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11.
Yoshikawa M Nishiofuku M Moriya K Ouji Y Ishizaka S Kasahara K Mikasa K Hirai T Mizuno Y Ogawa S Nakamura T Maruyama H Akao N 《Parasitology international》2008,57(4):525-529
We present 3 adult cases of visceral toxocariasis from the same family, who each consumed thin slices of raw bovine liver weekly, and developed eosinophilia and multiple small lesions in their livers and lungs. Serological examinations using the larval excretory–secretory product of Toxocara canis strongly indicated infection with Toxocara species larvae. The patients responded well to treatment with albendazole. Ingestion of raw liver from paratenic animals is considered to be a common transmission route of human toxocariasis, especially in adults. 相似文献
12.
Suga H Sasaki G Kuma K Nishiyori H Hirose N Su ZH Iwabe N Miyata T 《FEBS letters》2008,582(5):815-818
Animal-specific gene families involved in cell-cell communication and developmental control comprise many subfamilies with distinct domain structures and functions. They diverged by subfamily-generating duplications and domain shufflings before the parazoan-eumetazoan split. Here, we have cloned 40 PTK cDNAs from choanoflagellates, Monosiga ovata, Stephanoeca diplocostata and Codosiga gracilis, the closest relatives to animals. A phylogeny-based analysis of PTKs revealed that 40 out of 47 subfamilies analyzed have unique domain structures and are possibly generated independently in animal and choanoflagellate lineages by domain shufflings. Seven cytoplasmic subfamilies showed divergence before the animal-choanoflagellate split originated by both duplications and shufflings. 相似文献
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Tanaka Y Iguchi K Yoshimura J Nakagiri N Tainaka K 《Journal of theoretical biology》2011,268(1):98-104
Ayu fish form algae-feeding territories in a river during a non-breeding (growing) season. We build a cost-benefit theory to describe the breakdown and formation of territory. In the early stage of a growing season, all fish hold territories at low densities. Once all territory sites are occupied, excess fish become floaters. When fish density further increases, a phase transition occurs: all the territories suddenly break down and fish form a school. In contrast, when the fish density is decreased, territories are suddenly formed from the school. Both theory and experiments demonstrate that ayu should exhibit a historical effect: the breakdown and formation processes of territory are largely different. In particular, the theory in formation process predicts a specific fish behavior: an “attempted territory holder” that tries to have a small territory emerges just before the formation of territory. 相似文献
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Matsuoka RL Chivatakarn O Badea TC Samuels IS Cahill H Katayama K Kumar SR Suto F Chédotal A Peachey NS Nathans J Yoshida Y Giger RJ Kolodkin AL 《Neuron》2011,71(3):460-473
In the vertebrate retina, neurites from distinct neuronal cell types are constrained within the plexiform layers, allowing for establishment of retinal lamination. However, the mechanisms by which retinal neurites are segregated within the inner or outer plexiform layers are not known. We find that the transmembrane semaphorins Sema5A and Sema5B constrain neurites from multiple retinal neuron subtypes within the inner plexiform layer (IPL). In Sema5A?/?; Sema5B?/? mice, retinal ganglion cells (RGCs) and amacrine and bipolar cells exhibit severe defects leading to neurite mistargeting into the outer portions of the retina. These targeting abnormalities are more prominent in the outer (OFF) layers of the IPL and result in functional defects in select RGC response properties. Sema5A and Sema5B inhibit retinal neurite outgrowth through PlexinA1 and PlexinA3 receptors both in vitro and in vivo. These findings define a set of ligands and receptors required for the establishment of inner retinal lamination and function. 相似文献
16.
