Pseudomonas aeruginosa é um dos principais agentes de infecção hospitalar que tem adquirido um caráter endêmico decorrente a sua resistência intrínseca e/ou adquirida aos antibacterianos comercialmente disponíveis. O objetivo do estudo foi avaliar, in vitro, opções terapêuticas baseadas na atividade sinérgica. Dez cepas de P. aeruginosa clonalmente não relacionadas, previamente caracterizadas como produtoras de metalo-beta-lactamase (M<font face=\"Symbol\">bL) do tipo SPM-1, VIM-1 e PA GIM-1, foram avaliadas. O efeito sinérgico foi investigado por Checkerboard e Time-Kill. As combinações [Piperacilina/Tazobactam x Aztreonam] e [Tigeciclina x nanofragmentos de bicamada de brometo de dioctadecildimetilamônio (DDA)] mostraram atividade sinérgica para 90 e 100% das cepas, respectivamente. Os resultados respaldam o uso terapêutico combinado de [Piperacilina/Tazobactam x Aztreonam], contra infecções produzidas por cepas de P. aeruginosa multirresistentes produtoras de M<font face=\"Symbol\">bLs, além disso, [DDA/Tigeciclina] pode constituir a base para consolidar uma nova forma farmacêutica de uso clínico. / Pseudomonas aeruginosa is a leading cause of nosocomial infections, which it has acquired an endemic status due to their intrinsic or acquired resistance to antibacterial agents commercially available. The aim of the study was to evaluate in vitro therapeutic options based on the synergistic activity. Ten clonally unrelated strains of P. aeruginosa, previously characterized as metallo-beta-lactamase (M<font face=\"Symbol\">bL) producers (i.e., SPM-1, VIM-1 and PA GIM-1) were evaluated. The synergistic effect was investigated by checkerboard and Time-Kill assays. The combinations [Piperacillin/Tazobactam x Aztreonam] and [Tigecycline x bilayer fragments of dioctadecyldimethylammonium bromide (DDA)] showed synergistic activity for 90 and 100% of the strains, respectively. The results support the use of combined therapy by using [Piperacillin/Tazobactam x Aztreonam] against infections produced by strains of P. aeruginosa producing M<font face=\"Symbol\">bLs, moreover, [DDA / Tigecycline] may be the basis for build a new pharmaceutical form for clinical use.

Made available in DSpace on 2015-05-14T13:00:15Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1737175 bytes, checksum: b24ecf4b4fe0ccef7cf186316f7a7469 (MD5) Previous issue date: 2010-11-16 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This study aimed to investigate the antifungal activity of essential oil (EO) of Cinnamomum zeylanicum Blume alone and combined with synthetic antifungal agents against Candida species. For this, it was determined the Minimum Inhibitory Concentration (MIC); Minimum Fungicidal Concentration (MFC); Fractional Inhibitory Concentration Index (FICI); microbial death curve promoted by the EO alone and combined with synthetic antifungals; action on fungal cell wall and interference of this combination on the fungal micromorphology. When assessed alone, C. zeylanicum and nystatin showed MIC of 312.5 &#956;g/mL and 64 &#956;g/mL, respectively. After combination, there was a reduction in MIC values for both substances, and were found values of respectively 39 &#956;g/mL and 32 &#956;g/mL for the EO and for Nystatin. It was verified a FICI value of 0.6024 (additivity). At all concentrations tested, these products alone and combined were able to reduce the number of CFU/mL, when compared with the control group from 30 min. It was also observed a reduction in the development of morphological structures of C. albicans cells, like pseudohyphae, blastoconidia and chlamydoconidia. When combined with miconazole, FICI values were 4.1248 (antagonism), 1.1248 (indifference) and 1.1248 (indifference), respectively, for C. albicans, C. tropicalis and C. krusei. Thus, it can be concluded that: C. zeylanicum showed activity against the Candida strains; this antifungal activity occurs, probably, by action of the essential oil in the process of fungal cell wall synthesis; the combination between C. zeylanicum EO and nystatin potentiated the inhibitory effect on growth of C. albicans strains, promoting a reduction in the development capacity of cellular morphologic structures. Nevertheless, the combination of C. zeylanicum EO and miconazole is not an advantageous possibility for growth inhibition of Candida spp. / Objetivou-se investigar a ação antifúngica do óleo essencial (OE) de Cinnamomum zeylanicum Blume isolado e associado a antifúngicos sintéticos sobre espécies de Candida. Para tanto, foi determinada a Concentração Inibitória Mínima (CIM), a Concentração Fungicida Mínima (CFM), índice de Concentração Inibitória Fracionada (ICIF), a Curva de Morte Microbiana promovida pelo OE isolado e associado a antifúngicos sintéticos, a ação sobre a parede celular fúngica e a interferência dessa associação sobre a micromorfologia fúngica. Quando avaliados isolados, C. zeylanicum e nistatina apresentaram CIM de, respectivamente, 312,5 &#956;g/mL e 64 &#956;g/mL. Após associação dos produtos avaliados, foi observada diminuição nos valores de CIM para ambas as substâncias, sendo encontrados valores de, respectivamente, 39 &#956;g/mL e 32 &#956;g/mL para o OE e nistatina, sendo verificado o valor do ICIF de 0,6024 (aditividade). Foi observado que em todas as concentrações avaliadas, os produtos isolados e associados foram capazes de reduzir significativamente o número de UFC/mL, quando comparados ao grupo controle a partir de 30 min. Também foi observada redução no desenvolvimento das estruturas morfológicas das células de C. albicans, como pseudo-hifas, bastoconídios e clamidoconídios. Quando associado ao miconazol, foi observado ICIF de, respectivamente, 4,1248 (antagonismo), 1,1248 (indiferença) e 1,1248 (indiferença), para C. albicans, C. tropicalis e C. krusei. Assim, verifica-se que C. zeylanicum exibiu ação sobre cepas de Candida, que essa atividade antifúngica apresentada pelo C. zeylanicum ocorre, provavelmente, por ação do óleo essencial no processo de síntese da parede celular fúngica, que associação do OE de C. zeylanicum e nistatina promoveu potencialização do efeito inibitório sobre o crescimento das cepas de C. albicans, promovendo redução na capacidade de desenvolvimento de estruturas morfológicas das células. Todavia, a associação do óleo essencial de C. zeylanicum ao miconazol não constitui em uma possibilidade vantajosa para inibição de crescimento de Candida spp.

