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91.
Lymphokine activity production in graft-versus-host reactions across minor histocompatibility antigen barriers. 总被引:1,自引:0,他引:1 下载免费PDF全文
M Hirokawa H Takatsu A Ohshima A Chubachi K Kudo H Niitsu T Takahashi K Yoshida A B Miura 《Clinical and experimental immunology》1989,77(3):434-439
Activated T cells responding to murine minor histocompatibility antigens (HA) were characterized according to the patterns of lymphokine activity production. Although B10.D2/nSN and BALB/c are mutually non-reactive in mixed lymphocyte reaction (MLR), graft-versus-host reaction (GVHR) can be induced by the injection of a large amount of B10.D2/nSN lymphoid cells into irradiated BALB/c recipient mice. Spleen cells from such GVHR mice spontaneously produced interleukin 3 (IL-3)-dependent cell-stimulating activity in cultures, but did not produce interleukin 2 (IL-2). Normal B10.D2/nSN spleen cells also produced IL-3-like activity, but not IL-2 in MLR supernatants, in response to irradiated BALB/c splenocytes. In addition, B-cell stimulatory factor-1 (BSF-1)/interleukin 4 (IL-4) and colony-stimulating factor (CSF) activity were detected in MLR supernatants. The properties of the produced lymphokine activities were similar to those produced in syngeneic transplant mice and syngeneic MLR, but a difference in the time course of lymphokine production existed between GVHR and syngeneic transplant mice. These results indicate that T cells may be activated in vivo in allogeneic transplantation when the donor and the recipient are matched for major HA, and are non-reactive in MLR. Also, the character of lymphokine-producing T cells activated by minor HA may not be qualitatively different from those responding to irradiated syngeneic cells. 相似文献
92.
Yukio Nishimoto Tsukasa Iwahashi Toru Nishihara Hiroyuki Katayama Koichi Kueibayashi Toshihiko Takao Koji Saito 《Pathology international》1987,37(1):155-166
An autopsy case of hepatitis associated aplastic anemia was presented. A 58-year-old Japanese female with non-A, non-B hepatitis was admitted on August 2, 1983. Moderate grade of fever and hemorrhagic diathesis appeared on September 16, when hepatitis was evaluated as being under resolving. The peripheral blood and bone marrow findings were consistent with aplastic anemia. Since infection was suggested by increased levels of serum gamma-globulin and CRP, treatment with antibiotics as well as prednisolone and blood transfusion was initiated. Since September 21, gradual tenderness and edema on the right lower abdominal wall appeared. She died on October 3.
On postmortem examination, systemic plasmacytosis with lymphadenopathy and septic monilial infection was revealed. Numerous plasma cells were atypical, but were immunohistochemically proved to be polyclonal. The bone marrow showed a massive and diffuse plasma cell proliferation with extremely scarce myeloid cells and megakaryocytes. There was a large granulomatous lesion with monilial infection in the wall of the ileocecum. By these findings, systemic plasmacytosis was suspected to be due to chronic monilial infection.
The pathogenesis of systemic plasmacytosis in aplastic anemias and in other diseases were discussed with relation to the present case. 相似文献
On postmortem examination, systemic plasmacytosis with lymphadenopathy and septic monilial infection was revealed. Numerous plasma cells were atypical, but were immunohistochemically proved to be polyclonal. The bone marrow showed a massive and diffuse plasma cell proliferation with extremely scarce myeloid cells and megakaryocytes. There was a large granulomatous lesion with monilial infection in the wall of the ileocecum. By these findings, systemic plasmacytosis was suspected to be due to chronic monilial infection.
The pathogenesis of systemic plasmacytosis in aplastic anemias and in other diseases were discussed with relation to the present case. 相似文献
93.
