• 대한바이러스학회지
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• 제26권2호
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• pp.235-244
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• 1996

Rickettsia tsutsugamushi의 원형균주인 Karp주와 Gilliam주를 초대 배양된 사람 정상 2배체 폐세포(LuMA cell)를 이용하여 증식과 세포병변들의 속도를 비교할 수 있었고, 배양된 균주는 네스티드 프라이머를 사용하여 혈청형을 동정할 수 있었다. R. tsutsugamushi의 세포벽 외막에 존재하며 혈청형을 결정하는 주요항원은 54-56Kd 단백인 것으로 밝혀지고 있는데, 이 단백 유전자의 DNA 염기서열을 분석하여 Karp주와 Gilliam주의 공통서열로 첫번째 프라이머쌍을 만들었고 첫번째 프라이머쌍의 안쪽에 위치한 혈청형 사이에 차이가 있는 서열로 두번째 프라이머쌍을 만들었다. 네스티드 뉴클레오티드 프라이머는 중합효소 연쇄반응의 특이성을 증가시킬 수 있는데 이 실험 결과로 이 PCR 방법은 scrub typhus의 진단과 혈청형의 동정에 적용될 수 있을 것으로 보여진다.

• 대한바이러스학회지
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• 제28권2호
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• pp.193-201
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• 1998

In Sprague Dawley (SD) rats, antibodies against strains of Orientia tsutsugamushi, Kato, Karp and Gilliam, were produced in order to investigate their longevity and cross-reactivities to their corresponding homologous and heterologous antigens. By immunofluorescence assay (IFA) of IgG and IgM, it was shown that the immunity to the homologous strains persisted at a higher level (longevity of at least 34 weeks with higher IFA titers). On the other hand, the immunity to the heterologous strains persisted at a lower level (longevity of 10 to 34 weeks with lower IFA titers). Since infection with one strain of O. tsutsugamushi does not preclude reinfection with other strains, understanding of the antigenic diversity of O. tsutsugamushi and duration of the immunity to both homologous and heterologous strain is very important in diagnosis of scrub typhus.

• 대한미생물학회지
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• 제35권1호
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• pp.61-68
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• 2000

Among wild chipmunks, Tamias sibiricus, captured in Kyunggi and Kangwon province in Korea, 1997, seropositivity for Orientia tsutsugamushi was determined. Serological test for Orientia tsutsugamushi infection was performed using indirect immunofluorescent antibody technique (IFA). Of 243 wild chipmunks, 61 against Gilliam strain and 64 against Karp strain of Orientia tsutsugamushi were IFA positive. Seropositivity against Gilliam strain was shown 33.3% in Kyunggi and 23.5% in Kangwon province, and against Karp strain was shown 33.3% and 25.4%, respectively.

• 대한수의학회지
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• 제44권2호
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• pp.241-249
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• 2004

As a part of epidemiologic investigation of tsutsugamushi disease, the wild rodents which were captured in Gyeongnam area were diagnosed with indirect immunofluorescent antibody assay (IFA) and Polymerase Chain Reaction (PCR) to find if they have an antibody against Orientia tsutsugamushi. The conclusion was drawn as followings. (1) The captured 58 wild rodents showed that the subspecies distribution of Apodemus agrarius was 86.2%, Microtus fortis was 8.6% and Crocidura lasiura was 5.2%. (2) The antibody positive rate of O. tsutsugamushi Gilliam, Karp, Karto and Boryong by IFA method was 32.0% in Apodemus agrarius among 50 wild rodents and 40.0% in Microtus fortis among 5 wild rodents, respectively. It was negative in the case of all the 3 Crocidura lasiura. (3) The antibody titers on Apodemus agrarius, Microtus fortis and Crocidura lasiura against Gilliam, Karp, Karto and Boryong were measured between 1:20 and 1:640. The antibody titer against each antigen was in the order Boryong>Gilliam>Karp. (4) O. tsutsugamushi was detected from the blood, spleen and kidney from the artificially infected mice by IFA and PCR. IFA showed the positive response between 3 and 18 days after inoculation. On the other hand, positive response was found from all the samples by PCR. (5) From PCR of the genomic DNA extracted from the blood, spleen and kidney samples of the captured wild rodents, Boryong-specific amplification product with size of 210 bp, which is particular in Boryong, was detected from spleen and kidney samples, but not detected in the blood. (6) Boryong-specific amplification product was detected from spleen and kidney samples which were obtained at 3, 6, 12, 18 and 24 days after the infection with Boryong. But, it wasn't detected from the uninfected samples. (7) From PCR of spleen and kidney samples of the captured wild rodents, it was found that positive rate of O. tsutsugamushi in Apodemus agrarius and Microtus fortis were 25.0% (4/16) and 20.0% (1/5), respectively. From the above results, it can be concluded that Apodemus agrarius resided in Gyeongnam area carried O. tsutsugamushi and PCR method might be a simple, precise, rapid and useful diagnostic tool than IFA for the diagnosis of O. tsutsugamushi.

