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131.
132.
Analysis of risk epitopes of anti-neutrophil antibody MPO-ANCA in vasculitis in Japanese population 总被引:1,自引:0,他引:1
Suzuki K Kobayashi S Yamazaki K Gondo M Tomizawa K Arimura Y Nakabayashi K Ozaki S Yoshida M Yoshida T Tsusaka N Muso E Okazaki T Hashimoto H 《Microbiology and immunology》2007,51(12):1215-1220
Autoantibodies to myeloperoxidase (MPO) are a subset of anti-neutrophil cytoplasmic antibody (ANCA, MPO-ANCA) detected in the sera of some patients with primary systemic vasculitis. The titer of MPO-ANCA does not always reflect disease activity and this inconsistency may be attributable to differences in epitopic specificity by MPO-ANCA among various patients with vasculitis. Epitope analysis may also explain the occurrence of MPO-ANCA in different vasculitic syndromes. We screened the sera of 148 MPO-ANCA positive patients from six vasculitic syndromes: rapidly progressive gromerulonephritis (RPGN), microscopic polyangiitis (MPA), idiopathic crescentic glomerulonephritis (I-CrGN), classic polyangiitis nodosa (cPAN), Churg-Strauss syndrome (CSS), Kawasaki disease (KD); and from patients with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). The sera were collected by the Intractable Vasculitis Research Project Group in Japan. No serum showed epitopes La and Lb of light chain of MPO, and sera with 68.6% of patients showed a positive reaction to one or more epitopes in heavy chain of MPO. Analysis of binding level showed that RPGN, I-CrGN and MPA sera mainly reacted to the Ha epitope at the N-termimus of the MPO heavy chain, CSS sera reacted to Ha and the Hf epitope close to the C-terminus of the MPO heavy chain, KD reacted mainly to Hf, while SLE and RA sera reacted to all epitopes. These results suggest that MPO-ANCA recognizing specific regions of the N-terminus of the MPO H-chain confer an increased risk of vasculitis RPGN, I-CrGN, MPA and CSS. Furthermore, the epitopic specificity of MPO-ANCA differentiates vasculitic from non-vasculitic syndromes associated with MPO-ANCA positivity and differentiates in the cirtain type of vasculitis from various vasculitic syndromes. In particular, vasculitic syndromes associated with kidney involvement had similar epitopic reactivity which suggests that this pattern confers an increased risk of vasculitis. 相似文献
133.
Tanabe H Ito H Sugiyama K Kiriyama S Morita T 《Bioscience, biotechnology, and biochemistry》2007,71(2):575-578
Changes in the small intestinal mucin contents in rats were evaluated by two methods, viz., a newly established ELISA and a method based on the measurement of O-linked oligosaccharide chains (OSC) as a mucin marker. Significant correlation was observed between the values of ELISA-derived mucins and OSC. The results confirm the usefulness of measurement of OSC as an alternative method for mucin determination. 相似文献
134.
Kongrit D Jisaka M Iwanaga C Yokomichi H Katsube T Nishimura K Nagaya T Yokota K 《Bioscience, biotechnology, and biochemistry》2007,71(2):491-498
A plant allene oxide synthase (AOS) reacting with 13S-hydroperoxy-9Z,11E,15Z-octadecatrienoic acid (13-HPOT), a lipoxygenase product of alpha-linolenic acid, provides an allene oxide which functions as an intermediate for jasmonic acid (JA) synthesis, making AOS a key enzyme regulating the JA level in plants. Although AOSs in various plants have been investigated, there is only limited information about AOSs in soybean (Glycine max). In this study, we cloned and characterized two soybean AOSs, GmAOS1 and GmAOS2, sharing 95% homology in the predicted amino acid sequences. GmAOS1 and GmAOS2 were composed of 564 and 559 amino acids respectively, with predicted N-terminal chloroplast-targeting signal peptides. Both AOSs expressed in Escherichia coli were selective for 13S-hydroperoxides of alpha-linolenic and linoleic acids, suggesting the potential of GmAOS1 and GmAOS2 to contribute to JA synthesis. GmAOS1 and GmAOS2 were expressed in leaves, stems, and roots, suggesting broad distribution in a soybean plant. 相似文献
135.
Enzymatic activities of uridine and thymidine phosphorylase in normal and cancerous uterine cervical tissues 总被引:1,自引:0,他引:1
Kobayashi Y Wada Y Ohara T Okuda Y Suzuki N Hasegawa K Kiguchi K Ishizuka B 《Human cell》2007,20(4):107-110
In this study, the preliminary analyses were conducted of enzymatic activities of uridine phosphorylase (UP) and thymidine phosphorylase (TP) in normal tissues and cancer tissues of the uterine cervix. The study was performed on 27 patients of cervical cancer, treated first in our hospital. Normal cervical tissues obtained from 15 patients undergoing hysterectomy for benign diseases were used as controls. The supernatant of the homogenated cervical tissues and the stroma (5-FU and ribose-1-P or deoxyribose-1-P) were analyzed by high performance liquid chromatography, and then the UP and TP activities calculated. TP activity was significantly greater than UP activity (P < 0.0001). Both UP and TP showed significantly greater activity in cancer tissues than in normal tissues (P < 0.0001). In the TP activity of the cancer tissues, there was no significant difference among the histological types, while the TP activity tended to be significantly higher in the cases with lymph node metastasis. These results showed that the TP-mediated route seemed important as the 5FU metabolic pathway in the uterine cervical tissues, and TP enzymatic activity might be associated with lymph node metastasis. 相似文献
136.
