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Arq. Inst. Biol ; 87: e0142020, 2020. tab
Article in English | LILACS, VETINDEX | ID: biblio-1130108


The genus Streptomyces is associated with the ability to produce and excrete a variety of bioactive compounds, such as antibiotic, antifungal and antiviral. Biological active polyketide and peptide compounds with applications in medicine, agriculture and biochemical research are synthesized by PKS-I and NRPS genes. The evaluation of the presence of these genes associated with the biosynthesis of secondary metabolites in different phytopathogenic Streptomyces strains were performed using degenerated primers. The positive signal was observed in 58/63 Streptomyces strains for NRPS gene, 43/63 for PKS-I, and for PKS-II all the 63 strains showed positive signal of amplification. These strains also were tested with double layer agar-well technique against bacterial with clinical importance, and it was possible to observe the Streptomyces spp. strains were able to inhibit the growth of 14, 20, 13 and 3 isolates Gram-positive and Gram-negative bacteria, Staphylococcus aureus (ATCC 25923), Bacillus cereus (ATCC 14579), Pseudomonas aeruginosa (ATCC 27853) and Escherichia coli (ATCC 11775) respectively. The Streptomyces sp. strains IBSBF 2019 and IBSBF 2397 showed antibacterial activity against all four bacteria-target tested.(AU)

O gênero Streptomyces apresenta alta capacidade de produzir e excretar uma grande variedade de compostos biologicamente ativos, como antibióticos, antifúngicos e antivirais. Compostos biologicamente ativos de policetídeos e peptídeos com aplicações na medicina, agricultura e pesquisas bioquímicas são sintetizados pelos genes PKS-I e NRPS. A avaliação da presença desses genes associados à biossíntese de metabólitos secundários em diferentes linhagens de Streptomyces fitopatogênicas foi realizada através do uso de primers degenerados. O sinal positivo foi observado em 58/63 linhagens de Streptomyces para o gene NRPS, 43/63 para o gene PKS-I e, para o gene PKS-II, todas as 63 linhagens apesentaram o sinal positivo de amplificação. Essas linhagens também foram testadas através da técnica de dupla camada contra bactérias de importância clínica e foi possível observar que as linhagens de Streptomyces spp. foram capazes de inibir o crescimento de 14, 20, 13 e 3 isolados de bactérias Gram-positivas e Gram-negativas, Staphylococcus aureus (ATCC 25923), Bacillus cereus (ATCC 14579), Pseudomonas aeruginosa (ATCC 27853) e Escherichia coli (ATCC 11775), respectivamente. As linhagens de Streptomyces sp. ISBSF 2019 e 2397 apresentaram atividade antibacteriana contra todas as bactérias-alvo testadas.(AU)

Pseudomonas aeruginosa/growth & development , Staphylococcus aureus/growth & development , Streptomyces/metabolism , Bacillus cereus/growth & development , Escherichia coli/growth & development , Anti-Bacterial Agents/metabolism , Peptide Synthases/genetics , Streptomyces/genetics , Gene Amplification , Polymerase Chain Reaction , Sequence Analysis, DNA , DNA Primers , Polyketide Synthases/genetics , Anti-Bacterial Agents/pharmacology
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
Einstein (Säo Paulo) ; 14(2): 226-230, tab, graf
Article in English | LILACS | ID: lil-788037


ABSTRACT Objective To compare sterility and microbial (bacteria and fungi) load in the outer part of hyperbaric bupivacaine (Neocaína®) in ampoule and bupivacaine in vial, in conventional and sterile pack formulations. Methods The sterile packs were divided into two groups: G1 (n=16) with ampoules and G2 (n=16) with vials. Conventional formulations were divided into two groups, being G3 (n=16) with ampoules and G4 (n=16) with vials. The ampoules and vials were opened and had their content drawn. The empty bottles were then placed in sterile plastic bags and sent for analysis of microbial load (bacteria and fungi) and sterility testing. Data were analyzed using the χ2 test with Yates correction, and 95% confidence interval. Results G1 and G2 showed no bacterial growth when compared to conventional groups (p<0.001). The most common agent in conventional microbiological samples was Staphylococcus aureus. There was no fungal growth in both groups. Conclusion The use of (sterile pack) reduces the microbial load of bottles, and would decrease the chance of exposure to potential contamination of the anesthetic solution.

RESUMO Objetivo Comparar a esterilidade e a carga microbiana (bactérias e fungos) da parte externa dos frascos de envasamento de bupivacaína hiperbárica (Neocaína®) em ampola e bupivacaína em frasco-ampola das apresentações convencional e estéril (sterile pack). Métodos As apresentações estéreis (sterile pack) foram distribuídas em dois grupos, sendo que o G1 (n=16) continha as ampolas e o G2 (n=16), os frascos-ampola. As apresentações convencionais foram distribuídas em dois grupos, a saber G3 (n=16) com as ampolas e G4 (n=16) com os frascos-ampola. As ampolas e os frascos-ampolas eram abertos e tinham seu conteúdo aspirado. Os frascos vazios eram, então, acondicionados em sacos plásticos estéreis e enviados para análise quanto à carga microbiana (bactérias e fungos), bem como para o teste de esterilidade. Os dados foram analisados por meio do teste χ2 com correção Yates com intervalo de confiança de 95%. Resultados Os grupos G1 e G2 não apresentaram crescimento bacteriano quando comparado aos grupos convencionais (p<0,001). O microbiano mais comum nas amostras convencionais foi o Staphylococcus aureus. Não houve crescimento de fungos em nenhum dos grupos. Conclusão O uso de embalagens estéreis (sterile pack) diminui a carga microbiana dos frascos de envasamentos, o que diminuiria a chance de exposição a uma potencial contaminação da solução anestésica.

