Pseudo-outbreak of Brevundimonas diminuta

Brevundimonas diminuta is a lactose non-fermenting Gram-negative rod associated with infection in immunocompromised patients. In three patients from two general wards, B. diminuta was isolated in blood culture sample. The clinical features of the patients did not coincide with the blood culture result, and pseudo-outbreak was suspected. These isolated were biochemically identified as Brevundimonas diminuta, and 16S rRNA sequencing confirmed their identification. The PFGE result showed a single pattern, and their clonality was assumed.ope

Evaluation of Rapid Assay (Toc A/B Quik Chek) for the Detection of Clostridium difficile Toxins A and B

Background: Toxin immunoassay is widely used for rapid diagnosis of Clostridium difficile-associated diarrhea. The aim of this study was to evaluate the performance of Tox A/B Quik Chek test (TECHLAB, Blacksburg, VA, USA) compared to toxigenic culture. Methods: From September 2006 to August 2007, 959 stools were examined by Tox A/B Quik Chek test and toxigenic culture (C. difficile culture plus tcdB PCR using colonies obtained from culture). Results: Compared to the results of toxigenic culture, the sensitivity and specificity of Tox A/B Quik Chek test were 47.5% and 97.5%, respectively. Conclusion: The sensitivity of Tox A/B Quik Chek test was not high, but the specificity was high. Although Tox A/B Quik Chek test alone is not sufficient to diagnose Clostridium difficile-associated diarrhea, it may aid rapid diagnosis, early treatment and prevention of nosocomial spread of the infection, if supplemented by C. difficile culture or tissue culture cytotoxin assay.ope

Two Cases of Clostridium citroniae Bacteremia in Cancer Patients

Clostridium citroniae is a novel species reclassified from C. clostridioforme. Clostridium species are obligate anaerobes and spore-forming gram-positive rods. However, C. citroniae stains gram negative and does not consistently produce spores, making it difficult to identify. We isolated C. citroniae from the blood and peritoneal fluid of one patient, and from the blood of another patient, both of whom were undergoing cancer chemotherapy.ope

김치의 ethyl carbamate 측정

학위논문(석사)--서울대학교 대학원 :식품영양학과,1995.Maste

Ca2+ influx through the carbachol-activated nonselective cation channel in guinea-pig gastric myocyte

