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At least 37 records · Page 2Linked to original sources
PubMed1976

Functional characteristics of the intraspinal spread of viscerosomatic activity.

The functional characteristics of the intraspinal spread of the dual-component viscerosomatic reflex response were studied in chloralose-anaesthetized cats. In the region of the direct inputs of splanchnic afferents into the spinal cord, the initial part of the early (propriospinal) component is evoked by afflux from the extraspinal pathway in the sympathetic chain and has the shortest latent period. At segment Th8 to Th12 level this was 5.2--8.1 msec; cranially and caudally from this level it was longer. Activity spreading from the adjacent segments via intraspinal longitudinal systems also participates in the origin and course of the early component of the efferent discharge. The rate of ascending intraspinal irradiation in the thoracic region was 3.2--12 m/sec (6.6 +/- 2.4 m/sec). The rate of the descending spread of propriospinal activity in the thoracic region via intraspinal pathways was 3.6--18.3 m/sec (12.5 +/- 4.5 m/sec); in the lumbar region it was significantly lower -- 2.9--19.3 m/sec (7 +/- 4.5 m/sec). The latent period of the later component varied from 20 to 30 msec and displayed a cranio-caudal increase in length. The rate of the descending spread of the later component in the thoracic and lumbar cord did not differ significantly (20 +/- 10 m/sec and 22 +/- 13 m/sec respectively). The continuous splanchnic discharge in the lumbosacral region is correlated to the different rate of the intraspinal spread of the early and the late response and to their overlapping.

Animals↗
PubMed1979

[Dynamics of the spreading of normal and transformed hamster cells].

Morphological peculiarities of spreading studied by scanning electron microscopy in two lines of transformed hamster fibroblasts (HETR and HEC--40) were compared to the normal hamster embryo fibroblasts (NHG). The surface of spherical not streading cells was of a mixed type microrelief (small blebs and microvilli). In transformed cells, the microvillous component was more developed than in their normal counterparts. During cell spreading distinct differences were observed between normal and transformed cells in their cell surface contact interaction with solid substratum. NHF cells formed a well-developed concentrically disposed thin lamelloplasm, while HEC-40 cells had asimmetrically disposed lamelloplasm in combination with long filopodia and HETR cells had a rather thick lamelloplasm consisting of several fragments (often forming star-like pattern). At the polarization stage of spreading neither HETR nor HEC-40 reached the same degree of spreading and flattening as NHF. Moreover, the dorsal surface of transformed cells had a complex microrelief in contrast to a rather smooth surface of NHF. These results are discussed in connection with earlier results on spreading of normal and transformed mouse fibroblasts.

Animals↗
PubMedDate not supplied

[Cinematics of fibroblast spreading. I. Analysis of a population].

Normal mouse fibroblasts were studied by means of time-lapse microcinematography under phase-contrast microscope. For 31 cells the area measurements during spreading were made with the intervals of 2.5--5 minutes. The following results have been obtained. The maximal area of spreaded cell is 3--4 times greater than the surface area of the sphere with the spherical cell radius. There is a tendency of the cell area to increase linearly in the middle, that is in a regime of a constant middle rate. Most cells spread either in one regime, or in two, when a more rapid regime is followed by a shower one. The change of the spreading regime is a result of the control of mean rate of spreading.

Animals↗
PubMed1977

[Effect of colcemid on the radial spreading of fibroblasts in culture].

Effect of colcemide upon the spreading of mouse embryo fibroblast-like cells on the substrate was studied with the aid of time-lapse microcinematography and scanning electron microscopy. On the glass, colcemide did not prevent the transition of cells into a well-attached state, however, the time needed for this transition was seen considerably increased as compared with the control cultures. Intermediate stages of spreading on flat glass had the following abnormal features in colcemide-containing medium: a) shapes of cytoplasmic outgrowths formed by the cell were altered and their distribution along the cell border appeared less regular; b) partial detachments of the attached parts of cells occurred very frequently; c) the spreading of various parts of the cells was not correlated. Possible mechanisms of colcemide action on the cell spreading are discussed, and it is suggested that intracellular structures sensitive to colcemide are essential for coordination of reactions that occur in various parts of the cell in the course of spreading.

Animals↗
PubMed1978

Effects of prostaglandins on the spreading, adhesion and migration of mouse peritoneal macrophages.

