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1.
Masanori Shinzato Mikihiro Shamoto Satoru Hosokawa Chiyuki Kaneko Akido Osada Miyuki Shimizu Asako Yoshida 《Biotechnic & histochemistry》1995,70(3):114-118
The present study shows that Langerhans cells can be differentiated from Interdigitating cells at the light microscopic level. Superficial lymph nodes and skin taken from necropsies and the lymph nodes of dermatopathic lymphadenopathy (DPL) were used for this experiment. Sections of lymph node and skin were embedded using the acetone, methyl benzoate and xylene (AMeX) method and dendritic cells were immunostained with anti S-100 protein antibody (S-100, and OKT-6 (CD1a) using the restaining method. Langerhans cells in the skin were positive for both CD1a and S-100. Dendritic cells positive for both CD1a and S-100, and dendritic cells positive for S-100, but not for CD1a were observed in superficial lymph nodes. In normal superficial lymph nodes, there were more interdigitating cells than Langerhans cells. The majority of the dendritic cells in the DPL were Langerhans cells. We conclude that the S-100 and CD1a positive cells are Langerhans cells, and the S-100 positive-CD1a negative cells are interdigitating cells. 相似文献
2.
Shun-Ichiro Kawabata Takashi Morita Toshiyuki Miyata Shigenori Kaida Sadaaki Iwanaga Hideo Igarashi 《Journal of Protein Chemistry》1987,6(1):17-32
The bacterial protein staphylocoagulase binds stoichiometrically to human prothrombin, resulting in a coagulant complex, staphylothrombin. The enzymatic properties of staphylothrombin differ from those of -thrombin in their substrate specificities toward natural and synthetic substrates, in addition to their interaction with protease inhibitors. In order to obtain information about the region of staphylocoagulase that interacts with human prothrombin, staphylocoagulase was cleaved by -chymotrypsin. Limited -chymotryptic cleavage of staphylocoagulase yielded three large fragments, of 43, 30, and 20 kD. The 43-kD fragment exhibited a high affinity for human prothrombin (Kd=1.7 nM), which is comparable to the affinity observed using intact staphylocoagulase (Kd=0.46 nM). A complex of the 43-kD fragment and prothrombin possessed both clotting and amidase activity essentially identical to that observed in a complex of intact staphylocoagulase and prothrombin. The 30-kD fragment exhibited weaker affinity for prothrombin (Kd=120 nM.) While clotting activity was not observed with a complex of this fragment and prothrombin, it nonetheless possessed a weak amidase activity. The 20-kD fragment was found only to bind to prothrombin. The NH2-terminal sequence analyses of these fragments revealed that the 43-kD fragment constitutes the NH2-terminal portion of staphylocoagulase, and contains the 30-kD and 20-kD fragments. It is therefore concluded that the functional region of staphylocoagulase for binding and activation of prothrombin is localized in the NH2-terminal region of the intact protein. The 43-kD fragment contained 324 amino acids with a molecular weight of 38,098. The 43-kD fragment had an unusual amino acid composition based on a sequence in which the sum of Asp (28 residues), Asn (22), Glu (35), Gln (9), and Lys (52) residues accounted for more than 45% of the total. A comparison of the amino acid sequence of the 43-kD fragment with that of streptokinase did not reveal any obvious sequence homology. There was also no sequence homology with that of trypsin, -chymotrypsin, and elastase.This article was presented during the proceedings of the International Conference on Macromolecular Structure and Function, held at the National Defence Medical College, Tokorozawa, Japan, December 1985. 相似文献
3.
