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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.
121

Murine L929 cell and its tumour necrosis factor (TNF)-resistant variants: biochemical characterization with respect to mechanism of TNF action.

January 1995 (has links)
by Kwan, Leo. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1995. / Includes bibliographical references (leaves 108-116). / Abstract --- p.i / Achnowledgment --- p.ii / List of abbreviations --- p.iii / List of table and figures --- p.v / Table of contents --- p.vi / Chapter CHAPTER 1 --- INTRODUCTION / Chapter 1.1 --- THE DISCOVERY OF TUMOUR NECROSIS FACTOR (TNF) --- p.1 / Chapter 1.2 --- THE MOLECULE AND ITS RECEPTORS --- p.1 / Chapter 1.3 --- THE BIOLOGICAL ACTIVITIES OF TNF --- p.3 / Chapter 1.4 --- STUDIES ON THE CYTOTOXIC MECHANISM OF TNF --- p.4 / Chapter 1.5 --- A TENTATIVE MECHANISM OF TNF CYTOTOXICITY --- p.11 / Chapter 1.6 --- THE GLUTATHIONE SYSTEM : A CELLULAR PROTECTIVE MECHANISM AGAINST OXIDATIVE STRESS …… --- p.12 / Chapter 1.7 --- OBJECTIVE AND STRATEGY OF THIS STUDY --- p.16 / Chapter CHAPTER 2 --- MATERIALS AND APPARATI / Chapter 2.1 --- CELL LINES --- p.19 / Chapter 2.2 --- "ISOLATION, MAINTENANCE AND SUBCULTURE OF CELL LINES" --- p.19 / Chapter 1. --- Plain RPMI-1640 medium / Chapter 2. --- Penicillin-streptomycin solution / Chapter 3. --- Foetal bovine serum / Chapter 4. --- Complete RPMI-1640 medium / Chapter 5. --- Trypsin-ethylenediaminetetraacetate solution / Chapter 6. --- Phosphate buffered saline / Chapter 7. --- Cycloheximide / Chapter 8. --- Actinomycin D / Chapter 9. --- Trypan blue stain / Chapter 10. --- Neutral red stain / Chapter 11. --- Recombinant human tumour necrosis factor / Chapter 12. --- Cell culture plates and flasks / Chapter 2.3 --- GROWTH CHARACTERISTIC --- p.22 / Chapter 1. --- Tritiated Thymidine / Chapter 2. --- Tritiated Leucine / Chapter 3. --- Trichloroacetic acid / Chapter 4. --- Scintillation cocktail / Chapter 2.4 --- "RESPONSE TOWARDS ANTICANCER DRUGS, CYTOTOXIC AGENTS, AND ENZYME MODULATORS" --- p.23 / Chapter 1. --- N-acetyl-DL-homocysteinethiolactone / Chapter 2. --- Diethyldithiocarbamic acid / Chapter 3. --- Doxorubicin / Chapter 4. --- Acivicin / Chapter 5. --- Ethacrynic acid / Chapter 6. --- "L'Buthionine-[S,R]-sulfoximine" / Chapter 7. --- Hydrogen peroxide / Chapter 8. --- Methotrexate / Chapter 9. --- Menadione / Chapter 2.5 --- CULTURE OF BACTERIAL CELLS --- p.27 / Chapter 1. --- Ampicillin stock solution / Chapter 2. --- Chloramphenicol stock solution / Chapter 3. --- Tetracycline stock solution / Chapter 4. --- Luria-Bertani medium / Chapter 5. --- LB with ampicillin / Chapter 6. --- SOB medium / Chapter 7. --- SOB medium with ampicillin / Chapter 8. --- SOC medium / Chapter 9. --- SB medium / Chapter 10. --- SB medium with ampicillin / Chapter 11. --- Agar plates / Chapter 2.6 --- PREPARATION OF DNA PROBES FROM BACTERIAL CLONES --- p.29 / Chapter 1. --- FlexiPrep Kit / Chapter 2. --- Restriction endonucleases / Chapter 3. --- GeneClean® II Kit / Chapter 4. --- cDNA clones for making DNA probes / Chapter 5. --- TrisHCl EDTA buffer / Chapter 2.7. --- ELECTROPHORESIS OF DNA --- p.31 / Chapter 1. --- EDTA stock solution / Chapter 2. --- Tris acetate EDTA electrophoresis buffer / Chapter 3. --- Tris borate EDTA electrophoresis buffer / Chapter 4. --- Ethidium bromide / Chapter 5. --- DNA molecular size markers / Chapter 6. --- TAE/TBE agarose gel slab / Chapter 2.8 --- CONSTRUCTION OF MURINE TNFR1 PARTIAL cDNA CLONE --- p.33 / Chapter 1. --- Frist strand cDNA synthesis Kit / Chapter 2. --- Murine TNFR1 forward and reverse primers / Chapter 3. --- Polymerase chain reaction reagents / Chapter 4. --- Cloning vector / Chapter 5. --- Modifing enzymes / Chapter 6. --- T7 SequencingTM Kit / Chapter 7. --- Acrylamide/bis gel stock solution / Chapter 8. --- Urea / Chapter 9. --- TEMED and ammonium persulphate / Chapter 10. --- β-Galactosidase colour test reagents / Chapter 11. --- TFB solution / Chapter 12. --- DnD solution / Chapter 2.9. --- RADIOLABELLING OF DNA PROBES --- p.35 / Chapter 1. --- Oligolabelling kit / Chapter 2. --- Redivue [α-32P] dCTP / Chapter 3. --- PUSH column / Chapter 2.10 --- EXTRACTION OF TOTAL RNA FROM CELL LINES --- p.36 / Chapter 1. --- N-Lauroylsarcosine / Chapter 2. --- 2M sodium acetate (pH48) / Chapter 3. --- Phenol / Chapter 4. --- Isopropanol / Chapter 5. --- Ethanol / Chapter 6. --- Extraction buffer / Chapter 7. --- Chloroform / Chapter 8. --- Isoamyl alcohol / Chapter 2.11 --- HYBRIDIZATION AND NORTHERN ANALYSIS --- p.37 / Chapter 1. --- 20XSSC / Chapter 2. --- 5X formaldehyde running buffer / Chapter 3. --- RNA sample buffer / Chapter 4. --- 10X RNA loading buffer / Chapter 5. --- Formaldehyde slab gel / Chapter 6. --- Hybond®-N membrane / Chapter 7. --- Immobilon®-N membrane / Chapter 8. --- Salmon sperm DNA / Chapter 9. --- Sodium dodecyl sulphate / Chapter 10. --- Dextran sulphate / Chapter 11. --- Kodak Biomax MR and X-OMAT films and developing kits / Chapter 2.12 --- APPARATI USED --- p.39 / Chapter CHAPTER 3 --- METHODS / Chapter 3.1 --- ISOLATION AND MAINTENANCE OF TNF RESISTANT L929 CELLS --- p.40 / Chapter 3.1.1 --- Culture of L929 cells / Chapter 3.1.2 --- Trypan blue exclusion test / Chapter 3.1.3 --- Isolation of TNF-resistant variants of L929 / Chapter 3.1.4 --- Verification of the TNF-resistant trait of rL929 / Chapter 3.1.5 --- Neutral red uptake assay / Chapter 3.2 --- COMPARING L929 AND rL929 CELLS IN