• Natural Product Sciences
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• v.13 no.4
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• pp.342-346
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• 2007

The antimicrobial activity of the essential oil from Pelargonium graveolens and its effects when it was combined with current antibiotics against antibiotic-resistant strains of Streptococcus pneumoniae were evaluated. The minimal inhibitory concentrations (MICs) of the essential oil fraction and the main components of this plant were determined for two antibiotic-susceptible and two antibiotic-resistant strains of S. pneumoniae using broth microdilution tests. The combined effects of the oil with erythromycin, norfloxacin, or oxacillin were evaluated using a checkerboard microtitre assay. The combination of the oil fraction of P. graveolens, or its main component, together with the antibiotics tested significantly lowered the MICs of the antibiotics against all of the tested strains with fraction inhibiting concentration indices (FICs) ranging from 0.16 to 1.50. In particular, the activity of norfloxacin against all of the tested strains of S. pneumoniae was enhanced significantly by combination with citronellol. In conclusion, the combination of P. graveolens oil with antibiotics could be used to reduce the effective dose of antibiotic and to modulate the resistance of S. pneumoniae strains.

• The Journal of Korean Medicine
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• v.26 no.3 s.63
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• pp.98-109
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• 2005

Objectives : This study was designed to identify the effects of Salvia Miltiorrhiza or antibacterial activity against Streptococcus pneumoniae ATCC 33400. Methods : The ethanol- and water-extracts of more than 80 oriental herbal medicines were investigated by the Kirby-Bauer method to determine their inhibitory effect on growth of S. pneumoniae ATCC 33400 in vitro. Of thorn, Salvia Miltiorrhiza was selected. Results : The ethanol-soluble extract of Salvia Miltiorrhiza showed relatively high antibacterial activity against S. pneumoniae ATCC 33400. However, the water-soluble extract of Salvia Miltionrhiza showed no antibacterial activity. The ethanolic extract was forker fractionated with organic solvents such as hexane, chloroform, and ethyl acetate in that order. Among the fraction tested, the chloroform fraction showed the highest antibacterial activity, when the ethanol-soluble extract of Salvia Miltiorrhiza minimal inhibitory concentration (MIC) was 25${\mu}g/ml$. Conclusions : Further study should be carried out to identity of the cell growth inhibition effects of S. pneumoniae ATCC 33400.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.70.2-71
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• 2003

Quinolone resistance in Streptococcus pneumoniae is related to mutations in the DNA gyrase and topoisomerase IV genes. DW-286a displayed potent activity against S. pneumoniae C9211 (MIC, 0.015 ${\mu}$g/ml) compared with gemifloxacin (MIC, 0.06 ${\mu}$g/ml). This study was performed to analyze the ability of DW-286a to cause resistance development in S. pneumoniae and to establish whether DNA gyrase or topoisomerase IV is primary target. DW-286a resistant mutants of S. pneumoniae C9211 were generated by stepwise selection at increasing drug concentration. (omitted)

• Clinical and Experimental Pediatrics
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• v.60 no.5
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• pp.151-157
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• 2017

Purpose: Macrolide resistance rate of Mycoplasma pneumoniae has rapidly increased in children. Studies on the clinical features between macrolide susceptible-M. pneumoniae (MSMP) and macrolide resistant-M. pneumoniae (MRMP) are lacking. The aim of this study was to identify the macrolide resistance rate of M. pneumoniae in Korean children with M. pneumoniae penupmonia in 2015 and compare manifestations between MSMP and MRMP. Methods: Among 122 children (0-18 years old) diagnosed with M. pneumoniae pneumonia, 95 children with the results of macrolide sensitivity test were included in this study. Clinical manifestations were acquired using retrospective medical records. Results: The macrolide resistant rate of M. pneumoniae was 87.2% (82 of 94 patients) in children with M. pneumoniae pneumonia. One patient showed a mixed type of wild type and A2063G mutation in 23S rRNA of M. pneumoniae. There were no significant differences in clinical, laboratory, and radiologic findings between the MSMP and MRMP groups at the first visit to our hospital. The time interval between initiation of macrolide and defervescence was significantly longer in the MRMP group ($4.9{\pm}3.3$ vs. $2.8{\pm}3.1days$, P=0.039). Conclusion: The macrolide resistant rate of M. pneumoniae is very high in children with M. pneumoniae pneumonia in Korea. The clinical manifestations of MRMP are similar to MSMP except for the defervescence period after administration of macrolide. Continuous monitoring of the occurrence and antimicrobial susceptibility of MRMP is required to control its spread and establish strategies for treating second-line antibiotic resistant M. pneumoniae infection.

