• 대한수의학회지
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• 제41권1호
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• pp.89-98
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• 2001

This study was conducted to detect the toxoplasma specific-DNA in circulating blood and organs collected from slaughtered pigs at slaughtering house and experimentally infected pigs with Toxoplasma gondii tachyzoites by polymerase chain reaction(PCR), and also PCR was applied to diagnose for acute phase of swine toxoplasmosis as a newly developed diagnostic test. The sensitivity of oligonucleotide primer, T-1 & T-2, designed from toxoplasma B1 gene amplification method was compared with Tp parasite detection by mouse inoculation(MI). On the other hand, latex agglutination test(LAT) was conducted to detect the serum antibodies comparing with the detection of toxoplasma by PCR and MI. The results obtained were summarized as follows. PCR was able to determine at the lowest level of $10^0/ml$ T. gondii in blood samples which were blended with a serial diluted T gondii in vitro. On the other hand, $10^2/5g$ of T gondii could detect from a variety of tissues including lung, diaphragm, liver, heart, spleen and brain in vitro. The primer was proved to specifically determine T gondii in blood and tissues in vitro but it did not detect Neospora caninum used as a negative control. DNA of T. gondii was effectively extracted by freezing, thawing and grinding twice both tissues mixed with T gondii in vitro and in experimentally infected pig's tissues. PCR detected specific DNA in the blood of experimentally infected pigs at 108 hrs and 120 hrs post-infection, it was the same time that the pigs showed fever and parasitaemia. In case of tissue, specific DNA was, however, detected only lung from experimentally infected pigs. Even though the duration of acute phase was from 3 to 7 days post-infection, but the latex agglutination test (LAT) results appeared from 8 days post-infection. A comparison of sensitivity in determining T gondii in blood samples between PCR and MI, PCR positive rate ranged from 25 to 33.3%, but that of MI covered from 75 to 100%.

• 동의생리병리학회지
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• 제22권1호
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• pp.96-99
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• 2008

Toxoplasma gondiiis a widespread apicomplexan parasite which is able to infect virtually all warm-blooded vertebrates. Twenty-two percent of the U.S. population is infected, but severe disease in adults is mainly limited to immunosuppressed patients. In patients with acquired immunodeficiency syndrome(AIDS), T. gondii causes a life-threatening opportunistic infection, with Toxoplasma encephalitis as its most severe manifestations. T. gondii is also known to cause congenital infection and is among the pathogens with the highest incidence of complications in pregnancies. Despite its clinical importance, only very few therapeutic drugs against T. gondii are available, all of which target the rapidly dividing tachyzoites, leaving the dormant encysted bradyzoite stage unaffected. We searched 15 traditional medicines that have anti-inflammatory effect from dongyibogam and Traditional Chinese medicine. In vitro studies were performed with HeLa cell cultures, with quantification of Toxoplasma growth by a cell proliferation assay. The result of experiment shows the selectivity of Citrus unshiu Markovich is 6.0. This is higher than sulfadiazine (selectivity was 1.63). For in vivo studies, mice were acutely infected intraperitoneally with $10^5$ tachyzoites of the virulent RH strain and then treated per orally for 4 days from 6 hours postinfection. Efficacy was assessed by sequential determination of parasite burdens in peritoneal cavity. In vivo, Citrus unshiu Markoviche inhibited Toxoplasma growth at a concentration of 10㎎/㎏ of body weight per day, the inhibition ratio was estimated to be 64.01%.

• Parasites, Hosts and Diseases
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• 제56권3호
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• pp.237-245
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• 2018

Toxoplasma gondii can infect all the vertebrates including human, and leads to serious toxoplasmosis and considerable veterinary problems. T. gondii heat shock protein 60 (HSP60) is associated with the activation of antigen presenting cells by inducing initial immune responses and releasing inflammatory cytokines. It might be a potential DNA vaccine candidate for this parasite. A pVAX-HSP60 DNA vaccine was constructed and immune responses was evaluated in Kunming mice in this study. Our data indicated that the innate and adaptive immune responses was elicited by successive immunizations with pVAX-HSP60 DNA, showing apparent increases of CD3e+CD4+ and CD3e+CD8a+ T cells in spleen tissues of the HSP60 DNA-immunized mice ($24.70{\pm}1.23%$ and $10.90{\pm}0.89%$, P<0.05) and higher levels of specific antibodies in sera. Furthermore, the survival period of the immunized mice ($10.53{\pm}4.78day$) were significantly prolonged during the acute T. gondii infection. Decrease of brain cysts was significant in the experimental group during the chronic infection (P<0.01). Taken together, TgHSP60 DNA can be as a vaccine candidate to prevent the acute and chronic T. gondii infections.

