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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.
91

Avaliação da interferência do diabetes na biodistribuição e na atividade antitumoral da cisplatina em camundongos / Evaluation of the interference of diabetes in the biodistribution and antitumor activity

Márcia Cristina da Silva Faria 23 September 2011 (has links)
A cisplatina (Cis-diamino-dicloro-platina II) é um dos mais efetivos quimioterápicos, porém seu uso clínico é altamente limitado devido à sua nefrotoxicidade. Estudos sugerem que o diabetes atua como fator protetor contra a nefrotoxicidade da cisplatina, entretanto, os mecanismos envolvidos ainda não foram elucidados. Esta nefroproteção tem sido associada ao menor acúmulo de cisplatina nos rins, o que poderia ser atribuído a problemas no transporte ativo das células do túbulo proximal ou ainda a alterações farmacocinéticas provocadas pelo diabetes. Entretanto, não se sabe ainda se os mecanismos envolvidos na nefroproteção do diabetes interferem na atividade antitumoral da cisplatina. No presente estudo foram avaliados os efeitos do diabetes na nefrotoxicidade e na atividade antitumoral da cisplatina em camundongos portadores de sarcoma 180, divididos em 4 grupos (n=8): (i) C, grupo controle (sem tratamento); (ii) CIS, grupo tratado com cisplatina; (iii) DB, grupo diabético (estreptozotocina) e (iv) DB+CIS grupo diabético tratado com cisplatina. Os parâmetros avaliados foram: marcadores de função renal e de estresse oxidativo, histopatologia do tecido renal, desenvolvimento do tumor, sobrevida dos animais, genotoxicidade da cisplatina, concentração de platina nos órgãos e no tumor e marcadores de apoptose. Os resultados indicam que: (i) o diabetes protege contra o dano renal induzido pela cisplatina (ii) o diabetes altera a biodistribuição da cisplatina no tumor, nos rins e em vários órgãos; (iii) o diabetes diminui a atividade antitumoral da cisplatina. Os dados obtidos são relevantes, dada a prevalência de certos tipos de tumores em pacientes diabéticos e a importância da cisplatina na quimioterapia e, portanto, podem indicar a necessidade de uma maior atenção no tratamento anticâncer de pacientes diabéticos. / Cisplatin (cis-diamine-dichloro-platinum ll) is one of the most effective chemotherapeutic drugs; however, its clinical use is highly restricted due to its nephrotoxicity. Studies suggest that diabetes is a protective factor against cisplatin nephrotoxicity, but the mechanisms involved remain unclear. This nephroprotection has been associated with decreased cisplatin accumulation in the kidneys, which could be attributed to impaired active transport in proximal tubular cells or even to pharmacokinetic changes induced by diabetes. However, it is not clear if the mechanisms involved in the renal protection of diabetes interfere in the antitumor activity of cisplatin. In the present study we evaluated the effects of diabetes on the nephrotoxicity and antitumor activity of cisplatin in tumor-bearing mice, divided in four groups (n=8): (i) C, control group (without treatment); (ii) CIS, cisplatin group; (iii) DB, diabetic group (streptozotocin) and (iv) DB+CIS, diabetic group treated with cisplatin. The following parameters were evaluated: markers of renal function and oxidative stress, renal histopathology, tumor development, animals survival, cisplatin genotoxicity, platinum concentration in organs and tumor and markers of apoptosis. Our results indicate that: (i) diabetes protects against the renal damage induced by cisplatin (ii) diabetes alters the biodistribution of cisplatin in tumor, kidneys and many other organs (iii) diabetes decreases the antitumor activity of cisplatin. These data are relevant due to the prevalence of certain tumors in diabetic patients and the importance of cisplatin in chemotherapy; therefore they may indicate the need of more attention in cancer treatment in diabetic patients
92

Efeitos imuno-moduladores de Lactobacillus bulgaricus no câncer colorretal associado à colite / Immuno-modulatory effects of Lactobacillus bulgaricus on colorectal cancer associated with colitis

