OBJECTIVEThis study examined the antimicrobial activity of Cannabis sativa, Thuja orientalis and Psidium guajava against methicillin-resistant Staphylococcus aureus (MRSA) and used a standardized purification protocol to determine the presence and abundance of bioactive compounds in the leaf extracts.

METHODSIn vitro antimicrobial activities of the ethanolic extracts of C. sativa, T. orientalis and P. guajava were tested against MRSA. The presence of bioactive molecules in these three leaves was evaluated using biochemical assays and high-performance thin-layer chromatography (HPTLC).

RESULTSResistance to methicillin, penicillin, oxacillin and cefoxitin was observed in each of the clinical and nonclinical MRSA isolates. However, they were still vulnerable to vancomycin. Used individually, the 50% extract of each plant leaf inhibited MRSA growth. A profound synergism was observed when C. sativa was used in combination with T. orientalis (1:1) and when P. guajava was used in combination with T. orientalis (1:1). This was shown by larger zones of inhibition. This synergism was probably due to the combined inhibitory effect of phenolics present in the leaf extracts (i.e., quercetin and gallic acid) and catechin, as detected by HPTLC.

CONCLUSIONThe leaf extracts of C. sativa, T. orientalis and P. guajava had potential for the control of both hospital- and community-acquired MRSA. Moreover, the inhibitory effect was enhanced when extracts were used in combination.

Anti-Bacterial Agents ; pharmacology ; Cannabis ; Drug Resistance ; drug effects ; Humans ; Methicillin ; pharmacology ; Methicillin-Resistant Staphylococcus aureus ; drug effects ; growth & development ; Microbial Sensitivity Tests ; Phytotherapy ; Plant Extracts ; pharmacology ; Plant Leaves ; Psidium ; Staphylococcal Infections ; drug therapy ; microbiology ; Thuja

Staphylococcus aureus, or methicillin-resistant S. aureus (MRSA), is a significant pathogen in both nosocomial and community infections. Community-associated MRSA (CA-MRSA) strains tend to be multi-drug resistant and to invade hospital settings. This study aimed to assess the antimicrobial resistance and molecular characteristicsof nasal S. aureus among newlyadmitted inpatients.In the present study, 66 S. aureus isolates, including 10 healthcare-associated MRSA (HA-MRSA), 8 CA-MRSA, and 48 methicillin-sensitive S. aureus (MSSA) strains, were found in the nasal cavities of 62 patients by screening 292 newlyadmitted patients. Antimicrobial resistance and molecular characteristics of these isolates, including spa-type, sequence type (ST) and SCCmec type, were investigated. All isolates were sensitive to linezolid, teicoplanin, and quinupristin/dalfopristin, but high levels of resistance to penicillin and erythromycin were detected. According to D-test and erm gene detection results, the cMLSB and iMLSB phenotypes were detected in 24 and 16 isolates, respectively. All 10 HA-MRSA strains displayed the cMLSB phenotypemediated by ermA or ermA/ermC, while the cMLSB CA-MRSA and MSSA strains carried the ermB gene. Molecular characterization revealedall 10 HA-MRSA strains were derived from the ST239-SCCmec III clone, and four out of eight CA-MRSA strains were t437-ST59-SCCmec V. The results suggest that patients play an indispensable role in transmitting epidemic CA-MRSA and HA-MRSA strains.
Anti-Bacterial Agents/*pharmacology ; Bacterial Proteins/genetics ; Drug Resistance, Multiple, Bacterial/genetics ; Humans ; Inpatients ; Methicillin-Resistant Staphylococcus aureus/*drug effects/genetics/isolation & purification ; Methyltransferases/genetics ; Microbial Sensitivity Tests ; Nasal Cavity/*microbiology ; Staphylococcal Infections/diagnosis/microbiology ; Staphylococcus aureus/*drug effects/genetics/isolation & purification

