Submitted by Hellen Luz (hellencrisluz@gmail.com) on 2017-09-21T19:14:04Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_AvaliacaoInVitro.pdf: 1439306 bytes, checksum: 7f71a06de5db3f1824c5314ed19c43b4 (MD5) / Rejected by Edisangela Bastos (edisangela@ufpa.br), reason: on 2017-10-10T17:00:49Z (GMT) / Submitted by Hellen Luz (hellencrisluz@gmail.com) on 2017-10-17T18:38:23Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_AvaliacaoInVitro.pdf: 1439306 bytes, checksum: 7f71a06de5db3f1824c5314ed19c43b4 (MD5) / Approved for entry into archive by Edisangela Bastos (edisangela@ufpa.br) on 2017-11-24T15:00:16Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_AvaliacaoInVitro.pdf: 1439306 bytes, checksum: 7f71a06de5db3f1824c5314ed19c43b4 (MD5) / Made available in DSpace on 2017-11-24T15:00:16Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_AvaliacaoInVitro.pdf: 1439306 bytes, checksum: 7f71a06de5db3f1824c5314ed19c43b4 (MD5) Previous issue date: 2011-08-12 / CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico / O artesunato representa uma das principais drogas utilizadas como antimaláricos em diversos países. É um composto semi-sintético derivado de artemisinina, substancia extraída da planta chinesa Artemisia annua L. Apesar da ampla utilização do artesunato na terapêutica antimalárica, estudos demonstrando seus efeitos genotóxicos e citotóxicos em cultura de linfócitos humanos são ainda hoje quase inexistentes. Portanto, no presente trabalho, avaliamos os efeitos genotóxicos e citotóxicos do artesunato em cultura de linfócitos humanos. Nossos resultados demonstraram aumento significativo (p<0,05) no número de células apoptóticas dos linfócitos, tanto em 24 quanto em 48 h de tratamento. Desta forma, demonstrou-se em nosso trabalho, que o artesunato é uma droga genotóxica e citotóxica em cultura de linfócitos humanos, nas condições avaliadas. / Artesunate is one of the main drugs used as antimalarials in various countries. It is a semi-synthetic compound from artemisinin, a substance extracted from the Chinese plant Artemisia annua L. Despite the widespread use of antimalarial artesunato in malaria treatment, studies demonstrating its cytotoxic and genotoxic effects in human lymphocyte cultures are almost nonexistent. Therefore, in this study, we evaluated possible cytotoxic and genotoxic effects of artesunate on cultured human lymphocytes. A significant increase (p <0.05) in the rate of DNA damage and micronucleus frequency was observed after artesunato treatment. We also observed that artesunato induces a statically significant increase (p <0,05) in the number of apoptotic cells in both 24 and 48 h of treatment. Thus, we conclude in our work that artesunate is a highly cytotoxic and genotoxic drug in cultured human lymphocytes.

<p>The aim of this study was to investigate the effect the plant matrix and the structure of the flavonoid (i.e. whether aglycone or glycoside) may have on the gastrointestinal uptake and metabolism of luteolin derivatives from Artemisia afra traditional plant medicine. Specifically, how these two factors influenced the intestinal uptake and disposition of luteolin derivatives in pure and in Artemisia afra plant extract forms were to be assessed by investigating the uptake and metabolism of the luteolin derivatives in human intestinal epithelial Caco-2 cells and the perfused rat intestinal loop. To realize this aim, the following were determined: (1) identification and characterization of major luteolin derivatives found in Artemisia afra, (2) the effect of the plant matrix on the uptake of luteolin derivatives in Artemisia afra aqueous-extract forms across the Caco-2 cell monolayer, (3) the effect of the plant matrix on the absorption and metabolism of luteolin derivatives in Artemisia afra aqueous-extract forms in the perfused rat small intestine, (4) the effect of gut contents on the uptake and metabolism of luteolin derivatives in intestinal loop and (5) the metabolic profiles of luteolin derivatives obtained for the pure solutions versus plant aqueous extract solutions in Caco-2 cells and the rat intestine.</p>

