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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
221

New Anticancer Secondary Metabolites from an Endophytic Fungus Chaetomium Nigricolor Isolated from Catharanthus Roseus : Structural Elucidation and Molecular Mechanism Underlying Anticancer Effects

Geethanjali, D January 2017 (has links) (PDF)
Cancer has become a major health problem due to its high rate of morbidity and mortality. Severe side effects associated with most of the available anticancer drugs and the development of the drug resistant cells are the major hurdles limiting their application and therapeutic success. Much attention has thus been focused on natural compounds with minimal or no toxicity in humans and having capacity to suppress proliferation and/or induce apoptosis in cancer cells. Therefore, it is imperative to discover and develop new anticancer drugs. Endophytic fungi though underexploited have remained a rich source of structurally novel and biologically active secondary metabolites. That they are a prolific resource for new compounds in drug discovery is evident from a plethora of reported research findings of the recent past. Those of endophytic fungi especially isolated from medicinal plants with known therapeutic value have especially caught the attention of several research groups worldwide for the production of host associated or novel lead molecules. In this backdrop, the focus of my research work has been centered on exploring the endophytic fungal population associated with Catharanthus roseus in search of production of novel anticancer compounds. Twenty endophytic fungi were isolated from different parts of Catharanthus roseus plant. The ethyl acetate (EA) extracts of three week grown liquid cultures of the individual endophytes were assessed in vitro for their cytotoxic activities in HeLa and HepG2 cancer cells using MTT assay. Of all the isolates thus screened, the EA extract from an isolate identified as Chaetomium nigricolor exhibited significant cytotoxicity in the tested cell lines with a better activity profile against HeLa cells. To understand if the liquid culture filtrate or the mycelium harbored the active cytotoxic principle, the C. nigricolor culture filtrate and mycelia was extracted separately using organic solvents with varying polarity namely ethyl acetate, dichloromethane, chloroform and hexane. These extracts were further tested for cytotoxicity induction in HeLa and MCF-7 cells by MTT assay. The ethyl acetate culture filtrate and mycelial extracts showed best cytotoxic activity on HeLa cells compared to other extracts; therefore, the mycelial and culture filtrate ethyl acetate extracts of C. nigricolor were pooled and was used for further work. Hexane culture filtrate extract of C. nigricolor showed best antiproliferative activity against MCF-7 cells. Thus, the compounds with anticancer potential from both ethyl acetate pooled extracts and hexane culture filtrate extract of C. nigricolor were purified using bioassay guided isolation method. This finally resulted in the isolation of two different anticancer compounds, one each from EA pooled extract and Hexane culture filtrate extracts of C. nigricolor named as compound 1 and compound 2, respectively. Based on various analyses including mass spectrometry (MS and MS-MS) and UV-visible, Fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR) spectroscopy, the compounds 1 and 2 were identified as 1, 2 Bis (diethylamino) ethene-1, 2 diol (BDED) and Nonacos-4-enoic acid (NA), respectively An improved understanding of the cellular responses to chemotherapeutic agents in cancer cells and the underlying molecular mechanisms gains particular relevance in the efforts to improve the clinical outcome of chemotherapeutic agents. Arresting the growth of cancer cells in one way or the other and induction of apoptosis in a drug specific manner is the hallmark of almost all the clinically used anticancer drugs. Towards this end, evaluation of the cytotoxic effects of the newly identified compounds on various human cancer cells was carried out. BDED was examined for in vitro cytotoxicity of against a panel of five human cancer cell lines namely HeLa, A-431, A549, COLO 205, and MCF-7. Among the cell lines screened, HeLa cells were most vulnerable to BDED treatment with an IC50 value of 27 μM. This cytotoxicity was later identified as resulting from apoptosis induction by BDED which was scored by the characteristic events of membrane externalization of phosphatidylserine, cytoplasmic shrinkage and chromatin condensation which were observed in a large majority of the BDED-treated cells. Further detailed studies were performed to delineate the cellular mechanisms of BDED-induced apoptosis in HeLa cells. Analysis of cell cycle progression by propidium iodide (PI) staining revealed BDED-induced cell cycle arrest in the G1 phase of cell cycle. The results indicated that BDED induced a significant ROS generation and a significant loss of mitochondrial membrane potential which were abrogated upon pretreatment of the cells with an antioxidant, N-acetyl cysteine (NAC). These observations suggested the probable involvement of the initial events of BDED-induced ROS production in causing cell death via mitochondria-based intrinsic pathway of apoptosis. In addition, the results from the expression profile of pro- and anti- apoptotic proteins by western blot analysis in the BDED-treated HeLa cells further corroborated this hypothesis. These included an abnormally deregulated cellular abundance of BAX 1 and BCL 2 proteins, elevated levels of APAF-1, and activated cleaved species of procaspases 9 and 3. In addition, a pronounced abundance of cleaved PARP protein was observed in these experiments. Thus, the results suggest that BDED induced apoptosis in HeLa cells via ROS mediated mitochondrial dependent pathway. In parallel, the in vitro cytotoxic effects of NA was also studied, the second antiproliferative compound identified from hexane extracts of C. nigricolor using a panel of four human cancer cell lines - A-431, A549, COLO 205, and MCF 7. NA was thus found to be most potent against MCF 7 (breast cancer) cells. PI staining-based viability assays and microscopic observations showed a dose dependent cytotoxicity of NA on MCF 7 cells. Our data reveled an IC 50 of 40 μM for NA The NA-induced apoptosis was confirmed by flow cytometric detection of membrane externalization of phosphatidylserine using Annexin V FITC/PI dual staining. NA was also observed to induce cytotoxicity best at 72 h this could be attributed to the fact that it is a derivative of a Nonocosane-(a naturally prevalent molecule found in several vegetables). Similar to our results from BDED-treated HeLa cells, ROS generation and loss of mitochondrial membrane potential which were abrogated on pretreatment with NAC, were also observed in NA-treated MCF-7cells. Similar to several other fatty acids, NA was also observed to induce cell cycle arrest in the G1 phase of cell cycle. Further, apoptotic signature of an altered expression of anti-apoptotic BCL-2 and pro-apoptotic BAX, APAF-1 and procaspase 9 and 3 and a cleaved PARP were observed in NA-treated MCF 7 cells. In conclusion, the results indicate that BDED and NA have cytotoxic and apoptotic effects on HeLa (cervical cancer) and MCF 7 (breast cancer) cell lines, respectively. This leaves open further avenues to evaluate their potential application as anticancer agents for treatment of human cervical and breast cancers.
222

