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81.
Both the role and source of tumor necrosis factor (TNF-alpha) in lipopolysaccharide (LPS)-induced nasal inflammation were investigated using TNF-alpha gene deficient (TNF-alpha -/-) mice and chimeric mice that are TNF-alpha gene deficient only in bone marrow-derived cells. In the present study, intracellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) mRNA expression levels in the nasal mucosa were significantly decreased following intranasal instillation of LPS in TNF-alpha gene deficient mice compared to those in wild type mice. In contrast, ICAM-1 and VCAM-1 mRNA expressions were not significantly decreased although TNF-alpha mRNA expression was dramatically decreased in TNF-alpha gene deficient bone marrow-transplanted-chimeric (TNF-alpha -/--->+/+) mice compared to those in wild type bone marrow-transplanted-control (TNF-alpha +/+-->+/+) mice. These results indicate that the elevation of TNF-alpha mRNA in the nasal mucosa is mainly originated from bone marrow-derived cells. However, even low expression of TNF-alpha at local inflammation sites is sufficient to induce the expression of adhesion molecules in acute LPS-induced experimental rhinitis. 相似文献
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83.
We conducted a polymerase chain reaction--restriction fragment length polymorphism (PCR-RFLP) analysis of the mitochondrial cytochrome b gene to elucidate the detailed genetic population structure of Japanese wild populations of medaka, Oryzias latipes. The analysis of 1,225 specimens collected from 303 sites identified 67 mitotypes. Subsequently we determined the nucleotide sequences of the complete cytochrome b gene (1141-bp) to clarify the phylogenetic relationships among mitotypes. The phylogenetic tree based on nucleotide sequences indicated three major clades (A, B and C) that differed by 11.3-11.8%, corresponding to three clusters previously identified by RFLP analysis of entire mitochondrial DNAs. The geographic distribution of mitotypes in clades A and B was fully concordant with the Northern and Southern Populations defined by allozymes. Clade A could be subdivided into three subclades and clade B into eleven, with sequence divergences among subclades of 1.3-5.8%. Each distribution of mitotypes in subclades roughly corresponded to that of mtDNA haplotypes in subclusters previously identified. Mitotypes in clade C were found only in the Kanto district. The phylogenetic relationships and the estimated divergence times suggest that three Japanese clades originated from a common ancestor and were separated during the Pliocene, and that the regional differentiation of subclades was closely connected with the geological history of the Quaternary. This study has also demonstrated the possibility of artificial disturbance of natural distribution especially in the Kanto district and the superior efficacy of PCR-RFLP analysis as a simple method for detecting genetic variation and artificial gene flow of medaka. 相似文献
84.
Hirota M Shimizu Y Kamo T Makabe H Shibata H 《Bioscience, biotechnology, and biochemistry》2003,67(7):1597-1600
Three new plant growth regulatory sesquiterpenoids were isolated from the Lactarius repraesentaneus fungus. Their structures were elucidated to be a protoilludene sesquiterpene, namely repraesentin A (1), and two related sesquiterpenes, namely repraesentins B (2) and C (3). Compounds 1-3 showed promotion activities toward the radicle elongation of lettuce seedlings by 136%, 118% and 184% at 67 ppm, respectively. 相似文献
85.
Fractionation of sugarcane bagasse by hydrothermal treatment 总被引:1,自引:0,他引:1
Hydrothermal treatment of sugarcane bagasse was conducted using a semi-batch reactor to develop a new biomass fractionation method that has low impact in the environment. A continuously increasing temperature was used in this treatment. It was found that hemicellulose and lignin could be mainly extracted as a water-soluble fraction at 200-230 degrees C, while the cellulose fraction was hydrolyzed at higher temperatures (230-280 degrees C) or recovered as solid residue from this treatment. Detailed analyses of the solid residue indicated that the crystal structure and the chemical composition of the residue were in good accordance with those of untreated crystalline cellulose. These experimental and analytical findings show that this method is promising for removal of hemicellulose and lignin from woody biomass without any catalyst and organic solvent. 相似文献
86.
Evidence for recent invasion of the medaka fish genome by the Tol2 transposable element 总被引:1,自引:0,他引:1
Tol2 is a transposable element of the terminal-inverted-repeat class, residing in the genome of the medaka fish Oryzias latipes. The genus Oryzias contains more than 10 species for which phylogenetic relationships have previously been estimated. To infer the history of Tol2 in this genus we performed genomic Southern blots and PCR analyses of 10 of the species. It was revealed that Tol2 occurs in 2 of the 10 species (O. curvinotus and O. latipes) and that the length and the restriction map structure of Tol2 are identical in the two cases. Further, sequencing analysis revealed an extremely low level of divergence compared with that in a nuclear gene. These results suggest recent incorporation of Tol2 into one or both of the two species, implying horizontal transfer of Tol2 from one species to the other or into them both from a common source. 相似文献
87.
