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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.
21

Determinação dos mecanismos de ação envolvidos no efeito antiulcerogênico, antidiarreico e anti-inflamatório da "Insulina Vegetal" (Cissus sicyoides Linneu) em modelos animais /

Beserra, Fernando Pereira. January 2014 (has links)
Orientador: Clélia Akiko Hiruma Lima / Coorientador: Lúcia Regina Machado da Rocha / Banca: Cláudia Helena Pellizzon / Banca: Luis Vitor Silva Sacramento / Resumo: Cissus sicyoides (Linneu) pertencente à família Vitaceae é uma planta nativa do Caribe, América do Sul e especialmente no Brasil, onde é conhecida como ―Insulina vegetal‖. O chá das folhas desta espécie é utilizada popularmente como anti-inflamatório, anti-hipertensivo, antitérmico, antidiabético, antireumático, contra infecções respiratórias, dislipidemias, distúrbios gastrointestinais e indigestão, para anemia, acidente vascular cerebral, tremores e como ativador da circulação sanguínea. A análise fitoquímica das partes aéreas de C. sicyoides mostra a presença de flavonóides glicosilados, e várias atividades biológicas já foram descritas para esta espécie, dentre elas, atividade gastroprotetora do extrato metanólico de suas folhas. O objetivo deste trabalho foi investigar a atividade antiulcerogênica do extrato hidroalcoólico das folhas de C. sicyoides (EHCS), elucidar os mecanismos envolvidos no efeito antiulcerogênico, em processos inflamatórios e em modelos experimentais de diarreia em roedores. A administração oral do EHCS nas doses 250 e 500 mg/Kg protegeu a mucosa gástrica da ação dos agentes lesivos etanol e anti-inflamatório não esteroidal em ratos Wistar machos. O EHCS na menor dose efetiva (250 mg/Kg) não alterou os parâmetros bioquímicos do suco gástrico em modelo de ligadura do piloro e não preveniu a úlcera duodenal induzida por cisteamina hidroclorídrica. Este extrato aumentou a quantidade de muco aderido à parede gástrica, restabeleceu o fluxo sanguíneo atuando como regulador na microcirculação e a ação gastroprotetora do extrato é dependente de óxido nítrico por atuação da enzima óxido nítrico sintase induzível (iNOS), ao mesmo tempo que independe de grupamentos sulfidrilas e receptores vanilóides. Este extrato possui propriedade antioxidante ao promover a proteção das lesões gástricas induzidas por isquemia-reperfusão, reduzindo ... / Abstract: Cissus sicyoides (Linneu) belongs to the Vitaceae family is a plant native to the Caribbean, South America and especially in Brazil, where it is known as "vegetable insulin". The tea from leaves of this species is popularly used as anti-inflammatory, anti-hypertensive, antipyretic, antidiabetic, antirheumatic, against respiratory infections, dyslipidemia, gastrointestinal disorders and indigestion, for anemia, cerebral tremors and as an activator of circulation blood. The phytochemical analysis of aerial parts of C. sicyoides showed predominantly the presence of glycosylated flavonoids and various biological activities have been described for this species, among them, gastroprotective activity of the methanol extract of its leaves. With these considerations, the aim of this study was to investigate the antiulcer activity of hydroalcoholic extract of C. sicyoides (HECS), as well as to elucidate the mechanisms involved in antiulcerogenic effect, inflammatory processes and in experimental models of diarrhea in rodents. The HECS in doses 250 and 500 mg/Kg protected the gastric mucosa from the damaging agents action, ethanol and anti-inflammatory non-steroidal when administered orally to male Wistar rats. The EHCS at the lowest effective dose (250 mg/Kg) didn't alter biochemical parameters of gastric juice in pylorus ligature model and did not prevent the duodenal ulcer induced by cysteamine hidroclorídrica. This extract increased the amount of mucus adhered to the gastric wall, restored blood flow in the microcirculation acting as a regulator and gastroprotective activity of the extract is dependent on nitric oxide activity of the enzyme inducible nitric oxide synthase (iNOS), while independent groups of sulfhydryl and vanilloid receptors. This extract has antioxidant properties to promote the protection of gastric lesions induced by ischemia-reperfusion injury by reducing lipid peroxidation (LPO) and ... / Mestre
22

