Immunoenhancing Effects of Euglena gracilis on a Cyclophosphamide-Induced Immunosuppressive Mouse Model

( Hyeonji Yang ),( Kwanyong Choi ),( Kyeong Jin Kim ),( Soo-yeon Park ),( Jin-young Jeon ),( Byung-gon Kim ),( Ji Yeon Kim ) 한국미생물 · 생명공학회 2022 Journal of microbiology and biotechnology Vol.32 No.2

In this study, the effects of the immune stimulator Euglena gracilis (Euglena) in cyclophosphamide (CCP)-induced immunocompromised mice were assessed. The key component β-1,3-glucan (paramylon) constitutes 50% of E. gracilis. Mice were orally administered Euglena powder (250 and 500 mg/kg body weight (B.W.)) or β-glucan powder (250 mg/kg B.W.) for 19 days. In a preliminary immunology experiment, ICR mice were intraperitoneally injected with 80 mg of CCP/kg B.W. during the final 3 consecutive days. In the main experiment, BALB/c mice were treated with CCP for the final 5 days. To evaluate the enhancing effects of Euglena on the immune system, mouse B.W., the spleen index, natural killer (NK) cell activity and mRNA expression in splenocytes lungs and livers were determined. To detect cytokine and receptor expression, splenocytes were treated with 5 μg/ml concanavalin A or 1 μg/ml lipopolysaccharide. The B.W. and spleen index were significantly increased and NK cell activity was slightly enhanced in all the experimental groups compared to the CCP group. In splenocytes, the gene expression levels of tumor necrosis factor-α, interferon-γ, interleukin (IL)-10, IL-6, and IL-12 receptor were increased in the E. gracilis and β-glucan groups compared to the CCP group, but there was no significant difference. Treatment with 500mg of Euglena/ kg B.W. significantly upregulated dectin-1 mRNA expression in the lung and liver compared to the CCP group. These results suggest that Euglena may enhance the immune system by strengthening innate immunity through immunosuppression.

Collection and Preservation of Clinical Isolates from Patients with Nontuberculous Mycobacterial Pulmonary Disease in Nationwide Cohort Study in South Korea

( Hyeonji Kim ),( Jeong Seong Yang ),( Minji Kang ),( Ahn Nam Joung ),( Cha So Jeong ),( Nakwon Kwak ),( Jae-joon Yim ),( Young Ae Kang ),( Jong-seok Kim ),( Hwa-jung Kim ),( Gyeong In Lee ),( Seung H 대한결핵 및 호흡기학회 2021 대한결핵 및 호흡기학회 추계학술대회 초록집 Vol.129 No.-

Background Nontuberculous mycobacterial pulmonary disease (NTM PD) is increasing not only in South Korea but also worldwide. The seriousness of NTM PD is further raised because of the high relapse rate and low cure rate in its treatment. For the optimization of treatments for NTM PD patients, the first multicenter prospective cohort study named ‘NTM-KOREA’ involving eight hospitals and two institutes in South Korea and East Asia was initiated. One of these institutions, the Korean Tuberculosis Research Institute (KIT), plays the role of a strain bank through the Korea Mycobacterium Resource Center (KMRC) collecting and preserving clinical isolates from NTM-KOREA. Methods In South Korea, all NTM drug susceptibility tests have been performed at KIT except one tertiary hospital. When the patient's treatment is initiated, when the negative conversion fails after treatment, or when relapse/reinfection is observed, a drug susceptibility test is requested, and the clinical isolates are then stored in KMRC. Some strains are specifically registered in a mycobacterial extract library consisting of cell wall lipidomes and secreted proteomes. These strains are cultured on solid medium, and by observing the colonies, it is possible to confirm the presence of mixed infection and the rough or smooth colony surface morphology concerning NTM disease progression. Results From October 2018 to the present, a total of 10,510 NTM isolates of NTM-KOREA have been collected, of which 1,387 strains have been registered in the extract library additionally. Conclusion Despite various studies on NTM PD, the existence of biomarkers and bacterial factors applicable to diagnosis and treatment is still not satisfactory. In the future, genetic mutations will be searched through whole genome sequencing (WGS) analysis of treatment-failing/relapse strains, and related SNP will be searched and selected by comparing them with the control group. We will continue to investigate the characteristics of Korean NTM isolates extensively.

