• Biomedical Science Letters
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• v.27 no.4
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• pp.323-328
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• 2021

Naegleria fowleri is a free-living amoeba causing primary amoebic encephalitis. In this study, we analyzed how the N-aceytlglucosamine (GlcNAc) and D-galactose affected the interaction between Naegleria fowleri and methicillin-resistant Staphylococcus aureus (MRSA) or Escherichia coli O157:H7, and the interaction with bacteria when monosaccharides were treated with N. fowleri for a longer pre-incubation time. When GlcNAc was treated with N. fowleri for 1 hr, the E. coli association was almost the same as that of the control not treated with GlcNAc until the concentration of GlcNAc was 25 mM. However, the E. coli association was reduced by approximately 91% with 100 mM GlcNAc. E. coli invasion into N. fowleri showed statistical significance only in the group treated with 100 mM GlcNAc. The interaction when treated with galactose showed a very different pattern in the 50 mM galactose group than when treated with GlcNAc. In the MRSA interaction, a statistically significant decrease in association (76.3% by GlcNAc and 88.7% by galactose) and invasion (3.6% by GlcNAc and 9.3% by galactose) was shown by the concentration of two 100 mM monosaccharides. The group treated with monosaccharides at the same time showed almost no difference in all interactions from the group treated with monosaccharides at the same time. Taken together, it suggested that the effect of monosaccharides on the interaction of several Gram-negative or positive bacteria and the evidence that the interaction could be enhanced by longer pre-incubation time.

• Journal of Environmental Health Sciences
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• v.38 no.3
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• pp.213-222
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• 2012

Objectives: This study was undertaken in order to evaluate by work space zoning and structure the concentrations of biological contaminants in the indoor air of domestic office buildings. Methods: Air samples were collected in the office spaces of 15 office buildings in Seoul from June 28 to July 28, 2011. Prior to the sampling, each office was classified into 'open-plan office', 'cellular office' and 'mixed office' according to the work space zoning. To evaluate the biological contamination of indoor air, total suspended bacteria (TSB), Gram positive bacteria (GPB), Staphylococcus aureus (S.A), Methicillin-resistant Staphylococcus aureus (MRSA), Gram negative bacteria (GNB) and fungi were investigated. During the sampling, temperature, relative humidity and carbon dioxide ($CO_2$) were measured. Results: The TSB concentrations ($GM{\pm}GSD$) were $452({\pm}1.3)cfu/m^3$ in open-plan offices, $366({\pm}1.3)cfu/m^3$ in cellular offices and $287({\pm}1.5)cfu/m^3$ in mixed offices, and there were significant differences between the three groups (p<0.05). The highest concentrations ($GM{\pm}GSD$) of fungi were found in the indoor air of cellular offices $128({\pm}1.0)cfu/m^3$, which was at least three times higher than the concentrations in mixed offices $43({\pm}1.0)cfu/m^3$ (p<0.05). Conclusions: Microbiological contamination in the indoor air of office buildings by work space structure was the highest with the open-plan office layout which includes no high walls or doors separating the occupants.

• Journal of Environmental Health Sciences
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• v.40 no.4
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• pp.304-312
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• 2014

Objectives: This study was performed to examine bioaerosols in indoor air in public restrooms, as well as to assess the effects of air temperature and relative humidity on bioaerosol levels. Methods: A cross-sectional survey was performed in ten male and ten female restrooms. An air sampler (Anderson type) was used for sampling total suspended bacteria (TSB), Gram-negative bacteria (GNB), Gram-positive bacteria (GPB), opportunistic bacteria (OP), Staphylococcus spp., and total suspended fungi (TSF). Results: The levels of TSB were $10-10^2CFU/m^3$ and TSF $10-10^2CFU/m^3$, respectively. The GNB level was $0-10CFU/m^3$, and GPB and OP levels were $10-10^2CFU/m^3$. Staphylococcus aureus and methicillin-resistant S. aureus (MRSA) were detected in 90% of the restrooms. The GPB level was higher in the female restrooms than in the male restrooms (p < 0.05). TSB, GNB, and TSF showed higher levels in restrooms in buildings over 30 years old (p < 0.01). The main effect of air temperature or relative humidity and interaction effect of the two factors on the TSB level were significant (p < 0.05), while the effect of relative humidity on the TSF level was significant (p < 0.001). Conclusions: These results indicate that there is a wide variation in the bioaerosol levels among different restrooms. The observed differences in bioaerosol levels reflect different building histories. The effects of air temperature and/or relative humidity reveal that bioaerosol levels may vary according to season or time of day. Future research is needed to further characterize the relation between the bioaerosol levels and surface contamination in restrooms.

