The production conditions were optimized, and the characteristics of biodegradable chitosan-gelatin films crosslinked with various microbial transglutaminases (transglutaminase 1, which contains maltodextrin, and transglutaminase 2, which contains maltodextrin, a milk protein) were studied. The film properties depended on both the cross-linking conditions and the type and ratio of components in the mixture. Gels and films prepared from chitosan and gelatin with transglutaminase 1 had very low characteristics as compared to films obtained with transglutaminase 2. Infrared spectroscopy, X-ray tomography, and scanning atomic force electron microscopy showed that transglutaminase 2 forms cross-links between both gelatin and chitosan amino groups, which improves the film characteristics. Films prepared from chitosan, gelatin, and glycerol crosslinked with transglutaminase 2 had the following characteristics: a strength of 15.8 MPa, a tensile strength of 220.0%, a thickness of 73.1 μm, and a density of 1.9 g/cm3. The biodegradability of the films depended on the composition and ranged from 20 to 30 days. The resulting films can serve as a matrix to obtain medical materials with antibacterial and wound-healing properties.
It has been shown that the intensification of oxidative processes is observed when somatic nerves of rats are damaged. Accumulation of malondialdehyde occurs, and the phase properties of the lipid bilayer change, especially in the distal part of the nerve. Under the same conditions, there are multidirectional changes in the activity of antioxidant enzymes, superoxide dismutase (SOD) activity decreases, and catalase (CAT) activity increases. Under the action of resveratrol, there is a decrease in the number of TBA-active products in both areas of the damaged nerve. Alongside resveratrol action, SOD and CAT activity tends to return towards the control values. Similar patterns are observed in the action of resveratrol on the phase states of lipids with the damage to somatic nerves. By summarizing the data obtained, it can be claimed that when the nerve is damaged, profound changes occur both in the lipid component and in the antioxidant system. Resveratrol has a stabilizing effect on the studied parameters, and a longer period of time is required for their complete recovery.
24 February 2015 in International Journal of Hematology
This study looked into the synthesis and study of Dextrane Sulfate–Doxorubicin Nanoparticles (DS–Dox NP) that are sensitive to amylase and show anticoagulant properties. The particles were obtained by the method of solvent replacement. They had a size of 305 ± 58 nm, with a mass ratio of DS:Dox = 3.3:1. On heating to 37 °C, the release of Dox from the particles was equal to 24.2% of the drug contained. In the presence of amylase, this ratio had increased to 42.1%. The study of the biological activity of the particles included an assessment of the cytotoxicity and the effect on hemostasis and antitumor activity. In a study of cytotoxicity on the L929 cell culture, it was found that the synthesized particles had less toxicity, compared to free doxorubicin. However, in the presence of amylase, their cytotoxicity was higher than the traditional forms of the drug. In a study of the effect of DS–Dox NP on hemostasis, it was found that the particles had a heparin-like anticoagulant effect. Antitumor activity was studied on the model of ascitic Zaidel hepatoma in rats. The frequency of complete cure in animals treated with the DS–Dox nanoparticles was higher, compared to animals receiving the traditional form of the drug.
In this paper, the erythrocytes of healthy donors and people with a confirmed diagnosis of COVID-19 were tested by Raman spectroscopy and laser interference microscopy. We argue that erythrocytes (red blood cells) in COVID-19 patients have an irregular shape, and their morphometric characteristics are impaired in comparison to healthy red blood cells. Raman spectroscopy also allows us to detect a decreased oxygen transport function of these erythrocytes. The combination of these methods—Raman spectroscopy and laser interference microscopy—is a highly effective method for the diagnosis of SARS-CoV-2.