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PubMed1981

[Organ-specific ultrastructural cellular signs of cancerous breast tumors].

The ultrastructural analysis of 40 cases of mammary carcinomas revealed two groups of cells: with ultrastructural organ specific features (differentiated cells) and without them (undifferentiated cells). Intracytoplasmic lumens, secretory granules (lipid, protein, and mixed lipid-protein), and myoepithelial cells are the main organ specific features of mammary carcinomas. The histospecific features showing the epithelial origin of the tumor cells include cell-to-cell contacts, ductules, intercytoplasmic lumens with microvilli, and fragments of basal lamina. These ultrastructural features of mammary carcinomas can facilitate the differential diagnosis of tumors of this organ.

Adenocarcinoma↗

PubMed1982

[Ultrastructural changes in populations of the pertussis microbe exposed to antibiotics].

The ultrastructural changes in the populations of the pertussis causative agent maintained for a prolonged period of time on nutrient media containing antibiotics were studied with the method of electron microscopy. Significant changes in the ultrastructure of the cells and the population composition due to the effect of tetracycline, levomycetin or erythromycin were observed. The ultrastructure of the populations affected by penicillin or streptomycin and their biological properties were most similar to those of the initial strains. The electronogrammes revealed morphological heterogeneity of the initial and experimental cultures and changes in the subpopulation composition induced by the antibiotics.

Anti-Bacterial Agents↗

PubMed1982

[Histopathologic, ultrastructural, immunologic and virologic study of Gibert's pityriasis rosea].

A complete study of pityriasis rosea (Gibert) has been performed; this study includes: --a pathological and ultrastructural examination of the skin biopsies; --an immunological study: direct and indirect immunofluorescence (seric anti-cutaneous antibodies); --a virological investigation: ultrastructural examination of the specimens, inoculation of homogenized-skin specimens to 3 cellular cultures; --serological investigations for influenza A, B, parainfluenza 1, 2, 3, adenovirus, respiratory syncitial virus, Mycoplasma pneumoniae, ornithosis-psittacosis, Q-fever, herpes-virus, herpes-virus varicellae, cytomegalovirus, Epstein-Barr virus. All viral investigations had a negative result. Virus or virus-like particle has were not detected on the ultrastructural examinations. A viral infective agent cannot be incriminated as the cause of PRG. However, a large number of PRG patients had antibodies for the Epstein-Barr virus early antigen. The authors are carrying on with this particular investigation.

Adolescent↗

PubMed1983

[Stewart-Treves syndrome. 2 cases with an ultrastructural study].

The authors present an ultrastructural study of two cases of Stewart-Treves syndrome in elderly women. Under light microscopy, the dermal and hypodermal proliferations showed vascular features which were more clearly preceptible in the second case than in the first. Ultrastructural studies showed, in the first case, clefts containing erythrocytes and surrounded by neoplastic cells which were linked by zonulae adherentes. A rudimentary form of basal membrane was also noted, with an exterior lining of pericyte-like cells. In the second case, typical capillary vessels were bordered by endothelial cells containing a few pinocytotic vesicles and microfilaments, in contact by zonulae adherentes. The walls of these vessels consisted of a clearly defined membrane lined with pericytes, and constituting, in some areas, an anastomotic network due to the swelling of the endothelial cells. Ultrastructural study suggests an angiosarcomatous origin of these lesions. Finally, the article includes a review of the literature.

Aged↗

PubMed1984

[Ultrastructural characteristics of malignant non-Hodgkin's lymphoma in baboons].

The ultrastructure of 29 malignant non-Hodgkin's lymphomas of baboons including prolymphocytic lymphoplasmacytic, lymphoblastic, and immunoblastic malignant lymphomas is described. The ultrastructure of the cells of B-cell malignant lymphomas is characterized by a more developed strands system of rough endoplasmic reticulum in the tumor cell cytoplasm and the presence of structural abnormalities in the protein synthesis in some B-cell malignant lymphoma cells in the form of Russell's and Dutcher bodies. Analogous baboon and human tumors were shown to have a high degree of cell ultrastructure similarity. Rare forms of baboon malignant non-Hodgkin's lymphomas including a large-cell variant of T-cell lymphoblastic lymphoma with large multilobated nuclei and a variety of B-cell lymphoma with an intermediate degree of cell differentiation have been found. Malignant lymphoma of large multilobated T-cell type and lymphoma of the intermediate lymphocytic type occur rarely in human pathology too.

