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PubMed1979

[Ultrastructure of the adrenaline-synthesizing neurons of group A1 in the rat brain normally and under emotional stress].

Ultrastructure of A1 group, participating in the central regulation of cardio-vascular functions was studied in normal conditions and at early stages of an emotional stress. Normal adrenalin-synthesizing neurons of A1 group are characterized by a high intensity of processes of synthesis taking place in them. Abundant terminals, mainly adrenergic ones, which form varied contacts with neurons of A1 group, make a peculair feature. The hematoencephalic barrier in the area of A1 group as a sharply specific organization: transport of substances is mediated not only by pinocytosis, but also through fenestrated formations and through interendothelial spaces. Capillaries of the area studied have a powerful innervation--terminals immediately adjoin the vascular wall, sometimes penetrate into the basal membrane. An immediate contact between neurons and capillaries is noted. In the vicinity of the contact, the laminar complex is usually situated having increased in size vesicles, vacuoles, lysosomas, mitochondria; lobes of the invaginated nucleus are also directed towards this place. At an early stage of the emotional stress, when the arterial pressure is kept at the level close to the normal, rather essential changes are noted in neuronal ultrastructure, with significant spatial rearrangements including. Quantitative alterations of organells and reorganization of the neuronal ultrastructural apparatus results in formation of certain new properties and contribute to transformation of the neural cells to a more effective functional level.

Animals↗
PubMed1979

[The ultrastructure of the endings of nerve fibers of ordinary hairs of mammals under normal conditions and during degeneration and regeneration].

At ultrastructural level, three zones are distinguished of the palisade endings of nerve fibers, most of them in contact with the basement membrane of the outer epithelial sheath of the radix pili on rat muzzle. After division of the supplying nerve (n. infraorbitalis) in test animals of the same species, its nerve fibers and palisade endings undergo degeneration, followed by regeneration within 4-5 months. Changes in the ultrastructure of the mentioned nerve elements are thoroughly studied and demonstrated in the course of the two processes. While within 6...12 days of the operation, the palisade endings degenerate, 130 days after the intervention most of them are restored and exhibit an appreciable difference relative to their typical ultrastructure in normal state. The Schwann's cells processes, enveloping degenerated and regenerated palisade endings, similarly display marked fine-structure alterations.

Animals↗
PubMed1977

[Comparative studies on the ultrastructure of human lung and sceletal muscle in shock. II (author's transl)].

The ultrastructure of skeletal muscle biopsies was investigated and compared to lung biopsy material of the same patient in shock. We found almost complete conformity of ultrastructural changes in the micro-vascular system. Capillary endothelia of both tissue types react in a similar way with a more or less distinct swelling of endothelial cells and rarefaction of cell structures as well as constriction of the vascular lumina. Despite an intact structure of the capillary endothelia there is development of oedema in the perivascular areas with escape of plasma components, erythrocytes and granulocytes into the muscle interstitium. Finally, more distant tissue regions are becoming oedematous. While mainly lysosomal enzymes from the large number of infiltrating granulocytes, as well as fatty globules, are made responsible for the damage in the shock lung, the damage of the capillary region in the sceletal musculature is almost certainly caused by hypoxia. We consider muscle biopsy a suitable method to obtain a better knowledge of the microcirculatory situation and of the reaction of ultrastructures in shock.

Biopsy↗
PubMed1984

The blood-tissue barrier of human brain tumors: correlation of scintigraphic and ultrastructural findings: concise communication.

Through the first 2 hr, uptake of [Tc-99m]pertechnetate and of Co-57 bleomycin were assessed in 29 brain tumors and were correlated with the ultrastructure of the tumor's capillary endothelium. No difference in uptake was found between the two tracers. Permeability of brain tumors to these agents was found to be governed by the same ultrastructural features that determine permeability in experimental brain tumors: the type of junction between contiguous endothelial cells in the capillaries. Meningiomas, which showed very high uptake of the radiotracers, demonstrated open or punctate junctions with short fusion of apposed membranes. They also showed a large number of pinocytotic vesicles and fenestrae. Capillaries of tumors without uptake had a small number of short tight junctions (less than 0.25 mu) between adjacent endothelial cells and a relatively large number of long junctions (greater than 0.5 mu). In intracerebral tumors that showed relatively high uptake, the reverse was true: most of the junctions were short and only a few long junctions were found. That uptake of [Tc-99m]pertechnetate and of Co-57 bleomycin depends on tumor capillary ultrastructure (which determines the permeability) suggests the possibility of the use of radiopharmaceuticals as in vivo indicators of tumor permeability. Brain scintigraphy may help to asses brain-tumor availability to non-lipid-soluble chemotherapeutic drugs.

