Ultrastructural Reorganization of Endotheliocytes of Pulmonary Blood Capillaries in COVID-19.

The ultrastructural organization endotheliocytes of pulmonary blood capillaries in COVID-19 was studied on autopsy material using electron microscopy. Swelling of the cytoplasm and mitochondria with destruction of the cristae, dilation of the Golgi complex cisternae, a decrease in the volume density of the luminal and basal caveolae and free transport vesicles, an increase of the rough endoplasmic reticulum, as well as the presence of elements of coronavirus replication (reticulovesicular structures, zippered endoplasmic reticulum, electron-dense particles in the Golgi cisternae, and vacuoles with viral particles) were revealed. Further studies of the intracellular mechanisms used by the virus to replicate could help to develop antiviral drugs for the treatment of the new coronavirus infection.

Ultrastructure of Endothelial Cells of Myocardial Capillaries in Burn Septicotoxemia.

We studied ultrastructure and vesicular structures in endothelial cells of myocardial micro-vessels in burn patients. Electron microscopy revealed a significant decrease in volume density of vesicular structures in the endotheliocytes of myocardial capillaries in patients with burn septicotoxemia. The observed structural signs of endothelial dysfunction revealed in this category of patients can be a promising area for further research and for the development of methods of pathogenetic correction of myocardial disorders in the case of burn injury.

[Clinical and anatomical analysis of mortality from COVID-19 in sudden death and in those who died in health care facilities]. / Kliniko-anatomicheskii analiz letal'nosti ot COVID-19 pri skoropostizhnoi smerti i u umershikh v lechebno-profilakticheskikh uchrezhdeniyakh.

OBJECTIVE: Assessment of pathological and morphological changes in those who died from COVID-19 including persons received therapy in medical and preventive institutions (LPI) and who died suddenly from this pathology at home. The analysis data of the pathological and anatomical changes in 57 deaths from COVID-19 in hospitals and 74 forensic medical examinations where infectious pathology was established as the main cause of death are presented. For microscopy the sections were stained with hemotoxylin and eosin, OCG, immunohistochemical study with markers for CD3, CD 4, CD 20, SK-7. The mixed viral and bacterial lesions of the lungs were detected more often than pure viral infection in those who died suddenly from COVID-19 compared with people whose death occurred in medical facilities. This allows speaking about the lack of adequate antibiotic therapy out-patiently. Features of mononuclear lung infiltration in COVID-19 with a predominance of a moderately pronounced reaction of T-lymphocytes and a mild B-lymphocytic reaction indicate a decrease in immunological reactivity. Conducting clinical and anatomical analysis allows determining the features of pathogenesis and morphogenesis in each specific fatal case and informing the clinicians of health facilities (clinics and hospitals) allows the autopsy doctor (pathologist, forensic physician) to provide significant assistance in improving the quality of diagnosis and treatment of patients with this highly contagious severe viral disease.

[Morphological diagnosis of obstetric pulmonary embolism]. / Morfologicheskaya diagnostika akusherskoi tromboembolii legochnoi arterii.

Pulmonary embolism (PE) is one of the most common fatal complications in a wide variety of pathologies along the most common death causes of the population - diseases of the circulatory system and oncology. The development of PE in the postoperative and postpartum periods can also be fatal. The diagnosis of PE is very difficult and in 50-80% of cases it is not diagnosed at all. During autopsies it is important not only to diagnose PE but also to establish the source of its origin. An example of PE in a 34-year-old pregnant woman is given; the PE source was thrombosis of the right deep femoral vein facilitated by varicose veins of the lower extremities and severe preeclampsia. The presence of severe preeclampsia in a pregnant woman caused the development of venous sinus thrombosis accompanied by bilateral exophthalmos, necrosis of a pituitary gland part and progressive cerebral edema.

[The morphology of the connective tissue matrix and lymphatic bed of the external genitalia in primary massive localized lymphedema]. / Morfologiya soedinitel'notkannogo matriksa i limfaticheskogo rusla naruzhnykh polovykh organov pri pervichnoi massivnoi lokalizovannoi limfedeme.

OBJECTIVE: To identify the structural organization of connective tissue and vascular bed of the external genitalia in primary massive localized lymphedema. To analyze a clinical case of the development of massive localized lymphedema of the external genitalia concurrent with primary lymphedema of the lower limb in a patient with a normal body mass index. MATERIAL AND METHODS: The samples obtained by resection during volume reduction surgery were used to study the morphological features of the lymphatic bed and extracellular matrix of the scrotal skin and testicular dartos versus the samples without pathological changes. Biological samples were processed using standard techniques for histological, immunohistochemical and ultrastructural analyses. Lymphatic vessels were differentiated using the molecular lymphatic endothelial marker Podoplanin. RESULTS: In lymphedema, there was an increase in the thickness of all scrotal skin layers, a decrease in the volumetric lymphatic vessel density, an expansion of the interstitial spaces, and a change in the structure of collagen fibers that were homogenized, loosened, and swollen and did not form a three-dimensional network. The testicular dartos exhibited intermuscular fibrosis, expansion of the interstitial spaces, and perivascular leukocytic infiltration. CONCLUSION: Histological and immunohistochemical analyses revealed changes in the structural organization of the connective tissue matrix and lymphatic bed of the scrotal skin and testicular dartos in long-standing massive localized lymphedema. The feature of the described clinical case was the absence of signs of chronic inflammation and severe diffuse fibrosis in primary scrotal massive localized lymphedema in a patient with a normal body mass index.

