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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.
41

Atividade antioxidante in vitro de extrato de folhas de oliveira (Olea europaea L.) e seu efeito protetor sobre danos oxidativos em eritrócitos humanos / In vitro antioxidant activity of olive leaf extract (Olea europaea L.) and its protective effect against oxidative damage in human erythrocytes

Lins, Patricia Goldschmidt 15 December 2015 (has links)
O objetivo do presente estudo foi avaliar a atividade antioxidante de extrato de folhas de oliveira (EFO) (Olea europaea L.) por diferentes metodologias analíticas in vitro e in situ, para verificação de efeito em sistemas biológicos. O extrato foi obtido a partir de folhas secas de oliveira, previamente micronizadas, em metanol/água (80/20%) na proporção 1:20 (m/v), após remoção de compostos solúveis em n-hexano. Após liofilização, no EFO foi avaliado o poder redutor por Folin-Ciocalteau, conteúdo de flavonoides totais, teor de oleuropeina, poder de redução do íon férrico (FRAP) e atividade antioxidante sobre DPPHo, ABTSo+, ânion superóxido (O2o-), ácido hipocloroso (HOCl) e óxido nítrico (NOo). O extrato foi também avaliado quanto ao efeito protetor sobre danos oxidativos em eritrócitos humanos. O ácido ascórbico foi utilizado como referência. O experimento foi repetido seis vezes (n = 6) e os ensaios realizados em duplicata. O poder redutor do extrato e o conteúdo de flavonoides totais e oleuropeína foram 131,7 ± 9,4 mg equivalente de ácido gálico/g extrato seco (ms), 19,4 ± 1,3 mg equivalente de quercetina/g ms e 25,5 ± 5,2 mg oleuropeína/g ms, respectivamente. O ensaio de FRAP apresentou 281,8 ± 22,8 mg equivalente de trolox/g ms. O EFO foi efetivo na inibição dos radicais DPPHo e ABTSo+, dependente da concentração de extrato, com valores de IC50 de 13,8 ± 0,8 e 16,1 ± 1,2 µg/mL, respectivamente. Com relação à atividade antioxidante sobre espécies reativas de importância biológica, o EFO apresentou forte capacidade de inibição de O2o- (IC50 = 52,6 ± 2,1 µg/mL) e NOo (IC50 = 48,4 ± 6,8 µg/mL), quando comparado ao ácido ascórbico. Porém, a inibição de HOCl não foi tão eficiente (IC50 = 714,1 ± 31,4 µg/mL). O EFO inibiu a hemólise induzida em eritrócitos de maneira dependente da concentração (IC50 = 7,8 ± 1,1 µg/mL), assim como a peroxidação lipídica e a formação de meta-hemoglobina, com valores de IC50 de 38,0 ± 11,7 e 186,3 ± 29,7 µg/mL, respectivamente. Os resultados obtidos neste estudo sugerem que extrato de folhas de oliveira possui efetiva atividade antioxidante em sistemas biológicos, pelo efeito sequestrador de determinadas espécies reativas que participam dos processos bioquímicos, e pela prevenção de danos oxidativos em eritrócitos humanos. Portanto, sua ingestão pode estar relacionada com a prevenção de estresse oxidativo in vivo, com consequentes benefícios à saúde. / The aim of this study was to evaluate the antioxidant activity of olive leaf extract (OLE) (Olea europaea L.) by different in vitro and in situ analytical methodologies for determination of its effect in biological systems. The extract was obtained from dried olive leaves, previously micronized, in methanol/water (80/20%) in ratio 1:20 (w/v), after removal of n-hexane soluble compounds. After lyophilization, OLE was analyzed for reducing power by Folin-Ciocalteau, total flavonoid content, oleuropein content, ferric reducing antioxidant power (FRAP) and antioxidant activity against DPPHo, ABTSo+, superoxide anion (O2o-), hypochlorous acid (HOCl), and nitric oxide (NOo). The extract was also analyzed against oxidative damage in human erythrocytes. Ascorbic acid was used as reference. The experiment was repeated six times (n = 6) and the assays were performed in duplicate. The reducing power and total flavonoid and oleuropein contents of extract were 131.7 ± 9.4 mg galic acid equivalent/g dry extract (dw), 19.4 ± 1.3 mg quercetin equivalent/g dw, and 25.5 ± 5.2 mg oleuropein/g dw, respectively. The FRAP assay was 281.8 ± 22.8 mg trolox equivalent/g dw. The OLE was effective in inhibition of DPPHo and ABTSo+ radicals, in a concentration dependent manner, with IC50 values of 13.8 ± 0.8 and 16.1 ± 1.2 µg/mL, respectively. In relation to the antioxidant activity against reactive species of biological importance, the OLE showed high ability to inhibit O2o- (IC50 = 52.6 ± 2.1 µg/mL) and NOo (IC50 = 48.4 ± 6.8 µg/mL), when compared to ascorbic acid. However, inhibition of HOCl was not as efficient (IC50 = 714.1 ± 31.4 µg/mL). The OLE inhibited induced erythrocyte hemolysis in a concentration dependent manner (IC50 = 7.8 ± 1.1 µg/mL) as well as lipid peroxidation and the formation of methemoglobin, with IC50 values of 38.0 ± 11.7 and 186.3 ± 29.7 µg/mL, respectively. The results suggest that olive leaf extract has effective antioxidant activity in biological systems, based on its scavenging effect of certain reactive species that participate in biochemical processes, and the prevention of oxidative damage in human erythrocytes. So, the intake of olive leaf extract may be related to the prevention of in vivo oxidative stress, with health benefits.
42

Estudo dos mecanismos moleculares envolvidos na ação tóxica das esfingomielinases D do veneno de aranhas Loxosceles e de sua modulação pelo uso de inibidores. / Study of the molecular mechanisms involved in the toxic action of sphingomyelinases D from Loxosceles spider venom and its modulation by the use of inhibitors.

