Spark Plasma Sintering of Boron Carbide Powder

The results presented in this article demonstrate that boron carbide ceramics of a perfect microstructure, of a high density (up to 99.8%) and microhardness (36.1 GPa) can be made from the industrial micron fraction powder thanks to spark plasma sintering, that opens prospects for wide SPS application in economical production of high-quality boron carbide ceramic products. Optimal ceramics production mode is based on B4C (technical powder), which makes the best combination of physical and mechanical properties and uniformmicrostructure. The experimentally set mode of spark-plasma sintering of highdensity B4C ceramics allows to lower the sintering temperature by 300 ∘C and to shorten the process time by 20 minutes relative to the corresponding values when traditional hot pressing. Keywords: spark - plasma sintering, boron carbide, densit

Hospital surgical clinic

The article reviews main stages of establishment and development of the Department of Hospital Surgery in different periods. We showed the role of heads and stuff of the department in the development of multipartial complex which aims at the unity of three components - to teach, to treat and to study. The first head of the department and of the clinic of hospital surgery (1921-1931) was N.A. Sinakevich. It was a period of establishment of the department, its staffing, formation of clinical site and training calendar. V.G. Shipachyov was the head of the department from 1931 to 1952. During the Great Patriotic War, the work of the department was aimed at the needs of war time related to the problems of reconstruction surgery and treatment of traumatic injuries. After the war, the work of the department was dedicated to the problems of hypothyroidism, obliterating endarteritis, gastrointestinal and urgent surgery. In 1953, Z.T. Senchillo-Yaverbaum became the head of the department. The work of the department was dedicated to gastrointestinal and pancreatic surgery, herniology, thyrophymas. Also the department included course of traumatology. In 1972, V.I. Astafiev became the head of the department. In this period, many young hopefuls started to work on the department. Also the research, treatment and educational complex was created on the base of the department, Regional Clinical Hospital and Siberian Branch of Academy of Medical Sciences USSR. While keeping the traditions of the department, V.I. Astafiev created new research and practice directions and special referral units - of cardiac, vascular, thoracic, purulent and urgent surgery, operative coloproctology, plastic surgery, diagnostic picture and X-ray surgery. Also the system of individual and collective training of surgical clerk. In 1988-1993 Y.I. Morozov was the head of the department. The new direction of the work was the development of complex treatment of purulent soft tissue involvement in patients with diabetes. From 1993, E.G. Grigoryev is the head of the department of hospital surgery and the Institute of Surgery

CHRONIC SUPPURANT PULMONARY DISEASES (LECTURE)

Lecture reviews etiology, pathogenesis, epidemiology, classification, diagnostics and treatment of chronic suppurant pulmonary diseases. Clinical examples that prove optimal tactics of diagnostics and treatment of chronic suppurant pulmonary diseases are presented

Rectal cancer (lecture)

The lecture deals with the issues of classification, etiology, diagnostics and treatment of rectal cancer

A Mouse Amidase Specific for N-terminal Asparagine: the gene, the enzyme, and their function in the N-end rule pathway

The N-end rule relates the in vivo half-life of a protein to the identity of its N-terminal residue. In both fungi and mammals, the tertiary destabilizing N-terminal residues asparagine and glutamine function through their conversion, by enzymatic deamidation, into the secondary destabilizing residues aspartate and glutamate, whose destabilizing activity requires their enzymatic conjugation to arginine, one of the primary destabilizing residues. We report the isolation and analysis of a mouse cDNA and the corresponding gene (termed Ntan1) that encode a 310-residue amidohydrolase (termed NtN-amidase) specific for N-terminal asparagine. The ~17-kilobase pair Ntan1 gene is located in the proximal region of mouse chromosome 16 and contains 10 exons ranging from 54 to 177 base pairs in length. The ~1.4-kilobase pair Ntan1 mRNA is expressed in all of the tested mouse tissues and cell lines and is down-regulated upon the conversion of myoblasts into myotubes. The Ntan1 promoter is located ~500 base pairs upstream of the Ntan1 start codon. The deduced amino acid sequence of mouse NtN-amidase is 88% identical to the sequence of its porcine counterpart, but bears no significant similarity to the sequence of the NTA1-encoded N-terminal amidohydrolase of the yeast Saccharomyces cerevisiae, which can deamidate either N-terminal asparagine or glutamine. The expression of mouse NtN-amidase in S. cerevisiae nta1Delta was used to verify that NtN-amidase retains its asparagine selectivity in vivo and can implement the asparagine-specific subset of the N-end rule. Further dissection of mouse Ntan1, including its null phenotype analysis, should illuminate the functions of the N-end rule, most of which are still unknown

