• 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.

• Parasites, Hosts and Diseases
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• 제39권4호
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• pp.323-325
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• 2001

The egg Positive rate of Enterobius vermicularis and Clonorchis sinensis of school children in the rural area was studied in Hamyang-gun, Gyeongsangnam-do in Korea. Cellotape anal swab and formalin ether concentration methods were performed one time to 720 Primary school children. The total egg Positive rate of E. vermicularis was 12.6% in two schools (Baekjeon and Wiseong). In the Baekjeon and Wiseong primary school, the egg Positive rate of E. vermicularis was 4.6% and 13.4%, respectively Pinworm egg Positive rate was 17.6% in the lower grades (1st, 2nd and 3rd), and 7.7% in higher grades (4th, 5th and 6th). The total egg Positive rate of male and female was 12.6% and 12.7%, respectively. The egg Positive rate of C. sinensis of Baekjeon and Wiseong Primary school was 1.5% and 0.46%, respectively The total e99 Positive rate of C. sinesis was 0.56%. This survey showed that continuous education and chemotherapy is necessary to treat and prevent reinfection of E. vermicularis. In the case of C. sinensis, health education for school children is recommended to prevent potential infection of adolescents.

• Parasites, Hosts and Diseases
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• 제52권1호
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• pp.105-109
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• 2014

Plasmodium falciparum malaria is a major public health problem in Thailand due to the emergence of multidrug resistance. The understanding of genetic diversity of malaria parasites is essential for developing effective drugs and vaccines. The genetic diversity of the merozoite surface protein-1 (PfMSP-1) and merozoite surface protein-2 (PfMSP-2) genes was investigated in a total of 145 P. falciparum isolates collected from Mae Sot District, Tak Province, Thailand during 3 different periods (1997-1999, 2005-2007, and 2009-2010). Analysis of genetic polymorphisms was performed to track the evolution of genetic change of P. falciparum using PCR. Both individual genes and their combination patterns showed marked genetic diversity during the 3 study periods. The results strongly support that P. falciparum isolates in Thailand are markedly diverse and patterns changed with time. These 2 polymorphic genes could be used as molecular markers to detect multiple clone infections and differentiate recrudescence from reinfection in P. falciparum isolates in Thailand.

• 한국어병학회지
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• 제27권2호
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• pp.85-89
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• 2014

Water temperature is a key environmental factor controlling the epizootics of viral diseases in fish. High water temperature is associated with the rapid spread of rock bream iridovirus (RBIV) disease and with high mortality of RBIV infected fish. Although protection of fish against iridoviral disease by active immunization has been reported, little information is available concerning whether fish survived from an epizootic of iridoviral disease can naturally acquire resistance against the viral disease. In the present study, we have demonstrated that juvenile rock bream, which survived from a natural epizootic of RBIV, acquired resistance against recurrence or reinfection of RBIV, and this resistance was established during the subsequent low water temperature period. Furthermore, the possible involvement of the adaptive humoral immune response in the resistance of the juvenile rock bream was suggested by in vivo neutralization experiment.

• 대한의생명과학회지
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• 제10권2호
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• pp.163-169
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• 2004

Worldwide, tuberculosis remains one of the leading infectious diseases, accounting for nearly 3 million deaths and more than 8 million new cases annually. DNA typing of Mycobacterium tuberculosis is important for the control of tuberculosis, since it can be used to track transmission route of tuberculosis, source of internal laboratory contaminations, and to answer questions on the nature of tuberculosis infections such as reactivation or exogenous reinfection of disease. At present, IS6110-based RFLP is the choice of method for typing large numbers of clinical isolates of M. tuberculosis, since it has the highest resolution power. However, RFLP requires long time, high cost and qualified experts, so only reference level laboratories can use the RFLP technique. In order to have an optional molecular typing method suitable for the clinical settings, this study evaluated the use of one of PCR-based typing methods, IS6110-based outward PCR for typing clinical isolates of M. tuberculosis. In brief, the results from this study showed that IS6110-based RFLP is useful to discriminate diverse clinical isolates of M. tuberculosis as well as to identify clinical isolates that belong to the same family or cluster groups that have been previously classified by RFLP analysis. In addition, the banding profiles resulted from IS6110-based outward PCR seemed to represent genomic characteristics of M. tuberculosis, since strains belong to the K-family generated unique band that is not present in any other strains but present only in the genome of K-family strains. The IS6110-based outward PCR was also shown to be useful with DNAs isolated directly from liquid cultures indicating this method can be suitable for typing M. tuberculosis in clinical settings.

• 한국어병학회지
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• 제12권2호
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• pp.107-113
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• 1999

능성어의 바이러스성 신경괴사증 바이러스(fish nodavirus)의 병원성을 능성어 및 다른 해산어류를 대상으로 인위감염법에 의해 조사한 결과, 능성어 바이러스성 신경괴사증 바이러스는 능성어에서는 소형어(27 g)부터 대형어(104 g)까지 제사를 일으켜 강한 병원성을 나타냈지만, 실험에 사용한 크기의 방어(537 g), 참돔(207 g), 돌돔(43 g), 넙치(41 g), 자주복(27 g) 및 조피볼락(94 g)에는 폐사를 일으키지 않아 병원성을 나타내지 않았다. 그리고 사육수온별 능성어에 대한 바이러스의 병원성은 수온 $15^{\circ}C$에서는 병원성을 나타내지 않았고, 수온 $20\sim28^{\circ}C$에서는 수온이 높을 수록 병원성을 강하게 나타냈다. 그리고 바이러스는 근육주사, 복강 주사 및 경구감염뿐만 아니라 침지감염과 혼합사육감염에 의해서도 쉽게 능성어에 감염이 되지만, 감염 후 생존한 능성어에 대해서는 바이러스를 재감염시켜도 폐사가 일어나지 않았다.

