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101.
Jong Seok Lee Jae Wan Wee Hye Young Lee Hyo Sil An Eock Kee Hong 《Biotechnology and Bioprocess Engineering》2010,15(3):453-459
Hericium erinaceus is a well known edible and medicinal mushroom used in East-Asia. Recently, H. erinaceus has attracted a lot of attention owing to its antitumor, immuno-modulatory, and cytotoxic effect. It has been postulated that the fruiting body of H. erinaceus contains a polysaccharide that is similar to β-D-glucan, which is known to have antitumor activity against Sarcoma 180. However, optimized liquid culture conditions for enhanced polysaccharide productivity have yet to be developed, which is a necessary step for industrial applications. Therefore, the aim of this study was to determine the optimal liquid culture conditions for maximum polysaccharide production. In shake flask cultures, the optimal concentration of ascorbic acid was found to be 2.0 g/L, which prevented the broth from changing color from yellow to black. The optimal culture conditions were determined to be 23°C, 200 rpm, and a 10% inoculum size, at an uncontrolled initial pH. In addition, the modified medium contained 20 g/L glucose, 10 g/L yeast extract, and 2.0 g/L ascorbic acid. The maximum mycelial biomass and exo-polysaccharide (EPS) production in the modified medium containing uracil was 13.43 and 1.26 g/L, respectively. 相似文献
102.
Bing Zhang Zhou Cheng Su Tong Earn Tay Vincent B. C. Tan 《Journal of molecular modeling》2010,16(6):1159-1168
In the current work, CDK5/p25 complexes were pulled apart by applying external forces with steered molecular dynamics (SMD)
simulations. The crucial interactions between the kinase and the activation protein were investigated and the SMD simulations
showed that several activation-relevant motifs of CDK5 leave p25 in sequence during the pulling and lead to an apo-CDK2 like CDK5 structure after separation. Based on systematic examination of hydrogen bond breaking and classical MD/molecular
mechanics-generalized Born/surface area) (MM-GBSA) calculations, a CDK5 activation mechanism by p25 is suggested. This is
the first step towards the systemic development of CDK inhibitors and the mechanism proposed could lead to a better understanding
of the protein–protein recognition characteristics between the kinase and its activator. 相似文献
103.
Background
Although there is a growing body of evidence showing that patients with type 2 diabetes mellitus (T2DM) have poor glycemic control in general, it is not clear whether T2DM patients with pre-existing cardiovascular diseases (CVD) are more or less likely to have good glycemic control than patients without pre-existing CVD. Our aim was to examine the degree of glycemic control among T2DM patients in Europe with and without pre-existing CVD.Methods
This is a matched cohort study based on a multi-center, observational study with retrospective medical chart reviews of T2DM patients in Spain, France, United Kingdom, Norway, Finland, Germany, and Poland. Included patients were aged >= 30 years at time of diagnosis of T2DM, had added a SU or a PPARγ agonist to failing metformin monotherapy (index date) and had pre-existing CVD (cases). A control cohort with T2DM without pre-existing CVD was identified using 1:1 propensity score matching. With difference-in-difference approach, logistic and linear regression analyses were applied to identify differences in glycemic control by CVD during the follow up period, after controlling for baseline demographics, clinical information, and concurrent anti-hyperglycemic medication use.Results
The percentage of case patients with adequate glycemic control relative to control patients during the 1st, 2nd, 3rd, and 4th years after the index date was 19.9 vs. 26.5, 16.8 vs. 26.5, 18.8 vs. 28.3, and 16.8 vs. 23.5 respectively. Cases were significantly less likely to have adequate glycemic control (odds ratio: 0.62; 95% confidence interval: 0.46-0.82) than controls after adjusting for baseline differences, secular trend, and other potential confounding covariates.Conclusions
T2DM patients with pre-existing CVD tended to have poorer glycemic control than those without pre-existing CVD, all other factors being equal. It suggests that clinicians may need to pay more attention to glycemic control among T2DM patients with CVD. 相似文献104.
105.
Multiple fluorochrome experiments with as many fluorochromes as possible are desired for exploring the detailed structure
of bioaggregates. Spectral peak interference and other practical limitations, however, restrict the maximum number of stains
used simultaneously to three. This current study proposes a sixfold labelled scheme to stain the total cells, dead cells,
proteins, lipids, and α- and β-polysaccharides in bioaggregates. Two aerobic granule systems, the phenol-fed and the acetate-fed
granules, were utilized as the testing samples for demonstrating the use of the proposed scheme. 相似文献
106.
Bioaugmentation and coexistence of two functionally similar bacterial strains in aerobic granules 总被引:2,自引:0,他引:2
The survival of the inoculated microbial culture is critical for successful bioaugmentation but impossible to predict precisely.