A infecção de corrente sanguínea (ICS) causada por bactérias multirresistentes tem alta mortalidade em pacientes receptores de transplante de células-tronco hematopoiéticas (TCTH). A Pseudomonas aeruginosa é um dos agentes mais frequentes e de difícil tratamento nessa população de pacientes. Objetivos: Avaliar características clínicas, microbiológicas e moleculares de 30 isolados de P. aeruginosa resistente à carbapenêmicos (PARC) em ICS de pacientes submetidos a TCTH e a presença de sinergismo antimicrobiano in vitro. Métodos: Os dados clínicos foram obtidos retrospectivamente de prontuários médicos e registrados em banco de dados. Análises bivariadas e multivariadas foram realizadas para avaliar determinantes de desfechos clínicos e uma curva de sobrevida foi construída. Determinou-se a concentração inibitória mínima (CIM) dos antimicrobianos por meio de microdiluição, foram realizados ensaios de sinergismo por método de checkerboard e time-kill, avaliação da clonalidade por eletroforese em campo pulsado e detecção de genes codificadores de mecanismos de resistência e virulência por reação em cadeia de polimerase. O sequenciamento do genoma completo (WGS) dos principais clones foi realizado por Nextera XT, utilizando a tecnologia Illumina MiSeq. Resultados: A maioria dos pacientes era do gênero feminino, com mediana de idade de 48 anos. Neutropenia foi presente em 93% dos pacientes e colonização prévia por PARC em 32%. A mortalidade em 14 dias foi 68%; a maioria dos pacientes que morreram foram transplantados alogênicos (79% vs. 17% entre receptores de transplante autólogo; p=0,012). Pacientes tratados com duas ou três drogas não apresentaram diferença estatisticamente significante na mortalidade até 14 dias após a ICS. Foram avaliados 30 isolados bacterianos. Todos apresentaram alto nível de resistência ao meropenem (MERO): CIM90 > 512 ug/mL; dois terços eram resistentes à amicacina (AMK) (CIM 2-512 ug/mL) e todos mantinham sensibilidade à colistina (COL). Muitos isolados (17/30) alcançaram efeito sinérgico in vitro pelo método time-kill com a combinação MERO mais COL, mas não com AMK. Nenhum antagonismo foi observado. Houve menor mortalidade em pacientes cujo isolado apresentou sinergismo entre COL e MERO quando comparados a pacientes portadores de isolados sem sinergismo, sem significância estatística. O gene de carbapenamase mais identificado foi blaSPM e 6 isolados apresentaram blaSPM e blaKPC. Os isolados apresentaram genes relacionados com virulência, tais como toxA, exoS e lasB; pacientes com ICS causada por P. aeruginosa que abrigava o gene lasB apresentaram maior risco de evoluir para o óbito. O WGS mostrou que os clones abrigavam SPM-1, Tn4371, mutações em porinas, em partes das bombas de efluxo, nas proteínas ligadores de penicilina (PBP) e pertenciam a ST277. Conclusão: As ICS por PARC cursaram com alta mortalidade em pacientes submetidos à TCTH. Houve uma grande proporção de resultados positivos para sinergismo entre os antimicrobianos in vitro, mas não foi possível demonstrar benefício estatisticamente significante no uso da terapia combinada com três drogas. Os clones carreavam SPM-1, Tn4371 e pertenciam a ST277 / Bloodstream infection (BSI) has high mortality in hematopoietic stem cell transplant (HSCT) recipients and Pseudomonas aeruginosa is an important and challenging organism. Objectives: To evaluate clinical, microbiological and molecular features of carbapenem-resistant P. aeruginosa (CRPA) isolates from BSI identified among HSCT patients and address in vitro synergy of antibiotic combination. Methods: Patient medical records were retrospectively reviewed and registered in a database. We used bivariate and multivariate analyzes to investigate determinants of clinical outcomes, and demonstrated overall mortality using a survival curve. We determined minimal inhibitory concentrations (MIC) for antimicrobials and in vitro synergies using checkerboard and time-kill assays, pulsed-field electrophoresis (PFGE) for clonality assessment and polymerase chain reaction (PCR) to detect carbapenamases and virulence genes were performed for all isolates. Whole genome sequence (WGS) of main clones was performed by Nextera XT, using Illumina MiSeq technology. Results: Most patients were female, median age was 48 years old. Main baseline disease was acute leukemia and 68% received allogeneic HSCT. 93% of patients had neutropenia and 32% had prior CRPA gut colonization.14-day mortality was 68%; mortality was higher among allogeneic HSCT recipients compared to autologous HSCT recipients (79% vs. 17% p = 0,012). Patients treated with two or three drugs did not present a statistically significant difference in 14-day mortality after BSI. In total, 30 bacterial isolates were analyzed; all presented a high resistance level to meropenem (MERO): MIC90 > 512ug/mL; two thirds were also resistant to amikacin (AMK) (MIC 2-512 ug/mL) and all were susceptible to colistin (COL). Many (17/30) isolates achieved in vitro synergistic effect in time-kill assay with the association of MERO and COL, but synergistic effect was not observed with AMK, by time-kill. No