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991.
A quantitative trait depends on multiple quantitative trait loci (QTL) and on the interaction between two or more QTL, named epistasis. Several methods to detect multiple QTL in various types of design have been proposed, but most of these are based on the assumption that each QTL works independently and epistasis has not been explored sufficiently. The objective of the study was to propose an integrated method to detect multiple QTL with epistases using Bayesian inference via a Markov chain Monte Carlo (MCMC) algorithm. Since the mixed inheritance model is assumed and the deterministic algorithm to calculate the probabilities of QTL genotypes is incorporated in the method, this can be applied to an outbred population such as livestock. Additionally, we treated a pair of QTL as one variable in the Reversible jump Markov chain Monte Carlo (RJMCMC) algorithm so that two QTL were able to be simultaneously added into or deleted from a model. As a result, both of the QTL can be detected, not only in cases where either of the two QTL has main effects and they have epistatic effects between each other, but also in cases where neither of the two QTL has main effects but they have epistatic effects. The method will help ascertain the complicated structure of quantitative traits. 相似文献
992.
Endo MY Suzuki R Nagahata N Hayashi N Miura A Koga S Fukuba Y 《American journal of physiology. Heart and circulatory physiology》2008,294(5):H2322-H2326
To investigate the regional hemodynamic responses of abdominal arteries at the onset of exercise and to focus on their transient responses, eight female subjects (21-30 yr) performed ergometer cycling exercise at 40 W for 4 min in a semi-supine position. Mean blood velocities (MBVs) in the right renal (RA), superior mesenteric (SMA), and splenic (SA) arteries were measured by pulsed echo-Doppler ultrasonography, with beat-by-beat measurements of heart rate (HR) and mean arterial pressure (MAP). The vascular resistance index (RI) of each artery was calculated from MBV/MAP. MAP (76 +/- 9 to 83 +/- 8 mmHg at 4 min) and HR (60 +/- 7 to 101 +/- 9 beats/min at 4 min) increased during exercise (P < 0.05). The MBV of RA and SA rapidly decreased after the onset of exercise (30 s; -19 +/- 5% and -19 +/- 12%, respectively), reaching -27 +/- 7% and -27 +/- 15% at the end of exercise (P < 0.05). RI did not change during the initial 30 s of exercise, reflecting a reduction in MAP, and increased toward the end of the exercise (+55 +/- 21% and +59 +/- 39%, respectively). In contrast, both the MBV and RI in the SMA remained constant throughout the exercise. The results indicate that, whereas the responses of renal and splenic vessels changed similarly throughout the protocol, the vascular response of SMA that mainly supplies blood to the intestinal tract was unchanged during exercise. We, therefore, conclude that low-intensity cycling exercise resulted in differential blood flow responses in arteries supplying the abdominal organs. 相似文献
993.
Electricity generation from model organic wastewater in a cassette-electrode microbial fuel cell 总被引:1,自引:0,他引:1
Shimoyama T Komukai S Yamazawa A Ueno Y Logan BE Watanabe K 《Applied microbiology and biotechnology》2008,80(2):325-330
A new highly scalable microbial fuel cell (MFC) design, consisting of a series of cassette electrodes (CE), was examined for increasing power production from organic matter in wastewater. Each CE chamber was composed of a box-shaped flat cathode (two air cathodes on both sides) sandwiched in between two proton-exchange membranes and two graphite-felt anodes. Due to the simple design of the CE-MFC, multiple cassettes can be combined to form a single unit and inserted into a tank to treat wastewater. A 12-chamber CE-MFC was tested using a synthetic wastewater containing starch, peptone, and fish extract. Stable performance was obtained after 15 days of operation in fed-batch mode, with an organic removal efficiency of 95% at an organic loading rate of 2.9 kg chemical oxygen demand (COD) per cubic meter per day and an efficiency of 93% at 5.8 kg COD per cubic meter per day. Power production was stable during this period, reaching maximum power densities of 129 W m(-3) (anode volume) and 899 mW m(-2) (anode projected area). The internal resistance of CE-MFC decreased from 2.9 (day 4) to 0.64 Omega (day 25). These results demonstrate the usefulness of the CE-MFC design for energy production and organic wastewater treatment. 相似文献
994.
Watanabe S Viet DN Kaneko J Kamio Y Yoshida S 《Bioscience, biotechnology, and biochemistry》2008,72(4):951-958
A xylanase gene, xyn1, which encodes Paenibacillus sp. strain W-61 xylanase 1 (Xyn1), was cloned in Escherichia coli. xyn1 encodes 211 amino acid residues, including 28 amino acid residues of a signal peptide. The deduced amino acid sequence of the mature Xyn1 showed 95.7%, 84.0%, and 83.7% identity to family 11 xylanases of Aeromonas caviae ME-1, Paenibacillus sp., and Bacillus stearothermophilus respectively. The physico-chemical properties of recombinant Xyn1 were very similar to those of intact Xyn1, except for the molecular mass. The pattern of xylooligosaccharides generated by rXyn1 was investigated by fluorophore-assisted carbohydrate electrophoresis (FACE). The degradation rate of xylohexaose by rXyn1 increased markedly as compared with that of xylopentaose. Xylohexaose had a single preferential point of cleavage by rXyn1. On the basis of the pattern of action of xylooligosaccharides, the number of subsites was estimated to be six. The catalytic site was located between the third and the fourth subsites from non-reducing end. 相似文献
995.
