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71.
Seiji Hayashizaki Shinobu Hirai Yumi Ito Yoshiko Honda Yosefu Arime Ichiro Sora Haruo Okado Tohru Kodama Masahiko Takada 《PloS one》2013,8(10)
Dopamine regulates the psychomotor stimulant activities of amphetamine-like substances in the brain. The effects of dopamine are mediated through five known dopamine receptor subtypes in mammals. The functional relevance of D5 dopamine receptors in the central nervous system is not well understood. To determine the functional relevance of D5 dopamine receptors, we created D5 dopamine receptor-deficient mice and then used these mice to assess the roles of D5 dopamine receptors in the behavioral response to methamphetamine. Interestingly, D5 dopamine receptor-deficient mice displayed increased ambulation in response to methamphetamine. Furthermore, dopamine transporter threonine phosphorylation levels, which regulate amphetamine-induced dopamine release, were elevated in D5 dopamine receptor-deficient mice. The increase in methamphetamine-induced locomotor activity was eliminated by pretreatment with the dopamine transporter blocker GBR12909. Taken together, these results suggest that dopamine transporter activity and threonine phosphorylation levels are regulated by D5 dopamine receptors. 相似文献
72.
Manoeli Lupatini Afnan Khalil Ahmad Suleiman Rodrigo Josemar Seminoti Jacques Zaida Inês Antoniolli Eiko Eurya Kuramae Flávio Anastácio de Oliveira Camargo Luiz Fernando Würdig Roesch 《PloS one》2013,8(10)
The Pampa biome is considered one of the main hotspots of the world’s biodiversity and it is estimated that half of its original vegetation was removed and converted to agricultural land and tree plantations. Although an increasing amount of knowledge is being assembled regarding the response of soil bacterial communities to land use change, to the associated plant community and to soil properties, our understanding about how these interactions affect the microbial community from the Brazilian Pampa is still poor and incomplete. In this study, we hypothesized that the same soil type from the same geographic region but under distinct land use present dissimilar soil bacterial communities. To test this hypothesis, we assessed the soil bacterial communities from four land-uses within the same soil type by 454-pyrosequencing of 16S rRNA gene and by soil microbial activity analyzes. We found that the same soil type under different land uses harbor similar (but not equal) bacterial communities and the differences were controlled by many microbial taxa. No differences regarding diversity and richness between natural areas and areas under anthropogenic disturbance were detected. However, the measures of microbial activity did not converge with the 16S rRNA data supporting the idea that the coupling between functioning and composition of bacterial communities is not necessarily correlated. 相似文献
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Sergios A. Nicolaou Alan G. Fast Eiko Nakamaru-Ogiso Eleftherios T. Papoutsakis 《Applied and environmental microbiology》2013,79(23):7210-7219
Reactive oxygen species are generated by redox reactions and the Fenton reaction of H2O2 and iron that generates the hydroxyl radical that causes severe DNA, protein, and lipid damage. We screened Escherichia coli genomic libraries to identify a fragment, containing cueR, ybbJ, qmcA, ybbL, and ybbM, which enhanced resistance to H2O2 stress. We report that the ΔybbL and ΔybbM strains are more susceptible to H2O2 stress than the parent strain and that ybbL and ybbM overexpression overcomes H2O2 sensitivity. The ybbL and ybbM genes are predicted to code for an ATP-binding cassette metal transporter, and we demonstrate that YbbM is a membrane protein. We investigated various metals to identify iron as the likely substrate of this transporter. We propose the gene names fetA and fetB (for Fe transport) and the gene product names FetA and FetB. FetAB allows for increased resistance to oxidative stress in the presence of iron, revealing a role in iron homeostasis. We show that iron overload coupled with H2O2 stress is abrogated by fetA and fetB overexpression in the parent strain and in the Δfur strain, where iron uptake is deregulated. Furthermore, we utilized whole-cell electron paramagnetic resonance to show that intracellular iron levels in the Δfur strain are decreased by 37% by fetA and fetB overexpression. Combined, these findings show that fetA and fetB encode an iron exporter that has a role in enhancing resistance to H2O2-mediated oxidative stress and can minimize oxidative stress under conditions of iron overload and suggest that FetAB facilitates iron homeostasis to decrease oxidative stress. 相似文献
75.