• Clinical and Experimental Pediatrics
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• v.52 no.12
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• pp.1358-1363
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• 2009

Purpose:The aim of this study was to determine the prevalence of asymptomatic nasopharyngeal carriages in children using a multiplex reverse transcriptase-polymerase chain reaction (mRT-PCR) assay kit. Methods:We obtained nasopharyngeal swabs from 33 children without any underlying disease from July 25 to July 28, 2008. The children were free from the signs of respiratory tract infections at the time of sampling. DNA was extracted from the swabs and subjected to multiplex RT-PCR using a primer set for the detection of pneumococci ($Seeplex^{(R)}$ PneumoBacter ACE Detection Seegene, Seoul, Korea). The amplified PCR products were separated on 2% agarose gels and stained with either ethidium bromide or screen tape system (Lab901 Scotland, UK). Results:A total of 33 children (male, 15 female, 18) aged between 3.2 and 16.3 (median, 8.2) years were included in this study. The mRT-PCR detected colonized bacteria (Streptococcus pneumoniae, Hemophilus influenzae, Chlamydia pneumoniae, and Bordetella pertussis) in 30 children (90.9%). Of these, 13 children (39.4%) showed more than 2 bacteria: 12 children were positive for 2 bacteria (S. pneumoniae and H. influenzae) and 1 child was positive for 3 bacteria (S. pneumoniae, H. influenzae, and C. pneumoniae). Conclusion:mRT-PCR was found to be a sensitive tool for the detection of asymptomatic nasopharyngeal carriages. Clinical significances of the bacteria detected by mRT-PCR will have to be evaluated in the future.

• Biomolecules & Therapeutics
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• v.18 no.3
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• pp.271-279
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• 2010

Streptococcus pneumoniae is the major pathogen that frequently causes serious infections in children, the elderly and immunocompromised patients. S. pneumoniae is known to produce reactive oxygen species (ROS) and S. pneumoniae-produced ROS is considered to play a role in pneumococci pathogenesis. SIGN-R1 is the principal receptor of capsular polysaccharides (CPSs) of S. pneumoniae. However, there is a considerable lack of knowledge about the protective role of SIGN-R1 against S. pneumoniae-produced ROS in SIGN-$R1^+$ macrophages. While investigating the protective role of SIGN-R1 against ROS, we found that SIGN-R1 intimately bound to peroxiredoxin-1 (Prx-1), one of small antioxidant proteins in vitro and in vivo. This interaction was increased with ROS generation which was produced by stimulating SIGN-R1 with dextran, a polysaccharide ligand of SIGN-R1. Also, SIGN-R1 crosslinking with 22D1 anti-SIGN-R1 antibody increased Prx-1 in vitro or in vivo. These results suggested that SIGN-R1 stimulation with CPSs of S. pneumoniae increase the expression level of Prx-1 through ROS and its subsequent interaction to SIGN-R1, providing an important antioxidant role for the host protection against S. pneumoniae.

• Journal of Life Science
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• v.15 no.6 s.73
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• pp.863-870
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• 2005

One hundred and twenty three strains of Mycoplasma pneumoniae were isolated from patients with respiratory diseases from February 2002 to April 2005 in Busan, Korea. The MICs of tetracycline and erythromycin up to $90\%$ of the 123 M. pneumoniae isolates tested were $0.5\~1.0$, and $0.5\~512{\mu}/ml$, respectively. Plasmid DNA was not isolated from all of the M. pneumoniae isolates. Out of 323 strains of M. pneumoniae, 57 ($46.3\%$) stains contain tetM gene on their chromosomal DNA, and 60 ($48.8\%$) strains were mutated in domain V of 23S rRNA for erythromycin resistance. Out of 63 strains of M. pneumoniae which were not mutated in domain V of 235 rRNA for erythromycin resistance, 36 ($57.1\%$) strains contained tetM gene, and out of 60 strains of M. pneumoniae which were mutated in domain V of 23S rRNA for erythromycin resistance, 21 ($35.0\%$) strains contained tetM gene. These results suggest that the isolation rate of erythromycin and tetracycline resistant M. pneumoniae is higher than those of other countries, and erythromycin and tetracycline are not first choice drug for M. pneumoniae infection in Korea, and it need confirm by a nationwide surveilance of antimicrobial resistance.