TERMS OF GROWTH CHARACTERISTICS --- p.43 / Chapter 3.2.1 --- Doubling time / Chapter 3.2.2 --- Rate of protein synthesis / Chapter 3.2.3 --- Rate of DNA synthesis / Chapter 3.3 --- COMPARING L929 AND rL929 CELLS IN TERMS OF RESPONSE TOWARDS DIFFERENT ENZYME INHIBITORS AND CYTOTOXIC AGENTS --- p.44 / Chapter 3.3.1 --- TNF cytotoxicity on L929 and rL929 cells --- p.44 / Chapter 3.3.2 --- Effects of inhibitors of gene transcription and protein synthesis on TNF cytotoxicity on L929 and rL929 cells --- p.44 / Chapter 3.3.3 --- Cytotoxic effect of hydrogen peroxide and menadione on L929 and rL929 cells --- p.44 / Chapter 3.3.4 --- TNF cytotoxicity on L929 and rL929 cells: effect of N-acetyl homocysteine thiolatone --- p.45 / Chapter 3.3.4.1 --- The tolerant limit of AHCT / Chapter 3.3.4.2 --- Effect of AHCT on TNF cytotoxicity / Chapter 3.3.5 --- TNF cytotoxicity on L929 and rL929 cells: effect of diethyldithiocarbamate --- p.46 / Chapter 3.3.5.1 --- The tolerant limit of DEDTC / Chapter 3.3.5.2 --- Effect of DEDTC on TNF cytotoxicity / Chapter 3.3.6 --- TNF cytotoxicity on L929 and rL929 cells: effect of buthionice sulfoximine --- p.47 / Chapter 3.3.6.1 --- The tolerant limit of BSO / Chapter 3.3.6.2 --- Effect of BSO on TNF cytotoxicity / Chapter 3.3.7 --- TNF cytotoxicity on L929 and rL929 cells: effect of Acivicin --- p.47 / Chapter 3.3.7.1 --- The tolerant limit of acivicin / Chapter 3.3.7.2 --- Effect of acivicin on TNF cytotoxicity / Chapter 3.3.8 --- TNF cytotoxicity on L929 and rL929 cells: effect of ethacrynic acid --- p.48 / Chapter 3.3.8.1 --- The tolerant limit of ethacrynic acid / Chapter 3.3.8.2 --- Effect of ethacrynic acid on TNF cytotoxicity / Chapter 3.3.9 --- Cytotoxic effect of doxorubicin on L929 and rL929 cells --- p.49 / Chapter 3.3.10 --- TNF cytotoxicity of L929 cells: effect of N-acetyl cysteine --- p.49 / Chapter 3.3.11 --- Cytotoxic effect of methotrexate on L929 and rL929 cells --- p.50 / Chapter 3.3.12 --- Cytotoxic effect of hyperthermia on L929 and rL929 cells --- p.50 / Chapter 3.4 --- NORTHERN ANALYSIS AND HYBRIDIZATION --- p.51 / Chapter 3.4.1. --- Preparing RNA blots --- p.51 / Chapter 3.4.1.1 --- Extraction of total RNA from cells / Chapter 3.4.1.2 --- Making equal loading of RNA samples in formaldehyde gel electrophoresis / Chapter 3.4.1.3 --- Northern blotting of RNA / Chapter 3.4.2. --- Preparation of cDNA probes --- p.53 / Chapter 3.4.2.1 --- Preparing plasmids from A TCC clones / Chapter 3.4.2.2 --- Preparing TNFR1 probe from first-strand cDNA of L929 cells / Chapter 1. --- Construction of recombinant clone from the PCR product of TNFRl fragment / Chapter 2. --- Transforming the recombinant vector into JM109 host / Chapter 3. --- Sequencing of PCR product for identity confirmation / Chapter 3.4.2.3 --- Preparing DNA inserts from plasmids / Chapter 3.4.3 --- Radiolabelling of cDNA probes --- p.56 / Chapter 3.4.4 --- Hybridization of radioactive probes to RNA blots --- p.57 / Chapter CHAPTER 4 --- RESULTS AND DISCUSSIONS / Chapter 4.1 --- ISOLATION OF TNF-RESISTANT VARIANTS OF L929 CELLS --- p.58 / Chapter 4.1.1 --- Single cell subcloning of TNF-resistant L929 variants / Chapter 4.1.2 --- Growth rates of L929 and rL929 cells / Chapter 4.1.3 --- Rate of protein synthesis in L929 and rL929 cells / Chapter 4.1.4 --- Rate of DNA synthesis in L929and rL929 cells / Chapter 4.2 --- EFFECT OF INHIBITORS OF GENE TRANSCRIPTION AND PROTEIN SYNTHESIS ON TNF CYTOTOXICITY ON L929 AND rL929 CELLS --- p.67 / Chapter 4.3 --- RESPONSE OF L929 AND rL929 CELLS TOWARDS VARIOUS CYTOTOXIC AGENTS --- p.70 / Chapter 4.3.1 --- "Response towards methotrexate, an anti-metabolite used in cancer treatment" / Chapter 4.3.2 --- "Response towards doxorubicin, an chemotherapeutic agent used in cancer treatment" / Chapter 4.3.3 --- "Response towards menadione, a cytotoxic agent known to generate free radicals inside cells" / Chapter 4.3.4 --- Response towards hydrogen peroxide: a highly oxidative agent / Chapter 4.3.5 --- "Response towards hyperthermia, a treatment known to exert oxidative stress on cells" / Chapter 4.4 --- EFFECTS OF MODULATORS OF CYTOSOLIC SUPEROXIDE DISMUTASE ON TNF CYTOTOXICITY ON L929 and rL929 CELLS --- p.77 / Chapter 4.5 --- EFFECT OF MODULATORS OF GLUTATHIONE METABOLISM ON TNF CYTOTOXICITY ON L929 AND rL929 CELLS --- p.82 / Chapter 4.5.1 --- "Effects of L-buthionine [S,R] sulfoximine, an inhibitor of glutathione synthesis" --- p.82 / Chapter 4.5.2 --- "Effect of N-acetyl cysteine, a cysteine derivative" --- p.84 / Chapter 4.5.3 --- "Effects of acivicin , an inhibitor of GSH reuptake and recycle" --- p.85 / Chapter 4.5.4 --- "Effect of ethacrynic acid, an inhibitor of glutathione S- transferase" --- p.87 / Chapter 4.6 --- GENE EXPRESSION IN L929 AND rL929 CELLS IN THE COURSE OF TNF CHALLENGE --- p.89 / Chapter 4.6.1 --- Isolation of total RNA from L929 and rL929 cells --- p.89 / Chapter 4.6.2 --- Preparation of DNA probes for hybridization --- p.89 / Chapter 4.6.3 --- Hybridization of specific probes on RNA blots --- p.90 / Chapter 4.6.3.1 --- Expression of heat shock protein --- p.70 / Chapter 4.6.3.2 --- Expression of the p55 TNF receptor / Chapter 4.6.3.3 --- Expression of glutathione reductase / Chapter 4.6.3.4 --- Expression of glutathione S-transferase pi / Chapter 4.7 --- DISCUSSIONS OF THE EXPERIMENTAL RESULTS --- p.97 / Chapter CHAPTER 5 --- GENERAL DISCUSSION --- p.104 / APPENDIX / Generation of the TNF receptor 1 cDNA probe --- p.106 / REFERENCES --- p.108
122

