RU-2861497-C1 - METHOD FOR MODELLING WOUND INFECTION IN RATS IN EXPERIMENT

RU2861497C1RU 2861497 C1RU2861497 C1RU 2861497C1RU-2861497-C1

Abstract

FIELD: experimental medicine. SUBSTANCE: invention can be used for modelling wound infection. A rat under anaesthesia is incised on the anterior wall of the sheath of the rectus abdominis muscles, forming a retromuscular bed. A 2´2 cm mesh graft infected with a suspension of staphylococcus and E. coli with a microbial load of 5´10 5 CFU/ml is placed in the bed. The graft is covered with the rectus abdominis muscles and the anterior plates of their sheaths, restoring the dissected anterior wall of the sheath of the rectus abdominis muscles, and kept for 7 days. EFFECT: method, being low-traumatic, ensures guaranteed formation of wound infection without any complex manipulations or high technical equipment. 1 cl, 2 dwg, 2 ex

Inventors

Kapralov Sergei Vladimirovich
Sopliakov Sergei Iurevich
Mikhailenko Irina Aleksandrovna
Simonova Antonina Nikolaevna
Korkotian Ara Gevorkovich
Polidanov Maksim Andreevich
Volkov Kirill Andreevich
Gavrukov Dmitrii Sergeevich
Masliakov Vladimir Vladimirovich
Kashikhin Andrei Andreevich
Tsukanova Polina Borisovna
Matytsina Arina Anatolevna
Stalnov Aleksei Andreevich

Dates

Publication Date: 20260505
Application Date: 20251114

Claims (1)

A method for modeling a wound infection in rats in an experiment, characterized by the fact that the anterior wall of the sheath of the rectus abdominis muscles is dissected in an anesthetized rat, a retromuscular bed is formed into which a mesh transplant measuring 2x2 cm, infected with a suspension of staphylococcus and E. coli with a microbial load of 5x105 CFU/ml, is placed, the transplant is covered with the rectus abdominis muscles and the anterior plates of their sheaths, restoring the dissected anterior wall of the sheath of the rectus abdominis muscles, and is kept for 7 days.

Description

Field of technology The invention relates to the field of medicine, namely to experimental medicine, and can be used in scientific research to model wound infection on laboratory animals - rats, to search for new effective methods of its treatment, as well as in the course of biomedical research on laboratory animals. State of the art The problem of correcting inflammatory processes is currently a pressing issue. Studying them is difficult because modeling any inflammatory process is complex and time-consuming compared to an acute process. The need to continue developing issues of pathogenesis, diagnostic methods and pathogenetically based therapy of wound infection is dictated by medical and social significance. A method of post-implantation mesh infection is known from the prior art (see Darouiche R.O. Device-associated infections: a macroproblem that starts with microadherence // Clinical Infectious Diseases. 2004. Vol. 39, No. 10. Pp. 1372–1374), according to which the mesh is implanted into the abdominal cavity, after which bacteria (for example, S. aureus) are introduced into the wound separately (in the form of a suspension or gel). This is used to simulate infection after implant placement. However, the uncontrolled distribution of bacteria (which, moreover, settle unevenly on the mesh) leads to variability in results, and the lack of a polymicrobial model (the method involves the introduction of a single type of bacteria, whereas in clinical practice infections are often caused by multiple strains (for example, S. aureus and E. coli)) distorts the assessment of the wound process. A method of incubating the mesh with bacteria before implantation (monoinfection) is also known, during which the mesh is incubated in a bacterial suspension (usually with S. aureus) before implantation, which ensures adhesion of microorganisms to the material (Morgenstern M. et al. A murine model of mesh infection // Journal of Surgical Research. 2016. Vol. 206, No. 1. P. 173–180). However, it should be noted that the proposed method simulates a polymicrobial infection (a combination of Gram-positive bacteria), and bacterial adhesion to the mesh depends on the incubation time and material type, resulting in heterogeneity of colonization (variation of up to 30% between samples). Furthermore, in real-world conditions, infections often develop due to a combination of pathogens, rather than a single species. Disclosure of the essence of the invention The technical problem of the claimed invention is the development of a method for modeling a wound infection by implanting a mesh transplant infected with a suspension of staphylococcus and E. coli with a microbial load of 5×10 5 CFU/ml into a laboratory animal - a rat in an experiment. The technical result consists in ensuring the reproducibility of modeling in a reduced time frame and in a more simplified form. The technical result is achieved by the fact that in the method for modeling a wound infection in rats in an experiment, according to the solution, the anterior wall of the sheath of the rectus abdominis muscles of an anesthetized rat is dissected, a retromuscular bed is formed, into which a mesh transplant measuring 2x2 cm is placed, infected with a suspension of staphylococcus and E. coli with a microbial load of 5x10 5 CFU/ml, the white line of the abdomen is restored, the transplant is covered with the rectus muscles and the anterior plates of their sheaths, and kept for 7 days. Brief list of drawings The invention is explained by drawings, where: Fig. 1 shows a table reflecting the average values of the CBC parameters on the 7th day of the experiment; Fig. 2 shows the results of the morphological study of the material in laboratory animals of the first group on the 7th day, stained with hematoxylin and eosin; Fig. 3 shows the results of the morphological study of the material in laboratory animals of the second group on the 7th day, stained with hematoxylin and eosin. The positions on the figures indicate: 1 – focal accumulations of neutrophilic leukocytes; 2 – cystic formation; 3 – change in the tinctorial properties of fibrin molecules in the walls of blood vessels. Implementation of the invention The method is carried out as follows. The studies were conducted on 20 laboratory rats of the Standard breed weighing 200±50 g. All manipulations and animal care were regulated by the local ethics committee of the Reaviz Medical University (protocol No. 12, 08.08.2025). The conditions of keeping laboratory animals in the vivarium are regulated by RD-APK 3.10.07.02-09 "Methodological recommendations for keeping laboratory animals in vivariums of research institutes and educational institutions", order of the Ministry of Health of the Russian Federation dated 01.04.2016 No. 199n "On approval of the rules of good laboratory practice", GOST 33216-2014 "Guidelines for the care and maintenance of laboratory animals. Rules for the care and maintenance of laboratory rodents and