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1.
ABSTRACT: Glucose has been implicated in functioning as a form of carbon translocated from symbiont zooxanthellae to the host coral cell. The present paper describes the lipid biosynthesis from [14 C]-glucose in the coral tissue. To study the incorporation of [14 C]-glucose into lipids, the branch tips of the coral Montipora digitata were incubated with [14 C]-glucose or another radiolabeled substrates. The lipid biosynthesis from [14 C]-glucose was dependent on light, and was decreased by dark conditions or by photosystem II inhibitor, 3-(3,4-dichlorophenyl)-1,1-dimethylurea. Of the lipid classes, the light dependency was more pronounced with the biosynthesis of triacylglycerols (TG) and wax compared with phospholipids. Examination of [14 C]-label distribution in the glycerolipids suggested that [14 C]-glucose supplied mainly the fatty acid moiety of newly synthesized TG, while [14 C]-glucose provided evenly the fatty acid moiety and the glycerol skeleton of phospholipids. The comparison of [14 C]-labeling of lipid from host coral tissue and symbiont zooxanthellae suggested that [14 C]-glucose entered the coral cell and was processed in parallel in the zooxanthellae and host cells. Furthermore, the coral cells used various [14 C]-labeled sugars for lipid synthesis with similar lipid labeling profile as was the case for glucose. The current study thus supports the view that the low-molecular-weight compound, sugars and amino acids, once translocated from zooxanthellae to host cell were metabolized toward lipogenesis as well as glycerol. 相似文献
2.
Takahito?KojimaEmail author Hirosuke?Ito Tomoyuki?Komada Toru?Taniuchi Tomonari?Akamatsu 《Fisheries Science》2005,71(1):95-100
ABSTRACT: Recently, the non-invasive auditory brainstem response (ABR) technique has been applied to the determination of hearing sensitivity in fish. The technique has some advantages over, and methodological differences from, the classical techniques. The auditory thresholds of common carp were measured by the ABR technique. The classical method was applied to measure cardiac response by electrocardiogram (ECG) after conditioning with electric shock. The most sensitive frequency obtained by ABR was 505 Hz, and by ECG, 1000 Hz. The shapes of the audiogram obtained by ABR and ECG were similar, though threshold levels in both audiograms differed from each other. Furthermore, audiograms obtained by using behavioral techniques were compared with those taken by the ABR and ECG techniques to assess the validity of the ABR technique for testing fish hearing sensitivity. The measured threshold levels increased in the order of behavioral, ABR, and ECG techniques, in the range below 1000 Hz. 相似文献
3.
Lipid distribution in branching coral Montipora digitata 总被引:1,自引:0,他引:1
Hirosuke OKU Hideyuki YAMASHIRO Kyoko ONAGA Hironori IWASAKI Kensaku TAKARA 《Fisheries Science》2002,68(3):517-522
>ABSTRACT: The lipid profile was studied along the branch length, from the top, middle to base portion, of coral Montipora digitata to gain more insight into the physiological significance of lipids in the coral energy budget. The lipids of M. digitata consisted of seven major lipid classes: polar lipid, sterol, free fatty acid, unknown lipids 1 and 2, triacylglycerol (TG), and wax ester. The concentration of storage lipids, TG, and wax ester showed a top–base gradient along the length, whereas the levels of free fatty acid and unknown lipids showed a base–top gradient. The proportions of polar lipid and sterol in the top portion of the branch were slightly higher than those in the base portion. This observation appeared to be compatible with the view that the increased energy expenditure for proliferation enhanced the mobilization of the storage fuel lipids of wax ester and TG rather than the structure lipids of polar lipids and sterols at the top portion of the branch. Compositions of fatty acid also showed a length-wise diversity. The top portion had a lower proportion of palmitic acid (16 : 0) in all lipid classes of fatty acid ester, suggesting that this fatty acid was preferentially mobilized at the top portion, probably for the growth of coral cells. 相似文献
4.