Kei-Ichi Shimazaki Kinjiro Sukegawa 《Bioscience, biotechnology, and biochemistry》2013,77(7):1721-1722
The factors involved in the selective accumulation of ansamitocins P-2, P-3 and P-4 by Actinosynnema pretiosum subsp. pretiosum No. C-15003 (Synonym: Nocardia sp. No. C-15003) were studied. The production of ansamitocin P-2, with a propionyl moiety at the C-3 position of the ansa chain, was stimulated more than 3-fold by the addition of isoleucine, propionate, pro-pionaldehyde and ^-propyl alcohol to the fermentation medium. The production of ansamitocin P-3, with an isobutyryl moiety, was enhanced by the addition of valine, isobutyrate, isobutyraldehyde and isobutyl alcohol, and the proportion of P-3 reached more than 90% of the total ansamitocins produced. The production of P-4, with an isovaleryl moiety, was stimulated by leucine, isovalerate, isovaleraldehyde and isoamyl alcohol. The radioactive compounds, which selectively stimulated the production of each ansamitocin component, were preferentially incorporated into their respective acyl moieties of ansamitocins. Based on these results, we propose that the acyl moieties of ansamitocins P-2, P-3 and P-4 are derived not only through catabolic pathways of the respective amino acids, but also directly from alcohols, aldehydes and fatty acids having the same number of carbon atoms as those of the acyl moieties. 相似文献
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Koshi Kitamura Jin Yoshimura Kei-ichi Tainaka Satoshi Yokojima 《Ecological Research》2009,24(3):533-546
River management often conflicts with the conservation of species in river ecosystems. In Japan, almost all river systems
have been covered by concrete walls. Such river improvement works caused critical damage to river ecosystems. Here we report
the ongoing extinction process of a rare aquatic plant by several consecutive heavy rains. The aquatic plant, Schoenoplectus gemmifer C. Sato, T. Maeda & Uchino, is an extremely rare endemic species that is strictly associated with springwater. The species
is only found in 23 locations in Japan, including only two major habitats: Hamamatsu and Oita. We monitored the population
fluctuations of S. gemmifer at three river systems in Hamamatsu. In the largest habitat, Higashikanda River, the population size of the species decreased
to nearly 1/10th in 2004, due to several severe floods. Spatial and temporal records exhibit four stages of damaging process.
The stepwise damages were found to be caused by a rapid flow of water accelerated by the river improvement work (made in 1985).
The reproduction and growth by seeds and gemmae did not evidently cover the losses by flood washed out. In the other two rivers,
one was extinct and the other is now at the risk of extinction. The modified river structures may be responsible for the near-extinction
of S. gemmifer in Hamamatsu area. We propose two policies for the conservation of this species: (1) the artificial cultivation of gemmae
and seedlings and (2) the modification of river structure to decrease the number of washed-out plants. In particular, it is
important to decrease the water velocity at floods by some methods. 相似文献
19.
Kei-Ichiro Mishiba Kei-Ichi Tawada Masahiro Mii 《In vitro cellular & developmental biology. Plant》2006,42(1):83-88
Summary To pursue the causal factors of ploidy variation in tissue culture of asparagus (Asparagus officinalis L.), ploidy status of stem explants and the calluses induced from these explants were examined using flow cytometry (FCM).
The frequency of higher ploidy (>8C) cells in the stem explants increased with increasing distance from the shoot apex. Calluses
derived from sections far from the apex also showed higher ploidy distributions, and also higher ploidy (16C) in general than
was observed in the explant tissue. Detailed studies using FCM and charge-coupled device (CCD)-equipped fluorescence microscopy
showed that 16C cells appeared in the explant tissues within 1 wk of culture, possibly induced by the plant growth regulators
(PGRs), especially 1-naphthaleneacetic acid (NAA), in the culture medium. 相似文献
20.
Shimanouchi K Takata K Yamaguchi M Murakami S Ishikawa G Takeuchi R Kanai Y Ruike T Nakamura R Abe Y Sakaguchi K 《Journal of biochemistry》2006,139(1):51-58
The damaged DNA-binding protein (DDB) complex consists of a heterodimer of p127 (DDB1) and p48 (DDB2) subunits and is believed to have a role in nucleotide excision repair (NER). We used the GAL4-UAS targeted expression system to knock down DDB1 in wing imaginal discs of Drosophila. The knock-down was achieved in transgenic flies using over-expression of inverted repeat RNA of the D-DDB1 gene [UAS-D-DDB1(650)-dsRNA]. As a consequence of RNA interference (RNAi), the fly had a shrunken wing phenotype. The wing spot test showed induced genome instability in transgenic flies with RNAi knock-down of D-DDB1 in wing imaginal discs. When Drosophila larvae with RNAi knock-down of D-DDB1 in wing imaginal discs were treated with the chemical mutagen methyl methanesulfonate (MMS), the frequency of flies with a severely shrunken wing phenotype increased compared to non-treated transgenic flies. These results suggested that DDB1 plays a role in the response to DNA damaged with MMS and in genome stability in Drosophila somatic cells. 相似文献