Shogo Higaki Yutaka Kawakami Yoshiki Eto Etsuro Yamaha Masashi Nagano Seiji Katagiri Tatsuyuki Takada Yoshiyuki Takahashi 《Cryobiology》2013
The aim of this study was to examine the effects of partial removal of yolk and cryoprotectant mixtures on the viability of cryopreserved primordial germ cells (PGCs) and elucidated the differentiation ability of cryopreserved PGCs in zebrafish. First, dechorionated yolk-intact and yolk-depleted (partially yolk removed) embryos, PGCs of which were labeled with green fluorescence protein (GFP), were vitrified after serial exposures to pretreatment solution (PS) and vitrification solution (VS) that contained ethylene glycol (EG), dimethyl sulfoxide (Me2SO) or propylene glycol at 3 and 5 M, respectively. Although partial removal of yolk improved the viability of cryopreserved PGCs, numbers of PGCs with pseudopodial movement were limited (0–2.6 cells/embryo). Next, yolk-depleted embryos were cryopreserved using mixtures of two types of cryoprotectants. The maximum survival rate of PGCs (81%; 9.6 cells/embryo) was obtained from the yolk-depleted embryos vitrified using PS containing 2 M EG + 1 M Me2SO and VS containing 3 M EG + 2 M Me2SO and 56% (5.3 cells/embryo) of PGCs showed pseudopodial movement. Finally, PGCs recovered from yolk-depleted embryos (wild-type) that were vitrified under the optimum condition were transplanted individually into 236 sterilized recipient blastulae (recessive light-colored). Seven recipients matured and generated progeny with characteristics inherited from the PGC donor. In conclusion, the authors confirmed the beneficial effects of partial removal of yolk on the viability of cryopreserved PGCs and that the viability of the PGCs was improved by using PS and VS that contained two types of cryoprotectants, especially PS containing 2 M EG + 1 M Me2SO and VS containing 3 M EG + 2 M Me2SO, and that recovered PGCs retained ability to differentiate into functional gametes. 相似文献
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Eiko Matsumura Eiko Yamamoto Atsushi Numata Tatsu Kawano Takashi Shin Sawao Murao 《Bioscience, biotechnology, and biochemistry》2013,77(5):1355-1357
Esters selected from the combination of tricycloalkanecarboxylic acids and some representative pyrethroidal alcohols were prepared, and their insecticidal activities were measured by topical application on housefly, mosquito and German cockroach. Both the exo- and endo-isomers of 2,3-trimethylenenorbornane-2-carboxylic acid exhibited a high level of activity when esterified with m-phenoxymandelonitrile. Piperonyl butoxide showed a strong synergistic effect on some of the esters. Several structural resemblances were found among these active tricyclic acids and the chrysanthemummonocarboxylic acids, which were suggested to be related to insecticidal activity. 相似文献
79.
An alkalopsychrotrophic strain, Micrococcus sp. 207, inducibly and extracellularly produced amylase and pullulanase. The main hydrolysis product from amylose, with a crude enzyme preparation, was maltotetraose. The optimum temperature for activity of the amylase was 60°C and that for pullulanase 55°C. The activities at 0 to 30°C exhibited similar activation energy values. In an optimized production medium at pH 9.7, the highest yields of these enzymes were obtained after cell growth at 18°C for 4 days. At pH 8.5, the yields of amylase and pullulanase became maximum after 3 days cultivation. With more prolonged cultivation, the yield of amylase but not that of pullulanase activity decreased. These enzymes were not produced at temperatures above 30°C. Sucrose was not effective as an inducer, but it stimulated cell growth and enhanced the enzyme productivities with soluble starch. 相似文献
80.
Yoshiyasu Fujimura Masayuki Takada Hiroko Fujita Takashi Inoue 《Landscape and Ecological Engineering》2013,9(2):305-309
In recent decades, the extent of Sasa palmata-dominant communities has increased in Sarobetsu Mire in northern Hokkaido, Japan, replacing the original Sphagnum bog vegetation. However, this marked increase in distribution of Sasa in the mire has not been formally documented or investigated in detail. Using aerial photo-interpretation, the present study updated the distribution maps of Sasa communities, showing the changes that have occurred to these communities between 1977 and 2003. The results revealed that the extent of Sasa communities has increased by 15.8 % from 6.60 km2 in 1977 to 7.64 km2 in 2003. The most marked increase occurred on the ground associated with drainage channels, although the oldest channels were constructed more than half a century ago, suggesting that some responses to the drainage of peat bog ecosystems may take a considerable period of time before becoming particularly evident. 相似文献