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T Atsuta

Publications and source records attributed to T Atsuta.

18 recordsLinked to original sources
PubMed2001

Production of monoclonal antibodies against mammalian Ring1B proteins.

The Polycomb group (PcG) genes play a role of transcriptional repressor for long-term maintenance of the Hox cluster gene expression. Recently two structurally similar gene products, Ring1A and Ring1B, were identified. Genetic evidence has indicated that Ring1A has Pc-G properties, however, Ring1B functions are still unknown. To gain functional insights for Ring1B, we raised the mouse monoclonal antibodies (MAbs) against murine Ring1B protein. Using these antibodies, we have detected specifically mouse, human and monkey Ring1B gene products from whole cell extracts in immunoblot and immunoprecipitation analyses. Immunofluorescent staining by the antibodies has shown that endogenous Ring1B proteins clearly co-localize with Ring1A at the pattern of diffuse nuclear speckles. Together with their sequence similarity, Ring1B also may function as a Pc-G protein. Finally, we have proposed that the anti-Ring1B would be useful for biochemical and cytological analyses of Ring1B and Pc-G complex.

Animals↗
PubMed1990

Presence and characterization of glycolipid sulfotransferase in human cancer serum.

Sulfotransferase, which catalyzes sulfation of the carbohydrate of galactosylceramide (GalCer) and is localised in the Golgi membrane of cells, was assayed for activity in human serum. To do this, an organic solvent was added to the incubated reaction mixture containing GalCer as an acceptor and phosphoadenosine phospho[35S]-sulfate as a donor of sulfate to dissociate the synthesized sulfolipid from serum protein. This was followed by isolation of the sulfolipid on an anion-exchange column. Through this procedure, human serum was found to contain sulfotransferase activity. The serum enzyme was activated by Mn2+. Km values of the enzyme for GalCer and 'active sulfate' were 4.6 microM and 5.2 microM, respectively. The enzyme activity was assayed in sera of cancer patients. The serum activity (mean +/- SE, 0.27 +/- 0.027 pmol.microliter-1.h-1) in renal cell carcinoma patients, whose activity has been demonstrated to be elevated, was significantly (P less than 0.005) increased compared to that of the normal control (mean +/- SE, 0.18 +/- 0.0014 pmol.microliter-1.h-1) and of other urological tumors examined.

Biomarkers, Tumor↗
PubMed1990

An autopsy case of triple cancers including signet-ring cell carcinoma of the breast--report of a rare case with reference to a review of the literature.

A 67 year old Japanese woman who had been suffering from general fatigue was diagnosed as having metastasis of signet-ring cell carcinoma of the bone marrow from a biopsied specimen. A clinical effortive search to the systemic organs revealed a tumor of 4 x 3 cm in size in the lower part of her left breast, which was subsequently diagnosed as the primary site histopathologically. The patient was immediately treated surgically, however, her general condition generally deteriorated and she expired 5 months after the operation. Autopsy revealed dissemination of tumor cells in the bone marrow, bilateral pleura, and soft tissue around the operated site. The autopsy additionally revealed squamous cell carcinoma of keratinizing type in the uterine cervix and well differentiated tubular adenocarcinoma in the gallbladder. A review of the literature revealed this case to be the first reported case of triple cancers including signet ring-cell carcinoma of the breast, proven by autopsy in Japan.

Adenocarcinoma↗
PubMed1990

An autopsy case of malignant fibrous histiocytoma of the mediastinum, presenting multiple metastases to the small intestine and to the brain--a rare case report with a review of the literature.

