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111.
Detection of tumour necrosis factor/cachectin in pleural effusion of patients with lung cancer. 总被引:1,自引:0,他引:1
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Y Ishii Y Uchiyama S Hasegawa T Kinoshita K Mitsui H Kojima T Fujita 《Clinical and experimental immunology》1990,80(3):350-353
We have found that the pleural effusion obtained from a patient with lung cancer (adenocarcinoma) has cytotoxic activity against the patient's lung cancer cells. This finding occurred in the course of establishing a lung cancer cell line from the patient's pleural effusion. The cytotoxic factor was partially purified from the pleural effusion and characterized. It had cytotoxicity against L-929 mouse fibroblasts in the standard 18-h killing assay of tumour necrosis factor (TNF). By molecular sieving chromatography, the activity appeared at molecular weight of 50,000. This activity was completely blocked by a monoclonal antibody to TNF. From these results, we conclude that the cytotoxic factor in the pleural effusion is TNF. The concentration of TNF in the pleural effusion was 34.5 pg/ml by radioimmunoassay. In addition, we detected TNF activity and protein in two other cases of carcinomatous pleural effusion. Therefore, it would appear that in vivo TNF displays cytotoxic activity against cancer cells. 相似文献
112.
Takahiko Hara Masatake Yamauchi Ei-ichi Takahashi Masato Hoshino Kazuhisa Aoki Dai Ayusawa Masao Kawakita 《Somatic Cell and Molecular Genetics》1993,19(6):571-575
We have cloned a segment of the human gene encoding UDP-galactose translocator by genetic complementation of its defective mutant in mouse FM3A cells. Chromosome mapping using fluorescentin situ hybridization revealed that the cloned gene hybridized to the Xp11.23-11.23 region of the X chromosome. This region is shared by the locus of Wiskott-Aldrich syndrome, an X-linked recessive immunodeficiency disorder, characterized by defective sugar chains on cell surface components. Genetic and phenotypic similarities suggest a possible link between UDP-galactose translocator and the Wiskott-Aldrich syndrome (WAS). 相似文献
113.
A Masunaga T Oka H Nakamura K Kinoshita T Yamashita I Sugawara S Itoyama 《Acta pathologica japonica》1992,42(12):916-922
A case of intrauterine tumor in a 62-year-old Japanese woman is presented. It was thought initially that this was a case of uterine tumor resembling an ovarian sex cord tumor. To examine the cytological features of the tumor cells, electron microscopical and immunohistochemical studies were done, and a hormone assay of the tumor tissue was performed. The tumor cells were rich in rough endoplasmic reticulum (rER), mitochondria and microfilaments. Some tumor cells tended to form glandular patterns, but these epithelial elements were frequently scattered among fibrous stromal elements. Though many tumor cells with an epithelial appearance possessed a large quantity of cytokeratin and vimentin, they did not secrete estradiol, progesterone, testosterone or human chorionic gonadotropin. This case was finally diagnosed as an intramural uterine stromal tumor with epithelial differentiation after taking all the available data into consideration. This would be classified as an endometrial stromal tumor with epithelial elements, recently proposed and named by Clement and Scully. 相似文献
114.
Masahiko Kuroda Hajime Horiuchi Teruaki Oka Tsuyoshi Ishida Akira Ono Masao Kawakita Rikuo Machinami 《Virchows Archiv : an international journal of pathology》1993,423(3):209-213
Ninety-one cases of human bone and soft tissue tumours were studied for calcium pump expression by strepto-avidin-biotin immunohistochemical staining with a monoclonal antibody against sarcoplasmic reticulum calcium-ATPase (mAb6F5). Two out of 5 cases of embryonal rhabdomyosarcoma, 1 out of 5 cases of biphasic synovial sarcoma, 4 of 4 cases of chordoma and all of 3 chondrosarcoma cases were positive for mAb6F5. Although this novel monoclonal antibody can be used as a marker of myogenic tumours, the present positive result for endoplasmic reticulum calcium-ATPase (calcium pump) in other tumours including chordoma, chondrosarcoma and synovial sarcoma indicates a wider immunoreactivity. The findings further suggest that intracellular calcium may play an important role in cell proliferation and/or differentiation. 相似文献
115.
