A sepse é uma doença de alta mortalidade e o uso adequado de antimicrobianos no seu manuseio é essencial na obtenção de melhores resultados. O objetivo deste estudo foi avaliar o consumo de antimicrobianos em pacientes com sepse hospitalar com agente etiológico identificado no sangue, comparando a reação em cadeia da polimerase (PCR) - LightCycler® SeptiFast (SF) para a detecção rápida de microorganismos à hemocultura convencional nos primeiros 14 dias de tratamento. Os objetivos secundários incluíram descrever o percentual de positividade e a concordância entre o teste molecular e a hemocultura, o tempo de internação hospitalar, os custos diretos dos antimicrobianos utilizados e a letalidade em 10 e 28 dias. Entre outubro de 2012 e maio de 2016, foram incluídos 200 pacientes adultos com sepse hospitalar: 100 alocados no grupo intervenção onde a terapia antimicrobiana foi ajustada após a identificação do micro-organismo pelo SF (dentro de 6 a 12 horas) e 100 pacientes no grupo controle onde a terapia antimicrobiana foi ajustada após a identificação do microrganismo pela hemocultura (dentro de 48 a 72 horas). O consumo de antimicrobianos foi de 1429 (1071-2000) DOT por 1000 pacientes-dia no grupo intervenção versus 1889 (1357-2563) DOT por 1000 pacientes-dia no grupo controle (p = 0.017). O SF apresentou positividade de 25,9% enquanto a positividade da hemocultura foi de 22,9% (p = 0,452). O tempo de descalonamento antimicrobiano foi de 8 horas (7-14) versus 54 horas (38-75) (p < 0,001), enquanto a mortalidade em 10 e 28 dias foi de 21% e 36,8% no grupo de intervenção versus 37% e 44% no grupo controle, (p = 0,710 e p = 0,632), respectivamente. Não houve diferença no tempo de internação hospitalar e no custo direto dos antimicrobianos utilizados nos dois grupos. A duração média da terapia antimicrobiana em dias foi menor no grupo intervenção (12 ± 5 versus 15 ± 4, p = 0,039) em comparação com o grupo controle / Sepsis is a high mortality disease. Appropriate use of antimicrobials is essential to improve outcomes. The aim of the present study was to determine whether the use of the multiplex polymerase chain reaction LightCycler® SeptiFast (SF) assay reduces the antibiotic consumption through early de-escalation in patients with nosocomial sepsis compared with conventional blood cultures (BC) in the first 14 days of treatment. Secondary outcomes included the percentage of microorganisms identified through SF and BC (in both groups), timing of antimicrobial de-escalation, length of stay, direct costs of the antimicrobial drugs and mortality at 10 and 28 days. Between October 2012 and May 2016 adult patients with nosocomial sepsis were randomized in intervention group and control group: antimicrobial therapy was adjusted following the identification of microorganisms by SF (within 6 to 12 hours) or BCs (within 48 to 72 hours), respectively. A total of 200 patients were included (100 in each group). The median antimicrobial consumption was 1429 (1071-2000) DOT/1000 patients-day in the intervention group versus 1889 (1357-2563) DOT/1000 patients-day in the control (p = 0.017). Microorganism identification was 25.9% versus 22.9% (p = 0.452), timing of antimicrobial de-escalation was 8 hours (7-14) versus 54 hours (38-75) (p < 0.001) while the mortality rate at 10 and 28 days was 21% and 36.8% in the intervention group versus 37% and 44% in the control group, (p = 0.710 and p = 0.632), respectively. There was no difference in length of stay and antimicrobial costs between groups. The mean duration of antimicrobial therapy was lower in the SF group (12 ± 5 vs. 15 ± 4, p = 0.039) comparing to BC group. The use of a rapid molecular blood test resulted in a reduction in the antimicrobial consumption and a more rapid de-escalation in patients with nosocomial sepsis when compared to the standard management of blood culture

A candidose bucal acomete grande número de pessoas mundialmente, sendo associada a condições como imunossupressão, radioterapia, tabagismo, higiene bucal, idade, xerostomia e uso de próteses removíveis. Uma importante abordagem terapêutica para essas infecções consiste nos medicamentos antifúngicos, que podem apresentar efeitos colaterais e resultar na resistência dos patógenos. Nesse contexto, a terapia fotodinâmica (PDT) faz-se interessante como alternativa capaz de minimizar essas limitações. Protocolos de PDT poderão ser mais facilmente assimilados à prática clínica se empregarem materiais já aprovados para uso odontológico. Sendo assim, este estudo propõe avaliar o uso de PDT com eritrosina como fotossensibilizador, irradiada por um LED azul, usando-se um modelo animal. Quarenta camundongos tiveram candidose induzida sobre o dorso da língua por meio de imunossupressão e inoculação com Candida albicans. Após estabelecimento da lesão durante cinco dias, os animais receberam um dentre quatro tratamentos possíveis: aplicação da eritrosina 5% seguida de irradiação pelo LED (E+L+); aplicação de eritrosina, somente (E+L-); salina seguida pela irradiação (EL+); e somente salina (E-L-). A fim de distinguir possíveis efeitos colaterais, os mesmos tratamentos foram aplicados em 12 camundongos sem a indução de candidose. O número de unidades formadoras de colônia de C. albicans foi contado após o tratamento, e a mucosa foi submetida à análise histológica para determinar o grau de inflamação. Os dados dos grupos foram comparados por meio de ANOVA e teste de Kruskal-Wallis, (&alpha;=0,05). Não foram detectadas diferenças significativas entre os grupos testados quanto à contagem de colônias de C. albicans e o grau de inflamação. O infiltrado inflamatório foi classificado como discreto na maioria dos casos. Os animais com candidose bucal induzida e os saudáveis que foram