Junichi Ishihara Nagahiro Saijo Yasutsuna Sasaki Hidehiko Nakano Akira Ozaki Hidenobu Takahashi Masanori Sakurai Kazuhiko Nakagawa Masaaki Iigo Fumihiko Kanzawa Akio Hoshi Weon Seon Hong James R. Jett Terumi Takahashi 《Cancer immunology, immunotherapy : CII》1987,24(3):185-189
Summary The antitumor effect of recombinant human tumor necrosis factor (rH-TNF) on two clones of rat fibrosarcoma with different metastatic potential to lymph nodes was examined. The colony formation of clone A, which has high metastatic potential, was completely inhibited by continuous exposure to rH-TNF at 50 U/ml. In contrast, colony formation of clone G, which has low metastatic potential, was not inhibited by high concentrations of rH-TNF (10,000 U/ml). The inhibitory effect of rH-TNF on colony formation by clone A was also observed with a 1-h exposure to rH-TNF. This effect was time and concentration dependent, as determined by the colony assay, 3H-thymidine uptake assay, and 51Cr-release assay. 3H-thymidine and 3H-uridine uptake per cell of clone A exposed to rH-TNF was not decreased. This suggests that the mechanisms of the antitumor effect of rH-TNF were not due to inhibition of DNA and RNA synthesis of tumor cells. In vivo growth and lymph node metastases of clone A inoculated i.p. to Donryu strain rats were completely suppressed by 14 consecutive i.p. injections of 105 or 106 U/kg per day of rH-TNF. On the other hand the growth of clone G was not influenced by rH-TNF administration. 相似文献
4.
Seasonal and ontogenetic changes in natural development timewere studied for Eodiaptomus japonicus in Lake Biwa in 1986and 1987. Wild individuals in a certain developmental stagewere collected, fed on natural food and examined until theyhad moulted twice. Natural development times fluctuated irrespectiveof temperature from May to October. Food deficiency delayeddevelopment in all feeding stages, and food availability probablydetermined natural development time. Serious food limitationraised mortality in copepodid stage I. In November developmentwas delayed even with enough food. The development of E.japonicuswas almost isochronal except for a short prefeeding naupliarstage I and a long copepodid stage V. 相似文献
5.
Isolation and Characterization of an Enterobacter cloacae Strain That Reduces Hexavalent Chromium under Anaerobic Conditions 总被引:12,自引:6,他引:6
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Pi-Chao Wang Tsukasa Mori Kohya Komori Masanori Sasatsu Kiyoshi Toda Hisao Ohtake 《Applied microbiology》1989,55(7):1665-1669
An Enterobacter cloacae strain (HO1) capable of reducing hexavalent chromium (chromate) was isolated from activated sludge. This bacterium was resistant to chromate under both aerobic and anaerobic conditions. Only the anaerobic culture of the E. cloacae isolate showed chromate reduction. In the anaerobic culture, yellow turned white with chromate and the turbidity increased as the reduction proceeded, suggesting that insoluble chromium hydroxide was formed. E. cloacae is likely to utilize toxic chromate as an electron acceptor anaerobically because (i) the anaerobic growth of E. cloacae HO1 accompanied the decrease of toxic chromate in culture medium, (ii) the chromate-reducing activity was rapidly inhibited by oxygen, and (iii) the reduction occurred more rapidly in glycerol- or acetate-grown cells than in glucose-grown cells. The chromate reduction in E. cloacae HO1 was observed at pH 6.0 to 8.5 (optimum pH, 7.0) and at 10 to 40°C (optimum, 30°C). 相似文献
6.
To elucidate the protective effects of glutathione against iron-induced peroxidative injury, changes in the hepatic glutathione metabolism were studied in chronically iron-loaded mice. When the diets of the mice were supplemented with carbonyl iron, iron deposition occurred primarily in the parenchymal cells of the liver. In addition, expiratory ethane production was elevated, suggesting an enhancement in lipid peroxidation. In iron-loaded mice, the total hepatic glutathione contents were higher (6.21 +/- 0.53 mumol/g wet wt.) than in control mice (4.61 +/- 0.31 mumol/g wet wt.), primarily due to an increase in the reduced glutathione contents. The value of oxidized glutathione was also higher (98.5 +/- 8.1 nmol/g wet wt.) than in the controls (60.8 +/- 9.5 nmol/g wet wt.), and the ratio of oxidized glutathione to total glutathione increased. The excretion rate of glutathione from the hepatocytes in iron-loaded mice also increased. These observations suggest that chronic iron-loading of mice stimulates lipid peroxidation and oxidation of glutathione and that peroxidized molecules may be catabolized using reduced glutathione. 相似文献
7.
