Neospora caninum (filo Apicomplexa) é um parasita obrigatório intracelular como todos os membros deste filo, alguns reconhecidos por causarem doenças com impacto relevante na saúde humana (Plasmodium e Toxoplasma) e veterinária (Babesia, Eimeria e Cryptosporidium). Causador da neosporose, N. caninum vem emergindo como um dos maiores causadores de abortos infecciosos em bovinos, levando a consideráveis perdas econômicas na bovinocultura mundial. Devido à sua recente descoberta, o conhecimento sobre diversos processos bioquímicos de N.caninum ainda é limitado, demandando novas pesquisas para a compreensão de seus mecanismos de sobrevivência e consequente identificação de alvos para intervenção terapêutica. O processo de invasão celular é bastante investigado em pesquisas envolvendo apicomplexas, uma vez que a sobrevivência desses parasitas depende do sucesso de sua entrada na célula hospedeira. Proteínas secretadas de organelas filo-específicas (micronemas, roptrias e grânulos densos) estão intimamente envolvidas com a invasão celular. Elas são responsáveis pela interação inicial com a célula hospedeira, participam da junção de movimento formada no momento da invasão, e contribuem para a estabilização do vacúolo parasitóforo. Neste trabalho as proteínas secretadas por taquizoítas de N. caninum foram investigadas de duas formas: (1) por caracterização molecular de proteínas com domínio Apple; e (2) por estudo do secretoma do parasita. Os domínios proteicos do tipo Apple são caracterizados pela capacidade de interação proteína-proteína e proteína-carboidrato, e estão presentes em algumas proteínas micronêmicas com propriedades adesivas. Neste trabalho três proteínas de N. caninum contendo domínios Apple foram caracterizadas: MIC17A, MIC17B e MIC17C. A análise das sequências proteicas e das estruturas dos domínios Apple, obtidas por modelagem molecular, mostraram alta identidade sequencial e estrutural entre MIC17A e MIC17C. Apesar de ser paráloga às outras duas, MIC17B apresenta diferenças importantes em sua sequência e estrutura. Para MIC17B e MIC17C foram realizados experimentos de detecção das proteínas nativas nos extratos total e secretado do taquizoíta que sugerem diferentes formas de processamento entre essas proteínas no parasita. Para MIC17B foi confirmada a localização em micronemas, num padrão diferente do observado para MIC17C. Os ensaios de invasão combinados aos de localização indicam que estas proteínas estejam relacionadas ao processo de invasão celular, porém, suas funções permanecem desconhecidas. O secretoma é o conjunto de proteínas secretadas pelo parasita e, para explorar a composição deste extrato (ESA) no taquizoíta de N. caninum, duas abordagens complementares foram utilizadas. Na primeira abordagem foram identificadas as proteínas presentes no ESA por espectrometria de massas. Na segunda abordagem realizou-se uma ii quantificação relativa das proteínas, marcadas por dois isótopos, nos extratos totais de taquizoítas submetidos ou não ao estímulo secretório. O resultado esperado seria com as proteínas secretadas diminuídas no parasita estimulado. Em ambas as abordagens foram utilizadas técnicas de espectrometria de massas de alta resolução (nanoLC-MS/MS), o que resultou num alto número de identificações; 615 proteínas no ESA e 2011 proteínas quantificadas. A comparação das duas abordagens permitiu o reconhecimento de proteínas com maior probabilidade de secreção. Uma rede de interação entre as proteínas diferencialmente expressas foi predita, gerando resultados que, associados às informações sobre as proteínas aumentadas, permitiram uma investigação sobre proteínas potencialmente envolvidas com a regulação do metabolismo relacionado à secreção. Os resultados obtidos por ambos os estudos aqui demonstrados somam conhecimento acerca do parasita N. caninum e demonstram ser úteis para guiar a busca e seleção de alvos a serem investigados para o desenvolvimento de terapêutica contra a neosporose. / Neospora caninum (Apicomplexa phylum) is an obligatory intracellular parasite like all members from this phylum, some causing diseases with relevant impact on human (Plasmodium and Toxoplasma) and veterinary (Babesia, Eimeria and Cryptosporidium) health. Causative agent of neosporosis, N. caninum has emerged as one of the leading causes of infectious abortion in cattle, generating huge economical losses in worldwide livestock. Due to its recent discovery, knowledge of N. caninum biochemical processes remains scarce, demanding new research for comprehending its survival mechanisms and, consequently, identifying new targets for therapeutic intervention. The invasion process has often been investigated in apicomplexans since their survival depends on the success of their entry into the host cell. Proteins secreted from phylum-specific organelles (micronemes, rhoptries and dense granules) are deeply involved with invasion. They are responsible for the initial interaction with the host cell; participate of the moving junction formed in the moment of invasion; and contribute for the stabilization of the parasitophorus vacuole. In this study, the proteins secreted by N. caninum tachyzoites were investigated in two ways: (1) the molecular characterization of Apple domaincontaining proteins; and (2) exploring the parasite secretome. The Apple protein domains are characterized by the ability to interact as protein-protein and proteincarbohydrate, and are present in some microneme proteins with adhesive properties. Here three N. caninum proteins containing Apple domains were characterized: MIC17A, MIC17B and MIC17C. Analyses of the Apple domains sequences and structures, obtained by molecular modeling, revealed high sequential and structural identities between MIC17A and MIC17C. Although being a paralog of the other two proteins, MIC17B presents significant differences in its sequence and structure. Experiments were performed for native MIC17B and MIC17C detection in the total and secreted tachyzoite extracts, suggesting different processing forms for these proteins in the parasite. For MIC17B, the microneme localization was confirmed, differently from the pattern observed for MIC17C. Invasion and localization assays indicated that these proteins are related to the cell invasion process; nevertheless, their functions remain unknown. The secretome is the set of proteins secreted by the parasite and, to explore this extract (ESA) composition in N. caninum, two complementary approaches were used. Firstly proteins present in ESA were identified by mass spectrometry. In the second approach, a relative quantification was performed on the proteomes of ethanol stimulated/non stimulated tachyzoites, expecting that the secreted proteins would be down regulated at the stimulated parasite. Both approaches were performed with high resolution mass spectrometry techniques (nanoLC-MS/MS), reaching a high number of identifications: 615 proteins iv in ESA and 2011 quantified proteins. The comparison between both approaches allowed the recognition of the most likely secreted proteins. An interaction network was predicted, involving the differentially expressed proteins. These results, associated with the information of up regulated proteins, allowed the investigation of proteins potentially involved with the secretion metabolism regulation. The findings from our two studies add up knowledge about N. caninum and demonstrate to be useful in guiding the search and selection for new targets for therapeutic development against neosporosis.