Animals↗

PubMed1978

Ultrastructural characteristics of human renal cell carcinoma in relation to the light microscopic grading.

Twenty-two consecutive cases of renal adenocarcinoma were graded histologically according to the nuclear structure of the tumor cells. The ultrastructural characteristics of these tumors were then evaluated and the findings were compared with the results of the nuclear grading. No ultrastructural characteristic was found which would have been specific for either Grade I, II, III or IV carcinomas. There was no ultrastructural features that could have been used as a basis for malignancy grading. The results show that electron microscopy has nothing to add to the nuclear grading system of renal adenocarcinoma and the value of this grading system is to be emphasized.

Adenocarcinoma↗

PubMed1983

Cystic fibrosis - ultrastructural and microanalytical studies.

This review summarizes the contribution of electron microscopy and X-ray microanalysis to the study of the pathogenesis and the diagnosis of cystic fibrosis (CF). Light and electron microscopical studies of the most severely affected exocrine glands of CF patients (pancreas, tracheobronchial submucosal glands) generally show dilatation of the ducts and inspissation of mucous material. The ultrastructure of the acinar cells, however, is normal. Functional abnormalities in the gland can be demonstrated by X-ray microanalysis of the secreted fluid. In the search for the basic defect in CF use is often made of cultured fibroblasts. The ultrastructure of CF fibroblasts is basically normal. X-ray microanalysis shows significantly lower Na and higher Ca levels in CF fibroblasts. Several of the biological effects of the 'CF factor(s)', supposedly present e.g. in the serum of CF patients or in CF fibroblast culture medium, can be demonstrated by electron microscopy or X-ray microanalysis. Ultrastructural and X-ray microanalytical studies of 'animal models' for CF have shown that pathological changes in exocrine glands resembling some of those seen in CF patients, can be induced by interference with the nervous regulation of exocrine secretion.

Animals↗

PubMedDate not supplied

[Outer segments of the retinal photoreceptors of vertebrates: the ultrastructure, development and renewal of the disks].

The external photoreceptor segments in the retina of vertebrates have been studied already more than 100 years; the intensity of these studies increased markedly during the recent 20 years due to the introduction of autoradiography and electron microscopy. These methods allowed to study the ultrastructure of external segments of the rods and cones in many vertebrate species, its development in ontogenesis, the renewal of external segments and the dependence of renewal on the diurnal rhythm of illumination. All these data have never been summed up and discussed. This review provides a general picture of studies of different aspects of the ultrastructure of external segments; the models of formation of the external segments' discs proposed by several authors are considered; the necessity of continuation and widening of comparative studies of the ultrastructure of external photoreceptor segments in different vertebrates is founded. The most important conclusions concern the differences between the rods and the cones during renewal of the membranes discs of external segments.

Animals↗

PubMed1978

Comparative studies on the ultrastructure of L forms obtained from S and R variants of Brucella suis 1330.

Electron-microscopic studies were carried out on S and R variants of Brucella suis 1330 and the production of L forms induced with the use of penicillin. No variations were established in the ultrastructure of the initial forms. However, essential differences were observed in the ultrastructure between the latter and the L-transformed Brucellae as well as changes that differentiated the ultrastructure of L forms obtained from S variants from that of L forms obtained from R variants. In both cases the L-transformed Brucella organisms have suffered substantial changes in their electron-microscopic structure. There was no cell wall, the cytoplasm was profoundly altered - chiefly the ribosomal apparatus, which, from a polyribosomal complex located peripherally in the cell, adjacent to the cytoplasmic membrane in the initial forms, has disintegrated into ribosomal units parts of which have often penetrated deeply in the nucleotide mass. Individual ribosomes remained connected with each other through DNA filaments, but there were equally cases in which links of such types were not present. The structure of the cytoplasmic membrane invariably showed three layers. The L forms obtained from R variants occasionally showed the presence of microtubules similar to those established with other microorganisms. Such structures were missing in the L forms obtained from S variants.