Lipid contents and compositions of the bleached Okinawan corals were analyzed for the first time. Bleached corals collected
at Sesoko Okinawa, Japan (26°38′N, 127°52′E), after the 1998 bleaching event showed decreased lipid content with a concomitant
decline of wax in the lipid composition. The reductionin the lipid content of corals showed diversity depending on their colony
morphology. On the whole, corals of massive morphology were relatively rich in lipid even after the bleaching event, and hence
lesser reduction in the lipid content compared with the cases for those of branching morphology. Furthermore, there was a
positive correlation between lipid content and zooxanthellae density in the bleached corals, suggesting again the importance
of symbiont for the supply of lipid to the host cells, and hence for the survival of the bleaching event. 相似文献
5.
Kobori M Nakayama H Fukushima K Ohnishi-Kameyama M Ono H Fukushima T Akimoto Y Masumoto S Yukizaki C Hoshi Y Deguchi T Yoshida M 《Journal of agricultural and food chemistry》2008,56(11):4004-4011
Bitter gourd ( Momordica charantia L.) is a popular tropical vegetable in Asian countries. Previously it was shown that bitter gourd placenta extract suppressed lipopolysaccharide (LPS)-induced TNFalpha production in RAW 264.7 macrophage-like cells. Here it is shown that the butanol-soluble fraction of bitter gourd placenta extract strongly suppresses LPS-induced TNFalpha production in RAW 264.7 cells. Gene expression analysis using a fibrous DNA microarray showed that the bitter gourd butanol fraction suppressed expression of various LPS-induced inflammatory genes, such as those for TNF, IL1alpha, IL1beta, G1p2, and Ccl5. The butanol fraction significantly suppressed NFkappaB DNA binding activity and phosphorylation of p38, JNK, and ERK MAPKs. Components in the active fraction from bitter gourd were identified as 1-alpha-linolenoyl-lysophosphatidylcholine (LPC), 2-alpha-linolenoyl-LPC, 1-lynoleoyl-LPC, and 2-linoleoyl-LPC. Purified 1-alpha-linolenoyl-LPC and 1-linoleoyl-LPC suppressed the LPS-induced TNFalpha production of RAW 264.7 cells at a concentration of 10 microg/mL. 相似文献
6.
Mami OIKAWA Shogo MATOBA Kimiko INOUE Satoshi KAMIMURA Michiko HIROSE Narumi OGONUKI Hirosuke SHIURA Michihiko SUGIMOTO Kuniya ABE Fumitoshi ISHINO Atsuo OGURA 《The Journal of reproduction and development》2013,59(3):231-237
In mice, one of the major epigenetic errors associated with somatic cell nuclear
transfer (SCNT) is ectopic expression of Xist during the preimplantation
period in both sexes. We found that this aberrant Xist expression could
be impeded by deletion of Xist from the putative active X chromosome in
donor cells. In male clones, it was also found that prior injection of
Xist-specific siRNA could significantly improve the postimplantation
development of cloned embryos as a result of a significant repression of
Xist at the morula stage. In this study, we examined whether the same
knockdown strategy could work as well in female SCNT-derived embryos. Embryos were
reconstructed with cumulus cell nuclei and injected with Xist-specific
siRNA at 6–7 h after oocyte activation. RNA FISH analysis revealed that siRNA treatment
successfully repressed Xist RNA at the morula stage, as shown by the
significant decrease in the number of cloud-type Xist signals in the
blastomere nuclei. However, blastomeres with different sizes (from “pinpoint” to “cloud”)
and numbers of Xist RNA signals remained within single embryos. After
implantation, the dysregulated Xist expression was normalized
autonomously, as in male clones, to a state of monoallelic expression in both embryonic
and extraembryonic tissues. However, at term there was no significant improvement in the
survival of the siRNA-injected cloned embryos. Thus, siRNA injection was largely effective
in repressing the Xist overexpression in female cloned embryos but failed
to rescue them, probably because of an inability to mimic consistent monoallelic
Xist expression in these embryos. This could only be achieved in female
embryos by applying a gene knockout strategy rather than an siRNA approach. 相似文献
7.