O carcinoma epidermóide representa mais de 90% das neoplasias malignas de cabeça e pescoço, apresentando taxas elevadas de morbi-mortalidade, porém pouco se sabe sobre as vias de sinalização que estão envolvidas na progressão tumoral. Têm sido relatado na literatura, que alguns estímulos podem ativar a holoenzima PI3K que, por sua vez, desencadeia um processo que induz a fosforilação da proteína Akt (pAkt) que leva a ativação e a translocação do NF-B do citoplasma para o núcleo, onde ocorre a transcrição de genes envolvidos na proliferação e invasão celular. Assim, esse estudo analisou, através dos métodos de Imunofluorescência e Western Blot, a expressão das proteínas pAkt, NF-B e Ciclina D1 em três linhagens de células de carcinoma epidermóide de cabeça e pescoço (HN6, HN30 e HN31) submetidas a cultivo tridimensional e ensaio de invasão (gerando clones invasivos HN6.1, HN30.1 e HN31.1), ambos realizados com Matrigel®. O pAkt apresentou marcação citoplasmática e nuclear nas linhagens celulares HN6, HN30, HN6.1 e na HN30 submetida ao cultivo tridimensional, todavia, as linhagens celulares HN31, HN30.1, HN31.1 e HN6/HN31 cultivadas tridimensionalmente, apresentaram positividade predominantemente nuclear. No caso do NF-B, a localização foi marcadamente citoplasmática em todas as linhagens celulares cultivadas bi ou tridimensionalmente, porém, com exceção da HN31.1, o padrão de marcação foi citoplasmático e nuclear nos clones invasivos. Por fim, a Ciclina D1 exibiu imunopositividade apenas nuclear. A técnica de Western Blot mostrou diminuição nos níveis de expressão das proteínas analisadas quando as células foram cultivadas em Matrigel®, sendo, na maioria das vezes, essa redução estatisticamente significante, exceto no caso da linhagem celular HN6, que apresentou um aumento significativo de Ciclina D1. Os clones invasivos HN6.1 e HN30.1 exibiram elevação significativa dos níveis de expressão de pAkt e NF-B porém, a HN31.1 apresentou aumento de pAkt e discreta diminuição de NF-B, mas ambos os valores não estatisticamente significantes. Em relação à Ciclina D1, houve um aumento dos seus níveis em todas as linhagens invasivas, sendo que apenas na HN6.1 foi estatisticamente significante. Esses resultados mostraram que, nas linhagens celulares avaliadas, quando cultivadas em ambiente tridimensional, a significativa redução dos níveis de expressão de proteínas da via de sinalização PI3K ocorreu devido a uma possível fase adaptativa dessas células ao Matrigel® que seria seguida provavelmente por uma etapa de aumento do potencial proliferativo e posterior transdiferenciação de algumas células para ganho de fenótipo mais agressivo. Além disso, este estudo mostrou a participação da via de sinalização Akt/NF-B/Ciclina D1 no processo de invasão das células de carcinoma epidermóide de cabeça e pescoço (HN6.1 e HN30.1). / Squamous cell carcinoma represents more than 90% of the head and neck malignant tumors, with high mortality rates. Nevertheless, the knowledge about signaling pathways involved in tumor progression remains unclear. The relationship between pAkt and NF-B is well established in carcinogenesis. It is known that the activation of PI3K can be induced by some factors what leads to Akt phosphorilation (pAkt). This further event starts an activation cascade that induces NF-B translocation from the cytoplasm into the nucleus where the transcription of genes enrolled in cellular proliferation and invasion will be done. Therefore, this study analyzed the status of pAkt, NF-B and Cyclin D1 proteins by Immunofluorescence and Western Blot methods in three head and neck squamous cell carcinoma cell lines (HN6, HN30 and HN31) submitted to three-dimensional culture model and an in vitro invasion assay (invasive clones HN6.1, HN30.1 e HN31.1), both with Matrigel®. pAkt expression was detected in cytoplasm and nucleus in HN6, HN30, HN6.1 and HN30 cultured with Matrigel®, however, HN31, HN30.1, HN31.1 cell lines and HN6/HN31 submitted to three-dimensional culture model showed nuclear expression. NF-B localization was strongly cytoplasmatic in all cell lines cultured with or without Matrigel®, but, regarding HN31.1, NF-B protein expression was nuclear and cytoplasmatic in the invasive clones. Cyclin D1 was nuclear in all cell lines analyzed. Western blot assays showed a decrease in pAkt, NF-B and Cyclin D1 expression levels in all cells lines in three-dimensional culture model, most of them statistically significant, but It was detected a considerable increase in Cyclin D1 expression in HN6 cultured in threedimensional model. Moreover, HN6.1 and HN30.1 showed a significant enhance in pAkt and NF-B levels but, HN31.1 demonstrated a raise in pAkt and a slight decline in NF-B, both were not statistically significant. Finally, an increase in Cyclin D1 expression levels was illustrated in all cell lines but, only HN6.1 showed a statistic signal. These results suggest that, in the cell lines studied, when cultured in threedimensional model, a noteworthy reduction in expression levels of PI3K signaling pathway proteins happened for the reason that a possibly adaptation phase of these cells to Matrigel® was occurring, in the first moment, but it would be probably followed by an increase proliferative potential stage and subsequent transdifferentiation of some cells that could show, consequently, a more aggressive phenotype. At last, this study revealed the participation of Akt/NF-B/Cyclin D1 signaling pathway in invasion process of head and neck squamous cell carcinoma (HN6.1 and HN30.1).

