Surfaces of implanted medical devices are highly susceptible to biofilm formation. Bacteria in biofilms are embedded in a self-produced extracellular matrix that inhibits the penetration of antibiotics and significantly contributes to the mechanical stability of the colonizing community which leads to an increase in morbidity and mortality rate in clinical settings. Therefore, new antibiofilm approaches and substances are urgently needed. In this paper, we test the efficacy of a broad-range recombinant endolysin of the coliphage LysECD7 against forming and mature biofilms. We used a strong biofilm producer—Klebsiella pneumoniae Ts 141-14 clinical isolate. In vitro investigation of the antibacterial activity was performed using the standard biofilm assay in microtiter plates. We optimized the implantable diffusion chamber approach in order to reach strong biofilm formation in vivo avoiding severe consequences of the pathogen for the animals and to obtain a well-reproducible model of implant-associated infection. Endolysin LysECD7 significantly reduced the biofilm formation and was capable of degrading the preformed biofilm in vitro. The animal trials on the preformed biofilms confirmed these results. Overall, our results show that LysECD7 is a promising substance against clinically relevant biofilms.

Healthcare-associated infections (HAIs) are a global medical and socioeconomic problem. Nosocomial infections occupy one of the leading places among the causes of death in the Russian Federation. About 60–70% of all nosocomial infections are associated with the use of medical implants of various profiles. Pseudomonas aeruginosa, various types of streptococci, staphylococci, Escherichia coli, enterococci (Enterococcus faecalis), Klebsiella pneumoniae, Proteus mirabilis, and representatives of the genus Acinetobacter are highly  likely to be found  in biofilms of medical supplies. A distinctive feature of microbes that cause  HAIs is poly- or even  pan-resistance of microbes to recommended antimicrobials. The search  for methods and means to overcome is a priority task of modern medicine. Phage therapy seems to be one of the logical and promising ways to combat bacteria that are resistant to conventional therapy. The article outlines the advantages and disadvantages of phage therapy, provides an overview of the successful use of mono- and combined preparations of bacteriophages in the experiment and clinic, as well as modern directions for the use of bacteriophages not only for therapeutic, but also for prophylactic purposes, based on the latest achievements of genetic engineering and biotechnology.

Relevance of the current study is determined by the importance of forming proper representation of temporal relations in the use of adverbs by preschoolers with speech disorders in the course of their cognition and speech development to prepare them for formal schooling. It has been found that 6–7-year-olds with speech disorders rarely reach a sufficient level of acquiring the vocabulary of temporal relations, which is often very poor. The level of the vocabulary of temporal relations doesn’t always correlate with the structure of speech defect. The author gives differentiated recommendations for specialists to help verbalize temporal relations in the use of adverbs by 6-7- year-olds with speech disorders. The article will be of use for preschool psychologists, speech and language pathologists, preschool teachers, and other educators.

The article presents the results of a psychodiagnostic study of the socio-psychological adaptation of foreign students at medical schools in the Southern Federal District. Socio-psychological adaptation is a dynamic aspect of involving an individual's personality in a system of socially significant relationships, socio-psychological and professional-activity communications, in the implementation of the corresponding role functions. It has been established that medical students are exposed to many risk factors that violate the harmonious process of socio-psychological adaptation. Among the leading factors, the following are distinguished: the study of one of the most complex languages – Russian; differences in the cultural, communicative and linguistic characteristics of foreign students and residents of Russia; the risk of early emotional burnout during the acquisition of practical skills and intensive on the duration of classes in junior courses in a pandemic of new coronavirus infection. The study revealed that students in both samples have a normative level of socio-psychological adaptation, despite studying in different regions and in different languages (Volgograd State Medical University students study in English, ASMU students in French and Russian as a foreign language). At the same time, it was established that the most preferred strategies for behaviour in stressful situations in both groups are distance, positive reassessment, flight-avoidance and confrontation. The authors presented a statistical analysis of the data, which indicates that there are no statistically significant differences in the socio-psychological adaptation between the two samples for any of the tests performed. The results of this study can be used by the teaching staff, focused on the adaptation support of foreign students in medical universities, tutors and teachers of biomedical orientation for motivational and correctional activities of the pedagogical process. Also, these results will be useful for individual psychological correction of respondents with high maladaptation rates, low sociability indicators, and those who have problems with self-assessment of their capabilities.