submetidos aplicação de eritrosina 5% e irradiação pelo LED apresentaram infiltrado inflamatório mais acentuado e lesões mais evidentes na camada epitelial, sugerindo que este protocolo ocasionou danos aos tecidos orais. / Oral candidosis affects many people worldwide and is associated with conditions such as immunosuppression, radiation, smoking, oral hygiene, age, xerostomia and use of removable prostheses. An important therapeutic approach for these infections consists of antifungal drugs, which have side effects and can result in the resistance of pathogens. In this context, photodynamic therapy (PDT) is an interesting alternative able to overcome those limitations. PDT protocols can be more easily assimilated in clinical practice if they employ materials already approved for use in dentistry. Thus, this study evaluate the PDT with the use of erythrosine as a photosensitizer, irradiated by a blue LED light, using an animal model. Forty mice had candidosis induced on the tongue by the immunosuppression and inoculation with Candida albicans. After five days that the lesion is established, the animals received one of four possible treatments: application of 5% erythrosine and irradiation by the LED (E+L+); erythrosine application, only (E+L- ); saline followed by irradiation (E-L+); and only saline (E-L-). In order to distinguish potential side effects, the same treatments were applied in 12 mice without induced candidosis. Colony-forming units (CFU) of C. albicans were counted after treatment, and the mucosa was subjected to histological analysis to determine the degree of inflammation. The data of the groups were compared using ANOVA and Kruskal-Wallis test (&alpha;=0.05). No significant difference was detected among the groups tested for the number of CFU of C. albicans and the degree of inflammation. The inflammatory infiltrate was classified as mild in most cases. Animals with induced oral candidosis and the healthy ones exhibited more pronounced inflammatory infiltrate and lesions in the epithelial layer following PDT by 5% erythrosine and irradiation by the LED light. Such findings suggest that this protocol resulted in damage to oral tissues.

Foram avaliados dentifrícios experimentais à base de Ricinus communis (DR), Triclosan (DT) e Cloramina-T (DC) para higiene de próteses totais, tendo como controle dentifrício sem agente antimicrobiano (DB) e água. Para análise in vitro foram realizados ensaios físico-químicos (medida da densidade, pH, consistência e características reológicas); ensaio de abrasividade, avaliada em 30 espécimes de resina acrílica antes e após a escovação artificial e análise microbiológica com a formação de biofilme multiespécies (S. mutans, C. albicans e C. glabrata) sobre espécimes em resina acrílica. Estes, após contaminação, foram escovados por 60s com DR, DT, DC e DB e água (n=10). Foram empregados controles positivo (contaminado e não escovado) e negativo (sem contaminação). Para análise in vivo, seguiu-se o modelo \"crossover\" com \"washout\" de 7 dias. Os voluntários escovaram suas próteses superiores 3 vezes ao dia por 07 dias. A capacidade de remoção do biofilme foi avaliada empregando evidenciação, fotografia e quantificação com software Image Tool 3.0. Na avaliação antimicrobiana, o biofilme foi desprendido da prótese por escovação com solução salina e a suspensão resultante, semeada em meios de cultura específicos para Candida spp, S. mutans, S. aureus e bactérias Gram-negativas. As espécies de Candida foram identificadas pelo meio de cultura Chromagar e pela PCR (Polymerase Chain Reaction). Na avaliação dos dentifrícios pelos participantes foi aplicado questionário. Os resultados das características organolépticas e físico-químicas foram informados em tabelas autoexplicativas. Os dados de rugosidade foram analisados por ANOVA e os dados da ação antimicrobiana in vitro, pelo teste de Kruskal-Wallis. Para os dados das variáveis clínicas (in vivo), empregou-se teste de Friedman e o teste de Cochran. Os testes estatísticos foram realizados com p<0,05. Os dentifrícios não apresentaram diferença quanto à abrasividade (DB=0,264±0,098; DR=0,236±0,236; DT=0,265±0,116; DC=0,203±0,105), porém promoveram aumento da rugosidade comparando à água (0,027±0,004). Frente às espécies de Candida, in vitro, o DT foi o mais eficaz (p=0,00; m=1,30) seguido do DC (m=2,6), DB (m=3,26) e DR (m=3,59). Para o S. mutans houve diferença entre a água (m=3,86) e os dentifrícios (p=0,001), porém não entre estes (DB: m=0; DR: m=2,3 e DC: m=0). DT inibiu o crescimento de S. mutans. Quanto à capacidade de remoção do biofilme, não houve diferença entre os dentifrícios (p=0,055; DB: m=7,39; DR: m=7,94; DT: m=10,16; DC: m=8,14), porém houve redução do biofilme comparando ao Baseline (m=16,53). Os dentifrícios não apresentaram diferença antimicrobiana, in vivo, contra Candida spp. (p=0,495), S. mutans (p=0,497), S. aureus (p=0,845) e bactérias Gram-negativas (p=0,425). Na identificação das espécies de Candida pelo Chromagar não houve diferença quanto ao seu aparecimento independente do dentifrício (p=0,466). O resultado pela PCR foi semelhante à identificação convencional e as espécies de C. albicans, C. tropicalis e C. glabrata foram mais prevalentes, respectivamente. Na avaliação dos dentifrícios pelos participantes não houve diferença (p>0,05) entre eles para nenhuma questão. Os dentifrícios apresentaram resultados satisfatórios, apresentando potencial para uso clínico e controle do biofilme de próteses totais. / This study evaluated experimental dentifrices based on Ricinus communis (DR), Triclosan (DT) and Cloramina-T (DC) for complete denture cleaning. To in vitro analysis were performed physicochemical tests (measurement of density, pH, consistency and