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PubMed1989

Ultrastructural features that relate to tumor cell behaviour in human breast carcinomas.

Human breast tumor biopsies were studied by transmission electron microscopy for ultrastructural characteristics that might be associated with tumor cell function and behaviour. Features related to the state of cell differentiation and tumor cell detachment were evaluated and discussed. The ultrastructure of loose cells at the tumor periphery is compared with that of coherent cells in interior regions. Structural information has been analysed by taking into account available biochemical data for interpretation of cell function. The value of the parameters chosen for study is discussed. This study shows that each tumor needs to be evaluated independently for its specific ultrastructural features. Electron microscopic data becomes more relevant when interpreted in conjunction with histological diagnosis and clinical findings.

Adenocarcinoma, Mucinous↗
PubMed1985

Ultrastructural morphometric cell evaluation in chronic lymphocytic leukaemias.

The present study was undertaken to check whether there is a correlation between the clinical stage and the ultrastructural morphometric picture of leukaemic cells. The investigations concerned 12 cases of chronic lymphocytic leukaemia. Qualitative morphological differences could not be detected between cells originating from various clinical groups. Morphometric ultrastructural analysis, however, revealed differences in the volume fraction of cytoplasmic cell components, not only between clinical groups, but also within them. None of the clinical groups were homogeneous, but the cases classified to groups 0, I and II were uniform as regards the volume fractions of the nucleus and some cytoplasmic components. Ultrastructural morphometric studies seem to suggest that counterparts to the clinical state may be found in the morphology of leukaemic cells.

Adult↗
PubMed1989

[Ultrastructure of the epidermis in laboratory rats under normal conditions and after percutaneous administration of an organophosphate].

For the study of the normal epidermal layers of the stratum basale, stratum spinosum, stratum granulosum and (male rats at the age of 2 years) were used. Skin samples were obtained from the spinal area and processed by the method of transmission electron microscopy to get semithin and ultrathin sections. An electron microscopical examination preceded by an evaluation of the semithin sections in the light microscope showed that the epidermis of both age groups contained keratinocytes and Langerhans cells. Keratinocytes are typically arranged in epidermis layers of the stratum basale, stratum spinosum, stratum granulosum and stratum corneum. These layers are of different ultrastructure. The Langerhans cells are localized suprabasally in the epithelium. In the course of keratinization, prominent ultrastructural changes in keratinocytes occur. The cell organelles of keratinocytes including the nucleus disappear and the formation of specific cell components--prominent bundles of tonofilaments, keratohyalin granules and keratinosomes--can be observed. Keratinized cells of the stratum corneum exhibit a homogeneous or fibrillar inner structure. Langerhans cells contain characteristic cytoplasmic organelles--Langerhans granules. The epidermis of old rats differs from that of young animals in a special arrangement of the dermo-epidermal junction. The most typical change (in comparison with the epidermis of young rats) is the presence of multiplied lamina densa. The qualitative study of the normal epidermis of the laboratory rat is completed by morphometric analysis. The measurements concern keratinocytes of the stratum basale. Cell dimensions under the light microscope as well as some cell organelles in ultrathin sections are evaluated. Another part of the study is aimed to estimate morphological changes in the epidermis of rats which were percutaneously administered a toxic organophosphate. In this experiment, the tissue processing for electron microscopy could be realized only when the exposed epidermal area had been previously decontaminated. A group of intoxicated animals was therefore compared with a control group, the epidermis of which was affected by the decontaminating agent only. The ultrastructural changes noted in the epidermis of intoxicated animals show no specificity. Damaged membrane organelles and vacuoles in keratinocytes, dense cells, dilated epidermal intercellular spaces containing the material of medium density, etc. are present. Furthermore, the above-mentioned changes proved to be manifestation of a combined effect of the proper toxic substance and the decontaminating agent.

Aging↗
PubMed1989

[Ultrastructure of human cancer cells during mitosis].