Comparison of Minimum Inhibitory Concentration Distributions between Delpazolid and Linezolid Against Mycobacterium Avium, Mycobacterium Intracellulare in Korea

( Hyeonji Kim ),( Jeong Seong Yang ),( Minji Kang ),( Seung Heon Lee ),( Dong Yeon Shin ),( Young Lag Cho ),( Nakwon Kwak ),( Jae-joon Yim ),( Jake Whang ) 대한결핵 및 호흡기학회 2020 대한결핵 및 호흡기학회 추계학술대회 초록집 Vol.128 No.0

Background n South Korea, the major causative agents of nontuberculous mycobacteria (NTM) pulmonary disease (PD) are Mycobacterium avium complex (MAC), composed of M. avium and M. intracellular. Linezolid is a first-line drug for drug-resistant tuberculosis, but it is only used for refractory MAC or M. abscessus lung disease. Since, linezolid has a high minimum inhibitory concentration (MIC) distribution of MAC, with an ECOFF value of 64 ug/ml. Another problem is that linezolid has serious side effects in long-term requiring NTM treatment. Delpazolid, a same oxazolidinone family, showed slightly better MIC distributions for MAC, but the most notable difference is that the side effects are remarkably low. These advantages were sufficiently confirmed through animal experiments and phase 1 clinical trials. However, comparing the antimicrobial activity of linezolid and delpazolid in clinical strains of M. avium, M. intracellulare was not reported yet. Methods The MIC of delpazolid and linezolid were compared with the domestic clinical strains M. avium (n=101) and M. intracellulare (n=104) by broth microdilution Method. Results In the case of M. avium, the separation rate of resistant strains of delpazolid was 45 %, which was 3 % lower than that of linezolid applying the same resistance reference concentration as 16 ug/ml. M. intracellulare was similar with linezolid resistance rate 82.69 % (n = 86) and delpazolid resistance rate 83.65 % (n = 87). Conclusions In this study, we compared the MIC of two antibiotics against clinical isolate. In the M. avium strain, the resistance ratio of linezolid was 3 % higher than that of delpazolid resistance. M. intracellulare resistance rates were similar for linezolid and delpazolid. Since there are significantly fewer side effects, it is expected that delpazolid can replace linezolid in refractory MAC or M. abscessus PD treatment which requiring long-term antibiotic administration.

Establishment and Achievements of Research-oriented Nontuberculous Mycobacterial Resource Center of the Korean Institute of Tuberculosis

( Hyeonji Kim ),( Jeong Seong Yang ),( Minji Kang ),( Seung Heon Lee ),( Nakwon Kwak ),( Jae-joon Yim ),( Young Ae Kang ),( Hong Jo Choi ),( Jong-seok Kim ),( Hwa-jung Kim ),( Jake Whang ) 대한결핵 및 호흡기학회 2020 대한결핵 및 호흡기학회 추계학술대회 초록집 Vol.128 No.0

Background Nontuberculous mycobacteria pulmonary disease (NTM PD) is rapidly increasing worldwide, including in south Korea. As part of the trend to find biomarkers for NTM PD, a multicenter prospective observational cohort study named ‘NTM-KOREA’ involving seven hospitals and two institutes in south Korea was initiated. In order to discover meaningful bacterial factors from preserved strains, the central role of Korean Mycobacterium Resource Center (KMRC) in KIT has been extended from strain preservation to research since 2018. Methods In South Korea, all NTM drug susceptibility tests have been performed at KIT except one tertiary hospital. When the patient's treatment is initiated, when the negative conversion fails after treatment, or when relapse/reinfection is observed, a drug susceptibility test is requested, and the clinical isolates are then stored in KMRC. Some strains are specifically registered in a mycobacterial extract library consisting of cell wall lipidomes and secreted proteomes. These strains are cultured on solid medium, and by observing the colonies, it is possible to confirm the presence of mixed infection and the rough or smooth colony surface morphology concerning NTM disease progression. Results From October 2018 to the present, a total of 7,000 NTM isolates of NTM-KOREA have been collected, of which 350 strains have been registered in the extract library additionally. Through a recent joint study with Seoul National University Hospital, we found that the treatment rate of clofazimine as an NTM treatment is related to minimum inhibitory concentration of each clinical isolate. Conclusions Despite various studies on NTM PD, the existence of biomarkers and bacterial factors applicable to diagnosis and treatment is still not satisfactory. When considering as an infectious disease, the causative agent is also very important as well as biomarkers. Accordingly, we will continue to investigate the characteristics of Korean NTM isolates extensively and to select prominent bacterial factors.

