• Microbiology and Biotechnology Letters
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• 제17권6호
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• pp.634-644
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• 1989

Listeria monocytogenes, one of five species in the genus Listeria and the only one currently believed to be pathogenic for humans, is a small gram-positive, nonsporeforming, aerobic, motile and hemolytic rod-shaped bacterium. The bacterium is widespread in the environment, having been isolated from soil, dust, animal feed, water, sewage, almost every type of animal that has been cultured, and asymptomatic humans. L. monocytogenes causes listeriosis, a disease which most often affects humans with a compromised immune system. Included are pregnant woman, infants and adults suffering from such diseases as cancer, cirrhosis of liver or AIDS or are being treated with drugs such as corticosteroids. Listeriosis is manifested by such syndromes as pregnancy infections, granulomatosis infantiseptica, sepsis, meningoencephalitis, and focal infections. Infections, can be treated successfully with penicillin, ampicillin, or erythromycin. However, a mortality rate of about 30％ has occurred in outbreaks of listeriosis. Food-associated outbreaks of listeriosis have been attributed to coleslaw (Canada, 1981), pasteurized milk (U.S., 1983), and soft cheese (U.S., 1985). Presence of L. monocytogenes in various dairy foods has prompted recall of such products from the U.S. market-place. L. monocytogenes also has been found in raw meats and seafood.

• YAKHAK HOEJI
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• 제40권1호
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• pp.95-101
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• 1996

The in vitro antibacterial activities of LB10522, a new catechol-substituted cephalosporin, were compared with those of cefpirome, ceftazidime, ceftriaxone, and cefoperaz one against clinical isolates and laboratory standard anaerobes. LB10522 had broad spectrum antibacterial activities against both gram-positive and gram-negative microorganisms. It was most active against gram-positve bacteria among the reference cephalosporins tested. Against gram-negative strains such as the family Enterobacteriaceae, LB10522 showed an activity comparable to that of cefpirome. But LB10522 was more potent than ceftazidime, ceftriaxone and cefoperazone. In particular, Pseudomonas aeruginosa was highly susceptible to LB10522, which was 32-fold and 64-fold more active than ceftazidime and cefpirome, respectively. Against anaerobic strains, the activity of LB10522 was similar to those of reference compounds. LB10522 exhibited potent therapeutic activities against experimental local infections in mice. The therapeutic effect of LB10522 against urinary tract infection (UTI) caused by P. aeruginosa 1912E in mice was superior to that of cefpirome. Against experimental respiratory tract infection (RTI) caused by K. pneumoniae DT-S in mice, LB10522 was as effective as cefpirome. The in vivo efficacy of LB10522 was correlated well with its in vitro activity.

• Clinical and Experimental Pediatrics
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• 제62권1호
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• pp.36-41
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• 2019

Purpose: In this study, we investigated the clinical features and prognostic factors of early-onset sepsis (EOS) in neonatal intensive care unit (NICU) patients. Methods: A retrospective analysis was conducted on medical records from January 2010 to June 2017 (7.5 years) of a university hospital NICU. Results: There were 45 cases of EOS (1.2%) in 3,862 infants. The most common pathogen responsible for EOS was group B Streptococcus (GBS), implicated in 10 cases (22.2%), followed by Escherichia coli, implicated in 9 cases (20%). The frequency of gram-positive sepsis was higher in term than in preterm infants, whereas the rate of gram-negative infection was higher in preterm than in term infants (P<0.05). The overall mortality was 37.8% (17 of 45), and 47% of deaths occurred within the first 3 days of infection. There were significant differences in terms of gestational age (26.8 weeks vs. 35.1 weeks) and birth weight (957 g vs. 2,520 g) between the death and survival groups. After adjustments based on the difference in gestational age and birth weight between the 2 groups, gram-negative pathogens (odds ratio [OR], 42; 95% confidence interval [CI], 1.4-1,281.8) and some clinical findings, such as neutropenia (OR, 46; 95% CI, 1.3-1,628.7) and decreased activity (OR, 34; 95% CI, 1.8-633.4), were found to be associated with fatality. Conclusion: The common pathogens found to be responsible for EOS in NICU patients are GBS and E. coli. Gram-negative bacterial infections, decreased activity in the early phase of infection, and neutropenia were associated with poor outcomes.

