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71.
Wataru Higuchi Mineo Muramatsu Soshi Dohmae Tomomi Takano Hirokazu Isobe Shizuka Yabe Shi Da Tatiana Baranovich Tatsuo Yamamoto 《Microbiology and immunology》2008,52(11):559-563
The use of probiotics such as Lactobacillus in animal feeds has gained popularity in recent years. In this study the 16S rRNA gene sequence of L. acidophilus in two commercial agents which have been used in animal feeds, LAB‐MOS and Ghenisson 22, was determined. Phylogenetic tree analysis revealed that the two agents, strain MNFLM01 in LAB‐MOS and strain GAL‐2 in Ghenisson 22, belonged to L. rhamnosus (a member of the L. casei group) and L. johnsonii (a member of the L. acidophilus group), respectively. Biochemical tests assigned the two as L. rhamnosus and ambiguously as L. acidophilus. The data suggest that 16S rRNA gene sequence analysis provides more accurate identification of Lactobacillus species than biochemical tests and would allow quality assurance of relevant commercial products. The 16S rRNA gene sequences of strains MNFLM01 and GAL‐2 determined in this study have been submitted to the DDBJ/EMBL/GenBank accession numbers under accession numbers AB288235 and AB295648, respectively. 相似文献
72.
Endothelial cell lineages of the heart 总被引:1,自引:0,他引:1
During early gastrulation, vertebrate embryos begin to produce endothelial cells (ECs) from the mesoderm. ECs first form primitive
vascular plexus de novo and later differentiate into arterial, venous, capillary, and lymphatic ECs. In the heart, the five distinct EC types (endocardial,
coronary arterial, venous, capillary, and lymphatic) have distinct phenotypes. For example, coronary ECs establish a typical
vessel network throughout the myocardium, whereas endocardial ECs form a large epithelial sheet with no angiogenic sprouting
into the myocardium. Neither coronary arteries, veins, and capillaries, nor lymphatic vessels fuse with the endocardium or
open to the heart chamber. The developmental stage during which the specific phenotype of each cardiac EC type is determined
remains unclear. The mechanisms involved in EC commitment and diversity can however be more precisely defined by tracking
the migratory patterns and lineage decisions of the precursors of cardiac ECs.
Work carried out by the authors is supported in part by the NIH. 相似文献
73.
74.
Hiroko Nishida Hiroto Yamazaki Satoshi Iwata Takeshi Inukai Yasuo Ikeda 《Biochemical and biophysical research communications》2009,382(1):57-687
Cancer stem cell (CSC) theory suggests that only a small subpopulation of cells having stem cell-like potentials can initiate tumor development. While recent data on acute lymphoblastic leukemia (ALL) are conflicting, some studies have demonstrated the existence of such cells following CD34-targeted isolation of primary samples. Although CD34 is a useful marker for the isolation of CSCs in leukemias, the identification of other specific markers besides CD34 has been relatively unsuccessful. To identify new markers, we first performed extensive analysis of surface markers on several B-ALL cell lines. Our data demonstrated that every B-ALL cell line tested did not express CD34 but certain lines contained cell populations with marked heterogeneity in marker expression. Moreover, the CD9+ cell population possessed stem cell characteristics within the clone, as demonstrated by in vitro and transplantation experiments. These results suggest that CD9 is a useful positive-selection marker for the identification of CSCs in B-ALL. 相似文献
75.
Reiko Sakaguchi Takashi Endoh Seigo Yamamoto Kazuki Tainaka Kenji Sugimoto Nobutaka Fujieda Shigeki Kiyonaka Yasuo Mori Takashi Morii 《Bioorganic & medicinal chemistry》2009,17(20):7381-7386
A fluorescent sensor for the detection of inositol-1,3,4,5-tetrakisphosphate, Ins(1,3,4,5)P4, was constructed from a split PH domain and a single circularly permuted GFP. A structure-based design was conducted to transduce a ligand-induced subtle structural perturbation of the split PH domain to an alteration in the population of the protonated and the deprotonated states of the GFP chromophore. Excitation of each distinct absorption band corresponding to the protonated or the deprotonated state of GFP resulted an increase and a decrease, respectively, in the intensity of emission spectra upon addition of Ins(1,3,4,5)P4 to the split PH domain-based sensor. The Ins(1,3,4,5)P4 sensor retained the ligand affinity and the selectivity of the parent PH domain, and realized the ratiometric fluorescence detection of Ins(1,3,4,5)P4. 相似文献
76.