Breast milk macrophages spontaneously produce granulocyte-macrophage colony-stimulating factor and differentiate into dendritic cells in the presence of exogenous interleukin-4 alone
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Ichikawa M Sugita M Takahashi M Satomi M Takeshita T Araki T Takahashi H 《Immunology》2003,108(2):189-195
Peripheral blood monocytes extravasate and differentiate into tissue macrophages to mediate effective local defence, but how tissue-specific stimuli and environments may influence their functions remains unknown. Here, we found that peripheral blood monocytes gained the ability to produce granulocyte-macrophage colony-stimulating factor (GM-CSF) upon exposure to breast milk and differentiated into CD1+ dendritic cells (DCs) in the presence of exogenous interleukin-4 (IL-4) alone. This in vitro observation appeared physiologically relevant since macrophages that were freshly isolated from breast milk were also found to produce GM-CSF spontaneously. Furthermore, in contrast to peripheral blood monocytes that differentiated into DCs only in the presence of both exogenous GM-CSF and IL-4, differentiation of breast milk macrophages into DCs was induced by incubation with exogenous IL-4 alone. These IL-4-stimulated breast milk macrophages were efficient in stimulating T cells, suggesting their potential role in mediating T-cell-dependent immune responses in situ. On the other hand, unexpected expression of DC-SIGN, a DC-specific receptor for human immunodeficiency virus (HIV), even in unstimulated breast milk macrophages, may favour HIV infection, resulting in an increased risk of mother-to-infant vertical transmission of the virus via breast milk. Thus, tissue-specific development of macrophages is often linked to effective local immunity, but may potentially provide an opportunity for a pathogen to spread and transmit. 相似文献
116.
Yoshida M Torigoe S Ikeue K Yamada M 《Clinical and diagnostic laboratory immunology》2002,9(2):388-393
Seroprevalence of human herpesvirus 6 (HHV-6) and HHV-7 infections is very high throughout the world, and almost all people are exposed first to HHV-6 and second to HHV-7 in their childhood. However, it is not clear whether the neutralizing (NT) antibody response between each virus is cross-reactive or not. To elucidate the NT antibody response between each virus, 55 serum samples from an adult group (subjects 22 to 88 years old) and 60 serum samples from a young group (subjects 2 to 18 years old) were examined by a dot blot method for detecting viral late antigen. Thirty-nine serum samples obtained from cord bloods and a few serum samples obtained from pediatric patients with exanthem subitum were also examined to assess the maternal transferred NT antibodies against each virus. The NT antibody titers against HHV-7 in the adult group remained high throughout all the individuals, and none were negative. Those against HHV-6 were high values in the young group but low values, including negative values (three samples), in the adult group. These results suggested that the NT antibody response to either HHV-6 or HHV-7 in each individual was specific to each virus and did not cross-react with each other. In the adult group, the NT antibody response to HHV-6 decreased, while that to HHV-7 remained high throughout all the individuals. Maternal transferred NT antibody titers against HHV-7 were higher and remained longer after birth than those of HHV-6, and these findings were in accord with the clinical observation that HHV-6 infection usually occurs earlier than HHV-7 infection. 相似文献
117.
