Periodontitis is an inflammatory disease of the oral cavity induced by anaerobic bacteria, that remains to be the primary cause of tooth loss in adults worldwide. Finding an anti-microbial therapeutic to selectively target periodontal pathogens has proven to be difficult, and current treatment modalities only provide a transient benefit. Amixicile is a non-toxic, readily bioavailable novel antimicrobial that targets strict anaerobes through inhibition of the activity of Pyruvate Ferredoxin Oxidoreductase (PFOR), a major enzyme mediating oxidative decarboxylation of pyruvate, a critical step in metabolism. Our study aimed to evaluate the efficacy of amixicile in inhibiting the growth of bacteria harvested from the complex sub-gingival biofilm of patients with chronic periodontitis. We hypothesize that amixicile will selectively inhibit pathogenic anaerobic bacteria collected from patients, with the same efficacy as metronidazole, the current accepted treatment modality. Plaque samples were harvested from patients with severe chronic periodontitis and cultured under anaerobic conditions. The microbiomes were grown in the presence of amixicile and metronidazole and the growth was compared to that of bacteria grown in the absence of the antimicrobials. Following 24 hour incubation, bacterial DNA was isolated and bacterial quantity was evaluated by quantitative PCR (qPCR) using primers specific for 12 bacterial species: P. gingivalis (Pg), P. intermedia (Pi), F.nucleatum (Fn), S.gordonii (Sg), S. anginosus (Sa), V. atypical (Va), L. acidophilus (La), A.actinomycetemcomitans (Aa), T.denticola (Td), S.mutans (Sm), S.sanguis (Ss), and 16s. Individual qPCR runs were combined to represent an overall average of CT value differences. Amixicile treatment groups exhibited statistical significant reductions (PP. intermedia, F. nucleatum and Veillonella atypical. When comparing amixicile to metronidazole, amixicile performed with similar efficacy with the largest effect seen for PFOR bacteria. Our conclusion supports amixicile as a potent inhibitor of anaerobic bacteria, and could be a potential new therapeutic antimicrobial in the treatment of periodontal disease

Ces travaux de thèse décrivent la synthèse de trente-quatre nouveauxdérivés de sulfanyl et de sulfonyl chalcones et de trente-quatre nouveaux dérivés dumétronidazole, ainsi que leurs évaluations biologiques en tant que possibles agentsantipaludiques et leishmanicides. L'évaluation antimalarique in vitro sur la formationde la β-hématine a montré que douze de ces dérivés possèdent une activitéinhibitrice supérieure à 80%. In vivo, deux composés ont conduit à une diminution dela parasitémie au quatrième jour après infection et à une augmentation significativedu temps de survie chez la souris. Dans le cas de l’évaluation leishmanicide in vitro,trois composés ont montré une activité inhibitrice sur la croissance despromastigotes des espèces L. mexicana et L. braziliensis. Les composés les plusactifs sont des dérivés de type benzoate possédant des substituants hydroxyles surles positions 3,4,5 et 3,4 du cycle benzénique. / This research work describes the chemical synthesis of thirty-four newsulfanyl and sulfonyl chalcone derivatives, and thirty-four new metronidazolederivatives, as well as their biological assays as antimalarial and leishmanicidalagents. The antimalarial in vitro evaluation on the β-hematin formation showed thattwelve of these derivatives display an inhibitory activity higher than 80%. In vivo, twocompounds were found to decrease the parasitaemia by the fourth day after infectionand to increase significantly the survival time of mice. In the case of the in vitroleishmanicidal evaluation, three compounds showed an inhibitory activity on thegrowth of promastigotes of L. mexicana and L. braziliensis species. The most activecompounds are benzoate derivatives featuring hydroxyl substituents at the 3,4,5 and3,4 positions of the benzene ring.