• Parasites, Hosts and Diseases
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• 제49권3호
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• pp.207-212
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• 2011

Rapid serodiagnostic methods for Toxoplasma gondii infection in cats are urgently needed for effective control of transmission routes toward human infections. In this work, 4 recombinant T. gondii antigens (SAG1, SAG2, GRA3, and GRA6) were produced and tested for the development of rapid diagnostic test (RDT). The proteins were expressed in Escherichia coli, affinity-purified, and applied onto the nitrocellulose membrane of the test strip. The recombinant SAG1 (rSAG1) showed the strongest antigenic activity and highest specificity among them. We also performed clinical evaluation of the rSAG1-loaded RDT in 182 cat sera (55 household and 127 stray cats). The kit showed 0.88 of kappa value comparing with a commercialized ELISA kit, which indicated a significant correlation between rSAG1-loaded RDT and the ELISA kit. The overall sensitivity and specificity of the RDT were 100% (23/23) and 99.4% (158/159), respectively. The rSAG1-loaded RDT is rapid, easy to use, and highly accurate. Thus, it would be a suitable diagnostic tool for rapid detection of antibodies in T. gondii-infected cats under field conditions.

• Parasites, Hosts and Diseases
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• 제57권2호
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• pp.83-92
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• 2019

Based on the reactive oxygen species (ROS) regulatory properties of diphenyleneiodonium (DPI), we investigated the effects of DPI on host-infected T. gondii proliferation and determined specific concentration that inhibit the intracellular parasite growth but without severe toxic effect on human retinal pigment epithelial (ARPE-19) cells. As a result, it is observed that host superoxide, mitochondria superoxide and $H_2O_2$ levels can be increased by DPI, significantly, followed by suppression of T. gondii infection and proliferation. The involvement of ROS in anti-parasitic effect of DPI was confirmed by finding that DPI effect on T. gondii can be reversed by ROS scavengers, N-acetyl-L-cysteine and ascorbic acid. These results suggest that, in ARPE-19 cell, DPI can enhance host ROS generation to prevent T. gondii growth. Our study showed DPI is capable of suppressing T. gondii growth in host cells while minimizing the un-favorite side-effect to host cell. These results imply that DPI as a promising candidate material for novel drug development that can ameliorate toxoplasmosis based on ROS regulation.

• Parasites, Hosts and Diseases
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• 제59권1호
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• pp.9-14
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• 2021

Toxoplasma gondii seroprevalence have been rapidly increasing in some parts of Korea. We analyzed prevalence of anti-Toxoplasma gondii antibodies, using a rapid diagnostic test (RDT), in the sera of 552 residents in Ganghwagun, 661 ones in Cheorwon-gun, and 305 ones in Goseong-gun, Korea in 2019. IgG/IgM RDT mounted with recombinant fragment of major surface antigen (SAG1), glutathione-S-transferase-linker-SAG1A, were applied to the sera. IgG seroprevalence was 28.1% in Ganghwa-gun, 19.5% in Cheorwon-gun and 35.7% in Goseong-gun. Odds ratios comparing Cheorwon vs Ganghwa was 0.63 (P=0.001) and Goesong versus Ganghwa was 1.47 (P=0.01) adjusting age and sex. Goseong had highest seroprevalence among the 3 counties both in crude rates and logistic regression. Although Cheorwon and Goseong are adjacent to the demilitarized zone (DMZ) in Korea, seroprevalence rate was much higher in Goseong. Further investigation on other DMZ-closed areas is necessary whether they have high prevalence rates compared to the other areas. T. gondii prevalence in Korea is still persists; proper health policy should be established.