In the oxidative polymerization of 2,6-dimethylphenol ( 8 ) the catalytic activities of the following semiconducting organic polymeric metal complexes were studied: polymeric complexes containing bis(ethylene-1,2-dithiolato)Cu(II) or Fe(III) complexes and copper(II) phthalocyanine structures ( 3a – c ), catalysts consisting of bis(ethylene-1,2-dithiolato)-Cu(II) or Fe(III) complex structures and hemiporphyrazine type structures ( 5a – c ), and also polymers containing a copper complex of dimercaptomaleic acid monoamide ( 7 ). It was found that a suspension of the insoluble bis(ethylene-1,2-dithiolato)Cu(II) polymeric complexes of type 3 catalyzes the polymerization in the presence of oxygen in pyridine at room temperature producing poly[oxy-(2,6-dimethyl-1,4-phenylene)] ( 9 ) in very good yields. Polymeric complexes of type 5 were inactive by themselves. However, we showed that bis(ethylene-1,2-dithiolato)Cu(II) polymeric complexes of both the 3 and 5 type possess great activities if they are used in the presence of small amounts of copper(II)-pyridine complex in pyridine solution (the chosen concentration was so low that the Cu(II)-pyridine complex alone had only a small activity). Bis(ethylene-1,2-dithiolato)Fe(III) complexes of both the 3 and 5 type were inactive even in the presence of the Cu(II)-pyridine complex. 相似文献
118.
Hayakawa T Yoshinari M Nemoto K 《Journal of biomedical materials research. Part A》2003,67(2):684-688
The aim of this study was to bind fibronectin directly to a titanium surface treated with tresyl chloride (2,2,2-trifluoroethanesulfonyl chloride) for the development of a strong connection of a dental implant to subepithelial connective tissues and/or peri-implant epithelia. Basic terminal OH groups of mirror polished titanium were allowed to react with tresyl chloride at 37 degrees C for 2 days. The tresylated titanium disk was then immersed into a fibronectin/phosphate-buffered saline solution for 24 h at 37 degrees C. The activation reaction of the basic OH of titanium with tresyl chloride was confirmed by S2p, F1s, and O1s spectra using X-ray photoelectron spectroscopy and -O-S-O2- bonds using Fourier transform infrared reflection-absorption spectroscopy. After the reaction of fibronectin with titanium, the X-ray photoelectron spectroscopy revealed the remarkable effect of the activation of terminal OH groups with the tresyl chloride treatment. The N1s peak derived from the attached fibronectin still remained after 60 s of argon-ion sputtering after tresyl chloride treatment. In contrast, the N1s peak of the specimen not treated with tresyl chloride almost disappeared after only 10 s of argon-ion etching. Fibronectin, a well-known cell-adhesive protein, could easily be attached to the titanium surface by use of the tresyl chloride activation technique. 相似文献
119.
120.
Saito A Suzuki Y Ogata S Ohtsuki C Tanihara M 《Journal of biomedical materials research. Part A》2004,70(1):115-121
Bone morphogenetic protein-2 (BMP-2) promotes the formation and regeneration of bone and cartilage, and therefore constitutes the most promising candidate for a bone repair material. However, it also has a wide range of functions, such as in organogenesis and apoptosis. Therefore, we investigated a novel synthetic peptide corresponding to residues 73-92 of BMP-2. This peptide bound to a BMP-2-specific receptor and elevated both alkaline phosphatase activity and osteocalcin mRNA in the murine cell line, C3H10T1/2. The 73-92 peptide also induced ectopic calcification when conjugated to a covalently crosslinked alginate gel. Here we report that the 73-92 peptide-conjugated alginate gel showed prolonged ectopic calcification for up to 7 weeks in rat calf muscle. In contrast, rhBMP-2-impregnated collagen gel showed maximum ectopic calcification at 3 weeks, and the calcified products that had formed disappeared after 5 weeks. Histological examination showed that the 73-92 peptide-conjugated alginate gel induced many osteoblast-like cells and few osteoclasts. In contrast, rhBMP-2-impregnated collagen gel induced many osteoclasts. These results suggest that the 73-92 peptide on alginate gel remains active at the implanted site, continuously induces differentiation of osteoblast precursor cells into osteoblasts, and activates osteoblasts to promote ectopic calcification. 相似文献