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We compared qualitative characteristics of the connective tissue at the site of implantation of polypropylene or a biodegradable polymer synthesized by electrospinning and consisting of 65% polycaprolactone and 35% polytrimethylene carbonate. Synthetic materials were implanted into the interfascial space of the muscles on the back of Wistar rats. The parameters of cellular and non-cellular structures of the forming connective tissue were studied in 1, 2, 3, 6, 9, and 12 months after implantation. It was found that the number of fibrocytes and fibroblasts around biopolymer and polypropylene increased during the period from 1 to 9 months, with a significant lag in case of biopolymer implantation; by 12 months, the number of fibrocytic cells did not significantly differ. The fibroplastic and angioplastic processes developed in the thickness of both materials, but with a one-month lag in case of biopolymer implantation due to degradation properties and nonporous structure of this polymer. Collagen fibers were actively synthesized around both materials, but in case of polypropylene, this process was more pronounced. In 6 months after implantation of polypropylene, dense regular connective tissue was formed; in 12 months after implantation of the biopolymer, the formation of dense irregular connective tissue was observed at the site of implantation. The biopolymer can be used to strengthen the core muscles.

We performed a complex morphological study of biopsy samples of prostate gland from 30 men (mean age 46±11 years) with chronic abacterial prostatitis who were exposed unfavorable anthropogenic factors. The ultrastructural heterogeneity of smooth muscle cells was shown, among which cells with destructive changes in organelles predominated, solitary cells with signs of secretory function were revealed. Most endothelial cells in microvessels were characterized by low pinocytotic activity, destruction of organelles; focal hyperplastic ultrastructural changes were noted in some endotheliocytes. Along with fibroblasts, the stroma contained single mast cells; no inflammatory infiltration was revealed. The results of the study attested to complex mechanisms of remodeling of the prostate gland stroma in chronic abacterial prostatitis involving microvessels, smooth muscle cells, and probably mast cells, which determines the development of degenerative, destructive, and fibrotic processes.

The prostatotropic activity of glycyrrhizic acid disodium salt (Na2GA) was studied in the models of benign prostatic hyperplasia (BPH) induced by chronic injection of sulpiride (40 mg/kg intraperitoneally for 8 weeks) or testosterone propionate (20 mg/kg subcutaneously for 4 weeks) in the Wistar rats. The oral administration of Na2GA in a dose of 100 mg/kg produced a moderate antiproliferative effect in both BPH models resulting in reduced volume density of prostatic epithelium (in the testosterone model) and increased volume density of the glandular lumen (in both models). The observed prostatotropic effects of Na2GA were similar to those of Permixon and finasteride, but they were less pronounced as confirmed by smaller drops in epithelial volume density and epithelial-to-stromal ratio compared to the effects of both reference drugs.

We studied the effect of a new targeted drug Pefagtal that represents a conjugate in which the MS2 phage filled with a substance toxic to cells (thallium salts) is covalently linked to peptides containing the RGD motif. The antitumor and pronounced antimetastatic effects of Pefagtal were demonstrated on transplanted mouse tumors differing in histological type and status of metastasis: Krebs-2 ascites adenocarcinoma of the mammary gland, Lewis lung adenocarcinoma, hepatoma-29, and lung adenocarcinoma. It is assumed that the RGD motif mediates primary binding of the construct to αvβ3 and αvβ5 integrins that are predominantly overexpressed in the endothelial cells of tumor blood vessels and in tumor and metastatic cells.

We compared qualitative characteristics of the connective tissue at the site of implantation of polypropylene or a biodegradable polymer synthesized by electrospinning and consisting of 65% polycaprolactone and 35% polytrimethylene carbonate. Synthetic materials were implanted into the interfascial space of the muscles on the back of Wistar rats. The parameters of cellular and non-cellular structures of the forming connective tissue were studied in 1, 2, 3, 6, 9, and 12 months after implantation. It was found that the number of fibrocytes and fibroblasts around biopolymer and polypropylene increased during the period from 1 to 9 months, with a significant lag in case of biopolymer implantation; by 12 months, the number of fibrocytic cells did not significantly differ. The fibroplastic and angioplastic processes developed in the thickness of both materials, but with a one-month lag in case of biopolymer implantation due to degradation properties and nonporous structure of this polymer. Collagen fibers were actively synthesized around both materials, but in case of polypropylene, this process was more pronounced. In 6 months after implantation of polypropylene, dense regular connective tissue was formed; in 12 months after implantation of the biopolymer, the formation of dense irregular connective tissue was observed at the site of implantation. The biopolymer can be used to strengthen the core muscles.