Wine and innovation - Consumer acceptance of new grape varieties and wine packaging

Nesselhauf, Lucas 29 October 2018 (has links)
No description available.
223

Atividade fungistática de uma quitinase recombinante do feijão de corda [Vigna unguiculata (L.) (Walp.)] contra Lasiodiplodia theobromae Pat. (Griff. e Maubl.), agente causal da resinose do cajueiro (Anacardium occidentale L. / Fungistatic activity of a recombinant chitinase String bean [Vigna unguiculata (L.) (Walp.)] Against Lasiodiplodia theobromae Pat. (Griff . And Maubl.), the causal agent of Resinose cashew (Anacardium occidentale L.)

Lopes Neto, Antônio Viana January 2014 (has links)
LOPES NETO, Antônio Viana. Atividade fungistática de uma quitinase recombinante do feijão de corda [Vigna unguiculata (L.) (Walp.)] contra Lasiodiplodia theobromae Pat. (Griff. e Maubl.), agente causal da resinose do cajueiro (Anacardium occidentale L.). 2014. 57 f. Dissertação (Mestrado em Bioquímica)-Universidade Federal do Ceará, Fortaleza-CE, 2014. / Submitted by Eric Santiago (erichhcl@gmail.com) on 2016-07-08T13:45:57Z No. of bitstreams: 1 2014_dis_avlopesneto.pdf: 1483564 bytes, checksum: 0e776910b7f818898df5c2fc18bff4ec (MD5) / Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-08-02T20:18:18Z (GMT) No. of bitstreams: 1 2014_dis_avlopesneto.pdf: 1483564 bytes, checksum: 0e776910b7f818898df5c2fc18bff4ec (MD5) / Made available in DSpace on 2016-08-02T20:18:18Z (GMT). No. of bitstreams: 1 2014_dis_avlopesneto.pdf: 1483564 bytes, checksum: 0e776910b7f818898df5c2fc18bff4ec (MD5) Previous issue date: 2014 / The aim of this work was to evaluate the biological activity of a recombinant chitinase (rVuChi) from cowpea (Vigna unguiculata) against the phytopathogenic fungus Lasiodiplodia theobromae. The recombinant protein was expressed in Pichia pastoris, collected and purified after 72h of induction, using a chitin affinity chromatography. The chitinase was eluted from the affinity chromatography using 0.1 M acetic acid. Enzymatic assay was performed against the synthetic substrate (colloidal chitin) in order to determine the activity of the purified recombinant protein. The chitinase displayed a specific activity of 5,637.32 U/mg of protein. Biological tests were performed. In these tests three different isolates of L. theobromae, identified as CNPAT CCJ-127, CNPAT CCJ-166 and CNPAT CCJ-184, were used and the experiments were performed on triplicate. The fungal isolates were obtained from the collection of work from the laboratory of plant pathology from the Embrapa Agroindústria Tropical (Fortaleza-CE, Brasil). In all biological assays the fungicide Carbomax 500 SC® (Carbendazim) at a concentration of 2 mL/L and sterile distilled water were used as positive and negative controls, respectively. A total of 50, 100 and 300 µg of recombinant chitinase (rVuChi) was used in all tests. The first test was based on the disk diffusion methodology using filter paper in which the effects of the protein on the mycelium growth, as well as the formation of an inhibition zone on the fungal hyphae were investigated. The second test was based on the diffusion assay in agar. Photographs were used to register the observations. The rVuChi showed moderate to strong fungistatic activities on the mycelial growth of all L. theobromae isolates when used at 100 and 300 µg in the disk diffusion assay. CNPAT CCJ-127 was the most resistant specimen to the rVuChi fungistatic action, as observed by the lower impact of the protein on it is mycelial growth. In the agar diffusion test the amount of 300 µg was the most effective, as observed in the disk diffusion test. In addition, the effect of the protein was most pronounced on the isolates CNPAT CCJ-166 and CNPAT CCJ-184 and less impacting on CNPAT CCJ-127. The recombinant chitinase rVuCHi showed to be an inhibitor of the mycelial growth of three L. theobromae isolates. The fungistatic effects of the protein described here may be due to its ability to degrade chitin, a structural biopolymer that makes part of the cell wall of several phytopathogenic fungi, including L. theobromae. Once this is only a scientific speculation, more studies need to be made to definitely reveal the mechanism of action of rVuChi on L. theobromae. / O objetivo deste trabalho foi avaliar a atividade biológica de uma quitinase recombinante (rVuChi) de feijão-caupi (Vigna unguiculata) contra o fungo fitopatogênico Lasiodiplodia theobromae. A proteína recombinante foi expressa em Pichia pastoris, coletada e purificada após 72h de indução, utilizando cromatografia de afinidade em matriz de quitina. A quitinase foi eluída a partir da cromatografia de afinidade com ácido acético a 0,1 M. Ensaio enzimático foi realizado contra o substrato sintético (quitina coloidal), a fim de determinar a atividade da proteína recombinante purificada. A quitinase apresentou atividade específica de 5.637,32 U/mg de proteína. Testes biológicos foram realizados. Nestes testes três diferentes isolados de L. theobromae, identificados como CNPAT CCJ-127, CNPAT CCJ-166 e CNPAT CCJ-184, foram utilizados e os experimentos foram realizados em triplicata. Os isolados fúngicos foram obtidos da coleção de trabalho do Laboratório de Fitopatologia da Embrapa Agroindústria Tropical (Fortaleza-CE, Brasil). Em todos os ensaios biológicos o fungicida Carbomax 500 SC® (Carbendazim), a uma concentração de 2 mL/L, e água destilada estéril foram utilizados como controles positivos e negativos, respectivamente. Um total de 50, 100 e 300 µg de quitinase recombinante (rVuChi) foi utilizado em todos os testes. O primeiro ensaio foi baseado na metodologia de difusão em disco de papel de filtro em que foram investigados os efeitos da proteína sobre o crescimento do micélio, bem como a formação de halo de inibição sobre o crescimento micelial do fungo. O segundo ensaio foi baseado no ensaio de difusão em ágar. Fotografias foram usadas para registrar as observações. A quitinase rVuChi mostrou efeito fungistático variando de moderado a forte sobre o crescimento micelial de todos os isolados de L. theobromae, particularmente quando usada nas doses de 100 e 300 µg, no ensaio de difusão em disco. CNPAT CCJ-127 foi o isolado mais resistente à ação fungistática de rVuChi, como observado pelo menor impacto da proteína em seu crescimento micelial. No teste de difusão em ágar a quantidade de 300 µg foi a mais efetiva, da mesma forma como observado para o de difusão em disco de papel de filtro. Além disso, o efeito da proteína foi mais pronunciado nos isolados CNPAT CCJ-166 e CNPAT CCJ-184 e menos impactante no isolado CNPAT CCJ-127. A quitinase recombinante rVuCHi mostrou ser um inibidor do crescimento micelial de três diferentes isolados de L. theobromae. Os efeitos fungistáticos da proteína aqui descritos podem ser devido à sua capacidade de degradar quitina, um biopolímero estrutural que faz parte da parede celular de vários fungos fitopatogênicos, incluindo L. theobromae. Entretanto, mais estudos precisam ser conduzidos para revelar os possíveis mecanismos de ação de rVuChi sobre L. theobromae.
224

