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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Amorphous polymeric drug salts as ionic solid dispersion forms of ciprofloxacin

Mesallati, H., Umerska, A., Paluch, Krzysztof J., Tajber, L. 01 June 2017 (has links)
yes / Ciprofloxacin (CIP) is a poorly soluble drug that also displays poor permeability. Attempts to improve the solubility of this drug to date have largely focused on the formation of crystalline salts and metal complexes. The aim of this study was to prepare amorphous solid dispersions (ASDs) by ball milling CIP with various polymers. Following examination of their solid state characteristics and physical stability, the solubility advantage of these ASDs was studied, and their permeability was investigated via parallel artificial membrane permeability assay (PAMPA). Finally, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the ASDs were compared to those of CIP. It was discovered that acidic polymers, such as Eudragit L100, Eudragit L100C==, Carbopol and HPMCAS, were necessary for the amorphization of CIP. In each case, the positively charged secondary amine of CIP was found to interact with carboxylate groups in the polymers, forming amorphous polymeric drug salts. Although the ASDs began to crystallize within days under accelerated stability conditions, they remained fully XCray amorphous following exposure to 90% RH at 25 oC, and demonstrated higher than predicted glass transition temperatures. The solubility of CIP in water and simulated intestinal fluid was also increased by all of the ASDs studied. Unlike a number of other solubility enhancing formulations, the ASDs did not decrease the permeability of the drug. Similarly, no decrease in antibiotic efficacy was observed, and significant improvements in the MIC and MBC of CIP were obtained with ASDs containing HPMCASC") and HPMCASCMG. Therefore, ASDs may be a viable alternative for formulating CIP with improved solubility, bioavailability and antimicrobial activity.
72

Formation and physicochemical properties of crystalline and amorphous salts with different stoichiometries formed between ciprofloxacin and succinic acid

Paluch, Krzysztof J., McCabe, T., Müller-Bunz, B., Corrigan, O.I., Healy, A.M., Tajber, L. 15 August 2013 (has links)
Yes / Multi-ionizable compounds, such as dicarboxylic acids, offer the possibility of forming salts of drugs with multiple stoichiometries. Attempts to crystallize ciprofloxacin, a poorly water-soluble, amphoteric molecule with succinic acid (S) resulted in isolation of ciprofloxacin hemisuccinate (1:1) trihydrate (CHS-I) and ciprofloxacin succinate (2:1) tetrahydrate (CS-I). Anhydrous ciprofloxacin hemisuccinate (CHS-II) and anhydrous ciprofloxacin succinate (CS-II) were also obtained. It was also possible to obtain stoichiometrically equivalent amorphous salt forms, CHS-III and CS-III, by spray drying and milling, respectively, of the drug and acid. Anhydrous CHS and CS had melting points at ∼215 and ∼228 °C, while the glass transition temperatures of CHS-III and CS-III were ∼101 and ∼79 °C, respectively. Dynamic solubility studies revealed the metastable nature of CS-I in aqueous media, resulting in a transformation of CS-I to a mix of CHS-I and ciprofloxacin 1:3.7 hydrate, consistent with the phase diagram. CS-III was observed to dissolve noncongruently leading to high and sustainable drug solution concentrations in water at 25 and 37 °C, with the ciprofloxacin concentration of 58.8 ± 1.18 mg/mL after 1 h of the experiment at 37 °C. This work shows that crystalline salts with multiple stoichiometries and amorphous salts have diverse pharmaceutically relevant properties, including molecular, solid state, and solubility characteristics. / Solid State Pharmaceutical Cluster (SSPC), supported by Science Foundation Ireland under grant number 07/SRC/ B1158.
73

Constraints on up-regulation of drug efflux in the evolution of ciprofloxacin resistance