Masanori Ito Kazuhiro Yoshida Eikai Kyo Ayse Ayhan Hirofumi Nakayama Wataru Yasui Hisao Ito Eiichi Tahara 《Virchows Archiv. B, Cell pathology including molecular pathology》1990,59(1):173-178
We have examined the expression of mRNAs for epidermal growth factor (EGF), transforming growth factor-alpha (TGF-α), EGF
receptor (EGFR), PDGF-A chain (PDGFA), PDGF-B chain (PDGFB) and PDGF receptor (PDGFR) genes in seven human colorectal carcinoma
cell lines and 18 human colorectal carcinomas.
In surgically resected specimens of the 18 colorectal tumors, TGF-α, EGFR, PDGFA, PDGFB and PDGFR mRNAs were detected at various
levels in 15 (83%), 9 (50%), 18 (100%), 8 (44%) and 12 (67%), respectively. They were also detected in normal tissues. Interestingly,
EGF mRNA was detected in only five (28%) of the tumors, but not in normal mucosa. Expression of EGF was also confirmed immunohistochemically
in tumor cells. Of the five tumors expressing EGF, four expressed EGFR mRNA and showed a tendency to invade veins and lymphatics.
All the colorectal carcinoma cell lines expressed TGF-α mRNA, and five cell lines expressed EGFR mRNA simultaneously. Production
of TGF-α protein by DLD-1 and CoLo320DM cells was confirmed by TGF-α specific monoclonal antibody binding assay. The spontaneous3H-thymidine uptake by DLD-1 was suppressed by an anti-TGF-α monoclonal antibody. PDGFA and PDGFB mRNA were also expressed
in four cell lines, but PDGFR and EGF mRNA was not detected. These results suggest that human colorectal carcinomas express
multi-loops of growth factors and that TGF-α produced by tumor cells functions as an autocrine growth factor in human colonic
carcinoma. 相似文献
8.
Dr. Kazuo Tamura Masanori Takeuchi Nobuyuki Hirakawa Kiyokazu Toyoda Masaru Minoda 《Biotherapy》1990,2(3):223-226
The 35-year-old man with myelodysplastic syndrome (MDS) and granulocytopenia with dry cough and high fever was eventually found to have a left perinephric abscess ofStaphylococcus aureus. He underwent left nephrectomy and drainage of perinephric space in conjunction with appropriate antibiotics. However, because of persistent granulocytopenia,Staph. aureus never cleared up with formation of only poor granulation. Recombinant human granulocyte colony-stimulating factor (G-CSF) was added to the above treatment leading to prompt improvement in granulocytopenia and emergence of the good granulation tissue. G-CSF will probably become one of the important agents in treating MDS with granulocytopenia. 相似文献
9.
10.
Nichola J. K. Hole Edmundo Lamoyi Masanori Komatsu Nagaradona Harindranath Glendowlyn O. Young-Cooper Rose G. Mage 《Immunogenetics》1988,28(2):99-107
In order to investigate linkage, we used serum allotypes of the two rabbit C
isotypes and restriction fragment length polymorphisms (RFLPs) of the genes for V
, C
, and T-cell receptor C
. The inheritance of these genetic markers was studied through backcross and F2 matings. Southern analysis and hybridization of genomic DNA with a C probe detected a 5 kb Pst I fragment linked to expression of the K2bas1 allotype and the presence of the 1b
bas gene and a 6.6 kb Pst I fragment linked to the expression of the K1b9 allotype, the presence of the 2
bas2 gene and lack of expression of the K2bas1 allotype. A V probe detected a 1.3 kb Eco RI fragment linked to the presence of the 1b
bas gene and expression of the K2bas1 allotype. In contrast, the 9 or 14 kb Eco RI RFLP (C
a or C
b) detected with a Tcr
chain probe segregated independently from C allotypes and RFLPs. It has previously been found that C and C
are also unlinked in man, whereas in the mouse they are linked at a distance of 8 centimorgans. 相似文献