Avaliação dos efeitos antitumorais de extratos brutos produzidos por fungos endofíticos isolados de Eugenia jambolana em células de hepatocarcinoma murino (Hepa-1c1c7) /

Lopes, Patrícia da Silva. January 2015 (has links)
Orientador: Christiane Pienna Soares / Coorientador: Cleverton Roberto de Andrade / Banca: Angela Regina Araújo / Banca: Raquel Alves dos Santos / Resumo: carcinoma hepatocelular (CHC) é um tumor primário mais frequente do fígado, sendo a terceira causa de mortalidade por câncer. Dentre os tumores hepáticos primários o CHC é responsável por quase 90% dos casos. Frente a busca para o desenvolvimento da produção de novos fármacos derivados de produtos naturais, os fungos endofíticos apresentam-se como fontes promissoras. Estudos recentes mostraram que os extratos de fungos endofíticos tem várias atividades, como propriedades anti-tumorais. O objetivo do presente estudo foi avaliar a capacidade de citotóxica dos extratos brutos produzidos pelos fungos endofíticos isolados de Eugenia jambolana nas linhagens hepatocarcinoma murinho (Hepa 1c1c7), linhagem humana de hepatocarcinoma (Hep G2) e queratinócito normal de pele (HaCat) e verificar a indução de apoptose, atividade de caspase, genotoxicidade, mutagenicidade e identificar a distribuição no ciclo celular. Nossos resultados indicam que ambos os extratos apresentaram atividade inibidoras. O extrato bruto do fungo Pseudofusicoccum stromaticum (Ej-fm1) apresentou maior seletividade para Hepa1c1c7, apresentando CI50 de 58 μg/mL, com uma inibição celular de 63,4% e 38,4% para as concentrações de 100 μg/mL e 50 μg/mL. Enquanto HepG2 e HaCat não apresentaram morte celular significativa. O extrato de Neofusicoccum sp. (Ej-fv1) induziu alta citotoxicidade, apresentando inibição celular 67,83% apenas na concentração de 100 μg/mL com um valor de CI50 de 89 μg/mL. HepG2 e HaCaT demonstraram inibição celular significativa (38,4% e 43,5%, respectivamente), mas também apenas na maior concentração (100 μg/mL). Na avaliação de apoptose usando o método Hoechst/Iodeto de propídeo em Hepa1c1c7, o extrato (Ej-fm1) apresentou diferença estatística para a presença de apoptose tardia, bem como necrose. Mas para o extrato (Ej-fv1) houve morte celular significativa apenas na concentração de 100 μg/mL para a apoptose precoce e... / Abstract: Hepatocellular carcinoma (HCC) is more frequent primary liver cancer, and third most commum cause of cancer mortality. Among primary liver tumors HCC is responsible for nearly 90% of cases. Compared to search for the development of production of novel drugs from natural products, the endophytic fungi have been presented as promising sources. Recent studies showed that extracts of endophytic fungi have various activities, such as, properties antitumor. The aim of this study was to evaluate cytotoxicity capacity of the crude extract isolated endophytic fungus ripe fruit, Ej-fm1 and unripe fruit, Ej-FV1 Eugenia jambolana in Murine hepatoma cell (Hepa 1c1c7), Human hepatocarcinoma cell line (Hep G2) and spontaneously immortalized human keratinocytes (HaCaT) and check the induction of apoptosis, caspase activity, genotoxic activity, mutagenic and distribution of cell cycle. Our findings indicate that demonstrated that both extracts showed inhibitory activities. The crude extract from Pseudofusicoccum stromaticum (Ej-fm1) possessed more selectivity against Hepa1c1c7 showed IC50, value of 58 μg/mL, having a cellular inhibition 63.4% and 38.4% for the concentration 100μg / ml and 50μg/ml. While for HepG2 and HaCat, no significant cell death. The extract of Neofusicoccum sp.(Ej-fv1) induced high cytotoxicity, showed cellular inhibition 67.83% just at concentration 100μg/ml with IC50 value of 89 μg/mL. HepG2 and HaCaT cell also showed significant inhibition (38.4% and 43.5%, respectively) also only at the highest concentration. To evaluate apoptosis using Hoechst/ Propidium iodide method in Hepa1c1c7 cells, the extract (Ej-fm1) showed statistical difference for presence of late apoptosis, as well as necrosis. But the extract (Ej-fv1) there are significant cell death only in the concentration of 100μg / mL for early apoptosis and necrosis, noting a concentration-response for early apoptosis. About the analyses of cell death mechanisms, we ... / Mestre
123

