<p dir="ltr">Mycobacterium abscessus (Mab) is a type of mycobacterium that is known for its remarkable resistance to a variety of antibiotics. This pathogen poses a significant risk for individuals with weakened immune systems as it can cause skin and soft tissue infections, pulmonary disease and disseminated infections. Mab's ability to expel antibiotics through efflux pumps and form strong biofilms makes it even more challenging to treat infections. Lipids form a major part of the extracellular matrix of Mab biofilms. Efflux pumps have been shown to export lipids to the cell surface. Despite ongoing research into Mab's antibiotic tolerance, there is still much to learn about the impact of efflux pump inhibitors (EPIs) on antibiotic resistance and lipid biosynthesis during biofilm development in Mab. In this study, we investigated the impact of the EPIs; CCCP (carbonyl cyanide m-chlorophenyl hydrazone), piperine (PIP), reserpine (RES), berberine (BER), and verapamil (VER) on efflux activity, biofilm formation, antibiotic resistance, and lipid biosynthesis in Mab during planktonic and biofilm growth conditions. We found that Mab cells had a higher tolerance to EPIs in biofilm-stimulating medium and that the presence of EPIs led to a decrease in minimum inhibitory concentrations of frontline antibiotics, reduced efflux activity within Mab cells, and significantly inhibited biofilm formation. We examined the effects of EPIs that inhibited biofilm formation on lipid metabolism in Mab using radiolabeling with 14C?palmitic acid and 14C-acetic acid which are precursors of lipid biosynthesis. We observed that the EPI berberine inhibited the incorporation of 14C-palmitic acid into glycopeptidolipids in the surface lipids of planktonic cells and increased cellular glycopeptidolipid (GPL) in biofilm cells. Verapamil-treated cells showed a 55 % increase in cellular trehalose monomycolate (TMM) compared to controls. Piperine-treated cells exhibited a 50 % increase in cardiolipin. The incorporation of 14C-acetate into biofilm cells showed that piperine-treated biofilm cells showed a 146 % increase in surface glycopeptidolipids. Overall, our study enhances our understanding of lipid biosynthesis in Mab, the effects of EPIs on Mab biofilms, efflux mechanisms, and antibiotic resistance and offers insights for combating Mab-related infections.</p>

Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-08-24T13:37:53Z No. of bitstreams: 1 2011- Veronica da Silva Cardoso.pdf: 2067813 bytes, checksum: a52c401412243d162e7030dda12cdf48 (MD5) / Made available in DSpace on 2016-08-24T13:37:53Z (GMT). No. of bitstreams: 1 2011- Veronica da Silva Cardoso.pdf: 2067813 bytes, checksum: a52c401412243d162e7030dda12cdf48 (MD5) Previous issue date: 2011-04-28 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / Piperine interference (amide extracted from black pepper) added to the diet of broiler chickens experimentally intoxicated by aflatoxin B1 (mycotoxin of great importance in the poultry sector) and it?s chemoprotective capacity were the main goal of this work. The experiment was divided into two assays: (i) The first assay was carried out to determine the effects of different concentrations of piperine (0, 60, 120, 180 ppm) and it?s possible toxicity in broiler chickens diets. Ninety six male chicks (Cobb), seven days old were used, being randomly allocated into four experimental groups (n=24) during 35 consecutive days. The following parameters were evaluated: biochemical, hematological, histopathological (proventriculus, gizzard, liver, kidney), histomorphometric (small intestine) and zootecnic. The concentration of 60 ppm of piperine in the diet was safe for broilers, showing better performance of broilers on period from 36 to 42 days old. The concentration of 180 ppm caused leukopenia and concentrations of 120 and 180 ppm was observed decrease in the number of heterophils and monocytes. Hepatotoxicity was observed by elevated AST enzyme activity, histopathological changes and decreased absorption surface in the segments (jejunum and ileum) of small intestine were observed for both 120 and 180 ppm concentrations. (ii) In the second assay, 60 broilers with nine days old divided into four groups: control, piperine (60 ppm added to diet), aflatoxin B1 (0.5 mg of aflatoxin B1.Kg-1 of body weight, orally) and piperine associated aflatoxin B1, were evaluated by effect chemoprotector of piperine against toxics effects of aflatoxin B1 being evaluated for zootecnic, biochemical, histopathological