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https://www.readbyqxmd.com/read/28811868/selaginella-bryopteris-aqueous-extract-improves-stability-and-function-of-cryopreserved-human-mesenchymal-stem-cells
#1
Abhishek Kumar Singh, Anubhuti Jha, Arindam Bit, Andrey P Kiassov, Albert A Rizvanov, Archit Ojha, Pooja Bhoi, Pradeep Kumar Patra, Awanish Kumar, Akalabya Bissoyi
The effective long-term cryopreservation of human mesenchymal stem cells (MSCs) is an essential prerequisite step and represents a critical approach for their sustained supply in basic research, regenerative medicine, and tissue engineering applications. Therefore, attempts have been made in the present investigation to formulate a freezing solution consisting of a combination of Selaginella bryopteris water-soluble extract with and without dimethyl sulfoxide (Me2SO) for the efficient long-term storage of human umbilical cord blood- (hUCB-) derived MSCs...
2017: Oxidative Medicine and Cellular Longevity
https://www.readbyqxmd.com/read/28811248/development-of-an-elisa-for-the-diagnosis-of-reactive-ige-antibodies-anti-therapeutic-horse-sera
#2
Salvatore Giovanni De-Simone, Andre Luis Almeida Souza, Aniesse Silva Aguiar, Anibal Raphel Melgarejo, David William Provance-Jr
Hypersensitive diseases that involve IgE reactivity are important concern of public, especially those encompassing the potential pathogenesis from the administration of horse serum-based therapeutics such as antivenoms. A method for the definitive diagnosis of reactive IgE is important for identifying allergic patients to control severe collateral effects during planned and emergency application of immunotherapies when the allergy source cannot be avoided for treatment. To date, no tests have been developed to accompany the wide range of antivenoms produced from horse sera...
August 12, 2017: Toxicon: Official Journal of the International Society on Toxinology
https://www.readbyqxmd.com/read/28809113/theoretical-investigation-of-methane-hydroxylation-over-isoelectronic-feo-2-and-mno-exchanged-zeolites-activated-by-n2o
#3
M Haris Mahyuddin, Yoshihito Shiota, Aleksandar Staykov, Kazunari Yoshizawa
While the most likely structure of the active site in iron-containing zeolites has been recently identified as [FeO](2+) (Snyder et al. Nature 2016, 536, 317-321), the mechanism for the direct conversion of methane to methanol over this active species is still debatable between the direct-radical-rebound or nonradical (concerted) mechanism. Using density functional theory on periodic systems, we calculated the two reaction mechanisms over two d(4) isoelectronic systems, [FeO](2+) and [MnO](+) zeolites. We found that [FeO](2+) zeolites favor the direct-radical-rebound mechanism with low CH4 activation energies, while [MnO](+) zeolites prefer the nonradical mechanism with higher CH4 activation energies...
August 15, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28800015/the-utility-of-nkx2-2-and-tle1-immunohistochemistry-in-the-differentiation-of-ewing-sarcoma-and-synovial-sarcoma
#4
Lisa M Rooper, Rajni Sharma, Christopher D Gocke, Deborah A Belchis
Although molecular testing can definitively distinguish Ewing sarcoma (EWS) from synovial sarcoma (SS) it is frequently desirable to provide a confident preliminary diagnosis before such analysis can be completed. Recently, the nuclear markers NKX2.2 and TLE1 have been shown to have good sensitivity but imperfect specificity, respectively, for EWS and SS. However, the performance of these markers has not been extensively evaluated within this specific differential diagnosis. This study performed NKX2.2, TLE1, and CD99 immunohistochemistry in a group of EWS and SSs confirmed by reverse transcription-polymerase chain reaction to evaluate the utility of these novel markers in this context...
August 9, 2017: Applied Immunohistochemistry & Molecular Morphology: AIMM
https://www.readbyqxmd.com/read/28799055/risk-factors-for-complicated-diverticulitis-systematic-review-and-meta-analysis
#5
REVIEW
H E Bolkenstein, B J M van de Wall, E C J Consten, I A M J Broeders, W A Draaisma
PURPOSE: The aim of this systematic review is to identify risk factors that can predict complicated diverticulitis. Uncomplicated diverticulitis is a self-limiting and mild disease, but 10% of patients with diverticulitis develop complications requiring further treatment. It is important to estimate the risk of developing complicated diverticulitis at an early stage to set the right treatment at initial presentation. METHODS: Embase, MEDLINE, and Cochrane databases were searched for studies reporting on risk factors for complicated diverticulitis...
