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PubMed1990

In vitro pharmacologic separation of corneal endothelial migration and spreading responses.

Repair of corneal endothelial wounds involves two forms of cell translocation: (1) "migration," in which individual cells at the wound edge break contacts with neighboring cells and move as individuals into the wound defect, and (2) "spreading," in which cells within the confluent monolayer adjacent to the wound move as a group into the wound area. The authors combined morphometric analysis of Giemsa-stained cultures, phase-contrast video microscopy, and Rh-phalloidin staining of actin filaments to study the effects of epidermal growth factor (EGF) and indomethacin on the migratory and spreading responses to wounding using an in vitro wound-closure model which mimics the amitotic state and general behavior of human corneal endothelium. They found that EGF stimulated the migration of individual cells from the wound edge, induced cellular elongation, and promoted a diffuse distribution of actin filaments. Indomethacin promoted spreading of the confluent monolayer into the wound defect, induced enlargement and flattening of cells, and promoted the formation of long, thick actin stress fibers. These results provide evidence that the migration and spreading responses of corneal endothelial cells to wounding can be pharmacologically separated. The findings suggest that migration of individual cells during wound repair may result from an endogenous form of EGF-like stimulation and that the elongated shape associated with this form of translocation results, at least in part, from an EGF-like alteration in actin-filament organization. Spreading of the confluent monolayer to cover the wound defect may result from a decrease in cyclic adenosine monophosphate induced by a transient reduction in prostaglandin E2 synthesis. This form of translocation may result, in part, from enlargement and flattening of corneal endothelial cells secondary to an enhancement of actin stress-fiber formation.

Actins↗
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↗
PubMed1990

[Study of conservative treatment of breast cancer in view of the spread of primary lesion].

Two hundred and six patients with breast cancer t1 or t2 were subclassified histologically into the following 8 types; comedo type, papillary type, mucous type, papillotubular or cribriform type, small solid alveolar type, large solid alveolar type, sclerotic type and pure scirrhous type. The risk of remaining cancer with lumpectomy was investigated clinicopathologically in relation to intraductal spread and lymphatic invasion of cancer cells. The tumor invasion was classified into intraductal type, localized type or extraductal spreading type, and lymphatic invasion was divided into 2 grades, i.e., vicinity of the tumor and 5mm or more distant. 1. In cases of intraductal spread, the comedo type was the most frequent, followed by the papillary type and mucous type. 2. The small solid alveolar type accounted for the highest proportion, 22.7%, in the group with distant lymphatic invasion. 3. The incidence of lymph node metastasis was as high as 63.6% and 61.7% for the small solid alveolar type and pure scirrhous type. 4. In cases of intraductal spread, t1 accounted for 32.6% and t2 for 47.0%. 5. The incidence of positive lymph node metastasis was 28.9% for t1 and 52.0% for t2. Tumors associated with a higher risk of remaining cancer are those of the comedo type and papillary type in terms of intraductal spread, those of the small solid alveolar type and pure scirrhous type in terms of lymphatic invasion, and those measuring 2cm or more.

Breast↗
PubMedDate not supplied

[The production of spread synaptonemal complexes of meiocytes from animals and plants by a drying method].

A spreading technique was used to prepare synaptonemal complexes from animals (Bombyx mori and Mus musculus spermatocytes) and plants (Zea mays microsporocytes). Suspension of hypotonically treated cells was spread over plastic-coated slides and air-dried. Fixed and phosphotungsten acid-stained spread preparations were studied by phase-contrast and electron microscopes. The spreading-through-drying method is more efficient and thereby more preferable as compared to the classical hypophase spreading technique.

Animals↗
PubMed1989

[The role of thrombocyte prostanoids and products secreted by dense granules in the platelet attachment, spreading and aggregation on collagen substrates].

