• 수면정신생리
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• 제27권2호
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• pp.41-50
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• 2020

Napping is a natural and universal phenomenon. There are some differences depending on the age, but they are common throughout life. As research on naps in sleep medicine has recently increased, negative perceptions about naps are gradually decreasing with development of new and positive perspectives. First, naps relieve fatigue and sleepiness and increase arousal, improving cognitive abilities. Even in the process of memory consolidation, which allows retention of learned memory content, a period of short daytime sleep shows the same results as nocturnal sleep. In addition, evidence of the contribution of sleep to emotional regulation is increasing. The role of the nap has been extended recently to areas associated with immunity and pain. However, naps can disturb sleep at night. There are also concerns that habitual naps in old age are linked to cardiovascular risk and increased mortality. Various aspects and values of naps are being gradually unveiled. However, compared to that of night sleep, research on naps is insufficient, and more research on naps is required.

• Natural Product Sciences
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• 제28권3호
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• pp.93-104
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• 2022

Methicillin-resistant Staphylococcus aureus (MRSA) is a serious threat to the global healthcare system. Ineffective and resistance to antibiotic treatments have increased morbidity and mortality rates worldwide. New and effective antibiotics are needed to combat against bacterial resistance. Endophytic fungi are crucial reservoirs of novel bioactive metabolites. In particular, the secondary metabolites show promising therapeutic potential, notably, antibacterial. This review discussed the emerging potential of endophytic fungi as anti-MRSA agents. The ecological sources of endophytic fungi were discussed with the synthesis of bioactive metabolites. The mode of antibacterial actions was elucidated to give a better understanding of the mechanisms involved. This review may serve as an important reference for future discovery and developments of anti-MRSA agents from endophytic fungi.

• ALGAE
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• 제36권1호
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• pp.25-36
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• 2021

The mixotrophic dinoflagellate Tripos furca causes red tides in the waters of many countries. To understand its population dynamics, mortality due to predation as well as growth rate should be assessed. Prior to the present study, the heterotrophic dinoflagellates Noctiluca scintillans, Polykrikos kofoidii, Protoperidinium steinii, and mixotrophic dinoflagellate Fragilidium subglobosum were known to ingest T. furca. However, if other common heterotrophic protists are able to feed on T. furca has not been tested. We explored interactions between T. furca and nine heterotrophic dinoflagellates and one naked ciliate. Furthermore, we investigated the abundance of T. furca and common heterotrophic protists in coastal-offshore waters off Yeosu, southern Korea, on Jul 31, 2020, during its red tide. Among the tested heterotrophic protists, the heterotrophic dinoflagellates Aduncodinium glandula, Luciella masanensis, and Pfiesteria piscicida were able to feed on T. furca. However, the heterotrophic dinoflagellates Gyrodiniellum shiwhaense, Gyrodinium dominans, Gyrodinium jinhaense, Gyrodinium moestrupii, Oblea rotunda, Oxyrrhis marina, and the naked ciliate Rimostrombidium sp. were unable to feed on it. However, T. furca did not support the growth of A. glandula, L. masanensis, or P. piscicida. Red tides dominated by T. furca prevailed in the South Sea of Korea from Jun 30 to Sep 5, 2020. The maximum abundance of heterotrophic dinoflagellates in the waters off Yeosu on Jul 31, 2020, was as low as 5.0 cells mL-1, and A. glandula, L. masanensis, and P. piscicida were not detected. Furthermore, the abundances of the known predators F. subglobosum, N. scintillans, P. kofoidii, and Protoperidinium spp. were very low or negligible. Therefore, no or low abundance of effective predators might be partially responsible for the long duration of the T. furca red tides in the South Sea of Korea in 2020.

• Mycobiology
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• 제43권2호
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• pp.137-149
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• 2015

In the search for novel potent fungi-derived bioactive compounds for bioinsecticide applications, crude ethyl acetate culture filtrate extracts from 110 mangrove fungal endophytes were screened for their toxicity. Toxicity tests of all extracts against brine shrimp (Artemia salina) larvae were performed. The extracts with the highest toxicity were further examined for insecticidal activity against Spodoptera litura larvae and acetylcholinesterase (AChE) inhibition activity. The results showed that the extracts of five isolates exhibited the highest toxicity to brine shrimp at 50% lethal concentration ($LC_{50}$) values of 7.45 to 10.24 ppm. These five fungal isolates that obtained from Rhizophora mucronata were identified based on sequence data analysis of the internal transcribed spacer region of rDNA as Aspergillus oryzae (strain BPPTCC 6036), Emericella nidulans (strains BPPTCC 6035 and BPPTCC 6038), A. tamarii (strain BPPTCC 6037), and A. versicolor (strain BPPTCC 6039). The mean percentage of S. litura larval mortality following topical application of the five extracts ranged from 16.7% to 43.3%. In the AChE inhibition assay, the inhibition rates of the five extracts ranged from 40.7% to 48.9%, while eserine (positive control) had an inhibition rate of 96.8%, at a concentration of 100 ppm. The extracts used were crude extracts, so their potential as sources of AChE inhibition compounds makes them likely candidates as neurotoxins. The high-performance liquid chromatography profiles of the five extracts differed, indicating variations in their chemical constituents. This study highlights the potential of culture filtrate ethyl acetate extracts of mangrove fungal endophytes as a source of new potential bioactive compounds for bioinsecticide applications.

