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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.
31

Avaliação do efeito de derivados de parede celular de levedura de cana-de-açúcar (Saccharomyces cerevisiae) sobre a resposta imune de cães adultos /

Zaine, Leandro. January 2010 (has links)
Orientador: Aulus Cavalieri Carciofi / Banca: Helio Jose Montassier / Banca: Iracilda Zeppone Carlos / Resumo: Vários derivados da parede celular da levedura Saccharomyces cerevisiae conhecidamente agem sobre a imunidade, no entanto a ação, especialmente da fração beta-glucano, foi pouco demonstrada em cães. Para o estudo dos possíveis efeitos sobre a imunidade na espécie canina foram empregadas quatro dietas isonutrientes, contendo uma fonte de parede celular de levedura (PCL), duas fontes de beta-glucano (BG1 e BG2) e uma dieta controle (CT). Foram utilizados 24 cães da raça beagle, adultos, divididos em quatro grupos de seis animais. As dietas foram fornecidas por um período total de 126 dias e as avaliações incluíram hemograma e avaliações bioquímicas, dosagem de anticorpos anti-Leptospira, imunofenotipagem de linfócitos sanguíneos, avaliação da concentração de IgA em fezes, teste de hipersensibilidade cutânea tardia e dosagens de citocinas em sobrenadante de cultura celular. Os animais foram submetidos a desafio antigênico com vacina contra leptospirose no dia 42. Os dados foram avaliados pelo procedimento GLM do SAS, sendo as médias comparadas pelo teste de Tukey (p≤0,1). Nos exames bioquímicos houve discreta variação entre os tratamentos e ao longo dos dias. No hemograma notou-se aumento dos linfócitos para BG2. A dosagem de anticorpos anti-Leptospira, mostrou baixos títulos, não havendo boa resposta à vacinação. A imunofenotipagem revelou um aumento dos linfócitos T totais, T helper, T citotóxicos e linfócitos B no grupo BG2 e de linfócitos T citotóxicos e linfócitos B para o grupo PCL. Apesar da variação da concentração de IgA fecal ao longo dos dias, os tratamentos não influenciaram tais parâmetros. O teste de hipersensibilidade cutânea tardia mostrou um aumento na resposta à inoculação da vacina, para os grupos PCL e BG2. Na dosagem de citocinas em sobrenadante de cultura celular, apenas foi observada diferença na quantificação de TNF-α, ...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Some products from the cell wall of the yeast Saccharomyces cerevisiae are known to act on the immunity, however this action, especially of the beta-glucan fraction, has never been demonstrated in dogs. To study these effects on the immunity of dogs four isonutrient diets were made, containing one source of yeast cell wall (YCW), two sources of beta-glucan (BG1 and BG2) and a control diet (CT). 24 adult beagle dogs were used, divided in four groups of six animals. Diets were given for a 126 days period. Evaluations included complete blood count and biochemistry profile, quantification of antibodies against Leptospira, immunophenotyping of blood lymphocytes, IgA concentration in feces, delayed-type hypersensitivity test and quantification of cytokines in cell culture supernatant. Animals were exposed to antigen challenge, by the vaccine against leptospirosis on day 42. Data were analyzed by the GLM procedure of the SAS software and the means were compared by the Tukey test (p<0,01). Biochemistry profile showed slight differences among the groups. A increase in lymphocyte count was observed for BG2 treatment. Quantification of antibodies against Leptospira showed low titles, with poor response to vaccination. Immunophenotyping revealed an increase during the time in total T cells, helper and cytotoxic T cells, and B lymphocytes for BG2 and of cytotoxic T cells and B lymphocytes for YCW group. Despite the variation in fecal IgA concentration during the time, treatments did not influence these parameters. Delayed-type hypersensitivity test showed an increased response to the vaccine inoculation, for YCW and BG2 groups. In the quantification of cytokines in cell culture supernatant the only difference observed was in TNF-α concentration, being BG2 higher than CT. We concluded that both yeast cell wall and beta-glucan fraction act on dogs' immunity / Mestre
32

Potencial prebiótico de diferentes concentrados de fibra alimentar na dieta de juvenis de jundiá (Rhamdia quelen) / Potential prebiotic of different dietary fiber concentrates in feed of juveniles jundiá (Rhamdia quelen)

