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Shekhar Dethe, M Deepak, Amit Agarwal
BACKGROUND: Bacopa monnieri (L.) Wettst., commonly known as Brahmi, is renowned in Indian traditional system for its potent memory enhancing activity, which has been validated by various scientific studies. OBJECTIVE: The objective of this study was to understand the molecular mechanism of memory enhancing activity of BacoMind(®) (BM), a standardized extract of B. monnieri. MATERIALS AND METHODS: BM was screened in vitro in a panel of cell-free and receptor-transfected cell assays...
July 2016: Pharmacognosy Magazine
Rosario Montirosso, Livio Provenzi, Daniela Tavian, Sara Missaglia, Maria Elisabetta Raggi, Renato Borgatti
Individual variability exists in infants' socio-emotional stress regulation, in terms of behavioral response (i.e., negative emotionality) as well as magnitude and direction (i.e., increase or decrease) of hypothalamic-pituitary-adrenal (HPA) axis reactivity (i.e., salivary cortisol post-stress concentration). The catechol-O-methyltransferase polymorphism at codon 158 (COMTval158met) associates with stress regulation, but no evidence exists for infants. This study aimed to assess the association between COMTval158met and both negative emotionality and salivary cortisol reactivity to socio-emotional stress in 4-month-old infants...
October 12, 2016: Infant Behavior & Development
Hao Meng, Yuan Liu, Bruce P Lee
: Mussel adhesive moiety, catechol, has been utilized to design a wide variety of biomaterials. However, the biocompatibility and biological responses associated with the byproducts generated during the curing process of catechol has never been characterized. An in situ curable polymer model system, 4-armed polyethylene glycol polymer end-capped with dopamine (PEG-D4), was used to characterize the production of hydrogen peroxide (H2O2) during the oxidative crosslinking of catechol. Although PEG-D4 cured rapidly (under 30s), catechol continues to polymerize over several hours to form a more densely crosslinked network over time...
October 12, 2016: Acta Biomaterialia
Michelle N Servaas, Linda Geerligs, Jojanneke A Bastiaansen, Remco J Renken, Jan-Bernard C Marsman, Ilja M Nolte, Johan Ormel, André Aleman, Harriëtte Riese
Neuroticism and genetic variation in the serotonin-transporter (SLC6A4) and catechol-O-methyltransferase (COMT) gene are risk factors for psychopathology. Alterations in the functional integration and segregation of neural circuits have recently been found in individuals scoring higher on neuroticism. The aim of the current study was to investigate how genetic risk factors impact functional network organization and whether genetic risk factors moderate the association between neuroticism and functional network organization...
October 14, 2016: Brain Imaging and Behavior
Yunhao Lu, Yanzuo Dong, Xueli Li, Qiang He
The nitration and nitrosation reactions of catechol, resorcinol, and hydroquinone (0.05 mmol/L) with sodium nitrite (0.05 mmol/L) at pH 3 and 37 °C were studied by using liquid chromatography and mass spectrometry (LC-MS) and atom charge analysis, which was aimed to provide chemical insight into the nitrite-scavenging behavior of polyphenols. The 3 benzenediols showed different mechanisms to scavenge nitrite due to their differences in hydroxyl position. Catechol was nitrated with 1 NO2 group at the hydroxyl oxygen, and resorcinol was nitrosated with 2 NO groups at the C2 and C4 (or C6 ) positions of the benzene ring...
October 14, 2016: Journal of Food Science
Deqiu Xu, Yuling Su, Lili Zhao, Fancui Meng, Chang Liu, Yayuan Guan, Jiya Zhang, Jianbin Luo
Inspired by mussel-adhesion phenomena in nature, a simple, mild surface modification process was elaborated to endow the polyurethane (PU) substrate with antibacterial/antifouling properties. In the present study, polydopamine was coated directly onto polyurethane surfaces. AgNO3 was then added and absorbed onto the surface by the active catechol and amine groups of the polydopamine coating. Meanwhile, the adsorbed Ag(+) ions were reduced in situ into metallic silver nanoparticles by the "bridge" of the polydopamine coating which yielded a coating with good antimicrobial properties...
October 13, 2016: Journal of Biomedical Materials Research. Part A
Akinobu Ito, Toru Nishikawa, Shuhei Matsumoto, Hidenori Yoshizawa, Takafumi Sato, Rio Nakamura, Masakatsu Tsuji, Yoshinori Yamano
Cefiderocol (S-649266) is a novel parenteral siderophore cephalosporin conjugated with a catechol moiety at the 3(rd)-position side chain. The in vitro activity of cefiderocol against Pseudomonas aeruginosa was enhanced in the iron-depleted condition where that of ceftazidime was not affected. The monitoring of [Thiazole-(14)C]-cefiderocol revealed the increased intracellular accumulation of cefiderocol in the P. aeruginosa cells incubated under iron-depleted condition compared with those incubated under iron-sufficient condition...
