• 한국동물위생학회지
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• 제46권1호
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• pp.29-34
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• 2023

Mycobacterium tuberculosis complex (M. tuberculosis complex) is a causative agent of contagious chronic disease in a wide range of mammalian hosts, mainly cattle, goat, pigs, wildlife, and humans. The definite diagnosis of tuberculosis is made based on culture of M. tuberculosis, but it takes a long time. In the present study, we analyzed whether the detection time of M. tuberculosis could be reduced when cultured in the medium containing the culture-promoting ingredients-107 (CPI-107) using the BacT/Alert 3D system, an automatic culture system. The time to detection (TTD) tended to decrease as the added concentration of CPI-107 increase. In the case of low numbers of M. tuberculosis, it decreased by 21.0% at 1.2 mg/mL of CPI-107 and by 15.9% in the case of high numbers of M. tuberculosis. In the culture using clinically isolated M. tuberculosis strains, the shortening of the culture time by CPI was more evident. In conclusion, the detection time of M. tuberculosis was shortened in the medium added with CPI-107, and this could be used for isolation, culture and drug susceptibility test of M. tuberculosis.

• Journal of Yeungnam Medical Science
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• 제1권1호
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• pp.49-58
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• 1984

폐결핵 환자의 객담으로 부터 비정형항산균의 배균여부를 규명하기 위하여 세균학적 시험 및 임상적 조사를 시행하여 다음과 같은 결론을 얻었다. 1. 객담 334예에서 항산균 103주 (30.8%)를 분리 배양하였다. 2. 분리배양된 항산균주에서 비정형항산균으로 감별된 균주는 10주(9.7%)이며 인형결핵균주는 93주(90.3%)이였다. 3. 감별된 비저형항산균주는 Runyon군별로는 암착색균군, 광비발색균군이 각각 3주 (30.0%)씩이며 신속발육균군이 4주(40.0%)였으며 광발색균군은 분리되지 않았다. 4. 생물학석 성상 및 생화학적 특성시험 양상에 의해 암착색균군 3주 중 2주는 Mycobacterium scrofulaceum, 1주는 Mycobacterium szulgai로, 광비발색균 3주 중 2주는 Mycobacterium avium complex, 1주는 Mycobacterium terrae로 동정되였으며, 신속발육균주 4주중 3주는 Mycobacterium fortuitum, 1주는 Mycobacterium chelonei로 등정되었다. 5. 항결핵제에 대한 시험관내 약제감수성검사에서 INH, SM에서는 10주가 전부 내성을 나타내었으며, EB, TH, 및 CS의 저농도인 10mcg, 50mcg, 및 40mcg에서 완전내성을 나타내었다. 그리고 EB, TH, 및 RFP의 고농도인 20mcg, 및 100mcg,에서 감수성을 나타내었다. 6. 비정형항산균이 배균된 환자의 X-선소견 및 임상적 소견 조사에서는 인형결핵균 감성으로 인한 폐결핵 환자의 증상에 비해 경하지 않는 것으로 사료되었으며 장기간 항결핵제의 투여치로 되어 왔으나 대부분 호전되지 않았다.

• 대한수의학회지
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• 제60권2호
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• pp.85-88
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• 2020

A 12-month-old domestic rabbit died suddenly without specific clinical signs. Gross examination revealed irregular yellowish hepatic nodules with pus in the submandibular muscles, lungs, uterus, and small intestines. Histopathological examination of the liver showed granulomatous inflammation with acid-fast-positive bacteria. Mycobacterium bovis SB1040 was identified by polymerase chain reaction and spoligotyping, and Pasteurella multocida was isolated from the multiple lesions. This report demonstrates the pathological features of rare bovine tuberculosis (bTB) in a domestic rabbit, the first case in the Republic of Korea. To ensure public safety, we recommend routine monitoring of rabbits to control the incidence of bTB.