Ce travail de recherche porte principalement sur l'analyse d'un corpus d'œuvres d'Artemisia Gentileschi et d'Elisabetta Sirani autour de la thématique des « femmes violentes ». Ces deux artistes italiennes ayant pratiqué la peinture au XVIIe siècle comptent parmi les premières femmes à s'être illustrées dans la représentation de sujets issus de l'histoire biblique et parfois même antique, un genre artistique dominé par leurs collègues masculins. En effet, les récits qu'elles interprètent sont parfois issus de la Bible, comme ceux de Judith ou Yaël, ou encore de l'histoire antique, dans les cas de Timoclée, Lucrèce ou Portia. Or, le thème de la violence au féminin s'avère fortement marqué par une tradition iconographique reflétant les angoisses et préoccupations masculines de l'époque, notamment par une emphase sur le potentiel érotique de ces récits. Ainsi, même les personnages autrefois associés à la chasteté se transforment avec l'ère baroque en véritables guerrières sexuelles. L'étude des œuvres de Gentileschi et de Sirani révèle des écarts iconographiques face à cette tradition, traduisant une prise de position des artistes sur leur sujet. Proposant une vision de la féminité active et parfois même féroce, leur interprétation de ces femmes « violentes » questionne la tradition picturale et ses préjugés sur les femmes. La notion « d'agentivité », prenant sa source dans les écrits de Judith Butler, nous permet alors de mettre en évidence la possibilité d'une resignification de la féminité grâce au travail de ces femmes peintres. À la lumière des approches féministes développées par des historiennes contemporaines comme Griselda Pollock, l'étude des œuvres de ces artistes nous permet d'enrichir notre compréhension de la création au féminin. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : Artemisia Gentileschi, Elisabetta Sirani, histoire des femmes, femmes artistes, violence, peinture biblique, peinture baroque, XVIIe siècle, agentivité, Judith, Yaël, Timoclée, Lucrèce, Portia.

<p>The aim of this study was to investigate the effect the plant matrix and the structure of the flavonoid (i.e. whether aglycone or glycoside) may have on the gastrointestinal uptake and metabolism of luteolin derivatives from Artemisia afra traditional plant medicine. Specifically, how these two factors influenced the intestinal uptake and disposition of luteolin derivatives in pure and in Artemisia afra plant extract forms were to be assessed by investigating the uptake and metabolism of the luteolin derivatives in human intestinal epithelial Caco-2 cells and the perfused rat intestinal loop. To realize this aim, the following were determined: (1) identification and characterization of major luteolin derivatives found in Artemisia afra, (2) the effect of the plant matrix on the uptake of luteolin derivatives in Artemisia afra aqueous-extract forms across the Caco-2 cell monolayer, (3) the effect of the plant matrix on the absorption and metabolism of luteolin derivatives in Artemisia afra aqueous-extract forms in the perfused rat small intestine, (4) the effect of gut contents on the uptake and metabolism of luteolin derivatives in intestinal loop and (5) the metabolic profiles of luteolin derivatives obtained for the pure solutions versus plant aqueous extract solutions in Caco-2 cells and the rat intestine.</p>

El gènere "Artemisia és un dels més grans, pel que fa a nombre d'espècies, de la família de les Asteraceae i és àmpliament distribuït, principalment a l'hemisferi nord, on ocupa hàbitats molt diversos. Algunes de les seves espècies tenen una gran importància econòmica pels seus usos medicinals, alimentaris i ornamentals entre d'altres. El gènere és força conegut des del punt de vista de la seva composició química, però la manca d'estudis biològics generals sobre el gènere i les relacions entre les seves espècies ha sigut la raó per la qual hem dut a terme aquesta tesi doctoral.Aquest estudi comprèn treballs de filogènia molecular basats en la seqüenciació de regions del DNA nuclear i cloroplàstic, que delimiten el subgènere Dracunculus respecte dels altres quatre subgèneres d'Artemisia i estableixen les relaciones entre les espècies que el formen. Les reconstruccions filogenètiques han servit com a