October 10, 2016: Antimicrobial Agents and Chemotherapy
Elita Montanari, Arianna Gennari, Maria Pelliccia, Charlotte Gourmel, Enrique Lallana, Pietro Matricardi, Andrew J McBain, Nicola Tirelli
Nanoparticles based on hyaluronic acid (HA) are designed to deliver tannic acid (TA) as an antimicrobial agent. The presence of HA makes these particles potentially useful to target bacteria that colonize cells presenting HA membrane receptors (e.g. CD44), such as macrophages. HA bearing 3-aminophenyl boronic acid groups (HA-APBA) is reacted with TA, yielding nanoparticles with a size that decreases with decreasing HA molecular weight (e.g. 200 nm for 44 kDa, 400 nm for 737 kDa). The boronate esters make the nanoparticles stable at physiological pH, but their hydrolysis in an acidic environment (pH = 5) leads to swelling/solubilization, therefore potentially allowing TA release in endosomal compartments...
October 13, 2016: Macromolecular Bioscience
Valentina Pirota, Simone Dell'Acqua, Enrico Monzani, Stefania Nicolis, Luigi Casella
The oxidative reactivity of copper complexes with Aβ peptides 1-16 and 1-28 (Aβ16 and Aβ28) against dopamine and related catechols under physiological conditions has been investigated in parallel with the competitive oxidative modification undergone by the peptides. It was found that both Aβ16 and Aβ28 markedly increase the oxidative reactivity of copper(II) towards the catechol compounds, up to a molar ratio of about 4:1 of peptide/copper(II). Copper redox cycling during the catalytic activity induces the competitive modification of the peptide at selected amino acid residues...
October 13, 2016: Chemistry: a European Journal
Grazia Chiellini, Giulia Nesi, Simona Sestito, Sara Chiarugi, Massimiliano Runfola, Stefano Espinoza, Martina Sabatini, Lorenza Bellusci, Annunziatina Laurino, Elena Cichero, Raul R Gainetdinov, Paola Fossa, Laura Raimondi, Riccardo Zucchi, Simona Rapposelli
The trace amine-associated receptor 1 (TAAR1) is a G-protein-coupled receptors (GPCR) potently activated by a variety of molecules besides trace amines (TAs), including thyroid hormone-derivatives like 3-iodothyronamine (T1AM), catechol-O-methyltransferase products like 3-methoxytyramine, and amphetamine-related compounds. Accordingly, TAAR1 is considered a promising target for medicinal development. To gain more insights into TAAR1 physiological functions and validation of its therapeutic potential we recently developed a new class of thyronamine-like derivatives...
October 12, 2016: Journal of Medicinal Chemistry
Kyeounghak Kim, Jeong Woo Han
Caffeic acid (CA) is well known for its strong adsorption on metal or metal oxide surfaces mostly due to the catecholic functional group. On the other hand, the detailed adsorption configurations and the effects of functional groups on molecular adsorption have not been clarified yet. In this study, first-principles calculations were implemented to elucidate the adsorption phenomena of CA and its deprotonated forms on Au(100), (110) and (111), and then predict the morphology of Au nanoparticles (AuNPs). The adsorption energetics and configurations were carefully examined by employing van der Waals interactions to take dispersion forces into consideration...
October 12, 2016: Physical Chemistry Chemical Physics: PCCP
Susan W Wesmiller, Susan M Sereika, Catherine M Bender, Dana Bovbjerg, Gretchen Ahrendt, Marguerite Bonaventura, Yvette P Conley
BACKGROUND: Postoperative nausea and vomiting (PONV) are two of the most frequent and distressing complications following surgical procedures, with as many as 80% of patients considered to be at risk. Despite recognition of well-established risk factors and the subsequent use of clinical guidelines, 20-30% of women do not respond to antiemetic protocols, indicating that there may be a genetic risk. OBJECTIVE: The purpose of this pilot study was to describe the incidence and explore the risk factors associated with PONV after surgery in women diagnosed with early stage breast cancer...
September 28, 2016: Autonomic Neuroscience: Basic & Clinical
Giacomo Cioncoloni, Hans M Senn, Stephen Sproules, Claire Wilson, Mark D Symes
Complexes of Co(iii) containing mixed chelating diimine and o-quinone ligand sets are of fundamental interest on account of their fascinating magnetic and electronic properties. Whilst complexes of this type containing one diimine and two o-quinone ligands have been studied extensively, those with the reverse stoichiometry (two diimines and one o-quinone) are much rarer. Herein, we describe a ready route to the synthesis of the complex [Co(III)(o-catecholate) (2,2'-bipyridine)2](+) (1), and also report the synthesis of [Co(III)(o-catecholate)(5,5'-dimethyl-2,2'-bipyridine)2](+) (2) and [Co(III)(o-benezenedithiolate)(5,5'-dimethyl-2,2'-bipyridine)2](+) (3) for the first time...