Efeito de elicitação biótica com o fungo Nomuraea rileyi (Farlow) Samson no metabolismo secundário de plantas aclimatadas de Hypericum polyanthemum Klotzsech ex Reichardt / Effect of biotic stress in secondary metabolism of Hypericum polyanthemum Klotzsech ex Reichardt

Meirelles, Gabriela de Carvalho January 2012 (has links)
Hypericum polyanthemum é uma planta nativa do Sul do Brasil que contém compostos como flavonóides, taninos, derivados de floroglucinol (uliginosina B) e benzopiranos: HP1 (6-isobutiril-5,7-dimetóxi-2,2-dimetilbenzopirano), HP2 (7-hidróxi-6-isobutiril-5- metóxi-2,2-dimetilbenzopirano), e HP3 (5-hidróxi-6-isobutiril-7-metóxi-2,2- dimetillbenzopirano). Esses metabólitos são responsáveis por uma série de atividades biológicas como inibidores da monoaminoxidase (IMAO), antiproliferativa e antitumoral. No presente trabalho modificações na biomassa vegetal e no teor de metabólitos bioativos de plantas de H. polyanthemum cultivadas sob condições controladas e após 18 semanas de aclimatação foram investigadas após elicitação com o fungo Nomuraea rileyi através da adição do microrganismo liofilizado e pulverizado (LP), ou liofilizado, autoclavado e pulverizado (LAP) por curtos e longos períodos de tempo. Plantas cultivadas sob condições controladas tratadas com LAP demonstraram aumento na concentração dos benzopiranos HP1, HP2 e HP3 enquanto LP provocou efeito negativo ou ainda, não alterou a síntese destes compostos. Porém, baixos níveis do floroglucinol uliginosina B foram detectados em todos os tratamentos. Tratamentos com LAP por longos períodos de tempo em plantas cultivadas a campo provocaram aumento de biomassa (2x) e a análise química demonstrou elevação do teor de compostos fenólicos totais nas partes vegetativas das plantas submetidas a todos os tratamentos. Ainda, a análise apontou um diferente grau de acúmulo dos metabólitos, com maiores teores de HP1, HP2, HP3 e uliginosina B sendo encontrados nas partes reprodutivas das plantas tratadas com LAP. A elevação dos metabólitos bioativos em resposta ao elicitor fúngico sugere que estes compostos são induzíveis na resposta de defesa de H. polyanthemum. Os resultados obtidos nesse trabalho são relevantes em virtude da planta não sofrer danos. Assim, o sistema descrito representa uma nova abordagem em pesquisas com plantas visando otimizar condições para a produção de biomassa e metabólitos secundários de interesse medicinal. / Hypericum polyanthemum is a native plant of South Brazil that contains compounds such as flavonoids, tannins, phloroglucinol derivatives (uliginosin B) and benzopyrans: HP1 (6-isobutyryl-5,7-dimethoxy-2,2-dimethylbenzopyran), HP2 (7-hydroxy-6-isobutyryl-5- methoxy-2,2-dimethylbenzopyran), and HP3 (5-hydroxy-6-isobutyryl-7-methoxy-2,2- dimethylbenzopyran). These metabolites are responsible for biological activities such as monoamine oxidase inhibitor, antiproliferative and antitumoral. In this work changes in biomass and bioactive metabolites after elicitation with the fungi Nomuraea riley added as freeze dried culture (DC) or as freeze dried autoclaved cell powder (DACP) for short and long periods of time have been investigated in Hypericum polyanthemum plants grown under controlled conditions and after 18 weeks of field acclimatization. Plants treated with DACP showed increased concentrations of the benzopyrans while the DC affected negatively or did not alter the synthesis of these compounds. Nevertheless, low levels of uliginosin B were detected in all treatments. Long time treatment of field grown acclimatized plants with DACP triggered plant growth doubling the biomass and chemical analyses demonstrated increased total phenolic compounds yields in the vegetative parts of plants submitted to the treatments. Furthermore, the analysis showed different pattern of metabolites accumulation, with higher yields of benzopyrans and uliginosin B accumulated in the reproductive parts of the plants treated with DACP during all experiment. The elevation of bioactive metabolites levels in response to the elicitor suggests that these compounds are inducible in plant defense response of H. polyanthemum. The results obtained are relevant since the plant did not suffer injury. Then, the system described represents a new approach in plant research aimed to optimize the conditions for biomass and accumulation of secondary metabolites.
225

