• Journal of Life Science
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• v.17 no.3 s.83
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• pp.435-443
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• 2007

Antimicrobial susceptibility test of the 116 strains of Mycoplasma pneumoniae isolates were performed by a broth micro-dilution method against to moxifloxacin, levofloxacin, sparfloxacin, ofloxacin, ciprofloxacin, clarithromycin minocycline, erythromycin, josamycin, and tetracycline. The initial-minimum inhibitory concentration (I-MIC) was evaluated as the lowest concentration of antimicrobial agents that prevented a color change in the medium at that time when the drug-free growth control, about 7 days after incubation, and the final-minimum inhibitory concentration (F-MIC) was defined a color change about 14 days after incubation. The evaluation to the drug-resistant M. pneumoniae isolates were determined the $MIC{\pm}1.0$ ${\mu}g/ml$ of each antimicrobial agent. According to the I-MIC, single drug-resistant M. pneumoniae strains to ciprofloxacin, ofloxacin, clarithromycin and erythromycin were 79.3, 53.5, 10.3, and 7.8%, respectively. Two kinds of drug-resistant M. pneumoniae strains to ofloxacin and ciprofloxacin, or ciprofloxacin and clarithromycin were 42.2 and 9.5%. Three kinds of drug-resistant M. pneumoniae strains to erythromycin, ofloxacin, and ciprofloxacin, or ofloxacin, ciprofloxacin and clarithromycin were 6.9 and 6.0% . According to the F-MIC, single drug-resistant M. pneumoniae strains to tetracycline, ciprofloxacin, ofloxacin, minocycline,erythromycin, josamycin, clarithromycin and sparfloxacin were 91.4, 91.4, 91.4, 89.7, 68.1, 52.6, 28.5, and 11.2%, respectively. The incidence of two kinds of drug-resistant M. pneumoniae strains were from 20.7% to 91.4%, three kinds of drug-resistant M. pneumoniae strains were from 28.5% to 89.7%, four kinds of drug-resistant M. pneumoniae strains were 2.6%, five kinds of drug-resistant M. pneumoniae were from 2.6% to 21.6%, six kinds of drug-resistant M. pneumoniae strains were from 0.9% to 24.1%, seven kinds of drug-resistant M. pneumoniae strains were from 0.9% to 2.6%, and eight kinds of drug-resistant M. pneumoniae strains were 1.7%. These results suggest that sparfloxacin, moxifloxacin and levofloxacin might be promising antimicrobial agents for the treatment of M. pneumoniae infection in Korea. However, most strains of M. pneumoniae isolates were single or multi-resistance pattern to the other tested antimicrobial agents. Therefore, tetracycline, minocycline, erythromycin, clarithromycin, and second-generation quinolones are more carefully used to patients with M. pneumoniae infection in Korea.

• The Journal of the Korean dental association
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• v.11 no.10
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• pp.667-670
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• 1973

It has been studied over 500 cases of hypnotic susceptibility test and among them performed 15 cases of periodontal treatment under hypnoanesthesia. Conclusions were obtaines as following ; 1) The patients with chronic periodontal disease were surrendered more easily to the operator than those with acute periodontal disease. 2) bleeding was occurred much more than in drug anesthetic state and less in waking state. 3) The different depth of hypnotic state was needed to the different individual. 4) The post-operative pain did not occurred by the operators suggestion. 5. Those operation brought more rapid healing of wounds.

• Genomics & Informatics
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• v.6 no.1
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• pp.1-7
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• 2008

The widespread presence of large-scale genomic variations, termed copy number variation (CNVs), has been recently recognized in phenotypically normal individuals. Judging by the growing number of reports on CNVs, it is now evident that these variants contribute significantly to genetic diversity in the human genome. Like single nucleotide polymorphisms (SNPs), CNVs are expected to serve as potential biomarkers for disease susceptibility or drug responses. However, the technical and practical concerns still remain to be tackled. In this review, we examine the current status of CNV DBs and research, including the ongoing efforts of CNV screening in the human genome. We also discuss the characteristics of platforms that are available at the moment and suggest the potential of CNVs in clinical research and application.