• Nuclear Engineering and Technology
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• 제54권6호
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• pp.2004-2010
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• 2022

Quantification of sensitive material is of vital importance when it comes to the movement of nuclear fuel throughout its life cycle. Within the electrorefiner vessel of electrochemical separation facilities, the task of quantifying plutonium by neutron analysis is especially challenging due to it being in a constant mixture with curium. It is for this reason that current neutron multiplicity methods would prove ineffective as a safeguards measure. An alternative means of plutonium verification is investigated that utilizes the (𝛼,n) signature that comes as a result of the eutectic salt within the electrorefiner. This is done by utilizing the multiplicity variable a and breaking it down into its constituent components: spontaneous fission neutrons and (𝛼,n) yield. From there, the (𝛼,n) signature is related to the plutonium content of the fuel.

• Parasites, Hosts and Diseases
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• 제29권2호
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• pp.181-188
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• 1991

최근 전국적으로 높은 이환률을 보이고 있는 쭈쭈가무시병에 대한 방제 대책이 시급한 현실에 반해 본 질병에 대한 연구가 거의 이루어져 있지 않기 때문에 저자들은 1989년 7월부터 1950년 9월까지 9개 지역에서 숙주동물에 대한 역학적 조사를 실시하여 다음과 같은 결과를 얻었다. 1. 모두 794개의 Sherman식 live trap을 설치하여 111마리의 들쥐로 포획하여 trapping rate가 평균 14.0%이었다. 계절별로 보면 봄, 여름, 가을에 각각 11.7%, 11.2%, 12.8%이었고 겨울에는 24.0%로 가장 높았다. 포획한 111마리 중 103마리가 등줄쥐 (Apodemus agrarius)로 92.8%를 차지하여 우점종이었고, 땃쥐 (Crocidura Zasiura)가 7마리로 6.3%이었으며. 갈밭쥐 (Microtns fortis)는 1마리가 채집되어 0.9%이었다. 들쥐의 털진드기 기생률을 보면, 등줄쥐의 경우 103마리 중 84마리로 81.6%이었고, 땃쥐의 경우 7마리 중 2마리로 28.6%이었다. Chigger index는 등줄쥐의 경우 43.0개체였고 만취는 0.9개체였다. 2. 등줄쥐 혈청의 Rickettsia tsutsugamushi 항체 양성률을 보면 평균 41.8%이었는데, 조사 지역에 따라 큰 차이가 있어 고양군 도래 5리 54.9%, 고양군 고양리 20%, 고양군 원홍 2리 28.6%, 청인군 시목리 40%이었고 고양군 행신 1리, 파주군 광탄 3리 와 예산군 덕산리에서는 모두 음성이었다. 땃쥐의 경우는 7마리 모두 음성이었다. 동일 장소에서의 등줄쥐 혈청의 R. tsutsugamushi 항체 양성률의 계절적 변동은 11월부터 3웜까지는 평균 75.8%이었는데 4일에는 30.3%로 감소하였고 5월부터 8월에 걸쳐 평균 13.3%로 크게 감소하였다. 조사한 모든 양성 혈청의 항체가를 보면 Karp, Gilliam및 Kato 주에 대해 서로 교차반응을 나타냈는데 Karp주와 Kato 주 간에 보다 강한 교차반응을 보였다. 3. 총 94마리의 등줄쥐로부터 마우스 복강접종법과 간접 면역형광법으로 R. tsutsugamushl치 분리를 시도한 바 3마리에서 분리되어 감염률은 3.2%이었다.

• 한국동물위생학회지
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• 제26권3호
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• pp.203-214
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• 2003

Scrub typhus and murine typhus are common endemic febrile illness in the fall in Korea. Scrub typhus is caused by Orientia tsutsugomushi, murine typhus is caused by Rickettsia typhi. Trombiculid mites are known as both the vector and the reservoir host of O tsutsugamushi, the mites which transmit O tsutsugomushi have been reported to be Leptotrombidium pallidum and L scutellare. The author carried out an epidemiological study of scrub typhus and murine typhus in Kyodong-Myeon, Kanghwa-Gun, Incheon in relation to the residents and the host rodents, such as their distribution, seroepidemiology, and population density of chigger mites. 1. Out of 900 residents, 33(3.7%) showed positive reaction to O tsutsugamushi, 24(2.7%) to R typhi. 2. In the seropositives to O tsutsugamushi or R typhi, between the sixties and the seventies of the age were dominant. 3. In the seropositives to O tsutsugamushi serotypically Gilliam was dominant. 4. Among the total 42 field rodents trapped by the sherman traps, 18 rodents were Apodemus agrarius(42.9%), 13 rodents were Crocidura lasiura(31.0%), 5 rodents were Musmusculus(11.9%), 2 rodents(4.8%) were Crocidura suaveolens, Rattus norvegicus, Tscherskia triton, respectively. 5. Out of 42 field rodents, 25 were parasitized by 4,419 chigger mites, showing 59.5% of the infestation rate and 98.8 of the chigger index. L pallidum parasitized in A agrarius, C lasiura, M musculus, R norvegicus and T triton, and L scutellare parasitized only C lasiura. 6. Antibodies in the sera of field rodents against O tsutsugamushi and R typhi were investigated by indirect immunofluorescent antibody technique. Positive rate of antibody against O tsutsugamushi were 11.9(5 of 42) and all of the positive is A agrarius. Antibody against R typhi was not detected. These results might provide the basic information for the management of scrub typhus and murine typhus in Kyodong-myeon, where the epidemiological studies on scrub typhus and murine typhus was not carried out enough.