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991.
Akio Abe Ichiro Ito Midori Ohkubo Takehisa Kaneko Kohichi Ito Hidehito Kato Noboru Kashiwagi Fumiya Obata 《Immunogenetics》1989,30(6):422-426
We determined the DNA sequence of the enzymatically amplified second exon of theDRB1 gene of theDRw12 haplotypes derived from three Japanese donors and found two distinct subtypes of theDRw12 haplotype. The two subtypes, designatedDRw12a andDrw12b, had single-base substitutions that predicted one amino acid change at residue number 67. The sequence of theDrw12a andDRw12b subtypes differed from those of the otherDR haplotypes, but in the first hypervariable region of theDRB1 gene the sequences were identical to those of theDRw8(Dw8.1) andDRw8(Dw8.3) haplotypes. TheDRw12a andDRw12b subtypes were detected in a wide range of Japanse donors by genotyping with sequence-specific oligonucleotide probes synthesized
according to the DNA sequence of the two subtypes. Results of this study demonstrated that theDRw12 haplotypes in the Japanese population are genetically diverse, as many otherDR haplotypes are.
The nucleotide sequence data reported in this paper have been submitted to the GenBank nucleotide sequence database and have
been assigned the accession numbers M27509, M27510, M27511. 相似文献
992.
Lipase from Pseudomonas fragi 22.39B was modified with polyethylene glycol. The modified lipase (PEG-lipase) was soluble and active in organic solvents such as benzene and 1,1,1-trichloroethane. PEG-lipase catalyzed esterification of chiral secondary alcohols with fatty acids in benzene and exhibited preference for R isomers over S isomers. Km and Vmax values for each isomer of various alcohols were obtained by kinetic study of the esterification in benzene. PEG-lipase-catalyzed esterification leads to optical resolution of a racemic alcohol. 相似文献
993.
Summary The effects of melatonin on synaptic ribbons (SR) in pinealocytes of the Chinese hamster (Cricetulus griseus) were examined. SR were classified into types 1, 2 and 3, which appear as rods, round or irregular bodies and ring-shaped structures, respectively; a synaptic ribbon index (SR index) was determined for the three types. Administration of two doses of 1.5 mg/kg melatonin at noon and 3 p.m. causes an increase in the type-1 and type-2 SR indices 3 h after the second injection in hamsters kept under alternating light and dark conditions (lights on from 7 a.m. to 7 p.m.). Likewise, in animals that are exposed to extended light for 6 h and receive two doses of melatonin at 7 p.m. and 10 p.m., an increase in the type-1 and type-2 SR indices occurs 3 h after the second injection. The increase in the type-2 SR index induced by melatonin administration to hamsters exposed to extended light is greater than the increase in the type-1 SR index under the same experimental conditions. Type-2 SR index, but not type-1 SR index, increases following bilateral superior cervical ganglionectomy. An increase in type-1 and type-2 SR indices occurs at 6 p.m. in ganglionectomized animals administered two doses of melatonin 6 h (noon) and 3 h (3 p.m.) before the time of sacrifice. No significant change is observed in type-3 SR index in animals subjected to any of the above treatments. The results indicate that exogenous melatonin may act directly on pinealocytes of the Chinese hamster to cause an increase in size and/or number of the type-1 and type-2 SR. Type 3-SR may have a role different from that of type-1 and type-2 SR; type-1 and type-2 SR may be functionally related. 相似文献
994.
Smith Fred B. Kikkawa Yutaka Diglio Clement A. Dalen Ruth C. 《In vitro cellular & developmental biology. Plant》1982,18(4):331-338
Summary We found that fetal bovine serum supplementation of culture medium provided limited quantities of linoleic acid, an essential
fatty acid, to cells grown in culture (2.8 ± 0.3% of total fatty acids in 12 lots). Supplementation of the medium with additional
linoleic acid resulted in altered phospholipid acyl composition in cells of two established lines, A549, a putative model
of the pulmonary Type II epithelial cell, and SIRC, a line derived from rabbit corneal epithelium. In particular, linoleic
acid supplementation induced a relative increase in disaturated choline phosphoglycerides of 33 and 36%, respectively, in
cells of the two lines. This observation may be relevant to design of media for primary culture of Type II cells, in which
disaturated phospholipid synthesis is used as an index of differentiated function (surfactant production). Linoleate supplementation
did not alter growth or size (protein content) of cells of either line and caused a slight increase in accumulation of neutral
lipid, in the form of cytoplasmic droplets, in A549 cells. Supplementation of cell cultures with equivalent concentrations
of the nonessential fatty acids palmitic and oleic acid did not significantly alter the growth, morphologic appearance, or
lipid composition of the cells. However, it was demonstrated in cells of one line that palmitic acid supplementation temporarily
stimulated synthesis of disaturated choline phosphoglyceride from radiolabeled choline.
This work was supported by Grants HL-24817 and HL-21251 from the National Institutes of Health, USPHS, and by a grant from
the Alexandrine and Alexander L. Sinsheimer Fund. 相似文献
995.