Aspectos clínicos, epidemiológicos e etiológicos de 82 casos de rinossinusite fúngica no Rio Grande do Sul / Clinical, epidemiological and etiological aspects of 82 cases of fungal rhinosinusitis in Rio Grande do Sul

Cardoso, Isabel Cristina Espíndola January 2016 (has links)
Descrição: A rinossinusite fúngica (RSF) é uma infecção oportunística, caracterizada pela inflamação da mucosa nasal e dos seios paranasais. É considerada um problema emergente na clínica médica diária, com prevalência aumentada nas últimas décadas, com etiologia nos mais diversos fungos ubíquos. Objetivos: Este trabalho objetivou analisar todos os casos de RSF pertencentes ao banco de dados do Laboratório de Micologia da Irmandade da Santa Casa de Misericórdia de Porto Alegre, no período de 28 anos (1986-2014), relacionando-os com as características clínicas e epidemiológicas. Materiais e métodos: O estudo foi retrospectivo observacional, resultando em uma série de 82 casos, confirmados histopatologicamente e pelos exames micológicos para identificação de fungos, comparados-os com os achados nas imagens radiológicas. Resultados: Foram identificados 54 casos de RSF por aspergilose, com predominância do agente etiológico Aspergillus fumigatus (14/54), e 27 casos de RSF por fungos diferentes do gênero Aspergillus, com superioridade de isolamento de agentes responsáveis por hialohifomicoses (12/27). Configurado, nestes achados, o ineditismo de três casos em nosso meio, com destaque para o primeiro caso de RSF e infecção humana por Trichoderma asperellum. Conclusões: Estes achados representam a maior casuística brasileira identificada, podendo contribuir para uma melhor compreensão epidemiológica, melhorando os critérios de suspeição médica, refletindo na efetividade dos tratamentos, principalmente, no diagnóstico dos casos de RSF invasiva, com altas taxas de mortalidade. / Description: The fungal rhinosinusitis (FRS) is an opportunistic infection characterized by inflammation of the nasal mucosa and sinuses. It is considered an emerging problem in daily medical practice, with prevalence increased in recent decades, with etiology in diverse ubiquitous fungi. Objectives: This study aimed to analyze all cases of RSF belonging to the Mycology Laboratory of the database of the Brotherhood of the Santa Casa of Misericordia Porto Alegre during the period of 28 years (1986-2014), relating them with the clinical and epidemiological characteristics. Methods: The study was observational retrospective, resulting in a series of 82 cases confirmed by histopathological and mycological examinations for identification of fungi, compared them with the findings on radiographs. Results: We identified 54 cases of aspergillosis by RSF, especially the etiologic agent Aspergillus fumigatus (14/54), and 27 cases of RSF different fungi Aspergillus, with insulation superiority of agents responsible for hyalohyphomycosis (12/27). Configured, these findings, the three cases unprecedented in our country, especially the first case of human infection with RSF and Trichoderma asperellum. Conclusions: These findings represent the largest identified Brazilian series and can contribute to a better epidemiological understanding, improving clinical suspicion criteria, reflecting the effectiveness of treatments, mainly in diagnosing cases of invasive RSF, with high mortality rates.
226

Primeiro relato de isolamento e identificação taxonômica de fungos filamentosos em infecções endodônticas / First report of isolation and taxonomic identification of filament fungus in endodontic infections

