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To date, there are a number of tasks and problem areas related to the technological preparation of plasma spraying and design of technical systems, the solution of which is most relevant in production areas. In this paper, studies of the processes occurring during plasma spraying were carried out. The analysis of the factors of plasma deposition influencing the development of computer-aided design (CAD) was carried out. In the course of research, a generalized block diagram of the CAD coating was developed. The stages of CAD formation for plasma spraying are simulated.

Wild type reovirus serotype 3 'Dearing PL strain' (T3wt) is being heavily evaluated as an oncolytic and immunotherapeutic treatment for cancers. Mutations that promote reovirus entry into tumor cells were previously reported to enhance oncolysis; herein we aimed to discover mutations that enhance the post-entry steps of reovirus infection in tumor cells. Using directed evolution, we identified that reovirus variant T3v10 M1 exhibited enhanced replication relative to T3wt on a panel of cancer cells. T3v10 M1 contains an alanine-to-valine substitution (A612V) in the core-associated μ2, which was previously found to have NTPase activities in virions and to facilitate virus factory formation by association with μNS. Paradoxically, the A612V mutation in μ2 from T3v10 M1 was discovered to impair NTPase activities and RNA synthesis, leading to five-fold higher probability of abortive infection for T3v10 M1 relative to T3wt. The A612V mutation resides in a previously uncharacterized C-terminal region that juxtaposes the template entry site of the polymerase μ2; our findings thus support an important role for this domain during virus transcription. Despite crippled onset of infection, T3v10 M1 exhibited greater accumulation of viral proteins and progeny during replication, leading to increased overall virus burst size. Both Far-Western and co-immunoprecipitation approaches corroborated that the A612V mutation in μ2 increased association with the non-structural virus protein μNS and enhances burst size. Altogether the data supports that mutations in the C-terminal loop domain of μ2 inversely regulate NTPase and RNA synthesis versus interactions with μNS, but with a net gain of replication in tumorigenic cells. SIGNIFICANCE Reovirus is a model system for understanding virus replication but also a clinically relevant virus for cancer therapy. We identified the first mutation that increases reovirus infection in tumorigenic cells by enhancing post-entry stages of reovirus replication. The mutation is in a previously uncharacterized c-terminal region of the M1-derived μ2 protein, which we demonstrated affects multiple functions of μ2; NTPase, RNA synthesis, inhibition of antiviral immune response and association with the virus replication factory-forming μNS protein. These findings promote a mechanistic understanding of viral protein functions. In the future, the benefits of μ2 mutations may be useful for enhancing reovirus potency in tumors., (Copyright © 2021 American Society for Microbiology.)

The Peutz-Jeghers syndrome is inherited condition, characterized by hamartomatous gastrointestinal polyposis and with mucocutaneous pigmentation. We have experienced a case with typical clinical features, diagnosed before complication's development. In order to prevent cancer setting it is recommended to perform aggressive screening and high-technological procedures.

Observations on one of the rare complications in children presenting malignant neoplasms of the abdominal cavity and retroperitoneal space are described. Over a 7-year period, operative treatment is undertaken in 42 children aged 3 to 15 years. In eleven of them (26.42 per cent) it is a matter of mechanical ileus. The type of bowel obstruction in the series of children under study is a follows: obturation-in three and adhesion-in five cases. The obturation involves the large intestine, and is due to pressure of a neoplastic process in advanced stage of development on the colon. Ileus due to adhesions occurs after operative removal of the neoplastic formation. The essential differences in type of intestinal obstruction in children with malignant neoformation in the abdominal region from the one in adult patients justify the report on the observations.

This is a retrospective analysis of 651 children, aged 0 to 14 years, presenting chest and abdominal injuries, treated over a 6-year period in the section of pediatric surgery of the Emergency Medicine Institute "Pirogov". The results of studies on the etiopathogenesis of chest and abdominal trauma, patterns of associated lesions and quality of prehospital aid are discussed. Experience with the application of updated noninvasive and invasive methods of diagnosis, as well as the scope of surgical approach to the variety of lesions by resorting to organ sparing and organ salvaging operative procedures are analyzed. On the basis of observations and experience gained to date, the indications for application of the prospective method of nonoperative treatment of certain organic lesions in the practice of pediatric surgery are broadened. The overall research project provides good reason to work out an algorithm of the therapeutic approach to children presenting abdominal and chest trauma.

The clinical course, diagnosis and treatment of Peutz--Jeghers's syndrome in childhood are discussed and a case reported in a eight-year-old girl. The disease presented with skin and mucosal melanin pigmentation in the mouth, frequent colic-like abdominal pain, due to chronic recurrent invaginations. On operation, the cause of the invaginations appeared to be 11 polypous formations in small intestines (8) and in the large intestines (3), which were subjected to radical operative removal. For an observation period the child had no complaints and was clinically healthy.

One of the rare surgical diseases of the organs in the abdominal cavity in children are the splenic cysts. For a period of 20 years (1968-1988) 3 children have been observed and treated at the Clinic of Pediatric Surgery in Sofia. The use of modern diagnostic methods--echography, computer axial tomography, scintigraphy and laparoscopy furnished an opportunity for precise preoperative organ localization of the disease in the patients observed by the authors. Partial resection of the spleen in this pathology with good postoperative results, performed for the first time in Bulgaria, encouraged the authors to recommend organ-preserving operation as the method of choice in nonparasitic cysts of the spleen.

A method of organ-preserving operations in children with injured spleen with the use of glue is described. The method is recommended for a wider use in child surgery.