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81.
Microanatomical localization of PD-1 in human tonsils 总被引:3,自引:0,他引:3
PD-1 is an immunoinhibitory receptor, which belongs structurally to the CD28 family. PD-1-deficient mice show breakdown of peripheral tolerance and manifest multiple autoimmune symptoms. We previously described expression of PD-1 on activated T and B lymphocytes and myeloid cells. However, little is known about the microanatomical distribution of PD-1 in lymphoid organs. In this study, we performed immunohistochemistry using monoclonal antibodies against human PD-1. In human tonsils, PD-1 was expressed on most of T cells and a small subset of centrocytes in the light zone of germinal centers (GCs), where clonal selection of centrocytes takes place. These results suggest that PD-1 may play an important role in GC reaction. 相似文献
82.
Human Disease Genes and Their Cloned Mouse Orthologs: Exploration of the FANTOM2 cDNA Sequence Data Set
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83.
84.
Jun-Ichi Adachi Masayuki Shiseki Tomoko Okazaki Gosei Ishimaru Masayuki Noguchi Setsuo Hirohashi Jun Yokota 《Genes, chromosomes & cancer》1995,14(4):301-306
Fifty-seven primary lung carcinomas and 35 metastatic lung carcinomas were analyzed for microsatellite instability at 11 different chromosomal loci. Although no instability was detected in 37 small cell lung carcinomas (SCLC), it was frequently detected in non-small cell lung carcinomas (NSCLC) (16/55, 29%). In NSCLC, the incidence of replication errors (RERs) in metastatic tumors (12/22, 55%) was significantly higher than that in primary tumors (4/33, 12%) (P = 0.0021). Among 10 pairs of primary tumors and corresponding metastases, there were 4 cases which manifested the identical RER phenotypes in both primary and metastatic tumors. In two cases, RER phenotypes were detected in metastatic but not in primary tumors. Never was an RER phenotype found only in a primary tumor but not in the metastases. RERs were detected more frequently in stage III or IV tumors (3/8, 38%) than stage I or II tumors (1/25, 4%) (P = 0.0359). Tumor cells with allelic losses on chromosome arm 3p or 18q tended to have RER phenotypes (P = 0.0432 and P = 0.0187, respectively). The data suggest that microsatellite instability is common in NSCLC but not in SCLC, and that genomic instability appears late in tumor progression and plays an important role in the acquisition of more malignant phenotypes in NSCLC. 相似文献
85.
For reconstruction and regeneration of hard tissues, scaffold biomaterials with large size pores and high porosity are important, in addition to their roles as supporting frames. To develop a new biodegradable scaffold biomaterial, CO3Ap, which has crystallinity and a chemical composition similar to bone, was synthesized at pH 7.4 and 60 degrees C. Then, the CO3Ap was mixed with a neutralized collagen gel and the CO3Ap-collagen mixtures with different kinds of CO3Ap contents and porosity were lyophilized into sponges. Scanning electron micrography (SEM) observation of CO3Ap-collagen sponges showed favorable pores for cell invasion. Approximately 50-300 microm size pores appeared to continue through the bulk. Higher magnification of the sponge showed a better adhesion between CO3Ap crystals and collagen. X-ray high-resolution microtomography revealed a clear image of the 3D structure of the sponges. The porosity of 0, 70 and 90%(w/w) CO3Ap-collagen sponges was 79.2 +/- 2.8%, 72.6 +/- 2.4% and 48.9 +/- 6.1%, respectively. The 70%(w/w) CO3Ap-collagen sponge appeared to be the most favorable biomaterial from the viewpoint of natural bone properties. Mouse osteoblast MC3T3-E1 cells were cultured in alphaMEM with 10% FCS for 2 weeks. Hematoxylin-eosin staining confirmed osteoblast cells invaded well into the CO3Ap-collagen sponge. These sponges are expected to be used as hard tissue scaffold biomaterials for therapeutic uses. 相似文献
86.
G Saigo R Ryo Y Nakaya N Yamaguchi R Ryo K Saigo K Ueda 《Rinsho byori. The Japanese journal of clinical pathology》1986,34(12):1417-1421
87.
