ANTIFUNGAL POTENTIAL OF PLANT SPECIES FROM BRAZILIAN CAATINGA AGAINST DERMATOPHYTES

Trichophyton rubrum and Trichophyton mentagrophytes complex, or Trichophyton spp. are the main etiologic agents of dermatophytosis, whose treatment is limited by the high cost of antifungal treatments, their various side effects, and the emergence of resistance amongst these species. This study evaluated the in vitro antidermatophytic activity of 23 crude extracts from nine plant species of semiarid vegetation (caatinga) found in Brazil. The extracts were tested at concentrations ranging from 1.95 to 1,000.0 mg/mL by broth microdilution assay against the reference strains T. rubrum ATCC 28189 and T. mentagrophytesATCC 11481, and 33 clinical isolates of dermatophytes. All plants showed a fungicidal effect against both fungal species, with MIC/MFC values of the active extracts ranging from 15.6 to 250.0 µg/mL. Selected extracts of Eugenia uniflora (AcE), Libidibia ferrea (AE), and Persea americana (AcE) also exhibited a fungicidal effect against all clinical isolates of T. rubrum and T. mentagrophytes complex. This is the first report of the antifungal activity of Schinus terebinthifolius, Piptadenia colubrina, Parapiptadenia rigida, Mimosa ophthalmocentra, and Persea americana against both dermatophyte species

Effect of Eugenol against Streptococcus agalactiae

Streptococcus agalactiae (group B streptococci (GBS)) is an important infections agent in newborns associated with maternal vaginal colonization. Intrapartum antibiotic prophylaxis in GBS-colonized pregnant women has led to a significant reduction in the incidence of early neonatal infection in various geographic regions. However, this strategy may lead to resistance selecting among GBS, indicating the need for new alternatives to prevent bacterial transmission and even to treat GBS infections. This study reported for the first time the effect of eugenol on GBS isolated from colonized women, alone and in combination with silver nanoparticles produced by Fusarium oxysporum (AgNPbio). Eugenol showed a bactericidal effect against planktonic cells of all GBS strains, and this effect appeared to be time-dependent as judged by the time-kill curves and viability analysis. Combination of eugenol with AgNPbio resulted in a strong synergistic activity, significantly reducing the minimum inhibitory concentration values of both compounds. Scanning and transmission electron microscopy revealed fragmented cells and changes in bacterial morphology after incubation with eugenol. In addition, eugenol inhibited the viability of sessile cells during biofilm formation and in mature biofilms. These results indicate the potential of eugenol as an alternative for controlling GBS infections

Emergência de Staphylococcus aureus resistentes aos antimicrobianos: um desafio contínuo

Objetivo: Descrever o conhecimento atual dos principais mecanismos de resistência aos β-lactâmicos e glicopeptídeos apresentados por Staphylococcus aureus. Metodologia: Foram selecionados artigos de pesquisa originais e de revisão disponíveis nas bases de dados PubMed, Portal Periódicos CAPES e SCIELO. Os seguintes descritores foram utilizados: methicillin-resistant Staphylococcus aureus (MRSA), MRSA infection, vancomycin-intermediate S. aureus (VISA), heterogeneous-VISA (hVISA), staphylococcal cassete chromosome mec (SCCmec). A seleção dos artigos foi baseada em dois critérios: 1) publicação entre os anos 2000 e 2014 (até a data de submissão); 2) artigos cujos autores contribuíram com descobertas relevantes sobre os temas, independente do ano de publicação. Resultados: As consultas realizadas nos bancos de dados resultaram em 268 artigos, dos quais 59 foram utilizados para escrita dessa revisão. Conclusão: As comunidades, médica e científica, são constantemente desafiadas com a emergência de bactérias resistentes aos antimicrobianos. MRSA continua sendo um grande problema de saúde pública no mundo todo. Resistência aos glicopeptídeos (vancomicina e teicoplanina), uma das últimas escolhas para o tratamento intravenoso de infecções causadas por cepas de MRSA também tem sido descrita. A partir deste novo cenário, observou-se o surgimento de VRSA (vancomycin-resistant S. aureus), VISA (vancomycin-intermediate S. aureus) e hVISA (heterogeneous-VISA). Esses dados indicam a necessidade urgente de adoção de métodos mais sensíveis e rigorosos para detecção dessas cepas no laboratório de microbiologia clínica. Esta medida pode contribuir no sucesso do tratamento e prevenção de infecções causadas por essas bactérias

Prevalence and antimicrobial susceptibility profile of Streptococcus agalactiae in pregnant women seen at the University Hospital of Londrina, Paraná, Brazil

A retrospective study of pregnant women seen at the University Hospital of Londrina, Paraná, Brazil was performed to determine the prevalence of Group B Streptococcus (GBS) vaginal-rectal colonization, and the GBS susceptibility for antimicrobials used in intrapartum antibiotic prophylaxis. A vaginal-rectal swab was collected from 2,901 women between 35 and 37 weeks of gestation. Of these, 528 (18.2%) had a positive culture for GBS, and 0.4%, 10.2% and 10% of the isolates were resistant to penicillin, erythromycin and clindamycin, respectively. These results highlight the importance of continuous surveillance of GBS colonization in pregnant women for preventing GBS infections in neonates

Evolution of resistance of Klebsiella pneumoniae in Londrina University Hospital from 2000 to 2011