• 대한영양사협회학술지
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• 제25권2호
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• pp.83-104
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• 2019

Elevated high-sensitivity C reactive protein (hs-CRP) levels and metabolic syndrome are considered important predictors of cardiovascular mortality. This study examined the influence of the alcohol consumption level on the hs-CRP level and the prevalence of metabolic syndrome in South Koreans. The study subjects were 3,884 participants (${\geq}19$ years) from the KNHANES in 2015. The subjects were divided into four groups according to their alcohol consumption; None (none-alcohol consumption), Low (less than 15 g/day), Medium (15~29.9 g/day), and High (over than 30 g/day). The odds ratio for high-risk hs-CRP of men was significantly lower in the Low or Medium groups compared to the None group. In women, the odds ratio for high-risk hs-CRP was not decreased in the Low or Medium groups but was significantly higher in the High group than in the None group. Compared to nondrinkers, the prevalence of metabolic syndrome was lower in the Low group and Medium group in both men and women, whereas it was significantly higher in the High group in men only. In particular, the prevalence of low HDL-cholesterol was lower in all drinking groups. When the confounding factors were adjusted, the odds ratio for low HDL-cholesterol appeared to decline in the Low groups in both men and women. On the other hand, in the Medium group, women showed an elevated odds ratios of high blood pressure (HBP) and high fasting plasma glucose but men showed an elevated odds ratios of HBP and high triglyceride levels. The overall results suggest that low alcohol consumption is more appropriate than medium alcohol consumption. Nevertheless, more study will be needed to evaluate the appropriate alcohol consumption level.

• Toxicological Research
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• 제32권3호
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• pp.245-250
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• 2016

3-Methylpentane ($C_6H_{14}$, CAS No. 96-14-0), isomer of hexane, is a colorless liquid originating naturally from petroleum or natural gas liquids. 3-Methylpentane has been used as a solvent in organic synthesis, as a lubricant, and as a raw material for producing carbon black. There is limited information available on the inhalation toxicity of 3-methylpentane, and the aim of this study was to determine its subacute inhalation toxicity. According to OECD Test Guideline 412 (subacute inhalation toxicity: 28-day study), Sprague Dawley rats were exposed to 0, 284, 1,135, and 4,540 ppm of 3-methylpentane for 6 hr/day, 5 days/week for 4 weeks via whole-body inhalation. Mortality, clinical signs, body weights, food consumption, hematology, serum chemistry, organ weights, and gross and histopathological findings were compared between control and all exposure groups. No mortality or remarkable clinical signs were observed during the study. No gross or histopathological lesions, or adverse effects on body weight, food consumption, hematology, serum chemistry, and organ weights were observed in any male or female rats in all exposure groups, although some statistically significant changes were observed in food consumption, serum chemistry, and organ weights. In conclusion, the results of this study indicate that no observable adverse effect level (NOAEL) for 3-methylpentane above 4,540 ppm/6 hr/day, 5 days/week for rats.

• 대한한방내과학회지
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• 제39권4호
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• pp.676-685
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• 2018

Objectives: The aim of this study was to estimate the single oral toxicity of Peucedani Radix (PR) ethanol extracts. PR is one of the important herbs for removal of phlegm, the viscous turbid pathological product that can accumulate in the body and cause a variety of diseases. However, research on the pharmacologic toxicity of PR is lacking. Methods: In this study, PR was orally administered to 5-week-old male ICR mice at an oral dose of 2,000, 3,000, or 5,000 mg/kg. After a single-dose administration, the mortality and behavioral changes were observed daily and body weights were measured every two days. After 14 days, the organ weight, organ index, macroscopy, hematological analysis, and serum biochemistry analysis were determined. Results: No mortality, body weight changes, abnormal behavioral changes, or anatomical signs of toxicity were found. The organ weight, organ index, hematological analysis, and serum biochemistry analysis were also within the normal ranges. Conclusions: These results suggest that the 50% lethal dose of PR is more than 5,000 mg/kg. This could indicate that PR is a safe drug without acute toxicity and side effects.

