• Journal of Microbiology and Biotechnology
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• v.16 no.4
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• pp.623-632
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• 2006

To find potential targets of novel antimicrobial agents, we identified essential genes of Staphylococcus aureus N315 by using comparative genomics and allele replacement mutagenesis. By comparing the genome of S. aureus N315 with those of Bacillus subtilis, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, and Streptococcus pneumoniae, a total of 481 candidate target genes with similar amino acid sequences with at least three other species by >40% sequence identity were selected. of 481 disrupted candidate genes, 122 genes were identified as essential genes for growth of S. aureus N315. Of these, 51 essential genes were those not identified in any bacterial species, and 24 genes encode proteins of unknown function. Seventeen genes were determined as non-essential although they were identified as essential genes in other strain of S. aureus and other species. We found no significant difference among essential genes between Streptococcus pneumoniae and S. aureus with regard to cellular function.

• Parasites, Hosts and Diseases
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• v.47 no.3
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• pp.299-302
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• 2009

The incidence of imported malaria has been increasing in Korea. Were viewed data retrospectively to evaluate the epidemiology, clinical features, and outcomes of imported malaria from 1995 to 2007 in a university hospital. All patients diagnosed with imported malaria were included. Imported malaria was defined as a positive smear for malaria that was acquired in a foreign country. A total of 49 patients (mean age, 35.7 year; M: F = 38 : 11)were enrolled. The predominant malarial species was Plasmodium falciparum (73.5%), and the most frequent area of acquisition was Africa (55.1%), followed by Southeast Asia (22.4%) and South Asia (18.4%). Fourteen-patients (30.6%) suffered from severe malaria caused by P. falciparum and 1 patient (2.0%) died of multiorgan failure. Most of the patients were treated with mefloquine (79.2%) or quinine (10.2%); other antimalarial agents had to be given in 13.2% treated with mefloquine and 44.4% with quinine due to adverse drug events (ADEs). P. falciparum was the most common cause of imported malaria, with the majority of cases acquired from Africa, and a significant number of patients had severe malaria. Alternative antimalarial agents with lower rates of ADEs might be considered for effective treatment instead of mefloquine and quinine.

• Journal of Korean Neurosurgical Society
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• v.49 no.3
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• pp.186-189
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• 2011

In recent years the immunocompromised population has increased rapidly to include people with acquired immune deficiency syndrome (AIDS), drug abusers, and transplant patients. Accordingly, the incidence of intracranial fungal infection has increased. Our institution experienced 2 cases of internal carotid artery (ICA) occlusion due to invasion of the cavernous sinus by an intracranial fungal infection. The first case was a 60-year-old man who presented with headache, eye pain, conjunctival injection, right-sided diplopia, and blurred vision. Infected tissues within the frontal and ethmoid sinuses were removed via bifrontal craniotomy and endoscopic sinus surgery through the Caldwell Luc approach. The second case was a 63-year-old woman who developed right-sided facial pain after a tooth extraction. The infection was not controlled despite continuous use of antifungal agents, resulting in death from sepsis. We believe that when intracranial fungal infection is suspected in a patient with orbital symptoms and a focal neurologic deficit, immediate angiographic investigation of possible ICA occlusion is warranted. Aggressive treatment with antifungal agents is the only way to improve prognosis.

• Journal of Korean Neurosurgical Society
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• v.56 no.1
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• pp.21-27
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• 2014

Objective : Infectious spinal disease is regarded as an infection by a specific organism that affects the vertebral body, intervertebral disc and adjacent perivertebral soft tissue. Its incidence seems to be increasing as a result of larger proportion of the older patients with chronic debilitating disease, the rise of intravenous drug abuser, and the increase in spinal procedure and surgery. In Korea, studies assessing infectious spinal disease are rare and have not been addressed in recent times. The objectives of this study are to describe the epidemiology of all kind of spinal infectious disease and their clinical and microbiological characteristics as well as to assess the diagnostic methodology and the parameters related to the outcomes. Methods : A retrospective study was performed in all infectious spinal disease cases presenting from January 2005 to April 2010 to three tertiary teaching hospitals within a city of 1.5 million in Korea. Patient demographics, risk factors, clinical features, and outcomes were assessed. Risk factors entailed the presence of diabetes, chronic renal failure, liver cirrhosis, immunosuppressants, remote infection, underlying malignancy and previous spinal surgery or procedure. We comparatively analyzed the results between the groups of pyogenic and tuberculous spinal infection. SPSS version 14 statistical software was used to perform the analyses of the data. The threshold for statistical significance was established at p<0.05. Results : Ninety-two cases fulfilled the inclusion criteria and were reviewed. Overall, patients of tuberculous spinal infection (TSI) and pyogenic spinal infection (PSI) entailed 20 (21.7%) and 72 (78.3%) cases, respectively. A previous spinal surgery or procedure was the most commonly noted risk factor (39.1%), followed by diabetes (15.2%). The occurrence of both pyogenic and tuberculous spondylitis was predominant in the lumbar spine. Discs are more easily invaded in PSI. At initial presentation, white cell blood count and C-reactive protein levels were higher in PSI compared to TSI (p<0.05). Etiological agents were identified in 53.3%, and the most effective method for identification of etiological agents was tissue culture (50.0%). Staphyococcus aureus was the most commonly isolated infective agent associated with pyogenic spondylitis, followed by E. coli. Surgical treatment was performed in 31.5% of pyogenic spondylitis and in 35.0% of tuberculous spondylitis cases. Conclusion : Many previous studies in Korea usually reported that tuberculous spondylitis is the predominant infection. However, in our study, the number of pyogenic infection was 3 times greater than that of tuberculous spinal disease. Etiological agents were identified in a half of all infectious spinal disease. For better outcomes, we should try to identify the causative microorganism before antibiotic therapy and make every effort to improve the result of culture and biopsy.