rheological characteristics); abrasiveness test evaluated in 30 acrylic resin specimens before and after artificial brushing and microbiological analysis with multi-species biofilm formation (Streptococcus mutans, C. albicans and C. glabrata) on the specimens of acrylic resin. This specimens were manually brushed for 60 seconds with DR, DT, DC and DB and water (n = 10). Positive controls were used (contaminated and not brushed) and negative (no contamination). To in vivo analysis the study followed the crossover model with washout of 7 days. The volunteers brushed their upper dentures 3 times daily for 07 days. The removal of biofilm capacity was evaluated employing evidenciation, photography and quantification with Image Tool 3.0 software. For the evaluation of antimicrobial activity, the biofilm was removed from the denture by brushing with saline solution and the suspension was seeded in culture media specific for Candida spp, S. mutans, S. aureus and Gram-negative bacteria. The Candida species were identified by culture medium Chromagar and PCR method (Polymerase Chain Reaction). One questionnaire was used for the dentifrices evaluation by the participants. The results of physicochemical characteristics were informed in self-explanatory tables. The roughness data were analyzed by ANOVA and antimicrobial activity in vitro data by the Kruskal-Wallis test. To the data of the clinical variables (in vivo) was used Friedman test and Cochran test. Statistical tests were performed with p<0.05. The dentifrices showed no difference in the abrasiveness (DB=0.264 ± 0.098, DR=0.236 ± 0.236, DT=0.265 ± 0.116, DC=0.203 ± 0.105), but promoted increased roughness when compared to water (0.027 ± 0.004). To Candida species, in vitro, the DT was the most effective (p=0.00, m=1.30) followed by DC (m=2.6), DB (m=3.26) and DR (m=3.59). To S. mutans there was difference between the water (m=3.86) and dentifrices (p=0.001), but these did not showed difference from each other (DB: m=0; DR: m=2.3 and DC: m=0). DT inhibited the growth of S. mutans. There was no difference among the dentifrices for biofilm removal (p=0.055; DB: m=7.39; DR: m=7.94; DT: m=10.16; DC: m=8.14), but the biofilm decreased when compared to Baseline (m=16.53). The dentifrices showed no difference antimicrobial, in vivo, against Candida spp. (p=0.495), S. mutans (p=0.497), S. aureus (p=0.845) and Gram-negative bacteria (p=0.425). In the identification of Candida species by Chromagar there was no difference in the appearance of their independent dentifrices (p=0.466). The result by PCR was similar conventional identification, and the species of C. albicans, C. tropicalis and C. glabrata were more prevalent, respectively. In the evaluation of dentifrices by the participants there was no difference (p>0.05) among them to any question. The dentifrices showed satisfactory results with potential for its specificity.

Thesis (Master of Applied Sciences in Chemistry)--Cape Peninsula University of Technology, 2018. / Maintenance of optimum wound chemistry is important to ensure timely healing of a wound. Bacterial infections impair the process of wound healing by producing toxins that alter the chemical environment in and around the wound. The imbalance in the wound chemistry prolongs healing and opens doors to opportunistic infections. Bacteria have developed resistance to conventional bactericides hence, there is need for search of new bactericides that can control bacteria in and around the wound. Therefore, new chemical or biochemical bactericides, which are not resisted by the bacteria, can be explored to control bacterial life around the wound in a bid to maintain optimum wound healing chemistry. Materials such as chitosan, zinc oxide, copper oxide and silver have showed remarkable potential as both bactericidal and wound healing agents. In this work silver, zinc oxide, and copper oxide nanoparticles (NPs) and their chitosan composites (CH-NPs) were synthesized using the chemical reduction method and simple chelation respectively to produce nanoparticles of Ag, ZnO, and CuO as well as composites of CH-ZnO, CH-Ag, CH-CuO, and CH-ZnO-Ag-CuO. Formation of the NPs was confirmed by the exhibition of characteristic peaks in UV-Visible and Fourier Transform Infrared Resonance (FTIR) spectroscopy as well as X-ray diffraction. The nanoparticles (NPs) had optical and electronic band gaps in the range 1 to 5eV indicating their semi-conductive nature. X-ray diffraction (XRD) investigations depicted the crystalline structures of the NPs to be base-centred, face-centred, and hexagonal for Ag, CuO, and ZnO respectively. Transmission electron microscopy (TEM) studies exhibited spherical, hexagonal, and rod-shaped shapes for silver, copper oxide, zinc oxide NPs respectively. Electrochemical investigations of the pure NPs indicated the existence of both the adsorption and the diffusion controlled electron transfer processes at electrode surfaces as well as fast electron transfer rate as depicted by the charge transfer coefficient and standard rate constant parameter values. FTIR spectra of CH-NPs composites depicted new excitation bands absent in spectra of both chitosan and the NPs. The spectra also indicated the deformation and absence of the amine (-NH2) and hydroxyl bands (-OH) within the CH-NPs composites. UV-Visible spectroscopy investigations of the CH-NPs composites exhibited blue-shifts of the λmax with respect to the NPs. The FTIR and UV-Visible spectra confirmed the existence of bonding between the chitosan and the NPs. The optical band gap energies of all the CH-NPs composites fell within the range of 2.0 to 4.5 eV indicating that the CH-NPs fell in the category of the semi-conducting materials after chelating with the chitosan.

