Three new alkyl substituted anthraquinone derivatives, trivially named as symploquinones A-C (Compounds 1-3) were isolated from Symplocos racemosa. The structures of these compounds were determined on the basis of extensive spectroscopic analyses (UV, IR, Mass, H- and C-NMR, and two-dimensional (2D) NMR techniques). The resulting data were also compared with the reported literature. These compounds were then subjected to antibacterial or antibiofilm testing. Compounds 1 and 3 exhibited good antibacterial activity in the concentration range of 160-83 μg·mL against Streptococcus mutans, methicillin resistant Staphylococcus aureus and Proteus mirabilis. Both compounds were further screened for anti-biofilm activity, which revealed promising activities at sub-MIC concentrations. None of the compounds were found to be active against Klebsiella pneumoniae.
Anthraquinones ; chemistry ; isolation & purification ; pharmacology ; Anti-Bacterial Agents ; chemistry ; isolation & purification ; pharmacology ; Biofilms ; drug effects ; growth & development ; Ericales ; chemistry ; Magnetic Resonance Spectroscopy ; Mass Spectrometry ; Methicillin-Resistant Staphylococcus aureus ; drug effects ; physiology ; Microbial Sensitivity Tests ; Proteus mirabilis ; drug effects ; physiology ; Spectrophotometry, Infrared ; Streptococcus mutans ; drug effects ; physiology

In Republic of Korea, a 7-valent pneumococcal conjugated vaccine (PCV7) was licensed for use in infants in 2003, and 13-valent PCV (PCV13) replaced it since 2010. We investigated trends in serotype distribution and antibiotic susceptibility of pneumococcal isolates from adult patients with invasive pneumococcal diseases (IPD). Invasive pneumococcal isolates from adult patients of ≥ 16 years of age were collected from 1997 to 2012. Serotypes of the isolates were determined by the Quellung reaction. Distribution of serotypes was analyzed according to the vaccine types. Antibiotic susceptibility was tested by using E-test strips. A total of 272 invasive pneumococcal isolates were included. The most common serotypes were serotype 19F (8.5%, 23/272), and serotype 3 (8.1%, 22/272), and 24.6% (67/272) of the isolates were of non-vaccine serotypes. Of the 272 isolates, 2.6% (7/272) were penicillin MICs of ≥ 4 µg/mL. The proportion of the PCV13 serotypes decreased from 63.3% (50/79) in 1997-2003 to 48.6% (17/35) in 2011-2012, whereas that of non-vaccine serotypes was 26.6% (21/79) and 25.7% (9/35), respectively, for the same periods. The proportion of the PCV13 serotypes showed a decreasing trend among adult patients with IPD over the study period.
Adolescent ; Adult ; Aged ; Anti-Infective Agents/*pharmacology/therapeutic use ; Ceftriaxone/pharmacology/therapeutic use ; Female ; Humans ; Male ; Microbial Sensitivity Tests ; Middle Aged ; Penicillins/pharmacology/therapeutic use ; Pneumococcal Infections/drug therapy/*microbiology/mortality ; Republic of Korea ; Serogroup ; Serotyping ; Streptococcus pneumoniae/*drug effects/isolation & purification ; Young Adult