O presente trabalho teve como objetivo o estudo da variabilidade genética e dos fatores de virulência de isolados de U. diversum. As cepas foram submetidas a sequenciamento dos genes da urease e 16S rRNA e a testes para verificar os fatores de virulência: cápsula, fosfolipase C, IgAse e adesão e invasão. A análise do sequênciamento parcial do gene 16S rRNA resultou na presença de polimorfismos em 44 posições da seqüência, que diferenciou as amostras em sete grupos. Em relação aos fatores de virulência, os dados mostraram que as cepas estudadas apresentaram uma camada densa ao redor da membrana celular dos microrganismos e atividade de fosfolipase C. No entanto, não foi observado a atividade de IgAse nas cepas. Em relação a atividade de invasão, observou-se que os ureaplasma estudados puderam ser visualizados no interior de células Hep-2 com apenas um minutos de infecção, sendo observados em uma região perinuclear, mas não no interior do núcleo. Além disto, pode verificar que entre 1% a 10% dos ureaplasmas estudos penetraram na célula pelo teste da gentamicina. / The aim of the present study was the study of genetic variability and virulence factors of U. diversum clinical isolates. The strains were submitted to sequencing for 16S rRNA and urease genes. Moreover, the strains were analyzed to the virulence factors: capsule, phospholipase C, IgA protease and adhesion and invasion into Hep-2 cells. The sequencing of parcial 16S rRNA gene showed polymorphic patterns into 44 positions. These polymorphisms clustered the strains in seven groups. For the virulence factors, ureaplasma cells showed a dense-stained external capsule-like structure surrounding the cell membrane. A high level of phospholipase C activity was also detected in 31 studied ureaplasma. However, no strains showed IgA protease activity. For the invasion assay, the isolates and strains used were detected inside the cells after infection of one minute. The invasions of the ureaplasmas surrounded the nuclear region but were not observed inside the nuclei. The gentamicin invasion assay detected that 1% to 10% of studied ureaplasmas were inside the infected cells.

<p>Имајући&nbsp; у&nbsp; виду&nbsp; значај&nbsp; површинских&nbsp; вода&nbsp; у продору&nbsp; и&nbsp; ширењу&nbsp; страних&nbsp; инвазивних врста,&nbsp; циљеви&nbsp; овог&nbsp; рада&nbsp; били&nbsp; су&nbsp; да&nbsp; се представи&nbsp; актуелно&nbsp; стање&nbsp; присуства&nbsp; и дистрибуције&nbsp; акватичних&nbsp; инвазивних биљних&nbsp; врста&nbsp; у&nbsp; површинским&nbsp; копненим водама,&nbsp; анализира&nbsp; степен&nbsp; инвазије рипаријалних&nbsp; зона&nbsp; на&nbsp; подручју&nbsp; Србије, одреди&nbsp; везаност&nbsp; анализираних&nbsp; инвазивних<br />врста&nbsp; за&nbsp; поједине&nbsp; типове&nbsp; станишта&nbsp; у рипаријалу река и канала и анализира утицај различитих&nbsp; станишних&nbsp; и&nbsp; антропогених фактора&nbsp; на&nbsp; присуство&nbsp; и&nbsp; абунданцу&nbsp; 26 одабраних&nbsp; инвазивних&nbsp; таксона.&nbsp; Теренска истраживања&nbsp; вршена&nbsp; су&nbsp; у&nbsp; периоду&nbsp; од&nbsp; 2013. до&nbsp; 2016.&nbsp; године.&nbsp; За&nbsp; потребе&nbsp; овог&nbsp; рада анализирано је 250 локалитета, од чега 217 у рипаријалу&nbsp; 39&nbsp; река&nbsp; и&nbsp; 33&nbsp; у&nbsp; рипаријалу&nbsp; шест<br />деоница&nbsp; канала&nbsp; хидросистема&nbsp; Дунав-Тиса-Дунав.&nbsp; Уз&nbsp; податке&nbsp; о&nbsp; бројности&nbsp; и<br />покровности&nbsp; заступљених&nbsp; биљних&nbsp; врста, сакупљани&nbsp; су&nbsp; и&nbsp; подаци&nbsp; о&nbsp; типу&nbsp; станишта&nbsp; (у складу&nbsp; са&nbsp; EUNIS&nbsp; класификацијом), релевантним&nbsp; физичким&nbsp; и<br />хидроморфолошким&nbsp; карактеристикама истраживаних&nbsp; водотокова&nbsp; и&nbsp; доминантним антропогеним&nbsp; утицајима&nbsp; на&nbsp; истраживаном локалитету&nbsp; (у&nbsp; складу&nbsp; са&nbsp; стандардним протоколом&nbsp; RHS&nbsp; методе).&nbsp; Статистичка обрада&nbsp; података&nbsp; вршена&nbsp; је&nbsp; у&nbsp; софтверу CANOCO&nbsp; 5.0,&nbsp; применом&nbsp; анализе&nbsp; главних компоненти&nbsp; (РСА),&nbsp; канонијскe коресподентнe&nbsp; анализе&nbsp; (CCA)&nbsp; и&nbsp; анализе редундантности&nbsp; (RDA).&nbsp; На&nbsp; територији Србије&nbsp; забележено&nbsp; је&nbsp; присуство&nbsp; осам акватичних&nbsp; инвазивних&nbsp; биљних&nbsp; врстаПрема&nbsp; броју&nbsp; налаза&nbsp; истичу&nbsp; се&nbsp; врсте Vallisneria spiralis, Azolla filiculoides и Elodea&nbsp; nuttallii.