• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
• /
• 제10권S_4호
• /
• pp.197-206
• /
• 2001

The long-range transport mechanisms of Asian dust were analyzed based on the synoptic weather system and numerical simulation by using NCEP/NCAR reanalysis and TOMS data during the periods of 1996-2001. We classified the whole weather types of eastern Asia during spring and created the representative weather types during the yellow sand events using cluster analysis and weather charts for the last 6 years(1996~2001). These long-range transport mechanisms were related to various pressure patterns including high and low, trough and ridge, and upper-level fronts. Case studies of the yellow sand events have performed by the simulation of MM5 with meteorological elements such as the horizontal wind of u and v component, potential temperature, potential vorticity, and vertical circulation during the episodic days(2~8 March 2001). In addition, the origin of the long-range transport was examined with the estimation of backward trajectory using HYSPLIT4 Model. In this paper, we concluded that three weather types at 1000 hPa, 850 hPa, 500 hPa, and 300 hPa levels were classified respectively. The dominant features were the extending continental outflow from China to Korea at 1000 hPa and 850 hPa levels, the deep trough passage and cold advection at 500 hPa and 300 hPa levels during the yellow sand events. And also, we confirmed the existence of pola $r_tropical jets in the upper-level, the behavior of potential vorticity over Korea, the estimation of potential vorticity through vertical cross section, and the transport of yellow sand through backward trajectories.es.

• Asian Pacific Journal of Cancer Prevention
• /
• 제15권14호
• /
• pp.5659-5665
• /
• 2014

Background: To investigate the antioxidant value and anticancer functions of mitragynine (MTG) and its silane-reduced analogues (SRM) in vitro. Materials and Methods: MTG and SRM was analyzed for their reducing power ability, ABTS radical inhibition and 1,1-diphenyl-2-picryl hydrazylfree radicals scavenging activities. Furthermore, the antiproliferation efficacy was evaluated using MTT assay on K 562 and HCT116 cancer cell lines versus NIH/3T3 and CCD18-Co normal cell lines respectively. Results: SRM and MTG demonstrate moderate antioxidant value with ABTS assay (Trolox equivalent antioxidant capacity (TEAC): $2.25{\pm}0.02$ mmol trolox / mmol and $1.96{\pm}0.04$ mmol trolox / mmol respectively) and DPPH ($IC_{50}=3.75{\pm}0.04mg/mL$ and $IC_{50}=2.28{\pm}0.02mg/mL$ respectively). Both MTG and SRM demonstrate equal potency ($IC_{50}=25.20{\pm}1.53$ and $IC_{50}=22.19{\pm}1.06$ respectively) towards K 562 cell lines, comparable to control, betulinic acid (BA) ($IC_{50}24.40{\pm}1.26$). Both compounds showed concentration-dependent cytototoxicity effects and exert profound antiproliferative efficacy at concentration > $100{\mu}M$ towards HCT 116 and K 562 cancer cell lines, comparable to those of BA and 5-FU (5-Fluorouracil). Furthermore, both MTG and SRM exhibit high selectivity towards HCT 116 cell lines with selective indexes of 3.14 and 2.93 respectively compared to 5-FU (SI=0.60). Conclusions: These findings revealed that the medicinal and nutitional values of mitragynine obtained from ketum leaves that growth in tropical forest of Southeast Asia and its analogues does not limited to analgesic properties but could be promising antioxidant and anticancer or chemopreventive compounds.

• Parasites, Hosts and Diseases
• /
• 제30권1호
• /
• pp.15-20
• /
• 1992

충북 청주시 소재 도축장에서 6개월령 균격돈 (Yorkshlre, Landrace, Duroc 및 Hampshire의 교잡종)을 조사하여 Asian Taenin saginata 예미충의 간장내 감염률을 조사하였다. 낭미충은 1.01% (256/25,358 마리)의 돼지에서 발견되었으며 낭미충의 상태는 살아있었거나 (0.01%, 3/25,358), 죽은 후 변성되어 있었거나 (0.12%, 30/25,358), 석회화된 (0.88%, 223/25,358) 상태로 검출되었다. 감염된 제지간 중 석회화된 낭미충만 발견되는 경우가 87.1%(223/256)로 대부분이었다. 간장내에서는 우측엽(14.7%), 우중엽(29.9%), 좌중엽(28.2%), 좌측엽 (27.l%)에 고르게 분포하였고, 표면과 실질에도 각각 45.8% 및 54.2%로서 고르게 분포하였다. 남미충의 크기는 생존상태에서 2.07~2.14$\times$1.98~2.01 mm이었고, 불규칙소구(rudimetary hooklets)는 17.0% (8/47)의 낭미충에서 발견되었다. 이상의 결과는 돼지에 자연 감염된 Asian Taenia sagippata 낭미충이 이제까지 무구조충(Taenia saginata)으 로 오인되었던 Asian Taenia saginata의 인체 감염원이 되었을 것으로 생각되었다.