The effects of prostaglandins on the in vitro properties of mouse peritoneal macrophages namely spreading, adhesion and migration were investigated. PGE1 and PGE2 inhibit the spreading and adhesion of complete Freund's Adjuvant induced peritoneal macrophages significantly at concentrations of 1 ng per ml and above whereas they enhance the migration of these cells at concentrations of 100 ng per ml and above. PGA2 and PGB2 are less potent as they inhibit spreading and adhesion only at a concentration of 1 microgram per ml. At his concentration PGB2 enhances migration whereas PG2 has no effect. PGF 2alpha has no effect on the spreading, adhesion and migration of macrophages in the concentration range of 0.1 ng to 1,000 ng per ml.

Animals↗
PubMed1978

Attachment and spreading of baby hamster kidney cells to collagen substrata: effects of cold-insoluble globulin.

Studies have been carried out to determine the effects of cold-insoluble globulin (CIG) on the attachment and spreading of baby hamster kidney cells on various collagen substrata. Cell attachment to native collagen substrata occurred in the absence of CIG just as fast as attachment to dried collagen or gelatin substrata occurred in the presence of CIG. On the other hand, cell attachment to dried collagen or gelatin was markedly reduced in the absence of CIG. Cell spreading also occurred on native collagen in the absence of CIG; however, CIG was absolutely required for cell spreading to occur on dried collagen or gelatin. Finally, anti-CIG antiserum or lactoperoxidase treatment inhibited cell spreading on CIG-coated substrata but not on native collagen substrata. The data are discussed in terms of the interaction of fibroblasts with collagen in situ.

Cell Adhesion↗
PubMed1976

Viral spread in the presence of neutralizing antibody: mechanisms of persistence in foamy virus infection.

Several viruses were categorized on the basis of their ability to spread from cell to contiguous cell and form plaques in the presence of antiviral antibody. Herpes simplex virus, cytomegalovirus, and vaccinia, measles, and foamy viruses were able to spread in the presence of neutralizing antibody, whereas coxsackievirus, encephalomyocarditis virus, vesicular stomatitis virus, mumps virus, and simian virus 5 failed to spread. A detailed study of one of these virus groups (simian foamy viruses) suggested that the ability of these viruses to spread from cell to cell in the presence of antiviral antibody, the failure of antiviral antibody and complement to lyse infected cells, and the poor induction and relative resistance of these viruses to the antiviral action of interferon contribute to the persistent nature of this infection.

Antibodies, Viral↗
PubMed1979

Retrograde spread of hydrocortisone containing foam given intrarectally in ulcerative colitis.

A method is described of estimating retrograde spread through the colon of a 10% hydrocortisone acetate foam by labelling the foam with technetium-99m sulphur colloid and observing spread after intrarectal administration by serial gamma-camera pictures. The recommended 51 ml dose of foam reached the mid-sigmoid colon in all of the nine patients who had active ulcerative colitis. Furthermore, in seven the foam reached the proximal sigmoid colon. Foam spread less extensively in five patients with quiescent disease than in those with active disease. Increasing the volume of enema to 50 ml did not improve retrograde spread through the colon. These results suggest that 10% hydrocortisone foam may be useful in treating patients with distal ulcerative colitis that is not necessarily limited to the rectum.

Administration, Topical↗
PubMed1979

Mechanisms of cellular adhesion. IV. Role of serum glycoproteins in fibroblast spreading on glass.

We have investigated the exogenous factors required for the transition from the round shape of suspended fibroblasts to the characteristic spread shape on serum-coated glass. Following the evidence of others that the transition is facilitated by adsorbed component(s) related to CIG/LETS (cold-insoluble globulin/large external transformation-sensitive) proteins, we have isolated 2 such preparations from chick serum. Their influence has been investigated on fibroblast adhesion, spreading and growth and they have been characterized by gel electrophoresis, immunological cross-reactivity, amino acid and carbohydrate residue analysis, sedimentation velocity behaviour and circular dichroism spectroscopy. The preparations have molecular weights of 225/215,000 and 140,000 Daltons respectively and are closely similar in composition and secondary structure. The 225/215 000 Dalton doublet is probably a product of limited proteolysis which almost certainly occurred in the avian circulation. For cells seeded on glass precoated in different ways and in different supplemented media we could detect no change in the extent of attachment but there were profound influences on cell shape following this initial adhesion. We confirm that prior adsorption of either CIG-related preparation to glass does indeed promote fibroblast spreading in the absence of other serum components and that CIG is the sole serum component with this type of activity. We now add 2 important qualifications: (i) the presence of substrate-adsorbed serum CIG is not essential for spreading when other serum components are present in the medium; and (ii) the adhesive organization shown by interference reflexion microscopy is incompletely formed unless the additional serum components are present in the medium. We therefore conclude that 16C fibroblasts have the ability when given the stimulus of soluble serum components other than CIG, but not otherwise, to synthesize all the components necessary for the highly organized contacts with glass, including endogenous CIG/LETS proteins.

