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871.
872.
Owhashi M Matsumoto J Imase A Kirinoki M Kitikoon V Chigusa Y Matsuda H 《Experimental parasitology》2005,110(4):335-341
Schistosoma mekongi causes granulomatous lesions around eggs deposited in the liver with neutrophil-rich inflammatory reactions in the early stage of the egg laying. To define the aspects of the typical pathogenesis of S. mekongi infection, we determined the difference between soluble egg antigen (SEA) from S. mekongi and S. japonicum with a focus on chemotactic factors for neutrophils or eosinophils. Mean volume and protein amount of S. mekongi eggs was 71 and 58% of those of Schistosoma japonicum eggs, respectively. Neutrophil chemotactic activity of S. mekongi SEA was about two times higher than that of S. japonicum. In contrast, eosinophil chemotactic activity of S. mekongi SEA was about half of that of S. japonicum SEA. Molecular analysis revealed that S. mekongi SEA contains higher molecular-weight components with a lower level of glycosylation, and this is likely to be related to the intense neutrophil chemotactic activity in comparison with S. japonicum SEA. The prominent chemotactic reactivity for neutrophils is likely to be involved in the typical pathogenesis of mekongi schistosomiasis. 相似文献
873.
Abe Y Hara K Matsumoto H Kobayashi J Sasada H Ekwall H Rodriguez-Martinez H Sato E 《Biology of reproduction》2005,72(6):1416-1420
To improve the feasibility of nylon-mesh holder for vitrification of bovine cumulus-oocytes complexes (GV-COCs) having germinal vesicle, this study was conducted to demonstrate effects of sugars and protocol of exposure in vitrification on subsequent in vitro maturation, ultrastructural changes, and in vitro development in bovine immature oocytes after cryopreservation using nylon mesh. Before vitrification, GV-COCs were exposed to the cryoprotectant, which was composed of 40% (v/v) ethylene glycol, 18% (w/v) Ficoll-70, and 0.3 M sucrose (EFS40) or 0.3 M trehalose (EFT40), either by single step or in a stepwise way. The maturation rates in the stepwise exposure with EFS40 or EFT40 were significantly higher (P < 0.05) compared with the corresponding rates in the single step. In the stepwise exposure, few abnormalities were observed compared with the single-step exposure, where most oocytes showed a highly vacuolated cytoplasm with many ruptured mitochondria. Cleavage rates in fertilized oocytes previously exposed stepwise to EFS40 or EFT40 were significantly higher than those exposed by the single-step procedure. The cleaved embryos derived from the stepwise exposure to EFS40 developed to blastocysts. After transfer of blastocysts derived from vitrified GV oocytes, a female calf was born. These results indicate that vitrification of large numbers of bovine GV-COCs using a nylon-mesh holder accompanied with stepwise exposure minimizes structural damage in organelles, resulting in yield of viable blastocysts following in vitro embryo production. 相似文献
874.
Hashimoto T Matsumoto MM Li JF Lawton MT Young WL;University of California San Francisco BAVM Study Group 《BMC neurology》2005,5(1):1
Background
The primary aim of this study is to demonstrate the feasibility of utilizing doxycycline to suppress matrix metalloproteinase-9 (MMP-9) in brain arteriovenous malformations (AVMs). 相似文献875.
Matsumoto K Nagao R Murata T Arai Y Kichise T Nakashita H Taguchi S Shimada H Doi Y 《Biomacromolecules》2005,6(4):2126-2130
In this study, the enhancement of photosynthetic PHA production was achieved using the highly active mutants of PHA synthase created by the in vitro evolutionally techniques. The wild-type and mutated PHA synthase genes from Aeromonas caviae were introduced into Arabidopsis thaliana together with the NADPH-dependent acetoacetyl-CoA reductase gene from Ralstonia eutropha. Expression of the highly active mutated PHA synthase genes, N149S and D171G, led to an 8-10-fold increase in PHA content in the T1 transgenic Arabidopsis, compared to plants harboring the wild-type PHA synthase gene. In homozygous T2 progenies, PHA content was further increased up to 6.1 mg/g cell dry weight. GC/MS analysis of the purified PHA from the transformants revealed that these PHAs were poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] copolymers consisting of 0.2-0.8 mol % 3HV. The monomer composition of the P(3HB-co-3HV) copolymers synthesized by the wild-type and mutated PHA synthases reflected the substrate specificities observed in Escherichia coli. These results indicate that in vitro evolved PHA synthases can enhance the productivity of PHA and regulate the monomer composition in transgenic plants. 相似文献
876.