antagonistic effect was observed. There was a tendency towards better survival in patients whose CRPA isolate had in vitro synergy between COL and MERO without statistical significance. The most frequent carbapenamase gene identified was blaSPM, and six co-harboured both blaKPC and blaSPM. Isolates presented genes related to virulence factors such as toxA, exoS and more patients with BSI caused by P. aeruginosa harbouring gene lasB evolved to death. WGS analysis showed that clones harboured SPM-1, Tn4371 and belonged to ST277. They also presented mutations in genes related with porins and efflux pumps, as well in penicillin binding proteins (PBPs). Conclusion: CRPA BSI as associated with high mortality in HSCT recipients. A large proportion of isolates had in vitro synergy; however, we could not demonstrate statistically significant benefit in the use of combination therapy. Clones carried SPM-1, Tn4371 and belonged to ST277

Introdução: Várias são as propostas descritas para tratar farmacologicamente a lesão traumática da medula espinal. A metilprednisolona já foi padronizada para uso clínico. O fator estimulador de colônia de granulócitos (G-CSF) tem sido promissor em estudos experimentais e clínicos. Não há pesquisas quanto ao efeito da associação dos dois fármacos. Objetivo: Avaliar o efeito do tratamento com o fator estimulador de colônia de granulócitos associado a metilprednisolona na lesão medular aguda experimental em ratos. Material e métodos: Foram avaliados 40 ratos Wistar submetidos a lesão medular moderada com o NYU-Impactor. Os animais foram divididos em quatro grupos de 10 ratos. O Grupo Controle não recebeu tratamento; o Grupo G-CSF, foi tratado com G-CSF no momento da lesão e diariamente ao longo dos cinco dias subsequentes; o Grupo Metilprednisolona, com metilprednisolona durante 24 horas; e o Grupo G-CSF/Metilprednisolona, com metilprednisolona durante 24 horas e G-CSF no momento da lesão e ao longo de cinco dias. Os animais foram mantidos vivos durante 42 dias; a avaliação funcional foi realizada com a aplicação da escala funcional de Basso, Beattie e Bresnahan (BBB) nos dias 2, 7, 14, 21, 28, 35 e 42 subsequentes à lesão. A avaliação dos potenciais evocados motores foi realizada no dia 42 e a avaliação histológica da lesão da região da medula espinal lesada, realizada logo após a eutanásia ocorrida no dia 42. Resultados e conclusões: A associação de metilprednisolona e G-CSF no tratamento do traumatismo medular contuso experimental em ratos promoveu melhora neurológica avaliada pela escala BBB superior à melhora promovida pela metilprednisolona e G-CSF quando utilizadas isoladamente. A associação teve também efeito sinérgico que resultou em melhora nos parâmetros histológicos no local da lesão. Não houve diferença entre os grupos quanto à avaliação neurofisiológica / Introduction: There are several proposals to pharmacologically treat traumatic spinal cord injury. Methylprednisolone has already been standardized for clinical use. Granulocyte colony stimulating factor (G-CSF) has been promising in experimental and clinical studies. There is no research on the effect of the association of the two drugs. Objective: to evaluate the effect of combined treatment of the granulocyte colony-stimulating factor (G-CSF) associated with methylprednisolone in experimental acute spinal cord injury in rats. Material and methods: Forty male Wistar rats were submitted to a moderate spinal cord injury with the NYU-Impactor. The animals were divided into four groups of ten rats each. The Control Group was not treated; the G-CSF Group was treated with G-CSF at the time of injury and daily over the next five days; the Methylprednisolone Group was treated with methylprednisolone for 24 hours; the G-CSF/methylprednisolone Group, was treated with methylprednisolone for 24 hours and G-CSF at the time of injury and daily over the next five days. The animals were kept alive for 42 days; Functional evaluation was performed using the Basso, Beattie and Bresnahan (BBB) score on days 2, 7, 14, 21, 28, 35 and 42 following the spinal cord injury. Evaluation of motor evoked potentials was held and histological examination of the lesion of the spinal cord was done immediately after euthanasia on day 42. Results and conclusions: The combination of methylprednisolone and G-CSF in the treatment of experimental spinal cord injury in rats promoted neurological improvement as assessed by BBB scale with greater improvement than with methylprednisolone or G-CSF when used alone. The combination of treatment had also a synergistic effect resulting in improvement in histological parameters at the injury site. There was no difference between groups regarding neurophysiological evaluation