Amino Acids↗
PubMed1979

Inhomogeneous spread of excitation in canine Purkinje fibers.

Spread of excitation in isolated canine bundle branches was examined by microelectrode technique in order to investigate the possibility of dissociated impulse transmission in normal Purkinje fibers. In all experiments, local excitation of the preparation evoked either by fine bipolar extracellular electrodes or an intracellular microelectrode proceeded much faster along the longitudinal axis of the fibers than along the transverse axis. As a result, the spread of excitation in the vicinity of stimulating site showed significantly inhomogeneous character. The inhomogeneity of excitation spread became more manifest with more eccentric location of the stimulating site in a given preparation. Larger preparation showed greater degree of inhomogeneity. Nevertheless, the inhomogeneous spread of excitation alone appeared unlikely to provide multiply pathways which were functionally dissociated with each other. When premature stimulation was applied, however, different conductivity among fibers within a single false tendon was oberved, suggesting that each conducting element became more independent.

Animals↗
PubMed2026

DNA-FISH Metaphase Spreads to Distinguish Extrachromosomal DNA from Homogeneously Staining Regions in Human Cancer Cell Lines.

Whole-genome sequencing identifies focal DNA amplifications with base-pair resolution but cannot determine whether amplified sequences reside on extrachromosomal DNA (ecDNA, also known as double minutes) or within chromosomally integrated homogeneously staining regions (HSRs). DNA fluorescence in situ hybridization (DNA-FISH) metaphase spreads remain the gold standard for distinguishing these amplification states at single-cell resolution. Here, we present a detailed protocol for DNA-FISH metaphase spreads using human cancer cell lines, encompassing cell culture, metaphase arrest, hypotonic treatment, fixation, chromosome spreading, fluorescent probe hybridization, and fluorescence imaging. The protocol incorporates intermediate quality-control steps to verify successful chromosome dispersion and optimize metaphase spread quality, making the workflow accessible to laboratories without specialized cytogenetics expertise. Results demonstrate clear visualization of ecDNA and HSR amplification states using locus-specific probes and illustrate common technical artifacts that can affect interpretation. This protocol provides a robust and reproducible approach for studying the structural organization of oncogene amplification in cancer cells.

Humans↗
PubMed1977

Inhibition of surface immunoglobulin centeral capping of Daudi cells and cell spreading of HeLa-S3 cells by neocarzinostatin.

The effects of an antitumor antibiotic, neocarzinostatin (NCS), on the surface immunoglobulin central capping induced by anti-immunoglobulin M antibody on Daudi cells and on the cell spreading of trypsinized HeLa-S3 cells were examined. Pretreatment of Daudi cells and HeLa-S3 cells with NCS, 5 to 30 micrograms/ml, for 4 hr inhibited cap formation and cell spreading, respectively. It was shown that there is a direct relationship between the dose and the degree of inhibition. Inhibitors of DNA synthesis such as bleomycin, mitomycin C, and 1-beta-D-arabinofuranosylcytosine showed no inhibitory effect on cap formation or cell spreading. However, known microtubule-acting agents such as colchicine and vinblastine sulfate completely inhibited both capping and cell spreading at a dose of 10 micrograms/ml. In view of the fact that 10 micorograms NCS per ml also inhibit the formation of microtubular paracrystals induced by vinblastine sulfate in HeLa-S3 cells and that other agents known to influence microtubule function such as local anesthetics and calcium ionophores also inhibit both paracrystal formation and cap formation, these new observations add further support to our hypothesis that NCS affects microtubular proteins transmembranously in vivo.

Anesthetics, Local↗
PubMed1979

Tumor cell aggregation and mode of cancer spread in linitis plastica type of gastric carcinoma.

