• Korean Journal of Veterinary Research
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• v.37 no.4
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• pp.785-791
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• 1997

Theileria spp.의 생활환에 대해서는 여러종류의 책을 통해서 잘 소개되어 있다. 그중 Theileria spp.의 분열소체 즉, merozoite는 주로 숙주의 적혈구내에 존재하는데 진드기에 의해 흡혈되지 않으면 더이상 발육하지 못하고 생을 마감한다고 여겨 왔다. 그러나 적혈구내 merozoite가 임파구에 다시 들어가 schizont로 복귀하여 분열 증식된다는 가설은 아직까지 증명된 바 없다. 본 실험은 T sergenti merozoite의 schizont로의 복귀를 입증하고자 수행되었다. T sergenti에 감염되지 않은 3개월령의 송아지를 비장적출시킨 후 T sergenti merozoite에 감염된 순수적혈구를 인공감염시켰다. 인공감염후 경시적으로 혈액과 임파액을 채취하여 적혈구내 T sergenti 감염을 조사하고 백혈구 감별혈구를 계산하였으며 임파구내 schizont 출현을 관찰하여 다음과 같은 결과를 얻었다. 1. 혈구내원충 감염율(parasitemia : PE)은 인공감염후 28일째 최고치인 10.5%를 보였으며 그후 5%이내의 수준을 유지하다가 70일째 다시 8.5%의 상승점을 보였다. 2. 백혈구 감별혈구계산에서는 감염초기에는 호중구가 주종을 이루다가 감염후 19일을 기점으로 임파구(60~80%)가 급격히 증가하여 실험종료 때까지 유지되었다. 3. 인공감염후 19~23일, 59~63일 사이에 말초혈액내 임파구에서 분열 증식하고 있는 schizont를 관찰할 수 있었다. 4. 인공감염후 7일부터 림프액내 임파구의 크기가 커지면서 blast-formation이 진행되었으며 실험종료때까지 유지되었다. 이상의 결과로 보아 적혈구내 merozoite가 임파구에 다시 들어가 schizont로 복귀하여 분열 증식함을 입증하여 기존의 T sergenti 생활사는 수정되어야 된다고 사료된다.

• Korean Journal of Ecology and Environment
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• v.56 no.4
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• pp.406-413
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• 2023

Captive breeding and reintroduction are crucial strategies for conserving endangered species populations. However, fish raised in predator-free environments, show a lack of recognition of predationrelated stimuli such as chemical and visual signals. It is critical to recognize chemical signals from injured conspecifics, also known as alarm signals, and the order or shape of predators to indicate the spread of predation risk in the habitat. We conducted a laboratory experiment to determine and adjust the optimal exposure period to induce appropriate anti-predator behavior response to different types of stimuli (Chemical, Visual and Chemical+Visual) for the endangered species Microphysogobio rapidus. Our results demonstrate that predator avoidance behavior varies depending on the types of stimuli and the duration of predation risk exposure. First, the results showed captive-breed M. rapidus show lack of response against conspecific alarm signal (Chemical cue) before the predation risk exposure period and tend to increase response over predation risk exposure time. Second, response to predator (visual cue) tend to peak at 48 hours cumulative exposure, but show dramatic decrease after 72 hours cumulative exposure. Finally, response to the mixed cue (Chemical+visual) tend to peak prior to the predation risk exposure period and show reduced response during subsequent exposure periods. This experiment confirms the lack of responsiveness to conspecific alarm signals in captive-bred M. rapidus and the need for an optimal nature behavior enhancement program prior to release of endangered species. Furthermore, responsiveness to predator visual signal peak at 48 hours cumulative exposure, suggest an optimal predation risk exposure period of up to 48 hours.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.5
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• pp.435-444
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• 2023

Suitable environmental conditions in Saemangeum frequently favor phytoplankton growth. There have been occurrences of sudden phytoplankton blooms, surpassing the algae management standards. A model was designed to prevent such blooms using scientific predictive techniques to forecast and regulate the possibility of phytoplankton blooms. We propose effective and efficient algae control measures concerning every phytoplankton species optimized through the policy control of nutrients (DIN, PO4-P) from rivers and controlling lake salinity using gate operations. The probability of phytoplankton blooms was initially forecast using an artificial neural network algorithm based on observations. The model's Kappa number fluctuated from 0.7889 to 1.0000, indicating good to excellent predictive power. The Garson algorithm was then utilized to assess the significance of explanatory variables for every species. Meanwhile, the probability of phytoplankton blooms was anticipated depending on the DIN and salinity value changes. Therefore, the model predicted the precise DIN and salinity concentrations to inhibit phytoplankton blooms for each species. Hence, the green algae model can create effective proactive measures to avoid future phytoplankton blooms in enormous artificial lakes.

