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991.
Masaharu Takahashi Shinichi Asabe Yuhko Gotanda Junichi Kishimoto Fumio Tsuda Hiroaki Okamoto 《Biochemical and biophysical research communications》2002,290(1):242-248
When TT virus (TTV) DNA was quantitated in whole blood and plasma aliquots from 27 viremic individuals by real-time detection PCR that can detect essentially all TTV genotypes, the TTV load was 6.9 +/- 3.5 (mean +/- standard deviation)-fold higher in the whole blood than in the plasma samples [P < 0.002 (paired t test)]. To clarify the reason for this difference, peripheral blood cells of various types including red blood cells, granulocytes (CD15+), B cells (CD19+), T cells (CD3+), monocytes (CD14+), and NK cells (CD3-/CD56+) were separated at a purity of 95.4-99.5% from each of three infected individuals with relatively high TTV viremia, and their TTV viral loads were determined. Red blood cells were uniformly negative, but the other cell types were positive for TTV DNA at various titers. In all three patients, the highest TTV load was found in granulocytes (4.2 x 10(4)-3.1 x 10(5) copies/10(6) cells), followed by monocytes (1.4-2.2 x 10(4) copies/10(6) cells) and NK cells (5.4-6.5 x 10(3) copies/10(6) cells); B and T cells were positive, with a low viral load (6.7 x 10(1)-2.7 x 10(3) copies/10(6) cells). These results indicate that TTV is distributed in various peripheral blood cell types at distinct levels, with the highest viral load in granulocytes, and that a significant proportion of the TTV DNA in peripheral blood is not identified by the standard plasma/serum DNA detection methods. 相似文献
992.
Tran Thanh Thu Tran Thi Xuan Mai Eric Dewaele Slama Farsi Yohannes Tadesse Geert Angenon Michel Jacobs 《Molecular breeding : new strategies in plant improvement》2003,11(2):159-168
A requirement for generating transgenic pigeonpea [Cajanuscajan (L.) Millsp] plants is the development of a highly efficientin vitro regeneration procedure. This goal was achieved byusing germinated seedlings grown on B5 medium supplemented with 10 mgl–1 6-benzylaminopurine, which induced differentiatingcallus formation in the cotyledonary node region. The calli were transferred onB5 medium with 0.2 mg l–1 6-benzylaminopurine toobtain shoot induction. Elongated shoots were then further cultured on a B5hormone-free medium for rooting. Using this regeneration system transgenicpigeonpea plants were obtained both by particle bombardment andAgrobacterium tumefaciens-mediated gene transfer. Thepresence of the transgenes in the pigeonpea genome was confirmed by GUS assays,PCR and Southern hybridisation. The transgenic rooted plants were successfullytransferred to soil in the greenhouse. GUS and PCR assays of T1 progeniesconfirmed that the transgenes were stably transmitted to the next generation.This is the first report of successful use ofAgrobacteriumas well as particle bombardment for production of transgenic pigeonpea plants. 相似文献
993.
994.
Hirotaka Imai Kyoko Shinya Ryo Takano Maki Kiso Yukiko Muramoto Saori Sakabe Shin Murakami Mutsumi Ito Shinya Yamada Mai thi Quynh Le Chairul A. Nidom Yuko Sakai-Tagawa Kei Takahashi Yasuyuki Omori Takeshi Noda Masayuki Shimojima Satoshi Kakugawa Hideo Goto Kiyoko Iwatsuki-Horimoto Taisuke Horimoto Yoshihiro Kawaoka 《PLoS pathogens》2010,6(9)
Highly pathogenic H5N1 influenza A viruses have spread across Asia, Europe, and Africa. More than 500 cases of H5N1 virus infection in humans, with a high lethality rate, have been reported. To understand the molecular basis for the high virulence of H5N1 viruses in mammals, we tested the virulence in ferrets of several H5N1 viruses isolated from humans and found A/Vietnam/UT3062/04 (UT3062) to be the most virulent and A/Vietnam/UT3028/03 (UT3028) to be avirulent in this animal model. We then generated a series of reassortant viruses between the two viruses and assessed their virulence in ferrets. All of the viruses that possessed both the UT3062 hemagglutinin (HA) and nonstructural protein (NS) genes were highly virulent. By contrast, all those possessing the UT3028 HA or NS genes were attenuated in ferrets. These results demonstrate that the HA and NS genes are responsible for the difference in virulence in ferrets between the two viruses. Amino acid differences were identified at position 134 of HA, at positions 200 and 205 of NS1, and at positions 47 and 51 of NS2. We found that the residue at position 134 of HA alters the receptor-binding property of the virus, as measured by viral elution from erythrocytes. Further, both of the residues at positions 200 and 205 of NS1 contributed to enhanced type I interferon (IFN) antagonistic activity. These findings further our understanding of the determinants of pathogenicity of H5N1 viruses in mammals. 相似文献
995.