Bupivacaine , Sterilization/methods , Drug Contamination/prevention & control , Equipment Contamination/prevention & control , Drug Packaging/methods , Anesthetics, Local , Staphylococcus aureus/growth & development , Bacillus/growth & development , Time Factors , Colony Count, Microbial , Reproducibility of Results , Risk Factors , Equipment and Supplies/microbiology , Micrococcus/growth & development
Arq. bras. oftalmol ; 77(6): 351-354, Nov-Dec/2014. tab, graf
Article in English | LILACS | ID: lil-735809


Purpose: To study the aerobic bacterial microbiota of the conjunctiva in diabetic patients with regard to the management of diabetes, assessed using glycated hemoglobin levels. Methods: A cross-sectional study was conducted using conjunctival smears of diabetic patients from both sexes and with different ages, residing in two different Brazilian cities (Sorocaba and Rio Branco). A control group of non-diabetic patients was also included. The diabetic patients were considered to have controlled diabetes when their glycated hemoglobin level was ≤7% and blood glucose level was ≤126 mg/dL. Patients with non-controlled diabetes were those with glycated hemoglobin levels >7% and blood glucose levels >126 mg/dL. The samples obtained were inoculated in Brain-Heart Infusion broth and in culture media for aerobic bacteria (blood and chocolate agars); bacterial growth was evaluated in a microbiology laboratory. Results: A total of 120 eyes of 120 patients were included in the present study. The percentage of cultures in which bacterial growth was observed was greater in diabetic patients, although the difference was not statistically significant (p=0.103). There was a greater trend toward bacterial growth in the conjunctiva of diabetic patients with altered fasting blood glucose. There was no difference in the frequency of bacterial growth on the conjunctiva between diabetic patients with normal or altered glycated hemoglobin levels. In Sorocaba, conjunctival bacterial growth was similar to that observed in Rio Branco. The microorganism most frequently detected in the present study was Staphylococcus epidermidis, followed by Staphylococcus aureus, Proteus mirabilis, and Escherichia coli. Conclusion: There was no difference between diabetic patients with normal or altered glycated hemoglobin levels. The microorganisms found were similar to those found in studies investigating the conjunctival bacterial flora of diabetic and non-diabetic ...

Objetivo: Estudar a microbiota conjuntival bacteriana aeróbica dos pacientes diabéticos em relação ao controle glicêmico, verificado através da hemoglobina glicada, em duas cidades distintas. Métodos: Foi realizado um estudo transversal utilizando raspados de conjuntiva de indivíduos diabéticos de ambos os sexos e idades variáveis de duas cidades: Sorocaba e Rio Branco. O grupo controle foi constituído de pacientes não diabéticos. A amostra foi constituída de pacientes diabéticos que foram considerados controlados com hemoglobina glicada ≤7% e glicemia de jejum ≤126 mg/dl e não controlados com hemoglobina glicada >7% e glicemia de jejum >126 mg/dl. O material obtido foi semeado em meio líquido Brain Heart Infusion (BHI) e em meios de cultivo para bactérias aeróbicas (ágar sangue e ágar chocolate). O crescimento bacteriano foi avaliado em laboratório de microbiologia. Resultados: Foram incluídos 120 olhos de 120 pacientes. A porcentagem de culturas nas quais houve crescimento bacteriano foi maior em pacientes diabéticos, sendo a diferença não estatisticamente significante (p=0,103). Não houve diferença entre o crescimento bacteriano em pacientes com hemoglobina glicada normal e alterada. Houve uma tendência maior de crescimento bacteriano em conjuntivas de pacientes diabéticos com glicemias de jejum elevada. Em Sorocaba houve crescimento bacteriano conjuntival semelhante a Rio Branco. O microrganismo mais frequente encontrado neste estudo foi Staphylococcus epidermidis, seguido de Staphylococcus aureus, Proteus mirabilis e Escherichia coli. Conclusões: Não ocorreu diferença entre pacientes diabéticos com hemoglobina glicada normal e alterada. Os microrganismos encontrados foram semelhantes aos estudos da flora bacteriana de conjuntivas normais e de diabéticos. .

Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Bacteria, Aerobic/growth & development , Conjunctiva/microbiology , Diabetes Mellitus/microbiology , Glycated Hemoglobin A/analysis , Microbiota , Age Distribution , Age Factors , Brazil , Case-Control Studies , Colony Count, Microbial , Cross-Sectional Studies , Diabetes Mellitus/blood , Escherichia coli/growth & development , Glycemic Index , Proteus mirabilis/growth & development , Sex Factors , Staphylococcus aureus/growth & development , Staphylococcus epidermidis/growth & development
J. appl. oral sci ; 22(5): 442-449, Sep-Oct/2014. tab, graf
Article in English | LILACS, BBO | ID: lil-729843


The adhesion of biofilm on dental prostheses is a prerequisite for the occurrence of oral diseases. Objective: To assess the antimicrobial activity and the mechanical properties of an acrylic resin embedded with nanostructured silver vanadate (β-AgVO3). Material and Methods: The minimum inhibitory concentration (MIC) of β-AgVO3 was studied in relation to the species Staphylococcus aureus ATCC 25923, Streptococcus mutans ATCC 25175, Pseudomonas aeruginosa ATCC 27853, and Candida albicans ATCC 10231. The halo zone of inhibition method was performed in triplicate to determine the inhibitory effect of the modified self-curing acrylic resin Dencor Lay - Clássico®. The surface hardness and compressive strength were examined. The specimens were prepared according to the percentage of β-AgVO3 (0%-control, 0.5%, 1%, 2.5%, 5%, and 10%), with a sample size of 9x2 mm for surface hardness and antimicrobial activity tests, and 8x4 mm for the compression test. The values of the microbiologic analysis were compared and evaluated using the Kruskal-Wallis test (α=0.05); the mechanical analysis used the Shapiro-Wilk's tests, Levene's test, ANOVA (one-way), and Tukey's test (α=0.05). Results: The addition of 10% β-AgVO3 promoted antimicrobial activity against all strains. The antimicrobial effect was observed at a minimum concentration of 1% for P. aeruginosa, 2.5% for S. aureus, 5% for C. albicans, and 10% for S. mutans. Surface hardness and compressive strength increased significantly with the addition of 0.5% β-AgVO3 (p<0.05). Higher rates of the nanomaterial did not alter the mechanical properties of the resin in comparison with the control group (p>0.05). Conclusions: The incorporation of β-AgVO3 has the potential to promote antimicrobial activity in the acrylic resin. At reduced rates, it improves the mechanical properties, and, at higher rates, it does not promote changes in the control. .

