• Tuberculosis and Respiratory Diseases
• /
• v.55 no.1
• /
• pp.41-58
• /
• 2003

Background : The resurgence of tuberculosis and the widespread emergence of multidrug-resistant M. tuberculosis have emphasized the importance of rapid and accurate diagnostic procedures. Recently, the oligonucleotide chip has proven to be a useful tool in the rapid diagnosis of infectious diseases. The purpose of this study was to rapidly and accurately detect specific mutations in the rpoB, katG and rpsL genes associated with rifampin, isoniazid and streptomycin resistance in M. tuberculosis, respectively, using a single oligonucleotide chip. Method : For detection of drug-resistance, 7 wild-type and 13 mutant-type probes for rifampin, 2 wild-type and 3 mutant-type probes for isoniazid, and 2 wild-type and 2 mutant-type probes for streptomycin were designed and spotted onto glass slides. Fifty-five cultured samples of M. tuberculosis were amplified by PCR, and then underwent hybridization and scanning. Direct sequencing was done to verify the results from the oligonucleotide chip and to analyze the types of mutations. Result : Thirty-five cases out of 40 rifampin-resistant strains(~88%) had mutations in the rpoB gene. One case had a new mutation(D516F, GAC R TTC) and another known mutation together. Twenty cases out of 42 isoniazid-resistant strains(~50%) had mutations in the katG gene, while 7 cases out of 9 streptomycin-resistant strains(~78%) had mutations in the rpsL gene. From these results, the oligonucleotide chip was confirmed to be able to detect the most frequent mutations from the genes associated with rifampin, isoniazid and streptomycin resistance. The results proved that the drug-resistance detection probes were specific. When the results from the oligonucleotide chip and DNA sequencing were compared, the types of mutations were exactly matched. Conclusion : The diagnostic oligonucleotide chip with mutation specific probes for drug resistance is a very reliable and useful tool for the rapid and accurate diagnosis of drug resistance against rifampin, isoniazid and streptomycin in M. tuberculosis infections.

• Korean Journal of Weed Science
• /
• v.12 no.2
• /
• pp.132-143
• /
• 1992

The study was conducted to find out synergistic effects by interaction on the basis on anatomical changes between paddy rice and weed species by mixture use of oxyfluorfen and bensulfuron at 0, $10^{-6}$ and $10^{-4}$M, respectively. Tissues were sampled at 72 hrs after soaking treatment and prepared for light microscopic examination and sectioned longitudinally and transversely stem into $8{\mu}m$ thick. As the results of microscopic examination, the major response of treated plant involved rupture and constrict in mesophyll cells and epidermal cells, and shrinks in bundle sheath cells by oxyfluorfen and disorganization and swelling in meristems by bensulfuron. Anatomical changes in rice was the least affected by even high concentration and two herbicide mixtures, whereas Echinochloa crus-galli was severely disorganized in meristem regions and ruptured in epidermal cells by mixture use. Monochoria vaginalis was completely ruptured by any treatment concentrations and mixtures. Scirpus juncoides was considerably tolerant to both herbicides and their mixture and was similar to those that occur in rice. Perennial weed, Sagittaria pigmaea was observed vacuolation, non-nucleation of cell, and irregular cell layering but in mixture injury was slight. Cyperus serotinus was severely shrunk and ruptured by mixture treatment. Eventually anatomical variations in all weed species was shown synergistic effect by use of herbicide mixtures.

• Journal of The Korean Ophthalmological Society
• /
• v.60 no.2
• /
• pp.144-151
• /
• 2019

