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81.
Keizo Yonemori Chitose Honsho Shinya Kanzaki Hitofumi Ino Ayako Ikegami Akira Kitajima Akira Sugiura Dan E. Parfitt 《Tree Genetics & Genomes》2008,4(2):149-158
To elucidate the relationships among Diospyros kaki and species closely related in previous studies, the nuclear ribosomal internal transcribed spacer (ITS) DNA sequence and
the chloroplast matK gene were sequenced and compared with those of nine Diospyros species from Thailand, four species from temperate regions, and one species of southern Africa, D. lycioides. Maximum parsimony, maximum likelihood, and neighbor joining analyses of the matK and ITS data sets revealed that D. kaki is closely related to two diploid species, D. oleifera and D. glandulosa. D. kaki, D. glandulosa, and D. oleifera were placed differently in the trees obtained from ITS and matK data sets, suggesting that hybridization and/or introgression may have occurred during the development of these species.
D. kaki was not found to be closely related to D. ehretioides, a diploid species from Thailand. These results differed from a prior analysis of this genus performed with chloroplast DNA
(cpDNA) restriction site mutations in 3.2- and 2.1-kb amplified sequences. The results supported Ng’s hypothesis that D. glandulosa and D. kaki may share a common ancestor. D. oleifera was also closely associated with D. kaki. 相似文献
82.
Yoshida Y Suzuki K Yamamoto A Sakai N Bando M Tanimoto K Yamaguchi Y Sakaguchi T Akhter H Fujii G Yoshimura S Ogata S Sohda M Misumi Y Nakamura N 《Experimental cell research》2008,314(19):3427-3443
Yip1p/Yif1p family proteins are five-span transmembrane proteins localized in the Golgi apparatus and the ER. There are nine family members in humans, and YIPF5 and YIF1A are the human orthologs of budding yeast Yip1p and Yif1p, respectively. We raised antisera against YIPF5 and YIF1A and examined the localization of endogenous proteins in HeLa cells. Immunofluorescence, immunoelectron microscopy and subcellular fractionation analysis suggested that YIPF5 and YIF1A are not restricted to ER exit sites but also localized in the ER-Golgi intermediate compartment (ERGIC) and some in the cis-Golgi at steady state. Along with ERGIC53, YIPF5 and YIF1A remained in the cytoplasmic punctate structures after brefeldin A treatment, accumulated in the ERGIC and the cis-Golgi after treatment with AlF4- and accumulated in the ER when ER to Golgi transport was inhibited by Sar1(H79G). These results supported the localization of YIPF5 and YIF1A in the ERGIC and the cis-Golgi, and strongly suggested that they are recycling between the ER and the Golgi apparatus. Analysis by blue native PAGE and co-immunoprecipitation showed that YIPF5 and YIF1A form stable complexes of three different sizes. Interestingly, the knockdown of YIPF5 or YIF1A caused partial disassembly of the Golgi apparatus suggesting that YIPF5 and YIF1A are involved in the maintenance of the Golgi structure. 相似文献
83.
Misumi S Eto A Mitsumata R Yamada M Takamune N Shoji S 《Biochemical and biophysical research communications》2008,377(2):617-621
Our previous study demonstrated that the immunization with a cycloimmunogen derived from extracellular loop-2 (ECL-2) of CCR5 (cDDR5) attenuated acute phase of CCR5-tropic simian-human immunodeficiency virus (SHIV)SF162P3 replication in vivo. Although the study showed that the antisera raised against cDDR5 reacted with cell-expressed CCR5, we have not yet demonstrated whether the antisera can react with virion-incorporated CCR5. Here, we show that rhesus cDDR5 (rcDDR5)-specific antibodies react with not only cell-expressed but also virion-incorporated simian CCR5s (siCCR5s), but may predominantly exert their inhibitory effects on simian immunodeficiency virus (SIV) infection by the binding of cell-expressed rather than virion-incorporated CCR5s. These results suggest that the virion-incorporated CCR5 may contribute to the reactivation of the anti-rcDDR5 antibody-producing B-cells by SIV particles after rcDDR5 immunization, although the binding of anti-rcDDR5 antibody to virion-incorporated CCR5 results in a partial inhibitory effect on SIV infection. 相似文献
84.
Karakawa T Sato K Muramoto Y Mitani Y Kitamado M Iwanaga T Nabeshima T Maruyama K Nakagawa K Ishida K Sasamoto K 《Biochemical and biophysical research communications》2008,370(1):93-97
Electron spin resonance using spin-trapping is a useful technique for detecting direct reactive oxygen species, such as superoxide (). However, the widely used spin trap 2,2-dimethyl-3,4-dihydro-2H-pyrrole N-oxide (DMPO) has several fundamental limitations in terms of half-life and stability. Recently, the new spin trap 2-diphenylphosphinoyl-2-methyl-3,4-dihydro-2H-pyrrole N-oxide (DPhPMPO) was developed by us. We evaluated the biological applicability of DPhPMPO to analyze in both cell-free and cellular systems. DPhPMPO had a larger rate constant for and formed more stable spin adducts for than DMPO in the xanthine/xanthine oxidase (X/XO) system. In the phorbol myristate acetate-activated neutrophil system, the detection potential of DPhPMPO for was significantly higher than that of DMPO (kDMPO = 13.95 M−1 s−1, kDPhPMPO = 42.4 M−1 s−1). These results indicated that DPhPMPO is a potentially good candidate for trapping in a biological system. 相似文献
85.
