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Abstract  

The new mixed ligand complexes with formulae M(4-bpy)(C2H5COO)22H2O (where M(II)=Mn, Co, Ni; 4,4'-bpy or 4-bpy=4,4'-bipyridine) and Cu(4-bpy)0.5(C2H5COO)2H2O were prepared and characterized by VIS (for solid compounds of Co(II), Ni(II), Cu(II) in Nujol), IR spectroscopy, X-ray powder diffraction and molar conductance in MeOH, DMF or DMSO. Thermal behaviour of complexes was studied under static conditions in air atmosphere. Corresponding metal oxides were identified as final products of pyrolysis. A coupled TG-MS system was used to analysis of principal volatile thermal decomposition and fragmentation products of isolated complexes under dynamic air and argon atmosphere. The principal species correspond to: C+, OH+, H2O+, NO+, CO2 + and other; additionally CO+ in argon atmosphere.

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Abstract  

Four new mixed ligand complexes were prepared by the reaction of title metal dichloroacetates and 2,4'-bipyridine. The general formulae of synthesized compounds are M(2,4'-bpy)2(CCl2HCOO)2 nH2O (where M(II)=Mn, Co, Ni, Cu; 2,4'-bpy=2,4'-bipyridine, n=2 or 4). The complexes have been isolated from aqueous media and characterized by chemical analysis, molar conductance (in MeOH, DMSO and DMF), magnetic, IR and VIS spectral studies. The nature of metal(II)-ligand coordination is discussed. The thermal behaviour of obtained complexes was studied by thermal analysis and TG-MS techniques in air. IR, X-ray powder diffraction and thermoanalytical data were used for the determination of solid intermediate products of the thermal decomposition. The principal volatile products of thermal decomposition of complexes were proved by mass spectroscopy: H2O+, CO+ 2, HCl+ 2, Cl+ 2, NO+ and other.

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The synthetic scope of photo-induced copper-mediated polymerization (photoCMP) in continuous-flow reactors is further explored. A series of monomers, namely, methyl (MA), ethyl (EA), n-butyl (nBA), 2-hydroxyethyl (HEA), and di(ethylene glycol) ethyl ether (DEGA) acrylate are investigated, all showing high livingness (dispersity in the range of 1.1 and linear first order kinetics) in the polymerizations and high conversions within 20-min reaction time. Next to the commonly used solvent (dimethyl sulfoxide [DMSO]), also a water—ethanol mixture was used as greener alternative, without any loss in reaction control. Upscaling the reactor from 2 to 16 mL allows for production of over 200 g of high-definition material (3000 g/mol, 1.1 dispersity) in overnight operation (18 h), demonstrating that the photoprocess can be run under very stable conditions even for extended reaction times. Via coupling of two reactors, direct chain extension of copolymers in a single reaction step is also demonstrated.

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Abstract  

A combined analysis of structural data and experimental results (DSC, temperature-resolved XRPD and hot stage optical microscopy) revealed that the dehydration mechanism of cortisone acetate monohydrate (CTA·H2O) involves a collective and anisotropic departure of water molecules followed by a cooperative structural reorganization toward the anhydrous polymorph CTA (form 2). In spite of the lack of crystal structure data, it can be postulated from experimental data that thermal decomposition of the dihydrated form (CTA·2H2O) and of the tetrahydrofuran solvate (CTA·THF) toward another polymorph (CTA (form 3)) also proceeds according to a cooperative mechanism, thus giving rise to probable structural filiations between these crystalline forms of CTA. The crystal structure determination of two original solvates (CTA·DMF and CTA·DMSO) indicates that these phases are isomorphous to the previously reported acetone solvate. However, their desolvation behaviour does not involve a cooperative mechanism, as could be expected from structural data only. Instead, the decomposition mechanism of CTA·DMF and CTA·DMSO starts with the formation of a solvent-proof superficial layer, followed by the partial dissolution of the enclosed inner part of crystals. Hot stage optical microscopy observations and DSC measurements showed that dissolved materials (resulting from a peritectic decomposition) is suddenly evacuated through macroscopic cracks about 30°C above the ebullition point of each solvent. From this unusual behaviour, the necessity to investigate rigorously the various aspects (thermodynamics, kinetics, crystal structures and physical factors) of solvate decompositions is highlighted, including factors related to the particular preparation route of each sample.

