Population density of Culex tritaeniorhynchus was annually monitored to predict the possibility of a Japanese encephalitis (JE) outbreak at 10 collection sites throughout Republic of Korea (ROK) during mosquito season from 2011 to 2015. Prevalence of Cx. tritaeniorhynchus in ROK was spatially and timely very variable and was significantly highest at Busan city during August. Monthly average population density of Cx. tritaeniorhychus showed high correlation to the monthly average daily average temperature and monthly average precipitation. Two models for the estimation of occurrence of Cx. tritaeniorhynchus based on annual monthly daily average temperature and monthly precipitation are shown with linear regression equations of exp(0.413×temperature-0.949) and exp(0.01258×precipitation+3.777). JE vector surveillance and vector control is warranted as part of an effective JE management program at ROK.

Aster glehni Franchet et Schmidt is a compositae plant and has been known as a native specie in Ulleung Island, Korea. It is officially recognized as a regional specialty that grows only in this region. In 2014, brown and dark spots were observed on aster leaves in a forest research field, Jinju, Korea. A causal agent was isolated from the disease symptomatic leaves and identified as fungus Alternaria solani. Fungal morphological characteristics and molecular identification with internal transcribed spacer sequences were synchronized as A. solani. The isolated fungi reproduced the same disease symptoms when the fungus was artificially inoculated on healthy aster leaves. This is the first report that A. solani caused leaf blight disease in Aster glehni in Korea.

미꾸라지에서의 Nitrofuran계 대사물질인3-amino-2-oxazolidone (AOZ), 5-morpholinomethyl-3-amino-2-oxazolidinone (AMOZ), 1-ammino-hydantoin (AHD)와 semicarbazide (SEM)의 잔류량을 검사하기 위해HPLC-MS/MS를 이용한 신속한 정량법이 개발되었다. 2-nitrobenzaldehyde (2-NBA)를 이용해 50℃에서 1시간 동안 산 가수분해와 유도체화 과정을 거친 뒤에, 액-액 분배로 정제와 추출을 하였다. 회수율은 음성시료에 3가지 농도 0.5, 1.0, 2.0 μg/kg의 표준액을 첨가하여 평가하였고 평균 회수율은 75.1-108.1% 이었다. 정밀성(%RSD)은 일내 8.7% 이하, 일간 8.5% 이하였다. 직선성은 NBAOZ는 0.2-20 μg/Kg, NBAMOZ는 0.8-20 μg/Kg, NBAHD는 0.2-20 μg/Kg, NBSEM 는 0.1-20 μg/Kg 범위에서 모두 상관계수 0.99이상이었다. 검출한계(LOD)는 NBAOZ 0.06 μg/Kg, NBAMOZ 0.24 μg/Kg, NBAHD 0.06 μg/Kg, NBSEM 0.03 μg/Kg이었고, 정량한계(LOQ)는 NBAOZ 0.2 μg/Kg, NBAMOZ 0.8 μg/Kg, NBAHD 0.2 μg/Kg, NBSEM 0.1 μg/Kg 이었다. 가수분해 및 유도체화 소요시간을 1시간으로 줄여 만든 신속 간편한 이 시험법이미꾸라지 중 nitrofuran metabolites잔류량 분석에 적합함을 확인할 수 있었다.

선충절대기생세균(Pasteuria penetrans)이 감염되어 있는 온실토양을 이용하여 세균의 내생포자가 땅콩뿌리혹선충(Meloidogyne arenaria) 유충 표면에 부착하는데 대한 온도의 영향에 대해 시험하였다. 갓 부화된 뿌리혹선충 2령충(J2)을 페트리디쉬 내의 토양에 접종한 후 20℃, 25℃, 30℃, 35℃에서 7일간 처리하였다. 모든 온도에서 내생포자의 J2 부착률은 모두 100%로 나타났으나 J2당 내생포자 부착수는 25℃에서 28.3개로 가장 많았으며 30℃, 20℃ 및 35℃에서 각각 J2 당 20.2, 18.6 및 13.6개로 낮아졌다. J2를 접종하기 전에 세균이 있는 토양을 온도 별로 10일간 전처리하였을 때 내생포자 부착률은 실온에서의 60%에 비해 -30℃, 4℃, 40℃, 50℃ 및 100℃에서 각각 25.0, 31.7, 8.3, 5.0 및 0%로 현저하게 낮아졌다. J2 당 내생포자 부착수도 실온에서의 5.3개에 비해 -30℃, 4℃, 40℃, 50℃ 및 100℃에서 각각 3.5, 4.3, 1, 1, 0개로 적었다. P. penetrans 세균의 내생포자를 뿌리혹선충 종별로 J2에 부착 시험한 결과 땅콩뿌리혹선충에서는 100%였으나 당근뿌리혹선충(M. hapla)과 고구마뿌리혹선충(M. incognita)에서는 모두 0%로 본 균주는 뿌리혹선충 종에 대해 기주선호성을 가진 것으로 나타났다.