The present study aimed to evaluate the evolution of antibiotic resistance in clinical isolates of Klebsiella pneumoniae in the period of 2000 to 2011, at the University Hospital of Londrina (HU-UEL). A retrospective analysis of 2,318 antimicrobial susceptibility tests of K. pneumoniae was performed from a database of the Clinical Laboratory of Microbiology of the University Hospital. In the period of 2000 to 2009, the main mechanism of resistance observed to ?-lactam antimicrobials was due to the production of ESBL ?-lactamase type (?-lactamase wide spectrum), which can be verified by the increased resistance of K. pneumoniae to 3rd generation cephalosporins and cefepime. However, the first strains of K. pneumoniae carbapenemase-producing appeared in 2009, compromising the efficacy of carbapenems. The rates of resistance to ertapenem ranged from 16%, in 2005, to 40% in 2011. Another class of committed antibiotics was the fluoroquinolones; for ciprofloxacin, resistance rates ranged from 13% to 62%, in 2001 and 2011, respectively. Aminoglycosides exhibited oscillations of resistance during the period studied, reaching, in 2011, values of 56% and 30% for gentamicin and amikacin, respectively. Meanwhile, trimethoprim/ sulfamethoxazole and piperacillin/tazobactam reached about 60%, in the same period. Therefore, knowing the antimicrobial resistance of K. pneumoniae strains is essential for proper treatment of patients and adoption of appropriate measures that aims infection control, and proper use of these drugs

Effect of eugenol against streptococcus agalactiae and synergistic interaction with biologically produced silver nanoparticles

Streptococcus agalactiae (group B streptococci (GBS)) is an important infections agent in newborns associated with maternal vaginal colonization. Intrapartumantibiotic prophylaxis in GBS-colonized pregnant women has led to a significant reduction in the incidence of early neonatal infection in various geographic regions. However, this strategy may lead to resistance selecting among GBS, indicating the need for new alternatives to prevent bacterial transmission and even to treat GBS infections. This study reported for the first time the effect of eugenol on GBS isolated from colonized women, alone and in combination with silver nanoparticles produced by Fusarium oxysporum (AgNPbio). Eugenol showed a bactericidal effect against planktonic cells of all GBS strains, and this effect appeared to be time-dependent as judged by the time-kill curves and viability analysis. Combination of eugenol with AgNPbio resulted in a strong synergistic activity, significantly reducing the minimum inhibitory concentration values of both compounds. Scanning and transmission electron microscopy revealed fragmented cells and changes in bacterial morphology after incubation with eugenol. In addition, eugenol inhibited the viability of sessile cells during biofilm formation and in mature biofilms. These results indicate the potential of eugenol as an alternative for controlling GBS infections2015CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPES402728/2013-0sem informaçãoPrograma de Pos-Graduacao em Microbiologia da Universidade Estadual de Londrin

Vancomycin-resistant Enterococcus spp.: clinical characteristics and risk factors

Vancomycin-resistant Enterococci (VRE) have emerged as a relevant multidrug-resistant pathogen and potencially lethal etiology of healthcare associated infections worldwide. This study intends to show the epidemiology and clinical characteristics of patients with VRE in a Hospital in South Brazil. A retrospective study was conducted from January 2005 to November 2007. A total of 122 VRE were identified in this period at the University Hospital of Londrina. All patients with VRE clinical culture have identified and their medical records have reviewed. The presence of colonization was evaluated through rectal swab cultures, and the species identification of clinical samples was performed by automated method MicroScan®. The mean age of patients was 54 years. Urinary tract (68.0%) and blood (23.8%) were the most frequent sites, and ICU was the largest sector of occurrence (49.2%). E. faecium was the predominant species, in 82.8% of cases. The risk factors presents were length of hospitalization (mean 58.2 days), previous use of antimicrobials and invasive procedure, such as use of central venous catheter, urinary catheter and mechanical ventilation. Control barriers and surveillance cultures are essential to prevent the VRE spread. The results obtained in this study contribute to a better understanding of the epidemiological dynamics of infections and the spread of VRE in University Hospital of Londrina

Antibacterial combination of oleoresin from Copaifera multijuga hayne and biogenic silver nanoparticles towards Streptococcus agalactiae

Background: Streptococcus agalactiae (group B Streptococcus - GBS) remains a leading cause of neonatal infections and an important cause of invasive infections in adults with underlying conditions. Methods: This study evaluated for the first time the effect of an oleoresin collected from Copaifera multijuga Hayne (copaiba oil) alone or in combination with silver nanoparticles produced by green synthesis using Fusarium oxysporum (AgNPbio) against planktonic and sessile cells of GBS isolated from colonized women. Results: Copaiba oil showed a dose-dependent bactericidal activity against planktonic GBS strains, including those resistant to erythromycin and/or clindamycin. Scanning and transmission electron microscopy of GBS treated with copaiba oil revealed morphological and ultrastructural alterations, displaying disruption of the cell wall and decreased electron density due to leakage of cytoplasmic content. Copaiba oil also exhibited antibacterial activity against biofilms of GBS strains, inhibiting their formation as well as the viability of mature biofilms. In addition, the combination of copaiba oil with AgNPbio resulted in a synergistic effect against planktonic cells and biofilm formation, reducing the minimal inhibitory concentration values of both compounds. No hemolytic activity was detected for both compounds. Conclusion: These results indicate the potential of copaiba oil, alone or in combination with AgNPbio, for the development of new alternative strategies for controlling GBS infections182177190CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPES402728/2013-0sem informaçã