Goulart, Fernanda Rodrigues 06 February 2015 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The traditional use of antibiotics in aquaculture as growth promoters has been limited due to the negative effects caused by these drugs. As an alternative to the use of these drugs has been sought manipulation of the microbiota of the gastrointestinal tract of aquatic animals through the use of oligosaccharides and dietary fibers with prebiotic potential. Thus, this study aimed to apply different methodologies to obtain Dietary Fiber Concentrates (DFC) = mucilage (MG); pectin (PN) and β-glucan + manan (βG + M) and evaluate the prebiotic potential of these supplements in the diet of juvenile jundiá (Rhamdia quelen). The determination of the nutritional composition of the ingredients revealed that the predominant component in all DFCs were dietary fiber and insoluble fiber. The DFC that had higher extraction yield was βG + M (19.81 ± 8.54%), followed by pectin (14.54% ± 2.72), and mucilage (7.18 ± 1.54%). The composition of mucilage and pectin had a greater diversity of monosaccharides, since the βG+M consisted primarily of mannose (74.5%) and glucose (24.3%). The supplementation of DFC in jundiás diet was assessed for eight weeks through study of growth, body nutrient deposition, digestive enzymes, biochemical and metabolic parameters, responses to stress and immune and intestinal morphology. The jundiás supplemented with DFCs achieved higher growth than the control group and similar to animals supplemented with 5 g kg-1 commercial prebiotic (CP 5). Most somatic parameters and whole fish proximate composition were influenced by supplementation of DFCs. The supplementation of pectin promoted lower activity of digestive enzymes in relation the control group. The animals supplemented with DFC obtained positive changes in biochemical parameters. Furthermore, jundiás showed no response to application of the stressor, maintaining basal cortisol levels. The fish supplemented with DFCs had higher hepatic glycogen stores in relation the control group. Moreover, supplementation with DFCs increased the height of intestinal villi of jundiá. However, these values were lower for the animals of the group PC 5. For thickness of the epithelium this variable was higher in the control group compared to animals supplemented with β-glucan+Manana. / O uso tradicional de antibióticos na aquicultura como promotores de crescimento tem sido limitado em função dos efeitos negativos promovidos por estes medicamentos. Como alternativa ao uso destas drogas, tem se buscado a manipulação da microbiota do trato gastrointestinal dos animais aquáticos através da utilização de oligossacarídeos e de fibras alimentares com potencial prebiótico. Neste sentido, este estudo teve como objetivo aplicar metodologias para obtenção de diferentes Concentrados de Fibras Alimentares (CFAs) = Mucilagem (MG); Pectina (PN) e β-Glicana+Mananas (βG+M) e avaliar o potencial prebiótico destes suplementos na dieta de juvenis de jundiá (Rhamdia quelen). A determinação da composição nutricional dos ingredientes revelou que os componentes predominantes em todos os CFAs obtidos foram fibra alimentar total e fibra insolúvel. O CFA que apresentou maior rentabilidade de extração foi a βG+M (19,81%±8,54), seguida da Pectina (14,54%±2,72) e Mucilagem (7,18%±1,54). A composição da Mucilagem e Pectina obtiveram maior diversidade de monossacarídeos, já a βG+M consistiu basicamente de manose (74,5%) e glicose (24,3%). A suplementação dos CFAs na dieta de jundiás foi avaliada durante oito semanas, através de estudo de crescimento, deposição corporal de nutrientes, enzimas digestivas, parâmetros bioquímicos e metabólicos, resposta ao estresse e imunológica e morfometria intestinal. Os jundiás suplementados com os CFAs obtiveram crescimento superior em relação ao grupo controle e similar aos animais suplementados com 5 g kg-1 de prebiótico comercial (PC 5). A maioria dos parâmetros somáticos e de composição centesimal de peixe inteiro foram influenciados pela suplementação dos CFAs. A suplementação de Pectina promoveu menor atividade das enzimas digestivas em relação ao grupo controle. Os animais suplementados com os CFAs obtiveram alterações positivas nos parâmetros bioquímicos avaliados. Além disso, os jundiás não mostraram resposta à aplicação do agente estressor, mantendo os níveis de cortisol basal. Os peixes suplementados com os CFAs obtiveram maiores estoques de glicogênio hepático em relação ao grupo controle. Além do mais, a suplementação com os CFAs promoveu aumento na altura de vilos intestinais dos jundiás. Porém, estes valores foram menores em relação aos animais do grupo PC 5. Para espessura do epitélio (EE) esta variável foi maior no grupo Controle comparado aos animais suplementados com β- glicana + Manana.
33

