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H Nakada

Publications and source records attributed to H Nakada.

At least 55 records · Page 3Linked to original sources
PubMed1996

Ampullary somatostatinoma in a patient with von Recklinghausen's disease.

We report a case of somatostatinoma of the ampulla of Vater associated with von Recklinghausen's disease in a 44-year-old woman. On admission the patient was jaundiced, and percutaneous Cholangio-drainage was performed. Cholangiography revealed stenosis of the common bile duct at the lower end Duodenoscopy showed a yellowish tumor of the ampulla of Vater, and the biopsy specimens showed no malignant cells. Pylorus-preserving pancreaticoduo-denectomy was performed. Histologically, the tumor was composed of small round cells with a solid or trabecular pattern and with multiple psammoma bodies. Immunohistochemical examination showed that the tumor cells stained for somatostatin. Genomic examination showed neither K-ras nor p53 gene mutations of the resected specimen.

Adult↗
PubMed1995

Ultrastructural changes of secretory cells of salamander lingual salivary glands under varying conditions.

BACKGROUND: In general the ultrastructure of secretory cells can be modified under secretory stimulated and non-stimulated conditions. The ultrastructure of the lingual salivary glands of hibernating salamanders in the natural environment was examined and compared to those of fasted and fed animals kept in the laboratory. METHODS: Hibernating salamanders of the species Hynobius tokyoensis were collected from the natural environment during the winter breeding season and sacrificed for this study. One group was sacrificed immediately, another group was kept under fasted condition, and another group was regularly fed; both of the latter groups were kept at room temperature for 1 month and then sacrificed. The tongue was fixed for electron microscopy and processed by conventional method, and semithin sections were histochemically examined for glycoconjugates. RESULTS: The lingual salivary glands of this salamander species were composed of simple or often branched tubular glands opening onto the dorsal surface of the tongue. The secretory cells which composed their terminal portions were all columnar in morphology and histochemically mucous in nature. Under hibernation or prolonged fasting at room temperature, the mucous granules of these columnar secretory cells were decreased in number and the Golgi apparatus appeared inactive. A conspicuous structural peculiarity was multiple fingerprint-like structures of the rough-surfaced endoplasmic reticulum (RER). Most of these membranes were composed of stacks of tightly packed cisternae. Under regular feeding, the mucous granules were closely packed in the cytoplasm of the secretory cells and the basal nucleus was slightly enlarged. The Golgi apparatus showed progressive activation with distended saccules. The unique membranous arrangement of the RER which was observed in the fasting animals was completely absent, and the cisternae were irregular in width with considerable variation of the intercisternal spaces. CONCLUSIONS: The tongue of the salamander H. tokyoensis has numerous tubular salivary glands which are mucous in nature. The architecture of the organelles in the secretory cells is subject to modification in response to the cellular metabolism.

Animals↗
PubMed1995

Expression of the T antigen on a T-lymphoid cell line, supT1.

We have measured glycosyltransferase activities of SupT1 cells, a T-lymphoid cell line shown to react with autoantibodies in the sera of many HIV patients. Since considerable alpha-N-acetylgalactosaminyl-transferase and beta 1, 3 galactosyltransferase activities were found in SupT1 cells, at least the O-glycan core 1 structure can probably be synthesized. FACS analysis using an anti-T monoclonal antibody showed expression of the T antigen (Gal beta 1-3 GalNAc). Glycoproteins with the T antigen were isolated by immunoprecipitation with the anti-T antibody from a SupT1 cell lysate labelled metabolically with 3H-glucosamine and then analysed by SDS-PAGE. It was revealed that the precipitate contained a glycoprotein with a molecular weight corresponding to that of leukosialin. O-glycans were prepared from the immunoprecipitate by alkaline-borohydride treatment and then fractionated on Bio-Gel P-2, GalNAcOH and Gal-GalNAcOH being identified inter alia. These results suggest that an anti-T antibody may be included in the autoantibodies found in HIV-1 infected individuals.

Antigens, CD↗
PubMed1995

Distribution of Tn antigen recognized by an anti-Tn monoclonal antibody (MLS128) in normal and malignant tissues of the digestive tract.

