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Objective: The physical and mechanical properties of samples printed from different materials subjected to post-processing in a clinic were evaluated., Material and Methods: Studied hardness and modulus of elasticity before and after sterilization by autoclaving. Based on the analysis of the literature and monitoring of the dental materials market, our choice fell on the most popular materials for 3D printing of surgical templates for dental implantation, such as: material 1 (FormLabs Dental SG Resin (Formlabs, USA)) and material 2 (NextDent SG (NextDent, Netherlands)). In connection with the events of recent years, we also took into the study a domestically produced polymer - material 3 (HARZLabs Yellow Clear PRO (HARZLabs, Russia))., Results: As a result of the study, it was found that in each of the groups of materials studied, the values of the elastic modulus of sterilized samples are higher than the elastic modulus of samples that have not undergone sterilization. According to GOST 31572-2012 (ISO 1567:1999 Polymeric materials for denture bases, non-sterilized samples of group 2 are considered not to have passed the test, since all three samples of the studied group have a crack resistance index of less than 1 MN/m1.5. Crack resistance index of sterilized samples of the group of materials 2 is also close to 1. Samples of group 1 (both sterilized and non-sterilized) have the highest crack resistance. This group also has the highest flexural strength. On non-sterilized samples of material 1, there was no crack initiation along the cut and groove. The samples of other groups were mainly destroyed along the axis of the groove., Conclusion: Analyzing the obtained data and considering that all studies carried out were in accordance with dental standards, the researchers concluded that the increase in flexural strength after sterilization by autoclaving and the feasibility of using material 1 for the production of surgical templates in accordance with all manufacturer's recommendations.

With the assistance and direct participation of the Presidium of the Russian Academy of Medical Sciences, the I. M. Sechenov Moscow Medical Academy has developed and introduced an unique elitist educational system to train of scientific and pedagogical staff at the pre- and postdiploma training stages on the basis of their close relationships and continuity, within whose framework a specially designed faculty has been successfully operating for 10 years. The basic principle that ensures its effective activity and solution of many didactic problems is the individualization and differentiation of an educational process by using a great diversity of reserves and organizational forms. The created system is unique in Russian and foreign practice. It improves the quality of scientific and pedagogical staff training, promotes more effective creation of staff reserves for the departments of higher educational establishments and research institutes of the Russian Academy of Medical Sciences and the Ministry of Health of the Russian Federation.

The problems of terminology are discussed, as well as classification and definition of sepsis. Comparative analysis of traditional for our country and up-to-date foreign classifications is carried out. The criteria for diagnosis of sepsis are discussed. On the basis of 20-year experience in examination and treatment of patients with sepsis, the authors set forth their own stand, suggesting two varieties of sepsis for consideration: common complication of surgical infection, a rare disease.

Recognition of general pathology as an independent discipline is urgent at this stage of medical science development. Its contents are basic rules of the origin, development and outcomes of human diseases. It is desirable to organize in the medical schools chairs (courses) of general pathology as an supradiscipline subject the knowledge of which is necessary to the wide circle of students, interns, physicians of all specialties.

Certain biological and biochemical differences are found after biochemical and electron-microscopic examinations between different substrains of staphylococcus and Pseudomonas aeruginosa. The conclusion is made that in the development, course and form of septic process the important role is played not only by the type of infectious agent, but by its various substrains as well.

Combination of severe purulent processes (peritonitis, phlegmons, and extensive wounds of the abdominal wall), eventration, and complete high unformed intestinal fistulas leads to rapid hemostasis disorders and emaciation. In nonoperative treatment lethality reaches 70%. Complete bilateral disconnection of the fistula bearing intestinal loop is the operation of choice in such situations. In this case the length of the disconnected intestinal segments may be two thirds of the length of the jejunum and the greater part of the colon. The results of morphofunctional study of an intestinal segment disconnected for a long period are analysed. The tactics of active surgical treatment is illustrated by clinical cases.

