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81.
Fu J Hato M Ohmae H Matsuoka H Kawabata M Tanabe K Miyamoto Y Leafasia JL Chinzei Y Ohta N 《Parasitology research》2000,86(5):345-351
We analyzed the relationships between levels of antibody specific for merozoite surface glycoprotein-1 (MSP1) of Plasmodium falciparum and clinical manifestations in humans. We prepared recombinant MSP1 proteins representing block 3 (M3), block 6 (M6), blocks
1–6 (M1/6), and block 17. When we divided the slide-positive individuals in Guadalcanal into symptomatic and asymptomatic
groups, the former group showed lower IgG levels against M6 and block 17, but not against M3, than did the asymptomatic group
(P < 0.01). The possibility of nonspecific suppression was unlikely, given that the levels of antibody against poliomyelitis
virus observed in the two groups were almost the same. Among the IgG subclasses tested, production of cytophilic IgG3 seemed to be dominant. When we analyzed epitopes recognized by antibodies against block 17, a peptide (SSSNFLGIS) was preferentially
recognized by sera from asymptomatic individuals. These results suggest that clinical symptoms occurring during falciparum
malaria seem to be associated with the development of levels of antibody against particular epitopes on MSP1, which is under
the control of an immunoregulatory mechanism.
Received: 1 October 1999 / Accepted: 21 October 1999 相似文献
82.
Terada T Matsunaga Y Maeta H Endo K Horie S Ohta T 《Virchows Archiv : an international journal of pathology》1999,435(6):606-611
We report an autopsy case of mixed ductal-endocrine carcinoma of the pancreas presenting as gastrinoma with Zollinger-Ellison
syndrome. A 38-year-old Japanese male was found to have Zollinger-Ellison syndrome and pancreatic gastrinoma, and gastrectomy
and resection of the pancreatic tumor were performed. However, hypergastrinemia persisted, and the patient died of disseminated
carcinomatosis at 62 years of age, 24 years after the onset of Zollinger-Ellison syndrome. At autopsy, the main tumor was
present in the residual pancreas, and metastases were noted in many organs. In the pancreas and other organs, ductal and endocrine
carcinoma areas were mixed and there was a gradual transition between the two. No acinar differentiation was noted. The ductal
elements were positive for mucins and carcinoembryonic antigen but negative for neuroendocrine markers, while endocrine elements
were positive for chromogranin A and synaptophysin and to a lesser extent for gastrin, but negative for mucins and carcinoembryonic
antigen. The ductal elements comprised about 30% of the tumor cells, and endocrine elements 70%. According to the revised
World Health Organization classification, our case was diagnosed as mixed ductal-endocrine carcinoma. Our case is rare because
the tumor manifested as gastrinoma with Zollinger-Ellison syndrome and the patient survived for 24 years. To the best of our
knowledge, no such case has been reported. Our case suggests that pancreatic endocrine tumors may evolve into mixed ductal-endocrine
carcinomas.
Received: 14 April 1999 / Accepted: 7 July 1999 相似文献
83.
Kazuhiro Tsukamoto Nobutaka Ohta Yasumasa Shirai M. Emi 《Journal of human genetics》1998,43(4):278-279
Tumor necrosis factor alpha (TNFα) in activated monocytes exerts cytotoxic activity and has a variety of other biological
effects. We isolated a polymorphic dinucleotide (CA) repeat sequence from a genomic clone containing the gene located at 6p21.3.
High heterozygosity (0.80) makes this polymorphism a useful marker in the genetic study of disorders affecting immunological
response and cell differentiation.
Received: June 2, 1998 / Accepted: June 24, 1998 相似文献
84.
Haruyo Nakajima PhDa Satoshi Hachimuraa Shinya Nishiwakia Toshiyuki Katsuki MD PhDb Naoki Shimojo MD PhDb Akio Ametani PhDa Yoichi Kohno MD PhDb Shuichi Kaminogawa PhDa 《The Journal of allergy and clinical immunology》1996,97(6):1342-1349
To study cow’s milk allergy at the cellular level, we assessed the reactivity of peripheral blood mononuclear cells from patients allergic to cow’s milk to αs1-casein, which is one of the major allergens in cow’s milk. Proliferation of the cells to αs1-casein activation showed a rather weak response. Therefore to understand T-cell reactivity to αs1-casein in more detail, we prepared αs1-casein–specific T-cell lines from patients allergic to cow’s milk and established 26 T-cell lines. These T-cell lines could be classified into three groups by analyzing their surface marker expression: those containing predominantly CD4+CD8- T cells, those containing both CD4+CD8- and CD4-CD8+ T cells, and those containing predominantly CD4-CD8+ T cells. The CD8+ T cells were obtained at an unexpectedly higher frequency from the patients. These T-cell lines produced interferon-γ and IL-4. These results suggest that CD8+ T cells specific for αs1-casein and CD4+ T cells were primed by the stimulation with αs1-casein in patients allergic to milk and that both T cells may play a key role in the onset, progression of, or recovery from cow’s milk allergy. (J ALLERGY CLIN IMMUNOL 1996;97:1342-9.) 相似文献
85.