&nbsp; Примарно су заступљене у текућим,<br />у односу на стајаће воде, при чему се мрежа&nbsp; канала&nbsp; ХС&nbsp; ДТД&nbsp; и&nbsp; речни&nbsp; токови&nbsp; који&nbsp; припадају&nbsp; сливу&nbsp; Дунава&nbsp; могу&nbsp; сматрати&nbsp; основним&nbsp; акватичним&nbsp; коридорима&nbsp; њиховог&nbsp; ширења.&nbsp; Од&nbsp; 26&nbsp; таксона&nbsp; инвазивних&nbsp; биљака&nbsp; чије&nbsp; је&nbsp; присуство&nbsp; праћено&nbsp; и&nbsp; анализирано&nbsp; у&nbsp; рипаријалним&nbsp; подручјима,&nbsp; таксони&nbsp; са<br />највећим&nbsp; бројем&nbsp; налаза&nbsp; су&nbsp;<em> Xanthium&nbsp; strumarium</em>&nbsp; subsp.&nbsp; <em>italicum,&nbsp; Amorpha</em> <em>fruticosa, Erigeron&nbsp; canadensis,&nbsp; Robinia&nbsp; pseudoacacia&nbsp; и&nbsp; Echinochloa&nbsp; crus-galli.</em>&nbsp; Речни&nbsp; сливови Дунава,&nbsp; Јужне&nbsp; Мораве,&nbsp; Западне&nbsp; Мораве&nbsp; и&nbsp; Тимока&nbsp; истичу&nbsp; се&nbsp; по&nbsp; заступљености&nbsp; истраживаних таксона. На основу података о дистрибуцији,&nbsp; бројности&nbsp; и&nbsp; покровности&nbsp; анализираних&nbsp; таксона&nbsp; сливови&nbsp; Дунава, Колубаре и Западне Мораве издвојили су се&nbsp; као&nbsp; коридори&nbsp; ширења&nbsp; највећег&nbsp; броја<br />истраживаних&nbsp; таксона.&nbsp; Четири&nbsp; типа&nbsp; станишта&nbsp; издвојила&nbsp; су&nbsp; се&nbsp; према<br />заступљености&nbsp; инвазивних&nbsp; биљних&nbsp; врста.&nbsp; Таксони који су забележени у највећем броју&nbsp; типова&nbsp; станишта&nbsp; су:&nbsp; <em>Amorpha&nbsp; fruticosa, Erigeron&nbsp; canadensis,&nbsp;</em> <em>Robinia&nbsp; pseudoacacia, Echinochloa crus-galli&nbsp;</em> и&nbsp; <em>Xanthium strumarium subsp</em>.&nbsp; <em>italicum.</em>&nbsp; Као&nbsp; резултат&nbsp; нумеричких&nbsp; анализа&nbsp; издвојени&nbsp; су&nbsp; физички&nbsp; и<br />хидроморфолошки параметри истраживаних&nbsp; водотокова&nbsp; и&nbsp; доминантни&nbsp; антропогени&nbsp; утицаји који на истраживаном локалитетима утичу&nbsp; на&nbsp; присуство&nbsp; и&nbsp; абунданцу&nbsp; анализираних&nbsp; таксона.&nbsp; У&nbsp; условима&nbsp; глобалних&nbsp; климатских&nbsp; промена&nbsp; може&nbsp; се&nbsp; очекивати да ће се&nbsp; у наредном периоду под снажним&nbsp; притиском&nbsp; ширења&nbsp; и&nbsp; доминације&nbsp; инвазивних врста наћи сливови Саве, Велике Мораве&nbsp; и&nbsp; Јужне&nbsp; Мораве.&nbsp; У&nbsp; рипаријалним областима на југозападу наше земље (долине Лима,&nbsp; Ибра&nbsp; и&nbsp; њихових&nbsp; притока)&nbsp; као&nbsp; и&nbsp; рипаријалним&nbsp; зонама&nbsp; планинских&nbsp; и високопланинских&nbsp; области&nbsp; такође&nbsp; је очекивано&nbsp; да&nbsp; ће&nbsp; доћи&nbsp; до&nbsp; повећања&nbsp; броја присутних&nbsp; инвазивних&nbsp; врста&nbsp; и&nbsp; њиховог даљег ширења.</p> / <p>Imajući&nbsp; u&nbsp; vidu&nbsp; značaj&nbsp; površinskih&nbsp; voda&nbsp; u prodoru&nbsp; i&nbsp; širenju&nbsp; stranih&nbsp; invazivnih vrsta,&nbsp; ciljevi&nbsp; ovog&nbsp; rada&nbsp; bili&nbsp; su&nbsp; da&nbsp; se predstavi&nbsp; aktuelno&nbsp; stanje&nbsp; prisustva&nbsp; i distribucije&nbsp; akvatičnih&nbsp; invazivnih biljnih&nbsp; vrsta&nbsp; u&nbsp; površinskim&nbsp; kopnenim vodama,&nbsp; analizira&nbsp; stepen&nbsp; invazije riparijalnih&nbsp; zona&nbsp; na&nbsp; području&nbsp; Srbije, odredi&nbsp; vezanost&nbsp; analiziranih&nbsp; invazivnih<br />vrsta&nbsp; za&nbsp; pojedine&nbsp; tipove&nbsp; staništa&nbsp; u riparijalu reka i kanala i analizira uticaj različitih&nbsp; stanišnih&nbsp; i&nbsp; antropogenih faktora&nbsp; na&nbsp; prisustvo&nbsp; i&nbsp; abundancu&nbsp; 26 odabranih&nbsp; invazivnih&nbsp; taksona.&nbsp; Terenska istraživanja&nbsp; vršena&nbsp; su&nbsp; u&nbsp; periodu&nbsp; od&nbsp; 2013. do&nbsp; 2016.&nbsp; godine.&nbsp; Za&nbsp; potrebe&nbsp; ovog&nbsp; rada analizirano je 250 lokaliteta, od čega 217 u riparijalu&nbsp; 39&nbsp; reka&nbsp; i&nbsp; 33&nbsp; u&nbsp; riparijalu&nbsp; šest<br />deonica&nbsp; kanala&nbsp; hidrosistema&nbsp; Dunav-Tisa-Dunav.&nbsp; Uz&nbsp; podatke&nbsp; o&nbsp; brojnosti&nbsp; i<br />pokrovnosti&nbsp; zastupljenih&nbsp; biljnih&nbsp; vrsta, sakupljani&nbsp; su&nbsp; i&nbsp; podaci&nbsp; o&nbsp; tipu&nbsp; staništa&nbsp; (u skladu&nbsp; sa&nbsp; EUNIS&nbsp; klasifikacijom), relevantnim&nbsp; fizičkim&nbsp; i<br />hidromorfološkim&nbsp; karakteristikama istraživanih&nbsp; vodotokova&nbsp; i&nbsp; dominantnim antropogenim&nbsp; uticajima&nbsp; na&nbsp; istraživanom lokalitetu&nbsp; (u&nbsp; skladu&nbsp; sa&nbsp; standardnim protokolom&nbsp; RHS&nbsp; metode).