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S Sugihara

Publications and source records attributed to S Sugihara.

At least 127 records · Page 7Linked to original sources
PubMed1991

Enzyme-induced aggregation and disaggregation of tumor cells via the cell surface glycocalyx in association with deoxyribonucleic acid.

Serine proteases cause aggregation of the rat ascites tumor cell lines AH-130, AH-109A and YS in vitro, and the tumor cell aggregates are dissolved by treatment with DNase I. We previously demonstrated that these events played a critical role in the augmentation or reduction of experimental blood-borne metastasis of these cell lines. In the present study, the ultrastructural features of this protease-dependent aggregation were analysed. Transmission and scanning electron microscopy revealed that after the protease treatment each tumor cell was surrounded by a thin membranous (sleeve-like) structure. This sleeve-like structure was stained with ruthenium red to an intensity similar to the cell surface of the control. Adjacent cells became attached to each other with microvilli via this fine structure. Immuno-electron microscopy revealed DNA antigen as dense patches on the sleeve-like structure or as faint and diffuse deposits on the outer surface of the cells by indirect immunoperoxidase staining using an anti-DNA monoclonal antibody. Both the sleeve-like structure and immunopositive deposits disappeared after treatment with DNase I. Neither cell viability nor the normal ultrastructure of their organelles was influenced by the enzyme treatment. These results indicate that serine protease-induced tumor cell aggregation is due to cellular contact via the sleeve-like structure, which probably originates from the cell surface glycocalyx in association with DNA molecules of unknown origin.

Animals↗
PubMed1991

[DNA ploidy in submucosal cancer of the stomach and its relationship to lymph node metastasis].

The relationship between DNA ploidy and lymph node metastasis was determined in 40 cases of gastric cancer confined to the submucosa (with lymph node metastasis 20 cases and without 20 cases). The DNA ploidy patterns were classified as follows: Type D, Type A1 and Type A2. Of the 20 cases with lymph node metastasis, 1 was Type D, 7 were Type A1 and 12 were Type A2. The likelihood of lymph node metastasis was 12.5% (1/8) for Type D, 43.8% (7/16) for Type A1 and 75.0% (12/16) for Type A2. It is concluded that although gastric cancer confined to the submucosa is classified as early one, analysis of DNA content places such tumors with lymph node metastasis into the advanced cancer category.

DNA, Neoplasm↗
PubMed1990

Intermediate filament expression in non-neoplastic pituitary cells.

Fifty-one non-neoplastic human pituitary glands, including examples with Crooke's hyalinization or amyloidosis, were examined by an immunoperoxidase method using antibodies to keratin, vimentin, neurofilaments (NFs), glial fibrillary acidic protein (GFAP), desmin, actin, S-100 protein and a variety of pituitary hormones. It was confirmed that most of the epithelial cells in the pituitary gland express keratin immunoreactivity. These cells included endocrine cells in the anterior lobe, endocrine cells and squamous metaplastic cells in the pars tuberalis, columnar and ciliated epithelia forming follicular structures and salivary-type epithelium in the pars intermedia, and anterior lobe cells infiltrating the posterior lobe. This study also demonstrated that keratin and NFs may be co-expressed in endocrine cells in the pituitary anterior lobe, that keratin, vimentin and GFAP may be co-expressed in the epithelial cells forming cyst-like follicle in the pars intermedia, and that vimentin and GFAP may be co-expressed in folliculo-stellate cells and pituicytes. In addition, the GFAP and S-100 protein-negative high columnar epithelium in the pars intermedia tended to be positive for adrenocorticotropic hormone and melanocyte stimulating hormone, while the low columnar epithelium with the co-expression of GFAP and S-100 protein was negative for pituitary hormones.

Amyloidosis↗
PubMed1990

Intermediate filament expression in pituitary adenomas.

Seventy-five formalin-fixed and 18 alcohol-fixed pituitary adenomas were studied immunohistochemically using antibodies to keratin, vimentin, neurofilaments (NFs), glial fibrillary acidic protein, desmin, actin, S-100 protein and a variety of pituitary hormones. The pituitary adenoma cells were positive for keratin, vimentin and NFs (68 kDa and 160 kDa) and in a few instances there was co-expression of these three types of intermediate filaments (IMFs). The pattern of keratin-specific staining showed diffuse cytoplasmic or patchy paranuclear reactivity and of NF- or vimentin-specific staining showed fibrillar or patchy paranuclear reactivity. The patchy staining seemed to decorate the fibrous body. There was no correlation between the distribution of IMFs and pituitary hormones in pituitary adenomas except that melanocyte-stimulating-hormone-positive reactivity was limited to the NF-positive adenomas. The pattern of IMF staining did not depend on hormone production in adenomas.

