Search PubMed⌕ Search

Biomedical subjects

G Asano

Publications and source records attributed to G Asano.

At least 127 records · Page 7Linked to original sources
PubMed1992

Production of macrophage colony-stimulating factor by adult murine parenchymal liver cells (hepatocytes).

The activity of macrophage colony-stimulating factor (M-CSF) was found in the culture supernatant of mouse parenchymal liver cell fractions in a bone marrow colony-forming assay. The activity of an M-CSF-like substance purified by a four-step procedure was neutralized by goat anti-mouse M-CSF antiserum. M-CSF mRNA was detected in cellular RNA prepared from cultured parenchymal liver cell fractions by Northern blot analysis and also in cultured parenchymal liver cells by in situ hybridization. These results indicate that parenchymal liver cells have the capacity to produce M-CSF. We discuss the role of M-CSF in hematopoiesis, the immune response, and other biological phenomena.

Acrylic Resins↗
PubMed1992

Evaluation of elastic structural change in coronary atherosclerosis using scanning acoustic microscopy.

Coronary atherosclerotic lesions were observed by scanning acoustic microscopy (SAM), a technique which can visualize regions of differing elasticity. Three regions, i.e., dark (dR), intermediate (iR) and bright (bR) demonstrating differences in acoustic reflection intensity and the velocity of surface acoustic waves, were seen in the lesions. Furthermore, lipid-positive areas were found to be dR and iR and fatty crystalline areas were observed only in iR regions by polarizing microscope. These phase transitions of fat affected the acoustic properties in each region. According to SAM images, intimal structural changes were classified into three types, minimum structural change (type I), the overcrowded net-like dR structure (type II) and markedly disturbed structure with a decrease of dR (type III). The medial structure change was also classified into three types paralleling the decrease of dR (types M1, M2 and M3). Intimal type II with a large degree of thickening and intimal type III with medial type M3 were highly prominent in the acute myocardial infarction (AMI) group (P less than 0.01). Therefore these results suggest that the anisotropic elasticity induced by micro-elastic changes in the arterial wall may be associated with functional disturbance of the vascular wall.

Acoustics↗
PubMed1992

[Vascular proliferation in the stroma of gastric cancer and its significance].

To elucidate vascular characteristics in the stroma of gastric cancer, the morphological and immunohistochemical changes of vascular components were examined in 27 gastric cancers and 7 noncancer gastric tissues including 2 peptic ulcers. In differentiated adenocarcinoma, a large number of blood vessels were observed in vicinity of the cancer glands and type IV collagen (C-IV) was localized around the blood vessels and cancer glands, and ultrastructurally, cytoplasmic organelle and weibel-Palade bodies were encountered in the endothelium. In poorly differentiated adenocarcinoma, a small number of blood vessels were distributed sporadically in the stroma and there were vascular endothelia in which von Willebrand factor (VWF) was localized, and there were much more endothelia in which VWF was not localized compared with differentiated adenocarcinoma. C-IV was localized only around the blood vessels and OKM5 was localized in the endothelia which were distributed in the center of cancer nest in poorly differentiated adenocarcinoma. Ultrastructurally, there were not so many Weibel-Palade bodies in the endothelia without complete basement membrane. The morphological and functional changes of blood vessels were correlated with cancer differentiation and metastasis. These changes may provide biological feature of cancer and may be induced by cancer cells, vascular endothelia and mesenchymal cells.

Adenocarcinoma↗
PubMed1991

Localization of acidic and basic fibroblast growth factor mRNA in human brain tumors.

Acidic and basic fibroblast growth factors (aFGF and bFGF) are closely related peptide mitogens acting on both mesoderm- and neuroectoderm-derived cells, including fibroblasts, endothelial cells and glial cells. In order to identify the expression of mRNAs for these growth factors, in situ hybridization using human aFGF and bFGF RNA probes was performed in 24 human brain tumors. The mRNAs for aFGF and bFGF were expressed in the cells of various tumors (1/1 and 1/1 astrocytoma, 2/2 and 2/2 anaplastic astrocytomas, 6/6 and 6/6 glioblastomas, 4/4 and 4/4 meningiomas, 3/3 and 3/3 schwannomas, 1/2 and 1/2 pituitary adenomas, 4/4 and 4/4 metastatic carcinomas, 0/1 an 0/1 hemangioblastoma, 0/1 and 0/1 craniopharyngioma) and were also detected in endothelial cells and surrounding neuronal cells of brain tumors. These results suggest the possibilities that aFGF and bFGF contribute to the uncontrolled growth of tumor cells and the proliferation of endothelial cells in autocrine and paracrine manners, and that the expression of mRNAs for these growth factors in the surrounding neuronal cells results in enhancement of tumor growth.