&nbsp; Statistička obrada&nbsp; podataka&nbsp; vršena&nbsp; je&nbsp; u&nbsp; softveru CANOCO&nbsp; 5.0,&nbsp; primenom&nbsp; analize&nbsp; glavnih komponenti&nbsp; (RSA),&nbsp; kanonijske korespodentne&nbsp; analize&nbsp; (CCA)&nbsp; i&nbsp; analize redundantnosti&nbsp; (RDA).&nbsp; Na&nbsp; teritoriji Srbije&nbsp; zabeleženo&nbsp; je&nbsp; prisustvo&nbsp; osam akvatičnih&nbsp; invazivnih&nbsp; biljnih&nbsp; vrstaPrema&nbsp; broju&nbsp; nalaza&nbsp; ističu&nbsp; se&nbsp; vrste Vallisneria spiralis, Azolla filiculoides i Elodea&nbsp; nuttallii.&nbsp; Primarno su zastupljene u tekućim,<br />u odnosu na stajaće vode, pri čemu se mreža&nbsp; kanala&nbsp; HS&nbsp; DTD&nbsp; i&nbsp; rečni&nbsp; tokovi&nbsp; koji&nbsp; pripadaju&nbsp; slivu&nbsp; Dunava&nbsp; mogu&nbsp; smatrati&nbsp; osnovnim&nbsp; akvatičnim&nbsp; koridorima&nbsp; njihovog&nbsp; širenja.&nbsp; Od&nbsp; 26&nbsp; taksona&nbsp; invazivnih&nbsp; biljaka&nbsp; čije&nbsp; je&nbsp; prisustvo&nbsp; praćeno&nbsp; i&nbsp; analizirano&nbsp; u&nbsp; riparijalnim&nbsp; područjima,&nbsp; taksoni&nbsp; sa<br />najvećim&nbsp; brojem&nbsp; nalaza&nbsp; su&nbsp;<em> Xanthium&nbsp; strumarium</em>&nbsp; subsp.&nbsp; <em>italicum,&nbsp; Amorpha</em> <em>fruticosa, Erigeron&nbsp; canadensis,&nbsp; Robinia&nbsp; pseudoacacia&nbsp; i&nbsp; Echinochloa&nbsp; crus-galli.</em>&nbsp; Rečni&nbsp; slivovi Dunava,&nbsp; Južne&nbsp; Morave,&nbsp; Zapadne&nbsp; Morave&nbsp; i&nbsp; Timoka&nbsp; ističu&nbsp; se&nbsp; po&nbsp; zastupljenosti&nbsp; istraživanih taksona. Na osnovu podataka o distribuciji,&nbsp; brojnosti&nbsp; i&nbsp; pokrovnosti&nbsp; analiziranih&nbsp; taksona&nbsp; slivovi&nbsp; Dunava, Kolubare i Zapadne Morave izdvojili su se&nbsp; kao&nbsp; koridori&nbsp; širenja&nbsp; najvećeg&nbsp; broja<br />istraživanih&nbsp; taksona.&nbsp; Četiri&nbsp; tipa&nbsp; staništa&nbsp; izdvojila&nbsp; su&nbsp; se&nbsp; prema<br />zastupljenosti&nbsp; invazivnih&nbsp; biljnih&nbsp; vrsta.&nbsp; Taksoni koji su zabeleženi u najvećem broju&nbsp; tipova&nbsp; staništa&nbsp; su:&nbsp; <em>Amorpha&nbsp; fruticosa, Erigeron&nbsp; canadensis,&nbsp;</em> <em>Robinia&nbsp; pseudoacacia, Echinochloa crus-galli&nbsp;</em> i&nbsp; <em>Xanthium strumarium subsp</em>.&nbsp; <em>italicum.</em>&nbsp; Kao&nbsp; rezultat&nbsp; numeričkih&nbsp; analiza&nbsp; izdvojeni&nbsp; su&nbsp; fizički&nbsp; i<br />hidromorfološki parametri istraživanih&nbsp; vodotokova&nbsp; i&nbsp; dominantni&nbsp; antropogeni&nbsp; uticaji koji na istraživanom lokalitetima utiču&nbsp; na&nbsp; prisustvo&nbsp; i&nbsp; abundancu&nbsp; analiziranih&nbsp; taksona.&nbsp; U&nbsp; uslovima&nbsp; globalnih&nbsp; klimatskih&nbsp; promena&nbsp; može&nbsp; se&nbsp; očekivati da će se&nbsp; u narednom periodu pod snažnim&nbsp; pritiskom&nbsp; širenja&nbsp; i&nbsp; dominacije&nbsp; invazivnih vrsta naći slivovi Save, Velike Morave&nbsp; i&nbsp; Južne&nbsp; Morave.&nbsp; U&nbsp; riparijalnim oblastima na jugozapadu naše zemlje (doline Lima,&nbsp; Ibra&nbsp; i&nbsp; njihovih&nbsp; pritoka)&nbsp; kao&nbsp; i&nbsp; riparijalnim&nbsp; zonama&nbsp; planinskih&nbsp; i visokoplaninskih&nbsp; oblasti&nbsp; takođe&nbsp; je očekivano&nbsp; da&nbsp; će&nbsp; doći&nbsp; do&nbsp; povećanja&nbsp; broja prisutnih&nbsp; invazivnih&nbsp; vrsta&nbsp; i&nbsp; njihovog daljeg širenja.</p> / <p>Bearing&nbsp; in&nbsp; mind&nbsp; the&nbsp; significance&nbsp; of&nbsp; inland surface waters for the introduction and spread of invasive&nbsp; alien&nbsp; species&nbsp; (IAS),&nbsp; the&nbsp; aims&nbsp; of&nbsp; this research&nbsp; were&nbsp; to&nbsp; present&nbsp; the&nbsp; contemporary records&nbsp; of&nbsp; aquatic&nbsp; invasive&nbsp; plant&nbsp; species&nbsp; in surface&nbsp; waters,&nbsp; analyse&nbsp; the&nbsp; level&nbsp; of&nbsp; invasion&nbsp; of riparian&nbsp; areas&nbsp; in&nbsp; Serbia,&nbsp; determine&nbsp; the&nbsp; habitat preferences&nbsp; of&nbsp; the&nbsp; analysed&nbsp; IAS&nbsp; and&nbsp; determine the effects of different habitat characteristics and anthropogenic&nbsp; influences&nbsp; on&nbsp; the&nbsp; presence&nbsp; and bundance&nbsp; of&nbsp; the&nbsp; 26&nbsp; analysed&nbsp; invasive&nbsp; plants. Field&nbsp; research&nbsp; was&nbsp; conducted&nbsp; during&nbsp; the&nbsp; 2013-2016&nbsp; period.