Cinthya Cristina Gomes 10 July 2007 (has links)
A proposta deste trabalho foi demonstrar in vivo, por meio de técnicas específicas de isolamento, a presença de fungos filamentosos nos canais radiculares de dentes portadores de necrose pulpar e lesão periapical, relacionar sua presença a pacientes com resposta imunológica comprometida e realizar o estudo taxonômico dos isolados. Foram realizadas culturas de 60 canais radiculares com polpa necrosada e lesão periapical. Os pacientes responderam a um questionário de saúde e assinaram permissão para realização da pesquisa. Após isolamento absoluto e assepsia do campo operatório, as amostras foram coletadas utilizando-se 3 pontas de papel absorvente estéreis inseridas no canal radicular uma a uma, durante 1 minuto. Em campo isolado por duas lamparinas, o material coletado foi inoculado em um tubo de ensaio contendo meio de Saboraud Agar acrescido de Cloranfenicol. Próximo ao campo isolado pelas duas lamparinas, foi colocada uma placa de Petri aberta contendo o mesmo meio de cultura contido no tubo de ensaio, com o intuito de verificar a acuidade do isolamento do campo (controle negativo). Ao mesmo tempo foi efetuado um controle positivo, através de uma placa de Petri que permaneceu aberta durante a coleta, fora do campo isolado. Os tubos e placas de Petri foram mantidos em temperatura ambiente por um período de sete a quatorze dias observando o crescimento micelial. Aqueles que apresentaram crescimento foram semeados em meios específicos para microcultivo CYA Agar, Extrato de Malte Agar, ou Agar Batata. Com o auxílio de microscopia óptica, as colônias foram identificadas em gênero e espécie. Das 60 amostras coletadas, 17 apresentaram cultura positiva para fungos filamentosos, perfazendo um total de 28,3%. O gênero Aspergillus foi isolado, in situ, de 7 amostras (11,6%), sendo que a espécie Aspergillus ustus foi isolada de 3 pacientes (5%). O Aspergillus granulosus, Aspergillus niger e o Aspergillus sydowii foram isoladas de 3 pacientes respectivamente. A espécie Emericella quadriluniata, forma sexuada de Aspergillus, foi isolada de 1 paciente. O gênero Penicillium foi isolado, in situ, de 4 amostras (6,6%), sendo as espécies isoladas: Penicillium implicatum, Penicilium micsynvisk, Penicillium lividum e Penicillium citrionigrum. O gênero Fusarium foi isolado, in situ, de 2 amostras (3,3%), sendo as espécies identificadas como Fusarium moniliforme, Fusarium melanochorum, respectivamente. As espécies Aureobasidium pullulans, Exophiala jeancelmei, Eurotium amstelodame e Cladosporium sphaerospermum foram isoladas in situ de 4 amostras. Todos as amostras nas quais foi isolado fungo filamentoso pertenciam a pacientes com comprometimento da resposta imunológica. Nas placas de Petri empregadas no raio das duas lamparinas, não houve crescimento micelial. Entretanto nas placas controle positivo abertas para verificar a contaminação do meio ambiente houve crescimento de fungos ambientais que não eram compatíveis com os isolados dos canais radiculares, além de não apresentarem culturas puras. Pôde-se concluir que canais radiculares, com necrose pulpar e lesão periapical, podem apresentar cultura positiva para fungos filamentosos e que este resultado, neste estudo, apresentou relação direta com a deficiência da resposta imunológica do hospedeiro. / The purpose of the present study was to evaluate in vivo, with specific techniques that isolates the presence of filament fungus in the root canal of teeth with necrotic pulp and perirradicular disease, see the relationship between the presence of these fungus and patients with immunological deficiency and carry out a taxonomic study of the fungus isolated. It was fulfilled the culture of 60 root canals of teeth with necrotic pulp and perirradicular disease. The patients answered a health questionnaire and signed a term to allow the research. After the absolute isolation and cleaning the operating field the samples were collected using three sterile paper points inserted into the root canal during 1 minute. In an isolated field by two lamps, the collected materials were inoculated in a tube with Saboraud Agar with Cloranfenicol. Nearby the isolated field with lamps it was placed an opened Petri plaque with the same culture material from the tubes with the purpose to verify the perceptiveness of the isolated field (negative control). At the same time it was carried out the positive control group with an opened Petri plaque that was maintained far from the isolated fields. The tubes and the Petri plaque were maintained in atmosphere temperature during seven to fourteen days to observe micelial growth. Those that showed growth were spread on specific environment for microcultivation CYA Agar, Extract of Agar Malt or Agar potato. With the help of an optic microscope the colonies were identified in genre and species. Among the 60 samples collected, 17 showed positive culture for filament fungus, making up a total of 28,3%. The genre Aspergillus was isolated, in situ, of 7 samples (11,6%), and the species Aspergillus ustus was isolated from 3 pacients (5%). The Aspergillus granulosus, Aspergillus niger e o Aspergillus sydowii were isolated from 3 pacients respectivaly. The species Emericella quadriluniata, sexual form of Aspergillus, was isolated from 1 pacient. The genre Penicillium was isolated, in situ, from 4 samples (6,6%), where the species isolated were Penicillium implicatum, Penicilium micsynvisk, Penicillium lividum and Penicillium citrionigrum. The genre Fusarium was isolated, in situ, from 2 samples (3,3%), where the species identified were Fusarium moniliforme, Fusarium melanochorum, respectively. The species Aureobasidium pullulans, Exophiala jeancelmei, Eurotium amstelodame and Cladosporium sphaerospermum were isolated in situ from 4 samples. All the samples where it was isolated the filament fungus belonged to pacients with the imunolgical response compromised. On the Petri plaques employed at the range of the two lamp, it was not seen micelial growth. Thereby, on the positive control plaques, opened to check the contamination of the environment showed the growth of ambiental fungus that were not compatible with the fungus isolated from the root canal, and did not shor pure culture. It was concluded that root canal with necrotic pulp and periapical disease, can show positive culture for filament fungus and these results were directly related to the deficiency of the immunological response of the hostess.
227

Bioprospecção do fungo endofítico Hypoxylon investiens associado à alga marinha Asparagopsis taxiformis: potencial antifúngico, anticolinesterásico e antitumoral / Bioprospecting of the endophytic fungus Hypoxylon investiens associated with seaweed Asparagopsis taxiformis: potential antifungal, antitumor and anticholinesterase