An autopsy case of malignant fibrous histiocytoma (MFH) of the mediastinum in a 25-year-old Japanese man is described. He initially complained of general fatigue and intermittent tarry stool, and was radiographically revealed to have a huge mass within the mediastinum as well as multiple nodules within the abdominal cavity, respectively. The mediastinal tumor could not be resected because of direct tumor invasion into surrounding tissues. Within the abdominal cavity, three distinct tumor nodules were discovered in the jejunum, which could be resected surgically. Histopathologically, the components of both lesions were very similar, and the present case was interpreted as multiple metastases of mediastinal MFH to the intestinal wall. In spite of various kinds of treatment, the mediastinal tumor rapidly enlarged, causing SVC syndrome. Brain CT findings suggested multiple metastases which were considered to be the cause of death. Autopsy confirmed that the main tumor nodule was located within the mediastinum, with brain metastases. The present case of mediastinal MFH is considered to be the youngest case as well as the first case presenting intestinal metastases.

Adult↗
PubMed1990

A case of coexisting malignant carcinoid tumor and adenocarcinoma in the papilla of Vater.

A 47-year-old Japanese woman in whom obstructive jaundice had already been diagnosed, was found to have a dome-shaped elevated tumor approximately 3 cm in diameter located in the area very close to the papilla of Vater on endoscopical and radiographical investigations. Histopathologically, the resected tumor was composed mainly of solid nests of atypical argyrophilic cells, and partially of an area of well differentiated tubular adenocarcinoma, showing mutual transition in the mucosal layer. Both immunohistochemical and ultrastructural analyses confirmed the difference in character of tumor cells between these two areas: neuroendocrine cell carcinoma and tubular adenocarcinoma of common type in the intestine. To the best of our knowledge, this is only the third case reported to be a coexisting malignant carcinoid tumor and adenocarcinoma arising in the periampullary region.

Adenocarcinoma↗
PubMed1987

[A rare autopsy involving primary squamous cell carcinoma of the breast showing a very rapid and aggressive clinical course].

A rare autopsy case of a primary squamous cell carcinoma of the breast is reported. A 74-year-old Japanese woman, suffering from a left axillary nodule, underwent a radical mastectomy in May, 1986. The histopathological diagnosis had revealed a primary squamous cell carcinoma of the breast with a small area that indicated a solid tubular carcinoma. The patient, however, died four months later after a very rapid and aggressive metastasis of the tumor cells to her various organs. The autopsy revealed the presence of metastatic tumor cells in the systemic organs including the heart, lungs, liver, spleen, kidneys, pancreas, the bone marrow, and in the whole gastrointestinal tract. Histopathologically, the metastatic tumor cells in these organs were composed of squamous cell carcinoma solely, without tubular formation, showing a remarkable keratinization and mitotic activity. The histogenesis and the nature of the squamous cell carcinoma of the breast are briefly discussed.

Aged↗
PubMed1985

Wetting characteristics and blood clotting on surfaces of copoly(gamma-Benzyl-L-glutamate, gamma-hydroxyethyl-L-glutamine).

The film surface of poly(gamma-benzyl-L-glutamate) (PBLG) was modified with 2-aminoethanol to enhance its hydrophilicity. Controlling the reaction conditions of PBLG and 2-aminoethanol, various types of copoly(gamma-benzyl-L-glutamate, gamma-hydroxyethyl-L-glutamine) film surfaces were obtained. Surface free energy (gamma sv), the dispersive component of gamma sv (gamma dsv), the nondispersive component of gamma sv (gamma psv), and the interfacial free energy of polymer surface with water (gamma sw), which were obtained by using the contact angle measurement and calculation method proposed by Andrade et al., were changed remarkably by the aminolysis. The gamma sv value increased after 2 h of aminolysis from 48.2 (PBLG) to 65.3 dyn/cm and gradually increased to around 70 dyn/cm after 12 h reaction. (gamma dsv) and (gamma psv) changed from 31.0 and 17.2 dyn/cm (PBLG) to 26.5 and 44.3 dyn/cm, respectively. These parameters of the material surfaces, modified over 12 h reaction, were found to be similar to those of the surfaces of canine aorta, vein, and human fibrin membrane. Blood clotting times on these polymer surfaces were comparatively longer than on siliconized glass surfaces.

Blood Coagulation↗
PubMed1977

Glycosaminoglycans in human lung carcinoma.