• Parasites, Hosts and Diseases
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• 제30권2호
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• pp.83-90
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• 1992

Toxoplasma증의 혈청학적 진단에 있어서 민감도를 증가시키기 위해 간접 latex 응집반응의 결과와 비교하면서 ELISA를 개발하였으며, 뇌척수액의 검사 시료로서의 가능성을 검토하였다. 아울러 중추신경계 질환환자로부 터기생충질환을 감별하기 위하여 1986년부터 1991년까지 전국 카 병원에서 채취한 혈청과 뇌척수액에 대하여 간접 latex 응집반응(ILA)과 ELISA를 실시하여 Toxoplasma 항체 보유 양상을 비교 검토하였다. 전체 2,016 건의 혈청에 대해 ILA를 실시하여 76건(3.8%)의 양성 (1:32이상의 titer)을 얻었다. 그러나 양성 혈청환자에서 채취한 뇌척수액에서는 낮은 titer의 반응은 있었으나 양성은 나타나지 않았다. 이들 양성 혈청의 양성 혈청 및 음성 혈청에 대하여 ELISA로 항체검사를 실시한바 ILA의 titer가 1 : 32인 군에서 통계적으로 유의한 차이를 나타내는 항체값을 얻었으며, 그 흡반도는 0.40이었다. 뇌척수액에 대한 ELISA로는 ILA의 1 : 64 titer군에서 통계 적으로 유의한 차이가 나타났고 그때의 흡광도 0.27을 양성 판단의 기준으로 사용하였다. ELISA에 의한 항체 검사상 전체 혈청에서 7.0%의 양성을 검출하여 ILA보다 약 2배 정도의 높은 민감도를 보였으며, 뇌척수액에서 는 5.6%의 양성률을 보여 ELISA는 뇌척수액에서의 항체 검출시 유용한 방법이라고 판단하였다. ILA에 비하여 ELISA는 약 2배 정도 높은 양성률을 내었고 양성률은 나이에 마라 40대 이후 급격한 증가를 보였으며, 여성보 다는 남성에서 약 2배 정도 양성률이 높게 나타났다. ELISA에 의한 뇌척수액의 항체 검사에서는 양성률의 성별 차이를 나타내지 않았다. 이상의 결과로 판단할 때, ELISA가 ILA보다 Toxoplasma 항체 검출의 민감도가 높았으며, 뇌척수액은 ELISA의 좋은 검사시료가 되며, 특히 중추신경계 Tocxoplnsma증의 진단에 있어 뇌척수액에 대한 항체 검사에서 ELISA가 유용하다고 판단하였다.

• Parasites, Hosts and Diseases
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• 제34권2호
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• pp.135-142
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• 1996

톡소포자충(Toxoplosma gondii) 주요막단백질의 하나인 30 kDa 단백질(p30)의 항원부위를 결정하고자 p30의 아미노산 분석에 따른 친수성 부위 및 혐수성 부위에 맞게 유전자를 증폭하고 발현시켜 항원성을 검토하였다 p30의 절편으로는 p30 전체 p30의 N-말단 Signal Sequence와 C- 탈단의 혐수성 부위를 제거한 S28. S28의 N-말단 2/3부위인 Al9. S28의 C-말단 2/3부위인 Pl9. 528의 N-탈난 1/3부위인 X9 중앙 1/3부위인 Y10 및 C-말단 1/5부위인 Z9로 구성하였다. 각절편에 대한 primer에는 EcoR I의 clampsequence를 포함시켜 중합효소반응으로 증폭시켰으며 G57를 발현하는 pGEX-4T-1 vector에 삽입시킨 후 Eschericha coli(.JM105 strain)에 형질변형시키고 IgG로 각 절편이 GST와 융합단백질로 발현되도록 하였다 SDS-PAGE상에서 p30은 63 kDa. S28는 54 kDa Al9과 Pl9은 각각 45 kDa. X9은 35 kDa. Y10은 36 kDa 및 29은 35 kDa 단백질로 발현되었다. 각각의 단백질은 westemblot상에서 GSTdetectionkit와 잘 반응하여 융합단백질임을 확인하였다. 톡소포자충증 환자 혈청과 westem blot에서 p30. S28 및 Al9은 반응하여 항원성이 인정되었으나 Pl9 . X9, Y10 및 Z9는 반응하지 않았다 따라서. p30의 중간 1/3 부위의 존재하에 N-말단 1/3부위가 항원성을 나타내는 구조적 항원이거나. 첫 1/3부위와 중 간 1/3부위의 경계에 위치한 polypeptide가 항원성을 발현하는 것으로 추정되었다.