A candidose bucal acomete grande número de pessoas mundialmente, sendo associada a condições como imunossupressão, radioterapia, tabagismo, higiene bucal, idade, xerostomia e uso de próteses removíveis. Uma importante abordagem terapêutica para essas infecções consiste nos medicamentos antifúngicos, que podem apresentar efeitos colaterais e resultar na resistência dos patógenos. Nesse contexto, a terapia fotodinâmica (PDT) faz-se interessante como alternativa capaz de minimizar essas limitações. Protocolos de PDT poderão ser mais facilmente assimilados à prática clínica se empregarem materiais já aprovados para uso odontológico. Sendo assim, este estudo propõe avaliar o uso de PDT com eritrosina como fotossensibilizador, irradiada por um LED azul, usando-se um modelo animal. Quarenta camundongos tiveram candidose induzida sobre o dorso da língua por meio de imunossupressão e inoculação com Candida albicans. Após estabelecimento da lesão durante cinco dias, os animais receberam um dentre quatro tratamentos possíveis: aplicação da eritrosina 5% seguida de irradiação pelo LED (E+L+); aplicação de eritrosina, somente (E+L-); salina seguida pela irradiação (EL+); e somente salina (E-L-). A fim de distinguir possíveis efeitos colaterais, os mesmos tratamentos foram aplicados em 12 camundongos sem a indução de candidose. O número de unidades formadoras de colônia de C. albicans foi contado após o tratamento, e a mucosa foi submetida à análise histológica para determinar o grau de inflamação. Os dados dos grupos foram comparados por meio de ANOVA e teste de Kruskal-Wallis, (&alpha;=0,05). Não foram detectadas diferenças significativas entre os grupos testados quanto à contagem de colônias de C. albicans e o grau de inflamação. O infiltrado inflamatório foi classificado como discreto na maioria dos casos. Os animais com candidose bucal induzida e os saudáveis que foram submetidos aplicação de eritrosina 5% e irradiação pelo LED apresentaram infiltrado inflamatório mais acentuado e lesões mais evidentes na camada epitelial, sugerindo que este protocolo ocasionou danos aos tecidos orais. / Oral candidosis affects many people worldwide and is associated with conditions such as immunosuppression, radiation, smoking, oral hygiene, age, xerostomia and use of removable prostheses. An important therapeutic approach for these infections consists of antifungal drugs, which have side effects and can result in the resistance of pathogens. In this context, photodynamic therapy (PDT) is an interesting alternative able to overcome those limitations. PDT protocols can be more easily assimilated in clinical practice if they employ materials already approved for use in dentistry. Thus, this study evaluate the PDT with the use of erythrosine as a photosensitizer, irradiated by a blue LED light, using an animal model. Forty mice had candidosis induced on the tongue by the immunosuppression and inoculation with Candida albicans. After five days that the lesion is established, the animals received one of four possible treatments: application of 5% erythrosine and irradiation by the LED (E+L+); erythrosine application, only (E+L- ); saline followed by irradiation (E-L+); and only saline (E-L-). In order to distinguish potential side effects, the same treatments were applied in 12 mice without induced candidosis. Colony-forming units (CFU) of C. albicans were counted after treatment, and the mucosa was subjected to histological analysis to determine the degree of inflammation. The data of the groups were compared using ANOVA and Kruskal-Wallis test (&alpha;=0.05). No significant difference was detected among the groups tested for the number of CFU of C. albicans and the degree of inflammation. The inflammatory infiltrate was classified as mild in most cases. Animals with induced oral candidosis and the healthy ones exhibited more pronounced inflammatory infiltrate and lesions in the epithelial layer following PDT by 5% erythrosine and irradiation by the LED light. Such findings suggest that this protocol resulted in damage to oral tissues.

Foram avaliados dentifrícios experimentais à base de Ricinus communis (DR), Triclosan (DT) e Cloramina-T (DC) para higiene de próteses totais, tendo como controle dentifrício sem agente antimicrobiano (DB) e água. Para análise in vitro foram realizados ensaios físico-químicos (medida da densidade, pH, consistência e características reológicas); ensaio de abrasividade, avaliada em 30 espécimes de resina acrílica antes e após a escovação artificial e análise microbiológica com a formação de biofilme multiespécies (S. mutans, C. albicans e C. glabrata) sobre espécimes em resina acrílica. Estes, após contaminação, foram escovados por 60s com DR, DT, DC e DB e água (n=10). Foram empregados controles positivo (contaminado e não escovado) e negativo (sem contaminação). Para análise in vivo, seguiu-se o modelo \"crossover\" com \"washout\" de 7 dias. Os voluntários escovaram suas próteses superiores 3 vezes ao dia por 07 dias. A capacidade de remoção do biofilme foi avaliada empregando evidenciação, fotografia e quantificação com software Image Tool 3.0. Na avaliação antimicrobiana, o biofilme foi desprendido da prótese por escovação com solução salina e a suspensão resultante, semeada em meios