The role of platelet prostanoids and substances released from dense bodies (ADP and serotonin) in the initial attachment, spreading and aggregation of platelets on surfaces coated with I, III, IV and V genetic types of collagen was investigated. A positive linear correlation was found to exist between thrombi-like aggregate formation on collagen substrates and platelet prostanoid synthesis. No correlation was established between platelet aggregate formation and 14C-serotonin release. The cyclooxygenase inhibitor indomethacin and the antagonists of PG endoperoxides and TXA2 (13-APA and BM 13.177) completely block thrombi-like aggregate formation. Neither 13-APA nor BM 13.177 affect platelet spreading, while indomethacin inhibits this process by 25%. The ADP-scavenger CP/CPK inhibits platelet aggregation and spreading by 25-30%. The inhibitors of cyclooxygenase and CP/CPK do not influence the initial attachment of platelets. The data obtained suggest that thrombi-like aggregate formation on collagen substrates is mediated by the synthesis of PG endoperoxides and TXA2; however, in platelet spreading this synthesis plays a limited role. Spreading and aggregation of platelets on collagen substrates is only partly mediated by ADP and serotonin. Initial attachment of platelets does not depend on ADP and serotonin release and PG endoperoxide/TXA2 synthesis.

Adenosine Diphosphate↗
PubMed1989

[Fibroblast spreading in the presence of cytochalasin D: immunoelectron microscopy of the cytoskeleton].

Spreading of mouse embryo fibroblasts in the presence of cytochalasin D (1 microgram/ml) was studied using scanning electron microscopy, immunofluorescence, and electron microscopy of platinum replicas. Whereas circular lamellae were formed around the cell body during normal spreading, separate processes appeared at the cell periphery during spreading in cytochalasin-containing medium. The processes gradually elongated and branched. Cytoskeletons of fibroblasts spreading in the cytochalasin-containing medium were obtained by Triton X-100 extraction. They contained microtubules, intermediate filaments, actin "paracrystals" looking like short microfilament bundles, and patches of a meshwork-granular material. Immunogold coating of the cytoskeletons with anti-actin antibody showed that some meshwork-granular patches were decorated with gold particles, whereas the others were not. Non-actin patches were usually located on the distal ends of the processes, thus leaving behind the actin cytoskeletal components during the process growth. Another characteristic feature of this unidentified material is its usual association with the substratum and microtubules. These results suggest that the process protrusion during cell spreading in cytochalasin-containing medium may occur not due to actin polymerization as in the control cells, but due to involvement of some other non-actin cytoskeletal components. These components seem to be able to move along microtubules and to bind to the substratum.

Animals↗
PubMed1989

[Studies of the mechanisms of spreading of epileptic discharges in the central nervous system].

The process of spreading of epileptic discharges in central nervous system has to be discussed in two points of view; as a propagation of signals in neuronal networks and as a process of dynamics changes in neuronal circuits and nets. On the base of the spreading of afterdischarges between entorhinal cortex and both hippocampi we discussed time and space relations in spreading of epileptic discharges, and automatic analytical methods in localization of epileptic focus. Spreading epileptic discharge is not only the symptom of pathologic function of system but it simultaneously changes the dynamics of system in which it spreads and causes epileptic destabilization of neuronal circuits and nets. The above mechanisms after theoretical investigations play also important role in evaluation of secondary epileptic foci and posttraumatic epilepsy.

Cerebral Cortex↗
PubMed1988

Macrophage spreading disparity: alveolar vs peritoneal.

Macrophage spreading over glass surfaces is a recognized in vitro manifestation of activation. We examined macrophage spreading using a simplified assay. Hartley guinea pigs (n = 15) were anesthetized with pentobarbital (0.4 mg/gm) IM. Macrophages were obtained by lavaging the peritoneal (PM) and alveolar (AM) spaces with sterile 0.9% NaCl (NS). AM or PM (150,000 cells) were placed into chambers of Lab-Tek microtiter slides +/- phorbol myristate acetate (PMA). Slides were incubated /37 degrees C in 5% CO2 for 20 minutes. Macrophages with a diameter greater than 2 x control cells were considered spread. Compared to PM, resident AM show increased spontaneous spreading (16 +/- 2% vs 79 +/- 2%) respectively. AM demonstrated no significant concentration-dependent response to PMA stimulation. The PM has served as the basis for much of the morphological and functional observations attributed to macrophages in general. The above spreading data support the concept of disparity of macrophage function dependent upon various factors, including site of origin. Our observations suggest that extrapolation of macrophage characteristics to cells from discordant sources may not be possible.