marc de discussió per a la resta d'aproximacions, que comprenen estudis cariològics, citogenètics i palinològics i han permès d'establir hipòtesis sobre la colonització del continent sud-americà. S'han realitzat nombrosos recomptes cromosòmicos, molts cops nous per als tàxons concernits, entre ells el primer en el nivell de ploïdia més alt conegut fins ara en el gènere, 16x. Cal destacar a més l'estudi de la grandària del genoma, que estableix un comportament de saturació en l'augment de la quantitat de DNA nuclear en els poliploides i un límit superior per a aquest paràmetre en el gènere. Els estudis sobre les regions 5S i 45S del DNA ribosòmic, duts a terme amb la tècnica d'hibridació in situ fluorescent (FISH), han suggerit l'existència d'un possible model ancestral per al gènere Artemisia quant a la distribució de l'rDNA. L'evolució del genoma d'aquestes espècies ha d'entendre's com el resultat de nombroses reorganitzacions cromosòmiques i de processos de poliploïdització i d'hibridació. També s'ha realitzat una caracterització morfomètrica i microestructural del pol·len del gènere Ajania, així com d'altres Artemisiinae relacionades. Hem confirmat la coexistència dels dos tipus pol·línics descrits a la subtribu, Anthemis i Artemisia, essent el primer el que caracteriza el gènere Ajania. Amb aquestes dades, i en el marc d'una filogènia de la subtribu, podem suggerir que probablement hi ha hagut un canvi del tipus Anthemis (ancestral) al tipus Artemisia (derivat), fet que troba el suport del canvi de la síndrome de pol·linització, d'entomòfila a anemòfila. / The genus Artemisia is one of the largest of the Asteraceae family. It is widely distributed, mainly in the northern hemisphere, where it occupies very different habitats. Some of the species have economic importance for their medicinal uses, as well as for food and ornamental purposes among others. The genus is well known from the standpoint of their chemical composition, but the lack of general biological studies and the poor knowledge of the relationships among its species has been the reason why we have conducted the present thesis.The present study includes a molecular phylogeny based on nuclear and chloroplast DNA regions, which circumscribes the subgenus Dracunculus within the genus Artemisia, studying in depth the relationships between the species of the subgenus. Other phylogenetic reconstructions have been used as frameworks for discussion in different approaches, including karyological, cytogenetic and pollen studies, allowing us to establish, among others, hypotheses about the colonization of South America. Many chromosome counts have been carried out, often related to new taxa, including the first report of the highest ploidy level in the genus to date, 16x (2n = 144 chromosomes). The thesis also includes the study of genome size. The results obtained seem to indicate that the increase of nuclear DNA amount across ploidy levels follows a saturation behaviour according to the Michaelis-Menten function, and a theoretical upper limit for this parameter is hypothesized for the genus. Studies on 5S and 45S regions of ribosomal DNA, carried out with the technique of fluorescent in situ hybridization (FISH) have suggested the existence of different patterns of rDNA distribution in complexes such as the annual representatives of the genus, the subgenus Dracunculus and in the polyploid species on the genus Artemisia. Genome evolution of these species should be understood as the result of numerous chromosomal rearrangements and processes of hybridization and polyploidization. We have also performed a morphometrical and microstructural characterization of the pollen in the genus Ajania and other related Artemisiinae. We have confirmed the coexistence of the two pollen types described in the subtribe, Anthemis and Artemisia, the former being the one that characterizes the genus Ajania. With these data, and in the context of a phylogeny of the subtribe, we suggest that there has probably been a change from the Anthemis type (ancestral) to Artemisia type (derived), a fact which is also supported by the change in the pollination syndrome from entomophily to anemophily.