Denise Sayuri Calheiros da Silveira 27 October 2017 (has links)
O câncer associado à colite (CAC - colitis-associated cancer) é um subtipo de câncer colorretal (CRC) precedido por doenças inflamatórias do intestino (IBD - inflammatory bowel disease). Diante das altas taxas mundiais de incidência e mortalidade do CRC, muitos esforços têm sido movidos pela comunidade científica em busca do desenvolvimento de novas abordagens e estratégias terapêuticas contra esse tipo de câncer. Doenças inflamatórias do intestino estão associadas a um risco aumentado para o desenvolvimento de CRC e evidenciam assim, a complexa conexão entre inflamação e câncer. A microbiota intestinal possui papel central na patogênese de IBD. Há evidente aumento no interesse em investigar maneiras de contornar alterações da resposta imunitária do hospedeiro à disbiose microbiana utilizando suplementos à base de microrganismos vivos. Isso ocorre uma vez que estudos com probióticos têm demonstrado o seu grande potencial imunomodulador. A administração de probióticos tem sido associada à manutenção de períodos prolongados de remissão da doença e à ausência de resistência ao tratamento. No presente trabalho, utilizamos modelo experimental de câncer colorretal associado à inflamação para investigar os efeitos do probiótico Lactobacillus bulgaricus sobre a carcinogênese. Nossos resultados demonstram papel anti-inflamatório de L. bulgaricus na colite induzida por DSS, associado a menores níveis intestinais das citocinas TNF-?, IL-1?, IL-6, IL-17, IL-23. Na carcinogênese, o probiótico induziu menores níveis intestinais das citocinas pró-inflamatórias e levou à redução expressiva do volume tumoral total e tamanho médio de tumores ao final do tratamento. Em conjunto, nossos resultados demonstram papel anti-inflamatório e antitumoral de Lactobacillus bulgaricus na carcinogênese colorretal associada à inflamação. / Colitis-associated cancer (CAC) is a subtype of colorectal cancer (CRC) preceded by inflammatory bowel disease (IBD). Faced with the high global rates of CRC incidence and mortality, many efforts have been made by the scientific community to develop new approaches and therapeutic strategies against this type of cancer. IBDs are associated with an increased risk for CRC development, highlighting the complex connection between inflammation and cancer. The intestinal microbiota has a central role in the pathogenesis of IBD. Currently there is evident increase in interest in investigating manners to circumvent the host\'s immune response to microbial dysbiosis using a supplement based on live microorganisms. This is because studies on probiotics have demonstrated their high immunomodulatory potential. Probiotic administration has been associated with the maintenance of prolonged remission periods of the disease, and with the lack of resistance to treatment. In the present study, we used experimental model of colorectal cancer associated with inflammation to investigate the effects of the probiotic Lactobacillus bulgaricus on carcinogenesis. Our results demonstrate the anti-inflammatory role of L. bulgaricus in DSS-induced colitis, which was associated with lower intestinal levels of the cytokines TNF-?, IL-1?, IL-6, IL-17, IL-23. In carcinogenesis, the probiotic induced lower intestinal levels of the proinflammatory cytokines and led to an expressive reduction of total tumor volume and mean size of tumors at the end of treatment. Taken together, our results demonstrate the anti-inflammatory and antitumor role of Lactobacillus bulgaricus in inflammation-associated colorectal carcinogenesis.
93

Estudo fitoquímico e atividades biológicas das folhas de Pereskia aculeata Miller (Cactaceae)

