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31.
Matsuo T Yamaguchi S Mitsui S Emi A Shimoda F Okamura H 《Science (New York, N.Y.)》2003,302(5643):255-259
Cell division in many mammalian tissues is associated with specific times of day, but just how the circadian clock controls this timing has not been clear. Here, we show in the regenerating liver (of mice) that the circadian clock controls the expression of cell cycle-related genes that in turn modulate the expression of active Cyclin B1-Cdc2 kinase, a key regulator of mitosis. Among these genes, expression of wee1 was directly regulated by the molecular components of the circadian clockwork. In contrast, the circadian clockwork oscillated independently of the cell cycle in single cells. Thus, the intracellular circadian clockwork can control the cell-division cycle directly and unidirectionally in proliferating cells. 相似文献
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Carnosol is one of the main antioxidants in sage and rosemary. Although carnosol quinone is the antioxidation product of carnosol and has a very weak antioxidant activity, its treatment in water-containing solvent restored its strong antioxidant activity. HPLC analysis of the water-stimulated recovery reaction of the antioxidant activity revealed that the strong activity was due to the reproduced carnosol. The analysis also showed that an almost equal amount of quinone derivatives of rosmanol (rosmanol quinone) was produced in the reaction along with the carnosol. The rosmanol was formed by the addition of 1 equiv of water and the following isomerization from carnosol quinone in the water-containing solvent. The formed rosmanol was also found to be oxidized by the remaining carnosol quinone to produce rosmanol quinone. At the same time, carnosol quinone was reduced to afford carnosol. This redox phenomenon is an important part of the mechanism for the recovery of the antioxidant activity from carnosol quinone under the water-containing conditions. 相似文献
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35.
Suppressive effect of potassium silicate on powdery mildew of strawberry in hydroponics 总被引:1,自引:0,他引:1
Takeshi?KantoEmail author Akihiro?Miyoshi Takuya?Ogawa Kazumasa?Maekawa Masataka?Aino 《Journal of General Plant Pathology》2004,70(4):207-211
From 1996 to 1997, potassium silicate (SiO2) was tested at 0, 25, 50, and 100mgl–1 in hydroponics to control powdery mildew. Other elements were added in the usual amounts, and the strawberries were cultivated hydroponically in a greenhouse for 4 months (from October to January). The powdery mildew spread in the control plot, but little mildew developed in the plot with 25mgl–1 silicate, and none in plots with more than 50mgl–1 silicate. The suppressive effect lasted for about 4 months on fruits and even longer on leaves. On analysis of mineral content in the leaves, only the silicate content differed markedly between the control and treated plants. Nitrogen, phosphate, potassium, and calcium contents did not differ greatly. The maximum silicate content was about 24 times that of the control, and disease severity decreased significantly when the content was more than 1.5% in the leaves. The hardness of the strawberry leaves, measured by a creep meter, was increased by the silicate treatment. 相似文献
36.
Comparison of virulence of various hantaviruses related to hemorrhagic fever with renal syndrome in newborn mouse model 总被引:1,自引:0,他引:1
Lokugamage K Kariwa H Lokugamage N Iwasa M Hagiya T Araki K Tachi A Mizutani T Yoshimatsu K Arikawa J Iwasaki T Takashima I 《The Japanese journal of veterinary research》2004,51(3-4):143-149
The virulence of hantaviruses that are antigenically related but have different genetic characteristics from the prototype of hantavirus, Hantaan (HTN) virus, was examined in newborn mice. The H5 and B78 strains of the Amur (AMR) genotype, the Bao14 strain of the Far East (FE) genotype, and the 76-118 strain of HTN virus were inoculated subcutaneously (1focus-forming unit; FFU) into newborn mice. All of the AMR and FE genotype viruses inoculated mice were died by 16 days post-infection (dpi) and 21 dpi, respectively, while 50% of the HTN virus inoculated mice survived until 30 dpi. The AMR and FE genotype viruses inoculated mice had high viral titers in the lung (1.3x10(6) to 1.3x10(8) FFU/gram [g] tissue) , brain (2.1x10(7) to 1.2x10(9) FFU/g tissue), and kidney(2.5x10(5) to 1.6x10(7) FFU/g tissue), and showed a detectable level of antibodies (titers 1:16-1:32) at 14 dpi. In contrast, the HTN virus infected mice had viruses only in the lungs at low titers (1.1-5.3x10(5) FFU/g tissue). Observations of body-weight changes revealed that the AMR and FE genotype viruses inoculated mice had lower growth rates than the HTN virus inoculated mice. These data suggest that the AMR and FE genotype viruses are more virulent than the HTN virus in newborn mice. 相似文献
37.
Genetic and phylogenetic analysis of glycoprotein of rabies virus isolated from several species in Brazil 总被引:10,自引:0,他引:10
Sato G Itou T Shoji Y Miura Y Mikami T Ito M Kurane I Samara SI Carvalho AA Nociti DP Ito FH Sakai T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(7):747-753
Genetic and phylogenetic analyses of the region containing the glycoprotein (G) gene, which is related to pathogenicity and antigenicity, and the G-L intergenic region were carried out in 14 Brazilian rabies virus isolates. The isolates were classified as dog-related rabies virus (DRRV) or vampire bat-related rabies virus (VRRV), by nucleoprotein (N) analysis. The nucleotide and amino acid (AA) homologies of the area containing the G protein gene and G-L intergenic region were generally lower than those of the ectodomain. In both regions, nucleotide and deduced AA homologies were lower among VRRVs than among DRRVs. There were AA differences between DRRV and VRRV at 3 antigenic sites and epitopes (IIa, WB+ and III), suggesting that DRRV and VRRV can be distinguished by differences of antigenicity. In a comparison of phylogenetic trees between the ectodomain and the area containing the G protein gene and G-L intergenic region, the branching patterns of the chiropteran and carnivoran rabies virus groups differed, whereas there were clear similarities in patterns within the DRRV and VRRV groups. Additionally, the VRRV isolates were more closely related to chiropteran strains isolated from Latin America than to Brazilian DRRV. These results indicate that Brazilian rabies virus isolates can be classified as DRRV or VRRV by analysis of the G gene and the G-L intergenic region, as well as by N gene analysis. 相似文献
38.
