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61.
In an Epstein-Barr virus-transformed human B cell line we found an unusual immunoglobulin heavy chain gene rearrangement. Restriction mapping and sequencing analysis led us to conclude that VH-D and D-JH recombination took place in a single allele. Both VH-D and D-JH complexes still had their recombination signal sequences adjacent and the DNA sandwiched by these two complexes retained a germ line configuration, suggesting the potential for a secondary rearrangement resulting in a VH-D(-D)-JH formation. With this finding, we propose a novel pathway, in which the VH-D complex is an intermediate in the formation of a functional VH exon.  相似文献   
62.
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   
63.
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   
64.
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   
65.
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   
66.
67.
Summary In a study of 277 patients with breast carcinomas, the PAP immunoperoxidase method for demonstrating endogenous estrogen was correlated with the sucrose density gradient (SDG) assay and with histologic and clinical features. The results from the PAP method and SDG assay agreed in 59 of 84 patients (82.1%) on whom both methods were performed. Histologically, the PAP method was positive in 7 of 7 patients with non-invasive carcinomas, in 164 of 233 patients (70.4%) with common invasive ductal carcinoma, and in 21 of 22 of those with special histological types of invasive carcinomas not including Paget's disease, medullary or apocrine carcinoma, where only 5 of 14 were positive. Clinically, 15 of 18 patients with positive endogenous estrogen showed a response to endocrine therapy as opposed to 1 of 9 patients with a negative endogenous estrogen. The mean survival was 31.2 and 15.6 months, respectively for patients with positive and negative endogenous estrogen. Remission for longer than 2 years was seen more often in patients with positive endogenous estrogen. These results suggest a clinical utility of the present PAP method which, therefore, deserves a further trial as an alternative to histochemical methods aiming at the estrogen receptors.This work was supported by Grants-in Aid for Scientific Research from the Ministry of Education, Science, and Culture of Japan (No. 56480119).This paper was presented at the 72nd Annual Meeding of International Academy of Pathology (United States-Canadian Division), Atlanta, Georgia, March 1, 1983.  相似文献   
68.
A case of multicentric malignant fibrous histiocytoma of the stomach and small intestine is reported. The patient was a 60-year-old man who had total gastrectomy under an impression of a gastric carcinoma. The resected stomach revealed a large polypoid mass in the antral portion at the greater curvature. Three months later, he developed ileus and an 80 cm segment of the jejunum was removed. It contained two polypoid masses identical to that seen in the stomach. The tumors showed, in addition to the characteristic light microscopic appearances, strong positivity for alpha-1-antitrypsin by an immunoperoxidase technique, indicating the diagnosis of malignant fibrous histiocytoma (MFH). Electron microscopic findings were also consistent with MFH. We believe that this is the first well-documented case of MFH arising from the stomach and small intestine, to the best of our knowledge.  相似文献   
69.
A new characterization of depth-ionization parameters for electron beams is empirically deduced from our data analysis based on the divided difference method (the DD method), which employs the numerical differential of an ionization curve. The important feature of the present method is that it does not necessarily require normalized percent depth-ionization (NPDI) data. The depth of 50% of maximum ionization, I50, which is an important parameter for electron beam dosimetry, can be deduced from the analysis of an unnormalized (or partial) depth-ionization (UDI) curve obtained over a short interval of depth. The values of I50 determined by the DD method are in agreement to within 0.1 mm for energies of 4, 6, and 9 MeV, compared with the ones determined by the TG-51 protocol method (or the conventional method), and the difference was 0.9 mm for 12 and 15 MeV. The dose at the reference depth, dref, calculated from I50 by the DD method, is found to be in agreement with TG-51 to within 0.1%. The field size dependence of the DD method using UDI data was studied for three field sizes: 6 x 6, 10 x 10, and 20 x 20 cm2. For all energies, the discrepancies of I50 as determined by both methods were 0.9 mm on average for the 6 x 6 cm2 fields and 0.6 mm for the other two field sizes. This dependence was remarkable for 6 x 6 cm2 fields for 12 and 15 MeV, and the discrepancies shown by the DD method were 1.2 mm for 12 MeV and 1.8 mm for 15 MeV, respectively. Since the reference field size in clinical dosimetry is usually 10 x 10 cm2, this dependence will not affect clinical dosimetry. The DD method could be an alternative option for checking beam quality in dose calibration.  相似文献   
70.
PD-1 and its ligands, B7-H1/PD-L1 and B7-DC/PD-L2, have been identified recently as CD28-B7 family molecules that are implicated in immune regulation. Lichen planus (LP) is a T cell-mediated chronic inflammatory mucocutaneous disease. We investigated the expression and function of PD-1 and its two ligands in LP. Immunohistochemical examination revealed the abundant expression of PD-1 and B7-H1 in infiltrating T cells and macrophages, and lower-level expression of B7-DC on macrophages in the subepithelium. Interestingly, substantial expression of B7-H1 on keratinocytes (KCs) was found close to the numerous T cell infiltrates in the subepithelium. Unstimulated cultured KCs expressed both B7-H1 and B7-DC, and their expression was upregulated by proinflammatory cytokines, particularly IFN-gamma. The T-cell proliferative responses and IFN-gamma production that were induced by IFN-gamma-treated KCs were augmented preferentially by anti-B7-H1 mAb, but not by anti-B7-DC mAb. These results indicate the regulatory role of B7-H1 on KCs in the interactions with T cells. Our results suggest that the induction of B7-H1 on KCs may play an important role in tolerance induction in the inflamed oral mucosa and skin.  相似文献   
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