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Arq. bras. med. vet. zootec. (Online) ; 72(3): 1047-1050, May-June, 2020. ilus
Article in Portuguese | ID: biblio-1129749


The aim of the present study was to evaluate the antibacterial behavior of polypyrrole nanoparticles (PPy-NPs) in water against biofilm producer or not S. aureus isolated from cows and goats with mastitis. One hundred and thirty-eight isolates of S. aureus were initially evaluated for biofilm formation by spectrophotometry in microplates. In addition, the minimum inhibition concentration (MIC) and minimum bactericidal concentration (MBC) of PPy-NPs in water for planktonic S. aureus were determined. From the bovine samples analyzed, 5 (4.46%) S. aureus isolates showed a strong biofilm production, 17 (15.18%) moderate production, 36 (32.14%) with weak production and 54 (48.21%) did not produce biofilms. Strains from goats (26) showed no biofilm production in 18 (69.23%) strains and weak biofilm production in 8 (30.76%) strains. The MIC and MBC of S. aureus to PPy-NPs were found in the same concentration (125搭/mL) in all strains tested, regardless of biofilm production or not. This finding provides a new insight into the interaction between PPy-NPs and S. aureus, and will offer potential benefits for the control of mastitis.(AU)

Animals , Female , Cattle , Pyrroles/administration & dosage , Staphylococcus aureus/drug effects , Goats/microbiology , Mastitis/veterinary , Biofilms , Anti-Bacterial Agents/therapeutic use
Braz. arch. biol. technol ; 63: e20190286, 2020. tab, graf
Article in English | LILACS | ID: biblio-1132191


Abstract This study aimed to develop and evaluate fermented milk by Lactobacillus reuteri LR92 with addition of juçara pulp (FMJ) and reuterin production in situ. The fermentation process was analyzed for 24 hours and the storage of FMJ for 30 days at 4 °C. During the fermentation, there was consumption of 25% (w / v) of lactose and increase of 0.01 to 0.85% (w / v) of lactic acid. The FMJ presented 0.43 ± 0.01 mM of reuterin, inhibiting Staphylococcus aureus strains under in vitro test. For the carbohydrates, the percentages (g.100g-1) found were 7.31 ± 1.07; 9.19 ± 0.82; 1.60 ± 0.50 and 0.08 ± 0.00 for sucrose, lactose, galactose and fructose respectively. The survival of L. reuteri, present in FMJ, was 2.47 log CFU / mL after 6 hours of gastrointestinal simulation. In sensory analysis FMJ received a grade 7 for global acceptance indicating good acceptance of the product.

Animals , Cultured Milk Products/microbiology , Functional Food/microbiology , Lactobacillus reuteri/metabolism , Euterpe/metabolism , Propane/metabolism , Staphylococcus aureus/drug effects , Lactic Acid , Anti-Infective Agents
Braz. arch. biol. technol ; 63: e20190339, 2020. graf
Article in English | LILACS | ID: biblio-1132187


Abstract Conventional orthodontic treatment with the use of stainless steel may be detrimental to oral health by promoting demineralizing lesions appearance and increasing adhesion and formation of bacterial biofilm, inducing the development of cavities. An alternative that has been researched to reduce the side effects of orthodontic treatment is the coating of materials with antimicrobial nanoparticles. Nanometric- sized particles increase their surface area and contact with the microbial membrane, consequently intensifying their bacteriostatic and bactericidal effect. In this work, hydrothermal synthesis, a "green" process was used to attach silver nanoparticles (AgNPs) to the surface of two different brands of orthodontic wires. The coated materials were analyzed for their physicochemical properties by scanning electron microscopy (SEM), X-ray diffraction (XRD) and differential scanning calorimetry (DSC), which showed the distribution of AgNPs along the wires without modifying their properties. In the microbiological test, one of the brands showed a statistically significant difference in microbial adhesion and biofilm formation by Staphylococcus aureus and Streptococcus mutans. Results lead to the conclusion that antimicrobial orthodontic wires coated with silver nanoparticles through hydrothermal synthesis is a promising material for the improvement of orthodontic treatment.

Orthodontic Wires , Staphylococcus aureus/drug effects , Streptococcus mutans/drug effects , Metal Nanoparticles , Anti-Bacterial Agents/pharmacology , Silver , Bacterial Adhesion , Calorimetry , Microscopy, Electron, Scanning , Dental Plaque , Linings
Braz. arch. biol. technol ; 63: e20190704, 2020. tab, graf
Article in English | LILACS | ID: biblio-1132229


Abstract To the moment, there is no ideal substance for home-based denture disinfection. This study assessed in vitro the antimicrobial effect of the hydroalcoholic extract of Eugenia uniflora and the effect on the physical properties of denture polymethylmethacrylate (PMMA). Candida albicans, Staphylococcus aureus, and Klebsiella oxytoca were isolated from samples of saliva collected from denture wearers. The extracts were produced in three concentrations, according to the Brazilian Pharmacopeia. One hundred eighty-eight disc-shaped specimens of thermopolymerizable PMMA were prepared and randomly allocated to five treatment groups: sterile saline solution (0.85%; control); chlorhexidine digluconate (0.2%); and hydroalcoholic extract of E. uniflora (0.2%, 0.8%, and 1.16%). The specimens were disinfected for 8 hours/day for 30 days. Adherence of microorganisms to the surface, PMMA surface roughness, and color stability were assessed. Inferential statistics were performed with one- and two-way ANOVA/Tukey test, and Kruskal Wallis, Mann-Whitney U, and paired t-tests, at α=0.05. The extract of E. uniflora at 0.2% and 1.16% reduced the microbial load of K. oxytoca, while chlorhexidine digluconate significantly reduced microbial load of all microrganisms. Microbial adherence at day 10 was reduced by all experimental substances (p<0.001). Surface roughness was not affected by the disinfecting substances (p>0.05). Nevertheless, all experimental groups produced unacceptable color change at the end of the disinfection protocol (p<0.001). The non-adherent potential against microorganisms isolated from the oral cavity confirm the potential of use of the hydroalcoholic extract of E. uniflora as a denture disinfectant. Yet, unacceptable color changes may occur, regardless of extract concentration.