Kuramochi K Yukizawa S Ikeda S Sunoki T Arai S Matsui R Morita A Mizushina Y Sakaguchi K Sugawara F Ikekita M Kobayashi S 《Bioorganic & medicinal chemistry》2008,16(9):5039-5049
Epolactaene, isolated from cultured Penicillium sp. BM 1689-P mycelium, induces neurite outgrowth and arrests the cell cycle of the human neuroblastoma cell line, SH-SY5Y, at the G1 phase. We have found that epolactaene and its derivatives induce apoptosis in the human leukemia B-cell line, BALL-1. In this study, we prepared fluorescent and biotinylated epolactaene derivatives. We characterized the cellular location and the identification of BALL-1 proteins that reacted with these compounds. The results obtained from the reaction of epolactaene or its derivative with N-acetylcysteine methyl ester indicate that these compounds induce the disulfide formation and the -position of the epoxylactam core is the reactive site. 相似文献
996.
The aim of this research was to evaluate the use of manufacturing wallboard paper scraps as an alternative bulking agent for dairy cattle manure composting. The characteristics of the composting process were studied based on the changes in physico-chemical parameters and final compost quality. Composting of dairy cattle manure with wallboard paper was performed in a 481-L cylindrical reactor with vacuum-type aeration. Rapid degradation of organic matter was observed during the thermophilic stage of composting due to high microbial activity. High temperature and alkaline pH conditions promoted intense ammonia emission during the early stage of composting. The number of mesophilic and thermophilic microorganisms were found to be affected by changes in temperature at different composting stages. The total nitrogen (N), phosphorus (P), potassium (K), and sodium (Na) concentrations of the mixture did not change significantly after 28days of composting. However, the presence of gypsum in the paper scraps increased the calcium content of the final compost. The wallboard paper had no phyto-inhibitory effects as shown by high germination index of final compost (GI=99%). 相似文献
997.
Hattori Y Hagiwara A Ding W Maitani Y 《Bioorganic & medicinal chemistry letters》2008,18(19):5228-5232
We investigated the effect of amido- (NP-OH) and carbamate linkers (NP-HAPC) in nanoparticles composed of hydroxyethylated cationic cholesterol on siRNA transfection. The presence of NaCl in forming a NP-OH nanoplex increased the suppressive effect of gene expression by increasing the size of the nanoplex and changing the cellular uptake mechanism from membrane fusion and clathrin-mediated endocytosis to clathrin- and caveolae-mediated endocytosis. 相似文献
998.
Yoneda Y Steiniger SC Capková K Mee JM Liu Y Kaufmann GF Janda KD 《Bioorganic & medicinal chemistry letters》2008,18(5):1632-1636
Tumor targeting peptides are promising vehicles for site-directed cancer therapy. Pep42, a cyclic 13-mer oligopeptide that specifically binds to glucose-regulated protein 78 (GRP78) and internalized into cancer cells, represents an excellent vehicle for tumor cell-specific chemotherapy. Here, we report the synthesis and evaluation of Pep42-prodrug conjugates that contain a cathepsin B-cleavable linker, resulting in the traceless release of drug inside the cancer cells. 相似文献
999.
Metabolic profiling of flavonoids in Lotus japonicus using liquid chromatography Fourier transform ion cyclotron resonance mass spectrometry 总被引:1,自引:0,他引:1
Suzuki H Sasaki R Ogata Y Nakamura Y Sakurai N Kitajima M Takayama H Kanaya S Aoki K Shibata D Saito K 《Phytochemistry》2008,69(1):99-111
Flavonoids detected from a model legume plant, Lotus japonicus accessions Miyakojima MG-20 and Gifu B-129, were profiled using liquid chromatography Fourier transform ion cyclotron resonance mass spectrometry (LC-FTICR/MS). Five flavonols and two anthocyanidins were detected as aglycones. LC-FTICR/MS facilitated simultaneous detection of 61 flavonoids including compounds that have not been reported previously. Chemical information of the peaks such as retention time, lambdamax, m/z value of the quasi-molecular ion, m/z value of MS/MS fragment ions, and relative intensity of MS/MS fragments was obtained, along with the molecular formulas and conjugate structures. Fourteen were completely identified by comparison with authentic compounds. The high accuracy of m/z values, being 0.081 ppm between observed and theoretical values, allowed prediction of molecular formulas of unknown compounds with the help of isotope peak information for determination of chemical composition. Based on a predicted elemental composition, the presence of a novel nitrogen-containing flavonoid was proposed. A comparison of flavonoid profiles in flowers, stems, and leaves demonstrated that the flowers yielded the most complex profile, containing 30 flower-specific flavonoids including gossypetin glycosides and isorhamnetin glycosides. A comparison of flavonoid profiles between MG-20 and B-129 grown under the same conditions revealed that the accumulation of anthocyanins was higher in B-129 than MG-20, particularly in the stem. Developmental changes in the flavonoid profiles demonstrated that kaempferol glycosides increased promptly after germination. In contrast, quercetin glycosides, predominant flavonoids in the seeds, were not detectable in growing leaves. 相似文献
1000.
Coniferyl esters--capsiconiate and dihydrocapsiconiate--were isolated from the fruits of the pepper, Capsicum baccatum L. var. praetermissum. Their structures were determined by spectroscopic methods to be coniferyl (E)-8-methyl-6-nonenoate (capsiconiate) and coniferyl 8-methylnonanoate (dihydrocapsiconiate). This finding was further confirmed by the lipase-catalyzed condensation of coniferyl alcohol with its corresponding fatty acid derivative. The agonist activity of the esters for transient receptor potential vanilloid 1 (TRPV1) was evaluated by conducting an analysis of the intracellular calcium concentrations in TRPV1-expressing HEK293 cells. The EC50 values of capsiconiate and dihydrocapsiconiate were 3.2 and 4.2 microM, respectively. 相似文献