Cheng CH Chung MC Liu SM Chen SK Kao FY Lin SJ Hsiao SH Tseng IC Hsing YI Wu HP Chen CS Shaw JF Wu J Matsumoto T Sasaki T Chen HH Chow TY 《Molecular genetics and genomics : MGG》2005,274(4):337-345
A fine physical map of the rice (Oryza sativa spp. Japonica var. Nipponbare) chromosome 5 with bacterial artificial chromosome (BAC) and PI-derived artificial chromosome (PAC) clones
was constructed through integration of 280 sequenced BAC/PAC clones and 232 sequence tagged site/expressed sequence tag markers
with the use of fingerprinted contig data of the Nipponbare genome. This map consists of five contigs covering 99% of the
estimated chromosome size (30.08 Mb). The four physical gaps were estimated at 30 and 20 kb for gaps 1–3 and gap 4, respectively.
We have submitted 42.2-Mb sequences with 29.8 Mb of nonoverlapping sequences to public databases. BAC clones corresponding
to telomere and centromere regions were confirmed by BAC-fluorescence in situ hybridization (FISH) on a pachytene chromosome.
The genetically centromeric region at 54.6 cM was covered by a minimum tiling path spanning 2.1 Mb with no physical gaps.
The precise position of the centromere was revealed by using three overlapping BAC/PACs for ~150 kb. In addition, FISH results
revealed uneven chromatin condensation around the centromeric region at the pachytene stage. This map is of use for positional
cloning and further characterization of the rice functional genomics.
Electronic supplementary material Supplementary material is available in the online version of this article at
and is accessible for authorized users.
Chia-Hsiung Cheng and Mei-Chu Chung have equal contributions. 相似文献
877.
Large-scale analysis of the human ubiquitin-related proteome 总被引:1,自引:0,他引:1
Protein ubiquitylation contributes to the regulation of many cellular processes including protein degradation, receptor internalization, and repair of DNA damage. We now present a comprehensive characterization of ubiquitin-conjugated and ubiquitin-associated proteins in human cells. The proteins were purified by immunoaffinity chromatography under denaturing or native conditions. They were then digested with trypsin, and the resulting peptides were analyzed by 2-D LC and MS/MS. A total of 670 distinct proteins were identified; 345 proteins (51%) were classified as Urp-D (ubiquitin-related proteome under the denaturing condition) and comprised ubiquitin-conjugated molecules, whereas 325 proteins (49%) were classified as Urp-N (ubiquitin-related proteome only under the native condition) and included molecules that associated with ubiquitylated proteins. The proportions of proteins in various functional categories differed substantially between Urp-D and Urp-N. Many ribosomal subunits were detected in the Urp-D group of proteins and several of these subunits were directly shown to be ubiquitylated by mass spectrometric analysis, suggesting that ubiquitylation might play an important role in the regulation and/or quality control of ribosomal proteins. Our results demonstrate the potential of proteomics analysis of protein ubiquitylation to provide important insight into the regulation of protein stability and other ubiquitin-related cellular functions. 相似文献
878.
Enami I Suzuki T Tada O Nakada Y Nakamura K Tohri A Ohta H Inoue I Shen JR 《The FEBS journal》2005,272(19):5020-5030
Distribution of photosystem II (PSII) extrinsic proteins was examined using antibodies raised against various extrinsic proteins from different sources. The results showed that a glaucophyte (Cyanophora paradoxa) having the most primitive plastids contained the cyanobacterial-type extrinsic proteins (PsbO, PsbV, PsbU), and the primitive red algae (Cyanidium caldarium) contained the red algal-type extrinsic proteins (PsO, PsbQ', PsbV, PsbU), whereas a prasinophyte (Pyraminonas parkeae), which is one of the most primitive green algae, contained the green algal-type ones (PsbO, PsbP, PsbQ). These suggest that the extrinsic proteins had been diverged into cyanobacterial-, red algal- and green algal-types during early phases of evolution after a primary endosymbiosis. This study also showed that a haptophyte, diatoms and brown algae, which resulted from red algal secondary endosymbiosis, contained the red algal-type, whereas Euglena gracilis resulted from green algal secondary endosymbiosis contained the green algal-type extrinsic proteins, suggesting that the red algal- and green algal-type extrinsic proteins have been retained unchanged in the different lines of organisms following the secondary endosymbiosis. Based on these immunological analyses, together with the current genome data, the evolution of photosynthetic oxygen-evolving PSII was discussed from a view of distribution of the extrinsic proteins, and a new model for the evolution of the PSII extrinsic proteins was proposed. 相似文献
879.
880.
Study of androgen receptor functions by genetic models 总被引:2,自引:0,他引:2