and histomorphometric parameters, toxic heterophils in peripheral blood and genotoxic by comet assay and micronucleus were also determined. No changes in the performance parameters were observed after this experiment. Broiler chickens intoxicated with AFB1 (0.5 mg of aflatoxin B1.kg-1 of body weight ) showed: decreased body weight gain and increased feed conversion; reduced carcass and cuts yields; liver toxicity, with increased relative weight of the liver and heart, macroscopic variations of hepatic parenchyma and increase of liver enzymes activity; kidney enzymes increase without evidence of renal tissue damage macroscopic or microscopic; leukopenia with significant reduction of lymphocytes and heterophils; reduction in absorptive surface due to the reduction of the length and width of the villi of all studied segments of small intestine; presence of toxic heterophils. The cytotoxic and genotoxic effects of aflatoxin B1 described above were significantly reduced or absent in the group of broiler intoxicated with aflatoxin B1 and fed with with piperine. No significant difference between piperine associated aflatoxin B1 in control and piperine groups were observed. The addition of 60 ppm of piperine in the diet of broiler chickens was safe, promoting beneficial effect both in zootecnic parameters and in poultry health, preventing toxic effects of aflatoxin B1in broiler chickens. / A interfer?ncia da piperina (amida extra?da da pimenta do reino) adicionada ? ra??o de frangos de corte intoxicados experimentalmente por aflatoxina B1 (micotoxina de grande relev?ncia no setor av?cola) e sua capacidade quimioprotetora foram o principal objetivo deste trabalho. O experimento foi dividido em dois ensaios: (i) O primeiro ensaio foi realizado para determinar os efeitos de diferentes concentra??es de piperina (0, 60, 120 e 180 ppm) foram avaliados e sua poss?vel toxicidade. Noventa e seis pintos (Cobb), com 7 dias de idade foram divididos aleatoriamente em 4 grupos (n=24), por 35 dias consecutivos. Os par?metros avaliados foram: hematol?gicos, bioqu?micos, histopatol?gicos (proventr?culo, moela, f?gado e rim), histomorfom?trico (intestino delgado) e par?metros zoot?cnicos. A concentra??o de 60 ppm de piperina adicionada ? ra??o foi segura para frangos de corte, tendo ainda resultado em melhor desempenho dos frangos na fase final (36-42 dias de idade). A concentra??o de 180 ppm promoveu leucopenia e nas concentra??es de 120 e 180 ppm foi observada diminui??o do n?mero de heter?filos e mon?citos; hepatotoxicidade, com eleva??o da enzima AST e altera??es histopatol?gicas em ambas as concentra??es; diminui??o da superf?cie de absor??o nos segmentos (jejuno e ?leo) do intestino delgado, por?m, sem altera??o dos par?metros zoot?cnicos. (ii) Para o segundo ensaio com a concentra??o de 60ppm de piperina: 60 frangos com 9 dias de idade, foram divididos em 4 grupos (n=15): grupo controle, grupo aflatoxina B1 (0,5 mg aflatoxina B1.kg-1 de peso vivo por via oral), grupo piperina (60 ppm adicionada ? ra??o) e grupo piperina associada a aflatoxina B1, determinando-se a capacidade quimioprotetora da piperina sendo avaliados os par?metros zoot?cnicos, hematol?gicos, bioqu?micos, histopatol?gicos, histomorfom?tricos, os efeitos genot?xicos da aflatoxina B1 pelo teste do cometa e do micron?cleo, presen?a de heter?filos t?xicos no sangue perif?rico. Os frangos intoxicados com aflatoxina B1 (0,5 mg de aflatoxina B1.Kg-1 de peso vivo) apresentaram: diminui??o do ganho m?dio de peso e piora da convers?o alimentar; diminui??o do rendimento de carca?a e cortes; hepatotoxicidade, com aumento de peso relativo do f?gado e cora??o, varia??es macrosc?picas do par?nquima hep?tico e eleva??o das enzimas hep?ticas; aumento das enzimas renais, sem evid?ncia de les?es macrosc?picas e microsc?picas no tecido renal; leucopenia, com diminui??o significativa de linf?citos e heter?filos; diminui??o da superf?cie de absor??o em fun??o da redu??o do comprimento e largura das vilosidades de todos os segmentos estudados do intestino delgado; presen?a de heter?filos t?xicos. Os efeitos citot?xicos e genot?xicos da aflatoxina B1 foram significativamente reduzidos ou ausentes no grupo piperina associada a aflatoxina B1, sem diferen?a significativa entre o grupo controle e piperina. A ra??o de frangos de corte com 60 ppm de piperina foi segura, promovendo efeito ben?fico tanto nos par?metros zoot?cnicos avaliados, como na sanidade av?cola, por impedir os efeitos t?xicos da aflatoxina B1 em frangos de corte.