Development of an MMP-2 Activity Assay Method Using a Pro-caspase-3 Sensor

Dokyung YANG,HyeonJi PARK,TaeHyeon YOO 한국생물공학회 2016 한국생물공학회 학술대회 Vol.2016 No.4

Fluvoxamine Treatment of Patients with Symptomatic COVID-19 in a Community Treatment Center: A Preliminary Result of Randomized Controlled Trial

Seo Hyeonji,Kim Haein,Bae Seongman,Park Seonghee,Chung Hyemin,Sung Heungsup,Jung Jiwon,Kim Min-Jae,Kim Sung-Han,Lee Sang-Oh,Choi Sang-Ho,Kim Yang Soo,Son Ki Young,Chong Yong Pil 대한감염학회 2022 Infection and Chemotherapy Vol.54 No.1

Background This study aimed to evaluate whether fluvoxamine reduces clinical deterioration in adult patients with mild to moderate coronavirus disease 2019 (COVID-19), and to identify risk factors for clinical deterioration in patients admitted to a community treatment center (CTC). Materials and Methods A randomized, placebo-controlled trial was conducted in a CTC, in Seoul, Korea from January 15, 2021, to February 19, 2021. Symptomatic adult patients with positive results of severe acute respiratory syndrome coronavirus 2 real time-polymerase chain reaction within 3 days of randomization were assigned at random to receive 100 mg of fluvoxamine or placebo twice daily for 10 days. The primary outcome was clinical deterioration defined by any of the following criteria: oxygen requirement to keep oxygen saturation over 94.0%, aggravation of pneumonia with dyspnea, or World Health Organization clinical progression scale 4 or greater. Results Of 52 randomized participants [median (interquartile range) age, 53.5 (43.3 - 60.0) years; 31 (60.0%) men], 44 (85.0%) completed the trial. Clinical deterioration occurred in 2 of 26 patients in each group (P >0.99). There were no serious adverse events in either group. Clinical deterioration occurred in 15 (6.0%) of 271 patients admitted to the CTC, and all of them were transferred to a hospital. In multivariate analysis, age between 55 and 64, fever and pneumonia at admission were independent risk factors for clinical deterioration. Conclusion In this study of adult patients with symptomatic COVID-19 who were admitted to the CTC, there was no significant differences in clinical deterioration between patients treated with fluvoxamine and placebo (ClinicalTrials.gov Identifier: NCT04711863). Background This study aimed to evaluate whether fluvoxamine reduces clinical deterioration in adult patients with mild to moderate coronavirus disease 2019 (COVID-19), and to identify risk factors for clinical deterioration in patients admitted to a community treatment center (CTC). Materials and Methods A randomized, placebo-controlled trial was conducted in a CTC, in Seoul, Korea from January 15, 2021, to February 19, 2021. Symptomatic adult patients with positive results of severe acute respiratory syndrome coronavirus 2 real time-polymerase chain reaction within 3 days of randomization were assigned at random to receive 100 mg of fluvoxamine or placebo twice daily for 10 days. The primary outcome was clinical deterioration defined by any of the following criteria: oxygen requirement to keep oxygen saturation over 94.0%, aggravation of pneumonia with dyspnea, or World Health Organization clinical progression scale 4 or greater. Results Of 52 randomized participants [median (interquartile range) age, 53.5 (43.3 - 60.0) years; 31 (60.0%) men], 44 (85.0%) completed the trial. Clinical deterioration occurred in 2 of 26 patients in each group (P >0.99). There were no serious adverse events in either group. Clinical deterioration occurred in 15 (6.0%) of 271 patients admitted to the CTC, and all of them were transferred to a hospital. In multivariate analysis, age between 55 and 64, fever and pneumonia at admission were independent risk factors for clinical deterioration. Conclusion In this study of adult patients with symptomatic COVID-19 who were admitted to the CTC, there was no significant differences in clinical deterioration between patients treated with fluvoxamine and placebo (ClinicalTrials.gov Identifier: NCT04711863).

