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991.
The MuS1 gene is highly homologous to many stress-related proteins in plants. Here, we characterized whether a new candidate gene, MuS1, is related to multiple stress tolerance in yeast as it is in plants. Transgenic yeast strain expressing MuS1 were more resistant to hydrogen peroxide, menadione, high salinity, metals (i.e., cadmium, copper, iron, and zinc), ethanol, and lactic acid than wild-type strain transformed with a vector alone. In addition, the alcohol yield of the transgenic yeast strain was higher than that of the wild-type strain during the batch fermentation process. These results show that MuS1-expressing transgenic yeast strain exhibits enhanced alcohol yield as well as tolerance to abiotic stresses, especially metal stress. 相似文献
992.
Song MS Moon HJ Kwon HI Pascua PN Lee JH Baek YH Woo KJ Choi J Lee S Yoo H Oh I Yoon Y Rho JB Sung MH Hong SP Kim CJ Choi YK 《Journal of microbiology (Seoul, Korea)》2012,50(3):478-488
The threat of a highly pathogenic avian influenza (HPAI) H5N1 virus causing the next pandemic remains a major concern. In this study, we evaluated the immunogenicity and efficacy of an inactivated whole-virus H5N1 pre-pandemic vaccine (MG1109) formulated by Green Cross Co., Ltd containing the hemagglutinin (HA) and neuraminidase (NA) genes of the clade 1 A/Vietnam/1194/04 virus in the backbone of A/Puerto Rico/8/34 (RgVietNam/04xPR8/34). Administration of the MG1109 vaccine (2-doses) in mice and ferrets elicited high HI and SN titers in a dose-dependent manner against the homologous (RgVietNam/04xPR8/34) and various heterologous H5N1 strains, (RgKor/W149/06xPR8/34, RgCambodia/04xPR8/34, RgGuangxi/05xPR8/34), including a heterosubtypic H5N2 (A/Aquatic bird/orea/W81/05) virus. However, efficient cross-reactivity was not observed against heterosubtypic H9N2 (A/Ck/Korea/H0802/08) and H1N1 (PR/8/34) viruses. Mice immunized with 1.9 μg HA/dose of MG1109 were completely protected from lethal challenge with heterologous wild-type HPAI H5N1 A/EM/Korea/W149/06 (clade 2.2) and mouse-adapted H5N2 viruses. Furthermore, ferrets administered at least 3.8 μg HA/dose efficiently suppressed virus growth in the upper respiratory tract and lungs. Vaccinated mice and ferrets also demonstrated attenuation of clinical disease signs and limited virus spread to other organs. Thus, this vaccine provided immunogenic responses in mouse and ferret models even against challenge with heterologous HPAI H5N1 and H5N2 viruses. Since the specific strain of HPAI H5N1 virus that would potentially cause the next outbreak is unknown, pre-pandemic vaccine preparation that could provide cross-protection against various H5 strains could be a useful approach in the selection of promising candidate vaccines in the future. 相似文献
993.
Bo Yeon Kim Kwang Sik Lee Mi Ri Sohn Soo Dong Woo Sung Sik Yoo Yeon Ho Je Byung Rae Jin 《Journal of Asia》2012,15(1):114-120
The expression of viral antigens in baculovirus-infected insect cells is often ineffective. As an alternative approach, therefore, we developed the recombinant polyhedra technology, which is an efficient strategy for the production of viral subunit vaccine. Here, we report a strategy for the large-scale production of a pseudorabies virus (PRV) gB or gC in the larvae of a baculovirus-infected silkworm, Bombyx mori. We constructed a recombinant B. mori nucleopolyhedrovirus (BmNPV) that expressed recombinant polyhedra together with the epitope regions of PRV gB or heparin-binding domains of PRV gC. Recombinant BmNPV-PRV-gB or BmNPV-PRV-gC-infected silkworm larvae expressed native polyhedrin and fusion protein that was detected using both anti-polyhedrin and anti-PRV gB or anti-PRV-gC antibodies. Electron and confocal microscopy demonstrated that the recombinant polyhedra contained both the fusion protein and native polyhedrin with a normal morphology and that the recombinant polyhedra contained PRV gB or gC. The yield of gB or gC antigen produced in BmNPV-PRV-gB or BmNPV-PRV-gC-infected silkworm larvae reached 0.69 or 0.46 mg per larva, respectively, at 6 days post-infection. These results demonstrate that the recombinant polyhedra strategy can be used for the large-scale production of PRV gB or gC antigen. 相似文献
994.
