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21.
Kung Ahn Jin-Han Bae Kyu-Hwi Nam Chong-Eon Lee Kyung-Do Park Hak-Kyo Lee Byung-Wook Cho Heui-Soo Kim 《Genes & genomics.》2011,33(3):245-250
Quantitative analysis of horse gene expression profiles under diverse experimental conditions is limited by the lack of reliable reference genes for normalization of mRNA levels. Therefore, in this study, the expression of potential reference genes was compared between thoroughbred and Jeju native horse (Jeju pony). We compared the expression of nine genes by quantitative real-time RT-PCR in fourteen tissues between the two horse breeds and analyzed their stability using the geNorm and NormFinder programs. The data obtained in this study suggest that the UBB gene could serve as a reference gene in gene expression analysis of thoroughbred and Jeju native horses. 相似文献
22.
Wild species are valued as a unique source of genetic variation, but they have rarely been used for the genetic improvement of quantitative traits. To identify trait-improving quantitative trait loci (QTL) alleles from exotic species, an accession of Oryza rufipogon, a relative of cultivated rice, was chosen on the basis of a genetic diversity study. An interspecific BC2 testcross population (V20A/O. rufipogon//V20B///V20B////Ce64) consisting of 300 families was evaluated for 12 agronomically important quantitative traits. The O. rufipogon accession was phenotypically inferior for all 12 traits. However, transgressive segregants that outperformed the original elite hybrid variety, V20A/Ce64, were observed for all traits examined. A set of 122 RFLP and microsatellite markers was used to identify QTL. A total of 68 significant QTL were identified, and of these, 35 (51%) had beneficial alleles derived from the phenotypically inferior O. rufipogon parent. Nineteen (54%) of these beneficial QTL alleles were free of deleterious effects on other characters. O. rufipogon alleles at two QTL on chromosomes 1 and 2 were associated with an 18 and 17% increase in grain yield per plant, respectively, without delaying maturity or increasing plant height. This discovery suggests that the innovative use of molecular maps and markers can alter the way geneticists utilize wild and exotic germplasm. 相似文献
23.
Kil-Yoon Kang Dong-Hyun Ahn Sun-Mi Jung Dong-Hun Kim Byung-Soo Chun 《Biotechnology and Bioprocess Engineering》2005,10(4):315-321
Supercritical carbon dioxide extraction was investigated as a method for removing lipids and bad flavor from tuna viscera.
To find the optimum conditions, different experimental variables, such as pressure, temperature, flow rate of solvent and
sample size, were evaluated for the effective removal of lipids and the undesirable smell. Ethanol was used as the entrainer,
with a 3% by vol CO2 flow rate. By increasing the pressure at constant temperature, the efficiency of the lipid removal was improved and the protein
was concentrated without denaturalization. The main fatty acids extracted from the tuna viscera were palmitic acid (16∶0),
heptadecanoic acid (17∶1), oleic acid (18∶1) and docosahexaenoic acid (22∶6). The major amino acids in the tuna viscera treated
by supercritical carbon dioxide were glutamic acid, leucine and lysine, and the free amino acids werel-proline, taurine andl-α-aminoadipic acid. 相似文献
24.
Molecular interactions in ribose transport: the binding protein module symmetrically associates with the homodimeric membrane transporter. 下载免费PDF全文
The Escherichia coli high-affinity ribose transporter is composed of the periplasmic ribose-binding protein (RBP or RbsB), the membrane component (RbsC) and the ATP-binding protein (RbsA). In order to dissect the molecular interactions initiating the transport process, RbsC suppressors for transport-defective rbsB mutations were isolated. These suppressors are localized in two regions of RbsC, which are allele-specific to N- or C-terminal domain mutations of RBP, suggesting that there are two distinct regions of RbsC, each interacting with one of the two domains of RBP. To demonstrate that these two regions provide a homodimeric binding surface for RBP we constructed a dimeric rbsC in which two genes are joined tandemly from head to tail with the addition of a linker. The dimeric RbsC protein is stable and functional in growth and ribose uptake. By exploiting the allele specificity between the domain-specific mutations and their suppressors, we generated all mutation-suppressor combinations in a single rbsB plus the dimeric rbsC genes. Their phenotypes are consistent with the proposal that the binding protein module interacts symmetrically with homodimeric RbsC. The mode of association proposed here for the ribose transport components could be extended to other ABC transporters with similar structural organizations. 相似文献
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26.