Alterations in the normal glycosylation process are often associated with oncogenic transformation. Using an anti-Tn monoclonal antibody, MLS128, we have investigated the immunohistochemical localization of Tn antigen in normal and malignant tissues of the digestive tract. In normal tissues, MLS128 was immunoreactive with the squamous epithelium of the esophagus and was weakly reactive with the columnar epithelia of the stomach, duodenum, colon, bile duct and pancreatic duct. In malignant tissues, positive immunostaining was detected with high frequency (75%-100%) in carcinomas of the esophagus, stomach colon, biliary tract and pancreas, whereas 2 of 11 (18%) hepatocellular carcinomas were positive. Tn antigen was detected in the upper two-thirds of the normal squamous epithelium, and was often detected in squamous cell carcinomas with cancer pearls (keratinization). These results suggest that the expression of Tn antigen is related to the differentiation of squamous epithelium, or to keratinization. In normal columnar epithelial cells. Tn antigen was localized mainly to the Golgi area. This intracellular localization was preserved in well-differentiated papillary adenocarcinomas of the colon, but was lost in most cases of tubular adenocarcinomas.

Adenocarcinoma↗
PubMed1995

Immunoscintigraphy of colorectal cancer using 111In-labeled monoclonal antibody to mucin.

A murine monoclonal antibody MLS102 recognizes sialosyl-Tn antigen in mucin and immunohistochemically reacts with more than 80% of colorectal cancer tissues. The purpose of this study was to assess the usefulness of this monoclonal antibody for the immunoscintigraphy of colorectal cancer. Planar and SPECT images were obtained on day 2 or day 3 after injection of 2 mg and 74 MBq 111In-labeled MLS102 antibody into 17 patients with colorectal cancer. Nine of 11 primary tumors and 4 of 6 locally recurrent tumors were detected. Positive images were obtained in all tumors larger than 4.5 x 2.7 cm. Three tumors of less than 2.5 cm and 1 recurrent tumor, which was missed by other imaging modalities, were negative. There were no adverse reactions. Human anti-(mouse Ig) antibody developed in 4 patients. Although improvement of detectability for smaller tumors needs to be pursued, the antibody MLS102 is potentially promising for use in immunoscintigraphy of colorectal cancer.

Adult↗
PubMed1995

Radioimmunoimaging of colon cancer xenografts with anti-Tn monoclonal antibody.

Tn antigen is a glycosylated tumor associated antigen and a murine monoclonal antibody, MLS128, has been identified to react with it. The potential of MLS128 for the radioimmunoimaging of colorectal cancer was studied. MLS128 was labeled with radioiodine by the chloramine-T method or indium-111 (111In) by using isothiocyanatobenzyl EDTA, and was injected into nude mice bearing human colon cancer xenografts. Radiolabeled MLS128 showed a high and specific localization in xenografted tumor. At 48 h after injection, the %ID/g of 125I-labeled MLS128 in the tumor was 34.69, whereas that of isotype matched control antibody, FLOPC21, was 5.58 and the tumor-to-nontumor radioactivity ratios of 125I-labeled MLS128 reached to 4.56, 17.84 and 23.62 for the blood, liver and bone, respectively. 111In-labeled MLS128 showed similar results. High accumulation of MLS128 in xenografted tumors suggested that the monoclonal antibody MLS128 is promising for radioimmunoimaging of colorectal cancer.

Animals↗
PubMed1995

Extramedullary plasmacytoma of maxillary sinus with later involvement of the gall bladder and subcutaneous tissues.

We recently encountered a patient with extramedullary plasmacytoma (EMP) originating in the maxillary air sinus, who developed subcutaneous tissue and gall bladder involvement 2 years after initial local radiotherapy. Treatment with melphalan, prednisone and interferon led to a rapid and sustained regression of the gall bladder tumour. Complete remission was obtained by subsequent regional radiotherapy to the subcutaneous tumours in the extremities. Progression of plasmacytoma to the hepatobiliary system and subcutaneous tissues is quite rare and the effects of chemo- and radiotherapy on these lesions have not been fully elucidated. This study demonstrated that EMP can be well controlled and complete remission obtained by various therapeutic strategies, even though this tumour develops widespread dissemination.

Gallbladder Neoplasms↗
PubMed1995

Improved targeting of radiolabeled streptavidin in tumors pretargeted with biotinylated monoclonal antibodies through an avidin chase.

