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https://www.readbyqxmd.com/read/28938642/facile-total-synthesis-of-lysicamine-and-the-anticancer-activities-of-the-ru-ii-rh-iii-mn-ii-and-zn-ii-complexes-of-lysicamine
#1
Jiao-Lan Qin, Ting Meng, Zhen-Feng Chen, Xiao-Li Xie, Qi-Pin Qin, Xiao-Ju He, Ke-Bin Huang, Hong Liang
Lysicamine is a natural oxoaporphine alkaloid, which isolated from traditional Chinese medicine (TCM) herbs and has been shown to possess cytotoxicity to hepatocarcinoma cell lines. Reports on its antitumor activity are scarce because lysicamine occurs in plants at a low content. In this work, we demonstrate a facile concise total synthesis of lysicamine from simple raw materials under mild reaction conditions, and the preparation of the Ru(II), Rh(III), Mn(II) and Zn(II) complexes 1-4 of lysicamine (LY). All the compounds were fully characterized by elemental analysis, IR, ESI-MS, (1)H and (13)C NMR, as well as single-crystal X-ray diffraction analysis...
August 29, 2017: Oncotarget
https://www.readbyqxmd.com/read/28938534/targeting-of-the-mapk-and-akt-pathways-in-conjunctival-melanoma-shows-potential-synergy
#2
Jinfeng Cao, Renier C Heijkants, Aart G Jochemsen, Mehmet Dogrusöz, Mark J de Lange, Pieter A van der Velden, Sjoerd H van der Burg, Martine J Jager, Robert M Verdijk
PURPOSE: Conjunctival melanoma (CM) is a rare but lethal form of cancer. Similar to cutaneous melanoma, CM frequently carries activating mutations in BRAF and NRAS. We studied whether CM as well as conjunctival benign and premalignant melanocytic lesions express targets in the mitogen-activated protein kinase (MAPK) and AKT pathways, and whether specific inhibitors can suppress CM growth in vitro. METHODS: 131 conjunctival lesions obtained from 129 patients were collected...
August 29, 2017: Oncotarget
https://www.readbyqxmd.com/read/28938486/the-two-populations-of-kisspeptin-neurons-are-involved-in-the-ram-induced-lh-pulsatile-secretion-and-lh-surge-in-anestrous-ewes
#3
C Fabre-Nys, J Cognié, L Dufourny, M S Ghenim, S Martinet, O Lasserre, D Lomet, R P Millar, S Ohkura, Y Suetomi
Exposure to a ram during spring stimulates luteinizing hormone (LH) secretion and can induce ovulation in sexually quiescent ewes ("ram effect"). Kisspeptins (Kiss) present in the arcuate nucleus (ARC) and the preoptic area (POA) are potent stimulators of LH secretion. Our aim was to investigate if Kiss neurons mediate the increase in LH secretion during the "ram effect". With double immunofluorescent detection we identified Kiss neurons (Kiss IR) activated (Fos IR) by exposure to a ram for 2h (M2), 12h (M12) or to ewes for 2h (C)...
September 1, 2017: Endocrinology
https://www.readbyqxmd.com/read/28937872/protective-effect-of-combined-caffeic-acid-phenethyl-ester-and-bevacizumab-against-hydrogen-peroxide-induced-oxidative-stress-in-human-rpe-cells
#4
Erdem Dinc, Lokman Ayaz, Akif Hakan Kurt
PURPOSE: This study aimed to evaluate the protective effects of caffeic acid phenethyl ester (CAPE) and combined CAPE-bevacizumab against oxidative stress induced by hydrogen peroxide (H2O2) in human retinal pigment epithelium. METHODS: ARPE-19 cells were pretreated with 5, 10, and 30 μM CAPE alone and in combination with bevacizumab for 3 h, then exposed to H2O2 for 16 h. Cell viability was evaluated with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay...
September 22, 2017: Current Eye Research
https://www.readbyqxmd.com/read/28937804/obesity-and-endometrial-cancer-a-lack-of-knowledge-but-opportunity-for-intervention
#5
Ashley F Haggerty, David B Sarwer, Kathryn H Schmitz, Emily M Ko, Kelly C Allison, Christina S Chu
OBJECTIVE: The causal link between obesity and endometrial cancer is well established; however obese women's knowledge of this relationship is unknown. Our objective was to explore patients' understanding of this relationship and assess the acceptability of a technology-based weight loss intervention. METHODS/MATERIALS: Obese women with Type I endometrial cancer/hyperplasia were surveyed about their assessment of their body mass, knowledge of the relationship of obesity and endometrial cancer, and eating and activity habits...