Praski Alzrigat, Lisa January 2017 (has links)
The crucial role of antibiotics in modern medicine, in curing infections and enabling advanced medical procedures, is being threatened by the increasing frequency of resistant bacteria. Better understanding of the forces selecting resistance mutations could help develop strategies to optimize the use of antibiotics and slow the spread of resistance. Resistance to ciprofloxacin, a clinically important antibiotic, almost always involves target mutations in DNA gyrase and Topoisomerase IV. Because ciprofloxacin is a substrate of the AcrAB-TolC efflux pump, mutations causing pump up-regulation are also common. Studying the role of efflux pump-regulatory mutations in the development of ciprofloxacin resistance, we found a strong bias against gene-inactivating mutations in marR and acrR in clinical isolates. MIC and fitness measurements revealed that amino acid substitutions conferred smaller susceptibility reductions and smaller fitness costs than gene-inactivating mutations, suggesting that resistance mutations in clinical isolates are selected for high fitness rather than high resistance (Paper I and II). We asked whether the high fitness costs of marR-inactivating mutations could be ameliorated without affecting the resistance phenotype. Multiple independent lineages were experimentally evolved to select for improved growth fitness. Whole genome sequencing revealed mutations affecting marA, lon and arcA as potential compensatory pathways. For the marA and lon mutations the improved growth rate was associated with an increased susceptibility (arcA is being investigated). (Paper III). An evolution experiment selecting for ciprofloxacin resistance revealed upon whole genome sequencing the expected mutations in drug target and efflux-regulatory genes, but also in genes encoding aminoacyl-tRNA synthetases. We investigated two independently selected leuS mutations, and concluded that they contributed to ciprofloxacin resistance by activating the stringent response that in turn caused up-regulation of genes involved in efflux. However, these leuS mutations incur a high fitness cost (Paper IV). To summarize, the research findings in this thesis suggest that the potential ciprofloxacin resistome may include more genes than previously thought, but a strong selection for high fitness selectively purifies many resistance mutations from clinical isolates. In conclusion, selection for high relative fitness constrains the spectrum of mutations that survive and get fixed in clinical populations of bacteria.
74

A reatividade da fluoroquinolona ciprofloxacina com o metal de transição rutênio / The ciprofloxacin reactivity towards the ruthenium transition metal

Tanimoto, Márcia Kiyoko 03 August 2009 (has links)
Nesta dissertação são apresentadas a síntese e caracterização de duas novas substâncias, consideradas aqui como metalo-fármacos em potencial: o composto iônico (C17H19FN3O3)3[RuCl6].3H2O e o complexo [Ru(C17H17FN3O3)3].4H2O, obtidos através da reação entre RuIII e a fluoroquinona ciprofloxacina em diferentes condições de síntese (meio ácido ou neutro e refluxo, respectivamente). O espectro ESI MS em modo positivo de (C17H19FN3O3)3[RuCl6].3H2O exibiu um pico principal em m/z = 994,6 que foi atribuído ao aduto (ciprofloxacina)3.H+ em fase gasosa, enquanto [Ru(C17H17FN3O3)3].4H2O apresentou picos m/z em 1093,3 e 547,1, atribuídos aos íons [Ru(C17H17FN3O3)3].H+ e [Ru(C17H17FN3O3)3].2H+, respectivamente. Os resultados de análise térmica estão em concordância com os conteúdos de água propostos para as duas substâncias. Os espectros de absorção em meio aquoso são dominados pelas transições da ciprofloxacina na região UV. Não obstante, duas bandas foram observadas em 421 e 496 nm no caso de (C17H19FN3O3)3[RuCl6].3H2O, e atribuídas à transição de transferência de carga e à transição d-d, respectivamente; no caso de [Ru(C17H17FN3O3)3].4H2O, apenas um ombro largo em torno de 450 nm foi observado na região do Visível, tendo sido atribuído à uma transição d-d. O voltamograma cíclico deste complexo exibiu um processo quase-reversível em 0,25 V (versus EPH) enquanto o composto iônico apresentou o mesmo processo em 0,11 V, sugerindo que, neste caso, o íon central de rutênio é estabilizado no estado de oxidação III através da coordenação dos átomos de oxigênio das três unidades de ciprofloxacina. O complexo de coordenação é estável por mais de 48 horas em pH fisiológico, estomacal e intestinal. Ambos foram incubados nas condições estomacais (pH = 1,5 e temperatura = 370C) e não causaram diminuições significativas nos valores de pH. / This work presents the synthesis and characterization of two potential new metallodrugs, the ionic (C17H19FN3O3)3[RuCl6].3H2O and the coordination [Ru(C17H17FN3O3)3].4H2O compounds, by combining ruthenium (III) and the fluoroquinolone ciprofloxacin in different synthetic conditions (acid media or neutral and reflux conditions, respectively). The ESI MS (positive mode) spectrum of the ionic compound displayed a main peak at m/z = 994.6, which was assigned to the gaseous phase adduct (ciprofloxacin)3.H+, while the coordination compound featured peaks at m/z 1093.3 and 547.1 ascribed to the singly and doubly charged ions [Ru(C17H17FN3O3)3].H+ and [Ru(C17H17FN3O3)3].2H+, respectively. Thermal analysis corroborated the proposed water content for both complexes. The absorption spectra of the compounds in aqueous medium are dominated by the ciprofloxacin transitions in the UV region but two bands were observed at 421nm and 496nm for the ionic compound, assigned to a charge transfer and d-d transitions. In the case of the coordination compound only a broad shoulder around 450 nm was observed in the visible region, also assigned to a ligand field transition The cyclic voltammograms of the [Ru(C17H17FN3O3)3] complex exhibited a quasi-reversible process ascribed to the Ru(II) / (III) redox pair at -0.25 V (vs SHE) while compound (C17H19FN3O3)3[RuCl6] displayed this process at -0.11V, showing that the central ruthenium ion is stabilized in the (III) oxidation state by the coordination to the hard oxygen atoms of the ciprofloxacin ligand. The coordination compound is stable under physiological, stomachal and intestinal pH over 48 hours. Both compounds are stable incubated under stomachal conditions (pH=1.5 and 37oC) without significant pH lowering.
75

