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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

Generation of isogenic pluripotent stem cell lines for study of APOE, an Alzheimer’s risk factor

January 2017 (has links)
abstract: Alzheimer’s disease (AD), despite over a century of research, does not have a clearly defined pathogenesis for the sporadic form that makes up the majority of disease incidence. A variety of correlative risk factors have been identified, including the three isoforms of apolipoprotein E (ApoE), a cholesterol transport protein in the central nervous system. ApoE ε3 is the wild-type variant with no effect on risk. ApoE ε2, the protective and most rare variant, reduces risk of developing AD by 40%. ApoE ε4, the risk variant, increases risk by 3.2-fold and 14.9-fold for heterozygous and homozygous representation respectively. Study of these isoforms has been historically complex, but the advent of human induced pluripotent stem cells (hiPSC) provides the means for highly controlled, longitudinal in vitro study. The effect of ApoE variants can be further elucidated using this platform by generating isogenic hiPSC lines through precise genetic modification, the objective of this research. As the difference between alleles is determined by two cytosine-thymine polymorphisms, a specialized CRISPR/Cas9 system for direct base conversion was able to be successfully employed. The base conversion method for transitioning from the ε3 to ε2 allele was first verified using the HEK293 cell line as a model with delivery via electroporation. Following this verification, the transfection method was optimized using two hiPSC lines derived from ε4/ε4 patients, with a lipofection technique ultimately resulting in successful base conversion at the same site verified in the HEK293 model. Additional research performed included characterization of the pre-modification genotype with respect to likely off-target sites and methods of isolating clonal variants. / Dissertation/Thesis / Masters Thesis Bioengineering 2017
12

Variações alélicas que afetam a carotenogênese em tomateiro alteram o amadurecimento e a suscetibilidade dos frutos ao fungo Botrytis cinerea / Allelic variations affecting tomato carotenogenesis alter ripening and susceptibility of fruits to Botrytis cinerea

