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91.
Calcium releases of non-excitable cells are generally a combination of oscillatory and non-oscillatory patterns, and factors affecting the calcium dynamics are still to be determined. Here we report the influence of cell density on calcium increase patterns of clonal cell lines. The majority of HeLa cells seeded at 1.5 x 104/cm2 showed calcium oscillations in response to histamine and ATP, whereas cells seeded at 0.5 x 104/cm2 largely showed transient and sustained calcium increases. Cell density also affected the response of HEK293 cells to ATP in a similar manner. High cell density increased the basal activity of the mitogen-activated protein (MAP) kinase and calcium store content, and both calcium oscillation and calcium store content were down-regulated by a MAP kinase inhibitor, U0126. Thus, MAP kinase-mediated regulation of calcium store likely underlie the effect of cell density on calcium oscillation. Calcium increase patterns of HeLa cells were conserved at any histamine concentrations tested, whereas the overexpression of histamine H1 receptor, which robustly increased histamine-induced inositol phospholipid hydrolysis, converted calcium oscillations to sustained calcium increases only at high histamine concentrations. Thus, the consequence of modulating inositol phospholipid metabolism was distinct from that of changing cell density, suggesting the effect of cell density is not attributed to inositol phospholipid metabolism. Collectively, our results propose that calcium increase patterns of non-excitable cells reflect calcium store, which is regulated by the basal MAP kinase activity under the influence of cell density. 相似文献
92.
Masaya Ito Kate H. Bentley Yuki Oe Shun Nakajima Hiroko Fujisato Noriko Kato Mitsuhiro Miyamae Ayako Kanie Masaru Horikoshi David H. Barlow 《PloS one》2015,10(4)
Background
The Overall Depression Severity and Impairment Scale (ODSIS) is a brief, five-item measure for assessing the frequency and intensity of depressive symptoms, as well as functional impairments in pleasurable activities, work or school, and interpersonal relationships due to depression. Although this scale is expected to be useful in various psychiatric and mental health settings, the reliability, validity, and interpretability have not yet been fully examined. This study was designed to examine the reliability, factorial, convergent, and discriminant validity of a Japanese version of the ODSIS, as well as its ability to distinguish between individuals with and without a major depressive disorder diagnosis.Methods
From a pool of registrants at an internet survey company, 2830 non-clinical and clinical participants were selected randomly (619 with major depressive disorder, 619 with panic disorder, 576 with social anxiety disorder, 645 with obsessive–compulsive disorder, and 371 non-clinical panelists). Participants were asked to respond to the ODSIS and conventional measures of depression, functional impairment, anxiety, neuroticism, satisfaction with life, and emotion regulation.Results
Exploratory and confirmatory factor analysis of three split subsamples indicated the unidimensional factor structure of ODSIS. Multi-group confirmatory factor analysis showed invariance of factor loadings between non-clinical and clinical subsamples. The ODSIS also showed excellent internal consistency and test–retest intraclass correlation coefficients. Convergence and discriminance of the ODSIS with various measures were in line with our expectations. Receiver operating characteristic curve analyses showed that the ODSIS was able to detect a major depressive syndrome accurately.Conclusions
This study supports the reliability and validity of ODSIS in a non-western population, which can be interpreted as demonstrating cross-cultural validity. 相似文献93.
94.
95.
Biological control in orchards strongly depends on winter survival of natural enemies, especially in temperate regions. Predacious
phytoseiid mites overwinter on trees or on the ground depending on the characteristics of the species. However, the overwintering
ecology of phytoseiid mites on the ground is less well known than that of those on trees. We investigated the usefulness of
artificial overwintering shelters as a tool for studying the overwintering ecology of phytoseiid mites on the ground. Four
kinds of artificial shelter (shading net, felt, cardboard, and urethane foam) were placed on the ground in an apple orchard
in Korea. Two dominant phytoseiid species, Neoseiulus makuwa (Ehara) and N. womersleyi (Schicha) (Acari: Phytoseiidae), overwintered in the artificial ground shelters, and numbers were highest in the urethane
foam among the four kinds of shelter, and next highest in the shading net. On the other hand, the numbers of phytoseiid mites
collected in the ground vegetation plus soil samples under the ground shelters were not significantly different among the
five shelter treatments, including the no-shelter control. Our results suggest that artificial overwintering shelters are
efficient tools for investigating overwintering ecology of phytoseiid mites on the ground, as well as on trees, in orchards.
Furthermore, the artificial shelters would be good sampling units because they are easily formed into identical sizes and
can be used almost anywhere in the field with less laborious work. We also discuss some implications about the effects of
sheltered structures on the ground on the populations of phytoseiid mites during winter. 相似文献
96.
