M. Tech. (Chemistry, Department of Chemistry), Vaal University of Technology / Infectious diseases, a group of illnesses caused by specific pathogens or its toxins is a leading cause of death globally. Treatment with antibiotics is a key intervention in the control and management of many infectious disease. However, the increasing incidence of antibiotics failure, due to the emergence of drug resistant pathogens, is rendering the use of antibiotics chemotherapy ineffective. A possible solution is to synthesize new compounds with broad spectrum characteristics and superior drug performances as alternative to conventional antibiotics. Schiff Bases are biologically active ligands. They form metal complexes with superior biological activities. This research aims to synthesize some Schiff Base metal complexes and investigate their biological effects on Staphylococcus aureus and Enterococcus faecalis. Metal acetylacetonates of Vanadium, Copper, Cobalt, Zinc, Magnesium, Manganese, Cadmium, Nickel and Iron were synthesized and characterized by Fourier transform infrared spectroscopy. Four Schiff bases, LI, L2, L3 and L4 were also synthesized by the condensation of 4- (diethylamino)-2-hydroxybenzaldehyde with 4-nitrobenzohydrazide and 4-methoxybenzohydrazide to form L1 and L2. 4-(dimethylamino) benzaldehyde was reacted with 4-nitrobenzohydrazide and 4-methoxybenzohydrazide to form L3 and L4 respectively. The Schiff base ligands were then reacted with synthesized Vanadium, manganese, cobalt and magnesium acetylacetonates to form Schiff base complexes (SBC 1A to 4D). Schiff bases ligands and complexes were characterized by FT-IR, 1H-NMR, 13C-NMR, TGA and DTA. Fourier Transform infrared spectroscopy (FTIR) of the acetylacetonates showed the formation of metal acetylacetonates as characterized by the absence of the carbonyl stretching n(C=O) vibration in metal acetylacetonate spectra as compared to pure acetylacetone. Metal acetylacetonates also showed the presence of metal oxygen vibration frequency, n(M-O-C), in the spectra obtained. Thermogravimetric analysis (TGA) and Derivative or Differential Thermogravimetric analysis (DTA) of the Schiff base ligands showed the presence of a single decomposition product in L1, L2, L3 and L4 indicating the formation of a single reaction product while those of Schiff base complexes showed the formation of several decomposition products. Proton and carbon thirteen Nuclear Magnetic Resonance (1H- and 13C-NMR) spectroscopy of the Schiff base ligands indicated the presence of hydrogen and carbon-13 in different environments. The chemical shifts of the hydrogens and carbon-13 provided evidence that Schiff base ligands were formed. The strongest evidence is the presence of the azomethine hydrogen and carbon in the spectra of the Schiff base ligands. The presence of aromatic hydrogens and carbon at chemical shift environments found in literature also confirmed the formation of Schiff base ligand. The NMR spectra of Schiff base complexes showed the presence of azomethine (HC=N) and aromatic hydrogens at expected chemical shifts. The synthesized Schiff bases and their corresponding metal complexes were screened for their invitro antibacterial activities against two Gram-positive (Staphylococcus aureues and Enterococcus feacalis) bacterial strains by the Agar-well diffusion methods.The ligands and complexes were tested against confirmed S. aureus and E. faecalis strains and only 4 exhibited antimicrobial activities. The ligands and complexes were effective against the S. aureusand E. faecalis isolates. / VUT

