Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2014-11-26T12:17:54Z No. of bitstreams: 2 Dissertação - Marcel da Silva Garrote - 2013.pdf: 886747 bytes, checksum: 720948391469857f66e38d70ed31bae0 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2014-11-26T12:28:10Z (GMT) No. of bitstreams: 2 Dissertação - Marcel da Silva Garrote - 2013.pdf: 886747 bytes, checksum: 720948391469857f66e38d70ed31bae0 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-11-26T12:28:10Z (GMT). No. of bitstreams: 2 Dissertação - Marcel da Silva Garrote - 2013.pdf: 886747 bytes, checksum: 720948391469857f66e38d70ed31bae0 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2013-12-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Purpose:to evaluate the antibacterial effect of oral antiseptics (cetylpyridinium chloride, chlorhexidine gluconate and benzalkonium chloride) on S. mutans, E. faecalis andP. aeruginosa, determined by agar diffusion test and direct exposition test. Methods:The strains were inoculated in 7 mL BHI and incubated at 37°C for 24 hours. For agar diffusion test, 13 Petri plates with 20 mL BHIA were inoculated with 0.1 mL of microbial suspensions, aided by sterilized swabs, obtaining a confluent growth. Thirty six paper discs with 9 mm diameter were immersed in experimental solutions (cetylpyridinium chloride 0.07%, cetylpyridinium chloride 0.075%, chlorhexidine gluconate 0.12% and benzalkonium chloride 1.30 mg)for 1 minute. Following, at each plate, 3 paper discs containing irrigant solutions were put on BHIA surface. The plates were kept for 1 hour at environmental temperature and incubated at 37°C for 48 hours. Inhibition zones were measured over the paper discs containing the solutions, using two perpendicular measurements and obtaining the mean value. For direct exposition test, 516 sterilized paper points #50 were immersed on microorganisms suspension for 5 minutes, put in Petri plates and covered with 10 mL of irrigant solution. At 1, 5, 10 and 30 minutes intervals, 3 paper points were removed from substances contact, transported individually and immersed in 7 mL Letheen Broth, and incubated at 37°C for 48 hours. Bacterial growth was evaluated by medium turbidity. An inoculum of 0.1 mL Letheen Broth was transferred to 7 mL BHI, and incubated at the same conditions previously described. Bacterial growth was again evaluated by medium turbidity. Results: Inhibition zones were greater than 10 mm for all substances and in microorganisms tested. Benzalkonium chloride presented antibacterial effect against the biological markers after 12 5 minutes in direct exposition, while cetylpyridinium chloride and chlorhexidine gluconate presented antibacterial effect against all the microorganisms after 10 minutes. Conclusion:Theantiseptic solutions presented antibacterial effect against S. mutans, E. faecalis e P. aeruginosa. / Objetivo: avaliar o efeito antibacteriano de antissépticos bucais sobre S. mutans, E. faecalis e P. aeruginosa, por meio de testes de difusão em ágar e teste por exposição direta.Metodologia:Cepas de S. mutans (ATCC 25175), E. faecalis (ATCC 29212)e P. aeruginosa (ATCC 27853) foram inoculadas em 7 mL de BHI e incubadas a 37°C por 24 horas. Para o teste de difusão em ágar, 13 placas de Petri com 20 mL de BHIA foram inoculadas com 0,1 mL das suspensões microbianas, com auxílio de swab esterilizados, de modo a se obter um crescimento confluente. Trinta e seis discos de papel com 9 mm de diâmetro foram imersos nas soluções experimentais de cloreto de cetilpiridínio 0,07%, cloreto de cetilpiridínio 0,075%, gluconato de clorexidina 0,12% e cloreto de benzalcônio 0,13% mg durante um minuto. A seguir, três discos de papel contendo uma das soluções antissépticas foram colocados sobre a superfície do BHIA. As placas foram mantidas por uma hora em temperatura ambiente e incubadas a 37°C por 48 horas. Os diâmetros dos halos de inibição microbiana foram medidos valendo-se de duas medidas de forma perpendicular entre si, sendo obtida a média de seus comprimentos. Para o teste de exposição direta, 576 cones de papel absorventes esterilizados n°50 foram imersos na suspensão de micro-organismos por 5 minutos, e a seguir foram colocados em placas de Petri e cobertos com 10 mL de uma das soluções testes. Em intervalos de 1,5, 10 e 30 minutos, 3 cones de papel absorventes foram retirados do contato com as substâncias, transportados individualmente e imersos em 7 mL de Letheen Broth, e incubados a 37°C por 48 horas. O crescimento microbiano foi avaliado pela turbidade do meio de cultura. Um inóculo de 0,1 mL obtido do Letheen Broth foi transferido para 7 mL de BHI, e incubado nas mesmas condições descritas. O 10 crescimento microbiano foi novamente avaliado pela turbidade do meio de cultura. Resultados: Os halos de inibição foram maiores que 10 mm para todas as substâncias e em todos os micro-organismos. A solução de cloreto de benzalcônio apresentou efeito antibacteriano contra os indicadores biológicos após 5 minutos em teste por exposição direta, enquanto que o cloreto de cetilpiridínio e o gluconato de clorexidina apresentaram efeito antibacteriano somente após 10 minutos. Conclusão: As soluções antissépticas estudadas apresentaram efeito antibacteriano por contato direto frente S. mutans, E. faecalis e P. aeruginosa.