We performed a complex morphological study of biopsy samples of prostate gland from 30 men (mean age 46±11 years) with chronic abacterial prostatitis who were exposed unfavorable anthropogenic factors. The ultrastructural heterogeneity of smooth muscle cells was shown, among which cells with destructive changes in organelles predominated, solitary cells with signs of secretory function were revealed. Most endothelial cells in microvessels were characterized by low pinocytotic activity, destruction of organelles; focal hyperplastic ultrastructural changes were noted in some endotheliocytes. Along with fibroblasts, the stroma contained single mast cells; no inflammatory infiltration was revealed. The results of the study attested to complex mechanisms of remodeling of the prostate gland stroma in chronic abacterial prostatitis involving microvessels, smooth muscle cells, and probably mast cells, which determines the development of degenerative, destructive, and fibrotic processes.

To investigate protein content of ALK, Her2 and gene of Her2, CEP17 in interrelation with proliferative activity and survival in I-II stages lung adenocarcinoma cases. There were investigated 82 surgery samples taken from I-II stage lung adenocarcinoma patients. With the use of immunohistochemical method ALK protein (clone D5F3, Ventana), Her2 protein (clone 4B5, Ventana), topoizomerase IIα (clone JS5B4, Ventana), Ki-67 (clone MIB-1, Dako) were determined, Her2 gene was investigated with the use of the SISH method (Ventana) also. The positive expression of ALK is detected in 4(5%) cases, Her2 - in 16(20%) cases and amplification of Her2 gene - in 7(9%) cases. In lung adenocarcinoma with positive expression of ALK protein and amplification of Her2 gene low proliferative activity was noted (on labeling index Ki-67 and topoizomerase IIα). The survival of lung adenocarcinoma patients was less in cases of a positive expression of ALK protein in comparison with patients with the negative expression (difference is not reliable). Statistically significant low survival rates of patients is found in cases with amplification of Her2 gene. According to data mono- and multifactor regression analysis the amplification of Her2 gene has been interrelated with the poor forecast. Mutation of ALK gene and amplification of Her2 gene are interrelated with the proliferative activity and survival rate of lung adenocarcinoma patients.

Immunohistochemical study showed that vascular endothelial growth factor receptor-2 (KDR/Flk-1) is expressed in the cytoplasm of viable cardiomyocytes, mononuclear cells of the granulation tissue, and smooth muscle cells of intramural arteries at all terms of postinfarction reparative regeneration. Cardiomyocytes were highly heterogeneous by the intensity of staining. This feature was typical of cardiomyocytes in the ischemic area (no staining), as well as within various muscle bundles and one muscle bundle. KDR/Flk-1 expression was revealed in mononuclear cells of the necrotic area (macrophages and fibroblast cells). The distribution of KDR/Flk-1 remained practically unchanged with lengthening of the postinfarction period (more than 7 days). The increase in the heterogeneity of cardiomyocyte staining under these conditions illustrates variations in the intensity of cytoprotective processes during ischemia. KDR/Flk-1 expression in smooth muscle cells of intramural arteries was shown to increase in a later period of observations.