Avaliação in vitro da citotoxicidade de monômeros, plastificante e produtos de degradação liberados a partir de resinas para reembasamento imediato /

Chaves, Carolina de Andrade Lima. January 2009 (has links)
Resumo: O presente estudo teve como objetivo avaliar o efeito citotóxico dos monômeros isobutil metacrilato (IBMA) e 1,6 - Hexanediol dimetacrilato (1,6 - HDMA), do plastificante di-n-butil ftalato (DBP), e dos produtos de degradação ácido metacrílico (AM) e ácido benzóico (AB) sobre células L929. Esses compostos foram testados em faixas de concentrações liberadas, em um período de 30 dias, por materiais reembasadores rígidos, previamente quantificadas em estudos anteriores. O efeito citotóxico foi verificado por meio dos testes de MTT e 3H-timidina, após as células terem sido expostas às substâncias testadas nas concentrações estabelecidas. A classificação da citotoxicidade foi baseada na viabilidade celular em relação ao controle (células expostas ao meio sem as substâncias testadas). A atividade de síntese de DNA foi inibida por todos os compostos. Os resultados do presente estudo demonstraram que o teste de 3H-timidina foi mais sensível que o teste de MTT e que os compostos avaliados mostraram diferentes níveis de citotoxicidade in vitro. A atividade da desidrogenase mitocondrial diminuiu nas células tratadas com os monômeros, o plastificante e o produto de degradação AM; porém, para o AB, a maioria das concentrações testadas não apresentou efeito citotóxico. / Abstract: The aim of this study was to evaluate the cytotoxic effect of the monomers 1,6 - hexanediol dimethacrylate (1,6 - HDMA) and isobutyl methacrylate (IBMA), the plasticizer di-n-butyl phthalate (DBP), and the degradation by-products methacrylic acid (MA) and benzoic acid (BA) on L929 cells. These compounds were tested in the range of concentrations released in 30 days from hard chairside reline resins that were quantified in previous investigations. Cytotoxic effects were assessed by using MTT and 3H - thymidine assays after the cells had been exposed to the test compounds at the given concentrations. Cytotoxicity was rated based on cell viability relative to controls (cells exposed to medium without test substances). The results presented in this study demonstrated that the 3H-thymidine assay was more sensitive than the MTT assay, and all compounds tested showed varying degrees of cytotoxic effect in vitro. DNA synthesis activity was inhibited by all compounds. Mitochondrial dehydrogenase activity decreased in cells treated with monomers, plasticizer and MA by-product, whereas no cytotoxic effect was observed on contact with BA at the majority of concentrations tested. / Orientador: Ana Lucia Machado / Coorientador: Iracilda Zeppone Carlos / Banca: Ana Cláudia Pavarina / Banca: Cláudia Lovato da Silva / Mestre
124

Estudo fitoquÃmico e avaliaÃÃo do potencial de inibiÃÃo da enzima acetilcolisnesterase de Simarouba versicolor (SIMAROUBACEAE) / Phytochemical study and evaluate the potential inhibition of the enzyme acetilcolisnesterase Simarouba versicolor (SIMAROUBACEAE)