Bruna Orsi 05 July 2018 (has links)
Carotenoides são pigmentos encontrados em grande abundancia em frutos do tomateiro. A capacidade de sequestro de radicais destes pigmentos faz do tomate uma excelente opção para inclusão de compostos nutricionais pela dieta. Embora a síntese de carotenoides seja reconhecida como uma das respostas da cascata de eventos que levam ao amadurecimento, pouco se sabe a respeito de sua influência neste processo. Deste modo, o objetivo deste trabalho foi determinar se o conteúdo e a composição de carotenóide nos frutos acarretam alterações na conservação e na suscetibilidade dos frutos ao fungo B. cinerea. Foram utilizadas linhagens quase isogênicas (NILs) ao Micro Tom (MT) carregando as mutações, Beta carotene (B), tangerine (t), yellow flesh (r) e Delta carotene (Del). A caracterização dessas variações alélicas revelou, não apenas alterações no conteúdo de carotenoides, mas também outros efeitos pleiotrópicos relacionados ao amadurecimento, parâmetros de qualidade, espessura da cutícula e propriedades nutricionais dos frutos. Em face disso, subsequentemente investigamos se o diferencial conteúdo e composição de carotenóides nas referidas NILs altera a suscetibilidade dos frutos ao fungo Botrytis cinerea. A caracterização do amadurecimento demonstrou que o pico climatérico dos frutos do mutante r foi antecipado, assim como a transição para o estádio breaker. De modo contrário, a alteração na coloração da epiderme do mutante t foi atrasada, reafirmando suspeitas de outros autores que sugeriram que a enzima carotenoide-isomerase é necessária para a síntese de carotenoides no escuro. O conteúdo de ácido ascórbico também foi contrastante entre estes genótipos, sendo que no mutante r a sua concentração foi elevada, enquanto em t sua concentração foi reduzida. A perda de massa dos frutos foi menor no mutante Del, no entanto, esta característica não esteve relacionada a espessura da cutícula, que foi maior em B. A inoculação com B. cinerea por meio de ferimentos na pele dos frutos revelou menor suscetibilidade do mutante t, e em menor amplitude, do mutante Del. Ainda, o mutante t também se mostrou menos suscetível à inoculação do patógeno sobre frutos intactos. A maior espessura da cutícula de B não reduziu sua suscetibilidade ao fungo, que infectou os tecidos preferencialmente através da cicatriz do pedúnculo. A interação com B. cinerea desencadeou a produção de etileno e de espécies reativas de oxigênio (EROs), assim, é provável que a capacidade de sequestro de radicais livres tenha contribuído para a redução da suscetibilidade em t e Del, que mostraram menor produção de superóxido. Juntos, estes resultados sugerem que a modulação na atividade de enzimas da carotenogênese pode servir como ferramenta para obtenção de frutos com diferente vida útil durante o armazenamento pós-colheita de tomate. / Carotenoids are pigments found in great abundance in tomato fruits. The radical sequestration capacity of these pigments makes tomato an excellent option for inclusion of nutritional compounds in diet. Although the synthesis of carotenoids is recognized as one of the cascade responses that trigger ripening, little is known about its influence in this process. Thus, the aim of this study was to determine if the content and composition of carotenoids in the fruits alters the conservation and the susceptibility of the fruits to the B. cinerea fungus. Micro Tom (MT) near-isogenic lines (NILs) harboring the mutations Beta carotene (B), tangerine (t), yellow flesh (r) and Delta carotene (Del) has been used. The characterization of these allelic variations revealed not only changes in the carotenoid content but also other pleiotropic effects related to maturation, quality parameters, cuticle thickness and nutritional properties of fruit. In this way, we subsequently investigated whether the differential content and composition of carotenoids in NILs alters fruit susceptibility to the fungus Botrytis cinerea. The ripening characterization showed that the climacteric peak of the fruits of the r mutant was anticipated, as well as the transition to the breaker stage. Conversely, the change in epidermal coloration of mutant t was delayed, reaffirming suspicions of other authors who suggested that the carotenoid-isomerase enzyme is required for the synthesis of carotenoids in the dark. The ascorbic acid content was also contrasting among these genotypes, and in the r mutant its concentration was high, while at t its concentration was reduced. The fruit mass loss was lower in Del mutant, however, this characteristic was not related to cuticle thickness, which was higher in B. Wound-inoculation with B. cinerea revealed less susceptibility of the mutant t, and in a lesser extent, the mutant Del. Further, mutant t was also less susceptible to pathogen inoculation on intact fruits. The greater thickness of the cuticle of B did not reduce its susceptibility to the fungus, which infected the tissues preferentially through the scar of the peduncle. The interaction with B. cinerea triggered the production of ethylene and reactive oxygen species (ROS), so the free radical scavenging capacity probably contributed to the reduction of t and Del susceptibility, which showed lower production of superoxide. Together, these results suggest that modulation in carotenogenesis enzyme activity may serve as a tool to obtain fruit with different shelf-life during post-harvest tomato storage.
13

Régulation de l'agressivité tumorale mammaire par la protéine tyrosine phosphatase PTPL1/PTPN13 / The regulation of breast tumor aggressiveness by Protein Tyrosine Phophatase PTPL1/PTPN13

