tumors compared with non-malignant lung tissue. MMPs (-2 and -9) play an important part in tumor development and angiogenesis, which suggests that creating potent MMP-2 and -9 inhibitors, should be an important goal in lung cancer therapy. In the present study, an effort has been made to develop new anti-metastatic and anti-invasive agents, wherein a series of novel diazepine substituted cinnamic acid derivatives were designed, synthesized and assayed for their inhibitory activities on MMP-2 and MMP-9...
April 20, 2018: Chemistry Central Journal
https://www.readbyqxmd.com/read/29679041/a-new-protein-tyrosine-phosphatase-1b-inhibitory-%C3%AE-pyrone-type-polyketide-from-okinawan-plant-associated-aspergillus-sp-tmpu1623
#10
Hiroyuki Yamazaki, Kenta Takahashi, Natsuki Iwakura, Tatsuki Abe, Masanari Akaishi, Satomi Chiba, Michio Namikoshi, Ryuji Uchida
A new polyenyl-α-pyrone polyketide, aspopyrone A (1), was isolated from a culture broth of Okinawan plant-associated Aspergillus sp. TMPU1623 by solvent extraction, ODS column chromatography, and preparative HPLC (ODS). The structure of 1 was assigned based on NMR experiments. Compound 1 exhibited protein tyrosine phosphatase (PTP) 1B and T-cell PTP (TCPTP) inhibitory activities with IC50 values of 6.7 and 6.0 μM, respectively.
April 20, 2018: Journal of Antibiotics
https://www.readbyqxmd.com/read/29678776/comparison-of-the-3d-structures-of-mouse-and-human-%C3%AE-synuclein-fibrils-by-solid-state-nmr-and-stem
#11
Songhwan Hwang, Pascal Fricke, Maximilian Zinke, Karin Giller, Joseph S Wall, Dietmar Riedel, Stefan Becker, Adam Lange
Intra-neuronal aggregation of α-synuclein into fibrils is the molecular basis for α -synucleinopathies, such as Parkinson's disease. The atomic structure of human α -synuclein (hAS) fibrils was recently determined by Tuttle et al. using solid-state NMR (ssNMR). The previous study found that hAS fibrils are composed of a single protofilament. Here, we have investigated the structure of mouse α -synuclein (mAS) fibrils by STEM and isotope-dilution ssNMR experiments. We found that in contrast to hAS, mAS fibrils consist of two or even three protofilaments which are connected by rather weak interactions in between them...
April 17, 2018: Journal of Structural Biology
https://www.readbyqxmd.com/read/29678734/polymeric-micelle-mediated-delivery-of-half-sandwich-ruthenium-ii-complexes-with-phosphanes-derived-from-fluoroloquinolones-for-lung-adenocarcinoma-treatment
#12
Przemysław Kołoczek, Agnieszka Skórska-Stania, Agnieszka Cierniak, Victor Sebastian, Urszula K Komarnicka, Michał Płotek, Agnieszka Kyzioł
Novel half-sandwich ruthenium(II) complexes with aminomethyl(diphenyl)phosphine derived from fluoroloquinolones (RuPCp, RuPSf, RuPLm, RuPNr) were being investigated as alternatives to well-established metal-based chemotherapeutics. All compounds were characterized by elemental analysis, selected spectroscopic methods (i.e., absorption and fluorescence spectroscopy, ESI-MS, NMR, circular dichroizm), X-ray diffractometry, ICP-MS, and electrochemical techniques. To overcome low solubility, serious side effects connected with systemic cytotoxicity of ruthenium complexes, and acquiring the resistance of cancer cells, polymeric nanoformulations based on Pluronic P-123 micelles loaded with selected Ru(II) complexes were prepared and characterized...