Kubota M Narita K Murayama T Suzuki S Soga S Usukura J Ogawa Y Kuba K 《Cell calcium》2005,38(6):557-567
Ca(2+)-induced Ca2+ release (CICR) occurs in frog motor nerve terminals after ryanodine receptors (RyRs) are primed for activation by conditioning large Ca2+ entry. We studied which type of RyR exists, whether CICR occurs without conditioning Ca2+ entry and how RyRs are primed. Immunohistochemistry revealed the existence of RyR3 in motor nerve terminals and axons and both RyR1 and RyR3 in muscle fibers. A blocker of RyR, 8-(N,N-diethylamino)octyl 3,4,5-trimethoxybenzoate hydrochloride (TMB-8) slightly decreased rises in intracellular Ca2+ ([Ca2+]i) induced by a short tetanus (50 Hz, 1-2s), but not after treatment with ryanodine. Repetitive tetani (50 Hz for 15s every 20s) produced repetitive rises in [Ca2+]i, whose amplitude overall waxed and waned. TMB-8 blocked the waxing and waning components. Ryanodine suppressed a slow increase in end-plate potentials (EPPs) induced by stimuli (33.3 Hz, 15s) in a low Ca2+, high Mg2+ solution. KN-62, a blocker of Ca(2+)/calmoduline-activated protein kinase II (CaMKII), slightly reduced short tetanus-induced rises in [Ca2+]i, but markedly the slow waxing and waning rises produced by repetitive tetani in both normal and low Ca2+, high Mg2+ solutions. Likewise, KN-62, but not KN-04, an inactive analog, suppressed slow increases in EPP amplitude and miniature EPP frequency during long tetanus. Thus, CICR normally occurs weakly via RyR3 activation by single impulse-induced Ca2+ entry in frog motor nerve terminals and greatly after the priming of RyR via CaMKII activation by conditioning Ca2+ entry, thus, facilitating transmitter exocytosis and its plasticity. 相似文献
77.
78.
Katayama K Wada K Miyoshi H Ohashi K Tachibana M Furuki R Mizuguchi H Hayakawa T Nakajima A Kadowaki T Tsutsumi Y Nakagawa S Kamisaki Y Mayumi T 《FEBS letters》2004,560(1-3):178-182
Peroxisome proliferator-activated receptor γ (PPARγ) plays a central role in adipocyte differentiation and insulin sensitivity. Although PPARγ also appears to regulate diverse cellular processes in other cell types such as lymphocytes, the detailed mechanisms remain unclear. In this study, we established a lentivirus-mediated short hairpin RNA expression system and identified a potent short hairpin RNA which suppresses PPARγ expression, resulting in marked inhibition of preadipocyte-to-adipocyte differentiation in 3T3-L1 cells. Our PPARγ-knockdown method will serve to clarify the PPARγ pathway in various cell types in vivo and in vitro, and will facilitate the development of therapeutic applications for a variety of diseases. 相似文献
79.
Usuda K Wada Y Ishimaru Y Kobayashi T Takahashi M Nakanishi H Nagato Y Mori S Nishizawa NK 《Plant biotechnology journal》2009,7(1):87-95
Nicotianamine (NA), a metal chelator ubiquitous in higher plants, serves as an antihypertensive substance in humans. To engineer a novel antihypertensive rice that contains larger amounts of NA, the barley NA synthase gene, HvNAS1 , was introduced into rice via Agrobacterium -mediated transformation. The introduced HvNAS1 was driven by pGluB-1 , which induces strong gene expression in the endosperm of rice seeds. The NA content in transgenic rice seeds was up to fourfold greater than that in non-transgenic rice seeds. The Cre/ loxP DNA excision (CLX) system was used to remove the selectable marker gene for antibiotic resistance. Furthermore, the transgenic rice was crossed with a cleistogamous mutant to prevent gene transfer via pollen dispersal. These two modifications may minimize public concern with regard to the use of this transgenic rice. 相似文献
80.
Osamu Yamauchi Tatsuo Yajima Rie Fujii Yuichi Shimazaki Masanobu Yabusaki Masako Takani Minoru Tashiro Takeshi Motoyama Mitsuhiro Kakuto Yasuo Nakabayashi 《Journal of inorganic biochemistry》2008,102(5-6):1218
Intramolecular M(II)H–C interactions (M(II)=Cu(II), Pd(II)) involving a side chain alkyl group of planar d8 and d9 metal complexes of the N-alkyl (R) derivatives of N,N-bis(2-pyridylmethyl)amine with an N3Cl donor set were established by structural and spectroscopic methods. The methyl group from the branched alkyl group (R = 2,2-dimethylpropyl and 2-methylbutyl) axially interacts with the metal ion with the MC and MH distances of 3.056(3)–3.352(9) and 2.317(1)–2.606(1) Å, respectively, and the M–H–C angles of 122.4–162.3°. The Cu(II) complexes showing the interaction have a higher redox potential as compared with those without it, and the 1H NMR signals of the interacting methyl group in Pd(II) complexes shifted downfield relative to the ligand signals. Dependence of the downshift values on the dielectric constants of the solvents used indicated that the M(II)H–C interaction is mainly electrostatic in nature and may be regarded as a weak hydrogen bond. Implications for possible environmental effects of the leucine alkyl group at the type 1 Cu site of fungal laccase are also discussed. 相似文献