Hamyeh, Mohamed 03 October 2016 (has links)
Le cancer du sein est un problème majeur de santé public dont l'incidence est en permanente augmentation. La mortalité est le plus souvent due aux métastases. Les études concernant PTPL1, la plus grande des tyrosines phosphatases cytoplasmiques, ont montré que PTPL1 présente les caractéristiques de suppresseur de tumeur. PTPL1 se trouve mutée dans plusieurs types de cancers et son expression est un marqueur de bon pronostique dans les tumeurs mammaires. Mon laboratoire a également montré que PTPL1 participe à l'effet pro-apoptotique des anti-oestrogènes dans les cellules tumorales hormono dépendantes en déphosphorylant IRSl, le substrat d'IGF1-receptor freinant ainsi la voie PI3K/AKT. PTPL1 régule également la croissance, l'invasion et l'adhésion dans les cellules cancéreuses mammaires peu agressives MCF7.Nous avons établi un modèle cellulaire de clones isogéniques capables d'exprimer PTPL1 ou ses mutants d'une manière inductible dans les cellules cancéreuses mammaires invasives MDA-MB-231. D’une part, nous avons montré un impact négatif de l'expression de PTPL1 sur le phénotype invasif de ces cellules. D'une manière intéressante, le mutant catalytiquement inactif a montré un comportement similaire à celui du contrôle de transfection. Ceci montre l'importance de l'activité catalytique de PTPL1 dans l'inhibition du phénotype agressif. Nous testons maintenant in vivo la tumorigenicité des clones chez les souris athymique.D'autre part, nous avons étudié par protéomique comparative (SILAC) la tyrosine phosphorylation globale des protéines cellulaires dans les cellules MCF-7 et MDA-MB-231 exprimant ou non PTPL1. Parmi les protéines identifiées nous retrouvons des acteurs des différentes voies de signalisations connues dans la littérature pour être impactées par PTPL1 , mais de manière remarquable plus du quart des protéines identifiées sont liées aux jonctions cellulaires ou à leur régulation. Nous avons donc étudié l'effet de la phosphatase sur les jonctions cellulaires et montré que la surexpression de PTPL1 favorise la formation d'agrégats cellulaire en culture 3D, augmente la stabilité des contacts cellulaire en vidéo-microscopie, relocalise la desmogléïne aux jonctions cellulaires et induit une réexpression de la E cadhérine aux niveau du contact cellule/cellule dans les cellules MDA-MB-231.Les jonctions et la polarité cellulaires sont très importantes en cancérologie en particulier dans le processus invasif qui est la première étape de la dissémination métastatique donc il serait maintenant important d'identifier les substrats directs de PTPL1 pour élucider la signalisation de PTPL1 vers les jonctions et proposer de nouvelles cibles thérapeutique. / The regulation of breast tumor aggressiveness by Protein Tyrosine Phosphatase PTPL1/ PTPN13Breast cancer is a major problem for public health of which the incidence continues to increase. Its mortality is often linked to metastasis formation. Studies on PTPL1, the largest protein tyrosine phosphatase, have shown that it presents the characteristics of a tumor suppressor gene. PTPL1 is mutated in several types of cancers and its expression is associated with good prognostic in prostate and breast cancers. My team has shown that PTPL1 mediates the pro apoptotic effect of anti-estrogen in hormone-sensitive tumor cells by dephosphorylating IRS1, Insulin growth factor-1 receptor substrate, thus blocking PI3K/Akt pathway. In addition, PTPL1 regulates the growth, the invasion, and the adhesion of low aggressive breast tumor cells MCF-7.Our team established an isogenic cellular model capable of expressing PTPL1 or its mutants (phosphatase-dead and substrate-trapping mutants) in an inducible fashion in invasive cells. We showed that functional PTPL1 expression has a negative impact on cell aggressive phenotypes. Interestingly, the phosphatase-dead mutant exhibits the same behavior as the transfection control. This evidences that PTPL1 activity is crucial for the inhibition of aggressiveness. We are currently testing the clones tumorigenicity in athyemic mice.Furthermore, we conducted a comparative proteomic (SILAC) in order to study the global tyrosine phosphatome in MCF-7 and MDA-MB-231 cells with or without PTPL1. Our findings suggest that PTPL1 regulates the phosphorylation of proteins involved in different signaling pathways already described in the literature to be impacted by PTPL1. Remarkably, the quarter of proteins identified belong to cell junction structure or regulation. We then studied the impact of this phosphatase on cell junctions and showed that PTPL1 overexpression enhances cell aggregate formation in 3D culture, increases cell contact stability, relocates desmoglein to the cell junctions, and induces E-cadherin re-expression at the level of cell-cell contacts in MDA-MB-231 cells.Cell junctions and polarity are very important in oncology and particularly in the invasive process which is the first step in the metastatic dissemination. Our ongoing work focuses on identifying direct substrates for PTPL1 in order to elucidate the underlying PTPL1 signal leading to cell junctions and consequently propose a novel therapeutic targets.
14