September 22, 2017: Nutrition and Cancer
https://www.readbyqxmd.com/read/28937756/direct-comparison-of-c-h-bond-amination-efficacy-through-manipulation-of-nitrogen-valence-centered-redox-imido-versus-iminyl
#6
Matthew J T Wilding, Diana A Iovan, Alexandra T Wrobel, James T Lukens, Samantha N MacMillan, Kyle M Lancaster, Theodore A Betley
Reduction of previously reported iminyl radical (ArL)FeCl(•N(C6H4-p-tBu)) (2) with potassium graphite furnished the corresponding high-spin (S = 5/2) imido (ArL)Fe(N(C6H4-p-tBu)) (3) (ArL = 5-mesityl-1,9-(2,4,6-Ph3C6H2)dipyrrin). Oxidation of the three-coordinate imido (ArL)Fe(NAd) (5) with chlorotriphenylmethane afforded (ArL)FeCl(•NAd) (6) with concomitant expulsion of Ph3C(C6H5)CPh2. The respective alkyl/aryl imido/iminyl pairs (3, 2; 5, 6) have been characterized by EPR, zero-field 57Fe Mössbauer, magnetometry, single crystal X-ray diffraction, XAS, and EXAFS for 6...
September 22, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28937749/heterooctamolybdate-based-clusters-h3-cp-rh-4pmo8o32-and-h5-na2-cp-ir-4pmo8o34-and-derived-hybrid-nanomaterials-with-efficient-electrocatalytic-hydrogen-evolution-reaction-activity
#7
Vikram Singh, Pengtao Ma, Michael G B Drew, Jingyang Niu, Jingping Wang, Guo-Xin Jin
Polyoxometalates (POMs), emerging as a new class of porous molecular materials, play a promising role in homo- and heterogeneous catalysis. Among them, noble-metal-decorated POMs have a profound impact as catalytic materials. Thus, it is imperative to design and structurally explore new catalysts including noble metals. Herein, two new clusters, H3[(Cp*Rh)4PMo8O32]·14H2O (1) and H5[Na2(Cp*Ir)4PMo8O34]·13H2O (2) (Cp* = pentamethylcyclopentadienyl), based on a heterooctamolybdate anionic core were successfully obtained via a one-pot reaction using [Cp*MCl2]2 [M = Rh (1) and Ir (2)] and Na2MoO4 in acidic conditions...
September 22, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28937744/methane-c-h-activation-via-3d-metal-methoxide-complexes-with-potentially-redox-noninnocent-pincer-ligands-a-density-functional-theory-study
#8
Ahmad Najafian, Thomas R Cundari
This paper reports a density functional theory study of 3d transition-metal methoxide complexes with potentially redox-noninnocent pincer supporting ligands for methane C-H bond activation to form methanol (LnM-OMe + CH4 → LnM-Me + CH3OH). The three types of tridentate pincer ligands [terpyridine (NNN), bis(2-pyridyl)phenyl-C,N,N' (NCN), and 2,6-bis(2-phenyl)pyridine-N,C,C' (CNC)] and different first-row transition metals (M = Ti, V, Cr, Mn, Fe, Co, Ni, and Cu) are used to elucidate the reaction mechanism as well as the effect of the metal identity on the thermodynamics and kinetics of a methane activation reaction...
September 22, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28937640/solvent-free-synthesis-and-safener-activity-of-sulfonylurea-benzothiazolines
#9
Ying Fu, Jing-Yi Wang, Dong Zhang, Yu-Feng Chen, Shuang Gao, Li-Xia Zhao, Fei Ye
A series of novel sulfonylurea benzothiazolines was designed by splicing active groups and bioisosterism. A solvent-free synthetic route was developed for the sulfonylurea benzothiazoline derivatives via the cyclization and carbamylation. All compounds were characterized by IR, ¹H-NMR, (13)C-NMR, HRMS. The biological activity tests indicated the compounds could protect maize against the injury caused by chlorsulfuron to some extent. The molecular docking result showed that the new compound competed with chlorsulfuron to bind with the herbicide target enzyme active site to attain detoxification...
September 22, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28937631/cellular-entry-of-the-diphtheria-toxin-does-not-require-the-formation-of-the-open-channel-state-by-its-translocation-domain
#10
Alexey S Ladokhin, Mauricio Vargas-Uribe, Mykola V Rodnin, Chiranjib Ghatak, Onkar Sharma
Cellular entry of diphtheria toxin is a multistage process involving receptor targeting, endocytosis, and translocation of the catalytic domain across the endosomal membrane into the cytosol. The latter is ensured by the translocation (T) domain of the toxin, capable of undergoing conformational refolding and membrane insertion in response to the acidification of the endosomal environment. While numerous now classical studies have demonstrated the formation of an ion-conducting conformation-the Open-Channel State (OCS)-as the final step of the refolding pathway, it remains unclear whether this channel constitutes an in vivo translocation pathway or is a byproduct of the translocation...