Made available in DSpace on 2014-06-11T19:23:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2002Bitstream added on 2014-06-13T18:51:04Z : No. of bitstreams: 1 silva_jl_me_araca.pdf: 618579 bytes, checksum: e0b2b3e1468a5ef867cf11c6ed9aa88f (MD5) / É proposta deste trabalho avaliar as propriedades da pasta de metronidazol a 10% e lidocaína a 2% em alvéolos dentários acometidos por alveolite, em 25 pacientes atendidos pelas disciplinas de Clínica Integrada e de Cirurgia e Traumatologia Buco-Maxilo-Facial da Faculdade de Odontologia de Araçatuba – Unesp. Os parâmetros estudados foram o controle da dor nos períodos de 1, 2 e 3 dias após a instituição do tratamento da alveolite diagnosticada. A terapêutica constou de anestesia local, cuidadosa limpeza cirúrgica e irrigação intra-alveolar com solução fisiológica, seguida da aplicação da pasta preenchendo todo o alvéolo. Com base nos resultados foi possível concluir que o emprego tópico da pasta proporcionou redução da dor e não proporcionou reações adversas locais e/ou sistêmicas ao material empregado fatos que indicam o seu uso como um medicamento eficaz sendo uma opção segura para o tratamento de feridas de extrações acometidas pela alveolite e dos desconfortos causados por esta patologia. / It is proposal of this work to evaluate the properties of the ointment compounded by 10% metronidazole and 2% lidocaine in dental alveolus attacks for dry sockets, in 25 patients attended in discipline of Integrated Clinic and Surgery and Buco-Maxillo-Facial Traumatology of the Dentistry College of Araçatuba – Unesp. The studied parameter had been the control of pain, in the periods of 1, 2 and 3 days after the instituion of the treatment of the installed osteitis. The therapeutics were local anesthesia, careful surgery cleanness and alveolar irrigation with physiological solution, followed of the application of the ointment filling al the alveolus. Based on the results, it was possible to conclude that the topic use of ointment, produced positive results that recommend its use as an effective medice being a safe option on the treatment of wound extractions attacks harmed by dry socket and the discomforts caused for this pathology.

Metronidazole is a synthetic, nitroimidazole-derivative antibacterial and antiprotozoal agent (ed. McEvoy, 2001). It has been reported that crystallization occurs in aqueous suspensions of metronidazole benzoate, a bland-tasting prodrug of metronidazole, as a result of conversion from the anhydrous to the monohydrate form, thereby compromising the stability and clinical efficacy of the substance due to the particle size growth (Hoelgaard & Moller, 1983). A generic South African based pharmaceutical company commenced formulation of an aqueous metronidazole benzoate suspension and experienced problems with crystallization that occurred in products stored at 2 to 8 °C. This study aimed to continue development of the product in order to identify a formulation that prevents formation of the hydrate form of metronidazole benzoate and the accompanying crystal growth. A variety of metronidazole benzoate suspensions were manufactured on a laboratory scale using a number of natural and synthetic suspending agents, including magnesium aluminium silicate, povidone K90, xanthan gum and Avicel® RC-591 (microcrystalline cellulose and carboxymethylcellulose sodium), over a range of concentrations. Analytical quantification methods were developed and validated, and the physicochemical properties of the raw material and finished products were fully characterized. Rheological tests were performed in order to characterize the suspension flow properties. Real-time and accelerated stability studies and a temperature cycle study were conducted in accordance with the International Conference on Harmonization (ICH) guidelines. Conversion of metronidazole benzoate to the monohydrate form took place in suspensions containing xanthan gum 0.65 percent m/v under real-time and accelerated storage conditions. The suspensions containing Avicel® RC-591 were found to be physically and chemically stable after the temperature cycle and over the 12-week period whilst stored at 25 ºC / 60 percent RH and 5 ºC. The suspensions were chemically stable whilst stored at 40 ºC / 75 percent RH but showed sedimentation at this accelerated condition. The metronidazole benzoate contained in these products remained in the anhydrous state under all storage conditions and were consequently concluded to be the most stable formulations out of all the products analyzed in the current study. The suspending agent system consisting of microcrystalline cellulose and carboxymethylcellulose sodium thus shows promise in preventing the conversion of metronidazole benzoate from the anhydrate to the monohydrate form, thereby inhibited the subsequent increase in particle size due to crystal growth.