• Journal of Microbiology and Biotechnology
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• 제27권1호
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• pp.19-25
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• 2017

Staphylococcus aureus (S. aureus) is a common gram-positive bacterium that causes serious infections in humans and animals. With the continuous emergence of methicillin-resistant S. aureus (MRSA) strains, antibiotics have limited efficacy in treating MRSA infections. Accordingly, novel agents that act on new targets are desperately needed to combat these infections. S. aureus alpha-hemolysin plays an indispensable role in its pathogenicity. In this study, we demonstrate that sclareol, a fragrant chemical compound found in clary sage, can prominently decrease alpha-hemolysin secretion in S. aureus strain USA300 at sub-inhibitory concentrations. Hemolysis assays, western-blotting, and RT-PCR were used to detect the production of alpha-hemolysin in the culture supernatant. When USA300 was co-cultured with A549 epithelial cells, sclareol could protect the A549 cells at a final concentration of $8{\mu}g/ml$. The protective capability of sclareol against the USA300-mediated injury of A549 cells was further shown by cytotoxicity assays and live/dead analysis. In conclusion, sclareol was shown to inhibit the production of S. aureus alpha-hemolysin. Sclareol has potential for development as a new agent to treat S. aureus infections.

• Natural Product Sciences
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• 제4권1호
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• pp.32-37
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• 1998

The water extracts of oriental herbal medicines which have been clinically used to treat bacterial infections in Korea were screened for in vitro antibacterial activity by the paper disc assay method. Two Gram positive bacteria, Staphylococcus aureus SG511, Bacillus subtilis ATCC 6633 and two Gram negative bacteria, Escherichia coli 055, Pseudomonas aeruginosa 9027 were used as test organisms. Among 83 of the extracts tested, 25 were active against Staphylococcus aureus SG511, 9 were active against Bacillus subtilis ATCC 6633, while none showed inhibitory activity against Eschelichia coli 055 and Pseudomonas aeruginosa 9027. Among them, Hwangyonhaedoktang plus hwangyon, Chongwisan, and Ssangbaksan showed remarkably potent antibacterial activity.

• The Korean Journal of Food & Health Convergence
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• 제9권6호
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• pp.9-19
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• 2023

Lactobacillus plantarum and Leuconostoc mesenteroides are crucial functional starters and predominant isolates in a wide range of fermented foods, particularly kimchi, whose constituents exhibit bioactive properties. We previously developed a methodology using anion exchange resins to purify peptidyl compounds from Lb. plantarum LBP-K10. Antibacterial cultures of Lb. plantarum LBP-K10 were obtained from the respective cultures' supernatants and filtrates. However, conclusive evidence of the efficacy of kimchi filtrates in eradicating pathogenic bacteria is lacking. We aimed to simulate the potential effects of antibacterial filtrates that contained antibacterial compounds which were derived from cultures of Lb. plantarum LBP-K10. We acquired the kimchi filtrates using a combination of centrifugation and filtration methodologies, without the requirement for inoculation. The filtered liquid from Chinese cabbage kimchi, inoculated with Lb. plantarum LBP-K10 as a starter culture, and the non-inoculated liquid from Chinese cabbage kimchi (referred to as CCK and CCKRef, respectively) were were examined. CCK demonstrated greater inhibitory activity and a more significant bactericidal effect against the bacterial indicator strains. The minimum inhibitory concentration demonstrated comparable outcomes in tests against both Gram-positive and Gram-negative bacteria. This research offers a groundbreaking examination that displays the effectiveness of profiling peptidyl compounds within kimchi filtrates for curing bacterial infections.

• Neonatal Medicine
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• 제16권1호
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• pp.94-98
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• 2009

Listeria monocytogenes (L. monocytogenes) is a foodborne anaerobic gram-positive rod and the third most common pathogen for neonatal meningitis. Although the mortality and morbidity of L. monocytogenes infections are high, thus causing serious problems in Western populations, neonatal listeriosis is relatively rare in Eastern countries, including Korea. Possible routes for intrauterine infection or vertical transmission of L. monocytogenes include infected placentas and the reproductive tract. Intrauterine infections may cause chorioamnionitis, preterm labor, spontaneous abortion, stillbirth, or neonatal infection. A high index of suspicion and early empirical antibiotic treatment are critical to achieve a favorable prognosis for neonatal listeriosis. We managed a case of L. monocytogenes sepsis and pneumonia in a premature neonate born at 26 weeks of gestational age from an asymptomatic mother with culture-proven placental infection. The neonate was successively treated with ampicillin and gentamicin.

