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121.
122.
Da Eun Lee Kyung Min Park Seung Jun Choi Jae‐Hoon Shim Pahn‐Shick Chang 《Biotechnology progress》2013,29(4):882-889
Erythorbyl laurate was continuously synthesized by esterification in a packed‐bed enzyme reactor with immobilized lipase from Candida antarctica. Response surface methodology based on a five‐level three‐factor central composite design was adopted to optimize conditions for the enzymatic esterification. The reaction variables, such as reaction temperature (10–70°C), substrate molar ratio ([lauric acid]/[erythorbic acid], 5–15), and residence time (8–40 min) were evaluated and their optimum conditions were found to be 56.2°C, 14.3, and 24.2 min, respectively. Under the optimum conditions, the molar conversion yield was 83.4%, which was not significantly different (P < 0.05) from the value predicted (84.4%). Especially, continuous water removal by adsorption on an ion‐exchange resin in a packed‐bed enzyme reactor improved operational stability, resulting in prolongation of half‐life (2.02 times longer compared to the control without water‐removal system). Furthermore, in the case of batch‐type reactor, it exhibited significant increase in initial velocity of molar conversion from 1.58% to 2.04%/min. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29:882–889, 2013 相似文献
123.
Yun-Sung Choi Yong-Min Kim Ok-Jin Hwang Yun-Jeong Han Soo Young Kim Jeong-Il Kim 《Plant biotechnology reports》2013,7(2):165-173
The Arabidopsis, abscisic acid responsive element-binding factor 3, ABF3 is known to play an important role in stress responses via regulating the expression of stress-responsive genes. In this study, we introduced pCAMBIA3301 vector harboring the ABF3 gene into creeping bentgrass (Agrostis stolonifera) through Agrobacterium-mediated transformation in order to develop a stress-tolerant variety of turfgrass. After transformation, putative transgenic plants were selected using the herbicide resistance assay. Genomic integration of the transgene was confirmed by genomic PCR and Southern blot analysis, and gene expression was validated by northern blot analysis. Under drought-stressed condition, the transgenic plants overexpressing ABF3 displayed significantly enhanced drought tolerance with higher water content and slower water loss rate than the control plants. Furthermore, the stomata of the ABF3 transgenic plants closed more than those of wild-type creeping bentgrass plants, under both non-stressed and ABA treatment conditions. In addition, the transgenic plants showed enhanced tolerance to heat stress. These results suggest that the overexpression of the ABF3 gene in creeping bentgrass might enhance survival in water-limiting and high temperature environments through increased stomatal closure and reduced water losses. 相似文献
124.
Jong-Min Lim Joon-Woo Ahn Kwon Hwangbo Dong-Woog Choi Eun-Jeong Park Mi Sook Hwang Jang Ryol Liu Won-Joong Jeong 《Plant biotechnology reports》2013,7(3):407-414
Various fluorescent proteins have been developed for in vivo reporter systems in diverse prokaryotes and eukaryotes. However, few in vivo imaging systems have been reported for the model algae Chlamydomonas reinhardtii or Pyropia sp. In this study, an effective imaging system using cyan fluorescent protein (CFP) was developed for the green alga C. reinhardtii, and its application was also successful in the red macroalgae Pyropia tenera and P. yezoensis. For optimization of CFP expression in C. reinhardtii and Pyropia sp., we modified codon usage in the CFP gene (CFP), generating PtCrCFP (Pyropia tenera/Chlamydomonas reinhardtii CFP). PtCrCFP was successfully expressed in PtCrCFP-expressing UVM11 transgenic lines, and high accumulation levels of PtCrCFP were found by western blotting. Consistent with these results, PtCrCFP fluorescence was clearly detected with a low level of chlorophyll background fluorescence in PtCrCFP-expressing UVM11 transgenic lines. In Pyropia sp. gametophytic cells, transient expression of PtCrCFP fluorescence was distinctly visualized. PtCrCFP fluorescence was also observed during the regeneration of monospores and young gametophytes from PtCrCFP-expressing P. yezoensis gametophytic cells. These results suggest that PtCrCFP may be useful as an in vivo reporter in green algae due to the short emission wavelength of CFP, which provides a low level of chlorophyll background fluorescence. This study also presents the possibility of PtCrCFP’s use as a visible selection marker for the generation of transgenic lines in the red algae Pyropia sp. Thus, PtCrCFP as an in vivo visualization tool may offer new opportunities for the functional analysis of genetic studies in both green and red algae. 相似文献
125.
Min Kwon Joon-Yeop Lee Wang-Youn Won Jae-Woo Park Jung-Ah Min Changtae Hahn Xinyu Gu Ji-Hye Choi Dai-Jin Kim 《PloS one》2013,8(2)
Objective
The aim of this study was to develop a self-diagnostic scale that could distinguish smartphone addicts based on the Korean self-diagnostic program for Internet addiction (K-scale) and the smartphone''s own features. In addition, the reliability and validity of the smartphone addiction scale (SAS) was demonstrated.Methods
A total of 197 participants were selected from Nov. 2011 to Jan. 2012 to accomplish a set of questionnaires, including SAS, K-scale, modified Kimberly Young Internet addiction test (Y-scale), visual analogue scale (VAS), and substance dependence and abuse diagnosis of DSM-IV. There were 64 males and 133 females, with ages ranging from 18 to 53 years (M = 26.06; SD = 5.96). Factor analysis, internal-consistency test, t-test, ANOVA, and correlation analysis were conducted to verify the reliability and validity of SAS.Results
Based on the factor analysis results, the subscale “disturbance of reality testing” was removed, and six factors were left. The internal consistency and concurrent validity of SAS were verified (Cronbach''s alpha = 0.967). SAS and its subscales were significantly correlated with K-scale and Y-scale. The VAS of each factor also showed a significant correlation with each subscale. In addition, differences were found in the job (p<0.05), education (p<0.05), and self-reported smartphone addiction scores (p<0.001) in SAS.Conclusions
This study developed the first scale of the smartphone addiction aspect of the diagnostic manual. This scale was proven to be relatively reliable and valid. 相似文献126.
