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11.
Hisashi Miyazaki Masatoshi Iida Yoshimasa Matsunaga Toshihiko Fujii Keiko Nambu Hideki Amejima Yoshinori Oh-e Hideo Furukawa Yukiharu Matsui Yasunobu Sohmura Masahisa Hashimoto 《Biotherapy》1989,1(1-2):47-57
The mode of antitumor action of rHu-TNF was elucidated in BALB/c mice bearing Meth A fibrosarcoma 7 days after transplantation with respect to time course, dose-response relationships and selectivity of the effects. The maximal cytotoxic effect on tumor cells revealed by inhibition of DNA synthesis and maximal lesional effect on tumor vasculature revealed by change in blood pool-size in the tissue were detected at 30 min and I h after administration of rHu-TNF, respectively. The dose-response relationship between cytotoxic and tumoricidal effects of rHu-TNF was irrespective of administration route. ED50s of these antitumor effects afteri.v. administration of rHu-TNF were about 50 times as high as ED50s afteri.t. administration. ED50 ofi.t. given rHu-TNF for vascular effect was about 20 times as high as that for cytotoxicity while ED50 ofi.v. rHu-TNF for vascular effect was only 2–3 times as high as that for cytotoxicity. The whole body autoradiographies with [125I] HSA giveni.v. to see the blood influx into tumor tissue and [14C]thymidine given i.v. to see DNA synthesis in the whole body after administration of rHu-TNF revealed that the distribution of radioactivity was markedly changed in the tumor alone without any detectable change in other whole body tissues.In conclusion, thein vivo antitumor effect of rHu-TNF giveni.t. ori.v., appears to be exerted through the direct action on Meth A sarcoma rather than indirectly on tumor vasculature. Under present conditions, the effect of rHu-TNF in the whole body tissues seems rather selective on cells and vasculature of the tumor. 相似文献
12.
Identification of a common molecular basis for combined 17α-hydroxylase/17,20-lyase deficiency in two Mennonite families 总被引:1,自引:0,他引:1
Keiko Kagimoto Michael R. Waterman Masaaki Kagimoto P. Ferreira Evan R. Simpson Jeremy S. D. Winter 《Human genetics》1989,82(3):285-286
Summary During the course of studies to characterize mutations of the CYP17 gene that cause the 17-hydroxylase-deficient form of congenital adrenal hyperplasia we have discovered two ostensibly unrelated Mennonite families in which affected individuals are homozygous for the same mutation. The defect is a four-base duplication in exon 8 of the CYP17 gene, which alters the reading frame encoding the C-terminal 26 animo acids of cytochrome P45017. 相似文献
13.
Zhi-Hui Su Osamu Tominaga Takeshi Ohama Eiji Kajiwara Ryoshuke Ishikawa Tokindo S. Okada Keiko Nakamura Syozo Osawa 《Journal of molecular evolution》1996,43(6):662-671
Molecular phylogenetic analyses using mitochondrial NADH dehydrogenase subunit 5 (ND5) gene sequences representing all 15 species and the majority of subspecies or races of theOhomopterus ground beetles from all over the Japanese archipelago have uncovered a remarkable evolutionary history. Clustering of the species in the molecular phylogenetic tree is linked to their geographic distribution and does not correlate with morphological characters. Taxonomically the same species or the members belonging to the same species-group fall out in more than two different places on the ND5 tree. Evidence has been presented against a possible participation of ancestral polymorphism and random lineage sorting or of hybrid individuals for the observed distribution of mitochondrial DNA haplotypes. The most plausible explanation of our results is that parallel evolution took place in different lineages. Most notably,O. dehaanii, O. yaconinus, andO. japonicus in a lineage reveal almost identical morphology with those of the same species (or subspecies) but belonging to the phylogenetically remote lineages.The nucleotide sequence data reported in this paper will appear in the DDBJ, EMBL, and GenBank nucleotide sequence databases with accession numbers D50711-DD-50733 and D87131-D87186. 相似文献
14.
Novel mono-O-acetylated GM3s, one containing 9-O-acetylN-glycolyl neuraminic acid and another containing 6-O-acetyl galactose, were isolated as a mixture from equine erythrocytes, and the structures were characterized by one- and two-dimensional proton nuclear magnetic resonance (NMR) and fast atom bombardment-mass spectrometry (FAB-MS). The position of theO-acetyl residue was identified by the downfield shift of the methylene protons at C-9 ofN-glycolyl neuraminic acid (9-O-Ac GM3) and C-6 of galactose (6-O-Ac GM3) in the NMR spectrum, in comparison to the respective non-acetylated counterparts. To confirm the presence of 6-O-Ac GM3, theO-acetylated GM3 mixture was desialylated withArthrobacter neuraminidase, giving 6-O-acetyl galactosyl glucosylceramide, the structure of which was estimated by NMR and FAB-MS, together with non-acetylated lactosylceramide with a ratio of 1:1.