Uptake and recovery of gold ions from electroplating wastes using eggshell membrane. 总被引:5,自引:0,他引:5
Shin-ichi Ishikawa Kyozo Suyama Keizo Arihara Makoto Itoh 《Bioresource technology》2002,81(3):201-206
The animal byproduct, hen eggshell membrane (ESM), was evaluated for its ability to sorb gold ions (dicyanoaurate(I) and tetrachloroaurate(III)) from solutions and electroplating wastewater. The gold uptake was dependent on pH, temperature and co-ions present in the solutions, with pH 3.0 being the optimum value. The equilibrium data followed the Langmuir isotherm model with maximum capacities of 147 mg Au(I)/g dry weight and 618 mg Au(III)/g, respectively. Desorption of sorbed gold(I) with 0.1 mol/l NaOH resulted in no changes of the biosorbent gold uptake capacity through five consecutive sorption/desorption cycles. In column experiments, selective recovery of gold from electroplating wastewater containing various metal ions was noted. The affinity of metal sorption was in the order Au > Ag > Co > Cu > Pb > Ni > Zn. 相似文献
86.
Chlamydomonas is an unicellular green alga that contains one cup-shaped chloroplast with about 60 copies of cpDNA. Chloroplasts (cp) multiply
in the cytoplasm of the plant cell by binary division, with multiple copies of cpDNA transmitted and maintained in successive
generations. The effect of cpDNA copy number on cell proliferation and aging was investigated using a C. reinhardtii moc mutant, which has an undispersed cp-nucleoid and unequal segregation of cpDNA during cell division. When the mother cell
divided into four daughters, one moc daughter cell chloroplast contained about 60 copies of cpDNA, and the chloroplasts in the three other daughter cells contained
the 4–7 copies of cpDNA. In liquid medium, the number of moc cells at the period of stationary phase was about one-third that of the wild type. To observe the process of proliferation
and aging in the mother cell, we used solid medium. Three out of four moc cell spores were preferentially degenerated 60 days after cell transfer. To confirm this, wild-type and moc mother cells containing four daughter cells were treated with novobiocin to inhibit cpDNA replication. Cell degeneration
increased only in the moc strain following novobiocin introduction. In total, our results suggest that cells possessing smaller amounts of cpDNA degenerate
and age more rapidly.
Received 7 September 2000/ Accepted in revised form 14 February 2001 相似文献
87.
The specificity of the action of polymyxin B was studied using liposomes as a model membrane system. Liposomes prepared from total lipids of Gram-negative bacteria Escherichia coli, a mixture of purified E. coli phosphatidylethanolamine and cardiolipin and a mixture of phosphatidylethanolamine and phosphatidylglycerol, were extremely sensitive to polymyxin while those prepared from lipids of Gram-positive bacteria Streptococcus sanguis, lipids of sheep erythrocyte membranes, mixtures of egg lecithin and negatively charged amphiphatic molecules, were less sensitive to the action of the antibiotic. Chlolesterol was shown to suppress the polymyxin-induced response in liposomes. 相似文献
88.
Koji Ashizawa Etsuko Tamiya Keizo Okauchi Hisayoshi Nishiyama 《Animal reproduction science》1985,9(2):181-188
Fowl spermatozoa were incubated at 41°C in a supernatant removed from a 4-day culture medium of embryonic chick skeletal muscle cells. Their motility, as assessed at room temperature (20–25°C), was maintained for 48 h. Fertilizing ability was also retained for at least 24 h. In contrast, spermatozoa incubated in the fresh culture medium lost their motility and fertilizing ability rapidly. A filtrate of the 4-day culture medium, obtained by passing the fluid through an Amicon PM-10 ultrafiltration membrane, prolonged the motility of spermatozoa. These results suggested that a low molecular weight factor(s) (mol. wt. < 10 000) supplied by the cultured cells effectively prolonged the motility of spermatozoa. 相似文献
89.
Resistance of staphylococci to desiccation, dry heat, wet heat and ultraviolet irradiation was studied using 128 strains obtained from patients in our surgical clinics. Staphylococci of phage group I including type 81, particularly of type 80/81, showed significantly high death rates after desiccation, dry heating, and wet heating, and significantly low death rates after ultraviolet irradiation. In contrast, group-II strains responded inversely to these physical agents. The mean death rate of group-III strains approximated that of group I after desiccation, dry heating, and ultraviolet irradiation, but after wet heating it was lower than that of group II. The results indicate that transmissibility of staphylococci might be influenced to a great extent by physical factors in the environment outside the body. 相似文献
90.
Determination of
Ichiro Ono Keizo Matsuda Sachiko Kanno 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1997,692(2)
A simple, rapid and sensitive two column-switching high-performance liquid chromatographic (HPLC) method with ultraviolet detection at 210 nm has been developed for the determination of
(AY4166, I) and its seven metabolites in human plasma and urine. Measurements of I and its metabolites were carried out by two column-switching HPLC, because metabolites were classified into two groups according to their retention times. After purification of plasma samples using solid-phase extraction and direct dilution of urinary samples, I and each metabolite were injected into HPLC. The calibration graphs for plasma and urinary samples were linear in the ranges 0.1 to 10 μg ml−1 and 0.5 to 50 μg ml−1, respectively. Recoveries of I and its seven metabolites were over 88% by the standard addition method and the relative standard deviations of I and its metabolites were 1–6%. 相似文献
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