Silva, Airton Damasceno [UNESP] 18 March 2016 (has links)
Submitted by AIRTON DAMASCENO SILVA null (airton.silva@ufv.br) on 2016-04-05T15:38:08Z No. of bitstreams: 1 Dissertação Mestrado versão final.pdf: 4535490 bytes, checksum: 8bb674faf58fdd954d9ebfabaecc42b1 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-04-07T18:23:10Z (GMT) No. of bitstreams: 1 silva_ad_me_araiq.pdf: 4535490 bytes, checksum: 8bb674faf58fdd954d9ebfabaecc42b1 (MD5) / Made available in DSpace on 2016-04-07T18:23:10Z (GMT). No. of bitstreams: 1 silva_ad_me_araiq.pdf: 4535490 bytes, checksum: 8bb674faf58fdd954d9ebfabaecc42b1 (MD5) Previous issue date: 2016-03-18 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O fungo Hypoxylon investiens ocorre em ambientes terrestres e aquáticos, sendo que a maior parte dos estudos já realizados com o gênero Hypoxylon refere-se aos fungos terrestres. Diversas substâncias e atividades biológicas foram determinadas para o gênero e o presente estudo é o primeiro a realizar a bioprospecção de H. investiens associado à alga marinha. Neste trabalho, foram estudados os constituintes químicos produzidos pelo fungo H. investiens e avaliadas algumas atividades biológicas promissoras (antifúngica e citotóxica). O extrato bruto dos metabólitos produzidos em meio líquido de PDB obtido em escala ampliada apresentou forte atividade frente aos fungos fitopatogênicos Cladosporium cladosporioides e Cladosporium sphaerospermum e mostrou-se ativo (75,7% de inibição) frente à linhagem tumoral HCT-116 (carcinoma de cólon). O seu fracionamento por CC em Sephadex LH-20 eluída com metanol resultou em 6 frações (G1 a G6): a fração G4 mostrou forte atividade antifúngica contra linhagens de C. cladosporioides e C. sphaerospermum, além de alto potencial de inibição (97,3%) de células tumorais HCT-116. As frações G5 e G6 também se mostraram ativas frente à linhagem tumoral HCT-116 apresentando, respectivamente, 104,8% e 99,4% de inibição dessa linhagem de células tumorais. A fração G5 apresentou ainda atividade (inibição de 84,5%) contra a linhagem MCF-7 (adenocarcinoma de mama metastático). No entanto, as frações G4 e G6 mostraram-se inativas contra esta linhagem, o que evidenciou a seletividade dessas frações frente às linhagens tumorais testadas. Estes resultados indicaram elevado potencial de produção de metabólitos bioativos por H. investiens. Os procedimentos cromatográficos levaram ao isolamento de 14 substâncias da fração G5, 3 substâncias da fração G6 e de outras 2 substâncias da fração inativa G3. A análise estrutural preliminar por RMN das 17 substâncias isoladas das frações bioativas G5 e G6 indica que devam se tratar de compostos inéditos, derivados do BNT (4,4´,5,5’-tetraidroxi-1,1´-binaftila), sendo que três delas, isoladas da fração G5, tiveram seus esqueletos carbônicos completamente caracterizados, utilizando-se experimentos uni e bidimensionais de RMN e espectrometria de massas de alta resolução. Experimentos adicionais estão em andamento para se determinar a estereoquímica dos centros de quiralidade das substâncias elucidadas, e as demais estruturas estão sob processo de investigação estrutural. Uma das substâncias isoladas da fração não-ativa G3 foi o ácido 3-nitropropanóico, uma toxina mitocondrial produzida por fungos para sua defesa e que foi produzido com alto rendimento (304,5 mg a partir de 605,4 mg da fração G3) por H. investiens. Os resultados obtidos foram promissores, evidenciando a destacada quimiodiversidade de fungos obtidos do ambiente marinho e elevado potencial de bioatividade de seus extratos e frações. Sinalizam ainda para a necessidade de estudos mais aprofundados da química e das propriedades biológicas do fungo H. investiens contribuindo para a exploração sustentável da biodiversidade marinha brasileira. / The fungus Hypoxylon investiens occurs in terrestrial and aquatic environments, and most studies carried out so far on genus Hypoxylon refer to the terrestrial fungal strains. Many compounds and biological activities were determined for the genus and the present study is the first to carry out the bioprospection of H. investiens associated to marine algae. In this work, the chemical constituents produced by a fungal strain of H. investiens were investigated and some promising biological activities were evaluated (antifungal and cytotoxicity). The crude extract of the metabolites produced in PDB liquid medium by H. investiens was obtained in large scale and showed strong activity against the phytopathogenic fungi Cladosporium cladosporioides and C. sphaerospermum. It also showed inhibitory activity (75.7% of inhibition) on colon carcinoma tumor cell line HCT-116. Its fractionation by column chromatography over Sephadex LH-20 eluted with methanol afforded 6 fractions, (G1-G6). Fraction G4 showed strong antifungal activity against C. cladosporioides and C. sphaerospermum strains, in addition to high inibitory potential (97,3%,) towards tumor cells HTC-116. Fractions G5 and G6 were also active against tumor cell line HCT-116, showing 104,8% and 99,4% inhibition, respectively. Additionally, fraction G5 inhibited metastatic breast adenocarcinoma cell line MVF-7 whereas fractions G4 and G6 were inactive, which evidenced selectivity of such fractions towards the tested tumor cells lines. These results evidenced a high potential of production of bioactive metabolites by H. investiens. The chromatographic procedures led to the isolation of 14 compounds from fraction G5, 3 compounds from fraction G6 and 2 compounds from the non-active fraction G3. The preliminary analysis of the 17 isolated compounds from the bioactive fraction G5 and G6 by NMR spectroscopy indicated they are novel compounds structurally related to BNT (4,5,4',5'-tetrahydroxy-1,1'-BiNaphThyl). From those, three compounds were isolated from fraction G5 and had their carbon skeletons fully characterized and consistent with uni and bidimensional 1H and 13C NMR spectral data and high-resolution mass spectrometry. Additional experiments are being developed to determine the stereochemistry of asymmetric centers in the elucidated structures. Additionally, the non-active fraction G3 afforded high yield (304,5 mg from 605,4 mg of G3 fraction) of 3-nitropropanoic acid, a mitochondrial toxin wide spread among fungi and produced for their own defense. The results obtained were promising, pointing out the need for further in-depth investigations on the chemistry and biological properties of the fungus H. investiens. Such promising results evidence the outstanding chemodiversity of marine-derived fungi and highlight the bioactivity potencial of their extracts and fractions. They also point out the need for further studies of H. investiens chemistry and biological properties, which may contribute for the sustainable exploration of Brazilian marine biodiversity.
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Distribuição generalizada da resistência a fungicidas triazóis e evolução do gene cyp51A em populações de Pyricularia oryzae da brusone do trigo no Brasil / Widespread distribution of triazole fungicide resistance and evolution of the cyp51A gene in populations of wheat blast pathogen Pyricularia oryzae in Brazil