Humans , Staphylococcus aureus/drug effects , Candida albicans/drug effects , Plant Extracts/pharmacology , Dentures , Klebsiella oxytoca/drug effects , Eugenia/chemistry , Mouthwashes/pharmacology , Polymethyl Methacrylate
Braz. j. infect. dis ; 23(1): 8-14, Jan.-Feb. 2019. tab, graf
Article in English | LILACS | ID: biblio-1001504


ABSTRACT Introduction: Bacterial tonsillitis is an upper respiratory tract infection that occurs primarily in children and adolescents. Staphylococcus aureus is one of the most frequent pathogens in the etiology of tonsillitis and its relevance is due to its antimicrobial resistance and persistence in the internal tissues of the tonsils. Tonsillectomy is indicated in cases of recurrent tonsillitis after several failures of antibiotic therapy. Material and methods: In this study we evaluated 123 surgically removed tonsils from patients who had history of recurrent tonsillitis. The tonsils were submitted to microbiological analysis for detection of S. aureus. The isolates were identified by PCR for femA gene. Antimicrobial susceptibility of the isolates was determined by disk diffusion tests. All isolates were submitted to PCR to detect mecA and Panton-Valentine leucocidin (PVL) genes. The genetic similarity among all isolates was determined by pulsed field gel electrophoresis. Results: Sixty-one S. aureus isolates were obtained from 50 patients (40.7%) with mean age of 11.7 years. The isolates showed high level resistance to penicillin (83.6%), 9.8% had inducible MLSb phenotype, and 18.0% were considered multidrug resistant (MDR). mecA gene was detected in two isolates and the gene coding for PVL was identified in one isolate. The genetic similarity analysis showed high diversity among the isolates. More than one genetically different isolate was identified from the same patient, and identical isolates were obtained from different patients. Conclusions: MDR isolates colonizing tonsils even without infection, demonstrate persistence of the bacterium and possibility of antimicrobial resistance dissemination and recurrence of infection. A specific clone in patients colonized by S. aureus was not demonstrated.

Humans , Male , Female , Infant , Child, Preschool , Child , Adolescent , Adult , Middle Aged , Young Adult , Staphylococcal Infections/microbiology , Staphylococcus aureus/isolation & purification , Staphylococcus aureus/genetics , Tonsillitis/microbiology , Staphylococcus aureus/drug effects , Tonsillectomy/methods , Tonsillitis/surgery , Polymerase Chain Reaction , Cross-Sectional Studies , Electrophoresis, Gel, Pulsed-Field , Drug Resistance, Multiple, Bacterial/drug effects , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Methicillin-Resistant Staphylococcus aureus/drug effects , Anti-Bacterial Agents/pharmacology
Rev. Soc. Bras. Med. Trop ; 52: e20190095, 2019. tab, graf
Article in English | LILACS | ID: biblio-1013299


Abstract INTRODUCTION Staphylococcus aureus is a major nosocomial pathogen that is associated with high virulence and the rapid development of drug resistance. METHODS We analyzed and compared the antimicrobial resistance, virulence profiles, and molecular epidemiology of 67 S. aureus strains, including 36 methicillin-sensitive (MSSA) and 31 methicillin-resistant (MRSA) strains recovered from a public hospital located in south-eastern Brazil. RESULTS The clones circulating in this hospital presented a great diversity, and the majority of the strains were related to clones responsible for causing worldwide epidemics: these included USA100 (New York/Japan clone), USA300, and USA600. The 31 MRSA (22 SCCmecII and 9 SCCmecIV) and 36 MSSA strains exhibited low resistance against gentamicin and trimethoprim/sulfamethoxazole. No MRSA strain showed resistance to tetracycline. Virulence gene carriage was more diverse and abundant in MSSA than in MRSA. Of the evaluated adhesion-related genes, ebpS was the most prevalent in both MSSA and MRSA strains. The genes bbp and cna showed a strong association with MSSA strains. CONCLUSIONS Our findings reinforce the idea that MSSA and MRSA strains should be carefully monitored, owing to their high pathogenic potential.

Humans , Staphylococcus aureus/drug effects , Staphylococcus aureus/genetics , Methicillin Resistance , Virulence Factors/genetics , Methicillin-Resistant Staphylococcus aureus/genetics , Anti-Bacterial Agents/pharmacology , Staphylococcal Infections/epidemiology , Staphylococcus aureus/isolation & purification , Staphylococcus aureus/classification , Virulence/genetics , Brazil/epidemiology , Microbial Sensitivity Tests , Molecular Epidemiology , Tertiary Care Centers , Hospitals, Public
Braz. arch. biol. technol ; 62: e19180266, 2019. tab, graf
Article in English | LILACS | ID: biblio-1055379


Abstract Phytochemical content of plant extracts can be used effectively to reduce the metal ions to nanoparticles in one-step green synthesis process. In this study, six plant extracts were used for the synthesis of silver nanoparticles (AgNPs). Biologically synthesized AgNPs was characterized using UV-Vis Spectrophotometer, Field Emission Scanning Electron Microscope (FE-SEM), X-ray diffraction (XRD), Energy Dispersive X-ray spectroscopy (EDX) and Fourier Transform Infrared (FTIR) spectroscopy. The individual and combined effects of AgNPs and tetracycline against S. aureus and K. pneumoniae were assessed. Ginger, onion and sidr extracts supported AgNPs formation while arak, garlic and mint extracts failed to convert the silver ions to AgNPs. The present findings revealed significant differences between the tested plant extracts in supporting AgNPs synthesis. AgNPs synthesized by ginger showed the highest individual and combined activity against tested strains followed by AgNPs prepared by sidr then that synthesized by onion. AgNPs significantly enhanced tetracycline activity (p≤0.05) against S. aureus and K. pneumoniae. The results of this study demonstrated that the combination of tetracycline and biologically synthesized AgNPs presented a useful therapeutically method for the treatment of bacterial infection and counterattacking bacterial resistance.