Adolescent↗
PubMed1991

[The role of stromal components and Ca++ ATPase in pleomorphic adenoma and adenoid cystic carcinoma].

In order to clarify the neoplastic-mesenchymal cell interaction, tumor structures were histologically classified into duct, solid and scattered types, and stromal changes were observed in each type with histochemical techniques. The quantitative and qualitative differences of the stromal components as proteoglycan and collagen were histochemically differed in these morphological features. Ca++ ATPase was ultrastructurally localized on the plasma membrane of myoepithelial cell in salivary glands. The activity of Ca++ ATPase changes in tumor cell differentiation of pleomorphic adenoma and adenoid cystic carcinoma. These results suggest that the stromal components and Ca++ ATPase play an important role on the tumor cell proliferation and differentiation in these tumors.

Adenoma, Pleomorphic↗
PubMed1991

[An autopsy case of cardiomyopathy combined with nephrotic syndrome and pulmonary cytomegalic inclusion disease].

A 63-year-old male complained of palpitation and dyspnea. ECG showed paroxysmal supraventricular tachycardia. Echocardiogram revealed asymmetrical thickening of the cardiac septum, and by other clinico-pathological observations, nephrotic syndrome and colon adenoma were detected. For these diseases, steroid therapy and operation were performed, respectively. Ten months later, chest X-ray revealed diffuse abnormal shadow in the bilateral lung fields, and the patient expired due to respiratory distress syndrome. The patient's heart weighted 300g and showed extensive myofibril disarray in bilateral ventricles involving the septal region of the heart. Degeneration and atrophy of the atrioventricular node was seen. In the lungs, organizing pneumonia, old pleuritis, diffuse septal fibrosis and cytomegalovirus infection were demonstrated in the alveolar walls. Kidneys showed slightly sclelotic changes in glomeruli and edema-fibrosis in the interstitium. In this rare case, hypertrophic cardiomyopathy was combined with nephrotic syndrome due to glomerular change, and colon adenoma. The patient died of cytomegalovirus infection in the lungs. The histogenesis of myofibril disarray was discussed in these diseases.

Cardiomyopathy, Hypertrophic↗
PubMed1990

Changes in serum and tissue carcinoembryonic antigen with growth of a human gastric cancer xenograft in nude mice.

We established a human gastric cancer xenograft which, when inoculated into nude mice, showed a positive correlation between tumor growth and the serum level of carcinoembryonic antigen (CEA). Serum CEA levels in the mice rose continuously with increasing tumor weight after inoculation, showing a correlation coefficient of 0.96. A positive correlation was also observed between the tissue CEA level and tumor weight, the former increasing along with the latter. Furthermore, the level of serum CEA closely paralleled that of tissue CEA. The serum CEA level fell after tumor extirpation, with a half-life of approximately 86 h. These results suggest that the elevation of serum CEA is attributable to the gain in tumor weight as well as the increase of CEA production in the tumor tissue. Thus, human gastric cancer xenografts in nude mice are a good model for examining the biological role of CEA.

Adenocarcinoma↗
PubMed1990

Immunohistopathological properties of pleomorphic adenoma in salivary gland.

Fifty-eight salivary gland pleomorphic adenomas and 5 normal salivary glands were studied immunohistochemically with respect to intermediate filaments (keratin, desmin, and vimentin), actin and S-100 protein to observe the cellular differentiation of these tumor cells. Normal myoepithelial cells showed positive immunostaining for actin, vimentin and S-100 protein. Pleomorphic adenomas expressed keratin, vimentin and S-100 protein to various degrees, but only a few tumor cells of pleomorphic adenoma revealed actin. The results indicate that the tumor cells of pleomorphic adenoma show a bipolar differentiation capability of both epithelial and mesenchymal origins, although normal myoepithelial cells show only mesenchymal characteristics. The findings also support previous reports using light and electron microscopy, and also contribute to more precise diagnosis and a better understanding of the histogenesis of this tumor.

