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91.
92.
Masaki Iwai Yasutaka Ishu Yoshihiro Kitagawa Kazunobu Tada Motomu Kashiwadani Takeshi Okanoue Kei Kashima 《Medical molecular morphology》1993,26(3-4):207-210
The immunoreactivity of albumin (ALB) was observed in the hepatocytes of fetal rats on day 18 of gestation, and was especially observable in immature rough endoplasmic reticulum (rER) and Golgi apparatus (GA); by then, a small amount of silver grains of ALB mRNA could already be detected. Just after birth, immunoreactivity of ALB could be observed in fine granules or diffusely in all hepatocytes, and was present in rER and GA. One week after birth immunoreactivity of ALB was observed in all hepatocytes and was visible in developed rER and GA; the grains of ALB mRNA were present in all hepatocytes. 相似文献
93.
Prevention of autoimmune symptoms in autoimmune-prone mice by elimination of B-1 cells 总被引:4,自引:1,他引:4
Murakami Masao; Yoshioka Hideyuki; Shirai Toshikazu; Tsubata Takeshi; Honjo Tasuku 《International immunology》1995,7(5):877-882
Our recent studies on an autoantibody-transgenic mouse linedemonstrated that peritoneal B-1 cells are responsible for autoimmunesymptoms. However, whether B-1 cells in the peritoneum are generallyinvolved in the pathogenesis of autoimmune disease remains controversial.To test the possible involvement of peritoneal B-1 cells inautoimmune symptoms of autoimmune-prone NZB mice, we eliminatedthe peritoneal cells by hypotonic shock with repeated I.p. injectionof distilled water every 7 days into neonatal or 8-week-oldNZB mice. By this treatment, B-1 cells, which self- renew withinthe peritoneal cavity, are expected to be preferentially eliminated,while other peritoneal cells can be easily supplied from bonemarrows after this treatment indeed, in distilled water-treatedold NZB mice, the number of B-1 cells decreased in spleen aswell as in lamina propria of the gut but the numbers of conventionalB cells and T cells did not change. Moreover, the productionof autoantibodies against erythrocytes significantly decreasedand the occurrence of autoimmune hemolytic anemia was reducedin 12-month-old treated NZB mice. Similarly, the eliminationof peritoneal cells of NZB/NZW (NZB/W) F1; mice by water injectiondecreased anti-DNA IgG antibodies in the sera and reduced thepathological changes of the kidney. These results suggest thatperitoneal B-1 cells may be a source of autoantibody-producingcells in autoimmune diseases of NZB and NZB/W F1; mice. 相似文献
94.
Takagi A Matsuzaki T Sato M Nomoto K Morotomi M Yokokura T 《Medical microbiology and immunology》1999,188(3):111-116
The present study was designed to determine whether tumor induction by 3-methylcholanthrene (MC), a carcinogenic hydrocarbon,
can be inhibited by oral administration of Lactobacillus casei strain Shirota (LC). C3H/HeN mice were divided into four groups and assigned to the following treatments: treated with MC
and given control or LC-containing diet; treated with vehicle only and given control or LC-containing diet. MC (1 mg) was
injected intradermally at 7 weeks of age and the tumor incidence was monitored; LC was mixed into a diet at a concentration
of 0.05% (w/w) and the diet was fed from the day of MC injection throughout the study. Spleen cells were analyzed for the
immune parameters at 12 and 16 weeks after the MC injection. Oral feeding of mice with LC reduced tumor incidence (P < 0.05). MC treatment lowered the in vitro response to concanavalin A (Con A) of spleen cells, the secretion of interleukin-2
in spleen cell culture after stimulation of the cells with Con A and the proportions of CD3+, CD4+ and CD8+ splenic cells. However, the analysis of the spleen cells obtained from the mice treated with MC and given the LC-containing
diet revealed that these disrupted host immune parameters were maintained at the level of normal controls. These results suggest
that oral feeding of mice with LC inhibits MC-induced tumorigenesis by modulating the disrupted host immune responses during
MC carcinogenesis.
Received: 14 April 1999 相似文献
95.
Production of Macrophage Migration Inhibition Factors by Virus-Infected Cell Cultures 总被引:3,自引:3,他引:3 下载免费PDF全文
Macrophage migration inhibitory (MIF-like) activity was demonstrated in the supernatant fluids from cultures of African green monkey kidney cells (BGM) infected with mumps virus or Newcastle disease virus. We could detect no such activity in noninfected cultures. The virus-induced activity reported here is not due to nonspecific cytotoxic material released by dead or dying cells, and it does not require cell replication for its production. Preliminary estimates of molecular weight by Sephadex G-100 chromatography revealed a broad band of activity associated with the 45,000 and 65,000 markers. These are significantly smaller than previously reported chemotactic substances from virus-infected cultures, and thus appear to represent different cell products. These MIF-like factors may be produced concomitantly with interferon. However, ultraviolet irradiation of appropriate duration abolishes the ability of viruses to induce substances with MIF-like activity while preserving the ability to induce interferon. This strongly suggests that interferon is not the agent responsible for the macrophage migration inhibition effect. The functional properties of these various cell products induced by virus infection suggest that they all may play a role in the response to virus infection in vivo. 相似文献
96.
