排序方式: 共有21条查询结果,搜索用时 203 毫秒
1.
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
2.
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
3.
4.
Matsubayashi M Carreno RA Tani H Yoshiuchi R Kanai T Kimata I Uni S Furuya M Sasai K 《Veterinary parasitology》2011,176(2-3):270-274
Cystoisospora spp. from feces in dogs, cats, and raccoon dogs were isolated, sequenced at the small subunit ribosomal RNA gene locus and compared to other Cystoisospora spp. Cystoisospora oocysts from dogs and raccoon dogs were morphologically similar with those of C. ohioensis, and cat isolates were similar with those of C. felis. The sequences from dogs and raccoon dogs, and cats have a homology with C. ohioensis and C. felis, respectively. Phylogenetic analysis of the DNA sequences showed that the dog and raccoon dog isolates were nested in a clade with other Cystoisospora spp. including C. ohioensis, C. belli, and C. orlovi. The cat isolate formed a sister group with C. felis that was a separate clade from the dog and raccoon dog group. We report sequence variation in these Cystoisospora sequences and have identified raccoon dogs as another carnivore host for Cystoisospora spp. infecting dogs. 相似文献
5.
6.
Kanami Mori Takashi Ooi Masanori Hiraoka Naohiro Oka Hideyuki Hamada Mitsumasa Tamura Takenori Kusumi 《Marine drugs》2004,2(2):63-72
Three metabolites of fucoxanthin were isolated from a brown alga, Scytosiphon lomentaria, and the structure of a new compound was determined by NMR. The content of fucoxanthin, a biologically active carotenoid, in four edible brown algae, cultivated in deep seawater, was studied. 相似文献
7.
The abandonment of sites after clearcutting plantations is increasing rapidly in Japan. Although a few stand-level studies
have been conducted, a broad-scale study is needed to understand the general tendency of vegetation recovery and to obtain
information for the management of such extensively distributed abandoned clearcut sites. This study is a province-level study
that aims to interpret the patterns and factors in early-stage vegetation recovery at abandoned plantation clearcut sites.
We also discuss the potential indicators that may determine whether a certain site recovers towards evergreen broad-leaved
forest consisting of Castanopsis cuspidata and Quercus glauca or towards deciduous broad-leaved forest comprising Q. serrata and Q. acutissima. A cluster analysis revealed that five types of vegetation (evergreen trees, evergreen trees–deciduous pioneer shrubs, pioneer
species, deciduous trees, and deciduous shrubs) were observed from an early stage of succession. The first two vegetation
types were considered to recover successfully to the target vegetation of evergreen broad-leaved forest, but the remaining
three vegetation types did not show any tendency to recover to the target vegetations. According to the results of the detrended
correspondence analysis, a smaller size of the abandoned site with adjacent evergreen broad-leaved forest and a longer time
after clearcutting were identified as factors that enhance the invasion of evergreen tree species; these factors are also
useful to predict the future successional tendency. In conjunction with these factors, the existence of regeneration sources
(i.e., stumps) that allow sprouting appeared to be an important indicator for predicting the early-stage vegetation recovery. 相似文献
8.
Keiji OKADA Kazue YAJIMA Takamichi OHBA Tamako MIYAZAKI Takenori ORIHASHI Shigeru SATO Jun YASUDA 《Animal Science Journal》2010,81(1):89-93
Eight Holstein bull calves were divided into two groups; a non-treated control group and a famotidine treated group. Fresh milk was fed twice a day. The experiment was conducted between 7 and 14 days of age. During the experimental period the control group was injected with physiological saline, and the famotidine group was injected with famotidine, a histamine-H2-receptor blocker, into the jugular vein 30 minutes prior to each feeding. The control group showed maximum curd formation 2 h after feeding at both 7 and 14 days of age. Curd scores of 7-day-old and 14-day-old calves were significantly lower in the famotidine than in the control group at 2 and 4 h after feeding. Most fecal samples from the famotidine group exhibited an acidic smell. The famotidine group showed significantly lower values for both average weight gain and the rate of weight gain from 7 to 14 days of age. The inhibition of gastric acid secretion decreased curd formation in the abomasum as well as daily weight gain compared to non-treated control calves. This suggested that curd formation in the abomasum is important for the weight gain of newborn calves. 相似文献
9.
Arisa MUNETOMO Hirotaka ISHII Takenori MIYAMOTO Yasuo SAKUMA Yasuhiko KONDO 《The Journal of reproduction and development》2016,62(1):17-27
In the rat, induction of maternal behavior depends on the parity of the female. For example, nulliparous
(NP) females need longer exposure to pups than multiparous (MP) or lactating (L) females to exhibit similar
maternal behavior. In this study, we investigated the role of brain oxytocin in the approaching behavior of
these female rats. Olfactory preferences for pup odors were examined for 8 consecutive days. Each preference
test was followed by direct overnight exposure to pups. On the 8th day, MP and L, but not NP females showed
robust pup-odor preferences. After the behavioral test, half of the females were exposed to pups for 2 h,
whereas the other half were not. The females were then sacrificed to analyze brain oxytocin (OXT) and
vasopressin (AVP) activities by cFos immunohistochemistry and to quantify their receptor mRNA expression using
real-time PCR. In the paraventricular nucleus (PVN), the percentage of cFos-positive OXT neurons was
significantly larger in MP and L females than in NP females after pup exposure. No significant differences
were found in cFos expression in OXT neurons of the supraoptic nucleus (SON) or in AVP neurons of either the
PVN or SON. Expression of OXT receptor mRNA in the medial preoptic area and amygdala of the control groups was
also higher in MP females than in NP females. Finally, we demonstrated that infusion of OXT into the lateral
ventricle of NP females promoted preferences for pup odors. These results indicate that puerperal and parental
experiences enhance the responsiveness of OXT neurons in the PVN to pup stimuli and establish olfactory
preferences for these odors in a parity-dependent manner. 相似文献
10.
Takenori Kawabata Dhugal J. Lindsay Minoru Kitamura Satoshi Konishi Jun Nishikawa Shuhei Nishida Michiya Kamio Hiroshi Nagai 《Fisheries Science》2013,79(3):487-494
Many polypeptides isolated from shallow water cnidarian species have been utilized as valuable biochemical tools in both basic and applied biological sciences. Deepwater cnidarian species might be another potential resource for novel biochemical tools. However, because of limited access to cnidarian samples from deep-sea environments, bioactive polypeptides have never before been reported from this group. In this study, we collected twelve deep-sea jellyfish species (nine hydrozoans and three scyphozoans) using a plankton net that was specially designed for collecting deep-sea organisms, and prepared water-soluble extracts, presumably containing polypeptides, of these jellyfishes. The extracts were subjected to cytotoxicity, hemolytic activity, and crustacean lethal toxicity tests. In the cytotoxicity test, six out of the nine tested hydrozoan species showed activity. In the hemolytic activity test, only three hydrozoans showed activity and none of the scyphozoan jellyfishes showed activity. In the crustacean lethality test, two hydrozoan jellyfishes and all three of the tested scyphozoan jellyfishes showed lethal activity. These results revealed a high incidence of water-soluble bioactive substances occurring in these deep-sea jellyfishes. Furthermore, all the heat-treated and the methanol-treated crude jellyfish extracts lost their bioactivities. Thus, it is likely that the bioactive compounds in the water-soluble extracts were unstable polypeptides (proteins). This is the first published report on bioactivities in extracts from deep-sea jellyfishes. 相似文献