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At least 1,189 records · Page 66Linked to original sources
PubMed1978

[Morphology and deformability of erythrocytes in muscular dystrophy].

In recent years, the presence of red cell morphological abnormalities in patients with Muscular Dystrophy has made the object of numerous, often contradictory reports. A possible source of such confusion may lie in the fact that human erythrocytes are extremely sensitive to morphologic transformations resulting from various manipulations or environmental conditions in vitro. We have examined the morphology and deformability of erythrocytes from 7 patients with Duchenne and 9 patients with Steinert (myotonic) Muscular Dystrophy. To avoid preparation artifacts, fresh, unwashed red cells suspended in their own plasma were examined under phase contrast microscopy for the presence of either echinocytes and stomatocytes. Deformability was measured by filtration of dilute cell suspensions at constant flow rate through nucleopore membranes (nominal pore diameter = 3 micron). No significant difference was found between the patients' cells and those of 22 healthy volunteer controls. We conclude that previously reported abnormalities may have been the result of preparation artifacts. It appears possible, however, that erythrocytes from Muscular Dystrophy patients may be more sensitive than normal ones to certain stimuli originating from red cell manipulations in vitro.

Adolescent↗
PubMed1985

[Mechanisms of cellular multinucleation as affected by cytochalasin B in a culture of transformed fibroblasts].

The multinucleation of cytochalasin B was studied by means of phase contract microscopy and time-lapse cinematography. Several types of alteration of normal cytokineses resulted in the formation of multinucleated cells. The main way of multinucleation consists in the complete development of a cleavage furrow with the formation of daughter cells and an intercellular bridge that is followed by the fusion of these cells due to extending the entercellular bridge. These results suggest that the terminal stage of cytokinesis is the most sensitive to cytochalasin B.

Animals↗
PubMed1984

Effect of microtubule inhibitors on the expansion of hypoblast and margin of overgrowth of chick blastoderms.

The effect of the microtubule inhibitors, Nocodazole and taxol, was studied on the expansion of fragments of chick hypoblast (8 to 10 h incubation) and of margin of overgrowth (24 h incubation) cultured on artificial substrata and on the epiboly in intact blastoderms (24 h incubation). Immunocytochemical staining of these cells with antiserum against tubulin showed that 1 micrograms Nocodazole/ml caused disassembly of microtubules, and that 1 microgram taxol/ml led to increased but unordered assembly. The solvent dimethylsulphoxide had no effect. At these concentrations both microtubule inhibitors led to rapid arrest of the expansion of fragments of hypoblast and of margin of overgrowth in culture, and of the epiboly in intact blastoderms. Time-lapse films showed that inhibition of expansion in both situations was reversible within 2 h after removal of the drugs. Phase-contrast microscopy showed remarkably little difference between the morphology of treated as compared to untreated cultures. Measurements of the height of the cells on sectioned fragments of margin of overgrowth showed no differences between treated and untreated cultures. These results suggest that the cytoplasmic microtubule complex is important both for epiboly and for the migration of hypoblast cells in the chick blastoderm. The mechanisms of this microtubule-related migration are not understood.

Alkaloids↗
PubMed1984

[Urinary sediment in acute renal insufficiency. Diagnostic and prognostic value of phase-contrast microscopic examination].

Living cells from the urinary tract can be examined by phase-contrast microscopy in a pellet obtained by centrifugation of 10 ml of freshly voided urine. Once these cells have been identified and classified according to their sources, their respective proportions can be evaluated, thus providing some information on the renal structures affected. Urine sediment examination was performed in 60 cases of acute renal failure in order to determine the relationship between the abnormalities encountered and the clinical or histological diagnosis. An abnormal sediment was always associated with parenchymal acute renal failure. Cellular debris and casts were abundant in acute tubular necrosis and less numerous in toxic acute renal failure than in failure resulting from shock. The finding of deformed erythrocytes was strongly suggestive of glomerular nephropathy, a diagnosis which was confirmed by renal biopsy in almost every case.

Acute Kidney Injury↗
PubMed1983

Hyposplenism in systemic lupus erythematosus.

