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111.
Ishida-Fujii K Goto S Kuboki H Hirano S Sakamoto M Sato M 《BioFactors (Oxford, England)》2004,21(1-4):155-158
Lactic acid bacteria were isolated from an alcohol fermentation broth, and the activity as a probiotic was examined using pathogenic E. coli. Thirty-six strains exhibiting good growth were isolated in the medium of concentrated mush which was a residue resulted in the alcohol distillation process. One of these strains, Lactobacillus paracasei subsp. paracasei I-5, could be grown in the medium containing 8 vol% ethanol and at 45 degrees C. The characteristics were different from the type strain, L. paracasei subsp. paracasei NBRC 15889. L. paracasei I-5 showed an excellent growth in the concentrated mush, which just diluted two-fold and adjusted the pH. ICR mice were fed with a standard germ-free feed (CMF) and the strain I-5 (7 x 10(9) cells/day) was orally administrated for 11 days prior to the intraperitoneal challenge with pathogenic E. coli Juhl. After the challenge, mice administrated the strain I-5 exhibited a high survival rate and survival extension days (p < 0.01) compared with the control. The results suggested that the strain might enhance the animal resistance against microbial pathogens. Neonatal diarrhea caused by E. coli is a serious disease in calf breeding. The strain might be practically valuable to prevent diarrhea in calves. 相似文献
112.
113.
Downregulation of p‐COUMAROYL ESTER 3‐HYDROXYLASE in rice leads to altered cell wall structures and improves biomass saccharification
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Yuri Takeda Yuki Tobimatsu Steven D. Karlen Taichi Koshiba Shiro Suzuki Masaomi Yamamura Shinya Murakami Mai Mukai Takefumi Hattori Keishi Osakabe John Ralph Masahiro Sakamoto Toshiaki Umezawa 《The Plant journal : for cell and molecular biology》2018,95(5):796-811
p‐Coumaroyl ester 3‐hydroxylase (C3′H) is a key enzyme involved in the biosynthesis of lignin, a phenylpropanoid polymer that is the major constituent of secondary cell walls in vascular plants. Although the crucial role of C3′H in lignification and its manipulation to upgrade lignocellulose have been investigated in eudicots, limited information is available in monocotyledonous grass species, despite their potential as biomass feedstocks. Here we address the pronounced impacts of C3′H deficiency on the structure and properties of grass cell walls. C3′H‐knockdown lines generated via RNA interference (RNAi)‐mediated gene silencing, with about 0.5% of the residual expression levels, reached maturity and set seeds. In contrast, C3′H‐knockout rice mutants generated via CRISPR/Cas9‐mediated mutagenesis were severely dwarfed and sterile. Cell wall analysis of the mature C3′H‐knockdown RNAi lines revealed that their lignins were largely enriched in p‐hydroxyphenyl (H) units while being substantially reduced in the normally dominant guaiacyl (G) and syringyl (S) units. Interestingly, however, the enrichment of H units was limited to within the non‐acylated lignin units, with grass‐specific γ‐p‐coumaroylated lignin units remaining apparently unchanged. Suppression of C3′H also resulted in relative augmentation in tricin residues in lignin as well as a substantial reduction in wall cross‐linking ferulates. Collectively, our data demonstrate that C3′H expression is an important determinant not only of lignin content and composition but also of the degree of cell wall cross‐linking. We also demonstrated that C3′H‐suppressed rice displays enhanced biomass saccharification. 相似文献
114.
Several genes which code for theN-acetylglucosaminyltransferases have been cloned and characterized. Physiological and pathophysiological roles of the genes still remain to be elucidated but accumulated evidence suggests that theN-acetylglucosaminyltransferase genes are implicated in differentiation, morphogenesis and cancer metastasis. 相似文献
115.