Study of markers of apoptosis and proliferation in relation to clinical and morphological parameters in non-small cell cancer (NSCLC) patients and healthy persons. There were investigated 237 surgery samples of NSCLC and 10 cases of normal lung tissues. p53, bcl-2, bax, Ki-67, topoisomerase IIα (ТороIIα) levels were determined by immunohistochemical method. Argyrophilic proteins associated with nucleolar organizer regions (AgNOR) were detected with silver nitrate. In NSCLC expression of p53, bcl-2, Ki-67, TopoIIα, AgNOR increased and expression of bax was lower if compared with the normal tissue. Expression of apoptotic markers (p53, bcl-2, bax) correlated with clinical and morphological parameters of NSCLC: histogenesis, N index and the stage (for bcl-2), gender (for bax). Expression of Ki-67 and TopoIIα correlated with gender, largest size of the tumor, histogenesis and differentiation. AgNOR proteins were interrelated with the gender, T and N indices, largest tumor dimension, stage, histogenesis and differentiation. In NSCLC cases the expression of apoptotic markers correlated with proliferation: in p53 positive tumors - high level of proliferation (Ki-67, TopoIIα, AgNOR), in bcl-2 positive tumors - low AgNOR, in bax positive tumors - low proliferative activity (Ki-67, TopoIIα). In NSCLC there is observed the change in expression of apoptotic markers (p53, bcl-2, bax) and proliferation (Ki-67, TopoIIα, AgNOR) in conjunction with normal tissue and clinical and morphological parameters of tumor.

Significant associations between clinical history factors, lipid metabolism parameters, and type of atherosclerotic process (area of vascular lesions and severity of clinical manifestations) were detected. The predominance of generalized atherosclerosis in chronic coronary heart disease group was associated with patients' age, more incident excessive body weight and type 2 diabetes mellitus, and more severe course of arterial hypertension. Increased lipid spectrum atherogenicity was significantly more often observed in generalized atherosclerosis in the myocardial infarction group. Angiography and postmortem examination of coronary arteries detected two trends of atherogenic remodeling of the coronary vessels: more pronounced stenosis of the main vessels in autopsy specimens from myocardial infarction patients with mainly coronary atherosclerosis and more extensive coronary bed involvement in chronic coronary heart disease patients with generalized atherosclerosis.

We performed an electron microscopic study of samples of urethral polyps obtained from 90 women (mean age 52.5±4.9 years). According to PCR and culture studies, the most common infectious agent in patients with urethral polyps is U. urealyticum (100% cases). In 70% cases, this infectious agent was present as monoinfection, of these, clinically significant concentration (>106 CFU/ml) were found in 53.3% cases. In 30% cases, associations with C. trachomatis, T. vaginalis, and M. genitalium were found. We observed significant ultrastructural heterogeneity of the epithelial cells in urethral polyps, which manifested in a combination of hyperplastic and metaplastic changes and signs of cytodestruction. Detection of mycoplasma-like bodies in connective tissue mononuclear cells and viral particles in epithelial cells during ultrastructural study, including cases with negative PCR results, indicates the pathogenetic role of latent infection in the formation of urethral polyps.

To investigate structural changes in the tumor and nontumor tissues of the prostate in patients with its cancer (PC) after treatment with high-intensity focused ultrasound (HIFU) in combination with androgen deprivation to clarify criteria for evaluating the efficiency of treatment.Comparative morphological, immunohistochemical, and morphometric analyses were carried out to examine 253 pre- and postoperative biopsy specimens, as well as transurethral resection specimens from 32 patients with localized PC and with or without a local recurrence within 3 years after a HIFU session.HIFU ablation was accompanied by coagulation necrosis and progressive pancreatic fibrosis with complete tumor regression or by a reduction in the number of positive columns (by an average of 58%) in cases with recurrence. An inverse relationship was found between the degree of a reduction in the nontumor parenchyma in the control specimens and the probability of a recurrence - a less than 20% reduction in the non-tumor glands corresponded to a 3.4-fold increased risk of tumor progression. The development of recurrence was associated with less differentiated PC (GS ≥4+3) and the presence of cribriform structures in the pretreatment samples. Combined androgen deprivation as the maximum blockade was associated with the most pronounced signs of therapeutic pathomorphism, with a reduction of the microcirculatory bed in the focus of residual tumor, and a decrease in the frequency of local progression.Neoadjuvant hormone therapy contributes to the enhanced efficiency of HIFU treatment for PC. A less than 20% reduction in nontumor parenchyma volumes in the control biopsy specimens may indicate insufficient ablation in pancreatic tissue and serve as a marker for increased risk of local progression.Цель исследования - изучить структурные изменения опухолевой и неопухолевой ткани простаты у больных раком предстательной железы (РПЖ) после лечения высокоинтенсивным фокусированным ультразвуком (ВИФУ) в сочетании с андрогенной депривацией для уточнения критериев оценки эффективности лечения. Материал и методы. Проведен сравнительный морфологический, иммуногистохимический и морфометрический анализ 253 пред- и послеоперационных биоптатов, а также образцов трансуретральной резекции ПЖ 32 пациентов с локализованной формой РПЖ и наличием или отсутствием местного рецидива в течение 3 лет после сеанса ВИФУ. Результаты. ВИФУ-абляция сопровождалась коагуляционным некрозом и прогрессирующим фиброзом ткани ПЖ с полной регрессией опухоли или уменьшением числа позитивных столбиков (в среднем на 58%) в случае рецидива. Выявлена обратная зависимость между степенью редукции неопухолевой паренхимы в контрольных образцах и вероятностью рецидива - снижение объема неопухолевых желез менее чем на 20% соответствовало увеличению риска прогрессирования в 3,4 раза. Развитие рецидива ассоциировано с менее дифференцированным РПЖ (GS ≥4+3) и наличием криброзных структур в первичном материале. Сочетанная андрогенная депривация в режиме максимальной блокады ассоциирована с наиболее выраженными признаками лечебного патоморфоза, редукцией микроциркуляторного русла в очаге резидуальной опухоли, снижением частоты местного прогрессирования. Заключение. Применение неоадъювантной гормональной терапии способствует повышению эффективности лечения РПЖ методом ВИФУ. Снижение объема неопухолевой паренхимы в контрольных биоптатах менее чем на 20% может указывать на недостаточную абляцию ткани ПЖ и служить маркером повышенного риска местного прогрессирования.