Vsevolod I. Astafyev – the Man ahead of Time

The authors describe the life and activity of a famous scientist and qualified Russian surgeon, a great man with distinguished leadership ability in medicine and higher medical education, Professor Vsevolod Ivanovich Astafyev.As a student, Vsevolod I. Astafyev was keen about emergency surgery, and worked a lot in experimental laboratory. He graduated from the Kursk medical institute with honors, completing by the time his PhD thesis. However, he gave up postgraduate study and began working as a surgeon in a district hospital. After returning to the Kursk medical institute, Vsevolod I. Astafyev worked as an assistant at the hospital surgery department and successfully defended his PhD thesis. At the age of 35, he defended his doctorate thesis and competed for a post of the head of hospital surgery department at the Irkutsk medical institute. He had continued to be actively engaged in science, pedagogy and practical surgery, and organized the Siberian branch of the All-Soviet Union Scientific Center of Surgery of the USSR Academy of Medical Sciences. The branch had a clinical base with 220 beds at the Irkutsk regional hospital. Vsevolod I. Astafyev created a school of polyvalent surgeons, lecturers, and scholars.In 1987, Vsevolod Astafyev accepted an offer to become the deputy head doctor of the Republican hospital of Yakutia. Shortly after coming to Yakutsk city, he was elected a deputy of the supreme council of the Yakut Republic. On his initiative, supported by the Republic’s governance, a modern equipped medical center was built and put into operation within a short time. The so-called “sanctuary of science” still successfully works as one of the leading clinics of Russia and abroad

Experimental Modeling of General Purulent Peritonitis

General purulent peritonitis takes one of the first places in the structure of purulent complications. Despite the im provement of methods of diagnosis and treatment, mortality in postoperative purulent peritonitis remains quite high.Aim of the study: develop a reproducible model of postoperative general peritonitis to study the pathophysiological mechanisms of its development and the development of pathogenetically substantiated therapy.Materials and methods. The study was performed on 18 Wistar male rats aged 6 months, weighing 250–300 grams. Animals underwent laparotomy and modeling of postoperative general peritonitis according to the proposed method. Hospital strains of Escherichia coli BRLS 109 and Bacteroides fragilis 109 (strain ISCST1982, registered in Genbank), which we isolated from patients with acute appendicitis, with a total volume of 1.0 ml per animal, were used as infectious agents. Animals were taken out of the experiment under anesthesia with compliance with the rules of euthanasia at 1st, 3rd, 7th days after surgery. For morphological studies, samples of a fragment of the abdominal wall and cecum were taken. Bacteriological studies were performed on the 3rd, 7th day from the beginning of the experiment.Results. It was established that all animals developed peritonitis with the progression of purulent-destructive changes in the abdominal cavity and the development of adhesions, which was confirmed by the data of the morphological method of research. According to the results of bacteriological studies on the 3rd day, exudate infection was detected in all rats (in 100 % of observations). E. coli BLS were isolated in all cases at concentrations of 103–104 CFU/ml. The strain B. fragilis is inoculated in 3 animals at a concentration of 103 CFU/ml, which made 50 %. By the 7th day, only an aerobic E. coli strain of BLS was detected in peritoneal exudate at concentrations of 103 CFU/ml in the complete absence of growth of B. fragilis.Conclusion. We have developed a model of postoperative general peritonitis, which allows us to study the dynamics of the development of the inflammatory process in the abdominal cavity and, in terms of its clinical manifestations, is close to a real human disease. The reproducibility of the model is 100 %, which is confirmed by microbiological and morphological data

