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Biomedical subjects

H Iijima

Publications and source records attributed to H Iijima.

At least 163 records · Page 9Linked to original sources

Synthesis of a mucin-type O-glycosylated amino acid, beta-Gal-(1----3)-[alpha-Neu5Ac-(2----6)]-alpha-GalNAc-(1----3)- Ser.

Total synthesis of O-beta-D-galactopyranosyl-(1----3)-O-[(5-acetamido-3,5-dideoxy- D-glycero-alpha-D-galacto-2-nonulopyranosylonic acid)-(2----6)]-O-(2-acetamido-2-deoxy-alpha-D-galactopyranosyl)-(1----3 )-L- serine was achieved by use of the key glycosyl donor O-(2,3,4,6-tetra-O-acetyl-beta-D-galactopyranosyl)-(1----3)-O- [methyl (5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-D-glycero-alpha-D-galact o-2- nonulopyranosyl)onate-(2----6)]-4-O-acetyl-2-azido-2-deoxy-a lpha-D- galactopyranosyl trichloroacetimidate and the key glycosyl acceptor N-(benzyloxycarbonyl)-L- serine benzyl ester in a regiocontrolled way.

Carbohydrate Conformation↗

Synthesis of a fully protected derivative of O-(N-acetyl-alpha-D-neuraminyl)-(2----3)-O-beta-D-galactopyranosyl-(1- ---3)-O- [(N-acetyl-alpha-D-neuraminyl)-(2----6)]-O-(2-acetamido-2-deoxy-alpha- D-galactopyranosyl)-(1----3)-L-serine.

N-(Benzyloxycarbonyl)-O-[methyl (5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-D-glycero-alpha-D-galact o-2- nonulopyranosyl)onate]-(2----3)-O-(2,4,6-tri-O-acetyl-beta-D - galactopyranosyl)-(1----3)-O-[methyl (5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-D-glycero-alpha-D-galact o-2- nonulopyranosyl)onate-(2----6)]-O-(2-acetamido-4-O-acetyl-2- deoxy-alpha-D- galactopyranosyl)-(1----3)-L-serine benzyl ester was synthesized by using O-[methyl (5-acetamido-4,7,8,9-tetra-O-acetyl-3,5- di-deoxy-D-glycero-alpha-D-galacto-2-nonulopyranosyl)onate]- (2----3)-O-(2,4,6- tri-O-acetyl-beta-D-galactopyranosyl)-(1----3)-O-[methyl (5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-D-glycero-alpha-D-galact o-2- nonulopyranosyl)onate-(2----6)]-4-O-acetyl-2-azido-2-deoxy-a lpha- and -beta-D-galactopyranosyl trichloroacetimidate as a key glycotetraosyl donor which, upon reaction with N-(benzyloxycarbonyl)-L-serine benzyl ester, afforded a 44% yield of a mixture of the alpha- and beta-glycosides in the ratio of 2:5.

Carbohydrate Conformation↗

Direct write-out of particle size distribution of inhaled aerosol deposition using a laser scattering method.

We developed a device to measure inhaled aerosol deposition in the lung from the difference in particle size distribution of the aerosol during inspiration and expiration. To measure quantity and size distribution of nebulized aerosol particles directly at the subject's mouth we used a He-Ne gas laser scattering technique. To test the reliability of the instrument, we measured particle size distributions of saline aerosols generated by four kinds of nebulizer and compared the results with those from a Malvern 2600D particle sizer as a standard of comparison. Measured mass median diameters (MMDs) were almost identical by both methods. Aerosol deposition in five normal subjects showed that the deposition fraction of the particles increased the larger the particle sizes inhaled. The data suggest that the newly developed aerosol spectrometer can directly analyze aerosol particle size distribution at the mouth during tidal breathing, and that the instrument is useful for quantitative analysis of aerosol inhaled and of inhaled aerosol deposition.

Aerosols↗

A novel method for removal of human immunodeficiency virus: filtration with porous polymeric membranes.

We propose a new method to rid solutions of a virus by using a novel regenerated multilayered structured cellulose membrane (BMM). When the filtrate of human immunodeficiency virus (HIV) preparation was obtained through BMM it showed no infectivity. Electron microscopic observation revealed that HIV was completely caught by the multilayers of the BMM. Conveniently, BMM was seldomly found to adsorb protein molecules and also to have a high filtration rate. These characteristics may have a use in the removal of other variously sized pathogenic agents from plasma.