Acrylic Resins/pharmacology , Anti-Infective Agents/pharmacology , Silver/pharmacology , Vanadates/pharmacology , Acrylic Resins/chemistry , Analysis of Variance , Anti-Infective Agents/chemistry , Candida albicans/drug effects , Candida albicans/growth & development , Compressive Strength , Dental Prosthesis/microbiology , Hardness Tests , Materials Testing , Microbial Sensitivity Tests , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/growth & development , Reproducibility of Results , Silver/chemistry , Staphylococcus aureus/drug effects , Staphylococcus aureus/growth & development , Statistics, Nonparametric , Streptococcus mutans/drug effects , Streptococcus mutans/growth & development , Surface Properties , Time Factors , Vanadates/chemistry
Braz. j. microbiol ; 45(3): 759-767, July-Sept. 2014. ilus, graf, tab
Article in English | LILACS | ID: lil-727000


Many Gram-negative pathogens have the ability to produce N-acylhomoserine lactones (AHLs) as signal molecules for quorum sensing (QS). This cell-cell communication system allows them to coordinate gene expression and regulate virulence. Strategies to inhibit QS are promising for the control of infectious diseases or antibiotic resistant bacterial pathogens. The aim of the present study was to evaluate the anti-quorum sensing (anti-QS) and antibacterial potential of five essential oils isolated from Lippia alba on the Tn-5 mutant of Chromobacterium violaceum CV026, and on the growth of the gram-positive bacteria S. aureus ATCC 25923. The anti-QS activity was detected through the inhibition of the QS-controlled violacein pigment production by the sensor bacteria. Results showed that two essential oils from L. alba, one containing the greatest geranial:neral and the other the highest limonene:carvone concentrations, were the most effective QS inhibitors. Both oils also had small effects on cell growth. Moreover, the geranial/neral chemotype oil also produced the maximum zone of growth inhibition against S. aureus ATCC 25923. These data suggest essential oils from L. alba have promising properties as QS modulators, and present antibacterial activity on S. aureus.

Anti-Infective Agents/pharmacology , Chromobacterium/drug effects , Lippia/chemistry , Oils, Volatile/pharmacology , Quorum Sensing/drug effects , Staphylococcus aureus/drug effects , Anti-Infective Agents/isolation & purification , Chromobacterium/metabolism , Chromobacterium/physiology , Microbial Sensitivity Tests , Oils, Volatile/isolation & purification , Pigments, Biological/analysis , Staphylococcus aureus/growth & development
Pesqui. vet. bras ; 34(2): 109-113, fev. 2014. ilus, tab
Article in English | LILACS | ID: lil-709851


Biofilms constitute a physical barrier, protecting the encased bacteria from detergents and sanitizers. The objective of this work was to analyze the effectiveness of sodium hypochlorite (NaOCl) against strains of Staphylococcus aureus isolated from raw milk of cows with subclinical mastitis and Staphylococcus aureus isolated from the milking environment (blowers and milk conducting tubes). The results revealed that, in the presence of NaOCl (150ppm), the number of adhered cells of the twelve S. aureus strains was significantly reduced. When the same strains were evaluated in biofilm condition, different results were obtained. It was found that, after a contact period of five minutes with NaOCl (150ppm), four strains (two strains from milk , one from the blowers and one from a conductive rubber) were still able to grow. Although with the increasing contact time between the bacteria and the NaOCl (150ppm), no growth was detected for any of the strains. Concerning the efficiency of NaOCl on total biofilm biomass formation by each S. aureus strain, a decrease was observed when these strains were in contact with 150 ppm NaOCl for a total period of 10 minutes. This study highlights the importance of a correct sanitation protocol of all the milk processing units which can indeed significantly reduce the presence of microorganisms, leading to a decrease of cow´s mastitis and milk contamination.

Biofilmes são constituídos de bactérias aderidas a uma superfície e aderidas entre si envolvidas por um polissacarídeo de constituição proteica, lipídica e glicídica que conferem uma barreira física às bactérias dentro deste microambiente. O objetivo deste trabalho foi analisar a eficácia do hipoclorito de sódio (NaOCl) contra estirpes de Staphylococcus aureus isoladas de leite cru de vacas com mastite subclínica e Staphylococcus aureus isolados do ambiente de ordenha (borrachas de ordenhadeiras e mangueiras condutoras de leite). Os resultados revelaram que, na presença de hipoclorito de sódio (150ppm), o número de células aderidas das 12 estirpes de S. aureus analisadas foi significativamente reduzido. Quando as mesmas estirpes foram avaliadas em condições de biofilme, diferentes resultados foram obtidos. Verificou-se que, após um período de contato de cinco minutos com NaOCl (150ppm), quatro estirpes (duas estirpes de leite, uma estirpe das borrachas das ordenhadeiras e uma estirpe de uma mangueira condutora de leite) ainda eram capazes de crescer. Com o aumento do tempo de contato do hipoclorito e as bactérias, cada vez maior, na concentração de 150ppm, não foi detectado o crescimento das estirpes. Em relação à eficácia do NaOCl na formação total da biomassa do biofilme por cada uma das estirpes de S. aureus, observou-se decréscimo da biomassa dos biofilmes quando estas estirpes estavam em contato com o NaOCl na concentração de 150ppm durante um tempo total de 10 minutos. O estudo demonstra a importância de um protocolo de saneamento correto de todas as unidades de processamento de leite, que pode, efetivamente, reduzir a presença de microrganismos de forma significativa, conduzindo a uma diminuição da mastite e da contaminação do leite.