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↗
PubMed1987

[Clinicohistopathological and immunohistochemical studies on intrapancreatic spread of pancreatic carcinoma].

Clinicohistopathological and immunohistochemical studies on intrapancreatic spread of pancreatic carcinoma were performed on 30 cases with total pancreatectomy accompanied by portal vein resection. In the observation of HE stained tissue sections of 25 cases of carcinoma of head of the pancreas, the intrapancreatic spread from the head to body or tail was observed in 9 out of 25 cases (36%). However, by the immunostaining of CEA, CA19-9 and Dupan 2, small cancer nests surrounded by fibrous tissues could be easily detected and intrapancreatic continuous spread from the head to body or tail was observed in 15 out of 25 cases (60%). The intrapancreatic spread of the carcinoma correlated with portal invasion of carcinoma, hardness of the body and tail, obstruction of main pancreatic duct and irregular pancreaticogram. The intraoperative quick immunostaining on the cryostat sections of the pancreatic tissue, together with the HE staining, is useful to determine the intrapancreatic spread of the carcinoma. The indication of total pancreatectomy for pancreatic carcinoma can be determined by these results.

Antigens, Neoplasm↗
PubMed1987

Tumor promoter and fibronectin induce actin stress fibers and focal adhesion sites in spreading human erythroleukemia (HEL) cells.

The effects of plasma fibronectin (pFn) and the tumor promoter 12-0-tetradecanoyl-phorbol-13-acetate (TPA) on adhesion and cytoskeletal organization of human erythroleukemia (HEL) cells were studied. HEL cells, that normally grow in suspension, attached rapidly on pFn-coated growth substratum and some cells showed spreading. Upon exposure to TPA most of the cells adhered and showed some degree of spreading also when plated on plastic. The spread cells showed mostly peripheral accumulations of F-actin in addition to actin fibers seen in some of the cells. When the cells were plated in the presence of TPA on pFn or on pFn-fragments, containing the cell binding site, all the cells adhered rapidly, spread extensively, organized prominent F-actin stress fibers and typical ventral plaques of vinculin and alpha-actinin. Both proteins were revealed also in the suspended cells by Western blot analysis. When plated on substratum coated with other pFn-fragments or laminin, the HEL cells did not adhere or spread. Both adhesion on pFn as well as formation of stress fibers in the presence of TPA could be prevented by the synthetic peptide Arg-Gly-Asp-Ser (RGDS). HEL cells were also able to organize typical ventral fibrillar arrays of Fn. Immunostaining and metabolic labeling experiments showed that the cells did not contain or synthesize Fn, indicating that the plaques were formed from exogenous pFn by the cells. The results suggest that Fn and TPA synergistically induce the organization of the actomyosin system in HEL cells by promoting the formation of prominent actin stress fibers and focal adhesion sites.

Actins↗
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↗
PubMed1982

[Various methods of spread of bladder tumours (author's transl)].