The oriental fruit moth, Grapholita molesta, is becoming a large threat to Korean pear production. Timely management of the egg and early larval stages from the spring emergence is critical to reduce the G. molesta population during the pear growing season. A model was developed to precisely predict the spring occurrence of G. molesta adults as a function of accumulated degree-days. The model was validated with male moth caught in sex pheromone-baited traps placed in pear orchards at two major pear production regions (Icheon and Naju) of Korea in 2010. We applied nine distribution models to describe the cumulative proportions of G. molesta males caught relative to accumulated degree-days. The observed phenology of the G. molesta spring population was well described by the nine models. The predicted dates for the cumulative 50% male moth catches were within a 5 day period. Based on statistical information criteria (Akaike's and Bayes–Schwartz information criteria), we recommend the sigmoid function referred by Brown and Mayer, because of its ease of use and meaningfulness; the parameter “b” denotes the degree-day accumulation at 50% moth emergence. The G. molesta spring emergence model could be applied to determine optimal chemical treatment timing for controlling G. molesta in fruit tree orchards and further help to develop a full-cycle phenology model of G. molesta. 相似文献
995.
996.
Jae-Hyun Park Sookyung Ryoo Suk Jae Kim Gyeong-Moon Kim Chin-Sang Chung Kwang Ho Lee Oh Young Bang 《PloS one》2012,7(9)
Background
Leukoaraiosis and cerebral microbleeds (CMB), which represent cerebral microangiopathy, commonly coexist in patients with acute lacunar stroke. Since they may have different impacts on stroke prognosis and treatment, it is important to know the factors associated with leukoaraiosis-predominant vs. CMB-predominant microangiopathies.Methods
We prospectively recruited 226 patients with acute lacunar infarction and divided them into four groups according to the Fazekas’ score and the presence of CMB: mild, red (predominant CMB), white (predominant leukoaraiosis) and severe microangiopathy groups. For comparison, we also evaluated 50 patients with intracerebral hemorrhage (ICH). We evaluated the clinical and laboratory findings of microangiopathy subtypes in patients with acute lacunar stroke and then compared them with those of primary ICH.Results
The risk factor profile was different among the groups. Patients with acute lacunar infarct but mild microangiopathy were younger, predominantly male, less hypertensive, and more frequently had smoking and heavy alcohol habits than other groups. The risk factor profile of red microangiopathy was similar to that of ICH but differed from that of white microangiopathy. The subjects in the white microangiopathy group were older and more frequently had diabetes than those in the red microangiopathy or ICH group. After adjustments for other factors, age [odds ratio (OR) 1.13; 95% confidence interval (CI) 1.08–1.18; p<0.001] and diabetes (OR 2.28; 95% CI 1.02–5.13; p = 0.045) were independently associated with white microangiopathy, and age (OR 1.05; 95% CI 1.01–1.08; p = 0.010) was independent predictor for red microangiopathy compared to mild microangiopathy.Conclusion
Patients with acute lacunar infarction have a different risk factor profile depending on microangiopathic findings. Our results indicate that diabetes may be an one of determinants of white (leukoaraiosis-predominant) microangiopathy, whereas smoking and alcohol habits in relatively young people may be a determinants of mild microangiopahic changes in patients with lacunar infarction. 相似文献997.