Actins↗
PubMed1990

Caroli's disease associated with liver cirrhosis. An autopsy case.

Caroli's disease is one of the rare congenital conditions associated with the cystic dilatation of intrahepatic bile ducts. This is a case report of a 41-year-old Japanese male who complained of jaundice and general fatigue at the age of 34 for the first time. He was clinically diagnosed as having Caroli's disease by physical examination and image analyses study. The patient died after seven years and three months from the onset of the disease on account of renal function impairment. An autopsy was performed, revealing cystic dilatation of the intrahepatic bile duct, associated with a cirrhotic liver and also evidence of portal hypertension, substantiated by esophageal varices and splenomegaly. The liver weighed approximately 2,200 g. A histological investigation revealed typical morphological evidence of cirrhotic glomerulopathy and tubular degeneration with the presence of calcium casts in the dilated tubuli. The lung revealed diffuse alveolar damage with partial organization associated with remarkable polymorphonuclear and macrophagic infiltration. In this paper, the pathogenesis of the cirrhotic change, biliary duct abnormality and potential malignant transformation in the liver are discussed in relation to Caroli's disease.

Adult↗
PubMed1990

[Experimental study on the cytoskeletal alteration of hepatocytes in obstructive jaundice with special reference to the significance of the localization of the intracellular filaments].

The effects of common bile duct ligation on hepatocytes in rats were investigated by light and electron microscopical techniques. Cytoskeletal elements such as actin and cytokeratin were immunohistochemically increased in liver cells after bile duct ligation. Electron microscopical observation revealed that bile canaliculi were rich in microvilli in the control liver, while in the experimental rats, the bile canaliculi were dilated. A decreased number of microvilli and bleb formations were also noted. In the cytoplasm, pericanalicular microfilaments and intermediate filaments were abundant. These findings suggest that increased biliary pressure may affect not only the hepatocellular plasma membrane constituents, but also the filamentous structure in the hepatocyte. Furthermore the congested bile acid affect may be worse after a common bile duct obstruction.

Actin Cytoskeleton↗
PubMed1990

Immunohistochemical localization of Na+, K(+)-ATPase and calmodulin in rat myocardium.

The immunohistochemical localization of Na+, K(+)-ATPase and calmodulin was investigated in rat heart muscle using antiserum against the catalytic subunit of the human kidney Na+, K(+)-ATPase and bovine testis calmodulin at the electron microscopic level. Immunostaining for both Na+, K(+)-ATPase and calmodulin was noted on the plasma membrane and plasmalemmal vesicles of the vascular endothelium and cardiac muscle cells. Calmodulin was also detected in the cytoplasm. These immunohistochemical localizations were evaluated by immunoblot analyses. Such localization of Na+, K(+)-ATPase and calmodulin suggests that they may play an important role in the regulation of Na(+)-Ca++ exchange across the cell membrane.

Animals↗
PubMed1990

[An ultrastructural investigation of changes in hypoxia in the subependymal layer of the newborn rabbit].

Fetal and neonatal hypoxia is suggested as a noticeable risk factor related to the occurrence of subependymal hemorrhages. To investigate the cause of newborn subependymal hemorrhages, a 0 day old newborn rabbit was exposed to either 5 or 10 minutes hypoxia by N2 box. After exposure, the brain was observed by optical and electric microscope using horseradish peroxidase (HRP) as the protein tracer to study the change in the capillary permeability. The result obtained were as follows: 1) In the newborn rabbit blood gas analysis, PO2 (mmHg) decreased more in the 5 and 10 min hypoxia groups than the control group which used the N2 box. pH and BE changes were similar to PO2 (mmHg). On the other hand, PCO2 (mmHg) increased proportionately. These results indicated that this hypoxic method changed blood gas and caused acidosis. 2) In the optical microscopic examination, the 0 day old newborn rabbit brain was found to have a thin subependymal layer. We could not find obvious subependymal hemorrhage using optical microscope. 3) In the electric microscopic examination, HRP was found in the cavity of the brain capillary at the subependymal layer and was slightly incorporated into the pinocytic vesicle of the lumen on the control. Since the tight junction filled the roll out, HRP was not found outside the capillary. 4) The 5 min hypoxia group caused astrocyte foot swelling, edema and slight opening of the tight opening of the tight junction. HRP was passed through the tight junction, but not outside the capillary. 5) The 10 min hypoxia group caused destruction of astrocyte and edema around the capillary. The tight junction was more opened than in the 5 min hypoxia group and HRP leaked out of the capillary through the tight junction. From the findings mentioned above, it is suggested that our hypoxic model increased permeability of the capillary in subependymal layers and that this change might be the first ultrastructural change before the onset of subependymal hemorrhages.