Purpose
To investigate whether corneal thickness parameters measured by optical coherence tomography (OCT), such as central corneal thickness (CCT), central corneal stromal thickness (CCST), and central corneal epithelial thickness (CCET), influence the intraocular pressure (IOP) difference measured by Goldmann applanation tonometry (GAT) and non-contact tonometry (NCT).Methods
In total, 50 eyes from 50 subjects without glaucomatous defects were included in this retrospective, cross-sectional study. We measured IOP using GAT and NCT and calculated the difference between the two methods. CCT was measured by a Cirrus HD-OCT device using anterior segment imaging. The basement membrane of the epithelium, which was seen as a high-reflection line in the OCT image, was taken as a reference line to measure CCST and CCET.Results
The mean IOP measured by GAT and NCT was 16.7 ± 3.0 and 18.1 ± 3.8 mmHg, respectively. The mean IOP difference was 1.5 ± 1.7 mmHg, and the IOP measured by NCT was 8.4% ± 11.3% higher than that measured by GAT. The CCET and CCST were 57.9 ± 5.6 and 501.7 ± 33.8 μm, respectively. CCT showed a positive correlation with both GAT IOP (r = 0.648, P < 0.001) and NCT IOP (r = 0.676, P < 0.001). Although CCST showed a significant correlation with GAT IOP and NCT IOP, CCET did not. The difference between GAT IOP and NCT IOP increased with CCT (r = 0.333, P = 0.018), and CCET was positively correlated with the IOP difference between GAT and NCT (r = 0.435, P = 0.002).Conclusions
IOP increased with greater CCT, and CCST seemed to have a more important role than CCET. CCET also increased with greater CCT, and this may be a possible explanation for the increasing difference in IOP between GAT and NCT with increasing CCT. 相似文献27.
28.
Numerous recent reports suggest that statins (hydroxy-3-methylglutaryl-CoA reductase inhibitors) exhibit potential to suppress tumorigenesis through a mechanism that is not fully understood. Therefore, in this article, we investigated the effects of simvastatin on TNF-alpha-induced cell signaling. We found that simvastatin potentiated the apoptosis induced by TNF-alpha as indicated by intracellular esterase activity, caspase activation, TUNEL, and annexin V staining. This effect of simvastatin correlated with down-regulation of various gene products that mediate cell proliferation (cyclin D1 and cyclooxygenase-2), cell survival (Bcl-2, Bcl-x(L), cellular FLIP, inhibitor of apoptosis protein 1, inhibitor of apoptosis protein 2, and survivin), invasion (matrix mellatoproteinase-9 and ICAM-1), and angiogenesis (vascular endothelial growth factor); all known to be regulated by the NF-kappaB. We found that simvastatin inhibited TNF-alpha-induced NF-kappaB activation, and l-mevalonate reversed the suppressive effect, indicating the role of hydroxy-3-methylglutaryl-CoA reductase. Simvastatin suppressed not only the inducible but also the constitutive NF-kappaB activation. Simvastatin inhibited TNF-alpha-induced IkappaBalpha kinase activation, which led to inhibition of IkappaBalpha phosphorylation and degradation, suppression of p65 phosphorylation, and translocation to the nucleus. NF-kappaB-dependent reporter gene expression induced by TNF-alpha, TNFR1, TNFR-associated death domain protein, TNFR-associated factor 2, TGF-beta-activated kinase 1, receptor-interacting protein, NF-kappaB-inducing kinase, and IkappaB kinase beta was abolished by simvastatin. Overall, our results provide novel insight into the role of simvastatin in potentially preventing and treating cancer through modulation of IkappaB kinase and NF-kappaB-regulated gene products. 相似文献
29.
Hyun-Ju Kim Cheol-Su Park Siwon Lee Tae-Young Ahn 《Journal of microbiology (Seoul, Korea)》2014,52(7):554-558
A novel bacterial strain, designated PFS-5T, was isolated from the soil environment with feces of a live poultry farm located in Cheonan, Republic of Korea. Strain PFS-5T was Gram-staining-positive, motile, strictly aerobic bacterium, rod-shaped, and endospore-forming. The strain contained meso-diaminopimelic acid in their peptidoglycan and MK-7 menaquinone. The major fatty acids were anteiso-C15:0 (44.2%), C16:0 (22.2%), and iso-C15:0 (16.7%). The DNA G+C content was 40.1 mol%. Comparative 16S rRNA gene sequence analysis identified strain PFS-5T in the genus Bacillus, exhibiting the highest level of sequence similarity with type strain of B. herbersteinensis D-1,5aT (96.9%), B. humi LMG 22167T (96.7%), B. alkalitelluris BA288T (96.1%), B. litoralis SW-211T (96.0%), and B. luteolus YIM93174T (95.5%). The major polar lipids of PFS-5T were diphosphatidylglycerol and phosphatidylglycerol. On the basis of result from poly-phasic data, strain PFS-5T represents a novel species, for which the name Bacillus cheonanensis sp. nov. is proposed (Type strai PFS-5T = KACC 17469T = JCM19333T). 相似文献
30.