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Thesis ( |b(MSc. (Biochemistry)) -- University of Limpopo, 2017 / Medicinal plants have been used as a key source for medication and they remain to provide new therapeutic remedies to date. Extracts of Olea europaea subspecies africana leaves are used extensively in South Africa to treat various diseases traditionally. The diseases have been noted to be associated with free radicals, bacterial infections, and inflammation. However, there is little information about the antioxidant, antibacterial, and anti-inflammatory activities of the leaves of this plant in literature and the cytotoxicity of the leaf extracts is still a concern. The information about the Isolated compounds is also minimal hence this study was aimed at filling in those gaps in relation to the traditional use of the leaves in southern Africa and subsequently isolating and identifying the active compounds using bioassay-guided fractionation. Preliminary screening of the crude extracts for antioxidant, antibacterial and antiinflammatory activities indicated that the extracts possessed all biological activities. The presence of major phytochemicals in the crude extracts was determined through the use of standard chemical methods and TLC analysis. The colorimetric methods (Folin-Ciocalteau and Aluminum chloride) were used for quantification purposes. TLC-DPPH assay was used to screen antioxidant activities of the crude extracts. The observed activity was quantified using the spectrophotometric method of DPPH and reducing power. The antibacterial properties of the leaf extracts were determined by direct bioautography and the serial broth microdilution assay using E. coli, P. aeruginosa, E. faecalis and S. aureus as test bacteria. Screening of the acetone crude extract for anti-inflammatory activities was done using the LPSstimulated RAW 264.7, cells where the inhibition of ROS generation was studied. MTT assay was used to determine the cytotoxicity effects of the leaves. Isolation of bioactive compounds started with serial exhaustive extraction, followed by column chromatography packed with silica gel. NMR analysis was conducted to identify the isolated compound. The results revealed the presence of tannins, terpenoids, steroids and flavonoids with the total phenolic (99.67 ± 2.52 mg of GAE/g) and tannin content (114.33 ± 9.02 mg of GAE/g) found in high amounts. All crude extracts exhibited antioxidant activities and the antioxidant activity quantified via the DPPH assay demonstrated to xxi have EC50 value of 1.05 ± 0.0071 mg/mL. The reducing capacity was found to be dose-dependent and great significance was seen at concentration 0.5 mg/mL to 1 mg/mL that was about 2/3 of that of L-ascorbic acid (standard) at a similar concentration. Screening of the crude extracts for antibacterial activity revealed that all crude extracts except n-hexane and water extracts, inhibited the growth of the tested bacteria on the previously developed TLC plates. The activity was seen as clear zones on the bioautograms. Serial broth microdilution assay indicated that dichloromethane, acetone and ethanol had average MIC values of 0.30, 0.32 and 0.35 mg/mL against all tested bacteria, respectively. Good anti-inflammatory activity of the crude extract was demonstrated at the highest concentration of 0.90 mg/mL. MTT assay indicated that the crude extract had no adverse cytotoxic effects. This was demonstrated by the LC50 values greater than 20 µg/mL and considered non-cytotoxic according to the National Cancer Institute (NCI). Isolation following the bioassay-guided-fractionation resulted in the selection of acetone extract to isolate the bioactive compounds from as it demonstrated good antioxidant and antibacterial activities. Fractionation of the compound by column chromatography yielded three combinations (pools) of fractions and of the three from which only pool 1 was considered for further fractionation. NMR spectra information identified the isolated compound as a mixture of ursolic acid (minor) and oleanolic acid (major). This compound had antibacterial and anti-inflammatory activities and no cytotoxic effects. The leaves of Olea europaea subspecies africana have been proven to possess antioxidant, antibacterial and anti-inflammatory properties. Evaluation of the biological activities of the crude extracts was to validate the use of the leaves traditionally to treat free radical and bacterial-related diseases and potential drug that are safe and has less side effects may be produced from the leaves. / National Research Foundation (NRF)

