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71.
72.
Gangliosides isolated from the brain of patients with Creutzfelt-Jakob (C-J) disease were analyzed. The ganglioside current was abnormally low, and the percentage distributions of individual gangliosides and the long-chain base compositions were abnormal. The C20-sphingosine contents of all the ganglioside fractions were low. Abnormalities in ganglioside long-chain bases in adult human brain have been reported previously only in patients with inherited metabolic disorders. These abnormalities in C-J disease seem to be closely related to the cause of the disease. 相似文献
73.
Miura I Tamura A Taniwaki M Nakamura S Nakamine H Yoshino T Ichinohasama R Miura AB 《Cancer Genetics and Cytogenetics》2000,123(2):97-101
The most frequent nonrandom chromosome rearrangements in B-cell non-Hodgkin lymphoma (NHL) is the t(14;18)(q32;q21) found in follicular lymphomas. The t(14;18) in Hodgkin disease (HD) was rarely observed using cytogenetic techniques. Although Southern blot analysis failed to demonstrate the t(14;18), there have been conflicting reports concerning the occurrence of the translocation using polymerase chain reaction (PCR) methods in HD. In some HD tissues, the translocation might be derived from background lymphocytes rather than Hodgkin and Reed-Sternberg (HRS) cells, because B-cells with t(14;18) are regularly generated in normal individuals. However, the cells bearing the translocation have remained unidentified. We describe a patient with HD who showed t(14;18) in hyperdiploid cells using fluorescence in situ hybridization (FISH) and HRS cells which were strongly positive for BCL2 by immunohistochemistry. These findings suggest that HRS cells may have a t(14;18). 相似文献
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75.
Masahiro Yamashita Anat Achiron Tomoyuki Miura Jun Takehisa Eiji Ido Tatsuhiko Igarashi Kentaro Ibuki Mitsuhiro Osame Shunro Sonoda Eldad Melamed Prof. Masanori Hayami Batya Shohat 《Virus genes》1995,10(1):85-90
A new endemic focus of human T-lymphotropic virus type I (HTL V-I) was recently reported among Mashhadi Jews, a group of immigrants from northeastern Iran to Israel. We extracted DNAs from fresh peripheral blood mononuclear cells (PBMCs) and/or gargle mouthwash from 10 HTL V-I carriers, who consisted of members of one family, and HTL V-I-associated myelopathy (HAM) and adult T-cell leukemia (ATL) patients. Long terminal repeat (LTR) regions of proviral DNAs were sequenced and analyzed phylogenetically. In a phylogenetic tree, all the Mashhadi HTL V-I isolates belonged to subtype A, one of the three subtypes of the cosmopolitan type of HTL V-I, and made a tight cluster distinct from the other isolates of subtype A from Japan, India, the Caribbean Basin, and South America. Although a few nucleotide substitutions were observed among the clones sequenced, no characteristic sequence variation was found in different disease manifestations, even in one family or different sources of DNA preparation. 相似文献
76.
A study on the immunopathological similarities between IgA nephropathy and Henoch-Schoenlein purpura (HSP) nephritis is described. Various examinations were performed as follows. (1) Pathological studies: light microscopic findings and immunofluorescent staining; (2) Measurement of the levels of IgA in pharyngeal washings and sera, and those of IgA quantitated by radial immunodiffusion; (3) Elution studies: renal biopsy specimens obtained from patients with IgA nephropathy and HSP nephritis were treated with citrate buffer (pH 3.2) and the "eluate" was neutralized by sodium hydroxide. The "eluate" was then applied to the acid-treated sections obtained from the same and other patients with IgA nephropathy as well as sections from patients with HSP nephritis and other glomerular diseases. The sections were stained with FITC-conjugated heavy chain specific antihuman IgA antisera and then examined with a fluorescent microscope. There were no differences in pathological findings of IgA nephropathy and HSP nephritis in the light microscopic and immunofluorescent examinations. The levels of IgA in pharyngeal washings and sera were significantly increased in patients with both diseases. IgA antibodies deposited in kidneys from patients with HSP nephritis crossreacted with kidneys from some patients with IgA nephropathy, and vice versa. However, antibodies from patients with IgA nephropathy and HSP nephritis did not react with normal glomeruli or other nephritic glomeruli. It is concluded that there are some immunopathological similarities between IgA nephropathy and HSP nephritis. 相似文献
77.