Bleomycin↗
PubMed1977

Ultrastructure of duodenal epithelial cells in patients with active duodenal ulcers and after treatment with cimetidine.

Comparative ultrastructural studies were conducted on biopsy specimens taken under direct vision by endoscopy from the normal duodenum, from the edge of deep and flat duodenal ulcers, and from areas 1 cm away from such ulcers. In addition, the ultrastructure of biopsy tissue from the scar of ulcers which healed after 6 weeks' therapy with the histaminastructural studies of tissue form the edge of both flat and deep duodenal ulcers showed gross pathological changes, particularly with regard to microvilli. Cells from the edge of deep ulcers showed increased secretory activity. Epithelial tissue 1 cm from flat duodenal ulcers exhibited ultrastructural changes far more severe than cells 1 cm from deep duodenal ulcers. The epithelial tissue from the scar area after 6 weeks' treatment appeared capable of regaining a fully functional role, although it was not normal in all specimens.

Cicatrix↗
PubMed1984

Ultrastructural characterization of pulmonary neoplasms. I. The role of electron microscopy in characterization of the most common epithelial neoplasms.

We have attempted to summarize current concepts pertaining to the ultrastructural evaluation of epithelial pulmonary neoplasms, with an emphasis in potential clinicopathological correlations. Routine ultrastructural evaluation of the most commonly encountered pulmonary carcinomas seems to provide, in a significant number of cases, additional information that may be of help in patient management. Immunocytochemistry when employed as an adjunct to electron microscopic evaluation of pulmonary tumors also plays an important role in clarifying morphologic findings. With the advent of specific chemotherapy protocols and future development of monoclonal antibodies in the treatment of neoplasms, accurate tumor classification becomes crucial. The combined use of electron microscopy and immunocytochemistry seems to be extremely useful in providing accurate and reproducible criteria of great potential value in the overall assessment of pulmonary neoplasms. In part II of this study we will address the importance of the ultrastructural evaluation of less common epithelial and mesenchymal pulmonary neoplasms.

Adenocarcinoma↗
PubMed1981

The diffuse endocrine-paracrine system of the gut in health and disease: ultrastructural features.

At least 16 types of endocrine-paracrine cells have been identified ultrastructurally in the gastrointestinal mucosa. The production of hormones and local messengers such as 5-hydroxytryptamine, gastrin, cholecystokinin, somatostatin, secretin, gastric inhibitory peptide (GIP), enteroglucagon (glicentin, GLI), motilin, neurotensin, substance P and the enkephalins, by these cells, has been established. Progress has also been made in cytological studies of gut and pancreatic endocrine tumours. Argentaffin EC cell carcinoids, gastrinomas (of several ultrastructurally different varieties of gastrin cells), L-cell tumours and D-cell tumours are among those cytologically and functionally defined in the gut. Functionally undefined tumours include the so-called non-argentaffin carcinoids arising in various parts of the gut, some of which have been characterised cytologically as gastric ECL cell tumours and gastroduodenal P-D1-cell tumours. Gastrinomas, vipomas and rare argentaffin carcinoids are among gut-related pancreatic endocrine tumours. Non-functional paragangliomas, usually with some neuromatous component, occur in the duodenal wall. Extrapancreatic vipomas display ultrastructural features of ganglioneuroblastomas with peptidergic granules.

Animals↗
PubMed1977

[Ultrastructural findings in the so-called minimal glomerular changes].