Immunohistochemical Phenotypes of Stable and Unstable Occlusive Atherosclerotic Plaques in Coronary Arteries.

We performed a complex morphological analysis of atherosclerotic plaques obtained from 68 men with coronary atherosclerosis during coronary bypass surgery with endarterectomy. The expression of MMP-2 and MMP-9, collagen IV, CD31, CD34, factor VIII, and of smooth muscle cell actin was measured in the samples by morphometric and immunohistochemical methods. The expression of MMP-2 and MMP-9 as well as the intensity of neoangiogenesis estimated by the expression of CD31, CD34, and factor VIII in unstable plaques was significantly higher than in stable ones. Immunohistochemical analysis showed more intensive collagen IV expression in stable plaques. The observed differences in immunohistochemical phenotypes of stable and unstable atherosclerotic plaques reflect peculiarities of morphogenesis of atherosclerotic foci in the coronary arteries determining their further development.

[Changes of Content of Matrix Metalloproteinases and Their Tissue Expression in Various Types of Atherosclerotic Plaques].

AIM: to investigate diagnostically significant for atherosclerotic plaques (ASP) of various types parameters of activity of matrix metalloproteinases (MMP-3, MMP-7, MMP-9) in homogenates, as well as tissue expression of MMP-2, MMP-9 and collagen type IV. MATERIALS AND METHODS: We included in this study 54 men with coronary atherosclerosis without acute coronary syndrome who underwent coronary artery bypass surgery with endarterectomy. In the obtained samples we determined levels of MMP-3, MMP-7, and MMP-9 (by enzyme immunoassay), as well as tissue expression of antibodies to MMP-2, MMP-9 and collagen type IV. RESULTS: In unstable plaques we observed increased activity of MMP-7 and MMP-9, significant increase of tissue expression of MMP-2 and MMP-9, and decreased expression of type IV collagen. Of three types of unstable ASP the highest tissue expression of MMP-9 was found in plaques of lipid type compared with plaques of necrotic and inflammatory-erosive types. Expression of type IV collagen predominated in plaques of necrotic type. CONCLUSION: The data obtained allows us to speak about tissue expression of collagen as the marker of fibrous cap stability; the presence of metalloproteinases in necrotic detritus, collagen fibers, and cellular elements can characterize an ASP as unstable or being in the transitional structural state. The immunohistochemical method helps to detect structural elements that characterize instability in various types of ASP.

Association of Polymorphism in SCN5A, GJA5, and KCNN3 Gene with Sudden Cardiac Death.

We studied association of single-nucleotide SCN5A (rs1805124), GJA5 (rs35594137), and KCNN3 (rs13376333) polymorphisms and sudden cardiac death. Humans died suddenly from cardiac causes (N=379) and unrelated sex- and age-matched control subjects were genotyped. No significant intergroup differences were found in the frequency of rs1805124 and rs13376333 genotypes and alleles. In women under 50 years, enhanced risk of sudden cardiac death was associated with rs35594137 GG genotype (OR=3.6; 95%CI=1.2-10.4; p=0.022), while in older women it was associated with rs35594137 AA genotype (OR=3.0; 95%CI=2.3-3.9; p=0.041). In women under 50 years, GA rs35594137 genotype was associated with a protective effect against sudden cardiac death (OR=0.3; 95%CI=0.1-0.8; p=0.036). Thus, GJA5 gene rs35594137 polymorphism is significantly associated with sudden cardiac death in the examined group.

[The expert assessment of kidney damage morphology for the elucidation of the mechanism, intravitality, and duration of the injury]. / Ekspertnaya otsenka morfologii povrezhdenii pochki pri ustanovlenii mekhanizma, prizhiznennosti i davnosti travmy.

The objective of the present study was the expert assessment of the morphological signs of renal lesions depending on the type of deformation associated with a blunt trauma. The authors proposed the algorithm for the description of a kidney damage taking into consideration the specific morphological features associated with a blunt trauma. The pathomorphological changes in the kidney tissue under the normal hemodynamic conditions and in the case of hemorrhagic shock at different times after the injury taking into account its organ specificity make it possible to reliably predict the duration of the post-traumatic period.

Ultrastructure of Cardiomyocytes and Blood Capillary Endotheliocytes in the Myocardium under Conditions of Experimental Mechanical Injury to the Heart.

We studied ultrastructural changes in cardiomyocytes and blood capillary endotheliocytes in the ventricular myocardium in response to mechanical injury of the heart of varying severity in Wistar rats. Acute alterative changes in cardiomyocyte and endotheliocyte ultrastructure indicate impairment of the energy-producing, contractile, and protein-synthesizing functions of the cells after mechanical injury. These disorders play the key role in the development of acute contractile insufficiency of the myocardium in mechanical injury to the heart.