Lopes, Priscila Hess 17 May 2013 (has links)
O veneno de aranhas Loxosceles consiste em uma mistura de proteínas com atividade enzimática ou tóxica, incluindo as esfingomielinases D (SMases D), consideradas como os principais componentes tóxicos do veneno, responsáveis pelo estabelecimento dos efeitos locais e sistêmicos. O presente estudo teve como objetivo avaliar o potencial inibitório de moléculas selecionadas por docking molecular sobre as propriedades tóxicas das SMases D. Os dados obtidos mostram que as moléculas selecionadas foram capazes de inibir a atividade hidrolítica da toxina, o mecanismo de hemólise dependente de complemento e eficazes no controle da progressão das lesões dermonecróticas em coelhos. Estes resultados indicam que inibidores específicos para as SMases D são capazes de controlar as reações locais e sistêmicas induzidas pelo veneno de Loxosceles. Estas são ferramentas promissoras para estudos de estrutura/função e para o desenvolvimento de novas intervenções terapêuticas para o loxoscelismo. / Loxosceles spider venom is a mixture of proteins with enzymatic or toxic activity, including sphingomyelinases D (SMases D), considered as the main toxic components of the venom responsible for the establishment of local and systemic effects. This study aimed to evaluate the inhibitory potential of molecules selected by molecular docking on the toxic properties of SMases D. The results demonstrated that selected molecules were able to inhibit the hydrolytic activity of the toxin, the mechanism of complement-dependent hemolysis and effective in reducing the progression of the dermonecrotic lesion in rabbits. These results indicate that specific inhibitors for SMases D are capable of controlling local and systemic reactions induced by Loxosceles venom. These are promising tools for function/structure studies and for developing new therapeutic interventions for the loxoscelism.
43

Mechanisms of virulence associated with thermolabile hemolysin (TLH) from Vibrio alginolyticus on erythrocytes of silver sea bream, Sparus sarba.

