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The results of light and electron microscopic study of the photodynamic destruction of the mouse liver with the use of Russian and imported photosensitizers (PS) at the concentration peak are presented. Considerable differences in the primary targets are noted; the changes correlated at the tissue and ultrastructural level. The use of two PS showed the damage of the soluble part of the cytoplasm: generalized cytoplasm damage with the involvement of main cell organelles in one case and the destruction of the sinusoidal lining and the hepatocyte sinusoidal pole with a diffuse spread of changes beyond the main focus of the damage close to the vascular bed in the other. Theoretical importance and practical application of the study are discussed. more...

102 myogenous tumours and 12 unchanged areas of the uterine wall were studied histologically, morphometrically, stereometrically, microspectrophotometrically and electron microscopically. The differential-diagnostic importance of the mitotic activity, nuclear DNA content, volume proportion of the myofibrillar material in comparison with the cell density and volume proportion of nuclei is shown. more...

Electron microscopical analysis of 113 cases of neurogenic tumours of the human soft tissues is presented. Ultrastructural signs of neurogenic differentiation are distinguished; neuronal and those of nerve sheaths. The comparison of the ultramorphology of neurosarcomas with that of carcinoids and granular cell tumours is performed. A considerable increase of the proportion of neurogenic tumours among soft tissue neoplasms is noted after the ultrastructural investigation. Differential diagnosis of neurosarcomas and malignant histiocytomas and other tumours at the electron microscopic level is discussed. more...

Human embryonal liposarcoma and embryonal fat have been studied histologically, in semithin sections, and electronmicroscopically. Specific ultrastructural features of embryonal liposarcomas allowing them to distinguish from other tumours are as follows: the presence of lipid vacuoles varying in size, number and structure, small mitochondria with dense matrix, specific filamentous apparatus, basal-like material in plasma cell membrane and in the intercellular space cytoplasmic sprouts forming peculiar "pockets" and general cell architectonics. Similarities and differences in the ultrastructure of embryonal liposarcomas and embryonal fat are found. more...

The dynamics of redistribution of the isoenzymatic spectrum of lactate and malate dehydrogenases in the cells of rat embryo fibroblasts (REF) having been in contact with human adenovirus type 12, as compared to the dynamics of changes in the fine structure of the cellular mitochondria of the same models was studied. The action of oncogenic virus caused rearrangment in the isoenzymatic spectra of lactate and malate dehydrogenases both in the nuclei and in the cytoplasm. These disturbances occur from the first days of the REF culture interaction with the oncogenic virus and are not connected with the proliferative growth of the cell culture, but they are stipulated by the very fact of the virus influence on the cell. Comparison of the kinetics of the changes in the enzymes under study with the data of quantitative analysis of the fine structure of the mitochondrial apparatus demonstrated that biochemical shifts occurred much earlier, practically from the moment of infecting. more...

The research was concerned with electron microscopic analysis of 34 lung tumors histologically identified as small cell lung cancer. It was shown that ultrastructural studies can reliably identify histologic pattern of small cell lung cancer. In most cases, this type of cancer was represented by one of the following histologic patterns: epidermoid, glandular or neuroendocrine, the latter being predominant. An ultrastructural classification of small cell lung cancer is not advisable until a clinico-morphological analysis has been carried out. more...

An electron-microscopic study was made of carcinoids, malignant carcinoids and small-cell lung cancer. These neoplasms are shown to represent one histogenetic group--neuroendocrine tumours (apudomas) of the lung. One can distinguish 3 main structural forms among them, i.e. epithelioid, sarcoma-like and symplastic. According to the ultrastructural criteria the neoplasms mentioned can be classified by their differentiation degree, as well, intermediately and poorly differentiated variants. This classification correlates well enough with the catamnesis of patients and may serve for prognosis of the disease. more...