August 10, 2017: International Journal of Colorectal Disease
https://www.readbyqxmd.com/read/28797840/nerves-h2o2-and-shh-three-players-in-the-game-of-regeneration
#6
REVIEW
Francesca Meda, Christine Rampon, Edmond Dupont, Carole Gauron, Aurélien Mourton, Isabelle Queguiner, Marion Thauvin, Michel Volovitch, Alain Joliot, Sophie Vriz
The tight control of reactive oxygen species (ROS) levels is required during regeneration. H2O2 in particular assumes clear signalling functions at different steps in this process. Injured nerves induce high levels of H2O2 through the activation of the Hedgehog (Shh) pathway, providing an environment that promotes cell plasticity, progenitor recruitment and blastema formation. In turn, high H2O2 levels contribute to growing axon attraction. Once re-innervation is completed, nerves subsequently downregulate H2O2 levels to their original state...
August 7, 2017: Seminars in Cell & Developmental Biology
https://www.readbyqxmd.com/read/28796492/structural-and-morphological-description-of-sn-snox-core-shell-nanoparticles-synthesized-and-isolated-from-ionic-liquid
#7
Nadia Soulmi, Damien Dambournet, Cécile Rizzi, Juliette Sirieix-Plénet, Mathieu Duttine, Alain Wattiaux, Jolanta Swiatowska, Olaf J Borkiewicz, Henri Groult, Laurent Gaillon
The potential application of high capacity Sn-based electrode materials for energy storage, particularly in rechargeable batteries, has led to extensive research activities. In this scope, the development of an innovative synthesis route allowing to downsize particles to the nanoscale is of particular interest owing to the ability of such nanomaterial to better accommodate volume changes upon electrochemical reactions. Here, we report on the use of room temperature ionic liquid (i.e., [EMIm(+)][TFSI(-)]) as solvent, template, and stabilizer for Sn-based nanoparticles...
August 10, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28796395/indole-and-pyrrole-bx-bench-stable-hypervalent-iodine-reagents-for-heterocycle-umpolung
#8
Paola Caramenti, Stefano Nicolai, Jerome Waser
The one-step synthesis of the bench-stable hypervalent iodine reagents IndoleBX and PyrroleBX using mild Lewis acid catalyzed conditions is reported. The new reagents are stable up to 150 °C and were applied in the C-H arylation of unactivated arenes using either rhodium or ruthenium catalysts. A broad range of heterocyclic systems of high interest for synthetic and medicinal chemistry was accessed in high yields. The developed C-H functionalization could not be achieved using reported reagents or methods, highlighting the unique reactivity of Indole- and Pyrrole-BX...
August 10, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/28795960/advances-in-experimental-optic-nerve-regeneration
#9
Bo Young Chun, Dean M Cestari
PURPOSE OF REVIEW: Recent advances in experimental studies of optic nerve regeneration to better understand the pathophysiology of axon regrowth and provide insights into the future treatment of numerous optic neuropathies. RECENT FINDINGS: The optic nerve is part of the central nervous system and cannot regenerate if injured. There are several steps that regenerating axons of retinal ganglion cells (RGCs) must take following optic nerve injury that include: maximizing the intrinsic growth capacity of RGCs, overcoming the extrinsic growth-inhibitory environment of the optic nerve, and optimizing the reinnervation of regenerated axons to their targets in the brain...
August 8, 2017: Current Opinion in Ophthalmology
https://www.readbyqxmd.com/read/28792915/fast-rbc-loading-by-fluorescent-antibodies-and-nuclei-staining-dye-and-their-potential-bioanalytical-applications
#10
Mohamed K Al-Essa, Susanne Melzer, Attila Tarnok, Kamal A Hadidi, Mohammed El-Khateeb
This study was designed to load different antibodies (Abs) and a fluorescent dye onto the red blood cell (RBC) surface. We have used fluorescein isothiocyanate (FITC)-conjugate anti-human Ab, CD22-PE (B-cell marker-phycoerythrin Ab), and 4',6-diamidino-2-phenylindole (DAPI) for insertion over the RBC surface. In a first step, conjugation experiments were performed: in dimethyl sulfoxide (DMSO), RBCs were conserved and modified by succinic anhydride to create an additional -COOH group, and then activated with 3-(3-dimethylaminopropyl)carbodiimide-N-hydroxysuccinimide (EDC-NHS) in 2-(N-morpholino) ethanesulfonic acid hydrate buffer for insertion of labeled Abs or DAPI...