January 2011 (has links)
Wong, Sze Ki. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 87-106). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstract --- p.ii / Abstract in Chinese --- p.iv / Table of contents --- p.V / List of figures --- p.ix / List of abbreviations --- p.X / Chapter Chapter 1. --- General introduction --- p.1 / Chapter Chapter 2. --- Literature review --- p.6 / Chapter 2.1. --- Pathogenic mechanisms of Vibrio species in fish --- p.7 / Chapter 2.1.1. --- Introduction --- p.7 / Chapter 2.1.2. --- Adhesion --- p.7 / Chapter 2.1.3. --- Invasion --- p.8 / Chapter 2.1.4. --- Proliferation --- p.9 / Chapter 2.2. --- Vibrio virulence factors --- p.12 / Chapter 2.2.1. --- Introduction --- p.12 / Chapter 2.2.2. --- Hemolysin --- p.12 / Chapter 2.2.3. --- Protease --- p.14 / Chapter 2.2.4. --- Siderophore --- p.15 / Chapter 2.2.5. --- Lipopolysaccharide --- p.15 / Chapter 2.3. --- General apoptotic pathways --- p.17 / Chapter 2.3.1. --- Introduction --- p.17 / Chapter 2.3.2. --- Extrinsic apoptotic pathway --- p.17 / Chapter 2.3.2.1. --- Death receptor signaling apoptosis --- p.17 / Chapter 2.3.2.1.1. --- Fas signaling pathway --- p.18 / Chapter 2.3.2.1.2. --- TNF-R1 signaling pathway --- p.19 / Chapter 2.3.2.1.3. --- TRAIL receptors signaling pathway --- p.20 / Chapter 2.3.2.2. --- Growth factor receptor signaling apoptosis --- p.21 / Chapter 2.3.3. --- Intrinsic apoptotic pathway --- p.21 / Chapter 2.3.3.1. --- Mitochondrial apoptotic pathway --- p.21 / Chapter 2.3.3.1.1. --- Cyto c --- p.22 / Chapter 2.3.3.1.2. --- Smac/DIABLO --- p.22 / Chapter 2.3.3.1.3. --- Omi/HtrA2 --- p.22 / Chapter 2.3.3.1.4. --- AIF and endo G --- p.23 / Chapter 2.3.3.1.5. --- Bcl-2 family --- p.23 / Chapter 2.3.3.1.6. --- Mitochondrial membrane permeabilization (MMP) --- p.23 / Chapter 2.3.3.2. --- p53-regulated apoptotic pathway --- p.24 / Chapter 2.3.3.3. --- Endoplasmic reticulum (ER) stress-induced apoptotic pathway --- p.25 / Chapter 2.4. --- Membrane vesiculation in erythrocytes --- p.26 / Chapter 2.4.1. --- Introduction --- p.26 / Chapter 2.4.2. --- Induction of vesiculation --- p.26 / Chapter 2.4.3. --- Contents of vesicles --- p.28 / Chapter 2.4.4. --- Mechanisms involved during vesiculation --- p.29 / Chapter 2.4.5. --- Correlation between apoptosis and membrane vesiculation in erythrocytes --- p.31 / Chapter 2.4.6. --- Reasons for vesiculation --- p.31 / Chapter Chapter 3. --- "Induction of apoptosis by Vibrio alginolyticus thermolabile hemolysin (TLH) in blood cells of silver sea bream, Sparus sarba" --- p.33 / Chapter 3.1. --- Abstract --- p.34 / Chapter 3.2. --- Introduction --- p.34 / Chapter 3.3. --- Materials and methods --- p.36 / Chapter 3.3.1. --- Experimental fish --- p.36 / Chapter 3.3.2. --- Whole blood preparation --- p.37 / Chapter 3.3.3. --- Preparation of V. alginolyticus TLH --- p.37 / Chapter 3.3.4. --- "Caspase-3, -8, -9/6 fluorescent assay" --- p.38 / Chapter 3.3.5. --- TUNEL assay --- p.39 / Chapter 3.3.6. --- Apoptotic DNA ladder assay --- p.40 / Chapter 3.3.7. --- Statistical analysis --- p.41 / Chapter 3.4. --- Results --- p.42 / Chapter 3.4.1. --- "Increase of caspase-3, -8, -9/6 activities" --- p.42 / Chapter 3.4.2. --- Detection of DNA fragmentation by TUNEL assay --- p.44 / Chapter 3.4.3. --- Detection of DNA fragmentation by apoptotic DNA ladder assay --- p.44 / Chapter 3.5. --- Discussion --- p.46 / Chapter Chapter 4. --- "Occurrence of membrane vesiculation, apoptosis and post-apoptotic necrosis after exposure to Vibrio alginolyticus thermolabile hemolysin (TLH) in erythrocytes of silver sea bream, Sparus sarba" --- p.51 / Chapter 4.1. --- Abstract --- p.52 / Chapter 4.2. --- Introduction --- p.52 / Chapter 4.3. --- Materials and methods --- p.54 / Chapter 4.3.1. --- Experimental fish --- p.54 / Chapter 4.3.2. --- Whole blood preparation --- p.54 / Chapter 4.3.3. --- Preparation of V. alginolyticus TLH --- p.55 / Chapter 4.3.4. --- Light microscopy --- p.55 / Chapter 4.3.5. --- Transmission electron microscopy (TEM) --- p.56 / Chapter 4.3.6. --- Measurement of membrane vesiculation - acetylcholinesterase (AChE) assay --- p.56 / Chapter 4.3.7. --- Measurement of necrosis - hemoglobin colorimetric assay --- p.57 / Chapter 4.3.8. --- Apoptotic DNA ladder assay --- p.58 / Chapter 4.3.9. --- Flow cytometry --- p.59 / Chapter 4.3.10. --- Statistical analysis --- p.59 / Chapter 4.4. --- Results --- p.60 / Chapter 4.4.1. --- Ultrastructural changes in red blood cells after exposure to TLH --- p.60 / Chapter 4.4.2. --- Changes of cell population in size and granularity after exposure of TLH --- p.67 / Chapter 4.4.3. --- Effect of TLH dosage on necrosis and DNA fragmentation --- p.72 / Chapter 4.4.4. --- "Occurrence of membrane vesiculation, necrosis and DNA fragmentation in cells exposed to TLH" --- p.72 / Chapter 4.5. --- Discussion --- p.76 / Chapter Chapter 5. --- General conclusions --- p.82 / References --- p.87
44

Estudos com Syzygium cumini (L.) Skeel: Caracterização da matéria-prima, perfil fitoquímico, citotoxidade e atividade antimicrobiana sobre microorganismos associados ao biofilme dental