Animals , Female , Biofilms/growth & development , Cattle , Sodium Hypochlorite/therapeutic use , Mastitis, Bovine/prevention & control , Staphylococcus aureus/growth & development , Milk/microbiology , Microscopy, Fluorescence/veterinary
Rev. chil. infectol ; 30(4): 361-367, ago. 2013. graf, tab
Article in Spanish | LILACS | ID: lil-690524


Background:Accumulation of bacteria in the pharynx is one of the risk factors of pneumonia due to ventilation. One of the methods of prevention from accumulation of bacteria in the pharynx is the use of oral solutions. Chlorhexidine is considered as the gold standard, but it has various side effects. Aim:Present study was aimed to determine and compare anti-bacterial effects of the chlorhexidine gluconate 0.2%, herbal mouthwash of Matrica® (chamomile extracts) 10%, PersicaTM 10% and normal saline in intensive care unit patients. Methods:In this double blind randomized clinical trial, 80 patients who were admitted in ICU divided into four groups of 20 patients each one. Researchers applied PersicaTM to group one, chlorhexidine gluconate mouth wash 0.2% to group two and third group received Matrica, finally in the control group, normal saline were used. In order to culturing of Staphylococcus aureusand S. pneumoniae,salivary samples were obtained without any stimulation after six minimums oral rinsing. The data were processed in SPSS17 software and analyzed by appropriate statistical tests. Results:Decreased rate of bacterial colonies after intervention in the whole four groups was significant (p < 0.001). The mouth wash of chlorhexidine (p < 0.001), PersicaTM (p: 0.008) and Matrica (p: 0.01) had a significant antibacterial effect on S. aureusand S. pneumoniae(p < 0.001). Conclusion:Herbal oral mouthwash of persica and matrica has the effect on S. pneumoniae and S. aureusof oropharynx area in mechanically ventilated patients. However, there is a need for further research to be considered as an alternative to chlorhexidine for prevention of VALP in ICU patients.

Introducción:La presencia y acumulación de bacterias en la cavidad oral es un factor de riesgo para el desarrollo de neumonía asociada a ventilación mecánica. Uno de los métodos para prevenir esta acumulación en la faringe es el uso de soluciones orales. Al respecto, clorhexidina es considerada el estándar de oro, pero tiene varios efectos colaterales. Objetivo:Determinar y comparar el efecto antibacteriano de gluconato de chorhexidina al 0,2%, aseo bucal con preparado en base a hierba matrica (extracto de chamomile) al 10%, Persica® al 10% y solución salina fisiológica (NaCl 9%0) en pacientes de la unidad de cuidados intensivos ingresados para ventilación mecánica. Métodos:Ensayo doble ciego, randomizado, sobre 80 pacientes ingresados en UCI, divididos en cuatro grupos de 20 miembros cada uno. El grupo I recibió Persica®, el grupo II aseo bucal con gluconato de clorhexidina al 0,2%, el grupo III recibió matrica y, finalmente, el grupo IV-control recibió solución salina fisiológica. Con la finalidad de cultivar Staphylococcus aureus yS. pneumoniae,se obtuvieron muestras de saliva sin efectuar estímulo alguno tras un mínimo de seis lavados bucales. Los datos fueron procesados en el software SPSS17 y analizados por tests estadísticos apropiados. Resultados:La disminución en el recuento de colonias bacterianas, después de la intervención, fue significativa en los cuatro grupos (p < 0,001). El aseo bucal con clorhexidina (p < 0,001), Persica® (p: 0,008) y matrica (p: 0,01) tuvo un significativo efecto antibacteriano sobre las especies S. aureusy S. pneumoniae(p < 0,001). Conclusión:El aseo bucal con solución en base a hierbas de Persica® y matrica tiene un efecto sobre S. pneumoniae y S. aureusde la cavidad oral en pacientes en régimen de ventilación mecánica. No obstante, se requiere de mayores estudios para considerarlo una alternativa a clorhexidina para la prevención de neumonías en pacientes de UCI.

Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Anti-Bacterial Agents/administration & dosage , Chlorhexidine/analogs & derivatives , Mouthwashes/administration & dosage , Plant Preparations/administration & dosage , Pneumonia, Ventilator-Associated/prevention & control , Prunus/chemistry , Anti-Bacterial Agents/pharmacology , Colony Count, Microbial , Chlorhexidine/administration & dosage , Chlorhexidine/pharmacology , Double-Blind Method , Mouthwashes/pharmacology , Plant Preparations/pharmacology , Pneumonia, Ventilator-Associated/microbiology , Staphylococcus aureus/drug effects , Staphylococcus aureus/growth & development , Staphylococcus aureus/isolation & purification , Streptococcus pneumoniae/drug effects , Streptococcus pneumoniae/growth & development , Streptococcus pneumoniae/isolation & purification
An. bras. dermatol ; 88(4): 518-521, ago. 2013.
Article in English | LILACS | ID: lil-686523


BACKGROUND: Atopic dermatitis leads to epidermal barrier dysfunction and bacteria colonization. The relationship of the last factor with the severity of the disease and the frequency of exacerbation is not fully known. OBJECTIVES: Verify the severity of the atopic dermatitis and the number of appointments generated by dermatosis, comparing patients colonized with patients not colonized by S. aureus. Verify the frequency of colonization by methicillin resistant Staphylococcus aureus acquired in the community. METHODS: Cohort study with a 12 months follow-up, in a sample of patients from Porto Alegre, RS public network. Cultures in active injuries and nasal cavities were carried out as well as methicillin sensitivity tests to S. aureus. The severity of atopic dermatitis was defined by Eczema Area and Severity Index (EASI). RESULTS: We included 93 patients, 43% female and 56% male, 26 colonized by S. aureus in the nasal orifices, 56 in the skin damage. The mean of initial Eczema Area and Severity Index was 5.5 and final 3.9. The initial Eczema Area and Severity Index of patients colonized by S. aureus in the skin and nasal cavity was larger than the number of patients without colonization(p< 0.05). During the period of one year, in average, there were six appointments/patient. There was linear correlation between the number of appointments during one year and the inicial Eczema Area and Severity Index (r = 0,78). There were no patients ...

FUNDAMENTOS: A Dermatite Atópica cursa com alteração da barreira cutânea e colonização bacteriana; a relação deste último fator com a gravidade da doença e a frequência das exacerbações não é completamente conhecida. OBJETIVOS: Verificar a gravidade da Dermatite Atópica e o número de consultas ocasionadas pela dermatose, comparando pacientes colonizados e não colonizados pelo Staphylococcus aureus (S. aureus). Verificar a frequência de colonização por Staphylococcus aureus meticilina resistentes da comunidade. MÉTODOS: Estudo de coorte, com 12 meses de acompanhamento, em amostra de pacientes da rede pública de Porto Alegre, RS. Realizaram-se culturais de lesões ativas e fossas nasais e testes de sensibilidade à meticilina para o S. aureus. A gravidade da Dermatite Atópica foi estabelecida pelo Eczema Area and Severity Index. RESULTADOS: Incluídos 93 pacientes, 43% femininos e 56% masculinos, 26 colonizados por S. aureus na região nasal, 56 em lesão cutânea. A média do Eczema Area and Severity inicial foi 5,5 e a do final 3,9. O Eczema Area and Severity Index inicial dos pacientes colonizados por S. aureus em lesão cutânea e nas fossas nasais foi maior que o dos pacientes não colonizados (p< 0,05). Em um ano, seis consultas por paciente ocorreram, em média. Houve correlação linear entre ...

