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151.
152.
Ai Takeda Mika Yasuda Ken Tabuchi Keiko Oku Wataru Sugeno Takayuki Mitsunaga Tetsuya Yasuda Tomonari Watanabe 《Applied Entomology and Zoology》2014,49(1):139-147
Evaluation of the landscape-level movement of Stenotus rubrovittatus (Matsumura), a major rice pest in Japan, is essential for establishing management strategies. We assessed the immigration timing and the average dispersal distance from a bank slope covered with Italian ryegrass Lolium multiflorum Lam. to paddy fields by periodic sampling in two regions in Chiba Prefecture. The immigrant densities in paddy fields increased exponentially as they approached the bank slope as a large-scale habitat of the insect. The relationship between immigrant density and distance from the source habitat fit an empirical model and theoretical model well. The theoretical model estimated the average dispersal distance during immigration: that of females was 72.0 and 92.1 m and that of males was 122.0 and 112.9 m in the respective regions. In addition, the average dispersal distance of males increased 7 days or later after the rice heading date despite the steady dispersal distance of females. 相似文献
153.
The present study describes the effect of salinity on the triterpenoid content of the salt secretor mangrove Avicennia marina and the non-secretor Rhizophora stylosa. Mangrove seedlings were grown for eight months in 0%, 0.5%, 1.5%, 2.0% and 3.0% salt concentration. The growth of both species was increased by salt with maximal stimulation at 1.5%, and this elevation appeared to be attenuated by increasing the salt concentration above 1.5%. The triterpenoid compositions of three types of chemical structures, lupane (lupeol, lupenone), oleanane (β-amyrin, taraxerol, germanicol), and ursane (α-amyrin), were studied. In addition, the phytosterol components campesterol, stigmasterol and β-sitosterol were analyzed. The total triterpenoid contents in the roots and leaves of A. marina for the 0% group were 87.0 and 66.2 μg g−1, respectively, and increased significantly to 173.1 and 142.6 μg g−1 with 3% salinity. The higher salinity also significantly increased the total concentration of phytosterols in the leaves and roots of this species. A similar increase in the concentration of both triterpenoids and phytosterols was observed in the roots and leaves of R. stylosa with increasing salt concentration. Thus, the triterpenoid concentration was increased by salinity in the roots and leaves of both A. marina and R. stylosa irrespective of their differences in salt management by salt excretion or by a non-excretion mechanism. Comparison of the triterpenoid concentration in four species of growing mangrove seedlings revealed a correlation between the total triterpenoid content and the salt tolerance based on the habitat zonation on Iriomote Island. A. marina thrives closest to sea and had the highest content of triterpenoids (173.1 μg g−1 in 3% salt group). Therefore, it is likely that the triterpenoid content play an important role in mangrove plants for protection from salinity in both salt-secretors and non-secretors. 相似文献
154.
A Gram-negative, strictly aerobic, reddish-pink pigmented, non-motile, rod-shaped strain designated N5DB8-4T, was isolated from an orange-striped sea anemone Diadumene lineata by a differential growth screening method. Phylogenetic analyses based on the 16S rRNA gene sequence revealed that the novel
isolate was affiliated with the family Flammeovirgaceae of the phylum Bacteroidetes and that it showed highest sequence similarity (89.1%) to Porifericola rhodea N5EA6-3A2BT. The strain could be differentiated phenotypically from recognized members of the family Flammeovirgaceae. The G+C content of the DNA is 52.6 mol%, the major respiratory quinone is menaquinone 7 (MK-7) and iso-C15:0, C16:1ω5c and
iso-C15:1 G (the double-bond position indicated by capital letter is unknown) were the major fatty acids. From the distinct
phylogenetic position and combination of genotypic and phenotypic characteristics, the strain represents a novel taxon for
which the name Tunicatimonas pelagia gen. nov., sp. nov. is proposed. The type strain of Tunicatimonas pelagia is N5DB8-4T (=KCTC 23473T = NBRC 107804T). 相似文献
155.
Liang XF Oku H Ogata HY 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2002,131(2):335-342
The effects of feeding condition and dietary lipid level on lipoprotein lipase (LPL) gene expression in the liver and visceral adipose tissue of red sea bream Pagrus major were investigated by competitive polymerase chain reaction. Not only visceral adipose tissue but also liver of red sea bream showed substantial LPL gene expression. In the liver, starvation (at 48 h post-feeding) drastically stimulated LPL gene expression in the fish-fed low lipid diet, but had no effect in the fish fed high lipid diet. Dietary lipid level did not significantly affect the liver LPL mRNA level under fed condition (at 5 h post-feeding). In the visceral adipose tissue, LPL mRNA number per tissue weight was significantly higher in the fed condition than in the starved condition, irrespective of the dietary lipid levels. Dietary lipid levels did not affect the visceral adipose tissue LPL mRNA levels under fed or starved conditions. Our results demonstrate that both feeding conditions and dietary lipid levels alter the liver LPL mRNA levels, while only the feeding conditions but not dietary lipid levels cause changes in the visceral adipose LPL mRNA level. It was concluded that the liver and visceral adipose LPL gene expression of red sea bream seems to be regulated in a tissue-specific fashion by the nutritional state. 相似文献
156.