UNLABELLED: Radiolabeled streptavidin can be accumulated in tumors pretargeted with biotinylated anti-tumor antibodies. However, circulating biotinylated antibody and endogenous biotin may interfere with the tumor targeting of streptavidin. To reduce biotinylated antibody concentration in the blood, we injected avidin before streptavidin administration. The effects of avidin administration on the biodistribution and tumor targeting of radiolabeled streptavidin were examined. METHODS: Biotinylated anti-human colon cancer monoclonal antibody (MAb) MLS128 was injected intravenously into nude mice bearing human colon cancer xenografts for pretargeting. After intraperitoneal injection of avidin, radioiodinated streptavidin was administered and its biodistribution and tumor accumulation was investigated. RESULTS: Radioiodinated streptavidin specifically localized in the tumor pretargeted with biotinylated antibody. Avidin preadministration accelerated the tumor uptake and blood clearance of radioiodinated streptavidin. The tumor-to-blood radioactivity ratio at 6 and 24 hr after radiolabeled streptavidin injection were 1.23 +/- 0.29 and 3.04 +/- 0.86, respectively, in mice with avidin chase (mean +/- s.d., n = 7), and 0.82 +/- 0.17 and 2.29 +/- 0.29, respectively, in those without chase (mean +/- s.d., n = 7). CONCLUSION: Localization of radiolabeled streptavidin in tumors pretargeted with biotinylated MAb could be improved by avidin chase. This approach may be useful for tumor radioimmunoimaging and radioimmunotherapy.

Animals↗
PubMed1994

Tn antigen is expressed on leukosialin from T-lymphoid cells.

Various T-lymphoid cells were labeled with [3H] glucosamine and then cell lysates were prepared from them. The Tn antigen was immunoprecipitated and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by fluorography. The Tn antigen was found to be expressed on leukosialin, a major glycoprotein of T-lymphoid cells. The carbohydrate moieties of leukosialin were isolated from Jurkat and Molt 4 cells by alkaline borohydride treatment. The leukosialin in both cases predominantly contained single N-acetylgalactosamine residues, consistent with expression of the Tn antigen. Tryptic glycopeptides containing antigenic sites were isolated using an MLS 128 immunoaffinity column and purified by gel filtration and reverse phase column chromatographies. Sequence analyses revealed that all the glycopeptides obtained contained three consecutive residues of N-acetylgalactosamine-Ser/Thr, supporting the idea that the epitopic structure is a cluster of N-acetylgalactosamine-Ser/Thr.

Antigens, CD↗
PubMed1994

Coexpression of cancer-associated carbohydrate antigens, Tn and sialyl Tn.

The expression of cancer-associated antigens, Tn and sialyl Tn, was examined using monoclonal antibodies, MLS 128 and MLS 102, recognizing these two antigens, respectively. A cell lysate from a human carcinoma cell line, LS 180 cells, was analysed by Western blotting using these two antibodies. Three glycoprotein bands were discernible with each antibody, of which two, corresponding to 250 and 210 kDa, were reactive with both the antibodies. LS 180 cells were metabolically labelled with 3H-glucosamine and then the lysate from these cells was applied to two immunoaffinity columns. Sixty-five per cent of the Tn antigenic glycoproteins, based on radioactivity, bound to the MLS 102 affinity column. On the other hand, 45% of the sialyl Tn antigenic glycoproteins bound to the MLS 128 affinity column. These results indicate that some Tn and sialyl Tn antigens were expressed on the same polypeptide chains. The presence of non-sialylated GalNAc residues on the polypeptide chain with many Sia-GalNAc residues appears to be due to the incapability of three consecutive moieties of GalNAc-Ser/Thr to accept sialic acid.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1994

Expression of sialosyl-Tn antigen (monoclonal antibody MLS102 reactive) in normal tissues and malignant tumors of the digestive tract.

Oncogenic transformation is often associated with changes in the glycosylation state of malignant cells. We investigated the immunohistochemical localization of sialosyl-Tn antigen [O-linked NeuAc(alpha 2-->6)GAINAc] using a novel monoclonal antibody MLS102 in normal and malignant digestive-tract tissues. In normal tissues, weak MLS102 immunoreactivity was observed in the epithelium of the esophagus, stomach and colon. However, MLS102 immunoreactivity was strong in the goblet cells of the duodenum, but not in the Brunner glands. In carcinomas of the esophagus, stomach, colon, pancreas and biliary tract, positive staining was detected with a high frequency (80%-100%). In mucinous carcinomas and signet-ring cell carcinomas, malignant cells themselves and the mucins they secreted were strongly positive for sialosyl-Tn antigen. There was no significant correlation between the frequency of expression of sialosyl-Tn antigen and the degree of differentiation (grade). However, in the case of well-differentiated adenocarcinomas, sialosyl-Tn antigen was found mainly in the supranuclear areas (Golgi area), on the apical surface and in the adjacent cytoplasm. In poorly differentiated adenocarcinomas, the antigen was often detected in the whole plasma membrane and cytoplasm. Therefore, monoclonal antibody MLS102 may be useful in further elucidating the characteristics of digestive-tract cancers, and possibly in their treatment.