• Journal of Environmental Health Sciences
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• v.30 no.1
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• pp.15-21
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• 2004

In an attempt to analyze the characteristics of domestic pathogenic strains of S. pneumoniae, the basic epidemiological charactristics of pathogenic strains such as their serotypes and frequency of penicillin resistance, and pattern of chromosomal DNA from PFGE(pulsed-field gel electrophoresis) were observed. For this study,56 strains of S. pneumoniae isolated from inpatients and outpatients in the four domestic university hospitals were collected from January to December in 1998. Among those strains, a total of 56 pathogenic strains from blood(39 isolates), cerebrospinal fluid(8 isolates) and other specimen(9 isolates) were selected and isolated. The penicillin resistance frequency of those 56 strains was identified with disk diffusion method with 66.1％. From the invasive strains, predominant serotypes were isolated in the order of 19F(12.5％), 23F(10.7%), 14(10.7%) and 9V(10.7％), totalling 45 percent. This experiment also used PFGE patterns to compare the correlations among genetic subtypes in several serotypes. The DNA fragments digested with Sma I and Apa I were resolved by PFGE. The PFGE patterns digested with Sma I were better than Apa I for analysis. In the DNA fragments digested with Sma 1, PFGE analysis of 56 S. pneumoniae isolates showed 25 different patterns. As a result, serotype was on the whole correlated to PFGE pattern on the ground that each different PFGE pattern by serotype was observed. This study can be utilized not only fur the study of incidence trend of domestic pneumococcal diseases but also as a useful basic data for the development of identification tool and treatment.

• Journal of Yeungnam Medical Science
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• v.28 no.1
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• pp.13-19
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• 2011

The emergence of antibiotic-resistant pathogens is a Serious clinical problem in the treatment of infectious diseases that increase mortality, morbidity, hospitalization length, and the cost of healthcare. In particular, $Streptococcus$ $pneumoniae$ is a major etiologic pathogen of pneumonia, sinusitis, otitis media, and meningitis. As the definition of penicillin resistance to $S.$ $pneumoniae$ was recently changed, macrolide-resistant $S.$ $pneumoniae$ is a major resistant pathogen in the community. Infections caused by antibiotic-resistant strains are associated with incorrect use of antibiotics and critical clinical outcomes. For the appropriate use of antibiotics to treat infections, physicians always should have up-to-date information on the current epidemiologic status of antibiotic resistance for common pathogens and their susceptibility to antimicrobials. Appropriate selection of antimicrobials, strict control of infection, vaccination, and development of a feasible national policy of infection control are important strategies for the control of antimicrobial resistance. This review article focuses on the current status of antibiotic-resistant $S.$ $pneumoniae$ in community-acquired pneumonia in Korea.

• Journal of Microbiology
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• v.44 no.4
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• pp.375-382
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• 2006

From its initial colonization to causation of disease, Streptococcus pneumoniae has evolved strategies to cope with a number of stressful in vivo environmental conditions. In order to analyze a global view of this organism's response to heat shock, we established a 2-D electrophoresis proteome map of the S. pneumoniae D39 soluble proteins under in vitro culture conditions and performed the comparative proteome analysis to a 37 to $42^{\circ}C$ temperature up-shift in S. pneumoniae. When the temperature of an exponentially growing S. pneumoniae D39 culture was raised to $42^{\circ}C$, the expression level of 25 proteins showed changes when compared to the control. Among these 25 proteins, 12 were identified by MALDI-TOF and LC-coupled ESI MS/MS. The identified proteins were shown to be involved in the general stress response, energy metabolism, nucleotide biosynthesis pathways, and purine metabolism. These results provide clues for understanding the mechanism of adaptation to heat shock by S. pneumoniae and may facilitate the assessment of a possible role for these proteins in the physiology and pathogenesis of this pathogen.