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PubMed1978

Ultrastructure of intestinal cells of Heterakis gallinarum.

Ultrastructure of intestinal cells of Heterakis gallinarum is described and compared with that of Ascaridia galli from ecomorphological point of view. The great analogy in bionomy and ecology of both worms is reflected in the great analogy of ultrastructural construction. A new organoid in the intestinal cells of H. gallinarum, hitherto unknown among nematodes, is also described. It is of a vacuole-like shape running in stripes close under the terminal bar. The paper is also meant to be a supplement to the authors' previous paper (1975) dealing with ultrastructure of muscle cells of Heterakis gallinarum.

Animals↗
PubMed1981

Ultrastructural alterations in human lymphoblastoid B cell lines treated with tunicamycin.

The ultrastructure of three human lymphoblastoid B cell lines, Raji, RPMI 4098, and WIL-2, was analyzed after the cells were incubated with tunicamycin, and antibiotic that selectively inhibits N-linked glycosylation of macromolecules. After a 24-hour exposure to 1.0 microgram/ml of tunicamycin, the lymphocytes lose their microvilli and become smooth spheres or develop a few blebs. Also, the cells show a dilation of the endoplasmic reticulum and an increase in myelin figures resulting from intracellular membrane accumulation, possibly lysosomal in origin. These ultrastructural alterations are similar to those observed in Tay-Sachs, Fabrey's, and Gaucher's diseases, Type II pneumocytes in viral pneumonitis, certain lysosomal storage diseases, and in aging fibroblasts. Therefore, tunicamycin-treated cells may be a useful model in the correlation of altered ultrastructural pattern in membrane flow with the etiology of certain diseases.

B-Lymphocytes↗
PubMed1981

[Ultrastructure of malignant non-Hodgkin lymphomas].

Ultrastructural characteristic features of non-Hodgkin malignant lymphomas-based on the analysis of 51 cases are dealt with. It is concluded, that ultrastructural changes of lymphomas can be correlated with the light microscopic findings and tumours arising from T and B cells can be distinguished also on the ultrastructural level. Electron microscopy should be regarded as an additional method in classification and differential diagnosis of non-Hodgkin malignant lymphomas. It contributes to a more exact diagnosis and clarifying the histogenesis of these tumours.

B-Lymphocytes↗
PubMed1981

[Ultrastructural changes in central nervous system cells due to arboviruses].

The paper systematizes the data of the literature on ultrastructural changes in the central nervous system (CNS) of experimental animals infected with arboviruses of the Togaviridae family. The main site of virus reproduction in the CNS was found to be nerve cells in which the ultrastructural lesions typical for this group of viruses developed. The main features of these lesions consist in degeneration of rough membranes, ribosomes, and polysomes of the cell, hyperplasia and hypertrophy of smooth membranes, formation of various vacuoles and vesicles in the cell hyaloplasm. Mature virions accumulate in cisterns and cavities of the endoplasmic reticulum, lamellar complex, in vacuoles and vesicles. Each of arboviruses produces in the cells not strictly specific but typical ultrastructural lesions. In the CNS the viruses spread hematogenically, in intercellular and perivascular spaces and dendrites of the nerve cells.

Animals↗
PubMed1982

[Epidermolysis bullosa acquisita (EBA). Morphological, immunocytochemical, optical and ultrastructural study about one case (author's transl)].

Epidermolysis bullosa acquisita (EBA) is a rare non hereditary bullous disease. One case is described with a morphological, and immunocytochemical ultrastructural study. The plain ultrastructural morphology showed a dense amorphous deposit in the superficial dermis, under the basal lamina. Immunofluorescence showed IgG and C3 deposits. The ultrastructural study (direct immunoperoxidase technique using Fab) showed a dense labelling associating : dark dots spaced under the basal lamina and fogging less dense labelling in the clarified superficial dermis. Using the patient's antibodies an indirect reaction on normal human skin performed : the same dotted sub laminal labelling was found but with no dermal diffuse reaction product. The study shows the site and the aspect of the Ig deposit in EBA and indicates that the antibodies demonstrated in some patients are reactive with a constituent of the normal superficial dermis.

Epidermolysis Bullosa↗
PubMedDate not supplied

[Comparative ultrastructural study of the inner medullary zone of the kidney of rodents with varying water access in the habitat environment].