Atividade antimicrobiana in vitro de extratos hidroetanólicos de Astronium sp incorporados ou não em sistemas nanoestruturados /

Bonifácio, Bruna Vidal. January 2014 (has links)
Orientador: Taís Maria Bauab / Banca: Izabela Dutra Alvim / Banca: Carlos Henrique Gomes Martins / Resumo: Os fitoterápicos têm apresentado resultados surpreendentes no tratamento de doenças crônicas, principalmente do trato digestório (úlceras gástricas e duodenais, colite ulcerativa e doença de Crohn), diabetes e câncer. A Política Nacional de Plantas Medicinais e Fitoterápicos - PNPMF (Ministério da Saúde - MS) propõe o estudo de diversas espécies vegetais, dentre estas, plantas do gênero Astronium (Anacardiaceae), que reúne espécies como Astronium fraxinifolium, Astronium graveolens e Astronium urundeuva, com propriedades anti-inflamatória, antiulcerogênica, cicatrizante e antimicrobiana. Nesse contexto, a inclusão da tecnologia no aprimoramento de plantas medicinais deve ser estimulada já que a estratégia de incorporação de extratos vegetais em sistemas nanoestruturados tem otimizado suas propriedades. A atividade antimicrobiana dos extratos incorporados ou não em sistemas nanoestruturados foi avaliada pela técnica de microdiluição frente aos micro-organismos Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 25923), Salmonella setubal (ATCC 19196), Helicobacter pylori (ATCC 43504) e Candida albicans (ATCC 18804). Os extratos vegetais foram testados nas concentrações de 1000 a 7,81 μg/mL e como controle foram utilizados a amoxicilina (100 μg/mL) para H. pylori; a ampicilina (50 μg/mL) para as demais bactérias, e a anfotericina B (32 μg/mL) e fluconazol (256 μg/mL) para C. albicans. Após incubação a 37 ºC/72 horas sob condição de microaerofilia para H. pylori; 37 ºC/24 horas para as demais bactérias e 37 ºC/48 horas para a levedura, foram realizadas as leituras espectrofotométrica e visual, com os reveladores resazurina 0,01% (bactérias), e cloreto de 2,3,5-trifeniltetrazólio 2% - TTC (levedura) para a determinação da concentração inibitória mínima (CIM). A incorporação foi feita em um sistema nanoestruturado constituído por 10%... / Abstract: Herbal medicines have shown amazing results for the treatment of chronic diseases, especially the ones of the digestive tract (gastric and duodenal ulcers, ulcerative colitis and Crohn's disease), diabetes and cancer. The National Policy of Medicinal Plants and Herbal Medicines (Ministry of Health) proposes the study of several plant species, including plants containing the genus Astronium (Anacardiaceae) that includes species such as A. fraxinifolium, A. graveolens and A. urundeuva, which comprise anti-inflammatory, anti-ulcerogenic, healing and antimicrobial properties. In this context, the inclusion of technology in the improvement of medicinal plants should be encouraged since the strategy to incorporate plant extracts in nanostructured systems has optimized their properties. The antimicrobial activity of the extracts, which were incorporated or not into nanostructured systems, was evaluated by microdilution technique for the microorganisms Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 25923), Salmonella setubal (ATCC 19196), Helicobacter pylori (ATCC 43504) and Candida albicans (ATCC 18804). The plant extracts were tested at concentrations from 1000 to 7.81 μg/mL, and the following medications were used to check in order to see if they will work with each type of microorganisms: amoxicillin (100 μg/mL) for H. pylori; ampicillin (50 μg/mL) for the other bacteria, amphotericin B (32 μg/mL) and fluconazole (256 μg/mL) for C. albicans. After the incubation at 37 ºC/72 hours under microaerophilic condition for H. pylori; 37 ºC/24 hours for the other bacteria and 37 °C/48 hours for the yeast, spectrophotometric and visual readings were performed, with the developers 0.01% resazurin (bacteria) and 2% 2,3,5-triphenyltetrazolium chloride in order to determine the minimum inhibitory concentration (MIC). The incorporation was prepared into a nanostructured system com... / Mestre
23

