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51.
In an investigation of the sporicidal activity of the KMT reagent, a vapor phase study was performed using five kinds of carriers contaminated with Geobacillus stearothermophilus spores. When 25 ml of the KMT reagent was vaporized in a chamber (capacity; approximately 95 liters), the 2-step heating method (vaporization by a combination of low temperature and high temperature) showed the most effective sporicidal activity in comparison with the 1-step heating method (rapid vaporization). The 2-step heating method appeared to be related to the sporicidal activity of vaporized KMT reagent, i.e., ethanol and iodine, which vaporized mainly when heated at a low temperature such as 55 C, and acidic water, which vaporized mainly when heated at a high temperature such as 300 C. We proposed that the KMT reagent can be used as a new disinfectant not only in the liquid phase but also in the vapor phase in the same way as peracetic acid and hydrogen peroxide.  相似文献   
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Behavioral phenotypes of Disc1 missense mutations in mice   总被引:6,自引:0,他引:6  
To support the role of DISC1 in human psychiatric disorders, we identified and analyzed two independently derived ENU-induced mutations in Exon 2 of mouse Disc1. Mice with mutation Q31L showed depressive-like behavior with deficits in the forced swim test and other measures that were reversed by the antidepressant bupropion, but not by rolipram, a phosphodiesterase-4 (PDE4) inhibitor. In contrast, L100P mutant mice exhibited schizophrenic-like behavior, with profound deficits in prepulse inhibition and latent inhibition that were reversed by antipsychotic treatment. Both mutant DISC1 proteins exhibited reduced binding to the known DISC1 binding partner PDE4B. Q31L mutants had lower PDE4B activity, consistent with their resistance to rolipram, suggesting decreased PDE4 activity as a contributory factor in depression. This study demonstrates that Disc1 missense mutations in mice give rise to phenotypes related to depression and schizophrenia, thus supporting the role of DISC1 in major mental illness.  相似文献   
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When Acidithiobacillus ferrooxidans ATCC23270 cells, grown for many generations on sulfur were grown in sulfur medium with and without Fe(3+), the bacterium markedly increased not only in iron oxidase activity but also in Fe(2+)-producing sulfide:ferric ion oxidoreductase (SFORase) activity during the early log phase, and retained part of these activities during the late log phase. The activity of SFORase, which catalyzes the production of Fe(2+) from Fe(3+) and sulfur, of sulfur-grown cells was approximately 10-20 fold higher than that of iron-grown cells. aa(3) type cytochrome c oxidase, an important component of iron oxidase in A. ferrooxidans, was partially purified from sulfur-grown cells. A. ferrooxidans ATCC23270 cells grown for many generations on sulfur had the ability to grow on iron as rapidly as that did iron-grown cells. These results suggest that both iron oxidase and Fe(2+)-producing SFORase have a role in the energy generation of A. ferrooxidans ATCC23270 from sulfur.  相似文献   
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Bacterial cellulose (BC) nanofibers were acetylated to enhance the properties of optically transparent composites of acrylic resin reinforced with the nanofibers. A series of BC nanofibers acetylated from degree-of-substitution (DS) 0 to 1.76 were obtained. X-ray diffraction profiles indicated that acetylation proceeded from the surface to the core of BC nanofibers, and scanning electron microscopy images showed that the volume of nanofibers increases by the bulky acetyl group. Since acetylation decreased the refractive index of cellulose, regular transmittance of composites comprised of 63% BC nanofiber was improved, and deterioration at 580 nm because of fiber reinforcement was suppressed to only 3.4%. Acetylation of nanofibers changed their surface properties and reduced the moisture content of the composite to about one-third that of untreated composite, although excessive acetylation increased hygroscopicity. Furthermore, acetylation was found to reduce the coefficient of thermal expansion of a BC sheet from 3 x 10(-6) to below 1 x 10(-6) 1/K.  相似文献   
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Redox-active Langmuir-Blodgett (LB) films containing dihydrophytyl ferrocenoate (DFc) and beta-carotene (betaC) were fabricated by use of 6-O-dihydrophytylcellulose (DHPC) as a matrix. A mixture of DFc-DHPC formed a stable monolayer. Atomic force microscopy images revealed that the DFc molecules were dispersed uniformly throughout the surface in the ratio DFc:DHPC = 2:8 at 30 mN m-1. The DFc-DHPC monolayer was transferred successfully onto a substrate, yielding Y-type LB films. Cyclic voltammograms for the DFc-DHPC LB films on an indium tin oxide (ITO) electrode exhibited a well-defined surface wave. The voltammograms of the DFc-DHPC LB films exhibited 60-40% redox-active ferrocene moieties, whereas those of the DFc-DHPC-betaC LB films exhibited 90-70%. X-ray diffraction patterns indicated that the distance between layers was independent of betaC molecules incorporated into the LB films. Consequently, these results suggested that betaC can function as a molecular wire.  相似文献   
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Molecular Biology Reports - GABAergic system dysfunction has been implicated in the etiology of schizophrenia and of cognitive impairments in particular. Patients with treatment-resistant...  相似文献   
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Arabidopsis thaliana calmodulin binding protein 60g (CBP60g) contributes to production of salicylic acid (SA) in response to recognition of microbe‐associated molecular patterns (MAMPs) such as flg22, a fragment of bacterial flagellin. Calmodulin binding is required for the function of CBP60g in limiting growth of the bacterial pathogen Pseudomonas syringae pv. maculicola (Pma) ES4326 and activation of SA synthesis. Here, we describe a closely related protein, SARD1. Unlike CBP60g, SARD1 does not bind calmodulin. Growth of Pma ES4326 is enhanced in sard1 mutants. In cbp60g sard1 double mutants, growth of Pma ES4326 is greatly enhanced, and SA levels and expression of PR‐1 and SID2 are dramatically reduced. Expression profiling placed the CBP60g/SARD1 node between the PAD4/EDS1 and SA nodes in the defense signaling network, and indicated that CBP60g and SARD1 affect defense responses in addition to SA production. A DNA motif bound by CBP60g and SARD1, GAAATTT, was significantly over‐represented in promoters of CBP60g/SARD1‐dependent genes, suggesting that expression of these genes is modulated by CBP60g/SARD1 binding. Gene expression patterns showed a stronger effect of cbp60g mutations soon after activation of a defense response, and a stronger effect of sard1 mutations at later times. The results are consistent with a model in which CBP60g and SARD1 comprise a partially redundant protein pair that is required for activation of SA production as well as other defense responses, with CBP60g playing a more important role early during the defense response, and SARD1 to playing a more important role later.  相似文献   
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