Splenic function as measured by number of vacuolated red blood cells (RBC) seen with phase contrast microscopy was studied in 44 patients with systemic lupus erythematosus (SLE). Two of 44 patients (4.6%) had increased percentages of vacuolated RBC (8.4% and 30.6%) indicative of hyposplenism. Both patients had inactive disease at the time, were on low doses of corticosteroids, and had persistence of vacuolated RBC when restudied 2 and 4 months later. The present study confirms the association of hyposplenism with SLE and indicates that the incidence of hyposplenism in SLE is about 5%.

Adolescent↗
PubMed1984

[Cytomorphology of the basic histological forms of thymus tumors (cytohistological parallels)].

Cytomorphology of various histological types of thymic tumours was studied on transthoracic punctures and scrapes from the operatively removed thymomas. Cytological material was stained by Pappenheim with hematoxylin and eosin, by modified Papanicolau' method as well as by means of luminescent and phase-contrast microscopy. Histological slides were stained with hematoxylin and eosin. Cytological diagnostics of thymomas is based on the detection of the two main types of cells--lymphoid and epithelial. Hassals' bodies are detectable very rarely in the material of lymphoid thymomas punctures. The cytological features characteristic of lymphoid, lymphoepithelial, epithelial, and spindle-cell thymoma are described. The identity of cell types in both cytological smears and histological slides is stated, taking into account their changes in these two research methods.

Biopsy, Needle↗
PubMed1984

The use of subcutaneously implanted araldite disks for microstructural studies of inflammatory macrophages.

Subcutaneously implanted epoxy resin disks can be used instead of glass coverslips in mice to recruit inflammatory macrophages. Implanted araldite disks exhibited large numbers of macrophages on both surfaces which could be observed conveniently by light and phase contrast microscopy. Most importantly, the disks can be embedded directly in an araldite mixture for the preparation of thin sections for electron microscope examination.

Animals↗
PubMedDate not supplied

Microridges of neoplastic cervical cells. A phase-contrast study.

Fifty consecutive cervical smears representing dysplasia, carcinoma in situ or invasive cancer were examined by phase-contrast microscopy for the presence of cells with microridges. In a majority of cases, some neoplastic cells exhibited microridges. In more advanced neoplasias, the microridges were less frequent. The absence of microridges does not appear to be a characteristic of cancer per se but may be an indicator of the degree of squamous maturation of the cell.

Carcinoma, Squamous Cell↗
PubMed1977

[Morphological diagnosis of Pneumocystis carinii].

Pneumocystis carinii pneumonia can only be diagnosed once the microorganism is demonstrated. The authors review and illustrate various staining technics, and discuss for each of them specific advantages. All samples must by systematically examined both by phase contrast microscopy and by light microscopy after Gomori-Grocott and Gram-Weigert stains. This morphological study is completed by ultrastructural photographs.

Humans↗
PubMed1981

[Human ovarian myosarcoma and its cell culture (author's transl)].

One case of a very rare myosarcoma of ovarium origin was observed and establishment of its cell lines from the fluid obtained by paracentitis was accomplished. This report is on the determination of the tumor and the biological characteristics of its cultured cells. (Determination of the tumor) (1) This tumor was diagnosed as a malignant of the right ovary, using bimanual examination, selective angiography of the uterine artery, ultrasonic tomography, and abdominal ascitic cell examination. (2) The morphological type of tumor was based findings of hematoxylin eosin. Silver, Mallory and phosphotungstic acid hematoxylin stainings. The tumor was diagnosed as an ovarian sarcoma and probably myogenic. However, a clear cross strain could not be demonstrated. (Cell biological characteristics) (1) Morphological characteristics of cultured cells: a) Phase-contrast microscopy and Papanicolaou staining revealed round or short and spindle shaped cells, with markedly enlarged nucleoli. These proliferated without exhibiting any tendency of contact inhibition. Also frequently recognized were giant cells, multinuclear cells, an some bizarre such as a starfish-shaped cell. b) Electron microscopy revealed that bundles of fibrils regarded as myofibrils existed in the cytoplasma, with dense patches within them, but a cross strain could not be demonstrated. (2) Morphological characteristics of the tumor cells grown in a nude mouse: a) The tumor cells demonstrated similarities to the original tissues by of H.E., Silver, and Mallary stainings. b) A number of fibrils recognized by the electron microscopic observation were 100 A in width and were arranged in a concentric circles. In addition to the light microscopic findings, the above findings indicated that this cell line originated from myogenic sarcoma. (3) Biological characteristics of the cultured cells: a) The number of chromosomes varied widely and spread aneuploidically, the highest chromosome number was 76. b) Doubling time, Saturation density, and plating efficiency was 31.2 hr, 1.2 x 10(5)/cm2 and 43.9% respectively. c) These cells had a high sensitivity for trypsin and started morphological change rapidly.

