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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.
11

Molecular and phenotypic characterization of anamorphic fungi

Madrid Lorca, Hugo 31 May 2011 (has links)
Los hongos anamórficos son un vasto grupo dentro del reino Fungi, caracterizado por reproducirse asexualmente. Aunque la mayoría de ellos son saprófitos, un gran número de especies atacan plantas y animales, incluido el ser humano. Con el fin de contribuir al conocimiento de la diversidad y distribución geográfica de los hongos anamórficos, en la presente tesis se realizó una caracterización fenotípica y molecular de aislamientos ambientales y clínicos de estos hongos. Mediante un estudio de taxonomía polifásica que incluyó morfología, fisiología y análisis de secuencias de ADN, se propusieron los siguientes nuevos taxones: Cladorrhinum flexuosum, C. microsclerotigenum, Fibulochlamys chilensis, Ramophialophora humicola, Sporothrix brunneoviolacea, S. dimorphospora y Leptodiscella brevicatenata, todos ellos aislados desde muestras ambientales, principalmente de suelo. Un estudio filogenético de cepas clínicas del género Sporothrix reveló por primera vez la presencia de S. globosa, una especie recientemente descrita, en México, América Central (Guatemala) y América del Sur (Colombia). / Anamorphic fungi (those reproducing asexually) are a big part of kingdom Fungi. Most of them occur as saprobes in nature, but numerous species are pathogenic to plants and animals including man. With the aim of contributing to the knowledge of the diversity and distribution of anamorphic fungi, we performed a phenotypic and molecular characterization of environmental and clinical isolates of these fungi. Based on a polyphasic taxonomy approach which included morphology, physiology and DNA sequence analyses we described the following new taxa: Cladorrhinum flexuosum, C. microsclerotigenum, Fibulochlamys chilensis, Ramophialophora humicola, Sporothrix brunneoviolacea, S. dimorphospora and Leptodiscella brevicatenata, most of which were isolated from soil. A phylogenetic study of clinical isolates of the genus Sporothrix revealed the presence of the recently described pathogen S. globosa in Mexico, Central (Guatemala) and South America (Colombia) for the first time.
12

Above and Below Ground Fungal Diversity in a Hemlock-dominated Forest Plot in Southern Ontario and the Phylogenetic Placement of a New Ascomycota Subphylum

McLenon-Porter, Teresita Mae 01 August 2008 (has links)
The objective of this thesis was to assess the diversity and community structure of fungi in a forest plot in Ontario using a variety of field sampling and analytical methods. Three broad questions were addressed: 1) How do different measures affect the resulting view of fungal diversity? 2) Do fruiting bodies and soil rDNA sampling detect the same phylogenetic and ecological groups of Agaricomycotina? 3) Will additional rDNA sampling resolve the phylogenetic position of unclassified fungal sequences recovered from environmental sampling? Generally, richness, abundance, and phylogenetic diversity (PD) correspond and identify the same dominant fungal groups in the study site, although in different proportions. Clades with longer branch lengths tend to comprise a larger proportion of diversity when assessed using PD. Three phylogenetic-based comparisons were found to be variable in their ability to detect significant differences. Generally, the Unifrac significance measure (Lozupone et al., 2006) is the most conservative, followed by the P-test (Martin, 2002), and Libshuff library comparison (Singleton et al., 2001) with our dataset. Fruiting body collections and rDNA sampling recover largely different assemblages of fungi at the species level; however, both methods identify the same taxonomic groups at the genus-order level as well as ectomycorrhizal fungi as the dominant functional type of Agaricomycotina. This work also shows that the Soil Clone Group I (SCGI) clade is widespread in soils of diverse origins and represents a novel subphylum of Ascomycota.
13

Above and Below Ground Fungal Diversity in a Hemlock-dominated Forest Plot in Southern Ontario and the Phylogenetic Placement of a New Ascomycota Subphylum