Fifty-eight needle biopsies of the kidneys with the light microscopical diagnosis of so-called minimal glomerular lesions were subjected to ultrastructural evaluation. The series contained children and adults under 25 years of age with the mean age of 16.9 years. The most frequent findings were those of the glomerular epithelia: vacuolation and swelling of their cytoplasm in 72.8%, microvilloustransformation in 13.6%. Endothelial lesions were less frequent: swelling and vacuolation of their cytoplasm occurred in 46.6%. The most important ultrastructural lesions appeared to be the mesangial ones. Focal increase in the mesangial matrix was seen in 44.8% and small intralobular scars in 13.6%. True focal increase in mesangial cells was rare (6.9%). The formation of duplicatures of the basement membranes in the glomeruli was exceptional (3.6%). Another important ultrastructural finding was a focal thickening of the basement membrane in a larger number of cases (32.3%). Deposits were found rarely (7 cases, 12.1%) most of them occurring in the mesangium. The cellularity of the glomeruli did not exceed the normal range.

Biopsy↗
PubMed1981

The ultrastructure of the dermo-epidermal junction in lichen planus.

The ultrastructure of the dermo-epidermal junctional area in biopsy material from 5 patients suffering from lichen planus has been studied during treatment with steroids. Tannic acid was used on the tissue blocks in order to provide high and diversified contrast for electron microscopy. The changes observed in the basal cells consisted mainly of degeneration of the mitochondria and disorganization of the tonofilaments. No ultrastructural changes were seen in the basal lamina, apart from occasional gaps, whose significance for pigment incontinence in old lichen planus lesions is discussed. Cellular infiltration was seen in the dermis, while the ultrastructure of the collagen fibrils of the papillary layer was normal. It is suggested that degeneration of mitochondria with subsequent disturbance of the organization and fixation of tonofilaments are events in the pathogenesis of the condition.

Adolescent↗
PubMedDate not supplied

Ultrastructural changes of the rabbit lung tissue during sensitization to antigens.

In order to specify the ultrastructure of changes induced in the rabbit lung tissue during sensitization to antigens - previously studied by conventional methods -, two groups of rabbits were weekly sensitized by intramuscular injections, the first group with complete Freund adjuvant (CFA) only, the second with CFA to which human gammaglobulin was added. Fragments from caudal lobes harvested six days after the 3rd, 4th and 5th injections were processed for electron microscopy. This investigation confirmed the general process of cell accumulation within alveolar walls, interlobular areas and bronchial subepithelial layers previously appreciated histochemically and morphometrically. The predominating cells in both rabbit groups were histiocytes (macrophages) of local and blood origin; a monocyte marginating an alveolar capillary was evidenced. In the rabbits sensitized with CFA only, histiocytes were largely accompanied by lymphocytes; between them some relationships may be ultrastructurally observed. An increased number of fibrils and fibroblasts was also seen in this group. The animals sensitized with CFA containing human gamma-globulin showed active plasmoblasts and plasma cells among histiocytes; this picture corresponded to the high increase of serum precipitins. These ultrastructural changes form the basis on which hypersensitivity reactions may be challenged experimentally and during human immune chronic lung diseases.

Animals↗
PubMed1981

Synthesizing activity and ultrastructural findings of human blood cells after incubation with cis-platinum "in vitro".

The synthesizing activity and ultrastructural appearance of human polymorphonuclears, lymphocytes and platelets obtained from healthy donors were examined after incubation with cis-platinum (cis-Pt). The drug caused a statistically significant inhibition of DNA, RNA and protein synthesis of the lymphocytes, but their ultrastructure appeared unchanged. On the other hand, incubation of polymorphonuclears with cis-Pt did not affect their protein synthesis but caused a decrease in the number of cytoplasmic granules, mitochondrial alterations, and appearance of membrane ruffles. The drug induced neither inhibition of platelet protein synthesis, nor ultrastructural alterations. The selective effect of this drug on the synthesizing activities of human lymphocytes may be of potential value in the treatment of lymphoproliferative and immunological disorders in man.

Blood Cells↗
PubMed1977

Ultrastructure of the liver after 24-hour preservation with various solutions.