Cells, Cultured↗

The pattern electroretinogram in glaucoma: an evaluation by relative amplitude from the Bjerrum area.

A new concept for evaluating the pattern electroretinogram (PERG) in glaucoma and its clinical application are described. The PERG was elicited by two different stimulus fields, namely, the whole central retinal area with a radius of 18 degrees and the paracentral ring area between the radius of 10 degrees and 18 degrees. The amplitude of the PERG for each stimulus field and the ratio of them were analysed for 30 patients with glaucoma or ocular hypertension. Among these only a small number of eyes were detected as abnormal when we evaluated the amplitude itself either with the central stimulus or the paracentral ring stimulus, whereas the ratio of the two values was below normal in some cases of advanced glaucoma. We conclude that the ratio of the paracentral to central PERG is useful for detecting glaucoma.

Adolescent↗

Autosomal dominant retinitis pigmentosa: a log quotient analysis of the photopic and scotopic b-wave amplitude.

The relationship of the photopic and the scotopic b-wave amplitudes of the electroretinogram was studied in 85 normal subjects and 25 patients with autosomal dominant retinitis pigmentosa, in which one amplitude was at least 20 microvolts. The log quotient of their b-wave amplitudes--that is log of the photopic b-wave amplitude divided by the scotopic b-wave amplitude--was considered to represent the activity of cones relative to rods. The log quotient values had a normal gaussian distribution in the normal control eyes, while they formed two groups in the patients with autosomal dominant retinitis pigmentosa. In the first group (type 1), the scotopic b-wave was non-recordable while the photopic b-wave amplitude was larger than 20 microvolts in all cases, indicating that the log quotient is larger than 0.5 and that the rod system is much more severely affected than the cone system. The second group (type 2) had a log quotient smaller than 0.5 and its distribution almost overlapped the normal one, indicating more symmetrical damage in the cone and rod systems. The mean final rod threshold at 45 minutes for type 1 was significantly higher than that for type 2. The log quotient proved to be a useful index for analysing the cone and rod involvement and consequently provides a better understanding of autosomal dominant retinitis pigmentosa.

Adolescent↗

Treatment with Krestin combined with mitomycin C, and effect on immune response.

The combination effects of Krestin (PSK) and mitomycin C (MMC) were examined in experimental tumor models. PSK was administered either orally or intraperitoneally. Delayed-type footpad reaction and antibody formation against sheep erythrocytes were measured in hosts of which immune functions were depressed by tumor burden. Results of the experiment indicated that the simultaneous administration of PSK and MMC significantly increased the survival rate of tumor-bearing mice and restored more effectively their immune functions compared to those of nontreated tumor-bearing controls or tumor-bearing hosts treated with a single agent.

Animals↗

Neurokinin A-induced bronchial hyperresponsiveness to methacholine in Japanese monkeys.

The present study was designed to investigate whether neurokinin A (NKA) and substance P (SP) increase bronchial responsiveness to methacholine (MCh). Before and 1, 2, 3 and 4 weeks after three Japanese monkeys had inhaled 10(-8) M NKA and 10(-8) M SP for 2 min, bronchial responsiveness to inhaled MCh was evaluated. Pulmonary flow resistance (R1) and dynamic lung compliance (Cdyn) were used as pulmonary function tests. Dose-response curves of R1 to inhaled MCh were shifted to the left 1 to 4 weeks after NKA treatment, compared with that obtained before treatment. However, SP treatment did not change the R1 dose-response curve. Thus, bronchial responsiveness to MCh was increased by inhalation of 10(-8) M NKA in Japanese monkeys.

Airway Resistance↗

[The influence of the operating positions on the prepared abutment contour of full cast crowns. Unanatomical artificial teeth for fixed bridge].

With a view to research the effect of the crown form, we made the unanatomical artificial teeth and some doctors to do the abutment tooth preparation with full cast crowns for the maxillar left fixed prosthodontics three-unit bridge in random position. After that, following are the results of a study made on the influence to the prepared tooth form. The prepared teeth are the second premolar and the second molar (The "second premolar" is abbreviated to "5" and the "second molar" is abbreviated to "7"). 1. The reductions of occlusal surface was excessively larger at 5 and 7 buccal cusp regions, while it was excessively smaller at central groove area. 2. The reductions of axial surface and subgingival area were excessively smaller at 5 and 7. 3. As for the degree of axial taper, its was steeper toward the buccal and distal surfaces at 5 and 7. 4. As for the relative degree of axial taper, it get the largest in degree on both sides between 5 medial surface and 7 distal surface. The results of this experiment are similar to the results that used anatomical artificial teeth. These results are affected by the operating posture.