McLenon-Porter, Teresita Mae 01 August 2008 (has links)
The objective of this thesis was to assess the diversity and community structure of fungi in a forest plot in Ontario using a variety of field sampling and analytical methods. Three broad questions were addressed: 1) How do different measures affect the resulting view of fungal diversity? 2) Do fruiting bodies and soil rDNA sampling detect the same phylogenetic and ecological groups of Agaricomycotina? 3) Will additional rDNA sampling resolve the phylogenetic position of unclassified fungal sequences recovered from environmental sampling? Generally, richness, abundance, and phylogenetic diversity (PD) correspond and identify the same dominant fungal groups in the study site, although in different proportions. Clades with longer branch lengths tend to comprise a larger proportion of diversity when assessed using PD. Three phylogenetic-based comparisons were found to be variable in their ability to detect significant differences. Generally, the Unifrac significance measure (Lozupone et al., 2006) is the most conservative, followed by the P-test (Martin, 2002), and Libshuff library comparison (Singleton et al., 2001) with our dataset. Fruiting body collections and rDNA sampling recover largely different assemblages of fungi at the species level; however, both methods identify the same taxonomic groups at the genus-order level as well as ectomycorrhizal fungi as the dominant functional type of Agaricomycotina. This work also shows that the Soil Clone Group I (SCGI) clade is widespread in soils of diverse origins and represents a novel subphylum of Ascomycota.
14

Taxonomia e sistemática de boletaceae (Boletales) para o Brasil

Magnago, Altielys Casale January 2014 (has links)
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas, Programa de Pós-graduação em Biologia de Fungos, Algas e Plantas, Florianópolis, 2014. / Made available in DSpace on 2014-08-06T18:08:28Z (GMT). No. of bitstreams: 1 326354.pdf: 3198757 bytes, checksum: 56434bf89de770ca5875a57e0d968a3d (MD5) Previous issue date: 2014 / O conhecimento sobre os fungos boletoides nas regiões tropicais e subtropicais do hemisfério sul ainda é bastante limitado, havendo escassez de dados acerca da diversidade e distribuição dos mesmos. Com o objetivo de contribuir para o conhecimento de Boletaceae foram estudados materiais coletados em diferentes regiões do Brasil. Quatorze táxons foram identificados em cinco gêneros (Austroboletus, Boletellus, Chalciporus, Fistulinella e Tylopilus), sendo que sete são espécies novas: F. alboaurantiaca (RN), F. conduruensis (BA), F. rhytidocystidiata (ES), T. dimorphicus (AM), T. nigrostipitatus (PB), T. pygmaeus (BA) e T. versiformis (PB). Tylopilus balloui foi registrado pela primeira vez para o Brasil. Fistulinella cinereoalba foi registrada pela primeira vez para o Brasil. Chalciporus trinitensis var. amazonicus foi registrado pela primeira vez para o Espírito Santo e A. festivus é o primeiro registro para Santa Catarina. Boletellus ananas e B. cf. lepidospora foram recoletados nas florestas brasileiras. Para todos os táxons são apresentadas fotografias dos basidiomas, descrições macro e micromorfológicas com ilustrações e microscopia eletrônica de varredura (MEV) dos basidiosporos. Os resultados mostraram uma diversidade pouco conhecida de Boletaceae nas florestas brasileiras e uma indicação de que ainda há mais novidades para a ciência no que diz respeito a essa família. O incremento no conhecimento dos táxons de Boletaceae e a importância ecológica da família devido à associação com plantas hospedeiras dá subsídios importantes para planos de conservação em áreas onde esses táxons ocorrem.<br> / Abstract : Knowledge about boletoid fungi in tropical and subtropical regions of the southern hemisphere is still quite limited and few data regarding their diversity and distribution are available. In order to contribute to the knowledge of the diversity of Boletaceae, specimens from different regions of Brazil were studied. A total of 14 taxa belonging to five genera (Austroboletus, Boletellus, Chalciporus, Fistulinella and Tylopilus) have been identified, from which seven are new species: F. alboaurantiaca (RN), F. conduruensis (BA), F. rhytidocystidiata (ES), T. dimorphicus (AM), T. nigrostipitatus (PB), T. pygmaeus (BA), and T. versiformis (PB). Tylopilus balloui was registered for the first time for Brasil. Fistulinella cinereoalba was registered for the first time for Brazil. Chalciporus trinitensis var. amazonicus was registered for the first time for Espírito Santo, and A. festivus is a new record for Santa Catarina. Boletellus ananas and B. cf. lepidospora were recollected in the Brazilian forests. Photographs of the basidiomes, fully macro and microscopic descriptions with illustrations, and Scanning Electron Microscopy (SEM) of the basidiospores are presented for each species. The results showed that the diversity of Boletaceae in Brazilian forests is still not very well known and indicates that there are more new species for science to be described. The increase in the knowledge about the Boletaceae and the ecological importance of the family due to the association with plants provides data to build conservation plans in areas where these taxa grow.
15