<p>The exploitation of natural resources in general and biodiversity in particular by human beings, is remarked to be associated with unsustainable practices that place the survival of these resources at stake. An assessment of the exploitation of <em>prunus africana</em> around the mount Cameroon region can be linked with the trend of unsustainable exploitation prevailing in other parts of the world. <em>Prunus africana</em>, is a tree cherished by the local population for its varied values, with its medicinal values propelling it to international popularity. This has been characterized by the massive demand for its bark by western pharmaceutical companies. The huge demand of the tree in the international market is remarked to be a major factor that contributed to the tree’s mass unsustainable exploitation by the local population in the studied region. This paper has looked at the factors responsible for the mass unsustainable exploitation of <em>prunus</em> and the measures that local based organizations, MOCAP-CIG and MCP had adopted to promote participatory management of the tree. Three major factors; poverty, the issuing of 50 exploitation permits and international demand were identified to have contributed to the involvement of the local population in unsustainable exploitation of the tree. The concept of sustainable development was used as the theoretical framework to examine if the three dimensions can be attained without one affecting the other. The results showed that it is quite difficult to achieve this especially in the case of  the exploitation and conservation of <em>prunus africana</em>.</p>

The exploitation of natural resources in general and biodiversity in particular by human beings, is remarked to be associated with unsustainable practices that place the survival of these resources at stake. An assessment of the exploitation of prunus africana around the mount Cameroon region can be linked with the trend of unsustainable exploitation prevailing in other parts of the world. Prunus africana, is a tree cherished by the local population for its varied values, with its medicinal values propelling it to international popularity. This has been characterized by the massive demand for its bark by western pharmaceutical companies. The huge demand of the tree in the international market is remarked to be a major factor that contributed to the tree’s mass unsustainable exploitation by the local population in the studied region. This paper has looked at the factors responsible for the mass unsustainable exploitation of prunus and the measures that local based organizations, MOCAP-CIG and MCP had adopted to promote participatory management of the tree. Three major factors; poverty, the issuing of 50 exploitation permits and international demand were identified to have contributed to the involvement of the local population in unsustainable exploitation of the tree. The concept of sustainable development was used as the theoretical framework to examine if the three dimensions can be attained without one affecting the other. The results showed that it is quite difficult to achieve this especially in the case of  the exploitation and conservation of prunus africana.

OBJECTIUS: Descriure la situació epidemiològica de la tripanosomosi humana africana (THA), també coneguda com malaltia de la son, en el focus de Quiçama, província del Bengo, Angola, i establir un programa de control per la THA.METODOLOGIA: El 1997, 8.796 persones (la població de 31 poblats) van ser examinades serològicament pel Trypanosoma brucei gambiense, l'agent causal de la THA. El 1998 i 1999, les enquestes es van dur a terme en els poblats on s'havien identificat casos de THA el 1997. Els individus van ser examinats amb el test d'aglutinació sobre cartolina per la tripanosomosi (CATT) i posteriorment examinats per determinar la presencia del paràsit. Els individus CATT-positiu en els quals la presencia del paràsit no fou confirmada van ser examinats posteriorment utilitzant el CATT en sèrum diluït, i els qui presentaven un títol d'anticossos superior o igual a ¼ se'ls va realitzar un seguiment seroparasitològic. 16 individus amb un títol d'anticossos inferior a ¼ van ser considerats com no infectats d'acord amb els resultats obtinguts en un estudi previ en el qual es va determinar el títol d'anticossos en un grup de casos confirmats parasitològicament. 