de cultura específicos para Candida spp, S. mutans, S. aureus e bactérias Gram-negativas. As espécies de Candida foram identificadas pelo meio de cultura Chromagar e pela PCR (Polymerase Chain Reaction). Na avaliação dos dentifrícios pelos participantes foi aplicado questionário. Os resultados das características organolépticas e físico-químicas foram informados em tabelas autoexplicativas. Os dados de rugosidade foram analisados por ANOVA e os dados da ação antimicrobiana in vitro, pelo teste de Kruskal-Wallis. Para os dados das variáveis clínicas (in vivo), empregou-se teste de Friedman e o teste de Cochran. Os testes estatísticos foram realizados com p<0,05. Os dentifrícios não apresentaram diferença quanto à abrasividade (DB=0,264±0,098; DR=0,236±0,236; DT=0,265±0,116; DC=0,203±0,105), porém promoveram aumento da rugosidade comparando à água (0,027±0,004). Frente às espécies de Candida, in vitro, o DT foi o mais eficaz (p=0,00; m=1,30) seguido do DC (m=2,6), DB (m=3,26) e DR (m=3,59). Para o S. mutans houve diferença entre a água (m=3,86) e os dentifrícios (p=0,001), porém não entre estes (DB: m=0; DR: m=2,3 e DC: m=0). DT inibiu o crescimento de S. mutans. Quanto à capacidade de remoção do biofilme, não houve diferença entre os dentifrícios (p=0,055; DB: m=7,39; DR: m=7,94; DT: m=10,16; DC: m=8,14), porém houve redução do biofilme comparando ao Baseline (m=16,53). Os dentifrícios não apresentaram diferença antimicrobiana, in vivo, contra Candida spp. (p=0,495), S. mutans (p=0,497), S. aureus (p=0,845) e bactérias Gram-negativas (p=0,425). Na identificação das espécies de Candida pelo Chromagar não houve diferença quanto ao seu aparecimento independente do dentifrício (p=0,466). O resultado pela PCR foi semelhante à identificação convencional e as espécies de C. albicans, C. tropicalis e C. glabrata foram mais prevalentes, respectivamente. Na avaliação dos dentifrícios pelos participantes não houve diferença (p>0,05) entre eles para nenhuma questão. Os dentifrícios apresentaram resultados satisfatórios, apresentando potencial para uso clínico e controle do biofilme de próteses totais. / This study evaluated experimental dentifrices based on Ricinus communis (DR), Triclosan (DT) and Cloramina-T (DC) for complete denture cleaning. To in vitro analysis were performed physicochemical tests (measurement of density, pH, consistency and rheological characteristics); abrasiveness test evaluated in 30 acrylic resin specimens before and after artificial brushing and microbiological analysis with multi-species biofilm formation (Streptococcus mutans, C. albicans and C. glabrata) on the specimens of acrylic resin. This specimens were manually brushed for 60 seconds with DR, DT, DC and DB and water (n = 10). Positive controls were used (contaminated and not brushed) and negative (no contamination). To in vivo analysis the study followed the crossover model with washout of 7 days. The volunteers brushed their upper dentures 3 times daily for 07 days. The removal of biofilm capacity was evaluated employing evidenciation, photography and quantification with Image Tool 3.0 software. For the evaluation of antimicrobial activity, the biofilm was removed from the denture by brushing with saline solution and the suspension was seeded in culture media specific for Candida spp, S. mutans, S. aureus and Gram-negative bacteria. The Candida species were identified by culture medium Chromagar and PCR method (Polymerase Chain Reaction). One questionnaire was used for the dentifrices evaluation by the participants. The results of physicochemical characteristics were informed in self-explanatory tables. The roughness data were analyzed by ANOVA and antimicrobial activity in vitro data by the Kruskal-Wallis test. To the data of the clinical variables (in vivo) was used Friedman test and Cochran test. Statistical tests were performed with p<0.05. The dentifrices showed no difference in the abrasiveness (DB=0.264 ± 0.098, DR=0.236 ± 0.236, DT=0.265 ± 0.116, DC=0.203 ± 0.105), but promoted increased roughness when compared to water (0.027 ± 0.004). To Candida species, in vitro, the DT was the most effective (p=0.00, m=1.30) followed by DC (m=2.6), DB (m=3.26) and DR (m=3.59). To S. mutans there was difference between the water (m=3.86) and dentifrices (p=0.001), but these did not showed difference from each other (DB: m=0; DR: m=2.3 and DC: m=0). DT inhibited the growth of S. mutans. There was no difference among the dentifrices for biofilm removal (p=0.055; DB: m=7.39; DR: m=7.94; DT: m=10.16; DC: m=8.14), but the biofilm decreased when compared to Baseline (m=16.53). The dentifrices showed no difference antimicrobial, in vivo, against Candida spp. (p=0.495), S. mutans (p=0.497), S. aureus (p=0.845) and Gram-negative bacteria (p=0.425). In the identification of Candida species by Chromagar there was no difference in the appearance of their independent dentifrices (p=0.466). The result by PCR was similar conventional identification, and the species of C. albicans, C. tropicalis and C. glabrata were more prevalent, respectively. In the evaluation of dentifrices by the participants there was no difference (p>0.05) among them to any question. The dentifrices showed satisfactory results with potential for its specificity.