The effect of 24-hour preservation with 5% dextrane solution, Collins C3 solution and 5% human albumin solution, as well as of pretreatment with phenoxybenzamine on the ultrastructure of the rat liver has been studied. It was found that 1. the moment of the irreversible damage of the liver cannot be assessed from the electron microscopic picture; 2. though the ultrastructure offers no clue to the exact length of the effectiveness of a preservation procedure, the different methods can be compared among each other; 3. of the investigated solutions the 5% solution of human albumin appeared to be the most favourable, as with this solution the ultrastructural changes appeared late and in the least pronounced form; 4. phenoxybenzamine pretreatment might be of importance in warm ischaemia as it seems to delay the consequences.

Albumins↗
PubMed1984

An ultrastructural cytochemical stain specific for neuroendocrine neoplasms.

Previous work from our laboratory has indicated that the uranaffin reaction, when run under specific conditions, will stain neurosecretory granules. In this ultrastructural cytochemical study, we analyzed the granule-staining properties of 13 normal, 10 abnormal (non-neoplastic), and 138 neoplastic tissues in an attempt to evaluate the specificity of the uranaffin reaction for diagnostic purposes when compared with routinely processed specimens. For the uranaffin reaction, previously fixed tissue stored in buffer was rinsed with 0.9% NaCl and reacted with a 4% aqueous solution of uranyl acetate (pH 3.9) for 48 hours. After three NaCl rinses, the tissue was dehydrated and processed for electron microscopy. The granules of normal or non-neoplastic neuroendocrine cells that stained positively with the uranaffin reaction included pancreatic islet cells, thyroid C cells, adrenal medullary cells, parathyroid chief cells, and the neuroendocrine cells of the intestine. All 42 neuroendocrine neoplasms studied possessed abundant uranaffin-positive granules and included carcinoids, oat cell carcinomas, islet cell neoplasms, medullary carcinomas of the thyroid, pheochromocytomas, carotid body paragangliomas, a pituitary adenoma, Merkel cell carcinomas, parathyroid adenomas, and a neuroblastoma. All 96 control neoplasms that were not classified as neuroendocrine in nature were negative for neurosecretory granules when studied with the uranaffin reaction and included 13 neoplasms derived from endocrine glands, 57 neoplasms from secretory epithelium, 10 of hematopoietic origin, and 16 miscellaneous neoplasms. It was determined that the uranaffin reaction is a useful ultrastructural cytochemical marker for neuroendocrine granules and helped distinguish these cytoplasmic organelles from ultrastructurally similar granules derived from non-neuroendocrine cells.

Adult↗
PubMed1983

Nasal cilia in normal man, primary ciliary dyskinesia and other respiratory diseases: analysis of motility and ultrastructure.

We studied the ultrastructure and function of nasal cilia from non-atopic and atopic non-smokers, smokers, patients with chronic rhinitis and cystic fibrosis, and compared these to cilia from patients with primary ciliary dyskinesia (PCD). Atypical cilia were found in normal subjects and patients with a variety of chronic respiratory tract diseases, but the proportion was small (less than 5%). Ciliary wave form, beat frequency, and mucociliary transport were normal. In patients with PCD, the proportion of atypical cilia and ultrastructural abnormalities was significantly greater than normal subjects and patients without PCD p less than 0.0001. Beat frequency was reduced, ciliary wave form was grossly abnormal, and mucociliary transport was virtually absent. These findings suggest that ciliary ultrastructural abnormalities are related to altered ciliary function and have aetiological relevance in the generalized chronic respiratory tract disease of PCD.

Cilia↗
PubMed1980

Human osteopetrosis: a histological, ultrastructural, and biochemical study.