Masachika Hirano Nobushige Itaya Isao Ohno Yoshio Fujita Hirosuke Yoshioka 《Pest management science》1979,10(4):291-294
Thirteen pyrethroid-type esters of substituted 1(or 3)-hydroxymethylimidazolidine-2, 4-dione were synthesised and their knockdown activities against houseflies, mosquitoes and cockroaches were examined. Knockdown activities of 2,4-dioxo-1-prop-2-ynylimidazolidin-3-ylmethyl esters in oil solutions were higher than those of known knockdown pyrethroids; three of the compounds also possessed strong knockdown and flushing-out activities against cockroaches. 相似文献
8.
Tetsuya Akasaki Toshiro Saruwatari Hirosuke Tomonaga Soei Sato Yoshiro Watanabe 《Fisheries Science》2006,72(3):686-692
ABSTRACT: Quality control of imported fish products is a constant challenge for Customs officials. To help officials access the quality and integrity of imported fish products, and to enhance the effectiveness and accuracy of product screening, a method was developed to identify boiled and dried larval and juvenile sardines (Chirimen) at the genus level by direct sequencing using a partial sequence (606 bp) of mitochondrial 16S rDNA. A phylogenetic tree was constructed, based on nucleotide sequences of seven kinds of Chirimen imported from four countries with 16 standard samples belonging to the orders Clupeiformes and Salmoniformes. To identify the fish genera in imported Chirimen, bootstrap values and branch lengths of the phylogenetic tree as well as genetic distances were used. The data revealed that Chirimen imported from China and Korea contains species of the genus Engraulis . Regarding other imported Chirimen, the least that could be verified was that the sardine ingredients do not belong to regulated genera. 相似文献
9.
Nobuo Ohno Keimei Fujimoto Yoshitoshi Okuno Toshio Mizutani Masachika Hirano Nobushige Itaya Toshiko Honda Hirosuke Yoshioka 《Pest management science》1976,7(3):241-246
Although structure modifications of natural pyrethrin constituents have disclosed a variety of potent synthetic analogues, all known examples are cyclopropanecarboxylate esters, a grouping that appeared to be essential for insecticidal activity. Some new substituted 2-phenylalkanoates, whose biological activities are of a similar nature and potency to those of conventional pyrethroids, are now reported. 5-Benzyl-3-furylmethyl and 3-phenoxybenzyl 3-methyl-2-phenylbutyrates and their analogues are potent insecticides. Activity is increased on the introduction of appropriate groups into the 3 and/or 4-positions of the aryl ring and the (S)-2-phenylalkanoates are far more active than their (R)-enantiomorphs. Structure/activity relationships are compared with those for conventional pyrethroids. Some of the new series compare favourably with typical insecticides in tests against Musca domestica, Spodoptera litura and Plutella xylostella. 相似文献
10.
Tokio Obata Katsutoshi Fujii Haruo Yoshiya Kiyoshi Tsutsumiuchi Hirosuke Yoshioka 《Pest management science》1992,34(2):133-138
A new class of insecticides and acaricides containing N-(α-substituted phenoxybenzyl)-4-pyrimidinamines as core structure were synthesized and their insecticidal and acaricidal potencies assessed. Among these, both the N-(3 or 4-phenoxybenzyl)-4-pyrimidinamine showed remarkable activity against diamondback moth, Plutella xylostella L., brown rice planthopper, Nilaparvata lugens (Stal) and two-spotted spider mite, Tetranychus urticae Koch. The potency of the new pyrimidinamines was particularly increased when a methyl, ethyl, iso-propyl, or cyclopropyl group was introduced at the α-position of benzyl moiety and it was evident that a single (+) optical isomer is more active than its antipode. Structure-activity relationships are discussed. 相似文献