86 individus amb un títol final superior o igual a ¼ van ser considerats sospitosos de tripanosomosi i van ser seguits des de juliol 1997 fins juliol 1998 amb controls cada tres mesos.Els malalts amb 10 o menys leucòcits/microlitre i sense tripanosomes en el líquid cefaloraquidi (LCR) van ser classificats com primer estadi de la malaltia. El control vectorial no va ser considerat necessari o possible.RESULTATS: Les principals àrees de transmissió eren a les vores del riu Kwanza amb 5,042 habitants. El 1997 la prevalença de la THA era de 1,97% però va disminuir fins 0,55% el 1998 i 0,33% el 1999. La taxa de recaigudes fou de 3% en els pacients tractats amb pentamidina i 3,5% en els pacients tractats amb melarsoprol. En els pacients tractats amb pentamidina, no va haver-hi diferència en la taxa de recaigues dels pacients amb un LCR inicial de 0-5 leucòcits/microlitre o 6-10 leucòcits/microlitre. La taxa global de mortalitat va ser de 0,6% i la taxa d'encefalopaties arsenicals reactives entre els pacients tractats amb melarsoprol fou de 1,7%. Desprès d'un any de seguiment de casos CATT-positiu sense confirmació parasitològica, 32 individus en els quals el títol d'anticossos va disminuir per sota de ¼ van ser considerats com no infectats, 22 van ser confirmats mitjançant l'observació del paràsit, 17 van continuar en seguiment perquè el seu títol d'anticossos continuava igual o superior a 1/8 però el paràsit no fou observat. 15 individus no es van presentar durant el seguiment. Tenint en compte el criteri habitual només els casos confirmats parasitològicament foren tractats. No obstant això, si s'hagués decidit tractar els individus en els quals no es va poder demostrar la presència del paràsit però que tenien un títol final d'anticossos superior a 1/8, 22 individus inicialment no confirmats però realment infectats s'haurien tractat precoçment, mentre que 5 individus no infectats s'haurien tractat innecessàriament.CONCLUSIÓ: La descripció de la situació epidemiològica de la malaltia va ser actualitzada i les àrees de transmissió van ser definides. Els mètodes de control utilitzats van permetre una reducció de la prevalença de la malaltia. La titulació d'anticossos utilitzant el CATT en sèrum o plasma és útil per prendre decisions a nivell terapèutic. / OBJECTIVE: To update the epidemiological status of human African trypanosomiasis (HAT), also known as sleeping sickness, in the Quicama focus, province of Bengo, Angola, and to establish a HAT control programme.METHODS: In 1997, 8796 people (the population of 31 villages) were serologically screened for "Trypanosoma brucei gambiense". In 1998 and 1999, surveys were carried out in villages where HAT cases had been identified in 1997. Individuals were screened using the card agglutination trypanosomiasis test (CATT), and then examined for the presence of the parasite. CATT-positive individuals in whom the presence of the parasite could not be confirmed were further tested with the CATT using serum dilutions, and those with a positive antibody end titre of 1-in-4 or above were followed-up. Patients with &#8804;10 white cells/microl and no trypanosomes in their cerebrospinal fluid (CSF) were classified as being in the first stage of the disease. Vector control was not considered necessary or feasible. FINDINGS: The main transmission areas were on the Kwanza riverbanks, where 5042 inhabitants live. In 1997, the HAT prevalence was 1.97%, but this decreased to 0.55% in 1998 and to 0.33% in 1999. The relapse rate was 3% in patients treated with pentamidine and 3.5% in patients treated with melarsoprol. In patients treated with pentamidine, there was no difference in the relapse rate for patients with initial CSF white cell counts of 0-5 cells/ microl or 6-10 cells/microl. The overall mortality rate was 0.6% and the rate of reactive arsenical encephalopathy among the melarsoprol-treated patients was 1.7%. 86 individuals with end titres &#8805; 1/4 were followed-up with controls every three months. After one year, 32 individuals whose antibody titres dropped < 1/4 were considered non infected, 22 were confirmed by demonstration of parasites, 17 were further followed-up because antibody titres remained &#8805; 1/8 but parasites could not be found. Fifteen individuals did not show up for testing.CONCLUSION: The epidemiological status of the disease was updated and the transmission areas were defined. The control methods implemented allowed the disease prevalence to be reduced. CATT titration on diluted serum or plasma is useful for making therapeutical decisions.