Josà Ivan Ximenes de Carvalho 04 November 2008 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / O presente trabalho descreve o estudo quÃmico e farmacolÃgico da casca do caule da espÃcie Simarouba versicolor, pertencente à famÃlia Simaroubaceae. A espÃcie ocorre preferencialmente em Ãreas abertas de solos bem drenados, como cerrados e caatinga. Conhecida popularmente como âpau paraÃbaâ, âmata-cachorroâ ou âsimaruba do Brasilâ, a casca do seu caule possui propriedades inseticida e antihelmÃntica. Com o objetivo de estabelecer uma possÃvel relaÃÃo extrato atividade de inibiÃÃo da enzima acetilcolinesterase (AChE). Foi realizada uma triagem dos extratos das partes (folhas, talos, Galhos, Casca do caule e Cerne) da espÃcie Simarouba versicolor, atravÃs do ensaio de Ellman. O extrato etanÃlico da casca do caule apresentou elevada inibiÃÃo da AChE, desse extrato, as fraÃÃes clorofÃrmica e acetato de etila foram identificadas como sendo responsÃveis pela inibiÃÃo da enzima. A prospecÃÃo quÃmica da fraÃÃo clorofÃrmica resultou no isolamento de trÃs compostos, uma mistura de esterÃides β- sitosterol e estigmasterol, um quassinÃide, a 11-acetilamarolida e o alcalÃide 4,5- dimetÃxicantin-6-ona. Na fraÃÃo acetato de etila foi isolado o 3-β-O-β-D-glicopiranosil sistosterol. A determinaÃÃo estrutural desses compostos foi realizada atravÃs de anÃlise espectroscÃpica pelos mÃtodos de IV, EM, RMN1H e 13C-BB utilizando tÃcnicas uni e bidimensionais e por comparaÃÃo com dados descritos na literatura. Na anÃlise qualitativa de inibiÃÃo AChE os extratos e os constituintes isolados 11-acetilamarolida e 4,5-dimetÃxicantin-6-ona apresentaram bons resultados. Os extratos tambÃm apresentaram atividade citotÃxica em trÃs linhagens tumorais testados. / The present paper describes the chemical and pharmacological study of the stem bark of the species Simarouba versicolor, which belongs to the family Simaroubaceae. The species are found, mainly in open areas of well drained soils such as cerrado and caatinga. Known popularly as âpau Paraibaâ, âmata-cachorroâ or âBrazilian simarubaâ, the bark of its trunk has insecticidal and antihelminthic properties. It aims to establish a possible extract inhibition of enzyme activity of acetyl cholinesterase (AChE) Relationship. It was accomplished a triage of the parts extracts (leaves, stems, branches, stem bark and heartwood) of the species Simarouba Versicolor by the Ellman test. The ethanol extract of stem bark showed high inhibition of AChE, from this extract, the chloroform fraction and ethyl acetate were identified as being responsible for the inhibition of the enzyme. The chemical prospect of the chloroform fraction resulted in the isolation of three compounds, a mixture of steroid β-sitosterol and stigma sterol, a quassinoid, the 11-acetylamarolide and the alkaloid 4.5-dimetoxicantin-6-one. In the ethyl acetate fraction it was isolated the 3-β-O-β-D-glucopyranosyl sitosterol. The Structure determination of these compounds was performed by spectroscopic analysis through the methods of IR, MS, RMN1H and 13C-BB using uni and bidimensional techniques and by comparison with the data reported in the literature. In qualitative analysis of the AChE inhibition the extracts and isolated constituents 11- acetylamarolide and 4.5-dimetoxicantin-6-one showed good results. The extracts also showed cytotoxic activity in three tumor lines tested.
125

Efeitos genotóxicos e citotóxicos ex vivo do antifúngico fluconazol em leucócitos humanos

Silva, Gabriela de Souza da 27 April 2016 (has links)
Submitted by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2016-09-22T14:32:37Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Gabriela de Souza da Silva.pdf: 747981 bytes, checksum: c098f507cfc2f2c6e90b43f8f1a81fec (MD5) / Approved for entry into archive by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2016-09-22T14:32:51Z (GMT) No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Gabriela de Souza da Silva.pdf: 747981 bytes, checksum: c098f507cfc2f2c6e90b43f8f1a81fec (MD5) / Made available in DSpace on 2016-09-22T14:32:51Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Gabriela de Souza da Silva.pdf: 747981 bytes, checksum: c098f507cfc2f2c6e90b43f8f1a81fec (MD5) Previous issue date: 2016-04-27 / O fluconazol é um fármaco antifúngico de amplo espectro muito utilizado pela população. Contudo, são poucos os registros na literatura que imputem a segurança do uso do fluconazol e tampouco a dose mínima capaz de induzir lesões no material genético do paciente. Embora a Agência Nacional de Vigilância Sanitária (ANVISA) exija testes de genotoxicidade para admissão de novos medicamentos, os que têm seu registro expedido antes do ano de 2006 não trazem essa obrigatoriedade, incluindo-se aqui o fluconazol. Portanto, é de extrema importância estudos sobre a avaliação genotoxicológica de fármacos, principalmente os que são tão conhecidos e utilizados como o fluconazol. O presente estudo investigou os efeitos genotóxicos da cápsula e do princípio ativo do fluconazol através do teste cometa e do teste de proliferação celular e também os efeitos citotóxicos da cápsula e do princípio ativo do fluconazol através do teste de viabilidade celular. As concentrações testadas da cápsula e do princípio ativo do fluconazol foram 6, 12, 30, 60 e 120 μg/mL. Todos os ensaios foram realizados em triplicatas e o peróxido foi utilizado como controle positivo e tampão PBS 7,4 como controle negativo. Todas as concentrações testadas da cápsula do Fluconazol (6, 12, 30, 60 e 120 μg/mL) demonstraram ser capazes de interferir negativamente no processo de proliferação celular, diminuindo o número de células proliferadas em todas as concentrações testadas, quando comparadas ao controle negativo. Já no caso do princípio ativo do Fluconazol, apenas as três últimas concentrações (30, 60 e 120 μg/mL) interferiram negativamente no processo de proliferação celular. Na avaliação do índice de dano ao DNA (teste cometa), foi observado dano à estrutura de DNA nas concentrações 60 e 120 μg/mL da cápsula do Fluconazol. Já as concentrações testadas com o princípio ativo do Fluconazol não foi observado dano à estrutura de DNA. Foi verificado que a cápsula do Fluconazol possui atividade citotóxica sobre leucócitos humanos nas duas maiores concentrações testadas (60 e 120 μg/mL) de forma concentração dependente. Porém, o princípio ativo do Fluconazol não demonstrou ser citotóxico nas concentrações testadas (6 12, 30, 60 e 120 μg/mL). / Fluconazole is a broad-spectrum antifungal drug widely used by the population. However, there are few reports in the literature that imput the safety of the use of fluconazole and either the minimum dose capable of inducing lesions in the genetic material of the patient. Although the National Health Surveillance Agency (ANVISA) requires genotoxicity tests for admission of new medicines, which have their registration issued before 2006 do not bring this obligation, including here fluconazole. Therefore, it is extremely important genotoxicológica studies on the evaluation of drugs, especially such that are known and used as fluconazole. This study investigated the genotoxic effects of the capsule and the active principle of fluconazole by the comet test and the cell proliferation test and also the cytotoxic effects of the capsule and the active principle of fluconazole by cell viability test. The tested concentrations of the capsule and the active principle of fluconazole were 6, 12, 30, 60, and 120 mg/mL. All assays were performed in triplicate and peroxide was used as a positive control and PBS buffer as negative control 7.4. All tested concentrations of fluconazole capsule (6, 12, 30, 60 and 120 μg/mL) were capable of induce a negative interference in the cellular proliferation process, reducing the number of proliferating cells at all concentrations tested when compared to the negative control. In the case of the active ingredient, the fluconazole, only the last three concentrations (30, 60, and 120 μg/mL) were able to decrease the cellular proliferation process. In the assessment of DNA damage index (comet assay), there was observed damage of fluconazole capsule on the DNA structure at concentrations 60 and 120 μg/mL. On the other hand, the concentrations tested with the active ingredient of Fluconazole was not observed damage to the DNA structure. Fluconazole has been found that the capsule has a cytotoxic activity on human leukocytes at the two highest concentrations tested (60 and 120 μg/mL) as a concentration-dependent manner. However, the active ingredient of Fluconazole not induced any cytotoxic effect at the concentrations tested (6, 12, 30, 60, and 120 μg/mL).
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Síntese e atividade anti-Trichomonas vaginalis de chalconas