Silver/pharmacology , Staphylococcus aureus/drug effects , Tetracycline/biosynthesis , Plant Extracts/biosynthesis , Klebsiella pneumoniae/drug effects , Spectrometry, X-Ray Emission/instrumentation , X-Ray Diffraction/instrumentation , Spectrophotometers/methods , Spectroscopy, Fourier Transform Infrared/instrumentation
Arch. Health Sci. (Online) ; 25(3): 46-52, 21/12/2018.
Article in Portuguese | LILACS | ID: biblio-1046418


Introdução: Nos últimos anos ocorreu o aumento de casos relacionados com a infecção por Candida spp. e Staphylococcus spp., bem como o aparecimento de cepas resistentes a antibióticos convencionais. A biossíntese de nanopartículas consiste na redução de um íon metálico por compostos de origem natural como metabólitos secundários de plantas e organismos, sendo a forma mais indicada por apresentar menor toxicidade quando comparada à síntese química. Desta forma, a síntese biológica constitui uma alternativa para a obtenção de novos agentes ativos para o tratamento de infecções microbianas. Objetivos: Sintetizar nanopartículas de prata a partir do extrato aquoso de Mikania glomerata Sprengel e avaliar possível atividade microbicida e citotóxica. Material e Métodos: Para a síntese das nanopartículas de prata (AgNPs) foi utilizado um extrato aquoso das folhas de M. glomerata e uma solução de nitrato de prata. As AgNPs sintetizadas foram avaliadas por espectrofotômetro UV-vis e espectrometria de absorção atômica com chama. Além disso, a atividade antimicrobiana foi avaliada contra cepas de Candida albicans e Staphylococcus aureus e atividade citotóxica contra linhagens celulares HeLa e Vero. Resultados: As AgNPs são mais eficientes no combate à linhagem de Candida albicans e Staphylococcus aureus quando comparadas ao extrato puro administrado. Até a concentração de 100 mg/mL do extrato puro não foi observado efeito inibitório em ambos os micro-organismos. Entretanto quando em contato com as AgNPs, a concentração inibitória foi de 0,006 mg/mL e 0,1 mg/mL para S. aureus e C. albicans, respectivamente. O efeito citotóxico nas células se comportou de maneira dose-dependente, apresentando maior potencial citotóxico contra a linhagem celular cancerosa HeLa. Conclusão: As AgNPs sintetizadas apresentaram potencial antimicrobiano contra C. albicans e S. aureus, além de baixa atividade contra células normais, indicando sua confiabilidade para aplicação das AgNPs como forma alternativa de tratamento. Estes resultados são promissores e contribuem para pesquisa relacionada à produção de medicamentos utilizando extrato de plantas e metais.

Introduction: In recent years there has been an increase in cases related to infection by Candidaspp. and Staphylococcus spp., as well as the appearance of strains resistant to conventional antibiotics. Nanoparticle biosynthesis consists of the reduction of a metal ion by compounds of natural origin as secondary metabolites of plants and organisms, being the most indicated form because it presents less toxicity when compared to the chemical synthesis. In this way, the biological synthesis is an alternative to obtain new active agents for the treatment of microbial infections. Objective: Synthesize silver nanoparticles from the aqueous extract of Mikania glomerata Sprengel and evaluate possible microbicidal and cytotoxic activity. Material and Methods: For the synthesis of the silver nanoparticles (AgNPs) an aqueous extract of the leaves of Mikania glomerata plus a solution of silver nitrate was used. AgNPs synthesized was evaluated by UV-vis spectrophotometer and FAAS. Furthermore, antimicrobial activity was evaluated against strains of Candida albicans and Staphylococcus aureus and cytotoxicity activity against HeLa and Vero cell lines. Results: AgNPs are shown to be more efficient in combating Candida albicans and Staphylococcus aureusstrains when compared to the pure administered extract. Up to the concentration of 100 mg/mL of the pure aqueous extract no inhibitory effect was observed on both microorganisms. However when the strains were in contact with AgNPs, the inhibitory concentration was 0.006 mg/mL and 0.1 mg/mL for S. aureus and C. albicans, respectively. The cytotoxic effect on the cells behaves in a dose-dependent manner, presenting greater cytotoxic potential against the HeLa cancer cell line. Conclusion: Thus, these results are promising and contribute to research related to the production of drugs using plant extract and metals. The AgNPs synthesized presented the antimicrobial potential against C. albicans and S. aureus, in addition to low activity against normal cells, indicating their reliability for application of AgNPs as an alternative form of treatment.

Staphylococcus aureus/drug effects , Candida albicans/drug effects , Metal Nanoparticles/therapeutic use , Anti-Infective Agents/therapeutic use
Acta cir. bras ; 33(11): 983-990, Nov. 2018. graf
Article in English | LILACS | ID: biblio-973479


Abstract Purpose: To investigate the efficacy and mechanisms of root tuber of Polygonum ciliinerve (Nakai) ohwi (rPC) which has been used to treat bacterial infection in traditional Chinese medicine. Methods: With the mouse model of Staphylococcus aureus (S. aureus) pneumonia, the phenotype of rPC treated mice, including body weight, mortality, lung slices and bacterial burden were evaluated. Furthermore, inflammatory factors in bronchoalveolar lavage (BAL) were determined by ELISA and the distribution of T cells in lung was assessed by immunofluorescence assay. Results: rPC treatment could dose-dependently reduce weight loss and mortality in S. aureus-infected mice. Upon 10 mg/ml rPC treatment, S. aureus-infected mice showed about 8 grams increase in body weight (P<0.001) and 50% enhancement in mortality. The integrity of lung tissue and bacterial burden were also improved by rPC treatment. Moreover, rPC was found to modulate the immune response in infection. Conclusion: rPC has therapeutic potential for S. aureus infections and pneumonia with immunomodulatory functions.