The effect of prednisolone on the substance P (SP)-induced vascular permeability increase in male ddY, WBB6 F1–+/+ (control) and WBB6 F1-W/Wv (no mast cell in skin or internal organs) mice was investigated. 1) SP (1–10 000 pg/site) increased vascular permeability in ddY, WBB6 F1–+/+ and WBB6 F1-W/Wv mice ears. 2) SP (100 pg/site)-induced vascular permeability was inhibited by prednisolone (10 mg/kg) administered intraperitoneally 3 to 12 hours prior to the elicitation of the reaction in ddY mice. When dexamethasone at a dose of 1 mg/kg was administered intraperitoneally 2 to 24 hours prior to the elicitation of the reaction, significant inhibition was observed. When prednisolone was administered intraperitoneally 8 hours prior to the elicitation of the reaction, the SP-induced capillary permeability increase in both ddY and WBB6 F1-W/Wv mice was clearly inhibited by the drug at doses of 5 and 10 mg/kg. 3) Diphenhydramine (1 and 10 mg/kg) inhibited SP-induced vascular reaction in ddY mice but not in WBB6 F1-W/Wv mice. 4) Atropine (10 mg/kg) inhibited SP-induced vascular reaction in both ddY and WBB6 F1-W/Wv mice. But acetylcholine did not cause an increase of vascular permeability in ddY and WBB6 F1-W/Wv mice ears. 5) Prednisolone (5 mg/kg) inhibited histamine- and serotonin-induced vascular permeability in ddY and WBB6 F1-W/Wv mice ears. 6) Prednisolone (5 and 10 mg/kg) inhibited the SP-induced histamine release from ddY mice peritoneal mast cells. These results suggest that the vascular effect of SP is mediated by both mast cell dependent (release of histamine from mast cells) and mast cell independent mechanisms. Prednisolone inhibits the SP-induced vascular permeability mediated by both mechanisms in mice. 相似文献
78.
Hess AD Thoburn C Chen W Miura Y Van der Wall E 《Clinical immunology (Orlando, Fla.)》2001,101(1):67-76
The N-terminal flanking region of the invariant chain peptide termed CLIP appears to have superagonistic properties interacting with the T cell receptor and the MHC class II molecule at or near the binding site for the bacterial superantigen Staphylococcal enterotoxin B (SEB). The present studies explored the hypothesis that the N-terminal segment of CLIP can augment the immunogenicity of cryptic "self" tumor-associated antigens. A chimeric construct of an MHC class II binding peptide from the c-erb oncogene (Her-2/neu) containing the N-terminal flanking region of CLIP elicited potent antitumor activity against a Her-2/neu-positive tumor in a rat model system. Comparatively, the unmodified parent peptide was ineffective. The induction of effective antitumor immunity, however, required presentation of the chimeric peptide construct on irradiated tumor cells or the peptide construct in concert with a Her-2/neu MHC class I-restricted peptide from Her-2/neu. As revealed by adoptive transfer studies, effective protective antitumor immunity in this setting required the CD4 T helper subset. Additionally, in vitro analysis revealed that immunization with the parent peptide resulted in a weak immune response to the unmodified peptide consisting of both type 1 (IL-2, IFN-gamma) and type 2 (IL-4, IL-10) cytokine-producing cells analyzed by RT-PCR (qualitative and quantitative) and by limiting dilution assay. Comparatively, immunization with the chimeric construct elicited a potent immune response to the parent peptide with predominantly type 1 cytokine-producing cells. Taken together, the results suggest that immunization with the chimeric Her-2/neu peptide induced protective antitumor immunity. Associated with this immunization strategy was the enhancement of a type 1 cytokine response. 相似文献
79.
Mechanical stress enhances expression and production of plasminogen activator in aging human periodontal ligament cells 总被引:1,自引:0,他引:1
Plasminogen activator (PA) converts plasminogen to plasmin, and plasmin activates the kinin cascade and latent extracellular matrix metalloproteases. The periodontal ligament serves to anchor the tooth to the alveolus and functions as a cushion between these hard tissues to migrate occlusal force during mastication. We reported previously that repeated mechanical tension force (MTF) as an experimental model of a traumatic occlusion, increased PA activity in human periodontal ligament derived fibroblast (hPLF) cells. In this study, the influence of in vitro cellular aging on MTF-stimulated PA activity in hPLF cells was studied. Aged hPLF cells produced a significantly higher PA activity when compared with those of young hPLF cells in response to MTF in a time- and magnitude-dependent manner. tPA mRNA levels in aged cells were higher than those in young cells, whereas PAI-1 mRNA remained unchanged and uPA mRNA was not detected. Because MTF-stimulated PA activity from hPLF cells was increased by in vitro cellular aging, aging of the periodontal ligament may affect the severity of the inflammation and the degradation of the extracellular matrix of periodontal ligament tissue by producing a large amount of PA in response to excessive force such as a traumatic occlusion. 相似文献
80.