Submitted by Aline Batista (alinehb.ufpel@gmail.com) on 2018-05-17T13:10:35Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Greici_Bergamo.pdf: 1545748 bytes, checksum: 9414284e23fa423a21e4c707896b4be1 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-05-17T14:50:34Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Greici_Bergamo.pdf: 1545748 bytes, checksum: 9414284e23fa423a21e4c707896b4be1 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-05-17T14:50:40Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Greici_Bergamo.pdf: 1545748 bytes, checksum: 9414284e23fa423a21e4c707896b4be1 (MD5) / Made available in DSpace on 2018-05-17T14:50:40Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_Greici_Bergamo.pdf: 1545748 bytes, checksum: 9414284e23fa423a21e4c707896b4be1 (MD5) Previous issue date: 2015-03-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Foram avaliados e comparados um método molecular (Molecular Detection System - 3M MDS®) e dois métodos fenotípicos (MAPA e MSRV) na detecção de Salmonella spp. Dois métodos utilizam como base meios de cultura, sendo que o Método MAPA é considerado padrão no Brasil, é recomendado pelo Ministério da Agricultura, Pecuária e Abastecimento e está descrito na Instrução Normativa N.62 e o Método MSRV que é descrito pela International Organization for Standardization. O terceiro método, 3M MDS®, é validado pela Association of Official Analytical Chemistry e baseia-se em princípios de biologia molecular detectando o micro-organismo alvo através de bioluminescência. Os três métodos foram avaliados quando a sua capacidade de detectar Salmonella spp. em amostras de leite UHT artificialmente contaminado e em amostras de linguiças mista frescal (elaborada com carne suína e bovina) e suína frescal adquiridas em estabelecimentos comerciais da Região Sul do Brasil. A partir dos isolados encontrados nas amostras de produtos cárneos, foi avaliada a capacidade de resistência a agentes antimicrobianos e de formação de biofilme em superfícies de poliestireno. Todos os métodos foram capazes de detectar um número equivalente de isolados de Salmonella spp. tanto nas amostras de leite UHT contaminadas artificialmente como em amostras de produtos cárneos. A sensibilidade e especificidade dos métodos foram equivalentes. A presença de Salmonella spp. foi observada em 19,1% (n=89) das amostras de produtos cárneos, estando essas impróprias para o consumo. Dos isolados obtidos, 40%(n=15) mostraram-se resistentes a pelo menos um dos agentes antimicrobianos testados e os que apresentaram menor eficiência foram a ampicilina, gentamicina e amoxicilina mais clavulanato. Apenas um antimicrobiano amicacina (30μg) foi eficaz na inibição de todos os isolados testados. Nenhum dos isolados mostrou-se capaz de formar biofilmes em superfícies de poliestireno. A partir dos dados obtidos pode-se inferir que tanto o Método 3M MDS®, quanto o Método MSRV podem ser utilizados como alternativas ao Método MAPA, considerado padrão no Brasil. A presença de Salmonella spp. observada nas amostras analisadas denotam falhas e falta de cuidados higiênicos na cadeia de carnes e a resistência bacteriana verificada nos isolados de Salmonella spp. a agentes antimicrobianos é preocupante pois bactérias resistentes podem gerar infecções de difícil tratamento. / One molecular method (Molecular Detection System - 3M MDS®) and two phenotypic methods (MAPA and MSRV) were evaluated and compared for the identification of Salmonella spp. in UHT milk artificially contaminated samples and mixed sausage frescal samples (manufactured using meat swine and meat beef) and swine sausage frescal samples bought in commercial markets in Southern Brazil. Two methods use the culture media: the MAPA method is considered standard in Brazil and is recommended by Ministry of Agriculture, Livestock and Supply and is described in Normative Instruction n.62 and MSRV method is recommended by International Organization for Standardization. The 3M MDS® method is recommended by Association of Official Analytical Chemistry, based on principles of molecular biology detecting the microorganism by bioluminescence. Salmonella spp. isolates found in the samples of meat products was evaluated the antimicrobial resistance and biofilm formation on polystyrene surfaces. All methods detect an equivalent number of Salmonella spp. isolates in UHT milk artificially contaminated samples and meat products. The sensitivity and specificity of both methods are equivalent. The presence of Salmonella spp. was observed in 19,1% (n=89) of the meat products samples and the antimicrobial resistance in Salmonella spp. isolates was 40% (n=15). Less efficient antibiotics: ampicillin, gentamicin and amoxicillin+clavulanate. Only one antibiotic - amikacin (30μg) - was effective in inhibiting all isolates tested. No Salmonella spp. isolate biofilms formed on polystyrene surfaces. The MSRV and 3M MDS® methods can be used as alternatives to the standard method MAPA. The presence of Salmonella spp. in meat products demonstrates flaws and lack of hygienic care in the meat chain and the resistance to antibiotics found in isolates of Salmonella spp. is worrying because the bacterial resistance can cause infections difficult to treat.