Furtado, Nathália Alexandra de Oliveira Cartaxo 22 April 2014 (has links)
Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2016-03-17T14:03:25Z No. of bitstreams: 1 PDF - Nathália Alexandra de Oliveira Cartaxo.pdf: 1587194 bytes, checksum: 60766da222502f8476607dd32500b432 (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2016-07-22T13:35:33Z (GMT) No. of bitstreams: 1 PDF - Nathália Alexandra de Oliveira Cartaxo.pdf: 1587194 bytes, checksum: 60766da222502f8476607dd32500b432 (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2016-07-22T13:35:42Z (GMT) No. of bitstreams: 1 PDF - Nathália Alexandra de Oliveira Cartaxo.pdf: 1587194 bytes, checksum: 60766da222502f8476607dd32500b432 (MD5) / Made available in DSpace on 2016-07-22T13:35:42Z (GMT). No. of bitstreams: 1 PDF - Nathália Alexandra de Oliveira Cartaxo.pdf: 1587194 bytes, checksum: 60766da222502f8476607dd32500b432 (MD5) Previous issue date: 2014-04-22 / The aim of this study was to characterize the vegetable raw material, as well as analyze the phytochemical profile, cytotoxicity and antimicrobial activity of the leaf extract of Syzygium cumini (L.) Skeel on microorganisms associated with dental biofilm. The characterization was performed by the determination of physicochemical properties: particle size, apparent uncompressed density, pH, ash content and loss on drying powder of Syzygium cumini plant drug L. Skeels and application of analytical techniques (electron microscopy scanning, thermal analysis - Differential scanning calorimetry (DSC) and Termogravimetry (TG), X-ray diffraction and infrared spectroscopy) to characterize and implement a quality control of the lyophilized extract of leaves jambolan, which has antimicrobial property. In addition, was determined the antimicrobial activity of the extract of Syzygium cumini (L.) Skeel on microorganisms associated with dental plaque, as well as the phytochemical profile and cytotoxicity. The antimicrobial activity was performed by microdilution broth. Was determined Minimum Inhibitory Concentration (MIC), Minimum Bactericidal Concentration (MBC) and Minimum Fungicidal Concentration (MFC) of the lyophilized extract against Streptococcus mutans (ATCC 25175), Streptococcus parasanguis (ATCC 903), Streptococcus oralis (ATCC 10557), Streptococcus salivarius (ATCC 7073) and Candida albicans (ATCC 10231). Phytochemical analysis was performed by spectroscopy in the visible region and was quantified polyphenols, flavonoids, condensed tannins and total saponins. Cytotoxicity was measured by the hemolysis method. The results demonstrate that particle size of the powder leaves of S. cumini is thick, the pH is acidic and has good density. The ash content and loss on drying were within the parameters recommended by the Pharmacopoeia. The analysis of the extract showed a typical feature of plant extracts, in other words, the particles showed amorphous property. Furthermore, such particles could be observed in the microscopy irregularly shaped, forming agglomerates of different sizes and morphology. In thermal characterization of the extract, five events of decomposition, presented by TG and DSC curves occurred; this had endothermic characteristic. The IR spectrum suggested various functional groups of compounds present in the lyophilized extract in different absorption bands.For Streptococcus, S. cumini was only active against S. mutans and S. oralis (MIC 1mg/mL).The extract showed potential antifungal activity against C. albicans, demonstrating strong fungistatic and fungicidal activity. The quantification of secondary metabolites obtained satisfactory results, especially with high concentrations of total polyphenols and saponins. The extract showed low cytotoxicity. Therefore, the profile of leaves of S. cumini was drawn, showing up in general good physico-chemical, chemical and thermal characteristics. S. cumini has a good antimicrobial potential, with acceptable levels of phytochemicals and compounds with low cytotoxicity and is therefore recommended for use with safety and efficacy in the prevention and treatment of diseases resulting biofilm. / O objetivo desse estudo foi caracterizar a matéria prima vegetal, bem como analisar o perfil fitoquímico, a citotoxicidade e a atividade antimicrobiana do extrato de folhas de Syzygium cumini (L.) Skeel sobre microrganismos associados ao biofilme dental. A caracterização foi realizada por meio da determinação de propriedades físicoquímicas: granulometria, densidade aparente não compactada, pH, teor de cinzas e teor de água do pó da droga vegetal de Syzygium cumini L. Skeels e aplicação de técnicas analíticas (microscopia eletrônica de varredura, análise térmica– Calorimetria Exploratória Diferencial (DSC) e Termogravimetria (TG), difração de raio-X e espectroscopia de infravermelho - IV) para caracterizar e verificar a autenticidade do extrato liofilizado de folhas de jambolão, que possui propriedade antimicrobiana. Além disso, determinou-se a atividade antimicrobiana do extrato de Syzygium cumini(L.) Skeel sobre microrganismos associados ao biofilme dental, assim como o perfil fitoquímico e a citotoxicidade. A atividade antimicrobiana foi realizada através da técnica de microdiluição em caldo. Determinou-se a Concentração Inibitória Mínima (CIM), Concentração Bactericida Mínima (CBM) e Concentração Fungicida Mínima (CFM) do extrato liofilizado frente a Streptococcus mutans (ATCC 25175), Streptococcus parasanguis (ATCC 903), Streptococcus oralis (ATCC 10557), Streptococcus salivarius (ATCC 7073) e Candida albicans (ATCC 10231). A análise fitoquímica foi realizada por espectroscopia na região visível e quantificou-se polifenóis, flavonóides, taninos condensados e saponinas totais. A citotoxicidade foi realizada pelo método de hemólise. Os resultados de granulometria demonstram que o pó de folhas de S. cumini é grosso, apresenta boa densidade e o pH é ácido. O teor de cinzas e o teor de água estiveram dentro dos parâmetros preconizados pela Farmacopeia. A análise do extrato mostrou uma característica típica de extratos vegetais, ou seja, as partículas apresentaram propriedade amorfa. Além disso, essas partículas puderam ser observadas nas microscopias com formatos irregulares, formando aglomerados de diferentes tamanhos e morfologia. Na caracterização térmica do extrato, ocorreram cinco eventos térmicos, apresentados por curvas de DSC e TG, de caráter endotérmico. O espectro de IV sugeriu diversos grupos funcionais dos compostos presentes no extrato liofilizado, em distintas bandas de absorção. Para Streptococcus, Syzygium cumini só foi ativo frente a Streptococcus mutans e aStreptococcus oralis(CIM de 1mg/mL). O extrato apresentou grande potencial antifúngico sobre C. albicans, demonstrando forte atividade fungistática e fungicida. A quantificação de metabólitos secundários obteve resultados satisfatórios, especialmente com altas concentrações de saponinas e polifenóis totais. O extrato apresentou baixa citotoxicidade. Portanto, o perfil de folhas de S. cumini foi traçado, mostrando-se no geral com boas características físico-químicas, químicas e térmicas. S. cumini é uma planta com bom potencial antimicrobiano, com aceitáveis concentrações de compostos fitoquímicos e com baixa citotoxicidade, sendo por isso recomendada a sua utilização com segurança e eficácia na prevenção e tratamento de doenças decorrentes do biofilme dental.
45

A biochemical study of defense proteins: hemagglutinin, hemolysin and antifungal protein.