The role of LC and FAS in regulating floral meristem and fruit locule number in tomato

Chu, Yi-Hsuan January 2017 (has links)
No description available.
15

Resposta tecidual após implante subcutâneo de diferentes cimentos à base de ionômeo de vidro / Tissue response after subcutaneous implantation of different glass ionomer based cements

Borges, Luã Lopes 19 July 2018 (has links)
O Cimento de Ionômero de Vidro (CIV) é um material restaurador utilizado na Odontologia Minimamente Invasiva pois, além de apresentar propriedade adesiva à estrutura dental, apresenta propriedades tais como liberação e absorção de íons flúor, compatibilidade biológica com os tecidos bucais e coeficiente de expansão térmica similar ao da dentina. No entanto, o CIV apresenta baixa resistência mecânica, alta suscetibilidade à perda e ao ganho de água nas primeiras 24 horas (sinérese e embebição), período prolongado de presa e polimento ruim. Apesar desse material ter sido introduzido na Odontologia há mais de 40 anos, sua fórmula original vem sofrendo alterações, com o objetivo principal de aprimorar as propriedades mecânicas e alcançar melhores resultados clínicos. Dentre os CIV convencionais, destaca-se o EQUIA&reg; Forte Fil (GC Corporation, Tokyo, Japan), material elaborado com o objetivo de aprimorar as características físicas e estéticas do seu antecessor EQUIA&reg; Fil. No entanto, até o momento não existem trabalhos biológicos avaliando o desempenho do EQUIA&trade; Forte e Ketac&trade; Universal Aplicap&trade;. O objetivo deste estudo foi avaliar a resposta do tecido conjuntivo subcutâneo de camundongos isogênicos após implante de diferentes cimentos de ionômero de vidro (EQUIA&reg; Forte Fil, EQUIA&reg; Fil e Ketac&trade; Universal Aplicap&trade;). Foram utilizados 87 camundongos isogênicos da linhagem BALB/c divididos em 12 grupos, sendo 9 experimentais (Ketac, E. Fil e E. Forte nos períodos de 7, 21 e 63 dias) e 3 controles (tubos de polietileno vazios, nos mesmos períodos). Decorridos os períodos experimentais, a porção do tecido conjuntivo subcutâneo circundante ao material implantado foi removida e submetida ao processamento histotécnico e à coloração com hematoxilina e eosina. Foi realizada a descrição da reação tecidual em contato com cada material, análise semi-quantitativa do fibrosamento e do infiltrado inflamatório e análise quantitativa da espessura do tecido reacional granulomatoso em contato com o material testado ou tubo de polietileno. Os dados foram analizados estatisticamente (&alpha;=0,05), utilizando o teste de Kruskal-Wallis, seguido pelo Pós-teste de Dunn. Inicialmente, o fibrosamento não foi diferente entre os materiais testados (p>0,05), porém passou a ser diferente aos 21 dias, com o controle apresentando o estágio mais avançado de fibrosamento, e chegando ao final do experimento com o Grupo EQUIA&reg; Forte Fil com estágio mais avançado de fibrosamento, em comparação ao grupo EQUIA&reg; Fil (p<0,05). O infiltrado inflamatório, por sua vez, não apresentou diferença entre os materiais testados ao longo dos períodos experimentais (p>0,05). A área do tecido reacional granulomatoso foi maior para o Grupo E. Forte, diferindo do controle em todos