74 patients with GSU are studied. These ulcers occur more frequently than ordinary ulcers in aged persons against the background of various diseases. "True" GSU are localized mainly in the proximal regions. GSU combined with duodenal ulcers have a course with grave complications requiring urgent surgery. GSU located in the central parts are characterized by chronic ulcer symptoms, and those located at the periphery by the symptoms of acute ulcers (centrifugal progression). Confluence of adjacent ulcers occurs at the centripetal progression. Epithelization is lacking at the edges of the majority of GSU this indicating the predominance of the destructive processes.

To close extensive infected wounds and to replace long bone defects, along with other methods a method of graded tissue strain (GTS) has been developed and introduced into practice (246 patients). The method differs from all others in that it requires no transfer of elaborate flaps while replacing soft tissue defects; and no graft or foreign body is introduced externally into the wound in replacing long bone defect. Soft tissue defect is gradually replaced by wound-adjacent intrinsic tissues, the wound is closed by related skin and bone defect is filled by an osseous regenerate which is formed during graded transposition of the osteotomized fragment. At the same time good blood supply and tissue innervation retain, which contributes to their resistance to purulent infection. The analysis of the findings has led to the conclusion that GTS is an indispensible contribution to the development of plastic purulent surgery allowing the anatomic and functional integrity of the diseased segment to be restored.

Two-wavelength scanning DNA cytophotometry was used for DNA and protein estimation in human ventricular myocytes. In many hypertrophic hearts weighing more than 500 g the DNA content assessed by ploidy of myocytes, was within the range of normal adult variation (4-10c, where c is the haploid DNA content). A correlation was found between the protein content of myocytes and the weight of the hypertrophic ventricle. In congenital heart disease, the excessive polyploidy (up to 15-20c) developed through the normal route of myocyte polyploidization in childhood. Excessive polyploidization was revealed only in overloaded hypertrophied ventricles. A correlation was identified between the ploidy level, the ventricular weight and age of the child. Excessive polyploidy was also detected in adults with congenital or acquired in childhood diseases. There was no correlation between the myocyte ploidy and age. We propose that childhood polyploidy excess persists in these adults. The ranges of polyploidy are compared with the recent data on genome: protein ratio in cardiac myocytes and the interrelationships allow us to discuss the significance of childhood heart polyploidy as a reserve utilised under pathological conditions in adults.

The paper considers the current trends in the development of biological and medical sciences: their subject, tasks, methods, and place of General Human Pathology among other subjects, its value for the clinical discipline. It defines and analyzes the most topical and disputable directions of General Human Pathology, primarily including those which form the bases for the pathology theory. Arguments are advanced for the necessity of introducing the subject General Pathology of Man into the curriculum of higher medical educational establishments at various faculties. Consideration is given to the specific features of this subject teaching at the faculty training researchers and research pedagogical personnel, at the Pharmaceutical and Higher Nurse Training Faculties of the I. M. Sechenov Moscow Medical Academy. A proposal is given to consider and to discuss the most important problems of General Pathology and its teaching, which are listed in the paper.

The article deals with the results of using cultivated allofibroblasts in topical treatment of burn wounds. Allofibroblasts obtained from the derma of burnt individuals were transplanted to the burn wounds of 28 patients. In 12 among 15 patients (80%) with IIIa-IIIb degree burns transplantation induced epithelialization of the burns in 12.1 +/- 2.4 days. Thirteen patients had deep burns, only in 3 of them with a circumscribed burn area transplantation proved effective. Complications of transplantation were encountered in 5 patients--rejection of the transplant in 2 and its suppuration in 3 patients. Allofibroblast transplantation may be applied as an independent method of treatment in IIIa, b degree burns.

The authors develop the theory of structural bases of nervous and mental activity by evidencing them with clinical notes. They stress the role of compensatory processes retarding the development of a clinical picture. Structural analysis provides strong evidence for neurology and psychiatry approaching each other and integrating into the common research subject.