The authors undertake a complete review of the literature concerning the various methods of spread of bladder tumours. They successively consider spread through the thickness of the bladder wall, surface extension, direct implantation of exfoliated cells, lymphatic spread, and venous dissemination both in the bladder wall as well as to the viscera by metastases. It is difficult to give a brief analysis of such an exhaustive review. However, a number of facts are worthy of emphasis: --the frequency of invasion of the seminal vesicles and the prostate; --the reliability of combined clinical, radiological and endoscopic findings, which may be used to differentiate deep tumours and superficial tumours in more than 80% of cases; --the importance of methods which await development, such as the scanner and, above all, ultrasound techniques; --the importance of study of the vesical mucosa at a distance from the tumour itself, both by fluorescent cystoscopic methods, as well as by distant biopsies (30 to 50% of premalignant cell changes found in cystoscopically normal zones); --the frequency if invasion of the terminal portions of the ureters (10% on average) and of the urethra (12 to 15%); --the prognostic gravity of tumour emboli in the intraparietal lymph vessels, the presence of which reduces the chances of cure at 5 years by two thirds; --the usual limitation of the first lymph node spread to the external iliac and hypogastric vessels with the exception of tumours of the bladder neck, where the first lymph node spread occurs to the aortic bifurcation; --the gravity of the presence of emboli in the parietal veins which reduces chances of survival at 5 years by half; --finally, the recently recognized frequency of secondary bone tumours; --and the supposed frequency of infraclinical metastases which would be a considerable argument in favour of complementary chemotherapy in therapeutic protocol for carcinomas of the bladder.

Humans↗
PubMed1997

[The use of high resolution MR imaging for pre-treatment evaluation of breast cancer: detection of intraductal spread].

Thirty-two patients were examined in order to evaluate the role of high-resolution MRI in the treatment planning of breast cancer. A 1.5T Signa imager (GE Medical Systems) was used with dedicated receive-only breast coil. The pulse sequence based on RARE was used with the fat-suppression technique. After examining both breasts with larger FOV (30 cm), the affected breast alone was examined with smaller FOV (18 cm) and larger matrix (512 x 384) with Gd enhancement. Breast cancer showed more prominent and earlier enhancement compared with normal breast tissue. Linear or spotty continuous enhancement from the main tumor was considered to be suggestive of intraductal spread. Of 32 patients, 20 showed linear or spotty enhancement around the main tumor on MRI, and 15 of these 20 had intraductal spread. On the other hand, 12 out of 32 patients were considered to have little intraductal spread on MRI, and these findings corresponded to the pathological findings. Sensitivity, specificity and accuracy of detecting intraductal spread were 88%, 75% and 78%, respectively. In order to evaluate the extent of intraductal spread, further study using more precise correlation with pathology is necessary. High-resolution MRI was also considered to be useful for evaluating the presence of multifocal or multicentric focies or muscle invasion.

Adenocarcinoma↗
PubMed1998

[Pagetoid spread of intratubular germ cell neoplasia into rete testis forming tumor-like mass].

Intratubular germ cell neoplasia (ITGCN) is the preinvasive phase of testicular germ cell tumors. ITGCN can spread into the rete testis in a pagetoid manner, but there are very few published data about this phenomenon. Furthermore, the tumor-like mass formed by ITGCN with pagetoid spread into the rete testis has not been documented to date, and the present case is the first to be reported. A tumor-like mass was found close to the superior pole of the left testis in a 39-year-old male and was unrelated to the epididymis. Three other nodules of seminoma surrounded by fibroconnective tissue existed next to the mass. Histological sections revealed ITGCN which was characterized by the presence of large and polygonal germ cells exhibiting clear cytoplasm with distinct cell borders. The cytoplasm was rich in glycogen and the cell membrane was immunohistochemically positive for placental alkaline phosphatase. The nuclei had less coarse chromatin than that of seminoma. ITGCN cells spread in between the lining epithelium of the rete and the basement membrane. This characteristic spread was consistent with pagetoid spread into the rete testis.

Adult↗
PubMed1998

[Radiologic assessment of transpyloric spread of gastric carcinoma].