BACKGROUND: We estimated the prevalence and clinical impact of heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA). The concordance between macromethod and glycopeptide resistance detection (GRD) E tests was determined. In addition, predictors of clinical outcomes in hospitalized patients with S. aureus bacteremia (SAB) or pneumonia (SAP) were evaluated. METHODS: We obtained 229 consecutive S. aureus isolates from all hospitalized patients at two university hospitals located in Busan and Yangsan, Korea. Standard, macromethod, and GRD E tests were performed. Additionally, we reviewed the medical records of all patients. Among the 229 patients, predictors of clinical outcomes were analyzed for 107 patients with SAB and 39 with SAP. RESULTS: Among the 229 isolates, 34.5% of S. aureus isolates and 50.7% of methicillin-resistant S. aureus isolates exhibited the hVISA phenotype based on the macromethod E test. hVISA was nearly associated with treatment failure in patients with SAB (P=0.054) and was significantly associated with treatment failure in patients with SAP (P=0.014). However, hVISA was not associated with 30-day mortality in patients with SAB or SAP. The concordance between the macromethod and GRD E tests was 84.2%. CONCLUSIONS: hVISA is quite common in the southeastern part of Korea. hVISA is associated with treatment failure in patients with SAP.
Aged ; Anti-Bacterial Agents/*pharmacology/therapeutic use ; Bacteremia/drug therapy/epidemiology/microbiology ; Drug Resistance, Bacterial/*drug effects ; Female ; Hospital Mortality ; Hospitalization ; Humans ; Male ; Methicillin-Resistant Staphylococcus aureus/drug effects/isolation & purification ; Microbial Sensitivity Tests ; Middle Aged ; Phenotype ; Pneumonia/drug therapy/epidemiology/microbiology ; Prevalence ; Republic of Korea/epidemiology ; Staphylococcus aureus/*drug effects/isolation & purification ; Teicoplanin/pharmacology ; Vancomycin/pharmacology/*therapeutic use

BACKGROUND/AIMS: Intranasal mupirocin and chlorhexidine bathing are candidate strategies to prevent healthcare-associated infections caused by methicillin-resistant Staphylococcus aureus (MRSA). In Korea, intranasal mupirocin is not available, and mupirocin ointment, an over-the-counter drug, has been used indiscriminately. Furthermore, because it is covered by health insurance, mupirocin is easy to prescribe within hospitals. METHODS: We performed a mupirocin drug utilization review (DUR) within Hallym University Sacred Heart Hospital. Annual use of mupirocin was investigated between 2003 and 2013, and monthly consumption of mupirocin was assessed during the final 2-year period. The DUR focused on August 2012, the period of highest use of mupirocin. Also, we investigated trends in mupirocin resistance in MRSA between 2011 and 2013. RESULTS: Annual consumption of mupirocin increased from 3,529 tubes in 2003 to 6,475 tubes in 2013. During August 2012, 817 tubes were prescribed to 598 patients; of these, 84.9% were prescribed to outpatients, and 77.6% at the dermatology department. The most common indication was prevention of skin infections (84.9%), and the ointment was combined with systemic antibiotics in 62.9% of cases. The average duration of systemic antibiotic administration was about 7.8 days. The rate of low-level mupirocin resistance in MRSA increased from 8.0% to 22.0%, and that of high-level mupirocin resistance increased from about 4.0% to about 7.5%. CONCLUSIONS: Inappropriate use of mupirocin is prevalent. Considering the increase in resistance and the future application of intranasal mupirocin, prophylactic use of mupirocin in dermatology departments should be reconsidered.
Administration, Cutaneous ; Anti-Bacterial Agents/*administration & dosage/adverse effects ; Drug Prescriptions ; Drug Resistance, Multiple, Bacterial ; Drug Utilization Review ; *Hospitals, University ; Humans ; Inappropriate Prescribing/*trends ; Methicillin-Resistant Staphylococcus aureus/*drug effects ; Microbial Sensitivity Tests ; Mupirocin/*administration & dosage/adverse effects ; Ointments ; Practice Patterns, Physicians'/*trends ; Predictive Value of Tests ; Republic of Korea ; Retrospective Studies ; Staphylococcal Skin Infections/diagnosis/*drug therapy/microbiology ; Time Factors

OBJECTIVETo investigate the genotype of staphylococcal chromosomal cassette mec (SCCmec) in methicillin-resistant Staphylococcus aureus (MRSA) isolated from burn wards and its current status of drug resistance.