Immunohistochemical and morphometric analysis of the microcirculatory bed in the tumor and non-tumor parenchyma of the prostate was carried out with the use of endothelial cell marker CD34 in patients treated by high-intensity focused ultrasound (HIFU). The numerical density of microvessels in the adenocarcinoma focus did not correlate with the degree of its differentiation, while high values of this parameter were associated with lower incidence of local progression after HIFU. Effective HIFU ablation led to progressive fibrosis and significant reduction of the microcirculatory bed in zones of intact non-tumor glands in control samples; an inverse relationship between the degree of reduction of the microcirculatory bed and the probability of relapse was revealed. The use of HIFU in combination with androgen deprivation was associated with a decrease in numerical density of microvessels in zones of tumor and non-tumor parenchyma in patients with relapses.

Immunohistochemical analysis revealed 2.5-fold increased of expression MMP-2 in myocardium samples during the early period (up to 3 days) of postinfarction reparative regeneration. During this period, MMP-2 was detected mainly in monocytes/macrophages circulating in the blood and migrating to the necrotic zone, while expression in the intermuscular and perivascular connective tissue was lower. At later terms, with development of large focal and diffuse cardiosclerosis, MMP-2 expression significantly decreased (to the initial level) and was detected mainly in the foci of intermuscular and perivascular fibrosis, its area in the sections increased by 1.8 times. Evaluation of MMP-2 expression in the blood vessels showed that the immunohistochemical reaction was the most pronounced in the walls of new sinusoidal vessels and the minimum in the intramural arteries of medium diameter. These results attest to an important role of MMP in connective tissue remodeling (proteolytic degradation) during the early period of postinfarction reparative regeneration. The decrease in MMP-2 expression observed at later terms correlated with myocardial fibrosis progression.

Structural reorganization of the bladder mucosa in chronic cystitis and its correction by ozone therapy were studied. A relationship between the epithelial layer restructuring of different kinds (dystrophy, metaplasia, and degeneration), level of cell proliferation, and ultrastructural organization of urotheliocytes was detected. This complex of structural reactions was combined with dysregulation of tissue bloodflow in the bladder mucosa, shown by laser Doppler flowmetry. Positive structural changes were most marked in intravesical and less so in parenteral ozone therapy added to the therapeutic complex and manifested in reduction of inflammation and alteration in parallel with more intense reparative reactions. A special feature of parenteral ozone therapy was a significant improvement of microcirculation in the bladder mucosa.

