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61.
Hye Jin Chung Dong Woon Lee Hee Suk Yoon Sang Myeong Lee Chung Gyoo Park Ho Yul Choo 《Journal of Asia》2010,13(4):277-282
Out of some isolated Heterorhabditis bacteriophora from Korea, ecological study on two isolates which had different geographical features was investigated. That is, effects of temperature and dose on the pathogenicity and reproduction of two Korean isolates of H. bacteriophora were investigated using Galleria mellonella larvae in the laboratory. The median lethal dose (LD50) decreased with increasing temperature, but increased at 35 °C. The optimal temperatures for infection were 30 °C for H. bacteriophora Jeju strain and 24 °C for H. bacteriophora Hamyang strain. The median lethal time, LT50 of H. bacteriophora Hamyang strain was recorded at 13 °C to 35 °C and that of H. bacteriophora Jeju strain was recorded at 18 °C to 30 °C. The number of established nematodes in G. mellonella larvae was significantly different depending on temperature and dose. When G. mellonella larvae were exposed to 300 infective juveniles (IJs), mortality of G. mellonella gradually increased with exposure time with H. bacteriophora Jeju strain but not with H. bacteriophora Hamyang strain. 87.5% mortality of G. mellonella was recorded by H. bacteriophora Hamyang strain after 1440 min whereas 100% mortality was recorded by H. bacteriophora Jeju strain after 4320 min. The time from infection to the first emergence of nematodes decreased with increasing temperature. Duration of emergence of the two strains in the White traps also decreased with increasing temperature. The highest progeny numbers of H. bacteriophora Jeju strain were 264,602 while those of H. bacteriophora Hamyang strain were 275,744 at the rate of 160 IJs at 24 °C. 相似文献
62.
Leukotactin-1-induced ERK activation is mediated via Gi/Go protein/PLC/PKC delta/Ras cascades in HOS cells 总被引:1,自引:0,他引:1
Recently cloned leukotactin-1 (Lkn-1) that belongs to CC chemokine family has not been characterized. To understand the intracellular events following Lkn-1 binding to CCR1, we investigated the activities of signaling molecules in response to Lkn-1 in human osteogenic sarcoma cells expressing CCR1. Lkn-1-stimulated cells showed elevated phosphorylation of extracellular signal-related kinases (ERK1/2) with a distinct time course. ERK activation was peaked in 30 min and 12 h showing biphasic activation of ERK. Pertussis toxin, an inhibitor of G(i)/G(o) protein, and phospholipase C (PLC) inhibitor blocked Lkn-1-induced activation of ERK. Protein kinase C delta (PKC delta) specific inhibitor rottlerin inhibited ERK activation in Lkn-1-stimulated cells. The activities of PLC and PKC delta were also enhanced by Lkn-1 stimulation. Dominant negative Ras inhibited activation of ERK. Immediate early response genes such as c-fos and c-myc were induced by Lkn-1 stimulation. Lkn-1 affected the cell cycle progression by cyclin D(3) induction. These results suggest that Lkn-1 activates the ERK pathway by transducing the signal through G(i)/G(o) protein, PLC, PKC delta and Ras, and it may play a role for cell proliferation, differentiation, and regulation of gene expression for other cellular processes. 相似文献
63.
Background
The rate of incidentally diagnosed congenital heart disease (CHD) in adulthood has not been reported. The aim of this study was to investigate the detection rate of CHD in adults by routine, general health checkups.Methods
Data was acquired from 222,401 patients older than 19?years who participated in general health checkups from January 2010 to December 2016. We excluded persons who did not undergo echocardiography during the general health checkups, who underwent echocardiography prior to the health checkups, and who were previously diagnosed with CHD.Results
Among the 27,897 patients, who were included in the final analysis, 293 cases were newly diagnosed as CHD, and the overall detection rate was 1.05%. The mean age of patients with CHD was 48.7?±?21.5?years, and most of them were female (n?=?187, 63.8%). More than two-thirds were between the third and fifth decade of life, and only six patients (2.04%) were older than 70?years. The most common type was bicuspid aortic valve (n?=?155). Interestingly, Ebstein’s anomaly that required surgical repair was detected in five persons.Conclusions
During general health checkup, there were cases of severe CHD that required cardiac surgery upon diagnosis.64.
Byung Young Park Hyunghee Lee Sangee Woo Miso Yoon Jeongjun Kim Yeonhee Hong Hee Suk Lee Eun Kyu Park Jong Cheon Hahm Jin Woo Kim Soon Shik Shin Min-Young Kim Michung Yoon 《PloS one》2015,10(11)
It has been suggested that angiogenesis modulates adipogenesis and obesity. This study was undertaken to determine whether ALS-L1023 (ALS) prepared by a two-step organic solvent fractionation from Melissa leaves, which exhibits antiangiogenic activity, can regulate adipose tissue growth. The effects of ALS on angiogenesis and extracellular matrix remodeling were measured using in vitro assays. The effects of ALS on adipose tissue growth were investigated in high fat diet-induced obese mice. ALS inhibited VEGF- and bFGF-induced endothelial cell proliferation and suppressed matrix metalloproteinase (MMP) activity in vitro. Compared to obese control mice, administration of ALS to obese mice reduced body weight gain, adipose tissue mass and adipocyte size without affecting appetite. ALS treatment decreased blood vessel density and MMP activity in adipose tissues. ALS reduced the mRNA levels of angiogenic factors (VEGF-A and FGF-2) and MMPs (MMP-2 and MMP-9), whereas ALS increased the mRNA levels of angiogenic inhibitors (TSP-1, TIMP-1, and TIMP-2) in adipose tissues. The protein levels of VEGF, MMP-2 and MMP-9 were also decreased by ALS in adipose tissue. Metabolic changes in plasma lipids, liver triglycerides, and hepatic expression of fatty acid oxidation genes occurred during ALS-induced weight loss. These results suggest that ALS, which has antiangiogenic and MMP inhibitory activities, reduces adipose tissue mass in nutritionally obese mice, demonstrating that adipose tissue growth can be regulated by angiogenesis inhibitors. 相似文献
65.
