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Strong ion difference

Attila Forgács, Rosa Pujales-Paradela, Martín Regueiro-Figueroa, Laura Valencia, David Esteban-Gómez, Mauro Botta, Carlos Platas-Iglesias
We have reported here a series of ligands containing pentadentate 6,6'-(azanediylbis(methylene))dipicolinic acid units that differ in the substituent present at the amine nitrogen atom (acetate: H3DPAAA; phenyl: H2DPAPhA; dodecyl: H2DPAC12A; 4-hexylphenyl: H2DPAC6PhA). The protonation constants of the hexadentate DPAAA(3-) and pentadentate DPAPhA(2-) ligands and the stability constants of their Mn(2+) complexes were determined using pH-potentiometry (25 °C, 0.15 M NaCl). The mono-hydrated [Mn(DPAAA)](-) complex (log KMnL = 13...
January 16, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
Daijiro Kobayashi, Takahiro Oike, Atsushi Shibata, Atsuko Niimi, Yoshiki Kubota, Makoto Sakai, Napapat Amornwhichet, Yuya Yoshimoto, Yoshihiko Hagiwara, Yuka Kimura, Yuka Hirota, Hiro Sato, Mayu Isono, Yukari Yoshida, Takashi Kohno, Tatsuya Ohno, Takashi Nakano
In cancer therapy today, carbon ion radiotherapy is used mainly as monotherapy, whereas cisplatin is used concomitantly with X-ray radiotherapy. The effectiveness of concomitant carbon ions and cisplatin is unclear. To obtain the information on the mechanisms potentially shared between carbon ions or X-rays and cisplatin, we assessed the correlation of sensitivity to the single treatments. In 20 human cancer cell lines, sensitivity to X-rays strongly correlated with sensitivity to cisplatin, indicating the presence of potentially shared target mechanisms...
January 16, 2017: Scientific Reports
T Jovaisa, V Vicka, G Linkaitė, J Guseinovaitė, D Ringaitienė, I Norkienė
There is a growing interest in the effects of plasma sodium levels on postoperative outcomes. A trend of using balanced crystalloid solutions is based on the extensive data on chloride and the strong ion difference-related acidosis. However, effects of sodium are often overlooked in this context. The aim of the study was to establish the effects of the routine use of Lactated Ringer’s Solution (RL) on postoperative changes in sodium concentrations and whether these changes result in metabolic acidosis. We performed database analysis of 358 consecutive elective on-pump cardiac surgery cases in a tertiary referral university hospital...
October 2016: Journal of Biological Regulators and Homeostatic Agents
Lipeng Hou, Weichang Zhou, Bingsuo Zou, Yu Zhang, Junbo Han, Xinxin Yang, Zhihong Gong, Jingbo Li, Sishen Xie, Lijie Shi
For their spintronic applications the magnetic and optical properties of diluted magnetic semiconductors (DMS) have been studied widely. However, the exact relationships between their magnetic interactions and optical emission behaviors in DMS are not well understood yet due to their complicated microstructural and compositional characters from different growth and preparation techniques. Manganese (Mn) doped ZnSe nanoribbons with high quality were obtained by using the chemical vapor deposition (CVD) method...
January 12, 2017: Nanotechnology
Taichi Hamanaka, Keiko Nishizawa, Yuji Sakasegawa, Ayumi Oguma, Kenta Teruya, Hiroshi Kurahashi, Hideyuki Hara, Suehiro Sakaguchi, Katsumi Doh-Ura
Prion diseases are progressive fatal neurodegenerative illnesses caused by the accumulation of transmissible abnormal prion protein (PrP). To find treatments for prion diseases, we searched for substances from natural resources that inhibit abnormal PrP formation in prion-infected cells. We found that high-molecular-weight components from insect cuticle extracts reduced abnormal PrP levels. The chemical nature of these components was consistent with that of melanin. In fact, synthetic melanin produced from tyrosine or 3-hydroxy-l-tyrosine inhibited abnormal PrP formation...
January 11, 2017: Journal of Virology
Paul Avramov, Alexander A Kuzubov, Artem V Kuklin, Hyosun Lee, Evgenia A Kovaleva, Seiji Sakai, Shiro Entani, Hiroshi Naramoto, Pavel B Sorokin
The structure of the interfaces and the mechanisms of induced spin polarization of 1D infinite and finite narrow graphene- and h-BN zigzag nanoribbons placed on a SrO-terminated La1-xSrxMnO3 (LSMO) (001) surface were studied using density functional theory (DFT) electronic structure calculations. It was found that the π-conjugated nanofragments are bonded to the LSMO(001) surface by weak disperse interactions. The types of coordination of the fragments, the strength of bonding, and the rate of spin polarization depend upon the nature of the fragments...