Biodegradação de sulfametoxazol e ciprofloxacino em reator anaeróbio horizontal de leito fixo / Sulfamethoxazole and ciprofloxacin biodegradation in a horizontal anaerobic immobilized sludge reactor

Chatila, Sami 22 November 2013 (has links)
O presente trabalho aborda a biodegradação de sulfametoxazol e ciprofloxacino em 2 reatores anaeróbios horizontais de leito fixo (RAHLF). Os reatores foram operados e mantidos em regime permanente com um tempo de detenção hidráulica de 16 a 17 horas com uma água residuária sintética que simula o esgoto sanitário na temperatura de 25°C. Foi avaliado o estado dos reatores como ponto de referência para os próximos passos. A contaminação com sulfametoxazol e ciprofloxacino iniciou-se, então, e o comportamento dos reatores foi avaliado. As concentrações dos antimicrobianos foram analisadas por extração em fase sólida acoplada com espectrometria de massa. Ambos antimicrobianos foram degradados pelos reatores até níveis abaixo do limite de quantificação dos métodos de análise. Utilizando os dados de DQO e as análises dos antimicrobianos, junto com dados cinéticos obtidos, foi determinado que o RAHLF tem resistência a estes compostos e concentrações até uma ordem de magnitude acima das encontradas em condições reais. A degradação do sulfametoxazol foi muito eficiente e é previsto que um RAHLF típico em operação consegue degradar mais que 99% do sulfametoxazol. A degradação do ciprofloxacino foi menos eficiente, com remoção prevista para RAHLF típico de 80% a 90%. / The present project approaches sulfamethoxazole and ciprofloxacin biodegradation in two horizontal anaerobic immobilized sludge (HAIS) reactors. The reactors were operated and maintained at dynamic stability with a hydraulic retention time of 16 to 17 hours using synthetic wastewater, which simulates domestic wastewater, at 25°C. The dynamically stable state was evaluated as a control for the following steps. The reactors were then continuously fed with synthetic wastewater contaminated with sulfamethoxazole and ciprofloxacin, independently, and their behaviors were observed. The antibiotics\' concentrations were analyzed by solid phase extraction couples with mass spectrometry. Both antibiotics were degraded in the bioreactors to below quantification limits. Using COD and antibiotic data and derived kinetic constants, it was shown that a typical operating HAIS reactor with a hydraulic retention time of 6 to 8 hours should be capable of removing over 99% of sulfamethoxazole in its influent. Ciprofloxacin removal was less efficient, but was nevertheless promising, with a removal rate of 80% to 90% in typical conditions.
76