The ultrastructure of 17 fibroblastic tumors in man has been studied. As a result, there was revealed a complex of features which might aid the electron-microscopic differential diagnosis of the neoplasms concerned: large cells with heavy cytoplasmatic processes; wide intercellular spaces which contain a specific fibrillar and granular fibrillar material; cellular nuclei sections show a typical irregular pattern represented in two variants. The intercellular fibrillar apparatus is specific enough with respect to the filaments structure, their aggregation and localization; also typical is the presence of an extensive system of granular endoplasmatic reticulum in cytoplasm. It is emphasized that the absence of some structures characteristic of other neoplasms: basal membrane, desmosomes, specific secretory granules etc. is of great importance for diagnosing such kind of tumors. more...

The ultrastructure of tumor cells, as compared with normal ones, was studied morphometrically. It was found that the relationship between the ergastoplasmic apparatus and polyribosomal one could serve as an objective criterion of the degree of differentiation of normal cells under study. Tumor cells did not differ from normal cells with regard to one system of organells being more highly developed than the other, but they did from the point of view of different relations between the protein-synthesizing and energetic apparatuses. Also, tumor cells were found to be less differentiated than normal, and more malignant tumors show no less differentiation than more benign ones. Tumor cells are likely to have their own trends of development that differ from the processes of normal cells differentiation. more...

Six human vascular neoplasms were studied in light and electron microscopes. Electron microscopic examinations revealed specific ultrastructural features of tumour pericytes, cells of smooth-muscle tumours and tumour endothelium. Some tumours were found to be polymorphic in their cellular composition. The electron microscopy method revealed polymorphism of the tumour with diffuse distribution of cell elements (the presence of endothelial strata in hemangiopericytoma or the presence of the pericytic component in an endothelioma) but proved to be of low effectiveness in focal distribution of cell elements. It is concluded from the foregoing that simultaneous utilization of light and electron microscopy is necessary for vertification of such complicated neoplasms as vascular tumours of man. more...

The ultrastructure of striated and smooth muscle tumors of man was studied. A set of features indicating the histological origin of these tumors was established. The most informative feature for tumors of both groups is the presence of fragments of specific microfibrillar apparatus. An analysis of the extent of its development in the cell cytoplasm showed that this feature adequately reflects the tumor cataplasia. Thus, for rhabdomyosarcomas it was considered to be expedient to distinguish three groups according to the degree of the involvement of the myofibrillar apparatus (fibrillar, filamentous, and poorly differentiated types) which may be important for the prognostic evaluation of these tumors. Similar relationships were found with smooth muscle tumors. It is concluded that electron microscopy may be used successfully for differential diagnosis and determination of the degree of cataplasia of human muscle neoplasias. more...

Histologic and ultrastructural study of basal cell epithelioma was made. It has confirmed the correctness of WHO classification according to which the mentioned neoplasms are not subdivided into different histologic forms. Comparison of basal cell epithelioma with squamous cell carcinoma and skin epidermis has shown that morphologic differentiation in this case does not correlate with clinical stage of tumour malignancy. more...

A morphometrical study of the fine structure of normal and malignant cells, both taken immediately from the organism (in vivo) or previously cultured (in vitro) was carried out. A high level on the mitochondrial morphological coefficient -- Km was discovered in normal and malignant cells in vitro. Unlike, the ergastoplasmic morphological coefficient -- Ke was high in the in vivo cells and low in the in vitro cells. The in vitro factor causes considerable changes in the fine structure of cells, which are more important than distinctions between normal and malignant cells. This fact must be taken into account in morphological studies of cells in vitro. more...

Histology and ultrastructure of human granular cell tumors (GCT) are studied. Apart from "granular" cells which are the main component of the tumor, GCT contain the cells of ordinary structure with signs of neurogenic differentiation, cell processus typical for the nervous tissue and peripheral nervous tissue tumors (these processus are in a close space connection with "granular" cells) as well as structurally transitional cells. This implies that "granular" cells are likely to originate from the ordinary lemmocytes as a result of disturbance and hypertrophy of intracellular processus. Preoperative diagnosis of this rare peculiar neurogenic tumor is difficult and the diagnosis is possible only after the operative material examination. If other signs of malignancy are lacking, infiltrative growth typical for these tumors allows one to consider them locally-destructive neoplasms. more...