January 2007 (has links)
Leung, Ho Wai. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 136-146). / Abstracts in English and Chinese. / THESIS COMMITTEE --- p.II / ACKNOWLEDGEMENT --- p.III / ABSTRACT --- p.IV / CHINESE ABSTRACT --- p.VI / TABLE OF CONTENT --- p.VII / OVERVIEW OF THIS PROJECT --- p.1 / Chapter SECTION 1: --- Purification and Characterization of hemagglutinins from French bean and mottled kidney bean / Chapter Chapter 1 --- INTRODUCTION / Chapter 1.1 --- General Introduction --- p.2 / Chapter 1.2 --- Physiological functions of plant lectins --- p.6 / Chapter 1.3 --- Physiological functions of animal lectins --- p.9 / Chapter 1.4 --- Biological functions of lectins --- p.12 / Chapter 1.5 --- Clinical and research applications of lectins --- p.16 / Chapter 1.6 --- Legume lectins --- p.17 / Chapter 1.7 --- Isolation and purification of lectins --- p.19 / Chapter 1.8 --- Objectives of the present study --- p.21 / Chapter Chapter 2 --- MATERIALS AND METHODS / Chapter 2.1 --- Chemicals --- p.22 / Chapter 2.2 --- Assay of hemagglutinating activity --- p.24 / Chapter 2.3 --- Purification protocol --- p.26 / Chapter 2.4 --- Assay of saccharide inhibition of hemagglutination --- p.28 / Chapter 2.5 --- Assay of pH stability --- p.28 / Chapter 2.6 --- Molecular mass determination and N-terminal sequence determination --- p.28 / Chapter 2.7 --- Assay of mitogenic activity --- p.29 / Chapter 2.8 --- Assay of antiproliferative activity --- p.30 / Chapter 2.9 --- Assay for antifungal activity --- p.30 / Chapter 2.10 --- Assay of HIV-1 reverse transcriptase inhibitory activity --- p.31 / Chapter 2.11 --- Assay of stability towards trypsin and chymotrypsin --- p.31 / Chapter 2.12 --- Assay of nitric oxide production --- p.32 / Chapter 2.13 --- Assay ofHIV-1 integrase --- p.32 / Chapter Chapter 3 --- EXPERIMENTAL RESULTS / Chapter 3.1 --- Purification scheme --- p.35 / Chapter 3.2 --- Size determination and N-terminal sequencing --- p.36 / Chapter 3.3 --- Temperature stability assay --- p.37 / Chapter 3.4 --- pH stability assay --- p.37 / Chapter 3.5 --- Saccharides inhibition of hemagglutination --- p.37 / Chapter 3.6 --- Stability towards Trypsin and Chymotrypsin --- p.38 / Chapter 3.7 --- Anti-proliferative activity --- p.38 / Chapter 3.8 --- HTV-1 reverse transcriptase inhibition --- p.39 / Chapter 3.9 --- Mitogenic activity --- p.39 / Chapter 3.10 --- Nitric oxide production --- p.39 / Chapter 3.11 --- HIV-1 integrase --- p.39 / Chapter 3.12 --- Defensin --- p.40 / Chapter Chapter 4 --- DISCUSSION / Chapter 4.1 --- Purification scheme --- p.68 / Chapter 4.2 --- Sequence comparison --- p.69 / Chapter 4.3 --- Physical Stability of the hemagglutinins --- p.70 / Chapter 4.4 --- Protease Stability --- p.71 / Chapter 4.5 --- Sugar Specificity Assay --- p.72 / Chapter 4.6 --- Anti-proliferative Aactivity toward Cancer Cells --- p.73 / Chapter 4.7 --- HTV-1 reverse trancriptase and H̐ơþV integrase inhibition --- p.74 / Chapter 4.8 --- Mitogenic activity --- p.75 / Chapter 4.9 --- Antifungal protein --- p.76 / Chapter Chapter 5 --- CONCLUSION --- p.78 / Chapter SECTION 2: --- Purification and Characterization of flammulolysin from mushroom Flαmmulinα velutipes / Chapter Chapter 1 --- INTRODUCTION / Chapter 1.1 --- General Introduction --- p.79 / Chapter 1.2 --- Mechanisms of hemolysis --- p.80 / Chapter 1.3 --- Biological role of hemolysins --- p.80 / Chapter 1.4 --- Mushroom hemolysin --- p.82 / Chapter 1.5 --- Applications of hemolysins --- p.83 / Chapter 1.6 --- Objectives of the present study --- p.83 / Chapter Chapter 2 --- MATERIALS AND METHODS --- p.84 / Chapter Chapter 3 --- EXPERIMENTAL RESULTS / Chapter 3.1 --- Purification and sequence determination --- p.90 / Chapter 3.2 --- Effect of sugars and salts on hemolysin --- p.90 / Chapter 3.3 --- Effect of Temperature and pH on hemolysin --- p.91 / Chapter 3.4 --- Effect of Proteases on hemolysin --- p.91 / Chapter 3.5 --- Effect of osmotic protection on hemolysin --- p.91 / Chapter 3.6 --- Effect of hemolysin on tumor cells --- p.91 / Chapter 3.7 --- Effect of hemolysin on spleen cells --- p.92 / Chapter 3.8 --- Effect of hemolysin on bacterial growth --- p.92 / Chapter 3.9 --- Effect of hemolysin on fungal growth --- p.92 / Chapter Chapter 4 --- DISCUSSION / Chapter 4.1 --- Purification and sequence comparison of hemolysin --- p.103 / Chapter 4.2 --- Sugar and Salts inhibition --- p.104 / Chapter 4.3 --- Temperature stability --- p.105 / Chapter 4.4 --- pH stability --- p.106 / Chapter 4.5 --- Protease stability --- p.106 / Chapter 4.6 --- Osmotic Protection --- p.106 / Chapter 4.7 --- Anti-tumour activity of the hemolysin --- p.107 / Chapter 4.8 --- Anti-fungal activity --- p.108 / Chapter Chapter 5 --- CONCLUSION --- p.109 / Chapter SECTION 3: --- Purification and Characterization of antifungal peptide from buckwheat seeds Fagopyrum esculentum / Chapter Chapter 1 --- INTRODUCTION / Chapter 1.1 --- Plant antiftmgal proteins --- p.110 / Chapter 1.2 --- Classification of antifungal proteins --- p.110 / Chapter 1.3 --- Distribution of antifungal proteins in plants --- p.111 / Chapter 1.4 --- Mechanisms of antifungal activity --- p.111 / Chapter 1.5 --- Future Perspectives of Antifungal proteins --- p.112 / Chapter 1.6 --- Antifungal peptide from Buckwheat --- p.112 / Chapter 1 .7 --- Objectives of the present study --- p.113 / Chapter Chapter 2 --- MATERIALS AND METHODS --- p.114 / Chapter Chapter 3 --- EXPERIMENTAL RESULTS / Chapter 3.1 --- Purification and sequence determination --- p.118 / Chapter 3.2 --- Effect on anti-fungal activity --- p.118 / Chapter 3.3 --- Effect of temperature and pH on antifungal activity --- p.118 / Chapter 3.4 --- Effect of the antifungal peptide on tumor cells --- p.119 / Chapter 3.5 --- Effect of antifungal peptide on HIV-1 Reverse transcriptase Activity --- p.119 / Chapter 3.6 --- Effect of antifungal peptide on spleen cells and NO Production --- p.119 / Chapter Chapter 4 --- DISCUSSION / Chapter 4.1 --- Purification scheme and N-terminal sequence --- p.130 / Chapter 4.2 --- Antifungal Activity --- p.131 / Chapter 4.3 --- Physical stability --- p.131 / Chapter 4.4 --- Anti-proliferative activity toward cancer cells --- p.131 / Chapter 4.5 --- HTV-1 Reverse Transcriptase Inhibitory activity --- p.132 / Chapter 4.6 --- Mitogenic activity and nitric oxide production --- p.132 / Chapter Chapter 5 --- CONCLUSION --- p.133 / OVERALL CONCLUSION --- p.134 / REFERENCES --- p.136
46