The authors discuss the first results of the use of cultivated human allofibroblasts in the treatment of persisting wounds of the donor areas in 13 patients with deep burns and cicatricial deformities caused by the burns. Transplantation of cell cultures led to complete epithelialization of the wounds in 6-10 days. Complication, suppuration of the grafted material, was recorded in one case. Reaction of graft rejection was not encountered. The authors believe that the effect of the transplantation is due to stimulation of the epithelialization processes by the cultivated fibroblasts.

The work discusses the results of experience of long-year's standing of the staff of the Vishnevsky Institute of Surgery in the creation of a biological bandage with the use of cultivated human skin cells. A graft of cultivated human allofibroblasts was used for closure of burn wounds for the first time. Its efficacy was studied in 86 cases of burns. The use of cultivated allofibroblasts is indicated in bordering III ab degree burns and sluggishly healing donor areas formed after autodermoplasty. Study of the efficacy of cultivated allofibroblasts in the treatment of deep burns in combination with dermoplasty with a 1:6 perforated skin autograft are continued. The low cost and technical simplicity of the method allow cultivated fibroblast grafts to be recommended for wide clinical practice.

Morphological & computerized tomography analysis of tibial reparative regeneration in distraction osteosynthesis was performed in 12 & 25 patients consequently. The authors discuss the correlation between the two kinds of the data & show that development of bone regeneration with restoration of anatomical form & structure of the reconstructing tubular bone occurs in the place of osteotomy.

Two-wavelength scanning cytophotometry was performed for the measurement of DNA (Feulgen reaction) and total protein content (naphthol yellow S staining) in the same cardiac myocyte. A lack of proportionality between the DNA content (i.e, cell ploidy) and protein content has been detected in ventricles of normal weight in the human heart. While the ploidy classes contained ratios of 2:4:8:16:32, the ratio of the protein content was about 2:3:5:8:17. In hypertrophic left or right ventricles, the latter ratio composed a series of doubling. Owing to this additional growth, weight of muscle tissue may be increased from 30% to twice, depending on the myocyte ploidy of a given myocardium which varies from 4 to 10c on average under normal circumstances and to 30c in some cases of hypertrophy (where c is the haploid DNA content, and, accordingly, a haploid chromosome set). Thus, one of the mechanisms of cardiac hypertrophy has been revealed which comprises the first step of the growth and often the process per se. Polyploidization of cardiac myocytes and their postmitotic growth enhance the heart weight in normal circumstances and creates a growth reserve for hypertrophy under conditions of pathology in future.

Considerable change has occurred to nosology due to the advent of electron microscopy and its use in investigations of pathological processes. These investigations have shown that morphological alterations under the impact of pathogenic factors may persist for extended periods of time without any clinical manifestation due to soon effectiveness of mechanisms of compensation in the form of regeneration and hyperplasia of cells and intracellular ultrastructures (intracellular regeneration). Clinical symptoms will not grow manifest until regeneration and hyperplasia are not capable any more of compensation for tissue lesions that have resulted from dystrophy and necrosis. This is likely to offer an explanation for delay of treatment, when a patient will not see a physician until the disease has become incurable. It is the established purpose of early diagnosis to detect structural alterations in organs during the asymptomatic preclinical period, that is before the disease has reached an advanced stage. The idea of "primary existent functional and secondarily added morphological alterations" is just as erroneous as that of the existence of "purely functional diseases". Such outdated concepts used to be based on underestimation of compensatory reactions of the organism and the enormous role played by them in the development and outcome of pathological processes.

DNA cytophotometry has been performed in ventricular cardiomyocytes of hypertrophic human hearts. In the cases of hypertrophy in adults (generalized atherosclerosis, postinfarct scars), polyploidy expression did not exceed the limits of normal variability developed during childhood. In the cases of hypertrophy caused by congenital heart defects, high polyploidy has been revealed (the mean level 20c and more, where c is haploid DNA content), which considerably exceeded the upper limit of normal variability (approximately 10c). Our hypothesis has confirmed that heart hypertrophy in adults proceeds in conditions of stable genome rather than due to redundant polyploidization of the ventricular myocytes. The same idea assumes enhanced polyploidization of the myocytes in childhood in humans with congenital heart diseases.