• Parasites, Hosts and Diseases
• /
• 제30권1호
• /
• pp.59-62
• /
• 1992

동남아시아를 여행하고 귀국한 후부터 시작된 약 1개월 동안의 복통, 설사 및 체중 감소를 주소로 내원한 서울이 거주지인 32세의 남자 환자가 구충증으로 진단되었다. 혈액 검사상 백혈구 수(16,750개111) 및 호산구의 백분율(33.7%)이 모두 상승되어 있었으나 빈혈 소견은 없었다. 대변 검사상 전형적인 구충의 충란이 대량 발견되었으며, S상결장경검사시 직장에서 적출된 충체 3마리를 관찰한 결과, 기생 부위가 전형적이지는 않았으나, 구강 및 생식기 등의 형태학적인 특징을 고려하여 듀비니구충(Ancylestoma duodenale)의 성충(♂: 1, ♀: 2마리)으로 동정 할 수 있었다. 구충제 (aetendazole)를 투여한 후 상기한 모든 증상이 급속히 호전되었다. 해외 여행시 감염되어 국내에 수입된 기생충 감염의 한 중례로 생각되며, 인체의 대장에 이소기생 (이소기생)한 구충 감염을 직접 확인한 드문 경우로 생각된다.

• Parasites, Hosts and Diseases
• /
• 제37권4호
• /
• pp.265-270
• /
• 1999

The gene encoding Plasmodium vivax circumsporozoite protein (PvCSP) exhibits polymorphism in many geographical isolates. The present study was designed to investigate polymorphism in PvCSP gene of P. vivax isolates in Korea. Thirty isolates, obtained from indigenous cases in Yonchon-gun, Kyonggi-do in 1997, were subjected for sequencing and RFLP analysis of the repeat and post-repeat regions of PvCSP gene and two genotypes (SK-A and SK-B) were identified. The genotype of 19 isolates was SK-A and that of 11 isolates was SK-B. Although the number of 12-base repeats present in SK-A was three while two were found in a Chinese strain CH-5, the repeat sequence of SK-A was identical to that of CH-5 except for one base substitution. Compared with known data there was no identical isolates with SK-B, but the sequence of SK-B was similar to that of a North Korean (NK) isolate. These results indicate that two genotypes of PvCSP coexist in the present epidemic area of Korea and the present parasite may originate from East Asia. RFLP would be useful to classify genotypes of P. vivax population instead of gene sequencing.

• Parasites, Hosts and Diseases
• /
• 제53권3호
• /
• pp.315-320
• /
• 2015

Acarapis mites, including Acarapis woodi, Acarapis externus, and Acarapis dorsalis, are parasites of bees which can cause severe damage to the bee industry by destroying colonies and decreasing honey production. All 3 species are prevalent throughout many countries including UK, USA, Iran, Turkey, China, and Japan. Based on previous reports of Acarapis mites occurring in northeast Asia, including China and Japan, we investigated a survey of Acarapis mite infestations in honey bees in Korean apiaries. A total of 99 colonies of Apis mellifera were sampled from 5 provinces. The head and thorax of 20 bees from each colony were removed for DNA extraction. PCR assays were performed with 3 primer sets, including T, A, and K primers. Results indicated that 42.4% (42/99) of samples were Acarapis-positive by PCR assay which were sequenced to identify species. Each sequence showed 92.6-99.3% homology with reference sequences. Based on the homology, the number of colonies infected with A. dorsalis was 32 which showed the highest infection rate among the 3 species, while the number of colonies infected with A. externus and A. woodi was 9 and 1, respectively. However, none of the Acarapis mites were morphologically detected. This result could be explained that all apiaries in the survey used acaricides against bee mites such as Varroa destructor and Tropilaelaps clareae which also affect against Acarapis mites. Based on this study, it is highly probable that Acarapis mites as well as Varroa and Tropilaelaps could be prevalent in Korean apiaries.

• Parasites, Hosts and Diseases
• /
• 제52권4호
• /
• pp.413-418
• /
• 2014

Hydatid cyst caused by Echinococcus granulosus is one of the most important parasitic diseases around the world and many countries in Asia, including Iran, are involved with this infection. This disease can cause high mortality in humans as well as economic losses in livestock. To date, several molecular methods have been used to determine the genetic diversity of E. granulosus. So far, identification of E. granulosus using real-time PCR fluorescence-based quantitative assays has not been studied worldwide, also in Iran. Therefore, the aim of this study was to investigate the genetic diversity of E. granulosus from center of Iran using real-time PCR method. A total of 71 hydatid cysts were collected from infected sheep, goat, and cattle slaughtered in Isfahan, Iran during 2013. DNA was extracted from protoscolices and/or germinal layers from each individual cyst and used as template to amplify the mitochondrial cytochrome c oxidase subunit 1 gene (cox1) (420 bp). Five cattle isolates out of 71 isolates were sterile and excluded from further investigation. Overall, of 66 isolates, partial sequences of the cox1 gene of E. granulosus indicated the presence of genotypes G1 in 49 isolates (74.2%), G3 in 15 isolates (22.7%), and G6 in 2 isolates (3.0%) in infected intermediate hosts. Sixteen sequences of G1 genotype had microgenetic variants, and they were compared to the original sequence of cox1. However, isolates identified as G3 and G6 genotypes were completely consistent with original sequences. G1 genotype in livestock was the dominant genotype in Isfahan region, Iran.