Pinto, Nícolas de Castro Campos 06 July 2012 (has links)
Submitted by isabela.moljf@hotmail.com (isabela.moljf@hotmail.com) on 2017-05-12T14:35:46Z No. of bitstreams: 1 nicolasdecastrocampospinto.pdf: 2099085 bytes, checksum: a830886c9d165a166c290b802c42fbfc (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-05-12T15:42:58Z (GMT) No. of bitstreams: 1 nicolasdecastrocampospinto.pdf: 2099085 bytes, checksum: a830886c9d165a166c290b802c42fbfc (MD5) / Made available in DSpace on 2017-05-12T15:42:58Z (GMT). No. of bitstreams: 1 nicolasdecastrocampospinto.pdf: 2099085 bytes, checksum: a830886c9d165a166c290b802c42fbfc (MD5) Previous issue date: 2012-07-06 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Pereskia aculeata Miller, popularmente conhecida como ora-pro-nobis, é uma trepadeira arbustiva cujas folhas são empregadas na culinária tradicional de algumas regiões do Brasil. Na medicina popular, são utilizadas como cicatrizantes e no abrandamento de processos inflamatórios. Para contribuir com os estudos sobre P. aculeata, a caracterização fitoquímica de seu extrato bruto metanólico e partições, além do doseamento de fenóis e flavonoides e da pesquisa por compostos indólicos. In vitro, foi avaliada a atividades citotóxica para macrófagos normais, células HL60 e MCF-7 e parasitos do gênero Leishmania pelo método do MTT e a atividade antimicrobiana pelo método de microdiluição em caldo. Além disso, avaliou-se, in vivo, a atividade anti-inflamatória do extrato bruto pelo modelo de edema de orelha induzido pelo óleo de cróton e a atividade antinociceptiva do extrato bruto e partições pelo método de contorções abdominais induzidas pelo ácido acético. Uma vez que a partição hidrometanólica demonstrou maior potencial antinociceptivo, esta também foi estudada pelos testes da formalina, tail-flick e contorções abdominais induzidas pelo ácido acético em animais pré-tratados com pclorofenilalanina (PCPA). O perfil cromatográfico da partição hidrometanólica foi determinado por CLAE. Todas as classes de constituintes químicos pesquisados foram encontrados, à exceção de triterpenos e saponinas. Alcaloides, flavonoides e compostos indólicos foram encontrados em todas as amostras estudadas. A partição em diclorometano apresentou maiores concentrações de fenóis e flavonoides. O extrato bruto e algumas partições demonstraram toxicidade diante de células HL60 e MCF-7. Nenhuma das amostras apresentou toxicidade para macrófagos normais, parasitos do gênero Leishmania e para as estirpes de bactérias testadas. No ensaio do edema de orelha, o extrato bruto apresentou atividade edematogênica via oral, e a análise histológica dos fragmentos de orelha sugeriu que o edema não deve ter sido causado por um aumento do processo inflamatório. O estudo mais aprofundado da partição hidrometanólica revelou que seu mecanismo de ação antinociceptivo se dá a nível periférico e central, não associado à ativação de receptores opióides ou à liberação e síntese de serotonina. A análise por CLAE revelou a presença de substâncias cujo espectro UV é típico de compostos indólicos. Segundo a literatura, as folhas de P. aculeata são ricas em triptofano, aminoácido precursor da serotonina, um dos mediadores inflamatórios vasodilatores e um dos neurotransmissores que atuam inibindo a nocicepção a nível central. Nas plantas, o triptofano dá origem aos alcalóides indólicos, compostos estruturalmente semelhantes à serotonina. Assim, levanta-se a hipótese de que alcalóides indólicos estejam contribuindo para os efeitos observados in vivo para o extrato bruto e a partição hidrometanólica. / Pereskia aculeata Miller, known as ora-pro-nobis, is a climbing shrub which leaves are used in tradicional cuisine in Brazil. The leaves are used in folk medicine in skin wound healing and to treat inflammation. To contribute to the studies on P. aculeata, the phytochemical characterization of its crude methanol extract and partitions, the quantification of phenols and flavonoids and the search for indoles compounds were carried out. In vitro, we tested the cytotoxic activity to normal macrophages, HL60 and MCF-7 cells and parasites of the genus Leishmania by MTT method and also antimicrobial activity by microdilution method. Furthermore, we evaluated the in vivo anti-inflammatory activity of the crude extract by the model of ear edema induced by croton oil and antinociceptive activity of crude extract and partitions by acetic acidinduced writhing test. Since hydromethanolic partition showed the greatest antinociceptive potential, it was also studied by acetic acid-induced writhing test in animals pretreated with p-chlorophenylalanine (PCPA), formalin and tail-flick tests. The chromatographic profile of the hydromethanolic partition was determined by HPLC. All classes of chemical constituents investigated were found, with the exception of triterpenes and saponins. Alkaloids, flavonoids and indoles were found in all samples. Dichloromethane partition showed higher phenols and flavonoids contents. Crude extract and some partitions showed cytotoxicity against HL60 and MCF-7 cells. None of the samples showed cytoxicity against normal macrophages, Leishmania parasites or bacteria strains. Crude extract showed edematogenic activity in croton oil test when administered orally, but the histological analysis of the ears suggested that the edema should not have been caused by an increase in inflammatory process. The study further revealed that the antinociceptive mechanism of hydromethanolic partition was peripheral and central, but not related to opioid receptors or serotonin synthesis and release. HPLC analysis revealed the presence of indoles in this partition. The leaves of P. aculeata are rich in tryptophan, a serotonin precursor. Serotonin is a vasodilator and a neurotransmitter which inhibits central nociception. In plants, tryptophan leads to indole alkaloids, structurally similar to serotonin. Thus, we hypothesize that indole alkaloids are involved in the in vivo activities observed for crude extract and hydrometanolic partition.
94