Nos últimos anos a incidência de infecções causadas por bactérias Gram-negativas multirresistentes aumentou expressivamente. Esse fenômeno não foi acompanhado pelo desenvolvimento de novos antimicrobianos, resultando em infecções cuja opção de tratamento é a combinação de antimicrobianos. Acinetobacter baumannii, Pseudomonas aeruginosa e Serratia marcescens são importantes agentes de infecções relacionadas à assistência à saúde (IRAS), e capazes de adquirir resistência a várias classes de antimicrobianos, como os carbapenêmicos e polimixinas. Os testes que avaliam sinergismo in vitropodem ser uma ferramenta importante na escolha do tratamento antibiótico adequado para infecções causadas por microrganismos multirresistentes. O objetivo deste estudo foi avaliar métodos de sinergismo in vitroque possam ser utilizados na rotina de laboratórios de microbiologia clínica como alternativa ao método considerado padrão ouro (time-kill). Foram selecionados para o estudo 48 isolados Gram-negativos não fermentadores (20 A. baumannii e 28 P. aeruginosa) e 14 fermentadores (S. marcescens) do banco de cepas do LIM-54 com diferentes mecanismos de resistência identificados por PCR e sequenciamento total do genoma. Foram realizados, concentração inibitória mínima dos antimicrobianos e avaliação do sinergismo pelos métodos time-kill (TK), disco aproximação (DA) e CIM:CIM razão.A concordância dos métodos foi avaliada por teste de kappa e os resultados discordantes foram classificados em tipos de erros baseado no FDA.Os isolados apresentaram alta proporção de resistência a meropenem e 7 isolados de A. baumanniiapresentaram resistência a colistina. A combinação de colistina com fosfomicina ou meropenem apresentou elevado efeito sinérgico para os isolados de A. baumanniiresistentes a colistina pelo DA e TK. Por outro lado, a combinação de fosfomicina-meropenem apresentou concordância boa pelo teste de kappa e baixo número de erros entre os métodos TK e DA para todos os isolados de A. baumannii. Para os isolados de P. aeruginosa não foram detectados efeitos sinérgicos pelos métodos DA e CIM:CIM razão.O método CIM:CIM razão apresentou alta concordância com o TK entre os isolados de A. baumannii resistentes a colistina. A combinação ceftazidima-avibactam com meropenem apresentou elevado efeito sinérgico para os isolados de S. marcescensportadores do gene blaKPC-2 pelo DA e TK. O método de DA apresentou uma boa correlação com o TK para a combinação de fosfomicina-meropenem e ceftazidima-avibactam-meropenem, com baixa porcentagem de erros menores, podendo ser utilizado para avaliar sinergismo in vitro para essas combinações. Não foi identificado no estudo efeito antagônico, portanto, foram encontrados somente erros menores / In recent years, the incidence of infections caused by multiresistant Gram-negative bacteria has increased. This event has not been accompanied by the development of new antimicrobials, resulting in infections which treatment option is the combination of antimicrobials. Acinetobacter baumannii, Pseudomonas aeruginosa and Serratia marcescens are important causesof Hospital Acquired Infection (HAI), and able to acquire resistance to multiple classes of antimicrobials, such ascarbapenems and polymyxins. Synergism testing may be an important tool in choose the appropriate antibiotic treatment. The aim of this study was to evaluate in vitro synergism methods that can be used in a clinical microbiology laboratory as an alternative to the method considered the gold standard (time-kill).For the study were selected 48 non-fermenting (20 A. baumannii and 28 P. aeruginosa)and 14 fermenting(S. marcescens) Gram-negativeisolates from LIM-54strains bench with different resistance mechanisms identified by PCR and total genome sequencing.Minimum antimicrobial inhibitory concentration and synergism evaluation by time-kill (TK), disk approximation (DA) and MIC: MIC ratio were performed. Agreement of the methods was evaluated by kappa test and the discordant results were classified in types of errors based on the FDA. The isolates showed high proportion of resistant to meropenem and 7A. baumannii isolates showed resistance to colistin. The combination of colistin with fosfomycin or meropenem showed high synergistic effect for colistin-resistant A. baumannii isolates by DA and TK.On the other hand, the combination of fosfomycin-meropenem showed good concordance by kappa test and low number of errors between TK and DA for all A. baumannii isolates.For P. aeruginosa isolates no synergistic effects were detected by DA and MIC: MIC ratio.The method MIC: MIC ratio showed high concordance with the TK among the colistin-resistant A. baumannii isolates.The combination ceftazidime-avibactam with meropenem showed high synergistic effect for the isolates of S. marcescenscarryingblaKPC-2 gene by DA and TK. The DA showed a good agreement with TK for the combination of fosfomycin-meropenem and ceftazidime-avibactam-meropenem, with a low percentage of minor errors, and could be used to evaluate synergism in vitro for these combinations

