Enhancing the Solubility, Stability, and Bioavailability of Retinol Acetate through Mechanochemistry.

This study utilizes mechanochemistry to prepare retinol acetate (RA) solid dispersion (RA-sodium starch octenyl succinate (SSOS)), resulting in improved solubility, stability, and bioavailability compared with raw RA and commercial RA microcapsules. RA, poloxamer 188, SSOS, and milling beads (8 mm) were mixed in a ratio of 2:1:8:220 (w/w) and ball-milled at 100 rpm for 3 h. RA-SSOS exhibited a solubility of 1020.

Cytotoxicity and Degradation Resistance of Cryo- and Hydrogels Based on Carboxyethylchitosan at Different pH Values.

The use of chitosan-based gels is still limited due to their restricted solubility in acid solutions, where the molecules have a positive charge. The functionalization of chitosan makes it possible to significantly expand the possibilities of using both the polymer itself and hydrogels based on its derivatives. To evaluate the effect of the conditions for the production of cryo- and hydrogels based on carboxyethylchitosan (CEC) crosslinked with glutaraldehyde on gel swelling and its resistance to degradation depending on pH and cytotoxic effects and to test the hypothesis that the amount of crosslinking agent during synthesis may affect the cytotoxicity of the gel.

A Carboxyethylchitosan Gel Cross-Linked with Glutaraldehyde as a Candidate Carrier for Biomedical Applications.

To date, few publications describe CEC's properties and possible applications-thus, further evaluation of these properties is a point of interest. The present in vitro model study aimed to evaluate a carboxyethylchitosan (CEC) gel with a degree of substitution of 1, cross-linked with glutaraldehyde at a polymer:aldehyde molar ratio of 10:1, as a potential carrier for delivering bacteriophages to various pH-fixed media (acidic, alkaline), and including gastrointestinal tract (GIT) variable medium. A quantitative analysis of bacteriophages released from the gel was performed using photon correlation spectrophotometry, and phage activity after emission into medium was evaluated using the spot test.

Holmium complex with phospholipids as H NMR temperature probe for membrane systems.

The temperature dependence of the lanthanide-induced chemical shifts (LISs) was studied for the systems containing 1-palmitoyl-2-oleoylphosphatidylcholine (POPC)-Ho, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC)-Ho and 1,2-dimyristoyl-sn-glycero-3-phosphorylcholine (DMPC)-Ho in unilamellar liposomes. In the POPC-Ho system, anti-Curie dependence of LISs is observed, same as previously observed in POPC-Pr system. In the DPPC- and DMPC-Ho systems, temperature features are observed which are probably connected with phase transition.

Preparation and Characterization of a Glycyrrhizic Acid-Based Drug Delivery System for Allergen-Specific Immunotherapy.

The most effective method of treating allergic diseases, aimed not at relieving symptoms, but at eliminating the cause of the disease, is allergen-specific immunotherapy (AIT). To reduce the risk of side effects and improve the delivery of allergens to the mucosa, various delivery systems, such as liposomes, dendrimers, nanoparticles, etc., can be used.

Effect of Glycyrrhizic Acid and Arabinogalactan on the Membrane Potential of Rat Thymocytes Studied by Potential-Sensitive Fluorescent Probe.

The effect of the natural saponin glycyrrhizic acid (GA) and polysaccharide arabinogalactan (AG) on the transmembrane potential of rat thymocytes was investigated using the potential-sensitive fluorescent probe 4-(p-dimethylaminostyryl)-1-methylpyridinium (DSM). Incubation of cells with GA in micellar form resulted in a decrease of the amplitude of observed fluorescence kinetics that points out to a decrease of the transmembrane potential. The proposed mechanism is an increase of membrane ion permeability (passive ion transport) of the plasma cell membrane due to GA incorporation.

Enhancement of COPD biological networks using a web-based collaboration interface.