• 대한의생명과학회지
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• 제22권4호
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• pp.215-219
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• 2016

The problems of tuberculosis and its drug resistance are very severe. Therefore, rapid and accurate drug susceptibility assay is required. Recently, there has been an increased understanding of the genetic mechanism of Mycobacterium tuberculosis (MTB) drug resistance as well as advancement of molecular technologies. While many gene mutations correlate well with drug resistance, many genes do not show a strong correlation with drug resistance. For this reason, the current study assessed the utility of rpoB mRNA as a target to detect live mycobacteria. In this study, RT-PCR targeting of rpoB mRNA in BCG treated with rifampin was performed. Conventional RT-PCR and real-time PCR targeting rpoB mRNA as well as 85B mRNA was performed to determine whether these two methods could distinguish between viable and non-viable MTB. The levels of rpoB and 85B mRNA detected by RT- PCR were compared in parallel with colony forming unit counts of BCG that were treated with rifampin for different periods of time. The data suggests that that even though both mRNA levels of rpoB and 85B decreased gradually when rifampin-treatment increased, the rpoB mRNA seemed to represent live bacteria better than 85B mRNA. This study clearly indicates that RT-PCR is a good method to monitor viable cell counts in the liquid culture treated with the anti-tuberculosis drug.

• 대한수의학회지
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• 제48권2호
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• pp.181-185
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• 2008

Comparative studies of histopathologic lesions from 23 purified protein derivative (PPD) positive cattle, 21 slaughter cattle found with tuberculosis, and 11 tuberculosis-positive elk (Cervus elaphus) were performed. PPD positive cattle did not show specific histopathologic lesions in all 23 heads that were no visible lesion reactor. Slaughter cattle found with tuberculosis revealed microscopically classical granulomatous lesion (tubercle) with central caseous necrosis surrounded by mantle of epithelioid cells and Langhan's giant cells capsuled by connective tissue in lung. Elk was noted with some different lesion patterns with classical granulomatous lesion and suppurative abscesses that was composed of fibrin, degenerated cells without having connective tissue. In addition, many Langhan's giant cells infiltration in alveoli at peripheral lesion were observed in some cases of classical granulomatous lesion and suppurative abscesses.

• Bulletin of the Korean Chemical Society
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• 제33권12호
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• pp.4074-4078
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• 2012

The first step in the common pathway for the biosynthesis of branched chain amino acids is catalyzed by acetohydroxyacid synthase (AHAS). The AHAS is found in plants, fungi and bacteria. With an aim to identify new anti-tuberculosis drugs that inhibit branched chain amino acid biosynthesis, we screened a chemical library against Mycobacterium tuberculosis AHAS. The screening identified four compounds, AVS 2087, AVS 2093, AVS 2236, and AVS 2387 with $IC_{50}$ values of 0.28, 0.21, 3.88, and $0.25{\mu}M$, respectively. Moreover, these four compounds also showed strong inhibition against reconstituted AHAS with $IC_{50}$ values of 0.37, 0.26, 1.0, and $1.18{\mu}M$, respectively. The basic scaffold of the AVS group consists of 1-pyrimidin-2-yl-1H-[1,2,4]-triazole-3-sulfonamide. The most active compound, AVS 2387, showed the lowest total interaction energy -8.75 Kcal/mol and illustrates its binding mode by hydrogen bonding with $H_{\varepsilon}$ of Gln517 with the distance of $2.24{\AA}$.

• 대한미생물학회지
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• 제34권6호
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• pp.555-559
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• 1999

The 38 kDa protein of Mycobacterium tuberculosis, which was known previously as antigen 5, has been extensively used in the serodiagnosis of tuberculosis. In an attempt to develop and evaluate a serodiagnostic test using the antigen, we expressed the 38 kDa protein in BCG and its seroreactivity was compared to that expressed in Escherichia coli. The coding region of the 38 kDa protein was amplified by PCR, and the gene was cloned into a Mycobacterium-E. coli shuttle expression vector pYMC-his and pQE30 expression vector and expressed in BCG and E. coli, respectively. Both recombinant 38 kDa proteins showed strong seroreactivity against pooled serum from tuberculosis patients. There was no significant difference in seroreactivity between the two recombinant antigens in sera from the far advanced tuberculosis patients. However, of 25 tuberculosis patients graded as "minimal" by chest X-ray, 5 (20.0%) were seropositive by r38 kDa expressed in E. coli, while 8 (32.0%) by that expressed in BCG. Likewise, higher seroreactivity by r38 kDa expressed in BCG was found in sera from the moderately advanced tuberculosis. This study thus indicates that the recombinant 38 kDa expressed in BCG is more effective than that expressed in E. coli in detecting antibodies to the native 38 kDa protein of M. tuberculosis in sera from minimally affected tuberculosis patients.