Jaroslav Červinka Martin Šálek Petr Pavluvčík Jakub Kreisinger 《Biodiversity and Conservation》2011,20(14):3459-3475
The marked negative impact of habitat fragmentation and the edge effect on many populations of bird species is a recent major
concern in conservation biology. Here, we focus on the edge effect in different sized forest patches in Central European farmland. In particular, we tested
whether the distribution of mammalian mesopredators is related to fragment size and distance to habitat edge, and whether
the contribution of these factors is additive or interactive. To assess fine-scale utilization of forest edges, we established
transects of four scent stations at different distances from forest edges into the interior (0, 25, 50, 100 m) in 146 forest
fragments of variable patch size (3.2–5099.6 ha) from May to June, 2008–2009. This large sample size allowed us to perform
detailed analyses separately for all detected species. Our findings confirm that mammalian mesopredators strongly prefer habitat
edges and small forest fragments. The probability of occurrence tended to decrease with increasing distance from the edge
for all seven carnivore species detected. The carnivores’ occurrence was also negatively correlated with forest fragment area.
All detected species tended to prefer small fragments, with the exception of the Eurasian badger (showing the reverse but
non-significant pattern) and the red fox (no effect of fragment size). In addition, the non-significant interaction between
fragment size and distance to edge suggests that both of these factors contribute independently and additively to mesopredator-mediated
effects on biota in a fragmented landscape. 相似文献
66.
Castilho A Gattinger P Grass J Jez J Pabst M Altmann F Gorfer M Strasser R Steinkellner H 《Glycobiology》2011,21(6):813-823
Glycoengineering is increasingly being recognized as a powerful tool to generate recombinant glycoproteins with a customized N-glycosylation pattern. Here, we demonstrate the modulation of the plant glycosylation pathway toward the formation of human-type bisected and branched complex N-glycans. Glycoengineered Nicotiana benthamiana lacking plant-specific N-glycosylation (i.e. β1,2-xylose and core α1,3-fucose) was used to transiently express human erythropoietin (hEPO) and human transferrin (hTF) together with modified versions of human β1,4-mannosyl-β1,4-N-acetylglucosaminyltransferase (GnTIII), α1,3-mannosyl-β1,4-N-acetylglucosaminyltransferase (GnTIV) and α1,6-mannosyl-β1,6-N-acetylglucosaminyltransferase (GnTV). hEPO was expressed as a fusion to the IgG-Fc domain (EPO-Fc) and purified via protein A affinity chromatography. Recombinant hTF was isolated from the intracellular fluid of infiltrated plant leaves. Mass spectrometry-based N-glycan analysis of hEPO and hTF revealed the quantitative formation of bisected (GnGnbi) and tri- as well as tetraantennary complex N-glycans (Gn[GnGn], [GnGn]Gn and [GnGn][GnGn]). Co-expression of GnTIII together with GnTIV and GnTV resulted in the efficient generation of bisected tetraantennary complex N-glycans. Our results show the generation of recombinant proteins with human-type N-glycosylation at great uniformity. The strategy described here provides a robust and straightforward method for producing mammalian-type N-linked glycans of defined structures on recombinant glycoproteins, which can advance glycoprotein research and accelerate the development of protein-based therapeutics. 相似文献
67.
68.
Hyun Suk Shin Na Na Kim Gyung-Suk Kil 《Marine and Freshwater Behaviour and Physiology》2013,45(4):223-238
To establish the molecular basis of circadian rhythm control by melatonin receptors (MTs), we investigated the mitochondrial ribonucleic acid (mRNA) expressions of three types of MTs in different tissues of the olive flounder (Paralichthys olivaceus). All three types of MT mRNAs were expressed in the neural tissues, while MT1 mRNA was expressed in the peripheral tissues and MT2 and MT3 mRNAs were weakly expressed or undetected in these tissues. We observed increased MT mRNA expression in the neural tissues at night under both light–dark (LD) and constant dark (DD) conditions. Although the melatonin-treated cultured pineal gland samples showed similar diurnal variations with high-MT mRNA expression levels at night compared to those of untreated cultured pineal gland samples, the expression levels were considerably higher in the melatonin-treated samples. The plasma melatonin level also significantly increased at night. Under DD conditions, the expression patterns of MT mRNAs were similar to those under the LD photocycle, but the peak was lower and the circadian change patterns were less clear. These findings reinforce the hypothesis that MTs are active in processing light information, and that these genes are regulated by the circadian clock and light, thus suggesting that MTs play an important role in daily and circadian variations in the brain and retina of olive flounders. 相似文献
69.
Summary Better production of pro-urokinase from human cell line was observed with 5% serum containing medium than 10% or serum free medium on Cytodex II under perfusion chemostat operations, showing 0.8×10–5 (IU/daycell) of maximum productivity at 0.020 (l/h) of dilution rate in 5% serum medium, which corresponds to 800 IU/mL at this dilution rate. Conversion of pro-urokinase was reduced in the serum-containing media. 相似文献
70.
Han Gil Seo Nam-Jong Paik Shi-Uk Lee Byung-Mo Oh Min Ho Chun Bum Sun Kwon Moon Suk Bang 《PloS one》2015,10(6)