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91.
Shigenori Goto Sumitaka Sakai Jiro Kera Yukie Suma Gen-Ichiro Soma Shoshichi Takeuchi 《Cancer immunology, immunotherapy : CII》1996,42(4):255-261
Lipopolysaccharide (LPS) has been recognized as a potent antitumor agent in animal tumor models; however, its use in human
cancer therapy has been limited to only one trial, in which LPS from Salmonella was given intravenously. It was not very successful because of poor tumor response and was also toxic. We originally developed
LPS prepared from Pantoea agglomerans (LPSp), and this was a well-purified, small-molecular-mass (5 kDa) agent. We chose intradermal rather than intravenous administration
in the hope that the former would release LPS slowly into the bloodstream, and thus be less toxic while preserving antitumor
activity. In our animal tumor models, intradermal administration was indeed less toxic and more beneficial for tumor regression
than intravenous administration. We made a pilot study with intradermal administration of LPSp on the treatment of ten advanced
cancer patients. Five of them had evaluable tumor, which had failed earlier to respond to conventional chemotherapy. Cyclophosphamide
was also administered in this trial, in anticipation of its synergistic effect with LPSp. In this study LPSp was injected
intradermally into each patient twice a week, starting with an initial dose of 0.4 ng/kg, and raising it to 600 or 1800 ng/kg.
A 400-mg/m2 dose of cyclophosphamide was given intravenously every 2 weeks. After completion of the dose escalation, the treatment was
continued for at least 4 months, and it was found that 1800 ng/kg LPSp was well tolerated. A significant level of cytokines
was observed in the sera for at least 8 h. These results indicate higher tolerable doses and remarkably more continuous induction
of the cytokines than were reported in a previous study by others using intravenous administration. Three of the five evaluable
tumors showed a significant response to our combined therapy. Intradermally administered, LPS was less toxic and elicited
a tumor response in combination with cyclophosphamide; it can thus can be applied to cancer treatment even in humans.
Received: 3 August 1995 / Accepted: 2 April 1996 相似文献
92.
Ernest V. Curto Ted T. Sakai Michael J. Jablonsky Sandrine Rio-Anneheim Jean-Claude Jacquinet N. Rama Krishna 《Glycoconjugate journal》1996,13(4):599-607
We present complete1H NMR assignments for two synthetic glycopeptides representative of the carbohydrateprotein linkage region of serglycin proteoglycans. The peptides are: Ser(Galp-Xylp)-Gly-Ser-Gly-Ser(Galp-Xylp)-Gly and, Ser(Galp-Xylp)-Gly-Ser(Galp-Xylp)-Gly-Ser(Galp-Xylp)-Gly. A number of 2D NMR spectra together with a 3D NOESY-TOCSY spectrum were acquired at 600 MHz to complete the assignments of the glycopeptides dissolved in water with 40% trifluoroethanol. Preliminary analysis of the NMR data suggests folded structures for the glycopeptides.A preliminary account of this work was presented at an International Symposium held at the University of Alabama at Birmingham in November, 1994 on the occasion of the 65th birthday of Professor Lennart Rodén. 相似文献
93.
Expression of NADH-Dependent Glutamate Synthase in Response to the Supply of Nitrogen in Rice Cells in Suspension Culture 总被引:2,自引:0,他引:2
Watanabe Sachiko; Sakai Takahiro; Goto Satoshi; Yaginuma Toshiko; Hayakawa Toshihiko; Yamaya Tomoyuki 《Plant & cell physiology》1996,37(7):1034-1037
The effects of inorganic and organic nitrogen on the levelsof mRNA for NADH-dependent glutamate synthase (GOGAT) and theprotein were examined in rice cells in suspension culture. Asupply of NH+4, NO-3, glutamine, or asparagine induced the accumulationof the protein and mRNA, but levels of mRNA for ferredoxin-GOGATwere hardly affected.
1Present address: P.C. Center Wakuya-cho, Toda-gun, Miyagi,Japan. 相似文献
94.
Tokuma Yanai Haruaki Taniguchi Hiroki Sakai Kazunori Yoshida Naoto Kimura Akira Katou Yuji Oishi Toshiaki Masegi 《Journal of medical primatology》1996,25(4):309-312
Abstract: A rare case of bilateral adrenal myelolipomas in a female cotton-top tamarin is reported. Large bilateral masses in the adrenal glands were composed of mature adipose cells containing varying amounts of hematopoietic cells of the myeloid, erythroid, and megakaryocyte series. The gross and histologic features of this case closely resemble human “giant” adrenal myelolipomas. 相似文献
95.
Y. Sakai T. Abe Y. Ohbayashi K. Isaka K. Yamamoto Y. Tani N. Kato 《Applied microbiology》1996,62(7):2669-2672
When 7-aminocephalosporanic acid (7-ACA) was used as a single carbon source in the enrichment culture medium for screening 7-ACA-degrading microorganisms, pink yeast colonies appeared frequently, and these were identified as Rhodotorula glutinis. These intact R. glutinis cells converted (i) 7-ACA to deacetyl-7-ACA (7-ADACA) and (ii) monochloroacetyl-7-ACA to monochloroacetyl-7-ADACA at sufficiently high levels to be of commercial interest. Acetylation of 7-ADACA to 7-ACA, the reverse reaction of hydrolysis in an organic medium with methyl acetate as an acetyl donor, was also demonstrated. 相似文献
96.