200 mitotic cancer cells from 35 varieties of human malignant tumor were studied by electron microscope. The results showed that: 1. Besides the a typical mitotic figures observed under light microscope, there was no significant difference in ultrastructure during the mitotic phase between cancer cell and non-cancer cell; 2. Judging by the ultrastructure of the tumor cell, about 90% of mitotic tumor cells seemed to be undifferentiated, there was no unique characteristic by which a cell differentiation could be made. Only 10% of the mitotic tumor cells belonged to poorly differentiated cells with the cell origin identified. None of the mitotic figures was found in well-differentiated tumor cells. Pathologically, it was reasonable to classify the tumor according to the degree of cell differentiation; 3. During mitosis, the nucleoli disappeared completely or presented themselves in small pieces scattered in the vicinity of the chromosome. No euchromatin was seen and most of polyribosomes were depolymerized into monoribosomes. The ultrastructure seemed to indicate that protein synthesis was inhibited in the mitotic cycle; and 4. In about one half of the mitotic tumor cells, paired cisternae (or confronting cisternae) were found in the cytoplasm, while paired cisterna was observed in a few cells among the thousand tumor cells in the interphase, so paired cisterna was obviously related to the mitotic cycle.

Cell Differentiation↗
PubMed1989

Ultrastructural reappraisal of endometrial glandular changes in women wearing Cu-T200 device for longer duration.

The present communication deals with the effects of Copper-T200 Sq mm intrauterine device on the endometrial glands in the women using it for a longer duration i.e. up 8 years. The ultrastructural changes in the lining endometrial glands were studied during both non-ovulatory and ovulatory phases of the menstrual cycle. The ultrastructural studies demonstrated significant progressive changes in the lining endothelial cells of endometrial glands. The findings showed marked accumulation of glycogen in the cells in secretory phase of the endometrial cycle. Ultrastructural changes in glandular lining cells were more pronounced in women using Cu-IUCD for 4-8 years having distorted morphology with disrupted cell organelles, swollen mitochondria, irregular pattern of microvilli, deposition of electron dense material on cell surface and narrowing of glandular lumen.

Adult↗
PubMed1989

Ultrastructure of epithelial cells in rat's epididymal caput in experimental hyperprolactinemia induced by metoclopramide.

The aim of the performed studies has been to find out wether or not the ultrastructural alterations of the epithelial cells in the rat's epididymal caput occur in hyperprolactinemia induced by metoclopramide and to see if the observed changes are of reversible character. It has been revealed that prolactin concentration was twice as high as in control animals due to peritoneal administration of metoclopramide in a dose of 2.2 mg/kg body mass, given for 14 days. The ultrastructural alterations in the principal cells of epididymal caput affected cellular organelles being involved in proteins synthesis, glycosylation, secretion as well as energetic processes. They were manifested by decreased amount of rough endoplasmic reticulum, widening of its cisternae combined with degranulation, distension of Golgi apparatus cisternae, elevated number of vesicles in apical part of the cells, and changes in mitochondria. The termination of metoclopramide administration made prolactin concentration exhibit values being almost similar to those determined in control rats, whereas the ultrastructural changes in the principal cells were found to be reversible.

Animals↗
PubMed1989

[The reappraisal study of the ultrastructure of Alzheimer's neurofibrillary tangles in three cases of progressive supranuclear palsy].