Okazaki K Takada A Ito T Imai M Takakuwa H Hatta M Ozaki H Tanizaki T Nagano T Ninomiya A Demenev VA Tyaptirganov MM Karatayeva TD Yamnikova SS Lvov DK Kida H 《Archives of virology》2000,145(5):885-893
Summary. Influenza A viruses of different subtypes were isolated from fecal samples of ducks in their nesting areas in Siberia in
summer from 1996 to 1998. Phylogenetic analysis of the NP genes of the isolates in Siberia and those in Hokkaido, Japan on
their flyway of migration from Siberia to the south in autumn revealed that they belong to the Eurasian lineage of avian influenza
viruses. It is noted that the genes of the isolates in Siberia are closely related to those of H5N1 influenza virus strains
isolated from chickens and humans in Hong Kong in 1997 as well as to those of isolates from domestic birds in southern China.
The results indicate that influenza viruses perpetuated in ducks nesting in Siberia should have contributed genes in the emergence
of the H5N1 virusin Hong Kong. Vaccine prepared from avirulent A/duck/Hokkaido/4/96 (H5N3) influenza virus was potent enough
to protect mice from challenge with lethal dose of the pathogenic H5N1 virus [19]. Intensive surveillance study of aquatic
birds especially in Siberia is, therefore, stressed to provide information on the future pandemic influenza virus strains
and for vaccine preparation.
Received August 24, 1999/Accepted January 7, 2000 相似文献
88.
T Mochizuki Y Izumi Y Kato T Okazaki M Tashima O Nagauchi H Sawada H Uchino 《Journal of Japan Haematological Society》1987,50(6):1183-1189
89.
Takaaki Ohmori Ryo Tabei Keiji Fukui Kazuhiko Sadamoto Saburo Sakaki 《Pathology international》1989,39(3):190-194
Two cases of meningioma revealing conspicuous plasmo lymphocytic tissue and hyalinized fibrous tissue components are reported. Histopathological examination of the plasmo lymphocytic infiltration was performed. Both lesions showed polyclonality of plasma cells as revealed by positive reactions for 1gG and paraimmunoglobulin χ- and λ light chains, and amyloid infiltration into the fibrous stroma and blood vessel walls. The histochemical and immunohistochemical characteristics of the lesion in relation to its etiology are briefly discussed. Acta Pathol. Jpn. 32: 190∼194, 1989. 相似文献
90.
Hasebe R Kimura T Sato E Okazaki K Ochiai K Wada R Umemura T 《Journal of comparative pathology》2002,127(2-3):118-125
Little is known about the neuropathogenicity of equine herpesvirus-1 (EHV-1) in mice. No neurological signs were observed in 6-day-old mice inoculated intracerebrally with the HH1 strain (HH1) of EHV-1. However,6-day-old mice inoculated intracerebrally with a variant derived by serial passage of HH1 in mouse brain showed severe neurological symptoms and eventually died. Histological analyses were performed on 6-day-old mice inoculated with the neuroadapted HH1 (NHH1) and the parental HH1 strain by the intracerebral, intranasal or intraperitoneal route. All routes of inoculation with NHH1 caused encephalitis, but myelitis was observed only in mice inoculated intraperitoneally. Prominent histological findings were perivascular cuffing sometimes associated with small fibrin thrombi, neuronal and glial degeneration and necrosis, and intranuclear inclusion bodies in neurons, glial cells and ependymal cells. Intracerebral and intranasal inoculation, but not intraperitoneal inoculation, with HH1 induced central nervous system (CNS) lesions that were milder than those in mice inoculated with NHH1. The distribution of viral antigen was more widespread in mice inoculated with NHH1 than with HH1. No viral antigen was detected in the CNS of mice inoculated intraperitoneally with HH1. These results indicate that increased viral multiplication and spreading in the CNS were responsible for the enhanced neurovirulence of NHH1. Although EHV-1 has been considered to be primarily endotheliotropic in horses, both NHH1 and HH1 showed tropism for the parenchymal cells of the CNS in mice, namely neurons, glial cells and ependymal cells. 相似文献