January 11, 2017: Journal of Physical Chemistry. A
Bogdan Dereka, Marius Koch, Eric Vauthey
Because of its crucial role in many areas of science and technology, photoinduced electron transfer is the most investigated photochemical reaction. Despite this, several important questions remain open. We present recent efforts to answer some of them, which concern both inter- and intramolecular processes. The decisive factor that allowed these issues to be successfully addressed was the use of time-resolved infrared (TRIR) spectroscopy. Many different transient species, such as tight and loose ion pairs (TIPs and LIPs) and exciplexes, have been invoked to explain the dynamics of intermolecular photoinduced charge separation reactions (i...
January 9, 2017: Accounts of Chemical Research
Patricio Ulloa-Rodríguez, Elías Figueroa, Rommy Díaz, Manuel Lee-Estevez, Stefania Short, Jorge G Farías
There is an extraordinary diversity of reproductive modes in teleost and this variability is related to the phylogenetic relationships and adaption to very different biotopes. As in all vertebrates, sperm is produced as the end product of the process of spermatogenesis, and regarding teleost the spermatozoa lack an acrosome in almost all species and motility is activated as a response to osmolarity and ion content of the aquatic medium where the sperm is released. In this context, mitochondria possess a fundamental role for fish spermatozoa motility and integrity, hence, fertilizing potential; they are the energy supplier that allows flagellar movement and their dysfunction could play a main role in structural and functional damage to the spermatozoa...
January 5, 2017: Mitochondrion
M Aminul Haque
Landfill solid waste management system poses the potential source of silent wide-spread heavy metals like nickel poisoning in the entire ecosystem of nearby environment. Nickel containing demolish solid wastes are disposed at landfill zones to a great extent from where nickel migrate into the food chain through the surface water body as well as groundwater. Consequently, nickel exposure may cause different environmental problems. From this sense, it may be an attractive proposal to recycle the waste as a sustainable product...
January 5, 2017: Journal of Environmental Management
Adele Romano, Gaetano Serviddio, Silvio Calcagnini, Rosanna Villani, Anna Maria Giudetti, Tommaso Cassano, Silvana Gaetani
4-hydroxy-2-nonenal (HNE) is considered to be a strong marker of oxidative stress; the interaction between HNE and cellular proteins leads to the formation of HNE-protein adducts able to alter cellular homeostasis and cause the development of a pathological state. By virtue of its high lipid concentration, oxygen utilization, and the presence of metal ions participating to redox reactions, the brain is highly susceptible to the formation of free radicals and HNE-related compounds. A variety of neuropsychiatric disorders have been associated with elevations of HNE concentration...
January 4, 2017: Free Radical Biology & Medicine
Jean-Pierre Kaiser, Matthias Roesslein, Liliane Diener, Adrian Wichser, Bernd Nowack, Peter Wick
BACKGROUND: Nanosilver shows great promise for use in industrial, consumer or medical products because of its antimicrobial properties. However, the underlying mechanisms of the effects of silver nanoparticles on human cells are still controversial. Therefore, in the present study the influence of the chloride concentration and different serum content of culture media on the cytotoxic effects of nanosilver was systematically evaluated. RESULTS: Our results show that nanosilver toxicity was strongly affected by the composition of the culture media...
January 6, 2017: Journal of Nanobiotechnology
Chaelin Kim, Ka Young Kim, Ji Ha Lee, Junho Ahn, Kazuo Sakurai, Shim Sung Lee, Jong Hwa Jung
We report the correlation between the luminescence intensity and the helical pitch of supramolecular hydrogels with Tb(III) and Eu(III) as well as their inkjet printing patterning as an application. The luminescent gels, which exhibited three different emissions of red, green, and blue, could be prepared without and with Eu(III) and Tb(III). The luminescence intensity of supramolecular gels (gel-Tb and gel-Eu) composed of Tb(III) and Eu(III) was ca. 3 fold larger than that of the sol (1+Tb(III) or 1+Eu(III)), which was attributed to large tilting angles between molecules...
January 6, 2017: ACS Applied Materials & Interfaces
Ryutaro Souda
Methanol is known as a strong inhibitor of hydrate formation, but clathrate hydrates of ethanol and 1-propanol can be formed in the presence of help gases. To elucidate the hydrophilic and hydrophobic effects of alcohols, their interactions with simple solute species are investigated in glassy, liquid, and crystalline water using temperature-programmed desorption and time-of-flight secondary ion mass spectrometry. Nonpolar solute species embedded underneath amorphous solid water films are released during crystallization, but they tend to withstand water crystallization under the coexistence of methanol additives...