BACKGROUND: We determined the epidemiological characteristics of erythromycin (EM)-resistant Streptococcus pyogenes (group A streptococci, GAS) strains isolated from Korea and Japan, using emm genotyping and multilocus sequence typing (MLST). METHODS: Clinical isolates of GAS had been collected from 1992 to 2012 in Korea and from 2004 to 2009 in Japan. EM resistance was determined by the microdilution method, and resistance genotypes were assessed by PCR. The emm genotyping and MLST were performed by DNA sequencing. RESULTS: The emm genotypes and sequence types (STs) were concordant in 143 (85.1%) of 168 EM-resistant GAS strains from Korea. ST36/emm12 (35.1%), ST52/emm28 (22.6%), and ST49/emm75 (16.1%) were the most common types. Most of the ST36 (93.9%) and ST52 (95.8%) strains harbored erm(B), whereas strains ST49, ST42, and ST15 contained mef(A). The concordance between emm genotypes and STs was 41 (93.2%) among 44 EM-resistant GAS strains from Japan. ST36/emm12 (34.1%), ST49/emm75 (18.2%), and ST28/emm1 (15.9%) were the major types. ST36 isolates harbored either erm(B) (56.3%) or mef(A) (37.5%), whereas isolates ST28, ST49, and ST38 carried only mef(A). The proportion of erm(B) and mef(A) was 66.1% and 33.3% in Korea and 22.7% and 68.2% in Japan, respectively. CONCLUSIONS: The common STs in Korea and Japan were ST36 and ST49, whereas ST52 was present only in Korea and ST28 only in Japan. Genotype erm(B) was predominant in Korea, whereas mef(A) was frequent in Japan. There were differences between Korea and Japan regarding the frequencies of emm genotypes, STs, and EM resistance genes among the EM-resistant GAS.
Anti-Bacterial Agents/*pharmacology/therapeutic use ; Bacterial Proteins/*genetics ; Bacterial Typing Techniques ; *Drug Resistance, Bacterial ; Epidemiologic Studies ; Erythromycin/*pharmacology/therapeutic use ; Genotype ; Humans ; Japan/epidemiology ; Microbial Sensitivity Tests ; Multilocus Sequence Typing ; Republic of Korea/epidemiology ; Streptococcal Infections/drug therapy/*microbiology ; Streptococcus pyogenes/drug effects/*genetics/isolation & purification

BACKGROUND: The present analysis focuses on phenotypic and genotypic characterizations of efflux-mediated erythromycin resistance in Streptococcus pneumoniae due to an increase in macrolide resistance in S. pneumoniae worldwide. METHODS: We investigated the prevalence of efflux-mediated erythromycin resistance and its relevant genetic elements from 186 specimens of S. pneumonia isolated from clinical and normal flora from Tehran, Iran. The presence of erythromycin resistance genes was tested by PCR with two sets of primers, specific for erm(B) and mef(A/E), and their genetic elements with tetM, xis, and int genes. Isolates were typed with the BOX PCR method and tested for resistance to six antibiotics. RESULTS: Antibiotic susceptibility tests revealed that 100% and 47% isolates were resistant to tetracycline and erythromycin, respectively. The erythromycin and clindamycin double-disc diffusion test for macrolide-lincosamide-streptograminB (MLSB) resistance phenotype showed 74 (84%) isolates with the constitutive MLSB phenotype and the remaining with the M phenotype. BOX PCR demonstrated the presence of 7 types in pneumococci with the M phenotype. Fourteen (16%) isolates with the M phenotype harbored mef(A/E), tetM, xis, and int genes. CONCLUSIONS: The present results suggest dissemination of polyclonal groups of S. pneumoniae with the M phenotype carrying resistance genes attributed to transposon 2009.
Anti-Bacterial Agents/*pharmacology ; Bacterial Proteins/genetics ; DNA, Bacterial/metabolism ; Drug Resistance, Multiple, Bacterial/*genetics ; Erythromycin/*pharmacology ; Genotype ; Humans ; Microbial Sensitivity Tests ; Phenotype ; Pneumococcal Infections/microbiology/pathology ; Polymerase Chain Reaction ; Streptococcus pneumoniae/*drug effects/*genetics/isolation & purification ; Tetracycline/pharmacology

OBJECTIVEGroup A β-hemolytic streptococcus (GAS) or Streptococcus pyogenes may be encountered in diverse clinical situations in children. A rising incidence of invasive group A streptococcus (IGAS) infections has been noted in children in the past three decades. The aim of this study was to summarize the clinical characteristics and antimicrobial resistance of IGAS in children, and to raise the level of diagnosis and treatment of this infection.

METHODThe clinical data from 19 cases of IGAS younger than 14 years old seen from January 2004 to December 2011 treated in the authors' hospital were analyzed. IGAS infections are defined as the isolation of GAS from a normally sterile site in patients.