APUD Cells↗
PubMed1990

Serine protease-induced enhancement of blood-borne metastasis of rat ascites tumour cells and its prevention with deoxyribonuclease.

Serine proteases, such as alpha-chymotrypsin or elastase, caused an aggregation of rat ascites tumour cell lines, AH-130, AH-109A and YS, in a protein free medium which preserved the cell viability. This aggregation, which was monitored spectrophotometrically, was dependent upon the protease activities and was resistant to treatment with either a calcium chelating reagent (EDTA) or neuraminidase. However, the tumour cell aggregates were redispersed by treatment with deoxyribonuclease I (DNase I). This dispersal effect was dependent upon the DNase activity. A possible relationship between the tumour cell aggregation and development of blood-borne metastasis was studied. An intravenous inoculation in rats of tumour cell aggregates performed by the alpha-chymotrypsin treatment resulted in significantly higher numbers of lung metastatic foci than an injection of single cells. When the re-separated single cells, prepared in vitro by treatment with DNase I following alpha-chymotrypsin treatment, were injected instead of the aggregates, the enhancement of metastasis was reversed. These enhancement and reversal effects were mimicked in vivo by intravenous injections of protease and nuclease following inoculation of a single cell suspension. That is, the number of metastatic foci caused by single cell inoculation followed by an intravenous alpha-chymotrypsin injection, was higher than that in a control group receiving PBS instead of alpha-chymotrypsin. Again, this augmentation was reversed by an injection of DNase I following alpha-chymotrypsin injection. Furthermore, an injection of DNase I alone itself reduced the starting number of metastases resulting from injection of the single tumour cell suspension. These data suggest that the metastatic behaviour of tumour cells may be increased by protease inducible DNA dependent cell aggregation should it occur in the blood stream.

Animals↗
PubMed1990

Autoimmune thyroiditis induced in mice depleted of particular T cell subsets. III. Analysis of regulatory cells suppressing the induction of thyroiditis.

It has previously been demonstrated that T cell clones with potentials to induce autoimmune thyroiditis exist in lymphoid organs from normal healthy individuals. The present study investigates the nature of regulatory cells co-existing in a normal lymphoid cell population to prevent the activation of these thyroiditis-inducing T cells. T cell-depleted (C57BL/6 x C3H/He) F1 mice (B cell mice) were prepared by adult thymectomy and injection of anti-thymocyte serum, followed by lethal X-irradiation and bone marrow reconstitution. Typical thyroiditis was induced in these B cell mice by i.v. administration of Lyt-1dull T cells but not of whole T cells from normal syngeneic mice. Additional injection of normal thymocytes into B cell mice which had been transferred with the Lyt-1 dull T cells resulted in complete prevention of thyroiditis induction. Mature thymocytes were responsible for this regulatory function and such regulatory cell activity was also found in peripheral lymphoid cells such as spleen cells. These regulatory cells exerted their capacity to prevent thyroiditis in cell dose-dependent and injection timing-dependent manners; thyroiditis was prevented when they were injected in cell doses of greater than 1.5 x 10(7)/mouse and before the initiation of the thyroiditis lesion. Most interestingly, the phenotypes of regulatory cells were Thy-1+ and L3T4+. Since the thyroiditis-inducing Lyt-1 dull T cells has previously been shown to be of L3T4+, these results indicate that there exist functionally heterogeneous subsets in an L3T4+ T cell population and that some L3T4+ T cells function as regulatory cells to prevent the activation of thyroiditis-inducing L3T4+ T cells co-existing in the normal lymphoid cell population.

Animals↗
PubMed1990

T cell clones are killed by a thymic stromal cell monolayer following stimulation of T cell receptor with antigen and/or H-2 molecules on the monolayer.