Introdução: Várias são as propostas descritas para tratar farmacologicamente a lesão traumática da medula espinal. A metilprednisolona já foi padronizada para uso clínico. O fator estimulador de colônia de granulócitos (G-CSF) tem sido promissor em estudos experimentais e clínicos. Não há pesquisas quanto ao efeito da associação dos dois fármacos. Objetivo: Avaliar o efeito do tratamento com o fator estimulador de colônia de granulócitos associado a metilprednisolona na lesão medular aguda experimental em ratos. Material e métodos: Foram avaliados 40 ratos Wistar submetidos a lesão medular moderada com o NYU-Impactor. Os animais foram divididos em quatro grupos de 10 ratos. O Grupo Controle não recebeu tratamento; o Grupo G-CSF, foi tratado com G-CSF no momento da lesão e diariamente ao longo dos cinco dias subsequentes; o Grupo Metilprednisolona, com metilprednisolona durante 24 horas; e o Grupo G-CSF/Metilprednisolona, com metilprednisolona durante 24 horas e G-CSF no momento da lesão e ao longo de cinco dias. Os animais foram mantidos vivos durante 42 dias; a avaliação funcional foi realizada com a aplicação da escala funcional de Basso, Beattie e Bresnahan (BBB) nos dias 2, 7, 14, 21, 28, 35 e 42 subsequentes à lesão. A avaliação dos potenciais evocados motores foi realizada no dia 42 e a avaliação histológica da lesão da região da medula espinal lesada, realizada logo após a eutanásia ocorrida no dia 42. Resultados e conclusões: A associação de metilprednisolona e G-CSF no tratamento do traumatismo medular contuso experimental em ratos promoveu melhora neurológica avaliada pela escala BBB superior à melhora promovida pela metilprednisolona e G-CSF quando utilizadas isoladamente. A associação teve também efeito sinérgico que resultou em melhora nos parâmetros histológicos no local da lesão. Não houve diferença entre os grupos quanto à avaliação neurofisiológica / Introduction: There are several proposals to pharmacologically treat traumatic spinal cord injury. Methylprednisolone has already been standardized for clinical use. Granulocyte colony stimulating factor (G-CSF) has been promising in experimental and clinical studies. There is no research on the effect of the association of the two drugs. Objective: to evaluate the effect of combined treatment of the granulocyte colony-stimulating factor (G-CSF) associated with methylprednisolone in experimental acute spinal cord injury in rats. Material and methods: Forty male Wistar rats were submitted to a moderate spinal cord injury with the NYU-Impactor. The animals were divided into four groups of ten rats each. The Control Group was not treated; the G-CSF Group was treated with G-CSF at the time of injury and daily over the next five days; the Methylprednisolone Group was treated with methylprednisolone for 24 hours; the G-CSF/methylprednisolone Group, was treated with methylprednisolone for 24 hours and G-CSF at the time of injury and daily over the next five days. The animals were kept alive for 42 days; Functional evaluation was performed using the Basso, Beattie and Bresnahan (BBB) score on days 2, 7, 14, 21, 28, 35 and 42 following the spinal cord injury. Evaluation of motor evoked potentials was held and histological examination of the lesion of the spinal cord was done immediately after euthanasia on day 42. Results and conclusions: The combination of methylprednisolone and G-CSF in the treatment of experimental spinal cord injury in rats promoted neurological improvement as assessed by BBB scale with greater improvement than with methylprednisolone or G-CSF when used alone. The combination of treatment had also a synergistic effect resulting in improvement in histological parameters at the injury site. There was no difference between groups regarding neurophysiological evaluation

AQ4N (banoxantrone) is a prodrug that, under hypoxic conditions, is enzymatically converted to a cytotoxic DNA-binding agent, AQ4. Incorporation of AQ4N into conventional chemoradiation protocols therefore targets both oxygenated and hypoxic regions of tumors, and potentially will increase the effectiveness of therapy. This current pharmacodynamic and efficacy study was designed to quantify tumor exposure to AQ4 following treatment with AQ4N, and to relate exposure to outcome of treatment. A single dose of 60 mg/kg AQ4N enhanced the response of RT112 (bladder) and Calu-6 (lung) xenografts to treatment with cisplatin and radiation therapy. AQ4N was also given to separate cohorts of tumor-bearing mice 24 hours before tumor excision for subsequent analysis of metabolite levels. AQ4 was detected by high performance liquid chromatography/mass spectrometry in all treated samples of RT112 and Calu-6 tumors at mean concentrations of 0.23 and 1.07 microg/g, respectively. These concentrations are comparable with those shown to be cytotoxic in vitro. AQ4-related nuclear fluorescence was observed in all treated tumors by confocal microscopy, which correlated with the high performance liquid chromatography/mass spectrometry data. The presence of the hypoxic marker Glut-1 was shown by immunohistochemistry in both Calu-6 tumors and RT112 tumors, and colocalization of AQ4 fluorescence and Glut-1 staining strongly suggested that AQ4N was activated in these putatively hypoxic areas. This is the first demonstration that AQ4N will increase the efficacy of chemoradiotherapy in preclinical models; the intratumoral levels of AQ4 found in this study are comparable with tumor AQ4 levels found in a recent phase I clinical study, which suggests that these levels could be potentially therapeutic.