Brucella↗

PubMed1984

[How useful is the ultrastructural study of the cilia of the respiratory tract in the diagnosis of an immotile cilia syndrome?].

The immotile cilia syndrome (ICS) comprises a range of congenital defects of the ciliary apparatus most probably transmitted by autosomal recessive inheritance. Because cilia occur mainly in the respiratory and genital tract, the clinical symptoms of ICS are most commonly chronic sinusitis, bronchitis, bronchiectasis and male sterility. The syndrome can be associated with a situs inversus and is then called Kartagener's syndrome. We studied the ciliary ultrastructure in airway biopsies of 5 patients suffering from chronic upper and lower respiratory tract infections. With the single exception of one female patient with confirmed ICS diagnosis (Kartagener's syndrome) the etiology of the recurrent infections was unknown. The following ciliary defects were observed: missing dynein arms, radial spoke defects, missing nexin links, microtubular transpositions, compound cilia, supernumerary, absent, or incomplete microtubules, lack of ciliary orientation and various abnormal patterns of microtubular arrangement. In no instance did a patient show only a single anomaly; defects were always combined. Missing dynein arms, radial spoke defects and microtubular transpositions have frequently been described as lesions specific for ICS. Whenever these lesions were found simultaneously in both the respiratory and genital tracts, their genetic origin cannot be doubted. In our confirmed ICS patient the outer dynein arms were not missing but were reduced in number and length in a large number of cilia. The biopsy was, however, obtained from the heavily infected maxillary sinus and it is known that inflammation can lead to a loss of dynein arms. In the light of our investigations and of a review of the published cases of ciliary anomalies, it is concluded that none of the above defects in itself is specific for ICS. They may all occur as secondary lesions or sporadically as varieties in otherwise healthy subjects. It therefore appears questionable whether ICS can be diagnosed from the ciliary ultrastructure of a single airway biopsy. Assessment of ICS cannot be based simply on the ultrastructural demonstration of a particular ciliary defect, but necessitates additional considerations particularly regarding the origin of the biopsy, the sampling procedures and quantitation of defects. It appears necessary to investigate samples from different parts of the airways and quantitatively analyze the prominent lesions.

Abnormalities, Multiple↗

PubMed1984

Salivary gland monomorphic adenoma. Ultrastructural, immunoperoxidase, and histogenetic aspects.

Monomorphic adenoma of basal cell type is a salivary gland tumor believed to result from a proliferation of a single type of cell. However, ultrastructural and immunocytochemical investigations of 6 monomorphic adenomas (5 from parotid and 1 from intraoral minor salivary gland) indicate that there are two classes of these lesions, one composed of two types of tumor cells and the other wholly or predominantly made up of one type of cell (isomorphic). In the former group, the organization of the tumor cells closely mimicked that of normal and hyperplastic salivary gland intercalated ducts. Aggregates of tumor cells were arranged as an inner layer of luminal epithelial cells which were surrounded by an outer layer of cells that, in some cases, had ultrastructural and immunohistochemical features indicating myoepithelial cell differentiation. In some adenomas formed by two types of tumor cells, basal-lamina-lined extracellular spaces were identified ultrastructurally in relation to modified myoepithelial cells; such spaces had the same fine-structural features as those reported in pleomorphic adenoma and adenoid cystic carcinoma. Predominantly isomorphic adenomas were composed exclusively of luminal epithelial cells. These results indicate that despite the varied histologic patterns in the numerous subtypes of monomorphic adenoma, there is a central theme of differentiation and organization in this type of neoplasm which recapitulates the ductoacinar unit of normal salivary gland parenchyma.

Adenoma↗

PubMed1984

[Ultrastructural classification of tumor cells (based on the example of human squamous cell lung cancer)].