Abbreviations: Ac, acetyl; Gc, glycolyl; NeuGc,N-Gc neuraminic acid; GM3 (Gc), GM3 containing NeuGc (II3NeuGc-LacCer); 4-O-Ac GM3 (Gc), GM3 containing 4-O-Ac NeuGc; 9-O-Ac GM3 (Gc), GM3 containing 9-O-Ac NeuGc; 6-O-Ac GM3 (Gc), GM3 containing 6-O-Ac Gal; 1D-NMR, one-dimensional nuclear magnetic resonance spectrometry; 2D-COSY, two-dimensional chemical shift-correlated spectrometry; FAB-MS, fast atom bombardment-mass spectrometry; GLC, gas-layer chromatography; GC-MS, gas chromatography-mass spectrometry; TLC, thin-layer chromatography; Ggl, ganglioside; Cer, ceramide; CMH, monohexosylceramide; LacCer, lactosylceramide; 6-O-Ac LacCer, LacCer containing 6-O-Ac Gal; Me2SO-d6,2H6-dimethylsufloxide; CMW, chloroform-methanol-water; Nomenclature and abbreviations of glycosphingolipids follow the system of Svennerholm (J Neurochem [1963]10: 613–23) and those recommended by the IUPAC-IUB Nomenclature Commission (Lipids [1977]12: 455–68). 相似文献
15.
Keiko Tadano-Aritomi Harumi Kubo Philip Ireland Takeshi Kasama Shizuo Handa Ineo Ishizuka 《Glycoconjugate journal》1996,13(2):285-293
A novel mono-sulfated glycosphingolipid based on the gangliotriaose core structure was isolated from rat kidney. The isolation procedure involved extraction of lipids with chloroform/methanol, mild alkaline methanolysis, column chromatographies with anion exchangers and silica beads. The structure was characterized by compositional analysis, FTIR spectroscopy, methylation analysis,1H-NMR spectroscopy and negative-ion liquid secondary ion mass spectrometry (LSIMS) using the intact glycolipid and its desulfation product. The two dimensional chemical shift correlated spectroscopy provided information on the sugar sequence as well as anomeric configurations, and indicated the presence of a 3-O-sulfatedN-acetylgalactosamine within the molecule. Negative-ion LSIMS with high- and low-energy collision-induced dissociation defined the sugar sequence and ceramide composition, confirming the presence of a sulfatedN-acetylgalactosamine at the non-reducing terminus. From these results, the complete structure was proposed to be HSO3-3GalNAc1-4Gal1-4Glc1-1Cer (Gg3Cer III3-sulfate, SM2b).
Abbreviations: Abbreviations for sulfated glycolipids [17] follow the modifications of the nomenclature system of Svennerholm for gangliosides [37], and the designation of the other glycosphingolipids follows the IUPAC-IUB recommendations [38]. Cer, ceramide; LacCer, lactosylceramide, Gal1-4Glc1-1Cer; Gg3Cer, gangliotriaosylceramide, GalNAc1-4Gal1-4Glc1-1Cer; Gg4Cer, gangliotetraosylceramide, Gal1-3GalNAc1-4Gal1-4Glc1-1Cer; iGb4Cer, isoglobotetraosylceramide, GalNAc1-3Gal1-3Gal1-4Glc1-1Cer; Gb4Cer, globotetraosylceramide, GalNAc1-3Gal1-4Gal1-4Glc1-1Cer; SM4s, galactosylceramide sulfate, GalCer I3-sulfate; SM3, lactosylceramide sulfate, LacCer II3-sulfate; SM2a, Gg3Cer II3-sulfate; SM2b, Gg3Cer III3-sulfate; SB2, Gg3Cer II3,III3-bis-sulfate; SM1a, Gg4Cer II3-sulfate; SM1b, Gg4Cer IV3-sulfate; SB1a, Gg4Cer II3,IV3-bissulfate; GLC, gas-liquid chromatography; GC-MS, gas chromatography-mass spectrometry; DQF, double quantum filtered; COSY, chemical-shift-correlated spectroscopy; LSIMS, liquid secondary ion mass spectrometry; CID, collision-induced dissociation; MS/MS, tandem mass spectrometry. 相似文献
16.