Animals↗
PubMed1990

[A hepatocellular carcinoma showing sarcomatous features and an extensive metastasis].

A 47-year-old female was admitted for a right hypochondrial pain and was diagnosed as having a hepatic tumor with a cystic lesion. After a right and a caudal lobectomy, she died of hepatic failure due to a tumoral recurrence. At autopsy, a cystic tumoral nodule, 15 x 7 cm in size, and numerous other nodules were revealed in the liver. Metastases were seen in both lungs, the left kidney, the colon, the mesenterium, the peritoneum, the diaphragm, and the para-pancreatic lymph nodes. The hepatic tumors consisted of four types of tumor cells: spindle, round, mixed (spindle and round cells), and cells with pseudoalveolar features. All tumor cells showed a positive immunohistochemical reaction to polyclonal keratin, low molecular monoclonal keratin, alpha 1 anti-trypsin, vimentin and to actin in their cytoplasms. This is considered a very rare case.

Actins↗
PubMed1990

[Immunohistochemical study on epidermal growth factor and its receptor in human pancreatic carcinoma].

We investigated immunohistochemical expressions of the epidermal growth factor (EGF) and the epidermal growth factor receptor (EGFR) in 25 cases of pancreatic carcinoma, including 13 cases of metastatic lymph nodes. EGF and EGFR were stained mainly in the cytoplasm and on the surface of some pancreatic carcinoma cells, with positive rates of 18/25 (72%) and 9/25 (36%) respectively. In all cases EGFR was noted only when EGF was also detected. EGF and EGFR were stained frequently in differentiated types. In metastatic lymph nodes, EGF and EGFR were found in 54% and 15% respectively, and they were detected only when they were also noted in the same patient's primary lesions. EGF and EGFR were found more frequently in Stages III and IV than in Stage II. These results emphasize that EGF and EGFR may promote both the proliferation and the differentiation of human pancreatic carcinoma cells, as in other sites.

Adult↗
PubMed1990

[Liver regeneration and immune system--morphological and cytochemical studies of activated spleen cells during the liver regeneration after partial hepatectomy].

Morphological and cytochemical changes were investigated in spleen cells after 70% hepatectomy in mice. During liver regeneration after the hepatectomy, the spleen weight gradually rose to a peak at 6 day. In the spleen, the number of POD-positive myelocytic cells and NCAE-positive granulocytic cells also reached a peak 4 days after the operation and then decreased. On the other hand, ANBE-positive monocytic cells gradually increased up to 9 day and didn't decrease for this period. On day 9 of the culture, the boundary between the red and the white pulps of the spleen became unclear. In this spleen, the clusters of blast cells were sporadically observed. Splenic T cells cocultured with nonparenchymal adherent normal liver cell or nonparenchymal adherent normal liver cell supernatant developed into granulocyte colonies in earlier periods and monocyte colonies in later periods. These findings suggest that the factors released from liver cells may regulate strictly spleen cell activation. Blast cell formation in the culture with nonparenchymal adherent normal liver cell supernatant was amplified by anti interferon (alpha + beta) antibody. These facts indicate that the functional network of cytokines is formed by the interaction of various cytokines (IL-1, IL-6, CSF, IFN, etc.) in nonparenchymal adherent normal liver cell supernatant.

Animals↗
PubMed1989

Contrasting actions of estradiol on the growth of human gastric cancer xenografts in nude mice.

The effects of estradiol on the growth of six human gastric xenografts in nude mice were studied and diverse effects were found, including one case of stimulation, two of inhibition and three of unchanged condition. Neither the histological features of the original tumor nor the estrogen-binding capacity seemed to be related to the response to estradiol. It is concluded that the growth of human gastric cancer can be modulated by estradiol.

Animals↗