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References B ANDYOPADHYAY , P. , G HOSH , A.K. & G HOSH , C. ( 2012 ): Recent developments on polyphenol–protein interactions: effects on tea and coffee taste

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For studying the thermal disproportionation and interaction processes of niobium bromides in the NbBr5-Nb system thermoanalytical and tensimetric methods were employed. The study revealed that the reduction of niobium pentabromide by metallic niobium starts at 257°C and leads to the formation of niobium tetrabromide. The temperature limits of the existence of bromides of niobium in lower oxidation states were determined.

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175 183 Annicchiarico, P. (2002): Genotype × environment interactions — Challenges and opportunities for plant breeding and cultivar recommendations. FAO Plant Production and Protection

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Abstract  

Dipalmitoylphosphatidylcholine (DPPC) liposomes were employed as membrane models for the investigation of the interaction occurring between methotrexate (MTX) and bilayer lipid matrix. Liposomes were obtained by hydrating a lipid film with 50 mM Tris buffer (pH 7.4). The differential scanning calorimetry (DSC) evaluation of the thermotropic parameters associated with the phase transitions of DPPC liposomes gave useful information about the kind of drug-membrane interaction. The results showed an electrostatic interaction taking place with the negatively charged molecules of MTX and the phosphorylcholine head groups, constituting the outer part of DPPC bilayers. No interaction with the hydrophobic phospholipid bilayer domains was detected, revealing a poor capability of MTX to cross through lipid membranes to reach the interior compartment of a lipid bounded structure. These findings correlate well within vitro biological experiments on MTX cell susceptibility.

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Abstract  

In the course of the formulation of coated dosage forms, the selection of the suitable composition of the coating system is of great importance in respect of the final dosage form. Since the applied coating systems are multicomponent, the possible interactions between the components determine the physico-chemical stability of the formulated dosage form, the drug release process, as well as the formulation parameters. In the present study, the influence of the applied plasticizer, dibutyl sebacate on the enthalpy relaxation of casted Eudragit L 30D films was determined as a function of the plasticizer concentration. The enthalpy relaxation was recorded by DSC during the applied isothermal recovery process of Eudragit films. The obtained results indicate that enthalpy relaxation can be measured by DSC at 20 mass/mass% dibutyl sebacate concentration, which refers to the increased molecular mobility consequently to the effect of the interaction between the polymer and plasticizer.

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Journal of Thermal Analysis and Calorimetry
Authors: H. Razafindralambo, S. Dufour, M. Paquot, and M. Deleu

Abstract  

Isothermal titration calorimetry was applied for studying the binding interactions of cyclic and linear surfactins with different ionic charge (z= −2 and −3) and lipid chain length (n=14 and 18) to 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidyl-choline (POPC) vesicles in 10mMTris buffer at pH8.5with 150mMNaCl at 25°C. Surfactin analogues interacted spontaneously (ΔG D w→b < 0) with POPC vesicles. The binding reactions were endothermic (ΔH D w→b > 0) and entropy-driven process (ΔS D w→b > 0). Moreover, significant differences in the binding constant values (K) ranging from 6.6·103 to 9.6·104 M−1 show that cyclic structure and the increase of lipid chain length are favourable on the surfactin binding affinity to POPC vesicles, whereas the rise of the number of negative charges has an opposite effect.

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Abstract  

To clarify the mechanism of the hemolytic activity of 4-META− (4-methacryloyloxyethyl trimellitate anhydride), an evaluation of the interaction of 4-META and its related compounds (4-MET; phthalic anhydride, PAN; and phthalic acid, PA) with DPPC liposomes using a DSC and NMR spectroscopy is presented. Changes in NMR chemical shifts, phase transition temperatures and broadening of the main transition induced by 4-META and PAN were greater than those induced by 4-MET and PA. The order of decreasing interactions is as follows: 4-META>PAN>4-MET>PA. Ionized compounds such as 4-MET and PA did not interact with erythrocyte membranes.

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Abstract  

The present investigation was carried out to screen compatibility of some diluents with pefloxacin mesilate using differential scanning calorimetry (DSC), isothermal stability studies, along with stability studies in liquid state and to assign relative ranking to diluents. Compatibility was predicted with MCC101, MCC102, DCP anhydrous, Emcompress, while melting endotherm of drug was lost in admixtures of dextrose anhydrous, Pearlitol, Lactopress spray dried, Lactochem fine powder and Lycatab indicating possibility of interaction. Enthalpy changes were used for relative ranking of diluents.

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The theory of âeœcodon-amino acid coevolutionâe? was first proposed by Woese in 1967. It suggests that there is a stereochemical matching - that is, affinity - between amino acids and certain of the base triplet sequences that code for those amino acids. We have constructed a Common Periodic Table of Codons and Amino Acids, where the Nucleic Acid Table showed perfect axial symmetry for codons and the corresponding Amino Acid Table also displayedperiodicity regarding the biochemical properties (charge and hydrophobicity) of the 20 amino acids and the position of the stop signals. The Table indicates that the middle (2 nd) amino acid in the codon has a prominent role in determining some of the structural features of the amino acids. The possibility that physical contact between codons and amino acids might exist was tested on restriction enzymes. Many recognition site-like sequences were found in the coding sequences of these enzymes and as many as 73 examples of codon-amino acid co-location were observed in the 7 known 3D structures (December 2003) of endonuclease-nucleic acid complexes. These results indicate that the smallest possible units of specific nucleic acid-protein interaction are indeed the stereochemically compatible codons and amino acids.

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Varga, K., Bányai, E. I. , & Gősi-Greguss, A. Cs. (1994). Parallel application of the experiential analysis technique with subject and hypnotist: A new possibility for measuring interactional synchrony. International Journal of Clinical and

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