The human S1-5 gene (fibrillin-like; FBNL) was originally isolated from a subtractively enriched cDNA library established from a subject with Werner syndrome (WS). We isolated genomic clones containing the entire S1-5 gene and determined its genomic structure including the exon–intron organization. The gene spanned approximately 18 kb of genomic DNA and consisted of 12 exons. Its expression was abundant in all tissues examined except brain and peripheral leukocytes, where it was undetectable. In addition, we have mapped S1-5 by fluorescencein situhybridization to chromosome 2p16, a position that excludes it as a candidate for WS. Our data should facilitate an understanding of the function and regulation of S1-5 in human tissues. 相似文献
17.
Isolation and characterization of soybean waste-degrading microorganisms and analysis of fertilizer effects of the degraded products. 总被引:1,自引:0,他引:1 下载免费PDF全文
Two microorganisms which could degrade soybean lees efficiently were isolated and identified as Bacillus circulans and B. stearothermophilus. These two strains secreted thermostable proteases into the medium and could digest soybean lees rapidly and completely at 50 degrees C. Initially, the soybean lees were degraded to proteins in approximately 20 h by these two strains, after which time the concentrations of peptides in the medium gradually increased. The degraded products from soybean lees contained abundant nitrogen compounds, such as peptides, amino acids, and amides. Approximately 10 times more fresh plant weight was obtained (in the case of Brassica campestris) when these degraded products were applied than when water was applied for 42 days. These stimulatory effects of the soybean lees products were almost equal to those of a chemically synthesized fertilizer. 相似文献
18.
Chunyu Cao Hisao Kurazono Shinji Yamasaki Keiko Kashiwagi Kazuei Igarashi Yoshifumi Takeda 《Microbiology and immunology》1994,38(6):441-447
The gene encoding a Verotoxin 2 variant, VTvp1, was mutated by oligonucleotide-directed site-specific mutagenesis. Among 6 mutant toxins encoded by the mutated genes, E167Q-R170L (glutamic acid at position 167 and arginine at position 170 from N-terminus of the A subunit were replaced by glutamine and leucine, respectively) was found to have markedly decreased activities; inhibition of protein synthesis, Vero cell cytotoxicity and mouse lethality of the purified E167Q-R170L were 1/1,900, 1/125,000 and 1/2,000, respectively, of those of the purified wild-type VT2vp1. Since the antigenic property of the E167Q-R170L was demonstrated to be similar to that of the wild-type VT2vp1 by Ouchterlony double gel diffusion test and by neutralization test of Vero cell cytotoxicity of the VT2vp1, a possibility to use the mutant VT2vp1, E167Q-R170L, as a toxoid is discussed. 相似文献
19.
Keiko Miyajima Mamoru Hirata Toshiaki Yoshida Hiroshi Kosaka Akira Okayama 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1994,654(2)
A method for the determination of δ-aminolevulinic acid in plasma of lead-exposed workers by high-performance liquid chromatography with fluorescence detection of a fluorescent δ-aminolevulinic acid derivative (2-methylidineamino-3,5-diacetyl-4,6-dimethylpropionic acid) was established. The detection limit of δ-aminolevulinic acid in plasma was 0.01 μg/ml at a signal-to-noise ratio of 5:1. A linear correlation was obtained between the amounts of δ-aminolevulinic acid injected from 0.01 to 0.5 μg/ml (r = 0.999). The recovery of 0.05 and 0.1 μg/ml of δ-aminolevulinic acid added to plasma with various concentrations of δ-aminolevulinic acid in plasma ranged from 80.0 to 100.8%. This method, combined with the use of an automatic sampler, should facilitate the routine measurement of δ-aminolevulinic acid in plasma. 相似文献
20.
Tetsuo Hashimoto Eiko Otaka Jun Adachi Keiko Mizuta Masami Hasegawa 《Journal of molecular evolution》1993,36(3):282-289
Summary Using - and -hemoglobin sequences, we made a maximum likelihood inference as to the phylogenetic relationship among carnivores, including the two pandas, giant and lesser. Molecular phylogenetic studies up to 1985 had consistently indicated that the giant panda is more closely related to the bear than to the lesser panda. In 1986, however, a contradictory tree was constructed, using hemoglobins and so on, in which the two pandas link together (Tagle et al. 1986). In contrast to that tree, our conclusion supports the close relationship between bear and giant panda. The surface impression of a close relationship between the two pandas drawn from pairwise amino acid differences is explained by a rapid rate of hemoglobin evolution in the bear compared to that in the two pandas.Offprint requests to: T. Hashimoto 相似文献