RESULTThe 19 cases were identified as IGAS infections, among whom 15 were male and 4 were female, and the ratio of them was 3.75. The age ranged from 1 day to 14 years, with a median age of 4 years. The course of disease was 4 h-10 days. The average length of stay was 12.2 days. In 13 cases the episodes of the infection occurred in winter and spring. In 18 cases the infection was community-acquired. Overall, 10 cases had neck or foot dorsum abscess, four cases had purulent peritonitis, and 3 cases were diagnosed as streptococcal toxic shock syndrome (STSS) complicated with empyema, pyopneumothorax occurred in 1 case and neonatal septicemia in another. Three cases had an underlying disease, including 2 cases wounded in a car accident and 1 case of congenital esophageal atresia and tracheoesophageal fistula. Before the isolation of GAS, 5 cases had stayed in ICUs, the length of ICU stay was 1-32 days, 4 cases had received intubation and mechanical ventilation, the ventilation time was 8 h-24 days, 2 cases had received major surgery; 5 cases had other pathogen coinfection, including 4 cases of abdominal pus at the same time and Escherichia coli was isolated, and 1 case had parainfluenza virus type I coinfection. Peripheral blood leucocyte increased in 18 cases, one case dropped off. The C-reactive protein (CRP) levels increased in all patients, including 16 cases who had 14-160 mg/L, 3 cases had levels higher than 160 mg/L. Twenty strains of GAS were isolated from 19 cases' sterile sites, of them 10 strains were isolated from abscess, 4 strains were isolated from blood and another 4 from ascites. Two strains were from the same patient at different times of pleural effusion. All 20 strains displayed a full susceptibility to cefazolin, levofloxacin and vancomycin, and the rates of resistance to both cefotaxime and penicillin were 10.0%. The rates of resistance to erythromycin and clindamycin were 55.0% and 70.0% respectively. Among the patients 3 cases were cured, 14 cases improved, and 2 cases died, of whom 1 case died of STSS secondary to multiple organ dysfunction, 1 case died of basic disease secondary to multiple organ dysfunction.

CONCLUSIONSkin and soft tissues were the most common IGAS infection sites in children, and IGAS infection also can lead to serious STSS and even can be life threatening. Penicillin and cephalosporin are still sensitive for children IGAS infections.

Abscess ; drug therapy ; epidemiology ; microbiology ; Adolescent ; Anti-Bacterial Agents ; pharmacology ; therapeutic use ; Cephalosporins ; therapeutic use ; Child ; Child, Preschool ; Clindamycin ; therapeutic use ; Community-Acquired Infections ; drug therapy ; epidemiology ; microbiology ; Drug Resistance, Bacterial ; Female ; Humans ; Infant ; Infant, Newborn ; Male ; Microbial Sensitivity Tests ; Retrospective Studies ; Soft Tissue Infections ; drug therapy ; epidemiology ; microbiology ; Streptococcal Infections ; drug therapy ; epidemiology ; microbiology ; Streptococcus pyogenes ; drug effects ; isolation & purification

OBJECTIVETo investigate nasopharyngeal carriage rate, antimicrobial resistance and serotype distribution of Streptococcus pneumoniae among children with upper respiratory infection.

METHODSNasopharygeal swabs were collected from children with upper respiratory infection visiting the outpatient department of Beijing Children′s Hospital between March 2013 and February 2014. The antibiotic susceptibility was tested by Etest method, and the serotype was determined by Quellung reaction.

RESULTSThe nasopharyngeal carriage rate for Streptococcus pneumoniae was 23.8% (699/2 941). One hundred isolates were randomly chosen for antimicrobial susceptiblity test and serotyping. Up to 98.0% isolates were susceptible to parenteral penicillin. The susceptible rate against oral penicillin, however, was 33.0%. The non-susceptible rate to erythromycin and azithromycin was 97.0%. The multi-drug resistance rate was up to 86.0%. The common serotypes were 6A(12.0%), 19F(12.0%), 6B(10.0%), 23F(9.0%) and 14(8.0%). The coverage rates of 7-, 10- and 13-valent pneumococcal conjugate vaccine were 41.0%, 42.0% and 59.0% respectively.