• Journal of Microbiology and Biotechnology
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• v.28 no.10
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• pp.1716-1722
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• 2018

Immunosuppressive drugs are used to make the body less likely to reject transplanted organs or to treat autoimmune diseases. In this study, five immunosuppressive drugs including two glucocorticoids (dexamethasone and prednisolone), one calcineurin inhibitor (cyclosporin A), one non-steroid anti-inflammatory drug (aspirin), and one antimetabolite (methotrexate) were tested for their effects on viral proliferation using feline foamy virus (FFV). The five drugs had different cytotoxic effects on the Crandell-Ress feline kidney (CRFK) cells, the natural host cell of FFV. Dexamethasone-pretreated CRFK cells were susceptible to FFV infection, but pretreatment with prednisolone, cyclosporin A, aspirin, and methotrexate showed obvious inhibitory effects on FFV proliferation, by reducing viral production to 29.8-83.8% of that of an untreated control. These results were supported by western blot, which detected viral Gag structural protein in the infected cell lysate. As our results showed a correlation between immunosuppressive drugs and susceptibility to viral infections, it is proposed that immune-compromised individuals who are using immune-suppressive drugs may be especially vulnerable to viral infection originated from pets.

• Korean Journal of Veterinary Research
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• v.17 no.1
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• pp.5-8
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• 1977

One hundred and fifty seven Escherichia coli strains isolated from 18 cattle (9 dairy cattle received penicillin, streptomycin (SM) or sulfadimethoxine for treatment of diseases and 9 Korean native cattle not received antibiotics) were studied for the drug resistance and distribution of R factors. Of 88 E. coli strains isolated from cattle not received antibiotics, only 1 strain was resistant to SM, but about 46 per cent of 69 E. coli strains isolated from cattle received antibiotics were resistant to SM, tetracycline (TC), ampicillin (AP), kanamycin (KM), chloramphenicol (CM), and sulfisomidine (Su), alone or in combination thereof. Of resistant strains, about 72% were resistant to three or more antibiotics, but 28% were found to singly resistant. The most frequent resistant pattern was triple resistance to AP, KM and Su (37.6%), and quadruple one to SM, TC, CM and Su (12.5%). About 28% of resistant strains carried R factors which were transferable to E. coli ML 1410 $NA^r$ by conjugation.

• The Korean Journal of Physiology and Pharmacology
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• v.28 no.3
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• pp.183-196
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• 2024

Ferroptosis is a novel mechanism of programmed cell death, characterized by intracellular iron overload, intensified lipid peroxidation, and abnormal accumulation of reactive oxygen species, which ultimately resulting in cell membrane impairment and demise. Research has revealed that cancer cells exhibit a greater demand for iron compared to normal cells, indicating a potential susceptibility of cancer cells to ferroptosis. Stomach and colorectal cancers are common gastrointestinal malignancies, and their elevated occurrence and mortality rates render them a global health concern. Despite significant advancements in medical treatments, certain unfavorable consequences and drug resistance persist. Consequently, directing attention towards the phenomenon of ferroptosis in gastric and colorectal cancers holds promise for enhancing therapeutic efficacy. This review aims to elucidate the intricate cellular metabolism associated with ferroptosis, encompassing lipid and amino acid metabolism, as well as iron metabolic processes. Furthermore, the significance of ferroptosis in the context of gastric and colorectal cancer is thoroughly examined and discussed.

• Journal of fish pathology
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• v.19 no.3
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• pp.267-276
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• 2006

Seventy-five streptococci were isolated from diseased olive flounder, Paralichthys olivaceus in Jeju. Their drug susceptibility and transferable multiple drug resistance were characterized. All isolates were resistant to flumequine (AR) and oxolinic acid (OA) and 26 isolates (34.7%) showed 4～6 multiple resistance of ampicillin (ABPC), AR, doxycycline (DOXY), erythromycin (EM), norfloxacin(NOR), OA and oxytetracycline (OTC) in various combinations. pST9 of a transferable R plasmid was detected from a multiple drug resistance strain, Streptococcus sp., ST9 originated from diseased flounder in Jeju, previously. We performed DNA hybridization to know the distribution of plasmid with the same DNA structure as pST9 in streptococci. Thirteen out of 60 isolates analyzed were positive in colony DNA hybridization and the part of bacteria isolated from raw meal was also hybridized with pST9. It suggested that raw meal is one of the origin of the resistance plasmid and R plasmid with DNA structure differing from pST9 is also involving in multiple drug resistance of the streptococci. In conjugation experiment, we found transferable R plasmid carrying OTC, DOXY and/or EM resistance determinant in the 13 resistance strains. all of the streptococci carrying the transferable R plasmid were similar in RAPD patterns. However, pST -type R plasmid was rare in S. iniae most frequently appearing in flounder farm.

