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101.
Ichida M Yui Y Yoshioka K Tanaka T Wakamatsu T Yoshikawa H Itoh K 《FEBS letters》2011,585(24):4018-4024
We showed that the migration, morphology and adhesiveness of undifferentiated mesenchymal cells dramatically changed during osteogenic differentiation. The migration of these cells was transiently upregulated early in osteogenic differentiation. At a later stage, migration was decreased but adhesiveness was increased. Furthermore, Cdc42 and Rac1 Rho-family small GTPases were activated at early stages of differentiation and the phosphorylation level of FAK decreased as differentiation progressed. We also showed cell migration was promoted by inhibition of the Rho-ROCK-myosin signaling. Finally, using a mouse model of ectopic bone formation, we confirmed that treatment with ROCK inhibitor, Y-27632 increased cell movement into bone formation sites, resulting in enhanced osteogenesis. These results provide a new insight into the link between cell migration and osteogenic differentiation. 相似文献
102.
Many pathogens important for medicine, veterinary medicine or public health belong to the genera alphavirus and rubivirus within the family Togaviridae. 29 species of alphaviruses have been reported, and most of them are arboviruses. Chikungnya virus re-emerged in Kenya in 2004 and the epidemics spread to the Indian Ocean islands and many countries in South Asia, South-East Asia and Europe. On the other hand, rubella virus, a sole member of the genus rubivirus, is the causative agent of rubella and congenital rubella syndrome (CRS). Because human is only a natural host of the virus and effective live attenuated vaccines are available, immunization activities are strengthened globally to eliminate rubella and CRS, together with measles. 相似文献
103.
Kiyoko Taniai Chikara Hirayama Kazuei Mita Kiyoshi Asaoka 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2014,184(7):827-834
Four glycine-rich protein (GRP) genes were identified from expressed sequence tags of the maxillary galea of the silkworm. All four genes were expressed in the maxillary pulp, antenna, labrum, and labium, but none of the genes were expressed in most internal organs. Expression of one of the genes, termed bmSIGRP, was further increased approximately fivefold in the mouth region (including the maxilla, antenna, labrum, labium, and mandible) after 24 h of starvation. bmSIGRP expression peaked at 24 h and gradually declined during the subsequent 2 days. When a synthetic diet not containing proteins was fed, bmSIGRP expression increased significantly in the mouth region to levels similar to that observed in starved larvae. Synthetic diets that lacked vitamins or salts but contained amino acids did not significantly affect bmSIGRP expression. These results suggest that amino acid depletion increases bmSIGRP expression. 相似文献
104.
Jun Nishihiro Munemitsu Akasaka Mifuyu Ogawa Noriko Takamura 《Ecological Research》2014,29(3):369-369
This data paper describes the native vascular aquatic plant floras of 268 Japanese lakes recorded from 1899–2011. The data were compiled from 201 literature sources, most of which were written in Japanese and published in local journals or individual reports rather than in major scientific journals. The literature was searched using web-based services (i.e., Google Scholar, http://scholar.google.com/; CiNii, http://ci.nii.ac.jp/en; JDreamII, http://pr.jst.go.jp/jdream2/; and ISI, http://apps.webofknowledge.com) and by private communication with experts or local governments. Scientific names were consolidated under currently-accepted nomenclature. Four datasets, FloraDB, LakeDB, SpeciesDB, and LiteratureDB, were created to include records of the flora of each lake in each year, the names and locations of the lakes, the scientific names and synonyms of the aquatic vascular plants, and a literature list, respectively. These data can be used to study long-term changes in the species composition and/or richness of aquatic plants in Japanese lakes. 相似文献
105.