Epstein-Barr virus nuclear antigen 2 exerts its transactivating function through interaction with recombination signal binding protein RBP-J kappa, the homologue of Drosophila Suppressor of Hairless. 总被引:23,自引:2,他引:21
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U Zimber-Strobl L J Strobl C Meitinger R Hinrichs T Sakai T Furukawa T Honjo G W Bornkamm 《The EMBO journal》1994,13(20):4973-4982
97.
Postnatal change in the distribution of actin filaments in endothelial cells was studied in the rat aorta by use of rhodamine-phalloidin staining and confocal laser scanning microscopy. Endothelial cells of the rat aorta possessed two populations of actin filament bundles, namely, peripheral bands at the cell border and stress fibers running longitudinally in the cytoplasm. Aortic endothelial cells of the neonatal rat contained only stress fibers, whereas those of the 10-day-old rat developed both peripheral bands and stress fibers. After 20 days of age, aortic endothelial cells had predominantly peripheral bands with occasional stress fibers around the branch orifices. During postnatal development the length density of stress fibers in aortic endothelial cells decreased, whereas individual stress fibers in endothelial cells were shortened. Electron-microscopic observation revealed that the high intercellular boundaries of aortic endothelial cells at birth decreased in height and developed cytoplasmic interdigitations after 20 days of age. The occurrence of peripheral bands at the cell border is thought to be closely related to formation of cytoplasmic interdigitation which strengthens the mechanical connection between endothelial cells against increasing transmural pressure. Expression of stress fibers in aortic endothelial cells of the neonatal rat is supposed to be affected by longitudinal elongation of the developing aorta, whereas their postnatal decrease is though to be correlated with the change of fluid shear stress loaded in the aortic endothelium. 相似文献
98.
In Vitro Bleaching of Hardwood Kraft Pulp by Extracellular Enzymes Excreted from White Rot Fungi in a Cultivation System Using a Membrane Filter 总被引:6,自引:4,他引:2
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To clarify the role of excreted extracellular enzymes during long-term incubation in a pulp biobleaching system with white rot fungi, we developed a cultivation system in which a membrane filter is used; this membrane filter can prevent direct contact between hyphae and kraft pulp, but allows extracellular enzymes to attack the kraft pulp. Phanerochaete sordida YK-624 brightened the pulp 21.4 points to 54.0% brightness after a 5-day in vitro treatment; this value was significantly higher than the values obtained with Phanerochaete chrysosporium and Coriolus versicolor after a 7-day treatment. Our results indicate that cell-free, membrane-filtered components from the in vitro bleaching system are capable of delignifying unbleached kraft pulp. Obvious candidates for filterable reagents capable of delignifying and bleaching kraft pulp are peroxidase and phenoloxidase proteins. The level of secreted manganese peroxidase activity in the filterable components was substantial during strain YK-624 in vitro bleaching. A positive correlation between the level of manganese peroxidase and brightening of the pulp was observed. 相似文献
99.
Cloning and characterization of a Pseudomonas aeruginosa gene involved in the negative regulation of phosphate taxis. 总被引:5,自引:3,他引:2
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Pseudomonas aeruginosa PAO1 exhibited a positive chemotactic response to P(i). The chemotactic response was induced by P(i) limitation. An alkaline phosphatase (AP) constitutive mutant showed a chemotactic response to P(i), regardless of whether the cells were starved for P(i). Sequence analysis and complementation studies showed that the P. aeruginosa phoU gene was involved both in the regulation of AP expression and in the induction of P(i) taxis. However, unlike AP expression, P(i) taxis was not regulated by the phoB gene product. 相似文献
100.
Sheldon Milstien Naoki Sakai Bruce J. Brew †Charles Krieger ‡James H. Vickers §Kuniaki Saito §Melvyn P. Heyes 《Journal of neurochemistry》1994,63(3):1178-1180
Abstract: Nitric oxide has been proposed to mediate cytotoxic effects in inflammatory diseases. To investigate the possibility that overproduction of nitric oxide might play a role in the neuropathology of inflammatory and noninflammatory neurological diseases, we compared levels of the markers of nitric oxide, nitrite plus nitrate, in the CSF of controls with those in patients with various neurologic diseases, including Huntington's and Alzheimer's disease, amyotrophic lateral sclerosis, and HIV infection. We found that there were no significant increases in the CSF levels of these nitric oxide metabolites, even in patients infected with HIV or in monkeys infected with poliovirus, both of which have significantly elevated levels of the neurotoxin quinolinic acid and the marker of macrophage activation, neopterin. However, CSF quinolinic acid, neopterin, and nitrite/nitrate levels were significantly increased in a small group of patients with bacterial and viral meningitis. 相似文献