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Structural studies of a human gamma 3 myeloma protein (Jir) bearing the allotypic marker Gm(st) 总被引:2,自引:0,他引:2
H Matsumoto S Ito T Miyazaki T Ohta 《Journal of immunology (Baltimore, Md. : 1950)》1983,131(4):1865-1870
The authors established the amino acid substitutions determining G3m(s) and G3m(t) specificities, which characterize Mongoloid populations, by sequence analysis of the Fc region of a myeloma protein (Jir). By comparing the amino acid sequences of the IgG3 (Jir) and the other IgG subclasses analyzed to date, it was found that G3m(s) was an isoallotype specified by an amino acid substitution at position 435; i.e., whereas the subclasses IgG1, IgG2, and IgG4 had histidine in common, G3m(s-) had arginine in this position. This was also confirmed by the observation that the Fc fragment in question bound to protein A. It was also established that the amino acid at position 379 of G3m(t-) IgG3 and the other subclasses was valine, whereas methionine in this position was specific for G3m(t+). In addition, the amino acids at position 339 of G3m(u-) IgG3 Jir was threonine, and at position 296 of G3m(g-) IgG3 Jir was tyrosine. These findings are not in accord with the hitherto postulated relations of alanine and phenylalanine to G3m(u-) and G3m(g-), respectively. Finally, this study showed that a large number of substitutions occurred at positions 384 through 389, which suggests that many specificities of the G3m(b) group occur on IgG3 proteins. 相似文献
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The subsection Magnicellulatae of the genus Podosphaera section Sphaerotheca belongs to the tribe Cystotheceae of the Erysiphaceae, which has the characteristic of producing catenate conidia with distinct
fibrosin bodies. In this study, we newly determined the nucleotide sequences of the D1/D2 domains of the 28S rDNA region and
the sequences of the rDNA internal transcribed spacer (ITS) region to investigate the relationships between the phylogeny
of this fungal group and their host plants. The results indicated that the 28S rDNA region is too conservative for phylogenetic
analysis of this fungal group. The phylogenetic analysis using 95 ITS sequences demonstrated that two or more Magnicellulatae taxa often infect the same plant genus or species. Although there is a close relationship between Magnicellulatae and asteraceous hosts, this association seems to be not as strict as that between Golovinomyces and the Asteraceae. The difference between the two fungal groups may be explained by their different evolutionary timing. 相似文献
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Satonori Kurashige Kouichi Kitamura Kiyoto Akama Susumu Mitsuhashi 《Microbiology and immunology》1970,14(1):41-47
An immune ribonucleic acid (RNA) preparation was extracted with phenol from the spleens of guinea pigs immunized with diphtheria toxoid. Antibody-carrying cells were detected by immunocyte adhesion as rosette-forming cells. When germ-free rats, conventional guinea pigs or mice were injected intraperitoneally with this preparation, the rosette-formers were detected in either peritoneal exudate cells or spleen cells, whereas serum antibodies were unable to be detected thus far in such animals. Two injections with this preparation did not cause any remarkable increase in the number of rosette-formers, and serum antibody was also not detectable. By contrast, a high titer of serum antibody was demonstrated and the number of rosette-formers increased shortly after an injection of a small amount of diphtheria toxoid into guinea pigs which had previously received an injection with immune RNA. This reaction indicates a secondary response of antibody formation. However, secondary responses were not induced by injections of immune RNA preparations in guinea pigs primed with either diphtheria toxoid or immune RNA preparation. These facts suggest that immune RNA preparations did not contain antigens or fragments thereof and the immune response induced by RNA preparation is not the same as that induced by stimulation by the antigen itself. These results moreover can be accounted for by the notion that the immune RNA preparation is able to induce “memory” cells capable of responding to a secondary stimulus with an antigen and producing a high titer of serum antibody. 相似文献
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Yasutaka Fushimi Tomohisa Okada Yasushi Takagi Takeshi Funaki Jun C. Takahashi Susumu Miyamoto Kaori Togashi 《PloS one》2016,11(2)
Moyamoya disease (MMD) is a chronic, progressive, cerebrovascular occlusive disease that causes abnormal enlargement of collateral pathways (moyamoya vessels) in the region of the basal ganglia and thalamus. Cerebral revascularization procedures remain the preferred treatment for patients with MMD, improving the compromised cerebral blood flow (CBF). However, voxel based analysis (VBA) of revascularization surgery for MMD based on data from pre- and postoperative data has not been established. The latest algorithm called as Diffeomorphic Anatomical Registration Through Exponentiated Lie Algebra (DARTEL) has been introduced for VBA as the function of statistical parametric mapping (SPM8), and improved registration has been achieved by SPM8 with DARTEL. In this study, VBA was conducted to evaluate pre- and postoperative single photon emission computed tomography (SPECT) images for MMD by SPM8 with DARTEL algorithm, and the results were compared with those from SPM8 without DARTEL (a conventional method). Thirty-two patients with MMD who underwent superficial temporal artery-middle cerebral artery (STA-MCA) bypass surgery as the first surgery were included and all patients underwent pre- and postoperative 3D T1-weighted imaging and SPECT. Pre- and postoperative SPECT images were registered to 3D T1-weighted images, then VBA was conducted. Postoperative SPECT showed more statistically increased CBF areas in the bypassed side cerebral hemisphere by using SPM8 with DARTEL (58,989 voxels; P<0.001), and increased ratio of CBF after operation was less than 15%. Meanwhile, postoperative SPECT showed less CBF increased areas by SPM8 without DARTEL. In conclusion, VBA was conducted for patients with MMD, and SPM8 with DARTEL revealed that postoperative SPECT showed statistically significant CBF increases over a relatively large area and with at most 15% increase ratio. 相似文献
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[6, 7-3H]-17beta-Estradiol-3-glucosiduronate, [6, 7-3H]-estrone-3-glucosiduronate or [6, 7-3H]-estrone was administered intravenously into the rabbit, and analysis and identification of the urinary metabolites were carried out. In either case, the major urinary metabolite was found to be a diconjugate. The sequential enzymic hydrolysis indicated that this diconjugate was glucosiduronate-N-acetyglucosaminide of 17alpha-estradiol. From these results, the conversion of the estrogen glucosiduronate into a diconjugate was thought a rather universal phenomenon in the rabbit. 相似文献
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