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81.
M Kawamura Y Yonezawa Y Tanaka N Imagawa C Tomita M Matsuba 《Endocrinologia japonica》1985,32(1):17-19
The effect of acetylcholine (ACh) on corticoidogenesis in primary cultured bovine adrenocortical cells was examined. One hour exposure to 10(-3) M ACh resulted in a stimulative effect on corticoidogenesis in the freshly isolated cells, and the effect of ACh grew intense during primary culture and reached the maximum on day 2. ACh showed the effect at a higher concentration than 10(-6) M. Thus the primary 2-day cultured cells were used. The corticoidogenic effect of ACh was inhibited by atropine but not by hexamethonium. The effect of ACh was dose dependent, and the extracellular Ca++ was obligatory in inducing the effect. These results suggest that the corticoidogenic effect of ACh may be due to an increase in Ca++-influx via muscarinic receptor in adrenocortical cells. 相似文献
82.
Zen-ichiro Hamauzu Tetsuo Toyomasu Daizo Yonezawa 《Bioscience, biotechnology, and biochemistry》2013,77(12):2445-2450
Gliadin was fractionated into three fractions; ω-gliadin, Fraction III (γ-gliadin) and Fraction IV (α- and β-gliadin). The determination of the molecular weights (MW) of the three fractions was performed by both SDS-polyacrylamide gel electrophoresis (SDS–PAGE) and sedimentation equilibrium. In SDS–PAGE, ω-gliadin gave three bands (MW 50,000, 54,000 and 64,000), Fraction III two bands (MW 38,000 and 46,000) and Fraction IV two bands (MW 33,000 and 38,000), The sedimentation analysis showed that each fraction was fairly homogeneous relative to molecular weight. The molecular weights obtained by sedimentation were 28,000 for Fraction III and 27,000 for both Fraction IV and ω-gliadin. The disagreement in molecular weight between sedimentation and gel electrophoresis was discussed. 相似文献
83.
Liu et al. reported the cultivation and DNA sequencing of 69 fungal isolates (Ascomycota and Basidiomycota) from ancient subseafloor sediments, suggesting that they represent living fungal populations that have persisted for over 20 million years. Because these findings could bring about a paradigm shift in our understanding of the spatial breadth of the deep subsurface biosphere as well as the longevity of ancient DNA, it is extremely important to verify that their samples represent pure ancient fungi from 20 million years ago without contamination by modern species. For this purpose, we estimated the divergence times of Dikarya (Ascomycota + Basidiomycota) and Mucoromycota fungi assuming that the fungal isolates were actually sampled from 20 Ma (mega-annum) sediments and evaluated the validity of the sample ages. Using this approach, we estimate that the age of the last common ancestor of Dikarya and Mucoromycota fungi greatly exceeds the age of the Earth. Our finding emphasizes the importance of using reliable approaches to confirm the dating of ancient samples. 相似文献
84.
The values of many plant traits are often different even within a species as a result of local adaptation. Here, we studied how multiple climate variables influence trait values in Arabidopsis thaliana grown under common conditions. We examined 9 climate variables and 29 traits related to vegetative growth rate in 44 global A. thaliana accessions grown at ambient or elevated CO2 concentration ([CO2]) and applied a multiple regression analysis. We found that genetic variations in the traits related to growth rates were associated with various climate variables. At ambient [CO2], plant size was positively correlated with precipitation in the original habitat. This may be a result of larger biomass investment in roots at the initial stage in plants adapting to a lower precipitation. Stomatal conductance and photosynthetic nitrogen use efficiency were negatively correlated with vapor pressure deficit, probably as a result of the trade-off between photosynthetic water- and nitrogen-use efficiency. These results suggest that precipitation and air humidity influence belowground and aboveground traits, respectively. Elevated [CO2] altered climate dependences in some of the studied traits. The CO2 response of relative growth rate was negatively correlated with altitude, indicating that plants inhabiting a higher altitude have less plasticity to changing [CO2]. These results are useful not only for understanding evolutionary process but also to predict the plant species that are favored under future global change. 相似文献
85.
Manabu Fukui Jungin Suh Yoshitaka Yonezawa Yoshikuni Urushigawa 《Ecological Research》1997,12(2):201-209
To clarify the anaerobic microbial interactions in the process of carbon mineralization in marine eutrophic environments,
the microbial sulfate reduction and methane production rates were examined in coastal marine sediments of Ise Bay, Japan,
in autumn 1990. Sulfate reduction rates (51–210 nmol ml−1 day−1 at 24°C) were much higher than the methane production ones (<1.78 nmol ml−1 day−1) in the surface sediments (top 2 cm) at the six stations surveyed (water depth: 10.7–23.3 m). Substrates for sulfate-reducing
bacteria (SRB) were estimated after the addition of a specific inhibitor for SRB (20 mmol l−1 molybdate) into the sediment slurry, from the substrate accumulation rates. In the presence of the inhibitor, sulfate reduction
was completely stopped and volatile fatty acids (mainly acetate) were accumulated, although hydrogen was not. Methane production
occurred markedly accompanied by consumption of the accumulated acetate from the third day after the addition of molybdate.
