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排序方式: 共有374条查询结果,搜索用时 15 毫秒
1.
Yoshimoto Ohta Kiichi Nishimura Yoshio Hirose 《Bioscience, biotechnology, and biochemistry》2013,77(1):5-9
Investigation has been carried out on the constituents of the monoterpene fraction of geranium oil from Pelargonium roseum Bourbon and, besides well-known components of the oil, some new components such as epoxylinalool, methyl heptenone, myrcene, limonene, p-cymene, citral and 2,2,6-trimethyl-6-vinyl-tetrahydropyran which was confirmed by deriving to cinenic acid, have been identified. 相似文献
2.
Yoshihide Shimabayashi Takao Takahashi Kiichi Iwamoto 《Bioscience, biotechnology, and biochemistry》2013,77(12):1673-1681
The devised method consists of the enzymatic hydrolysis, separation of deoxyribosides in the hydrolysate by paper chromatography and paper electrophoresis, and the estimation of the separated fractions with L. leichmannii. This method permits the determination of deoxyriboside composition of the smaller amounts of DNA or the related compounds with relatively higher accuracy even under the presence of some other compounds when nucleic acids and acid insoluble fractions of the chick embryo were analyzed.The change of each deoxyriboside composition in acid insoluble fraction prepared from the 3 to 19 day old embryos investigated by the method. Among the major four deoxyribosides, the contents of deoxyguanosine and of deoxycytidine was nearly constant during the development of the embryo, whereas that of thymidine and of deoxyadenosine appeared to undergo the change slightly at the periods from 10 to 15 days incubation. It seems that this periods is also the most active time of the synthesis of DNA and of the changes of deoxyribosyl compounds in acid soluble fraction through the embryo growth. 相似文献
3.
Takao Takahashi Noriko Yamada Kiichi Iwamoto Yoshihide Shimabayashi Kosaku Izutsu 《Bioscience, biotechnology, and biochemistry》2013,77(1):29-36
The phytohemagglutinin of rice seed has been purified by a sequence of steps involving fractionation with ammonium sulfate and successive chromatography on DEAE-and eMcellulose and finally gel filtration on Bio-Gel P-100. The purified rice seed hemagglutinin was shown to be homogeneous by electrophoresis on polyacrylamide gel and its molecular weight was 10,000, calculated from both the Ve/Vo value of gel filtration on Bio-Gel P-100 and the sum of the individual constituents (amino acids, sugars and metals). In addition to amino acid, the rice seed hemagglutinin contained 26.8% covalently bound carbohydrate which was identified and quantitated by gas chromatography of the acetylated alditols. Glucose was the predominant sugar with lesser amounts of glucosamine, xylose, and mannose also being present. And the rice seed hemagglutinin contained 1 g atom of calcium per molecule. The molecular weight of the rice seed hemagglutinin is smallest compared with some of phytohemagglutinins isolated from leguminous seeds and other plant sources. The rice seed hemagglutinin has the blastogenetic activity for human peripheral lymphocytes as well as Phaseolus vulgaris phytohemagglutinins or concanavalin A, jack bean hemagglutinin. 相似文献
4.
Background
To induce potent epitope-specific T cell immunity by a peptide-based vaccine, epitope peptides must be delivered efficiently to antigen-presenting cells (APCs) in vivo. Therefore, selecting an appropriate peptide carrier is crucial for the development of an effective peptide vaccine. In this study, we explored new peptide carriers which show enhancement in cytotoxic T lymphocyte (CTL) induction capability.Methodology/Principal Findings
Data from an epitope-specific in vivo CTL assay revealed that phosphatidylserine (PS) has a potent adjuvant effect among candidate materials tested. Further analyses showed that PS-conjugated antigens were preferentially and efficiently captured by professional APCs, in particular, by CD11c+CD11b+MHCII+ conventional dendritic cells (cDCs) compared to multilamellar liposome-conjugates or unconjugated antigens. In addition, PS demonstrated the stimulatory capacity of peptide-specific helper T cells in vivo.Conclusions/Significance
This work indicates that PS is the easily preparable efficient carrier with a simple structure that delivers antigen to professional APCs effectively and induce both helper and cytotoxic T cell responses in vivo. Therefore, PS is a promising novel adjuvant for T cell-inducing peptide vaccines. 相似文献5.
Chromosoma - The high-order structure of metaphase chromosomes remains still under investigation, especially the 30-nm structure that is still controversial. Advanced 3D imaging has provided useful... 相似文献
6.
We developed a microfluidic model of microcirculation containing both blood and lymphatic vessels for examining vascular permeability. The designed microfluidic device harbors upper and lower channels that are partly aligned and are separated by a porous membrane, and on this membrane, blood vascular endothelial cells (BECs) and lymphatic endothelial cells (LECs) were cocultured back-to-back. At cell-cell junctions of both BECs and LECs, claudin-5 and VE-cadherin were detected. The permeability coefficient measured here was lower than the value reported for isolated mammalian venules. Moreover, our results showed that the flow culture established in the device promoted the formation of endothelial cell-cell junctions, and that treatment with histamine, an inflammation-promoting substance, induced changes in the localization of tight and adherens junction-associated proteins and an increase in vascular permeability in the microdevice. These findings indicated that both BECs and LECs appeared to retain their functions in the microfluidic coculture platform. Using this microcirculation device, the vascular damage induced by habu snake venom was successfully assayed, and the assay time was reduced from 24 h to 30 min. This is the first report of a microcirculation model in which BECs and LECs were cocultured. Because the micromodel includes lymphatic vessels in addition to blood vessels, the model can be used to evaluate both vascular permeability and lymphatic return rate. 相似文献
7.