전남지역 농업용 지하수의 수질특성

김현지(Hyeonji Kim),김선국(Sunkook Kim),신길호(Gilho Shin),김성우(Sungwoo Kim),양승구(Seonggu Yang),김희권(Heekwon Kim),허승오(Seungoh Hur) 한국토양비료학회 2017 한국토양비료학회 학술발표회 초록집 Vol.2017 No.10

Risk Factors for Mortality in Patients with Klebsiella pneumoniae Carbapenemase-producing K. pneumoniae and Escherichia coli bacteremia

Seo Hyeonji,Bae Seongman,Kim Min-Jae,Chong Yong Pil,Kim Sung-Han,Lee Sang-Oh,Choi Sang-Ho,Kim Yang Soo,Jung Jiwon 대한감염학회 2021 Infection and Chemotherapy Vol.53 No.3

Background: Klebsiella pneumoniae carbapenemase (KPC)-producing Enterobacterales bacteremia is associated with significant mortality; however, no optimal antibiotic strategy is available. We aimed to evaluate the clinical outcomes according to the antibiotic regimens and identify risk factors for mortality in patients with KPC-producing K. pneumoniae and Escherichia coli bacteremia. Materials and Methods: This retrospective cohort study included all adult patients with monomicrobial bacteremia (KPC-producing K. pneumoniae or E. coli) between January 2011 and March 2021 at a 2,700-bed tertiary center. Results: Ninety-two patients were identified; 7 with E. coli bacteremia, and 85 with K. pneumoniae bacteremia. Thirty-day mortality was 38.0% (35/92). Non-survivors were more likely to have had nosocomial infection (88.6% vs. 63.2%, P = 0.01), high APACHE II scores (mean [interquartile range], 22.0 [14.0 - 28.0] vs. 14.0 [11.0 - 20.5], P <0.001), and septic shock (51.4% vs. 26.3%, P <0.001) and less likely to have been admitted to the surgical ward (5.7% vs. 22.8%, P = 0.04), undergone removal of eradicable foci (61.5% vs. 90.6%, P = 0.03), and received appropriate combination treatment (57.1% vs. 78.9%, P = 0.03) than survivors. No significant difference in mortality was observed according to combination regimens including colistin, aminoglycoside, and tigecycline. In multivariable analysis, high APACHE II scores (adjusted odds ratio [aOR], 1.14; 95% confidence interval [CI], 1.06 - 1.23, P <0.001), and appropriate definitive treatment (aOR, 0.25; CI, 0.08 - 0.74, P = 0.01) were independent risk factors for mortality. Conclusion: High APACHE II scores and not receiving appropriate definitive treatment were associated with 30-day mortality. Mortality did not significantly differ according to combination regimens with conventional drugs such as aminoglycoside and colistin.

Distributions of Minimum Inhibitory Concentration for Delpazolid and Linezolid in Drug-resistant Mycobacterium Tuberculosis in South Korea

( Jeong Seong Yang ),( Hyeonji Kim ),( Minji Kang ),( Seung Heon Lee ),( Dong Yeon Shin ),( Young Lag Cho ),( Nakwon Kwak ),( Jae-joon Yim ),( Jake Whang ) 대한결핵 및 호흡기학회 2020 대한결핵 및 호흡기학회 추계학술대회 초록집 Vol.128 No.0