Adolescent , Adult , Child , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Male , Young Adult , Appointments and Schedules , Dermatitis, Atopic/microbiology , Severity of Illness Index , Staphylococcus aureus/growth & development , Cohort Studies , Dermatitis, Atopic/pathology , Methicillin-Resistant Staphylococcus aureus , Microbial Sensitivity Tests , Skin/microbiology , Time Factors
J. pediatr. (Rio J.) ; 89(4): 394-399, ju.-ago. 2013. ilus
Article in Portuguese | LILACS | ID: lil-684139


OBJETIVO: Comparar o crescimento bacteriano em colostro puro e colostro com aditivo do leite materno contendo ferro. MÉTODOS: Foram comparadas 78 amostras de colostro puro ou colostro com adição de aditivo do leite materno contendo ferro para avaliar o crescimento de Escherichia coli, Staphylococcus aureus e Pseudomonas aeruginosa. Para a análise qualitativa, discos de papel-filtro foram imersos em amostras de cada grupo e incubados por 48 horas com 10¹ Unidades Formadoras de Colônias/mL de cada cepa. Para a avaliação quantitativa, 1 mL de cada cepa contendo 10(7) Unidades Formadoras de Colônias/mL foi homogeneizado com 1 mL, tanto de colostro puro quanto de colostro com aditivo do leite materno, espalhado em placa de Petri e incubado a 37ºC. O número de Unidades Formadoras de Colônias foi contado 24 horas depois. RESULTADOS: A análise qualitativa não mostrou nenhuma diferença no crescimento bacteriano. Na avaliação quantitativa, o crescimento de Escherichia coli (EC) no grupo C foi de 29,4±9,7 x 10(6) CFU/mL, enquanto no grupo FM85 foi de 31,2±10,8 x 10(6) CFU/mL. A diferença entre o crescimento médio foi de 1,9±4,9 x 10(6) CFU/mL (p = 0,001). Não houve diferenças no crescimento de Staphylococcus aureus e Pseudomonas aeruginosa. CONCLUSÃO: A adição de ferro a essa concentração reduz a ação bacteriostática do leite materno contra Escherichia coli.

OBJECTIVE: To compare bacterial growth in pure colostrum versus colostrum with human milk fortifier (HMF) containing iron. METHODS: The growth of Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa in 78 samples of pure colostrum or colostrum with added iron-containing HMF was compared. For qualitative analysis, filter paper discs were immersed in samples from each group and incubated for 48 hours with 10¹ colony forming units (CFUs)/mL of each strain. For quantitative assessment, 1 mL of each strain containing 10(7) CFUs/mL was homogenized with 1 mL of either colostrum or colostrum with human milk fortifier, seeded into a Petri dish, and incubated at 37ºC. Twenty-four hours later, the number of CFUs was counted. RESULTS: The qualitative analysis showed no difference in bacterial growth. In the quantitative evaluation, E. coli growth in the control group was 29.4±9.7 x 10(6) CFU/ mL, while in the HMF group it was 31.2±10.8 x 10(6) CFU/mL. The difference between the average growth was 1.9±4.9 x 10(6) CFU/mL (p = 0.001). There were no differences in S. aureus and P. aeruginosa growth. CONCLUSION: Addition of iron at this concentration reduces breast milk bacteriostatic action against E. coli.

Animals , Female , Humans , Pregnancy , Colostrum/microbiology , Food, Fortified , Gram-Negative Bacteria/growth & development , Gram-Positive Bacteria/growth & development , Gram-Positive Bacterial Infections/immunology , Iron , Milk, Human , Colostrum/immunology , Escherichia coli/growth & development , Gram-Negative Bacteria/immunology , Gram-Positive Bacteria/immunology , Gram-Positive Bacterial Infections/prevention & control , Iron/administration & dosage , Lactoferrin/physiology , Pseudomonas aeruginosa/growth & development , Staphylococcus aureus/growth & development
Article in English | WPRIM | ID: wpr-214993


BACKGROUND: Delayed entry of blood culture bottles is inevitable when microbiological laboratories do not operate for 24 hr. There are few studies reported for prestorage of these bottles. The growth dynamics of Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa were investigated with respect to various preincubation conditions. METHODS: Fifteen or 150 colony-forming units (CFU) of bacteria were inoculated into standard aerobic or anaerobic blood culture bottles. Bottles were preincubated at 25degrees C or 37degrees C for 0, 2, 4, 8, 12, 24, or 48 hr. The time to detection (TTD) then was monitored using the BacT/Alert 3D system (bioMerieux Inc., USA). RESULTS: Significant difference in TTD was observed following preincubation for 8 hr at 25degrees C vs. 4 hr at 37degrees C for S. aureus, 4 hr at 25degrees C vs. 4 hr at 37degrees C for E. coli, 12 hr at 25degrees C vs. 4 hr at 37degrees C for P. aeruginosa, compared to no preincubation (P<0.005). TTD values did not vary significantly with bacterial CFU or with aerobic or anaerobic bottle type. The BacT/Alert 3D system returned false negatives following preincubation of P. aeruginosa for 48 hr at 25degrees C or 24 hr at 37degrees C. CONCLUSIONS: TTD was mainly affected by preincubation temperature and duration rather than by input CFU quantity or bottle type for the 3 experimental bacteria.