• Pediatric Infection and Vaccine
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• v.16 no.1
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• pp.6-12
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• 2009

There are relatively few novel antimicrobial agents despite the dramatic increase in antimicrobial resistance and multiple drug resistance of clinical isolates worldwide. Vancomycin is still the most widely used antibiotic for treating resistant Gram-positive coccal infections in children, especially for methicillin-resistant Staphylococcus aureus. For children with Gram-positive coccal infections where vancomycin is not effective or older therapeutic agents cannot be tolerated, linezolid, quinupristin-dalfopristin or daptomycin may be useful in the appropriate clinical setting. For Gram-negative bacterial infections, new carbapenems await clinical application. Tebipenem pivoxil is a novel oral carbapenem undergoing clinical trials for acute otitis media in pediatric patients. Antiviral drug development is now progressing at the pace of antibiotic development 30 years ago. Newer antiviral agents used for the treatment of herpes viruses and hepatitis C virus infections in children are included in this review.

• Journal of Microbiology and Biotechnology
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• v.23 no.9
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• pp.1322-1326
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• 2013

New antifungal agents are required to compensate for the increase in resistance to standard antifungal agents of Candida albicans, which is an important opportunistic fungal pathogen that causes minor infections in many individuals but very serious infections in those who are immune-compromised. In this study, combinations of theaflavin and epicatechin are investigated as potential antifungal agents and also to establish whether antifungal synergy exists between these two readily accessible and cost-effective polyphenols isolated from black and green tea. The results of disc diffusion assays showed stronger antibacterial activity of theaflavin:epicatechin combinations against C. albicans NCTC 3255 and NCTC 3179, than that of theaflavin alone. Minimum inhibitory concentrations (MICs) of 1,024 ${\mu}g/ml$ with theaflavin and 128-256 ${\mu}g/ml$ with theaflavin:epicatechin combinations were found. The fractional inhibitory concentration indexes were calculated, and the synergy between theaflavin and epicatechin against both isolates of C. albicans was confirmed. Theaflavin:epicatechin combinations show real potential for future use as a treatment for infections caused by C. albicans.

• Korean Journal of Veterinary Research
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• v.20 no.2
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• pp.159-165
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• 1980

A total of 98 strains of Bordetella bronckiseptica isolated from pigs affected the infectious atrophic rhinitis(AR) during 1978 were surveyed for drug sensitivity to 26 chemotherapeutic agents, and minimum inhibitory concentration(MIC), incidence rate of resistant strain and resistant patern from the strains which were obtained from the different pig farm in Jeonnam province were examined. The results obtained are summarized as follows. 1. Most of the strains tested were resistant to Ampicillin (AB, PC), spiramycin(SPO, sulfa drugs (SD) (MIC:$400.0{{\mu}g/ml}$) and streptomycin(SM) (MIC:$200.0{{\mu}g/ml}$). Of the 75.0% of strains were also resistant to penicillin(PC) (MIC:$200.0{{\mu}g/ml}$) and of the 14.3 of strains were inhibited to grow to tetracycline(TC), chlortetracycline(CTC), oxytetracyc-line(OTC), erythromycin(EM), tylosin(TS), leucomycin (LM) and chloramphenicol (CP) (MIC:$6.25{{\mu}g/ml}$). On the other hand, most of the strains tested were inhibited to grow to kanamycin(KM), gentamycin(GM) neomycin(NM) (MIC:$25.0{{\mu}g/ml}$) and to colistin(CL) (MIC:$12.5{{\mu}g/ml}$). 2. Incidence rate of resistant strains to main chemotherapeutic agents was 100.0% of sulfa drugs, 96.4% of streptomycin, 85.7% of penicillin, tetracycline, chloramphenicol and erythromycin, 46.4% of gentamycin, 17.9% of colistin and 0.0% of kanamycin and nalidixic acid.

• Food Science and Biotechnology
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• v.17 no.5
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• pp.1074-1078
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• 2008

To investigate the antiviral activity of marine algae against fish pathogenic viruses, which are often the causes of viral disease in aquaculture, the 80% methanolic extracts of 21 species collected from the coast of Korea were screened for their in vitro antiviral activities on infectious hematopoietic necrosis virus (IHNV) and infectious pancreatic necrosis virus (IPNV), using a flounder spleen (FSP) cell-line. Among them, Monostroma nitidum (10 ${\mu}g/mL$) exhibited the strongest inactivation on IHNV, showing a 2 log reduced virus titre as compared to the control in the determination of direct virucidal activity. In addition, Polysiphonia morrowii (100 ${\mu}g/mL$) remarkably reduced the virus titres of treated cells by 2-2.5 log, for both IHNV and IPNV, in the determination of cellular protective activity, implying the existence of substances that may modulate innate host defense mechanisms against viral infections. These results reveal that some marine algae could be promising candidates as sources of antiviral agents or as health-promoting feeds for aquaculture.

• The Journal of the Korean Society for Microbiology
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• v.35 no.5_6
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• pp.372-372
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• 2000

• Pediatric Infection and Vaccine
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• v.15 no.2
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• pp.100-107
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• 2008

Acute otitis media and acute sinusitis are some of the most common antibiotic-prescribed diseases in childhood. Usually, with an accurate diagnosis, a 10-14 day course of antibiotics is recommended to cover common causative agents, including pneumococci. Establishment of management guidelines for these infectious diseases based on further study of the epidemiologic profile, antibiotic resistance, and clinical circumstances in Korea is needed.