PKA implicated in the phosphorylation of Cx43 induced by stimulation with FSH in rat granulosa cells 总被引:3,自引:0,他引:3
Yogo K Ogawa T Akiyama M Ishida-Kitagawa N Sasada H Sato E Takeya T 《The Journal of reproduction and development》2006,52(3):321-328
Connexin 43 (Cx43)-mediated gap junctional communication in granulosa cells is crucial for germ line development and postnatal folliculogenesis. We previously showed that follicle-stimulating hormone (FSH) promoted phosphorylation of Cx43 in rat primary granulosa cells. We further identified Ser365, Ser368, Ser369, and Ser373 in the carboxy-terminal tail as the major sites of phosphorylation by FSH, and found that the phosphorylation of these residues was essential for channel activity. In this study, we investigated the protein kinase(s) responsible for FSH-induced phosphorylation. H89, a cyclic AMP-dependent protein kinase (PKA) inhibitor, inhibited FSH-induced phosphorylation both in vivo and in vitro, whereas PD98059, a mitogen-activated protein kinase kinase (MEK) inhibitor, had little effect on the phosphorylation level. Ca2+-dependent protein kinase (PKC) appeared to negatively regulate phosphorylation. Phosphopeptide mapping with or without H89 treatment indicated that PKA could be responsible for phosphorylation of the four serine residues. In addition, the purified catalytic subunit of PKA could phosphorylate the recombinant C-terminal region of Cx43, but not the variant in which all four serine residues were substituted with alanine. These results suggest that FSH positively regulates Cx43-mediated channel formation and activity through phosphorylation of specific sites by PKA. 相似文献
39.
Kyoko Sugawara Misako Himeno Takuya Keima Yugo Kitazawa Kensaku Maejima Kenro Oshima Shigetou Namba 《Journal of General Plant Pathology》2012,78(6):389-397
Phytoplasmas are plant pathogenic bacteria that infect more than 700 plant species. Because phytoplasma-resistant cultivars are not available for the vast majority of crops, the most common practice to prevent phytoplasma diseases is to remove infected plants. Therefore, developing a rapid, accurate diagnostic method to detect a phytoplasma infection is important. Here, we developed a phytoplasma detection assay based on loop-mediated isothermal amplification (LAMP) by targeting the groEL gene and 16S rDNA. We designed 19 primer sets for the LAMP assay and evaluated their amplification efficiency, sensitivity, and spectra to select the most suitable primer sets to detect Candidatus Phytoplasma asteris. As a result, DNA was efficiently amplified by one of the primer sets targeting the groEL gene, and LAMP assay sensitivity with this primer set was 10-fold higher than that of the polymerase chain reaction. Moreover, the groEL gene was successfully amplified from several strains of Ca. Phytoplasma asteris by this primer set, indicating that the groEL gene can be used as a LAMP assay target gene for a broad range of phytoplasma strains. Additionally, a simple DNA extraction method that omits the homogenizing and phenol extraction steps was combined with the LAMP assay to develop a simple, rapid, and convenient diagnostic method for detecting phytoplasma. 相似文献
40.
Objective-To evaluate effects of extracellular lactate on viability, shape change, lactate metabolism, and reactive oxygen species (ROS) production in equine polymorphonuclear leukocytes (PMNs). Sample-PMNs isolated from equine venous blood samples. Procedures-PMNs were incubated with 0 to 300mM lactate for 30 minutes before each experiment. Viability was assessed via trypan blue exclusion. Shape change was assessed via flow cytometry and light microscopy. Relative quantification of monocarboxylic acid transporter and lactate dehydrogenase lactate dehydrogenase (LDH) isotype mRNAs was performed with a real-time PCR assay. Effects of lactate at a pH of 7.4 to 6.0 on ROS production in response to phorbol 12-myristate 13-acetate, opsonized zymosan, or N-formyl-methionyl-leucyl-phenylalanine was assessed by luminol-dependent chemiluminescence. Results-Lactate had no effect on viability of PMNs but did alter their size and density. Monocarboxylic acid transporter 1 and lactate dehydrogenase B mRNA values were not altered. Monocarboxylic acid transporter 4 and lactate dehydrogenase A mRNA values were significantly decreased. Lactate incubation of cells significantly decreased PMN-derived luminol-dependent chemiluminescence and induced different sensitivities to stimulants (phorbol 12-myristate 13-acetate, opsonized zymosan, and N-formyl-methionyl-leucyl-phenylalanine). The response ratio to N-formyl-methionyl-leucyl-phenylalanine revealed that PMNs were primed by incubation with up to 50mM lactate, significantly increasing the production of ROS. Incubation with lactate and acidic pH caused a synergistic effect on ROS production. Conclusions and Clinical Relevance-Extracellular lactate potentially has a direct effect on the capacity to produce ROS by equine PMNs, which may be associated with alterations in innate immune functions within a short period after high-intensity exercise. 相似文献