CONCLUSIONSAbout 25% of children with upper respiratory infection are nasopharyngeal colonized by Streptococcus pneumoniae. The isolates show a high antimicrobial resistance. The 13-valent pneumococcal conjugate vaccine covers about 60.0% of the isolates.

Adolescent ; Carrier State ; epidemiology ; microbiology ; Child ; Child, Preschool ; Drug Resistance, Bacterial ; Female ; Humans ; Infant ; Male ; Nasopharynx ; microbiology ; Pneumococcal Vaccines ; immunology ; Respiratory Tract Infections ; microbiology ; Serotyping ; Streptococcus pneumoniae ; classification ; drug effects ; isolation & purification

OBJECTIVETo investigate molecular characterization of streptococcus pyogenes isolates involved in an outbreak of scarlet fever in China in 2011.

METHODSSeventy-four Streptococcal pyogenes involved in an outbreak of scarlet fever were isolated from pediatric patients in the areas with high incidence in China from May to August of 2011. Emm genotyping, pulsed-field gel electrophoresis (PFGE), superantigen (SAg) genes and antimicrobial susceptibility profiling were analyzed for these isolates.

RESULTSA total of 4 different emm types were identified. Emm12 was the most prevalent type which contained four predominating PFGE patterns corresponding to four different virulence and superantigen profiles. Emm12 (79.7%) and emm1 (14.9%) accounted for approximately 94% of all the isolates. The speA gene was all negative in emm12 isolates and positive in emm1 isolates. All strains were resistant to erythromycin, and 89.4% of them were resistant to erythromycin, tracycline, and clindamycin simultaneously.

CONCLUSIONSeveral highly diversified clones with a high macrolide resistance rate comprise a predominant proportion of circulating strains, though no new emm type was found in this outbreak. The data provide a baseline for further surveillance of scarlet fever, which may contribute to the explanation of the outbreak and development of a GAS vaccine in China.

Anti-Bacterial Agents ; administration & dosage ; therapeutic use ; Child ; China ; epidemiology ; Disease Outbreaks ; Drug Resistance, Bacterial ; Electrophoresis, Gel, Pulsed-Field ; Humans ; Incidence ; Molecular Epidemiology ; Scarlet Fever ; drug therapy ; epidemiology ; microbiology ; Streptococcus pyogenes ; drug effects ; genetics ; isolation & purification ; pathogenicity ; Virulence

OBJECTIVETo investigate the genetic features of drug resistance to group A streptococcus(GAS) and macrolides antibiotics among pediatric patients in Beijing 2012.

METHODSA total of 199 strains of GAS were collected from 36 hospitals in Beijing between May and July, 2012. All strains were isolated from oropharyngeal swabs. The minimum inhibitory concentrations (MICs) of ten antibiotics (penicillin, ampicillin, erythromycin, clindamycin, tetracycline, levofloxacin, tigecycline, vancomycin, linezolid and streptogramin) were detected by VITEK-2 compact with GPS-67 test kit. The genes encoding macrolides resistance (ermA, ermB and mefA ) were amplified and tested by PCR. The macrolides resistant phenotype of group A streptococcus was detected by double disc test (D-test).

RESULTSAmong 199 strains of GAS collected in this study, 101(50.8%) were from suburbs and the other 98(49.2%) were from urban areas. 111(55.8%) strains were collected from scarlet fever patients while the other 88(44.2%) were from oropharyngeal infection cases. All the strains were sensitive to penicillin and ampicillin, and the percentage of resistance to erythromycin, clindamycin and tetracycline were 96.5% (192/199), 95.5% (190/199) and 92.0% (183/199), respectively. All strains were susceptible to levofloxacin, tigecycline, vancomycin, linezolid and streptogramin. The rates of resistance to erythromycin, clindamycin and tetracycline were different in different districts, however, the difference in it between ages and clinical diagnosis did not show statistical significance (P > 0.05) . The detected rate of drug resistance gene ermB was 98.5% (196/199). The gene ermA was only detected out in 5 strains and the gene mefA was not detected out. 199 strains showed A macrolides resistant phenotype cMLS, while the phenotype iMLS was not found in this study.