Antibodies, Monoclonal↗
PubMed1994

[Fulmonant group A streptococcal infection accompanied by massive pulmonary hemorrhage and subsequent asphyxia: a case report].

A case of fulminant group A streptococcal infection occurring in a 6-year-old Japanese child is reported. She was accompanied by massive pulmonary hemorrhage and subsequent asphyxia. She initially had pharyngalgia with fever. The cephalosporin antibiotic was given orally for 3 days. Three days after that recurrence of fever and pharyngalgia was noted. Twelve hours later tachypnea and a sudden onset of hemoptysis was noted. She manifested DOA (dead on arrival) and died in the emergency room. Autopsy revealed the presence of numerous cocci in the vessels and massive pulmonary hemorrhage. Streptococcus pyogenes was isolated from the blood. The serotype of this group A streptococcal organism was typed as M4, T4, which produces exotoxin type B and C, which was sensitive to the penicillins.

Asphyxia↗
PubMed1993

Novel gangliosides containing the sialyl-Le(a) structure from a human rectal adenocarcinoma.

Oligosaccharides were released from the gangliosides of a human rectal adenocarcinoma with endoglycoceramidase (Rhodococcus sp. G-74-2) and then purified by affinity chromatography on a column of an immobilized monoclonal antibody, MSW 113. Structural studies, involving 600-MHz 1H NMR spectrometry, indicated the structures of these compounds to be as follows. [formula: see text] Three of these oligosaccharides, 2, 3, and 4, are novel as to ganglioside sugar chains and contain both lacto series types 1 and 2 chains. Oligosaccharides 3 and 4 are unique in that they contain the sialyl-Le(a)-X structure in linear and branched structures. Gangliosides with the oligosaccharide structures presented above might be new potential tumor markers.

Adenocarcinoma↗
PubMed1993

Epitopic structure of Tn glycophorin A for an anti-Tn antibody (MLS 128).

Glycophorin A was digested with glycoprotease (Pasteurella haemolytica) and the digest was fractionated by a combination of high-pressure column chromatographies to produce the glycopeptides GPA-1 to GPA-6. Sequence analysis of the glycopeptides revealed that two serine residues (Ser-14 and Ser-15) are not glycosylated, Thr-17 and Ser-19 being glycosylated instead, in disagreement with the accepted structure. The glycopeptides thus obtained were treated with sialidase and beta-galactosidase. The Tn antigenicity, as assayed by the binding to a monoclonal anti-Tn antibody (MLS 128), was found exclusively in the glycopeptides including three (cluster I) or four (cluster II) consecutive residues of GalNAc-Ser/Thr, whereas the glycopeptide (GPA-2) containing two nonconsecutive GalNAc-Ser/Thr residues had practically no Tn antigenicity. The immunoreactivities of GPA-1 and GPA-3, containing both clusters I and II, and GPA-4, containing cluster II, were 63% (calcd. 67%), 81% (calcd. 86%), and 50% (calcd. 50%), respectively, of the immunoreactivity of GPA-5 or GPA-6, containing cluster I (the average being taken as the basis), based on the reactivity per GalNAc residue. These results indicate that clusters I and II react with the antibody to the same extent. The structure consisting of three consecutive glycosylated Ser/Thr residues may be essential for Tn antigenicity in the light of previous results for ovine submaxillary mucin.

Amino Acid Sequence↗
PubMed1993

Novel oligosaccharides with the sialyl-Le(a) structure in human milk.

Two novel oligosaccharides with the sialyl-Le(a) structure were isolated from human milk using a monoclonal antibody, MSW 113. These oligosaccharides were purified by affinity chromatography on a column of the immobilized monoclonal antibody and by high-performance liquid chromatography, and structurally characterized by a combination of 600-MHz 1H NMR spectroscopy and fast atom bombardment mass spectrometry. The structural studies indicated the structures of these oligosaccharides to be: [formula: see text]

Antibodies, Monoclonal↗