The paper deals with the electron microscopic analysis of samples of 40 lung tumors histologically diagnosed as carcinoid or malignant carcinoid. The study group was shown to include tumors differing in cell ultrastructure and histological patterns. Three basic tissue patterns formed by 3 specific cellular types were identified: epithelioid, sarcomatoid and symplastic one. Tumors usually showed a combination of the said types with the predominance of one of them. Tumors exhibiting only one morphologic pattern of neurosecretory granules were much more rare. All the neoplasms studied were of neuroendocrine nature. more...

The ultrastructure of cytoplasmic filamentous material in cells of different human sarcomas was studied and several types of it are distinguished. The first type is specific and can be used as a differential diagnostic marker of tissue appurtenance of neoplasias: in fibroasarcoma cells--a uniform layer of thin filaments located near the plasmic membrane; in rhabdomyosarcomas--thick sheets of long filaments; in leiomyosarcomas--bundles of filaments with focal consolidation; in liposarcomas--loosely packed scarce layers of thin filaments of cylindrical shape; in malignant synoviomas--rod-shaped bundles of thin filaments, endotheliomas--thick single bundles of predominantly perinuclear location. Two types of nonspecific filamentous apparatus in cells of these neoplasias were distinguished: widelooped loose filamentous network and thick circular sheets. The problems of genesis and formation of filamentous apparatus of different types in tumor cells are discussed. more...

The author has studied morphometrically the cell ultrastructure of fibroblastic and smooth muscle human tumors. There were found some differences in the quantitative features of the energetic (mitochondria) and protein-synthesizing (ergastoplasm and polyribosomes) cellular apparatus of these neoplasms. The specific criteria of the malignancy grade were identified for both groups of tumors. more...

A scheme is proposed to make a morphological assessment of the tumor malignancy by separately analyzing the degree of their differentiation (as defined by tissue- or organ-specific type formation and structural manifestations of cellular specific functional activity) and that of cataplasia (as evidenced by a set of non specific signs that are largely relative to the proliferative activity of cells). The sense of the terms that denote morphological criteria for the degree of malignancy is discussed. Also, the examples that the degree of differentiation and cataplasia developed at the ultrastructural level is at variance are presented as an explanation for the fact that the clinical course and morphological signs of a tumor cannot coincide. more...

Ultrastructure of both liposarcomas of different histological types and those with non-verified diagnosis are studied. Liposarcomas are shown to contain a basic complex of ultrastructural features of lipid differentiation and different histological types of these tumours have, in principle, identical features varying in the degree of their expression. The questions of a differential diagnosis of liposarcomas and other tumours can be successfully solved on the basis of the above findings, and even more, a group of liposarcomas with a severe cataplasia that does not have histological analogues may be distinguished. The results allowed to work out an ultrastructural classification of liposarcomas in which the degree of cataplasia is directly taken into account. more...

Under examination were two gigantic-cell benign synoviomas and seven synovial sarcomas, including two metastatic tumors. The most specific ultrastructural criterion allowing a judgement of the degree of malignancy of the neoplasm under study is a parameter characterizing the predominance of ergastoplasmic protein synthesis over polyribosomal one. more...

The present study was aimed at the analysis of the ultrastructure of synovial tissue tumors and the determination of a set of signs of synovial differentiation for electron microscopic diagnosis of these neoplasias. Three benign giant cell synoviomas and 10 synovial sarcomas of different structures were studied. The results showed both benign and malignant synoviomas to have similar signs of synovial differentiation: cellular (signs of A- and B-cells of normal synovial membrane) and tissue signs (specific intercellular cavities). In benign synoviomas cellular signs are more marked, in malignant tumors tissue signs are more manifest but the detection of histioid and epithelioid components in the latter at the electron microscopic level has no principal significance. A hypothesis that A- and B-cells in synovial tumors and normal synovial membrane represent the same cellular form (synoviocyte) in different functional stages is discussed. more...