Masahiro Mishina Kiichi Ishiwata Mika Naganawa Yuichi Kimura Shin Kitamura Masahiko Suzuki Masaya Hashimoto Kenji Ishibashi Keiichi Oda Muneyuki Sakata Makoto Hamamoto Shiro Kobayashi Yasuo Katayama Kenji Ishii 《PloS one》2011,6(2)
Adenosine A2A receptors (A2ARs) are thought to interact negatively with the dopamine D2 receptor (D2R), so selective A2AR antagonists have attracted attention as novel treatments for Parkinson''s disease (PD). However, no information about the receptor in living patients with PD is available. The purpose of this study was to investigate the relationship between A2ARs and the dopaminergic system in the striata of drug-naïve PD patients and PD patients with dyskinesia, and alteration of these receptors after antiparkinsonian therapy. We measured binding ability of striatal A2ARs using positron emission tomography (PET) with [7-methyl-11C]-(E)-8-(3,4,5-trimethoxystyryl)-1,3,7-trimethylxanthine ([11C]TMSX) in nine drug-naïve patients with PD, seven PD patients with mild dyskinesia and six elderly control subjects using PET. The patients and eight normal control subjects were also examined for binding ability of dopamine transporters and D2Rs. Seven of the drug-naïve patients underwent a second series of PET scans following therapy. We found that the distribution volume ratio of A2ARs in the putamen were larger in the dyskinesic patients than in the control subjects (p<0.05, Tukey-Kramer post hoc test). In the drug-naïve patients, the binding ability of the A2ARs in the putamen, but not in the head of caudate nucleus, was significantly lower on the more affected side than on the less affected side (p<0.05, paired t-test). In addition, the A2ARs were significantly increased after antiparkinsonian therapy in the bilateral putamen of the drug-naïve patients (p<0.05, paired t-test) but not in the bilateral head of caudate nucleus. Our study demonstrated that the A2ARs in the putamen were increased in the PD patients with dyskinesia, and also suggest that the A2ARs in the putamen compensate for the asymmetrical decrease of dopamine in drug-naïve PD patients and that antiparkinsonian therapy increases the A2ARs in the putamen. The A2ARs may play an important role in regulation of parkinsonism in PD. 相似文献
8.
Naruemon Khemkladngoen Joyce A. Cartagena Kiichi Fukui 《Plant biotechnology reports》2011,5(3):235-243
The non-edible plant Jatropha curcas L. is one of the most promising feedstock for sustainable biodiesel production as it is not a source of edible vegetable
oils, produces high amounts of oil (approx. 30–60% in dry seeds) and does not require high-cost maintenance. However, as
with other undomesticated crops, the cultivation of J. curcas presents several drawbacks, such as low productivity and susceptibility to pests. Hence, varietal improvement by genetic
engineering is essential if J. curcas is to become a viable alternative source of biodiesel. There is to date no well-established and efficient transformation system
for J. curcas. In this study, we tested various physical wounding treatments, such as sonication and sand-vortexing, with the aim of developing
an efficient Agrobacterium-mediated transformation for J. curcas. The highest stable transformation rate (53%) was achieved when explants were subjected to 1 min of sonication followed by
9 min of shaking in Agrobacterium suspension. The transformation frequency achieved using this protocol is the highest yet reported for J. curcas. 相似文献
9.
Hisamitsu Ide Yan Lu Jingsong Yu Takahiro Noguchi Mayuko Kanayama Satoru Muto Raizo Yamaguchi Suguru Kawato Shigeo Horie 《Human cell》2017,30(2):133-139
There is now mounting evidence that the aryl hydrocarbon receptor (AhR) plays an important role in physiologic responses such as development, cell cycle regulation, immune function and also malignant transformation in various tissues. The strong nuclear AhR expression is observed in the invasive phenotype, and an elevated nuclear AhR expression is associated with a poor prognosis of human prostate cancer. On the other hand, there are conflicting results that the AhR deficiency results in increased susceptibility to prostate tumors in mouse model. In the present study, we investigated AhR expression and its role in the growth and invasiveness of human prostate cancer cells. The AhR protein expression was detected in prostate cancer cell lines and human prostate cancer tissues. A small interfering RNA targeting AhR, constitutive active AhR expression vector, and AhR agonist and antagonist were used to moderate its expression and signaling. The induction of AhR signaling attenuated invasiveness of prostate cancer cells without affecting the cellular growth rate. These results suggest that AhR signaling in prostate cancer cells facilitates invasion of these cells, and modulation with this signaling can be a potential therapeutic target of invasive tumors. 相似文献
10.