Ng, Po Yan. / Thesis submitted in: November 2006. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 109-120). / Abstracts in English and Chinese. / Acknowledgement --- p.i / Abstract --- p.ii / 摘要 --- p.iii / Table of Contents --- p.iv / List of Figures --- p.viii / List of Tables --- p.xi / List of Abbreviation --- p.xii / Chapter Chapter 1 --- Introduction / Chapter 1.1 --- A General Introduction to the Development and Clinical Activities of Platinum Drugs --- p.1 / Chapter 1.1.1 --- Platinum Drugs used in a Clinical Setting --- p.4 / Chapter 1.1.2 --- Platinum Drugs under Clinical Trials --- p.5 / Chapter 1.1.3 --- Platinum Compounds with Dual Mechanisms --- p.7 / Chapter 1.2 --- Platinum Drug Antitumor Mechanism --- p.9 / Chapter 1.3 --- Limitations of Platinum Drugs --- p.12 / Chapter 1.3.1 --- Toxicity --- p.12 / Chapter 1.3.2 --- Drug Resistance or Cross Resistance --- p.15 / Chapter 1.3.2.1 --- Reduced Drug Accumulation or Increased Drug Efflux --- p.16 / Chapter 1.3.2.2 --- Drug Inactivation --- p.18 / Chapter 1.3.2.3 --- Enhanced DNA Repair --- p.19 / Chapter 1.4 --- Why Combinational Therapy? --- p.21 / Chapter 1.4.1 --- Antimetabolites --- p.20 / Chapter 1.4.2 --- Topoisomerase Inhibitors --- p.22 / Chapter 1.4.3 --- Tubulin-Active Antimitotic Agents --- p.24 / Chapter 1.4.4 --- Demethylcantharidin as a potential candidate for drug combination --- p.28 / Chapter 1.5 --- Study Objectives --- p.31 / Chapter Chapter 2 --- Materials and Methods / Chapter 2.1 --- Cell Lines --- p.33 / Chapter 2.2 --- Cancer Cell Preparation / Chapter 2.2.1 --- Chemicals and Reagents --- p.33 / Chapter 2.2.2 --- Cell Culture Practice --- p.34 / Chapter 2.2.2.1 --- Subcultures --- p.35 / Chapter 2.2.2.2 --- Cryopreservation --- p.37 / Chapter 2.2.2.3 --- Thawing Cryopreservated Cells --- p.38 / Chapter 2.2.3 --- Development of Drug-Resistant Cell Lines --- p.39 / Chapter 2.3 --- Growth Inhibition Assay / Chapter 2.3.1 --- Evaluation of Cytotoxicity in vitro --- p.40 / Chapter 2.3.2 --- Drug Pretreatment --- p.43 / Chapter 2.3.3 --- Drug Pre-sensitization with Concurrent Treatment --- p.44 / Chapter 2.4 --- Calculations for Drug Combinations --- p.46 / Chapter 2.5 --- Statistical Analysis --- p.49 / Chapter Chapter 3 --- Results and Discussions / Chapter 3.1 --- In vitro Cytotoxicity and Evaluation of Drug Resistance --- p.50 / Chapter 3.2 --- Role of Leaving Ligand in a Platinum Complex --- p.58 / Chapter 3.3 --- Priority in Selecting the Most Effective Drug Combination --- p.66 / Chapter 3.4 --- Drug Combination Studies / Chapter 3.4.1 --- Drug Combination Prescreening --- p.68 / Chapter 3.4.1.1 --- Comparison of the effectiveness of the three Drug Combinations --- p.72 / Chapter 3.4.1.2 --- Rationale for Drug Combination Studies presented in Section 3.4.2 & 3.4.3 --- p.73 / Chapter 3.4.2 --- Drug Pre-sensitization Studies in Colorectal Cancer Cell Lines --- p.74 / Chapter 3.4.2.1 --- Comparison of Drug Pre-sensitization Treatment in Sensitive Colorectal Cancer Cell Lines --- p.84 / Chapter 3.4.2.2 --- Comparison of Drug Pre-sensitization Treatment in Sensitive and Oxaliplatin Resistant HCT116 Colorectal Cancer Cell Lines --- p.87 / Chapter 3.4.3 --- Drug Pre-sensitization Studies in Liver Cancer Cell Lines --- p.89 / Chapter 3.4.3.1 --- Comparison of Drug Pre-sensitization Treatment in Sensitive Liver Cancer Cell Lines --- p.99 / Chapter 3.4.3.2 --- Comparison of Drug Pre-sensitization Treatment in Sensitive and Cisplatin Resistant SK-Hepl Liver Cancer Cell Line --- p.101 / Chapter 