Thesis (MSc (Biomedical Technology))--Cape Peninsula University of Technology, 2018. / The challenge of antimicrobial resistance has increased drastically over the years as more microorganisms are becoming resistant to the available conventional treatments. The burden of antimicrobial resistant infections is intensified by the increase in immunocompromising conditions such as HIV/AIDS and cancer. Due to this challenge, pharmaceutical companies, health sectors and researches are in search of new antimicrobial agents that can solve the problem at hand. Medicinal plants are a reliable source for drug discovery as it is estimated that 25% of modern medicine originated from plants. They have also been used traditionally as sources of medicine in the treatment of many human ailments. Plants can also be applied in the field of nanotechnology. Nanotechnology is a promising field in medicine as it has the potential to offer improved methods for disease diagnostics and therapeutics. The use of plants in nanotechnology brings about biologically friendly nanomaterials. Cotyledon orbiculata is one of the well-known and common plants of South Africa that is used in traditional medicinal practices. The nanotechnology applications as well as the antimicrobial and immunomodulatory effects of this plant were evaluated. The ability of C. orbiculata to synthesize silver nanoparticles was determined. Optimisation of silver nanoparticle synthesis using water extract of C. orbiculata was done at different conditions. The conditions evaluated include, reaction temperature (25 and 70°C), silver nitrate concentration (1 and 3mM), plant extract concentration (1.5, 3 and 6mg/ml) and reaction time. The synthesis of silver nanoparticles using this plant was successful. The optimal conditions for the synthesis of silver nanoparticles using C. orbiculata were 3mg/ml of the C. orbiculata extract, 3mM silver nitrate at a reaction temperature of 70°C for 2 hours. Under these conditions, spherical, crystalline nanoparticles with sizes of 20-40nm were produced. The antimicrobial and immunomodulatory properties of C. orbiculata extracts and silver nanoparticles were evaluated. Antimicrobial activity was evaluated against Staphylococcus aureus, Staphylococcus epidermidis, Methicillin resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa and Candida albicans, using the micro-dilution assay to determine the minimum inhibitory concentration (MIC). The results obtained revealed that all extracts of C. orbiculata have antimicrobial properties against all the microorganisms tested. The MICs of the extracts ranged from 3.13 to 50mg/ml and the MBC/MFC from 6.25 to >100mg/ml. The methanol extract exhibited better antimicrobial activity in comparison to the others extracts whereas the water extract had better antifungal properties. The chloroform extract showed the lowest activity in both antibacterial and antifungal studies. Silver nanoparticles also exhibited antimicrobial activity against all the microorganisms tested. It’s MICs against these microorganisms ranged from 5–80μg/ml and MBC/MFC from 20-160μg/ml. The silver nanoparticles were highly active than the water extract against both the bacteria and the fungi. Immunomodulatory effects of the plant extracts and silver nanoparticles were determined by evaluating cytokine production using the enzyme linked immunoassay (ELISA) assay. All the extracts and silver nanoparticles of C. orbiculata were found to have anti-inflammatory properties. The water extracts showed more anti-inflammatory activity against the cytokines than the other extracts. However the silver nanoparticles were more active than the water extract. The findings from this study confirmed that C. orbiculata have antimicrobial and immunomodulatory effects. This provided scientific evidence of the traditional use of this plant in the treatment of skin infections and inflammatory conditions.

Thilani Indunika Udayanthi Ahangama Marasinghe. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 156-168). / Abstracts in English and Chinese. / ABSTRACT (ENGLISH VERSION) --- p.I / ABSTRACT (CHINESE VERSION) --- p.IV / DECLARATION --- p.VI / ACKNOWLEDGEMENTS --- p.VII / TABLE OF CONTENTS --- p.IX / LIST OF TABLES --- p.XIII / LIST OF FIGURES --- p.XVI / LIST OF APPENDICES --- p.XVIII / LIST OF ABBREVIATIONS --- p.XIX / Chapter CHAPTER 1 - --- INTRODUCTION --- p.1 / Chapter 1.1 --- Antimicrobial resistance --- p.1 / Chapter 1.1.1 --- Global emergence of drug-resistant organisms --- p.1 / Chapter 1.1.2 --- Resistance problem in Hong Kong --- p.5 / Chapter 1.1.2.1 --- Antimicrobial resistance of bacterial isolates in hospital --- p.5 / Chapter 1.1.2.2 --- Antimicrobial resistance of bacterial isolates from community --- p.8 / Chapter 1.1.3 --- Dynamics of resistance --- p.11 / Chapter 1.1.4 --- Mechanisms of antimicrobial resistance --- p.12 / Chapter 1.1.4.1 --- Enzymatic inactivation or modification --- p.12 / Chapter 1.1.4.2 --- Alteration of target site --- p.13 / Chapter 1.1.4.3 --- Impaired permeability --- p.13 / Chapter 1.1.4.4 --- Efflux pumps --- p.14 / Chapter 1.1.4.5. --- Alteration of metabolic pathway --- p.14 / Chapter 1.1.5 --- Association between antimicrobial use and resistance --- p.16 / Chapter 1.1.6 --- Clinical and economic impact of resistance --- p.17 / Chapter 1.1.7 --- Measures to minimize resistance in healthcare setting --- p.19 / Chapter 1.2 --- Antimicrobial classes --- p.21 / Chapter 1.2.1 --- β-Lactams --- p.21 / Chapter 1.2.2 --- Glycopeptides --- p.23 / Chapter 1.2.3 --- Quinolones --- p.24 / Chapter 1.2.4 --- Oxazolidinones-Linezolid --- p.25 / Chapter 1.3 --- Antimicrobial Stewardship