Contribuições taxonômicas e filogenéticas ao estudo de Pterulaceae (Agaricales) coraloides

Dutra, Caio Ambrósio Leal January 2015 (has links)
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas, Programa de Pós-Graduação em Biologia de Fungos, Algas e Plantas, Florianópolis, 2015. / Made available in DSpace on 2015-10-20T03:12:11Z (GMT). No. of bitstreams: 1 334837.pdf: 2471453 bytes, checksum: c8d933918ddca14ab49bb32081552c85 (MD5) Previous issue date: 2015 / Os fungos possuem um papel ecológico fundamental na decomposição e ciclagem de nutrientes. Agaricales inclui um grande grupo de fungos macroscópicos encontrados na natureza e entre seus membros variam desde fungos de vida livre decompositores a simbiontes ectomicorrízicos. Dentre os simbiontes, Pterulaceae chamou atenção recentemente devido a descoberta de espécies cultivadas por formigas. Das 92 espécies de Pterulaceae pelo menos 49 possuem registros de ocorrência na Região Neotropical e 26 no Brasil. A presente dissertação trata do estudo das espécies de Pterulaceae que ocorrem no Brasil sob duas abordagens. O capítulo 1 traz uma abordagem taxonômica, com estudos morfológicos e descrições de espécies, com a apresentação de uma espécie nova, Pterula harrisonii, um novo registro para a Região Neotropical, Deflexula lilaceobrunnea, e um novo registro para o Brasil, Pterula velohorta. O capítulo 2 traz uma abordagem filogenética, com a apresentação de três hipóteses filogenéticas baseadas em dois marcadores moleculares (ITS e LSU), onde é proposta um novo arranjo para a família. Através da análise dos resultados sete clados são propostos para incluir espécies que originalmente pertenciam a Deflexula, Pterula e Pterulicium. Este é o primeiro trabalho de filogenia molecular proposto para resolver as relações filogenéticas de Pterulaceae, abrindo o caminho para futuros estudos sobre a família.<br> / Abstract : Fungi have a key ecological role in decomposition and nutrient cycling. Agaricales includes a large group of macroscopic fungi found in nature and its members ranges from free-living decomposers to ectomycorrhizal symbionts. Among the symbionts, Pterulaceae recently drew attention for the discovery of some species being cultivated by ants. From 92 species of Pterulaceae at least 49 are reported to occur in the Neotropical Region and 26 in Brazil. In this work we studied species of Pterulaceae occurring in Brazil using two approaches. The chapter 1 is a taxonomic approach including morphological studies and species descriptions where a new species to science is presented, Pterula harrisonii; one new record for the Neotropical Region, Deflexula lilaceobrunnea; and one new record for Brazil, Pterula velohorta. In chapter 2 a phylogenetic study is presented showing three phylogenetic hypotheses based on two molecular markers (ITS and LSU), where a new arrangement is proposed for the family. The analysis of these results revealed seven clades harboring species that originally belonged to Deflexula, Pterula and Pterulicium. This is the first study of molecular phylogeny proposed to resolve the phylogenetic relationships of Pterulaceae, paving the way for future studies on the family.
16

Aspectos sobre a ecologia e taxonomia de fungos poliporoides (Basidiomycota) da Mata Atlântica de Santa Catarina, Brasil