Crowns↗

[Clinical use of castable ceramics (OCC) crown].

The new ceramics material (OCC) was developed for the purpose of aesthetic restration which can be fabricated by an usual lost wax process and it produces accurate marginal fit. OCC possesses mechanical, chemical, and physical properties. This article is discussed utility and security of OCC complete crown on the clinical application from Dec, 1986 to Jun, 1989. The results may be summarized as follows: 1) 2 of 69 cases were broken down in the period from Dec, 1986 to Jun, 1989. These reasons are caused by the lack of occlusal thickness and unsuitable fit of crown. 2) Although 4 of 69 cases are stained by tobacco tar and 5 of 69 cases are suffered from plaque accumulation, these staining and plaque accumulation are improved by plaque control. 3) An allergic reaction or an abnormality of oral tissues haven't been recognized during test period of clinical use. Consequently OCC crown showed itself about safety and usefulness.

Crowns↗

[Two cases of temporomandibular arthrosis of young children].

Two cases of temporomandibular arthrosis were reported. Case 1 was a 6 years 4 months old female with pain in her left mandibular region in moving her jaw. Opening of the mouth by herself was slightly limited. Clicking noise was seen and felt from both of her temporomandibular joints. She was in the dental developmental stage IIA by Hellman, and had deep overbite (5mm). Roentogenographic examination revealed a bony defect on her left condylar head. Treatment was performed with an activator. Pain was not felt and the mandibular opening recovered after 2 weeks of treatment. Roetogenographs showed no bony defect on her left condylar head after 5 months of treatment. Case 2 was a 3 years 2 months old male with clicking noise from both of his temporomandibular joints. There was no pain and no limitation of his mouth opening. He was in the dental developmental stage IIA by Hellman, and had large overjet (8mm). He has thumb sucking habit since the age of one year. He is now under regular observation.

Activator Appliances↗

A monoclonal antibody that recognizes a cluster of a disaccharide, NeuAc alpha(2----6)GalNAc, in mucin-type glycoproteins.

The structure of an epitopic carbohydrate recognized by a monoclonal antibody, MLS 102, was determined. A disaccharide, NeuAc alpha (2----6)GalNAc, the major prosthetic group of ovine submaxillary mucin (OSM) and related synthetic glycosides, NeuAc alpha(2----6)GalNAc alpha----Ser, NeuAc alpha(2----6)GalNAc beta----Ser, and NeuAc alpha (2----6)GalNAc beta----propyl, reacted with MLS 102 to similar extents, but the reaction was considerably weaker compared to that of OSM. This difference in reactivity could be ascribed to the occurrence of a cluster of the disaccharide on OSM. Purification of MLS 102-reactive antigens from a Triton X-100 extract of LS 180 cells by means of immunoaffinity chromatography gave mucin fractions (cMLS 102 antigen) with an OSM-like domain. Correlation between the content of the disaccharide, NeuAc alpha(2----6)GalNAc, in mucins and their reactivity with MLS 102 was observed.

Antigen-Antibody Complex↗

Preparation and characterization of monoclonal antibodies directed to the tumor-associated O-linked sialosyl-2----6 alpha-N-acetylgalactosaminyl (sialosyl-Tn) epitope.

