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H Nakada

Publications and source records attributed to H Nakada.

12 recordsLinked to original sources

Cancer-associated glycoproteins defined by a monoclonal antibody, MLS 128, recognizing the Tn antigen.

A murine monoclonal antibody, MLS 128, recognizing the Tn antigen, was established and used for characterization of glycoproteins expressing the Tn antigen. The Tn antigen was expressed on three polypeptide chains with molecular weights of 250k, 210k and 150k daltons. LS 180 cells were labeled with 3H-glucosamine or 35S-sulfate metabolically, and then the immunoprecipitate derived from the cell lysate was subjected to SDS-PAGE followed by fluorography. It was revealed that these Tn antigen glycoproteins were produced through the processing of a high molecular weight precursor. The carbohydrate moieties of the Tn antigen glycoproteins labeled with 3H-glucosamine were released with alkaline-borohydride, and the released sugars were examined by gel filtration and paper chromatography. The carbohydrates predominantly consisted of GalNAc and sialyl GalNAc (greater than 90%), with a nearly equal distribution.

Antibodies, Monoclonal

Novel structure of the N-acetylgalactosamine containing N-glycosidic carbohydrate chain of batroxobin, a thrombin-like snake venom enzyme.

The structure of the Asn-linked carbohydrate chain of batroxobin, a thrombin-like enzyme from Bothrops atrox moojeni snake venom, has been determined. The sugar chain was isolated from batroxobin by hydrazinolysis followed by pyridylamination (PA). The PA-oligosaccharide chain was purified by HPLC on an anion exchange or reverse phase columns, and its structure was examined by sequential exoglycosidase digestion, 600 MHZ 1H NMR spectroscopy and methylation analysis. The results indicate that the oligosaccharide chain has the following structure involving a novel linkage, NeuAc alpha 2----3GalNAc.

Acetylgalactosamine

Characterization of IL-1 inhibitory factor released from human alveolar macrophages as IL-1 receptor antagonist.

IL-1 possesses pleiotropic properties on various cells and its activity may be stringently regulated in several ways. We have previously reported that both IL-1 and its inhibitory factor are concomitantly released from alveolar macrophages in both healthy subjects and patients with chronic inflammatory lung diseases. An increase in IL-1 activities and a decrease in inhibitory activities are characteristics found in both healthy smokers and patients with interstitial lung diseases. In this study, we further examined the biological properties of IL-1 inhibitory factor. The inhibitor exhibited a dose-dependent specific inhibition of an augmentation by IL-1 of PHA-induced murine thymocyte proliferation, while no inhibition of the augmentation by IL-2, IL-4, IL-6, or tumour necrosis factor (TNF) was found. 125I-labelled IL-1 alpha binding on PHA-stimulated murine thymocytes revealed two types of IL-1 binding sites, 44 sites/cell with a Kd of 2.7 x 10(-10) M and 230 sites/cell with a Kd of 2.5 x 10(-9) M. Alveolar macrophage culture supernatants blocked the binding of labelled IL-1 to the IL-1 receptor in a dose-dependent fashion. Scatchard plot analysis revealed that the inhibitory factor in the supernatants blocked the binding competitively. These results indicate that alveolar macrophages produce a specific IL-1 inhibitory factor, functioning as an IL-1 receptor antagonist.

Cells, Cultured

[Expression of angiotensin II receptor on BALF macrophages from patients with sarcoidosis and healthy individuals].

We previously reported that angiotensin II (A-II) enhanced the accessory function of BALF macrophages in some patients with sarcoidosis. We hypothesized that this finding was mediated by the A-II receptor on BALF macrophages. From this viewpoint, we investigated the expression of A-II receptor on BALF macrophages. The binding of 125I-A-II to BALF macrophages was specifically inhibited by unlabeled A-II when incubated for 1 hour at 37 degrees C. However, the uptake of 3H-inulin to BALF macrophages was not inhibited by unlabeled inulin under the same conditions. These findings indicate that the binding of 125I-A-II to BALF macrophages was mediated by the putative A-II receptor, and was not due to pinocytosis.

Adult

[Tn antigen].

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Amino Acid Sequence

Release of glycopeptides and mucopolysaccharides from ascites hepatoma cells by tryptic treatment.