A thymic stromal cell clone, MRL104.8a, expressed class I and class II H-2k antigens after exposure to gamma-interferon (gamma-IFN) and produced thymic stroma-derived T cell growth factor (TSTGF) irrespective of gamma-IFN exposure. Culturing the keyhole limpet hemocyanin (KLH)-specific, I-Ek-restricted 9-16 helper T cell (Th) clone on an Ia (I-Ak and I-Ek)-expressing MRL 104.8a monolayer induced potent proliferation of the 9-16 cells by virtue of the TSTGF produced by the monolayer. In contrast, the addition of KLH to cultures resulted in lethal growth inhibition of the 9-16 Th clone. Such a phenomenon was also observed for various Th as well as cytotoxic T lymphocyte (CTL) clones, and the following were revealed: (i) the growth of the ovalbumin (OVA)-or bovine thyroglobulin (BTg)-specific Th clone on the la-expressing MRL 104.8a monolayer was also inhibited by addition of the relevant antigen. The fact that these Th clones required antigen-presenting cells (APC) capable of processing antigen for the recognition of the respective target antigen suggested the potential of MRL 104.8a cells for antigen-processing; (ii) the lethal growth inhibition of KLH-specific, I-Ak (23-1-8)- or I-Ek (9-16)-restricted Th clone was prevented selectively by anti-I-Ak or anti-I-Ek antibody respectively; (iii) the I-Ek-alloreactive Th clone (2-13) was supported for its growth on a gamma-IFN-unexposed MRL 104.8a monolayer, whereas this clone was killed on an I-Ek-expressing monolayer; and (iv) when I-Ak-reactive CTL clones were cultured on an Ia- or Ia+ monolayer, CTL clones failed to exhibit cytotoxic effect on either the Ia- or the Ia+ monolayer, but were conversely killed by the Ia+ monolayer. Its killing was also prevented by an antibody which inhibits the recognition of Ia antigen on the monolayer by CTL clones.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

A case of liver cirrhosis with a hyperplastic nodular lesion.

A hyperplastic nodular lesion resembling focal nodular hyperplasia (FNH) was found in the cirrhotic liver of a 50-year-old male patient. A nodule was detected by ultrasonography and hepatic angiography conducted as part of a routine follow-up study for chronic liver disease, and was excised under a diagnosis of suspected hepatocellular carcinoma. Grossly, central stellate scar-like septa subdividing the nodule ware noted. These fibrous septa contained many small arteries and veins, as well as bile ducts. The parenchyma of the nodule also contained many small arteries. Although these findings were similar to those seen in typical FNH, the present lesion was different in that it was encapsulated, occurred against a background of liver cirrhosis, lacked hepatocyte hyperplasia and showed hemosiderin deposition.

Hemosiderin↗
PubMed1990

Eosinophilic granuloma of lymph node. A case report.

Eosinophilic granuloma confined to the lymph node of a 25-year-old Japanese woman is reported. She presented with a low-grade fever and pain in the left cervical region. A finger-tip-sized cervical lymph node was excised for histological study. Microscopically, the normal architecture of the lymph node was distorted, and histiocytoid cells had proliferated mainly in the sinus. Numerous eosinophils and an appreciable number of large multinucleated cells were also observed. Ultrastructurally, Birbeck granules were found in the cytoplasm of the histiocytoid cells. Immunohistochemically, the proliferating cells and multinucleated cells were found to be positive for S-100 protein but negative for lysozyme in the cytoplasm. The patient has been well without recurrence for 10 months after the lymph node biopsy.

Adult↗
PubMed1990

[Treatment of radioactive waste phenol with Fenton's oxidation].

A new procedure was developed for the waste treatment of radioactive phenol on a laboratory scale. Waste phenol was dissolved in water (2% as phenol), and ferrous ion (10 mg/l as Fe2+) was added. Hydrogen peroxide (6% as H2O2) was added separately in three steps, 20, 30, and 50% of the volume, in order to avoid rapid reaction. The solution was heated at 80-90 degrees C for several hours in a beaker covered with a watch glass till the color of the solution changes from red purple to pale yellow. Then, the solution was neutralized with sodium hydroxide and heated for 1 h to decompose excess hydrogen peroxide. When the procedure is carried out with four 2 l beakers on a hot plate, 100 ml of phenol (1,200 ml of the aqueous solution saturated with phenol) can be oxidized simultaneously.