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Absztrakt

A daganatos betegek kezeléséhez a kemoterápiás kezelések által kiváltott különböző mukokután reakciók társulhatnak. Az egyik ilyen mukokután mellékhatás a beadás helyén jelentkező toxikus szöveti reakció, az extravazáció, mely az összes citotoxikus infúzió kevesebb mint 1-2%-ában fordul elő. A hólyaghúzók által okozott extravazáció standard ellátása a következő: le kell állítani az infúziót, vissza kell szívni a gyógyszert, fel kell polcolni a végtagot, hűtést vagy éppen meleg kötést kell alkalmazni, helyi érzéstelenítést lehet végezni, antidotumokat kell adni (alkilező szerek esetén Na-tioszulfát, anthracyclinek és mitomycin esetén dimetilszulfoxid (DMSO), vinca-alkaloidák esetén hialuronidáz jön szóba), végső esetben viszont sebészi eltávolítás és plasztikai rekonstrukció szükséges. Mivel az anthracyclinek topoizomeráz II-mérgek, hatásukat a topoizomeráz II katalitikus gátlója (a dexrazoxan) antagonizálja, ezért a doxorubicin, epirubicin, daunorubicin stb. extravazációja esetén a dexrazoxan azonnali használata látszik a választandó kezelésnek. Az esemény után azonnal beadott egyetlen szisztémás dexrazoxan-adag jelentősen csökkentheti a toxikus szöveti károsodást. GM-CSF-injekciók ismételt intralézionális adása meggyorsíthatja a sebgyógyulást és elkerülhető a bőrpótlás.

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The intermediates formed from Mo(NO)2Cl2 L 2 and Mo(NO)Cl3 L 2 by splitting-off of weakly-coordinated ligandsL (alcohols, glycols, nitriles) decompose in exothermic reactions: the decomposition products are N2, MoOCl4 and MoO3. If the ligandL is strongly coordinated and is reducing (DMFA, DMSO, Pph3, Asph3), the NO groups oxidize the ligandL by formation of N2 in an exothermic intramolecular redox process under 300‡. The central atom is oxidized by NO, and N2O is formed above 300‡ in the case of non-reducing ligandsL (OPph3, OAsph3). An endothermic redox reaction with chlorine formation is observed during decomposition of the trichloro complex. The solid residue is metallic molybdenum.

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Cereal Research Communications
Authors: L. Brindzová, M. Zalibera, T. Jakubík, M. Mikulášová, M. Takácsová, S. Mošovská, and P. Rapta

This study examined the mutagenic, antimutagenic and antioxidant activities of the DMSO extracts from the wheat bran. Wheat bran extracts showed no genotoxicity toward Salmonella typhimurium TA98, TA100 and TA102 with or without S9 mix (an external metabolic system). In addition, wheat bran extracts expressed a dose-depend inhibitory effect on the mutagenicity of promutagen aflatoxin B1 (AFB1), an indirect mutagen which requires metabolic activation, and 3-(5-nitro-2-furyl)acrylic acid (5-NFAA), 2-nitrofluorene (2NF) and hydrogen peroxide (H 2 O 2 ), direct mutagens, in Salmonella typhimurium TA98, TA100 and TA102 strains. Significant total antioxidant capacity of wheat bran extract was found by two standard spectroscopic assays based on ABTS and DPPH reagents. A special attention was focused to the reactive radical scavenging capacity of bran extract as one of its antioxitant activities. Wheat bran extract possessed higher ability to scavenge oxygen- and carbon-centered reactive radicals generated by the thermal decomposition of K 2 S 2 O 8 than BHT (70 and 65% scavenged radicals, respectively) during the electron paramagnetic resonance (EPR)/spintrapping test. The total phenolic content of wheat bran samples expressed in gallic acid equivalent was 2.7 mg/g, total flavonoid content expressed in rutin equivalent was 70.8 μg/g and the most abundant phenolic acids established by GC-MS method were isoferulic (3-hydroxy-4-metoxycinnamic) and ferulic (4-hydroxy-3-metoxycinnamic) acid, sinapic, caffeic, p -coumaric and vanillic acids.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: S. Hayami, T. Kawahara, G. Juhász, K. Kawamura, K. Uehashi, O. Sato, and Y. Maeda