METHODSOne hundred and seventy-nine strains of Staphylococcus aureus were isolated from wound excretion, blood, and sputum samples of patients that were admitted to ICU or public wards of our Department of Burns and Plastic Surgery from September 2012 to September 2013. Among them, 68 strains were from ICU and 111 strains from public wards. The MRSA phenotype of Staphylococcus aureus was detected with cefoxitin K-B disk diffusion method, and the isolation rates of MRSA in ICU and public wards were compared. Genotyping of SCCmec was performed by PCR in strains of MRSA. In the meantime, the identification result of MRSA by K-B method was verified through detecting methicillin-resistant determinant mecA. The antimicrobial resistance of MRSA and methicillin-sensitive Staphylococcus aureus (MSSA) to 23 kinds of commonly used antibiotics in clinic were detected by K-B disk diffusion method. Except for the antibiotics to which the resistant rates of MRSA were 100.0% or 0, the resistant rates of SCCmecIII MRSA and non-SCCmec III MRSA to the rest of antibiotics were compared. Data were processed with Pearson chi-square test or corrected chi-square test.

RESULTSOne hundred and forty-eight strains out of the 179 Staphylococcus aureus were identified as MRSA (accounting for 82.7%), among which 62 were originated from ICU and 86 from public wards. The rest 31 strains of Staphylococcus aureus were MSSA, accounting for 17.3%. The percentage of MRSA in the isolated Staphylococcus aureus was 91.2% (62/68) in ICU, which was significantly higher than that in the public wards [77.5% (86/111), χ2 = 5.526, P = 0.019]. PCR detection showed that the 148 strains of MRSA harbored the mecA gene, out of which 106 strains were SCCmec III positive, accounting for 71.6%. The percentages of SCCmec III type MRSA in MRSA isolated from ICU and public wards were respectively 72.6% (45/62) and 70.9% (61/86), showing no statistically significant difference (χ2 = 0.048, P = 0.826). The 148 strains of MRSA were 100.0% resistant to a total of 8 kinds of antibiotics including penicillin and cephalosporins, but it was 0 for vancomycin, teicoplanin, linezolid, tigecycline, nitrofurantoin, and quinupristin/dalfopristin. Except for the 6 kinds of antibiotics to which the resistant rates of MRSA and MSSA were 0, resistant rates of MRSA to the remaining 17 kinds of antibiotics were significantly higher than those of MSSA (with χ2 values from 4.091 to 138.546, P < 0.05 or P < 0.01). Resistant rates of the 106 strains of SCCmecIII type MRSA to levofloxacin, ciprofloxacin, rifampicin, tetracycline, erythrocin, lincomycin, gentamicin, clindamycin were respectively 56.6% (60/106), 85.8% (91/106), 89.6% (95/106), 86.8% (92/106), 84.9% (90/106), 78.3% (83/106), 92.5% (98/106), 74.5% (79/106), and they were significantly higher than those of the 42 strains of non-SCCmec III type MRSA [33.3% (14/42), 61.9% (26/42), 71.4% (30/42), 66.7% (28/42), 69.0% (29/42), 57.1% (24/42), 71.4% (30/42), 52.4% (22/42), with χ2 values from 4.801 to 11.377, P < 0.05 or P < 0.01].

CONCLUSIONSIsolation rate of MRSA from burn wards in our hospital is high, and drug resistance status of this strain against antibiotics is very serious. SCCmec III is the major genotype of the isolated MRSA, but no strains resistant to the glycopeptide antibiotics are found.

Anti-Bacterial Agents ; pharmacology ; Burns ; microbiology ; Drug Resistance, Bacterial ; genetics ; Drug Resistance, Multiple ; Genes, Bacterial ; genetics ; Genotype ; Humans ; Methicillin-Resistant Staphylococcus aureus ; drug effects ; genetics ; isolation & purification ; Microbial Sensitivity Tests ; Staphylococcal Infections ; drug therapy ; epidemiology

