• 한국축산식품학회지
• /
• 제31권1호
• /
• pp.47-53
• /
• 2011

Salmonella enterica serovar Typhimurium (ST) is one of the most common serovars isolated from humans and animals. It has been suggested that ST infections in Koreans are largely due to the consumption of contaminated pork and beef. To investigate the genotypes, phage types, and antimicrobial resistance patterns for ST isolates of different origins, a total of 70 ST strains, including 19 isolates from humans, 44 isolates from pigs, and 6 isolates from cattle, were analyzed using pulsedfield gel electrophoresis (PFGE), phage typing, and antimicrobial susceptibility tests. Forty-three distinct PFGE patterns were generated from 70 ST isolates, which were grouped into 14 PFGE groups (from A to N) at the level of 75% similarity. The most prevalent group was the A (A1-A17 subtypes) group, encompassing 54.5% (38/70) of ST isolates. ST isolates from pigs and cattle mostly belong to groups A and L, whereas ST isolates from humans mostly belong to groups F and C. Antimicrobial susceptibility tests using 11 antimicrobial agents showed that resistance to tetracycline (TE) (81.4%) was highly prevalent, followed by streptomycin (S) (64.3%) and nalidixic acid (NA) (31.4%) resistance. A total of seventeen antimicrobial resistance patterns were observed. Only 8.6% of isolates, including a reference strain, were susceptible to all antimicrobial agents tested. The most prevalent resistance pattern was TE-S (37.1%), which was seen in 66.6% of bovine, 40.8% of swine and 21.1% of human isolates. Three ST isolates from humans (15.9%) showed resistance to 7-8 antimicrobials. The most predominant phage type (PT) was U302 (64.3%), followed by DT170 (10.0%). PFGE types did not coincide with antimicrobial resistance patterns and phage types; therefore, the combination of those types allowed for further differentiation between tested ST isolates.

• 한국미생물생명공학회:학술대회논문집
• /
• 한국미생물생명공학회 2000년도 Proceedings of 2000 KSAM International Symposium and Spring Meeting
• /
• pp.3-6
• /
• 2000

Antimicrobial resistance has been a well-recognized problem ever since the introduction of penicillin into clinical use. History of antimicrobial development can be categorized based on the major antibiotics that had been developed against emerging resistant $pathogens^1$. In the first period from 1940 to 1960, penicillin was a dominating antibiotic called as a "magic bullet", although S.aureus armed with penicillinase led antimicrobial era to the second period in 1960s and 1970s. The second stage was characterized by broad-spectrum penicillins and early generation cephalosporins. During this period, nosocomial infections due to gram-negative bacilli became more prevalent, while those caused by S.aureus declined. A variety of new antimicrobial agents with distinct mechanism of action including new generation cephalosporins, monobactams, carbapenems, ${\beta}$-lactamase inhibitors, and quinolones characterized the third period from 1980s to 1990s. However, extensive use of wide variety of antibiotics in the community and hospitals has fueled the crisis in emerging antimicrobial resistance. Newly appeared drug-resistant Streptococcus pneumoniae (DRSP), vancomycin-resistant enterococci (VRE), extended-spectrum ${\beta}$-lactamase-producing Klebsiella, and VRSA have posed a serious threat in many parts of the world. Given the recent epidemiology of antimicrobial resistance and its clinical impact, there is no greater challenge related to emerging infections than the emergence of antibiotic resistance. Problems of antimicrobial resistance can be amplified by the fact that resistant clones or genes can spread within or between the species as well as to geographically distant areas which leads to a global concern$^2$. Antimicrobial resistance is primarily generated and promoted by increased use of antimicrobial agents. Unfortunately, as many as 50 % of prescriptions for antibiotics are reported to be inappropriate$^3$. Injudicious use of antibiotics even for viral upper respiratory infections is a universal phenomenon in every part of the world. The use of large quantities of antibiotics in the animal health industry and farming is another major factor contributing to selection of antibiotic resistance. In addition to these background factors, the tremendous increase in the immunocompromised hosts, popular use of invasive medical interventions, and increase in travel and mixing of human populations are contributing to the resurgence and spread of antimicrobial resistance$^4$. Antimicrobial resistance has critical impact on modem medicine both in clinical and economic aspect. Patients with previously treatable infections may have fatal outcome due to therapeutic failure that is unusual event no more. The potential economic impact of antimicrobial resistance is actually uncountable. With the increase in the problems of resistant organisms in the 21st century, however, additional health care costs for this problem must be enormously increasing.

