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101.
102.
Serrano-Luna Jde J Cervantes-Sandoval I Calderón J Navarro-García F Tsutsumi V Shibayama M 《Canadian journal of microbiology》2006,52(1):16-23
Acanthamoeba spp. are free-living amoebae that cause amoebic granulomatous encephalitis, skin lesions, and ocular amoebic keratitis in humans. Several authors have suggested that proteases could play a role in the pathogenesis of these diseases. In the present work, we performed a partial biochemical characterization of proteases in crude extracts of Acanthamoeba spp. and in conditioned medium using 7.5% SDS-PAGE copolymerized with 0.1% m/v gelatin as substrate. We distinguished a total of 17 bands with proteolytic activity distributed in two species of Acanthamoeba. The bands ranged from 30 to 188 kDa in A. castellanii and from 34 to 144 kDa in A. polyphaga. Additionally, we showed that the pattern of protease activity differed in the two species of Acanthamoeba when pH was altered. By using protease inhibitors, we found that the proteolytic activities belonged mostly to the serine protease family and secondly to cysteine proteases and that the proteolytic activities from A. castellanii were higher than those in A. polyphaga. Furthermore, aprotinin was found to inhibit crude extract protease activity on Madin-Darby canine kidney (MDCK) monolayers. These data suggest that protease patterns could be more complex than previously reported. 相似文献
103.
HCV core protein localizes in the nuclei of nonparenchymal liver cells from chronically HCV-infected patients 总被引:3,自引:0,他引:3
Falcón V Acosta-Rivero N Shibayama M Chinea G Gavilondo JV de la Rosa MC Menéndez I Gra B Dueñas-Carrera S Viña A García W González-Bravo M Luna-Munoz J Miranda-Sanchez M Morales-Grillo J Kouri J Tsutsumi V 《Biochemical and biophysical research communications》2005,329(4):1320-1328
Understanding the mechanism of hepatitis C virus (HCV) pathogenesis is an important part of HCV research. Recent experimental evidence suggests that the HCV core protein (HCcAg) has numerous functional activities. These properties suggest that HCcAg, in concert with cellular factors, may contribute to pathogenesis during persistent HCV infection. HCV is capable of infecting cells other than hepatocytes. Although the extrahepatic cellular tropism of HCV may play a role in the pathophysiology of this infection, the precise biological significance of the presence of HCV components in different liver cell types presently remains to be established. In this study, HCcAg was detected in nonparenchymal liver cells of six patients out of eight positive for serum HCV RNA. Immunostaining with anti-HCcAg mAbs revealed the presence of this protein in different liver cell types such as lymphocytes, Kupffer, polymorphonuclear, pit, endothelial, stellate, and fibroblast-like cells. Interestingly, HCcAg was immunolabeled not only in the cytoplasm but also in the nucleus of these cells. Remarkably, HCcAg co-localized with large lipid droplets present in stellate cells and with collagen fibers in the extracellular matrix. Moreover, HCcAg was immunolabeled in bile canaliculus suggesting the involvement of the biliary system in the pathobiology of HCV. Data suggest that nonparenchymal liver cells may constitute a reservoir for HCV replication. Besides, HCcAg may contribute to modulate immune function and fibrosis in the liver as well as steatosis. 相似文献
104.
The constituents of Virola carinata were established as dehydrodieugenol, its monomethyl ether and sitosterol. 相似文献
105.