Determinação do valor da heptoglobina sérica para diagnóstico de hemólise na síndrome HELLP /

Menegazzo, Ana Barbara Bordignon Rodrigues. January 2014 (has links)
Orientador: Joelcio Francisco Abbade / Banca: José Carlos Peraçoli / Banca: Francisco Lázaro Pereira de Souza / Resumo: INTRODUÇÃO: A síndrome HELLP é uma complicação severa da pré-eclâmpsia, caracterizada por hemólise, elevação das enzimas hepáticas e trombocitopenia. Apesar de haver padronização dos valores laboratoriais que definem a síndrome HELLP, ainda existe dificuldade para a caracterização da hemólise. OBJETIVO: Avaliar o valor de haptoglobina que determina a hemólise nas pacientes com síndrome HELLP. MÉTODOS: estudo transversal e prospectivo de gestantes e puérperas com de pré-eclâmpsia. Exame laboratorial avaliado: dosagem sérica de haptoglobina. Construção da curva ROC para determinar o valor de corte da haptoglobina para diagnóstico de hemólise na síndrome HELLP. RESULTADOS: O valor da haptoglobina para diagnóstico de hemólise em pacientes com síndrome HELLP foi de 0,26g/L. DISCUSSÃO: A melhor correlação observada foi a haptoglobina com a DHL, indicando que este é o melhor marcador de hemólise intravascular para o diagnóstico da síndrome HELLP. CONCLUSÃO: A dosagem sérica da haptoglobina nos casos de pré-eclâmpsia deve fazer parte dos exames de rotina para diagnóstico de hemólise intravascular da síndrome HELLP / Abstract: CONTEXT: HELLP syndrome is a severe complication of pre-eclampsia, caracterized by hemolysis, elevated liver enzymes and low platelet count. Although there are standardized laboratory values that define the HELLP syndrome, the difficulty still exists for the characterization of hemolysis. PURPOSE: to evaluate the haptoglobin value to diagnose the hemolysis in HELLP syndrome. METHODS: transversal and prospective study of pregnant and postdelivery women with pre-eclampsia. Laboratory tests evaluated: serum haptoglobin. ROC curve to determine the cutoff value of haptoglobin in the diagnosis of hemolysis in HELLP syndrome. RESULTS: The haptoglobin value for hemolysis diagnosis in HELLP syndrome was 0.26 g / L. DISCUSSION: The best correlation was with haptoglobin and DHL, indicating that this is the best marker of intravascular hemolysis for the diagnosis of HELLP syndrome. CONCLUSION: Serum haptoglobin in cases of pre-eclampsia should be part of routine tests for diagnosis of intravascular hemolysis in HELLP syndrome / Mestre
47

Molecular characterization of the haemolysin determinant of Vibrio cholerae O1 / Richard A. Alm.