The coupling of autophagy and endoplasmic reticulum (ER) stress has been implicated in a variety of biological processes. However, little is known regarding the involvement of the autophagy/ER stress pathway in early embryogenesis or the underlying mechanism (s). Here, we showed that the developmental competence of in vitro-produced (IVP) bovine embryos was highly dependent on the autophagy/ER stress balance. Although relative abundances of autophagy-associated gene transcripts, including LC3, Atg5, and Atg7 transcripts, were high in oocytes and throughout the early stages of preattachment development, extensive autophagosome formation was only detected in fertilized embryos. Using inducer and inhibitor of autophagy, we showed that transient elevation of autophagic activity during early preattachment development greatly increased the blastocyst development rate, trophectoderm cell numbers, and blastomere survival; these same parameters were reduced by both inhibition and prolonged induction of autophagy. Interestingly, the induction of autophagy reduced ER stress and associated damage, while the developmental defects in autophagy-inhibited embryos were significantly alleviated by ER stress inhibitor treatment, indicating that autophagy is a negative regulator of ER stress inearly embryos. Collectively, these results suggest that early embryo genesis of IVP bovine embryos depends on an appropriate balance between autophagy and ER stress. These findings may increase our understanding of important early developmental events by providing compelling evidence concerning the tight association between autophagy and ER stress, and may contribute to the development of strategies for the production of IVP bovine blastocysts with high developmental competence.

Autophagy is known to be involved in a variety of biological processes. However, relatively a little is known regarding oocyte maturation and preimplantation development in mammals. Thus, the current study was conducted to investigate the role of autophagy in oocyte maturation and subsequent preimplantation development in pigs. Porcine oocytes were matured in the presence or absence of 1 μM rapamycin, an autophagy inducing agent, fertilized in vitro, and cultured to blastocyst stage. From Western blotting analysis, we found that active form LC3 was detected during in vitro maturation (IVM) period, suggesting the possible role of autophagy in oocyte maturation. Interestingly, treatment of rapamycin during IVM significantly increased nuclear maturation compared to control group. Importantly, rapamycin-assisted IVM greatly improved monospermic fertilization and blastocyst development rates compared to control embryos. In addition, we also found that cell number and blastomere survival in blastocysts were markedly increased in rapamycin treatment group, which was further evidenced by both elevation of anti-apoptotic transcript Bcl-XL and decrease of pro-apoptotic transcript Bax. Collectively, these results strongly suggest that induction of autophagy may contribute to the completion of nuclear and cytoplasmic maturation of porcine oocytes.

Despite of the presence of estradiol-17β (E2) in ovarian follicles, its role(s) in in vitro maturation (IVM) is still largely unknown, especially in pigs. Thus, the current study was conducted to investigate the effect of E2 on in vitro maturation (IVM) of porcine oocytes and subsequent preimplantation development using in vitro fertilization (IVF)- or somatic cell nuclear transfer (SCNT)-derived embryos. To define the effects of E2 on IVM and early embryogenesis, porcine oocytes were matured in the presence or absence of E2, fertilized in vitro and cultivated to blastocyst stage. Compared to control group, the production of MII oocytes was significantly increased by treatment with E2, accompanying with the increase in MPF content and ERK phosphorylation, and monospermic fertilization and blastocyst development rates were also greatly elevated in the E2-treated oocytes. In addition, the advantageous role of E2 was also found in blastomere survival, which was further evidenced by both elevation of anti-apoptotic transcript Bcl-XL and decrease of pro-apoptotic transcript Bax. Furthremore, these positive effects of E2 were highly reproducible in early development of SCNT embryos. Collectively, the current study strongly suggests that E2 can be used as a efficient IVM supplement leading to successful nuclear/cytoplasmic maturatioin in pigs.

Successful early embryogenesis of somatic cell nuclear transfer (SCNT) embryos is very important to produce cloned animals. However, poor preimplantation development of SCNT embryos has been a major obstacle to the generation of cloned animals due to a lack of understanding of developmental events and underlying mechanism(s). In the current study, we show that production of SCNT embryos with high developmental competence is dependent on the fusion method. Electrofusion causes spontaneous egg activation, accompanied by an increase in intracellular Ca2+ and improper nuclear remodeling, whereas Sendai virus (SV)-mediated fusion greatly reduces these events. In addition, SV-SCNT increased the blastocyst development rate and trophectoderm cell number compared to electrofusion-mediated SCNT (E-SCNT). In particular, expression of ER stress-associated genes and blastomere apoptosis were significantly increased in E-SCNT embryos, which could be alleviated by inhibition of ER stress or by using the SV-mediated fusion method. Taken together, these results strongly suggest that SV is a useful fusion material for improvement of preimplantation development of SCNT embryos through reduction of ER stress-associated apoptosis.