Bateman NW Sun M Bhargava R Hood BL Darfler MM Kovatich AJ Hooke JA Krizman DB Conrads TP 《Journal of proteome research》2011,10(3):1323-1332
The heterogeneity of breast cancer requires the discovery of more incisive molecular tools that better define disease progression and prognosis. Proteomic analysis of homogeneous tumor cell populations derived by laser microdissection from formalin-fixed, paraffin-embedded (FFPE) tissues has proven to be a robust strategy for conducting retrospective cancer biomarker investigations. We describe an MS-based analysis of laser microdissected cancerous epithelial cells derived from twenty-five breast cancer patients at defined clinical disease stages with the goal of identifying protein abundance characteristics indicative of disease progression and recurrence. Comparative analysis of stage 0 and stage III patients revealed 113 proteins that significantly differentiated these groups and included known factors associated with disease pathogenesis, such as CDH1 and CTNNB1, as well as those previously implicated in breast cancer, such as TSP-1. Similar analyses of patients presenting with stage II disease that did or did not exhibit recurrence two years postdiagnosis revealed 42 proteins that significantly differentiated these subgroups and included IRS-1 and PARK7. These data provide evidence supporting the utility of FFPE tissues for functional proteomic analyses and protein biomarker discovery and yielded protein candidates indicative of disease stage and recurrence in breast cancer that warrant further investigation for diagnostic utility and biological relevance. 相似文献
996.
Bacterial lipopolysaccharide and inflammatory mediators augment IL-6 secretion by human endothelial cells 总被引:46,自引:0,他引:46
F R Jirik T J Podor T Hirano T Kishimoto D J Loskutoff D A Carson M Lotz 《Journal of immunology (Baltimore, Md. : 1950)》1989,142(1):144-147
The interaction between human endothelial cells and leukocytes during immunologic and inflammatory responses is in part mediated through the release of soluble mediators. We report that cultured human umbilical vein endothelial cells secrete IL-6 when stimulated with LPS. This effect was inhibited by polymyxin-B. The monokines IL-1 and TNF-alpha were also potent inducers of IL-6, whereas lymphotoxin was only effective at much higher concentrations. Endothelial cell supernatant IL-6 was active as hybridoma-plasmacytoma growth factor and as B-cell stimulating factor. Endothelial IL-6 activity was neutralized by a specific anti-IL-6 antibody and by immunoprecipitation it was shown to be identical in size to human fibroblast-derived IL-6. As IL-6 is possibly an important regulator of host defense responses, production of this cytokine by endothelial cells may contribute to the pathogenesis of various inflammatory and immunologic diseases. 相似文献
997.
Jane M. Waterman Monica Mai 《Ethology : formerly Zeitschrift fur Tierpsychologie》2020,126(12):1122-1130
Animals gather information about their environment from a variety of sources to enable adaptive decision-making behaviour. Eavesdropping on heterospecific alarm calls enhances predator avoidance, reduces time spent vigilant and allows for more time on daily activities such as foraging. If the information is relevant and reliable, individuals that respond to heterospecific signals may benefit from a wider range of information at a low marginal cost. The Cape ground squirrel (Xerus inauris) and crowned lapwing (Vanellus chilensis) are ground-dwelling species that are taxonomically distant but share similar predators, habitat and anti-predatory behaviours. We used playback experiments of the alarm calls produced by conspecifics and lapwings to investigate the vigilance responses of adult female Cape ground squirrels. Squirrels responded with greater vigilance to both squirrel and lapwing alarm calls, and no changes of vigilance levels were observed in response to a control sound. However, contrary to our predictions, changes in vigilance and time to relax did not differ between conspecific versus heterospecific playbacks. The results from our study suggest that squirrels perceive lapwing alarm calls as relevant and reliable information and that responding to it could increase their survival. 相似文献
998.
Calcium-independent activation of hypothalamic type I protein kinase C by unsaturated fatty acids 总被引:9,自引:0,他引:9
Z Naor M S Shearman A Kishimoto Y Nishizuka 《Molecular endocrinology (Baltimore, Md.)》1988,2(11):1043-1048
Among multiple subspecies of the protein kinase C (PKC) family, type I PKC from the hypothalamus, having the structure related to the gamma-sequence, responds to low concentrations of arachidonic acid to exhibit marked enzymatic activity. This mode of activation does not require elevated Ca2+ levels, nor does it depend on diacylglycerol and phospholipid. Type I PKC is expressed only in limited regions of central nervous tissues, such as the hypothalamus. This PKC subspecies is not detected in the pituitary gland. The results suggest that the activation of type I PKC may not always be directly associated with inositol phospholipid hydrolysis, and that this subspecies may play a role in the modulation of specialized functions of the hypothalamus. 相似文献
999.
Seon-Kang Choi Ayako Osawa Takashi Maoka Jun-ichiro Hattan Kei Ito Ai Uchiyama Mai Suzuki Kazutoshi Shindo Norihiko Misawa 《Applied microbiology and biotechnology》2013,97(19):8479-8486
Escherichia coli cells that express the full six carotenoid biosynthesis genes (crtE, crtB, crtI, crtY, crtZ, and crtX) of the bacterium Pantoea ananatis have been shown to biosynthesize zeaxanthin 3,3′-β-d-diglucoside. We found that this recombinant E. coli also produced a novel carotenoid glycoside that contained a rare carbohydrate moiety, quinovose (chinovose; 6-deoxy-d-glucose), which was identified as 3-β-glucosyl-3′-β-quinovosyl zeaxanthin by chromatographic and spectroscopic analyses. The chirality of the aglycone of these zeaxanthin glycosides had been shown to be 3R,3′R, in which the hydroxyl groups were formed with the CrtZ enzyme. It was here demonstrated that zeaxanthin synthesized from β-carotene with CrtR or CYP175A1, the other hydroxylase with similar catalytic function to CrtZ, possessed the same stereochemistry. It was also suggested that the singlet oxygen-quenching activity of zeaxanthin 3,3′-β-d-diglucoside, which has a chemical structure close to the new carotenoid glycoside, was superior to that of zeaxanthin. 相似文献
1000.