Alm, Richard A. January 1989 (has links)
Includes an appendix of author's previously published papers. / Bibliography: leaves 123-160. / 160, [105] leaves, [30] leaves of plates : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Microbiology and Immunology, 1990
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Exercise induced hemolysis, inflammation and hepcidin activity in endurance trained runners

Peeling, Peter Daniel January 2009 (has links)
[Truncated abstract] Iron is a trace mineral used by the body in many physiological processes that are essential to athletic performance. Commonly, the body's iron stores are compromised by exercise via several well established mechanisms. One such mechanism is the destruction of red blood cells (hemolysis), in response to the mechanical stress and circulatory strain of exercise. Although it appears that a force-dependent relationship between the heel-strike of the running gait and ground contact exists, the effects of the intensity trained at and the ground surface type trained upon have not been documented. Similarly, the effects of a cumulative training stress (i.e. multiple daily sessions) has not been examined. In addition to hemolysis, exercise also invokes an inflammatory response that results in an up-regulation of the cytokine interleukin-6 (IL-6). This cytokine is the primary mediator of hepcidin expression, a liver-produced hormone that regulates iron metabolism in the gut and in macrophages. The influence of exercise on hepcidin expression is relatively unknown, and as such it is possible that this hormone may be a mitigating factor implicated in athletic-induced iron deficiency. Therefore, the purpose of this thesis was to investigate the effect of different training frequencies, intensities and ground surfaces on the hemolytic response. In addition, the impact of exercise-induced inflammation on hepcidin expression in the 24 h post-exercise was investigated, with the aim of determining whether this hormone may be a potential new mechanism associated with athletic-induced iron deficiency. Finally, an interaction between hemolysis and hepcidin activity was examined to investigate their potential combined effect on iron status in the 24 h post-exercise. ... Venous blood and urine samples were collected pre- and immediately post-exercise, and at 3 and 24 h of recovery. Samples were analysed for circulating levels of IL-6, free Hb, Hp, serum iron, ferritin and urinary hepcidin activity. At the conclusion of both the T1 and T2 interval runs, the free Hb and serum Hp were significantly increased (p<0.05) from pre-exercise levels. Furthermore, a cumulative effect of two running sessions was shown in the T2 trial, via a further significant fall in serum Hp. The IL-6 and hepcidin activity were significantly increased after each running session (p<0.05) with no cumulative effect seen. Serum iron and ferritin were significantly increased post-exercise after each interval run (p<0.05), but were not influenced by the addition of a prior LSD run 12 h earlier. As a result, this investigation showed a cumulative effect of consecutive training sessions on RBC destruction in male athletes. Furthermore, post-exercise increases to serum iron and hepcidin, and their interaction was suggested to have potential implications for an athlete's iron status. Overall, the findings of this thesis show that hemolysis is evident at the conclusion of endurance running, and is influenced by training intensity and frequency. The results enabled a time-line for hepcidin expression post-exercise to be established, and the implications of increases to the activity of this hormone, in association with the hemolytic changes seen with endurance exercise are discussed.
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Avaliação das atividades citotóxica e genotóxica de Taninos de Mimosa arenosa (Willd.) Poir. (MIMOSACEAE)