The flavonoids and phenolic acids of the genus Silphium and their chemosystematic and medicinal value

Williams, Jeffrey Douglas, January 1900 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.
24

Development of analytical methodologies for the determination of metals and organic acids in environmental and traditional Chinese medicine studies by capillary electrophoresis

Tung, Ho-shan. January 2000 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2001. / Includes bibliographical references.
25

The effects of gelomyrtol forte on human ciliary beat frequency and intracellular cyclic adenosine monophosphate in vitro

Kwok, Pui-wai., 郭佩瑋. January 2007 (has links)
published_or_final_version / Medicine / Master / Master of Research in Medicine
26

Bio-active constituent from Yinqiaosan has anti-influenza and anit-inflammatory effect

Law, Hing-yee, 羅興怡 January 2014 (has links)
Influenza epidemics have become a major public health concern worldwide. According to the World Health Organization, the annual epidemics results in about three to five million cases of severe illness, and about 250 to 500 thousand deaths. Recurring emergence of new influenza viruses and viruses that are resistant to currently approved antiviral medications pose a critical need to explore new or alternative medications. A classical Traditional Chinese Medicine (TCM) decoction consisting of nine herbs, named Yinqiaosan (YQS, 銀翹散), has a long history for treating respiratory diseases in China. However, the efficacy of YQS has not been investigated mechanistically. In the present study, the effectiveness of YQS in treating influenza virus infection was examined. The potential mechanisms of action of two active compounds present in one of the component herbs of YQS were also investigated. Results showed that YQS increased the survival rate of the mice in an in vivo influenza virus infection model with significant reduction in lung viral titers. In order to further delineate the mechanisms of action of YQS, compounds present in a principal ingredient of YQS were examined for antiviral and immunomodulatory effects. In screening a panel of fractions extracted from YQS, forsythoside A was demonstrated to suppress the viral titers of a wide range of influenza viruses including the oseltamivir-resistant and the 2009 pandemic H1N1 viruses. Through electron microscopy, slow or abnormal viral budding events were observed upon forsythoside A treatment during influenza virus infection. Western blot analysis revealed a reduced influenza virus M1 protein expression. As previous report showed that assembly of viral components into an infectious particle required a threshold level of M1 protein, reduced M1 expression in the cells treated with forsythoside A may contribute to the virus replication suppression. On the other hand, innate immune responses provide first line protection against influenza virus infections. However, excessive responses often result in tissue damage. Cyclooxygenase (COX)-2 is an immunomodulatory factor that has been shown to play a role in the pathogenesis of influenza viruses. A previous COX-2 knock-out mice model showed that COX-2 deficiency is beneficial to the host during influenza viral infection, in which mortality was significantly reduced. Furthermore, during H5N1 infection, it has been shown that COX-2 level significantly increased and it played an essential role in coordinating the productions of inflammatory cytokines, while in another study, pharmacological inhibition of COX-2 suppressed H5N1 virus replication in primary human macrophages. In view of the roles of COX-2 during influenza virus infection, the presence of compound in YQS that reduces the influenza virus-induced COX-2 level was examined. Present results showed that jacaranone not only reduced the influenza virus-induced cyclooxygenase (COX)-2 mRNA level, it also suppressed the subsequent production of prostaglandin E2 level in primary human macrophages. At the same time, jacaranone inhibited the virus induced-activations of ERK1/2 and Akt, which are involved in the COX-2 induction. Jacaranone also suppressed, at least in part, the COX-2 mRNA level at the transcriptional level by inhibiting the nuclear translocation of NF-κB. To conclude, TCM has been recognized as an important part in complementary and alternative medicine and it is an ample source of antimicrobial drugs. The use of a mixture of herbs is the major therapeutic approach of TCM in which, the principal ingredients provide the main therapeutic actions while the others enhance the effects or diminish the side effects of the principal ones. Some components act mainly for symptomatic control. The present study not only supports the efficacy of YQS, but also gives evidences to an active antiviral compound and an immunomodulatory compound found in YQS. They may act as either principle or supporting components depending on the purpose of application. This study provides new insights on future novel drug development from the existing wisdom of TCM. / published_or_final_version / Paediatrics and Adolescent Medicine / Doctoral / Doctor of Philosophy
27