Studies have been made on the papillary zone of the kidney in wild rodents Microtus oeconomus, M. afganus, Nesokia indica and Rhombomus opimus, representing related taxonomic species but differing with respect to accessibility to water. In animals with high concentrating capacity, pronounced peculiarities of ultrastructure of descending and ascending parts of Henle's loop, thin epithelial layer in the collecting tubules and poor development of interstitial tissue account for higher level of water reabsorption. On the contrary, cytoplasmic ultrastructure of the collecting tubules in more arid species in simpler, this fact being presumably unrelated to the level of water reabsorption. Therefore, adaptation of the species investigated to the level of water accessibility is accompanied by ultrastructural changes in the inner medullary zone of the kidney.

Adaptation, Physiological↗
PubMed1982

[Retarded schizogony of Plasmodium yoelii yoelii in rodents treated with ethionine or subjected to a methionine deficiency: histological and ultrastructural studies].

Histological and ultrastructural aspects of acute and chronic pre-erythrocytic schizonts of P. yoelii yoelii were studied with: a) acute schizonts in normal rodents; b) chronic schizonts induced in rodents receiving ethionine injections or on a low methionine diet; Experimentally induced chronic schizonts frequently have the same histological aspect as those observed in wild Thamnomys from Africa. The ultrastructural evolution of the vacuole system described by Seureau et al. in acute schizonts is discussed; new evidence is presented to support the hypothesis according to which the contents of the vacuoles are enzymatic in nature. Ultrastructural studies of chronic schizonts show alterations in the sites of synthesis (zones of rough endoplasmic reticulum small and not numerous, absent in the most delayed schizonts; vesicle system poorly developed and also disturbances of nuclear development (slow division, apparently inhibited in the most retarded forms.) A peripheral accumulation of vacuoles in many chronic schizonts without discharge of their contents to the parasitophorous space, might indicate an alteration of their membranes, leaving them unable to fuse with the schizont plasmalemma.

Animals↗
PubMed1982

[Functional restructuring of the ultrastructure of the giant neuron (Retzius') in the medicinal leech and the possible role of Ca++ ions in these processes].

As it has been demonstrated in the giant (Retzius') neuron of the leech (Hirudo medicinalis), at the synaptic activation for 5 sec. and 10 min., ultrastructural changes in the neuron are accompanied with an increasing number of Ca++ ions in hyaloplasm, mitochondria and cytosomes. After activation, the ultrastructural changes increase, and the number of Ca++ ions returns to the initial level. A suggestion is made on a trigger function of Ca++ ions when the neuronal ultrastructure changes under conditions of the synaptic activation.

Animals↗
PubMedDate not supplied

Ultrastructural and biochemical studies in phaeochromocytoma.

The purpose of the work was evaluation of the ultrastructure of phaeochromocytoma and its relation to catecholamine pattern and clinical features. The investigation included 6 patients aged 9-60 years. The urinary excretion of catecholamines and their metabolites as well as their content in the tumour were estimated. Ultrastructure studies were done with the Jem 7 and Jem 100C electron microscopes. Moreover, comparative studies of tissue adrenaline and noradrenaline content were performed in each tumour. The results of the study have disclosed morphological differences of tumours which enabled 3 types of tumours to be distinguished according to their structure and hormonal activity. Moreover, a relationship between the ultrastructure of the tumour and the clinical pattern of hypertension was disclosed.

Adolescent↗
PubMed1981

Ultrastructural changes in endometriotic implants during the menstrual cycle.

This report, the first ultrastructural study of endometriotic implants, compares the ectopic endometrium in 14 patients with that found in the uterus. The ultrastructural features of most of the glands of the ectopic endometrium resemble those of the corresponding glands lining the uterus. Specific ultrastructural characteristics associated with ovulation, such as giant mitochondria and nuclear channel systems, however, could not be detected in ectopic tissue. Although no pathognomonic electron microscopic characteristics were found in the ectopic endometrium, it was generally possible to assign each sample to a particular phase of the menstrual cycle.

Cell Membrane↗
PubMed1982

Ultrastructure of resting and activated storage pool deficient platelets from animals with the Chédiak-Higashi syndrome.