Erradicação da Pseudomonas aeruginosa na colonização inicial em pacientes com fibrose cística: avaliação do protocolo de um centro de referência / Eradication of new onset of Pseudomonas aeruginosa in cystic fibrosis patients: evaluation of a reference center protocol

Pimentel, Barbara Riquena 15 February 2019 (has links)
Objetivo: Diversas estratégias de erradicação da Pseudomonas aeruginosa (Pa) em pacientes com fibrose cística (FC) têm sido propostas, mas poucas realizaram o tratamento em fases e incluíram crianças na primeira colonização por Pa na vida. O objetivo desse estudo é descrever a efetividade do protocolo de erradicação em fases, em crianças brasileiras com FC no primeiro aparecimento de Pa. Métodos: Estudo de vida real, retrospectivo, que avaliou os prontuários dos pacientes pediátricos submetidos ao protocolo de erradicação em um período de 8,5 anos. O protocolo de 3 fases era guiado pela cultura de via aérea, e utilizou colistimetato nebulizado e ciprofloxacino oral. Foram avaliadas as taxas de sucesso após cada fase e a acumulada. Resultados: 47 episódios de colonização por Pa foram elegíveis à erradicação. A fase 1 do protocolo foi aplicada em 29 pacientes (mediana 2,7 anos, 59% masculino, 65% com no mínimo um alelo F508del), a fase 2 em 12 e a fase 3 em 6 pacientes. A taxa de sucesso foi de 58,6% (IC 95%: 40,7 a 74,5), 50,0% (IC 95%: 25,4 a 74,6) e 66,7% (IC 95%:30,0 a 90,3), após as fases 1, 2 e 3 respectivamente. A taxa de sucesso acumulado foi de 93,1% (IC: 78,0 a 98,1). Apenas 2 pacientes tiveram falha do tratamento de erradicação. Conclusão: O primeiro aparecimento da Pa ocorreu em crianças de baixa idade. O protocolo de erradicação em fases foi efetivo com alta taxa de sucesso / Background: Although several Pseudomonas aeruginosa (Pa) eradication strategies have been proposed for Cystic Fibrosis (CF) patients, only a few have used a stepwise treatment and enrolled children in their first-onset Pa colonization. The purpose of this study is to describe the effectiveness of a multistep eradication protocol in CF Brazilian children in their first-onset Pa. Methods: This was a real life retrospective study that evaluated medical records of pediatric patients who underwent the eradication protocol in a timeframe of 8.5 years. The 3-step protocol was guided by airway culture, using inhaled colistimethate and oral ciprofloxacin. The success rate after each step, and also the cumulative success rate were evaluated. Results: During the study period, 47 Pa colonization episodes were eligible to eradication. All the 29 patients underwent protocol\'s step 1 (median 2.7 years old, 59% male, 65% with at least one F508del allele), twelve patients step 2, and six patients step 3. Success rate was 58.6% (CI 95%: 40.7 to 74.5), 50.0% (CI 95%: 25.4 to 74.6) and 66.7% (CI 95%:30.0 to 90.3), after step 1, 2 and 3 respectively. Cumulative success rate was 93.1% (CI: 78.0 to 98.1). Failure of the eradication protocol occurred in only 2 patients. Conclusion: First-onset Pa colonization occurred in very young children. The stepwise eradication protocol was effective with a high success rate
77

A reatividade da fluoroquinolona ciprofloxacina com o metal de transição rutênio / The ciprofloxacin reactivity towards the ruthenium transition metal