Trein, Marcia Rodrigues January 2017 (has links)
Tricomoníase é a doença sexualmente transmissível não-viral mais comum no mundo e pode gerar sérias consequências na saúde reprodutiva, câncer e transmissão e aquisição do HIV. Por esta razão, esta infecção resulta em um pesado fardo para os sistemas de saúde pública. O único tratamento aprovado para esta infecção, que consiste nos 5-nitromidazois metronidazol e tinidazol, apresenta efeitos adversos e há uma subestimada taxa de resistência da infecção, atualmente considerada uma doença negligenciada, a estes fármacos. Portanto, há uma necessidade urgente de novas alternativas terapêuticas para a tricomoníase. Chalconas são uma família de moléculas que apresenta várias aplicações biológicas, como atividade contra diversos patógenos, incluindo protozoários patogênicos. Este trabalho apresenta o potencial anti-Trichomonas vaginalis de derivados de chalcona sintetizados e seus efeitos sobre os trofozoítos. Os valores de IC50 dos compostos mais ativos variaram de 27,5 a 76,4 μM, e as moléculas 4’-hidroxichalcona e 3’-aminochalcona apresentaram os valores mais baixos (27,5 e 28,9 μM). Estes dois compostos foram citotóxicos contra a linhagem de células epiteliais vaginais HMVII, consequentemente apresentaram baixos Índices de Seletividade; contudo, ao se utilizar larvas de Galleria mellonella, como modelo de toxicidade in vivo, não foi observada diminuição da viabilidade após o tratamento. As moléculas também não provocaram hemólise em eritrócitos humanos em 1 e 24 horas. Os compostos não induziram significativa produção de espécies reativas de oxigênio (EROs) nos trofozoítos. Neutrófilos humanos apresentaram aumento na produção de EROs quando coincubados com trofozoítos tratados com os compostos. Os resultados indicam que as chalconas são uma família de moléculas com potencial atividade contra T. vaginalis. / Trichomoniasis is the most common non-viral sexually transmitted disease worldwide and can lead to serious consequences in reproductive health, cancer and HIV acquisition. For this reason, this infection results in a heavy burden for public health systems. Current approved treatment, which consists in 5-nitromidazole drugs, metronidazole and tinidazole, present adverse effects and there is underestimate drug resistance data on this parasitic infection, currently considered a neglected disease. Therefore, there is an urgent need for new alternatives for trichomoniasis treatment. Chalcones are a family of molecules that present various biological applications, such as activity against many pathogenic organisms including protozoan pathogens. This study presents the anti-Trichomonas vaginalis potential of synthetized chalcone derivatives and their effects on the trophozoites. IC50 values of the most active compounds ranged from 27.5 to 76.4 μM, and 4’-hydroxychalcone and 3’- aminochalcone presented the lowest values of IC50 (27.5 and 28.9 μM). These two compounds showed cytotoxicity against HMVII vaginal epithelial cells, thus presenting a low Selectivyty Index; however, when Galleria mellonella larvae were used as model for in vivo toxicity no significant decrease in viability after treatment was observed. The chalcones also did not induce hemolysis in human erythrocytes The compounds did not induce significant reactive oxygen species (ROS) production in the trophozoites. Human neutrophils have increased ROS production when exposed to treated trophozoites. Results indicate that chalcones are a family of molecules with potential activity against T. vaginalis.
127

Análise in vitro da citotoxicidade em osteoblastos de dispositivos poliméricos incorporados com antimicrobianos para uso local / In vitro analysis of cytotoxicity in osteoblasts of polymer devices incorporated with antimicrobials for local use