Two types of ascites hepatoma cells, AH 66 and AH 130 FN, were treated with trypsin to observe the release of complex carbohydrates constituting the plasma membranes. From AH 66 cells, mucopolysaccharide (heparan sulfate) was preferentially released. From AH 130 FN cells, N-glycosidic glycopeptides were preferentially released whereas no mucopolysaccharide (chondroitin sulfate A) was released.

Animals

The isolation and characterization of glycopeptides and mucopolysaccharides from plasma membranes of an ascites hepatoma, AH 130.

Plasma membranes were isolated from an ascites hepatoma, AH 130, by the fluorescein mercuric acetate (FMA) method. Glycopeptides and mucopolysaccharides were prepared by digesting the membranes with pronase, then by fractionating the digest chromatographically and electrophoretically. Isolated fractions were analyzed for their amino acid and carbohydrate compositions. Results were compared with those for corresponding fractions from AH 66 (J. Biochem. 76, 319-333 (1974)). Mucopolysaccharides and a series of glycopeptides were isolated from the fraction excluded from Sephadex G-50. The mucopolysaccharides were identified as a family of heparan sulfates with different electrophoretic mobilities. The glycopeptides contained serine, threonine, galactose, galactosamine, glucosamine, and sialic acid as the major constituents as aspartic acid and mannose as minor ones. This suggests that most of the carbohydrate moieties are linked to serine or threonine (O-glycosidic), and that some are linked to asparagine (N-glycosidic). No nearly purely O-glycosidic glycopeptides were found in this fraction from AH 130, through they were the major glycopeptides from the AH 66 plasma membranes. In the fraction included in the gel, glycopeptides containing fucose, galactose, mannose, glucosamine, glaactosamine, and sialic acid were found. The presence of galactosamine suggests that some of the glycopeptides are O-glycosidic though most are N-glycosidic. In the corresponding fraction from AH 66, nearly purely N-glycosidic glycopeptides were found.

Animals

[Evaluation of ototoxicity of amikacin (BB-K8) by animal test (author's transl)].

Seventy Hartley strain guinea pigs (350 g body weight at start of the experiment) were used. BB-K8, gentamicin (GM) and kanamycin (KM) were given to the animals intramuscularly for 28 days at following various doses: (see article) These guinea pigs underwent a differential frequency pinna reflex test in wide frequency range from 20KHz to 0.5 KHz before the administration, during the injection and after the last one. For histopathological examination of the inner ears the guinea pigs were subjected to intravital fixation with Wittmaack's fixative under nembutal general anesthesia. Blocks including the bilateral temporal bones were removed from the skulls and then fixed in the same fixative for 1 similar to 2 weeks. After routine procedure for decalcification, dehydration and celloidin embedding, horizontal serial sections of the inner ears were made and stained with hematoxylin-eosin. The differential frequency pinna relfex test in the 70 guinea pigs indicated positive pinna reflex in 90% at 20KHz and in 100% at 15, 12, 10, 8, 6, 4, 3, 2, 1 and 0.5 KHz before start of the administration. Administration of the antibiotics for 28 days occasionally resulted in the pinna reflex loss which always involved the highest frequency, 20 KHz and then was followed in relatively regular succession by 15, 12, 10, 8, 6, 4, 3, 2, 1 and 0.5 KHz (Tables 1 similar to 8). On the other hand, histopathological examination of the inner ears disclosed that the loss of the outer hair cells in the spiral organ which are the most sensitive to the ototoxic antibiotics, occurred always at the basal end of the spiral organ and then spread from there to upper portion of the spiral organ (Tables 9 similar to 16). Based on the differential frequency pinna reflex test in the wide frequency range and extensive histopathological examination of the inner ears, ototoxicity of BB-K8 is considered to be more mild than GM. However, there was not so remarkable difference in ototoxicity between BB-K8 and KM in the present experiment. The result or examination of the guinea pigs received BB-K8 at 40 mg/kg and 100 mg/kg respectively for 28 days suggests that BB-K8 at expecting clinical dose, 500 mg per day (for 28 days) may be safe from ototoxicosis in the inner ears. In the vestibular organs of the animals received BB-K8 there was no decrease in number of the hair cells.

Amikacin