Immunohistochemical and PCR analysis of the structure of lipid-containing hepatocytes and replication of chronic hepatitis C viral particles revealed no positive correlation between the presence of HCV RNA in blood specimens, number of infected hepatocytes (by expression of HCV NS3Ag) with clinical biochemical parameters and intensity of structural changes in biopsy specimens. Small-vesicular subcytolemmal lipid infiltration of hepatocytes was detected, presumably associated with hepatitis C virus replication phase. Characteristic subcytolemmal location of the lipid droplets can reflect their involvement in virus transport from the cell and indicate a virus-induced nature of lipid metabolism disorders.

Long-term vibration exposure of humans leads to development of manifest atrophy and structural mosaicism of the bronchial epithelium in the mucosa of the large bronchi (diffuse degeneration of multilamellar cylindrical epithelium, focal hyperplasia, and squamous cell metaplasia). The mucosal subepithelial stroma is characterized by sclerosis, hypoelastosis, and reduction of microvessels. Radioautography confirms the reduction of protein-producing activity of bronchial epitheliocytes and endotheliocytes.

We present results of pathomorphological study of the mucosa epithelium in various parts of the gastrointestinal tract in Crohn's disease. Particular attention was paid to structural transformation of epithelial cells. Barrier dysfunction of the gastrointestinal mucosa was shown to be one of the major pathogenetic factors for Crohn's disease.

Comparative analysis of reparative reactions in the anterior tibialis muscles of OXYS and Wistar rats after intramuscular injections of bupivacaine was carried out for eva, luating the regeneratory potential of skeletal muscles under conditions of chronic disorders of oxidative metabolism. Lumpy degradation of lesion foci and mononuclear cell infiltration predominated on day 1; after 3 days myoblast proliferation and fusion processes were maximally pronounced; after 7 days maturing myotubules created groups of fibers with central nuclei. At the ultrastructural level, regeneration of the muscle fibers was associated with signs of activation of their nuclei and of satellite cell nuclei. Lesser (in comparison with the control) mean cross-section areas of the muscle fibers on day 14 after the start of the experiment indicated that the regeneration processes were not completed by this term. The proliferative potential of myogenic precursor cells was retained in hereditary dysfunction of mitochondria in OXYS rats.

Universal types of muscle fiber injuries associated with characteristic changes in the myofibrillar system predominate in the spectrum of reactions to acute disorders of cell metabolism caused by bupivacaine. Quantitative parameters of the pathogenic exposure and structural and metabolic characteristics of the target fibers largely determine these changes: pronounced contractures involving primarily white muscle fibers, high incidence of disseminated and mixed forms, among which a special variant with predominant lytic processes (“cytolysis”) was distinguished. Minimum changes in the contractile system were often paralleled by diffuse destruction of mitochondria, which attested to the role of these organelles in the development of muscle fibers alteration in this model.

Helicobacter pylori persistence in patients with chronic gastritis is associated with a complex of nonspecific structural reactions, the type of these reactions correlates with the severity of infection: catarrhal fibrotic changes in the gastric mucosa predominate in cases with manifest colonization, while the absence of H. pylori is associated with predominance of fibrotic process. Analysis of the incidence of some pathomorphological phenomena (degeneration, atrophy, metaplasia, and dysplasia of the surface epithelium) shows no relationship between the presence of H. pylori and colonization intensity. In all patients with chronic hepatitis, the gastric mucosa is involved in the pathological process; fibrosis (gastropathy) was the most common process. No appreciable correlations between the structural changes and hepatitis activity and the presence of H. pylori were detected.

Changes in the mitochondrial compartment are the central element in the morphogenesis of musculoskeletal abnormalities in early aging OXYS rats. Compensatory hyperplasia and hypertrophy with enlargement of the working surface area are seen in these organelles at the age of 2 months. The mitochondria are characterized by polymorphism, compact packing of cristae. By the age of 9 months destructive changes and sharp reduction of the mitochondrial compartment are observed is many myocytes. Disorders in the mitochondrial structure and function and oxidative stress can be among the causes of degenerative changes in the myofibrillar system and other structures of muscle fibers, including those resultant from activation of apoptosis.