Kazuhiko Yasuml Rong-Jun Guo Hiroyuki Hanai Hajime Arai Eizo Kaneko Hiroyuki Konno Selichi Takenoshita Koichi Hagiwara Haruhiko Sugimura 《Pathology international》1998,48(2):134-137
A new mutation in the serine-threonine klnase domain of the transforming growth factor β type II receptor (TGFpRII) was found in a case of diffuse, B cell non-Hodgkin's lymphoma of the stomach. A mfssense mutation (ACA to GCA, Thr to Ala) was detected In exon 5, and a wild type allele was also present. This Is the first naturally occurring mutation in the klnase domain of this gene identified in human primary lymphoma. The replication error at three loci was negative, and the poly A tract of exon 3, which is frequently a target of mismatch repair genes, was intact. Malignant lymphoma of B cell origin in the stomach Is an addition to an expanding catalogue of tumors with TGFβRII alterations, and the biological sequelae of the change in the functional domain and the clinical characteristics of the patient in this study are intriguing. 相似文献
94.
Nakano Y Nagamatsu Y Ohshima Y 《Genes to cells : devoted to molecular & cellular mechanisms》2004,9(9):773-779
Mechanisms involved in the control of body size are largely unknown. In the nematode C. elegans, several small body size mutants were isolated, and the responsible genes were reported to encode putative components of a TGFbeta signalling pathway. Recently, mutants in the egl-4 gene encoding cGMP-dependent protein kinases were found to have a larger body size, and it was suggested that EGL-4 down-regulates the TGFbeta/DBL-1 pathway. We show that a permeable cGMP analogue 8-Br-cGMP significantly reduces body size of the wild-type but not that of an egl-4 mutant, indicating that cGMP controls body size through EGL-4. Laser ablation of germ-line cells revealed that a germ-line signal and EGL-4 function in the same pathway. Targeted expression of EGL-4 indicates that EGL-4 can function in hypodermis, neurones and intestine both cell-autonomously and cell-nonautonomously to control organ and body size. We propose a signal cascade for the control of body size that involves a germ-line signal, cGMP, G-kinase EGL-4 and DBL-1/TGFbeta pathway. It is interesting that two important pathways involving cGMP and TGFbeta, respectively, are related. Also, the results suggest a novel mechanism for the control of organ and body size in which hypodermis plays a key role 相似文献
95.
Shiro Ohshima Yukihiko Saeki Toru Mima Mitsuko Sasai Katsuhiro Nishioka Hiroshi Ishida Masatoshi Shimizu Masaki Suemura Richard McCloskey Tadamitsu Kishimoto 《Journal of clinical immunology》1999,19(5):305-313
To investigate the mechanism of the long-lasting efficacy of chimeric monoclonal anti-TNF antibody (cA2) therapy for rheumatoid arthritis (RA), eight patients with refractory RA were treated with a single infusion of cA2 and the changes in circulating cytokines (IL-1, IL-6, TNF, and IL-10), soluble cytokine receptors (TNF-RI, RII, and sIL-6R) and peripheral white blood cell (WBC) subset counts were followed up long-term (12 weeks) after cA2 therapy in them. Significant clinical responses (>20% improvement according to Paulus' criteria) were observed just after cA2 infusion and lasted more than 4 weeks in all patients, as reported elsewhere. Moreover, five of the eight patients showed prolonged clinical responses (>12 weeks). The elevated serum IL-6 and sTNF-RI (or RII) levels before treatment rapidly decreased after treatment. The serum IL-10 levels also significantly elevated before treatment. The elevations of serum IL-10 levels were augmented after treatment and stayed higher than the baseline in four patients with prolonged clinical responses. No significant TNF, IL-1 and -, or sIL-6R were detected in the sera of the patients before treatment and during the whole study period. On the other hand, peripheral lymphocytes as well as total WBC and neutrophils increased for 4 weeks after treatment. However, thereafter, only the lymphocyte count decreased gradually and stayed below the baseline long-term (12 weeks). FACS analysis revealed the predominance of T lymphocytes in the decrease in lymphocyte counts. These results suggest that the augmentation of IL-10 production and the decrease in T cells might partly contribute to the long-lasting efficacy of cA2 treatment in RA. 相似文献
96.