El genere "Artemisia" L., pertanyent a la família "Asteraceae" Dumortier o "Compositae" Giseke, subfamilia "Asteroideae", tribu "Anthemideae" Cass., subtribu "Chrysanthemineae" Less., és constituït per un nombre d'espècies proper a 300, variable segons els autors, àmpliament repartides per l'hemisferi nord, sobretot a Europa, Àsia, Africà del Nord i Amèrica del Nord i Central, bé que algunes són presents a l'hemisferi sud, per exemple a Xile i en alguns punts del sud del continent africà.Els principals tractadistes acorden al gènere origen eurasiàtic a causa de la major riquesa i diversificació d'espècies existent en aquesta zona. Concretament, el centre primari de diferenciació podria ser l'Àsia central soviètica. KRASHENINNIKOV (1946) estableix 6 centres eurasiàtics d'especiació per al gènere: xino-nipó, angaria, beringià, asiàtic central, asiàtic mitjà i europeo-mediterrani.Es lògic de suposar que les espècies del gènere atenyeren el continent americà des d'Àsia a través de l'estret de Bering; "A. frígida" Willd. i "A. dracunculus" L. es troben naturalment en les dues àrees i foren, doncs, probablement, l'origen de l'expansió americana del grup (MCARTHUR, 1979). Tot amb tot, BEETLE (1979) postula per al gènere origen nord-americà. En el conjunt de la conca mediterrània, el nombre d'espècies d' "Artemisia" decreix de nord a sud i d'oest a est (OUYAHYA, 1980).A la Península Ibèrica, situada a l'extrem oest d'aquesta conca, troben llur límit meridional o occidental alguns taxons (els grups d' "A. chamaemelifolia" i "A. caerulescens",posem per cas) i llur límit nord d'altres (els d'afinitat ibero-nor.d'africana, com el grup d'A. "herba-alba"). I s'hi mantenen interessants endemismes com "A. barrelieri", "A. hispànica" i "A. granatensis".Diverses espècies del gènere tenen aplicació com a estabilitzadores de sòls (MCARTHUR, 1979) i com a fre a processos de desertització (LE HOUËROU, 1979). D'altra banda, tenen gran significació en agroecosistemes des del punt de vista pastoral, sobretot a Amèrica del Nord. (MCARTHUR., 1979) i a l'Africà del Nord (OUYAHYA, 1980). Són d'interès en la fabricació de diversos licors (vermut, absenta) i com a espècies condimentarles (estragó).En el camp medicinal, en podem destacar dos aspectes: per una part, algunes espècies són productores d'al.lèrgies i d'altres generen diverses intoxicacions; i d'altra banda, moltes d'elles tenen compostos amb poderoses accions farmacològiques. Entre aquestes darreres, esmentem la clàssica droga vermífuga coneguda com a santònic, "semen contra" o "semen contra vermes", constituïda pels capítols d' "A. cina" Berg., "A. santonicum" L. i altres espècies orientals relacionades, els principis actius de la qual són lactones sesquiterpèniques. En terres ibèriques, "A. herba-alba" és emprada popularment amb les mateixes finalitats antihelmíntiques.Des del punt de vista d'aplicació i pensant en el nostre àmbit geogràfic, els tres aspectes esmentats tenen interès, tal com es desprèn dels usos populars de les plantes: Diverses espècies, sobretot "A. vulgaris" i "A. absinthium," són utilitzades en l'elaboració de begudes espirituoses. D'altres, bàsicament "A. herba-alba", dominen vastes extensions de territori i són consumides per bestiar divers; podrien ser, doncs, racionalment destinades a pastures.I, finalment, algunes tenen virtuts medicinals. Són, principalment, "A. herba-alba", "A. caerulescens", "A. barrelieri", "A. hispànica", "A. absinthium", "A. arborescens" i "A. granatensis". Material ibèric d'algunes d'aquestes entitats ha estat objecte d'estudis fitoquímics (GONZALEZ & al, 1974; VILLAR & al., 1983) que poden ser la base per a una explotació d'algunes d'elles amb finalitats farmacològiques.L'interès pastoral, alimentari i terapèutic, la situació de la Península Ibèrica i les Illes Balears amb alguns grups crítics o conflictius i el fet que, en el nostre àmbit geogràfic, la darrera monografia del gènere datés dels temps de Moritz Willkomm (1821-1895) ens han menat a intentar dur a terme la revisió de les "Artemisia" ibèricobaleàriques, que comencem per les seccions "Artemisia" i "Seriphidium", des del punt de vista biosistemàtic, sense negligir els mètodes i els criteris de la taxonomia clàssica, però incorporant, a més, noves tècniques que permetin una visió més fina i aprofundida dels problemes.No volem creure que amb el nostre treball hagi quedat completament resolta tota la casuística que afecta els grups estudiats; esperem, això sí, que el que hem fet pugui constituir una aportació sòlida i actualitzada per a continuar avançant en la recerca sobre aquest interessant grup de plantes.

