Comparative Study of the Mucoadhesive Properties of Polymers for Pharmaceutical Use

BACKGROUND: In recent years, mucoadhesive dosage forms due to their advantages have attracted the interest of researchers and developers. Polymeric excipients are included into the drug composition to give adhesion to the mucous membrane. AIM: The aim of this research was to select a specific brand of pharmaceutical quality polymer that is promising for inclusion in the drug formulation. METHODS: The article presents the results of studying the mucoadhesive properties of polymers on two models using mucin: By measuring the amount of adhesion and by the evaluation the sample movement speed. RESULTS: According to the combination of two indicators, the highest mucoadhesive properties were shown by the brands of hydroxypropylmethylcellulose and xanthan gum. In addition, it was noted that hydroxyethylcellulose (HEC), sodium alginate, and hydroxypropylmethylcellulose (HPMC) also have good mucoadhesive properties. Polyethylene glycols proved to have the weakest mucoadhesive properties. The negative relationship between the average molecular weight and the sample movement speed of the HEC and HPMC was established. Obtained data showed no direct influence of the polymer average molecular weight on the amount of adhesion. It was also noted that there is no strong correlation between the amount of adhesion and the sample movement speed of the experimental samples. CONCLUSION: Based on the results of the study, it was suggested that the complex influences of the physical and chemical properties of the polymer on its mucoadhesive properties

New Fluorescent Hybrid Materials Based on Eu-Complexes in Oxyfluoride Glass and Glass-Ceramic Matrix

Hybrid materials were synthesized using a high temperature reaction. We used 80PbF2–20B2O3 glass as an inorganic matrix and various phenanthroline complexes europium(III) – as organic phosphors. The photoluminescence spectra of hybrid materials were measured just after synthesis and after heat treatment. We suggested that an exchange reaction between a Eu-complex and a glass matrix had occurred

Event-related responses reflect chunk boundaries in natural speech

Chunking language has been proposed to be vital for comprehension enabling the extraction of meaning from a continuous stream of speech. However, neurocognitive mechanisms of chunking are poorly understood. The present study investigated neural correlates of chunk boundaries intuitively identified by listeners in natural speech drawn from linguistic corpora using magneto-and electroencephalography (MEEG). In a behavioral experiment, subjects marked chunk boundaries in the excerpts intuitively, which revealed highly consistent chunk boundary markings across the subjects. We next recorded brain activity to investigate whether chunk boundaries with high and medium agreement rates elicit distinct evoked responses compared to non-boundaries. Pauses placed at chunk boundaries elicited a closure positive shift with the sources over bilateral auditory cortices. In contrast, pauses placed within a chunk were perceived as interruptions and elicited a biphasic emitted potential with sources located in the bilateral primary and non-primary auditory areas with right-hemispheric dominance, and in the right inferior frontal cortex. Furthermore, pauses placed at stronger boundaries elicited earlier and more prominent activation over the left hemisphere suggesting that brain responses to chunk boundaries of natural speech can be modulated by the relative strength of different linguistic cues, such as syntactic structure and prosody.Peer reviewe

CLINICAL-MORPHOLOGIC AND MOLECULAR-BIOLOGIC PROGNOSTIC FACTORS FOR RARE FORMS OF UTERINE CANCER

This review of literature is devoted to rare forms of uterine cancer. Comparative characteristics of each histological type are given. Clinical-morphologic and molecular-biologic prognostic factors are analyzed in details

The clinical and morphological features of ovarian steroid cell tumors

Ovarian steroid cell tumors are rare, unusual neoplasms. There is now no unified management tactics for patients with this pathology. The paper reviews the literature on the clinical and morphological characteristics, prognostic factors, diagnosis, and treatme nt in patients with ovarian steroid cell tumors

Development of Composition and Technologies of Dental Gel of Meloxicam

BACKGROUND: Dental gels have several advantages over other oral dosage forms. Being a viscoplastic dosage form, the gel, when applied to the damaged area of the gum or mucous membrane, creates a protective film, preventing mechanical irritation, and providing a localized effect of the drug components. AIM: The aim of this work was to develop the composition and technology of the dental gel of meloxicam, the study of the main technological and consumer characteristics, as well as the local irritating effect of the dosage form. METHODS: Dental gels were prepared using purified water, alcohol, glycerol, and buckthorn oil as solvents, gelling agents used were: Hydroxyethylcellulose Natrosol® 250 HHX Pharm, Carbopol® 974P NF Polymer, and solubilizer Poloxamer 407 (Lutrol® F 127). The bioadhesive component and Noveon® Polycarbophil component were used for dental gel preparation. Aspartame was used as sweetener. Menthol and ascorbic acid were used to correct the organoleptic properties of the pharmaceutical composition. The formulated dental gel of meloxicam at a concentration of 7.5% was evaluated for organoleptic properties, pH, rheological characteristics, bioadhesive properties, and stability under the accelerated aging period. The in vivo local irritant effect was evaluated using ten rabbits by cutaneous, subcutaneous, subconjunctival administration, as well as application to the upper palate. RESULTS: Based on the results of studying technological and organoleptic properties, the optimal composition based on the Natrosol® 250 HHX hydroxyethylcellulose gelling agent, glycerol solvent, and purified water in the ratio 1/5 was selected, the composition contains Noveon® bioadhesive in an amount of 2%. The composition has good taste, pH close to pH of saliva has high bioadhesive properties, satisfactory rheological characteristics. The shelf life of the experimental series by accelerated aging was 2 years. The selected composition does not have a local irritant effect. CONCLUSION: A new dosage form of meloxicam was developed – a gel for use in dental practice

Clinical and morphological characteristics of neuroendocrine tumors of female reproductive organs

The paper deals with the clinical and epidemiological features of human neuroendocrine tumors (NET) and those of female reproductive organsin particular. It presents current approaches to classifying these neoplasms in relation to their embryogenesis and biological properties. The clinical and morphological features of NET of female genital organs are described in detail. Microscopic and immunohistochemical criteriacharacterizing NET are also given