In this article, we examined a high-performance, environmentally friendly method for producing composite films based on starch and natural rubber latex (NR). To increase the compatibility of the components, the casting dispersions were subjected to short-term (10 s) mechanical activation in a rotor-stator device. Using the rotational viscosimetry method, it was found that mechanical activation reduces the structuring degree and the effective viscosity of the casting dispersions.
View Article and Find Full Text PDFThe development of novel biocompatible and biodegradable materials for medical applications has been drawing significant interest in the scientific community for years. Particularly, chitosan loaded with silver nanoparticles (Ag NPs) has a strong antimicrobial potential and could be applied, for example, as wound dressing material. In this work, chitosan/Ag NP composites were produced utilizing a single-step plasma-solution process, which is simple and environmentally friendly.
View Article and Find Full Text PDFThe effect of composition and mechanoactivation in the rotor-stator device on the rheological and film-forming properties of casting blends based on corn starch and chitosans with high (HDC) and low (LDC) deacetylation degree was studied. Films were characterized using optical and atomic force microscopy, X-ray diffraction, FTIR-spectroscopy and by tensile and moisture permeability testing data. An increase in chitosan content was found to result in the blends viscosity increase as well as the tensile strength, elongation and moisture permeability of films.
View Article and Find Full Text PDFInt J Biol Macromol
October 2019
A new process of mechanically initiated formation of chitosan physical hydrogels in aqueous solution, without a cross-linking agent, was studied. Physical hydrogel is formed by mechanical activation of solutions of chitosan with a low deacetylation degree (58%) in situ in a rotor-stator device for 10 s. The formation of 3D gel structure has been proven by rotational viscometry and dynamic rheometry methods.
View Article and Find Full Text PDFIn this work, we studied the structural, morphological and chemical transformations in α- chitin, caused by its mechanical activation in the form of an aqueous suspension in the rotor-stator device for 5-30 s. Mechanically activated chitin (MA-chitin) was characterized using optical and electron scanning microscopy, N adsorption/desorption isotherms, X-ray diffraction and FTIR-spectroscopy. It was established that the specific surface area, porosity and the deacetylation degree of chitin increase with increasing processing time, and the decrease in crystallinity and reducing the packing density of macromolecular chains does not correlate with this indicator due to the development of recrystallization.
View Article and Find Full Text PDFThe method of mechanical activation in the rotor-stator device was used to combine the starch hydrogel and the latex of the synthetic copolymer. The compatibility of the components was found to improve consistently by the preliminary mechanoactivation of the starch gel and the joint activation of the mixturs. The joint activation was shown to promote the crystallization of starch and the amorphous phase ordering of the composite.
View Article and Find Full Text PDFPatol Fiziol Eksp Ter
December 2017
Methods: Experiments were carried out on outbred albino male rats (n = 150, 230-250 g). For modeling dislipoproteinemia (DLP) we used 3 models: single intraperitoneal injection of the detergent triton WR-1339; administration of ethanol; maintenance on a special hypercholesterolaemic diet (HD) during 21 days. Animals were divided into four groups: normal control, model group, gemfibrozil (Gfb) group, benzohexonium (Benz) group.
View Article and Find Full Text PDFWe have found that N-cholinolytic drug benzohexonium produces a hypolipidemic effect: it reduces dyslipoproteinemia, fatty infiltration of the liver, and risk of atherosclerotic lesions.
View Article and Find Full Text PDFThe efficacy of a combined therapy with reminyl and ovestin in low doses used for pharmacocorrection of cognitive disorders in women after total ovariectomy has been studied. The results show a pronounced efficacy of the proposed combined therapy as compared to the standard hormonal replacement therapy in women with hypoestrogenic syndrome, which is confirmed by a significant decrease in the expression of mental impairments evaluated using the BCRS, CCSE, and MMSE methods.
View Article and Find Full Text PDFEffects of methacine, hexamethonium and their combinations with neostigmine on activity of B-lymphocytes in various phases of immune response and development of stress ulcers induced in animals were studied. The drugs were found to modulate B-lymphocyte activity for 28 days and longer. By a water-immersion stress model it was shown that methacin is effective not only as m-cholinolytic but also as an immunoprophylactic drug reducing destructive changes in gastric mucosa.
View Article and Find Full Text PDFAnesteziol Reanimatol
September 2007
The agents containing succinic and fumaric acids were used to control body temperature during an operation. Elective surgical interventions into small pelvic organs were made in 22 females aged 28-55 years, who were divided into 2 groups. In group 1 (n = 11), the agents containing succinic and fumaric acids were used and infusion therapy that did not differ from Group 2 (n = 11) in all other respects.