• Pediatric Infection and Vaccine
• /
• 제24권2호
• /
• pp.87-94
• /
• 2017

목적: 상기도 감염인 소아에게 항생제를 처방하는 것은 아직도 많은 진료실에서 이루어지고 있다. 이 연구는 역전사 중합효소연쇄반응 검사로 호흡기 바이러스가 확인된 이후에도 항생제를 사용한 소아 환자들의 임상적 특징을 조사하고자 하였다. 방법: 2013년 1월부터 2014년 11월에 고신대학교 복음병원 소아청소년과에 상기도 감염으로 입원한 환자 중 역전사 중합효소연쇄반응을 시행한 환자들을 대상으로 후향적 의무기록 분석을 통해 평가하였다. 결과: 상기도 감염으로 진단받은 393명 중 전체 환자 연령의 중앙값은 23개월이었다. 입원 당시 항생제를 처방받은 환자(79명, 20.1%)와 항생제를 처방받지 않은 환자들의 임상적 요인을 비교할 때, 중이염 또는 부비동염의 동반, 높은 고감도 C-반응단백질의 수치가 항생제 처방과 의미 있게 관련 있었다(P<0.001). 입원하여 항생제를 사용하던 중 역전사 중합효소연쇄반응 방법으로 호흡기 바이러스가 확인되었지만, 항생제를 계속 사용한 환자는 44명 중 28명(63.6%)이었다. 항생제를 계속 사용한 환자는 항생제를 중단한 환자와 비교할 때 중이염 동반 비율이 유의하게 높았다(75% vs. 25%, P=0.002). 결론: 본 연구에서 상기도 감염의 원인이 바이러스임을 확인된 소아 환자에게서도 항생제를 지속한 주된 이유는 중이염이 동반되었기 때문이었다. 중이염을 정확하게 진단하고 그 중 항생제가 꼭 필요한 경우를 가려낸다면 소아 상기도 감염에서 불필요한 항생제 사용을 줄이는 데 도움이 될 것으로 생각된다.

• 대한수의학회지
• /
• 제38권4호
• /
• pp.763-770
• /
• 1998

Salmonella typhimurium is a causitive agent of diarrhea, fever, gastroenteritis, septicemia and sudden death in piglet. The currently used methods such as IFA, ELISA, DNA hybridization assay is needed a long-time and difficult to detect the organism in carrier animal or contaminated sample with other agents. However, it is important to detect rapidly and sensitively S typhimurium in piglet with other infectious pathogens to minimize an economic loss. Two sets of PCR primer, rfbJ forward primer(5'-AGAATATGTAATTGTCAG-3') and reverse primer(5'-TAACCGTTTCAGTAGTTC-3') were designed to amplify a 882 by fragment of Salmonella serovar type B gene. The target genomic DNA for PCR was extracted from the cultivated materials with various enrichment periods in a nonselective enrichment agar and broth with clinical specimens. The PCR is carried out here made it possible to detect the gene from two hours. Also, the amplified fragment with PCR was cloned into pGEM-T vector and digested with restrict enzyme, and sequenced for the identification of Salmonella serotype B rfbJ gene. Duplicated cultivation agar-broth followed by PCR were performed to develop a rapid and sensitive detection of S typhlmurium based on serovar type. This duplicated cultivation-PCR method provides a sensitive and rapid diagnostic tool to detect Salmonella from infected piglet with improved sensitivity.