os períodos avaliados (p<0,05). De acordo com os resultados obtidos, concluiu-se que todos os cimentos à base de ionômero de vidro testados apresentaram compatibilidade tecidual, de acordo com os diferentes parâmetros avaliados / The Glass Ionomer Cement (GIC) is a restorative material used in Minimally Invasive Dentistry. Besides it presenting adhesive properties to the dental structure, GIC has properties such as release and absorption of fluoride ion, biological compatibility with buccal tissues and expansion coefficient similar to that of dentin. However, GIC presents low mechanical resistance, high susceptibility to loss and water gain in the first 24 hours (syneresis and imbibition), prolonged setting time and poor polishing. Although this material was introduced in Dentistry more than 40 years ago, its original formula has undergone changes, with the main objective of improving the mechanical properties and achieving better clinical results. Among the conventional GIC, we highlight EQUIA&reg; Forte Fil, a material developed with the aim of improving the physical and aesthetic characteristics of its predecessor EQUIA&reg; Fil. However, there are no biologic researches evaluating the performance of EQUIA&reg; Forte and Ketac&trade; Universal Aplicap&trade;. The aim of this study was to evaluate the subcutaneous connective tissue response of isogenic mice after implanting different glass ionomer cements (EQUIA&reg; Forte Fil, EQUIA&reg; Fil and Ketac&trade; Universal Aplicap&trade;). Eighty-seven isogenic mice of the BALB/c were divided into 12 groups, 9 were experimental (Ketac, E. Fil and E. Forte at 7, 21 and 63 days) and 3 controls (empty polyethylene tubes at the same experimental time). After the experimental periods, the portion of the subcutaneous connective tissue surrounding the implanted material was removed and subjected to histotechnical processing and staining with hematoxylin and eosin. A description of the tissue reaction in contact with each material, semi-quantitative analysis of f collagen fiber formation and inflammatory infiltrate and quantitative analysis of the tissue thickness of the granulomatous reaction tissue in contact with the tested material or polyethylene tube were performed. Data were analyzed statistically (&alpha;=0.05) using the Kruskal-Wallis test, followed by the Dunn Post test. Initially, the collagen fiber formation was not different between the tested materials (p>0.05), but it became different at 21 days, with the control presenting the most advanced stage of collagen fiber formation, and reaching the end of the experiment with the EQUIA&reg; Forte Fil group with a more advanced stage of collagen fiber formation, compared to the EQUIA&reg; Fil group (p<0.05). Inflammatory infiltrate, on the other hand, showed no difference between the materials tested during the experimental periods (p>0.05). The tissue thickness was larger for the EQUIA&reg; Forte Fil group, differing from the control group in all evaluated periods (p<0.05). According to the results obtained, it was concluded that all the glass ionomer - based cements tested showed tissue compatibility, according to the different parameters evaluated
16