Animals↗
PubMed1981

[Reactive changes in autonomic synapses during frequency electric stimulation].

Reactive modifications of synapses of isolated intratrunkal vegetative neurones induced by high frequency orthodromal electric stimulation have been examined by vital phase-contrast microscopy, electron microscopy, vital staining with methylene blue in conjunction with concurrent electrophysiological control Flocculent aggregation of the synaptoplasma and vesicles has been discovered, which is associated with higher adhesiveness of modified proteins. There have been also discovered matrix translucence and rounding of the living synaptic buds, which is accounted for by segregation of the hydration fraction of the neuroplasma. The decrease in the number of light synaptic vesicles is accompanied by the appearance of osmiophilic, myelin-like bodies, dense-core vesicles and glycogen-like granules. An attempt has been made to validate the process in terms of the colloid-chemical conception.

Action Potentials↗
PubMed1982

[Mechanism of a universal supravital reaction of varicose changes of neurites].

By means of vital phase-contrast microscopy in neurites, proteolitically isolated from the neural system in representatives of 6 types of invertebrates inhabiting the White Sea and various Chordata, a comparative histological investigation has been performed to study certain reactions of varicose deformities. Solutions of the medium with a decreased ionic strength, prolonged survival etc. have been used as irritants producing varicosities. This reaction, considered to be universal, is absent in thick and gigantic fibres. It develops, first of all, in fine preterminal neurites of any localization and does not depend on the level of the animal's organization and its neural system. In the mechanism on varicosity formation, appearance of the hydrated peripheral fraction of neuroplasm is essentially important. This process is more general and is observed in all neurites.

Animals↗
PubMed1995

Anticoagulant-induced pseudothrombocytopenia and pseudoleucocytosis.

Pseudothrombocytopenia (PTP) is the phenomenon of falsely low platelet counts due to in vitro platelet clumping in the presence of platelet autoantibodies and anticoagulants. We assessed anticoagulant-dependence, time course of platelet counts and impact of different counter devices on the phenomenon. Blood of 10 persons with previously recognized pronounced EDTA-dependent PTP was collected into 7 different anticoagulants and counted after different intervals in parallel in a Coulter T540 and a Coulter STKS counter and by phase contrast microscopy. With the Coulter T540 model PTP was most pronounced in blood samples anticoagulated with EDTA, Na-oxalate or Na-citrate. In the STKS counter EDTA, heparin and oxalate presented as the worst anticoagulants. The time course of platelet counts was significantly different between the two counters. Our results demonstrate that PTP is not restricted to EDTA, but is also present with other anticoagulants. In contrast, pseudoleucocytosis was observed only in EDTA-anticoagulated blood in the Coulter T540 device. We investigated the expression of platelet integrins and activation antigens on platelets of persons with anticoagulant-dependent PTP and in healthy controls without PTP. In the presence of EDTA the expression of GpIIb/IIIa was significantly reduced in the PTP subjects compared to control. Activation antigens CD62, CD63 and thrombospondin-antigen were upregulated in the presence of EDTA. These alterations in the expression of platelet antigens could also be induced on platelets of normal donors by incubation with sera of PTP subjects and EDTA.(ABSTRACT TRUNCATED AT 250 WORDS)

Anticoagulants↗
PubMed1995

Vaginal thrush and its management in pregnancy.