The epidemiology of reported food-borne disease (FBD) outbreaks from 2001 to 2008 in Korea and Japan were compared in this study. The outbreak rate of FBD in Japan was significantly higher although the average number of patient in each outbreak in Korea was much higher. In both countries, summer was the season when most FBD outbreaks occurred. The comparison study revealed that FBD outbreaks in spring were more frequent in Korea, and outbreaks in winter were more frequent in Japan. Almost half of FBD outbreaks were observed at restaurants in both countries while FBD outbreaks at schools and work-places in Korea were much higher than in Japan. The most frequent cause of bacterial FBDs in Korea was pathogenic Escherichia coli followed by Salmonella species. On the other hand, Campylobacter jejuni was the most frequent source of bacterial FBDs in Japan. Norovirus, which is related to uncontrolled hand hygiene and involvement of ill food workers, was the main cause of viral FBDs in both countries. In conclusion, there are common epidemiological characteristics as well as several differences in FBD outbreaks of Korea and Japan. These are suggested to be originated from the characteristic of climate, food sources, and life styles in two countries. Establishment of stricter control and surveillance system for FBD outbreaks are required for prevention and reduction of FBD outbreaks in both countries.

Our previous study demonstrated that Coprisin, a peptide from Copris tripartitus infected with bacterial pathogens, has an antibacterial activity. We assessed in this study whether Coprisin caused cellular toxicity in various mammalian cell lines. Coprisin selectively caused a marked drop of cell viability in Jurkat T cells, U937 cells and AML-2 cells belonging to the human leukemia cells but not in Caki cells and Hela cells. Fragmentation of DNA, a maker of apoptosis, was also confirmed in theleukemia cell lines but not in other cells. The Coprisin-induced apoptosis in leukemia cells was mediated by AIF (apoptosis inducing factor), a caspase -independent pathway.

Human mesenchymal stem cell (hMSCs) isolated from human adult bone marrow have self-renewal capacity and can differentiate into multiple cell types in vitro and in vivo. A number of studies have now demonstrated that MSCs can differentiate into various neuronal populations. Due to their autologous characteristics, replacement therapy using MSCs is considered to be safe and does not involve immunological complications. The basic helix-loop-helix (bHLH) transcription factor Olig2 is necessary for the specification of both oligodendrocytes and motor neurons during vertebrate embryogenesis. To develop an efficient method for inducing neuronal differentiation from MSCs, we attempted to optimize the culture conditions and combination with Olig2 gene overexpression. We observed neuron-like morphological changes in the hMSCs under these induction conditions and examined neuronal marker expression in these cells by RTPCR and immunocytochemistry. Our data demonstrate that the combination of Olig2 overexpression and neuron-specific conditioned medium facilitates the neuronal differentiation of hMSCs in vitro. These results will advance the development of an efficient stem cell-mediated cell therapy for human neurodegenerative diseases.

COPRISIN is an antibiotic substance extracted from Copris tripartitus. This study is intended to identify various cell biological stimuli that COPRISIN, widely known as an antibacterial substance, has on human cells and to identify its molecule mechanism. A variety of human cell lines were divided into epithelial cells including kidney cells or womb cells, and immunocyte including T cells or macrophages and, after their being cultivated and maintained, cell biological changes of the respective cells according to COPRISIN treatment were compared. As a result, it was confirmed that, different from other experiment cells, COPRISIN specifically caused cell kill in T cells and macrophages. That is, fragmentation of DNA, typical characteristics observed in the process of apoptosis, was confirmed in the nucleus of cells dying owing to COPRISIN treatment. An Apoptosis process is one dependent upon activity of caspase family protein, it was proved that COPRISIN medium cell kill process was one through a caspase-independent route such as AIF. Though it was found out that transcription of TNF-α and extracellular TNF-α secretion increased in blood cells stimulated by COPRISIN, it was also confirmed that TNF-α was a major medium factor in a COPRISIN induced cell kill process from the fact that a cell kill process by COPRISIN was not inhibited at all with TNF-α inhibiting antibody treatment. Above results revealed that COPRISIN, different from other tissue origin cells including kidney cells, can specifically induce apoptosis in immunocyte, which is caused by a caspase-independent cell signal transmission route.

Members of the Vps (Vacuolar protein sorting) protein family involved in the formation of the retromer complex have been discovered in a variety of species such as yeast, mouse, and human. A mammalian retromer complex is composed of Vps26, Vps29, and Vps35 proteins and plays and important role in cation-independent mannose-6-phosphate receptor retrieval from the endosome to the trans-Golgi network. In this study, we have identified the full-length sequences of the retromer components of Vps26, Vps29, and Vps35 in micro pigs. The cDNA sequences of these retromer components have been determined and the result showed there is 99% homology among the component counterparts from mouse, micro pigs, and humans. In addition, the retromer complexes formed with hetero-components were found in the brain of micro pigs. Based on above results, we suggest mammalian Vps components are well conserved in micro pigs.