Laboratories↗
PubMed1990

[Pathomorphologic study on early hepatocellular carcinoma (HCC)--a study of cell density in well-differentiated HCC of the early stage].

In order to clarify the histologic characteristics of well-differentiated hepatocellular carcinoma (HCC), a comparative morphometric study on cell density was performed in 15 HCCs smaller than 2 cm in diameter, 6 HCCs with marked fatty and/or clear cell change, 7 hyperplastic nodules, 5 hyperplastic nodules containing foci of HCC, and non-cancerous areas of the livers bearing small HCC. In well-differentiated HCC, marked increase of cell density accompanying by decrease of cell size and increase of nuclear cytoplasm ratio were prominent, and the cell density was approximately two times larger than that of the non-cancerous area in most cases. In HCCs with marked fatty and/or clear cell change, as an increase of cell density was not evident because of swelling of the cytoplasm due to fat and/or glycogen accumulation, it should be careful to differentiate them from non-cancerous nodular lesions including hyperplastic nodule with marked fatty change. Hyperplastic nodules could be divided into two groups; those with marked increase of cell density, and those without increase of cell density. In the former group, 5 of the 7 nodules contained cancerous foci.

Carcinoma, Hepatocellular↗
PubMed1990

[A case of brain metastasis from hepatocellular carcinoma].

Reported is the case of a patient who underwent surgical resection of a brain metastasis from a hepatocellular carcinoma. The 62-year-old male was admitted to hospital because of headaches and a left hemiparesis. Six years earlier he had undergone transcatheter arterial embolization for a hepatocellular carcinoma. Further, one year ago the lower lobe of his right lung had been resected because of a pulmonary metastasis from the same tumor. A neurological examination on admission revealed disorientation, dressing apraxia, and a left hemiparesis. A CT scan revealed two highly dense masses with peripheral low dense areas in the right temporoparietal region, which were heterogenously enhanced with a contrast medium. Right carotid angiogram showed tumor stains in the same region. Also, a magnetic resonance T1 weighted image showed highly intense masses, and a T2 weighted image showed low intensity masses with prominent brain edema. Thus, a right fronto-temporo-parietal craniotomy was performed, and the two masses were removed. Histological examination revealed hepatocellular carcinoma. The postoperative course was uneventful, and the left hemiparesis improved gradually, enabling the patient to walk without assistance. A brain metastasis from a hepatocellular carcinoma has been rarely reported in the literature since the survival period is very short due to rapid disease progression at the primary site, so that most reports have been based on postmortem examination. The MRI, CT, and the angiographic findings are included in this report.

Brain Neoplasms↗
PubMed1990

[Laboratory tests on cancer--cytology].

A comparative study was performed on needle aspiration cytology and the histological grading of 34 cases of small liver cancers. According to the Edmondson-Steiner's classification, 9 of the 34 cases were Grade I, 10 cases were a mixture of Grades I and II and 15 were Grade II or a mixture of Grades II and III or Grades I, II and III. The group consisting of Grade II and mixtures of Grades II and III or Grades I, Ii and III were diagnosed by needle aspiration cytology using cytological criteria described previously, but cases consisting of Grade I and mixtures of Grades I and II were very difficult to diagnose because of the relative lack of cellular atypia, and the diagnostic accuracy in this group was low. Retrospectively, ceLlularity, cellular architecture and the nuclear-cytoplasmic ratio were the most valuable cytological findings in the cases of Edmondson-Steiner's Grade I and the mixture of Grades I and II. In addition, some cases of small liver cancers had characteristically large lipid vacuoles which resembled a signet ring cell. Imprint cytology of neuroblastomas is a rapid diagnostic test which is very useful for differential diagnosis of neuroblastoma from other childhood solid tumors. Recently, flow cytometric DNA analysis and the N-myc oncogene have been proposed as important factors in the estimation of the prognosis of neuroblastomas. Three of fore patients with aneuploid DNA under the age of 1.5 years at diagnosis survive, while five of eight patients with diploid DNA over the age of 1.5 years at diagnosis died during a 12 to 120 month follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

Monoclonal antibodies to rat Kupffer cells. Anti-KCA-1 distinguishes Kupffer cells from other macrophages.