Akira Hasegawa Yoshimi Kaneda Yasuhiko Goh Kaoru Nishibori Makoto Kiso Ichiro Azuma 《Carbohydrate research》1981,94(2):143-163
2-Acetamido-2-deoxy-4- and -6-O-(d-2-propanoyl-l-alanyl-d-isoglutamine)-d-glucopyranose, 2-acetamido-2-deoxy-3-O-(d-2-propanoyl-l-alanyl-d-isoglutamine)-d-allopyranose, -d-gulopyranose, -d-galactopyranose, -d-mannopyranose, and -l-idopyranose, and 3-O-(d-2-propanoyl-l-alanyl-d-isoglutamine)-d- and -l-glucopyranose were synthesized, in order to clarify the structural requirements for the immunoadjuvant activity of the carbohydrate moiety in N-acetylmuramoyl-l-alanyl-d-isoglutamine. Immunoadjuvant activity of the N-acetylmuramoyl-dipeptide analogs was examined in guinea-pigs. 相似文献
996.
Uninucleate microspores of Lilium longiflorum isolated at theGi phase of the cell cycle were cultured on a solid nutrientmedium for 12 days. The typical pollens produced in the culturegerminated on a germination medium and developed a structureresembling a pollen tube. The elongating pollen tubes occasionallycontained dividing generative nuclei or two sperm nuclei. (Received September 29, 1980; Accepted November 25, 1980) 相似文献
997.
Ichiro Okura Ken-ichi Nakamura Satoshi Nakamura 《Journal of inorganic biochemistry》1981,14(2):155-161
The reduction of methyl viologen by hydrogen with hydrogenase was studied kinetically. The initial rate of the reduction was expressed as where k′, K2, and K3 are constants and [S′] is the concentration of methyl viologen.According to this equation, a sequential mechanism was proposed. By combining the mechanism of hydrogen production from the reduced methyl viologen, a reaction mechanism for the reduction and oxidation of methyl viologen was proposed. 相似文献
998.
Kousaku Murata Keiko Tani Jyoji Kato Ichiro Chibata 《Enzyme and microbial technology》1981,3(3):233-242
Efficient ATP generation is required to produce glutathione and NADP. Hence, the generation of ATP was investigated using the glycolytic pathway of yeast. Saccharomyces cerevisiae cells immobilized using polyacrylamide gel generated ATP from adenosine, consuming glucose and converting it to ethanol and carbon dioxide. Under optimal conditions, the ATP-generating activity of immobilized yeast cells was 7.0 μmol h?1 ml?1 gel. A column packed with these immobilized yeast cells was used for continuous ATP generation. The half-life of the column was 19 days at a space velocity of (SV) 0.3 h?1 at 30°C. The properties of glutathione- and NADP-producing reactions coupled with the ATP-generating reaction were investigated. Escherichia coli cells with glutathione synthesizing activity and Brevibacterium ammoniagenes cells with NAD kinase activity were immobilized in a polyacrylamide gel lattice. Under optimal conditions, the immobilized E. coli cells and immobilized B. ammoniagenes cells produced glutathione and NADP at the rates of 2.1 and 0.65 μmol h?1 ml?1 gel, respectively, adding ATP to the reaction mixture. In order to produce glutathione and NADP economically and efficiently, the glutathione- and NADP-producing reactions were finally coupled with the ATP-generating reaction catalysed by immobilized S. cerevisiae cells. To compare the productivities of glutathione and NADP, and to compare the efficiency of ATP utilization for the production of these two compounds, the two reactor systems, co-immobilized cell system and mixed immobilized cell system, were designed. As a result, these two compounds were also found to be produced by these two kinds of reactor systems. Using the data obtained, the feasibility and properties of ATP generation by immobilized yeast cells are discussed in terms of the production of glutathione and NADP. 相似文献
999.
1000.
Fumiya Obata Ichiro Ito Koichi Ito Akio Abe Midori Ohkubo Keiji Onda Yong-guang Yang Koji Watanabe Noboru Kashiwagi 《Immunogenetics》1990,32(5):313-320
Analysis of a Japanese population by oligonucleotide genotyping revealed that one Japanese HLA-DRw14 allele had a DRB1 genotype different from that of the known HLA-DRw14-related alleles, DRB1
*
1401 (DRw14-Dw9) and DRB1
*
1402 (DRw14-Dw16). The second exon of the DRB1 gene of the novel DRw14 allele (designated DRB1-14c) was amplified enzymatically and sequenced after cloning intto a plasmid vector. The amino acid sequence of the first domain in the DR1 chain encoded in the DRB1-14c allele was more similar to that of the DRB1
*
1401 allele (three amino acid substitutions).than to that of the DRB1
*
1402 allele (six amino acid substitutions). No polymorphic amino acid residue that could explain the common serologic HLA-DRw14 specificity was identified among the sequences of the three DRw14-related alleles. Sequence-specific oligonucleotides (SSOs) were synthesized on the basis of the DRB1-14c nucleotide sequence and used for genotyping of the Japanese population. These SSOs served as useful probes for identifying the DRB1-14c allele in a wide range of donors.The nucleotide sequence data reported in this paper have been submitted to the GenBank nucleotide sequence database and have been assigned the accession number M33693. 相似文献