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Biomedical subjects

T P Beketova

Publications and source records attributed to T P Beketova.

At least 19 recordsLinked to original sources
PubMed1991

[Role of sinusoidal cells in the morphogenesis of alcoholic liver cirrhosis].

49 liver biopsies in alcoholic liver damage (fibrosis, chronic persisting hepatitis, cirrhosis) are studied on semithin sections electron microscopically and morphometrically. Morphological varieties of hepatocytes and sinusoidal cells are revealed as well as some rules in their proportions. Domination of stellate reticulo-endotheliocytes with a high secretory and phagocyte activity correlates with high adaptive properties of hepatocytes and transformation of lipocytes into fibroblast-like cells without development of intralobular fibrosis. If nonactive variant of the stellate reticulo-endotheliocytes prevails, the number of damaged hepatocytes and fibroblast-like lipocytes increases, intralobular fibrosis becomes pronounced resulting in hepatocyte death. Role of sinusoidal cells in realization of alcoholic cirrhosis morphogenesis is discussed.

Biopsy↗
PubMed1990

[The morphological characteristics of hepatocyte dysplasia].

27 liver biopsies of patients with chronic hepatitis and liver cirrhosis of viral etiology were studied histologically, electron microscopically and morphometrically. Hepatocyte dysplasia is characterized by the disturbance of the liver lobule structure and alteration of the liver tissue regeneration. Dysplasia is manifested light microscopically by the three types of cells: large, "average" and small ones. Electron microscopically (EM) 4 varieties of dysplastic hepatocytes can be distinguished: (1) with developed cytoplasmic network, (2) with hyperplasia of mitochondria, (3) with underdeveloped organelles, (4) with highly atypical nuclei. There exists a correlation between the light microscopic and EM types of dysplasia: the 1st and the 2nd types are typical for the "average" cell dysplasia, the 3rd for the large cell and the 4th for the small cell dysplasia. The latter two ultrastructural varieties can be considered as manifestations of severe dysplasia. One of them is characterized by the large size of cells, the presence of two or three nuclei, nucleus-cytoplasmic ratio 0.3-0.4 and pronounced signs of atypical ultrastructural organization in the form of the underdevelopment and deformity of the cytoplasmic network and mitochondria. Another variety of dysplastic hepatocytes is represented by small basophilic cells with hyperchromic deformed nuclei, high nucleus-cytoplasmic ratio (greater than 0.4) and the signs of lowering the differentiation/underdevelopment of the granular cytoplasmic network, ribosome hyperplasia, the absence of the mature intercellular contacts.

Biopsy↗
PubMed1985

[Morphology of the liver in experimental shock].

The authors' and literature data on the liver changes at different types of shock are summarized with consideration of the role of etiology and pathogenetic factors. Three groups of similar liver alterations reflecting the severity of impairment of the reticulo-endothelial system (RES), microcirculation and parenchyma are distinguished. No clear-cut dependence between the liver morphological changes and the severity of shock is noted. At the same time the characteristic structural alterations for some forms of shock differing at their early stages by a predominance of neuro-reflectoral, hypovolemic or toxic component are revealed. A rapidly developing hydropic degeneration, the absence of the compensatory changes, signs of the RES deficiency with the progressing necrobiotic and necrotic processes in the liver are characteristic for a neuro-reflectoral shock. Endotoxic shock is associated with widespread intravascular thrombi, liver cell necrosis, combination of the destruction of reticuloendotheliocytes with the signs of their preceding activation, foci of a smooth cytoplasmic network hyperplasia of centrolobular hepatocytes; hypovolemic shock is characterized by activation of compensatory processes.

Animals↗
PubMed1985

[Granulomatous hepatitis].