Morphological Characteristics of the Cartilaginous Tissue of Human Auricle in Different Age Periods.

A complex morphological study of the auricle to determine the human age was performed by evaluating the metric sizes between fixed points in each auricle with axial guidelines. The auricular elastic cartilage in different age periods was characterized by thickening of the cartilaginous plate, different mature and immature cartilage zone ratio, variations in the volume density of the intercellular substance and elastic fibers, and change in the numerical density of individual chondrocytes and isogroups. Aggrecan content in the cartilage was shown to increase in different age periods. Age-related structural changes in the auricular cartilage expand the possibilities of forensic medical examination and hold much promise for the identification of personality.

[Amniotic fluid embolism as a cause of maternal death].

This article reports the case of death of a puerperal woman resulting from amniotic fluid embolism. The diagnosis was established based on the results of the pathohistological study that revealed the presence of mucoproteides and epithelial scales in pulmonary blood vessels and capillaries.

[The expert observation of myocardial contusion in a child].

A case of the myocardial contusion associated with the closed blunt chest injury in the girl aged 1 year 7 months is presented. The autopsy revealed hemorrhage of an irregular oval shape, coloured dark-red, and confined to the region with the area of 4.0 x 3.5 cm. It penetrated throughout the entire thickness of the lower part of the left atrial myocardium and the upper and middle parts of the left ventricle. No other changes were found in the heart, nor were congenital cardiac and vascular malformations documented. The main factors playing an important role in the formation of the myocardium contusion are discussed. The authors emphasize that it is the children having the narrow chest with the pliable wall who constitute the group at the highest risk of accidents resulting in the chest injury and myocardial contusion.

[Pathomorphological characteristics of the myocardium in the heart stab wounds].

Pathomorphological characteristics of myocardium resulting from injuries to the heart are described with reference to their localization in different regions of the wound canal at different time periods after the injury. The studies were carried out with the use of light and polarized light microscopy.

[Assessment of ultrastructural changes in the contractile apparatus of cardiomyocytes after heart contusion].

Experimental simulation of heart contusion accompanied by acute insufficiency of myocardial contractility was followed by examination of myocardial tissue samples using transmission electron microscopy. Analysis of microstructural changes in cardiomyocytes revealed characteristic defects in their contractile apparatus. The results were used to substantiate mechanisms underlying acute insufficiency of myocardial contractility resulting from heart contusion.

Laser-induced fluorescence and X-ray spectral analysis of carious process in hard dental tissues.

Morphological and spectral X-ray analysis of carious and noncarious extracted teeth showed the patterns of dentin ossification in caries of different degree. Parietal ectopic ossification of the canal and cavity lumens in stages III and IV dental caries is regarded as a specific structural marker of pathological regeneration. The X-ray spectral analysis showed that the progress of carious process is paralleled by loss of mineral components. Laser-induced fluorescent study of tissues in extracted teeth showed 4 spectral bands corresponding to mineral and protein components of the tooth. The progress of carious process was associated with reduction of the fluorescence intensities of the spectral bands characteristic of dental collagen and mineral components.

[Histochemical study of the myocardium structure in the heart contusion].

The experimental modeling of heart contusion which was accompanied by ventricular fibrillation development was performed in Wistar rats, with the electrocardiographic study and subsequent histological and histochemical examination of the myocardium samples. Following heart contusion, acute circulatory disturbances, muscle fiber fragmentation, cardiomyocyte overcontraction or relaxation were detected in the myocardium. Also, the increase of total and intracellular calcium ion content in the myocardium was demonstrated. It is suggested that the mechanism of ventricular fibrillation development after heart contusion is associated with the increase of calcium concentration in both the cardiomyocytes and intercellular spaces leading to uncoordinated cardiac contractions.

[The use of a morphohistochemical method for the diagnosis of heart contusion].

This morphohistochemical study was carried out using myocardial tissue samples obtained from subjects with heart contusion. The aim of the study was to elucidate the cause of ventricular fibrillation associated with alternative myocardial insufficiency. It is concluded that changes of Ca2+ ion content in the myocardial tissue may be one of the factors contributing to the development of ventricular fibrillation.

[Organization of medical care in specialized medical aid group in the Interior Forces of the Ministry of Internal Affairs of Russia in different variants of their practice].

Medical troop of single-purpose (MTSP) and it's capabilities are examined in different variants of it's using in conditions of providing of immense antiterrorist acts. Setting tasks, opportune and corresponding operational environment, let use the MTSP all-out in 3 variants: classifying-evacuation hospital, field mobile hospital and medical batch for reinforcement Separated Medical Battalion. High effectiveness of the MTSP's activity is reached in consequence of it's reinforcement by qualified personnel from MMCH of Internal Troops of MIA, of wide using of aerotransport with medical equipment and using of reanimation brigade on the board, of uninterrupted providing by the blood and it's constituents. Locomotivity and efficiency of work were provided by the presence of modern well-equipped modules on wheels.