Animals , Pneumonia, Staphylococcal/prevention & control , Staphylococcus aureus/drug effects , Drugs, Chinese Herbal/pharmacology , Protective Agents/pharmacology , Polygonum/chemistry , Immunomodulation/drug effects , Anti-Bacterial Agents/pharmacology , Pneumonia, Staphylococcal/pathology , Pneumonia, Staphylococcal/drug therapy , Time Factors , Enzyme-Linked Immunosorbent Assay , Bronchoalveolar Lavage Fluid/chemistry , Immunohistochemistry , Colony Count, Microbial , Reproducibility of Results , Interleukin-6/analysis , Tumor Necrosis Factor-alpha/analysis , Treatment Outcome , Chemokine CCL2/analysis , Lung/drug effects , Lung/pathology , Mice, Inbred C57BL
Article in Spanish | LILACS | ID: biblio-1007328


Propolis is a substance manufactured by Apis mellifera and has been widely used in folk medicine due to its high concentration of bioactive compounds. The purpose of the following study was to characterize and evaluate in vitro the antimicrobial properties of propolis on clinical samples and ATCC strains. The chemical characterization of propolis presents a concentration of total polyphenols of 247 ± 9 mg EAG g-1 MS, flavones and flavonols 75± 4 mg EQ g-1 MS, flavanonones and flavanonols 118 ± 11 EP g-1 MS. HPLC-DAD identified apigenin, galangin, phenethyl ester of caffeic acid and pinocembrin, in addition to 16 compounds by HPLC MS/MS. Chilean propolis is a natural antimicrobial, showing effectiveness in strains ATCC Staphylococcus aureus, Candida albicans, Trichophyton rubrum and clinical samples of Staphylococcus aureus unlike Escherichia coli. These results demonstrate the antimicrobial effectiveness of the synergy of compounds present in propolis against different human pathogens.

El propóleos es una substancia fabricada por Apis mellifera y ha sido utilizado ampliamente en la medicina popular debido a su alta concentración de compuestos bioactivos. El propósito del siguiente estudio fue caracterizar y evaluar in vitro las propiedades antimicrobianas del propóleos sobre muestras clínicas y cepas ATCC. La caracterización química de propóleos presenta una concentración de polifenoles totales de 247 ± 9 mg EAG g-1 de MS, flavonas y flavonoles 75 ± 4 mg EQ g-1 de MS, flavanononas y flavanonoles 118 ± 11 EP g-1 de MS. Mediante HPLC-DAD se identificó apigenina, galangina, fenetil éster del ácido cafeico y pinocembrina, además de 16 compuestos mediante HPLC MS/MS. El propóleos chileno es un antimicrobiano natural, observándose efectividad en cepas ATCC Staphylococcus aureus, Candida albicans, Trichophyton rubrum y muestras clínicas de Staphylococcus aureus a diferencia de Escherichia coli. Estos resultados demuestran la efectividad antimicrobiana de la sinergia de compuestos presentes en el propóleos ante diferentes patógenos humanos.

Humans , Propolis/pharmacology , Staphylococcus aureus/drug effects , Candida albicans/drug effects , Escherichia coli/drug effects , Anti-Infective Agents/pharmacology , Pharynx/microbiology , Propolis/chemistry , Trichophyton/drug effects , Flavonoids/analysis , Microbial Sensitivity Tests , Apis mellifica , Chile , Chromatography, High Pressure Liquid , Escherichia coli/drug effects , Gas Chromatography-Mass Spectrometry , Anti-Infective Agents/chemistry , Mouth/microbiology
Braz. j. microbiol ; 49(3): 656-661, July-Sept. 2018. tab, graf
Article in English | LILACS | ID: biblio-951809


Abstract Hamelia patens, is a plant traditionally used to treat a variety of conditions among the Huastec people of Mexico. The objective of this study is to characterize the phenolic content and critically examine the antimicrobial activity of leaf extracts H. patens, obtained by maceration, Soxhlet and percolation, using ethanol as 70% solvent. Phenolic compounds are characterized by liquid chromatography, coupled to a High Resolution Mass Spectrometry, and the antimicrobial activity was studied from the inhibitory effect of each extract for Escherichia coli, Staphylococcus aureus, Salmonella typhi and S. paratyphi, and by the Minimum Bactericidal Concentration, the percentage of activity and the Index of Bacterial Susceptibility of each extract. The phenolic compound identified in different concentrations in the three extracts was epicatechin. The extracts obtained by the three methods had antimicrobial activity, however, there was no significant difference (p < 0.05) between the Minimum Bactericidal Concentration of the extracts obtained by maceration, percolation and Soxhlet. The results of this study contribute to the body of knowledge on the use of extracts in controlling microorganisms with natural antimicrobials.

Phenols/isolation & purification , Phenols/pharmacokinetics , Plant Extracts/isolation & purification , Plant Extracts/pharmacokinetics , Hamelia/chemistry , Chemical Fractionation/methods , Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/pharmacology , Phenols/chemistry , Staphylococcus aureus/drug effects , Plant Extracts/chemistry , Microbial Sensitivity Tests , Escherichia coli/drug effects , Mexico , Anti-Bacterial Agents/chemistry
Rev. Soc. Bras. Med. Trop ; 51(4): 533-536, July-Aug. 2018. tab, graf
Article in English | LILACS | ID: biblio-1041470


Abstract INTRODUCTION This aim of this study was to evaluate the antibacterial activity of fractions and isolates of Maytenus guianensis, a plant species used in Amazonian folk medicine. METHODS A disk diffusion technique was used to investigate the antibacterial potential. RESULTS The hexanic fractions and tingenone B isolate showed inhibitory effects against Staphylococcus aureus and Streptococcus pneumoniae. CONCLUSIONS These results indicate the antibacterial potential of this species and will enable future studies to identify novel therapeutic alternatives from this species.

Staphylococcus aureus/drug effects , Streptococcus pneumoniae , Plant Extracts/pharmacology , Maytenus/chemistry , Escherichia coli/drug effects , Klebsiella pneumoniae/drug effects , Anti-Bacterial Agents/pharmacology , Disk Diffusion Antimicrobial Tests , Anti-Bacterial Agents/isolation & purification
Rev. salud pública Parag ; 8(2): [P28-P33], Jul - Dic 2018.
Article in Spanish | LILACS | ID: biblio-980586


Introducción: El Staphylococcus Aureus constituye un agente etiológico frecuente de intoxicaciones alimentarias y se encuentra asociado a diversos alimentos. Objetivo: Describir la frecuencia de portación de Staphylococcus Aureus en manipuladores de alimentos de restaurantes de Asunción durante el 2017. Metodología: Se realizó un estudio observacional, prospectivo, descriptivo de corte transversal a manipuladores de alimentos de restaurantes de Asunción durante los meses de mayo a junio del 2017. Se realizaron tres hisopados nasales a cada uno de los 30 manipuladores de alimentos para determinar si la portación era intermitente, permanente u ocasional. Al mismo tiempo fueron realizadas encuestas donde se midieron variables demográficas. Resultados: La prevalencia de portación de Staphylococcus Aureus fue del 33,3 % (10), siendo el 40% (4) esporádica e intermitente y el 20% (2) permanente. En cuanto a las características demográficas de los manipuladores,el 56,66% (17) fueron del sexo masculino, eran solteros 43,33% (13) y el 50% (15) contaban con estudios secundarios completos. El promedio de edad de 29 de los manipuladores fue de 39,5 años con un rango comprendido entre 18 y 85 años. El 23,33% (7) utilizaban guantes a la hora de manipular los alimentos. Además, se pudo observar que el 26,66% (8) utilizaba gorros. Llamó la atención que el 30% (9) de los encuestados no presentaban uñas limpias durante la manipulación. Palabras clave: Staphylococcus Aureus; manipuladores; alimentos.

