• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제32권5호
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• pp.436-446
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• 2006

The purpose of this study was to isolate and identify the bacteria in chronic maxillary sinusitis (CMS) lesions from 3 patients and to determine the antimicrobial susceptibility of them against 10 antibiotics. One of them was odontogenic origin and the others were non-odontogenic origin. Pus samples were collected by needle aspiration from the lesions and examined by culture method. Bacterial culture was performed in three culture systems (anaerobic, CO2, and aerobic incubator). Identification of the bacteria was performed by 16S rRNA gene (16S rDNA) nucleotide sequencing method. To test the sensitivity of the bacteria isolated from the maxillary sinusitis lesions against seven antibiotics, penicillin G, amoxicillin, tetracycline, ciprofloxacin, cefuroxime, erythromycin, clindamycin, and vancomycin, minimum inhibitory concentration (MIC) was performed using broth dilution assay. Our data showed that enterobacteria such as Enterobacter aerogenes (30%), Klebsiella pneumoniae (25%), and Serratia marcescens (15%) were predominately isolated from the lesion of non-odontogenic CMS of senile patient (70 year old). Streptococcus spp. (40.3%), Actinomyces spp. (27.4%), P. nigrescens, M. micros, and P. anaerobius strains were isolated in the lesion of odontogenic CMS. In the lesion of non-odontogenic CMS, Streptococcus spp. (68.4%), Rothia spp. (13.2%), and Actinomyces sp. (10.5%) were isolated. The susceptibility pattern of 10 antibiotics was determined according to the host of the bacteria strains ratter than the kinds of bacterial species. Even though the number of CMS was limited as three, these results indicate that antibiotic susceptibility test must be accompanied with treatment of CMS. The combined treatment of two or more antibiotics is better than single antibiotic treatment in the presence of multidrug-resistant bacteria in the CMS lesions.

• Asian Pacific Journal of Cancer Prevention
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• 제15권10호
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• pp.4353-4358
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• 2014

Background: PI3/AKT and NF-kB signaling pathways are constitutively active in acute myeloid leukemia and cross-talk between the two has been shown in various cancers. However, their role in acute myeloid leukemia has not been completely explored. We therefore used cell penetrating inhibitor peptides to define the contributions of AKT and NF-kB to survival and multi drug resistance (MDR) in HL-60 cells. Materials and Methods: Inhibition of AKT and NF-kB activity by AKT inhibitor peptide and NBD inhibitor peptide, respectively, resulted in decreased expression of mRNA for the MDR1 gene as assessed by real time PCR. In addition, treatment of HL-60 cells with AKT and NBD inhibitor peptides led to inhibition of cell viability and induction of apoptosis in a dose dependent manner as detected by flow cytometer. Results: Finally, co-treatment of HL-60 cells with sub-optimal doses of AKT and NBD inhibitor peptides led to synergistic apoptotic responses in AML cells. Conclusions: These data support a strong biological link between NF-kB and PI3-kinase/AKT pathways in the modulation of antiapoptotic and multi drug resistant effects in AML cells. Synergistic targeting of these pathways using NF-kB and PI3-kinase/AK inhibitor peptides may have a therapeutic potential for AML and possibly other malignancies with constitutive activation of these pathways.

• 한국임상약학회지
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• 제27권2호
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• pp.92-98
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• 2017

Background: Nebulized colistimethate is increasingly used, because there are problems such as renal dysfunction and low distribution within the lungs when colistimethate is administered intravenously. This study was designed to compare and analyze the changes in renal function by of nebulized colistimethate treatment for its safe administration. Methods: This study retrospectively reviewed the electronic medical records of adult patients above 19 years old, receiving only the nebulized colistimethate at least 4 days in Yonsei university health system from Nov 2014 to Aug 2015. Acute kidney injury (AKI) was determined by using the RIFLE criteria (Risk, Injury, Failure, Loss and End-stage renal disease) according to serum creatinine (SCr) levels before and after use of nebulized colistimethate. Results: 48 patients were included our study and their SCr increased significantly after nebulized colistimethate treatment ($SCr_0$ vs. $SCr_1$; $0.85{\pm}0.80$ vs. $1.00{\pm}0.82mg/dL$, n=48, p<0.001), but the changes were in normal range according to the standards at Yonsei university health $system^a$. Among 48 patients, 38 patients were in the non-AKI group (79.2%), and 10 patients developed AKI (20.8%). Within the AKI group, 2 patients were in the Injury group (20%) and the other 8 in the Risk group (80%). Conclusion: There was no significant difference in age, dosage and duration of treatment between AKI group and non-AKI group (p>0.05). The study has a significance in that it reviewed the safety of nebulized colistimethate only treatment to national patients, analyzing its nephrotoxicity. It has confirmed that nebulized colistimethate is a safer method than intravenous injection, and requires to establish a guideline for the use of nebulized colistimethate in further studies with broader patient groups. $^a$ : SCr Male 0.68-1.19 mg/dL, Female 0.49-0.91 mg/dL.