The frequency of vaginal thrush was determined in an unselected group of patients attending the antenatal clinic. Diagnosis was based on phase-contrast microscopy and culture. One hundred and two patients were initially included but only 98 completed this study. Thrush infection was detected in 25 (25%) patients. All 25 patients underwent treatment with one vaginal ovule containing 400 mg ketoconazole on each of three successive evenings. Thrush attack was eliminated in 23 (92%) cases. In view of the virtual absence of clinical symptoms, the recommendation to undertake general screening for thrush in pregnancy is discussed. The efficacy of treatment with ketoconazole ovules was studied and the results of treatment were reviewed after 4 and 8 weeks. Recurrence or re-infection has to be considered in pregnancy so that thrush treatment should sensibly be undertaken in the third trimester unless subjective symptoms indicate the need for earlier therapy.

Candidiasis, Vulvovaginal↗
PubMed1994

Effects of Sr-hydroxyapatite microcrystal on cultured cell.

Strontium-hydroxyapatite microcrystals (Sr-HAp sol) were produced by a wet method at room temperature with ultrasonic irradiation and were applied to MC3T3-E1, ROS, and L cells for periods of 2, 4, and 6 days in vitro. The effect on cell growth, the variation of LDH and Ca contents in the media, and attachment between cell and microcrystal were investigated. Sintered Sr-HAp and HAp sol were used as controls. A slight inhibitory effect of Sr-HAp sol on cell growth was found. The degree of inhibition was nearly the same as HAp sol. However, it was stronger than sintered Sr-HAp. The contents of LDH in the media increased with the degree of cell inhibition, and the contents of Ca in the media decreased from the initial stage of cell-sol contact. A good attachment of Sr-HAp sol to cultured cells was seen by phase-contrast microscopy and SEM.

Animals↗
PubMed1994

Normal human urothelial cells in vitro: proliferation and induction of stratification.

BACKGROUND: The purpose of the work was to establish urothelium as an in vitro model for the study of proliferation, stratification, and differentiation in "complex" epithelia. EXPERIMENTAL DESIGN: Normal human urothelial cells were cultured in a serum-free medium. The effects of epidermal growth factor (EGF), cholera toxin (CT), extracellular calcium and 13-cis-retinoic acid on cell growth, morphology, phenotype, and cytodifferentiation were studied using phase-contrast microscopy and indirect immunofluorescence. Stratification-related changes were additionally analyzed by transmission electron microscopy. RESULTS: Under optimized conditions, long-term cultures were successful in 44 (74.5%) out of 59 specimens. Bacterial infection was the most common cause of failure (9 cases). Primary urothelial cells required an initial plating density of > or = 10(4) cells/cm2 for survival; passaged cells survived much lower plating densities (> or = 2.5 x 10(2) cells/cm2). CT significantly improved cell attachment, but neither CT nor EGF were essential for growth. By contrast, cells failed to proliferate without bovine pituitary extract. In media containing bovine pituitary extract, CT, and EGF, cultures had a mean population doubling time of 14.7 +/- 1.8 hours, maintained a nonstratified phenotype, and expressed the cytokeratin (CK) profile of basal/intermediate urothelium: CK7, CK8, CK17, CK18 and CK19, with variable expression of CK13. CK20 was not expressed in vitro. CK14 and CK16 were also expressed, suggestive of squamous metaplasia in culture, which could be inhibited with 13-cis-retinoic acid. Increasing extracellular calcium from 0.09 to 0.9-4.0 mM slowed cell proliferation, induced stratification and desmosome formation, and increased expression of E-cadherin. High calcium, EGF, CT, and retinoic acid did not induce markers of late/terminal urothelial cytodifferentiation. CONCLUSIONS: We describe a simplified technique for the isolation and long-term culture of human urothelial cells. Urothelial cells in vitro are capable of rapid proliferation and can be induced to form integrated stratifying cell layers in high calcium medium. Stratification-related changes are not necessarily accompanied by urothelial cell maturation and differentiation.

Adolescent↗