Honma K Abraham JL Chiyotani K De Vuyst P Dumortier P Gibbs AR Green FH Hosoda Y Iwai K Williams WJ Kohyama N Ostiguy G Roggli VL Shida H Taguchi O Vallyathan V 《Human pathology》2004,35(12):1515-1523
We defined mixed-dust pneumoconiosis (MDP) pathologically as a pneumoconiosis showing dust macules or mixed-dust fibrotic nodules (MDF), with or without silicotic nodules (SN), in an individual with a history of exposure to mixed dust. We defined the latter arbitrarily as a mixture of crystalline silica and nonfibrous silicates. According to our definition of MDP, therefore, MDF should outnumber SN in the lung to make a pathologic diagnosis of MDP. In the absence of confirmation of exposure, mineralogic analyses can be used to support the pathologic diagnosis. The clinical diagnosis of MDP requires the exclusion of other well-defined pneumoconioses, including asbestosis, coal workers’ pneumoconiosis, silicosis, hematite miners’ pneumoconiosis, welders’ pneumoconiosis, berylliosis, hard metal disease, silicate pneumoconiosis, diatomaceous earth pneumoconiosis, carborundum pneumoconiosis, and corundum pneumoconiosis. Typical occupations associated with the diagnosis of MDP include metal miners, quarry workers, foundry workers, pottery and ceramics workers, and stonemasons. Irregular opacities are the major radiographic findings in MDP (ILO 1980), in contrast to silicosis, in which small rounded opacities predominate. Clinical symptoms of MDP are nonspecific. MDP must be distinguished from a variety of nonoccupational interstitial pulmonary disorders. 相似文献
97.
Clostridium sordellii phospholipase C: gene cloning and comparison of enzymatic and biological activities with those of Clostridium perfringens and Clostridium bifermentans phospholipase C 下载免费PDF全文
Karasawa T Wang X Maegawa T Michiwa Y Kita H Miwa K Nakamura S 《Infection and immunity》2003,71(2):641-646
The gene encoding Clostridium sordellii phospholipase C (Csp) was cloned and expressed as a histidine-tagged (His-tag) protein, and the protein was purified to compare its enzymatic and biological activities with those of Clostridium perfringens phospholipase C (Cpa) and Clostridium bifermentans phospholipase C (Cbp). Csp was found to consist of 371 amino acid residues in the mature form and to be more homologous to Cbp than to Cpa. The egg yolk phospholipid hydrolysis activity of the His-tag Csp was about one-third of that of His-tag Cpa, but the hemolytic activity was less than 1% of that of His-tag Cpa. His-tag Csp was nontoxic to mice. Immunization of mice with His-tag Cbp or His-tag Csp did not provide effective protection against the lethal activity of His-tag Cpa. These results indicate that Csp possesses similar molecular properties to Cbp and suggest that comparative analysis of toxic and nontoxic clostridial phospholipases is helpful for characterization of the toxic properties of clostridial phospholipases. 相似文献
98.
Nomura H Nishimori H Yasoshima T Hata F Tanaka H Nakajima F Honma T Araya J Kamiguchi K Isomura H Sato N Denno R Hirata K 《Clinical & experimental metastasis》2002,19(5):391-399
To elucidate the mechanisms of metastasis, we established two sublines HPC-1H5 with a highly liver metastatic cell line and
HPC-1P5a with a highly peritoneal disseminating cell line, which were sequentially selected from the parental pancreatic cancer
cell line HPC-1. Using these three cell lines, we investigated several biological properties and mRNA levels of differentially-expressed
genes involved in cancer metastasis by cDNA macroarray. Microscopic findings for the three cell lines were the same. The tumorigenicity,
in vitro growth ability, motile activity, adhesive activity and the production of IL-8 of metastatic sublines were higher than those
of parental HPC-1 cells. Particularly, HPC-1H5 cells showed clearly higher levels of IL-8 expression and tumors of HPC-1H5
cells grew faster and bigger than those of HPC-1P5a cells. In cDNA macroarray analysis of HPC-1H5 cells, 22 genes were up-regulated
and 44 genes were down-regulated compared with parental HPC-1 cells. In HPC-1P5a cells, 9 genes were up-regulated and 28 genes
were down-regulated compared with parental HPC-1 cells. This study provides a demonstration of global gene expression analysis
of pancreatic cancer cells with liver metastasis and peritoneal dissemination. Furthermore, our results provide a new insight
into the study of liver metastasis and peritoneal dissemination of human pancreatic cancer.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
99.