IMMUNOSUPPRESSION AS A COMPONENT OF MULTIPLE ORGAN DYSFUNCTION SYNDROME FOLLOWING CARDIAC SURGERY

Aim. To defne the role of myeloid-derived suppressor cells in the development of persistent multiple organ dysfunction followed cardiac surgeries with cardiopulmonary bypass.Methods. 40 patients who have undergone cardiac surgery were included in the study. Granulocyte myeloid-derived suppressor cells (G-MDSC) were defned as cells with the HLA-DR– / CD11β+ / CD15+ / CD33+ phenotype, and monocytic MDSC (M-MDSC) as cells with the HLA-DR– / CD11β+ / CD14+ / CD33+ phenotype using flow cytometry. Levels of cytokines, IL-1β, IL-6, TNF-α, and IL-10 were measured with an enzyme immunoassay. All patients were assigned to three groups: Group 1 – patients with the uncomplicated postoperative period (n = 14), Group 2 – patients with non-persistent MODS and its early resolution (n = 16), and Group 3 – patients with persistent MODS at day 7.Results. We observed an increase in M-MDSCs and G-MDSC at day 1 following cardiac surgery. The most pronounced increase was found in monocytic-myeloid derived suppressor cells, i.e. an 8-fold increase in M-MDSCs in all study groups at day 1 after surgery. The number of M-MDSCs remained high in patients with persistent MODS at day 7 after cardiac surgery. Levels of IL-6 and IL-10 increased at day 1 after surgery. IL-6 reached its peak level, signifcantly exceeding baseline levels. By day 7, blood levels of all cytokines have decreased, except IL-10 levels, which remained above the baseline in patients with persistent MODS.Conclusion. An increase in M-MDSCs and elevated serum levels of the anti-inflammatory cytokine IL-10 have been found in patients regardless of the presence or absence of the complications in the early postoperative period after cardiac surgery with cardiopulmonary bypass. Persistent MODS with the SOFA scoring > 5 scores at day 7 after cardiac surgery, is associated with an increase in M-MDSCs and elevated levels of the anti-inflammatory cytokine IL-10, related to higher rate of hospital infections, prolonged intensive care unit stay and higher mortality.Aim. To defne the role of myeloid-derived suppressor cells in the development of persistent multiple organ dysfunction followed cardiac surgeries with cardiopulmonary bypass.Methods. 40 patients who have undergone cardiac surgery were included in the study. Granulocyte myeloid-derived suppressor cells (G-MDSC) were defned as cells with the HLA-DR– / CD11β+ / CD15+ / CD33+ phenotype, and monocytic MDSC (M-MDSC) as cells with the HLA-DR– / CD11β+ / CD14+ / CD33+ phenotype using flow cytometry. Levels of cytokines, IL-1β, IL-6, TNF-α, and IL-10 were measured with an enzyme immunoassay. All patients were assigned to three groups: Group 1 – patients with the uncomplicated postoperative period (n = 14), Group 2 – patients with non-persistent MODS and its early resolution (n = 16), and Group 3 – patients with persistent MODS at day 7.Results. We observed an increase in M-MDSCs and G-MDSC at day 1 following cardiac surgery. The most pronounced increase was found in monocytic-myeloid derived suppressor cells, i.e. an 8-fold increase in M-MDSCs in all study groups at day 1 after surgery. The number of M-MDSCs remained high in patients with persistent MODS at day 7 after cardiac surgery. Levels of IL-6 and IL-10 increased at day 1 after surgery. IL-6 reached its peak level, signifcantly exceeding baseline levels. By day 7, blood levels of all cytokines have decreased, except IL-10 levels, which remained above the baseline in patients with persistent MODS.Conclusion. An increase in M-MDSCs and elevated serum levels of the anti-inflammatory cytokine IL-10 have been found in patients regardless of the presence or absence of the complications in the early postoperative period after cardiac surgery with cardiopulmonary bypass. Persistent MODS with the SOFA scoring > 5 scores at day 7 after cardiac surgery, is associated with an increase in M-MDSCs and elevated levels of the anti-inflammatory cytokine IL-10, related to higher rate of hospital infections, prolonged intensive care unit stay and higher mortality