Two monoclonal antibodies, anti-KCA-1 and anti-KCA-2, directed against rat Kupffer cells (hepatic sinusoidal macrophages) were developed. Immunohistologic studies of the liver and analysis of isolated hepatic cells by immunofluorescence and flow cytometry showed that the reactivity of these antibodies was restricted to macrophages. Both KCA-1+ and KCA-2+ cells were located predominantly in the periportal region; in contrast, Ia+ sinusoidal cells were located primarily in the centrilobular region. Macrophagelike cells within the portal tracts expressed KCA-2 but not KCA-1. These findings indicate the presence of heterogeneity within the macrophage population of the liver. Anti-KCA-1 reactivity appeared to be almost entirely restricted to Kupffer cells; only a few macrophages in the thymus and a small number of cells in the bone marrow expressed KCA-1. In contrast, KCA-2 was more widely distributed; splenic, lymph node, and intestinal macrophages were intensely stained with anti-KCA-2. These studies indicate that KCA-1 is a marker of Kupffer cells.

Animals↗
PubMed1989

Hepatocellular carcinoma with sarcomatous change: a special reference to the relationship with anticancer therapy.

Among 579 autopsy cases of hepatocellular carcinoma (HCC), 55 cases (9.4%) exhibited a sarcomatous appearance. The incidence of HCC with a sarcomatous appearance has been increasing over the past 17 years. A sarcomatous appearance was found in 20 out of 335 autopsy cases of HCC (5.9%) during the 12 years from 1969 to 1980, and in 35 out of 244 autopsy cases of HCC (14.3%) during the last 6 years, when effective anticancer therapies, such as the one-shot injection of anticancer agents into the hepatic artery (one-shot therapy) and transcatheter arterial embolization (TAE), have become popular. A sarcomatous appearance was found in 20.9% of the cases undergoing anticancer therapy and in 4.2% of the cases not undergoing anticancer therapy. Among the various anticancer therapies, the sarcomatous appearance was most frequent (27.6%) in cases with repeated TAE. Thus, a close relationship between the sarcomatous appearance in HCC and anticancer therapies was suggested. Regarding the development of the sarcomatous appearance, we presume that it may be caused by the phenotypic change of HCC cells caused by anticancer therapy, or that a number of factors, including anticancer therapy, may accelerate the proliferation of the sarcomatous cells existing in the original tumor as one of the histological components. In order to clarify the true nature of sarcomatous lesions in HCC, further histological and biological studies are required.

Carcinoma, Hepatocellular↗
PubMed1989

Model for clonal elimination in the thymus.

A thymic stromal cell clone, MRL104.8a, expresses class I as well as class II H-2k antigens after exposure to gamma-interferon. This clone also produces thymic stroma-derived T-cell growth factor (TSTGF), which is distinct from other known interleukins and is capable of promoting the growth of various antigen-specific helper T cell (Th) clones without requiring a specific antigen or interleukin 2. When the keyhole limpet hemocyanin (KLH)-specific, I-Ek-restricted Th clone 9-16 was cultured on an Ia (I-Ak and I-Ek)-expressing MRL104.8a monolayer, potent proliferation of the 9-16 cells was induced by TSTGF produced by the monolayer. In contrast, the addition of KLH resulted in lethal growth inhibition of Th clone 9-16 cells. Another Th clone that is KLH-specific but I-Ab-restricted was capable of proliferating on the Iak-expressing MRL104.8a monolayer whether or not KLH was present. More importantly, death of Th clone 9-16 cells cultured on a MRL104.8a monolayer in the presence of KLH was almost completely prevented by the addition of anti-I-Ek or anti-CD3 monoclonal antibodies, which are capable of blocking antigen recognition by the T-cell receptor. However, when Th clone 9-16 cells were cultured in the presence of KLH but on a monolayer of MRL28.8a cells, another thymic stromal clone that expresses a comparable amount of I-Ek antigen but produces a marginal amount of TSTGF, cells did not die; a lethal effect was induced by adding TSTGF. These results indicate that the TSTGF-producing and Ia-expressing thymic stromal cells induce the continuous proliferation or selective elimination of each T-cell clone, depending on whether the T-cell receptor is stimulated by the relevant antigen associated with Ia molecules expressed on the stromal cell surface.

Animals↗