September 22, 2017: Toxins
https://www.readbyqxmd.com/read/28937578/trajectories-of-pain-severity-in-juvenile-idiopathic-arthritis-results-from-the-research-in-arthritis-in-canadian-children-emphasizing-outcomes-cohort
#11
N J Shiff, S Tupper, K Oen, J Guzman, H Lim, C H Lee, R Bryce, A M Huber, G Boire, P Dancey, B Feldman, R Laxer, P Miettunen, H Schmeling, K Watanabe Duffy, D M Levy, S Turvey, R Bolaria, A Bruns, D A Cabral, S Campillo, G Chedeville, D Ehrmann Feldman, E Haddad, K Houghton, N Johnson, R Jurencak, B Lang, M Larche, K Morishita, S Ramsey, J Roth, R Schneider, R Scuccimarri, L Spiegel, E Stringer, S M Tse, R Yeung, C M Duffy, L B Tucker
We studied children enrolled within 90 days of juvenile idiopathic arthritis (JIA) diagnosis in the Research in Arthritis in Canadian Children Emphasizing Outcomes (ReACCh-Out) prospective inception cohort to identify longitudinal trajectories of pain severity and features that may predict pain trajectory at diagnosis. A total of 1062 participants were followed a median of 24.3 months (IQR = 16.0, 37.1 months). Latent trajectory analysis of pain severity, measured in a 100mm visual analogue scale, identified 5 distinct trajectories: (A) mild-decreasing pain (56...
September 18, 2017: Pain
https://www.readbyqxmd.com/read/28937249/vagotomy-decreases-the-neuronal-activities-of-medulla-oblongata-and-alleviates-neurogenic-inflammation-of-airways-induced-by-repeated-intra-esophageal-instillation-of-hcl-in-guinea-pigs
#12
Z Chen, H Chen, F Chen, D Gu, L Sun, W Zhang, L Fan, Y Lin, R Dong, K Lai
Neuronal activity in the medulla oblongata and neurogenic inflammation of airways were investigated in a guinea pig model induced by repeated intra-esophageal instillation of hydrochloric acid (HCl) after vagotomy. Unilateral vagotomy was performed in the vagotomy group, while a sham-operation was performed in the sham group. Operation was not conducted in sham control group. Airway inflammation was observed with hematoxylin and eosin (HE) staining. C-fos protein was measured by immunohistochemistry (IHC) and Western blot (WB)...
September 22, 2017: Physiological Research
https://www.readbyqxmd.com/read/28937220/a-fluorescence-polarization-activity-based-protein-profiling-assay-in-the-discovery-of-potent-selective-inhibitors-for-human-non-lysosomal-glucosylceramidase
#13
Daniel Lahav, Bing Liu, Richard J B H N van den Berg, Adrianus M C H van den Nieuwendijk, Tom Wennekes, Amar T Ghisaidoobe, Imogen Breen, Maria J Ferraz, Chi-Lin Kuo, Liang Wu, Paul P Geurink, Huib Ovaa, Gijsbert A van der Marel, Mario van der Stelt, Rolf G Boot, Gideon J Davies, Johannes M F G Aerts, Herman S Overkleeft
Human non-lysosomal glucosylceramidase (GBA2) is one of several enzymes that controls levels of glycolipids and whose activity is linked to several human disease states. There is a major need to design or discover selective GBA2 inhibitors both as chemical tools and as potential therapeutic agents. Here, we describe the development of a fluorescence polarization activity-based protein profiling (FluoPol-ABPP) assay for the rapid identification, from a 350+ library of iminosugars, of GBA2 inhibitors. A focused library is generated based on leads from the FluoPol-ABPP screen and assessed on GBA2 selectivity offset against the other glucosylceramide metabolizing enzymes, glucosylceramide synthase (GCS), lysosomal glucosylceramidase (GBA) and the cytosolic retaining β-glucosidase, GBA3...
September 22, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28936681/production-of-r-mandelic-acid-using-nitrilase-from-recombinant-e-coli-cells-immobilized-with-tris-hydroxymethyl-phosphine
#14
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/28936604/production-partial-optimization-and-characterization-of-keratinase-enzyme-by-arthrobacter-sp-nfh5-isolated-from-soil-samples
#15
Nirmal Chandra Barman, Fatema Tuj Zohora, Keshob Chandra Das, Md Golam Mowla, Nilufa Akhter Banu, Md Salimullah, Abu Hashem
The study was conducted to select the best promising keratinolytic bacterial strain. A good keratinase positive bacterium isolated from the soil samples of Hazaribagh tannery industrial zone, Dhaka was identified as Arthrobacter genus depending on the conventional techniques and confirmed as Arthrobacter sp. by sequencing 16S rRNA gene. The medium components and culture conditions were optimized to enhance keratinase production through shake flask culture. Keratin and feather powder (10 g/l or 1%) were good substrates for the highest keratinase production along with yeast extract (0...