A novel factor FLOURY ENDOSPERM2 is involved in regulation of rice grain size and starch quality 总被引:6,自引:0,他引:6
She KC Kusano H Koizumi K Yamakawa H Hakata M Imamura T Fukuda M Naito N Tsurumaki Y Yaeshima M Tsuge T Matsumoto K Kudoh M Itoh E Kikuchi S Kishimoto N Yazaki J Ando T Yano M Aoyama T Sasaki T Satoh H Shimada H 《The Plant cell》2010,22(10):3280-3294
Rice (Oryza sativa) endosperm accumulates a massive amount of storage starch and storage proteins during seed development. However, little is known about the regulatory system involved in the production of storage substances. The rice flo2 mutation resulted in reduced grain size and starch quality. Map-based cloning identified FLOURY ENDOSPERM2 (FLO2), a member of a novel gene family conserved in plants, as the gene responsible for the rice flo2 mutation. FLO2 harbors a tetratricopeptide repeat motif, considered to mediate a protein-protein interactions. FLO2 was abundantly expressed in developing seeds coincident with production of storage starch and protein, as well as in leaves, while abundant expression of its homologs was observed only in leaves. The flo2 mutation decreased expression of genes involved in production of storage starch and storage proteins in the endosperm. Differences between cultivars in their responsiveness of FLO2 expression during high-temperature stress indicated that FLO2 may be involved in heat tolerance during seed development. Overexpression of FLO2 enlarged the size of grains significantly. These results suggest that FLO2 plays a pivotal regulatory role in rice grain size and starch quality by affecting storage substance accumulation in the endosperm. 相似文献
97.
98.
Mitsuhiro Obara Wataru Tamura Takeshi Ebitani Masahiro Yano Tadashi Sato Tomoyuki Yamaya 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,121(3):535-547
Root system development is an important target for improving yield in cereal crops. Active root systems that can take up nutrients
more efficiently are essential for enhancing grain yield. In this study, we attempted to identify quantitative trait loci
(QTL) involved in root system development by measuring root length of rice seedlings grown in hydroponic culture. Reliable
growth conditions for estimating the root length were first established to renew nutrient solutions daily and supply NH4
+ as a single nitrogen source. Thirty-eight chromosome segment substitution lines derived from a cross between ‘Koshihikari’,
a japonica variety, and ‘Kasalath’, an indica variety, were used to detect QTL for seminal root length of seedlings grown in 5 or 500 μM NH4
+. Eight chromosomal regions were found to be involved in root elongation. Among them, the most effective QTL was detected
on a ‘Kasalath’ segment of SL-218, which was localized to the long-arm of chromosome 6. The ‘Kasalath’ allele at this QTL,
qRL6.1, greatly promoted root elongation under all NH4
+ concentrations tested. The genetic effect of this QTL was confirmed by analysis of the near-isogenic line (NIL) qRL6.1. The seminal root length of the NIL was 13.5–21.1% longer than that of ‘Koshihikari’ under different NH4
+ concentrations. Toward our goal of applying qRL6.1 in a molecular breeding program to enhance rice yield, a candidate genomic region of qRL6.1 was delimited within a 337 kb region in the ‘Nipponbare’ genome by means of progeny testing of F2 plants/F3 lines derived from a cross between SL-218 and ‘Koshihikari’. 相似文献
99.
Fusarium sp. BLB, which produces a strongly fibrinolytic enzyme, was isolated from plant leaf (Hibiscus). Fibrinolytic alkaline protease was purified from a culture filtrate of Fusarium sp. BLB by precipitation with (NH4)2SO4 and column chromatography with CM-Toyopearl 650M and Superdex 75. The purified enzyme was homogeneous on sodium dodecyl sulfate
polyacrylamide gel electrophoresis (SDS-PAGE). The molecular weight was 27,000 by SDS-PAGE. Maximum activity of protease was
observed at pH 9.5 and 50°C. Purified protease was active between pH 2.5 and 11.5 and was found to be stable up to 50°C. The
enzyme derived from Fusarium sp. BLB is useful for thrombolytic therapy because this enzyme showed pH resistance. The activity was inhibited by diisopropylfluorophosphate
and phenylmethylsulfonyl fluoride. The N-terminal amino acid sequence of the enzyme showed a similarity to those of proteases
from Fusarium sp., Streptomyces griseus, Bos taurus bovine, Katsuwo pelamis digestive tract, and Lumbricus rubellus. 相似文献
100.
RNA motifs comprising nucleotides that interact through non-Watson-Crick base pairing play critical roles in RNA functions, often by serving as the sites for RNA-RNA, RNA-protein, or RNA small ligand interactions. The structures of viral and viroid RNA motifs are studied commonly by in vitro, computational, and mutagenesis approaches. Demonstration of the in vivo existence of a motif will help establish its biological significance and promote mechanistic studies on its functions. By using UV cross-linking and primer extension, we have obtained direct evidence for the in vivo existence of the loop E motif of Potato spindle tuber viroid. We present our findings and discuss their biological implications. 相似文献