Bacteriological Techniques/instrumentation , Culture Media , Escherichia coli/growth & development , Pseudomonas aeruginosa/growth & development , Staphylococcus aureus/growth & development , Temperature , Time Factors
J. appl. oral sci ; 20(6): 643-648, Nov.-Dec. 2012. ilus, tab
Article in English | LILACS | ID: lil-660635


OBJECTIVES: The purpose of this study was to evaluate the antimicrobial activity of an acrylic resin combined with an antimicrobial polymer poly (2-tert-butylaminoethyl) methacrylate (PTBAEMA) to inhibit Staphylococcus aureus, Streptococcus mutans and Candida albicans biofilm formation. MATERIAL AND METHODS: Discs of a heat-polymerized acrylic resin were produced and divided according to PTBAEMA concentration: 0 (control), 10 and 25%. The specimens were inoculated (10(7) CFU/mL) and incubated at 37ºC for 48 h. After incubation, the wells were washed and each specimen was sonicated for 20 min. Replicate aliquots of resultant suspensions were plated at dilutions at 37ºC for 48 h. The number of colony-forming units (CFU) was counted and expressed as log (CFU+1)/mL and analyzed statistically with α=.05. RESULTS: The results showed that 25% PTBAEMA completely inhibited S. aureus and S. mutans biofilm formation. A significant reduction of log (CFU+1)/mL in count of S. aureus (control: 7.9±0.8A; 10%: 3.8±3.3B) and S. mutans (control: 7.5±0.7A; 10%: 5.1±2.7B) was observed for the group containing 10% PTBAEMA (Mann-Whitney, p<0.05). For C. albicans, differences were not significant among the groups (control: 6.6±0.2A; 10%: 6.6±0.4A; 25%: 6.4±0.1A), (Kruskal-Wallis, p>0.05, P=0.079). CONCLUSIONS: Acrylic resin combined with 10 and 25% of PTBAEMA showed significant antimicrobial activity against S. aureus and S. mutans biofilm, but it was inactive against the C. albicans biofilm.

Acrylic Resins/pharmacology , Biofilms/drug effects , Candida albicans/growth & development , Methacrylates/pharmacology , Staphylococcus aureus/growth & development , Streptococcus mutans/growth & development , Acrylic Resins/chemistry , Anti-Infective Agents/chemistry , Anti-Infective Agents/pharmacology , Biofilms/growth & development , Colony Count, Microbial , Denture Bases/microbiology , Methacrylates/chemistry , Stem Cells
Braz. j. microbiol ; 43(2): 544-551, Apr.-June 2012. ilus, graf
Article in English | LILACS | ID: lil-644469


Ostrich raising around the world have some key factors and farming profit depend largely on information and ability of farmers to rear these animals. Non fertilized eggs from ostriches are discharged in the reproduction season. Staphylococcus aureus and Escherichia coli are microorganisms involved in animal and human diseases. In order to optimize the use of sub products of ostrich raising, non fertilized eggs of four selected birds were utilized for development of polyclonal IgY antibodies. The birds were immunized (200ug/animal) with purified recombinant staphylococcal enterotoxin C (recSEC) and synthetic recRAP, both derived from S. aureus, and recBFPA and recEspB involved in E. coli pathogenicity, diluted in FCA injected in the braquial muscle. Two subsequent immunization steps with 21 days intervals were repeated in 0,85% saline in FIA. Blood and eggs samples were collected before and after immunization steps. Egg yolk immunoglobulins were purified by precipitation with 19% sodium sulfate and 20% ammonium sulphate methodologies. Purified IgY 50µL aliquots were incubated in 850µL BHI broth containing 50µL inoculums of five strains of S. aureus and five strains of E.coli during four hours at 37ºC. Growth inhibition was evaluated followed by photometry reading (DO550nm). Egg yolk IgY preparation from hiperimmunized birds contained antibodies that inhibited significantly (p<0,05) growth of strains tested. Potential use of ostrich IgY polyclonal antibodies as a diagnostic and therapeutic tool is proposed for diseased animals.

Animals , Enterotoxins/isolation & purification , Escherichia coli/growth & development , Immunoglobulins/isolation & purification , Ovulation Inhibition , Recombinant Proteins/analysis , Recombinant Proteins/isolation & purification , Staphylococcus aureus/growth & development , Staphylococcus aureus/isolation & purification , Vaccination , Methods , Struthioniformes
Fisioter. pesqui ; 19(2): 153-157, abr.-jun. 2012. tab
Article in Portuguese | LILACS | ID: lil-644515


O objetivo deste estudo foi verificar o efeito bactericida do gerador de alta frequência sobre a cultura de Staphylococcus aureus. Para isso, 36 placas de Petri inoculadas com Staphylococcus aureus foram divididas em 6 grupos, sendo 4 tratados (G5-15, G5-10, G3-15 e G3-10) e 2 controles (GC3 e GC5). O G5-15 e o G5-10 foram tratados 5 vezes por semana durante 15 e 10 minutos respectivamente, enquanto o G3-15 e o G3-10 foram tratados 3 vezes por semana durante 15 e 10 minutos respectivamente. No tratamento, foi utilizado o gerador de alta frequência na intensidade 10, técnica de faiscamento com eletrodo standard. Após o 15º dia de tratamento, foram realizadas repicagens para verificar se houve crescimento de novas culturas, observando-se que apenas o G5-15 mostrou-se eficaz quando comparado ao GC5 (p=0,0039). Assim, o gerador de alta frequência apresentou efeito bactericida diante de cultura de Staphylococcus aureus in vitro em uma frequência de 5 vezes por semana aplicado por 15 minutos diários.

The purpose of this study was to check the bactericidal effect of the high frequency generator over the Staphylococcus aureus culture. A total of 36 Petri dishes inoculated with Staphylococcus aureus were divided into 6 groups, including 4 treated (G5-15, G5-10, G3-15 and G3-10) and 2 controls (GC3 e GC5). G5-15 and G5-10 were treated 5 times per week during 15 and 10 minutes, respectively, while G3-15 and G3-10 were treated 3 times per week during 15 and 10 minutes, respectively. In treatment, it was used the high frequency generator with intensity of 10, sparking technique with standard electrode. After the 15th day of treatment, there were performed transplanting, in order to check if there were growth of new cultures, and only G5-15 showed to be effective when compared to GC5 (p=0.0039). So, the high frequency generator had a bactericidal effect on Staphylococcus aureus in vitro culture at a frequency of 5 times per week and exposure time of 15 minutes daily.