April 17, 2018: European Journal of Pharmaceutics and Biopharmaceutics
https://www.readbyqxmd.com/read/29678593/characterisation-of-aptamer-bc-007-substance-and-product-using-circular-dichroism-and-nuclear-magnetic-resonance-spectroscopy
#13
Hardy Weisshoff, Katrin Wenzel, Sarah Schulze-Rothe, Heike Nikolenko, Hanna Davideit, Niels-Peter Becker, Peter Göttel, G Susan Srivatsa, Margitta Dathe, Johannes Müller, Annekathrin Haberland
Possible unwanted folding of biopharmaceuticals during manufacturing and storage has resulted in analysis schemes compared to small molecules that includes bioanalytical characterisation besides chemical characterisation. Whether bioanalytical characterisation is required for nucleotide-based drugs, may be decided on a case-by-case basis. Nucleotide-based pharmaceuticals, if chemically synthesised, occupy an intermediate position between small-molecule drugs and biologics. Here, we tested whether a physicochemical characterisation of a nucleotide-based drug substance, BC 007, was adequate, using circular dichroism (CD) spectroscopy...
April 17, 2018: Journal of Pharmaceutical Sciences
https://www.readbyqxmd.com/read/29678461/design-synthesis-evaluation-and-molecular-docking-of-ursolic-acid-derivatives-containing-a-nitrogen-heterocycle-as-anti-inflammatory-agents
#14
Zhi-Yu Wei, Ke-Qiang Chi, Ke-Si Wang, Jie Wu, Li-Ping Liu, Hu-Ri Piao
Ursolic acid derivatives containing oxadiazole, triazolone, and piperazine moieties were synthesized in an attempt to develop potent anti-inflammatory agents. Structures of the synthesized compounds were elucidated by 1 H NMR, 13 C NMR, and HRMS. Most of the synthesized compounds showed pronounced anti-inflammatory effects at 100 mg/kg. In particular, compound 11b, which displayed the most potent anti-inflammatory activity of all of the compounds prepared, with 69.76% inhibition after intraperitoneal administration, was more potent than the reference drugs indomethacin and ibuprofen...
April 11, 2018: Bioorganic & Medicinal Chemistry Letters
https://www.readbyqxmd.com/read/29678351/clinical-and-inflammatory-phenotyping-can-electronic-nose-and-nmr-based-metabolomics-work-at-the-bedside
#15
Mauro Maniscalco, Andrea Motta
Electronic nose (eNose) and nuclear magnetic resonance (NMR)-based metabolomics seem to be able to identify metabolic and inflammatory profiles in patients with chronic obstructive diseases. The hypothesis arises from three recent studies using two different methods in patients with asthma and chronic obstructive pulmonary diseases (COPD), opening promising diagnostic perspectives. The possibility that the use of eNose and NMR-based metabolomics might provide clinical/inflammatory characteristics is intriguing...
April 17, 2018: Archives of Medical Research
https://www.readbyqxmd.com/read/29678198/metabolic-retroconversion-of-trimethylamine-n-oxide-and-the-gut-microbiota
#16
Lesley Hoyles, Maria L Jiménez-Pranteda, Julien Chilloux, Francois Brial, Antonis Myridakis, Thomas Aranias, Christophe Magnan, Glenn R Gibson, Jeremy D Sanderson, Jeremy K Nicholson, Dominique Gauguier, Anne L McCartney, Marc-Emmanuel Dumas
BACKGROUND: The dietary methylamines choline, carnitine, and phosphatidylcholine are used by the gut microbiota to produce a range of metabolites, including trimethylamine (TMA). However, little is known about the use of trimethylamine N-oxide (TMAO) by this consortium of microbes. RESULTS: A feeding study using deuterated TMAO in C57BL6/J mice demonstrated microbial conversion of TMAO to TMA, with uptake of TMA into the bloodstream and its conversion to TMAO. Microbial activity necessary to convert TMAO to TMA was suppressed in antibiotic-treated mice, with deuterated TMAO being taken up directly into the bloodstream...