• Biomolecules & Therapeutics
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• v.4 no.4
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• pp.378-384
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• 1996

In vitro activities of LB20304a were compared with those of grepafloxacin (OPC-17116), Q-35, ciprofloxacin, and sparfloxacin against 380 clinical isolates collected from general hospitals in 1996. LB 20304a was the most active agent against gram-positive strains including staphylococci, streptococci and enterococci. LB20304a was also very active against gram-negative bacteria and its activity was comparable to that of ciprofloxacin but better than those of grepafloxacin, Q-35 and sparfloxacin. The therapeutic effect of LB20304a was superior to those of sparfloxacin and ciprofloxacin against systemic infection by methicillin-resistant Staphylococcus aureus K283 (MRSA) in neutropenic mice. Against urinary tract infection induced by Escherichia coli 851E in mice, LB20304a was more active than sparfloxacin and ciprofloxacin. However, LB 20304a was slightly less active than that of ciprofloxacin against urinary tract infection by Pseudomonas aeruginosa 1912E, but better than that of sparfloxacin.

• Journal of Korean Biological Nursing Science
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• v.9 no.1
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• pp.33-48
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• 2007

목적 : 본 연구에서는 한국인 소아의 침 및 성인의 질부로부터 분리한 1367개의 유산 생성 균주 중 4가지의 장내 병원성 세균;Methicillin-resistant Staphylococcus aureus(MRSA), Listeria monocytogenes, Salmonella typhimurium, Escherichia coli O157에 대해 발육억제 효과를 나타내는 유산 균주를 분리하고 분리된 균주의 Probiotic으로서의 가능성을 조사하고자 하였다. 방법 : 네 가지 병원성 세균을 대상으로 agar spot test와 Catalse test를 시행하여 1367개 균주 중 최종적인 실험대상 균주를 선정하였다. 최종 선정된 유산균과 네 가지 병원성 세균을 혼합 배양하여 병원성 세균증식 억제 효과를 보았다. 또한 최종균주의 probiotic으로서의 가능성을 확인하기 위해 균을 동정하고 내산성 등 몇 가지 특성을 관찰하였다. 결과 : Agar spot test 결과 전체의 15.7%에 해당하는 215 균주가 MRSA에 대해 억제 효과를 나타내었으며 215 균주 중 9.8%에 해당하는 21 균주가 L. monocytogenes에도 동시에 억제효과를 나타냈다. 이들 균주 중 가장 탁월한 효과를 보인 Lb 1250을 실험 대상 균주로 선정하였다. Lb(Lactobacillus) 1250과 상술한 병원성 세균을 각각 혼합 배양하면 Lb 1250 존재 하에서 MRSA의 증식은 $10^4$배 억제되었으며, L. monocytogenes는 $10^3$배의 억제 효과를 보였다. 그러나 S. typhimurium, E. coli O157에 대해서는 아주 미약한 효과를 나타냈다. Lb 1250의 몇 가지 특성을 조사한 결과 Lactobacillus delbrueckii subsp. delbrueckii로 동정되었으며, 이는 $H_{2}O_2$를 잘 생산해 내는 균주이었다. 또한 이 균주는 우유에서 curd를 약하게 생성하며 이 curd의 향은 달콤하고 최종 pH가 4.6까지 감소하였으며, pH 2와 같은 강산의 조건하에서 배양한 결과 2시간 후에도 상당한 생존도를 유지하였다. 결론 : 이상의 결과에서 Lb 1250은 병원성 세균의 성장을 억제함을 관찰하였고, probiotic으로서의 이용가능성을 확인하였다.