• 한국농림기상학회지
• /
• 제5권2호
• /
• pp.116-127
• /
• 2003

태국 북서부의 Tak 지방에 KoFlux(Korean Flux Network) 연구의 일환으로서 플럭스 관측소(Tak flux measurement, TFM site)가 설립되었다. 이곳에서 이산화탄소와 물, 그리고 에너지 플럭스를 관측하기 위해 와 공분산시스템(eddy covariance system)을 적용하였으며 관측된 자료는 실시간 자료 감시 및 모사 시스템(Real time monitoring and simulation system, RTMASS)을 이용하여 처리되어 전송된다. RTMASS는 KoFlux-DIS(Data information system)의 핵심 구조이고 원격지 시스템과 중앙 시스템으로 나누어지며 자료의 수집 및 전송. 자료의 저장 및 처리가 본 시스템의 주된 기능이다. 난류특성과 미기상학적인 분석 자료에 따르면, TM 관측소는 열대 낙엽수림에 대한 다양한 플럭스 및 에너지 수지를 관측하고 분석하는데 적합하다고 할 수 있다.

• Parasites, Hosts and Diseases
• /
• 제58권1호
• /
• pp.61-65
• /
• 2020

Majority of the imported malaria cases in Korea is attributed to Plasmodium falciparum and P. vivax infections, whereas P. malariae and P. ovale infections are very rare. Falciparum and ovale malaria are mostly imported from Africa, while most of the vivax malaria cases are imported from Southeast Asia. Here, we report 6 Korean imported ovale malaria cases (4 males and 2 females) who had visited in Africa during 2013-2016. These subjects were diagnosed with P. ovale based on microscopic findings, Plasmodium species-specific nested-PCR, and phylogenetic clade using 18S rRNA gene sequences. We identified 2 P. ovale subtypes, 1 P. ovale curtisi (classic type) and 5 P. ovale wallikeri (variant type). All patients were treated with chloroquine and primaquine, and no relapse or recrudescence was reported for 1 year after treatment. With increase of travelers to the countries where existing Plasmodium species, the risk of Plasmodium infection is also increasing. Molecular monitoring for imported malaria parasites should be rigorously and continuously performed to enable diagnosis and certification of Plasmodium spp.

• 한국자원식물학회:학술대회논문집
• /
• 한국자원식물학회 2000년도 The 7th International Symposium
• /
• pp.64-65
• /
• 2000

Cancer is a general term subjected to a series of malignant tumor diseases which may affect many different parts of the human body. These cancer diseases are characterized by a rapid and uncontrolled formation of abnormal cells in the body. Cancer chemotherapeutic agents can often provide the prolongation of life and occasionally cures. To date many kinds of compounds have been obtained from plants kingdom as anti-neoplastic and anti-cancerous agents. However, there is no special type of compounds for cancer therapy. In our laboratory, anti-tumor and cytotoxic screenings on higher plants collected in Japan, China, Korea, Southeast Asia and South America have been done by using Sarcoma 180 ascites in mice, P388 lymphocytic leukemia in mice, Chinese hamster lung V-79 cells, P388 cells and nasopharynx carcinoma (KB) cells. The family, Simaroubaceae consists of about 20 genera and 120 species, mainly shrubs and trees, distributed in tropical and subtropical country. Simaroubaceae is classified as RUTALES, together with Rutaceae, Burseraceae, Meliaceae, Malpighiaceae and Polygalaceae. The members differ from the Rutaceae in not containing oil glands. Bitter principles are a characteristic of the family, Simaroubaceae. The genera include Quassia (Simarouba) (40 spp.), Picrasma (Aeschrion) (6 spp.), Brucea (10 spp.), Soulamea (10 spp.), Ailanthus (10 spp.) and Perriera (1 spp.) etc.. Surinam quassia derived from Quassia amara growing in Guianas, north Brazil and Venezuela is used in traditional medicines for stomachic, anti-amoebic, anti-malarial and anti-anaemic properties. Also, various parts of a number of plants of the family Simaroubaceae have been used in traditional medicine for the treatment of a variety oi diseases including cancer, amoebic, dysentery and malaria. Then, the research has established that it is the quassinoid content of these plants that is responsible for above activities. In this meeting, I will present on anti-tumor and anti-malarial activities and their active principles of Simaroubaceae plants, Eurycoma longifolia, Ailanthus vilmoriniana, Simaba cedron and Brucea mullis which have been studied in our laboratory.