CONCLUSIONThis study demonstrates the high level of clindamycin resistance in group A streptococcus collected from children in Beijing, 2012. The macrolides resistance of group A streptococcus was highly prevalent in Beijing, and the dominant phenotype was cMLS mediated by gene ermB.

Anti-Bacterial Agents ; pharmacology ; Bacterial Proteins ; genetics ; Child ; Child, Preschool ; China ; epidemiology ; Drug Resistance, Multiple, Bacterial ; genetics ; Genotype ; Humans ; Macrolides ; pharmacology ; Streptococcal Infections ; epidemiology ; microbiology ; Streptococcus pyogenes ; drug effects ; genetics ; isolation & purification

BACKGROUNDErythromycin-resistant Streptococcus pneumoniae isolates that causing invasive pneumococcal diseases (IPD) in Chinese children remain uncharacterized. This study aims to identify the resistance genes associated with erythromycin resistance and to determine the genetic relationships of IPD isolates in Chinese children.

METHODSA total of 171 S. pneumoniae strains were isolated from 11 medical centers in China from 2006 to 2008. All the isolates were characterized via serotyping and antibiotic susceptibility determination. The erythromycin-resistant isolates were further characterized via ermB and mefA gene detection, multi-locus sequence typing analysis, and pulsed-field gel electrophoresis.

RESULTSA total of 164 (95.9%) isolates showed resistance to erythromycin, of which 162 strains with high high-level resistance (MIC ≥ 256 µg/ml). A total of 104 (63.4%) isolates carry the ermB gene alone, whereas 59 (36.0%) harbor both ermB and mefA genes. Of the 59 strains, 54 were of serotypes 19A and 19F and were identified as highly clonal and related to the Taiwan(19F)-14 clone.

CONCLUSIONSThe erythromycin resistance rate in IPD isolates is significantly high and is predominantly mediated by the ermB gene. Isolates that carry both ermB and mefA genes are predominantly of serotypes 19A and 19F.

Adolescent ; Anti-Bacterial Agents ; pharmacology ; Child ; Child, Preschool ; Drug Resistance, Bacterial ; Electrophoresis, Gel, Pulsed-Field ; Erythromycin ; pharmacology ; Humans ; Infant ; Multilocus Sequence Typing ; Pneumococcal Infections ; microbiology ; Serotyping ; Streptococcus pneumoniae ; classification ; drug effects ; genetics ; isolation & purification

We investigated serotype distribution and antimicrobial resistance of pneumococcal carriage isolates from children after optional immunization with the 7-valent pneumococcal conjugate vaccine (PCV7) in Korea. From June 2009 to June 2010, 205 (16.5%) pneumococcal isolates were obtained from 1,243 nasopharyngeal aspirates of infants and children at Seoul National University Children's Hospital, Korea. Serotype was determined by Quellung reaction and antibiotic susceptibility was tested by E-test. The results were compared to previous studies done in the pre-PCV7 period. In this study, the most common serotypes were 6A (15.3%), 19A (14.7%), 19F (10.2%), 35B (7.3%), and 6D (5.6%). The proportion of PCV7 serotypes decreased from 61.9% to 23.8% (P < 0.001). The overall penicillin nonsusceptibility rate increased from 83.5% to 95.4% (P = 0.001). This study demonstrates the impact of optional PCV7 vaccination in Korea; the proportion of all PCV7 serotypes except 19F decreased while antimicrobial resistant serotypes 6A and 19A further increased.
Anti-Bacterial Agents/pharmacology ; Child, Preschool ; Drug Resistance, Bacterial/drug effects ; Humans ; Infant ; Microbial Sensitivity Tests ; Nasopharynx/*microbiology ; Pneumococcal Infections/immunology/prevention & control ; Republic of Korea ; Serotyping ; Streptococcus pneumoniae/classification/*isolation & purification ; Vaccination ; Vaccines, Conjugate/*immunology