Avaliação do efeito de derivados de parede celular de levedura de cana-de-açúcar (Saccharomyces cerevisiae) sobre a resposta imune de cães adultos

Zaine, Leandro [UNESP] 23 February 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-23Bitstream added on 2014-06-13T20:11:36Z : No. of bitstreams: 1 zaine_l_me_jabo.pdf: 606188 bytes, checksum: da0b30ee696bae955544945c1be515d9 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Biorigin Sa / Vários derivados da parede celular da levedura Saccharomyces cerevisiae conhecidamente agem sobre a imunidade, no entanto a ação, especialmente da fração beta-glucano, foi pouco demonstrada em cães. Para o estudo dos possíveis efeitos sobre a imunidade na espécie canina foram empregadas quatro dietas isonutrientes, contendo uma fonte de parede celular de levedura (PCL), duas fontes de beta-glucano (BG1 e BG2) e uma dieta controle (CT). Foram utilizados 24 cães da raça beagle, adultos, divididos em quatro grupos de seis animais. As dietas foram fornecidas por um período total de 126 dias e as avaliações incluíram hemograma e avaliações bioquímicas, dosagem de anticorpos anti-Leptospira, imunofenotipagem de linfócitos sanguíneos, avaliação da concentração de IgA em fezes, teste de hipersensibilidade cutânea tardia e dosagens de citocinas em sobrenadante de cultura celular. Os animais foram submetidos a desafio antigênico com vacina contra leptospirose no dia 42. Os dados foram avaliados pelo procedimento GLM do SAS, sendo as médias comparadas pelo teste de Tukey (p≤0,1). Nos exames bioquímicos houve discreta variação entre os tratamentos e ao longo dos dias. No hemograma notou-se aumento dos linfócitos para BG2. A dosagem de anticorpos anti-Leptospira, mostrou baixos títulos, não havendo boa resposta à vacinação. A imunofenotipagem revelou um aumento dos linfócitos T totais, T helper, T citotóxicos e linfócitos B no grupo BG2 e de linfócitos T citotóxicos e linfócitos B para o grupo PCL. Apesar da variação da concentração de IgA fecal ao longo dos dias, os tratamentos não influenciaram tais parâmetros. O teste de hipersensibilidade cutânea tardia mostrou um aumento na resposta à inoculação da vacina, para os grupos PCL e BG2. Na dosagem de citocinas em sobrenadante de cultura celular, apenas foi observada diferença na quantificação de TNF-α,... / Some products from the cell wall of the yeast Saccharomyces cerevisiae are known to act on the immunity, however this action, especially of the beta-glucan fraction, has never been demonstrated in dogs. To study these effects on the immunity of dogs four isonutrient diets were made, containing one source of yeast cell wall (YCW), two sources of beta-glucan (BG1 and BG2) and a control diet (CT). 24 adult beagle dogs were used, divided in four groups of six animals. Diets were given for a 126 days period. Evaluations included complete blood count and biochemistry profile, quantification of antibodies against Leptospira, immunophenotyping of blood lymphocytes, IgA concentration in feces, delayed-type hypersensitivity test and quantification of cytokines in cell culture supernatant. Animals were exposed to antigen challenge, by the vaccine against leptospirosis on day 42. Data were analyzed by the GLM procedure of the SAS software and the means were compared by the Tukey test (p<0,01). Biochemistry profile showed slight differences among the groups. A increase in lymphocyte count was observed for BG2 treatment. Quantification of antibodies against Leptospira showed low titles, with poor response to vaccination. Immunophenotyping revealed an increase during the time in total T cells, helper and cytotoxic T cells, and B lymphocytes for BG2 and of cytotoxic T cells and B lymphocytes for YCW group. Despite the variation in fecal IgA concentration during the time, treatments did not influence these parameters. Delayed-type hypersensitivity test showed an increased response to the vaccine inoculation, for YCW and BG2 groups. In the quantification of cytokines in cell culture supernatant the only difference observed was in TNF-α concentration, being BG2 higher than CT. We concluded that both yeast cell wall and beta-glucan fraction act on dogs` immunity
34