Quaternary ammonium salts are surface active bactericides. A mechanism of their biological activity has been well studied experimentally, and it encompasses two stages. The first stage involves electrostatic interactions of polar functional groups of the salts with oppositely charged functional groups on a bacterial cell surface, and the second stage includes incorporation of their lipophilic groups into a bacterial cell membrane. However, despite numerous experimental studies, computational modelling of this mechanism with the aim to support experimental observations with theoretical conclusions, to the author's knowledge, has not yet been reported. In the current study, linear regression models correlating theoretical descriptors of lipophilicity and electronic properties of mono- and disubstituted imidazolium carboxylates with their biological activity towards Escherichia coli have been developed. These models established that biological activity of these salts is governed by the chemical structures of imidazolium cations, and that the centre of this biological activity is located in the long alkyl side chains of the cations. It was also found that these side chains have an intrinsic electronic potential to form internal C-H- -H-C electrostatic interactions when their lengths reach seven carbon atoms. Additionally, the nature of the C-H- -O-C inter-ionic electrostatic interactions in imidazolium carboxylates has been explored via a topological analysis of these interactions in 1-ethyl-3-methylimidazolium acetate. Thus, it was established that these electrostatic interactions are hydrogen bonds.

Inicialmente, os cultivos foram desenvolvidos empiricamente e voltados para a produção de alimento humano. Mais tarde, com a descoberta da utilidade dos ficocolóides, os cultivos passaram a ser realizados também para a produção de biomassa para sua extração. Entretanto, sustentabilidade da indústria de macroalgas reside em grande parte nos cultivos, uma vez que os bancos naturais não são suficientes para atender a demanda crescente. Apesar do ágar estar presente nas paredes celulares de espécies de Gracilaria, seu ágar não era explorado comercialmente por apresentar características consideradas inadequadas pela indústria. A descoberta de que a hidrólise alcalina dos grupos sulfato do ágar aumentaria sua força de gel impulsionou a exploração comercial deste gênero. Assim, espécies pertencentes ao gênero Gracilaria são cada vez mais empregadas para a produção de ágar alimentício e a sua tem sido consideravelmente aumentada por meio do desenvolvimento de técnicas de cultivo. Embora a explotação de macroalgas no Brasil tenha se iniciado por volta de 1940, seu impacto social e econômico é reduzido. Estudos sobre a viabilidade de cultivo de macroalgas foram realizados ao longo da costa brasileira, com resultados positivos sobre o potencial de algumas espécies. Apesar disso, o país ainda não possui cultivos de macroalgas em escala comercial. Com base nestes antecedentes, o presente trabalho avaliou o desempenho do cultivo no mar de Gracilaria domingensis e de G. caudata e caracterizou as propriedades do seu ágar (rendimento e qualidade), na Enseada de Armação do Itapocoroy (Penha, Santa Catarina). Os resultados mostraram que o sistema de cultivo testado para ambas espécies é viável na Enseada. O ágar de G. domingensis extraído com CaCl2 apresentou melhores rendimentos e teores de 3,6-anidrogalactose, enquanto a extração com NaOH mostrou ser a mais adequada para G. caudata e ambas espécies mostraram potencial como matéria-prima para extração de ágar alimentício. / Seaweed cultivation in the world began with empirical methodologies to propagate some species utilized as food. Later on, with the discovery of a process to extract and purify agar, it was soon realized that, because of the large volumes needed by a growing industry this activity would only be sustainable if based on mariculture