Silva, Marco Antonio Borba da January 2013 (has links)
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas, Programa de Pós-Graduação em Biologia de Fungos, Algas e Plantas, Florianópolis, 2013. / Made available in DSpace on 2013-12-06T00:08:44Z (GMT). No. of bitstreams: 1 319753.pdf: 1321186 bytes, checksum: 340974d0e6666e16b102c1f24db09682 (MD5) Previous issue date: 2013 / Políporos é um dos principais grupos de fungos decompositores de madeira, contudo, o conhecimento sobre sua diversidade ainda é escasso. Em Santa Catarina, a sinopse sobre a diversidade dos macromicetos apresenta 247 espécies de fungos, destas, 143 são poliporoides, principalmente da região insular. Para a continuidade e o avanço do conhecimento sobre a diversidade de fungos poliporoides que ocorrem na Mata Atlântica de Santa Catarina, foram estudados aspectos sobre a ecologia de comunidades fúngicas, particularmente de uma área pouco explorada, bem como um complexo taxonômico que ocorre na região. Primeiramente foi avaliada e caracterizada a comunidade de políporos em uma área de Floresta Ombrófila Densa do Parque Nacional da Serra do Itajaí, em termos de riqueza, abundância e funcionalidade. Entre os 152 espécimes coletados 58 espécies foram identificadas. Polyporus dictyopus, Perenniporia martia e Fuscoporia walhbergii foram as espécies dominantes. Com base nas frequências relativas nos diferentes tipos e substratos foram encontrados cinco grupos funcionais, dos quais dois formados por Phylloporia spathulata (em raízes vivas no solo) e Phylloporia chrysita (em lianas vivas) e os outros três constituídos por espécies saprofíticas, sendo cada grupo caracterizado pela presença de uma das espécies dominantes citadas. Finalmente, Phellinus piptadeniae é apresentada como um complexo taxonômico, em processo de especiação, a partir de evidências ecológicas (hospedeiro e distribuição geográfica) e filogenéticas. <br> / Abstract : Polypores is one of the most important groups of wood-decay fungi; however, its diversity knowledge is still scarce. In Santa Catarina state, a synopsis of macrofungi diversity presented 247 species, of which 143 are polypores, mainly from insular region. In order to continue and improve the knowledge about the diversity of polypores, wich are occurring in the Atlantic Forest of Santa Catarina, ecological aspects of fungal communities were studied, in an unexplored area, as well as a complex taxonomy that occurs in the region. Firstly, was described the community of wood-decaying polypores in the Atlantic Rain Forest of Parque Nacional da Serra do Itajai, characterizing the community in terms of richness, abundance and functionality. Among 152 specimens collected 58 species were identified. Polyporus dictyopus, Perenniporia martia and Fuscoporia walhbergii were the dominant species. Based on the relative frequency in the different types of substrates where five functional groups were recognized. Two of them were formed by Phylloporia spathulata (on live roots in the ground) and Phylloporia chrysita (on live trunks); and three other functional groups, consisting of saprophytic species, each of them was characterized by the presence of one of the dominant species. Finally, Phellinus piptadeniae is presented as a taxonomic complex, in a speciation process, evidenced by the existence of two phylogenetic and ecological (host and geographic distribution) lineages.
17

Additions to the Mycota of the Seychelles

Watling, R., Seaward, Mark R.D. January 2014 (has links)
No / Eleven species of fungi and one slime-mould are added to the previous list of fungi from Indian Ocean islands made by the authors in 2004. Two other species in the area are confirmed. Our knowledge of fungal distributions in these remote islands is extended and comments are made on some immature collections. This small collection does, however, indicate a palaeotropical element to the mycota with bias towards species found in Southeast Asia, although some have a worldwide distribution.
18

Antitumor effects of polysaccharides extracted from mushroom sclerotia: an in vitro and in vivo study.