Jihye Han Joonbeom Bae Chang-Yong Choi Sang-Pil Choi Hyung-Sik Kang Eun-Kyeong Jo 《Autophagy》2016,12(12):2326-2343
Severe hepatic inflammation is a common cause of acute or chronic liver disease. Macrophages are one of the key mediators which regulate the progress of hepatic inflammation. Increasing evidence shows that the TAM (TYRO3, AXL and MERTK) family of RTKs (receptor tyrosine kinases), which is expressed in macrophages, alleviates inflammatory responses through a negative feedback loop. However, the functional contribution of each TAM family member to the progression of hepatic inflammation remains elusive. In this study, we explore the role of individual TAM family proteins during autophagy induction and evaluate their contribution to hepatic inflammation. Among the TAM family of RTKs, AXL (AXL receptor tyrosine kinase) only induces autophagy in macrophages after interaction with its ligand, GAS6 (growth arrest specific 6). Based on our results, autophosphorylation of 2 tyrosine residues (Tyr815 and Tyr860) in the cytoplasmic domain of AXL in mice is required for autophagy induction and AXL-mediated autophagy induction is dependent on MAPK (mitogen-activated protein kinase)14 activity. Furthermore, induction of AXL-mediated autophagy prevents CASP1 (caspase 1)-dependent IL1B (interleukin 1, β) and IL18 (interleukin 18) maturation by inhibiting NLRP3 (NLR family, pyrin domain containing 3) inflammasome activation. In agreement with these observations, axl?/? mice show more severe symptoms than do wild-type (Axl+/+) mice following acute hepatic injury induced by administration of lipopolysaccharide (LPS) or carbon tetrachloride (CCl4). Hence, GAS6-AXL signaling-mediated autophagy induction in murine macrophages ameliorates hepatic inflammatory responses by inhibiting NLRP3 inflammasome activation. 相似文献
127.
DNA data and morphology reveal the existence of Kentrochrysalis streckeri Staudinger, 1880 (Lepidoptera: Sphingidae) instead of K. consimilis in South Korea 下载免费PDF全文
Min Jee Kim Sung‐Soo Kim Sei‐Woong Choi Youngho Cho Iksoo Kim 《Entomological Research》2016,46(3):210-219
In the present study, we determined that specimens of Kentrochrysalis consimilis collected from South Korea were K. streckeri, rather than K. consimilis, based on morphology, DNA barcodes and nuclear elongation factor 1 alpha (EF‐1α) sequences. The major morphological differences between K. streckeri and K. consimilis include the shape of forewing and hind‐wing pattern elements and male and female genitalia. The DNA barcode analysis of the South Korean specimens and the Russia‐originated K. streckeri showed a maximum sequence divergence of only 0.659% (4 bp), whereas that of the South Korean specimens and Japan‐originated K. consimilis showed a minimum sequence divergence of 2.965% (18 bp), indicating that the Korean specimens are, in fact, K. streckeri and not K. consimilis. Phylogenetic analyses both by Bayesian inference and maximum likelihood methods strongly clustered the South Korean specimens and Russian K. streckeri into one group, excluding K. consimilis. The EF‐1α‐based sequence and phylogenetic analyses of the two species also supported data from the DNA barcode, indicating the distribution of K. streckeri in South Korea, instead of K. consimilis. 相似文献
128.
Kyu-Tae Han Suk Yong Jang Sohee Park Kyung Hee Cho Ki-Bong Yoo Young Choi Eun-Cheol Park 《PloS one》2016,11(1)
Background
South Korea faces difficulties in the management of mental disorders, and those difficulties are expected to gradually worsen. Therefore, we analyzed the relationship between social welfare centers and hospital admission after outpatient treatment for mood disorders.Methods
We used data from the National Health Insurance Service National Sample Cohort 2002–2013, which included all medical claims filed for the 50,160 patients who were newly diagnosed with a mood disorder among the 1,025,340 individuals in a nationally representative sample. We performed a logistic regression analysis using generalized estimating equation (GEE) models to examine the relationship between social welfare centers and hospital admission after outpatient treatment for mood disorders (ICD-10: F3).Results
There was a 3.9% admission rate among a total of 99,533 person-years. Outpatients who lived in regions with more social welfare centers were less likely to be admitted to a hospital (per increase of five social welfare centers per 100,000 people; OR: 0.958; 95% CI: 0.919–0.999). Social welfare centers had an especially strong protective effect on patients with relatively mild mood disorders and those who were vulnerable to medical expenditures.Conclusions
Considering the protective role of social welfare centers in managing patients with mood disorders, health-policy makers need to consider strategies for activating mental healthcare. 相似文献129.
130.