Goncalves, Gregorio Fernandes 07 October 2011 (has links)
Made available in DSpace on 2015-05-14T12:59:27Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 530480 bytes, checksum: 56489dd34103dd0c6bf8b9c5101d98cb (MD5) Previous issue date: 2011-10-07 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Natural products represent a rich source of biologically active compounds and are an example of molecular diversity, with recognized potential in the discovery and development of new drugs The genus Mimosa is distributed in various environments and various types of vegetation in tropical regions. In northeast Brazil can be found in the state of Bahia, Pernambuco and Paraíba. Many species of Mimosa are economically important, however, few biological studies of plants of this kind were carried out so far, with proven antibacterial and allelopathic activity. Therefore, the objective of this study was to evaluate the cytotoxic and genotoxic activities of the species M. arenosa (Willd.) Poir. tannins. The minimum inhibitory concentration (MIC) obtained for Pseudomonas aeruginosa ATCC 8027 and Pseudomonas aeruginosa ATCC 25619 was 1000μg, for Bacillus subtilis ATCC 0516 and Escherichia coli ATCC 2536 MIC was 500μg, as to the strains of Staphylococcus aureus ATCC 6538, Staphylococcus aureus ATCC 25925 and Escherichia coli ATCC 10536 the amount of tannin required to inhibit the growth of these bacteria was 250μg. The antibacterial activity exerted by Mimosa arenosa tannins against all strains tested was bacteriostatic. In the evaluation of cytotoxicity in any of the tested concentrations of tannins M. arenosa no caused significant hemolysis of red cells in any of the blood groups tested. However, the tannins were unable to protect the erythrocyte cells when exposed to hypotonic salt solutions. The tannins were not affected in any of the oxidant concentrations tested but they have reduced the oxidation of hemoglobin when exposed to an oxidizing agent. The tannins were not able to induce mutations but showed antimutagenic effect in strains of S. thyphimurium. Tannins did not induce structural cromossomal damage and/or numerical in erythrocytes of mouse. / Os produtos naturais representam uma rica fonte de compostos biologicamente ativos e são um exemplo de diversidade molecular, com reconhecido potencial na descoberta e desenvolvimento de novos medicamentos. O gênero Mimosa se distribui nos mais variados ambientes e nos diversos tipos de vegetação das regiões tropicais. No nordeste do Brasil pode ser encontrado nos estados da Bahia, Pernambuco e Paraíba. Muitas espécies de Mimosa são economicamente importantes, no entanto, poucos estudos biológicos de plantas desse gênero foram realizados ate o momento, sendo comprovadas atividade antimicrobiana e alelopática. Sendo assim, o objetivo deste trabalho foi avaliar as atividades citotóxica e genotóxica de taninos da espécie Mimosa arenosa (Willd.) Poir. A concentração inibitória mínima (CIM) obtida para Pseudomonas aeruginosa ATCC 8027 e Pseudomonas aeruginosa ATCC 25619 foi 1000μg, para Bacillus subtilis ATCC 0516 e Escherichia coli ATCC 2536 a CIM foi de 500μg, já para as linhagens de Staphylococcus aureus ATCC 6538, Staphylococcus aureus ATCC 25925 e Escherichia coli ATCC 10536 a quantidade necessária de taninos para inibir o crescimento dessas bactérias foi de 250μg. A atividade antibacteriana exercida pelos taninos de M. arenosa frente a todas as linhagens testadas foi bacteriostática. Na avaliação de citotoxicidade, em nenhumas das concentrações testadas, os taninos de M. arenosa causaram hemólise significativa dos eritrócitos em nenhum dos grupos sanguineos testados. Entretanto, os taninos não conseguiram proteger as células eritrocitárias quando expostas a soluções hipotônicas de sal. Os taninos não apresentaram efeito oxidante em nenhuma das concentrações testadas, entretanto estes conseguiram reduzir a oxidação da hemoglobina quando expostas a um agente oxidante. Os taninos não foram capazes de induzir mutações, porém apresentaram efeito antimutagênico em linhagens de S. thyphimurium e também não promoveram dano cromossômico estrutural e/ou numérico em eritrócitos de camundongo in vivo .
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Determinação do valor da heptoglobina sérica para diagnóstico de hemólise na síndrome HELLP

Menegazzo, Ana Barbara Bordignon Rodrigues [UNESP] 08 August 2014 (has links) (PDF)
Made available in DSpace on 2015-01-26T13:21:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-08-08Bitstream added on 2015-01-26T13:30:38Z : No. of bitstreams: 1 000797817.pdf: 449554 bytes, checksum: 7adc756b2ac04e5d1cbc6be34fa7a04e (MD5) / Introdução: A síndrome HELLP é uma complicação severa da pré-eclâmpsia, caracterizada por hemólise, elevação das enzimas hepáticas e trombocitopenia. Apesar de haver padronização dos valores laboratoriais que definem a síndrome HELLP, ainda existe dificuldade para a caracterização da hemólise. OBJETIVO: Avaliar o valor de haptoglobina que determina a hemólise nas pacientes com síndrome HELLP. MÉTODOS: estudo transversal e prospectivo de gestantes e puérperas com de pré-eclâmpsia. Exame laboratorial avaliado: dosagem sérica de haptoglobina. Construção da curva ROC para determinar o valor de corte da haptoglobina para diagnóstico de hemólise na síndrome HELLP. RESULTADOS: O valor da haptoglobina para diagnóstico de hemólise em pacientes com síndrome HELLP foi de 0,26g/L. DISCUSSÃO: A melhor correlação observada foi a haptoglobina com a DHL, indicando que este é o melhor marcador de hemólise intravascular para o diagnóstico da síndrome HELLP. CONCLUSÃO: A dosagem sérica da haptoglobina nos casos de pré-eclâmpsia deve fazer parte dos exames de rotina para diagnóstico de hemólise intravascular da síndrome HELLP / Context: HELLP syndrome is a severe complication of pre-eclampsia, caracterized by hemolysis, elevated liver enzymes and low platelet count. Although there are standardized laboratory values that define the HELLP syndrome, the difficulty still exists for the characterization of hemolysis. PURPOSE: to evaluate the haptoglobin value to diagnose the hemolysis in HELLP syndrome. METHODS: transversal and prospective study of pregnant and postdelivery women with pre-eclampsia. Laboratory tests evaluated: serum haptoglobin. ROC curve to determine the cutoff value of haptoglobin in the diagnosis of hemolysis in HELLP syndrome. RESULTS: The haptoglobin value for hemolysis diagnosis in HELLP syndrome was 0.26 g / L. DISCUSSION: The best correlation was with haptoglobin and DHL, indicating that this is the best marker of intravascular hemolysis for the diagnosis of HELLP syndrome. CONCLUSION: Serum haptoglobin in cases of pre-eclampsia should be part of routine tests for diagnosis of intravascular hemolysis in HELLP syndrome

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