Tatsuya Koizumi Naoyuki Fujiyama Haruo Katakura 《Entomologia Experimentalis et Applicata》1999,93(2):165-171
The relationships between two phytophagous ladybird beetle species, Epilachna pustulosa K^ono and E. niponica Lewis (Coleoptera, Coccinellidae), and their main host plants, thistles (Cirsium spp., Asteraceae) were investigated in Oshima Peninsula, southern Hokkaido, northern Japan. Epilachna pustulosa was found feeding on Cirsium kamtschaticum in the northernmost part of the peninsula, whereas E. niponica was confined to the Ohno Plain and adjacent areas in the southernmost part, and occurred mainly on C. alpicola. No thistle feeding epilachnines were found in the middle part of the peninsula despite the abundance of another thistle species, C. grayanum. Both beetle species showed lower adult preference and reduced growth performance on C. grayanum compared to their respective host plants under laboratory conditions. We concluded that the distribution of thistle feeding epilachnines in Oshima Peninsula was principally determined by the availability of appropriate host plants. 相似文献
116.
Funayama N Nakatsukasa M Kuraku S Takechi K Dohi M Iwabe N Miyata T Agata K 《Zoological science》2005,22(10):1113-1122
Sponges (phylum Porifera) have remarkable regenerative and reconstitutive abilities and represent evolutionarily the oldest metazoans. To investigate sponge stem cell differentiation, we have focused on the asexual reproductive system in the freshwater sponge Ephydatia fluviatilis. During germination, thousands of stem cells proliferate and differentiate to form a fully functional sponge. As an initial step of our investigation of stem cell (archeocyte) differentiation, we isolated molecular markers for two differentiated cell types: spicule-making sclerocyte cells, and cells involved in innate immunity. Sclerocyte lineage-specific Ef silicatein shares 45% to 62% identity with other sponge silicateins. As in situ hybridization of Ef silicatein specifically detects archeocytes possibly committed to sclerocytes, as well as sclerocytes with an immature or mature spicule, therefore covering all the developmental stages, we conclude that Ef silicatein is a suitable sclerocyte lineage marker. Ef lectin, a marker for the cell type involved in innate immunity, shares 59% to 65% identity with the marine sponge Suberites domuncula galactose-binding protein (Sd GBP) and horseshoe crab Tachypleus tridentatus tachylectin1/lectinL6. Since Sd GBP and tachylectin1 are known to bind to bacterial lipopolysaccharides and inhibit the growth of bacteria, Ef lectin may have a similar function and be expressed in a specialized type of cell involved in defense against invading bacteria. Ef lectin mRNA and protein are not expressed in early stages of development, but are detected in late stages. Therefore, Ef lectin may be specifically expressed in differentiating and/or differentiated cells. We suggest Ef lectin as a marker for cells that assume innate immunity in freshwater sponges. 相似文献
117.
Furuhata S Ando K Oki M Aoki K Ohnishi S Aoyagi K Sasaki H Sakamoto H Yoshida T Ohnami S 《Molecular and cellular biochemistry》2007,298(1-2):125-138
Among the many tissue stem or progenitor cells recently being unveiled, endothelial progenitor cells (EPCs) have attracted
particular attention, not only because of their cardinal role in vascular biology and embryology but also because of their
potential use in the therapeutic development of a variety of postnatal diseases, including cardiovascular and peripheral vascular
disorders and cancer. The aim of this study is to provide some basic and comprehensive information on gene expression of EPCs
to characterize the cells in molecular terms. Here, we focus on EPCs derived from CD34-positive mononuclear cells of human
umbilical cord blood. The EPCs were purified and expanded in culture and analyzed by a high-density oligonucleotide microarray
and real-time RT-PCR analysis. We identified 169 up-regulated and 107 down-regulated genes in the EPCs compared with three
differentiated endothelial cells of human umbilical vein endothelial cells (HUVEC), human lung microvascular endothelial cells
(LMEC) and human aortic endothelial cells (AoEC). It is expected that the obtained list include key genes which are critical
for EPC function and survival and thus potential targets of EPC recognition in vivo and therapeutic modulation of vasculogenesis
in cancer as well as other diseases, in which de novo vasculogenesis plays a crucial role. For instance, the list includes
Syk and galectin-3, which encode protein tyrosine kinase and β-galactoside-binding protein, respectively, and are expressed higher in EPCs than
the three control endothelial cells. In situ hybridization showed that the genes were expressed in isolated cells in the fetal
liver at E11.5 and E14.5 of mouse development. 相似文献
118.