Program (ASP) --- p.26 / Chapter 1.3.1 --- Definition --- p.26 / Chapter 1.3.2 --- Strategies --- p.27 / Chapter 1.3.3 --- Multidisciplinary Antimicrobial Management Team --- p.29 / Chapter 1.3.4 --- Limitations --- p.30 / Chapter 1.3.5 --- Experience in ASP --- p.30 / Chapter 1.4 --- ASP in Hong Kong --- p.36 / Chapter 1.4.1 --- Implementation at Prince of Wales Hospital --- p.36 / Chapter 1.4.2 --- Targeted antimicrobials --- p.38 / Chapter 1.5 --- Extended-Spectrum β-Lactamases (ESBLs) --- p.40 / Chapter 1.5.1 --- Classification of β-lactamases --- p.40 / Chapter 1.5.2 --- Definition of ESBLs --- p.42 / Chapter 1.5.3 --- Types of ESBLs --- p.42 / Chapter 1.5.4 --- Epidemiology of ESBLs --- p.44 / Chapter 1.5.5 --- ESBL detection --- p.46 / Chapter 1.5.6 --- Risk factors for acquisition of ESBL-producing organisms --- p.49 / Chapter 1.5.7 --- Clinical and economic impact of infections caused by ESBL- producing organisms --- p.50 / Chapter 1.5.8 --- Treatment options for infections caused by ESBL-producing organisms --- p.51 / Chapter 1.5.8.1 --- Carbapenems --- p.52 / Chapter 1.5.8.2 --- Noncarbapenems --- p.54 / Chapter 1.5.8.2.1 --- "Quinolones, aminoglycosides and sulfonamides" --- p.54 / Chapter 1.5.8.2.2 --- Cephalosporins --- p.55 / Chapter 1.5.8.2.3 --- β-Lactam/β-lactamase inhibitor combinations --- p.56 / Chapter 1.6. --- Objectives of the study --- p.58 / Chapter CHAPTER 2 - --- METHODS --- p.60 / Chapter 2.1 --- Data collection --- p.60 / Chapter 2.2 --- ESBL detection at PWH --- p.60 / Chapter CHAPTER 3 - --- OBJECTIVE 1 --- p.62 / Chapter 3.1 --- Title:-The impact of an Antimicrobial Stewardship Program on broad spectrum antimicrobials within a Medical Department in a Hong Kong tertiary care hospital --- p.62 / Chapter 3.2 --- Method --- p.62 / Chapter 3.2.1 --- Study setting --- p.62 / Chapter 3.2.2 --- Study design and sample --- p.62 / Chapter 3.2.3 --- Definitions --- p.63 / Chapter 3.2.4 --- Data collection --- p.64 / Chapter 3.2.5 --- Data analysis --- p.65 / Chapter 3.2.5.1 --- Outcome measures --- p.65 / Chapter 3.2.5.2 --- Statistical analysis --- p.65 / Chapter 3.3 --- Results --- p.66 / Chapter 3.3.1 --- Patient characteristics --- p.66 / Chapter 3.3.2 --- Clinical characteristics --- p.66 / Chapter 3.3.2.1 --- Source of infection --- p.66 / Chapter 3.3.2.2 --- Severity of infection-Intervention period --- p.69 / Chapter 3.3.2.3 --- Healthcare-associated infections (HAIs) --- p.69 / Chapter 3.3.3 --- Prescribing practices --- p.71 / Chapter 3.3.3.1 --- Prescriptions reviewed and pattern of antibiotic prescription --- p.71 / Chapter 3.3.3.2 --- Indication --- p.73 / Chapter 3.3.3.2.1 --- Appropriateness of indication --- p.73 / Chapter 3.3.3.2.2 --- Appropriate indications of use-Individual targeted antimicrobials --- p.75 / Chapter 3.3.3.2.3 --- Inappropriate antimicrobial use --- p.77 / Chapter 3.3.4 --- Recommendations made and acceptance --- p.79 / Chapter 3.3.5 --- Outcome measures --- p.81 / Chapter 3.3.5.1 --- Multivariate model of appropriate antimicrobial use --- p.81 / Chapter 3.3.5.2 --- Multivariate model of all-cause mortality --- p.82 / Chapter 3.3.5.3 --- Treatment outcome-intervention period --- p.85 / Chapter 3.3.6 --- Antimicrobial consumption --- p.86 / Chapter 3.3.6.1 --- Targeted antimicrobials --- p.86 / Chapter 3.3.6.2 --- Other antimicrobials --- p.86 / Chapter 3.3.7 --- Bacterial susceptibility --- p.89 / Chapter 3.3.7.1 --- Escherichia coli --- p.89 / Chapter 3.3.7.1.1 --- Resistance rates to amoxicillin/clavulanate --- p.89 / Chapter 3.3.7.1.2 --- ESBL-producing Escherichia coli --- p.89 / Chapter 3.3.7.2 --- Methicillin resistant-Staphylococcus aureus (MRSA) --- p.92 / Chapter 3.3.7.3 --- Pseudomonas aeruginosa --- p.93 / Chapter 3.3.7.3.1 --- Susceptibility rates to targeted antimicrobials --- p.93 / Chapter 3.3.7.3.2 --- Susceptibility rates to other antimicrobials --- p.93 / Chapter 3.4 --- Discussion --- p.97 / Chapter 3.4.1 --- Background characteristics of patients who were prescribed targeted antimicrobials --- p.97 / Chapter 3.4.2 --- Healthcare-associated infections (HAIs) --- p.98 / Chapter 3.4.3 --- Impact of ASP on appropriateness of antimicrobial prescription --- p.99 / Chapter 3.4.4 --- Compliance to recommendations --- p.101 / Chapter 3.4.5 --- Clinical impact of ASP --- p.101 / Chapter 3.4.6 --- Impact of ASP on antimicrobial consumptions --- p.103 / Chapter 3.4.7 --- Impact of ASP on antimicrobial resistance --- p.105 / Chapter 3.4.8 --- Influential factors associated with appropriate antimicrobial use --- p.108 / Chapter 3.4.9 --- Limitations --- p.109 / Chapter 3.4.10 --- Areas for further evaluation --- p.111 / Chapter CHAPTER 4 - --- OBJECTIVE II --- p.114 / Chapter 4.1 --- Title:-Treatment outcome and factors affecting treatment outcome of patients with bacteremia due to extended-spectrum β-lactamases-producing organisms receiving carbapenems or β-lactam/β-lactamase inhibitor combinations --- p.114 / Chapter 4.2 --- Method --- p.114 / Chapter 4.2.1 --- Study setting --- p.114 / Chapter 4.2.2 --- Study design and sample --- p.114 / Chapter 4.2.3 --- Definitions --- p.115 / Chapter 4.2.4 --- Data collection --- p.117 / Chapter 4.2.5 --- Data analysis --- p.118 / Chapter 4.2.5.1 --- Outcome measures: --- p.118 / Chapter 4.2.5.2 --- Statistical analysis: --- p.118 / Chapter 4.3 --- Results --- p.119 / Chapter 4.3.1 --- Patient characteristics --- p.120 / Chapter 4.3.2 --- Predisposing factors --- p.120 / Chapter 4.3.3 --- Clinical characteristics --- p.122 / Chapter 4.3.3.1 --- Type and source of infection --- p.123 / Chapter 4.3.3.2 --- Severity of illness markers --- p.123 / Chapter 4.3.4 --- Outcome measures --- p.125 / Chapter 4.3.4.1 --- Treatment outcome and reasons for therapeutic failure --- p.125 / Chapter 4.3.4.2 --- Factors associated with therapeutic failure --- p.127 / Chapter 4.3.4.2.1 --- Univariate analysis of variables to be associated with therapeutic failure --- p.127 / Chapter 4.3.4.2.2 --- Multivariate model of treatment failure --- p.129 / Chapter 4.3.4.3 --- Factors associated with all-cause mortality --- p.130 / Chapter 4.3.4.3.1 --- Univariate analysis of variables to be associated with all-cause mortality --- p.130 / Chapter 4.3.4.3.2 --- Multivariate model of all-cause mortality --- p.133 / Chapter 4.3.5 --- Subgroup analysis --- p.134 / Chapter 4.3.5.1 --- Carbapenem versus Cefoperazone/sulbactam --- p.134 / Chapter 4.3.5.2 --- Carbapenem versus Piperacillin/tazobactam --- p.141 / Chapter 4.3.5.3 --- Carbapenem versus Amoxicillin/clavulanate --- p.144 / Chapter 4.3.5.4 --- Comparison of treatment outcome --- p.147 / Chapter 4.4 --- Discussion --- p.148 / Chapter 4.4.1 --- Predisposing factors --- p.148 / Chapter 4.4.2 --- Treatment outcome --- p.149 / Chapter 4.4.3 --- Limitations and areas for further study --- p.153 / Chapter CHAPTER 5 - --- CONCLUSIONS --- p.154 / REFERENCES --- p.156 / APPENDICES --- p.169

Thesis (M.Sc. (Pharmacology)) -- University of Limpopo, 2018. / Refer to the document

Venoms, toxins and host-defence systems constitute rich sources of biologically active molecules, many of which have enormous therapeutic and biotechnological potential. In particular, peptides are often a significant component of these chemical arsenals, and are fundamentally important as biological effector molecules. The research presented in this thesis is centred on the isolation and investigation of peptides from both frogs and spiders, and endeavours to probe the important structural and mechanistic features of these bioactive compounds. The skin peptide profiles of interspecific hybrids between the green tree frog Litoria caerulea and the magnificent tree frog Litoria splendida have been investigated in a ninemonth survey. Fourteen peptides were characterised primarily using mass spectrometry, of which three had not been identified previously in the skin secretions of either parent. A number of these peptides are antibacterial agents, while others effectively inhibit the formation of nitric oxide by neuronal nitric oxide synthase. Implications for the genetics and expression of amphibian dermal peptides are also discussed. The majority of frogs of the genus Litoria contain at least one peptide in their glandular secretion capable of inhibiting the formation of nitric oxide by the enzyme neuronal nitric oxide synthase. This was proposed to occur by preventing the association of the regulatory cofactor, Ca²⁺ -calmodulin, with its binding site on the enzyme. Non-covalent binding of the amphibian peptides to calmodulin in the presence of Ca²⁺ has been confirmed using electrospray ionisation mass spectrometry, by the observation of complexes in the gas phase with a 1 : 1 : 4 calmodulin / peptide / Ca²⁺ stoichiometry. In addition, the structure and binding interactions of caerin 1.8, a potent nitric oxide synthase inhibitor, have been further probed using mass spectrometry and nuclear magnetic resonance spectroscopy techniques. Recently a number of small, disulfide - containing neuropeptides of the signiferin and riparin families have been characterised from the skin secretion of frogs of the Crinia genus. Of these, signiferin 1 and riparin 1.1 are both ten residue peptides with similar primary sequences, however appear to have a significantly different spectrum of bioactivity. Although both act at cholecystokinin-2 receptors, signiferin 1 is smooth muscle active while riparin 1.1 is not, and instead causes proliferation of lymphocytes. The three-dimensional structures of these peptides were determined using nuclear magnetic resonance spectroscopy and restrained molecular dynamics calculations. Both signiferin 1 and riparin 1.1 adopt β - turn type conformations, however differences in these structures may be responsible for the variation in biological activity noted for these peptides. The dermal secretions of most Australian frogs contain at least one broad-spectrum peptide antibiotic, and often a series of peptides with differing activity to afford greater protection against microbial pathogens. Solid state nuclear magnetic resonance spectroscopy studies were carried out to investigate the interaction of a number of these antibacterial peptides with anionic model membranes, and the results are compared with work previously reported using neutral lipids. It appears the peptides may have a different mode of interaction with the membranes depending upon the charge of the lipid head group. The cupiennin 1 peptides have been identified in the venom of the neotropical wandering spider, Cupiennius salei, and demonstrate potent wide-spectrum antibacterial activity. Primary sequence analysis of these peptides suggests a unique amphipathic structure distinctly different from that of other potentially helical cationic antimicrobial peptides isolated thus far. Using nuclear magnetic resonance spectroscopy and restrained molecular dynamics calculations, cupiennin 1a was found to adopt an α- helical structure with a flexible central hinge region in membrane mimicking solvents. Following this, nuclear magnetic resonance spectroscopy methods were used to further probe the antibacterial and the newly identified neuronal nitric oxide synthase inhibitory activity of this peptide. / Thesis (Ph.D.) -- University of Adelaide, School of Chemistry and Physics, Discipline of Chemistry, 2006