Márcia Kiyoko Tanimoto 03 August 2009 (has links)
Nesta dissertação são apresentadas a síntese e caracterização de duas novas substâncias, consideradas aqui como metalo-fármacos em potencial: o composto iônico (C17H19FN3O3)3[RuCl6].3H2O e o complexo [Ru(C17H17FN3O3)3].4H2O, obtidos através da reação entre RuIII e a fluoroquinona ciprofloxacina em diferentes condições de síntese (meio ácido ou neutro e refluxo, respectivamente). O espectro ESI MS em modo positivo de (C17H19FN3O3)3[RuCl6].3H2O exibiu um pico principal em m/z = 994,6 que foi atribuído ao aduto (ciprofloxacina)3.H+ em fase gasosa, enquanto [Ru(C17H17FN3O3)3].4H2O apresentou picos m/z em 1093,3 e 547,1, atribuídos aos íons [Ru(C17H17FN3O3)3].H+ e [Ru(C17H17FN3O3)3].2H+, respectivamente. Os resultados de análise térmica estão em concordância com os conteúdos de água propostos para as duas substâncias. Os espectros de absorção em meio aquoso são dominados pelas transições da ciprofloxacina na região UV. Não obstante, duas bandas foram observadas em 421 e 496 nm no caso de (C17H19FN3O3)3[RuCl6].3H2O, e atribuídas à transição de transferência de carga e à transição d-d, respectivamente; no caso de [Ru(C17H17FN3O3)3].4H2O, apenas um ombro largo em torno de 450 nm foi observado na região do Visível, tendo sido atribuído à uma transição d-d. O voltamograma cíclico deste complexo exibiu um processo quase-reversível em 0,25 V (versus EPH) enquanto o composto iônico apresentou o mesmo processo em 0,11 V, sugerindo que, neste caso, o íon central de rutênio é estabilizado no estado de oxidação III através da coordenação dos átomos de oxigênio das três unidades de ciprofloxacina. O complexo de coordenação é estável por mais de 48 horas em pH fisiológico, estomacal e intestinal. Ambos foram incubados nas condições estomacais (pH = 1,5 e temperatura = 370C) e não causaram diminuições significativas nos valores de pH. / This work presents the synthesis and characterization of two potential new metallodrugs, the ionic (C17H19FN3O3)3[RuCl6].3H2O and the coordination [Ru(C17H17FN3O3)3].4H2O compounds, by combining ruthenium (III) and the fluoroquinolone ciprofloxacin in different synthetic conditions (acid media or neutral and reflux conditions, respectively). The ESI MS (positive mode) spectrum of the ionic compound displayed a main peak at m/z = 994.6, which was assigned to the gaseous phase adduct (ciprofloxacin)3.H+, while the coordination compound featured peaks at m/z 1093.3 and 547.1 ascribed to the singly and doubly charged ions [Ru(C17H17FN3O3)3].H+ and [Ru(C17H17FN3O3)3].2H+, respectively. Thermal analysis corroborated the proposed water content for both complexes. The absorption spectra of the compounds in aqueous medium are dominated by the ciprofloxacin transitions in the UV region but two bands were observed at 421nm and 496nm for the ionic compound, assigned to a charge transfer and d-d transitions. In the case of the coordination compound only a broad shoulder around 450 nm was observed in the visible region, also assigned to a ligand field transition The cyclic voltammograms of the [Ru(C17H17FN3O3)3] complex exhibited a quasi-reversible process ascribed to the Ru(II) / (III) redox pair at -0.25 V (vs SHE) while compound (C17H19FN3O3)3[RuCl6] displayed this process at -0.11V, showing that the central ruthenium ion is stabilized in the (III) oxidation state by the coordination to the hard oxygen atoms of the ciprofloxacin ligand. The coordination compound is stable under physiological, stomachal and intestinal pH over 48 hours. Both compounds are stable incubated under stomachal conditions (pH=1.5 and 37oC) without significant pH lowering.
78

Avalia??o de novas dietas e o efeito da adi??o de antibi?ticos no desenvolvimento de Chrysomya albiceps (Wiedemann, 1819) e Chrysomya putoria (Wiedemann, 1830) (Diptera: Calliphoridae) / Assesment of new diets and the effect of adding antibiotics on calliphorid development (Diptera)