January 2005 (has links)
Lai Kin Ming Connie. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 121-141). / Abstracts in English and Chinese. / Chapter Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Introduction on growth cycle of mushroom --- p.1 / Chapter 1.2 --- Literature review of mushroom biological activities --- p.3 / Chapter 1.2.1 --- Various bioactivities of mushroom --- p.3 / Chapter 1.2.2 --- Components responsible for various bioactivities of mushrooms --- p.3 / Chapter 1.3 --- Mushroom polysaccharides and polysaccharide-protein complexes --- p.5 / Chapter 1.3.1 --- Polysaccharides important for antitumor effects --- p.5 / Chapter 1.3.2 --- Polysaccharide-protein complexes important for antitumor effects --- p.7 / Chapter 1.4 --- Structure-function relationship of antitumor activities of polysaccharides --- p.8 / Chapter 1.4.1 --- Effect of molecular mass --- p.8 / Chapter 1.4.2 --- Effect of linkages --- p.9 / Chapter 1.4.3 --- Effect of degree of branching --- p.9 / Chapter 1.4.4 --- Effect of conformation --- p.10 / Chapter 1.5 --- Immunomodulatory effects of mushroom polysaccharides and polysaccharide-protein complexes --- p.11 / Chapter 1.5.1 --- Immunomodulatory effects of polysaccharides --- p.11 / Chapter 1.5.1.1 --- Bioactive polysaccharides in Lentinus edodes --- p.11 / Chapter 1.5.1.2 --- Bioactive polysaccharides in Ganoderma lucidum --- p.12 / Chapter 1.5.2 --- Immunomodulatory effects of polysaccharide-protein complexes --- p.12 / Chapter 1.5.2.1 --- Bioactive polysaccharide-protein complexes in Trametes versicolor --- p.13 / Chapter 1.5.3 --- Immunotherapeutic effects of mushroom polysaccharides --- p.14 / Chapter 1.6 --- Cell cycle and apoptosis --- p.14 / Chapter 1.6.1 --- Introduction of cell cycle --- p.14 / Chapter 1.6.2 --- Cell cycle regulation --- p.15 / Chapter 1.6.3 --- Antitumor effects through apoptotic gene regulation --- p.17 / Chapter 1.7 --- Mushroom sclerotium with antitumor activity --- p.20 / Chapter 1.7.1 --- Literature review on Pleurotus tuber-regium --- p.20 / Chapter 1.7.2 --- Literature review on Poria cocos --- p.22 / Chapter 1.7.3 --- Literature review on Polyporus rhinocerus --- p.23 / Chapter 1.8 --- Objectives --- p.23 / Chapter Chapter 2. --- Materials and Methods --- p.25 / Chapter 2.1 --- Materials --- p.25 / Chapter 2.1.1 --- Mushroom sclerotia --- p.25 / Chapter 2.1.2 --- Animal Model --- p.25 / Chapter 2.1.3 --- Cell lines --- p.27 / Chapter 2.2 --- Methods --- p.28 / Chapter 2.2.1 --- Extraction Scheme for mushroom sclerotia --- p.28 / Chapter 2.2.1.1 --- Hot water extraction only --- p.28 / Chapter 2.2.1.2 --- Sequential extraction scheme --- p.28 / Chapter 2.2.2 --- Measurement of monosaccharide profile --- p.31 / Chapter 2.2.2.1 --- Acid Depolymerisation --- p.31 / Chapter 2.2.2.2 --- Neutral Sugar Derivatization --- p.31 / Chapter 2.2.2.3 --- Gas Chromatography (GC) --- p.32 / Chapter 2.2.3 --- High Pressure Liquid Chromatography (HPLC) --- p.33 / Chapter 2.2.3.1 --- Size exclusion chromatography --- p.33 / Chapter 2.2.3.2 --- Anion exchange chromatography --- p.34 / Chapter 2.2.4 --- Linkage analysis by methylation --- p.34 / Chapter 2.2.4.1 --- Preparation of partially methylated polysaccharides --- p.34 / Chapter 2.2.4.2 --- Preparation of partially methylated alditol acetates (PMAAs) --- p.37 / Chapter 2.2.4.3 --- Gas chromatography-Mass spectrometry (GC-MS) analysis --- p.37 / Chapter 2.2.5 --- Determination of total sugar by phenol-sulphuric acid Method --- p.38 / Chapter 2.2.6 --- Determination of acidic sugars by measurement