• Tuberculosis and Respiratory Diseases
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• 제85권3호
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• pp.264-272
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• 2022

Background: The current conventional drug susceptibility test (DST) for Mycobacterium tuberculosis (Mtb) takes several weeks of incubation to obtain results. As a rapid method, molecular DST requires only a few days to get the results but does not fully cover the phenotypic resistance. A new rapid method based on the ability of viable Mtb bacilli to hydrolyze fluorescein diacetate to free fluorescein with detection of fluorescent mycobacteria by flow cytometric analysis, was recently developed. Methods: To evaluate this cytometric method, we tested 39 clinical isolates which were susceptible or resistant to isoniazid (INH) or rifampin (RIF), or ethambutol (EMB) by phenotypic or molecular DST methods and compared the results. Results: The susceptibility was determined by measuring the viability rate of Mtb and all the isolates which were tested with INH, RIF, and EMB showed susceptibility results concordant with those by the phenotypic solid and liquid media methods. The isolates having no mutations in the molecular DST but resistance in the conventional phenotypic DST were also resistant in this cytometric method. These results suggest that the flow cytometric DST method is faster than conventional agar phenotypic DST and may complement the results of molecular DST. Conclusion: In conclusion, the cytometric method could provide quick and more accurate information that would help clinicians to choose more effective drugs.

• Tuberculosis and Respiratory Diseases
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• 제85권3호
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• pp.256-263
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• 2022

Background: Mycobacterium tuberculosis (Mtb) is resistant to the β-lactam antibiotics due to a non-classical transpeptidase in the cell wall with β-lactamase activity. A recent study showed that meropenem combined with clavulanate, a β-lactamase inhibitor, was effective in multidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis (TB). However, in Korea, clavulanate can only be used as drugs containing amoxicillin. In this study, we investigated the susceptibility and genetic mutations of drug-resistant Mtb isolates to amoxicillin-clavulanate and meropenem-clavulanate to improve the diagnosis and treatment of drug-resistant TB patients. Methods: The minimum inhibitory concentration (MIC) of amoxicillin-clavulanate and meropenem-clavulanate was examined by resazurin microtiter assay. We used 82 MDR and 40 XDR strains isolated in Korea and two reference laboratory strains. Mutations of drug targets blaC, blaI, ldtA, ldtB, dacB2, and crfA were analyzed by polymerase chain reaction and DNA sequencing. Results: The MIC₉₀ values of amoxicillin/clavulanate and meropenem/clavulanate in drug-resistant Mtb isolates were 64/2.5 and 16/2.5 mg/L, respectively. Gene mutations related to amoxicillin/clavulanate and meropenem/clavulanate resistance could not be identified, but T448G mutation was found in the blaC gene related to β-lactam antibiotics' high susceptibility. Conclusion: Our results provide clinical consideration of β-lactams in treating drug-resistant TB and potential molecular markers of amoxicillin-clavulanate and meropenem-clavulanate susceptibility.

• 한국동물위생학회지
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• 제30권4호
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• pp.527-532
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• 2007

In present study, we described the reliability of the dual priming oligonucleotide (DPO) multiplex polymerase chain reaction (PCR) for the detection of Mycobacterium tuberculosis complex (MTC) and non-Mycobacterium tuberculosis (NMT) in blood samples of the Korea native cattle, Hanwoo. Among 340 samples 22 (6.5%) were positive in using DPO multiplex PCR, 21 (6.2%) were positive in PCR. The relative agreement between 2 tests was 99.7%, and the agreement quotient (kappa), was 0.95 (excellent). In these results, we demonstrated the successful application of DPO multiplex PCR for the diagnosis of bovine tuberculosis in Hanwoo. Multiplex PCR, using DPO primers, can be useful for the simple diagnosis of bovine tuberculosis in bovine blood samples.