Ultrastructural classification of tumour cells of human neoplasms is suggested on the basis of ultrastructural examination of 110 lung squamous cell carcinomas. All tumour cells may be subdivided into two groups: the tumour cells of the first group show the ultrastructural organ- and (or) tissue specific features; the tumour cells of the second group do not exhibit such features. The tumour cells of the 1st group may be represented by one, two or several different types. The tumour cells of both groups, depending on the intracellular organelles development, may belong to one of the following three types: 1) rich in organelles, 2) with moderate number of organelles and 3) poor in organelles. All the tumours on the whole should be divided into three varieties: the first variety--the number of the 1st group cells dominate; the second variety--the number of cells of the 1st and the 2nd group is the same; the third variety--the 2nd group cells dominate. The structural-functional alterations of tumour cells (change of nuclei and other organelles) should be fixed in every case. The proposed classification reflects the diagnostic needs of electron microscopy.

Carcinoma, Squamous Cell↗

PubMed1983

Ultrastructure of isolated perfused proximal tubules from rabbit kidney. A comparison with proximal tubules fixed by perfusion in vivo.

This study was carried out to determine whether the ultrastructure of proximal tubules isolated and perfused in vitro was comparable to the ultrastructure of tubules fixed by perfusion in vivo. The kidneys of female white rabbits were either fixed by perfusion in vivo with glutaraldehyde (controls) or removed for dissection (experimentals) of proximal convoluted tubules and late proximal straight tubules. The isolated tubules were perfused in vitro with Krebs-Ringers bicarbonate solution for 1 hour after which the tubules were fixed with glutaraldehyde. The experimental tubules and the control tubules were processed for electron microscopy, compared qualitatively, and analyzed morphometrically to evaluate the volume densities and surface densities of different cell organelles and the cell membrane. Qualitatively, there were no differences in the appearance of cell organelles in experimental tubules and control tubules, except that cells in some experimental tubules accumulated small lipid droplets which were located close to mitochondria. Only a few quantitative changes were found, the most noteworthy being a 40% decreased surface density of the brush border in experimental proximal convoluted tubules and late proximal straight tubules. Damaged experimental tubules showed an increased number of vacuoles in the inverted microscope. In the electron microscope the vacuoles corresponded to swollen and disintegrated mitochondria and enlarged endocytic vacuoles. However, small degrees of tubular damage were not observable in the inverted microscope, as very small vacuoles could only be seen in the electron microscope. The results show that proximal tubules can be dissected and perfused in vitro for 1 hour without major ultrastructural changes. It should be emphasized that tubules showing an increased vacuolization in the inverted microscope may be damaged and, thus, not function optimally, and even if the tubules appear undamaged in the light microscope they may show signs of cellular degeneration in the electron microscope.

Animals↗

PubMed1983

Specificity and significance of hepatocellular ultrastructural changes in non-A, non-B hepatitis in chimpanzees.

324 liver biopsies from 71 chimpanzees with and without non-A, non-B (NANB) hepatitis have been examined by electron microscopy (E.M.) for hepatocellular changes reported to be associated with this disease. At least 2 types of ultrastructural cytoplasmic alterations were found in each of 23 cases of acute and 6 cases of chronic NANB hepatitis. Nuclear modifications were never seen. Similar ultrastructural alterations were found in infections derived from 9 different human blood borne NANB cases. In 9 animals which had received 5 different inocula, Pfeifer Type I, II, III and IV changes were seen; 3 of the 4 types occurred in 10 animals and 2 of the types in 5 animals. Type II and III changes were almost always seen together. All 4 types of alteration were usually found in biopsies taken near the peak of ALT elevation. Five of 6 animals in whom E.M. changes were detected in serial samples over a 1 1/2 to 4 1/2 year period had concurrent chronic ALT abnormality. Two of these 6 animals did not develop ALT abnormality until years after the original acute episode though E.M. changes were detected throughout this period. There was generally a good correlation between onset and duration of ALT abnormality and period when E.M. changes were detected. All samples from animals not exposed to NANB virus(es) were negative by E.M. Our findings indicate the ultrastructural cytoplasmic alterations to be highly specific for NANB infection. Since each of the 9 isolates produced essentially the same pattern of E.M. changes, it is likely that a single NANB hepatitis virus group accounts for most blood borne NANB hepatitis.