September 21, 2017: AMB Express
https://www.readbyqxmd.com/read/28936521/a-first-principles-study-of-spinel-znfe2o4-for-electrode-materials-in-lithium-ion-batteries
#16
Haoyue Guo, Yiman Zhang, Amy C Marschilok, Kenneth J Takeuchi, Esther S Takeuchi, Ping Liu
Zinc ferrite (ZnFe2O4) is a prospective lithium ion battery (LIB) material, owing to its large theoretical capacity (1000 mA h g(-1)). Here, we report a density functional study of the discharge process at an early stage from ZnFe2O4 up to LixZnFe2O4 (x = 2), aiming to provide a fundamental understanding of the mechanism. According to our calculations, with x increasing up to 1 the intercalation of Li(+) ions prefers octahedral 16c sites, which is accompanied by Zn(2+) ion displacement from tetrahedral 8a sites to 16c sites starting at x = 0...
September 22, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28936334/synthesis-of-bioactive-and-stabilized-cyclic-peptides-by-macrocyclization-using-c-sp-3-h-activation
#17
Jian Tang, Yadong He, Hongfei Chen, Wangjian Sheng, Huan Wang
Cyclic peptides have attracted increasing attention in recent years due to their ability to inhibit protein-protein interactions. Current strategies to prepare cyclic peptides often rely on functional amino acid side chains or the incorporation of unnatural amino acids, thus limiting their structural diversity. Here, we describe the development of a highly versatile peptide macrocyclization strategy through a palladium-catalyzed C(sp(3))-H activation and the synthesis of cyclic peptides featuring unique hydrocarbon linkages between the β-carbon of amino acids and the aromatic side chains of Phe and Trp...
June 1, 2017: Chemical Science
https://www.readbyqxmd.com/read/28936331/double-c-h-bond-activation-of-acetylene-by-atomic-boron-in-forming-aromatic-cyclic-hbc2bh-in-solid-neon
#18
Jiwen Jian, Wei Li, Xuan Wu, Mingfei Zhou
The organo-boron species formed from the reactions of boron atoms with acetylene in solid neon are investigated using matrix isolation infrared spectroscopy with isotopic substitutions as well as quantum chemical calculations. Besides the previously reported single C-H bond activation species, a cyclic-HBC2BH diboron species is formed via double C-H bond activation of acetylene. It is characterized to have a closed-shell singlet ground state with planar D2h symmetry. Bonding analysis indicates that it is a doubly aromatic species involving two delocalized σ electrons and two delocalized π electrons...
June 1, 2017: Chemical Science
https://www.readbyqxmd.com/read/28935974/membrane-particles-generated-from-mesenchymal-stromal-cells-modulate-immune-responses-by-selective-targeting-of-pro-inflammatory-monocytes
#19
Fabiany da C Gonçalves, Franka Luk, Sander S Korevaar, Rachid Bouzid, Ana H Paz, Carmen López-Iglesias, Carla C Baan, Ana Merino, Martin J Hoogduijn
Mesenchymal stromal cells (MSC) are a promising therapy for immunological disorders. However, culture expanded MSC are large and get trapped in the capillary networks of the lungs after intravenous infusion, where they have a short survival time. Hypothetically, living cells are a risk for tumor formation. To reduce risks associated with MSC infusion and improve the distribution in the body, we generated membrane particles (MP) of MSC and MSC stimulated with IFN-γ (MPγ). Tracking analysis and electron microscopy indicated that the average size of MP was 120 nm, and they showed a round shape...
September 21, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28935960/combined-activation-of-map-kinase-pathway-and-%C3%AE-catenin-signaling-cause-deep-penetrating-nevi
#20
Iwei Yeh, Ursula E Lang, Emeline Durieux, Meng Kian Tee, Aparna Jorapur, A Hunter Shain, Veronique Haddad, Daniel Pissaloux, Xu Chen, Lorenzo Cerroni, Robert L Judson, Philip E LeBoit, Timothy H McCalmont, Boris C Bastian, Arnaud de la Fouchardière
Deep penetrating nevus (DPN) is characterized by enlarged, pigmented melanocytes that extend through the dermis. DPN can be difficult to distinguish from melanoma but rarely displays aggressive biological behavior. Here, we identify a combination of mutations of the β-catenin and mitogen-activated protein kinase pathways as characteristic of DPN. Mutations of the β-catenin pathway change the phenotype of a common nevus with BRAF mutation into that of DPN, with increased pigmentation, cell volume and nuclear cyclin D1 levels...
September 21, 2017: Nature Communications
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