Spread of tumor cells in linitis plastica type of gastric carcinoma was studied in relation to features of tumor cell aggregation which were classified into two types: free-cell type and small nest type. Free-cell type was accompanied by a larger amount of fibrous stroma in submucosal layers than in small nest type. In the gastric wall lymphatics and regional lymph nodes, small nest types was more prominent than the free-cell type. Lymphatic permeation was noted predominantly in the submucosa. In the mucosa, both free-cell and small nest types were frequently present. In carcinoma with free-cell type predominance, diffuse infiltration with infrequent lymphogenous spread was noted, while in carcinoma with small nest type predominance, spread via the lymphogenous route was observed more frequently. The mode of cancer spread in this type of carcinoma appeared to be affected by the type of tumor cell aggregation dominant in the mucosa.

Adenocarcinoma, Scirrhous↗
PubMed1979

Specificity of the macrophage spreading test with reference to Leishmania antigens and correlation with delayed hypersensitivity.

The inhibition of the macrophage spreading test, claimed to be an in vitro correlate of delayed hypersensitivity, was examined in guinea-pigs immunized with L. enriettii and L. tropica soluble antigens. Cells from peritoneal washings of the guinea-pigs were tested in presence of the homologous and heterologous antigens and also without antigen. Inhibition of macrophage spreading compared to control preparations was noted only in the presence of the homologous antigen when the skin test response of the donor animal was relatively small. The degree of inhibition decreased as the skin test volume increased and when skin test volumes were large there was actual stimulation of macrophage spreading, rather than inhibition. The addition of heterologous antigen to the peritoneal cell preparation always resulted in the augmentation of macrophage spreading above control levels. The possible mechanisms of this in vitro technique and its use as a taxonomic or diagnostic tool are discussed.

Animals↗
PubMed1979

[The spreading of Agrobacterium strains in soft-agar (author's transl)].

In a diluted synthetic medium solidified by 0.17% agar populations of Agrobacterium spread with a velocity of 0 to 20 mm/24 hours. This spreading is a consequence of chemotactic movement and cell division. Different bacterial strains spread with a characteristic velocity each. Loss of the TI-plasmid leaves the spreading behaviour unimpaired. It is changed after the introduction of virulence by Kerr transfer or after prolonged culture in D-amino acids.

Agar↗
PubMed1977

Plasma membrane vesiculation: correlation between macrophage spreading and the shedding of cell surface vesicles.

The data presented in this paper establish a correlation between the extent of macrophage spreading and the ability of macrophages to shed plasma membrane vesicles following incubation in a membrane vesiculant. Maximal macrophage spreading was observed following incubation in buffers containing Mn2+ or dithiothreitol. Scanning electron microscopy showed that such macrophages have a uniformly flat surface morphology. Exposure of these macrophage monolayers to a vesiculant containing 25 mM formaldehyde-2 mM dithiothreitol induced plasma membrane vesiculation. Scanning electron microscopy further demonstrated that vesicles were formed and released randomly over the cell surface and that vesicles varied in size from 1 to 15 micrometer. diameter. A variety of chemicals that share the common ability to bind to free sulfhydryl groups have been shown to act as membrane vesiculants as a result of their apparent ability to induce a unique form of cell injury which results in the shedding of cell surface vesicles. The differential effect of vesiculants on cells grown in suspension and as monolayer is interpreted to suggest that reorganization of the cellular cytoskeleton associated with cell spreading may underlie the ability of membrane vesiculants to induce plasma membrane vesiculation in highly spread and adherent macrophage monolayers.

Animals↗
PubMedDate not supplied

[Inflammation and host resistance against tumours. II. -- Antagonism between bradykinin and a fraction isolated from the supernatant of cultured malignant cells on the spreading of macrophages (author's transl)].

When murine peritoneal macrophages are incubated in presence of 10(-6) to 10(-8) M of bradykinin, their spreading is increased. When macrophages are incubated in presence of a low molecular weight fraction of the supernatant from cultured Lewis carcinoma's cells (AP) their spreading is decreased. When macrophages are incuated first with bradykinin and later on with AP, no inhibition of spreading is observed. When macrophages are incubated first with AP and later on with bradykinin, the increase of spreading is not observed.

Bradykinin↗
PubMed1977

Spreading depression analysis of contact behaviour of rats.

Social contact behaviour induced by spreading cortical depression was studied in rats. The controls looked for and remained in contact, whereas between the rats with spreading cortical depression and their other partners there was no contact. This phenomenon is due mainly to the absence of an active urge for contact. The contact behaviour of rats is evidently controlled by the cerebral cortex or by subcortical areas of the brain which are inhibited after the elicitation of spreading depression. The experiments show that the contact behaviour of rats has at least two components - an active urge for contact and passive tolerance of contact.

Amphetamine↗