once the natural beds were being depleted. Despite it was known that agar could also be extracted from Gracilaria species, besides the traditional species of Gelidium, that genus yielded a product with lower value. It was only after the discovery that an alkaline treatment could remove part of the sulphate that reduced the gel strength, and therefore improved the agar quality, that the commercial cultivation of Gracilaria species really got momentum and developed continuously. Nowadays, most of the agar produced in the world is based on Gracilaria spp. Although the exploitation of seaweeds for agar production in Brazil started as early as 1940, up to now our production is still very modest due to the limited biomass in the natural beds. Several attempts to cultivate local Gracilaria spp. have been made, some of which with promising results, but a real commercial mariculture never developed in Brazil so far. Based on that we developed this project aiming at the development of viable techniques to cultivate two species of Gracilaria common at the Enseada de Armação do Itapocoroy (Penha, Santa Catarina): Gracilaria domingensis and G. caudata. We also tested different protocols to better extract the agar from the selected species, comparing their yields and quality. Our results show that with some adaptations of the methodologies for cultivation and agar extraction utilized elsewhere it may be possible to make this a viable alternative.

As proteínas inibidoras de poligalacturonases (PGIPs) presentes na parede celular são capazes de limitar o potencial destrutivo da poligalacturonase (PG) fúngica e, assim, constituem um tipo importante dentre os diversos sistemas de defesa do tecido vegetal frente à infecção fúngica. No mamão, o ataque fitopatogênico é o principal causador de danos pós-colheita, e sua alta susceptibilidade pode estar relacionada com a baixa eficácia ou pouca abundância dos meios de defesa anti-fitopatogênica. Uma vez que isso pode estar relacionado com as PGIPs e nada se conhece sobre o papel dessas proteínas nesse fruto, o objetivo do trabalho foi clonar os genes das PGIPs de mamoeiro e definir seu padrão de expressão em diferentes órgãos e tecidos e ao longo do amadurecimento. Para tanto, foram identificadas no genoma do mamoeiro, a partir de critérios que definem a identidade de uma PGIP, duas prováveis sequências dentre 13 candidatas iniciais. Ambas foram clonadas a partir das sequências genômicas e de cDNA, sequenciadas e sua identidade confirmada, sendo denominadas Cppgip4 e Cppgip6. As análises de expressão relativa em diversos tecidos e idades fisiológicas do mamoeiro demonstraram que os dois genes apresentaram diminuição da expressão com o desenvolvimento dos frutos, sendo que com a polpa apresentou redução dos níveis de expressão relativa de Cppgip4 em até 18 vezes dos 30 dias pós-antese (DPA) ao 9 dias pós-colheita (DPC). Na casca também houve redução significativa da expressão com o desenvolvimento. Para a expressão absoluta, nos frutos, sementes, caules, raízes e folhas, o número de cópias de ambos os transcritos decresceu com o desenvolvimento, sendo cerca de cem mil vezes mais abundante para Cppgip6 que para Cppgip4. As tentativas de expressão de proteínas recombinantes em Pichia pastoris não geraram resultado positivo, provavelmente em virtude das condições ideais de indução ainda não terem sido estabelecidas corretamente para o ensaio. A atividade de PGIPs extraídas diretamente do tecido foi medida por análise de difusão em ágar empregando pectinase de Aspergillus niger e revelou uma tendência à diminuição da porcentagem de inibição à medida que os frutos se desenvolveram, em concordância com os resultados da análise por qPCR. O conjunto de resultados sugere que a expressão varia com o estádio de desenvolvimento do fruto e é tecido-específica, possivelmente em resposta à diferente susceptibilidade dos tecidos ao ataque fitopatogênico, indicando que menores níveis de transcritos e atividade no amadurecimento, período de maior susceptibilidade, poderiam sinalizar para a regulação do processo degradativo marcando o início da senescência. / Polygalacturonase inhibiting proteins (PGIPs) present in plant cell walls are able to inhibit the destructive action of fungal polygalacturonase (PG). In this way, they constitute an important type of plant defense system against fungal infections. In papaya fruit, the pathogenic attack is the main cause of post harvesting loss, and its high susceptibility may be related to the low efficiency or low abundance of anti-phytopathogenic defense. Since this