The crude extracts of the fermentation broth from a marine sediment-derived actinomycete strain, Saccharothrix sp. 10-10, showed significant antibacterial activities against drug-resistant pathogens. A genome-mining PCR-based experiment targeting the genes encoding key enzymes involved in the biosynthesis of secondary metabolites indicated that the strain 10-10 showed the potential to produce tetracenomycin-like compounds. Further chemical investigation of the cultures of this strain led to the identification of two antibiotics, including a tetracenomycin (Tcm) analogs, Tcm X (1), and a tomaymycin derivative, oxotomaymycin (2). Their structures were identified by spectroscopic data analysis, including UV, 1D-NMR, 2D-NMR and MS spectra. Tcm X (1) showed moderate antibacterial activities against a number of drug-resistant pathogens, including methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE) pathogens, with the MIC values in the range of 32-64 microg x mL(-1). In addition, 1 also displayed significant cytotoxic activities against human cancer cell lines, including HL60 (leukemia), HepG2 (liver), and MCF-7 (breast) with the IC 50 values of 5.1, 9.7 and 18.0 micromol x L(-1), respectively. Guided by the PCR-based gene sequence analysis, Tcm X (1) and oxotomaymycin (2) were identified from the genus of Saccharothrix and their 13C NMR data were correctly assigned on the basis of 2D NMR spectroscopic data analysis for the first time.
Actinomycetales ; chemistry ; genetics ; Anti-Bacterial Agents ; chemistry ; isolation & purification ; pharmacology ; Antineoplastic Agents ; chemistry ; isolation & purification ; pharmacology ; Benzodiazepinones ; chemistry ; isolation & purification ; pharmacology ; Cell Line, Tumor ; Data Mining ; methods ; Drug Resistance, Bacterial ; Enterococcus faecalis ; drug effects ; Fermentation ; Genomics ; Humans ; Inhibitory Concentration 50 ; Marine Biology ; Methicillin-Resistant Staphylococcus aureus ; drug effects ; Microbial Sensitivity Tests ; Molecular Structure ; Naphthacenes ; chemistry ; isolation & purification ; pharmacology ; Phylogeny ; Staphylococcus epidermidis ; drug effects

OBJECTIVETo analyze the change in drug resistance of Staphylococcus aureus (SAU) in the PLA general hospital from January 2008 to December 2012, and to provide solid evidence to support the rational use of antibiotics for clinical applications.

METHODSThe SAU strains isolated from clinical samples in the hospital were collected and subjected to the Kirby-Bauer disk diffusion test. The results were assessed based on the 2002 American National Committee for Clinical Laboratory Standards (NCCLS) guidelines.

RESULTSSAU strains were mainly isolated from sputum, urine, blood and wound excreta and distributed in penology, neurology wards, orthopedics and surgery ICU wards. Except for glycopeptide drugs, methicillin-resistant Staphylococcus aureus (MRSA) had a higher drug resistance rate than those of the other drugs and had significantly more resistance than methicillin-sensitive Staphylococcus aureus (MSSA) (P < 0.05). In the dynamic observation of drug resistance, we discovered a gradual increase in drug resistance to fourteen test drugs during the last five years.

CONCLUSIONDrug resistance rate of SAU stayed at a higher level over the last five years; moreover, the detection ratio of MRSA keeps rising year by year. It is crucial for physicians to use antibiotics rationally and monitor the change in drug resistance in a dynamic way.

Anti-Bacterial Agents ; pharmacology ; Drug Resistance, Multiple, Bacterial ; Humans ; Methicillin-Resistant Staphylococcus aureus ; drug effects ; Staphylococcal Infections ; drug therapy ; Staphylococcus aureus ; drug effects

PURPOSE: The purpose of this study was to identify vancomycin-resistant enterococcus (VRE) colonization rate in patients admitted to the intensive care unit (ICU), associated risk factors and clinical outcomes for VRE colonization. METHODS: Of the 7,703 patients admitted to the ICUs between January, 2008 and December, 2010, medical records of 554 VRE colonized and 503 uncolonized patients were reviewed retrospectively. To analyzed the impact of colonization on patients' clinical outcomes, 199 VRE colonized patients were matched with 199 uncolonized patients using a propensity score matching method. RESULTS: During the study period, 567 (7.2%) of the 7,703 patients were colonized with VRE. Multivariate analysis identified the following independent risk factors for VRE colonization: use of antibiotics (odds ratio [OR]=3.33), having bedsores (OR=2.92), having invasive devices (OR=2.29), methicillin-resistant Staphylococcus aureus co-colonization (OR=1.84), and previous hospitalization (OR=1.74). VRE colonized patients were more likely to have infectious diseases than uncolonized patients. VRE colonization was associated with prolonged hospitalization and higher mortality. CONCLUSION: Strict infection control program including preemptive isolation for high-risk group may be helpful. Further research needs to be done to investigate the effects of active surveillance program on the incidence of colonization or infection with VRE in the ICU.
Adult ; Aged ; Anti-Bacterial Agents/pharmacology ; Enterococcus/drug effects/*isolation & purification ; Female ; Hospitalization ; Hospitals, University ; Humans ; Infection Control ; Intensive Care Units ; Length of Stay ; Male ; Methicillin-Resistant Staphylococcus aureus/isolation & purification ; Middle Aged ; Retrospective Studies ; Risk Factors ; Staphylococcal Infections/*epidemiology ; Vancomycin/pharmacology ; Vancomycin Resistance/drug effects

OBJECTIVETo study the distribution and drug resistance of methicillin resistant Staphylococcus strains in various specimens of inpatients in burn wards, and to provide reference for clinical treatment.