SÍNTESE E ATIVIDADES ANTIOXIDANTE E ANTITUMORAL DE 5´-ARILSELENO AZIDOTIMIDINA

Souza, Diego de 30 March 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The synthesis of compounds that use a nucleoside as the base structure, has an intense field application. Among these compounds, the most known nowadays is azydothymidine or zidovudine, a drug which was first synthesized to work against tumor processes. However, it was discovered that it could take action to viral combat and now it is the drug of choice in the treatment of acquired immunodeficiency syndrome (AIDS). On the other hand, organochalcogens compounds have been calling the attention of the scientific community, mainly because of their potential in biological molecules containing these atoms. Considering this last factor and aiming to explore the structural basis of nucleosides and biological influences that changes in the 5' position of the deoxyribose ring of AZT would promote, it was planned through an efficient and accessible synthetic route to produce a new series of nucleosides, the 5'-arylseleno azidothymidine, which had the insertion of the selenium atom connected to different aril groups. Moreover, the series of selenium derivatives were evaluated for their toxicological potential for oxidative stress (TBARS and thiol peroxidase), where the compounds 5´-p-methylseleno azidothymidine 3b and 5´-p-chloroseleno azidothymidine (3h) had the results of this series, with potential as antioxidant agent. After this, the compounds 3b and 3h were tested against culture cell lines of bladder cancer (5637). The tests aimed to assess the cytotoxicity, cell morphology, apoptosis analysis and gene expression. The results showed that the compounds 3b and 3h present apoptotic profile, additionally they seem to modulate the expression of anti-apoptotic gene. The results obtained indicate that the compounds 3b and 3h in addition of presenting an antioxidant potential, have a pro-apoptotic profile, even more effective than AZT itself. Considering all the results presented, it was concluded that this new nucleoside serie has great antitumor potential and can be used as a chemopreventive, combined to the antioxidant potential. / A síntese de compostos que usam como base a estrutura de nucleosídeos é um campo que possui uma intensa aplicação biológica. Dentre estes compostos, o mais conhecido é a azidotimidina ou zidovudina (AZT), um fármaco que teve sua síntese inicial voltada para o combate de processos tumorais. No entanto, descobriu-se que este poderia agir no combate viral e hoje é o fármaco de primeira escolha no tratamento da síndrome da imunodeficiência adquirida. Adicionalmente, compostos organocalcogênio, principalmente compostos de selênio, despertam a atenção da comunidade científica principalmente devido as suas potencialidades biológicas. Dessa forma, a fim de explorar a base estrutural dos nucleosídeos e as influências biológicas que modificações na posição 5´ do anel da desoxirribose do AZT promoveriam, planejou-se através de uma eficiente rota sintética, a síntese de uma nova série de nucleosídeos, os 5´-arilseleno azidotimidina, que apresentaram a inserção do átomo de selênio ligados a diferentes grupamentos arílicos. Com o objetivo de realizarmos uma seleção dos melhores compostos da série de selenonuclesídeos, avaliamos o parâmetro toxicológico para o estresse oxidativo (TBARS e tiol peroxidase) destes compostos. Onde, os compostos 5´-p-metilseleno azidotimidina (3b) e 5´-p-cloroseleno azidotimidina (3h) apresentaram os resultados mais promissores, apresentando inclusive perfil como agente antioxidante. Dessa forma, após realizarmos a triagem, os compostos 3b e 3h tiveram suas atividades testadas frente à cultura celular de linhagem de câncer de bexiga (5637). Os testes buscaram avaliar os parâmetros de citotoxicidade, morfologia celular, análise apoptótica e a expressão gênica. Os resultados obtidos mostraram que os compostos 3b e 3h apresentaram perfil apoptótico, além de serem capazes de modular a expressão do gene anti-apoptótico. Por fim, os resultados obtidos, apontam que os compostos 3b e 3h além de apresentarem um perfil antioxidante, possuem ação pró-apoptótica mais eficientes do que o próprio AZT. Dessa forma, considerando todos os resultados obtidos, foi possível concluir que essa nova série de nucleosídeos apresenta potencial antitumoral, podendo ser usado quimiopreventivamente, aliado ao perfil antioxidante.
95

