기후변화가 국내 주요 외래 산림해충 발생에 미치는 영향을 리뷰하였다. 국내 주요 외래 산림해충으로 소나무 재선충병, 주홍날개꽃매미, 미국선녀벌레, 갈색날개매미충, 소나무허리노린재 등이 보고되어 있다. 외래 산림 해충에 대한 기후변화 영향 평가는 종 분포 모델에 기반을 둔 발생위험도 평가를 통해 분석되고 있었다. 여러 국내 연구 사례들은 기후변화가 진행됨에 따라 소나무재선충병의 발생위험도가 증가함을 보여주었다. 일본 등 국외 연구 사례에서도 기후변화에 의해 온대지역 소나무림의 소나무재선충병 발생위험이 증가할 것으로 예측되었다. 주홍날개꽃매미도 기후변화가 진행함에 따라 발생위험도가 증가하였다. 그러나 벼룩좀벌류 등의 천적이 주홍날개꽃매미 밀도를 감소시키므로 현실적인 기후변화 영향평가를 위해서는 천적류에 대한 기후변 화 영향 평가가 필요할 것으로 판단되었다. 산림 분야 기후변화 대응을 위해서는 산림해충 및 천적류에 기후변화 영향평가를 기반으로 한 적응 대책의 필요성이 확인되었다.

The genus Chroomonas is a group of blue-green colored cryptomonads. This study describes two freshwater Chroomonas species for the first time in South Korea: Chroomonas nordstedtii Hansgirg and Chroomonas coerulea (Geitler) Skuja. We examined the morphology and ultrastructure of these species by light microscopy, scanning electron microscopy, and transmission electron microscopy. These two Chroomonas species were blue-green colored and ovate to oval-shaped. Chroomonas nordstedtii was characterized by two Maupas ovals with hexagonal periplast plates, whereas C. coerulea was characterized by one eyespot with rectangular periplast plates. A molecular phylogeny with data from nuclear SSU rRNA and chloroplast rbcL genes revealed that Korean C. nordstedtii formed a distinct clade with NIES-708, NIES-1004 from Japan, and UTEX 2779 from Colorado, USA, while C. coerulea formed a clade with ACOI 1366 from Portugal.

Chlorella gloriosa (Chlorellaceae, Trebouxiophyceae) was isolated from seawater off the coast of the Dokdo Islands in Korea. An axenic culture was established using the streak-plate method on f/2 agar media supplemented with antibiotics, allowing identification of the isolate by morphological, molecular, and physiological analyses. The morphological characteristics observed by light and electron microscopy revealed typical morphologies of C. gloriosa species. The molecular phylogenetic inference drawn from the small-subunit 18S rRNA sequence verified that the microalgal strain belongs to C. gloriosa. Additionally, gas chromatography-mass spectrometry analysis showed that the isolate was rich in nutritionally important omega-3 and -6 polyunsaturated fatty acids and high-performance liquid chromatography analysis revealed that the high-value antioxidants lutein and violaxanthin were biosynthesized as accessory pigments by this microalga, with arabinose, galactose, and glucose as the major monosaccharides. Therefore, in this study, a Korean marine C. gloriosa species was discovered, characterized, and described, and subsequently added to the national culture collection.

2017년 국내 육성 사과 ‘아리수’ 품종에서 노린재류에 의한 피해와 유사한 반점 증상이 확인되었다. 사과 과실 전면에 발생하는 이 반점 증상은 크기가 2∼4 mm이며 진한 갈색, 짙은 고동색으로 반점 중심부가 약간 함몰되는 형태를 가진다. 이 연구는 이러한 반점증상의 원인이 노린재에 의한 피해인지 여부를 알기 위해 수행하였다. 노린재류는 접종 전 채집하였고, 6월 초순부터 ‘아리수’ 사과에 약 15일 간격으로 썩덩나무노린재와 갈색날개노린재를 각각 접종하였다. ‘아리수’ 사과의 수확기인 9월 초순까지 총 5회(6월 상순, 7월 상순, 7월 중순, 8월 상순, 8월 중순) 접종하였으며, 접종후 접종시기별로 피해 양상을 확인하였다. 6월 상순에 노린재에 의해 가해 받은 과실은 비대하지 못하거나 낙과하였다. 다른 시기에 노린재에 의해 가해 받은 접종 1~2일후 흡즙구멍을 확인할 수 있었고, 5일 후부터는 가해 받은 부위 주변이 붉게 착색되는 halo 증상이 나타났다. 노린재류에 의한 ‘아리수’ 사과의 피해양상은, 기 보고된 ‘후지’ 품종에서의 피해양상과 거의 유사하였다. 실험결과 2017년 ‘아리수’ 사과에 발생한 반점증상은 노린재에 의한 것이 아님을 확인할 수 있었다.