Nuclear accumulation of beta-catenin in intestinal-type gastric carcinoma: correlation with early tumor invasion 总被引:4,自引:0,他引:4
Miyazawa K Iwaya K Kuroda M Harada M Serizawa H Koyanagi Y Sato Y Mizokami Y Matsuoka T Mukai K 《Virchows Archiv : an international journal of pathology》2000,437(5):508-513
Mutation of the adenomatous polyposis coli gene, which is known to be an early event in the carcinogenesis of intestinal-type gastric carcinoma, leads to accumulation of beta-catenin. In addition, beta-catenin has been found to activate down stream signaling molecules in the wingless/Wnt pathway. In this study, the clinical significance of nuclear accumulation of beta-catenin was evaluated in gastric carcinoma. Immunohistochemical staining showed nuclear localization in 16 (12%) of 139 (94 intestinal-type and 45 diffuse-type) gastric carcinomas, and all 16 lesions with nuclear staining were intestinal-type adenocarcinomas. Of the 16 cases, 15 were in the early clinical stage. In the remaining case, the lesion had invaded the subserosal layer and showed strong nuclear staining at the invasive front. In 14 of the 16 cases with nuclear localization, there were no abnormal mobility shifts detected using polymerase chain reaction-single strand conformational polymorphism analysis. This was confirmed using direct sequencing analysis, which revealed the wild-type sequence in the 12 cases tested. Nuclear accumulation of beta-catenin did not correlate with lymph node metastasis or 5-year survival. These findings suggest that high intranuclear levels of beta-catenin protein play an important role in early tumor growth and may function in initiation of invasive processes in intestinal-type gastric carcinoma. 相似文献
97.
Takeshi Tana Nobuhiro Kamikawaji Christopher J. Savoie Tohru Sudo Yurika Kinoshita T. Sasazuki 《Journal of human genetics》1998,43(1):14-21
Susceptibility to a series of autoimmune diseases is strongly associated with particular HLA class II alleles. Identification
of T cell clones and antigenic epitopes bound by HLA class II molecules involved in autoimmune diseases is critical to understanding
the etiology of these HLA class II-associated diseases. However, establishment of T cell clones in autoimmune diseases is
difficult because the antigenic peptides are unknown. Peptide library methods which include all possible peptide sequences
offer a potentially powerful tool for the detection of cross-reactive antigenic peptides recognized by T cells. Here, we reduced
the number of peptides per mixture by utilizing the known binding motifs of peptides for the HLA-DRB1*0405 molecule and evaluated
the effectiveness of this library design. Each library mixture evoked a strong proliferative response in the unprimed peripheral
blood lymphocytes (PBL) from HLA-DRB1*0405-positive donors but little or no response in the PBL from HLA-DRB1*0405-negative donors. The library also detected antigenic peptides that activated three antigen-specific T cell lines restricted
by HLA-DRB1*0405, with different specificities. The motif-based approach thus presents a powerful method for monitoring T
cells in large, heterogeneous T cell populations and is useful for the identification of the mimic peptide epitopes of T cell
lines and clones.
Received: October 3, 1997 / Accepted: October 23, 1997 相似文献
98.
This report describes a 67-year-old male with inoperable gastric cancer accompanied by marked tissue and peripheral eosinophilia without evidence of allergic disorders or parasitic infestation. Autopsy revealed an advanced gastric cancer of scirrhous type with metastases to pancreas, bone marrow, ileum, lungs, and lymph nodes. Excessive numbers of mature eosinophils were present in univolved bone marrow, liver and spleen as well as among the signet ring cell component of the cancer in either primary or metastatic sites. The primary cancer also possessed a component of tubular adenocarcinoma which was associated with only a few eosinophils. Hence, we speculate that an eosinophil mobilizing (chemotactic and/or proliferating) factor (s) was produced by the signet ring cancer cells. 相似文献
99.
Yoshikazu Yoshida Toshimi Miyazaki Minoru Hirano Takemoto Shin Tadahide Totoki Takeshi Kanaseki 《Neuroscience letters》1981,22(2):91-95
Following horseradish peroxidase (HRP) injection into the cephalopharyngeal muscle (CeP), the hyopharyngeal muscle (HP), the thyropharyngeal muscle (TP), the cricopharyngeal muscle (CP) and the cervical esophagus muscle (CE) of the cat, labeled neurons were identified in the nucleus retrofacialis and the rostral part of the nucleus ambiguus ipsilaterally. The rostral end of the labeled cell column was located more rostrally for CeP and HP than for TP, CP and CE. No difference was noted within the former two or within the latter three. The level of the caudal end of the labeled cell column became more caudal in the order of CeP, HP, TP and CP. The caudal end was located more rostral for CE than for TP. The neurons for CE were located more ventro-laterally than those for the other muscles. 相似文献
100.
Mei N Tamae K Kunugita N Hirano T Kasai H 《Environmental and molecular mutagenesis》2003,41(5):332-338
In order to improve 8-hydroxyguanine (8-OH-Gua) detection in DNA, we digested isolated DNA with nuclease P1 and analyzed for 8-hydroxydeoxyguanosine 5'-monophosphate (8-OH-dGMP) using a high-performance liquid chromatography system equipped with an electrochemical detector (HPLC-ECD). The amount of 8-OH-Gua in the DNA was expressed as the ratio of 8-OH-dGMP to deoxycytidine monophosphate (dCMP). Using this analysis, the background level of 8-OH-Gua in DNA from human lung carcinoma cells (A549) was several-fold lower than that obtained by a previous method. A549 cells were exposed to 20-60 Gy of gamma-radiation and an increase in 8-OH-Gua concentration was observed with increasing gamma-ray dose (0.3 residues per 10(7) dCMP per Gy). Moreover, by an immunohistochemical procedure using a commercial FITC-kit, 8-OH-Gua was clearly detected in A549 cells and the fluorescence intensity of cells with oxidative DNA damage increased with the doses of gamma-irradiation. Using an endonuclease nicking assay, we also found that gamma-rays decreased 8-OH-Gua repair activity. The results indicate that 8-OH-dGMP is a useful and sensitive marker for estimating oxidative damage in DNA. 相似文献