The ultrastructural of platelets from Chédiak-Higashi (CH) and normal cattle, mink, and cats at rest was studied. Platelets from CH animals had a virtual absence of platelet dense granules. Alpha granules, amorphous membrane-surrounded structures, mitochondria, and microtubules of CH bovine platelets were similar in number and appearance to those in normal bovine platelets. Giant CH granules, present in other cells and considered diagnostic of the syndrome, could not be identified in platelets from CH animals. The open canalicular system and dense tubule system were not readily identifiable in resting bovine platelets. The ultrastructure of normal and CH cattle platelets was evaluated at various stages of ADP-induced aggregation. After platelets changed shape during the first phase of aggregation, the ultrastructural appearance of CH platelets was similar to that of normal platelets. The CH platelets composing the aggregates during irreversible aggregation did not appear as activated as did normal platelets, even though the aggregation tracings were similar. Normal and CH cattle platelets treated with thrombin appeared morphologically similar and were characterized by centrifugal movement of granules.

Adenosine Diphosphate↗
PubMed1981

Myotonia congenita. A histochemical and ultrastructural study in the goat: comparison with abnormalities found in human myotonia dystrophica.

Muscle biopsy specimens from the myotonic goat, an animal model of heritable myotonia, were examined histochemically and by electron microscopy. After Periodic acid-Schiff (PAS) staining with diastase digestion, there was increased PAS-positive material within myotonic goat fibers, as compared with those of normal goats. Myotonic muscle stained with alizarin red S, a histochemical stain for calcium, also had an increased staining reaction when compared with muscle from normal goats. Several ultrastructural abnormalities were found in myotonic goat muscle using routine osmium and uranyl acetate staining. These included increased density of the t-tubules, electron-dense material within t-tubules, proliferation and dilatation of sarcotubular elements, and abnormal mitochondria in the myotonic biopsy specimens. To further study muscle ultrastructure, ruthenium red and lanthanum were used as electron microscopic stains with specificity for membranes. There was increased density of the sarcolemma and t-tubules in myotonic muscle stained with ruthenium red as compared to normal, and lanthanum produced a darker staining reaction of the myotonic goat sarcolemma. The histochemical and ultrastructural differences between normal and myotonic goat muscle were interpreted to be consistent with a morphologic basis for the abnormal contraction-relaxation properties characteristic of myotonia.

Adolescent↗
PubMed1981

[Ultrastructure of the basic cell types of human transitional cell bladder cancer].

Electron microscopic examinations of 33 transitional cell carcinomas of the human urinary bladder demonstrated that tumor cells may retain some organ- and tissue-specific features which could be of differential diagnostic importance and indicate the degree of ultrastructural differentiation of this organ tumors. The main parenchymatous elements of transitional carcinoma include superficial (apical location of mitochondria, microvilli on the luminal surface, zones of adhesion, locking), intermediate (elongated shape, few organoids, digital processes, distended intercellular spaces, intercellular bridges), basal (large nucleus, meager cytoplasm), squamous epithelial (tonofibrils, keratohyalin, keratosomes, desmosomes) cells. Tissue-specific ultrastructural features of these tumors consist in specialized contacts (desmosomes, zones of locking and adherence), microvilli, fragments of basal membrane. Ratios of ultrastructural types of tumor cells in transitional cell carcinomas of the urinary bladder vary considerably.

Biopsy↗
PubMed1978

[Fibroblasts and the development of the connective tissue: ultrastructural aspects of biosynthesis, fibrillogenesis and catabolism of collagen].

According to the ultrastructural features, 6 types of fibroblasts are distinguished of which two are immature forms (little-differentiated and young fibroblasts) and the rest (collagenoblasts, myofibroblasts, fibroclasts, fibrocytes) are mature cells with the functional specificity participating in the collagen production, contraction, remodeling, involution and stabilization of the connective tissue, respectively. In their turn, collagenoblasts differ from each other in the intensity of biosynthesis and the mode of collagen secretion from the cell. Fibroblasts also produce proteoglycans which are important in fibrillogenesis. Proteoglycans form cuffing around each collagen fibril as well as are components of microfibrils and floccular material which form the ultrastructural basis of the cementating substance. A system of collagen-lytic enzymes and ultrastructural signs of collagen resorption have been found in fibroblasts attesting to their role in the maintenance of equilibrium between biosynthesis and catabolism of collagen under normal and pathological conditions.

Animals↗
PubMed1981

Ultrastructural study of the medulla of mammalian hairs.