Anti-Bacterial Agents , Bacterial Growth , Culture Media , Electromagnetic Radiation , Energy-Generating Resources , In Vitro Techniques , Ozone , Physical Therapy Modalities , Staphylococcus aureus/growth & development , Time Factors
Arch. latinoam. nutr ; 62(1): 68-72, mar. 2012. ilus
Article in English | LILACS | ID: lil-716439


The effect of the addition of lactoferrin on Staphylococcus aureus to Minas frescal cheese was evaluated. Three cheeses were made: control (S. aureus), Lf-2% (2% lactoferrin + S. aureus) and Lf-4% (4% lactoferrin + S. aureus). Cheeses were packaged and S. aureus populations were determined on days 1, 8, 15, 22 and 29 of storage at 6°C. The experiment was repeated three times. S. aureus population increased 1.3 logarithmic cycles in the control cheese during storage, while it decreased to numbers below the detection limit in cheeses containing lactoferrin, over the same period. Moreover, antimicrobial effect showed to be dose-dependent.

Ação antimicrobiana de lactoferrina sobre Staphylococcus aureus inoculado em queijo Minas frescal. O efeito da adição de lactoferrina sobre a viabilidade de Staphylococcus aureus inoculado em queijo Minas frescal foi avaliado. Três queijos foram produzidos: controle (S. aureus), Lf-2% (2% lactoferrina + S. aureus) e Lf-4% (4% lactoferrina + S. aureus). Os queijos foram armazenados e as populações de S. aureus foram determinadas durante o armazenamento refrigerado a 6°C nos dias 1, 8, 15, 22 e 29. Os experimentos foram realizados em triplicata. As populações de S. aureus aumentaram 1,3 ciclos logarítmicos nos queijos controle durante o armazenamento, enquanto que essas populações foram reduzidas abaixo do limite de detecção nos queijos contendo lactoferrina no mesmo período. Além disso, observou-se que o efeito antimicrobiano foi dose-dependente.

Anti-Infective Agents/pharmacology , Cheese/microbiology , Lactoferrin/pharmacology , Staphylococcus aureus/drug effects , Food Handling , Microbial Sensitivity Tests , Staphylococcus aureus/growth & development
Acta odontol. latinoam ; 25(3): 324-329, 2012. tab, graf
Article in English | LILACS | ID: lil-699396


El propósito de este trabajo fue analizar la prevalencia de Staphylococcus aureus y especies de Candida en muestras demucosa nasal de 100 individuos inmunocompetentes de ambos sexos con edades entre 18-70 años, durante el examen clínico estomatológico. Las muestras fueron obtenidas con hisoposestériles sobre la mucosa de ambas fosas nasales. Se realizó observación en fresco, tinción de Gram, Giemsa y cultivos en medios selectivos y diferenciales a 37ºC para el aislamiento e identificación de los microorganismos seleccionados, pruebas bioquímicas convencionales y equipos comerciales y estudios moleculares mediante la prueba de PCR. Con un termo higrómetro digital se midió la temperatura ambiente cuyo promedio en el momento de la toma en el consultoriofue de 25±2 oC y la humedad relativa ambiente fue del 66±11 por ciento.S aureus se aisló en el 38 por ciento de las muestras y dentro del mismo, 4 por ciento fueron meticilino resistentes (MRSA) siendo genéticamente 2 por ciento de la Comunidad (MRSA-CA) y 2 por ciento Hospitalarios (MRSA-HA).En el 23 por ciento de las muestras fue identificada Candida siendo la especie prevalente C. albicans: 19 por ciento y en menor proporción C. dubliniensis: 3 opr ciento , C. krusei: 1 por ciento. Se registró una asociación significativa entre Candida y S. aureus (Chi-cuadrado=27,75; gl=1; (p<0,001). La cavidad nasal constituye un reservorio yla identificación de género y especie contribuye a la adecuada vigilancia epidemiológica.

Humans , Male , Adolescent , Adult , Female , Middle Aged , Candida/growth & development , Nasal Cavity/microbiology , Immunocompromised Host , Staphylococcus aureus/growth & development , Colony Count, Microbial , Culture Media , Polymerase Chain Reaction/methods , Data Interpretation, Statistical
Indian J Pathol Microbiol ; 2011 Jul-Sept 54(3): 569-571
Article in English | IMSEAR | ID: sea-142045


Background: Microorganisms develop biofilm on various medical devices. The process is particularly relevant in public health since biofilm associated organisms are much more resistant to antibiotics and have a potential to cause infections in patients with indwelling medical devices. Materials and Methods: To determine the efficiency of an antibiotic against the biofilm it is inappropriate to use traditional technique of determining Minimum Inhibitory Concentration (MIC) on the free floating laboratory phenotype. Thus we have induced formation of biofilm in two strains (Pseudomonas aeruginosa and Staphylococcus aureus, which showed heavy growth of biofilm in screening by Tube method) in a flow cell system and determined their antibiotic susceptibility against ciprofloxacin by agar dilution method in the range (0.25 mg/ml to 8 mg/ml). The MIC value of ciprofloxacin for the biofilm produced organism was compared with its free form and a standard strain as control on the same plates. Observations: Both the biofilm produced strains showed a higher resistance (MIC > 8 mg/ml) than its free form, which were 2 μg/ml for Pseudomonas aeruginosa and 4 mg/ml for Staphylococcus aureus. Thus biofilm can pose a threat in the patient treatment.

Anti-Bacterial Agents/pharmacology , Biofilms/drug effects , Biofilms/growth & development , Ciprofloxacin/pharmacology , Humans , Microbial Sensitivity Tests , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/growth & development , Pseudomonas aeruginosa/physiology , Staphylococcus aureus/drug effects , Staphylococcus aureus/growth & development , Staphylococcus aureus/physiology
Iatreia ; 23(1): 5-9, mar. 2010.
Article in Spanish | LILACS | ID: lil-554056


En la última década han sido cada vez más frecuentes los informes de infecciones causadas porcepas de Staphylococcus aureus resistente a meticilina asociadas a la comunidad (CA-MRSA,por Community-associated methicillin-resistant S. aureus). La colonización juega un papelimportante en la epidemiología de tales infecciones. Sin embargo, los estudios de colonizaciónse han centrado principalmente en el ambiente hospitalario y se han hecho muy pocos en lacomunidad. En este trabajo se investigó la frecuencia de colonización por S. aureus en generaly por MRSA en las manos de individuos de la población general no relacionados con el área dela salud, empleando métodos fenotípicos y moleculares. Se obtuvieron mediante hisopado 800muestras de las manos de otros tantos individuos. Se halló colonización por Staphylococcusaureus en 65 muestras (8,1%) y por MRSA en 5 (0,63%). Las 5 cepas de MRSA presentaban elcasete cromosómico mec (SCCmec) de los tipos IV o V, típicamente relacionados con CA-MRSA.Nuestro trabajo evidenció la colonización de las manos por MRSA en individuos de la comunidad,lo cual constituye un importante factor de riesgo, no solo por su asociación con el desarrolloulterior de infecciones, sino también por el potencial de diseminar este microorganismo a lapoblación general.