The flavonoids and phenolic acids of the genus Silphium and their chemosystematic and medicinal value

Williams, Jeffrey Douglas 28 August 2008 (has links)
Not available
28

Anti-inflammatory and anti-bacterial activity of South African Erythrina species.

Pillay, Candice Claudia Natasha. 17 December 2013 (has links)
An investigation was undertaken to determine whether Erythrina species indigenous to South Africa contained the same type of compounds as Erythrina species not found in South Africa and to determine whether they displayed any anti-inflammatory and antibacterial activity. Phytochemical analysis was conducted using thin layer chromatography. A great similarity was found in the leaf profiles of the species being studied. The leaf and bark extracts of E. caffra and E. lysistemon appear to have similar profiles when viewed under normal light and ultraviolet light, (254 and 366 nm). These two species have similar banding patterns when stained with fast blue reagent for flavonoids and potassium hydroxide reagent for coumarins. The five species that were tested appear to contain alkaloids, flavonoids, coumarins and triterpenes just like the species not found in South Africa from this genus. Dried bark and leaves from E. caffra, E. humeana, E. latissima, E. lysistemon and E. zeyheri were screened for anti-inflammatory and anti-bacterial activity. Ethanol, ethyl acetate and water extracts were screened for both anti-inflammatory and anti-bacterial activity. The cyclooxygenase bioassay was used to test for anti-inflammatory activity. The ethanol and ethyl acetate extracts generally displayed activity while the water extracts displayed no activity for both the bark and the leaves. The bark generally displayed more cyclooxygenase inhibitory activity than the leaves. The bark of E. caffra and E. lysistemon displayed the highest cyclooxygenase inhibitory activity. The disc diffussion bioassay was used to screen for anti-bacterial activity. Anti-bacterial activity was only detected in the water extracts of the leaves. The water extracts of the bark showed very little or no activity. The bark yielded more anti-bacterial activity than the leaves. Anti-bacterial activity was mainly displayed against Gram positive bacteria. The bark of E. caffra and E. lysistemon displayed the highest anti-bacterial activity. On the basis of the screening results it was decided to use bioasssay guided fractionation in an attempt to isolate putative anti-inflammatory and anti-bacterial compounds. A hexane extract from the bark of E. lysistemon was prepared and purified using a range of chromatographic methods. Vacuum liquid chromatography, separation using a chromatotron, thin layer chromatography and high performance liquid chromatography were used to isolate anti-inflammatory compound(s). The isolation proved to be unsuccessful as the pure compound had no cyclooxygenase inhibitory activity. It was subsequently determined that the compounds were lost during the HPLC procedure. An ethanolic extract of the bark of E. Iysistemon was purified in an attempt to isolate an anti-bacterial compound(s). Vacuum liquid chromatography and separation using the chromatotron was used to purify the crude extract. The more sensitive microtitre bioassay was used to test for anti-bacterial activity against S. aureus. The isoflavone, Wighteone was isolated. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2000.
29

The effects of Sutherlandia frutescens in cultured renal proximal and distal tubule epithelial cells.