• 환경생물
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• 제25권4호
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• pp.342-348
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• 2007

새로운 항균물질의 탐색이 활발하다. 선행연구에서 새로운 항균활성물질을 생산하는 세균이 한국토양에서 분리되어 Paenibacillus polymyxa DY1으로 동정 및 명명되었으며, 다제내성 장내세균들에 대한 항균활성 특성이 규명되어 새로운 항생물질로서 잠재력을 보여주었다. 본 연구에서 배지의 탄소원, 무기질소원, 유기질소원, 아미노산, 무기염류 등의 영양 조성물과 물리화학적 생장조건이 P. polymyxa DY1 균체의 생장과 항균활성 생산에 미치는 영향을 조사하였다. 균체의 생장을 위하여 기초배지에 0.6% dextrose, 1.4% ammonium phosphate monobasic, 0.9% peptone, 2.4% glutamine, 2 mM sodium molibdate를 가한 후 pH를 8.0으로 조정하고 $35^{\circ}C$에서 30$\sim$48시간동안 180 rpm으로 진탕배양하는 것이 가장 적합하였다. P. polymyxa DY1 항균활성의 생산은 기초배지에 1% dextrose, 1.5% ammonium sulfate, 1.1% casamino acid, 1.9% aspartic acid, 2 mM ferrous sulfate를 가한 배지를 pH 8.0으로 조정하고 $35^{\circ}C$에서 30$\sim$48시간동안 180 rpm으로 진탕배양하는 조건에서 가장 높았다.

• Journal of Chest Surgery
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• 제45권2호
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• pp.110-115
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• 2012

Background: Pneumonectomy remains the ultimate curative treatment modality for destroyed lung caused by tuberculosis despite multiple risks involved in the procedure. We retrospectively evaluated patients who underwent pneumonectomy for treatment of sequelae of pulmonary tuberculosis to determine the risk factors of early and long-term outcomes. Materials and Methods: Between January 1980 and December 2008, pneumonectomy or pleuropneumonectomy was performed in 73 consecutive patients with destroyed lung caused by tuberculosis. There were 48 patients with empyema (12 with bronchopleural fistula [BPF]), 11 with aspergilloma and 7 with multidrug resistant tuberculosis. Results: There were 5 operative mortalities (6.8%). One patient had intraoperative uncontrolled arrhythmia, one had a postoperative cardiac arrest, and three had postoperative respiratory failure. A total of 29 patients (39.7%) suffered from postoperative complications. Twelve patients (16.7%) were found to have postpneumonectomy empyema (PPE), 4 patients had wound infections (5.6%), and 7 patients required re-exploration due to postoperative bleeding (9.7%). The prevalence of PPE increased in patients with preoperative empyema (p=0.019). There were five patients with postoperative BPF, four of which occurred in right-side operation. The only risk factor for BPF was the right-side operation (p=0.023). The 5- and 10-year survival rates were 88.9% and 76.2%, respectively. The risk factors for late deaths were old age (${\geq}50$ years, p=0.02) and low predicted postoperative forced expiratory volume in one second (FEV1) (< 1.2 L, p=0.02). Conclusion: Although PPE increases in patients with preoperative empyema and postoperative BPF increases in right-side operation, the mortality rates and long-term survival rates were found to be satisfactory. However, the follow-up care for patients with low predicted postoperative FEV1 should continue for prevention and early detection of pulmonary complication related to impaired pulmonary function.