FERRAZ, Adriana Cristina Pedroso 02 May 2012 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-05-16T17:27:57Z No. of bitstreams: 1 2012 - Adriana Cristina Pedroso Ferraz.pdf: 2396072 bytes, checksum: 4c8224201e7dfca3888239f1edd74e0f (MD5) / Made available in DSpace on 2017-05-16T17:27:57Z (GMT). No. of bitstreams: 1 2012 - Adriana Cristina Pedroso Ferraz.pdf: 2396072 bytes, checksum: 4c8224201e7dfca3888239f1edd74e0f (MD5) Previous issue date: 2012-05-02 / CNPq / The research was divided into chapters. The first assessed the post-embryonic development of Chrysomya albiceps (Widemann) on chicken gizzard (control: beef). There were four replications (100g each diet, 40 1st instar/2nd generation larvae) per treatment, each recipient was placed in a larger one containing sawdust and then sealed. The mature larvae were weighed and stored in test tubes. The variation among mature larva weight means and the duration of the larva, pupa and total stages were analyzed by the Student t test (?=5%), the viabilities by ANOVA and the sex ratio by the chi-square test. The following were recorded: mean temperature 25.6oC and 72.4% relative air humidity, larva-adult period mean duration of 8.1 days (meat) and 8.2 days (gizzard); 71% to 87% larva viability; 100% and 99% pupa viability 58% and 67% larva and adult viabilities, respectively. Chicken gizzard was shown to be satisfactory as diet for C. albiceps. The second chapter assessed the post embryonic development of Chysomya putoria (Widemann) in chicken gizzard and homogenized chicken gizzard in 65% agar (control: meat). Four replications (60 mL diet, 40 1st instar/5th generation larvae) were made per treatment. The homogenate was prepared in a mixer (gizzard, distilled water and agar). A mean temperature of 20.6 oC and 67.7% relative air humidity were recorded. The mean duration of the larva-adult period was 8.868 days (meat), 8.676 days (gizzard) and 9.067 days (homogenate); the larva viability was 98%; 92% and 73%; the pupa viability was 98%; 91% and 71%; the larva and adult viabilities were 93%; 83% and 64%, respectively. There were significant difference in the duration of the pupa period between meat and the homogenate. Both diets were shown to be satisfactory for C. putoria. The third chapter assessed different ciprofloxacin concentrations (3.33 ?g/mL; 6.66 ?g/mL and 13.33 ?g/mL in gizzard/65% agar homogenate) on C. putoria development (the control received distilled water). They were replicated four times (60 grams diet, 40 1st instar/3rd generation larvae) in an acclimatized chamber 30oC day/28 oC night, 70+10%relative air humidity and 14-hour photoperiod. There was no significant difference for: mean individual larva weight, mean duration of the larva inoculation until abandonment and the larva, pupa and total stages. Only treatment 2 differed significantly from the control in the larval and total viability. Ciprofloxacin seemed not to alter C. putoria development. The fourth chapter assessed different gentamicin concentrations (4.44?g/mL; 13.33?g/mL and 66.66?g/mL) on C. putoria. The materials and methods were similar to those of chapter III. There was no significant difference for: mean individual larva weight, mean duration of the larva inoculation until abandonment and the larva, pupa and total stages. Only treatment 2 differed significantly from the control for larva viability. Gentamicin seemed not to alter C. putoria development. The fifth chapter assessed different ampicillin concentrations (66?g/mL; 81.33?g/mL and 166.66?g/mL) on C. putoria. The materials and methods were similar to chapter III. There was no significant difference for: mean individual larva weight, mean duration of the larvae inoculation until abandonment and