Progressive supranuclear palsy (PSP) is characterized by symptoms of disturbance of eye movement, nuchal rigidity, parkinsonism and subcortical dementia. Its pathology reveals that Alzheimer's neurofibrillary tangles (NFTs) are situated especially in the nuclei of basal ganglia and brainstem. It has been pointed out that NFTs observed in PSP are composed of straight tubules, the width of which is about 15 nm. This report is to reappraise the ultrastructure of NFTs observed in three cases of PSP. They are case 1; 69-year-old male, case 2; 62-year-old female and case 3; 65-year-old male. The clinical features of three cases were characterized by above-mentioned symptoms. Many NFTs were observed in brainstem of case 1 and 3. NFTs seen in brainstem of case 2 were in a small amount. In case 1 and 2, there were many NFTs in cerebral cortex, especially in parahippocampal gyri and other limbic areas. We examined the portions of frontal cerebral cortex, parahippocampal cortex, the basal nucleus of Meynert, oculomotor nucleus, substantia nigra, pontine nuclei and locus caeruleus of case 1, substantia nigra, red nucleus and inferior olivary nucleus of case 2, and Ammon's horn, globus pallidum, subthalamic nucleus, substantia nigra, oculomotor nucleus, pontine nuclei, locus ceruleus and inferior olivary nucleus of case 3. Ultrastructurally, NFTs of frontal cortex of case 1 consisted of twisted tubules and those of hippocampal and parahippocampal cortices of case 1 consisted of straight and twisted tubules, being observed separately in neurons. The NFTs of brainstem of case 1 and 2 were mainly composed of 12-17 nm straight tubules, and twisted tubules occasionally intermingled with straight components. In locus ceruleus of case 1, a single straight tubule could be seen in the bundles of twisted tubules. NFTs of case 3 were composed of only straight tubules, the width of which was about 15 nm. Twisted components were not observed in neurons of each nuclei of case 3. The characteristic ultrastructure of NFTs in PSP has been an appearance of straight tubules, however, twisted tubules were occasionally observed in this study. There are several case reports which demonstrated an appearance of both straight and twisted components. It is easily presumed that the process of aging takes part in the accumulation of twisted fibrils. However, it is now under consideration why twisted tubules are also observed in PSP. To summarize this study, the cases with many NFTs observed in widespread cerebral cortex may have a tendency to show both straight and twisted tubules.

Aged↗
PubMed1989

Preservation of myocardial ultrastructure after 24 hours of Klebsiella sepsis: histologic, functional, and biochemical correlations.

Myocardial function with ultrastructure and high energy phosphate levels in dogs was correlated after 24 hours of sepsis using live Klebsiella aerogenes. All animals developed progressive hemodynamic deterioration over a 24 hour period. Mean arterial pressure decreased from 148 +/- 7 mmHg to 85 (P less than 0.01) and cardiac output decreased from 3.43 +/- .31 to 1.6 +/- 0.5 L/min. Left ventricular stroke work decreased from 48.2 +/- 5 to 18.1 +/- 6 gm-meters (P less than 0.001). Systemic and pulmonary vascular resistances were increased at 24 hours (3,538 +/- 27 to 7,404 +/- 1,400 dyne/sec/cm-5 (P less than 0.01), and 185 +/- 20 and 619 +/- 90 dyne/sec/cm-5 (P less than 0.001), respectively. Left ventricular function curves at 24 hours showed a fixed low output. However, myocardial ultrastructure was preserved and high energy phosphate levels remained normal. These observations correlate well with the changes seen clinically in early gram negative sepsis in hypovolemic patients. Thus, this appears to be a suitable model for further investigation of the effects of gram negative sepsis on myocardial performance, ultrastructure, and maintenance of energy stores.

Animals↗
PubMed1989

[Ultrastructural study of the colon after massive intestinal resection in rats].

The modifications suffered by the colon after massive intestinal resection (RIM) have been barely studied, especially from the ultrastructural point of view. On the basis of optical microscope studies we planned this experimental study to evaluate fundamentally the ultrastructural changes in the colonic mucosa and its cellular elements. A total of 115 Wistar rats weighing 350 to 550 grams were used. Twenty animals constituted group 0 (controls), 30 underwent intestinal section (group I) and 65 were submitted to resection of 90% of the intestine (group II). After weighing, the animals were sacrificed by groups on days 15, 30, 45 and 60 of the operation to obtain histologic samples of the ascendant colon for study by transmission (MET) and scanning (MEB) electron microscopy. All the animals resected showed statistically significant weight loss (p less than 0.001), an expression of short intestine syndrome. Groups 0 (controls) and I (intestinal section) did not evidence important ultrastructural changes. In contrast, although in the initial electron microscopic scan the colonic mucosal surface offered a normal aspect, at 45 days it presented irregularities, without the appearance of villi. Days 60 there were deep folds and the mucosal surface had acquired a foliaceous aspect similar to that of the surface of the small intestine of the rat. The abundance of microorganisms adhered to the surface, constituting clumps of bacteria, was striking. Transmission electron microscopy confirmed the greater number and height of the enterocytes, covered by well-developed apical microvilli with dimensions that increased throughout the experiment. The cellular nuclei are voluminous and occasionally have various nucleoli. The cytoplasm showed changes that affected fundamentally the mitochondria.(ABSTRACT TRUNCATED AT 250 WORDS)