3.5 --- Possible Explanation to the Observed Drug Combination Effect --- p.103 / Chapter 3.6 --- General Protocols for Drug Combinations --- p.105 / Chapter Chapter 4 --- Conclusions / Reference --- p.109 / Appendices --- p.121 / Chapter I a. --- "Raw Data of Pre-screening for HCT116 (Cisplatin, [Pt(DMC)(NH3)2] and Pt(DMC)(NH2CH3)2])" --- p.122 / Chapter I b. --- "Raw Data of Pre-screening for HCT116 ([Pt(DMC)(R,R-DACH)] and Oxaliplatin)" --- p.123 / Chapter II a. --- "Raw Data of Pre-screening for SK-Hepl (Cisplatin, [Pt(DMC)(NH3)2] and Pt(DMC)(NH2CH3)2])" --- p.124 / Chapter II b. --- "Raw Data of Pre-screening for SK-Hepl ([Pt(DMC)(R,R-DACH)] and Oxaliplatin)" --- p.125 / Chapter III a. i) --- "Isobolograms for HCT116 (Cisplatin, [Pt(DMC)(NH3)2] and Pt(DMC)(NH2CH3)2])" --- p.126 / Chapter III a. ii) --- "Raw Data for HCT116 (Cisplatin, [Pt(DMC)(NH3)2] and Pt(DMC)(NH2CH3)2])" --- p.127 / Chapter III b. i) --- "Isobolograms for HCT116 ([Pt(DMC)(R,R-DACH)] and Oxaliplatin)" --- p.128 / Chapter III b. ii) --- "Raw Data for HCT116 ([Pt(DMC)(R,R-DACH)] and Oxaliplatin)" --- p.129 / Chapter IV a. i) --- "Isobolograms for HCT1160xaR (Cisplatin, [Pt(DMC)(NH3)2] and Pt(DMC)(NH2CH3)2])" --- p.130 / Chapter IV a. ii) --- "Raw Data for HCT1160xaR (Cisplatin, [Pt(DMC)(NH3)2] and Pt(DMC)(NH2CH3)2])" --- p.131 / Chapter IV b. i) --- "Isobolograms for HCT1160xaR ([Pt(DMC)(R,R-DACH)] and Oxaliplatin)" --- p.132 / Chapter IV b. ii) --- "Raw Data for HCT1160xaR ([Pt(DMC)(R,R-DACH)] and Oxaliplatin)" --- p.133 / Chapter V a. i) --- "Isobolograms for HT29 (Cisplatin, [Pt(DMC)(NH3)2] and Pt(DMC)(NH2CH3)2])" --- p.134 / Chapter V a. ii) --- "Raw Data for HT29 (Cisplatin, [Pt(DMC)(NH3)2] and Pt(DMC)(NH2CH3)2])" --- p.135 / Chapter V b. i) --- "Isobolograms for HT29 ([Pt(DMC)(R,R-DACH)] and Oxaliplatin)" --- p.136 / Chapter V b. ii) --- "Raw Data for HT29 ([Pt(DMC)(R,R-DACH)] and Oxaliplatin)" --- p.137 / Chapter VI a. i) --- Isobolograms for Hep G2 (Cisplatin and [Pt(DMC)(NH3)2]) --- p.138 / Chapter VI a. ii) --- Raw Data for Hep G2 (Cisplatin and [Pt(DMC)(NH3)2]) --- p.139 / Chapter VI b. i) --- "Isobolograms for Hep G2 ([Pt(DMC)(R,R-DACH)] and Oxaliplatin)" --- p.140 / Chapter VI b. ii) --- "Raw Data for Hep G2 ([Pt(DMC)(R,R-DACH)] and Oxaliplatin)" --- p.141 / Chapter VII a. i) --- "isobolograms for SK Hep 1 (Cisplatin, [Pt(DMC)(NH3)2] and Pt(DMC)(NH2CH3)2])" --- p.142 / Chapter VII a. ii) --- "Raw Data for SK Hep 1 (Cisplatin, [Pt(DMC)(NH3)2] and Pt(DMC)(NH2CH3)2])" --- p.143 / Chapter VII b.i) --- "Isobolograms for SK Hep 1 ([Pt(DMC)(R,R-DACH)] and Oxaliplatin)" --- p.144 / Chapter VII b. ii) --- "Raw Data for SK Hep 1 ([Pt(DMC)(R,R-DACH)] and Oxaliplatin)" --- p.145 / Chapter VIII a. i) --- "Isobolograms for SK Hep ICisR (Cisplatin, [Pt(DMC)(NH3)2] and Pt(DMC)(NH2CH3)2])" --- p.146 / Chapter VIII a. ii) --- "Raw Data for SK Hep ICisR (Cisplatin, [Pt(DMC)(NH3)2] and Pt(DMC)(NH2CH3)2])" --- p.147 / Chapter VIII b. i) --- "Isobolograms for SK Hep ICisR ([Pt(DMC)(R,R-DACH)] and Oxaliplatin)" --- p.148 / Chapter VIII b. ii) --- "Raw Data for SK Hep ICisR ([Pt(DMC)(R,R-DACH)] and Oxaliplatin)" --- p.149