• 생명과학회지
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• 제26권12호
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• pp.1392-1399
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• 2016

Jaspine B는 석회해면류에서 추출된 sphingosine유도체로 인간 암세포에서의 항암활성이 보고되었다. 그러므로 본 연구는 다양한 인간 암세포주에서 항암활성을 비교하고, 암세포주에서의 Jaspine B의 농도를 측정하여 항암 활성과의 연관성을 확인하고자 하였다. 항암활성은 MTT 방법을 이용하여 측정하였고, $EC_{50}$ 값으로 표현하였다. 암세포주내 Jaspine B의 농도는 LC-MS/MS를 이용하여 분석하였다. 항암활성은 세포주마다 다양하게 나타났는데, 유방암과 흑색종 세포주에서 항암활성이 높게 나타났으며($EC_{50}$ 각각 $2.3{\mu}M$과 $2.6{\mu}M$), 신장암세포주에서는 $EC_{50}$ 값이 $29.4{\mu}M$이었다. 암세포주에서의 $EC_{50}$ 값은 동일한 세포에서의 Jaspine B 농도와 높은 상관성을 나타내었으며(r=0.838), 암세포내 약물농도를 조절하는 것으로 잘 알려진 P-glycoprotein과 breast cancer resistance protein 등의 배출수송계와는 관련이 없음을 확인하였다. 이상의 결과는 세포내 약물농도를 높게 유지하는 것이 항암활성에 매우 중요하며, 세포내 약물농도가 암세포주에 따라 다른 약효를 보이는 원인으로 사료된다.

• 생명과학회지
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• 제25권7호
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• pp.833-838
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• 2015

다제약제 내성을 가지는 슈퍼 박테리아, 곰팡이, 바이러스, 기생충 감염은 주요한 건강위협인자들이다. 하지만, 건강위협 상황을 극복하기위해 현재 약제의 대안들중 항생펩타이드를 들 수 있다. 항생펩타이드는 자연계 다양한 종에서 생산된다. 항생펩타이드는 작은 단백질로 어류, 양서류, 파충류, 식물 그리고 동물의 감염으로부터 다세포생명체를 보호하는 선천성 면역에 관여하고 있다. 1980년대 이후로 매년 항생펩타이드의 수가 증가하고 있다. 박테리아, 원생생물, 곰팡이, 식물, 동물로부터 동정된 2,000가지 이상의 항생펩타이드가 항생펩타이드 데이터베이스에 등록되어 있다. 이러한 항생펩타이드의 대부분은 11-50개의 아미노산으로 구성되어 있고 하전상태는 0에서 +7까지이며 소수성은 31-70%를 차지하고 있다. 본 보고는 항생펩타이드를 생물학적 원천, 생물학적 기능, 펩타이드 성질, 공유결합패턴, 3차구조등에 의해 분류하였다. 항생펩타이드의 기능은 항균작용외에 세포주화성과 같은 세포생물학적 활성에도 기능성을 가지고 있다. 더욱이 림프절 스트로마로부터 기원한 fibroblastic reticular cell (FRC)에 염증상황 유도시 항생펩타이드가 발현되는 것을 확인하였다. FRC로부터 유도된 항생펩타이드는 whey acidic protein (WAP) 도메인을 포함하고 있었다. 이것은 단백질 도메인에 의해서도 항생펩타이드를 분류 할 수 있다는 것을 제시한다.

• Journal of Microbiology and Biotechnology
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• 제16권9호
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• pp.1377-1383
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• 2006

Among 46 Acinetobacter baumannii isolates collected in 2004, two imipenem-resistant isolates were obtained from clinical specimens taken from patients hospitalized in Busan, Republic of Korea. Two carbapenemase-producing isolates were further investigated to determine the mechanism of resistance. These isolates were analyzed by antibiotic susceptibility testing, microbiological tests of carbapenemase activity, determination of pI, transconjugation test, enterobacterial repetitive consensus (ERIC)-PCR, and DNA sequencing. Two cases of infection by A. baumannii producing the IMP-1 ${\beta}$-lactamase were detected. The isolates were characterized by a modified cloverleaf synergy test and EDTA-disk synergy test. Isoelectric focusing of crude bacterial extracts revealed nitrocefin-positive bands with a pI value of 9.0. PCR amplification and characterization of the amplicons by direct sequencing indicated that the isolates carried a $bla_{IMP-l}$ determinant. The isolates were characterized by a multidrug resistance phenotype, including penicillins, extended-spectrum cephalosporins, carbapenems, and aminoglycosides. These results indicate that the observed imipenem resistance of two Korean A. baumannii isolates was due to the spread of an IMP-1-producing clone. Our microbiological test of carbapenemase activity is simple to screen class B metallo-${\beta}$-lactamase-producing clinical isolates to determine their clinical impact and to prevent further spread. This study shows that the $bla_{IMP-l}$ resistance determinant, which is emerging in Korea, may become an emerging therapeutic problem, since clinicians are advised not to use extended-spectrum cephalosporins, imipenem, and aminoglycosides. This observation emphasizes the importance of having effective control measures in Asian hospitals, such as early detection of colonized patients, isolation procedures, and a judicious use of antibiotics.