Poloni, Nadia Maria [UNESP] 22 February 2016 (has links)
Submitted by Nadia Maria Poloni null (nadiapoloni@gmail.com) on 2016-04-16T00:04:34Z No. of bitstreams: 1 Dissertação - Nadia Poloni - completa.pdf: 1931593 bytes, checksum: e8e92f6dc3b3aa46033959f97f62b795 (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-04-18T12:53:57Z (GMT) No. of bitstreams: 1 polani_nm_me_ilha.pdf: 1931593 bytes, checksum: e8e92f6dc3b3aa46033959f97f62b795 (MD5) / Made available in DSpace on 2016-04-18T12:53:57Z (GMT). No. of bitstreams: 1 polani_nm_me_ilha.pdf: 1931593 bytes, checksum: e8e92f6dc3b3aa46033959f97f62b795 (MD5) Previous issue date: 2016-02-22 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O fungo ascomiceto, Pyricularia oryzae, tem distribuição mundial como patógeno do arroz, mas recentemente emergiu como patógeno causando a brusone do trigo no Brasil. Os grupos de fungicidas estrobirulinas e triazóis tem sido intensivamente utilizados para manejo de doenças do trigo há cerca de três décadas. Há relato de resistência de P. oryzae do trigo a estrobirulinas no Brasil e a ineficácia dos fungicidas triazóis aponta para um cenário semelhante. Os triazóis, inibidores da desmetilação de esteróis (DMI), inibem a biossíntese de ergosterol e possuem como alvo a enzima 14α-demetilase, codificada pelo gene cyp51. Em nosso estudo, determinamos as distribuições de frequência da sensibilidade de 180 isolados de P. oryzae do trigo amostrados de sete estados do Centro-Sul do Brasil, com base na EC50 a tebuconazol e epoxiconazol. Descrevemos, também, a presença de mutações no gene cyp51A e reconstruímos sua filogenia reticulada para esclarecer a relação evolutiva entre haplotipos. Relatamos que todas as populações de P. oryzae amostradas se mostraram insensíveis aos fungicidas testados, comparando-se com as doses recomendadas para o manejo da doença no campo. Com base na sequência do gene cyp51A de P. oryzae do trigo, foram detectados oito haplotipos distintos. Foram encontradas sete mutações não-sinônimas, que podem estar correlacionadas com a resistência à DMI's. / The fungus ascomycete Pyricularia oryzae has worldwide distribution as rice pathogen, but it has recently emerged as pathogen causing wheat blast in Brazil. The strobirulin and azole fungicides have been intensively used for management of wheat diseases in the last three decades. The report of resistance of P. oryzae from wheat to strobirulins in Brazil and the inefficiency of azole fungicides indicates a similar scenario. The triazoles represented sterols demethylation inhibitor fungicides group (DMI), characterized by inhibiting the biosynthesis of ergosterol and their target is the 14α-demethylase enzyme, encoded by the cyp51 gene. We determined the azole sensitivity frequency distributions of 180 isolates of P. oryzae of wheat sampled in seven states of the south-central Brazil, based on the EC50 of tebuconazole and epoxiconazole. We described the presence of mutations in the cyp51A gene and built their reticulate phylogeny to identify the evolutionary relationship among haplotypes. We reported that all P. oryzae populations sampled were insensitive to the azoles when compared to the recommended doses for the management of the disease in the field. Based on the sequence of cyp51A gene from P. oryzae of wheat, eight distinct haplotypes were detected. We found seven non-synonymous mutations that could be correlated with resistance to DMI's.
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Efeito do estado nutricional na resposta imunológica de camundongos BALB/c inoculados com Lacazia loboi