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / Este trabalho descreve algumas das pesquisas multidisciplinares realizadas pelo Departamento de FÃsica da Universidade Federal do Cearà (UFC), envolvendo o aproveitamento de resÃduos e a utilizaÃÃo da microscopia de forÃa atÃmica (AFM) na caracterizaÃÃo de estruturas biolÃgicas. TrÃs resÃduos foram estudados: o bagaÃo do caju, as cinzas de carvÃo mineral e as conchas de mexilhÃo Perna perna. No primeiro, foi feita a caracterizaÃÃo das cinzas originadas da queima do pedÃnculo do caju, destacando os compostos gerados neste processo: KHCO3 e K2SO4. Ambos sÃo importantes na indÃstria farmacÃutica e na produÃÃo de adubos fosfatados. No segundo, foi demonstrado o uso das cerÃmicas produzidas a partir das cinzas volantes de carvÃo mineral originadas da termelÃtrica Presidente MÃdici (RS), como substratos para a imobilizaÃÃo da invertase responsÃvel pela produÃÃo de aÃÃcar invertido. Esta aplicaÃÃo tem uso direto na produÃÃo de bebidas, medicamentos e cosmÃticos. Finalmente no terceiro, foram estudadas as alteraÃÃes na composiÃÃo, topografia da superfÃcie e dureza das conchas de mexilhÃo Perna perna tratadas termicamente. O nÃcar (ou superfÃcie perolada) de mexilhÃes tem sido usado como biomaterial na regeneraÃÃo Ãssea, tendo que sofrer processos de esterelizaÃÃo (normalmente tÃrmicos). Por isso, a importÃncia do estabelecimento de regiÃes de estabilidade mecÃnica, estrutural e composicional durante estes processos. No uso do microscÃpio de forÃa atÃmica para estudar estruturas biolÃgicas, destacou-se a importÃncia desta tÃcnica na caracterizaÃÃo do desenvolvimento de biofilmes de Enterococcus faecalis, freqÃentemente encontrada em casos clÃnicos; e a anÃlise nanoestrutural da esporopolinina de grÃos de pÃlen de Ilex Paraguarinsis St. Hill. A esporopolinina à um dos biopolÃmeros mais resistente que existe, sendo do interesse crescente dos cientistas e engenheiros de materiais.

Next Generation Sequencing (NGS) is a new technology that has revolutionized the way we study living organisms. Where previously only a few genes could be studied at a time through targeted direct probing, NGS offers the possibility to perform measurements for a whole genome at once. The drawback is that the amount of data generated in the process is large and extracting useful information from it requires new methods to process and analyze it. The main contribution of this thesis is the development of a novel experimental method coined tagRNA-seq, combining 5’tagRACE, a previously developed technique, with RNA-sequencing technology. Briefly, tagRNA-seq makes it possible to identify the 5’ ends of RNAs in bacteria and directly probe for their type, primary or processed, by ligating short RNA sequences, the tags, to the beginnings of RNA molecules. We used the method to directly probe for transcription start and processing sites in two bacterial species, Escherichiacoli and Enterococcus faecalis. It was also used to study polyadenylation in E. coli, where the ability to identify processed RNA molecules proved to be useful to separate direct and indirect regulatory effects of this mechanism. We also demonstrate how data from tagRNA-seq experiments can be used to increase confidence on the discovery of anti-sense transcripts in bacteria. Analyses of RNA-seq data obtained in the context of these experiments revealed subtle artifacts in the coverage signal towards gene ends, that we were able to explain and quantify based Kolmogorov’s broken stick model. We also discovered evidences for circularization of a few RNA transcripts, both in our own data sets and publicly available data. Designing the tags used in tagRNA-seq led us to the problem of words absent from a text. We focus on a particular subset of these, the minimal absent words (MAWs), and develop a theory providing a complete description of their size distribution in random text. We also show that MAWs in genomes from viruses and living organisms almost always exhibit a behavior different from random texts in the tail of the distribution, and that MAWs from this tail are closely related to sequences present in the genome that preferentially appear in regions with important regulatory functions. Finally, and independently from tagRNA-seq, we propose a new approach to the problem of bacterial community reconstruction in metagenomic, based on techniques from compressed sensing. We provide a novel algorithm competing with state-of-the-art techniques in the field. / <p>QC 20150930</p>