Recently, food delivery apps are seeing rapid growth into a market worth 1 trillion won under a simple but unique business model of connecting nearby restaurants with consumers via smartphone. Though basic similarities with social commerce exists in aspects such as mail-order sales intermediaries, startups, types of services and market competition structure, food delivery apps resemble social commerce in many ways in that they use excessive marketing to secure market dominance, causing a spike in consumer complaints. If the excessive marketing and increase in customer complaints are not rectified, the food delivery app could also see rapid decline as it gradually grows distant from consumers, just like social commerce. Accordingly, this study will identify the factors consumers recognize as important for continuous use vis-a-vis social commerce and food delivery apps to perform an empirical analysis on what areas need improvement. After deriving the four upper factors of product, information system and service along with eight sub-factors by referring to existing literature, the areas with opportunity for improvement were derived through satisfaction level and relative importance evaluation. The results of this study present a strategic direction for maintaining customers of social commerce and food delivery apps.

Plasma glutathione peroxidase (pGPx) is an extracellular antioxidative selenoenzyme which has been detected in various adult tissues, but little is known about the expression and distribution of pGPx during embryogenesis. To investigate the expression patterns of pGPx during embryogenesis, we performed quantitative real-time PCR, in situ hybridization, Western blot, and immunohistochemistry analyses in whole embryos or each developing organ of mice on embryonic days (E)7.5–18.5. In whole embryos of E7.5–8.5, pGPx mRNA was more typically expressed in extra-embryonic tissues including ectoplacental cone, trophectoderm, and decidual cells than in embryos. However, after E9.5, pGPx mRNA and protein levels were increased in the embryos with differentiation and growth, but trended to gradually decrease in the extra-embryonic tissues until E18.5. In sectioned embryonic tissues on E13.5–18.5, pGPx mRNA and protein were mainly expressed in the developing nervous tissues, the sensory organs, and the epithelia of lung, skin, and intestine, the heart and artery, and the kidney. In particular, pGPx immunoreactivity was very strong in the developing liver. These results indicate that pGPx is spatio-temporally expressed in various embryonic organs as well as extra-embryonic tissues, suggesting that pGPx may function to protect the embryos against endogenous and exogenous reactive oxygen species during organogenesis.

Nicotine, a major teratogen of cigarettes smoke induces embryonic abnormalities during the early stages of organogenesis. In this study, the protective effect of β-carotene against nicotine–induced embryos was evaluated by morphologic scoring, nile blue staining, lipid peroxidation, SOD activity assay and real-time PCR. The embryos exposed to nicotine (1 μM) revealed remarkable morphological anomalies compared to normal control group (p<0.05), but when β-carotene (1×10‒4 μM or 5×10‒4 μM) was added concurrently to the embryos exposed to nicotine, morphological parameters were significantly improved (p<0.05). Nicotine induced oxidative stress by increased lipid peroxidation, expression of proinflammatory cytokines (TNF-α and IL-1β), caspases-3 and decreased SOD activity. However, administration of β-carotene (1×10‒4 μM or 5×10‒4 μM) restored the SOD level and decreased oxidative damage in the embryos. These results indicate that β-carotene effectively counteracts the deleterious effects of nicotine on embryos and attenuates oxidative damage possibly through its antioxidant effects.