학위논문(박사)--서울대학교 대학원 :의학과 생리학전공,1998.Docto

Climatic and chemical factors on ethyl carbamate formation in Korean soysauce

학위논문(박사)--서울대학교 대학원 :식품영양학과,2003.Docto

Analysis of blood culture results at the Severance Hospital during 1994-2003

의학과/석사[한글]균혈증은 가장 위중한 감염증 중의 한가지이므로 혈액에서 병원체를 신속하게 검출하는 일은 질병의 진단, 예후판단 및 치료지침을 세우는데 매우 중요하다. 혈액배양에서 분리되는 균종과 항균제 감수성 양상은 시기, 지역 및 대상환자 등에 따라 다르므로 이를 분석하는 일은 환자의 경험적 치료를 위한 중요한 자료가 된다. 본 연구에서는 1994-2003년간의 세브란스 병원 입원 및 외래환자의 혈액배양 결과와 항균제 감수성 결과를 후향적으로 분석하였다.이 기간 동안 535,916 검체의 혈액이 배양되어 24,877 검체 (4.6%)가 배양 양성이었으며 양성 환자수는 13,102명이었다. 분리된 균종 중 호기성 세균이 93.1%, 혐기성 세균이 3.3%, 진균이 3.6%이었다. 흔히 분리된 균종으로는 Escherichia coli, Staphylococcus aureus, -hemolytic Streptococcus, Enterococcus, Klebsiella pneumoniae, Enterobacter, Pseudomonas aeruginosa 순이었다.연도별 분리율은 E. faecium이 3.6%에서 10.1%로 증가하였고, K. pneumoniae는 7.5%에서 13.0%로 증가하였다. -hemolytic Streptococcus와 E. coli는 분리수가 증가하였으나 분리율은 비슷하였다. 연령군별로는 50세 이상 군에서 균혈증이 많았으며 2세 미만 군에서는 Enterococcus와 α-hemolytic Streptococcus의 분리가 많았다. 50세 이상 군에서는 Enterobacteriaceae와 포도당 비발효 그람음성 간균의 분리가 많았다. 다균성 균혈증은 전체 세균배양 양성 환자 중 2.6%를 차지하였다.항균제 감수성 시험 결과에서 S. pneumoniae의 penicillin G 비감수성율은 현저히 증가한 반면 S. aureus의 oxacillin 내성은 감소하였고, vancomycin에 내성인 S. aureus는 없었으나, vancomycin에 내성인 E. faecium이 현저히 증가하였다. 제3세대 cephalosporin제에 내성인 E. coli와 K. pneumoniae는 각각 10%와 30% 내외이었으며, imipenem에 내성인 P. aeruginosa와 A. baumannii 는 현저히 증가하였다.이 연구에서 균혈증 환자에서 가장 흔히 분리되는 것은 E. coli이며 S. aureus, -hemolytic Streptococcus, Enterococcus, Klebsiella pneumoniae가 변함없이 흔히 분리되는 원인균이며, Enterococcus에 의한 균혈증과 진균에 의한 균혈증 특히 C. albicans 가 아닌 Candida 균종에 의한 균혈증이 증가하고 있으며 vancomycin에 내성인 E. faecium과 imipenem에 내성인 P. aeruginosa와 A. baumannii 가 증가하고 있다는 결론을 얻었다. [영문]Blood culture is an important procedure for the determination of the etiologic agent of bacteremia. Analysis of blood culture results and antimicrobial susceptibility trend can provide the clinicians with relevant information for the empirical treatment of patients. In this study, the results of both the species and antimicrobial susceptibility of the isolates at the Severance Hospital during the years 1994-2003 were analyzed.During the study period, a total of 536,916 blood specimens were cultured, and 24,877 positive specimens were obtained from 13,102 patients. Among the isolates, 93.1% were aerobic or facultative anaerobic bacteria, 3.3% anaerobes, and 3.6% fungi.E. coli was isolated most frequently, followed by Staphylococcus aureus, -hemolytic Streptococcus, Enterococcus, Klebsiella pneumoniae, Enterobacter and Pseudomonas aeruginosa.The proportion of patients with E. faecium increased from 3.6% in 1994 to 10.1% in 2003, and those with K. pneumoniae increased from 7.5% in 1994 to 13.0% in 2003.-hemolytic Streptococcus was frequently isolated from the age group of less than 2 years, Enterobacteriaceae and glucose-nonfermenting gram-negative bacilli from the age group of more than 50 years.Polyclonal bacteremia was found in 2.6% of patients with positive blood cultures. The organisms frequently involved were E. coli, S. aureus, K. pneumoniae and Enterococcus.Penicillin-nonsusceptible S. pneumoniae, vancomycin-resistant E. faecium, imipenem-resistant P. aeruginosa and A. baumannii increased, but oxacillin-resistant S. aureus decreased significantly during the study period.It is concluded from the study that E. coli is the most common cause of bacteremia and that S. aureus, -hemolytic Streptococcus and Klebsiella pneumoniae remains to be frequently isolated pathogens. The bacteremia due to Enterococcus and fungi has increased. The proportion of non-albicans Candida species among Candida species increased. More frequent resistance of S. pneumoniae, E. faecium, P. aeruginosa and A. baumannii become problems in the selection of antimicrobial agent.ope

1999~2008년 명문대-비명문대 임금격차의 변화

학위논문(석사)--서울대학교 대학원 :경제학부,2011.2. 이철희.Maste

요 검체에서 분리된 대장균의 항균제 내성 기전

BACKGROUND: This study was designed to characterize urinary isolates of Escherichia coli that produce extended-spectrum beta-lactamases (ESBLs) and to determine the prevalence of other antimicrobial resistance genes. METHODS: A total of 264 non-duplicate clinical isolates of E. coli were recovered from urine specimens in a tertiary-care hospital in Busan in 2005. Antimicrobial susceptibility was determined by disk diffusion and agar dilution methods, ESBL production was confirmed using the double-disk synergy (DDS) test, and antimicrobial resistance genes were detected by direct sequencing of PCR amplification products. E. coli isolates were classified into four phylogenetic biotypes according to the presence of chuA, yjaA, and TSPE4. RESULTS: DDS testing detected ESBLs in 27 (10.2%) of the 264 isolates. The most common type of ESBL was CTX-M-15 (N=14), followed by CTX-M-3 (N=8) and CTX-M-14 (N=6). All of the ESBL-producing isolates were resistant to ciprofloxacin. PCR experiments detected genes encoding DHA-1 and CMY-10 AmpC beta-lactamases in one and two isolates, respectively. Also isolated were 5 isolates harboring 16S rRNA methylases, 2 isolates harboring Qnr, and 19 isolates harboring AAC(6')-Ib-cr. Most ESBL-producing isolates clustered within phylogenetic groups B2 (N=14) and D (N=7). CONCLUSION: CTX-M enzymes were the dominant type of ESBLs in urinary isolates of E. coli, and ESBL-producing isolates frequently contained other antimicrobial resistance genes. More than half of the urinary E. coli isolates harboring CTX-M enzymes were within the phylogenetic group B2ope