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91.
92.
Ohtsubo T Ohya Y Nakamura Y Kansui Y Furuichi M Matsumura K Fujii K Iida M Nakabeppu Y 《DNA Repair》2007,6(6):760-769
Accumulation of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxo-dG) in DNA is associated with mutagenesis and cell death. Little attention has been given to the biological significance of 8-oxo-dG accumulation in cardiovascular tissues during the different stage of hypertension and its prevention. We thus investigated the levels and localization of both 8-oxo-dG accumulation and expression of MTH1, which hydrolyzes 8-oxo-dGTP to prevent its incorporation into DNA, in the thoracic aorta prepared from stroke-prone spontaneously hypertensive rats (SHRSP) and age-matched Wister-Kyoto rats (WKY), aged 5-32 weeks. HPLC-MS/MS analysis revealed that the levels of nuclear 8-oxo-dG in the aorta increased significantly in SHRSP, but not WKY, with aging. Immunohistochemical study revealed that both TUNEL reactivity and 8-oxo-dG immunoreactivity were increased in smooth muscle cells (SMC) and endothelial cells (EC) of the aorta with aging, and they exhibited similar distributions in serial sections. The number of 8-oxo-dG and TUNEL positive cells in EC, but not in SMC, was significantly higher in SHRSP than WKY at 32 weeks of age. In contrast, the expression levels of Mth1mRNA and MTH1 protein in the aorta were similarly decreased both in SHRSP and WKY with aging. However, the number of MTH1 expressing EC was remarkably increased in the older SHRSP compared to the younger ones or age-matched WKY. Hypertension significantly increased not only 8-oxo-dG accumulation but also the expression of MTH1 in EC of the aorta during aging. While accumulation of 8-oxo-dG in SMC of the aorta was slightly increased, the expression of MTH1 protein in SMC was rather decreased by hypertension. We thus suggest that MTH1 may protect EC in the aorta from the oxidative damage increased by hypertension. 相似文献
93.
Recently we reported that Catalase-1 (CAT-1) played an important role in protecting conidial viability in Neurospora crassa, and interacted with a light signal transducer, nucleoside diphosphate kinase-1 (NDK-1). To disclose the functional interaction
between CAT-1 and NDK-1 at the genetic level, we created CAT-1 and NDK-1 double mutants, cat-1;ndk-1-1 and cat-1;ndk-1-2, by crossing single mutants of cat-1
RIP
and ndk-1
P72H
previously isolated in our laboratory. The double mutant strains grew normally, but showed increased CAT-2 activity. In cat-1
RIP
, NDK activity was increased when dCDP was used as a substrate. ndk-1
P72H
, cat-1;ndk-1-1, and cat-1;ndk-1-2 were more sensitive to riboflavin than the wild type and cat-1
RIP
under strong light (100 μE m−2 s−1). The pull-down experiment suggests that His-tagged NDK-1 is bound to [32P]NADH. However, his-tagged NDK-1P72H was not bound to [32P]NADH. The double mutants showed much lower conidial viability and lost all conidial germination ability much more rapidly
than cat-1
RIP
, when they were cultured under continuous light for more than 2 weeks. These results indicate that the interaction of CAT-1
with NDK-1 plays an important role in supporting the survival of conidia under oxidative and light-induced stress including
singlet oxygen, and confirm our former conclusion that reactive oxygen species play an important role in light signal transduction
via NDK-1 at the genetic level.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
94.
Hiroyuki Nakamura Jong-Dae Lee Manabu Ueno Yusuke Miyajima Hyun Seung Ban 《NanoBioTechnology》2007,3(2):135-145
High accumulation and selective delivery of boron into tumor tissues are the most important requirements to achieve efficient
neutron capture therapy of cancers. We focused on liposomal boron delivery system to achieve a large amount of boron delivery
to tumor. We succeeded in the synthesis of the double-tailed boron cluster lipids 4a–c and 5a–c, which has a B12H11S-moiety as a hydrophilic function, by S-alkylation of B12H11SH with bromoacetyl and chloroacetocarbamate derivatives of diacylglycerols. Size distribution of liposomes prepared from
the boron cluster lipid 4b, dimyristoylphosphatidylcholine, polyethyleneglycol-conjugated distearoylphosphatidylethanolamine, and cholesterol was determined
as 100 nm in diameter by an electrophoretic light scattering spectrophotometer. Calcein-encapsulation experiments revealed
that these boronated liposomes are stable at 37 °C in fetal bovine serum solution for 24 h. 相似文献
95.
Kijima Yusuke Wantong Wang Igarashi Yoji Yoshitake Kazutoshi Asakawa Shuichi Suzuki Yutaka Watabe Shugo Kinoshita Shigeharu 《Marine biotechnology (New York, N.Y.)》2022,24(5):895-910
Marine Biotechnology - Most mammals, including humans, show obvious aging phenotypes, for example, loss of tissue plasticity and sarcopenia. In this regard, fish can be attractive models to study... 相似文献
96.
Ichthyological Research - Two types of ophichthid larvae collected from Japanese coastal waters around Kyushu and Shikoku were identified by DNA barcoding as Ophichthus celebicus (Bleeker 1856) and... 相似文献
97.
Lou Yuting Kawaue Takumi Yow Ivan Toyama Yusuke Prost Jacques Hiraiwa Tetsuya 《Biomechanics and modeling in mechanobiology》2022,21(5):1511-1530
Biomechanics and Modeling in Mechanobiology - Tissue layers can generally slide at the interface, accompanied by the dissipation due to friction. Nevertheless, it remains elusive how force could... 相似文献
98.
99.
100.
Yusuke Mizokami Ko Noguchi Mikiko Kojima Hitoshi Sakakibara Ichiro Terashima 《Plant, cell & environment》2019,42(4):1257-1269
C3 photosynthesis is often limited by CO2 diffusivity or stomatal (gs) and mesophyll (gm) conductances. To characterize effects of stomatal closure induced by either high CO2 or abscisic acid (ABA) application on gm, we examined gs and gm in the wild type (Col‐0) and ost1 and slac1‐2 mutants of Arabidopsis thaliana grown at 390 or 780 μmol mol?1 CO2. Stomata of these mutants were reported to be insensitive to both high CO2 and ABA. When the ambient CO2 increased instantaneously, gm decreased in all these plants, whereas gs in ost1 and slac1‐2 was unchanged. Therefore, the decrease in gm in response to high CO2 occurred irrespective of the responses of gs. gm was mainly determined by the instantaneous CO2 concentration during the measurement and not markedly by the CO2 concentration during the growth. Exogenous application of ABA to Col‐0 caused the decrease in the intercellular CO2 concentration (Ci). With the decrease in Ci, gm did not increase but decreased, indicating that the response of gm to CO2 and that to ABA are differently regulated and that ABA content in the leaves plays an important role in the regulation of gm. 相似文献