Nicotine, a major toxic component in tobacco smoke, leads to severe embryonic damages on organogenesis. We investigated if resveratrol can inhibit the nicotine–induced teratogenesis in the cultured mouse embryos (embryonic day 8.5) for 48 hours using a whole embryo culture system. The embryos exposed to nicotine (1 μM) revealed severe morphological anomalies, the increased levels of caspase-3 mRNA and lipid peroxidation, and further the lowered levels of mitochondrial manganese superoxide dismutase (SOD), cytosolic glutathione peroxidase (GPx), phospholipid hydroperoxide GPx, hypoxia-inducible factor 1α, and sirtuin mRNAs and SOD activity significantly compared to normal control group (p<0.05). However, whenre sveratrol(1×10‒5 μMor1 ×10‒4 μM) was added concurrently to the embryos exposed to nicotine, these all parameters were significantly improved (p<0.05).These findings indicate that resveratrol has a protective effect against nicotine-induced teratogenesis in mouse embryos throughout antioxidative and anti-apoptotic activities.

To investigate the effect of carnosine on exhaustive exercise, swimming tests were conducted weekly with loads corresponding to 5% of body weight attached to the tails of mice, and the swimming time to exhaustion was measured. Eighty male ICR mice were divided into four groups, to which carnosine was administered at doses of 0 (control), 10, 50, and 250 mg/kg/day, respectively, for a period of four weeks. At the end of swimming exercise challenges, serum biochemistry, oxidative stress enzyme activity, and antioxidant enzyme activity in tissues were determined. Treatment with 250 mg/kg carnosine resulted in a significant increase in swimming times to exhaustion, compared to the control group in the first (P<0.01) and third week (P<0.05). Significantly lower serum lactate levels were observed after the swimming exercise in the carnosine-treated groups (10 and 250 mg/kg), compared with the control (P<0.01). Malondialdehyde levels in the liver (10 and 50 mg/kg carnosine treated groups) and skeletal muscle (250 mg/kg carnosine treated group) were significantly lower, compared with the control (P<0.05). Significantly lower protein carbonyl levels in skeletal muscle were observed in the 50 and 250 mg/kg carnosine treated groups, compared with the control (P<0.01). Superoxide dismutase and glutathione peroxidase activities in skeletal muscle did not differ significantly among the groups. These results indicate that carnosine may improve swimming exercise capacity by attenuating production of lactate and reducing oxidative stress in mice.

This study is intended to examine the motor skill learning and treadmill exercise on motor performance and synaptic plasticity in the cerebellar injured rats by harmaline. Experiment groups were divided into four groups and assigned 15 rats to each group. GroupⅠ was a normal control group(induced by saline); GroupⅡ was a experimental control group(cerebellar injured by harmaline); GroupⅢ was a group of motor skill learning after cerebellar injured by harmaline; GroupⅣ was a group of treadmill exercise after cerebellar injured by harmaline. In motor performance test, the outcome of groupⅡ was significantly lower than the groupⅢ, Ⅳ(especially groupⅢ)(p<.001). In histological finding, the experimental groups were destroy of dendrities and nucleus of cerebellar neurons. GroupⅢ, Ⅳ were decreased in degeneration of cerebellar neurons(especially groupⅢ). In immunohistochemistric response of synaptophysin in cerebellar cortex, experimental groups were decreased than groupⅠ. GroupⅢ's expression of synaptophysin was more increased than groupⅡ, Ⅳ. In electron microscopy finding, the experimental groups were degenerated of Purkinje cell. These result suggest that improved motor performance by motor skill learning after harmaline induced is associated with dynamically altered expression of synaptophysin in cerebellar cortex and that is related with synaptic plasticity.

Maternal hypoxia induced by a variety of exogenous oxidative stresses such as ethanol intake, diabetes, and cigarette during pregnancy provokes the impaired embryonic gene expression and developmental malformations. We investigated the gene expression patterns of the representative selenium containing antioxidant enzymes (selenoproteins) such as cytosolic GPx (cGPx), gestrointestinal GPx (GI-GPx), plasma GPx (pGPx), phospholipid hydroperoxide GPx (PHGPx), and selenoprotein P (SePP) in the cultured mouse embryos under normal or hypoxic (low oxygen state, 5% O₂) condition at embryonic day 8.5 for 2 days using real-time PCR analysis. cGPx, pGPx, and SePP mRNAs were significantly decreased, but GI-GPx and PHGPx mRNAs were remarkably increased in the hypoxic state compared to normal gassing state (p<0.05). These findings indicate that hypoxic condition leads to the unusual expressions of selenoproteins during mouse organogenesis.