Phulukdaree, Alisa. January 2009 (has links)
Sutherlandia frutescens (SF), an indigenous medicinal plant to South Africa (SA), is traditionally used to treat a diverse range of illnesses including cancer and viral infections. The biologically active compounds of SF are polar, thus renal elimination increases susceptibility to toxicity. This study investigated the antioxidant potential, lipid peroxidation, mitochondrial membrane potential and apoptotic induction by SF on proximal and distal tubule epithelial cells. Cell viability was determined using the MTT assay. Mitochondrial membrane potential was determined using a flow cytometric JC-1 Mitoscreen assay. Cellular glutathione and apoptosis were measured using the GSH-GloTM Glutathione assay and Caspase-Glo® 3/7 assay, respectively. The IC50 values from the cell viability results for LLC-PK1 and MDBK was 15 mg/ml and 7 mg/ml, respectively. SF significantly decreased intracellular GSH in LLC-PK1 (p < 0.0001) and MDBK (p < 0.0001) cells. Lipid peroxidation increased in LLC-PK1 (p < 0.0001) and MDBK (p < 0.0001) cells. JC-1 analysis showed that SF promoted mitochondrial membrane depolarization in both LLC-PK1 and MDBK cells up to 80% (p < 0.0001). The activity of caspase 3/7 increased both LLC-PK1 (11.9-fold; p < 0.0001) and MDBK (2.2-fold; p < 0.0001) cells. SF at high concentrations plays a role in increased oxidative stress, altered mitochondrial membrane integrity and promoting apoptosis in renal tubule epithelia. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2009.
30

An in vivo study to determine the effects of Ochratoxin A and Sutherlandia frutescens in male Wistar rats.

Durgiah, Raveshni. January 2009 (has links)
Ochratoxin A (OTA), a nephrotoxic mycotoxin, is a contaminant of several agricultural food products consumed by animals and humans. Apart from renal toxicity, in particular renal tumours, OTA may also result in teratogenicity, neurotoxicity and immunotoxicity. Sutherlandia frutescens, an indigenous medicinal plant, has shown significant potential in strengthening the immune system and in cancer treatment, with minimal side effects. The objective of this study was to determine the effects of OTA in male Wistar rats and ascertain if these effects may be reduced by S. frutescens. Rats were treated by intraperitoneal injection (i.p) with either a control (EtOH:dH20;30:70), S. frutescens (1.0mg/kg body weight), OTA (0.5mg/kg body weight) or a combination of OTA and S. frutescens for a period of 1 or 7 days (n=4). Genotoxicity and metabolic activity in peripheral blood mononuclear cells (PBMCs) were quantified using single cell gel electrophoresis (SCGE) and the methylthiazol tetrazolium (MTT) assay, respectively. Lymphocyte apoptosis and mitochondrial depolarisation were measured by flow cytometry. Fluorescence microscopy was utilised to determine renal tissue apoptosis (Hoechst staining) and OTA localisation using immunohistochemistry (IRC). SDS-PAGE and Western blot were utilised to determine protein expression in kidney tissue and serum. Ochratoxin A significantly reduced PBMC viability (14%) after 7 days, compared with Day 1 (p<0.001). Lymphocyte mitochondrial depolarisation was 56.5% and 66.2% in the OTA-only and combination groups, respectively after 7 days (p<0.001). Ochratoxin A produced an increase in DNA damage compared to the control (p<0.01). The renal tissue displayed typical signs of apoptosis such as chromatin condensation. Ochratoxin A was immunolocalised within the glomerulus. The protein analysis showed a decreased expression in the kidney mitochondrial protein fraction. Ochratoxin A preferentially bound to serum albumin and a 120kDa protein in the OTA-only and co-treatment groups after the 1-and 7-day regimes. Protein band intensities significantly decreased after the 7-day co-treatment (p<0.01). The data highlights that OTA toxicity is mediated by mitochondrial dysfunction. Furthermore, OTA disruptions in immune function may play a role in renal damage. / Thesis (M.Med.Sc.)-University of KwaZulu-Natal, Westville, 2009.

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