Estudo fitoquímico e ensaios biológicos de Didymopanax morototoni (Araliaceae) / Phytochemical study and biochemical essays of Didymopanax morototoni (Araliaceae)

Costa, Ana Lucila dos Santos 14 December 2011 (has links)
The species Didymopanax morototoni (araliaceae), known as morototó is used in folk medicine in some countries of Latin America and Brazil is used to regulate menstrual flow, however, studies of its chemical composition were not reported. This study evaluated the potential of extracts and fractions of D. morototoni for the control of tropical disease vectors, Aedes aegypti larvae, the mollusk Biomphalaria glabrata, inhibition of reverse transcriptase, antitumor activity against the NCI-H292 cells and K562, and as well as the elucidation of the six active ingredients. The plant material was collected in the municipality of Pilar, Alagoas State, and was subjected to a phytochemical study led by the molluscicidal bioassay. The crude extract of the plant was obtained by extraction with 90% ethanol and subjected to fractionation with solvents of increasing polarity. The structural elucidation of compounds was based on the analysis of IR spectra and NMR, experiments including 1D and 2D. Were isolated from the chloroform fraction of the stem bark acid 3-O-β-D-xilopiranosil (1→3) β- glucopyranosyl-olean-12-en-28-oic acid (DMCC1), the mixture of 3-O-β-D-glucopyranosylsitosterol and 3-O-β-D-glucopyranosyl-stigmasterol (DMCC2) and acid 3-O-β-Dglucopyranosyl (1→2) β - arabinopiranosil (4→1) β-glucopyranosyl-olean-12-en-28-oicacid (DMCC3), and the hexane fraction of the wood the mixture of steroids stigmasterol and β-sitosterol (DMM1), oleanolic acid (DMM2), ursolic acid (DMM3). The ethanolic leaf extract of D. morototoni was active against the larvae of Aedes aegypti with LC50 55.0264mg. mL-1. The ethanolic extract of the wood, stem bark and root have shown molluscicidal activity against the snail Biomphalaria glabrata. The ethanol extract of the root exhibited higher molluscicidal activity with LC50 5.336 mg. mL-1. among the compounds isolated the triterpene glycosides and DMCC1 DMCC3 showed molluscicidal activity with LC50 1.012 and 0.906 mg. mL-1 respectively. The ethanol extracts of leaf and root bark inhibited the action of the enzyme reverse transcriptase (RT) 100% and 51% respectively at a concentration of 50 mg. mL-1. Although the stem bark extract did not show significant inhibition of TR to the hexane fraction showed 79.62% inhibitory activity of 50 mg. mL-1. All substances isolated from D. morototoni inhibited RT, the mixture of 3-O-β-D-glucopyranosyl-sitosterol and 3-O-β-D-glucopyranosyl-stigmasterol showed the greatest potential inhibitor of TR with 70.41% at 10 mg. mL-1. For testing the antitumor activity was the best result for the ethanolic extract of stem bark with IC50 3.44 mg. mL-1 and K-562 IC50 8.01 mg. mL-1 in NCI-H292. This extract only the chloroform fraction was active with IC50 7.97 and 13.32 mg. mL-1 for NCIH292 cells and K562 respectively. The extract and fractions derived from the stem bark showed activity imunomudulatória with a percentage ranging from 64% to 99.25% 100 mg.mL-1. The results of phytochemical and biological activity contribute to propose the use of this plant molluscicide agent, antiviral and antitumor. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A espécie Didymopanax morototoni (Araliaceae), conhecida como morototó, é utilizada na medicina popular de alguns países da América Latina e no Brasil é usado para regular o fluxo menstrual, no entanto, estudos de sua composição química não foram relatados. O presente trabalho avaliou o potencial dos extratos e frações de D. morototoni para o controle dos vetores de doenças tropicais, larvas de Aedes aegypti, do molusco Biomphalaria glabrata, inibição da transcriptase reversa, atividade antitumoral contra as células NCI-H292 e K562 e bem como a elucidação de seis dos princípios ativos. O material vegetal foi coletado no município de Pilar, Estado de Alagoas, e foi submetido a um estudo de fitoquímica guiado pelo bioensaio moluscicida. O extrato bruto da planta foi obtido pela extração com etanol 90% e submetido a fracionamento com solventes de polaridade crescente. A elucidação estrutural dos compostos foi feita com base na análise dos espectros no IV e de RMN, incluindo experimentos 1D e 2D. Foram isolados da fração clorofórmica da casca do caule os o ácido 3-O-β-D- xilopiranosil (1→3) β- glicopiranosil-oleano-12-en-28-oico (DMCC1), a mistura de 3-O-β-D-glicopiranosil-sitosterol e 3-O-β-D-glicopiranosil-estigmasterol (DMCC2) e o ácido 3-O-β-D-glicopiranosil (1→2) β - arabinopiranosil (4→1) β-glicopiranosil- oleano-12-en-28-oico (DMCC3), e da fração hexânica da madeira a mistura dos esteróides estigmasterol e β-sitosterol (DMM1), ácido oleanólico (DMM2), ácido ursólico (DMM3). O extrato etanólico da folha de D. morototoni foi ativo frente às larvas de Aedes aegypti com CL50 55,0264 μg. mL-1. Os extratos etanólico da madeira, casca do caule e raiz apresentaram atividade moluscicida frente ao caramujo Biomphalaria glabrata. O extrato etanólico da raiz exibiu maior atividade moluscicida com CL50 5,336 μg. mL-1. Dentre os compostos isolados os triterpenos glicosilados DMCC1 e DMCC3 apresentaram atividade moluscicida com CL50 1,012 e 0,906 μg. mL-1 respectivamente. Os extratos etanólico da folha e da casca da raiz inibiram a ação da enzima transcriptase reversa (TR) 100% e 51% respectivamente na concentração de 50 μg. mL-1. Apesar do extrato da casca do caule não apresentar inibição significativa da TR a fração hexânica mostrou 79,62 % de atividade inibitória 50 μg. mL-1. Todas as substâncias isoladas de D. morototoni inibiram a TR, a mistura de 3-O-β-D-glicopiranosil-sitosterol e 3-O-β-D-glicopiranosil-estigmasterol apresentou maior potencial inibidor da TR com 70,41% a 10 μg. mL-1. Para o ensaio da atividade antitumoral o melhor resultado foi para extrato etanólico da casca do caule com CI50 3,44 μg. mL-1 em K-562 e CI50 8,01 μg. mL-1 em NCI-H292. Desse extrato apenas a fração clorofórmica foi ativa com CI50 13,32 e 7,97 μg. mL-1 para as células NCI-H292 e K562 respectivamente. O extrato e frações oriundas da casca do caule exibiram atividade imunomudulatória com percentual variando de 64% a 99,25% 100 mg. mL-1. Os resultados da atividade biológica e fitoquímica contribuem para propor a utilização dessa planta como agente moluscicida, antiviral e antitumoral.
96