View Article and Find Full Text PDFChronic combined administration of 5-HT1A receptor antagonist NAN-190 and 17beta-estradiol improved conditioned passive avoidance performance in middle-aged ovariectomized rats with scopolamine-induced amnesia. Our results suggest that the ovarian hormonal, cholinergic, and serotoninergic systems play a role in age-related cognitive disturbances under conditions of hypoestrogenic syndrome.
View Article and Find Full Text PDFThe role of acetylcholine and the cholinergic system in non-neuronal cells (in particular, in lymphocytes) in humans is considered. Lymphocytes express most of the cholinergic components found in the nervous system, which makes possible acetylcholine-dependent stimulation of lymphocytes in the spleen and lymph nodes. The sympathetic innervation and paracrine mediators control several immune cell functions, the blood perfusion, lymphoid cells and antigen uptake by the lymphoid organs.
View Article and Find Full Text PDFThe effect of chronic combined treatment with galantamine and 17beta-estradiol on passive avoidance retention was studied in middle-aged ovariectomized female rats (15 months) with scopolamine-induced amnesia. Combined treatment with galantamine and estradiol completely restored retrieval of memory traces in middle-aged ovariectomized female rats.
View Article and Find Full Text PDFThe effect of chronic (14 days) administration of the serotonin 5-HT(1A) receptors agonist 8-OH-DPAT (0.05 mg/kg, s.c.
View Article and Find Full Text PDFThe investigation of acetylcholine-dependent regulation of the model anaphylaxic shock in guinea pigs showed that an increase in the concentration of endogenous acetylcholine in sensitized animals leads to an increase in the agonal shock period (by 15 +/- 1 min in the test and 3 +/- 1 min in the control) and abolishes shock in the pathochemical phase: anaphylactic index 0.4 +/- 0.02 in the test against 4 +/- 0.
View Article and Find Full Text PDFThe results of experiments on mice showed that some imidazole-4,5-dicarboxylic acid derivatives injected into lateral cerebral ventricles produce a dose-dependent convulsant or anticonvulsant effects, that is, possess the properties of partial NMDA receptor agonists. The most promising partial NMDA receptor agonist selected for further investigation is 2-propylimidazole-4,5-dicarboxylic acid.
View Article and Find Full Text PDFOcclusion of the left coronary artery in rats provoked ventricular tachycardia (VT) and ventricular fibrillation (VF) within the first 30 min of ischemia leading to death in 20% animals. Methacin (i.v.
View Article and Find Full Text PDFNeurosci Behav Physiol
January 2001
The characteristics of cholinoreceptors located on neurons TAN1, TAN2, and TAN3 of the ground snail Achatina fulica were studied by incubation of the central ganglia in a bath with cholinotropic preparations during intracellular recording of background neuron spike activity. Acetylcholine, nicotine, the selective n-cholinoreceptor agonist suberyldicholine, and the selective n-cholinoreceptor agonist 5-methylfurmethide concentration-dependently inhibited background spike activity to the level of complete blockade at concentrations of 500 microM. The m-cholinoblocker metamizil (500 microM) completely prevented the inhibitory activity of concentrations of 5-methylfurmethide of up to 500 microM.
View Article and Find Full Text PDFRoss Fiziol Zh Im I M Sechenova
April 1999
Acetylcholine, nicotine, a selective agonist of N-cholinoreceptors suberildicholine dibromide, as well as a selective agonist of M-cholinoreceptors 5-methylfurmethide inhibited spike discharges in a dose-dependent manner up to a complete ceasing of the firing in cholinoreceptors situated on the identified neurone TAN of African giant snail Achatina fulica. M-cholinoblocker metamizylum completely prevented the inhibitory effect of methylfurmethide. Central cholinoblocker aetherophen completely prevented the inhibitory effect of suberildicholine dibromide.
View Article and Find Full Text PDFExperiments on 25 intact dogs, 2 calves and clinical tests in 45 patients have shown that in the blood of the aorta or pulmonary vein leaving the lungs there is a rise in generation of active oxygen forms by leukocytes, their phagocytic activity, the activity of myeloperoxidase, NADPN-oxidase, complement, immunoglobulins content. As to the liver, kidneys, spleen, no such increased generation of active oxygen forms by leukocytes was registered. The results suggest an important role of the lungs in regulation of free radical activity of leukocytes, their phagocytic ability and thus in anti-infection defense of the body.
View Article and Find Full Text PDFThe authors studied the effect of m-cholino-, adreno-, and purinotropic agents on the development of postischemic reperfusion fibrillation of isolated rat hearts. Pilocarpine, norepinephrine, phenylephrine, and adenosine caused a proarrhythmogenic effect. Atropine, trimedoxim, prazosin, and chloroquine made fibrillation less expressed.
View Article and Find Full Text PDFFiziol Zh Im I M Sechenova
June 1994
Rat experiments have indicated that increased lipid peroxidation in gastric tissue occurs with formation of cryogenic gastric ulcers. The use of methacin alone, 1 mg/kg i.p.
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