88.
The grafting of l-phenylalanine onto low molecular weight chitosan is accomplished by using carbodiimide as a coupling agent. As increase in the amount of phenylalanine in feed, the grafting chain length increases, while a number of grafting chains hardly change. The obtained product, LMWCts-g-Phe, performs sphere with an average size of ~80 nm when the % grafting is less than 123. The complexes of the LMWCts-g-Phe and DNA (LMWCts-g-Phe/DNA) prepared by a complex coacervation method possess various shapes with an average size of ~50–150 nm and a negatively charged surface. The LMWCts-g-Phe and its complex show very reduced toxicity to fibroblast cells. The release of DNA from the complex is very fast in high pH media (tris buffer, pH 8.0 and carbonate buffer, pH 9.5), and relatively slow or more sustainable in neutral and low pH ones (PBS, pH 7.4 and citric acid/trisodium citrate buffer, pH 3.0). The results suggest that the LMWCts-g-Phe be an alternative promising carrier for negatively charged active molecules. 相似文献
89.
Michele Carbone Erin G. Flores Mitsuru Emi Todd A. Johnson Tatsuhiko Tsunoda Dusty Behner Harriet Hoffman Mary Hesdorffer Masaki Nasu Andrea Napolitano Amy Powers Michael Minaai Francine Baumann Peter Bryant-Greenwood Olivia Lauk Michaela B. Kirschner Walter Weder Isabelle Opitz Harvey I. Pass Giovanni Gaudino Sandra Pastorino Haining Yang 《PLoS genetics》2015,11(12)
We recently discovered an inherited cancer syndrome caused by BRCA1-Associated Protein 1 (BAP1) germline mutations, with high incidence of mesothelioma, uveal melanoma and other cancers and very high penetrance by age 55. To identify families with the BAP1 cancer syndrome, we screened patients with family histories of multiple mesotheliomas and melanomas and/or multiple cancers. We identified four families that shared an identical BAP1 mutation: they lived across the US and did not appear to be related. By combining family histories, molecular genetics, and genealogical approaches, we uncovered a BAP1 cancer syndrome kindred of ~80,000 descendants with a core of 106 individuals, whose members descend from a couple born in Germany in the early 1700s who immigrated to North America. Their descendants spread throughout the country with mutation carriers affected by multiple malignancies. Our data show that, once a proband is identified, extended analyses of these kindreds, using genomic and genealogical studies to identify the most recent common ancestor, allow investigators to uncover additional branches of the family that may carry BAP1 mutations. Using this knowledge, we have identified new branches of this family carrying BAP1 mutations. We have also implemented early-detection strategies that help identify cancers at early-stage, when they can be cured (melanomas) or are more susceptible to therapy (MM and other malignancies). 相似文献
90.
Nanako Tokuda Mitsuru Hattori Kota Abe Yoshinori Shinohara Yusuke Nagano Takao Itino 《Ecology and evolution》2015,5(6):1271-1277
Plant–plant interspecific competition via pollinators occurs when the flowering seasons of two or more plant species overlap and the pollinator fauna is shared. Negative sexual interactions between species (reproductive interference) through improper heterospecific pollen transfer have recently been reported between native and invasive species demonstrating pollination‐driven competition. We focused on two native Impatiens species (I. noli‐tangere and I. textori) found in Japan and examined whether pollinator‐mediated plant competition occurs between them. We demonstrate that I. noli‐tangere and I. textori share the same pollination niche (i.e., flowering season, pollinator fauna, and position of pollen on the pollinator's body). In addition, heterospecific pollen grains were deposited on most stigmas of both I. noli‐tangere and I. textori flowers that were situated within 2 m of flowers of the other species resulting in depressed fruit set. Further, by hand‐pollination experiments, we show that when as few as 10% of the pollen grains are heterospecific, fruit set is decreased to less than half in both species. These results show that intensive pollinator‐mediated competition occurs between I. noli‐tangere and I. textori. This study suggests that intensive pollinator‐mediated competition occurs in the wild even when interacting species are both native and not invasive. 相似文献