of uronic acid content --- p.39 / Chapter 2.2.7 --- Determination of protein content by Lowry-Folin method --- p.40 / Chapter 2.2.8 --- Chemical modification by carboxymethylation --- p.41 / Chapter 2.2.9 --- In vitro antitumor assay --- p.41 / Chapter 2.2.9.1 --- Trypan blue exclusion assay --- p.42 / Chapter 2.2.9.2 --- MTT Assay --- p.42 / Chapter 2.2.10 --- Cell cycle analysis by Flow Cytometry --- p.43 / Chapter 2.2.11 --- In vivo antitumor and immunomodulatory assay --- p.44 / Chapter 2.2.11.1 --- Measurement on tumor growth --- p.44 / Chapter 2.2.11.2 --- Blood sampling for immunostimulatory effects --- p.45 / Chapter 2.2.12 --- Mouse Cytokine Array --- p.45 / Chapter 2.2.13 --- Quantification of Mouse IL-13 by ELISA --- p.46 / Chapter 2.2.14 --- Enumeration of peritoneal cells --- p.47 / Chapter 2.2.15 --- Enumeration of splenocytes --- p.49 / Chapter 2.2.16 --- Statistical methods --- p.50 / Chapter Chapter 3. --- Results and Discussion --- p.51 / Chapter 3.1 --- Yield of crude mushroom sclerotial extracts --- p.51 / Chapter 3.2 --- Chemical composition of crude mushroom sclerotial extracts --- p.57 / Chapter 3.2.1 --- Total carbohydrate content --- p.57 / Chapter 3.2.2 --- Uronic acid content --- p.58 / Chapter 3.2.3 --- Soluble protein content --- p.58 / Chapter 3.3 --- Monosaccharide profiles of mushroom sclerotial extracts by GC --- p.60 / Chapter 3.4 --- Chromatographic analyses of mushroom sclerotial extracts --- p.65 / Chapter 3.4.1 --- Molecular weight profile by size exclusion chromatography (SEC) --- p.65 / Chapter 3.4.2 --- Charge distribution by ion exchange chromatography (IEC) --- p.73 / Chapter 3.5 --- Antitumor effects of mushroom sclerotial extracts from hot water extraction alone --- p.73 / Chapter 3.5.1 --- In vitro antiproliferative study by HL-60 --- p.73 / Chapter 3.5.2 --- In vitro antiproliferative study by MCF-7 --- p.74 / Chapter 3.5.3 --- In vivo antitumor study by BALB/c mice --- p.75 / Chapter 3.6 --- Antitumor effects of extracts from sequential extraction scheme --- p.76 / Chapter 3.6.1 --- In vitro antiproliferative study by HL-60 --- p.76 / Chapter 3.6.2 --- In vitro antiproliferative study by MCF-7 --- p.78 / Chapter 3.6.3 --- In vivo antitumor study by BALB/c mice --- p.80 / Chapter 3.7 --- Comparison of in vitro and in vivo activities of mushroom sclerotial extracts --- p.82 / Chapter 3.8 --- Dose-response relationship of hot water extract from PR on cancer cell lines --- p.85 / Chapter 3.8.1 --- In vitro dose-response antiproliferation of PR-W and PR-HWE on HL-60 --- p.85 / Chapter 3.8.2 --- In vitro dose-response antiproliferation of PR-W on K562 and S180 --- p.88 / Chapter 3.8.3 --- In vivo dose-response relationship of PR-W on S180 --- p.91 / Chapter 3.9 --- Flow cytometric analysis of PR-W on cancer cell lines --- p.92 / Chapter 3.9.1 --- Antiproliferative effect of PR-W on HL-60 --- p.92 / Chapter 3.9.2 --- Antiproliferative effect of PR-W on K562 --- p.95 / Chapter 3.9.3 --- Proposed mechanisms of cell cycle arrest by PR-W --- p.98 / Chapter 3.10 --- Host-mediated antitumor mechanism of PR-W --- p.100 / Chapter 3.10.1 --- Mouse cytokine array --- p.100 / Chapter 3.10.2 --- Quantification of IL-13 by ELISA --- p.105 / Chapter 3.10.3 --- Immunostimulatory effects of PR-W on mice --- p.109 / Chapter 3.11 --- Correlation between antitumor activity and structure of mushroom sclerotial extract from hot water extraction alone --- p.114 / Chapter Chapter 4. --- Conclusions and Future works --- p.118 / List of References --- p.121 / Related Publications --- p.142
19