Introduction: Staphylococcus Aureus is a frequent etiologic agent of food poisoning and is associated with various foods. Objective : To describe the frequency of Staphylococcus Aureus in food handlers of restaurants in Asunción during 2017. Methodology: An observational, prospective, descriptive, cross-sectional study was carried out on food handlers in restaurants in Asuncion during the months of May to June 2017. Three nasal swabs were made to each of the 30 food handlers to determine if the carriage was intermittent, permanent or occasional. At thesame time, surveys were carried out where demographic variables were measured. Results: The prevalence of carrying Staphylococcus Aureus was 33.3% (10), being 40% (4) sporadic and intermittent and 20% (2) permanent. Regarding the demographic characteristics of the manipulators, 56.66% (17) were male, were single 43.33% (13) and 50% (15) had complete secondary education. The average age of 29 of the manipulators was 39.5 years with ranger between 18 and 85 years. 23.33% (7) used gloves when handling food. In addition, it was observed that 26.66% (8) used caps. It was noted that 30% (9) of theres pondents did not have clean nails during handling. Keywords: Staphylococcus Aureus; manipulators; food.

Humans , Male , Female , Adolescent , Adult , Middle Aged , Aged , Aged, 80 and over , Staphylococcal Infections/epidemiology , Staphylococcus aureus/isolation & purification , Food Handling , Paraguay/epidemiology , Staphylococcal Infections/transmission , Staphylococcus aureus/drug effects , Drug Resistance, Microbial , Hygiene , Prevalence , Cross-Sectional Studies , Prospective Studies
Braz. j. microbiol ; 49(2): 310-319, Apr.-June 2018. tab, graf
Article in English | LILACS | ID: biblio-889225


Abstract The aim of this study was evaluated the biofilm formation by Staphylococcus aureus 4E and Salmonella spp. under mono and dual-species biofilms, onto stainless steel 316 (SS) and polypropylene B (PP), and their sensitivity to cetrimonium bromide, peracetic acid and sodium hypochlorite. The biofilms were developed by immersion of the surfaces in TSB by 10 d at 37 °C. The results showed that in monospecies biofilms the type of surface not affected the cellular density (p > 0.05). However, in dual-species biofilms on PP the adhesion of Salmonella spp. was favored, 7.61 ± 0.13 Log10 CFU/cm2, compared with monospecies biofilms onto the same surface, 5.91 ± 0.44 Log10 CFU/cm2 (p < 0.05). The mono and dual-species biofilms were subjected to disinfection treatments; and the most effective disinfectant was peracetic acid (3500 ppm), reducing by more than 5 Log10 CFU/cm2, while the least effective was cetrimonium bromide. In addition, S. aureus 4E and Salmonella spp. were more resistant to the disinfectants in mono than in dual-species biofilms (p < 0.05). Therefore, the interspecies interactions between S. aureus 4E and Salmonella spp. had a negative effect on the antimicrobial resistance of each microorganism, compared with the monospecies biofilms.

Biofilms/drug effects , Cetrimonium Compounds/pharmacology , Disinfectants/pharmacology , Peracetic Acid/pharmacology , Salmonella/drug effects , Sodium Hypochlorite/pharmacology , Staphylococcus aureus/drug effects , Bacterial Adhesion/drug effects , Biofilms/growth & development , Colony Count, Microbial , Culture Media/chemistry , Environmental Microbiology , Microbial Interactions , Microbial Viability/drug effects , Polypropylenes , Salmonella/growth & development , Stainless Steel , Staphylococcus aureus/growth & development , Temperature , Time
Arq. gastroenterol ; 55(1): 23-27, Apr.-Mar. 2018. tab
Article in English | LILACS | ID: biblio-888233


ABSTRACT BACKGROUND: Spontaneous bacterial peritonitis is a serious complication in cirrhotic patients, and changes in the microbiological characteristics reported in the last years are impacting the choice of antibiotic used for treatment. OBJECTIVE: The aim of the present study is to evaluate the changes in the epidemiology and bacterial resistance of the germs causing spontaneous bacterial peritonitis over three different periods over 17 years. METHODS: All cirrhotic patients with spontaneous bacterial peritonitis and positive culture of ascites fluid were retrospectively studied in a reference Hospital in Southern Brazil. Three periods were ramdomly evaluated: 1997-1998, 2002-2003 and 2014-2015. The most frequent infecting organisms and the sensitivity in vitro to antibiotics were registered. RESULTS: In the first period (1997-1998) there were 33 cases, the most common were: E. coli in 13 (36.11%), Staphylococcus coagulase-negative in 6 (16.66%), K. pneumoniae in 5 (13.88%), S. aureus in 4 (11.11%) and S. faecalis in 3 (8.33%). In the second period (2002-2003), there were 43 cases, the most frequent were: Staphylococus coagulase-negative in 16 (35.55%), S. aureus in 8 (17.77%), E. coli in 7 (15.55%) and K. pneumoniae in 3 (6.66%). In the third period (2014-2015) there were 58 cases (seven with two bacteria), the most frequent were: E. coli in 15 (23.1%), S. viridans in 12 (18.5%), K. pneumoniae in 10 (15.4%) and E. faecium 5 (7.7%). No one was using antibiotic prophylaxis. Considering all staphylococci, the prevalence increased to rates of the order of 50% in the second period, with a reduction in the third period evaluated. Likewise, the prevalence of resistant E. coli increased, reaching 14%. CONCLUSION: There was a modification of the bacterial population causing spontaneous bacterial peritonitis, with high frequency of gram-positive organisms, as well as an increase in the resistance to the traditionally recommended antibiotics. This study suggests a probable imminent inclusion of a drug against gram-positive organisms in the empiric treatment of spontaneous bacterial peritonitis.