Asai T Suzuki Y Matsushita S Yonezawa S Yokota J Katanasaka Y Ishida T Dewa T Kiwada H Nango M Oku N 《Biochemical and biophysical research communications》2008,368(2):243-248
Argonaute2 (Ago2), a component protein of RNA-induced silencing complex, plays a central role in RNA interference. We focused on the involvement of Ago2 in angiogenesis. Human umbilical vein endothelial cells (HUVECs) stimulated with several growth factors such as vascular endothelial growth factor were used for angiogenesis assays. We applied polycation liposomes for transfection of small interfering RNA (siRNA) to determine the biological effects of siRNA for Ago2 (siAgo2) on HUVECs. The proliferation study indicated that siAgo2 significantly suppressed the growth of HUVECs compared with control siRNA. TUNEL staining showed a certain population of HUVECs treated with siAgo2 underwent apoptosis. Furthermore, the treatment with siAgo2 suppressed the tube formation of HUVECs and significantly reduced the length of the tubes. These present data demonstrate that siAgo2 inhibited indispensable events of angiogenesis in vitro. This is the first report suggesting that Ago2 is required for angiogenesis. 相似文献
157.
The mechanism of the abnormal increase in extracellular glutamate concentration in the hippocampus induced with 100 mM KCl in zinc deficiency is unknown. In the present study, the changes in glutamate release (exocytosis) and GLT-1, a glial glutamate transporter, expression were studied in young rats fed a zinc-deficient diet for 4 weeks. Exocytosis at mossy fiber boutons was enhanced as reported previously and GLT-1 protein was increased in the hippocampus. The enhanced exocytosis is thought to increase extracellular glutamate concentration. However, the basal concentration of extracellular glutamate in the hippocampus was not increased by zinc deficiency, suggesting that GLT-1 protein increased serves to maintain the basal concentration of extracellular glutamate. The enhanced exocytosis was attenuated in the presence of 100 μM ZnCl2, which attenuated the abnormal increase in extracellular glutamate induced with high K+ in zinc deficiency. The present study indicates that zinc attenuates abnormal glutamate release in zinc deficiency. The enhanced exocytosis was also attenuated in slices from zinc-deficient rats administered Yokukansan, a herbal medicine, in which the abnormal increase in extracellular glutamate induced with high K+ was attenuated. It is likely that Yokukansan is useful for prevention or cure of abnormal glutamate release. The enhanced exocytosis in zinc deficiency is a possible mechanism on abnormal increase in extracellular glutamate in the hippocampus induced with high K+. 相似文献
158.
In the Kanzawa spider mite, Tetranychus kanzawai, adult males locate pre-reproductive quiescent females and engage in precopulatory mate guarding. We found that re-reproductive
quiescent females preferred to be near veins, rather than other leaf parts, and moreover, adult males spent more time along
the vein than on other parts. Consequently, T. kanzawai males found more quiescent females along veins than those on other parts. However, the predatory mite Neoseiulus womersleyi also found more quiescent T. kanzawai females along veins than those on other parts. Moreover, N. womersleyi found more guarding males than solitary males of T. kanzawai. Thus, we experimentally examined the effects of predation risk on the mating behavior of T. kanzawai. The presence of N. womersleyi reduced T. kanzawai female preference for vein vicinity as a quiescent site. Although the predation risk of guarding T. kanzawai males was lower than that of solitary males after detection by predators, the presence of N. womersleyi also reduced the proportion of guarding T. kanzawai males. These results suggest that the possible benefits of preferring vein vicinity as quiescent sites by T. kanzawai females is outweighed by predation risk in the presence of predators, and that the risk of detection by predators would be
more important for T. kanzawai males than the risk of being preyed upon. 相似文献
159.
Malaria is one of the most debilitating and life threatening diseases in tropical regions of the world. Over 500 million clinical cases occur, and 2-3 million people die of the disease each year. Because Plasmodium lacks genuine glutathione peroxidase and catalase, the two major antioxidant enzymes in the eukaryotic cell, malaria parasites are likely to utilize members of the peroxiredoxin (Prx) family as the principal enzymes to reduce peroxides, which increase in the parasite cell due to metabolism and parasitism during parasite development. In addition to its function of protecting macromolecules from H(2)O(2), Prx has also been reported to regulate H(2)O(2) as second messenger in transmission of redox signals, which mediate cell proliferation, differentiation, and apoptosis. In the malaria parasite, several lines of experimental data have suggested that the parasite uses Prxs as multifunctional molecules to adapt themselves to asexual and sexual development. In this review, we summarize the accumulated knowledge on the Prx family with respect to their functions in mammalian cells and their possible function(s) in malaria parasites. 相似文献
160.
Hofmann rearrangement of Nalpha-Boc-L-Gln-OH mediated by a polymer-supported hypervalent iodine reagent poly[(4-diacetoxyiodo)styrene] (PSDIB) in water afforded Nalpha-Boc-L-alpha,gamma-diaminobutyric acid (Boc-Dab-OH, 1) in 87% yield. Nalpha-Z-derivative (Z-Dab-OH, 2) was prepared with PSDIB in 83% yield. Since the reaction of Nalpha-Fmoc-Gln-OH by this procedure did not proceed because of the insolubility of Fmoc-Gln-OH in aqueous media, we synthesized Fmoc-Dab(Boc)-OH (5) from 2 in 54% yield. Polymyxin B heptapeptide (PMBH) which contains four Dab residues was successfully synthesized in a solution-phase synthesis. 相似文献