Shiki Takamura Eiji Kajiwara Sachiyo Tsuji-Kawahara Tomoko Masumoto Makoto Fujisawa Maiko Kato Tomomi Chikaishi Yuri Kawasaki Saori Kinoshita Manami Itoi Nobuo Sakaguchi Masaaki Miyazawa 《PLoS pathogens》2014,10(3)
In chronic viral infections, persistent antigen presentation causes progressive exhaustion of virus-specific CD8+ T cells. It has become clear, however, that virus-specific naïve CD8+ T cells newly generated from the thymus can be primed with persisting antigens. In the setting of low antigen density and resolved inflammation, newly primed CD8+ T cells are preferentially recruited into the functional memory pool. Thus, continual recruitment of naïve CD8+ T cells from the thymus is important for preserving the population of functional memory CD8+ T cells in chronically infected animals. Friend virus (FV) is the pathogenic murine retrovirus that establishes chronic infection in adult mice, which is bolstered by the profound exhaustion of virus-specific CD8+ T cells induced during the early phase of infection. Here we show an additional evasion strategy in which FV disseminates efficiently into the thymus, ultimately leading to clonal deletion of thymocytes that are reactive to FV antigens. Owing to the resultant lack of virus-specific recent thymic emigrants, along with the above exhaustion of antigen-experienced peripheral CD8+ T cells, mice chronically infected with FV fail to establish a functional virus-specific CD8+ T cell pool, and are highly susceptible to challenge with tumor cells expressing FV-encoded antigen. However, FV-specific naïve CD8+ T cells generated in uninfected mice can be primed and differentiate into functional memory CD8+ T cells upon their transfer into chronically infected animals. These findings indicate that virus-induced central tolerance that develops during the chronic phase of infection accelerates the accumulation of dysfunctional memory CD8+ T cells. 相似文献
106.
Kiyoko Kaneko Hiro Iwamoto Makoto Yasuda Katsunori Inazawa Noriko Yamaoka Tomoko Fukuuchi 《Nucleosides, nucleotides & nucleic acids》2014,33(4-6):199-207
To examine the role of matrix proteins in the formation of gouty tophus, we analyzed the crystalline components and matrix proteins in a gouty tophus from a patient with recurrent gout. Micro-area X-ray diffraction analysis and infrared spectroscopy indicated that the tophus was composed of monosodium urate monohydrate. Proteomic analysis identified 134 proteins from the tophus as matrix proteins. Many proteins relevant to inflammation and host defense were identified, and immunoglobulin was detected in all four extracted fractions (KCl, formic acid, guanidine-HCl, and ethylenediaminetetraacetic acid) and from many spots throughout a broad molecular weight range after electrophoresis. It is thought that the process of biological defense including the immunity has occurred in the gouty tophus. 相似文献
107.
Yuji Shimizu Shimpei Sato Jun Koyamatsu Hirotomo Yamanashi Mako Nagayoshi Koichiro Kadota Mami Tamai Kazuhiko Arima Hironori Yamasaki Yosuke Kusano Noboru Takamura Takahiro Maeda 《Journal of physiological anthropology》2014,33(1):7
Background
Renal impairment is known to be associated with atherosclerosis, which in turn is reported to be positively associated with hemoglobin levels. In addition, renal impairment is known to be associated with a form of anemia known as renal anemia.Methods
To clarify the associations between renal impairment and anemia, we conducted a cross-sectional study of 1,105 60 to 89-year-old men, who were not taking medication for anemia and were undergoing general health check-ups.Results
Compared with non-chronic kidney disease, chronic kidney disease (CKD) with a glomerular filtration rate (GFR) <60 mL/min/1.73 m2 was found to constitute a significant risk of anemia. However, we noted that this risk was lower for mild renal impairment (60 mL/min/1.73 m2 ≤ GFR <90 mL/min/1.73 m2). Compared with the non-CKD reference group, the classical cardiovascular risk factors adjusted odds ratio (OR) for anemia was 1.81 (1.23 to 2.68) and compared with the normal renal function (GFR ≥90 mL/min/1.73 m2) reference group, the ORs for mild renal impairment and CKD were 0.26 (0.15 to 0.47) and 0.60 (0.33 to 1.09).Conclusions
Independent from classical cardiovascular risk factors, CKD, which was identified during general health check-ups, appeared to constitute a significant risk of anemia for older Japanese men. For mild renal impairment, however, this association was a reduced risk of anemia and thus possibly a higher risk of atherosclerosis. 相似文献108.