Tanabe S Kinuta Y Yasumatsu H Takayanagi M Kobayashi S Takido N Sugiyama M 《Bioscience, biotechnology, and biochemistry》2007,71(11):2852-2855
We evaluated the effects of a 50% methanol extract of Citrus unshiu powder (MEC) on cytokines in peripheral blood mononuclear cells (PBMCs) obtained from patients with seasonal allergic rhinitis to cedar pollen. The levels of cytokines, such as TNF-alpha, IFN-gamma, IL-2, IL-4, IL-5, IL-10, IL-12 (p70), IL-13, and GM-CSF, produced by pollen-stimulated PBMC were measured. We found that MEC suppressed pollen-induced TNF-alpha release and increased IFN-gamma release from PBMCs. The results suggest that Citrus unshiu powder has an immunomodulatory effect in vitro and that its use could improve seasonal allergic rhinitis symptoms. 相似文献
137.
A new member of archaeal DNA polymerase from Pyrococcus furiosus was crystallized. Diffraction data to 3.1 A of the selenomethionine-derivatized crystal were collected, and preliminary crystallographic study has been completed. The crystal belongs to the space group C2 with unit cell parameters of a = 93.2 A, b = 124.9 A, c = 87.7 A, alpha = 90 degrees , beta = 109.7 degrees , and gamma = 90 degrees . Assuming the presence of one molecule in the asymmetric unit, the solvent content of the crystal is estimated to be 54%, corresponding to a Matthews coefficient V(M) of 2.7A (3) Da(-1). 相似文献
138.
Sakihama N Nakamura M Palanca AA Argubano RA Realon EP Larracas AL Espina RL Tanabe K 《Parasitology international》2007,56(3):185-194
Allelic diversity of the Plasmodium falciparum merozoite surface protein 1 gene (msp1) is mainly generated by meiotic recombination at the mosquito stage. We investigated recombination-based allelic diversity of msp1 in a P. falciparum population from Palawan Island, the Philippines, where malaria transmission is moderate. We identified the 5' recombinant types, 3' sequence types and msp1 haplotypes (unique combinations of 5' recombinant type and 3' sequence type), and compared them with those of P. falciparum from the Solomon Islands, where malaria transmission is high. The mean number of 5' recombinant types per patient in Palawan was 1.44, which is comparable to the number for the Solomon Islands (1.41). The Palawan parasite population had 15 msp1 haplotypes, whereas the Solomon Islands population had only 8 haplotypes. The Palawan population showed strong linkage disequilibrium between polymorphic blocks/sites within msp1, which is comparable to the results for the Solomon Islands. These findings support our hypothesis that the extent of allelic diversity of msp1 is determined not only by the transmission intensity but also by the number of msp1 alleles prevalent in the local parasite population and the extent of mixed-allele infections. Contribution of a high prevalence of the chloroquine (CQ)-sensitive allele of P. falciparum CQ resistance transporter (pfcrt) to the relatively high msp1 diversity in the Palawan population is discussed. 相似文献
139.
Japan is one of a small number of countries to have successfully controlled or eliminated major parasitic diseases, including malaria, filariasis, schistosomiasis and enteric parasitoses. Of particular importance in this success was a close collaboration between primary research and public health efforts. Many Japanese researchers continue to study malaria, particularly the areas of genetics and immunology, and this should contribute to global parasite eradication strategies. Furthermore, studies of immunoregulation of nematode infection using the interleukin-18 pathway, most of which have been conducted in Japan, are helping to improve researchers' understanding of human immune mechanisms and host-parasite interactions. 相似文献
140.
Moriyama A Kii I Sunabori T Kurihara S Takayama I Shimazaki M Tanabe H Oginuma M Fukayama M Matsuzaki Y Saga Y Kudo A 《Genesis (New York, N.Y. : 2000)》2007,45(2):90-100
In the past decades, the function of the Wnt canonical pathway during embryogenesis has been intensively investigated; however, little survey of neonatal and adult tissues has been made, and the role of this pathway remains largely unknown. To investigate its role in mature tissues, we generated two new reporter transgenic mouse lines, ins-TOPEGFP and ins-TOPGAL, that drive EGFP and beta-galactosidase expression under TCF/beta-catenin, respectively. To obtain the accurate expression pattern, we flanked these transgenes with the HS4 insulator to reduce chromosomal positional effects. Analysis of embryos showed that the reporter genes were activated in regions where canonical Wnt activity has been implicated. Furthermore, their expression patterns were consistent in both lines, indicating the accuracy of the reporter signal. In the neonatal brain, the reporter signal was detected in the mesencephalon and hippocampus. In the adult mice, the reporter signal was found in the mature pericenteral hepatocytes in the normal liver. Furthermore, during inflammation the number of T cells expressing the reporter gene increased in the adult spleen. Thus, in this research, we identified two organs, i.e., the liver and spleen, as novel organs in which the Wnt canonical signal is in motion in the adult. These transgenic lines will provide us broader opportunities to investigate the function of the Wnt canonical pathway in vivo. 相似文献