METHODSBacteria were isolated from specimens of wound exudate, blood, sputum, and bronchoalveolar lavage fluid etc., which were collected from patients hospitalized in our burn wards from January 2008 to December 2010. The bacteria were routinely cultured and identified. Drug resistance of the Staphylococci to 15 antibiotics commonly used in clinic was identified by K-B disk diffusion method. Data were processed with statistical software WHONET 5.5. The homology of 40 strains of methicillin resistant Staphylococcus aureus (MRSA) was analyzed by pulsed-field gel electrophoresis (PFGE).

RESULTSAltogether 386 strains of Staphylococcus were isolated, including 196 strains of Staphylococcus aureus and 190 strains of coagulase negative Staphylococcus. The mean annual isolation rates of MRSA and methicillin resistant coagulase negative Staphylococcus (MRCoNS) were respectively 73.00% (143/196) and 74.20% (141/190). The resistance rates of MRSA and MRCoNS to β-lactams drugs, such as penicillin, oxacillin, cefazolin, and cefuroxime were 100.00% in every year. No Staphylococcus strains resistant to vancomycin, teicoplanin, or linezolid were found. Three different PFGE patterns A, B, and C were identified among 40 MRSA strains, including 33 strains of type A (30 strains in sub-type A1 and 3 strains in sub-type A2), 6 strains of type B (respectively 3 strains in sub-types B1 and B2), and 1 strain of type C.

CONCLUSIONSThe isolation rates of MRSA and MRCoNS were high in our burn wards from January 2008 to December 2010. All of them showed strong drug resistance property, and they were multidrug resistant. The most prevalent strain was PFGE type A.

Burns ; microbiology ; Drug Resistance, Multiple, Bacterial ; Humans ; Methicillin-Resistant Staphylococcus aureus ; drug effects

OBJECTIVETo Isolate, purify, characterize, and evaluate the bioactive compounds from the sponge-derived fungus Penicillium sp. FF001 and to elucidate its structure.

METHODSThe fungal strain FF001 with an interesting bioactivity profile was isolated from a marine Fijian sponge Melophlus sp. Based on conidiophores aggregation, conidia development and mycelia morphological characteristics, the isolate FF001 was classically identified as a Penicillium sp. The bioactive compound was identified using various spectral analysis of UV, high resolution electrospray ionization mass spectra, 1H and 13C NMR spectral data. Further minimum inhibitory concentrations (MICs) assay and brine shrimp cytotoxicity assay were also carried out to evaluate the biological properties of the purified compound.

RESULTSBioassay guided fractionation of the EtOAc extract of a static culture of this Penicillium sp. by different chromatographic methods led the isolation of an antibacterial, anticryptococcal and cytotoxic active compound, which was identified as citrinin (1). Further, citrinin (1) is reported for its potent antibacterial activity against methicillin-resistant Staphylococcus aureus (S. aureus), rifampicin-resistant S. aureus, wild type S. aureus and vancomycin-resistant Enterococcus faecium showed MICs of 3.90, 0.97, 1.95 and 7.81 µg/mL, respectively. Further citrinin (1) displayed significant activity against the pathogenic yeast Cryptococcus neoformans (MIC 3.90 µg/mL), and exhibited cytotoxicity against brine shrimp larvae LD50 of 96 µg/mL.

CONCLUSIONSCitrinin (1) is reported from sponge associated Penicillium sp. from this study and for its strong antibacterial activity against multi-drug resistant human pathogens including cytotoxicity against brine shrimp larvae, which indicated that sponge associated Penicillium spp. are promising sources of natural bioactive metabolites.

Animals ; Anti-Bacterial Agents ; chemistry ; pharmacology ; Artemia ; drug effects ; Citrinin ; chemistry ; pharmacology ; Drug Resistance, Multiple, Bacterial ; drug effects ; Lethal Dose 50 ; Methicillin-Resistant Staphylococcus aureus ; drug effects ; Microbial Sensitivity Tests ; Penicillium ; chemistry ; cytology ; Porifera ; microbiology ; Toxicity Tests