OBJECTIVE: Development of treatment resistance and adverse toxicity associated with classical chemotherapeutic agents highlights the need for safer and effective therapeutic approaches. Herein, we examined the effectiveness of a combination treatment regimen of 5-fluorouracil (5-FU) and curcumin in colorectal cancer (CRC) cells. METHODS: Wild type HCT116 cells and HCT116+ch3 cells (complemented with chromosome 3) were treated with curcumin and 5-FU in a time- and dose-dependent manner and evaluated by cell proliferation assays, DAPI staining, transmission electron microscopy, cell cycle analysis and immunoblotting for key signaling proteins. RESULTS: The individual IC50 of curcumin and 5-FU were approximately 20 microM and 5 microM in HCT116 cells and 5 microM and 1 microM in HCT116+ch3 cells, respectively (p<0.05). Pretreatment with curcumin significantly reduced survival in both cells; HCT116+ch3 cells were considerably more sensitive to treatment with curcumin and/or 5-FU than wild-type HCT116 cells. The IC50 values for combination treatment were approximately 5 microM and 1 microM in HCT116 and 5 microM and 0.1 microM in HCT116+ch3, respectively (p<0.05). Curcumin induced apoptosis in both cells by inducing mitochondrial degeneration and cytochrome c release. Cell cycle analysis revealed that the anti-proliferative effect of curcumin and/or 5-FU was preceded by accumulation of CRC cells in the S cell cycle phase and induction of apoptosis. Curcumin potentiated 5-FU-induced expression or cleavage of pro-apoptotic proteins (caspase-8, -9, -3, PARP and Bax), and down-regulated anti-apoptotic (Bcl-xL) and proliferative (cyclin D1) proteins. Although 5-FU activated NF-kappaB/PI-3K/Src pathway in CRC cells, this was down-regulated by curcumin treatment through inhibition of IkappaBalpha kinase activation and IkappaBalpha phosphorylation. CONCLUSIONS: Combining curcumin with conventional chemotherapeutic agents such as 5-FU could provide more effective treatment strategies against chemoresistant colon cancer cells. The mechanisms involved may be mediated via NF-kappaB/PI-3K/Src pathways and NF-kappaB regulated gene products.

Mast cells play pivotal roles in immunoglobulin (Ig) E-mediated airway inflammation, expressing interleukin (IL)-13 and monocyte chemoattractant protein-1 (MCP-1), which in turn regulate IgE synthesis and/or inflammatory cell recruitment. The molecular effects of IL-1beta on cytokine expression by human mast cells (HMC) have not been studied well. In this report, we provide evidence that human umbilical cord blood-derived mast cells (CBDMC) and HMC-1 cells express the type 1 receptor for IL-1. We also demonstrate that IL-1beta and tumor necrosis factor-alpha are able to induce, individually or additively, dose-dependent expression of IL-13 and MCP-1 in these cells. The induction of IL-13 and MCP-1 gene expression by IL-1beta was accompanied by the activation of IL-1 receptor-associated kinase and translocation of the transcription factor, nuclear factor (NF) kappaB into the nucleus. Accordingly, Bay-11 7082, an inhibitor of NF-kappaB activation, inhibited IL-1beta-induced IL-13 and MCP-1 expression. IL-1beta also induced IL-13 promoter activity while enhancing the stability of IL-13 messenger RNA transcripts. Dexamethasone, a glucocorticoid, inhibited IL-1beta-induced nuclear translocation of NF-kappaB and also the secretion of IL-13 from mast cells. Our data suggest that IL-1beta can serve as a pivotal costimulus of inflammatory cytokine synthesis in human mast cells, and this may be partly mediated by IL-1 receptor-binding and subsequent signaling via nuclear translocation of NF-kappaB. Because IL-1beta is a ubiquitously expressed cytokine, these findings have important implications for non-IgE-mediated signaling in airway mast cells as well as for innate immunity and airway inflammatory responses, such as observed in extrinsic and intrinsic asthma.