Ramanova spektroskopie biologicky aktivních látek a protinádorových léčiv / Raman spectroscopy of biologically active species and antitumor drugs

Třeštíková, Liběna January 2009 (has links)
SERRS spektra of biological materials are very komplex, because they consist of signals from all molecules present in cells. In this text are presented SERRS spektra of antitumor drugs and its komplex with DNA. Experimental are rated on doxorubicin and another antitumor druha and on study of theirs potential by treatment for tumors. Doxorubicin belong to clase antracycline antibiotics and is used for stop of tumor cells reproduction. Scientists found still new ways, new drugs. SERRS is one of possibilities for study of this drugs and theirs interaction with DNA.
97

ATP Synthase: A Molecular Therapeutic Drug Target for Antimicrobial and Antitumor Peptides

Ahmad, Zulfiqar, Okafor, Florence, Azim, Sofiya, Laughlin, Thomas F. 01 May 2013 (has links)
In this review we discuss the role of ATP synthase as a molecular drug target for natural and synthetic antimicrobial/ antitumor peptides. We start with an introduction of the universal nature of the ATP synthase enzyme and its role as a biological nanomotor. Significant structural features required for catalytic activity and motor functions of ATP synthase are described. Relevant details regarding the presence of ATP synthase on the surface of several animal cell types, where it is associated with multiple cellular processes making it a potential drug target with respect to antimicrobial peptides and other inhibitors such as dietary polyphenols, is also reviewed. ATP synthase is known to have about twelve discrete inhibitor binding sites including peptides and other inhibitors located at the interface of α/β subunits on the F1 sector of the enzyme. Molecular interaction of peptides at the β DEELSEED site on ATP synthase is discussed with specific examples. An inhibitory effect of other natural/synthetic inhibitors on ATP is highlighted to explore the therapeutic roles played by peptides and other inhibitors. Lastly, the effect of peptides on the inhibition of the Escherichia coli model system through their action on ATP synthase is presented.
98