• Korean Journal of Veterinary Research
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• 제47권1호
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• pp.43-50
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• 2007

Staphylococci are Gram-positive, facultatively anaerobic cocci, normally found on the skin andmucosal surfaces of most warm-blooded animals and often involved in a wide variety of diseases in animals.Staphylococcal infections are treated with antibiotics and, consequently, antibiotic resistance and/or acquiredresistance have developed. Staphylococcus (S.) intermedius and Staphylococcus (S.) aureus are 2 comonveterinary isolates that are frequently associated with suppurative infections. This study was undertaken toexamine antimicrobial susceptibility of S. aureus (23 isolates) and S. intermedius (160 isolates) isolatedfrom dogs in Gwangju, Korea and investigate whether the antibiotic resistance of S. aureus and S.intermedius is efected by the site of isolation, age, and sex of dogs. More isolates were isolated fromadult dogs (71.3%) than juveniles (20.5%). Antimicrobial resistance was commonly found for Penicillin,Tetracycline, Trimethoprim-Sulphamethoxazole in both Staphylococcus species. All of the isolates weresusceptible to Amoxicillin/Clavulanic Acid, Cephalothin, Oxacilin, Neomycin, and Vancomycin. Appropriateprotocol for antibiotic use and strategies to reduce antimicrobial resistance rate will be needed. Periodicsubstitution of antimicrobial agents and limitation of antibiotic use should also be considered.

• Archives of Plastic Surgery
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• 제42권1호
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• pp.68-72
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• 2015

For recent years, use of autologous fat injection has increased significantly in facial contouring surgery. Along with such increase in use, complications like atypical mycoplasma infection have been also on the increasing trend. The authors report two cases of Mycobacterium chelonae infection that occurred after autologous fat injection. Patients were treated as infection that resistant to common antibiotics and results were negative to routine culture and Gram staining. Acid-fast bacillus stain, polymerase chain reaction (PCR) test and mycobacterial cultures were conducted for diagnosis under suspicion of atypical mycoplasma infection. Then, combination antibiotics therapy, surgical treatment, and steroid injection were performed for treatment. Both patients were diagnosed with Mycobacterium chelonae in PCR test. They were positive to mycobacterial cultures. Combination antibiotics therapy was repeated to improvement of symptom. However, they could not be free from side effects such as deformation in facial contour, scar and pigmentation even after full recovery. When chronic wound infections after autologous fat injection, we must suspect atypical or mycobacterial infection and conduct examinations for a early diagnosis and proper antibiotic therapy that is effective to the nontuberculous mycobacteria.

• Clinical and Experimental Pediatrics
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• 제50권7호
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• pp.643-648
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• 2007

Purpose : Sepsis is a common complication in Neonatal Intensive Care Units (NICU), seen especially in low birth weight (LBW) infants. A recent study showed that fungal or gram-negative sepsis is associated with a greater degree of thrombocytopenia than is seen with gram-positive sepsis. So, this study was undertaken to examine the platelet counts and platelet indices in LBW infants during episodes of sepsis. Methods : We analyzed 36 cases with culture-proven sepsis on chart review in LBW infants admitted to the NICU at Wonkwang University Hospital from January 2001 to June 2006. Results : Patients were grouped by organism type: gram-positive bacteria ($1,521{\pm}309g$, $31.3{\pm}2.9wk$, 15/36), gram-negative bacteria ($1,467{\pm}290g,\;30.6{\pm}3.6wk$, 17/36), and fungi ($1,287{\pm}205g,\;30.0{\pm}3.9wk$, 4/36). The most common organism was Staphylococcus epidermis and the incidence of thrombocytopenia was 88.9%. When compared with infants with gram-positive sepsis, those with gram-negative sepsis had significantly higher incidences of thrombocytopenia, lower initial platelet count, lower platelet nadir, and greater mean percentage decrease in platelet count from before the onset of sepsis. Those with fungal infections were similar to gram-negative sepsis, but they were not significant because of the small number of patients. And mean platelet volume (MPV) in sepsis was increased more significantly in time of platelet nadir than before the onset of sepsis. Conclusion : We conclude that decrease in platelet count was significantly greater in gram-negative sepsis than gram-positive sepsis, and also greater than fungal sepsis-which was insignificant because of the small number of patients-in LBW infants. And elevation in MPV will be helpful in the diagnosis and treatment of sepsis in LBW infants.