The construction and application of biological network models is an approach that offers a holistic way to understand biological processes involved in disease. Chronic obstructive pulmonary disease (COPD) is a progressive inflammatory disease of the airways for which therapeutic options currently are limited after diagnosis, even in its earliest stage. COPD network models are important tools to better understand the biological components and processes underlying initial disease development.

How to estimate multislice CT effective dose more correctly.

The purpose of this paper is to provide data concerning differences in multislice CT effective dose estimation when using various methods and techniques, determine the reasons for these differences, and submit proposals for improving the estimation accuracy. All the experiments (chest and head exam settings) were conducted using 64-slice CT scanners from various manufacturers. Effective dose estimates have been obtained on the basis of the conventional dose-length product method, absorbed dose distribution curves, and using anthropomorphic phantoms with thermoluminescent dosimeters as a model method.

[Hardware-software system for monitoring parameters and characteristics of X-ray computer tomographs under operation conditions].

The results of testing of hardware and software for monitoring parameters (mean number of CT units, noise, field uniformity, high-contrast spatial resolution, layer width, dose) and characteristics (modulation transfer function) of X-ray computer tomographs are presented. The developed hardware and software are used to monitor the stability of X-ray computer tomograph parameters under operation conditions.

[Analysis of factors affecting the results of estimation of the detective quantum efficiency of digital X-ray detectors within high and low spatial frequency ranges].

Factors affecting the results of estimation of the detective quantum efficiency of digital X-ray detectors within high and low spatial frequency ranges are studied. These factors include energy dispersion and loss in the conversion channel, nonuniformity of the X-ray detector irradiation field, and the internal noise of the system.

[Analysis of frequency-contrast characteristics of digital X-ray image detectors].

The effect of various computing procedures on the results of estimation of parameters used for MTF calculation is analyzed. Experimentally evaluated modulation transfer functions of some types of digital X-ray image detectors are presented.

[Experimental and computational evaluation of quality of digital X-ray imaging].

The results of the use of specialized software for experimental and computational evaluation of the characteristics of digital X-ray detectors are analyzed.

[Experience in the use of a test phantom for checking the biopsy needle position in stereotactic mammography].

The possibility of the use of a special test phantom for checking the biopsy needle positioning accuracy in mammographic stereotactic devices is discussed. The test phantom meets the requirements of the state standard GOST R50267.45.

[The results of the monitoring of characteristics of digital receivers for X-ray images by using enterprise (VNIIMT) reference standard 01-22-04].

Described are the results of testing of methods of the new 01-22-04 standard designed for monitoring the image-quality parameters of digital X-ray converter-receivers (made alongside with tests of digital X-ray diagnostic units ProScan-7000 and ProScan-2000).

[Correlation of noises in the channels of digital X-ray receiver-transformer and the evaluation of registration's quant efficiency].

Theoretical and experimental research results related with the influence of correlation of signals in neighboring elements of digital X-ray receiver-transformer produced on the evaluation of the output ratio noise/signal and, as a consequence, on the evaluation of quantum registration efficiency are described in the paper.

[An experience in using a formalized protocol in describing digital fluorograms].

The case study deals with designing the formalized flow for digital photofluorogram and with results of their clinical testing. Recommendations are defined for improving the protocol program.

[Specific features of monitoring the characteristics of digital X-ray diagnostic systems].

The paper analyzes the specific features of monitoring the basic characteristics of formation of images in the digital X-ray diagnostic systems and considers the potentialities of transfer from traditional expert assessments to more objective and precise experimentally calculated methods.

[Test object for controlling the quality of orthopantomography].

Great emphasis is placed on a FO-01 orthopantomographic phantom test for checking the position of the projection boundary of an isolated layer, its shape and thickness. The basic specific feature of the phantom test is that one can rather simply check the adjustment of orthopantomographs of different kinds (including digital ones) and make their comparative assessment by the projection of an isolated layer with certain resolution. Examples of projection nomograms of an isolated layer for different orthopantomographs, which are obtained by this test object are given.