The maximum rate of methane production was 1.2–1.9 μmol ml−1 day−1, which was similar to those in highly polluted freshwater sediments such as the Tama River, Tokyo, Japan. These results show
that acetate is a common major substrate for sulfate reduction and methane production, and SRB competitively inhibit potential
acetoclastic methanogenesis in coastal sediments. Methanogens may potentially inhabit the sediments at low levels of population
density and activity. 相似文献
86.
87.
T-Tropic Human Immunodeficiency Virus Type 1 (HIV-1)-Derived V3 Loop Peptides Directly Bind to CXCR-4 and Inhibit T-Tropic HIV-1 Infection 总被引:3,自引:0,他引:3
88.
In order to clarify the transmission process of human immunodeficiency virus type 1 (HIV-1) through the epithelial cell barrier, HeLa cells susceptible and non-susceptible to HIV-1 were cloned and designated as P6 HeLa and N7 HeLa cells, respectively. P6 HeLa cells could be infected with the LAI strain of HIV-1 and mediated HIV-1 transcytosis. In contrast, N7 HeLa cells exhibited neither HIV-1 infection nor transcytosis. CD4 and galactosylceramide as the receptors for HIV-1 were not detected on P6 HeLa cells, although an anti-CD4 monoclonal antibody (mAb) blocked HIV-1 infection. Since HIV-1-infected P6 HeLa cells exhibited no fusion and survived, we speculated that the P6 HeLa cells expressed molecules other than CD4 which facilitated HIV-1 infection. Two mAbs (A-14 ITK and C57 a9-9) which inhibited the HIV-1 infection of P6 HeLa cells were generated. Each mAb recognized distinct molecule(s) as shown by Western blotting. Transcytosis by the P6 HeLa cells was inhibited by C57 a9-9 but not by A-14 ITK or anti-CD4 mAb. Both infection and transcytosis may be responsible for HIV-1 transmission through epithelial cells in a complex manner. Although infection and transcytosis occurred via different mechanisms, the molecule(s) recognized by C57 a9-9 mAb may be associated with both processes. 相似文献
89.
Proliferation of functional human natural killer cells with anti‐HIV‐1 activity in NOD/SCID/Jak3null mice 下载免费PDF全文
Shinichiro Hattori Kouki Matsuda Ryusho Kariya Seiji Okada 《Microbiology and immunology》2016,60(2):106-113
Natural killer cells, a critical component of the innate immune system, eradicate both virus‐infected cells and tumor cells through cytotoxicity and secretion of cytokines. Human NK cell research has largely been based on in vitro studies because of the lack of appropriate animal models. In this study, a selective proliferation model of functional human NK cells was established in NOD/SCID/Jak3null (NOJ) mice transplanted with peripheral blood mononuclear cells (PBMC) and K562 cells. The antiviral effects of NK cells were evaluated by challenging this mouse model with HIV‐1. The percentage of intracellular p24+ T cells and the amount of plasma p24 was decreased compared with NOJ mice transplanted with PBMC. Our findings indicate that NK cells have an anti‐HIV‐1 effect through direct cytotoxicity against HIV‐1‐infected cells. These mice provide an important model for evaluating human NK function against human infectious diseases such as HIV‐1 and malignancies. 相似文献
90.
Terasaki N Yamamoto N Tamada K Hattori M Hiraga T Tohri A Sato I Iwai M Iwai M Taguchi S Enami I Inoue Y Yamanoi Y Yonezawa T Mizuno K Murata M Nishihara H Yoneyama S Minakata M Ohmori T Sakai M Fujii M 《Biochimica et biophysica acta》2007,1767(6):653-659
We report on the first successful output of electrons directly from photosystem I (PSI) of thermophilic cyanobacteria to the gate of a field-effect transistor (FET) by bypassing electron flow via a newly designed molecular wire, i.e., artificial vitamin K(1), and a gold nanoparticle; in short, this newly manufactured photosensor employs a bio-functional unit as the core of the device. Photo-electrons generated by the irradiation of molecular complexes composed of reconstituted PSI on the gate were found to control the FET. This PSI-bio-photosensor can be used to interpret gradation in images. This PSI-FET system is moreover sufficiently stable for use exceeding a period of 1 year. 相似文献