Search results for "Mines"

Amphoteric, prevailingly cationic L-arginine polymers of poly(amidoamino acid) structure: Synthesis, acid/base properties and preliminary cytocompati…

2013

A linear amphoteric poly(amidoamino acid), L-ARGO7, is prepared by Michael-type polyaddition of L-arginine with N,N′-methylenebisacrylamide. Chain-extension of acrylamide end-capped L-ARGO7 oligomers with piperazine leads to high-molecular-weight copolymers in which L-arginine maintains its absolute configuration. Acid/base properties of L-ARGO7 polymers show isolectric points of ≈10 and positive net average charges per repeating unit at pH = 7.4 from 0.25 to 0.40. These arginine-rich synthetic polymers possibly share some of the unique biological properties of polyarginine cell-permeating peptides. In vitro tests with mouse embryo fibroblasts balb/3T3 clone A31 show that L-ARGO7 polymers a…

Amphoteric polyamidoamines in the treatment of malaria

2012

The present invention relates to the use of amphoteric polyamidoamines with MW of 10-100 kDa as antimalarial agents or carriers of antimalarial drugs and to formulations thereof.

Sequestration of biogenic amines by alginic and fulvic acids.

2006

The interaction of natural (alginic and fulvic acids) and synthetic (polyacrylic acid 2.0 kDa) polyelectrolytes with some protonated polyamines [diamines: ethylendiamine, 1,4-diaminobutane (or putrescine), 1,5-diaminopentane (or cadaverine); triamines: N-(3-aminopropyl)-1,4diaminobutane (or spermidine), diethylenetriamine; tetramine: N.N'-bis(3-aminopropyl)-1,4-diaminobutane (or spermine); pentamine: tetraethylene-pentamine; hexamine: pentaethylenehexamine] was studied at T=25 degrees C by potentiometry and calorimetry. Measurements were performed without supporting electrolyte, in order to avoid interference, and results were reported at I=0 mol L(-1). For all the systems, the formation of…

Improvements in Rational Design Strategies of Inulin Derivative Polycation for siRNA Delivery.

2016

The advances of short interfering RNA (siRNA)-mediated therapy provide a powerful option for the treatment of many diseases, including cancer, by silencing the expression of targeted genes involved in the progression of the pathology. On this regard, a new pH-responsive polycation derived from inulin, Inulin-g-imidazole-g-diethylenetriamine (INU-IMI-DETA), was designed and employed to produce INU-IMI-DETA/siRNA "Inulin COmplex Nanoaggregates" (ICONs). The experimental results showed that INU-IMI-DETA exhibited strong cationic characteristics and high solubility in the pH range 3-5 and self-aggregation triggered by pH increase and physiological salt concentration. INU-IMI-DETA showed as well…

Effect of Er3+-doping on 65GeS2-25Ga2S3-10CsCl glass probed by annihilating positrons

2019

Abstract Effect of Er3+-doping resulting in pronounced mid-IR fluorescence functionality was examined first in chalcohalide 65GeS2-25Ga2S3-10CsCl glass using positron annihilation lifetime (PAL) spectroscopy. The detected PAL spectra were reconstructed from unconstrained x2-term analysis employing two-state simple trapping model for one kind of positron trapping free-volume defects, the parameterization being performed at the example of 65GeS2-25Ga2S3-10CsCl glass doped with 0.6 at. % of Er3+. The observed decrease in positron trapping rate was proved to be primary void-evolution process in this Er-activated glass, like in many other chalcogenide glasses affected by rare earth doping. The n…

Challenges Associated with Byproducts Valorization—Comparison Study of Safety Parameters of Ultrasonicated and Fermented Plant-Based Byproducts

2020

In order to promote the efficient use of byproducts from the production of plant-based beverages, which still contain a large amount of nutritional and functional compounds, microbiological and chemical safety characteristics should be evaluated and, if needed, improved. Many challenges are associated with byproducts valorization, and the most important ones, which should be taken into account at the further steps of valorization, are biological and chemical safety. For safety improving, several technological treatments (biological, physical etc.) can be used. In this study, the influence of low-frequency ultrasonication (US) and fermentation with Lactobacillus casei LUHS210 strain, as phys…

Programmatūras izstrāde elementāro procesu noteikšanai no eksperimentāliem datiem

2019

Darba gaitā tika izveidota uz C++ bāzēta programmatūra, kura analizē zinātniskās iekārtas izvaddatus, iegūtus mērot cieto vielu fotoluminiscences no ātrām dzišanas kinētikām. Tiek izmantotas divas metodes datu aproksimācijai ar vienu un divām dilstošām eksponentēm. Lietotāja izvēlētie lokāli uzglabātie faili, kuri ir iegūti eksperimenta laikā, tiek apstrādāti ar dažādām darbībām pēc kurām rezultāti tiek uzrādīti kā vienādojuma mainīgās vērtības un atkarībā no metodes var būt izrakstīti failā kā datu punkti. Kvalifikācijas darbā tiek iekļauta programmatūras prasību specifikācija un programmatūras projektējuma apraksts ar testēšanas dokumentāciju.

Interaction of mushroom tyrosinase with aromatic amines, o-diamines and o-aminophenols

2004

3-Amino-L-tyrosine was found to be a substrate of mushroom tyrosinase, contrary to what had previously been reported in the literature. A series of amino derivatives of benzoic acid were tested as substrates and inhibitors of the enzyme. 3-Amino-4-hydroxybenzoic acid, 4-amino-3-hydroxybenzoic acid and 3,4-diaminobenzoic acid were oxidized by this enzyme, as previously reported for Neurospora crassa tyrosinase, but 4-aminobenzoic acid and 3-aminobenzoic acid were not. Interestingly, 3-amino-4-hydroxybenzoic acid was oxidized five times faster than 4-amino-3-hydroxybenzoic acid, confirming the importance of proton transfer from the hydroxyl group at C-4 position. All compounds inhibited the m…

Synthesis and biological evaluation of pyrrolo[3’,2’:6,7]cyclohepta[1,2-d]pyrimidin-2-amines

2014

Synthesis, Electrochemistry, and Photophysics of Aza-BODIPY Porphyrin Dyes

2016

International audience; The synthesis of dyad and triad aza-BODIPY-porphyrin systems in two steps starting from an aryl-substituted aza-BODIPY chromophore is described. The properties of the resulting aza-BODIPY-porphyrin conjugates have been extensively investigated by means of electrochemistry, spectroelectrochemistry, and absorption/emission spectroscopy. Fluorescence measurements have revealed a dramatic loss of luminescence intensity, mainly due to competitive energy transfer and photoinduced electron transfer involving charge separation followed by recombination.