Coordinated studies with the SEM and CTEM have allowed the authors to observe in situ the morphology and ultrastructure of about twenty different types of hair selected on the basis of their different characteristics when studied by optical microscopy. The new data thus obtained make it possible to classify the different types of hairs in a logical order (parallel to Hausman's classification). The classification is based on the fine morphology and the ultrastructure of the medulla and the differences encountered in the main mammalian orders. Furthermore the chronology of these characteristics follows that of mammalian phylogenesis. The ultrastructural characteristics of the medullar of human hair are totally different from those of the hair of all other mammals.

Animals↗
PubMed1978

[Effects of hypertonic solutions on the excitation-contraction coupling of the skeletal muscle fibre of the crab. II. Ultrastructural aspects (author's transl)].

Experiments were performed to investigate the modifications of electrical activity and the loss of contraction by examination of the ultrastructure. These alterations were obtained with a control physiological solution (artificial sea water, ASW) which was made hypertonic by adding sucrose, glycerol, choline chloride or urea. 1. Under these conditions, the ultrastructural results show that: a) all those substances induce a modification of the coupling junction (either diad or triad). This modification can explain the inhibition of the mechanical phenomenon; b) sucrose (Figs. 6C and 6D) and glycerol (Figs. 4A and 4B) induce alterations of the surface membrane and of the tubular system (less important with glycerol). They can explain the decrease of the resting potential and the abolishment or the modification of the action potential; c) in contrast, choline chloride (Figs. 7A to 7E) and urea (Figs. 9A to 9F) only modify the organisation of the coupling junction. The action potential is maintained. 2. A short exposure of the fibre in an isotonic sucrose solution (Figs. 5A to 5D) deeply modifies the tubular system, particularly, in cutting it off from the sarcolemma. 3. Choline chloride and urea produce similar changes in the ultrastructure but as urea is not ionized, it can be added to the ASW to investigate the electrical phenomenon which cannot be modified by contraction.

Animals↗
PubMed1980

Congenital dysgranulopoietic neutropenia: clinical, serologic, ultrastructural, and in vitro proliferative characteristics.

Six children with severe congenital neutropenia and repeated life-threatening infections were investigated by examining clinical features and myeloid cell ultrastructure, cytochemistry, and in vitro proliferation. Despite the presence of neutropenia, normal numbers of colony-forming cells (CFC) were present in blood and marrow specimens, and colony-stimulating activities (CSA) from blood cells and serum were normal or slightly increased in all patients. In vitro maturation of the progenitors to neutrophils was also uniformly present in the colonies. No patients had demonstrable antineutrophil antibodies or serum inhibitors of myelopoiesis. Serum lysozyme levels were normal. Ultrastructural and cytochemical studies of directly sampled marrow cells revealed several abnormalities in most neutrophilic myeloid cells from each of the patients consistent with an intrinsic myeloid precursor cell defect. These included (1) the defective synthesis or degeneration of primary granules, (2) an absence or marked decrease of secondary granules in the few late neutrophils observed in the bone marrow, and (3) the presence of autophagy. Phagocytosis of intact myeloid cells with subsequent degeneration was not observed; however, neutrophil debris was evident in phagocytic vacuoles of marrow macrophages. Our demonstration of ultrastructurally dysmorphic neutrophilic granulocytes, intramedullary cell lysis, normal stem cell numbers, and negative serology is comparable to similar observations of erythroid cells from patients with congenital dyserythropoietic anemia. We therefore hypothesize that the dysgranulopoiesis in these children results in neutropenia and propose the descriptive name congenital dysgranulopoietic neutropenia.

Agranulocytosis↗
PubMed1980

Ultrastructure and biochemistry of two mutants in Hosta (Liliaceae).

In a survey of several plastid chimeras of the genus Hosta two white mutants with C4--type ultrastructure were noted. Mesophyll plastids from the white tissue have an extensive system of peripheral reticula, characteristic of C4 plants, and macrograna or vesiculated thylakoids, characteristic of photosystem I deficient mutants. Microbodies were either absent or in low quantities in these cells. Bundle sheath plastids from the white sectors had a concentration of all organelles, with plastids of typical C4 bundle sheath ultrastructure and numerous, ornate mitochondria. Green restituted sectors of one of these mutants retained the ability to make peripheral reticulum yet had normal Hosta granal formation. Despite these changes the plants show a carbon fractionation like C3 plants. Possible reasons for these ultrastructural modifications are discussed.

Carbon↗