• International Journal of Industrial Entomology and Biomaterials
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• 제16권2호
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• pp.93-99
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• 2008

The turnip aphid is a worldwide pest, damaging mainly to crucifers. In order to understand the life parameters of Lipaphis erysimi for the eventual goal of control, the developmental periods, survival rates, lifespan, and fecundity of the species were investigated under five temperature regimes ($15^{\circ}C-35^{\circ}C$). Furthermore, the efficacy of several environment-friendly agricultural materials (EFAMs) that are on the market was subjected to test in order to obtain further accurate information. The developmental period of the turnip aphid nymph was longest at $15^{\circ}C$ as 16.9 days, shortened as temperature goes up to $25^{\circ}C$ (5.4 days), and then somewhat increased at $30^{\circ}C$ (5.9 days), suggesting that the most efficient temperature for nymphal development could be around $25^{\circ}C$. Mortality of the nymphal turnip aphid was obvious at $35^{\circ}C$, whereas it was minimal at other temperature schemes. The longevity of adults shortened as temperature goes up to $30^{\circ}C$. In particular, the maximum lifespan for adults continued for 55 days at $15^{\circ}C$, but shortened to 21 days at $30^{\circ}C$. The total fecundity was 35.7 at $15^{\circ}C$, 81 at $20^{\circ}C$, 64.2 at $25^{\circ}C$, and 6.6 individuals at $30^{\circ}C$, showing the highest fecundity at $20^{\circ}C$. After the turnip aphids were successfully stabilized in indoor environment the insecticidal activity was tested and mortality was determined 12, 24, 36, and 48 hrs after EFAMs are treated. Several on-the-market EFAMs showed more than 90% of insecticidal activity within 24 hrs or 48 hrs, but a few showed less than 90% activity, signifying importance of selection of proper EFAMs.

• 한국가축번식학회지
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• 제27권4호
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• pp.287-297
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• 2003

The aim of this review is to give insight into the reproduction potential of the Korean native goat(KNG) doe. The mean age of the first estrus in the KNG doe is 141.24$\pm$18.l7 days. The length of the estrous cycle was recorded as being 20.58$\pm$2.63 days, with the mean duration of estrous period being 17.8$\pm$7.3 to 32.9$\pm$1.2 h, and the duration of the post-partum anestrous period being 13.4(9 to 18) to 30.1$\pm$3.8 days in the KNG doe. The ages at first delivery are 10 to 12 months(56.3％) in the KNG doe. The KNG does are no restricted breeding season, because estrus and kiddings are observed throughout the year. The mean gestation period of the KNG doe is recorded as being 150.69$\pm$6.14 days with parities having no significant effect on gestation length. The mean interval between parturitions in the KNG doe is 207.78$\pm$1.72 days with parities and birth type having no significant effect on kidding intervals. The mean litter sizes at birth in the KNG doe are 1.69$\pm$0.03 heads, and litter size at birth was affected (P<0.05) by parity. The mean birth weight of kid in the KNG is 2.04$\pm$0.30 kg with a variety as being 2.28$\pm$0.26, 2.11$\pm$ 0.30 and 1.64$\pm$0.19 kg for singles, twins and triplets over of birth type, respectively. The mean mortality of 635 kids in the KNG is 23$\pm$1 ％ with a variety as being 28$\pm$3, 21$\pm$2, 16$\pm$3 and 46$\pm$15 ％ for singles, twins, triplets and quadruplets of birth type, respectively.

• 농약과학회지
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• 제19권4호
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• pp.418-423
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• 2015

포식성 천적 사막이리응애에 대하여 9종 살응애제의 영향을 평가하였다. 실험 살응애제 중 cyenopyrafen. spirodiclofen, spiromesifen, acequinocyl, bifenazate, flufenoxuron과 cyflumetofen 등은 사막이리응애의 암컷성충에 저독성을 나타내었으며, 암컷성충의 산란수와 산란된 난의 부화에 큰 영향이 없었다. 또한 이들 살응애제의 난에 대한 처리에서도 부화율에 영향이 없었다. Etoxazole은 암컷성충의 생존율에는 큰 영향이 없었으나 이들이 산란한 난의 부화율이 매우 낮았으며, 난에 대한 처리에서 높은 치사율을 나타내었다. Pyraclofos는 암컷성충에 대해 고독성으로 100%의 치사율을 나타내었다. Cyenopyrafen. spirodiclofen, spiromesifen, acequinocyl, bifenazate, flufenoxuron과 cyflumetofen 등을 처리한 먹이를 섭식한 암컷성충은 생존율과 산란수에 실질적인 영향을 받지 않았다. 이상의 결과로 보아 cyenopyrafen. spirodiclofen, spiromesifen, acequinocyl, bifenazate, flufenoxuron과 cyflumetofen 등은 식식성응애류의 종합관리체계에서 사막이리응애와 함께 이용될 수 있을 것으로 생각된다.