Lage, Thais Claudino 08 August 2017 (has links)
Os osteoblastos são células de origem mesenquimal envolvidas na formação óssea. Essas células podem sofrer alterações decorrentes de traumas, intervenções, e infecções. As infecções podem ser minimizadas a partir do uso de antimicrobianos. O poli(L-lactídeo) ou PLLA, é um polímero sintético que se destaca por sua biocompatibilidade e absorção, o qual pode ser utilizado como um liberador farmacológico local, como alternativa à terapêutica antimicrobiana sistêmica. Esse polímero também é empregado como matriz de suporte celular na engenharia de tecidos ósseos, por auxiliar na reparação e regeneração. A incorporação de partículas nesse polímero pode gerar reações adversas, portanto, devemos nos certificar que o dispositivo polimérico incorporado com antimicrobianos não seja citotóxico. Proposição: Analisar a estrutura e a citotoxidade em osteoblastos de dispositivos poliméricos de PLLA incorporados com antimicrobianos, sendo eles: Amoxicilina ou Azitromicina ou Clindamicina ou Metronidazol para uso local. Metodologia: Foram confeccionados 270 dispositivos poliméricos com 6mm de diâmetro composto de PLLA com a incorporação de antimicrobianos a 20%, Amoxicilina (AM) ou Azitromicina (AZ) ou Clindamicina (CL) ou Metronidazol (ME) sendo confeccionados através de dois métodos: eletrofiação (malhas) ou deposição (filmes). Posteriormente, foi realizado o teste de citotoxicidade direta MTT nesses dispositivos com a cultura de osteoblastos em 24, 48 e 72h de experimento. Para análise da estrutura do dispositivo, foram feitas análises macroscópicas através de fotografias digitais e microscópicas com Microscópio Eletrônico de Varredura (MEV). Resultados: A reação de citotoxidade mostrou que malhas e filmes incorporados à antimicrobianos são compatíveis com a cultura de osteoblastos, não apresentando citotoxicidade em nenhum momento do estudo (p<0.05). Na fotografia pudemos observar que os dispositivos apresentam coloração semelhante em relação às malhas e coloração diferenciada para filmes dependendo do tipo de antimicrobiano incorporado. No MEV, através da análise dos dispositivos pudemos notar que houve diferença no aspecto das superfícies dos filmes, sendo que os filmes de AM apresentaram aspecto irregular e poroso, enquanto AZ aparece liso com alguns grânulos, os de CL e ME possui superfícies ásperas e os de PLLA apresentaram superfície lisa. Quanto às malhas, notamos que todas as amostras apresentaram microfibras e poros que imitam a matriz extracelular, diferenciando-se apenas na espessura das fibras. Houve a presença de osteoblastos em todos os filmes confeccionados, mas os filmes de AM não induziram a proliferação, aparecendo apenas células isoladas. Enquanto nas malhas só foram observados osteoblastos em malhas de AM, ME e PLLA. Conclusão: Os dispositivos poliméricos confeccionados com PLLA incorporados com antimicrobianos podem ser usados na reparação e regeneração óssea uma vez que não apresentaram citotoxicidade em osteoblastos. / Osteoblasts are mesenquima originated cells, which are involved in the bone formation. These cells may suffer alterations due to traumas, interventions and infeccions. The infections can be minimized by the handling of antimicrobials. Poly (L-lactide) or PLLA is a synthetic polymer known for its biocompatibility and absorption, which can be used as a local pharmacological releaser, as an alternative to the systemic antimicrobial therapy. This polymer also can be frequently used as a supporting structure to cellular matrix in the bone tissue engineering as it can be used for support in repair and regeneration. The particle incorporation in this polymer can create side effects, therefore, we need to certificate that the polymeric device incorporated with antimicrobials are not cytotoxic. Proposition: Analyse the structure and cytotoxicity in osteoblasts of PLLA polymeric devices associated with antimicrobials, being them: Amoxicillin, Azithromycin, Clindamycin and Metronidazole. Methods: For this study 270 polymerical devices were manufactured with 6mm diameter of PLLA with a 20% antimicrobials incorporation of Amoxicillin (AM), Azithromycin (AZ), Clindamycin (CL) and Metronidazole (ME) that have been produced through two methods: eletrospinning (mesh) or casting (film). Afterwards a MTT cytotoxicity test was made over the periods of 24, 48 and 72 hours of experiment. To make a structural analysis of the device a macroscopic analysis was performed through photographs and microscopic imaging with scanning electron microscope (SEM). Results: The cytotoxicity reaction exhibited that meshes and films incorporated with antimicrobials are comparable with the osteoblasts culture, indicating that there was no cytotoxicity in any moment (p < 0.05). In the phothograph we could observe that the devices showed a similar coloration among the meshes and different coloration for the films depending on the incorporated antimicrobial. The SEM analysis displayed a difference in the surface appearance of the films. The AM films displayed an irregular and porous appearance, meanwhile, AZ looked smooth with few grains, the CL and ME have rough surfaces and PLLA presents smooth surfaces. As for the meshes, we noticed that all the samples had microfibers and pores that mimic the extracellular matrix, differing only in the thickness of the fibers. Osteoblasts were present in all films but AM did not induce proliferation, with only isolated cells emerging. In meshes osteoblasts were only found in AM, ME and PLLA. Conclusion: Polymeric devices made with PLLA incorporated with antimicrobials can be used in bone repair and regeneration given that they did not offer cytotoxicity for osteoblasts.
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Estudo de novos compostos guanidínicos inibidores da enzima desoxi-hipusina sintase (DHPS) como agentes antiproliferativos e antifúngicos /