Fundação de Amparo a Pesquisa do Estado de Minas Gerais / Toxoplasmosis is an important zoonotic disease due to ability of its causal agent, Toxoplasma gondii, to infect large number of vertebrates and to be associated with congenital infection or opportunistic disease in immunosuppressed patients. As the traditional treatment has shown adverse effects, low-toxicity compounds including artemisinin and its derivatives have been researched, as well Artemisina annua tea infusion. The use of silicon in the soil of A. annua crops and its role on artemisinin content has not been studied yet. This study aimed to investigate the effects of silicon on A. annua plant physiology and the role of the tea infusion obtained from these plants in the control of T. gondii infection in cell culture. The experimental design was a completely randomized design (CRD), in which A. annua was planted in the soil with five different doses of calcium/magnesium silicate (0, 200, 400, 800 and 1600 kg ha-1) and five replications, and maintained in a greenhouse. Analysis of foliar macronutrients showed a significant increase only for nitrogen, in the presence of the highest dose of silicate in the soil. The foliar micronutrient and Si concentrations as well the plant height were not significantly changed with any silicate doses in the soil. The use of 400 kg ha-1 of silicate induced the highest total glandular trichome area that was also associated with the intact glandular trichomes, as observed by scanning electron microscopy, and with the highest artemisinin content in plant leaves and tea infusion, as determined by thin layer chromatography (TLC) and high performance liquid chromatography (HPLC), respectively. HeLa cell treatments along with or after T. gondii infection, with infusion of A. annua grown in the soil without or with silicate (400 kg ha-1), induced a decrease of parasite proliferation in a dose-dependent manner, as also seen for cell treatment with pure artemisinin. In conclusion, the use of silicon had positive effect on the glandular trichome areas and artemisinin contents, but this outcome was not associated with a better efficacy of A. annua tea infusion on T. gondii replication. These findings suggest that other components rather than artemisinin could be contributing to this effect, such as flavonoids present in its leaves, which may act in synergism with the artemisinin and improve its efficacy. / A toxoplasmose é uma zoonose importante devido à capacidade de seu agente causal, Toxoplasma gondii, de infectar um grande número de vertebrados e ser associada com infecção congênita ou doença oportunista em pacientes imunocomprometidos. O tratamento tradicional mostra efeitos adversos levando à pesquisa de compostos de baixa toxicidade como a artemisinina, seus derivados e a infusão da planta Artemisia annua. A utilização de silício no solo de culturas de A. annua e seu papel no conteúdo de artemisinina ainda não foram estudados. O objetivo deste estudo foi investigar os efeitos do silício sobre a fisiologia da planta A. annua e o papel da infusão destas plantas sobre o controle da infecção de T. gondii em cultura celular. Foi utilizado o delineamento inteiramente ao acaso (DIC), no qual A. annua foi plantada em solo com aplicação de cinco diferentes dosagens de silicato de cálcio/magnésio (0, 200, 400, 800 e 1600 kg ha-1), em cinco repetições e mantida em casa de vegetação. A análise de macronutrientes foliares mostrou um aumento significativo apenas para o nitrogênio, na presença da maior dosagem de silicato no solo. As quantidades de micronutrientes e silício foliares bem como a altura da planta não foram significativamente alteradas em quaisquer dosagens de silicato no solo. A aplicação de 400 kg ha-1 de silicato induziu a maior área de tricomas glandulares totais que foi associada com os tricomas glandulares intactos, como observado por microscopia eletrônica de varredura, e com o mais alto conteúdo de artemisinina nas folhas e na infusão da planta, como determinado por cromatografia em camada fina (TLC) e cromatografia líquida de alta eficiência (HPLC), respectivamente. Os tratamentos de células HeLa, simultaneamente ou após a infecção por T. gondii, com infusão de A. annua cultivada sem ou com silicato (400 kg ha-1) aplicado ao solo, induziram decréscimo dependente da dose na proliferação parasitária, como também verificado para o tratamento das células com artemisinina pura. Em conclusão, o uso de silício teve efeito positivo sobre as áreas de tricomas glandulares e seu conteúdo de artemisinina, mas este resultado não foi associado com melhor eficácia da infusão de A. annua sobre a replicação intracelular de T. gondii. Estes resultados sugerem que outros componentes além da artemisinina poderiam contribuir para este efeito, como os flavonóides presentes nas folhas de A. annua que podem atuar em sinergismo com a artemisinina e melhorar a sua eficácia. / Doutor em Imunologia e Parasitologia Aplicadas