Cho EM Okada A Kenmoku H Otomo K Toyomasu T Mitsuhashi W Sassa T Yajima A Yabuta G Mori K Oikawa H Toshima H Shibuya N Nojiri H Omori T Nishiyama M Yamane H 《The Plant journal : for cell and molecular biology》2004,37(1):1-8
We have isolated and characterized a cDNA encoding a novel diterpene cyclase, OsDTC1, from suspension-cultured rice cells treated with a chitin elicitor. OsDTC1 functions as ent-cassa-12,15-diene synthase, which is considered to play a key role in the biosynthesis of (-)-phytocassanes recently isolated as rice diterpenoid phytoalexins. The expression of OsDTC1 mRNA was also confirmed in ultraviolet (UV)-irradiated rice leaves. In addition, we identified ent-cassa-12,15-diene, a putative diterpene hydrocarbon precursor of (-)-phytocassanes, as an endogenous compound in the chitin-elicited suspension-cultured rice cells and the UV-irradiated rice leaves. The OsDTC1 cDNA isolated here will be a useful tool to investigate the regulatory mechanisms of the biosynthesis of (-)-phytocassanes in rice. 相似文献
106.
107.
Masatomo Kimura Kazuko Nishimura Eisuke Enoki Takaaki Chikugo Osamu Maenishi 《Mycopathologia》2012,174(5-6):441-450
Hyphae are usually the only fungal elements found in tissue of mucormycosis, and other fungal elements are quite rarely encountered. We found chlamydospores in bronchial lumina in autopsied tissue of pulmonary mucormycosis of a diabetic patient. Chlamydospores are thick-walled, asexually produced spores arising from the modification of a hyphal segment. This is the first histologic demonstration of chlamydospores in mucormycosis in which the causative fungus is culturally identified to species level. Rhizopus microsporus var. rhizopodiformis was isolated from the present autopsied pulmonary tissue. A literature review of human infection by this fungus found 27 cases with histopathologic evidence. 相似文献
108.
109.
Takenaka M Nanayama K Isobe S Murata M 《Bioscience, biotechnology, and biochemistry》2006,70(1):172-177
There was an obvious decrease in caffeic acid derivatives during the boiling of cube-shaped blocks of sweet potatoes. They also decreased in a mixture of freeze-dried sweet-potato powder and water maintained at room temperature. Ascorbic acid prevented the decrease, supporting the occurrence of an enzyme reaction with polyphenol oxidase (PPO). 5-O-Caffeoylquinic acid (5-CQA, "3-O-caffeoylquinic acid" as a trivial name) and 3,5-di-O-caffeoylquinic acid (3,5-CQA), major phenolic compounds of sweet potato, did not change when they were separately heated in boiling water. When the mixture of powdered sweet potato and water was heated at 100 degrees C, there was only a negligible decrease in the total amount of phenolic compounds, and portions of 5-CQA and 3,5-CQA were found to be isomerized to 3-CQA, 4-CQA, 3,4-CQA, and 4,5-CQA. The content and composition of the phenolic compounds in sweet potatoes differed between fresh and long-stored ones, as did their response to heating. 相似文献
110.
Takuto Kojima Yasutomi Asano Osamu Kurasawa Yasuhiro Hirata Naoki Iwamura Tzu-Tshin Wong Bunnai Saito Yuta Tanaka Ryosuke Arai Kazuko Yonemori Yasufumi Miyamoto Yoji Sagiya Masahiro Yaguchi Sachio Shibata Akio Mizutani Osamu Sano Ryutaro Adachi Yoshinori Satomi Shinichi Imamura 《Bioorganic & medicinal chemistry》2018,26(9):2452-2465
We pursued serine palmitoyltransferase (SPT) inhibitors as novel cancer therapeutic agents based on a correlation between SPT inhibition and growth suppression of cancer cells. High-throughput screening and medicinal chemistry efforts led to the identification of structurally diverse SPT inhibitors 4 and 5. Both compounds potently inhibited SPT enzyme and decreased intracellular ceramide content. In addition, they suppressed cell growth of human lung adenocarcinoma HCC4006 and acute promyelocytic leukemia PL-21, and displayed good pharmacokinetic profiles. Reduction of 3-ketodihydrosphingosine, the direct downstream product of SPT, was confirmed under in vivo settings after oral administration of compounds 4 and 5. Their anti-tumor efficacy was observed in a PL-21 xenograft mouse model. These results suggested that SPT inhibitors might have potential to be effective cancer therapeutics. 相似文献