A principal forma de tratamento da doença de Alzheimer é através de inibidores sintéticos de acetilcolinesterase. Os inibidores existentes no mercado além, de terem um custo elevado e apresentarem efeitos colaterais não previnem ou curam a doença de Alzheimer, apenas retardam o seu desenvolvimento. A baixa efetividade dos tratamentos existentes e a ausência de prognóstico positivo impulsionaram no mercado uma demanda por novas formas de tratamento e/ou prevenção da doença. Neste cenário, investigar a atividade anticolinesterásica em pimentas do reino e pimenta rosa, bem como seu potencial antioxidante e composição fitoquímica são maneiras de promover tanto o conhecimento sobre estas especiarias como beneficiar o panorama de saúde pública, seja no combate a doença de Alzheimer e/ou outras pandemias existentes. Com o objetivo de avaliar o potencial destas especiarias, extratos metanólicos de pimenta preta, verde, branca e rosa foram avaliados segundo o teor de fenólicos totais, atividade antioxidante pelo método DPPH, ABTS e FRAP e atividade anticolinesterásica. Posteriormente o perfil metabolômico dos grãos e extratos de pimenta foi analisado por cromatografia líquida acoplada à espectrometria de massa. As amostras foram ionizadas por -eletrospray? operando em modo negativo e positivo. O extrato de pimenta rosa apresentou o maior teor de compostos fenólicos totais e a melhor atividade antioxidante e anticolinesterásica em comparação aos demais extratos. Dentre as pimentas do reino, a pimenta verde destacou-se com os maiores teores de compostos fenólicos e atividade antioxidante pelo método DPPH e ABTS. Já a pimenta preta mostrou os melhores resultados para as análises de atividade anticolinesterásica e atividade antioxidante pelo método FRAP. Quanto ao perfil metabolômico as amostras de pimenta foram significativamente distintas entre si. Os espectros obtidos para as amostras de grãos de pimenta foram mais ricos em metabólitos em relação às amostras de extrato em ambos os modos operacionais. O processamento das pimentas do reino induziu modificações quantitativas e qualitativas sobre a composição fitoquímica deste condimento. A pimenta rosa não apresentou nenhum possível metabólito com alto potencial discriminatório, dentre os 15 íons investigados. Em modo operacional negativo, os metabólitos presentes no extrato de pimenta verde, exceto íon de m/z 329,2081, foram responsáveis por todas as contribuições mais significativas entre os perfis metabolômicos gerados. A partir dos resultados obtidos no presente trabalho é possível afirmar que a pimenta rosa apresenta o maior potencial na redução de risco da doença de Alzheimer, dentre as pimentas investigadas. / Synthetic inhibitors of cholinesterase are the main drugs used in the treatment for Alzheimer\'s disease and besides the high cost and side effects, the current drugs available in the market do not prevent or cure Alzheimer, only retard its development. The absence of positive prognosis and limited effectiveness of existing drugs enhance the demand for new forms of the disease\'s treatment and/or prevention. In this scenario, investigating Piper nigrum and Schinus terebinthifolius peppercorns for its acetylcholinesterase and antioxidant activity, as well as its phytochemical composition, are ways to promote both knowledge about these spices and the perspective of health, either in combat of Alzheimer\'s disease and/or other existing pandemics. In order to evaluate the potential of these spices, black, green, white and pink peppers methanolic extracts were evaluated according to the total phenolic content, antioxidant activity by DPPH, ABTS and FRAP assay and anticholinesterase activity. Subsequently the metabolomic profile of the extracts and peppercorns were analyzed by mass spectrometry coupled to liquid chromatography. Samples were ionized by electrospray operating in negative and positive modes. The pink pepper (Schinus terebinthifolius) extract showed the highest content of total phenolic compounds and the best antioxidant and anticholinesterase activity compared to the other extracts. Among Piper nigrum peppercorns, green pepper stood out as the highest levels of phenolic compounds and antioxidant activity by DPPH and ABTS methods. Black pepper obtained the best results for the analysis of acetylcholinesterase activity and antioxidant activity by FRAP method. Regarding the metabolomic profiles, pepper samples are significantly different from each other. The spectrum obtained for peppercorn\'s samples were richer in metabolites compared to extract\'s samples in both operating modes. The processing induced quantitative and qualitative changes on the phytochemical composition of the peppercorns. The pink pepper did not show any possible metabolite with high discriminatory potential, of the 15 ions investigated. In the negative operating mode, the metabolites present in the extracts of green pepper, excluding m/z 329.2081 ion, were responsible for all of the most significant contributions between metabolomic profiles generated. From the results obtained in this study it is possible to affirm that pink pepper has the greatest potential to reduce Alzheimer\'s disease risk, among peppers investigated.