fact could be related to PGIPs expression and little is known about the response of these proteins in the fruit, the aim of the present work was to clone the genes of PGIPs papaya fruit and set their expression pattern in different organs and tissues throughout fruit ripening. Thus, two probable PGIP sequences among 13 initial candidates were identified in the papaya genome by using specific criteria. Both sequences were cloned from cDNA and genomic samples, sequenced and confirmed its identity, and then being named Cppgip4 and Cppgip6. Analysis of relative expression in various tissues at different physiological stages demonstrated that both genes were down regulated during fruit development. The relative expression levels of Cppgip4 in papaya pulp was reduced by 18 times from the 30 days post-anthesis (DPA) to the 9 days post-harvest (DPH). Similarly, gene expression in papaya peel was significant down regulated during fruit development. Absolute expression analysis revealed gene expressions in the fruit pulp, seed, stem, root and leaf were also down regulated within development. Moreover, Cppgip6 gene expression was a hundred thousand times more abundant than Cppgip4. The recombinant protein expression in Pichia pastoris did not result positive, probably because of the ideal conditions of induction have not been properly established the yet. The activity of PGIPs extracted directly from the tissue was measured by the agar diffusion assay using pectinase from Aspergillus niger and showed decrease of inhibition during fruit developed in accordance with the results of the qPCR analysis. Based on the results it is possible to suggest the expression of these genes varies temporally with the developmental stage of the fruit and is tissue-specific, possibly in response to the different susceptibility of tissues to pathogenic attack. In addition, the lowest levels of PGIP expression were achieved at the fruit ripening, when the susceptibility to fungal infection is high and could signal for regulating the degradation process characterized by the onset of senescence.

Made available in DSpace on 2016-07-18T17:51:14Z (GMT). No. of bitstreams: 1 Joice Yuri Minamiguchi.pdf: 940892 bytes, checksum: 640b533bbf1ddeb7da432aa4e6083c07 (MD5) Previous issue date: 2013-03-12 / Sweet potato culture has a high potential for human and animal feeding; and for this last purpose the branches can be used as hay. Is a high yield root, rich in nutrients which occupy marginal crop lands. The propagation is highly vegetative using branches or shoots from roots, what can affect it by disseminating pathogens. The main objective of this work was to evaluate the effect of gelling agents and a systemic disinfectant in sweet potato tissue culture. Two experiments were done; one with different doses of gelling agents (Agar and Phytagel®) and another with a response curve of isothiazolinones (Kathon®CG). Shoots and roots Length and dry weight, their development rates; biochemical parameters as proline accumulation and Superoxide Dismutase were evaluated. Sweet potato did not respond to different gelling agents, and the recommendation is to use the low cost effective. Kathon®CG reduced the growth in the different concentrations. The return to the medium without Kathon®CG improved the plantlet growth. / A cultura da Ipomoea batatas (L.) é de imenso potencial alimentar, tanto para seres humanos quanto para animais. É uma raiz de alto rendimento e rico em nutrientes, que ainda ocupa áreas marginais da agricultura. A propagação é vegetativa utilizando-se ramas ou brotações de raízes para plantio. Porém, estes métodos podem afetar a propagação desta espécie, uma vez que pode disseminar doenças. O objetivo deste trabalho foi avaliar gelificantes e um desinfetante sistêmico na cultura de tecido de batata-doce. Para isso dois experimentos foram montados, um comparando três doses de cada um dos gelificantes (agar e Phytagel®) e outro uma curva de doses de isotiazolinonas (Kathon®CG). Foram avaliados parâmetros de desenvolvimento como altura e massa seca dos explantes, e as taxas de desenvolvimento de cada um, além parâmetros bioquímicos, como acúmulo de prolina e atividade da superóxido dismutase. A batata-doce não respondeu positivamente aos diferentes gelificantes, recomendando-se então o de menor custo. O Kathon®CG provocou redução no crescimento dos explantes em qualquer dose. O retorno ao meio sem o Kathon®CG promoveu incremento no crescimento das plantas sob condições experimentais oferecidas. Batata-doce não se comporta como espécie acumuladora de prolina.