The glycosaminoglycans were prepared by exhaustive Pronase digestion and alkaline treatment of squamous cell carcinoma and adenocarcinoma tissues of human lung, and of tissues taken at a site distant from the tumor as a control. The glycosaminoglycan classes were characterized by chemical enzymic, and electrophoretic methods. The presence of oversulfated chondroitin-and/or dermatan-sulfates which have not up till now been found in lung tissues was also demonstrated in carcinoma and control tissues, their contents being higher in the carcinoma tissues. The levels of whole glycosaminoglycans were markedly increased in carcinoma tissue. The classes of glycosaminoglycans which increased in lung carcinoma tissue were predominatly chondroitin-4-and/or-6-sulfates and hyauronic acid.

Adenocarcinoma↗
PubMed1976

Effects of uridine nucleotides and nucleotide pyrophosphatase on glycolipid alpha and beta-N-acetylgalactosaminyltransferase activities in guinea pig microsomes.

Membrane-bound alpha and beta-N-acetylgalactosaminyltransferases (EC 2.4.1.0) which catalyze formation of non-reducing terminal linkages of Forssman hapten and globoside, respectively, could be differentiated with respect to the different effects of UDP on the two enzyme activities. UDP markedly inhibited the alpha-transferase activity, in contrast to its stimulatory action on the beta-transferase. These effects of UDP were similar to those of UDPglucose, which was demonstrated to be a competitive inhibitor (Ki, 3.3 - 10(-5) M for UDP-N-acetylgalactosamine) for the alpha-transferase reaction. Other uridine derivatives tested suppressed both the transferase activities, being more inhibitory for the alpha-transferase than for the beta-transferase. Under the synthetic conditions of these aminoglycolipids, UDP-N-acetylgalactosamine as a donor was simultaneously degraded into N-acetylgalactosamine-1-phosphate and finally into N-acetylgalactosamine by UDP-N-acetylgalactosamine pyrophosphatase, which is part of the membrane system. UDPglucose was confirmed as being able to prevent the enzymatic hydrolysis of UDP-N-acetylgalactosamine. UDPglucose, therefore, acts to suppress both the alpha-N-acetylgalactosaminyltransferase (but not the beta-transferase) and the pyrophosphatase activities. The inhibitory effect of UDPglucose on the alpha-transferase activity was most probably due to its direct action on the transferase rather than its function in protecting UDP-N-acetylgalactosamine donor from pyrophosphatase action.

Animals↗
PubMed1975

Alterations of glycolipid glycosyltrasnferase levels in lymphoma and lymphoid tissues of lymphoma-bearing hamsters.

Thymus from lymphoma-bearing hamsters in advanced stages of tumor growth showed enhanced activities of four glycolipid-glycosyltransferases which lead to the step-wise synthesis of lactosylceramide to Forssman hapten. The alpha-galactosyltransferase activity of the thymus was decreased until day 6 of inoculation but increased thereafter. The activities of all the transferases tested were significantly lowered in lymphoma tissue. The level of UDP-galactose pyrophosphatase did not correlate with the transferase activities.

Animals↗
PubMedDate not supplied

Early clinical results of the modified human umbilical cord vein homograft (Dardik Biograft).

Fifty-six reconstructions using Biograft were performed in 45 cases with peripheral arterial occlusion. These consisted of 11 femoro-popliteal bypasses above the knee, 19 femoro-popliteal below the knee, 10 femoro-tibial or peroneal and 16 other miscellaneous procedures including aorto-femoral and extra-anatomic bypasses. Overall patency rates for each type of procedure were 81.8%, 78.9%, 30.0%, and 93.8%, respectively. The cumulative patency rate (calculated by the life table method) for the total group was 70.5% at 56 months. Early failure was thought to relate to technical factors in most instances. The majority of late failures was due to intimal hyperplasia at the distal anastomotic site. One of 9 late failures was successfully treated by patch angioplasty at 23 months following initial operation. Therefore, in order to attain better late results, early discovery of developing stenosis by noninvasive examination techniques and arteriography is important.

Aged↗