In vivo and in vitro study of immunomodulatory activities of mushroom sclerotial polysaccharides. / CUHK electronic theses & dissertations collection

January 2008 (has links)
Athymic nude mice were employed as the in vivo model to study the detailed mechanism of how the three sclerotial polysaccharides act to inhibit the growth of human xenografted tumors in vivo. Using immunohistochemical staining, it was found that the presence of F4/80 + macrophages was related to the reduction of tumor size of the HL-60 xenograft. mRNA extracted from the spleens were reverse-transcribed to cDNA and detected by real-time PCR so that a variety of genes related to the toll-like receptors being up-regulated or down-regulated due to the injection of mushroom sclerotial polysaccharides were determined. Combining the results from dectin-1 regulation, it was concluded that both hot water-soluble sclerotial polysaccharides, PTRW and PRW, having a structure of polysaccharide-protein complexes were responsible for activating and thus binding to CR3 or toll-like receptors while PRSon with structure of pure beta-glucan was responsible for activating the expression of dectin-1 receptor, which led to the subsequent activation of host immune system in immunopotentiation and antitumor activities. / In the future, further investigation of the detailed structure of mushroom sclerotial polysaccharides is required to explain the immunomodulatory mechanism so that the effective dosage for immunomodulation as well as antitumor effects can be determined. Furthermore, phage display can be applied to find out any novel glucan receptors specific to the mushroom sclerotial polysaccharides. / In vitro antitumor study indicated that PTRW had a significant (p&lt;0.05) inhibitory effect (>40%) on the human monocytic leukemic cells (THP-1) in addition to HL-60 and K562 cells. In vitro immunomodulatory study showed that both PRW and PRSon had significant proliferative effects (p&lt;0.05) on human normal spleen monocyte/macrophage cell, MD. Moreover, PRSon was shown to have a significant increase (p&lt;0.05) in the growth of human natural killer cells, NK-92M1; however, PTRW showed a significant inhibition (p&lt;0.05) on this cell line. / Mushroom sclerotia have a rich source of polysaccharides when compared with fruit bodies. It was previously reported that the polysaccharides from novel mushroom sclerotia, namely, Pleurotus tuber-regium and Polyporus rhinocerus, had potent in vitro and in vivo antitumor effects. In this project, hot water-soluble sclerotial polysaccharides of Pleurotus tuber-regium (PTRW), hot water-soluble and sonication-assisted cold alkali-soluble sclerotial polysaccharides of Polyporus rhinocerus (PRW and PRSon, respectively) were chosen for investigation of their in vivo and in vitro immunomodulatory effects. / Polysaccharides have long been proposed to exert their antitumor and thus immunomodulating functions through glucan receptors and among the four being discovered, Dectin-1 has drawn most attention recently. In the in vivo study, PRSon showed an increase in the expression of Dectin-1 on mice spleen MNCs while PTRW showed an increase in the expression of the previously widely-reported complement receptor (CR3). There was also an increase of Dectin-1 expression on PEC in the mice injected with PRSon. In the in vitro study, the three mushroom sclerotial polysaccharides were incubated with NK-92M1, MD and THP-1 cells. There was a significant increase (p&lt;0.05) of Dectin-1 expression on NK-92MI cells incubated with PTRW. On the other hand, PTRW caused a significant decrease ( p&lt;0.05) of Dectin-1 expression while PRSon showed a significant increase (p&lt;0.05) on THP-1 cells. The cytokine profile of extra-cellular media indicated that the inhibition of THP-1 cells by PTRW should be related to the innate immunity. In the in vitro study, human primary immune cells, CD56+ NK cells were used to incubate with sclerotial polysaccharides and there was a significant stimulation (p&lt;0.05) of their growth when compared with the control. / The in vivo immunomodulatory study was carried out by injecting the abovementioned sclerotial polysaccharides intraperitoneal to 7-8 weeks old healthy male BALB/c mice. The spleens excised from groups injected with PTRW and PRW were found to have significant increase of weight ( p&lt;0.001). Flow cytometric analysis revealed that the NK cell population in spleen mononuclear cells (MNCs) of mice injected with PRW and PRSon was increased when compared with the control. In addition, ail three sclerotial polysaccharides showed a large increase of T helper cell population as well as CD4+/CD8+ ratio in spleen MNCs. On the other hand, the macrophage population in peritoneal exudates cells (PEC) was found to be increased in the groups of mice injected with PTRW and PRW. / Lai, Kin Ming Connie. / Adviser: Cheung Chi Keung. / Source: Dissertation Abstracts International, Volume: 70-06, Section: B, page: 3412. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 120-137). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
20

O G?nero Cyathus haller: pers. (Agaricales, Basidiomycota) em ?reas de caatinga do Nordeste brasileiro