Accumulation of filamentous tau in the cerebral cortex of human tau R406W transgenic mice 总被引:4,自引:0,他引:4 下载免费PDF全文
Ikeda M Shoji M Kawarai T Kawarabayashi T Matsubara E Murakami T Sasaki A Tomidokoro Y Ikarashi Y Kuribara H Ishiguro K Hasegawa M Yen SH Chishti MA Harigaya Y Abe K Okamoto K St George-Hyslop P Westaway D 《The American journal of pathology》2005,166(2):521-531
Missense mutations of the tau gene cause autosomal dominant frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17), an illness characterized by progressive personality changes, dementia, and parkinsonism. There is prominent frontotemporal lobe atrophy of the brain accompanied by abundant tau accumulation with neurofibrillary tangles and neuronal cell loss. Using a hamster prion protein gene expression vector, we generated several independent lines of transgenic (Tg) mice expressing the longest form of the human four-repeat tau with the R406W mutation associated with FTDP-17. The TgTauR406W 21807 line showed tau accumulation beginning in the hippocampus and amygdala at 6 months of age, which subsequently spread to the cortices and subcortical areas. The accumulated tau was phosphorylated, ubiquitinated, conformationally changed, argyrophilic, and sarcosyl-insoluble. Activation of GSK-3beta and astrocytic induction of mouse tau were observed. Astrogliosis and microgliosis correlated with prominent tau accumulation. Electron microscopic examination revealed the presence of straight filaments. Behavioral tests showed motor disturbances and progressive acquired memory loss between 10 to 12 months of age. These findings suggested that TgTauR406W mice would be a useful model in the study of frontotemporal dementia and other tauopathies such as Alzheimer's disease (AD). 相似文献
100.
Hamada K Sasaki T Koni PA Natsui M Kishimoto H Sasaki J Yajima N Horie Y Hasegawa G Naito M Miyazaki J Suda T Itoh H Nakao K Mak TW Nakano T Suzuki A 《Genes & development》2005,19(17):2054-2065
PTEN is an important tumor suppressor gene. Hereditary mutation of PTEN causes tumor-susceptibility diseases such as Cowden disease. We used the Cre-loxP system to generate an endothelial cell-specific mutation of Pten (Tie2CrePten) in mice. Tie2CrePten(flox/+) mice displayed enhanced tumorigenesis due to an increase in angiogenesis driven by vascular growth factors. This effect was partially dependent on the PI3K subunits p85alpha and p110gamma. In vitro, Tie2CrePten(flox/+) endothelial cells showed enhanced proliferation/migration. Tie2CrePten(flox/flox) mice died before embryonic day 11.5 (E11.5) due to bleeding and cardiac failure caused by impaired recruitment of pericytes and vascular smooth muscle cells to blood vessels, and of cardiomyocytes to the endocardium. These phenotypes depend strongly on p110gamma rather than on p85alpha and were associated with decreased expression of Ang-1, VCAM-1, connexin 40, and ephrinB2 but increased expression of Ang-2, VEGF-A, VEGFR1, and VEGFR2. Pten is thus indispensable for normal cardiovascular morphogenesis and post-natal angiogenesis, including tumor angiogenesis. 相似文献