• Pediatric Infection and Vaccine
• /
• 제14권1호
• /
• pp.124-128
• /
• 2007

폐쇄 세기관지염은 아데노바이러스, 인플루엔자, 파라인플루엔자, 홍역바이러스, 폐렴미코플라스마, 호흡기 세포융합바이러스 등에 의해서 생길 수 있다. 특히 3, 7, 21형 아데노바이러스의 경우에는 급성기의 심한 폐증상을 일으킬 뿐만 아니라 만성적인 합병을 남길 수 있다. 이에 7형 아데노바이러스에 의한 심한 폐렴 후, 만성적인 기침 및 호흡기 증상을 가진 환아를 HRCT를 통해 폐쇄 세기관지염으로 진단하였고, 이후 흡입 스테로이드와 흡입 기관지확장제를 통해 증상을 조절한 1례를 경험한 바 문헌 고찰과 함께 보고하는 바이다.

• Journal of Ginseng Research
• /
• 제44권3호
• /
• pp.506-518
• /
• 2020

Background: Red-skin root of Asian ginseng (Panax ginseng) significantly reduces the quality and limits the production of ginseng in China. The disease has long been thought to be a noninfectious physiological disease, except one report that proved it was an infectious disease. However, the causal agents have not been successfully determined. In the present study, we were to reveal the pathogens that cause red-skin disease. Methods: Ginseng roots with red-skin root symptoms were collected from commercial fields in Northeast China. Fungi were isolated from the lesion and identified based on morphological characters along with multilocus sequence analyses on internal transcription spacer, β-tubulin (tub2), histone H3 (his3), and translation elongation factor 1α (tef-1α). Pathogens were confirmed by inoculating the isolates in ginseng roots. Results: A total of 230 isolates were obtained from 209 disease samples. These isolates were classified into 12 species, including Dactylonectria sp., D. hordeicola, Fusarium acuminatum, F. avenaceum, F. solani, F. torulosum, Ilyonectria mors-panacis, I. robusta, Rhexocercosporidium panacis, and three novel species I. changbaiensis, I. communis, and I. qitaiheensis. Among them, I. communis, I. robusta, and F. solani had the highest isolation frequencies, being 36.1%, 20.9%, and 23.9%, respectively. All these species isolated were pathogenic to ginseng roots and caused red-skin root disease under appropriate condition. Conclusion: Fungal complex is the causal agent of red-skin root in P. ginseng.

• Asian Pacific Journal of Cancer Prevention
• /
• 제17권5호
• /
• pp.2423-2428
• /
• 2016

Gastric cancer (GC) is a multifactorial disease with different factors having roles in its genesis. Helicobacter pylori and Epstein-Barr virus (EBV) are known infectious agents that could contribute. In addition, there is evidence of a relationship with cytomegalovirus (CMV). Since data on CMV prevalence in gastric cancer are limited, we here evaluated the frequency of EBV and CMV in Iranian patients. Ninety paraffin blocks of GC tissues from patients in Kerman were evaluated for the presence of EBV and CMV genomes by real-time polymerase chain reaction. EBV was detected in 10 cases (11.1%) and CMV in seven. One out of 17 female patients (5.88%) and nine out of 73 male patients (12.3%) were positive for EBV, while one out of 17 female patients (5.88%) and six out of 73 male patients (8.22%) were positive for CMV. The mean age for EBV-positive patients was $60.5{\pm}14.9years$ and the mean age for CMV-positive patients was $67.9{\pm}12.3years$. This study shows that the frequency of EBV-associated GC is high in Kerman. It also indicates that further studies of associations between GC and CMV are warranted, covering larger samples and populations from different areas of the world.