RESUMO CONTEXTO: A peritonite bacteriana espontânea é uma complicação séria em pacientes cirróticos e as alterações nas características microbiológicas relatadas nos últimos anos podem afetar a escolha do antibiótico utilizado no tratamento. OBJETIVO: Os objetivos do presente estudo são avaliar as mudanças na epidemiologia e perfil de resistência bacteriana dos germes causadores de peritonite bacteriana espontânea em três períodos diferentes ao longo de 17 anos. MÉTODOS: Todos os pacientes cirróticos com peritonite bacteriana espontânea e cultura positiva de fluido ascítico foram estudados retrospectivamente em um hospital de referência no Sul do Brasil. Foram avaliados três diferentes períodos selecionados de forma randômica: 1997-1998, 2002-2003 e 2014-2015. Os organismos infecciosos mais frequentes e a sensibilidade in vitro a antibióticos foram registados. RESULTADOS: No primeiro período (1997-1998) houve 33 casos; os mais comuns foram: E. coli em 13 (36,1%), Staphylococcus coagulase-negativo em 6 (16,7%), K. pneumoniae em 5 (13,9%), S. aureus em 4 (11,1%) e S. faecalis em 3 (8,3%). No segundo período (2002-2003), houve 43 casos, os mais frequentes foram: Staphylococus coagulase-negativo em 16 (35,5%), S. aureus em 8 (17,8%), E. coli em 7 (15,5%) e K. pneumoniae em 3 (6,7%). No terceiro período (2014-2015), houve 58 casos (sete com duas bactérias), os mais frequentes foram: E. coli em 15 (23,1%), S. viridans em 12 (18,5%), K. pneumoniae em 10 (15,4%) e E. faecium 5 (7,7%). Nenhum paciente estava usando profilaxia antibiótica. Quando considerados todos os estafilococos, a prevalência aumentou para taxas da ordem de 50% no segundo período, apresentando redução no terceiro período avaliado. Do mesmo modo, a prevalência de E coli resistente aumentou, chegando a 14%. CONCLUSÃO: Houve modificação da população bacteriana causadora de peritonite bacteriana espontânea, com alta frequência de organismos gram-positivos, bem como aumento da resistência aos antibióticos tradicionalmente recomendados. Este estudo sugere uma provável inclusão iminente de um medicamento contra organismos gram-positivos no tratamento empírico da peritonite bacteriana espontânea.

Humans , Peritonitis/microbiology , Gram-Positive Bacterial Infections/complications , Drug Resistance, Bacterial/drug effects , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Anti-Bacterial Agents/pharmacology , Peritonitis/drug therapy , Staphylococcus aureus/isolation & purification , Staphylococcus aureus/drug effects , Time Factors , Brazil/epidemiology , Microbial Sensitivity Tests , Retrospective Studies , Gram-Positive Bacterial Infections/drug therapy , Gram-Positive Bacterial Infections/epidemiology , Antibiotic Prophylaxis , Escherichia coli/isolation & purification , Escherichia coli/drug effects , Escherichia coli Infections/drug therapy , Escherichia coli Infections/epidemiology , Gram-Negative Bacteria/isolation & purification , Gram-Positive Bacteria/isolation & purification , Liver Cirrhosis/complications , Anti-Bacterial Agents/therapeutic use
Braz. j. infect. dis ; 22(2): 99-105, Mar.-Apr. 2018. tab, graf
Article in English | LILACS | ID: biblio-951629


ABSTRACT Introduction: Staphylococcus spp. - both S. aureus, including methicillin-resistant strains (MRSA) and coagulase negative staphylococci (CoNS) - are relevant agents of healthcare-associated infections. Therefore, the rapid recognition of MRSA and methicillin-resistant CoNS from blood stream infections is critically important for patient management. It is worth noting that inappropriate empiric therapy has been associated with higher in-hospital mortality. Material and methods: In this study we evaluated a multiplex polymerase chain reaction (multiplex PCR) standardized to detect Staphylococcus spp., S. aureus, and mecA gene-encoded oxacillin resistance directly from blood culture bottles. A total of 371 blood cultures with Gram-positive microorganisms confirmed by Gram-stain were analyzed. Results from multiplex PCR were compared to phenotypic characterization of isolates. Results: Staphylococcus aureus was detected in 85 (23.0%) blood cultures and CoNS in 286 (77.0%). There was 100% agreement between phenotypic and multiplex PCR identification. Forty-three (50.6%) of the 85 S. aureus carried the mecA gene and among the 286 CoNS, 225 (78.7%) were positive for the mecA gene. Conclusions: The multiplex PCR assay developed here was found to be sensitive, specific, rapid, and showed good agreement with the phenotypic results besides being less expensive. This PCR method could be used in clinical laboratories for rapid identification and initiation of specific and effective treatment, reducing patient mortality and morbidity. Furthermore, this method may reduce misuse of antimicrobial classes that are more expensive and toxic, thus contributing to the selection of antibiotic-resistant Staphylococcus spp.

Humans , Bacterial Proteins/genetics , Blood/microbiology , Bacteremia/diagnosis , Penicillin-Binding Proteins/genetics , Methicillin-Resistant Staphylococcus aureus/genetics , Multiplex Polymerase Chain Reaction , Oxacillin/pharmacology , Staphylococcal Infections/diagnosis , Staphylococcus aureus/isolation & purification , Staphylococcus aureus/drug effects , Bacterial Proteins/isolation & purification , DNA, Bacterial/genetics , Bacteremia/microbiology , Penicillin-Binding Proteins/isolation & purification , Blood Culture , Anti-Bacterial Agents/pharmacology
An. acad. bras. ciênc ; 90(1): 73-84, Mar. 2018. tab
Article in English | LILACS | ID: biblio-886885


ABSTRACT The adhesion ability of bacteria to abiotic surfaces has important implications in food industries, because these organisms can survive for long periods through the biofilm formation. They can be transferred from one place to another in the industry causing contamination of the food processing environment. In this study, the antibacterial and antibiofilm activities of the antimicrobial peptide P34, characterized as a bacteriocin-like substance (BLS P34) were tested against planktonic and sessile cells of Staphylococcus aureus and Enterococcus faecalis isolated from foods. The BLS P34 showed inhibitory effect against all planktonic cells of E. faecalis. The inhibition of biofilm formation and the eradication of pre-formed biofilm were evaluated with the crystal violet assay and with the reduction of 3-bromide [4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium. The BLS P34 promoted a reduction of percentage of adhered microbial cells on the surface, not being able to perform the complete elimination of biofilm formation. The metabolic activity of S. aureus biofilms decreased considerably between 41-95%. However, E. faecalis cells showed up metabolically stimulated. The BLS P34 has the potential antibiofilm for the species S. aureus. Studies suggest more detailed approaches to a better understanding of the interactions between the antimicrobial and bacterial cells within the biofilm structure.