New quality in the nature, according to the author, may appear not only in the process of quantitative changes, but by means of various recombinations (regrouping) of elements composing the system without changing their number. The variants of such regrouping are discussed. Recombinant (conformative) changes which are widely spread in the nature, play an important role in the host adaptive reactions.

A clinicomorphological analysis was performed of the gastric antrum mucous membrane of 60 patients after selective proximal vagotomy because of stenosing duodenal ulcer. The patients were subdivided into two randomized groups depending on the type of the draining operation. The first group had a gastroduodenoanastomosis for the gastric drainage and the second group underwent duodenum plasty (drainage of the duodenum). Discontinuation of the pylorus function in the gastric drainage operation resulted in higher incidence and intensity of duodenum-gastric reflux and made more severe antrum gastritis; reflux-gastritis developed frequently. Morphological signs of reflux-gastritis in 95% of cases coincided with the results of the radionuclide method. Duodeno-gastric reflux decreased as a rule Helicobacter pylori (HP) contamination of the mucous membrane but did not eliminate it completely in all cases. The combination of these two factors resulted in more severe gastritis than that provoked by each of them separately. The etiology of gastritis and its intensity may be determined only by morphological examination of gastric mucous membrane. The results of endoscopic and histologic methods coincided in 70% of cases. Duodenal-gastric reflux, HP and high acid production play a certain role in ulcer recurrence.

It is established by electron microscopical radioautography that sepsis results in the lowering of neutrophils bacterial capacity while their absorptive capacity is retained. Living bacteria may be released from neutrophils undergoing degradation into the environment. The same is observed when phagocytized but still living bacteria are located in phagosomes which are fused with one another and with neutrophil plasma membrane; after the destruction of the latter bacteria are released into the extracellular space. This is a negative issue for the host of the incomplete phagocytosis. Neutrophils participate more actively in the lysis of the necrotic tissues and wound cleaning than in the bacteria phagocytosis.

In natural phenomena a new quality may occur not only in the course of qualitative changes but also by means of different recombinations (regroupings) of the elements that constitute a system, without any change in their number. Different versions of such regroupings are discussed. Recombination (conformation) changes, widely spread in live nature in particular, are of paramount importance, playing a role in the realization of a wide range of adaptation reactions of the body.

With general atherosclerosis, the ploidy of left ventricle myocytes in the hearts of patients that underwent infarction corresponds to the norm variation irrespective of the ventricle and heart weights. At heart diseases the myocyte nucleus ploidy is often much higher than the norm variability both in hypertrophied ventricles and in those with normal weight. An additional polyploidization is suggested that may occur at some natural ontogenetic periods of human development (in the childhood) during heart diseases both innate or spontaneously appearing at the particular time. Unlike, the myocardial hypertrophy in adults does not stimulate myocyte polyploidy.

Method of study of bacterial agglutination by means of serum taken from patients with wound infections was suggested. It was found out that agglutination suppresses viability of microbial cells in the center of agglutinate and reduces the risk of bacterial spreading from the wound over the body.

An autoplasty method for treatment of burns was worked out by the authors. In lab conditions a monolayer of epithelium is grown out from a piece of owner skin. Its size is 10 times (and more) as big as the initial material. The article deals with the results of treatment of 12 patients who had the transplantation of monolayer epithelium. Indications and contraindications are enclosed. The article concludes by the appreciation of data which were obtained during this work.

Lack of proportionality between DNA and protein content has been revealed in the human cardiac myocytes. The proportion 2:4:8:16 was observed in DNA of di-, tetra-, octa- and hexadeca myocytes while the protein content of the same cells was 2:3.5:5.2:7.2 in the inner layer, 2:3.5:6.5:8.9 in the central layer and 2:3.1:5.6:9.1 in the outer layer of the normal left ventricle. The protein content of myocytes of the same ploidy was higher in the inner layer than in other ones.