Flavonóides e mananoligossacarídeos em dietas para frangos de corte /

Batista, Liliana Soares. January 2005 (has links)
Orientador: Edivaldo Antônio Garcia / Resumo: O experimento foi realizado no setor de avicultura da Faculdade de Medicina Veterinária e Zootecnia, Câmpus de Botucatu, com o objetivo de avaliar os efeitos da inclusão de flavonóides juntamente com mananoligossacarídeos (mos) frente a outros aditivos sobre o desempenho, rendimento da carcaça e de partes e qualidade da carne de frangos de corte criados no período de 1 a 42 dias. Foram utilizados 1500 frangos de corte da linhagem Cobb, distribuídos em um delineamento inteiramente casualizado com cinco tratamentos e seis repetições de 50 aves por parcela, para análise de desempenho nos períodos de 1 - 21, 22 - 42, 22 - 35, 36 - 42 e 1 - 42 dias. Os tratamentos consistiram em antibiótico, probiótico 1, probiótico 2, testemunha e flavonóide + mos. Aos 42 dias foram retiradas 24 aves por tratamento para as análises de rendimento de carcaça, de partes e qualidade de carne. A análise estatística dos dados foi realizada pelo SISVAR (Ferreira, 1998). Não houve diferença significativa entre os tratamentos para ganho de peso diário, consumo de ração, mortalidade, conversão alimentar e peso médio final nos períodos de 1 - 21, 22 - 42, 22 - 35, 36 - 42. No período de 1 - 42 dias também não houve diferença significativa entre os tratamentos para ganho de peso diário, consumo de ração, mortalidade e peso médio final mas houve diferença significativa para conversão alimentar, onde o tratamento flavonóide + mos apresentou o melhor índice. O rendimento de carcaça e de partes não foi alterado significativamente entre os tratamentos. As análises de qualidade de carne para pH e coloração... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The experiment was carried out at the School of Veterinary and Animal Science, FMVZ, Unesp, Botucatu. The study aimed to evaluated to effect of the use of flavonoids + mannan oligosaccharides (mos) and others growth promoters on performance, carcass yield and cuts, meat quality of broilers reared from 1 - 42 days. This experimental design was the completely randomized. One thousand and fifty male Cobb broiler chicks were distributed in five treatment with six replicates of 50 birds each. Growth performance data were obtained from 1 - 21, 22 - 42, 22 - 35, 36 - 42 and 1 - 42 days period. The treatments were denominated as: antibiotic, probiotic 1, probiotic 2, negative control and flavonoids + mos. At 42 days of age, twenty four birds from each treatment were slaughtered to evaluate carcass yield and cuts, and meat quality. Experiment data were calculated and analyzed using SISVAR (Ferreira, 1998). There were no significant effects of treatments on growth performance data were obtained from 1 - 21, 22 - 42, 22 - 35, 36 - 42 days period. In the total period, 1 - 42 days, the results showed that there were no significant of treatment effect on mortality, weight gain, feed consumption, live weight and efficiency production factor but there were significant effect on feed convertion, the treatment flavonoids + mos was better when compared with other treatments. There were no significant effects of treatments on carcass yield, yield cuts, pH and color. There were significant effects of treatments on Tbars (this analysis show the oxidative stability) to breast and thig meat, the treatment flavonoids + mos. was better when compared with other treatments. / Mestre
35

Mannan Molecular Substructures Control Nanoscale Glucan Exposure in Candida

Graus, Matthew S., Wester, Michael J., Lowman, Douglas W., Williams, David L., Kruppa, Michael D., Martinez, Carmen M., Young, Jesse M., Pappas, Harry C., Lidke, Keith A., Neumann, Aaron K. 28 August 2018 (has links)
Cell wall mannans of Candida albicans mask β-(1,3)-glucan from recognition by Dectin-1, contributing to innate immune evasion. Glucan exposures are predominantly single receptor-ligand interaction sites of nanoscale dimensions. Candida species vary in basal glucan exposure and molecular complexity of mannans. We used super-resolution fluorescence imaging and a series of protein mannosylation mutants in C. albicans and C. glabrata to investigate the role of specific N-mannan features in regulating the nanoscale geometry of glucan exposure. Decreasing acid labile mannan abundance and α-(1,6)-mannan backbone length correlated most strongly with increased density and nanoscopic size of glucan exposures in C. albicans and C. glabrata, respectively. Additionally, a C. albicans clinical isolate with high glucan exposure produced similarly perturbed N-mannan structures and elevated glucan exposure geometry. Thus, acid labile mannan structure influences the nanoscale features of glucan exposure, impacting the nature of the pathogenic surface that triggers immunoreceptor engagement, aggregation, and signaling. Graus et al. find that N-mannan structural features regulated by Candida mannosyltransfersases control glucan exposure. Loss of mannan increased the frequency and size of glucan exposures and changed multivalent receptor engagement. Changes to mannan structure in a bloodstream isolate are associated with elevated glucan exposure at the nanoscale.
36