A principal forma de tratamento da doença de Alzheimer é através de inibidores sintéticos de acetilcolinesterase. Os inibidores existentes no mercado além, de terem um custo elevado e apresentarem efeitos colaterais não previnem ou curam a doença de Alzheimer, apenas retardam o seu desenvolvimento. A baixa efetividade dos tratamentos existentes e a ausência de prognóstico positivo impulsionaram no mercado uma demanda por novas formas de tratamento e/ou prevenção da doença. Neste cenário, investigar a atividade anticolinesterásica em pimentas do reino e pimenta rosa, bem como seu potencial antioxidante e composição fitoquímica são maneiras de promover tanto o conhecimento sobre estas especiarias como beneficiar o panorama de saúde pública, seja no combate a doença de Alzheimer e/ou outras pandemias existentes. Com o objetivo de avaliar o potencial destas especiarias, extratos metanólicos de pimenta preta, verde, branca e rosa foram avaliados segundo o teor de fenólicos totais, atividade antioxidante pelo método DPPH, ABTS e FRAP e atividade anticolinesterásica. Posteriormente o perfil metabolômico dos grãos e extratos de pimenta foi analisado por cromatografia líquida acoplada à espectrometria de massa. As amostras foram ionizadas por -eletrospray? operando em modo negativo e positivo. O extrato de pimenta rosa apresentou o maior teor de compostos fenólicos totais e a melhor atividade antioxidante e anticolinesterásica em comparação aos demais extratos. Dentre as pimentas do reino, a pimenta verde destacou-se com os maiores teores de compostos fenólicos e atividade antioxidante pelo método DPPH e ABTS. Já a pimenta preta mostrou os melhores resultados para as análises de atividade anticolinesterásica e atividade antioxidante pelo método FRAP. Quanto ao perfil metabolômico as amostras de pimenta foram significativamente distintas entre si. Os espectros obtidos para as amostras de grãos de pimenta foram mais ricos em metabólitos em relação às amostras de extrato em ambos os modos operacionais. O processamento das pimentas do reino induziu modificações quantitativas e qualitativas sobre a composição fitoquímica deste condimento. A pimenta rosa não apresentou nenhum possível metabólito com alto potencial discriminatório, dentre os 15 íons investigados. Em modo operacional negativo, os metabólitos presentes no extrato de pimenta verde, exceto íon de m/z 329,2081, foram responsáveis por todas as contribuições mais significativas entre os perfis metabolômicos gerados. A partir dos resultados obtidos no presente trabalho é possível afirmar que a pimenta rosa apresenta o maior potencial na redução de risco da doença de Alzheimer, dentre as pimentas investigadas. / Synthetic inhibitors of cholinesterase are the main drugs used in the treatment for Alzheimer\'s disease and besides the high cost and side effects, the current drugs available in the market do not prevent or cure Alzheimer, only retard its development. The absence of positive prognosis and limited effectiveness of existing drugs enhance the demand for new forms of the disease\'s treatment and/or prevention. In this scenario, investigating Piper nigrum and Schinus terebinthifolius peppercorns for its acetylcholinesterase and antioxidant activity, as well as its phytochemical composition, are ways to promote both knowledge about these spices and the perspective of health, either in combat of Alzheimer\'s disease and/or other existing pandemics. In order to evaluate the potential of these spices, black, green, white and pink peppers methanolic extracts were evaluated according to the total phenolic content, antioxidant activity by DPPH, ABTS and FRAP assay and anticholinesterase activity. Subsequently the metabolomic profile of the extracts and peppercorns were analyzed by mass spectrometry coupled to liquid chromatography. Samples were ionized by electrospray operating in negative and positive modes. The pink pepper (Schinus terebinthifolius) extract showed the highest content of total phenolic compounds and the best antioxidant and anticholinesterase activity compared to the other extracts. Among Piper nigrum peppercorns, green pepper stood out as the highest levels of phenolic compounds and antioxidant activity by DPPH and ABTS methods. Black pepper obtained the best results for the analysis of acetylcholinesterase activity and antioxidant activity by FRAP method. Regarding the metabolomic profiles, pepper samples are significantly different from each other. The spectrum obtained for peppercorn\'s samples were richer in metabolites compared to extract\'s samples in both operating modes. The processing induced quantitative and qualitative changes on the phytochemical composition of the peppercorns. The pink pepper did not show any possible metabolite with high discriminatory potential, of the 15 ions investigated. In the negative operating mode, the metabolites present in the extracts of green pepper, excluding m/z 329.2081 ion, were responsible for all of the most significant contributions between metabolomic profiles generated. From the results obtained in this study it is possible to affirm that pink pepper has the greatest potential to reduce Alzheimer\'s disease risk, among peppers investigated.