As an alternative strategy, bioaugmentation of a group of microorganisms may improve reliability of bioaugmentation. This
study evaluated simultaneous bioaugmentation of two functionally similar bacterial strains in aerobic granules. The two strains,
Pandoraea sp. PG-01 and Rhodococcus erythropolis PG-03, showed high phenol degradation and growth rates in phenol medium, but they were characterized as having a poor aggregation
activity and weak bioflocculant-producing and biofilm-forming abilities. In the spatially homogeneous batch conditions, strain
PG-01 with higher growth rates outcompeted strain PG-03. However, the two strains could stably coexist in the spatially heterogeneous
conditions. Then the two strains were mixed and bioaugmented into activated sludge in two sequencing batch reactors, which
were operated with the different settling times of 5 and 30 min, respectively. Aerobic granules were developed only in the
reactor with a settling time of 5 min. Fluorescence in situ hybridization and denaturing gradient gel electrophoresis showed
that the two strains could coexist in aerobic granules but not in activated sludge. These findings suggested that the compact
structure of aerobic granules provided spatial isolation for coexistence of competitively superior and inferior strains with
similar functions. 相似文献
107.
Break-induced loss of heterozygosity in fission yeast: dual roles for homologous recombination in promoting translocations and preventing de novo telomere addition
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Cullen JK Hussey SP Walker C Prudden J Wee BY Davé A Findlay JS Savory AP Humphrey TC 《Molecular and cellular biology》2007,27(21):7745-7757
Loss of heterozygosity (LOH), a causal event in tumorigenesis, frequently encompasses multiple genetic loci and whole chromosome arms. However, the mechanisms leading to such extensive LOH are poorly understood. We investigated the mechanisms of DNA double-strand break (DSB)-induced extensive LOH by screening for auxotrophic marker loss approximately 25 kb distal to an HO endonuclease break site within a nonessential minichromosome in Schizosaccharomyces pombe. Extensive break-induced LOH was infrequent, resulting from large translocations through both allelic crossovers and break-induced replication. These events required the homologous recombination (HR) genes rad32(+), rad50(+), nbs1(+), rhp51(+), rad22(+), rhp55(+), rhp54(+), and mus81(+). Surprisingly, LOH was still observed in HR mutants, which resulted predominantly from de novo telomere addition at the break site. De novo telomere addition was most frequently observed in rad22Delta and rhp55Delta backgrounds, which disrupt HR following end resection. Further, levels of de novo telomere addition, while increased in ku70Delta rhp55Delta strains, were reduced in exo1Delta rhp55Delta and an rhp55Delta strain overexpressing rhp51. These findings support a model in which HR prevents de novo telomere addition at DSBs by competing for resected ends. Together, these results suggest that the mechanisms of break-induced LOH may be predicted from the functional status of the HR machinery. 相似文献
108.
109.
Inhibition of Fc epsilon RI-mediated mast cell responses by ES-62, a product of parasitic filarial nematodes 总被引:2,自引:0,他引:2
Melendez AJ Harnett MM Pushparaj PN Wong WS Tay HK McSharry CP Harnett W 《Nature medicine》2007,13(11):1375-1381
Atopic allergy is characterized by an increase in IgE antibodies that signal through the high-affinity Fcepsilon receptor (FcepsilonRI) to induce the release of inflammatory mediators from mast cells. For unknown reasons, the prevalence of allergic diseases has recently increased steeply in the developed world. However, this increase has not been mirrored in developing countries, even though IgE concentrations are often greatly elevated in individuals from these countries, owing to nonspecific IgE induction by universally present parasitic worms. Here we offer one explanation for this paradox based on the properties of ES-62, a molecule secreted by filarial nematodes. We found that highly purified, endotoxin-free ES-62 directly inhibits the FcepsilonRI-induced release of allergy mediators from human mast cells by selectively blocking key signal transduction events, including phospholipase D-coupled, sphingosine kinase-mediated calcium mobilization and nuclear factor-kappaB activation. ES-62 mediates these effects by forming a complex with Toll-like receptor 4, which results in the sequestration of protein kinase C-alpha (PKC-alpha). This causes caveolae/lipid raft-mediated, proteasome-independent degradation of PKC-alpha, a molecule important for the coupling of FcepsilonRI to phospholipase D and mast cell activation. We also show that ES-62 is able to protect mice from mast cell-dependent hypersensitivity in the skin and lungs, indicating that it has potential as a novel therapeutic for allergy. 相似文献
110.
Two stable and water-soluble organometallic carbonyl cluster derivatives have been prepared and shown to enter the cell with ease. The CO stretching vibrations afford strong mid-infrared signals which have been demonstrated, for the first time, to be of utility in cell imaging via an IR microscope. 相似文献