Species richness of Protozoa in Japanese lakes 总被引:2,自引:0,他引:2
The protozoan fauna and species richness in the pelagic zone of 15 Japanese lakes were investigated in 1996 using polyurethane
foam (PF) substrates. The most common species were flagellates, such as Cryptomonas erosa, Oikomonas termo, and Pleuromonas jaculans. Cinetochilum margaritaceum and Actinophrys sol were the most common species of the Ciliata and Sarcodina, respectively. The similarity of species occurrence was calculated
from presence/absence data, but this revealed no clear trend with respect to the influence of lake properties such as trophic
state, surface area, or mean depth. The occurrence pattern of Protozoa was most similar in L. Chuzenji and L. Biwa (north
basin), two oligomesotrophic natural lakes. Log species richness was positively correlated with log total phosphorus (r = 0.54, P < 0.05) and negatively with log mean depth (r = −0.58, P < 0.05). The diversity index (Margalef's formula), highly correlated with the total species number (r = 0.85, P < 0.01), was negatively correlated with log lake area (r = −0.71, P < 0.01). The logarithm of Phytomastigophora number was positively correlated with log total nitrogen (r = 0.53, P < 0.05), and the logarithm of Ciliata number was negatively correlated with log lake area (r = −0.55, P < 0.05). The species richness of Protozoa on PF substrates was determined by both the nutrient status of the lake and the
distance from the location of the suspended PF substrate to the lake bottom or shore.
Received: September 25, 1999 / Accepted: January 6, 2000 相似文献
109.
Expression of epidermis-specific antigens during embryogenesis of the ascidian, Halocynthia roretzi 总被引:7,自引:0,他引:7
We have produced two monoclonal antibodies (Epi-1 and Epi-2) which specifically recognize epidermal cells and their derivative, the larval tunic, of developing embryos of the ascidian Halocynthia roretzi. The antigens, examined by indirect immunofluorescence staining, first appear at the early tailbud stage and are present until at least the swimming larval stage. There were distinct and separate puromycin and actinomycin D sensitivity periods for each antigen. Aphidicolin, a specific inhibitor of DNA synthesis, prevented the appearance of each antigen when embryos were exposed to the drug continuously from cleavage stages. These results suggest that the antigens are synthesized during embryogenesis by developing epidermal cells and that several rounds of DNA replication are required for the antigen expression. Early cleavage stage embryos, including fertilized but unsegmented eggs, in which cytokinesis had been blocked with cytochalasin B expressed the antigens, and blastomeres exhibiting the antigens were always of the epidermis lineage. In partial embryos produced by four separated blastomere pairs of the 8-cell embryos, the expression of antigens was seen only in those developed from the animal blastomere pairs, which are progenitors of epidermal cells. These observations indicate that differentiation of epidermal cells in ascidian embryos takes place in a typical "mosaic" fashion. 相似文献
110.
Diurnal changes in the vertical distribution of phytoplankton in hypertrophic Lake Kasumigaura,Japan 总被引:3,自引:1,他引:3
The daily vertical migration of five species;Microcystis aeruginosa (Kütz.) Trevis,Anabaena spiroides Klebahn f.crassa (L.) Elenkin,Aphanizomenon flos-aquae (L.) Ralfs,Melosira granulata (E). Ralfs, andCoscinodiscus lacustris Grun. was studied using a close-interval water sampler on a calm summer day in Lake Kasumigaura. Many colonies ofMicrocystis were observed at the middle of the water column (approx. 1.5 m depth) in the afternoon, and at the surface in the early morning.Anabaena occurred mostly in the upper layer whileAphanizomenon tended to be uniformly distributed. The difference in migration patterns suggests thatMicrocystis is superior toAnabaena andAphanizomenon in obtaining both light and nutrients from this lake. Among diatoms,Melosira remained at the bottom of the water column throughout day and night, but Coscinodiscus was uniformly distributed. 相似文献