Barbosa, Adriana Sierra Assêncio Almeida [UNESP] 21 September 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:29Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-09-21Bitstream added on 2014-06-13T19:01:45Z : No. of bitstreams: 1 barbosa_asaa_dr_botfm.pdf: 739840 bytes, checksum: 72e238b6e0728303f96f7e2a53f98d98 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / A doença de Jorge Lobo é micose cutânea-subcutânea de evolução crônica causada pelo fungo Lacazia loboi. Esta micose é predominante na região Amazônica e afeta principalmente trabalhadores rurais que vivem em contato constante com a vegetação e o solo, como é o caso dos seringueiros dessa região. Até o momento não existem estudos sobre a participação do estado nutricional na resposta imunológica abordando a doença de Jorge Lobo; assim, este estudo tem por finalidade avaliar os efeitos da desnutrição protéico-calórica na resposta imune de camundongos isogênicos da linhagem BALB/c inoculados com L. loboi, empregando parâmetros imunológicos e histopatológicos. O presente estudo foi desenvolvido com 120 camundongos do sexo masculino, da linhagem BALB/c, com idade aproximada de 12 semanas e cerca de 25g de peso corporal. Foram constituídos quatro grupos: G1: 30 camundongos inoculados com o fungo L. loboi, recebendo restrição dietética de 20% da dieta normal; G2: 30 camundongos não inoculados, recebendo restrição dietética de 20% da dieta normal; G3: 30 camundongos inoculados, recebendo dieta normal; G4: 30 camundongos sadios. Os animais dos grupos G1 e G2 foram submetidos previamente, por 20 dias, antes do início do estudo, a restrição dietética com oferta diária de 80% da quantidade ingerida pelos grupos G3 e G4. Após instalada a desnutrição, os animais foram inoculados no coxim plantar, via intradérmica, com fungo L. loboi e depois de 4 meses (período de aparecimento das lesões macroscópicas no coxim plantar), os animais foram sacrificados e submetidos ao lavado peritoneal e à necrópsia para a retirada dos órgãos: fígado e baço. Os coxins plantares foram removidos para determinação da viabilidade e do número total de fungos, além do histopatológico. As células do lavado peritoneal... / The Jorge Lobo’s disease is a cutaneous and subcutaneous mycosis with chronicle evolution caused by the fungus Lacazia loboi. This mycosis is predominant in the Amazon region and affects mainly rural workers who live in constant contact with the vegetation and the soil, such as the rubber tappers in this region. Up to this date there haven´t been studies about the participation of the nutritional state in the immunological response approaching the Jorge Lobo; thus, this study aims to evaluate the effects of the protein-calorie malnutrition in the immune response of the isogenic mice lineage BALB/c inoculated with L. loboi, using hystopatological and immunological parameters. The present study was developed with 120 male mice lineage BALB/c, with approximately 12 weeks old and circa 25g of body weight. Four groups were made: G1: 30 mice inoculated with L. loboi fungus, receiving diet restriction of 20% of the normal diet; G2: 30 non inoculated mice, receiving diet restriction of 20% of normal diet; G3: 30 mice inoculated receiving normal diet; G4: 30 healthy mice. The animals in the groups G1 and G2 were previously submitted for 20 days before the beginning of the study to a diet restriction with a daily offer of 80% of the quantities ingested by groups G3 e G4. After malnutrition was installed the animals were inoculated in the plantar cushion, via intradermic, with L. loboi fungus and after 4 months (period of the appearance of the macroscopic lesions in the plantar cushion), the animals were sacrificed and submitted to a peritoneal washing and to a necropsy to remove the organs: liver and spleen. The plantar cushions were removed for determining the viability and the total number of fungi, besides the hystopatological. The cells in the peritoneal washing were used for: total cell culture for the dosage of cytokine IFN-γ, macrophage... (Complete abstract click electronic access below)
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Rhizoctonia solani AG-1: estrutura genética, etiologia e evolutibilidade nos agroecossitemas Brachiaria spp. e arroz na Colômbia

Molina, Lina Maria Ramos [UNESP] 31 January 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-01-31Bitstream added on 2014-06-13T20:23:19Z : No. of bitstreams: 1 molina_lmr_dr_jabo.pdf: 480341 bytes, checksum: b838d0062518eb208c7e881bd5eb7588 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / No início dos anos 90, o fungo Rhizoctonia solani emergiu como um patógeno importante associado à morte de pastagens do gênero braquiária na Colômbia. Inicialmente, esse estudo indicou que R. solani AG-1 IA predomina como patógeno associado à queima da folha da braquiária nos Llanos Colombianos. Para o estudo da estrutura genético-populacional do patógeno, um total de 198 isolados de R. solani AG-1 IA foram coletados de campos de B. brizantha cv. Toledo, de Brachiaria híbrido Mulato e do arroz. Os isolados foram genotipados usando dez loci microssatélites. Um sistema reprodutivo misto (reprodução sexuada e clones adaptados) caracterizou as populações de R. solani AG-1 IA que infectam a braquiária. A alta fração clonal e os desvios do equilíbrio de Hardy-Weinberg encontrados foram consistentes com o efeito Wahlund associado à mistura de populações. Padrões históricos de migração entre populações hospedeiro-distintas indicaram a origem provável das populações que infectam braquiária a partir de populações que infectavam arroz. Para determinar o efeito do estresse térmico na evolutibilidade para crescimento micelial, populações de R. solani AG-1 IA infectando braquiária ou arroz e R. oryzae-sativae do arroz, foram submetidas à temperatura ótima e de estresse (25 e 35°C). A herdabilidade para crescimento micelial sob condições de estresse foi considerada alta na população de R. oryzae-sativae do arroz, indicando que os patógenos têm potencial de adaptação à temperatura de 35°C / In the early '90s, the fungus Rhizoctonia solani has emerged as an important pathogen associated with the death of Brachiaria pastures in the Colombian Llanos. Initially, this study indicated that R. solani AG-1 IA was the predominant pathogen associated with the leaf blight in the Colombian Llanos. To study the population genetic structure of the pathogen, a total of 198 isolates of R. solani AG-1 IA were collected from fields of B. brizantha cv. Toledo, Brachiaria Mulato hybrid and from rice. These isolates were genotyped using ten microsatellite loci. A mixed mating system (sexual reproduction and dispersal of adapted clones) characterized the populations of R. solani AG-1 IA infecting Brachiaria. The high clonal fraction and deviations from Hardy-Weinberg equilibrium found in three out of four populations were consistent with Wahlund effect associated with the mixing of populations. Historical patterns of migration between different host-populations indicated that the likely source of the current populations infecting Brachiaria in the Colombian Llanos was from populations that originally infected rice. To determine the effect of heat stress on the evolvability for mycelial growth, two host distinct populations of Rhizoctonia solani AG-1 IA infecting either brachiaria or rice and a rice-infecting population of R. oryzae-sativae, were submitted to optimal and stress temperatures (25°C and 35°C). The heritability values for mycelial growth under heat stress was considered high for rice-infecting population of R. oryzae-sativae, indicating that these pathogen’s population have a high potential to adapt to 35°C temperature

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