Two monoclonal antibodies, TKH1 and TKH2, directed toward the sialosyl-Tn structure (NeuAc alpha 2----6GalNAc alpha 1----O-Ser or Thr), which display a remarkable immunohistological tumor specificity, were generated by immunization with ovine submaxillary mucin. The reactivity of these antibodies was monitored by solid phase enzyme-linked immunosorbent assay with different native and glycosidase-treated mucins and glycoproteins. Binding of the antibody to ovine submaxillary mucin glycoprotein was strongly inhibited by the O-linked disaccharide NeuAc alpha 2----6GalNAc alpha 1----O-serine, less strongly by NeuAc alpha 2----6GalNAc beta 1----O-propyl, and weakly by the monosaccharide GalNac. The reactivity was compared with previously established anti-Tn antibodies B72.3, NCC-Lu-35, and NCC-Lu-81. The antibody B72.3 was prepared previously after immunization with metastatic breast adenocarcinoma and its epitope was claimed to be GalNAc alpha 1----O-Ser (or - Thr) by Springer and associates [Springer, G.F., et al. In: T. Dao, et al. (eds.), Tumor Markers and Their Significance in the Management of Breast Cancer, pp. 47-70. New York: A.R. Liss, 1986]. The antibody was found to show very similar reactivity as that of TKH1/TKH2, and its reactivity to ovine submaxillary mucin was inhibited specifically by NeuAc alpha 2----6GalNAc alpha 1----O-serine, indicating that the antibody is clearly directed to sialosyl-Tn antigen. Immunohistological study of the distribution of this antigen in various normal human tissues and carcinomas by TKH1/TKH2 antibodies, as well as B72.3 and monoclonal antibodies NCC-Lu-35/81, which are directed to GalNAc alpha 1----O-Ser or Thr (Tn), was performed. The sialosyl-Tn antigen was not found in normal tissue except for a weak expression in Leydig cells of the testis, goblet cells of the colon, and parietal cells of the stomach. In contrast, the sialosyl-Tn antigen was strongly expressed in a large number of adenocarcinomas. As expected from the specificity studies, B72.3 shows the same reactivity as TKH1 and TKH2. Thus, both sialosyl-Tn (NeuAc alpha 2----6GalNAc alpha 1----O-Ser/Thr) and Tn (GalNAc alpha 1----O-Ser/Thr) are good tumor markers, and combined use of antibodies directed to these structures might be useful in the screening and classification of cancer.

Animals↗

Total synthesis of 3-O-[2-acetamido-6-O-(N-acetyl-alpha-D-neuraminyl-2-deoxy- alpha-D-galactosyl]-L-serine and a stereoisomer.

O-(5-Acetamido-3,5-dideoxy-D-glycero-alpha-D-galacto-2- nonulopyranoxylonic acid)-(2----6)-O-(2-acetamido-2-deoxy-alpha-D-galactopyranosyl)-(1----3) -L-serine, a structural unit occurring in various submaxillary mucins, was synthesized for the first time by using O-[methyl (5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-D-glycero-alpha-D- galacto-2-nonulopyranosyl)onate]-(2----6)-3,4-di-O-acetyl-2- azido-2-deoxy-D- galactopyranosyl trichloroacetimidate (13) and N-(benzyloxycarbonyl)-L-serine benzyl ester as the key intermediates. The trichloroacetimidate 13 was prepared by starting from two monosaccharide synthons, namely, allyl 2-azido-2-deoxy-beta-D-galactopyranoside and methyl (5-acetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-D-glycero-beta-D- galacto-2-nonulopyranosyl chloride)onate, which were coupled in the presence of silver triflate in tetrahydrofuran to give the desired alpha-(2----6)-linked disaccharide in moderate selectivity.

Disaccharides↗

Molecular cloning of complementary DNA encoding one of the human pancreatic protease E isozymes.

We have cloned a DNA from a human pancreatic cDNA library using a cloned rat pancreatic elastase 1 cDNA as a probe, and determined its nucleotide sequence. This cDNA contains a coding region of 810 nucleotides which encodes a 270-amino-acid protein. The deduced amino acid sequence shows less than 60% homologies with rat and porcine pancreatic elastase 1, although its substrate binding region is homologous with those of the above elastases 1. When this deduced amino acid sequence was compared with known amino acid sequences of pancreatic proteases other than elastases, it was found to contain an amino acid sequence which was highly homologous with the N-terminal amino acid sequence of porcine pancreatic protease E. We also purified human pancreatic protease E isozymes from human pancreatic juice, and determined their N-terminal amino acid sequences. One of the isozymes does not hydrolyze elastin but does hydrolyze a synthetic substrate. Endoglycosidase F digests glycoside bonds of the isozyme. These results suggest that the cDNA cloned by us corresponded to one of the human protease E isozymes.

Amino Acid Sequence↗

Antitumor and other effects of 24R,25-dihydroxycholecalciferol in Lewis lung carcinoma causing abnormal calcium metabolism in tumor-bearing mice.

Lewis lung carcinoma was found to cause hypercalcemia in tumor-bearing mice. 24R,25(OH)2D3 (K-DR, prepared by Kureha Chemical Ind.) significantly prolonged the survival time of mice with Lewis lung carcinoma. K-DR exhibited an antimetastatic effect on Lewis lung carcinoma, and also had an analgesic effect in mice with Lewis lung carcinoma.

Analgesics↗