Jung Hwan Kim Kyung Won Shim Yeong Sook Yoon Sang Yeoup Lee Sung Soo Kim Sang Woo Oh 《PloS one》2012,7(9)
Background
Cigarette smoking and obesity are leading public health concerns. Both increase the risk for cardiovascular disease, cancer, and metabolic abnormalities. This study was conducted to assess the association between cigarette smoking and different types of obesity.Methodology/Principal Findings
Two hundred eighty-three visitors to university hospitals located in four main provinces of South Korea were participated. All participants were classified as either current/past or never smokers and were divided into quartiles according to the total pack-years. Body mass index, waist circumference, total body fat percentage, and area of visceral and abdominal subcutaneous fat were measured. These results of each groups were compared. Waist circumference, and visceral fat area showed a J- or U-shaped association with total smoking amount during a lifetime. After restricting the analyses to past/current smokers, we found significant dose-dependent associations of smoking pack-years with abdominal and visceral obesity. Overall obesity measured by body mass index and total body fat percentage did not show such associations. Although current smokers clearly showed significant associations, we could not demonstrate these in past smokers, possibly because of the limited sample size.Conclusions/Significance
Although smokers did not show significant difference in mean body mass index than those who never smoked, they showed more metabolically adverse fat distributions with increasing smoking amounts. This finding suggests that smoking is not beneficial for weight control. Therefore, smoking cessation and avoidance of smoking commencement should be addressed as important public health issues in preventing obesity and related complications. 相似文献998.
The multifunctional regulator VelB physically interacts with other velvet regulators and the resulting complexes govern development and secondary metabolism in the filamentous fungus Aspergillus nidulans. Here, we further characterize VelB’s role in governing asexual development and conidiogenesis in A. nidulans. In asexual spore formation, velB deletion strains show reduced number of conidia, and decreased and delayed mRNA accumulation of the key asexual regulatory genes brlA, abaA, and vosA. Overexpression of velB induces a two-fold increase of asexual spore production compared to wild type. Furthermore, the velB deletion mutant exhibits increased conidial germination rates in the presence of glucose, and rapid germination of conidia in the absence of external carbon sources. In vivo immuno-pull-down analyses reveal that VelB primarily interacts with VosA in both asexual and sexual spores, and VelB and VosA play an inter-dependent role in spore viability, focal trehalose biogenesis and control of conidial germination. Genetic and in vitro studies reveal that AbaA positively regulates velB and vosA mRNA expression during sporogenesis, and directly binds to the promoters of velB and vosA. In summary, VelB acts as a positive regulator of asexual development and regulates spore maturation, focal trehalose biogenesis and germination by interacting with VosA in A. nidulans. 相似文献
999.
Yone J. Yoon Sheryl L. White Xianglian Ni Alexander P. Gokin Miguel Martin-Caraballo 《PloS one》2012,7(11)
AMPA receptors lacking the GluA2 subunit allow a significant influx of Ca2+ ions. Although Ca2+-permeable AMPA receptors are a familiar feature at early stages of development, the functional significance of these receptors during the maturation of the nervous system remains to be established. Chicken lumbar motoneurons express Ca2+-permeable AMPA receptors at E6 but the Ca2+ permeability of AMPA receptors decreases ∼3-fold by E11. Considering that activity-dependent changes in intracellular Ca2+ regulates dendritic outgrowth, in this study we investigated whether downregulation of GluA2 expression during a critical period of development alters the dendritic arborization of spinal motoneurons in ovo. We use an avian replication-competent retroviral vector RCASBP (B) carrying the marker red fluorescent protein (RFP) and a GluA2 RNAi construct to downregulate GluA2 expression. Chicken embryos were infected at E2 with one of the following constructs: RCASBP(B)-RFP, RCASBP(B)-RFP-scrambled RNAi, or RCASBP(B)-RFP-GluA2 RNAi. Infection of chicken embryos at E2 resulted in widespread expression of RFP throughout the spinal cord with ≥60% of Islet1/2-positive motoneurons infected, resulting in a significant reduction in GluA2 protein expression. Downregulation of GluA2 expression had no effect on the dendritic arborization of E6 motoneurons. However, downregulation of GluA2 expression caused a significant reduction in the dendritic arborization of E11 motoneurons. Neither motoneuron survival nor maturation of network activity was affected by changes in GluA2 expression. These findings demonstrate that increased GluA2 expression and changes in the Ca2+ permeability of AMPA receptors regulate the dendritic arborization of spinal cord motoneurons during a critical period of development. 相似文献
1000.
Young Eun Chon Eun Hee Choi Ki Jun Song Jun Yong Park Do Young Kim Kwang-Hyub Han Chae Yoon Chon Sang Hoon Ahn Seung Up Kim 《PloS one》2012,7(9)