Background As a recommendation for the treatment of multidrug-resistant (MDR) / rifampicin-resistant tuberculosis (RR) in WHO guidelines, the use of linezolid is strongly recommended for longer MDR-TB regimens. However, there are many reports of side effects from using linezolid. Delpazolid is a new antibiotic of an Oxazolidinone family, same as linezolid. Delpazolid was reported to be safer compared to linezolid with lower adverse effects. In this study, minimum Inhibitory Concentration (MIC) of drug-resistant TB isolates was measured for linezolid and delpazolid, and the distribution was confirmed. Methods A total of 514 resistant-TB clinical isolates were randomly selected from the Korea Mycobacterium Resource Center at the Korean institute of tuberculosis; respectively, 1 isoniazid-resistant, 389 MDR, 100 RR, and 24 extensively-resistant TB. The MIC test of linezolid and delpazolid was performed using Middlebrook 7H9 broth with 10% oleic-albumin-dextrose-catalase and 2,3 diphenyl-5-(2-thienyl)-tetrazolium chloride by broth microdilution Method in 96-well microplate. Results The MIC90 of linezolid and delpazolid were 0.5 mg/L and 1 mg/L, respectively. Additionally, for the MIC distribution, tentative epidemiological cutoff (ECOFF) of linezolid and delpazolid were determined as 1 mg/L and 4 mg/L. According to the ECOFFs, the number of resistant strains was 16 (3.11 %) and 10 (1.95 %) isolates for linezolid and delpazolid. Furthermore, 9 isolates were confirmed to be resistant to both antibiotics. Conclusions In this study, we compared the MIC distributions of linezolid and delpazolid in drug resistant-TB isolates, and confirmed the MIC90 and ECOFF values, and we also identified resistant isolates of linezolid and delpazolid, respectively. In further studies, the detailed resistance mechanism will be investigated in 8 isolates which have different resistance to the same oxazolidinone antibiotics. Finally, it will be confirmed whether there is a new mechanism of resistance that is still unknown for 9 strains having common resistance.

Subspecies-level Mixed Infection Confirmed by Colony Phenotype of Nontuberculous Mycobacteria Clinical Isolates in South Korea

( Jeong Seong Yang ),( Hyeonji Kim ),( Minji Kang ),( Nakwon Kwak ),( Jae-joon Yim ),( Young Ae Kang ),( Jong-seok Kim ),( Hwa-jung Kim ),( Gyeong In Lee ),( Seung Heon Lee ),( Jake Whang ) 대한결핵 및 호흡기학회 2021 대한결핵 및 호흡기학회 추계학술대회 초록집 Vol.129 No.-

Background Non-tuberculous mycobacteria (NTM) are ubiquitous pathogens in opportunistic infection. Because the types of NTM existing in the living environment are diverse, it is expected that NTM patients will be exposed to new types of NTM bacteria every day. Therefore, cases of mixed infection in non-tuberculous mycobacterium lung disease are very common, and it has already been known that the statistical significance between mixed infection and low treatment success rate. In this study, we confirmed the possibility of the mixed infection among heterogeneous or subspecies-level through various phenotypes in NTM clinical isolates. Methods Total 1,095 clinical isolates of NTM collected by Korea Mycobacterium Resource Center from March 2020 to June 2021 were used. Identification of the species was performed through Mycobacteria Genoblot Assay by extracting DNA of cultured strains. Confirmation of the morphological diversity was observed by cultured colony shapes inoculating strains through three-phase streaking pattern on 7H10 agar medium. Results A total of 1095 clinical strains were identified, and that Results were as follows: 397 M. avium, 397 M. intracellulare, 121 M. abscessus, 62 M. massiliense, 20 M. fortuitum, 43 rare species, and 55 Mixed species. Excluding mixed species, 122 M. avium, 262 M. intracellulare, 9 M. abscessus, 2 M. massiliense, 7 M. fortuitum and 3 rare species had multiple phenotypic colonies in one clinical isolate, respectively. Conclusion Mixed infection through molecular diagnosis was confirmed in 55 out of 1095, but cases of 405 had phenotypic diversity among clinical isolates confirmed as a single species. It suggests that additional mixed infections not confirmed by molecular diagnosis is may exist at the species-level or subspecies-level, or that a phenotypic transition may occur. In order to observe the correct treatment response and the prognosis for NTM disease patients, it is necessary to confirm such a mixed infection or phenotypic transition.