&nbsp; A&nbsp; total&nbsp; of&nbsp; 250&nbsp; field&nbsp; sites&nbsp; were analysed&nbsp; as&nbsp; part&nbsp; of&nbsp; this&nbsp; research,&nbsp; 217&nbsp; in&nbsp; the riparian zones of 39 rivers and 33 in the riparian zones&nbsp;&nbsp;&nbsp; of&nbsp; six&nbsp; canal&nbsp; sections&nbsp; of&nbsp; the&nbsp; hydrosystem Danube-Tisa-Danube&nbsp; (HS&nbsp; DTD).&nbsp; In&nbsp; addition&nbsp; to data on the cover and abundance of the analysed plant species, data on habitat type (following the EUNIS&nbsp; classification),&nbsp; relevant&nbsp; physical&nbsp; and hydromorhological&nbsp; parameters&nbsp; of&nbsp; the&nbsp; studied watercourses&nbsp; and&nbsp; dominant&nbsp; anthropogenic influences an analysed field sites were recorded (following&nbsp; the&nbsp; standard&nbsp; RHS&nbsp; protocol). Statistical&nbsp; data&nbsp; analysis&nbsp; was&nbsp; done&nbsp; in&nbsp; CANOCO 5.0&nbsp;&nbsp; software,&nbsp; using&nbsp; the&nbsp; principal&nbsp; component analysis&nbsp; (PCA),&nbsp; canonical&nbsp; correspondence analysis (CCA) and redundancy analysis (RDA). Eight&nbsp; aquatic&nbsp; invasive&nbsp; plant&nbsp; species&nbsp; were recorded for the territory of Serbia. Species with the highest number of records were:&nbsp; Vallisneria spiralis,&nbsp; Azolla filiculoides&nbsp; and&nbsp; Elodea nuttallii. They&nbsp; are&nbsp; primarily&nbsp; present&nbsp; in&nbsp; running,&nbsp; in comparison&nbsp; with&nbsp; standing&nbsp; waters,&nbsp; and&nbsp; the&nbsp; canal network&nbsp; of&nbsp; the&nbsp; HS&nbsp; DTD&nbsp; and&nbsp; rivers&nbsp; of&nbsp; the Danube catchment area are considered to be their main&nbsp; aquatic&nbsp; corridor&nbsp; of&nbsp; spread.&nbsp; Of&nbsp; the&nbsp; 26 invasive plant taxa whose presence&nbsp; was recorded and&nbsp; analysed&nbsp; in&nbsp; the&nbsp; riparian&nbsp; areas&nbsp; of&nbsp; Serbia,Xanthium strumarium&nbsp; subsp.&nbsp; italicum,&nbsp; Amorpha fruticosa,&nbsp; Erigeron&nbsp; canadensis,&nbsp; Robinia pseudoacacia&nbsp; and&nbsp; Echinochloa&nbsp; crus-&nbsp; galli&nbsp; were taxa&nbsp; with&nbsp; the&nbsp; highest&nbsp; number&nbsp; of&nbsp; records.Catchment&nbsp; areas&nbsp; of&nbsp; the&nbsp; Danube,&nbsp; Južna&nbsp; Morava, Zapadna&nbsp; Morava&nbsp; and&nbsp; Timok&nbsp; rivers&nbsp; were characterised&nbsp; by&nbsp; the&nbsp; highest&nbsp; levels&nbsp; of&nbsp; invasion. Based&nbsp; on&nbsp; their&nbsp; distribution&nbsp; data,&nbsp; cover&nbsp; and abundance of the analysed taxa, catchment areas of&nbsp; the&nbsp; Danube,&nbsp; Kolubara&nbsp; and&nbsp; Zapadna&nbsp; Morava rivers&nbsp; are&nbsp; highlighted&nbsp; as&nbsp; the&nbsp; main&nbsp; corridors&nbsp; of spread for the majority of the studied IAS. Four habitat&nbsp; types&nbsp; stand&nbsp; out&nbsp; by&nbsp; the&nbsp; number&nbsp; of analysed IAS. Taxa which were recorded in the highest&nbsp; number&nbsp; of&nbsp; habitat&nbsp; types&nbsp; are:&nbsp; Amorpha fruticosa,&nbsp; Erigeron&nbsp; canadensis,&nbsp; Robinia pseudoacacia,&nbsp; Echinochloa&nbsp; crus-galli&nbsp; and Xanthium strumarium subsp. italicum.&nbsp; A number of&nbsp; physical&nbsp; and&nbsp; hydromorphological&nbsp; parameters and&nbsp; dominant&nbsp; anthropogenic&nbsp; influences&nbsp; of&nbsp; the studied&nbsp; field&nbsp; sites&nbsp; were&nbsp; shown&nbsp; to&nbsp; affect&nbsp; the presence&nbsp; and&nbsp; abundance&nbsp; of&nbsp; the&nbsp; studied&nbsp; invasive plants.&nbsp; The catchment areas of the Sava, Velika Morava&nbsp; and&nbsp; Južna&nbsp; Morava&nbsp; rivers&nbsp; are&nbsp; excpected to&nbsp; be&nbsp; under&nbsp; a&nbsp; strong&nbsp; pressure&nbsp; of&nbsp; the&nbsp; spread&nbsp; and dominance&nbsp; of&nbsp; IAS&nbsp; unnder&nbsp; the&nbsp; conditions&nbsp; of global&nbsp; climate&nbsp; changes.&nbsp; Riparian&nbsp; areas&nbsp; in&nbsp; the southwestern parts of Serbia (valleys of&nbsp; Lim and Ibar&nbsp; rivers&nbsp; and&nbsp; their&nbsp; tributaries)&nbsp; and&nbsp; riparian zones&nbsp; in&nbsp; the&nbsp; mountain&nbsp; and&nbsp; high- mountain&nbsp; areas are also expected to experience an increase in the number&nbsp; of&nbsp; invasive&nbsp; species&nbsp; and&nbsp; their&nbsp; spread rates.</p>