Adaptation, Physiological↗
PubMed1989

[The surfactant system and ultrastructure of the lungs after surgical correction of cardiac defects during extracorporeal circulation].

Using bronchoalveolar lavage (BAL), two-dimensional thin-layer chromatography, and electron, microscopy, the surfactant system and ultrastructure of the lung were examined in 32 patients with mitral valvular disease before cardiac interventions, after closed mitral commissurotomy, and surgeries under extracorporeal circulation (EC). The magnitude of changes in the pulmonary surfactant and structure was shown to be determined by the degree of circulatory decompensation and to vary with duration of the disease. In 23.7% of the patients, there were significant changes in the pulmonary surfactant system and ultrastructure, which were characterized by phospholipid metabolic disturbances in the surfactant, destructure of osmophilic lamellated corpuscles of type II alveolocytes (AII), decrease in their relative volume, a substantial increase in the minimal BAL superficial tension, and aerohematic barrier fibrosis. Concurrent with the magnitude of morphological changes in the lung, time of EC, composition of a perfusate, the presurgical abnormality of the surfactant system is essential to the development of its postperfusion insufficiency and pulmonary dysfunction. The pulmonary ultrastructural alterations in these patients were expressed by impairment in capillary endotheliocytes, their accumulation of leucocytic aggregates, interstitial and intracellular edemas, partial alveolar collapse, destructive-and-necrotic and compensatory-and-adaptative changes in AII. The above abnormalities were seen in 27.7% of the patients operated on under EC.

Adult↗
PubMed1989

Synaptic ultrastructure of functionally and morphologically characterized neurons of the superficial spinal dorsal horn of cat.

Recordings of neuronal unitary discharges evoked by primary afferent input were made in the superficial part of the spinal cord's dorsal horn, the marginal zone and substantia gelatinosa (also known as laminae I and II), using fine micropipette electrodes filled with HRP. After physiological characterization with respect to primary afferent input, HRP was injected intracellularly iontophoretically into the recorded neuron. Following histochemical processing, the neurons so delineated were studied at the light and electron microscopic levels. No clear relationship between function and either general cellular configuration or synaptic ultrastructure appeared in these analyses, although the concentration of dendritic distribution could be related to the nature of primary afferent excitation. Nocireceptive cells had dendrites mostly branching and ending in lamina I and IIo, while the dendrites of innocuous mechanoreceptive cells arborized principally in lamina II and III. Glomerular synaptic complexes (large, complex arrays of axonic and dendritic profiles with synaptic interconnections) were found to contact a few neurons of both the nocireceptive and mechanoreceptive classes. All neurons received large numbers of simple axonic contacts (small axonic boutons with only 1 or 2 synaptic contacts with a single postsynaptic profile). A degree of specificity in the presynaptic articulations appeared to be reflected by the observations that (1) nocireceptive neurons were never found to receive synaptic contacts from boutons which resembled the known ultrastructure of peripheral innocuous mechanoreceptors, and (2) mechanoreceptive neurons were never seen to receive synaptic contacts from boutons which resembled the known ultrastructure of primary afferent nocireceptors. The axons of the labeled neurons of both nocireceptive and mechanoreceptive classes terminated in simple axonic synapses. All classes of neurons participated in dendrodendritic contacts; however, only some mechanoreceptive neurons had dendrites containing vesicles that were presynaptic to other profiles. No nocireceptive neurons, regardless of gross configuration, were found to have vesicles in their dendrites, but 3 nocireceptive neurons received synapses from presynaptic dendritic profiles.