Animals , Oligopeptides/pharmacology , Staphylococcus aureus/drug effects , Bacteriocins/pharmacology , Enterococcus faecalis/drug effects , Biofilms/drug effects , Anti-Bacterial Agents/pharmacology , Bacillus/isolation & purification , Bacillus/metabolism , Bacteriocins/isolation & purification , Bacterial Adhesion/drug effects , Microbial Sensitivity Tests , Analysis of Variance
Electron. j. biotechnol ; 32: 41-46, Mar. 2018. tab, ilus, graf
Article in English | LILACS | ID: biblio-1022633


Background: In view of the current low efficacy of bacterial infection treatment the common trend towards searching for antibiotic systems exhibiting synergistic action is well justified. Among carbapenem analogues a particularly interesting option is provided by combinations of clavulanic acid with meropenem, which have proven to be especially effective. Results: Determination of the minimal inhibitory concentration (MIC) along with the method based on flow cytometry constitutes an important tool in the identification of bacterial sensitivity to active substances. Within this study the inhibitory effect of doripenem, clavulanic acid and the doripenem-clavulanate acid system was analyzed in relation to such bacteria as Salmonella enteritidis, Salmonella typhimurium, Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa, Proteus vulgaris, Clostridium butyricum and Clostridium pasteurianum, Acinetobacter baumannii, Enterobacter aerogenes. The lowest MIC, amounting to 0.03 µg/mL, was observed for the doripenem-clavulanate acid system in the case of E. coli ATCC 25922. In turn, the lowest MIC for doripenem applied alone was recorded for K. pneumoniae ATCC 31488, for which it was 0.1 µg/mL. The strain which proved to be most resistant both to doripenem and the doripenem-clavulanate acid system, was A. baumannii, with MIC of 32 µg/mL (clinical isolate) and 16 µg/mL (reference strain). Cytometric analysis for P. aeruginosa ATCC 27853 and S. aureus ATCC 25923 showed changes in cells following exposure to limiting concentrations of the active substance. Conclusions: Analysis of MIC supplies important information concerning microbial sensitivity to active substances, mainly in terms of limiting concentrations causing mortality or vitality of the tested species, which is essential when selecting appropriate antibiotic therapy.

Bacteria/drug effects , Clavulanic Acids/pharmacology , /pharmacology , Anti-Bacterial Agents/pharmacology , Pseudomonas aeruginosa/drug effects , Salmonella/drug effects , Staphylococcus aureus/drug effects , Microbial Sensitivity Tests , Clostridium/drug effects , Drug Interactions , Flow Cytometry , Klebsiella pneumoniae/drug effects
Rev. bras. anestesiol ; 68(1): 69-74, Jan.-Feb. 2018. tab, graf
Article in English | LILACS | ID: biblio-897807


Abstract Introduction Propofol and Ephedrine are commonly used during anesthesia maintenance, the former as a hypnotic agent and the later as a vasopressor. The addition of propofol to ephedrine or administration of ephedrine before propofol injection is useful for decreasing or preventing propofol related hemodynamic changes and vascular pain. This in vitro study evaluated the antibacterial effect on common hospital-acquired infection pathogens of ephedrine alone or combined with propofol. Material and method The study was performed in two stages. In the first, the Minimum Inhibitory Concentration of propofol and ephedrine alone and combined was calculated for Escherichia coli, Enterococcus faecium, Staphylococcus aureus, Pseudomonas aeruginosa, and a clinical isolate of Acinetobacter spp. at 0, 6, 12 and 24 h, using the microdilution method. In the second stage, the same drugs and combination were used to determine their effect on bacterial growth. Bacterial solutions were prepared at 0.5 MacFarland in sterile 0.9% physiological saline and diluted at 1/100 concentration. Colony numbers were measured as colony forming units.mL-1 at 0, 2, 4, 6, 8, 10 and 12th hours. Results Ephedrine either alone or combined with propofol did not have an antimicrobial effect on Escherichia coli, Enterococcus faecium, or Pseudomonas aeruginosa and this was similar to propofol. However, ephedrine alone and combined with propofol was found to have an antimicrobial effect on Staphylococcus aureus and Acinetobacter species at 512 mcg.mL-1 concentration and significantly decreased bacterial growth rate. Conclusion Ephedrine has an antimicrobial activity on Staphylococcus aureus and Acinetobacter species which were frequently encountered pathogens as a cause of nosocomial infections.

Resumo Introdução Propofol e efedrina são fármacos comumente usados durante a manutenção da anestesia, o primeiro como agente hipnótico e o segundo como vasopressor. A adição de propofol à efedrina ou a administração de efedrina antes da injeção de propofol é útil para diminuir ou prevenir alterações hemodinâmicas e dor vascular relacionadas ao propofol. Este estudo in vitro avaliou o efeito antibacteriano de efedrina, isolada ou em combinação com propofol, em patógenos comuns implicados em infecção hospitalar. Material e método O estudo foi feito em duas etapas. Na primeira, a concentração inibitória mínima (CIM) de propofol e de efedrina isolada e em combinação foi calculada para Escherichia coli, Enterococcus faecium, Staphylococcus aureus, Pseudomonas aeruginosa e um isolado clínico de Acinetobacter spp às 0, 6, 12 e 24 horas, com o método de microdiluição. Na segunda etapa, o mesmo fármaco e sua combinação foram usados para determinar seus efeitos no crescimento bacteriano. As soluções bacterianas foram preparadas em soro fisiológico a 0,9% em 0,5 McFarland e diluídas a uma concentração de 1/100. Os números das colônias foram medidos como ufc.mL-1 às 0, 2, 4, 6, 8, 10 e 12 horas. Resultados Efedrina isolada ou em combinação com propofol não apresentou efeito antimicrobiano sobre E. coli, E. faecium ou P. aeruginosa, um resultado semelhante ao de propofol. Porém, efedrina isolada e em combinação com propofol apresentou efeito antimicrobiano sobre Staphylococcus aureus e Acinetobacter spp, em concentração de 512 mcg.mL-1, e redução significativa da taxa de crescimento bacteriano. Conclusão Efedrina tem atividade antimicrobiana em S. aureus e Acinetobacter spp, patógenos frequentemente identificados como causa de infecções nosocomiais.