January 6, 2017: Physical Chemistry Chemical Physics: PCCP
Afang Zhang, Jun Wang, Feng Shao, Wen Li, Jiatao Yan, Kun Liu, Pei Tao, Toshio Masuda
We present investigation on supramolecular assembly of C3-molecules benzene-1,3,5-tricarboxamides carrying tetrapeptide Gly-Ala-Gly-Ala pendants driving competitively by hydrogen bonding and metal ion coordination. Gly-Ala peptide sequence was selected as it is the most abundant repeating units in silkworm silk, and known to be able to form β-sheets through efficient intermolecular hydrogen bonds. These C3-peptides were found to form long helical fibers in solvents mainly due to strong hydrogen bonding. However, in the presence of divalent metal ions, chirality of these helical fibers was enhanced through metal coordination and can be transformed into nanospheres with excess amount of the ions...
January 5, 2017: Chemistry, An Asian Journal
Eli A Sutter, Peter W Sutter
Galvanic replacement reactions are important as they transform nanoparticle templates into complex porous and hollow metal or alloy nanostructures with interesting properties for a variety of applications. Real-time liquid cell electron microscopy (LCEM) observations of the transformation of solid nanoparticles into hollow shell and cage bimetallic nanostructures are challenging because the high-energy electron beam strongly affects the galvanic process via species such as aqueous electrons and hydroxyl radicals generated through the radiolysis of water in the liquid cell...
January 5, 2017: Nanoscale
Bence Kutus, Dániel Ozsvár, Norbert Varga, István Pálinkó, Pál Sipos
The complex formation equilibria between Ca(2+) ions and six carbohydrate derivatives related to d-glucose was quantitatively characterized by potentiometry, freezing point depression and polarimetry. Complexation could not be observed for d-glucose, while weak association was deduced for d-sorbitol and d-mannitol. Stronger complexes are formed with d-gluconate and d-heptagluconate due to the presence of the carboxylate group. In addition to the plausible 1 : 1 species, the 1 : 2 species can also be detected at higher ligand to metal ratios...
January 5, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
Rafael Nunes, Paulo Jorge Costa
The interaction of 2-halo-functionalized imidazolium derivatives (n-X+, X = Cl, Br, I) with chloride anion via ion-pair halogen bonds (n-X∙Cl) was studied by means of DFT and ab initio calculations. A method benchmark was performed on 2-bromo-1H-imidazol-3-ium in association with chloride (1-Br∙Cl), MP2 yielding the best results when compared with CCSD(T) calculations. The interaction energies in the gas-phase are high and, although the electrostatic interaction is strong owing to the ion-pair nature of the system, large X∙∙∙Cl- Wiberg Bond orders and contributions from charge transfer (nCl- --> σ* C-X) are obtained...
January 3, 2017: Chemistry, An Asian Journal
Z Wen, J Wang, W Jiang, D O'Brien, G Sawakuchi, G Ibbott
PURPOSE: To investigate whether a strong magnetic field (B=1.5 T) can affect dose responses of thermoluminescent dosimeters (TLDs), optically stimulated luminescence dosimeters (OSLDs) and Gafchromic films using an MR-Linac (Elekta) before and after the magnet was ramped down from 1.5 T to 0 T. METHODS: Three types of dosimeters (TLDs, OSLDs, EBT3 films) were divided into two groups. Group 1 was first irradiated in a phantom of Solid Water slabs (Standard Imaging) inside a B=1...
June 2016: Medical Physics
M Bach, J Wulff
PURPOSE: Interference of dose application in scanned beam particle therapy and organ motion may lead to interplay effects with distorted dose to target volumes. Interplay effects depend on the speed and direction of the scanning beam, leading to fringed field edges (scanning parallel to organ motion direction) or over- and under-dosed regions (both directions are orthogonal). Current repainting methods can mitigate interplay effects, but are susceptible to artefacts when only a limited number of repaints are applied...
June 2016: Medical Physics
S McMahon, A McNamara, J Schuemann, K Prise, H Paganetti
Purpose Uncertainty in the Relative Biological Effectiveness (RBE) of heavy charged particles compared to photons remains one of the major uncertainties in particle therapy. As RBEs depend strongly on clinical variables such as tissue type, dose, and radiation quality, more accurate individualised models are needed to fully optimise treatments. MethodsWe have developed a model of DNA damage and repair following X-ray irradiation in a number of settings, incorporating mechanistic descriptions of DNA repair pathways, geometric effects on DNA repair, cell cycle effects and cell death...
June 2016: Medical Physics
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