Combinations of various factors of polypogenesis determine the formation of a mixed structural phenotype of urethral polyps consisting of heterogeneous changes of the epithelium (hyperplasia, metaplasia, and erosions), inflammatory cell infiltration of the stroma, and dilatation of the venous plexus vessels. Urogenital infections are associated with the predominance of symptoms of inflammation, high serum levels of IL-1β and TNF-α, more extensive areas of inflammatory infiltration and subepithelial microvascular bed, predominance of hyperemic form of microcirculatory disorders. The combination of hyperplastic reactions of the epithelial layer with neoangiogenesis and myofibroblast proliferation in the subepithelial zone confirms the key role of dysregeneratory hyperplasia in the mechanisms of polypogenesis.

Degeneration and atrophy of the epidermis, disorganization of the connective tissue, focal atrophy of skeletal myocytes, and diffuse vasculopathy are the main pathomorphological signs found in musculocutaneous bioptates during the antiphospholipid syndrome associated with systemic lupus erythematosus. The major morphogenetic disorder is alteration of microvascular endotheliocytes accompanied by the formation of concentric perivascular mononuclear infiltrates.

We studied ultrastructural characteristics of renal cortical cells in patients with systemic lupus erythematosus. Endotheliocytes in periglomerular arterioles underwent primary and most pronounced changes. Examination of glomerulocytes revealed early alterations in endotheliocytes, compensatory proliferation of mesangial cells, overproduction of the mesangial matrix, and metaplasia of podocytes. Biosynthetic reactions reflected the structural and functional heterogeneity of endotheliocytes associated with their damages and regeneration.

The pathological picture of an acute disorder of cell metabolism caused by dimethylparaphenylenediamine consists of typical focal reactions of striated muscles to injury: myofibril contractures and intracellular myocytolysis. Analysis of the pathological process demonstrates the time course of contracture injuries as a succession of overcontracture (first-third degree contractures) and necrobiotic phases (fourth degree contracture), followed by lump degradation and macrophagal resorption. Two polar types of contractures are clearly differentiated by the size, shape and structural and metabolic characteristics of target fibers: “ribbons“ and ”medallions”. Disappearance of Z strips, disaggregation, disorientation, and fragmentation of myofibrils are typical of intracellular myocytolysis. The observed changes form the morphological basis for acute disease of striated muscles.

Acute experimental pancreatitis induced by injection of trypsin into the pancreatic tissue exhibited characteristics of fulminant hemorrhagic pancreonecrosis (intense exudation of interlobular stroma, massive plasmo- and hemorrhages, foci of acinar cell autolysis involving by the end of day 1 an appreciable portion of the organ with formation of fields of necrosis and hemorrhagic imbibition of the glandular parenchyma, virtually completely without demarcation cellular reaction). Marked microcirculatory disorders and degenerative and necrobiotic changes in the duodenal mucosa and liver reflected the polyorgan nature of the pathological process. This model of hemorrhagic pancreonecrosis corresponded to the most severe forms of this conditions observed clinically.

Peculiarities of pathomorphogenesis of two destructive forms of acute pancreatitis were compared using three experimental models. We have shown that the direction of the pathological process is determined by specific combinations of pathogenic factors. Pathological processes caused by common bile duct ligation (ductal hypertension) alone and in combination with injection of phospholipase A2 are characterized by mixed pattern with strong predominance of fat necrosis symptoms (coagulative acinar necrosis, inflammatory demarcation, and sites of lipolysis) and hemorrhagic necrosis, respectively. Trypsin injection into the pancreatic tissue induces rapidly progressing hemorrhagic pancreatic necrosis with massive hemorrhages, extensive acinar necrosis, and weak cell reaction. Considerable differences in pathomorphogenesis and outcome of the pathological process allow us to consider pancreatic fat necrosis and hemorrhagic necrosis as separate morphological and functional entities, which is essential for the prognosis and treatment strategy.

Hepatorenal cell populations were studied in patients with HCV and HBV infection markers and renal dysfunction. Pronounced mosaicism of ultrastructural changes in hepatocytes was associated with polymorphic cytopathic effects caused by RNA-genome hepatitis C virus and DNA-genome hepatitis B virus. The destructive component of the tubular compartment predominated in renal biopsy specimens from patients, with subsequent degeneration of the tubular epithelium associated with progressive interstitial fi brosis. Immunohistochemical studies detected HCV NS3Ag and HBcAg structural marker in the tubular epitheliocytes. An appreciable part of the structural and functional changes in the liver in patients with HCV and HBV infections was caused by the therapeutic complex, including programmed hemoperfusion.