Pseudomonas aeruginosa/drug effects , Staphylococcus aureus/drug effects , Vasoconstrictor Agents/pharmacology , Acinetobacter/drug effects , Propofol/pharmacology , Enterococcus faecium/drug effects , Ephedrine/pharmacology , Hypnotics and Sedatives/pharmacology , Vasoconstrictor Agents/administration & dosage , Microbial Sensitivity Tests , Propofol/administration & dosage , Ephedrine/administration & dosage , Escherichia coli/drug effects , Hypnotics and Sedatives/administration & dosage , Anti-Bacterial Agents
Arq. bras. oftalmol ; 80(5): 300-303, Sept.-Oct. 2017. tab
Article in English | LILACS | ID: biblio-888140


ABSTRACT Purpose: To compare the aqueous humor (AH) concentrations of moxifloxacin 0.5% and gatifloxacin 0.3% solutions alone or when treatment was combined with steroids, and to correlate these concentrations with the minimum inhibitory concentrations (MIC) for the most common endophthalmitis-causing organisms. Methods: Patients undergoing phacoemulsification were enrolled to receive one drop of one of the following solutions: moxifloxacin (G1), moxifloxacin + dexamethasone (G2), gatifloxacin (G3), or gatifloxacin + c (G4), every 15 min, 1h before surgery. AH samples were collected before surgery and analyzed using HPLC-tandem mass spectrometry. Results: The mean antibiotic concentrations in the AH were: G1= 1280.8 ng/mL; G2= 1644.3 ng/mL; G3= 433.7 ng/mL; and G4= 308.1 ng/mL. The mean concentrations statistically differed between G1 and G2 (p=0.01), and G3 and G4 (p=0.008). All samples achieved the MIC for Staphylococcus epidermidis; 100% of the samples from G1 and G2, and 97% from G3 and G4 reached the MIC for fluoroquinolone-sensitive Staphylococcus aureus; 100% of the samples from G1 and G2, 88% from G3, and 72% from G4 reached the MIC for enterococci (p<0.001); and 100% of samples from G1 and G2, 59% from G3, and 36% from G4 reached the MIC for Streptococcus pneumoniae (p<0.001). For fluoroquinolone-resistant S. aureus, 23% from G1, 44% from G2, and no samples from G3 or G4 achieved the MIC (p<0.001). Conclusions: Moxifloxacin + dexamethasone demonstrated a higher concen­tration in the AH than the moxifloxacin alone. Gatifloxacin + steroids demonstrated less penetration into the anterior chamber than gatifloxacin alone. Moxifloxacin was superior to gatifloxacin considering the MIC for enterococci, S. pneumoniae, and fluoroquinolone-resistant S. aureus.

RESUMO Objetivos: Comparar a concentração no humor aquoso entre as soluções de moxifloxacina 0,5% e gatifloxacina 0,3% sozinhas ou combinadas com corticosteroides, e correlacionar a concentração com a concentração inibitória mínima (MIC) para os agentes microbianos mais comumente relacionados a endoftalmites. Métodos: Pacientes que seriam submetidos a cirurgia de catarata foram selecionados para receber 1 gota a cada 15 min, 1 hora antes do procedimento de uma das seguintes soluções: moxifloxacina (G1), moxifloxacina + dexametasona (G2), gatifloxacina (G3) ou gatifloxacina + prednisolona (G4). Amostras do humor aquoso foram coletadas antes do início da cirurgia. Espectrofotometria de massa por HPLC determinou a concentração do antibiótico nas amostras. Resultados: A concentração media de antibiótico nas amostras foram: G1= 1280,8 ng/mL; G2= 1644,3 ng/mL; G3= 433,7 ng/mL; G4= 308,1 ng/mL. Concentração média entre G1 e 2 (p=0,01), e G3 e 4 (p=0,008). Todas as amostras alcançaram MIC para S. epidermidis; 100% das amostras do G1 e 2, e 97% do G3 e 4 atingiram o MIC para S. aureus fluoroquinolona-sensível; 100% das amostras do G1 e 2, 88% do G3 e 72% do G4 atingiram o MIC para Enterococci (p<0,001); e 100% das amostras do G1 e 2, 59% do G3 e 36% do G4 atingiram o MIC para S. pneumoniae (p<0,001). Para o S. aureus resistente a fluoroquinolona, 23% do G1, 44% do G2, e nenhuma das amostras G3 e 4 atingiram o MIC (p<0,001). Conclusão: Moxifloxacina + dexamethasona demonstrou maior concentração no humor aquoso comparado com a moxifloxacina sozinha. Gatifloxacina + esteróide demonstrou menor penetração na câmara anterior comparado a solução de ga­ti­floxacin sem corticóide. A moxifloxacina foi superior a gatifloxacina considerando o MIC para Enterococci, S. pneumoniae e S. aureus fluorquinolona resistente.

Humans , Male , Female , Middle Aged , Aged , Aged, 80 and over , Aqueous Humor/chemistry , Steroids/analysis , Fluoroquinolones/analysis , Anti-Bacterial Agents/analysis , Reference Values , Staphylococcus aureus/drug effects , Streptococcus pneumoniae/isolation & purification , Microbial Sensitivity Tests , Chromatography, High Pressure Liquid , Enterococcus/isolation & purification , Enterococcus/drug effects , Fluoroquinolones/pharmacology , Tandem Mass Spectrometry , Moxifloxacin , Gatifloxacin , Anti-Bacterial Agents/pharmacology