119.
Masaya Sakamoto Rimei Nishimura Taiga Irako Daisuke Tsujino Kiyotaka Ando Kazunori Utsunomiya 《Cardiovascular diabetology》2012,11(1):1-7
Background
The role of Lipoprotein (a) cholesterol {Lp(a)-C}as an additional and/or independent risk factor for cardiovascular disease (CVD) is not clear. We evaluated the associations between Lp(a)-C and other CVD risk factors including plasma lipoprotein concentrations and body fatness in overweight and obese African American children.Methods
A cross-sectional analysis was carried out using data from a sample of 121 African American children aged 9-11 years with Body Mass Index (BMI)'s greater than the 85th percentile. Body height, weight and waist circumference (WC) were measured. Fasting plasma concentrations of Lp(a)-C, Total cholesterol (TC), High density lipoprotein cholesterol (HDL-C), Very low density lipoprotein cholesterol (VLDL-C), Intermediate density lipoprotein cholesterol (IDL-C), Low density lipoprotein cholesterol (LDL-C), and Triacylglycerides (TAG) were analyzed using the vertical auto profile (VAP) cholesterol method.Results
After adjusting for child age, gender, and pubertal status, Lp(a)-C was positively associated with both HDL-C and TC, and negatively associated with VLDL-C and TAG. Including BMIz and WC as additional covariates did not alter the direction of the relationships between Lp(a)-C and the other lipoproteins. Finally, after adjusting for the other plasma lipoproteins, Lp(a)-C remained strongly associated with HDL-C, whereas the associations of Lp(a)-C with the other lipoproteins were not significant when HDL-C was simultaneously included in the regression models.Conclusions
Lp(a)-C was positively associated with HDL-C and this association is not influenced by other lipoprotein subclasses or by the degree of obesity. We conclude that Lp(a) cholesterol is not an independent risk factor for CVD in African American children. 相似文献120.
Phylogenetic analysis of the human gut microbiota using 16S rDNA clone libraries and strictly anaerobic culture-based methods 总被引:21,自引:0,他引:21
The human gut microbiota from three healthy subjects were compared by the use of a sequence analysis of 16S rDNA libraries and a culture-based method. Direct counts ranged from 1.9 X 10" to 4.0 X 10" cells/g (wet weight), and plate counts totaled 6.6 X 10(10) to 1.2 X 10(11) CFU/g (wet weight). Sixty to seventy percent of the bacteria in the human intestinal tract cannot be cultured with currently available methods. The 16S rDNA libraries from three subjects were generated from total community DNA in the intestinal tract with universal primer sets. Randomly selected clones were partially sequenced. All purified colonies detected from the surface of the agar plate were used for a partial sequencing of 16S rDNA. On the basis of sequence similarities, the clones and colonies were classified into several clusters corresponding to the major phylum of the domain Bacteria. Among a total of 744 clones obtained, approximately 25% of them belonged to 31 known species. About 75% of the remaining clones were novel "phylotypes" (at least 98% similarity of clone sequence). The predominant intestinal microbial community consisted of 130 species or phylotypes according to the sequence data in this study. The 16S rDNA libraries and colonies included the Bacteroides group, Streptococcus group, Bifidobacterium group, and Clostridium rRNA clusters IV, IX, XIVa, and XVIII. Moreover, several previously uncharacterized and uncultured microorganisms were recognized in clone libraries and colonies. Our results also showed marked individual differences in the composition of intestinal microbiota. 相似文献