Alanine Transaminase↗

PubMed1984

Similarities and differences in the ultrastructure of two hormone-dependent and one independent human breast carcinoma grown in athymic nude mice: comparison with the rat DMBA-induced tumor and normal secretory mammocytes.

The human breast cancer cell lines MCF-7 (ER positive), ZR 75-1 (ER positive) and MDA-MB 231 (ER negative) form solid tumors within one week following inoculation into athymic nude mice. Tumor formation by MCF-7 and ZR 75-1 cells was dependent upon estrogen, whereas MDA-MB 231 cells formed tumors in ovariectomized mice with or without supplemental estrogen. Ultrastructural comparison of tumors formed by the three human breast carcinoma lines in athymic nude mice indicated that lactoperoxidase activity, milk protein and fat globule formation were virtually absent from all three tumors. The estrogen-dependent tumors (MCF-7, ZR 75-1), however, had more desmosomes, intermediate-sized microfilaments and collagen than the estrogen-independent tumor (MDA-MB 231). When the ultrastructure of the three human tumors was compared to the hormone-dependent, DMBA-induced rat mammary carcinoma and to the normal lactating rat mammocytes, the following observations were evident: a) the estrogen-dependent human tumors closely resembled the normal rat tissue in the distribution of desmosomes and collagen, b) the rat mammary carcinoma differed from both the estrogen-dependent and -independent human tumors, in having milk protein, milk fat globules and intense lactoperoxidase activity. The results indicate that these hormone-dependent and -independent human mammary tumors maintained in athymic nude mice differ markedly in their ultrastructure from the lactating rat mammocytes and the rat DMBA-induced mammary carcinoma.

9,10-Dimethyl-1,2-benzanthracene↗

PubMed1980

[Laparoscopic aspiration of Graafian follicle--its action on ovocyte ultrastructure (author's transl)].

The ultrastructure of human ovocytes was studied, the latter having been obtained laparoscopically following induced ovulation, using clomiphene and HCG. Optimum vacuum size for aspiration was tested on embryonated rat ova. It was found to be between 10 kPa and 30 kPa, that is between 100 and 300 mm H2O. Ultrastructural alteration was recordable neither from human nor from rat ovocytes. No change in ultrastructure was obtained either from subsequent in vitro culturing, and some of the ovocytes were embryonated with good success.

Animals↗

PubMedDate not supplied

Ultrastructural pathology of the thyroid folliculo-papillary and follicular carcinoma.

Twenty cases of thyroid carcinoma (10 follicular and 10 folliculo-papillary) were ultrastructurally studied. In the follicular carcinoma the most striking features were: microfollicular cavities with microvilli from the apical surface of the tumorous cells, intracellular microlumens, swollen mitochondria sometimes containing electrondense bodies and tightly packed filaments. In the solid sheaths light and dark cells were present. Golgi complexes were disposed in small dense cristae. The nuclei were large, round, oval or with a folded appearance. In the folliculo-papillary carcinoma were found nuclei with an irregular shape containing stage I and stage II inclusions, dilated endoplasmic sacks, closely packed, sometimes dystrophic mitochondria, dense bodies or tightly packed parallel filaments and numerous phagolysosomes. The peroxidase activity wa present as black precipitates in the nuclear envelope or around colloid droplets. The acid phosphatase activity was found as unhomogeneous precipitates inside the lysosomes. From this study it could be concluded that the follicular and folliculo-papillary carcinomas have some common ultrastructural features; the ultrastructural and cytoenzymological patterns suggest marked alteration of the synthesis, storage and secretion of thyroid hormones.

Adenocarcinoma↗

PubMed1978

[Ultrastructural characteristics of the incretory granules of the EC- and ECL-cells of the gastrointestinal tract].

At least three varieties of EC-cells differing in their density, form and fine structure can be revealed at the ultrastructural study of EC- and ECL-cells of the intestinal tract. Different forms of the incretory granules of the ECL-cells and heterogenous ultrastructural organization of their dense contents in man and animals make is possible not only to distinguish several forms of these cellular elements, but to speak of their specific peculiarities. It is not impossible that the ultrastructural peculiarities revealed in the incretory granules of the endocrine cells explain differences in the nature of histologically active substance which they produce.

Animals↗