• Pediatric Infection and Vaccine
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• v.14 no.1
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• pp.83-90
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• 2007

Purpose : Staphylococcal scalded skin syndrome (4S) is a well known disease defined by clinical, microbiological and histological criteria caused by Staphylococcus aureus. This disease is uncommon but has been increasingly recognized. We investigated the clinical features of staphylococcal scalded skin syndrome. Methods : We reviewed retrospectively medical records of 53 patients diagnosis of staphylococcal scalded skin syndrome who were admitted to Changwon Fatima hospital from February 2002 to December 2005. These patients were divided into 3 clinical types; generalized type, intermediate type, abortive type. Age, sex ratio, clinical manifestations, laboratory findings, response to therapy and prognosis were investigated. Result : 1)The mean age of patients was 2.8 years, ranging from 20 days to 7 years. Male-to-female ratio was 1.9:1. 2) By clinical types, 6 patients were in the generalized type (11%), 29 patients in the intermediate type (55%), 18 patients in the abortive type (34%). The coexisting diseases were variable, including conjunctivitis (25 cases), atopic dermatitis (11 cases), otitis media (1 case). On laboratory findings, most of patients didn't have leukocytosis or increased C-reactive protein. 4) A total of fifteen Methicillin Resistant Staphylococcal Aureus (MRSA) strains were isolated from September 2003 through December 2005. Fourteen strains were positive for exfoliative toxin B gene by PCR and negative for enterotoxin, toxic shock syndrome toxin and Panton-Valentine leukocidin genes. 5) The mean duration of admission was 7.3 days. Patients were treated with vancomycin or amoxacillin/clavulanate or ampicillin/sulbactam or cefuroxime without significant sequelaes. Conclusion : Recently, Staphylococcal scalded skin syndrome caused by exfoliative toxin B produced by MRSA in the Changwon area has been increasing.

• Journal of Chest Surgery
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• v.39 no.2 s.259
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• pp.134-139
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• 2006

Background: Complications after surgery for esophageal cancer are various and not rare. Among them, pulmonary complication is well known as one of the most important insults which has negative influence on the postoperative course and results in mortality. So we attempted to analyze the factors which may have relation to postoperative pulmonary complication. Material and Method: The retrospective study was undertaken in 87 patients who underwent curative surgery for esophageal cancer from Jan. 1996 to Aug. 2005. We divided them into two groups, patients with pulmonary complication (group A, n=28), without pulmonary complication (group B, n=59). Statistical analysis was performed with Fisher's exact test. Result: The postoperative pulmonary complication developed in 28 patients ($32\%$). There was no difference between two groups in past medical history, preoperative pulmonary function, surgery time, anastomosis method, pathologic stage, and trial of neoadjuvant therapy. Age and incidence of cervical anastomosis were significantly higher in group A (p=0.001, p=0.023). The rate of routine postoperative ventilator care was significantly higher in group S (p=0.007). Chest tube indwelling time and hospital stay were significantly longer in group A (p=0.011, p=0.001). There were 6 postoperative deaths ($6.8\%$) and 5 deaths were related to pulmonary complication. Pneumonia was the most common cause of death and MRSA (methicillin resistant staphylococcus aureus) was the most common organism in sputum culture. Conclusion: Pulmonary complication after esophageal cancer surgery was the most important cause of death. Pulmonary complication was closely related to patient's age and cervical anastomosis. We think postoperative routine ventilator care is helpful for prevention of pulmonary complications, especially MRSA pneumonia, and reducing mortality.

• Korean Journal of Microbiology
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• v.49 no.3
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• pp.245-252
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• 2013

Pseudomonas aeruginosa and Acinetobacter baumannii are significant opportunistic pathogens in hospitals and are resistant to most antibiotics. Multidrug-resistant P. aeruginosa (MDRPA) and A. baumannii (MDRAB) cause severe human nosocomial infections and are more difficult to treat than methicillin-resistant Staphylococcus aureus (MRSA). Bifidobacteria are among of the most beneficial probiotics and have been widely studied for their antimicrobial activities. The present study explored the antimicrobial activity of Bifidobacterium sp. isolated from healthy Koreans against MDRPA and MDRAB. The antimicrobial activity of the isolates against MDRPA and MDRAB, which are resistant to ciprofloxacin, tobramycin, gentamicin, meropenem, and ceftazidime, was determined by modified broth microdilution methods using absorbance. Among all tested bifidobacteria isolates (nine B. adolescentis, three B. longum, and two B. pseudocatenulatum), the culture supernatant of B. pseudocatenulatum SPM1309 showed a strong growth inhibitory effect against MDRPA and MDRAB. No change in the turbidity of the mixture was observed during incubation, and its inhibitory effect occurred through bacteriostastic action. Moreover, the antibacterial activity was observed in the fraction with molecular weights <10 kDa of bifidobacteria culture supernatant, and the active fraction was heat-stable because it maintained its activity when heated at $70^{\circ}C$ for 10 min. The results suggest that this Bifidobacterium strain could have potential applications for alternative therapy in MDRPA and MDRAB infections.