UNLABELLED: Histological ultrastructural, and biochemical studies of the tissues of a patient with osteopetrosis were done. The bone contained an increased number of osteoclasts which were characterized ultrastructurally by the absence of ruffled borders and clear zones, hallmarks of actively resorbing osteoclasts. In contrast with normal human bone, tissue collagenase was not detected in osteopetrotic bone cultured in vitro, nor was tissue collagenase activity released when the osteopetrotic bone was incubated with parathyroid hormone. No striking abnormalities of parathyroid hormone or calcitonin were found in the blood or parathyroid and thyroid glands. Except for a slight increase in the extent of lysine hydroxylation of bone collagen, no significant biochemical abnormality of collagen was found. The histological, ultrastructural, and biochemical data support the hypothesis that the basic defect in osteopetrosis is cellular and the osteoclasts, in particular, are abnormal. They appear to be unable to resorb bone and cartilage, and they do not appear to respond to parathyroid hormone in a completely normal way. CLINICAL RELEVANCE: Bone marrow transplantation has produced improvement in both experimental animals and humans and should be actively considered in a child with osteopetrosis who is not thriving.

Amino Acids↗
PubMed1980

Cannabis sativa: effects on brain function and ultrastructure in rhesus monkeys.

Two studies, designed to control for as many variables as possible, were conducted in 21 rhesus monkeys, some with brain electrodes and some unoperated, to determine the effects of marijuana on brain function and ultrastructure. Some monkeys were exposed to smoke of active marijuana (using different dose schedules), some were administered delta-9-THC (0.69 mg/kg iv), and others were exposed to smoke of inactive marijuana (from which all cannabinols had been removed). To deliver smoke to the monkeys, two different apparatuses were used. Dose schedules comparable to those of human marijuana smokers were established, as determined by plasma levels of delta-9-THC. After 2- to 3-months' exposure, the monkeys that were heavy- and moderate-smokers of active marijuana, and those administered delta-9-THC iv, developed chronic recording changes at deep brain sites, most marked in the septal region, hippocampus, and amygdala. These changes persisted throughout the exposure period (6 or 8 months) and during the postexposure observation period (1 to 8 months). Brains of these electrode-implanted monkeys, as well as those without electrodes that were exposed to delta-9-THC, showed ultrastructural alterations characterized by changes at the synapse, destruction of rough endoplasmic reticulum, and development of nuclear inclusion bodies. In contrast, brains of monkeys exposed to smoke of inactive marijuana and of unexposed controls showed no ultrastructural changes. The findings indicate that exposure to delta-9-THC, the psychoactive ingredient of marijuana, at doses commensurate with those used by human marijuana smokers can produce permanent alterations in brain function and structure of monkeys.

Animals↗
PubMed1981

[Ultrastructural and cellular functional activity changes in the zona fasciculata of the rat adrenal cortex resulting form the prolonged administration of adrenocorticotropic hormone].

The fasciculata zone cell ultrastructure has been studied in addition to the level of steroidogenesis of rat adrenal glands on days 2,7 and 13 after the administration of ACTH with prolonged action. The marked changes in the ultrastructure of different cells have been noticed, some of which suggest a compensatory stimulation of hormone production, and the others indicate irreversible subcellular injuries. Changes in the cell ultrastructure show the phase character in time to correlate with changes in the activity of the corticosteroid synthesis and secretion.

Adrenal Cortex↗
PubMedDate not supplied

An ultrastructural and cytoenzymological study on the folliculo-papillary thyroid carcinoma.

Authors studied ten cases of folliculo-papillary thyroid carcinoma, using ultrastructural methods and cytochemical techniques for peroxidase and acid phosphatase activities. The most striking ultrastructural features were: disappearance of secretory granules or apical vesicles; nuclei with an irregular shape containing stage I and II inclusions; two types of cells: with dilate endoplasmic sacks filled with a granular material, or rich in closely packed mitochondria, some of them showing dystrophic lesions with round, dense bodies or tightly packed parallel filaments and numerous phagolysosomes. The peroxidase activity was present as black DAB precipitates in the nuclear envelope and sometimes around colloid droplets, or was completely absent from some cells. The acid phosphatase activity was found as unhomogeneous Pb precipitates inside the lysosomes. The ultrastructural and cytoenzymological pattern suggests marked alteration of the synthesis, storage and secretion of the thyroid hormones. Keeping in mind that results of radio-iodine treatment depend mainly on the histologic type of the thyroid carcinoma, the cooperation between radiotherapeutist and pathologist is emphasized.

Acid Phosphatase↗