• 대한수의학회지
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• 제31권4호
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• pp.491-500
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• 1991

This study was conducted to detect the serum antibodies in the experimentally toxoplasma infected dogs and street dogs by use the of an enzyme-linked immunosorbent assay (ELISA). And this test was performed on the polystylene microplate by coating with the tachyzoites soluble antigen of T gondii (RH strain), incubated with sera diluted then, added with HPO-conjugated rabbit anti-dog IgG and o-phenylenediamine used as a substrate. Tachyzoites of T gondii harvested from mouse peritoneal cavity were purified by 30, 40 and 50% Percoll density gradient centrifugation and used as the source of antigen. The results obtained were summarized as follows; 1. The highest ratio of positive to negative (P/N ratio) was obtained at the level of $l{\mu}g/ml$ protein concentration of antigen with the 1/4000 dilution of the conjugate measured by checker-board titration. It was regarded as the optimum concentration of the antigen and conjugate. 2. Cut-off value in this IgG ELISA was 0.375 that was determined by mean absorbance (at 492nm) of IFA negative serum added with the dauble value of the standard deviation $(mean{\pm}2S.D.)$. 3. Serum ELISA IgG antibodies to T gondii in the exyerimentally infected dogs were detected firstly at the Week 3 after inoculation and the highest titer was recognized at the Week 4, 5 and 6 after inoculation. 4. Stability of the antigen absorbed in the microplates that were preserved at $4^{\circ}C$ and $-25^{\circ}C$ separately were prolonged up to 3 weeks and 10 weeks at $4^{\circ}C$ and $-25^{\circ}C$, respectively. However the reproducibility was not reliable after the preservation of 4 weeks and longer. 5. Positive rate of the specific antibodies in 312 test sera was 28.5% and there was no significant differences between the male (27.8%) and female (29.5%), respectively. 6. The IgG ELISA was proved to be a specific procedure for the detection of antibodies to canine toxoplasma infection and also evaluated as a screening test for the large scale of test samples in laboratory.

• Clinical and Experimental Pediatrics
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• 제52권5호
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• pp.622-626
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• 2009

키쿠치(Kikuchi) 병, 키쿠치-후지모토(Kikuchi-Fujimoto) 병, 혹은 조직구 괴사성 림프선염은 1972년 일본에서 키쿠치와 후지모토 두 사람에 의해 처음 기술되었으며 흔히 아시아 지역에서 30세 미만의 여성들을 주로 침범하는 자가 관해 질환으로 기술되어져왔다. 이 질환의 병인은 여전히 잘 알려져 있지 않으나 감염성(EBV, HHV-6 and -8, HTLV-1, cytomegalovirus, varicella-zoster virus, tuberculosis, toxoplasmosis, yersiniosis, cat scratch disease), 자가면역성(SLE, Kawasaki disease), 그리고 종양성 질환(lymphoma)이 포함되는 것으로 간주된다. 가장 흔한 임상증상은 발열과 통증 없는 경부 림프선염이다. 진단은 생검을 통한 조직병리학적으로 하게 되는데, 주로 풍부한 핵파괴(karyorrhexis)를 가진 피질 주위 지역에서 나타나는 국소 괴사, 괴사 지역 주위로 비정형적인 단핵구들의 집합, 중성구 및 형질 세포의 결핍, 그리고 대개 림프절 캡슐의 보존 등으로 특징 지워진다. 절대적인 치료법은 없어 대증 치료를 하게 되며 치료 없이도 대개 1-6개월 안에 자가 관해되고 재발률도 3.3%에 불과하다. 키쿠치-후지모토 병의 합병증으로 피부, 심장, 골수 등을 침범할 수 있으며 간질환, 무균성 뇌수막염, 간비비대 등이 발생할 수 있으나 드물다. 본 증례에서는 입원 당시 결핵성 임파선염과 뇌수막염으로 오인되었던 무균성 뇌수막염을 동반한 키쿠치-후지모토 병을 경험하였기에 이에 보고하는 바이다.