• Archives of Pharmacal Research
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• v.19 no.1
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• pp.46-51
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• 1996

The in vitro activity of LB 10517, a new catechol-substituted cephalosporin, was compared with those of E-1077, cefpirome and ceftazidime 1034 clinical isolates collected in Japan. LB10517 showed a broad-spectrum antibacterial activity against a wide range of grampositive and gram-negative bacteria including non-glucose fermenting rods, Pseudomonas aeruginosa. Against the methicillin-susceptible strains of Staphylococcus aureus (MSSA) and Strptoccus pyogenes, the $MIC_{90}$ values of LB10517 which required to inhibit 90% of the strains wre $3.13\mug/ml\; and\; 0.1\mug/ml$, respectively. It was as active as E-1077 but more active than cefpirome and ceftazidime. Methicillin-resistant strains of S.aureus (MRSA) and Enterococcus spp. were highly resistant to all the test compunds. LB10517 was highly active against most members of the family Enterobacteriaceae, 90% of which were inhibited at a concentration of less than $0.78\mug/ml$, except for Enterobacter cloacae ($1.56\mug/ml$) and Serratia marcescens ($3.13\mug/ml$)Its activity was comparable to those of E-1077 and cefpirome but it was greater than that of ceftazidime. Against Pseudomonas aeruginosa, LB10517 showed the most potent antibacterial activity among the compounds tested. Ninety percent of P. aeruginosa isolates were susceptible at the concentration of $0.39\mug/ml$. Its activity was 32-to 128 fold higher than those of E-1077, cefpirome and ceftazidime. Against imipenem- or ofloxacin-resistant P. aeruginosa, LB10517 with $MIC_{90}\; of\; 6.25 \\mug/ml\; and\; 3.13\mug/ml$, respectively, showed 16-fold more potent activity than the other test compounds. LB10517 showed a relatively high plasma level and long plasma elimination half-life in rats $(t_{1/2}(\beta,\; 52 min)\; and\; dogs\; (t_{1/2}(\beta),\; 103 min)$.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.14
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• pp.5787-5791
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• 2014

Background: With increasing survival periods and diversification of treatment methods, treatment of critically ill cancer patients has become an important factor influencing patient prognosis. Patients with cancer are at high risk of infections and subsequent complications. This study investigated the incidence and factors contributing to the development of ventilator-associated pneumonia (VAP). Materials and Methods: This retrospective study investigated the incidence of VAP and factors leading to infection in patients admitted to the intensive care unit (ICU) of a cancer center from January 1, 2012 to December 31, 2013. Results: The incidence of VAP was 2.13 cases per 1,000 days of intubation, and 13 of 288 patients (4.5%) developed VAP. Lung cancer was the most common cancer associated with VAP (N=7, 53.9%), and longer hospital stays and intubation were associated with increased VAP incidence. In the group using a "ventilator bundle," the incidence was 1.14 cases per 1,000 days compared to 2.89 cases per 1,000 days without its use; however, this difference was not statistically significant (p=0.158). Age (${\geq}65$, OR=5.56, 95% confidence interval [CI]=1.29-23.95), surgery (OR=3.78, 95%CI=1.05-13.78), and tracheotomy (OR=4.46, 95%CI=1.00-19.85) were significant VAP risk factors. The most common causative organisms were methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa (N=4, 30.8% each), followed by Acinetobacter baumannii and Candida albicans (N=2, 15.4% each). Conclusions: The incidence of pneumonia among critically ill cancer patients is highest in those with lung cancer, but lower than among non-cancer patients. The length of hospital stay and time on mechanical ventilation are important risk factors for development of VAP. Although not statistically significant, "ventilator bundle" care is an effective intervention that delays or reduces incidence of VAP. Major risk factors for VAP include age (${\geq}65$ years), surgery, and tracheostomy, while fungi, gram-negative bacteria, and multidrug-resistant organisms were identified as the major causative pathogens of VAP in this study.