April 20, 2018: Microbiome
https://www.readbyqxmd.com/read/29677794/synthesis-and-properties-of-fluorinated-styrene-copolymers-as-antibiofouling-coatings
#17
Jong-Woon Ha, Hea Jung Park, Junhoo Park, Inwon Lee, Hyun Park, Hoyoul Kong, Jong Mok Park, Do-Hoon Hwang
A series of polystyrene (PS) copolymers containing 2,3,4,5,6-pentafluorostyrene units with different monomer ratios were prepared for antifouling applications. PS, poly(styrene-co-pentafluorostyrene) (poly(S-co-FS)), and poly(pentafluorostyrene) (PFS) were synthesized by free-radical polymerization and characterized by 1H NMR, Fourier-transform infrared spectroscopy, and gel permeation chromatography. The surface energy of the polymer films decreased with increasing content of fluorinated styrene. Protein adsorption experiments were carried out on the synthesized polymer films using fluorescein isothiocyanate-labeled bovine serum albumin as a fluorescent protein...
September 1, 2018: Journal of Nanoscience and Nanotechnology
https://www.readbyqxmd.com/read/29677644/antimicrobial-activity-and-cytotoxicity-of-xanthoquinodin-analogs-from-the-fungus-cytospora-eugeniae-bcc42696
#18
Karoon Sadorn, Siriporn Saepua, Nattawut Boonyuen, Tanapong Boonruangprapa, Pranee Rachtawee, Pattama Pittayakhajonwut
Eleven previously undescribed compounds, including cytosporanthraxanthone, xanthoquinodins A7-A10, ketoxanthoquinodin A6, xanthoquinodins B6-B8, and spiroxanthoquinodins A and B, and one synthetically known compound, 2-methoxy pinselin, as well as ten known compounds, including xanthoquinodins A4-A6, B4, and B5, chrysophanol, physcion, (4S)-5-hydroxy-4-methoxy-α-tetralone, (4S)-4,8-dihydroxy-α-tetralone (or isosclerone), and gonytolide C were isolated from the fungus Cytospora eugeniae BCC42696. Their chemical structures were determined based on the analysis of NMR spectroscopic and mass spectrometric data...
April 17, 2018: Phytochemistry
https://www.readbyqxmd.com/read/29677643/biotransformation-of-cyclocanthogenol-by-the-endophytic-fungus-alternaria-eureka-1e1bl1
#19
Güner Ekiz, Seda Duman, Erdal Bedir
The microbial transformation of cyclocanthogenol (CCG), Astragalus sp. originated sapogenin, by the endophytic fungus Alternaria eureka 1E1BL1 isolated from Astragalus angustifolius was investigated. Hydroxylation, oxidation, epoxidation, O-methylation, ring-expansion and methyl migration reactions were observed on the triterpenoid skeleton. As a result, eight metabolites were isolated and the structures of the previously undescribed compounds were established by 1-D, 2-D NMR and HR-MS analyses.
April 17, 2018: Phytochemistry
https://www.readbyqxmd.com/read/29677628/circulating-metabolomic-profile-can-predict-dyslipidemia-in-hiv-patients-undergoing-antiretroviral-therapy
#20
Esther Rodríguez-Gallego, Josep Gómez, Pere Domingo, Sara Ferrando-Martínez, Joaquim Peraire, Consuelo Viladés, Sergi Veloso, Miguel López-Dupla, Raúl Beltrán-Debón, Verónica Alba, Montserrat Vargas, Alfonso J Castellano, Manuel Leal, Yolanda María Pacheco, Ezequiel Ruiz-Mateos, Félix Gutiérrez, Francesc Vidal, Anna Rull
BACKGROUND AND AIMS: Dyslipidemia in HIV-infected patients is unique and pathophysiologically associated with host factors, HIV itself and the use of antiretroviral therapy (ART). The use of nuclear magnetic resonance spectroscopy (NMR) provides additional data to conventional lipid measurements concerning the number of lipoprotein subclasses and particle sizes. METHODS: To investigate the ability of lipoprotein profile, we used a circulating metabolomic approach in a cohort of 103 ART-naive HIV-infected patients, who were initiating non-nucleoside analogue transcriptase inhibitor (NNRTI)-based ART, and we subsequently followed up these patients for 36 months...
April 9, 2018: Atherosclerosis
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