Abstract  

The magnetic properties of the spin-crossover compound, [Fe(qsal)2]NCSe·2DMSO (N-(8-quinolyl)-salicyladimine) (1), have been measured. We have discovered that the compound 1 exhibits a wide "thermal hysteresis loop" of 115 K (T1/2 = 324 K and T1/2 = 209 K) in the first cycle. Thermogravimetric analysis shows that solvent molecules of the compound 1 are removed at around 324 K. This means that the hysteresis loop observed for the first cycle is only an apparent one. Following the first loop, the compound 1 shows a spin-crossover in warming mode. The spin transition occurs at T1/2 = 285 K and T1/2 = 209 K and the hysteresis width can be estimated to be 76 K, which is one of the largest values reported so far for spin-crossover compounds. It is thought that the cooperativity produced in the compound mainly arises from the intermolecular interactions between the quinoline and the phenyl rings.

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Acta Physiologica Hungarica
Authors: A. Moslehi, Fatemeh Nabavizadeh, A.R. Dehpou, S.M. Tavanga, G. Hassanzadeh, A. Zekri, H. Nahrevanian, and H. Sohanaki

Endoplasmic reticulum (ER) stress provides abnormalities in insulin action, inflammatory responses, lipoprotein B100 degradation and hepatic lipogenesis. Excess accumulation of triglyceride in hepatocytes may also lead to disorders such as non-alcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH). Opioid peptides are involved in triglyceride and cholesterol dysregulation, inflammation and cell death. In this study, we evaluated Naltrexone effects on ER stress induced liver injury. To do so, C57/BL6 mice received saline, DMSO and Naltrexone, as control groups. ER stress was induced by tunicamycin (TM) injection. Naltrexone was given before TM administration. Liver blood flow and biochemical serum analysis were measured. Histopathological evaluations, TNF-α measurement and Real-time RT-PCR were also performed. TM challenge provokes steatosis, cellular ballooning and lobular inflammation which significantly reduced in Naltrexone treated animals. ALT, AST and TNF-α increased in the TM group and improved in the Naltrexone plus TM group. Triglyceride and cholesterol levels decreased in TM treated mice with no increase in Naltrexone treated animals. In the Naltrexone plus TM group, gene expression of Bax/Bcl-2 ratio and caspase3 significantly lowered compared with the TM group. In this study, we found that Naltrexone had a notable alleviating role in ER stress induced steatosis and liver injury.

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Transition metal(II) ions with dinegative tetradentate schiff base

Synthetic, thermal, spectroscopic and coordination aspects

Journal of Thermal Analysis and Calorimetry
Authors: H. Parekh, P. Panchal, and M. Patel

Abstract  

Some new coordination polymers of Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II), obtained from the interaction of metal acetate with dipotassium salt of N,N’-di(carboxyethylidene)terephthalaldehydediimine (K2SB) are described. The products, which have been characterized by elemental analyses, magnetic measurements, thermogravimetric analyses, electronic and infrared spectral studies, have composition, [M(SB)(H2O)2]n. These colored coordination polymers are non-hygroscopic and quite stable at room temperature. On the basis of analytical data and IR studies, a 1:1 metal to ligand stoichiometry has been suggested to these coordination polymers. The IR studies have also revealed that ligands are coordinated to metal ion through carboxy oxygen and azomethine nitrogen. All the studies suggested tetradentate nature of the ligand with octahedral symmetry of the coordination polymers. All the coordination polymers are insoluble in acetone, ethanol, chloroform, methanol, benzene, DMF and DMSO. The thermal decomposition of the coordination polymers is studied and indicates that not only the coordinated water is lost but also that the decomposition of the ligand from the coordination polymers is necessary to interpret the successive mass loss.

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