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81.
Tatsuya Unuma Akifumi Nakamura Keisuke Yamano Yukio Yokota 《Molecular reproduction and development》2010,77(1):59-68
Major yolk protein (MYP), the predominant component of yolk granules in sea urchin eggs, is also contained in the coelomic fluid and nutritive phagocytes of the gonad in both sexes. MYP is stored in ovarian and testicular nutritive phagocytes prior to gametogenesis and is used during gametogenesis as material for synthesizing proteins and other components necessary for eggs and sperm. To reveal the expression profile and the main production site of MYP, we analyzed MYP mRNA expression in immature and maturing Pseudocentrotus depressus. Real‐time reverse‐transcribed polymerase chain reaction analysis showed that MYP mRNA was expressed predominantly in the digestive tract (stomach, intestine and rectum) and the gonad of both sexes. The total amounts of MYP mRNA in the whole digestive tract and in the whole gonad were at similar levels in both immature and maturing sea urchins. MYP mRNA was also detected in white morula cells and vibratile cells separated from the coelomic fluid by density gradient centrifugation, but the expression levels in these cells were very low compared with those in the digestive tract and the gonad. Using in situ hybridization analysis, MYP mRNA was detected in the inner epithelium of the digestive tract and in nutritive phagocytes of the ovary and testis, but was not detected in the germ cells. We conclude that the adult sea urchin has two predominant production sites for MYP regardless of sex and reproductive stage: the inner epithelium of the digestive tract and the nutritive phagocytes of the gonad. Mol. Reprod. Dev. 77: 59–68, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
82.
Koji Sode Masahiro Tatara Haruko Takeyama J. Grant Burgess Tadashi Matsunaga 《Applied microbiology and biotechnology》1992,37(3):369-373
Summary Versatility of gene transfer by transconjugation in marine cyanobacteria was demonstrated. In this study, seven different marine cyanobacteria were used as recipient cells. First, transconjugation was carried out using the mobilizable transposon (Tn5) carrying plasmid pSUP1021. Transconjugants were observed in all marine cyanobacteria tested. Second, the broad-host-range vector pKT230 (IncQ) was tested for transconjugation. pKT230 has been successfully transferred in a marine cyanobacterium Synechococcus sp. NKBG15041C, and replicated as an autonomous replicon without alteration in the restriction enzyme pattern. A maximum transfer efficiency of 5.2 × 10–4 transconjugants/recipient cell was observed, when mating was performed on agar plates containing low salinity (0.015 m NaCl) medium. This is the first study to demonstrate gene transfer in marine cyanobacteria via transconjugation.
Correspondence to: K. Sode 相似文献
83.
Objectives
This study focuses on East Asian countries and investigates the difference in the marriage premium on the health-marriage protection effect (MPE) between younger and older generations and the intra-couple education concordance effect (ECE) on the health of married individuals. This study used inter-country comparative data from China, Japan, and Korea.Methods
This study focused on individuals (n = 7,938) in China, Japan, and Korea who were sampled from the 2010 East Asian Social Survey. To investigate MPE and ECE, four health indicators were utilized: a physical and mental components summary (PCS and MCS), self-rated health status (Dself), and happiness level (Dhappy). Ordinary least squares regression was conducted by country- and gender-specific subsamples.Results
We found that the MPE on PCS, MCS, and Dself was more significant for the older generation than for the younger generation in both China and Japan, whereas the results were inconclusive in Korea. With regard to the ECE on happiness (Dhappy), for both men and women, couples tend to be happier when both the husband and the wife are well educated (“higher balanced marriage”) compared to couples with a lower level of educational achievement (“lower balanced marriage”). Significant benefits from a “higher balanced marriage” on MCS and Dself were observed for women only. In contrast, no statistically significant differences in health status were observed between “higher balanced marriage” couples and couples with different levels of educational achievements (“upward marriage” or “downward marriage”).Conclusions
This study found that (1) the MPE was more significant for the older generation, and (2) the health gap, particularly the happiness gap, between higher- and lower-balanced married couples was significant. The inter-country comparative findings are useful to explain how the role of marriage (and therefore of family) on health has been diluted due to the progress of industrialization and modernization. 相似文献84.