• Tuberculosis and Respiratory Diseases
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• v.66 no.3
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• pp.198-204
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• 2009

Background: First-line drugs, if sensitive, are the most potent drugs in the treatment of multidrug-resistant tuberculosis (MDR-TB). This study examined the frequency and risk factors associated with acquired drug resistance to first-line drugs during a standardized treatment using first-line drugs in patients with MDR-TB. Methods: This study included patients who were diagnosed with MDR-TB at the National Masan Tuberculosis Hospital between January 2004 and May 2008, treated with standardized first-line drugs, and for whom the preand post-treatment results of the drug susceptibility test were available. Their medical records were reviewed retrospectively. Results: Of 41 MDR-TB patients, 14 (34.1%) acquired additional resistance to ethambutol (EMB) or pyrazinamide (PZA). Of 11 patients initially resistant to isoniazid (INH) and rifampicin (RFP), 3 (27.3%) acquired additional resistance to both EMB and PZA, and 3 (27.3%) to PZA. Of 18 patients initially resistant to INH, RFP and EMB, 6 (33.3%) acquired additional resistance to PZA. Of 6 patients initially resistant to INH, RFP and PZA, 2 (33.3%) acquired additional resistance to EMB. Ten of the 41 MDR-TB patients (24.4%) changed from resistant to susceptible. No statistically significant risk factors associated with acquired resistance could be found. Conclusion: First-line drugs should be used cautiously in the treatment of MDR-TB in Korea considering the potential acquisition of drug resistance.

• Journal of fish pathology
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• v.9 no.2
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• pp.195-201
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• 1996

Ninety-six isolates of Edwardsiella tarda recovered from outbreaks of Edwardsiellosis in cultured eels(Anguilla japonica) in Kunsan, were examined for drug susceptibility, distribution and transferabilities of R plasmid. All of the E. tarda isolates examined were sensitive to gentamicin(GM), streptomycin(SM), norfloxacin(NF), and amikacin(AK). But most isolates were resistant to sulfadimethoxine(SD, 86 strains), ampicillin(AM, 84 strains), penicillin G(PM, 80 strains), nalidixic acid (NA, 67 strains), oxytetracycline(OT, 44 strains), and oxolinic acid(OA, 37 strains). Twenty different combinations of drug resistance patterns were observed : the frequently encountered pattern was SD-AM-PM-NA-OA(16 strains), SD-AM-PM-NA(14 strains), SD-AM-PM-NA-OT-OA(12 strains), SD-AM-PM-OT(10 strains), and SD-AM-PM-NA-OT(8 strains). Transferable R plasmids were found out to be carried in 78 out of 94 resistant strains, indicating that these isolates carry conjugally transferable R plasmids associated with single or multiple drugs. The frequently observed transferarble R plasmids were AM(8 strains), AM-PM-NA(8 strains), Am-SD(6 strains), PM(6 strains), and SD(6 strains) These results suggest that high dose of various antibacterials might have already been introduced to eel culture system leading to the acquirement of multi-drug resistance to wide range of antibacterials.

• Tuberculosis and Respiratory Diseases
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• v.64 no.2
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• pp.87-94
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• 2008

Background: Surveillance of TB drug resistance (DR) is essential for providing information on the magnitude and trends in resistance, for developing treatment guidelines and for monitoring the effect of interventions. Up to now national surveys of drug resistance of M. tuberculosis have been conducted four times since 1994 among patients registered at health centers. The purpose of this study is to estimate the prevalence of primary drug resistance among new cases identified in private sector, and to compare it with the previous national drug resistance surveys. Methods: The study collected results of drug susceptibility testing (DST) performed at the Korean Institute of Tuberculosis by the request of private sector from January 2003 to December 2005, and then finally selected new cases for the analysis from the database of Korean TB Surveillance (KTBS) by matching patients' name and social identification numbers. Results: Of the 5,132 new patients included in the study, 689 (13.4%) patients were found to have drug resistance at least one drug, 530 patients (10.3%) were isoniazid resistant, 195 patients (3.8%) were multi-drug resistant (MDR), and 21 patients (0.4%) were extensively drug resistant (XDR). The rate of drug resistance tended to decrease annually but it was not statistically significant. When compared with previous national DR surveys in 2003 and in 2004 respectively, they were not significantly different. Conclusion: The prevalence of DR among new cases managed in the private sector did not show significant difference from that of new patients registered in the public sector in the same year.