Purpose: Intravitreal aflibercept, ranibizumab, bevacizumab, and dexamethasone are the most widely used drugs in the treatment of diabetic macular edema (DME). The aim of this study was to compare the efficacy and safety of anti-vascular endothelial growth factors and dexamethasone for the treatment of DME. Methods: There were nine previous systematic reviews on this topic; we updated these high-quality reviews. Seven studies were added to two studies following a literature search. Efficacy outcomes were 1) average improvement in visual acuity, 2) proportion of patients who experienced an improvement in vision (an increase in best-corrected visual acuity (BCVA) of ${\geq}15$ in the Early Treatment Diabetic Retinopathy Study [ETDRS]), and 3) proportion of patients who experienced worsening vision (a decrease in BCVA of ${\geq}15$ in the ETDRS). Safety outcomes included systemic adverse events and ocular-related adverse events. Results: The mean difference in the BCVA for ranibizumab versus bevacizumab treatment was 0.16 (95% confidence interval [CI]: -0.02, 0.34), and that for ranibizumab versus aflibercept was -0.08 (95% CI: -0.26, 0.10). The mean difference in the change of BCVA for aflibercept versus ranibizumab was -0.20 (95% CI: -0.40, -0.01), and that for aflibercept versus bevacizumab was -0.34 (95% CI: -0.53, -0.14). Other efficacy outcomes showed similar trends, and there was no significant difference between treatments. There was also no significant difference in both systemic and ocular adverse events rates between the treatments. Conclusions: In DME patients, the efficacy of aflibercept was found to be higher with respect to BCVA changes compared with ranibizumab or bevacizumab. However, there were no significant difference in terms of visual acuity improvement or visual acuity of more than 15 letters, nor in terms of anti-vascular endothelial growth factors (as a safety outcome).

• Tuberculosis and Respiratory Diseases
• /
• v.48 no.2
• /
• pp.191-202
• /
• 2000

Background: Bronchial asthma is characterized by airway hyperresponsiveness(BHR) and inflammation. The cyclooxygenase(COX) is believed to be one of the important enzymes in these inflammatory reactions. Recently, the COX was divided into two isoforms, COX1 and COX2. COX2 is induced by lipopolysaccharide and some cytokines at the inflammation site. Prostaglandin E2(PGE2), produced from COX2, may affect airway inflammation. The purpose of this study is to evaluate the effect of COX2 inhibitor on COX2 expression, plasma PGE2, airway resistance and histologic finding in an animal asthma model. Methods : Sprague-Dawley rats were divided into 3 groups. The normal control group did not receive any treatment, but the asthma control group was sensitized by ovalbumin but not treated with the COX2 inhibitor(nimesulide, Mesulid$^{(R)}$). The treatment group was sensitized and treated with nimesulide. Specific airway resistance(sRaw) before and after nimesulide ingestion was investigated. The PGE2 level in the plasma was examined and COX2 immunogold-silver stain on lung tissue was performed. Results: sRaw and eosionophilic infiltration on airway, which increased in the asthma control group, was compared to normal control(p=0.014). However, there was no difference in eosinophilic infiltration between asthma control and treatment groups(p=0.408) and no difference in COX2 expression on bronchiolar epithelium among the three groups. Plasma PGE2 levels were not statically different among the three groups. Conclusion: The role of COX2 in the allergen-induced BHR was not significant The effect of nimesulide was not observed on BHR, COX2 expression, and plasma PGE2 level. Therefore, COX2 may not be a major substance of allergic asthma.

• Tuberculosis and Respiratory Diseases
• /
• v.51 no.4
• /
• pp.334-345
• /
• 2001

Background : Pulmonary tuberculosis(TB) is still prevalent and remains a significant clinical problem for the elderly. However, the disease presents in many ways, and there are frequent adverse drug reactions that may prevent the early diagnosis and treatment of elderly TB patients compared to the young. The purpose of this study was to determine whether or not there are any differences in the clinical feature of pulmonary tuberculosis(TB) in both the diagnosis and treatment between the young (less than 64 years) and the elderly (65 years and more). Methods : The medical records of 125 young and 70 elderly pulmonary TB patients, who were diagnosed with and treated for pulmonary TB at the Seoul Municipal Boramae Hospital from November 1991 to January 1997, were analyzed retrospectively. Results : Anorexia(12% vs. 31.4%), general weakness (20.0% vs. 54.3%), dyspnea(21.6% vs. 37.1%) and an abnormal mentality (0.8% vs. 15.7%) were more frequent presenting symptoms in elderly TB patients, whereas hemoptysis (32.8% vs. 10.0%) and fever (BT > $37^{\circ}C$, 58.4% vs. 35.7%) were more frequent in the young. The elderly had a higher number of cardiovascular and chronic obstructive pulmonary diseases as underlying illnesses. In chest PA, there were no differences in the location of the TB lesion, but the appearances were initially diagnosed more frequently as pneumonia or lung cancer (8.8% vs. 30.0%, p<0.05) in the elderly. There was no difference in the detection rate of acid fast bacilli(AFB) in the sputum between the two groups. There were no differences in the treatment response and follow-up loss. However, adverse drug reactions (13.6% vs. 45.7%, p<0.05), and changes in medication (4.9% vs. 25.7%, p<0.05) during treatment occurred more frequently in the elderly. One among the 125 young patients died from tuberculosis whereas 6 among the 70 elderly patients died from the disease. Conclusion : Because the clinical and radiological presentations were more atypical, a sputum AFB smear and culture should be done immediately in the elderly who are TB. The elderly experienced more frequent adverse drug reactions and mortality during treatment, but the response to treatment was good and rapid.