August 9, 2017: Zeitschrift Für Naturforschung. C, A Journal of Biosciences
https://www.readbyqxmd.com/read/28792609/egcg-attenuates-fe-iii-induced-conformational-transition-of-%C3%AE-synuclein-and-protects-as-pc12-cells-against-fe-iii-induced-death
#11
Juan Zhao, Lihui Xu, Qingnan Liang, Qing Sun, Congheng Chen, Yuan Zhang, Yu Ding, Ping Zhou
The fibrillation and aggregation of α-synuclein (AS), along with the conformational transition from random coil to β-sheet, are the critical steps in the development of Parkinson's disease (PD). It is acknowledged that iron accumulation in the brain may lead to the fibrillation of AS. However, (-)-epigallocatechin gallate (EGCG) can penetrate the blood-brain barrier, chelate metal ions and inhibit the fibrillation of amyloid proteins. Therefore, EGCG is warranted to be investigated for its potential to cure amyloid-related diseases...
August 9, 2017: Journal of Neurochemistry
https://www.readbyqxmd.com/read/28791745/a-novel-pathway-of-protein-haptenation-by-%C3%A3-lactams
#12
M Consuelo Jiménez, Raúl Pérez-Ruiz, Emilio Lence, Inmaculada Andreu, Concepción González-Bello, Miguel A Miranda, Daniel Limones-Herrero
The covalent binding of β-lactams to proteins upon photochemical activation has been demonstrated using an integrated approach that combines photochemical, proteomic and computational studies, selecting human serum albumin (HSA) as target protein and ezetimibe (1) as probe. The results have revealed a novel protein haptenation pathway by this family of drugs that is alternative to the known nucleophilic ring opening of β-lactams by the free amino group of lysine residues. Thus, photochemical ring splitting of the β-lactam ring following a formal retro-Staudinger reaction gives a highly reactive ketene intermediate that is trapped by the neighboring lysine residues, leading to an amide adduct...
August 9, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/28791416/luteolin-induces-apoptotic-cell-death-via-antioxidant-activity-in-human-colon-cancer-cells
#13
Kyoung Ah Kang, Mei Jing Piao, Yea Seong Ryu, Yu Jae Hyun, Jeong Eon Park, Kristina Shilnikova, Ao Xuan Zhen, Hee Kyoung Kang, Young Sang Koh, Yong Joo Jeong, Jin Won Hyun
The present study determined whether luteolin induces HT-29 colon cancer cell death through an antioxidant effect such as the activation of antioxidant enzymes. Luteolin decreased cell viability in human colon cancer cells (HT-29), whereas it had no effect on normal colon cells (FHC). Luteolin induced apoptosis by activating the mitochondria-mediated caspase pathway in HT-29 cells. Luteolin caused loss of the mitochondrial membrane action potential, increased mitochondrial Ca2+ level, upregulated Bax, downregulated Bcl-2, induced the release of cytochrome c from mitochondria to the cytosol, and increased the levels of the active forms of caspase-9 and caspase-3...
August 2, 2017: International Journal of Oncology
https://www.readbyqxmd.com/read/28783336/optimization-of-enzyme-mechanism-along-the-evolutionary-trajectory-of-a-computationally-designed-retro-aldolase
#14
Cathleen Zeymer, Reinhard Zschoche, Donald Hilvert
De novo biocatalysts have been successfully generated by computational design and subsequent experimental optimization. Here, we examined the evolutionary history of the computationally designed (retro-)aldolase RA95. The modest activity of the starting enzyme was previously improved 10(5) fold over many rounds of mutagenesis and screening to afford a proficient biocatalyst for enantioselective cleavage and synthesis of β-hydroxyketones. Using a set of representative RA95 variants, we probed individual steps in the multistep reaction pathway to determine which processes limit steady-state turnover and how mutations that accumulated along the evolutionary trajectory influenced the kinetic mechanism...
August 7, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28783207/cyclopalladation-in-the-periphery-of-a-nhc-ligand-as-the-crucial-step-in-the-synthesis-of-highly-active-suzuki-miyaura-cross-coupling-catalysts
#15
Agnes Fizia, Maximilian Gaffga, Johannes Lang, Yu Sun, Gereon Niedner-Schatteburg, Werner R Thiel
Starting from 2,4-dichloropyrimidine, 4-(2-dialkylamino)pyrimidinyl functionalized mesitylimidazolium chlorides are accessible in a five-step reaction sequence. Two routes leading to palladium NHC complexes derived from these ligands have been worked out: By transmetallation with the corresponding NHC-AgCl complexes, C,N-coordinated palladium(II) complexes can be obtained. Treatment of palladium dichloride with the imidazolium salts in pyridine and in the presence of K2CO3 gives cyclometallated and thus C,C-coordinated compounds...