Interpretation of the stokes radius of macromolecules determined by gel filtration chromatography 总被引:4,自引:0,他引:4
From a comparison of the gel chromatographic properties of large randomly-coiled polypeptides in 6 M guanidine hydrochloride and of large globular proteins, we found that the distribution coefficient was more closely correlated with the intrinsic viscosity-based Stokes radius than with the translational frictional coefficient-based Stokes radius. This means that the effect of the hydrodynamic flow of dissolved molecules during gel chromatography should be considered. The ratio of transport of solute by bulk flow as compared with that by net diffusion (i.e., Brownian motion) is large under some conditions. On the other hand, we consider that the distribution coefficient obtained in static equilibrium experiments should be determined by the translational frictional coefficient-based Stokes radius, since the solvent does not flow. On this basis, we discuss the meaning of the Stokes radius and the separation mechanism of macromolecules by gel filtration. 相似文献
85.
Iketani M Nishimura H Akayama K Yamano Y Morishima I 《Insect biochemistry and molecular biology》1999,29(1):19-24
Various peptidoglycan fragments, different in mode of cross-linking and molecular size, were isolated, and the elicitor activity was tested for induction of antibacterial protein synthesis in larvae of Bombyx mori. Linear uncross-linked peptidoglycans from Bacillus licheniformis and Micrococcus luteus were effective elicitors, similar to the directly cross-linked peptidoglycan from B. licheniformis cell wall. The fragments of uncross-linked peptidoglycan with a sugar chain length of four or more were active elicitors, but the disaccharide unit had no elicitor activity. The minimum structure of peptidoglycan required for induction of antibacterial protein synthesis was determined to be two repeating N-acetylglucosamine-N-acetylmuramic acid units with peptide side chains. 相似文献
86.
To investigate the functional expression of adenosine A3 receptor (A3AR) in mammalian living tissues, we generated an apoaequorin-transgenic mouse that expresses jellyfish apoaequorin
throughout its body. The expression of apoaequorin under the control of a strong CAG promoter was detected in various tissues,
including the abdominal skin, adipose, ear, brain, esophagus, heart, inferior vena cava vessel, kidney, lens, liver, lung,
pancreas, skeletal muscle, spleen, tail, testis, and thymus. The transgene was mapped to the C1–2 region of chromosome 16
by Fluorescence in situ hybridization analysis. Among these transgenic mouse tissues, we succeeded in detecting elevated responses
of intracellular Ca2+ as a light emission of aequorin induced by the A3AR agonist in the pancreas, brain, and testis, the last two of which are
known to be main tissues abundantly expressing A3AR. The A3AR agonist led to the phosphorylation of both extracellular signal-regulated
kinase 1/2 and protein kinase B in mouse pancreas, and all the intracellular responses via A3AR were antagonized by the A3AR-specific
antagonist. In addition, the mRNA expression of A3AR and the A3AR-induced intracellular responses were also found in the rat
pancreatic acinar cell line AR42J. These results suggest that pancreas is one of the main tissues functionally expressing
A3AR in mammalians in vivo, and that the present approach using transgenic mice that express apoaequorin throughout their bodies will facilitate the
functional analysis of proteins of interest.
Kazuya Yamano and Katsuhiro Mori contributed equally to this work 相似文献
87.
1,8-Cineole inhibits root growth and DNA synthesis in the root apical meristem ofBrassica campestris L. 总被引:2,自引:0,他引:2
Ritsuko Koitabashi Takeshi Suzuki Tamotsu Kawazu Atsushi Sakai Haruko Kuroiwa Tsuneyoshi Kuroiwa 《Journal of plant research》1997,110(1):1-6
1,8-cineole is a volatile growth inhibitor produced bySalvia species. We examined the effect of this allelopathic compound on the growth of other plants usingBrassica campestris as the test plant. Cineole inhibited germination and growth ofB. campestris in a dosedependent manner. WhenB. campestris was grown for 5 days with various concentrations of cineole, the length of the roots was found to be shorter as the concentration
of cineole increased, whereas the length of the hypocotyl remained constant up to 400 μM cineole, indicating that cineole
specifically inhibited growth of the root. The mitotic index in the root apical meristem of 3-day-old seedlings decreased
from 5.6% to 1.6% when exposed to 400 μM cineole, showing that cineole inhibits the proliferation of root cells. We then examined
the effect of cineole on DNA synthesis by indirect immunofluorescence microscopy using antibody raised against 5-bromo-2′-deoxyuridine
(BrdU, an analogue of thymidine) in thin sections of samples embedded in Technovit 7100 resin. The results clearly demonstrated
that cineole inhibits DNA synthesis in both cell nuclei and organelles in root apical meristem, suggesting that cineole may
interfere with the growth of other plant species by inhibiting DNA synthesis in the root apical meristem. 相似文献
88.