• 한국환경보건학회지
• /
• 제31권3호
• /
• pp.199-206
• /
• 2005

C. neoformans-associated cryptococcosis is primarily a disease of immunocompromised persons, has a world-wide distribution, and is often spread by pigeons in the urban environment. In contrast, C. gattii causes infection in normal hosts, has only been described in tropical and semi-tropical areas of the world, and has a unique niche in river gum Eucalyptus trees. Cryptococcosis is acquired through inhalation of the yeast propagules from the environment. C. gattii has been identified as the cause of an emerging infectious disease centered on Vancouver Island, British Columbia, Canada. No cases of C. gattii-disease were diagnosed prior to 1999; the current incidence rate is 36 cases per million population. A search was initiated in 2001 to find the ecological niche of this basidiomycetous yeast. C. gattii was found in the environment in treed areas of Vancouver Island. The highest percentage of colonized-tree clusters were found around central Vancouver Island, with decreasing rates of colonization to the north and south. Climate, soil and vegetation cover of this area, called the Coastal Douglas fir biogeoclimatic zone, is unique to British Columbia and Canada. The concentration of airborne C. gattii was highest in the dry summer months, and lowest during late fall, winter, and early spring, months which have heavy rainfall. The study of the emerging colonization of this organism and subsequent cases of environmentally acquired disease will be informative in planning public health management of new routes of exposure to exotic agents in areas impacted by changing climate and land use patterns.

• Tuberculosis and Respiratory Diseases
• /
• 제83권1호
• /
• pp.1-13
• /
• 2020

For the past three decades, more than a thousand of genetic studies have been performed to find out the genetic variants responsible for the risk of asthma. Until now, all of the discovered single nucleotide polymorphisms have explained genetic effects less than initially expected. Thus, clarification of environmental factors has been brought up to overcome the 'missing' heritability. The most exciting solution is epigenesis because it intervenes at the junction between the genome and the environment. Epigenesis is an alteration of genetic expression without changes of DNA sequence caused by environmental factors such as nutrients, allergens, cigarette smoke, air pollutants, use of drugs and infectious agents during pre- and post-natal periods and even in adulthood. Three major forms of epigenesis are composed of DNA methylation, histone modifications, and specific microRNA. Recently, several studies have been published on epigenesis in asthma and allergy as a powerful tool for research of genetic heritability in asthma albeit epigenetic changes are at the starting point to obtain the data on specific phenotypes of asthma. In this presentation, we mainly review the potential role of DNA CpG methylation in the risk of asthma and its sub-phenotypes including nonsteroidal anti-inflammatory exacerbated respiratory diseases.

• 대한약침학회지
• /
• 제16권2호
• /
• pp.15-22
• /
• 2013

Objective: Evaluations of the in-vitro anti-bacterial activities of aqueous extracts of Acacia catechu (L.F.)Willd, Castanea sativa, Ephedra sinica stapf and Shilajita mumiyo against gram-positive bacteria (Staphylococcus aureus, Streptococcus pneumonia) and gram-negative bacteria (Escherichia coli, klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa) are reasonable since these ethnomedicinal plants have been used in Persian folk medicine for treating skin diseases, venereal diseases, respiratory problems and nervous disorders for ages. Methods: The well diffusion method (KB testing) with a concentration of $250{\mu}g/disc$ was used for evaluating the minimal inhibitory concentrations (MIC). Maximum synergistic effects of different combinations of components were also observed. Results: A particular combination of Acacia catechu (L.F.) Willd, Castanea sativa, Ephedra sinica stapf and shilajita mumiyo extracts possesses an outstanding anti-bacterial activity. It's inhibiting effect on microorganisms is significant when compared to the control group (P<0.05). Staphylococcus aureus was the most sensitive microorganism. The highest anti-bacterial activity against gram-positive bacteria (Staphylococcus aureus, Streptococcus pneumonia) or gram-negative bacteria (Escherichia coli, Klebsiella pneumonia, Proteus mirabilis, and Pseudomonas aeruginosa) was exerted by formula number 2 (table 1). Conclusion: The results reveal the presence of anti-bacterial activities of Acacia catechu, Castanea sativa husk, Ephedra sp. and Mumiyo against gram-positive and gram-negative bacteria. Synergistic effects in a combined formula, especially in formula number 2 (ASLAN$^{(R)}$) can lead to potential sources of new antiseptic agents for treatment of acute or chronic skin ulcers. These results considering the significant anti-bacterial effect of the present formulation, support ethnopharmacological uses against diarrheal and venereal diseases and demonstrate use of these plants to treat infectious diseases.