ATP Synthase: A Molecular Therapeutic Drug Target for Antimicrobial and Antitumor Peptides

Ahmad, Zulfiqar, Okafor, Florence, Azim, Sofiya, Laughlin, Thomas F. 01 May 2013 (has links)
In this review we discuss the role of ATP synthase as a molecular drug target for natural and synthetic antimicrobial/ antitumor peptides. We start with an introduction of the universal nature of the ATP synthase enzyme and its role as a biological nanomotor. Significant structural features required for catalytic activity and motor functions of ATP synthase are described. Relevant details regarding the presence of ATP synthase on the surface of several animal cell types, where it is associated with multiple cellular processes making it a potential drug target with respect to antimicrobial peptides and other inhibitors such as dietary polyphenols, is also reviewed. ATP synthase is known to have about twelve discrete inhibitor binding sites including peptides and other inhibitors located at the interface of α/β subunits on the F1 sector of the enzyme. Molecular interaction of peptides at the β DEELSEED site on ATP synthase is discussed with specific examples. An inhibitory effect of other natural/synthetic inhibitors on ATP is highlighted to explore the therapeutic roles played by peptides and other inhibitors. Lastly, the effect of peptides on the inhibition of the Escherichia coli model system through their action on ATP synthase is presented.
99

Une nouvelle approche synthétique vers les kingianines : préparation d’intermédiaires clés et d’analogues simplifiés / A novel synthetic approach towards the kingianins : preparation of key intermediates and simplified analogues

Ly, Kieu Dung 26 September 2019 (has links)
Cette thèse décrit une nouvelle approche pour la synthèse des kingianines, une famille d'inhibiteurs de la protéine anti-apoptotique Bcl-xL, isolés à partir de l'écorce d'Endiandra kingiana. Nous avons proposé des solutions pour éviter les problèmes de réactivité et de sélectivité rencontrés lors des études précédentes. Une stratégie reposant sur une réaction de cycloaddition [2+2] a été appliquée pour former le système bicyclique intermédiaire, au lieu d’une cascade biomimétique de réactions d’électrocyclisation. Ce choix a été efficace et un seul diastéréoisomère a été obtenu. L’utilisation d’un diénophile appauvri en électrons et d’un diène riche en électrons dans l’étape clé a permis la réalisation d’une réaction de Diels-Alder dans des conditions classiques, avec une bonne régiosélectivité. Nous avons réussi à synthétiser plusieurs analogues simplifiés des kingianines. Leur activité biologique sur les protéines Bcl-2, Bcl-xL et Mcl-1 sera évaluée dans un futur proche. / This dissertation describes a new approach for the synthesis of kingianins, a family of inhibitors of the anti-apoptotic protein BclxL, which were isolated from the bark of Endiandra kingiana. We have proposed solutions to address the problems of reactivity and selectivity that had been met in previous studies. A strategy involving a [2+2] cycloaddition reaction was applied for the formation of the intermediate bicyclic system, instead of a biomimetic electrocyclisation cascade. This choice was efficient and a single diastereoisomer was obtained. The use of an electron-poor dienophile and an electron-rich diene in the key step allowed for a Diels-Alder reaction to proceed under classic conditions, with good regioselectivity. We have succeeded in synthesising several simplified kingianin analogues. Their biological activities on the Bcl-2, Bcl-xL and Mcl-1 proteins will be evaluated in the near future.
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Studies on pharmacological activities of the cauliflower mushroom Sparassis crispa / ハナビラタケの薬理活性に関する研究

Kimura, Takashi 25 November 2013 (has links)
京都大学 / 0048 / 新制・論文博士 / 博士(農学) / 乙第12794号 / 論農博第2790号 / 新制||農||1019(附属図書館) / 学位論文||H25||N4806(農学部図書室) / 30813 / (主査)教授 栗原 達夫, 教授 植田 和光, 教授 平竹 潤 / 学位規則第4条第2項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

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