Cruz, Rhudson Henrique Santos Ferreira da 18 March 2013 (has links)
Made available in DSpace on 2014-12-17T15:49:12Z (GMT). No. of bitstreams: 1 RhudsonHSFC_DISSERT.pdf: 5005039 bytes, checksum: 70dbb1bcaa5bc237d15fad417a79c1ee (MD5) Previous issue date: 2013-03-18 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Fungi of the family Nidulariaceae or bird s nest fungi present a vase-shaped basidiomata with the wall surface smooth or striated lengthwise and internal structures resembling small bird eggs in a nest, the peridioles. Among the five genera that comprise the group, the more representative is Cyathus Haller: Pers. The Brazilian Northeast region shows major importance for the world s diversity by containing a Brazilian unique and exclusively phytoecological domain, the Caatinga, which lacks particular attention regarding macrofungi. Although the gradual growth of knowledge in recent years, studies are still insipient in the Caatinga domain. Between their various vegetal formations are the Brejos de Altitude , described as islands with moist perennial vegetation, low soil fertility and annual precipitation of 900 1.300 mm. This study aimed to evaluate the taxonomic richness of Nidulariaceae fungi in Caatinga s areas of Northeastern Brazil, describing and identifying species, as well as expanding the collection of Herbarium UFRN Fungos. For description of Nidulariaceae fungi was followed the proposed by specialized literature in the group. We have found and described 10 species of the genus Cyathus, namely: C. earlei Lloyd, C. gayanus Tul. & C. Tul., C. gracilis H.J. Brodie, C. intermedius (Mont.) Tul. & C. Tul., C. limbatus Tul. & C. Tul., C. montagnei Tul. & C. Tul., C. pallidus Berk. & M.A. Curtis, C. poeppigii Tul. & C. Tul., C. striatus (Huds.) Willd. and C. tr?plex Lloyd. Beyond these have been described four new species to science: Cyathus calvescens R. Cruz & Baseia sp. nov., C. hortum R. Cruz & Baseia sp. nov., C. magnomuralis R. Cruz & Baseia sp. nov. and C. parvocinereus R. Cruz & Baseia sp. nov. Two samples were identified only to genus level. No member of Mycocalia J.T. Palmer, Nidula V.S. White, Nidularia Fr. and Crucibulum Tul. & C. Tul. has been found, however the results were extremely valuable for being an unprecedented work in Caatinga, and importante tool for implementation of conservation projects and sustainable utilization of this domain / Os Fungos da fam?lia Nidulariaceae, ou fungos ninho-de-p?ssaro , apresentam basidiomas em forma de vaso, com a superf?cie da parede lisa ou estriada longitudinalmente e estruturas internas que se assemelham a pequenos ovos de p?ssaros dentro de um ninho, os perid?olos. Dentre os cinco g?neros que comp?em o grupo, o mais representativo ? Cyathus Haller: Pers. O Nordeste Brasileiro apresenta grande import?ncia para a diversidade mundial por conter um dom?nio fitoecol?gico ?nico e exclusivamente brasileiro, a Caatinga, o qual carece de aten??o especial quanto aos macrofungos. Apesar do crescimento gradual de conhecimento nos ?ltimos anos, os estudos ainda s?o incipientes no dom?nio Caatinga. Entre as suas diversas forma??es vegetais existem os Brejos de Altitude, caracterizados como ilhas ?midas de vegeta??o perenif?lia, solo de baixa fertilidade e precipita??o anual entre 900 1.300 mm. Este trabalho visou levantar a riqueza taxon?mica dos fungos nidulari?ceos em ?reas de Caatinga do Nordeste Brasileiro, descrevendo e identificando esp?cies, bem como ampliando a cole??o do herb?rio UFRN Fungos. Para descri??o de fungos nidulari?ceos seguiu-se a proposta em literaturas especializadas do grupo. Foram encontradas e identificadas 10 esp?cies do g?nero Cyathus, a saber: C. earlei Lloyd, C. gayanus Tul. & C. Tul., C. gracilis H.J. Brodie, C. intermedius (Mont.) Tul. & C. Tul., C. limbatus Tul. & C. Tul., C. montagnei Tul. & C. Tul., C. pallidus Berk. & M.A. Curtis, C. poeppigii Tul. & C. Tul., C. striatus (Huds.) Willd. e C. tr?plex Lloyd. Al?m dessas foram descritas 4 novas esp?cies para a ci?ncia: Cyathus calvescens R. Cruz & Baseia sp. nov., C. hortum R. Cruz & Baseia sp. nov., C. magnomuralis R. Cruz & Baseia sp. nov. e C. parvocinereus R. Cruz & Baseia sp. nov. Duas amostras foram identificadas apenas a n?vel de g?nero. Nenhum membro de Mycocalia J.T. Palmer, Nidula V.S. White, Nidularia Fr. e Crucibulum Tul. & C. Tul. foi encontrado, contudo os resultados foram de grande valia por ser um trabalho in?dito na Caatinga e importante subs?dio para aplica??o de projetos de conserva??o e utiliza??o sustent?vel do dom?nio

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