• Parasites, Hosts and Diseases
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• 제34권4호
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• pp.255-258
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• 1996

닭에 있어서 닭와포자충의 재감염에 대한 방어기전을 이해하기 위하여 장기간에 걸쳐 혈청IgG항체가를 경시적으로 조사하였다. 2일령의 SPF 병아리(Dekalb-Warren, Sex-Sal-Link)에 $5{\;}{\times}{\;}10^5$개 그리고 IgG가가 정상으로 복귀한 다음 10일인 340일령에 $1{\;}{\times}{\;}10^7$개의 닭와포자충의 오오시스트를 경구투여하고 나서 채혈하여 간점형광항체법을 이용하여 혈청IgG 항체가를 측정하였다. IgG 가는 감염후 3일부터 38일까지는 대조군과 차이가 없었으나 45일부터 1:21.33으로 상승하기 시작하여 120일에 1:512로 최고치에 이른다음 점점 떨어져 330일에 1:4로 정상치에 이르렀다. 도전 감염후 7, 14, 28일에 각각 1:16, 1:512, 1:1.024로서 점점 높아져 정점에 이른다음 급격히 떨어져 63일에 정상으로 복귀하였다. 한편, 대조군의 항체가는 모두 1:2~1:4의 범위에 있었으며 이 원충의 도전감염전 및 후에 있어서 분변으로부터 집충시켜 제작한 Kinyoun 항산염색표본에서도 오오시스트를 전혀 검출할 수 없었다. 분변내의 오오시스트의 소실 시기와 최초 감염에 있어서 IgG가의 피이크는 일치하지 않았다.

• Journal of Chest Surgery
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• 제35권11호
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• pp.831-834
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• 2002

감염된 심박조율기의 부분적 제거 후에 발생되는 재감염율은 51%에서 77%에 이르기 때문에 심박조율기의 어느 부위라도 감염이 된다면 모든 심박조율기의 하드웨어는 제거되어야 한다. 심폐기 가동하에서 감염된 심박조율기를 제거하는 것은 감염과 증식물의 확산 뿐만 아니라 기계적 손상을 방지 할 수 있다. 저자 등은 좌쇄골하 정맥에서 심장내로 이동된, 감염된 경정맥 심박조율기 도관에 의해 발생한 심내막염의 1예를 보고 한다. 심장내로 이동된 심박조율기 도관과 증식물이 부착된 전극은 심폐우회를 이용하여 제거하였다.

• Journal of Oral Medicine and Pain
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• 제37권2호
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• pp.75-79
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• 2012

위염 및 위암 등의 발생과 관련되어 있는 Helicobacter pylori(H. pylori)는 구강의 치태와 타액에서 주로 발견이 된다. 유년시절 동안 주로 감염되는 것으로 알려져 있지만 감염경로는 불분명하다. 구강이 H. pylori의 두 번째 서식지로서 전염경로 및 위장내 H. pylori의 제균 후 재감염에 중요한 영향을 끼칠 수 있는지는 논쟁이 되고 있다. 따라서 본 저자는 문헌고찰을 통하여 구강 내에 존재하는 H. pylori에 관하여 알아보고자 하였다. 위장에 존재하는 H. pylori는 위인두반사나 구토에 의해 구강 내 발현될 수도 있으나, 구강과 위의 감염은 서로 관련성이 없는 것으로 보고되고 있다. 진단방법으로는 혈청학적검사, 요소호기검사, 중합효소연쇄반응(polymerase chain reaction: PCR)방법, Urease검사, 조직검사 등이 있으나, 타액과 치태에서는 nested PCR 방법이 주로 추천되어 진다. 구강 내 감염율은 다양하게 나타나며, 치과질환과의 연관성은 없는 것으로 사료된다. 그러나 치주질환 환자의 구강 내에서 발현율은 높게 나타나므로, 주의가 요구되며 향균 구강세척제의 사용이 권유된다. 결과적으로 구강 내 H. pylori는 정상세균총으로 사료되며, 향후 구강내 H. pylori에 관한 추가적인 많은 연구가 필요하리라 사료된다.

• Restorative Dentistry and Endodontics
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• 제25권1호
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• pp.116-122
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• 2000

On the instrumented root canal wall, amorphous, irregular smear layer can be observed with Scanning Electron Microscope(SEM). The purpose of this study was to evaluate the effect of the presence or absence of smear layer on the adhesion of Staphylococcus aureus to the dentin of the root canal. Human incisors, extracted within 7 days, with no caries, no fracture, no calcification of canal, were selected. After cutting crown portion at cemento-enamel junction, root canal preparation was done by modified crown-down technique using Profile and Gates - Glidden Drill. During canal preparation, 10ml physiologic saline solution(group1&3) or 10ml 3.5% NaOCl(group2&4) was used as irrigation solution. And 10ml physiologic saline solution(group1&3) or 10ml 0.5M EDTA(group2&4) was applicated for final flush. After vertical sectioning and ethylene oxide gas sterilization, samples(group1&2) were immersed into BHIYHM broth inoculated with Staphylococcus aureus (ATCC 31153) and incubated for 3hrs at $37^{\circ}C$. All samples were prepared for and observed with SEM(JEOL JSM840S). The data were analyzed by Mann-Whitney rank sum test. The conclusions are as follows ; 1. Smear layer covers entire root canal surface after root canal preparation. 2. Smear layer has been removed away and the entrances of dentinal tubules have opened widely, when applying 0.5M EDTA and 3.5% NaOCl. 3. A significantly higher number of bacteria were adhered to the root canal dentin without smear layer(p<0.0001). 4. Smear layer produced during root canal preparation impedes bacterial adhesion and colonization to dentin matrix, therefore inhibits canal reinfection.