Community-associated methicillin-resistant Staphylococcus aureus infections (CA-MRSA) havebeen reported with increasing frequency during the past decade. Colonization plays an importantrole in the epidemiology of such infections. However, colonization studies have focused mostlyon hospital settings and only a few have been carried out in communities. This was a study of thefrequency of hand colonization by S. aureus in generaland by CA-MRSA, by means of phenotypical andmolecular methods, in 800 adults from the communitywho had no relationship with the health area.Staphylococcus aureus colonization was found in 65individuals (8.1%) and MRSA was present in 5 (0.63%).The 5 MRSA strains were found to have mecchromosomic cassettes (SCCmec) of either type IV orV, typical of CA-MRSA. Our study provides evidence ofCA-MRSA colonization in the hands of individuals fromthe community. This constitutes an important riskfactor, not only by its association with subsequentinfections, but also for the risk of dissemination of thismicroorganism to the general population.

Humans , Staphylococcus aureus/growth & development , Staphylococcus aureus/pathogenicity
Arq. bras. oftalmol ; 72(5): 626-630, set.-out. 2009. ilus, tab
Article in English | LILACS | ID: lil-534180


OBJETIVO: Avaliar a influência da ação antimicrobiana das soluções multiuso para desinfecção de lentes de contato hidrofílicas. MÉTODOS: Duas soluções multiuso denominadas solução A (poliquaternário-1 a 0,001 por cento e miristamidopropil dimetilamina a 0,0005 por cento) e solução B (poliaminopropil biguanida a 0,0001 por cento) foram testadas em lentes de contato hidrofílicas contaminadas com Pseudomonas aeruginosa (ATCC27583), Staphylococcus epidermidis (ATCC1226), Klebsiella pneumoniae (ATCC13883), Staphylococcus aureus (ATCC25923) e Candida albicans (ATCC 10231) para verificar a quantidade de redução do crescimento dos microrganismos após o enxágue com as soluções. Foram seguidas as instruções preconizadas pelos fabricantes. RESULTADOS: Houve redução de 90 por cento do crescimento de Pseudomonas aeruginosa, Staphylococcus epidermidis, Staphylococcus aureus e Candida albicans. Não houve crescimento de Klebsiella pneumoniae. CONCLUSÃO: As soluções testadas neste trabalho mostraram redução do número de microrganismos testados.

PURPOSE: To evaluate the efficacy of disinfecting solutions in hydrophilic contact lenses (CL). METHODS: Two multi-use solutions denominated solution A (0.001 percent polyquaternium-1 and 0.0005 percent myristamidopropyl dimethylamine) and solution B (0.0001 percent polyaminopropyl biguanide) were used. The solutions were tested in hydrophilic contact lenses infected with Pseudomonas aeruginosa (ATCC27583), Staphylococcus epidermidis (ATCC1226), Klebsiella pneumoniae (ATCC13883), Staphylococcus aureus (ATCC25923) and Candida albicans (ATCC 10231) and the decrease in microorganisms growth after the hydrophilic contact lenses were cleaned with the respective solutions was verified. The manufacture's instructions were followed. RESULTS: A decrease of 90 percent of Pseudomonas aeruginosa, Staphylococcus epidermidis, Staphylococcus aureus, Candida albicans and a decrease 100 percent of Klebsiella pneumoniae was observed. CONCLUSION: The solutions decreased the amount of microorganisms tested.

Animals , Bacteria/drug effects , Candida albicans/drug effects , Contact Lens Solutions/pharmacology , Contact Lenses, Hydrophilic/microbiology , Disinfectants/pharmacology , Bacteria/growth & development , Biguanides/pharmacology , Colony Count, Microbial , Candida albicans/growth & development , Klebsiella/drug effects , Klebsiella/growth & development , Polymers/pharmacology , Propylamines/pharmacology , Propylamines/standards , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/growth & development , Staphylococcus aureus/drug effects , Staphylococcus aureus/growth & development , Staphylococcus epidermidis/drug effects , Staphylococcus epidermidis/growth & development
Electron. j. biotechnol ; 12(3): 10-11, July 2009. ilus, tab
Article in English | LILACS | ID: lil-551888


The formation of biofilms on indwelling/implanted medical devices is a common problem. One of the approaches used to prevent biofilm formation on medical devices is to inhibit bacterial attachment by modification of the synthetic polymers used to fabricate the device. In this work, we assessed how micro-scale features (patterns) imprinted onto the surface of silicone elastomer similar to that used for medical applications influenced biofilm formation by Staphylococcus aureus, Staphylococcus epidermidis, and Pseudomonas aeruginosa. Patterns were transferred from a multi-patterned oxidized silicon-wafer master-template to silicone elastomer. Features consisted of bars, squares, and circles each extending 0.51 µm above the surface. Feature sizes ranged between 1.78 and 22.25 µm. Distances separating features ranged between 0.26 and 17.35 µm. Bacterial biofilm formation on discs cut from imprinted silicone elastomer was assessed by direct microscopic observation and quantified as the surface area covered by biofilm. Unpatterned silicone elastomer served as a control. Several of the micro-scale patterns imprinted into the silicone elastomer significantly reduced biofilm formation by each bacterium and interrupted biofilm continuity. Although there were differences in detail among strains, bacteria tended to attach in the area between features more than to the surface of the feature itself.

Animals , Biofilms/growth & development , Biofilms , Pseudomonas aeruginosa/growth & development , Pseudomonas aeruginosa , Staphylococcus aureus/growth & development , Staphylococcus epidermidis/growth & development , Staphylococcus epidermidis , Silicone Elastomers/isolation & purification , Silicone Elastomers/analysis , Silicone Elastomers/adverse effects , Equipment and Supplies/microbiology