Umemoto E Otani K Ikeno T Verjan Garcia N Hayasaka H Bai Z Jang MH Tanaka T Nagasawa T Ueda K Miyasaka M 《Journal of immunology (Baltimore, Md. : 1950)》2012,189(1):191-199
Although the spleen plays an important role in host defense against infection, the mechanism underlying the migration of the innate immune cells, plasmacytoid dendritic cells (pDCs), into the spleen remains ill defined. In this article, we report that pDCs constitutively migrate into the splenic white pulp (WP) in a manner dependent on the chemokine receptors CCR7 and CXCR4. In CCR7-deficient mice and CCR7 ligand-deficient mice, compared with wild-type (WT) mice, substantially fewer pDCs were found in the periarteriolar lymphoid sheath of the splenic WP under steady-state conditions. In addition, the migration of adoptively transferred CCR7-deficient pDCs into the WP was significantly worse than that of WT pDCs, supporting the idea that pDC trafficking to the splenic WP requires CCR7 signaling. WT pDCs responded to a CCR7 ligand with modest chemotaxis and ICAM-1 binding in vitro, and priming with the CCR7 ligand enabled the pDCs to migrate efficiently toward low concentrations of CXCL12 in a CXCR4-dependent manner, raising the possibility that CCR7 signaling enhances CXCR4-mediated pDC migration. In agreement with this hypothesis, CCL21 and CXCL12 were colocalized on fibroblastic reticular cells in the T cell zone and in the marginal zone bridging channels, through which pDCs appeared to enter the WP. Furthermore, functional blockage of CCR7 and CXCR4 abrogated pDC trafficking into the WP. Collectively, these results strongly suggest that pDCs employ both CCR7 and CXCR4 as critical chemokine receptors to migrate into the WP under steady-state conditions. 相似文献
89.
Hitoshi Sashiwa Shizu Fujishima Naoko Yamano Norioki Kawasaki Atsuyoshi Nakayama Einosuke Muraki Mongkol Sukwattanasinitt Rath Pichyangkura andSei-ichi Aiba 《Carbohydrate polymers》2003,51(4):391-395
N-Acetyl-
-glucosamine (GlcNAc) was produced from chitin by use of crude enzyme preparations. The efficient production of GlcNAc by cellulases derived from Trichoderma viride (T) and Acremonium cellulolyticus (A) was observed by HPLC analysis compared to lipase, hemicellulase, and pectinase. β-Chitin showed higher degradability than α-chitin when using cellulase T. The optimum pH of cellulase T was 4.0 on the hydrolysis of β-chitin. The yield of GlcNAc was enhanced by mixing of cellulase T and A. 相似文献
90.
Yohei Takeda Vuong N. Bui Kenta Iwasaki Takaaki Kobayashi Haruko Ogawa Kunitoshi Imai 《Biochemical and biophysical research communications》2014
Macrophages play important roles in the host innate immune response and are involved in the onset of diseases caused by inflammation. Toll-like receptor 4 (TLR4)-mediated inflammatory responses of macrophages may be associated with diseases such as diabetes and diseases of the cardiovascular system. Hydroxytyrosol (HT) exerts strong antioxidant and anti-inflammatory effects and may be applied in the treatment of inflammatory diseases. In the present study conducted in vitro, we investigated the effects of the TLR4-dependent anti-inflammatory effect of HT on peritoneal macrophage of BALB/c mice. We show here that the elevated levels of iNOS gene expression and nitric oxide production induced by lipopolysaccharide (LPS) (0.25 μg/ml) were suppressed by HT (12.5 μg/ml). LPS-dependent NF-κB gene expression and phosphorylation of NF-κB were not affected by HT under these conditions. In contrast, the expression of TNF-α was significantly increased in the presence of LPS and HT. These results suggest that HT suppressed nitric oxide production by decreasing iNOS gene expression through a mechanism independent of the NF-κB signaling pathway. These novel findings suggest that the modulation by HT of the expression of genes involved in inflammation may involve multiple mechanisms. 相似文献