Pathomorphological studies of lipid-containing hepatocytes included in the system of major markers of hepatitis C showed that the phase of hepatitis C virus replication (PCR data) corresponds to subplasmalemmal microvesicular steatosis of hepatocytes.

The data obtained in this study suggest an integrated cascade of destructive and compensatory reactions triggered by disruption of metabolic equilibrium in skeletal muscle cells. Actual parameters of the pathologic process are determined by the intensity and dynamics of the injurious stimulus rather than by its specific nature and also depend on the adaptive potential of target muscular fibers. General analysis of experimental pathologic processes differing in dynamics of injurious impacts permitted to distinguish chronic and acute variants of the development of pathologic changes and the respective spectra of structural reactions. Acute injuries (contracture and lysis) appear to roughly fall into the two categories, confined and extended. De novo restoration of complicated cell architecture being rather "expensive", limitation of damage acquires special significance. Many of the confined destructive events may be regarded as "adaptive" in respect to a higher organizational level. In chronic pathologic processes, gradual accumulation of structural and energetic disturbances leaves time for adaptive rearrangements to develop. The most prominent adaptive reactions are at first confined to mitochondrial compartment and thereafter give place to its structural decompensation. Increasing fragmentation of mitochondrial reticulum may be "preventive" in that it contributes to isolation and removal of its irreversibly damaged parts and can therefore be considered as the first ("metabolic") phase of the damage restriction strategy. Under the threat of total demolition of a skeletal muscle fiber, its "mechanical" fragmentation associated with local destruction of the contractile apparatus becomes of primary importance along with extracellular factors participating in fast removal and reparation of the damaged fragment. Insufficiency of these reactions or extreme character of the impact promotes the spread of the lesion over the entire fiber or its large part. Extended forms of damage are associated with intense infiltration by inflammatory cells and, after elimination of cell debris, produce a structural defect compensated by newly formed regenerating fibers and connective tissue expansion.

A complex of structural changes in the parenchymatous and stromal compartments, characteristic of the primary degenerative process (bronchial epithelium degeneration and subsequent diffuse atrophy, reactive sclerosis of the stroma) develops in the large bronchi in asthma. Induction of the regeneratory reactions of the bronchial epithelium with synchronously developing reorganization of the stroma (loosening of the connective tissue and stimulation of its vascularization) is shown during correction of asthma. Association of positive structural changes with lymphoid tissue hyperplasia in the bronchial wall can be interpreted in the context of significant role of lymphocytes in induction of the regeneratory reactions.

Pronounced changes in the capillaries, hemodynamic disorders, epitheliocyte degeneration and atrophy develop in the buccal mucosa of patients with types I and II diabetes mellitus in the absence of inflammatory cellular infiltration or with facultative infiltration. The morphogenesis of pathological changes can be regarded as primary diabetic microangiopathy causing metabolic disorders with the development of degenerative and atrophic changes in all structural components of the buccal mucosa and development of diabetic parodontopathy, a primary degenerative process.

We studied ultrastructural characteristics of renal cortical cells in patients with systemic lupus erythematosus. Endotheliocytes in periglomerular arterioles underwent primary and most pronounced changes. Examination of glomerulocytes revealed early alterations in endotheliocytes, compensatory proliferation of mesangial cells, overproduction of the mesangial matrix, and metaplasia of podocytes. Biosynthetic reactions reflected the structural and functional heterogeneity of endotheliocytes associated with their damages and regeneration.

Degeneration and atrophy of the epidermis, disorganization of the connective tissue, focal atrophy of skeletal myocytes, and diffuse vasculopathy are the main pathomorphological signs found in musculocutaneous bioptates during the antiphospholipid syndrome associated with systemic lupus erythematosus. The major morphogenetic disorder is alteration of microvascular endotheliocytes accompanied by the formation of concentric perivascular mononuclear infiltrates.