• Tuberculosis and Respiratory Diseases
• /
• v.57 no.3
• /
• pp.226-233
• /
• 2004

Background : Interferon-gamma (IFN-${\gamma}$) is a critical cytokine in the defense against a Mycobacterium tuberculosis infection. Even though IFN-${\gamma}$ has occasionally been used in the treatment of refractory multidrug-resistant tuberculosis (MDR-TB) with some promising results, there is still some controversy regarding the therapeutic efficacy of IFN-${\gamma}$. This study was performed to examine the effect of subcutaneous IFN-${\gamma}$ in the treatment of MDR-TB patients. Methods : Six patients with refractory MDR-TB were enrolled in this study. Two million IU of IFN-${\gamma}$ was administered subcutaneously three times a week with the concomitant administration of antituberculous drugs for at least for 28 weeks. During the IFN-${\gamma}$ therapy, the sputum smear and culture, radiological and clinical evaluations were performed every 4 weeks throughout the study period. Results : The mean age of the 6 patients was 37 years (ranges, 15-61 years). The drug susceptibility test to standard antituberculous drugs revealed resistance to an average of 6.8 (${\pm}1.2$) agents including isoniazid and rifampicin. An average of 10.8 (${\pm}1.3$) antituberculous drugs were prescribed before IFN-${\gamma}$ therapy. The culture became negative in 2 patients (33%) after initiating IFN-${\gamma}$ therapy; one at 8 weeks, and the other at 24 weeks. Finally, after stopping the IFN-${\gamma}$ therapy after 28 weeks, the culture became positive again in the two patients who were culture-negative. The other 4 patients who failed in the culture conversion are still on antituberculous treatment except for one who died of tuberculosis. Conclusion : Even though 28 weeks of subcutaneous IFN-${\gamma}$ therapy in combination with antituberculous drugs was successful in inducing the culture-negative conversion in some patients with refractory MDR-TB, the culture became positive again after stopping the IFN-${\gamma}$ therapy. This suggests that subcutaneous IFN-${\gamma}$ therapy may have suppressive effect on tuberculosis only during the IFN-${\gamma}$ therapy period in some patients. Further studies will be needed to determine the optimum dose, the administration route, the duration of therapy, and the predicting factors of the response to adjuvant IFN-${\gamma}$ therapy.

• Korean Journal of Weed Science
• /
• v.14 no.4
• /
• pp.233-238
• /
• 1994

The experiment on sprouting and emergence properties of Eleocharis kuroguwai was conducted at laboratory and greenhouse conditions in 1993. Most of tubers had the apical dominance of buds at sprouting and had the competitive relationship for mesocotyl elongation. When pyrazosulfuron was applied on soil surface, all of apical buds were killed, but the first and second lateral buds survived to 50% and 90%, respectively, and the third lateral buds were almost at presprouted state. The tubers at 10-15cm deep soil emerged 1 week late and 35% low in emergence rate compared with the tubers at 2-5cm deep. As the plants emerged from the deep soil, the mesocotyl and the roots were distributed at deep soil more or less. Among the tubers buried at 10cm and 15cm deep soil, 25% and 30% respectively were not emergerd due to the suspension of mesocotyl elongation. Although the roots and shoots were removed from the tubers at the stage of 20cm high, all of mother tubers emerged again even 2 weeks late.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.41 no.3
• /
• pp.348-353
• /
• 1996