• Tuberculosis and Respiratory Diseases
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• 제84권4호
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• pp.317-325
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• 2021

Background: Hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP) are significant public health issues in the world, but the epidemiological data pertaining to HAP/VAP is limited in Korea. The objective of this study was to investigate the characteristics, management, and clinical outcomes of HAP/VAP in Korea. Methods: This study is a multicenter retrospective cohort study. In total, 206,372 adult patients, who were hospitalized at one of the 13 participating tertiary hospitals in Korea, were screened for eligibility during the six-month study period. Among them, we included patients who were diagnosed with HAP/VAP based on the Infectious Diseases Society of America (IDSA)/American Thoracic Society (ATS) definition for HAP/VAP. Results: Using the IDSA/ATS diagnostic criteria, 526 patients were identified as HAP/VAP patients. Among them, 27.9% were diagnosed at the intensive care unit (ICU). The cohort of patients had a median age of 71.0 (range from 62.0 to 79.0) years. Most of the patients had a high risk of aspiration (63.3%). The pathogen involved was identified in 211 patients (40.1%). Furthermore, multidrug resistant (MDR) pathogens were isolated in 138 patients; the most common MDR pathogen was Acinetobacter baumannii. During hospitalization, 107 patients with HAP (28.2%) had to be admitted to the ICU for additional care. The hospital mortality rate was 28.1% in the cohort of this study. Among the 378 patients who survived, 54.2% were discharged and sent back home, while 45.8% were transferred to other hospitals or facilities. Conclusion: This study found that the prevalence of HAP/VAP in adult hospitalized patients in Korea was 2.54/1,000 patients. In tertiary hospitals in Korea, patients with HAP/VAP were elderly and had a risk of aspiration, so they were often referred to step-down centers.

• 대한임상검사과학회지
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• 제51권2호
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• pp.155-163
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• 2019

검사는 2010년부터 2017년까지 162,551 검체중 11,233 검체(6.9%)가 배양 양성이었으며, 이중 11,865 균주가 배양되었다. 배양된 균종 중 그람양성구균이 47.8%, 그람음성간균 38.8%, 그람양성간균 4.2%, 진균 6.8%, 혐기성균이 2.3%를 나타냈다. 배양결과를 성별로 비교하면 남성에서 분리된 균이 55.0% (2,732/4,969)로 여성에서 분리된 45.0% (2,237/4,969) 보다 많았다. 또한 연령별로는 70대가 28.7% (1,426/4,969)로 가장 많이 분리되었으며, 10대의 1.2% (62/4,969)와 많은 차이를 보였다. MRSA에 대한 내성률은 2016년 66.7%에서 2017년에는 46.8%로 많은 감소를 보였으며, E. faecium의 vancomycin 내성률은 35.0% (48/137)로 나타났다. 한편 장내세균에서 E. coli의 ESBL 양성률은 2010년 17.2%에서 2017년 28.8%로 증가하였으나, K. pneumoniae에서는 오히려 양성률이 감소하였다. P. aeruginosa의 MRPA는 11.8% (14/119), A. baumannii에서의 MRAB는 64.3% (161/252)로 높은 내성을 나타내었다. 혈액 검체에서 분리되는 미생물의 균종과 항균제 감수성 양상은 시기, 지역 및 대상환자 등에 따라 다르므로 병원균을 주기적으로 분석하고 이에 대한 항균제 감수성 정도의 변화양상을 파악하는 것이 병원에서 내성균의 감독과 조절에 큰 도움이 될 것으로 판단된다.