The diagnosis of granulomatous hepatitis was made on the basis of granulomas observed in the liver biopsies from 64 patients. It is shown that the macrophagal granulomas are, as a rule, localized inside the lobules, do not possess the characteristic features and represent the morphological manifestations of a non-specific reactive hepatitis. At the same time macrophagal granulomas may be a stage in the formation of the epithelioid-cell granulomas. The latter reflect the long persistence of the antigen in the liver macrophages. In certain cases the epithelioid-cell granulomas acquire specific features and these allow one, when analysing the liver biopsies, to confirm or to suggest the etiology of the disease (sarcoidosis, tuberculosis). An essential help in establishing the etiology of granulomatous hepatitis comes from the repeated clinical examination of patients and repeated liver punctures.

Chronic Disease↗
PubMed1985

[Morphological bases of liver insufficiency in the early stages of the prolonged crush syndrome].

Light and electron microscopies were employed to examine liver of 45 rats and 20 dogs under 6- and 9-hour compression of soft tissues of the thigh and 2 to 7 hours after pressure was taken off. Morphology of liver microcirculatory disorders is presented, the incremental derangement of the cells of the reticuloendothelial system (RES) with the appearance of the signs of its function depletion after decompression is described. Alterations in the liver RES correlated with destructive changes in hepatocytes and their necrosis. The morphological alterations in the liver RES in the crush syndrome reflect the impairment of its barrier function. They may play a role in the impairment of liver regeneration processes and immunological homeostasis of the host.

Animals↗
PubMed1984

[Morphological diagnostic criteria of nonspecific reactive hepatitis].

The material of 100 punch liver biopsies from patients with a secondary nonspecific reactive hepatitis as a complication of chronic disease of the alimentary canal (gall bladder, pancreas, stomach and intestine) was studied. The criteria of morphological diagnostics of this hepatitis were elaborated. It is established that the morphology of the nonspecific reactive hepatitis depends on the pathogenesis and clinical course of the underlying disease. The response of liver macrophagal system is a basis of inflammatory changes.

Biopsy, Needle↗
PubMed1984

[Clinico-morphological characteristics of liver diseases associated with nonconjugated hyperbilirubinemia syndrome].

Altogether 98 puncture liver biopsies taken from patients with a syndrome of nonconjugated hyperbilirubinemia are examined in light and electron microscope. It is established that this syndrome frequently develops in inflammatory liver diseases, notably in primary (viral, alcoholic, medicinal) and secondary (nonspecific reactive) hepatitis. Both light and electron-microscopic investigation of liver puncture biopsies allows determining the type of a pathological process in the liver, to specify its etiology and to study the structural basis of bilirubin metabolic disorders in the liver. The mechanism of these metabolic disorders is complex and includes alteration of the bilirubin seizure by a sinusoidal hepatocyte pole, its conjugation and formation of ultimate metabolites.

Adolescent↗
PubMed1984

[Morphologic characteristics of disorders of liver function in myasthenia].

Clinico-morphological study of the liver was carried out in 54 patients with generalized severe myasthenia of 1 1/2-2-year duration. The functional values of the liver were studied before thymectomy and on the 1st post-operation day. Eight liver punctates were examined histologically and electron-microscopically. A picture of nonspecific reactive hepatitis whose clinical manifestations included hyperbilirubinemia, and disorder of the absorbing and excreting functions of the liver was revealed. Ultrastructural signs of cholestasis were found. The observed fibrosis of the organ was accompanied by hypertrophy and hyperplasia of lipocytes but without their manifest transformation into lipofibroblasts . Hypoplasia of hepatocytes was observed in myasthenia which may be due to their thymus-dependent inhibition. The mechanism of disturbance of pigment metabolism in the liver of patients with myasthenia is multi-component and may be associated with disorders in bile evacuation, hematotissue barrier, and probably, structural-functional incompetence of hepatocytes.

Hepatitis↗
PubMed1983

[Sinusoidal cells of the liver and their role in pathologic processes].