This thesis is a broadly chronological study of representations of Japan and the Japanese in Australian novels, stories and memoirs from the late nineteenth century to the twenty-first century. Adopting Edward Said???s Orientalist notion of the `Other???, it attempts to elaborate patterns in which Australian authors describe and evaluate the Japanese. As well as examining these patterns of representation, this thesis outlines the course of their development and change over the years, how they relate to the context in which they occur, and how they contribute to the formation of wider Australian views on Japan and the Japanese. The thesis considers the role of certain Australian authors in formulating images and ideas of the Japanese ???Other???. These authors, ranging from fiction writers to journalists, scholars and war memoirists, act as observers, interpreters, translators, and sometimes ???traitors??? in their cross-cultural interactions. The thesis includes work from within and outside ???mainstream??? writings, thus expanding the contexts of Australian literary history. The major ???periods??? of Australian literature discussed in this thesis include: the 1880s to World War II; the Pacific War; the post-war period; and the multicultural period (1980s to 2000). While a comprehensive examination of available literature reveals the powerful and continuing influence of the Pacific War, images of ???the stranger???, ???the enemy??? and later ???the ally??? or ???partner??? are shown to vary according to authors, situations and wider international relations. This thesis also examines gender issues, which are often brought into sharp relief in cross-cultural representations. While typical East-West power-relationships are reflected in gender relations, more complex approaches are also taken by some authors. This thesis argues that, while certain patterns recur, such as versions of the ???Cho-Cho-San??? or ???Madame Butterfly??? story, Japan-related works have given some Australian authors, especially women, opportunities to reveal more ???liberated??? viewpoints than seemed possible in their own cultural context. As the first extensive study of Japan in Australian literary consciousness, this thesis brings to the surface many neglected texts. It shows a pattern of changing interests and interactions between two nations whose economic interactions have usually been explored more deeply than their literary and cultural relations.

Invasive species represent a major concern; they can result in serious ecological and economic losses and are recognised as one of the most serious threats to global species diversity. Plant invasions are of particular concern in New Zealand, which has high proportions of both naturalised and endemic plant species. In this thesis I focussed on the invasive plant Hieracium lepidulum, an exotic weed introduced from Europe to New Zealand prior to 1941. It is invasive in a variety of habitats in the South Island, where it has steadily increased in distribution and abundance over the last 50 years, and is thought to have detrimental impacts on native plant communities. I investigated factors influencing its invasion success and tested for impacts on native plant communities, making extensive use of existing plots into which H. lepidulum was experimentally introduced in 2003. I examined how community richness, turnover, resource availability and propagule pressure of the invader interacted to determine the invasion success of H. lepidulum. Results differed markedly above and below treeline. Above treeline, plots with higher richness and turnover were more invaded; below treeline, plots with higher available light were more invaded. In both habitats, these findings were modified by the influence of propagule pressure; at low propagule pressure, site characteristics were non-significant in explaining invasion success, while at higher propagule pressure these effects became significant. To test for impacts resulting in altered community composition and structure, I looked for changes in community richness, diversity and evenness subsequent to H. lepidulum introduction. As impacts may be more apparent at fine spatial scales, I made measurements at a 5 x 5 cm cell scale in addition to the established 30 x 30 cm plot scale. Plot species richness increased from 2003 to 2009 and a component of this increase was associated with H. lepidulum density. Other relationships between the plant community and H. lepidulum were generally non-significant. Results showed that H. lepidulum has had no negative effects on community richness, evenness or diversity. Despite being able to opportunistically colonise grassland sites with high turnover, and forest sites subject to canopy disturbance, dependant on propagule pressure, it appears H. lepidulum has not impacted community composition or structure.