No description available.

Background: Vancomycin-resistant enterococci (VRE) is a common nosocomial infection. It classifies as Enterococcus faecalis or faecium carrying vanA or vanB gene that alters the bacterial cell wall hence lowering affinity for Vancomycin. Screening for VRE in Swedish hospitals are performed with stool sample pre-grown in selective broth followed by PCR and culture on selective media. Viasures Vancomycin resistance, Real Time PCR Detection Kit indicates that pre-growth in broth is not needed for the analyze. Aim: Comparison between the PCR kit and the subsequent culture on chromogenic agar with or without pre-growth in selective broth. Method: E. faecium with vanA gen (CCUG 36804) and E. faecalis with vanB gen (ATCC 51299) were suspended in different concentrations and added to ESwab transport medium. Thereafter small samples from the ESwab tube were enriched in selective broth. Samples from both selective broth and ESwab medium were analyzed with Viasures PCR kit on BD-MAX system and cultivated on chromogenic agar. Results: With pre-growth in selective broth the genes were found in every sample regardless of pre-concentration in the ESwab medium. Without enrichment the PCR kit always amplified the genes when the concentration was 40 000 cfu/ml for E. faecium (vanA) and ≥ 10 000 cfu/ml for E. faecalis (vanB). Colonies grew on chromogenic agar in every concentration from both ESwab and selective broth. Conclusion: Culture on chromogenic agar is comparable with or without pre-growth in selective broth but Viasure’s PCR kit is not equal for both methods in lower concentrations of the bacteria.

Indiana University-Purdue University Indianapolis (IUPUI) / Resilon is a resin-based obturation material that claims to create a monoblock through bonding of RealSeal sealer to the dentin walls and to the core material. Resilon is comprised of a biodegradable polymer, polycaprolactone, and inorganic fillers. Resilon has been shown to undergo enzymatic hydrolysis by bacterial enzymes such as lipase. This study aims to demonstrate if bacteria found within the infected root canal system are capable of degrading Resilon utilizing an agar disc hydrolysis method. A 0.1-percent Resilon emulsion and a gutta-percha emulsion were prepared with Tryptic Soy Agar in plates. Several bacterial species were inoculated in eight spots each on the Resilon and gutta-percha agar plates and the plates were observed for the formation of hydrolytic halos surrounding bacteria signifying their ability to degrade the material. The bacterial enzyme Lipase PS served as a positive control. P. intermedia, P. aeruginosa, P. assacharoylitica, S. epidermidis and S. aureus all demonstrated hydrolytic halos, clear zones, at each of the eight inoculation locations (100%, 95%CI 63%-100%) on the Resilon plates. The halos were similar to those seen in the positive lipase control. No halos were seen with E. faecalis, F. nucleatum, S. mutans, S. sanguis, or P. gingivalis at any of the eight inoculation spots (0%, 95%CI 0%-37%) on the Resilon plates. No hydrolytic halos were seen around any bacterial colonies or the Lipase PS on the gutta-percha plates. The results of this study indicate that bacteria found in endodontic infections can hydrolize Resilon dispersed into an emulsion. The potential exists for Resilon degradation after its use as an obturation material in infected root canal systems. Given that root canal therapy does not render a canal void of microorganisms, it is prudent to obturate the root canal system with a material that cannot be degraded by bacteria and their enzymes.

Actinomyces species play an important role in the pathogenesis of oral diseases and infections. Susceptibility testing is not always routinely performed, and one may oversee a shift in resistance patterns. The aim of the study was to analyze the antimicrobial susceptibility of 100 well-identified clinical oral isolates of Actinomyces spp. against eight selected antimicrobial agents using the agar dilution (AD) and E-Test (ET) methods. We observed no to low resistance against penicillin, ampicillin-sulbactam, meropenem, clindamycin, linezolid and tigecycline (0–2% ET, 0% AD) but high levels of resistance to moxifloxacin (93% ET, 87% AD) and daptomycin (83% ET, 95% AD). The essential agreement of the two methods was very good for benzylpenicillin (EA 95%) and meropenem (EA 92%). The ET method was reliable for correctly categorizing susceptibility, in comparison with the reference method agar dilution, except for daptomycin (categorical agreement 87%). Penicillin is still the first-choice antibiotic for therapy of diseases caused by Actinomyces spp.