Made available in DSpace on 2015-05-14T13:21:40Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 9887169 bytes, checksum: df02b626a4888063d509afbbb46317e8 (MD5) Previous issue date: 2014-08-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This work was presented using the technique of molecular hybridization which is a classic strategy in medicinal chemistry and useful in the design of new drugs, consisting of the covalent joining of two or more fragments known pharmacophoric or already present recognized therapeutic activities. Described the technique of extraction, isolation and purification of piperine 6 with 2% yield, with the same natural molecule mostly present in black pepper, where studies have shown a variety of biological activities as analgesic, anti-inflammatory, anti-thermal, antitumor, antifungal, antichagasic, insecticide, leishmanicidal, among others. Next, was performed the synthesis of the respective piperic acid 12 obtained via basic hydrolysis with 87% yield. A series of alcohols tetrahydropyran derivatives replaced (33, 34, 37, 38, 79 and 80) were synthesized in good yields (76% -100%), with synthetic route and potent antinociceptive already described by our group research. The Prins cyclization reaction was used as key step to build diastereoselective 2,4-cis and 2,4,6-cis tetrahydropyranyl rings. Subsequently, we performed the synthesis of 6 novel hybrid molecules (64, 65, 66, 67, 68 and 69), based on the structure of an analog of piperine (piperic acid) with 6 alcohols substituted tetrahydropyran derivatives, using the classical approach molecular hybridization by Steglich esterification reaction to join the two portions with relatively good yields (42% - 78%), which was the intention enhance the analgesic activity by these two chemical entities. All molecular hybrids were characterized by spectroscopic (1H and 13C) and IR / Neste trabalho foi apresentado o uso da técnica de hibridização molecular que é uma estratégia clássica em química medicinal e bastante útil na concepção de novos fármacos, consistindo na junção covalente de dois ou mais fragmentos reconhecidamente farmacofóricos ou que já apresentem atividades terapêuticas reconhecidas. Descreveu-se a técnica de extração, isolamento e purificação da piperina 6 com 2% de rendimento, sendo a mesma uma molécula natural presente principalmente na pimenta preta, onde estudos mostraram uma série de atividades biológicas como, analgésico, antiinflamatório, antitérmico, antitumoral, antifúngico, antichagásico, inseticida, leishmanicida, dentre outras. Em seguida, foi realizado a síntese do seu respectivo ácido pipérico 12 obtido via hidrólise básica com 87% de rendimento. Uma série de derivados álcoois tetraidropiranos substituídos (33, 34, 37, 38, 79 e 80) foram sintetizados em bons rendimentos (76%-100%), com rota sintética e potente atividade antinociceptiva já descritas pelo nosso grupo de pesquisa. A reação de ciclização de Prins foi usada como etapa chave para a construção, em forma diastereosseletiva 2,4-cis e 2,4,6-cis, dos anéis tetraidropiranos. Posteriormente, realizou-se a síntese de 6 moléculas híbridas inéditas (64, 65, 66, 67, 68 e 69), baseadas na estrutura de uma análogo da piperina (ácido pipérico) com os 6 derivados álcoois tetraidropiranos substituídos, utilizando a estratégia clássica de hibridização molecular através da reação de esterificação de Steglich para unir as duas porções, com rendimentos relativamente bons (42%-78%), onde o intuito foi potencializar a atividade analgésica apresentada por estas duas entidades químicas. Todos os híbridos moleculares foram caracterizados pelas técnicas de espectroscopia (1H e 13C) e infravermelho

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Master thesis "Czech Republic and its connection to new LNG terminals - strengthening of the gas security" examines the level of gas security in the Czech Republic. Dependency of the Czech Republic on gas supplies from foreign countries is almost 100 %. Russian federation is dominant supplier with roughly 75 % of the supplies. High dependency on one exporter is considered hazardous from energy security perspective. The Czech government should strive to change and improve this situation. The diversification is considered as a useful tool to improve the gas security. Currently there are new gas projects built in neighboring countries, which may influence energy security of the Czech Republic. The study researches the impact of these new projects on the Czech Republic. Namely we focused on gas pipeline Nord Stream and its Czech connection Gazelle, which will connect North Germany and Bavaria through the Czech Republic. Second project is gas network called "the North - South Corridor" connecting Baltic and Adriatic Sea. The North - South corridor may be potentially linked up to the new LNG terminals Świnoujście in Poland or Adria in Croatia. Furthermore, there are long-lasting plans to open new "South" gas route from Caspian region to Europe. The main goal of this thesis is to explore real...