Afferent Pathways↗
PubMed1989

Ultrastructural changes in parietal cells in iron deficiency anemia.

Eighteen patients with iron deficiency anemia (IDA) and 14 age and sex matched control subjects were studied with regard to ultrastructural changes in parietal cells. The control subjects had normal hemoglobin and serum iron levels and endoscopic examination of the upper gastrointestinal tract. Thirteen cases of iron deficiency anemia had chronic superficial gastritis on light microscopy. Ultrastructural abnormalities in the parietal cells, such as indented or pyknotic nucleus with irregular outline, grossly distorted canalicular system, abnormal large empty spaces in the cytoplasm and paucity of mitochondria, were demonstrated in all IDA patients but not in controls. The presence of superficial gastritis and ultrastructural changes were not related either to hemoglobin or serum iron levels in the IDA group.

Adolescent↗
PubMedDate not supplied

The ultrastructural effect of amprolium medication on development of Eimeria adenoeides in turkeys.

The ultrastructural appearance of first-generation schizonts of Eimeria adenoeides was markedly altered in turkey poults fed 0.0125% amprolium-medicated feed. When compared with development seen in unmedicated control birds 48-72 hr postinoculation (PI), most of the schizonts present in the medicated birds were fragmented, contained enlarged nuclei, had swollen endoplasmic reticulum and Golgi apparatus, and showed no budding of merozoites. Other schizonts were almost completely degenerated and contained pyknotic nuclei, dense cytoplasm, and large intracytoplasmic vacuoles containing membrane whorls or lipid droplets. A few mature schizonts were seen in the medicated poults, and these did not appear to differ ultrastructurally from those seen in unmedicated control birds. Ultrastructurally normal second-generation schizonts and the sexual stages were also seen in small numbers in the medicated turkey poults 72-120 hr PI. Mature sexual stages were seen much earlier in medicated turkeys--at 96 hr PI--than in the unmedicated poults.

Amprolium↗
PubMed1989

[Correlation between hepatic microcirculation ultrastructural changes and hepatic dysfunction in chronic hepatitis B].

The author observed the ultrastructural changes of hepatic microcirculation and the function of the liver in 41 cases with chronic hepatitis B confirmed histologically. The main ultrastructural changes found in patients were swelling of the endothelium of hepatic sinusoids, hyperplasia of Kupffer cells and decrease of fenestrae in the endothelium. Proliferation of monocytes and fat-storing cells was also found in the lumina of hepatic sinusoids and space of hepatocytes and perisinusoid. The basement membrane in hepatic sinusoids and the base of hepatocytes were formed in the patients with marked pathologic changes of the liver, especially in CAH with cirrhosis. The observations also showed that whatever extent of hepatic microcirculation changes, all of them had more or less elevation of SGPT and ZnT or TT. As soon as hepatic function was impaired slightly, there occurred hepatic dysmicrocirculation. But in the cases of severe ultrastructural hepatic dysmicrocirculation serum gamma globulin elevation values and A/G ratio exchanges were much higher than those in the cases of slight changes. There was some significance on the judgment of sick condition, slight or severe. Values of the elevation of serum gamma globulin and A/G ratio exchanges were much more obvious than SGPT, ZnT and TT changes. These findings suggest that the extents of pathological changes and dysfunction of the liver in chronic viral hepatitis B are correlated to the extent of hepatic microcirculation impairment. So in the treatment of chronic hepatitis early administration of medicine to improve the liver microcirculation should be considered.

Adolescent↗
PubMed1989

Ultrastructure of globule leucocytes isolated from rat tracheal epithelium.