SANTOS, Ricardo Pires dos. Aproveitamento de resíduos e microscopia de força atômica em materiais biológicos. 2007. 308 f. Tese (Doutorado em Física) - Programa de Pós-Graduação em Física, Departamento de Física, Centro de Ciências, Universidade Federal do Ceará, Fortaleza, 2007. / Submitted by Edvander Pires (edvanderpires@gmail.com) on 2015-05-25T21:29:16Z No. of bitstreams: 1 2007_tese_rpsantos.pdf: 5997888 bytes, checksum: d6004e303ddc73c35d5f9a89c5c3c2a7 (MD5) / Approved for entry into archive by Edvander Pires(edvanderpires@gmail.com) on 2015-05-27T18:56:00Z (GMT) No. of bitstreams: 1 2007_tese_rpsantos.pdf: 5997888 bytes, checksum: d6004e303ddc73c35d5f9a89c5c3c2a7 (MD5) / Made available in DSpace on 2015-05-27T18:56:00Z (GMT). No. of bitstreams: 1 2007_tese_rpsantos.pdf: 5997888 bytes, checksum: d6004e303ddc73c35d5f9a89c5c3c2a7 (MD5) Previous issue date: 2007 / Este trabalho descreve algumas das pesquisas multidisciplinares realizadas pelo Departamento de Física da Universidade Federal do Ceará (UFC), envolvendo o aproveitamento de resíduos e a utilização da microscopia de força atômica (AFM) na caracterização de estruturas biológicas. Três resíduos foram estudados: o bagaço do caju, as cinzas de carvão mineral e as conchas de mexilhão Perna perna. No primeiro, foi feita a caracterização das cinzas originadas da queima do pedúnculo do caju, destacando os compostos gerados neste processo: KHCO3 e K2SO4. Ambos são importantes na indústria farmacêutica e na produção de adubos fosfatados. No segundo, foi demonstrado o uso das cerâmicas produzidas a partir das cinzas volantes de carvão mineral originadas da termelétrica Presidente Médici (RS), como substratos para a imobilização da invertase responsável pela produção de açúcar invertido. Esta aplicação tem uso direto na produção de bebidas, medicamentos e cosméticos. Finalmente no terceiro, foram estudadas as alterações na composição, topografia da superfície e dureza das conchas de mexilhão Perna perna tratadas termicamente. O nácar (ou superfície perolada) de mexilhões tem sido usado como biomaterial na regeneração óssea, tendo que sofrer processos de esterelização (normalmente térmicos). Por isso, a importância do estabelecimento de regiões de estabilidade mecânica, estrutural e composicional durante estes processos. No uso do microscópio de força atômica para estudar estruturas biológicas, destacou-se a importância desta técnica na caracterização do desenvolvimento de biofilmes de Enterococcus faecalis, freqüentemente encontrada em casos clínicos; e a análise nanoestrutural da esporopolinina de grãos de pólen de Ilex Paraguarinsis St. Hill. A esporopolinina é um dos biopolímeros mais resistente que existe, sendo do interesse crescente dos cientistas e engenheiros de materiais.