the larval, pupa and total stages. There was no significant difference for larva and total viability, but pupa viability in T1 differed significantly from the control and T2, and T3 differed from the control. Ampicillin seemed not to alter C. putoria development. / A pesquisa foi dividida em cap?tulos. O primeiro avaliou o desenvolvimento p?s-embrion?rio de Chrysomya albiceps (Widemann) em moela de frango (controle: carne bovina). Foram quatro repeti??es (100g de dieta cada, 40 larvas de 1? instar/2? gera??o) por tratamento, cada recipiente inserido em outro maior contendo serragem e vedado. As larvas maduras foram pesadas e armazenadas em tubos de ensaio. A varia??o entre m?dias de massa de larvas maduras e dura??es dos est?gios de larva, pupa e total foram analisadas por Teste t de Student (?=5%), as viabilidades por ANOVA, a raz?o sexual pelo qui-quadrado. Foram registradas temperatura m?dia 25,6?C e umidade relativa do ar m?dia 72,4%; dura??o m?dia do per?odo de larva a adulto 8,1 dias (carne) e 8,2 (moela); viabilidades de larva 71% e 87%; viabilidades de pupa 100% e 99%; viabilidades de larva a adulto 58% e 67%, respectivamente. Moela de frango se mostrou satisfat?ria como dieta para C. albiceps. O segundo cap?tulo avaliou desenvolvimento p?s-embrion?rio de Chysomya putoria (Widemann) em moela e homogenato de moela de frango em agar 65% (controle: carne). Foram quatro repeti??es (60 mL de dieta, 40 larvas de 1? instar/5?gera??o) por tratamento. O homogenato foi preparado em mixer (moela, ?gua destilada e agar). Foram registradas temperatura m?dia 20,6? C e umidade relativa do ar m?dia 67,7%. A dura??o m?dia do per?odo de larva a adulto foi 8,868 dias (carne), 8,676 (moela) e 9,067 (homogenato); as viabilidades larvais 98%; 92% e 73%; as viabilidades de pupa 98%; 91% e 71%; as viabilidades de larva a adulto 93%; 83% e 64%, respectivamente. Houve diferen?a significativa na dura??o do per?odo pupal entre carne e homogenato. Ambas dietas mostraram-se satisfat?rias para C. putoria. O terceiro cap?tulo avaliou diferentes concentra??es de ciprofloxacino (3,33 ?g/mL; 6,66 ?g/mL e 13,33 ?g/mL em homogenato de moela/agar 65%) sobre desenvolvimento de C. putoria (controle recebeu agua destilada). Foram replicados quatro vezes (60 gramas dieta, 40 larvas 1? ?nstar/3? gera??o) em c?mara climatizada 30?C dia/28?C noite, 70+10% U.R. e 14 horas fotoper?odo. N?o houve diferen?a significativa: massa individual m?dio das larvas, dura??o m?dia da inocula??o das larvas at? abandono e est?gios larval, pupal e total. Apenas tratamento 2 diferiu significativamente do controle nas viabilidades larval e total. Ciprofloxacino pareceu n?o alterar desenvolvimento de C. putoria. O quarto cap?tulo avaliou diferentes concentra??es de gentamicina (4,44?g/mL; 13,33?g/mL e 66,66?g/mL) sobre C. putoria. Os materiais e m?todos foram semelhantes ao do cap?tulo III. N?o houve diferen?a significativa: massa individual m?dia das larvas; dura??o m?dia da inocula??o das larvas at? abandono e dos est?gios larval, pupal e total. Apenas tratamento 2 diferiu significativamente do controle na viabilidade larval. Gentamicina pareceu n?o alterar o desenvolvimento de C. putoria. O quinto cap?tulo avaliou diferentes concentra??es de ampicilina (66?g/mL; 81,33?g/mL e 166,66?g/mL) sobre C. putoria. Os materiais e m?todos foram semelhantes ao cap?tulo III. N?o houve diferen?a significativa: massa individual m?dia das larvas, dura??o m?dia da inocula??o das larvas at? abandono e est?gios larval, pupal e total. N?o houve diferen?a significativa: viabilidades larval e total, por?m viabilidade pupal do T1 diferiu significativamente do controle e T2, e T3 diferiu do controle. Ampicilina pareceu n?o alterar desenvolvimento de C. putoria.
79