Many regional and local factors can influence the distribution of native and exotic species in ecological communities. I examined the regional- and local-scale determinants of native and exotic vascular plant species richness and composition in a highly fragmented oak savanna ecosystem on southeastern Vancouver Island. In sharp contrast to most reported results, I found a negative relationship between native and exotic richness at the regional scale, and no relationship at the local scale. Two extrinsic factors, surrounding road density and climate, best explained the regional-scale relationship by each affecting natives and exotics in opposite ways. Road density and climate were also the dominant predictors of native and exotic composition at the regional scale. Patterns in the patch occupancy of individual species confirmed the importance of these factors but I found that low surrounding road densities and cool, wet conditions predicted the presence of many natives and the absence of many exotics. Environmental factors explained variation in richness and composition at the local scale, but these factors were different for natives and exotics. My results suggest that natives and exotics respond to roads and climate in fundamentally different ways. Roads increase both exotic propagule pressure and disturbance, which may facilitate exotic invasion. In contrast, disturbance from roads may increase the likelihood of local extinction for particular natives. Differing climatic preferences within the native and exotic species pools may also partially explain the observed patterns. There was no evidence that native diversity directly affects exotic diversity (or vice versa). Surprisingly, I found that connectivity was not an important predictor of richness or composition despite the high degree of habitat fragmentation in this ecosystem.

Micro (mi)RNAs have recently been found to play an important role in cancer biology. In order to further understand how miRNAs affect prostate tumour progression, we evaluated miRNA expression in two invasive prostate tumour lines, PC3 and DU145. We then focused our evaluation on a novel miRNA, miR-105, whose levels were significantly decreased in both tumour cell lines as compared to normal prostate epithelial cells. As miR-105 levels were reduced in prostate tumour cell lines, we restored its expression following transfection of cells with mimic constructs to over-express miR-105 in both cell lines, in order to determine its effect on various tumourigenic properties. Over-expression caused decreased tumour cell proliferation, anchorage-independent growth and invasion in vitro and inhibited tumour growth in vivo. We further identified CDK6 as a putative target of miR-105, which likely contributed to its inhibition of tumour cell growth. Our results suggest that miR-105 inhibits tumour cell proliferation and may be an interesting target to regulate tumour growth or potentially used as a biomarker to differentiate between less and more aggressive tumours in patients.

Invasive exotic species threaten the biodiversity and function of native ecosystems. Existing models, attempting to predict and control successful invaders, often emphasize isolated stages of in their life history and fail to formalize interactions between exotic species and recipient environments. In order to elucidate key mechanisms in the success of select invaders, I investigated the role of dispersal, establishment, proliferation, and persistence in their threat to natural areas. Focusing on Riding Mountain National Park, Manitoba, Canada, I integrated the native climatic range and biological traits of 251 exotic vascular plants reported inside and outside the park. Based on their climatic range in Europe, 155 among 174 exotic plant species absent from the Park were predicted to establish within its boundaries; among these, 40 clonal perennials were considered the highest threat to the Park’s biodiversity. Focusing on smooth brome (Bromus inermis Leyss.), a Eurasian perennial, threatening the structure and function of native prairies throughout the Great Plains, I extended my research to investigate the role of dispersal, establishment, proliferation, and persistence in characterizing its threat to the endemic diversity of northern fescue prairies, protected within Riding Mountain National Park. Patterns of smooth brome invasions were contingent on the type of propagules dispersed. The shallow dispersal gradient of individual florets combined with the steeper gradient of panicles and spikelets suggested that smooth brome is capable of simultaneously invading along dense fronts as well as by establishing isolated foci. While low correlations between the number of dispersed seeds and their recruitment suggested post-dispersal transport, seedling establishment remained contingent on prairie diversity. Seedling biomass increased with declining plant diversity, however, its impact depended on the availability of soil nitrogen. As a result, disturbed areas, preserving the root function of native plants, resisted smooth brome establishment. Even though low nitrogen contributed to a decline in seedling biomass, physiological integration between ramets facilitated their vegetative proliferation in low resource environments. Despite its rapid establishment and proliferation, smooth brome productivity declined at the center of invading clones. Although field and greenhouse observations failed to implicate soilborne pathogens, reasons for the observed decline remain unresolved. My research demonstrates that while Riding Mountain National Park and other natural areas in western Canada will continue to be impacted by exotic plants, integrating key stages in their life history provides an important conceptual framework in predicting their threat to natural areas and prioritizing management. / October 2008

La formiga argentina (Linepithema humile) es troba entre les espècies més invasores: originària d'Amèrica del Sud, actualment ha envaït nombroses àrees arreu del món. Aquesta tesi doctoral intenta fer una primera anàlisi integrada i multiescalar de la distribució de la formiga argentina mitjançant l'ús de models de nínxol ecològic. D'acord amb els resultats obtinguts, es preveu que la formiga argentina assoleixi una distribució més àmplia que l'actual. Les prediccions obtingudes a partir dels models concorden amb la distribució actualment coneguda i, a més, indiquen àrees a prop de la costa i dels rius principals com a altament favorables per a l'espècie. Aquests resultats corroboren la idea que la formiga argentina no es troba actualment en equilibri amb el medi. D'altra banda, amb el canvi climàtic, s'espera que la distribució de la formiga argentina s'estengui cap a latituds més elevades en ambdós hemisferis, i sofreixi una retracció en els tròpics a escales globals. / Argentine ants (Linepithema humile) rank among the most successful invasive species: native to South America, they have invaded broad areas worldwide. This PhD thesis attempts to take the first step towards an integrated and multi-scalar analysis of the Argentine ant distribution using ecological niche models. According to our results, the Argentine ant is expected to occupy a broader distribution in its worldwide invaded ranges than is currently appreciated. Model predictions are in concordance with the currently known occurrence of the species, and indicate areas near the coast and following the main rivers as highly suitable for the species. These results give additional support to the idea that the Argentine ant is not currently in equilibrium with its environment. According to global climate change scenarios, the Argentine ant is expected to expand to higher northern and southern latitudes, and retract in the tropics at global spatial scales.