Mutation tachniques inducing more useful mutations and reducing somatic effects need to be improved for crop breeding. Seeds of barley varieties ; Dema, Grosso were treated with two types of mutagens ; 1) chemical treatment: single treatment or double treatment of two mutagens (N-nitroso-N-methylurea ; MNH, Sodium Azide; NaN$_3$) 2) gamma ray irradiation treatment. After treatment, half of seeds were used for germination test and half of seeds were sown to the field. With the higher dose of mutagen both chemical and gamma ray were plants treated, the higher rate of growth reduction rate was in M$_1$ seedling. In chemical treatment, germination rate of seeds, growth rate of coleoptile and root in double treatment of chemical mutagens were better than single treatments, especially in same dose. Growth inhibition rate of plant in double treatment of 1.0mM MNH(0.5mM MNH + 0.5mM MNH), for example, were less than one of plants of single treatment of 1.0mM MNH in pot and petri dish test. Growth reduction rate of culm and fertility rate in M$_1$ plants double treated in same dose of single treatment were also less than single one. With the higher dose of mutagen both chemical and gamma ray were plants treated, the higher frequency of chlorophyll mutants was in M$_2$ seedling. The rate of chlorophyll mutants in double treatment of chemical mutagens were higher than single treatment. Double treatment methods can be a improved method for induction of new good mutants, which were induced more useful mutations and reduced harmful somatic effects.

• Journal of Applied Biological Chemistry
• /
• v.63 no.3
• /
• pp.267-274
• /
• 2020

The dissipation characteristics and kinetics of fungicide mandipropamid and insecticide thiamethoxam in lettuce under greenhouse conditions were investigated at three different lettuce-growing fields for estimating the pre-harvest residue limits (PHRLs). The analytical methods were fully validated for the quantitation of pesticide residues using High-Performance Liquid Chromatography-Photo Diode Array detector or Ultraviolet-Visible Detector and applied to real samples. The lettuces suitable for shipment were harvested during 10 days including pre-harvest interval after treatment at the recommended dose by safe-use guidelines. The initial mean residues in different fields were 6.68-17.87 and 4.96-8.31 mg/kg for mandipropamid and thiamethoxam, respectively, which decreased to 16-54 and 14-44% in 10 days. The clothianidin, a metabolite of thiamethoxam, was detected in <0.02 to 0.37 mg/kg. The dissipation of both pesticides followed first-order kinetics over a period of 10 days after application. Based on the residue data, the mean dissipation rate constant (λ) and biological half-lives (T_1/2) were estimated to be -0.1060 and 6.5 days of mandipropamid and -0.1236 and 5.6 days of thiamethoxam. The PHRLs for lettuce on the 10th and 5th day before harvesting were calculated to be 63.24 and 43.56 mg/kg for mandipropamid, and 44.66 and 25.88 mg/kg for thiamethoxam, with -0.0746 and -0.1091 of the upper 95% confidence intervals of dissipation rate constant, respectively. This work would be useful as guidance for adjusting the shipment date and contribute to stabilizing the income of farmers in Korea.

• Journal of Life Science
• /
• v.22 no.9
• /
• pp.1268-1276
• /
• 2012

The emergence and dissemination of carbapenem-resistant bacteria have resulted in limitations of antibiotic treatment and potential outbreaks of metallo-${\beta}$-lactamase (MBL) producing Pseudomonas aeruginosa resistant to carbapenems. In this study, we conducted molecular characterization of the MBL genes of the ${\beta}$-lactam drug-resistant P. aeruginosa and prepared basic data for treatment and prevention of proliferation of antimicrobial-resistant bacterial infections. Forty-two P. aeruginosa isolates of 254 were resistant to imipenem or meropenem. Among the 42 isolates, 28 isolates were positive for the Hodge test, and 23 isolates were positive for the EDTA-disk synergy test (EDST). MBLs were detected in 59.5% (25/42) of P. aeruginosa isolates. Eight isolates harbored $bla_{IMP-6}$, whereas 17 isolates harbored $bla_{VIM-2}$. The $bla_{IMP-6}$ gene was in a class 1 integron containing five gene cassettes: $bla_{IMP-6}$, qac, aacA4, $bla_{OXA-1}$, and aadA1. Some strains that produce IMP-6 and VIM-2 showed epidemiological relationships. The $bla_{IMP-6}$ gene in carbapenem-resistant P. aeruginosa showed an identical pattern to a gene cassette that was reported at a hospital in Daegu, Korea. Therefore, MBL-producing P. aeruginosa is already endemic in the community. We are concerned that the existence of carbapenem-resistant bacteria containing the blaMBL gene may increase pressure on antibiotic selection when treating infections. We believe that we should select appropriate antibiotics based on the antibiotic susceptibility test and continue the research to prohibit the emergence and spread of antibiotics resistant bacteria.