Orientador: Ana Cláudia Pavarina / Resumo: O objetivo deste estudo foi avaliar a eficácia da terapia fotodinâmica antimicrobiana associada (aPDT) ao metronidazol (MTZ) em biofilmes periodontopatogênicos. Para tal finalidade, foram realizadas as seguintes etapas: (1) determinação do tempo de adesão (24 e 48 horas) e formação de biofilme mono e duo-espécie (3, 5 e 7 dias) de Fusobacterium nucleatum (NCTC 11326) e Porphyromonas gingivalis (ATCC 33277); (2) aplicação da aPDT mediada por PDZ associada ao MTZ em biofilmes mono-espécie de F. nucleatum e P. gingivalis. Foram avaliadas diferentes concentrações do PDZ (50, 75 e 100 mg/L) e dose de luz de 50 J/cm2 (660nm). Após a aplicação da aPDT, os biofilmes foram incubados com diferentes concentrações do MTZ (MIC, 50x MIC e 100x MIC) por 24 horas. Os grupos controles positivos (L-F-) não receberam fotossensibilizador e não foram iluminados. A viabilidade dos microrganismos após os tratamentos foi avaliada por meio da contagem de UFC/ml. Os resultados demonstraram que o período de adesão de 24 horas, seguido de 5 dias de formação de biofilme foi satisfatório para a obtenção de biofilmes maduros mono-espécie. Para F. nucleatum, os resultados demonstraram que aPDT 75 mg/mL associado com MTZ 100x MIC e aPDT 100 mg/L associado com MTZ nas concentrações de 50x MIC e 100x MIC reduziu significativamente o número de UFC/mL, 2,99; 2,9 e 3,94 Log10 respectivamente. Para P. gingivalis, a redução mais significativa de UFC/mL foi obtida quando a associação de aPDT 100 mg/L e MTZ 100x MIC ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The aim of this study was to evaluate the efficacy of metronidazole (MTZ) associated antimicrobial photodynamic therapy (aPDT) on periodontopathogenic biofilms. For this purpose, the following steps were performed: (1) determination of adhesion period (24 and 48 hours) and single and duo species biofilm formation (3, 5 and 7 days) of Fusobacterium nucleatum (NCTC 11326) and Porphyromonas gingivalis (ATCC 33277); (2) Photodithazine ® (PDZ)- mediated aPDT in association with MTZ in single-specie biofilms of F. nucleatum and P. gingivalis. Different concentrations of PDZ (50, 75 e 100 mg/L) and light dose of 50 J / cm2 (660nm) were evaluated. After application of aPDT, the biofilms were incubated with different concentrations of MTZ (MIC, 50x MIC and 100x MIC) for 24 hours. Positive control groups (L-F-) received no photosensitizer and were also not illuminated. The viability of the microorganisms after the treatments was evaluated by counting CFU/ml. The results demonstrated that the 24 hours adhesion period followed by 5 days of biofilm formation was satisfactory for obtaining a mature biofilm in single-specie. For F. nucleatum, the results demonstrated that 75 mg/L aPDT associated with MTZ 100x and 100 mg/mL aPDT associated with MTZ at 50x MIC and 100x MIC concentrations significantly reduced the number of CFU/mL, 2.99; 2.9 and 3.94 Log10 respectively. For P. gingivalis, the greatest reduction of CFU/mL was obtained when the association of aPDT 100 mg/L and MTZ 100x MIC was p... (Complete abstract click electronic access below) / Doutor