Barrios Eguiluz, Alexandra Daniela. January 2018 (has links)
Orientador: Cleslei Fernando Zanelli / Coorientadora: Tatiana Maria de Souza Moreira / Banca: Alexandra Ivo de Mendeiros / Banca: Geisiany Maria de Queiroz-Fernandes / Resumo: O fator de tradução de eucariotos eIF5A é descrito como a única proteína que apresenta o aminoácido hipusina, o qual é gerado por uma modificação pós-traducional essencial para a proliferação celular em todos os eucariotos estudados até o momento, sendo que a enzima desoxi-hipusina sintase (DHPS) é responsável pela primeira etapa da formação desse aminoácido em eIF5A. Portanto, a inibição de DHPS também impede a modificação de eIF5A, tornando esta proteína não funcional, o que pode ter aplicação no tratamento dos tipos de câncer em que o fator está envolvido. Embora N1-guanil-1,7-diamino-heptano (GC7) seja potente inibidor da enzima DHPS, foram observados outros efeitos na célula devido à atuação do composto em alvos não específicos. Desta forma, o presente trabalho tem como objetivo a busca por novos inibidores de DHPS, com baixa citotoxicidade e que reduzam a proliferação celular ou que inibam o crescimento de micro-organismos eucarióticos patogênicos, como algumas espécies de fungos. Primeiramente, foi avaliada a citotoxicidade de diferentes compostos com núcleo guanidínico frente a macrófagos murinos. Entre os compostos testados, aqueles que apresentaram menor citotoxicidade foram o composto GC7 e os compostos de núcleo guanidínico com um grupo fenil substituído em para por uma metila e outro por um flúor. A partir deste resultado, os compostos foram submetidos à avaliação de sua atividade antiproliferativa frente às mesmas células. GC7 promoveu inibição da proliferação c... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Eukaryotic translation factor eIF5A is described as the only protein that presents the amino acid hypusine that is generated by a post-translational modification, which is essential for cell proliferation in all the eukaryotes studied to date. The enzyme deoxyhypusine synthase (DHPS) is responsible for the first stage of formation of this amino acid in eIF5A. Therefore, the inhibition of DHPS also prevents the modification of the eIF5A, making this protein non-functional, which may have application in the treatment of cancer kinds in which this factor is involved. Although N1-guanyl-1,7-diaminoheptane (GC7) is a strong inhibitor of the DHPS enzyme, other effects on the cell were observed due to the acting of the compound on non-specific targets. Thus, the present work aims to search for new DHPS inhibitors, with low cytotoxicity and able to reduce cell proliferation or inhibit the growth of pathogenic eukaryotic microorganisms such as some fungal species. Firstly, the cytotoxicity of different compounds with guanidinic nucleus against murine macrophages was evaluated. Among the compounds tested, those that showed the lowest cytotoxicity were the GC7 compound and the guanidine core compounds with a phenyl group substituted in para for one methyl and another with fluorine. From these data, the antiproliferative activity of the compounds towards the same cells was evaluated. GC7 promoted inhibition of proliferation as already described in the literature, but the compounds tested... (Complete abstract click electronic access below) / Mestre
129

Mobilization of Iron Enhances the Iron-Dependent Biochemical Reactivity of Asbestos in Vitro and Contributes to the Cytotoxicity of Asbestos in Cultured Cells

Lund, Loren Glen 01 May 1992 (has links)
Asbestos related research began approximately 60 years ago, yet, the mechanism(s) by which asbestos exerts its biological effects is not well understood. The hypothesis upon which this dissertation is based is that mobilization of iron from asbestos enhances the iron-dependent biochemical reactivity of asbestos in vitro and contributes to asbestos-dependent cytotoxicity. The specific aims for this hypothesis were, 1) to determine whether iron was responsible for the biochemical reactivity of asbestos in vitro and asbestos-induced cytotoxicity in cultured cells, and 2) to determine whether mobilization of iron from asbestos enhanced the reactions catalyzed by asbestos in vitro and contributes to asbestos-induced cytotoxicity. It was shown that a chelator (e.g., citrate) had to be present to mobilize iron from asbestos in vitro at pH 7.5. Factors that affected iron mobilization from asbestos (e.g., chelator, pH, or surface area) were investigated. Iron on crocidolite reacted with reducing agents and o2, catalyzed the formation of hydroxyl radical, and induced the formation of DNA single-strand breaks in vitro. However, mobilization of iron from crocidolite by a chelator greatly enhanced crocidolite-dependent o2 consumption, hydroxyl radical formation, and DNA damage in vitro. Crocidolite was more cytotoxic, as measured by cloning efficiency, to cultured Syrian hamster embryo cells than crocidolite that had been pretreated to reduce the amount of iron associated with the fiber, suggesting that iron was responsible for the cytotoxicity. Crocidolite-dependent transformation of these cells was not detected. Crocidolite-dependent cytotoxicity to the human lung carcinoma cell line, A549, was directly dependent upon dose. Intracellular mobilization of iron (55 Fe) from crocidolite was determined using neutron-activated crocidolite and A549 cells. A time- and dose-dependent increase in the amount of 55 Fe mobilized intracellularly from crocidolite into a soluble, 10,000 x g supernatant fraction of lysed cells was observed for cultured cells treated up to 72 h. All of the results presented here support the hypothesis that iron and/or iron mobilization from asbestos may contribute to the some of the biological effects of asbestos in vivo.
130

The effect of cadmium on food allergy

Boupha, Prasongsidh C., University of Western Sydney, Hawkesbury, Faculty of Science and Technology, School of Food Science January 1992 (has links)
Assessement of effects of cadium chloride exposure on the anaphylaxis reaction to food was done on six week old Swiss and BALB/c female mice. The animals were exposed to cadium as cadium chloride for either three days or six weeks. Intra-peritonal dose of cadium chloride was injected once a day, five days per week for three successive weeks. The animals were then sensitised to cow's milk by force-feeding with cow's milk for three consecutive days. Oral exposure of mice to a high dose of cadium resulted in cytotoxicity of liver and kidney cells. Retardation in growth rate and haematology change were detected. Proliferative response to the T-cell epitope from the circumsporozoite protein of plasmodium falsiparum was decreased in cultures of lymph node cells from cadium chronically treated mice and sensitised with the same peptide. In contrast, an increase of cell proliferation was observed when cow's milk was used instead. Significant increase in Immunoglobulin E level and Anaphylactic reaction dependent on the quantity of cadium exposed were recorded. No protective effect of ascorbic acid or zinc acetate on cadium alteration of immune response was observed / Master of Science (Hons) (Food Science)

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