Candida Auris Cell Wall Mannosylation Contributes to Neutrophil Evasion Through Pathways Divergent From Candida Albicans and Candida Glabrata

Horton, Mark V., Johnson, Chad J., Zarnowski, Robert, Andes, Brody D., Schoen, Taylor J., Kernien, John F., Lowman, Douglas, Kruppa, Michael D., Ma, Zuchao, Williams, David L., Huttenlocher, Anna, Nett, Jeniel E. 01 May 2021 (has links)
Candida auris, a recently emergent fungal pathogen, has caused invasive infections in health care settings worldwide. Mortality rates approach 60% and hospital spread poses a public health threat. Compared to other Candida spp., C. auris avoids triggering the antifungal activity of neutrophils, innate immune cells that are critical for responding to many invasive fungal infections, including candidiasis. However, the mechanism underpinning this immune evasion has been largely unknown. Here, we show that C. auris cell wall mannosylation contributes to the evasion of neutrophils ex vivo and in a zebrafish infection model. Genetic disruption of mannosylation pathways (PMR1 and VAN1) diminishes the outer cell wall mannan, unmasks immunostimulatory components, and promotes neutrophil engagement, phagocytosis, and killing. Upon examination of these pathways in other Candida spp. (Candida albicans and Candida glabrata), we did not find an impact on neutrophil interactions. These studies show how C. auris mannosylation contributes to neutrophil evasion though pathways distinct from other common Candida spp. The findings shed light on innate immune evasion for this emerging pathogen. IMPORTANCE The emerging fungal pathogen Candida auris presents a global public health threat. Therapeutic options are often limited for this frequently drug-resistant pathogen, and mortality rates for invasive disease are high. Previous study has demonstrated that neutrophils, leukocytes critical for the antifungal host defense, do not efficiently recognize and kill C. auris. Here, we show how the outer cell wall of C. auris promotes immune evasion. Disruption of this mannan polysaccharide layer renders C. auris susceptible to neutrophil killing ex vivo and in a zebrafish model of invasive candidiasis. The role of these mannosylation pathways for neutrophil evasion appears divergent from other common Candida species.
37

An investigation of the biology and chemistry of the Chinese medicinal plant, Amorphophallus konjac

Yee, Melinda Chua Fui January 2011 (has links)
Konjac glucomannan (KGM), the main biologically active constituent of konjac flour extracted from corms of Amorphophallus konjac (konjac), can be used to prepare functional foods and may also have potential as a pharmaceutical product to combat obesity. The current study employed three experimental approaches to study the biology and chemistry of konjac, namely (1) glasshouse experiments to study the morphogenesis, growth and productivity of konjac plants, (2) a histological and immunocytochemical investigation of the localisation and developmental regulation of the deposition and metabolism of KGM in developing corm tissues, and (3) a comparative study of methodologies for the extraction and analysis of KGM. The current data demonstrated a morphological and functional separation between the ventral and dorsal regions of corms. The ventral region appeared to function as a source during the initial period of shoot development, while the dorsal region appeared to operate as a sink after the development of mature canopy. Once the corm reached maturity, both an inflorescence and a leaf were produced within a single season. It has also been demonstrated that the age of the ‘mother’ corm is an important factor affecting the quality of offsets produced. An anti-mannan antiserum detected a temporally regulated pattern of mannan epitope production within glucomannan idioblasts in developing corm tissues, with increased expression as the corm approached maturity/dormancy. The current observations also suggest that the mobilization of KGM initiates at the periphery of the corm and proceeds inwards towards the centre of the corm. Compositional analysis showed that the purified konjac flour (PKF) produced using a modified extraction procedure contained 92% glucomannan, with a weight average molecular weight (Mw), polydispersity index (PDI) and degree of acetylation (DA) of 9.5 ± 0.6 x 105 gmol-1, 1.2 and 2.8 wt. %. These data, plus Fourier-transform infrared spectral (FTIR) and zero shear viscosity analyses of the extract (PKF) were all consistent with the literature. Comparison of three existing methodologies for the quantitative analysis of the KGM content, namely 3,5-dinitrosalicylic acid (3,5-DNS), phenol-sulphuric acid and enzymatic colorimetric assays; indicated that the 3,5-DNS colorimetric assay was the most reproducible and accurate method, with a linear correlation coefficient of 0.997 and recoveries between 97% and 103% across three spiking levels of starch. In summary, this study has provided a better understanding of aspects of the biology and cultivation of A. konjac and has also produced methodologies which can be used as the basis for an improved good laboratory practice (GLP) for the commercial extraction and analysis of this multifunctional natural polymer.
38