Background: Metronidazole (MTZ) is an anti-oxidant and anti-inflammatory agent with beneficial therapeutic properties. The hydrophilic nature of the molecule limits its penetration across the skin. Existing commercial formulations have limitations of inadequate drug concentration present at the target site, which requires frequent administration and poor patient compliance. Objective: The aim of the current study was to develop and evaluate water in oil microemulsion of Metronidazole with higher skin retention for the treatment of inflammatory skin disorders. Methods: Pseudo ternary phase diagrams were used in order to select the appropriate ratio of sur-factant and co-surfactant and identify the microemulsion area. The selected formulation consisted of Capmul MCM as oil, Tween 20 and Span 20 as surfactant and co-surfactant, respectively, and water. The formulation was characterized and evaluated for stability, Ex vivo permeation studies and in vivo anti-inflammatory effect (carrageenan induced rat paw edema, air pouch model), anti-p-soriatic activity (mouse-tail test). Results: The particle size analyses revealed the average diameter and polydispersity index of the selected formulation to be 16 nm and 0.373, respectively. The results of ex vivo permeation studies showed statistically higher mean cumulative amount of MTZ retained in rat skin from microemul-sion, i.e., 21.90 ± 1.92 µg/cm2, which was 6.65 times higher as compared to Marketed gel (Metro-gyl gel®) with 3.29 ± 0.11 µg/cm2 (p<0.05). The results of in vivo studies suggested the microemul-sion based formulation of MTZ to be similar in efficacy to Metrogyl gel®. Conclusion: Research suggests the efficacy of the developed MTZ loaded microemulsion in the treatment of chronic skin inflammatory disorders.

Trichomonas vaginalis is a protozoan parasite responsible for causing nearly eight million cases of Trichomoniasis every year in the United States. Trichomoniasis is often an asymptomatic infection, but in some cases it does lead to mild clinical manifestions. Trichomoniasis is easily treated with a single dose of Metronidazole. Drug resistance is not common, but it is on the rise. In addition to increasing rates of drug resistance, Trichomoniasis also poses a public health threat as it has been shown to increase the risk of HIV transmission. In order to combat this emerging public health threat, we must better understand the mechanism by which metronidazole exerts its action on T. vaginalis , as well as how the parasite has responded by evolving mechanisms of drug resistance on a molecular level. In order to investigate these questions, a microarray analysis of two distinct strains of T. vaginalis , one being more virulent and slightly less metronidazole sensitive, was performed. This allowed the identification of several genes that may play a role in virulence and drug susceptibility. Once these genes were identified, their differential regulation was further confirmed by Northern Blot analysis. One of these genes, Thioredoxin Reductase (TrxR) was then cloned and transfected into T. vaginalis . After confirming expression of the HA-tagged TrxR, the cell line was then used to determine the effect of over-expression of the gene on drug sensitivity. The metronidazole IC 50 for this cell line was compared to wild type cells. Additionally, immunostaining of the transfected cells was performed to determine the localization of the HA-tagged thioredoxin reductase. The results of this investigation provide further support for the role of TrxR in metronidazole activation as well as metronidazole sensitivity. Additionally, several other genes identified as differentially regulated may play a role in virulence, and should be targeted for further investigation.

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Periodontitis is a chronic inflammatory disease caused by pathogenic bacteria residing in a complex biofilm within a susceptible host. Amixicile is a non-toxic, readily bioavailable novel antimicrobial that targets strict anaerobes through inhibition of the activity of Pyruvate Ferredoxin Oxidoreductase (PFOR), a major enzyme mediating oxidative decarboxylation of pyruvate. Our study aimed to evaluate the efficacy of amixicile, when compared to metronidazole, in inhibiting the growth of bacteria present in a microbiome harvested from patients with chronic periodontitis. Plaque samples were harvested from patients with severe chronic periodontitis and cultured under anaerobic conditions. The microbiomes were grown in the presence of amixicile and metronidazole and the growth was compared to that of bacteria grown in the absence of the antimicrobials. Following 24 hour growth the bacterial DNA was analyzed using quantitative PCR (qPCR) using primers specific for 12 bacterial species: P. gingivalis (Pg), P. intermedia (Pi), F.nucleatum (Fn), S.gordonii (Sg), S. anginosus (Sa), V. atypical (Va), L. acidophilus (La), A.actinomycetemcomitans (Aa), T.denticola (Td), S.mutans (Sm), and S.sanguis (Ss). Both drug treatment groups yielded a statistical significant reduction for several anaerobic bacteria: Pi (P