August 7, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/28779895/whole-cell-bioreporters-and-risk-assessment-of-environmental-pollution-a-proof-of-concept-study-using-lead
#16
Xiaokai Zhang, Boqiang Qin, Jianming Deng, Mona Wells
As the world burden of environmental contamination increases, it is of the utmost importance to develop streamlined approaches to environmental risk assessment in order to prioritize mitigation measures. Whole-cell biosensors or bioreporters and speciation modeling have both become of increasing interest to determine the bioavailability of pollutants, as bioavailability is increasingly in use as an indicator of risk. Herein, we examine whether bioreporter results are able to reflect expectations based on chemical reactivity and speciation modeling, with the hope to extend the research into a wider framework of risk assessment...
August 2, 2017: Environmental Pollution
https://www.readbyqxmd.com/read/28777573/excited-state-dynamics-of-cold-protonated-cytosine-tautomers-characterization-of-charge-transfer-inter-system-crossing-and-internal-conversion-processes
#17
Michel Broquier, Satchin Soorkia, Gustavo A Pino, Claude Dedonder-Lardeux, Christophe Jouvet, Gilles Gregoire
Charge transfer reactions are ubiquitous in chemical reactivity and often viewed as ultrafast processes. For DNA, femtochemistry has undeniably revealed the primary stage of the deactivation dynamics of the locally excited state following electronic excitation. We here demonstrate that the full time scale excited state dynamics can be followed up to milliseconds through an original pump-probe photodissociation scheme applied to cryogenic ion spectroscopy. Protonated cytosine is chosen as a benchmark system in which the locally excited (1)ππ* state decays in the femtosecond range towards long-lived charge transfer state and triplet state with lifetimes ranging from microseconds to milliseconds, respectively...
August 4, 2017: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/28777558/high-spin-iron-imido-complexes-competent-for-c-h-bond-amination
#18
Matthew J T Wilding, Diana A Iovan, Theodore A Betley
Reduction of previously reported (ArL)FeCl with potassium graphite furnished a low-spin (S = ½) iron complex (ArL)Fe which features an intramolecular η6-arene interaction and can be utilized as an FeI synthon (ArL = 5-mesityl-1,9-(2,4,6-Ph3C6H2)dipyrrin). Treatment of (ArL)Fe with adamantyl azide or mesityl azide led to the formation of the high-spin (S = 5/2), three-coordinate imidos (ArL)Fe(NAd) and (ArL)Fe(NMes), respectively, as determined by EPR, zero-field 57Fe Mössbauer, magnetometry, and single crystal X-ray diffraction...
August 4, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28773147/recent-developments-in-organophosphorus-flame-retardants-containing-p-c-bond-and-their-applications
#19
REVIEW
Sophie Wendels, Thiebault Chavez, Martin Bonnet, Khalifah A Salmeia, Sabyasachi Gaan
Organophosphorus compounds containing P-C bonds are increasingly developed as flame retardant additives due to their excellent thermal and hydrolytic stability and ease of synthesis. The latest development (since 2010) in organophosphorus flame retardants containing P-C bonds summarized in this review. In this review, we have broadly classified such phosphorus compounds based on the carbon unit linked to the phosphorus atom i.e., could be a part of either an aliphatic or an aromatic unit. We have only considered those published literature where a P-C bond was created as a part of synthetic strategy to make either an intermediate or a final organophosphorus compound with an aim to use it as a flame retardant...
July 11, 2017: Materials
https://www.readbyqxmd.com/read/28772515/pore-formation-process-of-porous-ti3sic2-fabricated-by-reactive-sintering
#20
Huibin Zhang, Xinli Liu, Yao Jiang
Porous Ti3SiC2 was fabricated with high purity, 99.4 vol %, through reactive sintering of titanium hydride (TiH2), silicon (Si) and graphite (C) elemental powders. The reaction procedures and the pore structure evolution during the sintering process were systematically studied by X-ray diffraction (XRD) and scanning electron microscope (SEM). Our results show that the formation of Ti3SiC2 from TiH2/Si/C powders experienced the following steps: firstly, TiH2 decomposed into Ti; secondly, TiC and Ti5Si3 intermediate phases were generated; finally, Ti3SiC2 was produced through the reaction of TiC, Ti5Si3 and Si...
February 10, 2017: Materials
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