Magister Scientiae (Medical Bioscience) - MSc(MBS) / Endocrine disrupting compounds (EDCs) are exogenous compounds/chemicals which interfere with, or have adverse effects on the production, distribution and function of natural hormones, thereby affecting normal endocrine activity, health and quality of life of both humans and wildlife. The reproductive system is highly susceptible to EDCs due to it being controlled by an array of hormonal signals. The effects of EDCs on the male reproductive system include infertility, decreased sperm count, function and morphology, abnormal development of secondary sex characteristics, reproductive function and sexual behaviour as well as decreased libido. There are various sources by which EDCs enter the environment which include effluents from several industries (mining, agriculture, smelting, hazardous waste sites, manufacturing industries, etc.), sewage treatment effluents, urban and agricultural runoff and effluents which include natural and pharmaceutical chemicals excreted in the urine of humans and domestic livestock, pesticides, polychlorinated biphenyls, dioxins, plasticizers, surfactants, etc. Humans and animals can also be affected by EDCs by consuming food containing endocrine active substances. The growing concern regarding adverse effects due to EDC exposure of humans and wildlife, as well as the increased incidence of EDC contamination has prompted extensive research into the development and validation of screening tests to detect and monitor known EDCs and new substances with endocrine-disrupting capability. These screening tests involve assessing the effect of known and potential EDCs on reproductive function and development as well as hormone production. To assess the effect of EDCs on the reproductive system different methods are employed which include in vitro, in vivo and ex vivo methods. In vitro methods have been suggested as a suitable screening tool for EDC monitoring due to low costs, reduced animal usage, the use of standard and basic equipment as well as the ability to screen a large number of samples with multiple endpoints. Of the available in vitro methods, the minced testes method has been suggested as the most suitable method for screening EDCs and for this reason has been employed in this study. The aim of this study was thus to employ a minced testes method to screen samples for male reproductive toxicity using cell viability and hormone production (testosterone and estradiol) as endpoints.The first objective of this study was to optimize an in vitro testicular cell culture assay by determining both optimal luteinizing hormone (LH)&nbsp; concentration and incubation time needed for testosterone production. Testicular cell cultures were prepared and cells were treated with varying concentrations of LH (10, 1, 0.1, 0.01 and 0 mu/ml) and incubated for 4 hours and 20 hours. Testosterone production was evaluated for each incubation period. Testosterone production was significantly increased for both incubation periods at all LH concentrations tested as compared to the control. For both incubation periods, there was no significant difference in testosterone production between the different LH concentrations tested. From the data obtained, the 4 hour incubation period as well as the LH concentration of 10 mu/ml were selected as optimal for the testicular cell culture assay. The second objective of this study was to determine the effect of Tulbaghia violacea Harv. on the male reproductive system. T. violacea is a plant species indigenous to southern Africa and is used locally as a herbal remedy/medicine to treat several ailments. Cells were treated with varying concentrations of the T. violacea ethanol extract (with/without LH-treatment) and incubated for 4 hours. Hormone production and cell viability were evaluated. The results obtained from this pilot in vitro study demonstrated that the ethanol extract of T.violacea has androgenic properties by significantly increasing LH-induced testosterone production in mouse testes with no significant change in cell viability. The third objective of this study was to assess the effect of Sutherlandia frutescens(L.) R.Br and Artemisia afra Jacq. Ex Willd. on the male reproductive system. S. frutescens and A. afra are also plant species indigenous to southern Africa and used locally as a herbal remedy/medicine to treat several ailments. Ethanol extracts of each plant was prepared and cells were treated with varying concentrations of each extract (0, 156.25, 312.5, 625, 1250,2500 and 5000 &mu;g/ml) with or without LH-treatment and incubated for 4 hours. Cytotoxicity by LDH measurement and hormone production (testosterone and estradiol) were endpoints that were evaluated. The results obtained showed that the ethanol extracts of both plants are not cytotoxic to testicular cells and that A. afra decreases testosterone production at high concentrations. The fourth and final objective of this study was to assess the acute effect of four heavy metals, namely manganese, copper, cadmium and magnesium on the male reproductive system. These heavy metals are used extensively in manufacturing and mining industries. Cells were treated with varying concentrations of each metal salt (200, 100, 50, 25, 12.5, and 6.25 & mu;M) with or without LH-treatment and incubated for 4 hours. Endpoints evaluated included cell viability, testosterone and estradiol production. The results obtained showed that manganese, cadmium and copper are highly toxic to testicular cells in vitro and therefore may potentially cause reproductive toxicity. / South Africa

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

No description available.