• 어항어장
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• s.38
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• pp.41-51
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• 1997

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.4
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• pp.561-567
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• 2002

Xylitol is a 5-carbons carbohydrate, which can be replaced with sucrose for preventing caries. The replication of Streptococcus mutans and its formation of artificial plaque were studied in the media containing xylitol. The combined effect of xylitol and other carbohydrates on Streptococcus mutans was also studied. The replication of Streptococcus mutans was inhibited according to the increased concentration of xylitol. Streptococcus mutans replicated at the initial stage of incubation in the media containing glucose, fructose or lactose, while replicating from the beginning of incubation in the media containing fructose as combining with xylitol. The formation of artificial plaque by Streptococcus mutans was significantly reduced in the media containing with xylitol and fructose. These results indicated that the replication of Streptococcus mutans was inhibited according to the increased concentration of xylitol, and the formation of artificial plaque by Streptococcus mutans was significantly inhibited in the media containing xylitol and fructose.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.28 no.1
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• pp.186-201
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• 2002

Fructan(Levan)은 식물체 및 미생물에서 발견되는 탄수화물로 이는 과당(fructose)이 $\beta$-2, 6 결합으로 연결되어 있는 polysaccaride 이다. 본 연구에서는 Fructan을 생성하는 미생물(Zymomonas mobilis)과 10% sucrose(기질), 1-2% 효모 추출물을 주성분으로 하는 배지를 사용하여 30-37$^{\circ}C$, pH 5.0-7.0에서 20-24시간 동안 배양한후 원심분리하여 균체를 제거하고 3배량의 알코올을 가하여 침전, 건조하여 얻은 Fructan의 화장품 원료로서의 가능성을 조사하였다. 보습효과에 있어서는 Hyaluronic acid와 유사하였으며, keratinocyte에 대한 세포증식 효과를 나타내었다. 또한 3-D culture에 의해 구축된 생인공 피부내에 0.05%의 sodium lauryl sulfate (SLS)를 사용하여 피부자극에 의한 초기 염증 반응을 유도한후 0.01mg/m1, 0.05mg/m1의 Fructan을 각각 처리하였을 때, SLS만을 처리한 생인공피부와 비교하여 세포증식효능을 보였고, SLS 자극물질로 유도된 전염증성 조절인자인 interleukin-l$\alpha$(IL-l$\alpha$)의 분비량을 조사 하였을때 0.01mg/ml, 0.05mg/ml의 Fructan을 처리한 생인공피부의 IL-l$\alpha$ 양이 Fructan을 처리하지 않은 것보다 상대적으로 감소하였다. 이러한 결과로 Fructan이 생인공 피부내 피부 세포의 증식효과를 나타낼 뿐만 아니라, 또한 피부자극물질에 의한 염증반응에 대해 자극완화효능이 있음을 알 수 있었다. 섬유아세포 및 동물을 이용한 안전성 시험에서도 독성이 없는 안전한 원료로 평가되었다.

• The Zoological Society Korea : Newsletter
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• v.12 no.2
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• pp.11-17
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• 1995

• Proceedings of the Korea Society of Poultry Science Conference
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• 2005.11a
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• pp.76-77
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• 2005

Effects of dietary killed salmonella and vancomycin on the performance and immune response was investigated in broiler chicks inoculated with Salmonella typhimurium. During 3 week(27 d) of age, experimental diet did not affect daily gain, feed intake and feed efficiency. Dietary killed salmonella and vancomycin decreased MnSOD activity. At 7day after Salmonella typhimurium inoculation, dietary killed salmonella and vancomycin increased, daily gain and feed efficiency of broiler chicks. At 7 and 15 day after salmonella inoculation, dietary killed salmonella and vancomycin decreased erythrocyte peroxidase activity, but elevated proliferation of PBMC stimulated with LPS and supernatant IL-1 level secreted by the PBMC. The results suggested that dietary killed salmonella and vancomycin improved the performance of broiler chicks due to modulate antioxidant system and innate immune response of broiler chicks innoculated with Salmonella typhimurium.

• Journal of Veterinary Clinics
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• v.17 no.1
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• pp.1-5
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• 2000

Microsporum gypseum을 인공감염시킨 기니픽에서 terbinafine의 치료효과 실험을 위한 전단계 실험으로서 인공감염시킨 기니픽에서 M. gyspeum의 생물학적 주기를 조사하였는데, 이것은 인공감염된 후 효과적인 치료와 평가의 시기를 결정하기 위해 필요하였다. M. gypseum으로 인공감염된 기니픽의 생물학적 주기는 급성기 이후에 자연치유되는 것이 특징이었다. 증식기는 감염 후 5일부터 11일까지 지속되었다. 따라서 다음 번의 치료효과 실험에서 인공감염 당일부터 9일간 계속 terbinafine을 경구투구하고, 마지막 투여 다음 날 진균학적 및 임상적 평가를 하기로 결정하였다.

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 1999.04a
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• pp.43-46
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• 1999