The efficacy of the sodium hypochlorite and chlorhexidine over the Enterococcus faecalis present in endodontic infections was evaluated in longitudinal studies through a systematic review. Bibliographic catalogue sources, electronically identified as MEDLINE (http://www.ncbi.nlm.nih.gov/PubMed), from 1966 until January 1st, and Cochrane Library on the same period, were used. On the searching strategy, the following combination of keywords were used faecalis and sodium hypochlorite or faecalis and chlorhexidine or faecalis and root canal infections or faecalis and endodontics infections or faecalis and root canal irrigants or faecalis and irrigant solution or faecalis and endodontics irrigants or faecalis and intracanal irrigant. The studies were selected by two independent reviewers that determined the inclusion and exclusion criteria. The search presented 229 related articles, with 6 of these as literature review articles, 39 articles were related with in vivo studies (humans or animals), and 189 included in vitro studies. From the 39 in vivo studies, 5 studies satisfied the inclusion criteria. The methodological structure of the included studies prohibited the combination of results. The efficacy of the sodium hypochlorite and chlorhexidine over the E. faecalis was demonstrated in vitro by direct contact test. On the studies involving contaminated dentin, either the sodium hypochlorite or the chlorhexidine were inefficient. On the 5 studies included, from the total of 159 teeth with endodontic infections primary or secundary, the E. faecalis was detected initially in 16 teeth by PCR and 42 by culture, and after the sanitization process in 11 teeth by PCR and 12 by culture. It was observed the absence of longitudinal studies in humans about the efficacy of chlorhexidine over the E. faecalis. The sanitization process with the emptying, enlargement and action of the sodium hypochlorite reduces the remaining endodontic microbiota, what certainly potentiates the action of the intracanal dressing and favors a higher level of success of the endodontic treatment. / Avaliou-se em estudos longitudinais a eficácia do hipoclorito de sódio e da clorexidina sobre o Enterococcus faecalis presente em infecções endodônticas, através de revisão sistemática. Fontes de catalogação bibliográfica identificadas eletronicamente por MEDLINE (http://www.ncbi.nlm.nih.gov/PubMed), a partir de 1966 até 01 de janeiro de 2007 e Cochrane Library no mesmo período. Na estratégia de busca empregou-se a combinação dos unitermos faecalis and sodium hypochlorite ou faecalis and chlorhexidine ou faecalis and root canal infections ou faecalis and endodontics infections ou faecalis and root canal irrigants ou faecalis and irrigant solution ou faecalis and endodontics irrigants ou faecalis and intracanal irrigant. Os estudos foram selecionados por dois revisores, independentes, que, determinaram os critérios de inclusão e exclusão. A busca apresentou 229 artigos relacionados, sendo que destes 6 artigos eram de revisão de literatura, 39 artigos relacionavam-se com estudos in vivo (humanos ou animais), e 189 incluíam estudos in vitro. Dos 39 estudos in vivo 5 estudos satisfizeram os critérios de inclusão. A estruturação metodológica dos estudos incluídos inviabilizou a combinação de resultados. A eficácia do hipoclorito de sódio e da clorexidina sobre o E. faecalis foi demonstrada in vitro por teste de contato direto. Nos estudos envolvendo dentina contaminada, tanto o hipoclorito de sódio quanto a clorexidina mostram-se ineficazes. Nos 5 estudos icluídos, do total de 159 dentes com infecções endodônticas primárias ou secundárias, detectou-se o E. faecalis no início do tratamento em 16 dentes por PCR e 42 por cultura; e após o processo de sanificação em 11 por PCR e 12 por cultura. Observou-se ausência de estudos longitudinais em humanos da eficácia da clorexidina sobre o E. faecalis. O processo de sanificação coadjuvado pelo esvaziamento, alargamento e ação do hipoclorito de sódio reduz a microbiota endodôntica remanescente, o que certamente potencializa a ação da medicação intracanal e favorece um maior nível de sucesso do tratamento endodôntico. / Mestre em Odontologia

No description available.

No description available.

Quorum sensing molecules have become a recent focus of study to learn if and how they can be used, both on their own and in conjecture with current antimicrobial methods, as a means of bacterial control. One such quorum sensing molecule is the sesquiterpene alcohol, Farnesol, which is synthesized and released by the fungus, Candida albicans. In most in-vivo cases, our laboratory has shown that Alcaligenes faecalis overtakes C. albicans, preventing its growth. However, as a way to counteract this inhibitory effect, Farnesol may be one way that Candida has found to fight back. In this study, we focused on the inhibitory properties of Farnesol for growth and motility of A. faecalis, as well as, the molecule’s ability to prevent Alcaligenes from creating biofilms and/or degrading them once they have already been established. Our experiments show evidence that Farnesol is able to inhibit both the growth and motility of A. faecalis, and determination of the specific concentrations of Farnesol needed to see the largest effects on A. faecalis biofilms. Our hope is that in future studies, we will be able to add varying concentrations of the Farnesol to known and widely used antibiotics in order to increase the effectiveness of antibiotics against bacterial strains, both in the Alcaligenes genus and in other genus, that have previously been considered “antibiotic resistant”.