The review summarizes the data on morphofunctional properties and histogenesis of 4 types of sinusoidal cells of the liver: stellate reticuloendotheliocyte (SR), endotheliocyte, lipocyte and Pit-cells. It is suggested that they be considered as a single structural-functional system forming the hematotissue barrier, the connective tissue skeleton of the lobule and taking part in neurohumoral regulations of the local processes. Most attention is given to SR which are the main element of the hepatic reticuloendothelial system. The participation of SR in the pathogenesis of hepatitis, cirrhosis of the liver, and some extrahepatic diseases has been shown to be connected not only with the disturbance of their phagocytic function but also with the deficiency in formation and correction of local immune reactions as well as the entire immune system. It is assumed that uncompensated insufficiency of the hepatic reticuloendothelial system may facilitate chronization of the pathological process in the liver as well as the development of some of its complications.

Endothelium↗
PubMed1982

[Ultrastructural bases of heart failure in the early period of the prolonged crush syndrome].

Histological, electron microscopic, and physiological studies on the myocardium of rats and dogs in severe forms of compression syndrome (6-9 hours of compression and 2-4-7 hours after decompression) revealed three groups of morphological changes underlying cardiac insufficiency: (1) predominantly microcirculatory disorders with mild changes in cardiomyocytes detectable in bradycardia. Under these conditions the development of cardiac weakness may be based on both calcium overloading and reflectory weakening of the heart activity; (2) combination of microcirculatory disorders with marked hypoxic damage of the cardiomyocytes structure detectable under conditions of tachycardia may be an independent cause of the cardiac muscle weakness; (3) changes in the structures of cardiomyocytes responsible for nervous impulses conduction: sarcolemma and its derivatives. Under this condition, the probable cause of cardiac disorders may be electrolyte imbalance accompanying postcompression toxemia.

Animals↗
PubMed1980

[Liver regeneration characteristics in young rats in allyl alcohol lesion of the periportal areas].

The authors analyzed ultrastructural changes in hepatocytes of weanling rats, induced by allyl alcohol (0.03 ml/kg). The most severe lesions developed in mitochondria of the periportal field of liver lobules during the first 24 hours following alcohol administration. Early signs of the regeneration were also seen in the periportal field 24 hours after exposure. Three types of dark hepatocytes were distinguished: (1) polygonal cells with the dilated endoplasmic reticulum, increased size and number of mitochodria; (2) stellate cells with the remarkably increased rough endoplasmic reticulum showing free ribosomes and a lot of large mitochondria; (3) cells consisting of irregularly arranged rough endoplasmic reticulum and a great number of small mitochondria. Large hepatocytes containing an insignificant number of organellas were seen in the later stages of the regeneration. The data obtained warranted a suggestion that the cells described represent different phases of hepatocytic regeneration.

Alcohols↗
PubMed1975

[Functional significance of dark and light cells].

Ultrastructural-functional characteristics of dark and light cells were considered from the standpoint of tissue and organ specificity on the material of skeleton muscular fibres and the mucosa of bronchi of man, the liver and kidneys of dogs in the syndrome of prolonged compression. It was shown that these cells might have three main characteristics for the activity of the organ and reflect either the specificity of their work, or alternating activity, or the vital cycle of the cell. The ultrastructure of the dark cells testify, as a result of the specificity of their work, to their adaptation to prolonged activity connected with clearcut biosynthetic and bioenergetic processes. The work of the light cells does not require apparently considerable development of plastic processes. In the alternating activity dark cells should be considered as potentially active, whereas light cells are in the state of intensive activity. The ultrastructure heterogeneity of dark and light cells, moreover, may reflect various stages of their vital cycle.

Animals↗
PubMed1975

[Functional characteristics of light and dark cells].

Comparison of peculiarties attending the structure of mitochondria in the dark and light cells with the results of studying the respiration of condensed, intermediate and orthodoxic mitochondria showed that dark cells containing condensed mitochondria were at the state of rest or specific activity associated with a high level of bioenergetic and biosynthetic processes. Light cells with a preponderant content of intermediate mitochondria are characterized by the state of active specific activity accompanied by a high energy potential, intensified energy expenditure and a reduction of the level of biosynthetic processes. Light cells with a prevalence of orthodoxic mitochondria are characterized by a low level of energy provision and a predominance of the processes of decomposition of structures over their resynthesis.

Animals↗