The ultrastructure of globule leucocytes isolated from rat tracheal epithelium is described. The isolated globule leucocytes appear as rounded mononuclear cells with a diameter of 6 to 8 microns. The often indented nucleus is usually eccentrically located in the cell. The characteristic intracytoplasmic membrane-bound granules vary greatly in electron-density, size, shape, and internal structure. On the basis of their internal structure, four types of granules could be distinguished. They may reflect different stages in the process of accretion and utilization of the granule content. The prominent juxta-nuclear Golgi complex is presumably involved in the formation of granules. Striking in the isolated tracheal globule leucocytes are bridge-like connections between several granules, the significance of which is still unknown. Besides the granules and the extended Golgi complex, the cytoplasm contains inconspicuous organelles. Except for the bridge-like connections between intracytoplasmic granules, the ultrastructure of the isolated globule leucocytes resembles very well the ultrastructure of similar cells previously described in tissue sections of trachea and other organs of different mammalia. It is concluded that the used isolation method produces globule leucocytes which are morphologically well preserved and apparently undamaged. This may be a significant step towards understanding the function and origin of these peculiar cells.

Animals↗
PubMed1989

[Cytotoxic effects of changrolin, lidocaine and amiodarone on ultrastructure of cultured rat beating cardiac myocytes].

Ultrastructural and morphological alterations of cultured rat beating cardiac myocytes treated with changrolin (CRL), lidocaine (Lid), and amiodarone (Ami) were studied. After the cultures were treated with CRL 100 micrograms/ml for 24 h, the beating of the myocytes stopped, the configuration and fine structure were destroyed, while the nuclei showed pyknotic deformation and reduced in size. The membrane and structures of mitochondria were disrupted and myofibrils fragmented and disrupted. In addition, a lot of vacuoles with characteristic dense particles were found in the cytoplasm. Similar alterations were seen when Lid 1000 micrograms/ml and Ami 50 micrograms/ml were added to the cultures. Normal beating networks of myocytes were examined under inverted microscopy after the cultured cells were treated with CRL 25 micrograms/ml, Lid 250 micrograms/ml or Ami 6.25 micrograms/ml. The ultrastructure of some regions of the myocytes showed very slight damage. The results indicated that the dosage of CRL and Lid generally used in anti-arrhythmic therapy basically exerted no harm to myocytes. However, caution should be taken when Ami was given intravenously, since its effective serum concentration was close to the dosage which could cause slight damage to the ultrastructure of cultured cells.

Amiodarone↗
PubMed1987

[Ultrastructure of brain tumor].

Ultrastructure of 15 brain tumors (6 astrocytomas, 5 meningiomas, 2 medulloblastomas and 2 Schwannomas) was observed by transmission electron microscope. In astrocytoma, both the fibrous and protoplasmic astrocytes were found. There were abundant capillaries among the tumor cells. The glia limitans outside the base membrane of certain capillaries were destroyed to different degrees. It indicates that the blood brain barrier may be damaged. Ultrastructurally, medulloblastoma cells may be divided into types I and II. The former was poorly differentiated but the latter was differentiated differently. Meningioma was similar to Schwannoma with complex cell membrane projections. The former had a lot of round mitochondria and filaments in the projections, between which desmosomes were observed. Schwannoma had the typical collagenous fibers among the projections. As to the epithelioid ultrastructure of meningioma, the authors speculate that the majority of meningiomas originate from the mesothelial cells of the arachnoid granulations.

Astrocytoma↗
PubMed1987

[Ultrastructure of adenohypophyseal cells of white rats subjected to the effect of a benzodiazepine in chronic form].

The ultrastructure of the pars anterior (adenohypophysis), treated with diazepam (2.5 mg/Kg) has been studied by thin sections and electron microscopy. The structure of Thyrotrophs, Corticotrophs, Gonadotrophs, and Mammotrophs cells were described. Ultrastructural modifications were not observed. It is concluded that the chronic treatment with diazepam did not produce any visible ultrastructural effects in the secretory cells of the adeno hypophysis; maybe because the diazepam has a short life time and due to the small effect of the diazepam metabolites in this species.

Animals↗