Thesis (Ph. D., Natural Resources)--University of Idaho, May 2007. / Major professor: Jay O'Laughlin. Includes bibliographical references (leaves 76-83). Also available online (PDF file) by subscription or by purchasing the individual file.

Zugl.: Marburg, Univ., Diss., 2005.

Orientador: Percival Tirapeli / Banca: Renata Bittencourt / Banca: Nelson Fernando Inocêncio / Banca: Wagner Leite Viana / Banca: José Leonardo do Nascimento / Resumo: Esta proposta de pesquisa de doutorado possui alguns pontos de investigação, sendo três deles os mais pertinentes. O primeiro é uma breve revisão da presença de artistas afrodescendentes na História da Arte do Brasil pretendendo tanto relembrar e revelar personagens quanto observar como as Artes Visuais produzidas por artistas afrodescendentes foram observadas, registradas e nomeadas ao longo dos séculos por pesquisadores, críticos e historiadores. O segundo propõe a reflexão acerca da transposição e do emprego do termo "afro-brasileiro" ou "afro-brasileira" dos Estados Unidos da América para o Brasil na área de Artes Visuais, com fins de categorização da produção de artistas afrodescendentes, que possuem ou não pesquisas temáticas, conceituais, estéticas e/ou poéticas voltadas às questões relacionadas à história do segmento afrodescendente da população. Por fim, o terceiro se presta a apresentar e a analisar as produções de artistas afrodescendentes brasileiros e estadunidenses que demonstraram interesse por elaborar obras cujas visualidades e estéticas estivessem em diálogo com as questões da diáspora africana ou mesmo, de forma simples, com suas origens africanas. A apresentação e análise dessas obras foram realizadas de forma cronológica observando-se as biografias, as formações, as temáticas e as pesquisas de interesses dos artistas selecionados, configurando, dessa forma, um corpus de artistas afrodescendentes cujo conjunto de atributos inerentes às suas obras constitui... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This Ph.D. dissertation consists of a several points of investigations, with three main areas of inquiry being especially pertinent. The first is a brief review of the presence of Afro-descendent artists in the history of art in Brazil with the intention of both remembering and revealing people of this category. Moreover, I address how the visual arts produced by Afro-descendents were observed, registered, and documented over two decades by researchers, critics, and historians. The second inquiry proposes a reflection over the exportation and adoption of the term "afro-brazilian" from the United States of America to Brazil in the field of visual studies. The adoption of the terminology "afro-brazilian" has resulted in the categorization of work produced by Brazilians artists of afro-descent into a group based on a shared afro-descendent identity. Furthermore, "afro-brazilian" has been further used for the purposes of labeling thematic research, concepts, aesthetics and/or poetics surrounding the questions related to the history of the afro-descent population. Lastly, the third seeks to present and analyze the production of Brazilian and United States afro-descendent artists who demonstrate interest in creating works which visualize and dialogue with circumstances of the African diaspora or, simply, with their African roots. The presentation and analysis of these works were completed chronologically, with particular attention placed on observing the biographies, themes, and research interests of the selected artists. In this way, I have comprised a body of afro-descendent artists who, due to their related interests and artistic practice, construct an art genre of afro-Brazilians, afro-Americans, or even, African (Complete abstract click electronic access below) / Resumen: Esta investigación doctoral propuesto tiene algunos puntos de investigación, tres de los más relevantes. La primera es una breve reseña de la presencia de artistas de ascendencia africana en la historia de Brasil Arte intención de tanto recordar y revelan personajes y ver cómo se observaron, registran y nombrados durante siglos por los investigadores, críticos