October 4, 2016: Dalton Transactions: An International Journal of Inorganic Chemistry
Yang J Xu, Kongchang Wei, Pengchao Zhao, Qian Feng, Chun Kit K Choi, Liming Bian
Mussel adhesion has inspired the development of catechol-based adhesive polymers. However, conventional strategies require basic pH conditions and lead to the loss of adhesion. To solve the problem, we report the first attempt to use thiourea-functionalized polymers for preserving hydrogel adhesion. We believe that this simple thiourea-quinone coupling chemistry is instrumental to synthetic adhesive materials.
October 10, 2016: Biomaterials Science
José A F de Oliveira, Marcos P da Silva, Bernardo de Souza, Tiago P Camargo, Bruno Szpoganicz, Ademir Neves, Adailton J Bortoluzzi
We describe herein the catecholase-like catalytic activity and dopamine polymerization by using a dinuclear [LCu(II)(μ-OH)2Cu(II)](ClO4)2 (1) complex where L is the dinucleating triazine-based ligand 6-chloro-N(2),N(2),N(4),N(4)-tetrakis(pyridin-2-ylmethyl)-1,3,5-triazine-2,4-diamine. The kinetic parameters (kcat = 0.318 s(-1), KM = 1.6 × 10(-3) mol L(-1), and kcat/KM = 198.8 L s(-1) mol(-1)), mechanistic insights into the oxidation of 3,5-di-tert-butyl catechol and early characterization of poly(dopamine) are presented...
October 4, 2016: Dalton Transactions: An International Journal of Inorganic Chemistry
Umamaheswari B, Rama Rajaram
Microaerobic degradation of 2-Mercaptobenzothiazole (2-MBT) was investigated using an isolated bacterial strain CSMB1. It was identified as Alcaligenes sp. MH146 by genomic analysis. The isolate degraded 50mg/L concentration of 2-MBT which was measured in terms of Total organic carbon (TOC) (700mg/L). A maximum degradation of 86% with a residual TOC concentration of 101mg/L was obtained after 72h, with the biomass growth of 290mg/L. The presence of specific activity of catechol 2, 3 oxygenase was observed in all the tested derivatives of benzothiazoles and the benzene ring opening was observed through meta cleavage...
October 3, 2016: Journal of Hazardous Materials
M Siddiq, K D Dolan
Polyphenol oxidase (PPO) was extracted and characterized from high-bush blueberries. PPO showed an optimum activity at pH 6.1-6.3 and 35°C, with the enzyme showing significant activity over a wide temperature range (25-60°C). Catechol was the most readily oxidized substrate followed by 4-methylcatechol, DL-DOPA, and dopamine. Blueberry PPO showed a Km of 15mM and Vmax of 2.57 ΔA420nm/min×10(-1), determined with catechol. PPO was completely inactivated in 20min at 85°C, however, after 30minat 75°C it showed about 10% residual activity...
March 1, 2017: Food Chemistry
Ana Amić, Bono Lučić, Višnja Stepanić, Zoran Marković, Svetlana Marković, Jasmina M Dimitrić Marković, Dragan Amić
Reaction energetics of the double (2H(+)/2e(-)), i.e., the first 1H(+)/1e(-) (catechol→ phenoxyl radical) and the second 1H(+)/1e(-) (phenoxyl radical→ quinone) free radical scavenging mechanisms of quercetin and its six colonic catecholic metabolites (caffeic acid, hydrocaffeic acid, homoprotocatechuic acid, protocatechuic acid, 4-methylcatechol, and catechol) were computationally studied using density functional theory, with the aim to estimate the antiradical potency of these molecules. We found that second hydrogen atom transfer (HAT) and second sequential proton loss electron transfer (SPLET) mechanisms are less energy demanding than the first ones indicating 2H(+)/2e(-) processes as inherent to catechol moiety...
March 1, 2017: Food Chemistry
Jisoo Shin, Jung Ho Cho, Yoonhee Jin, Kisuk Yang, Jong Seung Lee, Hyun-Ji Park, Hyung-Seop Han, Jinkyu Lee, Hojeong Jeon, Heungsoo Shin, Seung-Woo Cho
Using small interfering RNA (siRNA) to regulate gene expression is an emerging strategy for stem cell manipulation to improve stem cell therapy. However, conventional methods of siRNA delivery into stem cells based on solution-mediated transfection are limited due to low transfection efficiency and insufficient duration of cell-siRNA contact during lengthy culturing protocols. To overcome these limitations, a bio-inspired polymer-mediated reverse transfection system is developed consisting of implantable poly(lactic-co-glycolic acid) (PLGA) scaffolds functionalized with siRNA-lipidoid nanoparticle (sLNP) complexes via polydopamine (pDA) coating...
September 26, 2016: Small
N Shimomura, Y Egawa, R Miki, T Fujihara, Y Ishimaru, T Seki
A xanthene derivative containing a borinate moiety emitted red fluorescence with a high quantum yield. The interaction between the borinate and a sugar molecule induced a fluorescence change based on the change in the HOMO-LUMO gap. The response was pH-resistant in a wide range. In addition, catechol quenched through photoinduced electron transfer. The red fluorescence and polyol binding ability of dyes will pave the way for new biological applications of chemical sensors.
October 5, 2016: Organic & Biomolecular Chemistry
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