Magister Chirurgiae Dentium - MChD / When faced with a failing or failed root treatment, the dentist must decide whether the tooth can be retreated and saved or extracted. The dentist's decision to retreat is often based on the x-ray presenting a failing root treatment. The dentist must be aware that there might be a number of factors that have contributed to the failure and which may preclude, following retreatment, a successful long term clinical function. The current study has been made to determine those factors that may influence the prognosis in order to assist the clinician in advising the patient of the best course of treatment. A literature review was made to determine and identify these factors and explain their relevance and influence on the healing process. The current study included identifying the factors described in the literature review and noting their influence on the prognosis following non-surgical retreatment. Retreatment of failed root treated teeth requires special knowledge and skill from the clinician in order to correct and manage the case. The current study was made in a clinical setting and compared results of retreatment with two types of rotary files on the market: progressive or variable taper (Pro Taper) with constant non-ISO 06 taper (K3). Clinical signs and symptoms were noted at the patient's presentation and following recalls at 1, 4 months and 1 year. The results were recorded and statistically analysed and the results were discussed. The results showed that out of 81 patients 10cases of retreatment were considered to have failed and 68 cases were considered to have been successful. Three patients did not return for their assessments and were therefore not considered in further results. There was a statistically significant (p<0.1 0) recording of deep periodontal pockets associated with teeth with failing root treatments (40%) and (13%) in the "Success" group. The two estimated proportions of "Sinus" present (60%) in the "Failure" group and 10% in the 'Success' group were significantly different (p<0.01). "Sinus present" in the "Success group" means in the initial clinical assessment before retreatment was initiated. The presence of a sinus at the One Year follow up signified a failure of the root retreatment (p<0.001). The two estimated proportions of "Occlusion" present (80% and 99%) in the "Failure" and "Success" group were significantly different (p<0.05). Therefore, teeth in "occlusion" were more within the "Success" group. 70% of those teeth that failed had pretreatment apical rarefactions of greater than 6mm diameter; whereas 76.5% of successful retreatments had areas less than 6mm diameter. The differences were significant according to Fisher's Exact Test (p<0.01). 44% of failed cases had areas of rarefaction described as "diffuse"; and 56% of failed cases had areas that were described as "well-defined". 95% of cases that were successful had areas described as "diffuse" and the rest were "welldefined". The differences between the success and failure categories were statistically significant (p<0.0 1). The two estimated proportions of "Post present" (0% and 31%) in the "Failure" and "Success" groups were significantly different (p<0.1 0). Therefore, the "Post was present" in many more cases within the "Success" group than in the "Failure" group. There was no difference between the Median "Crown/Root" ratios of the "Failure" (Median = 0.595) or "Success" groups (Median = 0.662) (Wilcoxon Test, p>O.10). Teeth with longer roots tend to lead to failure, however there was a considerable overlap between the distributions. Therefore the finding is that the Median length of the roots of the "Failures" is longer than that of the "Successes". (Wilcoxon Rank Sum Test, p-value = 0.0628). The results also indicated that previous short root filling preparation contributes to the final success of retreatment (Fisher Exact Test, p<0.05). There was a significant difference between the distribution of the "Failure" and "Success" (88.2%) groups (Fisher Exact Test, p<O.OI) in those cases with initial short obturated fillings. When comparing the outcome following the use of the two types of rotary files it was found that the "Successes" with K3 File (35 out of 41) was 85%; and with Protaper File (32 out of 36) 89%. The "Success" rate certainly was not different between the two file types. The conclusions drawn from the current study was not significantly different from those in the literature review and the overall results were of a similar nature with some minor changes. However it is clear that non-surgical root retreatment offers a good prognosis and should be included as an option for failed or failing root treatment.

Diss. (sammanfattning) Linköping : Linköpings universitet, 2005. / Härtill 5 uppsatser.