e historiadores de las artes visuales producidos por artistas afro-descendientes. La segunda propone una reflexión sobre la aplicación y el uso del término "afro-brasileña" o "afro-brasileña" de Estados Unidos a Brasil en el campo de las Artes Visuales, con fines de categorización de la producción de los artistas afrodescendientes que tienen o investigación no temático, conceptual, estética y / o poética centrada en temas relacionados con la historia del segmento de ascendencia africana de la población. Por último, la tercera se presta a presentar y analizar las producciones de los brasileños y los estadounidenses de artistas afrodescendientes que han mostrado interés en los trabajos elaborados cuyos artes y la estética visual eran en diálogo con los asuntos de la diáspora africana, o incluso, simplemente, con sus orígenes africanos . La presentación y el análisis de estas obras se llevaron a cabo observando cronológicamente las biografías, la capacitación, los temas y los intereses de investigación de los artistas seleccionados,estableciendo así un corpus de artistas de ascendencia africana cuyo conjunto de atributos inherentes a sus obras constituyen de un arte africano brasileño o africano-americano, o, lo que sería más interesante y relevante desde el punto de vista de la discusión iniciada aquí, el arte o afrodiaspórica ascendencia africana (Resumen completo clicar acceso eletrônico abajo) / Doutor

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Comunicação e Expressão, Programa de Pós-graduação em Letras/Inglês e Literatura Correspondente / Made available in DSpace on 2012-10-24T16:35:54Z (GMT). No. of bitstreams: 1 276932.pdf: 624885 bytes, checksum: 5ef322ddea1c9f5b08c1db66c7f8e813 (MD5) / Este trabalho investiga a intertextualidade entre as poesias de Solano Trindade e George Elliot Clarke. O estudo analisa o uso de um eu-enunciador que descreve a luta dos poetas contra a invisibilidade do "eu" negro, a construção de um anti-épico que reconta a história do ponto de vista do negro, a reversão de valores que reafirma a tradição e a cultura negras, e a tentativa de construir uma nova ordem simbólica que se expressa pela ruptura de estereótipos nos textos dos dois autores. A pesquisa revê o discurso da negritude e sua presença na Poesia negra hoje.

231f. / Submitted by Suelen Reis (suelen_suzane@hotmail.com) on 2013-02-20T15:56:39Z No. of bitstreams: 1 Leal.pdf: 1851213 bytes, checksum: ef78c9d9e4e302b109b58c214e5363bf (MD5) / Approved for entry into archive by Fatima Cleômenis Botelho Maria (botelho@ufba.br) on 2013-02-21T13:27:15Z (GMT) No. of bitstreams: 1 Leal.pdf: 1851213 bytes, checksum: ef78c9d9e4e302b109b58c214e5363bf (MD5) / Made available in DSpace on 2013-02-21T13:27:15Z (GMT). No. of bitstreams: 1 Leal.pdf: 1851213 bytes, checksum: ef78c9d9e4e302b109b58c214e5363bf (MD5) Previous issue date: 2011 / Este trabalho tem como objetivo compreender o processo de sociabilidade e engajamento intelectuais em torno da mobilização pela liberdade de culto no Pará de 1938. Nesse momento, o Brasil passava pelo período autoritário do Estado Novo e as práticas culturais de origem africana, especialmente as religiosas, vieram a sofrer perseguição policial. Alguns intelectuais paraenses, em sintonia com as discussões acadêmicas nacionais em torno da experiência negra brasileira, se uniram para e reivindicar um melhor tratamento para os líderes afro-religiosos paraenses. O fundamento da organização intelectual estaria no processo de sociabilidade experimentado por eles no mundo da literatura e da ação política. Frente à continuidade da política de repressão, alguns intelectuais passaram a debater na imprensa a necessidade de liberdade de culto como condição para o crescimento dos estudos sobre o negro no país. Entre os resultados da mobilização intelectual, indicamos o crescente interesse pelo estudo do negro; a participação em eventos nacionais que tratassem da questão; e a inserção da temática da história e cultura negras nas diversas obras destes intelectuais. Entre eles destacaram-se Bruno de Menezes, Gentil Puget, Levi Hall de Moura, Nunes Pereira e Dalcídio Jurandir. / Salvador