Minora Ogata Hidekazu Shigematsu Akio Sakai Yasunori Yanagidaira Gou Ueda Toshio Kobayashi 《Pathology international》1988,38(5):549-558
We carried out an experiment to analyze morphological differences in hearts of rats well adapted and poorly adapted to chronic hypoxia. Male and female Wistar rats, 1 week, 4 weeks and 9 weeks old, were employed on the assumption that adaptive ability was dependent on age and sex. These rats were raised at an altitude of 2,400 m and were kept for 7 to 9 weeks. Control groups were maintained at an altitude of 600 m during the same period of time. Each group consisted of 4 to 6 rats. At the end of the experiment, body weight, heart weight, ratio of heart weight to body weight and hematocrit were measured, and ventricular wall thickness, myocardial fiber diameter, capillary supply and mitochondria were morphometrically studied. Of the 6 experimental groups, the 4-week-old male rats (M2) had the highest body weight, as compared with the other experimental groups. In addition, relative to these other experimental groups, the following features were found for M2. Heart weight was intermediate, heart weight/body weight ratio was low and hematocrit was also low. Ventricular wall thickness was intermediate in the right ventricle (RV) and interventricular septum (IVS) but was thin in the left ventricle (LV). Myocardial fiber diameter was intermediate in the RV, large in the IVS and small in the LV. Capillary supply was intermediate in the RV and dense in the IVS and LV. Mitochondria were small but cristal density and percentage area, estimated from electron micrographs, were found to be high. These data showed that in well developed rats under chronic hypoxia, there is good development of capillary supply with corresponding restriction of cardiac hypertrophy, while hematocrit count and mitochondria are also affected. 相似文献
86.
A 56-year-old Japanese man with a malignant lymphoma of the parotid gland was reported. The tumor was located in the superficial lobe of the parotid gland, and somewhat invaded the surrounding soft tissues, but the regional lymph nodes were not involved. Histologically, the tumor was composed of round cells with plasmacytoid configurations and small lymphocytes. The plasmacytoid cells showed eccentric nuclei with fairly marked irregularities and perinuclear halos. In a large number of tumor cells, a monoclonal cytoplasmic immunoglobulin (CIg), IgG-Kappa type, was demonstrated by the PAP method. Ultrastructurally, some of the tumor cells showed welldeveloped endoplasmic reticulum. From these findings, this tumor was diagnosed as a diffuse B-cell lymphoma, mainly composed of lymphoplasmacytoid cells. And this tumor may bear a similar nature to an extramedullary plasmacytoma of the classical terminology. Malignant lymphoma of the parotid gland is rare but a case with the demonstration of monoclonal CIg is considered very rare. ACT A PATHOL. JPN. 34: 1459–1467, 1984. 相似文献
87.
Joji Haratake Atsuo Jimi Akio Horie Taizoh Inokuma Masato Ohno 《Pathology international》1984,34(4):925-933
This is a case report of a malignant mesenchymoma of the esophagus in a 50?year-old Japanese man. The tumor was a sessile polypoid mass showing a downward invasion limited to the submucosa of the esophagus. Histologically, the lesion contained rhabdomyosarcomatous and osteosarcomatous areas, in addition to an ill-defined fibrosarcomatous element. In contrast with reports of carcinosarcoma up to the present, this tumor lacked any invasive lesion of an epithelial malignancy. The morphogenesis of these tumor groups was discussed from a hamartoblastomatous standpoint. Acta pathol. jpn. 34: 925~933, 1984. 相似文献
88.
Y Ohta K Shimamura N Lertprasertsuke M Horiuchi R Y Osamura 《Acta pathologica japonica》1989,39(7):446-450
An autopsy case of malignant midline reticulosis (MMR) is reported. The patient, a 42-year-old Japanese male, died after a clinical course of 22 months. Autopsy revealed extensive infiltration of generalized organs by the tumor cells, suggesting that the disease was highly malignant in nature. Staining with monoclonal antibodies against T-cell surface antigens Leu 4 on frozen sections and UCHL1 on paraffin-embedded sections enabled us to examine the phenotype of the tumor cells with good morphological preservation and to verify the T cell nature of the tumor. 相似文献
89.
90.
Tadao Tanimoto Shigeto Yamamoto Madoka Taniai Mutsuko Taniguchi Harumi Ariyasu Chie Ushio Miho Aga Yohei Mukai Yasuo Tsutsumi Toshio Ariyasu Tsunetaka Ohta Shigeharu Fukuda 《Journal of interferon & cytokine research》2007,27(6):517-523
Although there are at least 13 interferon-alpha (IFN-alpha) subtypes in humans, interactions between the subtypes remain unknown. To understand IFN-alpha interactions, we examined the antiproliferative activities and the receptor binding affinities of different combinations of IFN-alpha2 and IFN-alpha8 using six renal cell carcinoma (RCC) cell lines. Although IFN-alpha8 was the more potent subtype, synergistic and antagonistic antiproliferative effects were also observed in certain combinations of IFN-alpha2 and IFN-alpha8. To analyze the interactions between IFN-alpha2 and IFN-alpha8, the receptor-binding kinetics of different combinations of IFN-alpha2 and IFN- alpha8 to the IFN-alpha receptors, IFNAR-1 or IFNAR-2, were measured using a surface plasmon resonance-based biosensor. Unexpectedly, the receptor binding kinetics to IFNAR-2 but not to IFNAR-1 were mutually related to antiproliferative activity and increase in the binding speed (K(a)) for IFNAR-2. Moreover, we observed the increased fluorescence intensity (FI) of biotin-labeled IFN-alpha8 to IFNAR-2 by receptor binding inhibition assay with unlabeled IFN-alpha2 but not the other combinations. These findings indicate that the binding manner of IFN-alpha8 for IFNAR-2 is different from that of IFN-alpha2, suggesting that binding of IFN-alpha8 rather than binding of IFN-alpha2 to IFNAR-2 leads to activation and subsequent antiproliferative activity despite the same antiviral activity in RCC. 相似文献