Protinádorová imunoterapie založená na instalaci manózy na povrch nádorových buněk / Anticancer immunotherapy based on the installation of mannose on the surface of tumor cells

MAIEROVÁ, Veronika January 2012 (has links)
The aim of this thesis was to find optimal therapy based on combination of membrane-anchored phagocytic ligands (mannose-(G)5-(K)10-STE, mannan-BAM, mannan-SMCC) with LPS (ligand of signal receptor)for treatment of murine melanoma B16-F10. Mixture of mannan-BAM with LPS applied in pulse regime proved to be the most effective, resulting in heigh reduction of tumor growth and significant prolongation of survival.
39

Životní cyklus volně žijících améb. Diferenciace amfizoických améb rodu Acanthamoeba a Balamuthia / Live cycle of the free-living amoeba. Differentiation of amoebae of the genera Acanthamoeba and Balamuthia

Klieščiková, Jarmila January 2013 (has links)
Free-living pathogenic amoebae Acanthamoeba spp. and Balamuthia mandrillaris are causative agents of important diseases of human: rarely occurring but highly fatal granulomatous amoebic encephalitis (both) and keratitis (Acanthamoeba). One of the reasons for the problematic therapy is differentiation into highly resistant cysts often found in affected tissues. In our study we have found that correct encystation in Acanthamoeba requires apart from others, the presence of functioning Golgi apparatus transporting the cyst wall material to the cell surface; glycogen phosphorylase degrading glycogen into glucose which seems to be further used for cellulose synthesis and two non-constitutive cellulose synthases. Acanthamoeba cellulose synthases seem not to be inhibited by known herbicides. In the cyst wall of acanthamoebae we detected cellulose, -mannan, and -1, 3-1, 4-linked glucan [lichenin or mixed-linkage glucan (MLG)]. Cellulose is present in the inner (endocyst) and the outer (exocyst) layers of the cyst wall, whereas-mannan and MLG are found in the endocyst. In a protozoan organism, MLG was detected for the first time. The MLG of Acanthamoeba has a similar composition to that found in barley with high amount of cellobiosyl and cellotriosyl followed by cellotetraosyl units. In contrast, with...
40

Funkcionalizované hybridní polymerní struktury pro biomedicínské aplikace / Functionalized hybrid polymer structures for biomedical applications

Rabyk, Mariia January 2018 (has links)
This doctoral thesis is dedicated to the synthesis and characterization of novel functionalized hybrid structures for biomedical purposes. Systems reported in this work can be subdivided into the two main groups: natural-based materials and synthetic amphiphilic block copolymers. Both groups were studied as perspective theranostic agents for medical applications. In the first group, natural polysaccharides glycogen and mannan were selected as starting materials for preparation of novel nanoconjugates that possess ability for multimodal detection in vivo. Because grafting of natural macromolecules with synthetic polymers generally slows down the biodegradation rate, both polysaccharides were modified in two different ways to form nanoprobes with or without poly(2-methyl-2-oxazoline)s chains. The prepared nanoconjugates were functionalized with N-hydroxysuccinimide-activated fluorescence and magnetic resonance imaging labels. The resulting materials were tested both in vitro and in vivo and were shown to be completely biocompatible, biodegradable and exhibit some extra benefits in terms of their practical usage in biomedicine. Glycogen was functionalized with allyl and propargyl groups with following freeze-drying from aqueous solutions to form nano- and microfibrous materials. The presence of both...

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