PURPOSE: We report on our personal experience with the radiologic and CT demonstration of the traspyloric duodenal spread of gastric carcinoma, whose relative frequency and prognostic value are recent literature data. MATERIAL AND METHODS: In the last 4 years we submitted to double contrast studies of the upper gastrointestinal (GI) tract 49 gastric carcinoma patients with antrum involvement. Twenty-one cases were staged with CT performed with gastric water distension, pharmacological hypotonia and dynamic contrast agent perfusion. Finally, 41 patients underwent surgical treatment. RESULTS: Radiologic evidence of transpyloric gastric carcinoma spread was found in 6 cases; CT, performed in 5 of them, was always in agreement. Five of 6 positive cases had surgical confirmation while one lesion was unresectable. No radiologic or CT false negatives were found among the remaining 36 surgical patients. Barium studies showed irregular antral lumen narrowing, rigid, open and eccentric pyloric channel, duodenal bulb deformity and irregular thickening. CT demonstrated antrum infiltration along the two gastric curvatures and the tumor spread to the duodenal cap. CONCLUSION: Antral cancer transpyloric spread is more frequent than previously reported and its presence should not exclude a carcinomatous process. Double contrast barium studies are a valuable tool in the demonstration of this spread, showing good correlation with CT staging findings.

Adult↗
PubMed1998

A mathematical analysis of the spread of HIV/AIDS in Japan.

The spread of HIV/AIDS in Japan was analysed using a mathematical model incorporating pair formations between adults and sexual contacts with commercial sex workers. The parameters involved in the model were carefully specified as realistically as possible to the actual situation in Japan. Plausible ranges were assigned to those parameters for which values are not known precisely. The model was used to simulate the effect of HIV infected commercial sex workers introduced into a population without HIV. It was shown that the model could generate different scenarios, an explosive infection or a temporal spread, according to different settings of the parameters. Then the condition for occasional introduction of HIV infected commercial sex workers to be able to cause an explosive spread of HIV infection was analysed. This condition was summarized in terms of the critical transmission probability so that we could easily evaluate the degree of the risk. For some unclear parameters, sensitivity to the critical transmission probability was calculated. We also calculated a plausible range of the critical transmission probability using the Latin hypercube sampling method where the parameters were distributed on the plausible ranges. According to the analyses of the model it is concluded that the actual situation of HIV spread in Japan should lie very near the critical point that determines whether the explosive HIV spread actually takes place. This also suggests that effective action taken immediately could be useful to prevent explosive HIV infection in Japan.

Adolescent↗
PubMed1996

Eicosanoids and nitric oxide influence induction of reactive gliosis from spreading depression in microglia but not astrocytes.

Microglia and astrocytes are transformed into reactive glia (RG) by brain disease and normal function. Eicosanoids and nitric oxide (NO), two intercellular mediators, may influence gliosis. We investigated how drugs that alter production of these paracrine signals effect induction of glial reactivity from spreading depression. Unilateral (left) neocortical spreading depression was induced in 95 halothane anesthetized rats by intracortical injections of 0.5 M KCl, with or without drug treatment (five animals/group). Immunohistochemical staining (IS) intensity using the OX-42 and anti-glial fibrillary acidic protein (GFAP) antibodies determined reactivity in microglia and astrocytes, respectively. After 3 days, brains were processed for OX-42 and GFAP-IS and mean optical densities (OD) of IS were measured. Average OD's (for OX-42) and the log ratio (left/right) of OD's (OX-42 and GFAP) were compared to normal animals. Spreading depression induced significant log ratios for both OX-42- and GFAP-IS (P's < 0.01). However, dexamethasone (a glucocorticoid), nordihydroguaiaretic acid (a lipoxygenase inhibitor), and nitroprusside (a NO donor) prevented significant left sided and log ratio OD values for microglia (P's > 0.05). L-Name, a NO synthase inhibitor, caused significant increases in left and right OD's for microglia (P's < 0.05). Mepacrine, a phospholipase A2 inhibitor, Indomethacin, a cyclooxygenase inhibitor, and phenylephrine, an adrenergic agonist, did not prevent induction of significant OX-42 log ratios (P's < 0.01, 0.05, 0.01), and resulted in increases in left side OD's (P's < 0.01, 0.05, 0.05). Significant GFAP log ratios occurred after spreading depression in all drug groups, P's < 0.01. Thus, induction of reactivity in microglia is more sensitive to eicosanoids and NO than in astrocytes.

Animals↗