Estudo da ciprofloxacina através de cálculos ab-initio / Ab-Initio studies of ciprofloxacin

Camargo, Arthur Prado 26 May 2017 (has links)
A Ciprofloxacina é um antibiótico muito relevante, porém com efeitos colaterais indesejáveis, como convulsões, rompimento de tendão entre outros. Com o intuito de reduzir estes efeitos colaterais e para a liberação do fármaco em locais específicos, o uso de materiais lamelares, como cápsulas de armazenamento e transportador com alvo específico para biomoléculas ou células, tem sido sugerido pela literatura. A combinação de estudos teóricos e experimentais pode fornecer uma melhor compreensão da estrutura de agregados lamelares com o antibiótico Ciprofloxacina. Neste trabalho estudamos os diferentes estados iônicos da Ciprofloxacina (Cipro), obtendo os espectros de vibração (Infravermelho, Raman), Ressonância magnética nuclear de carbono e ótico (Ultravioleta-Visual). Estes resultados teóricos são comparados a resultados experimentais para investigar e caracterizar o estado molecular após intercalação. Utilizamos cálculos de estrutura eletrônica desenvolvidos no âmbito Teoria do Funcional da Densidade (DFT). Nossos resultados de análise dos espectros teóricos de Uv-Vis e de deslocamento químico obtido por RMN de Carbono revelaram que os espectros dos quatro estados iônicos da Cipro aqui estudados são muito semelhantes, o que não permite a diferenciação destes estados através destas técnicas. Por outro lado, nossos resultados de análise vibracional demonstraram frequências características de cada um dos estados iônicos. Este fato é importante, uma vez que permite identificar, através do espectro vibracional, cada um dos compostos presentes em uma dada amostra como, por exemplo, um agregado lamelar, utilizado para fins de liberação controlada de fármacos. / Ciprofloxacin is an important antibiotic, but with undesirable side effects. The use of layered materials as drug storage capsules and drug carriers can enable the development of target-specific drugs with high specificity for biomolecules or cells, which allow the release of drugs in chosen locations, thus reducing side effects .The combination of theoretical and experimental studies can provide a better understanding of the structure of lamellar aggregates with Ciprofloxacin antibiotic. In this context, to assist in the complete characterization of Ciprofloxacin, we perform theoretical calculations in the framework of the Density Functional Theory (DFT). We study different ionic states, obtaining the vibrational (IR, Raman), C-NMR and optical (UV/Vis) spectra. These theoretical results are compared with experimental results in order to unravel the molecular state upon encapsulation. Our results have shown that the Uv-Vis and NMR chemical shifts are not able to clearly differentiate the ionic states studied here. On the other hand, our calculation for the vibrational spectra reveals characteristic fingerprints of the Ciprofloxacin ionic states. This may permit, the identification of the ionic state of Ciprofloxacin in a certain sample, as layered materials, when used as drug carriers.
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Synthesis and Anti-MRSA Activity of Hydrophilic C3-Acylated N-Thiolated β-Lactams and N-Acyl Ciprofloxacin-N-Thiolated β-Lactam Hybrids

Bhattacharya, Biplob 01 January 2012 (has links)
The Turos laboratory has been working with N-thiolated β-lactams for years trying to understand the mode of action and structural features it needs to have biological activity. Over the years new data has shown promising inhibitory activity against various microbes. In this dissertation, a review of the vast amount of work carried out on N-thiolated β-lactams in Turos laboratory has been done and their novelty, in terms of structure and mechanism has been discussed. A complete outline of our work in the discovery and ongoing development of these compounds, starting from our initial, unexpected finding of antimicrobial activity for one of the lead compounds, to a more complete understanding of their chemical and biological mode of action and potential utility as antibacterial compounds, has been provided. Previous researches by graduate students in the Turos laboratory have shown that N-thiolated β-lactams targets Type II Fatty Acid Synthesis (FAS). In process of understanding this further, other FAS inhibiting antibiotics like Triclosan were compared to our lactams by adding excess of exogenous fatty acids. Results revealed vast differences in the MIC value of triclosan and N-thiolated β-lactams, giving an idea that there might be a different mode of action or a different target altogether. The third chapter discusses the study of attaching hydrophilic C3 side chains like amino acids and carbohydrates on N-thiolated β-lactams while studying the influence of microbiological activity. From the study it was found that the lengthening of the side chain halts the inhibitory activity regardless of whether the side chain contains unsaturation or branching. Results showed that polar groups were not well tolerated and the inhibitory activity goes down regardless of polarity. Finally, research on dual-action antibiotics was discussed. Antibiotics cause continuous bacterial resistance and in this aspect use of two drugs with different mode of action can call for reduction of the resistance. Herein, N-acyl ciprofloxacin and N-thiolated β-lactams were connected together via an ester linkage. Six new hybrid compounds have been synthesized successfully and tested against E. faecium, K. pneumoniae, A. baumannii, P. aeruginosa, and E. cloacae.

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