Protein composition-functionality relationships using novel genetic lines

Jonnala, Ramakanth S January 1900 (has links)
Doctor of Philosophy / Department of Grain Science and Industry / Finlay I. MacRitchie / Novel genetic materials were used to deduce gluten protein composition-functionality relationships. The Pegaso bread wheat near-isogenic lines (NILs) included addition, variation and/or deletion of major loci coding for HMW-GS, LMW-GS and gliadins. The waxy wheat lines (Svevo and N11 set) included wild, partial and complete waxy lines. Triticale translocations include 1R.1D and 1A.1D lines (GDS7, Trim, Rhino and Rigel sets) with HMW-GS 5+10 and 2+12. The main goal of the study was to establish the usefulness of NILs as appropriate materials to investigate the structure-function relationships of wheat proteins and to evaluate the performance of unique triticale translocations and waxy wheat lines. Effect of genetic variation on phytochemical (phenolic acid and policosanol) contents was also studied. Innovative methods like MALLS, Lab-on-a-chip and micro (10 g) baking were utilized along with traditional analytical methods. Results confirmed the potential of using NILs in understanding the effects of certain proteins coded at specific loci that might often be targeted in breeding programs. Removal of expected chain terminators at Gli-1/Gli-2 loci causes a shift in MWD to higher values, reflected in higher UPP and dough strength. Lines with HMW-GS 5+10 were clearly separated from 2+12 lines in terms of dough strength and UPP. The present study obtained evidence that modified ω-gliadins acts as chain terminators and cause reduction of protein polymer size and thus shifts in MWD. Marked differences in terms of milling characteristics, protein composition and ultimately in end-use functionality were observed with various waxy wheat null lines. Loaf volumes with waxy wheat flour alone were higher than a 50% blend with commercial wheat; however, breads were unacceptable to consumers in all aspects. Poor milling quality, very low mixing times with low bread loaf volumes were typical of all the triticales studied. However, translocation of the HMW-GS from wheat chromosome 1D increased dough strength, particularly the HMW-GS 5+10. Among the phytochemicals studied, double nulls at Gli-1 loci of Pegaso NILs had the highest total policosanols and total phenolic acid contents.Slight variation to wheat phenolic acid composition and contents were observed with waxy wheat and triticale lines.
17

Aphid-induced transcriptional regulation in near-isogenic wheat

Van Eck, Leon 15 July 2007 (has links)
This study represents the first comprehensive analysis of gene regulation underlying the distinct categories of resistance afforded to wheat (Triticum aestivum, L.) by different Dn genes. Russian wheat aphid (Diuraphis noxia, Mordv.) feeding on susceptible wheat cultivars causes leaf rolling, chlorosis and the eventual death of the plant. Plants expressing Dn genes are resistant to D. noxia infestation, but different Dn genes afford phenotypically distinct modes of resistance: the Dn1 gene confers an antibiotic effect to lower aphid fecundity; Dn2 confers tolerance to high aphid pressure; and Dn5 confers antixenosis, and aphids do not prefer such plants as hosts. Little is known about the components involved in establishing a successful defence response against D. noxia attack and how these differ between the distinct resistance categories. It is assumed that the Dn genes function as classic R genes in plant defence, being receptors for elicitors in aphid saliva. Upon recognition, defence response signalling is initiated, but the exact mechanics of subsequent cellular events in aphid resistance have only recently come under investigation. Evidence from cDNA microarray and subtractive hybridization experiments indicated the involvement of kinase signalling cascades and photosynthetic proteins in the response against D. noxia. However, expression analysis describing how these processes differ between plants carrying different Dn genes and how these differences account for antibiosis, antixenosis or tolerance had not been conducted. We consequently investigated the downstream components involved in or affected by the generation of these resistance mechanisms by comparing the responses in transcript regulation of Tugela near-isogenic lines with different Dn genes to D. noxia infestation. cDNA-AFLP analysis was selected as an appropriate functional genomics tool, since it is semi-quantitative, does not require prior sequence information and allows for the discovery of novel genes. cDNA-AFLP analysis yielded 121 differentially regulated transcript-derived fragments (TDFs) grouped into eight expression clusters. We cloned and sequenced 49 representative TDFs, which were further classified into five broad functional categories based on inferred similarity to database sequences. Transcripts involved in such diverse processes as stress, signal transduction, photosynthesis, metabolism and gene regulation were found to be differentially regulated during D. noxia feeding. Many TDFs demonstrated homology to proteins with unknown function and several novel transcripts with no similarity to previously published sequences were also discovered. Detailed expression analysis using quantitative RT-PCR and RNA hybridization provided evidence that the time and intensity of induction of specific pathways is critical for the development of a particular mode of resistance. This includes: the generation of kinase signalling cascades and the induction of several ancillary processes such as ubiquitination, leading to a sustained oxidative burst and the hypersensitive response during antibiosis; tolerance as a passive resistance mechanism countering aphid-induced symptoms through the repair or de novo synthesis of photosystem proteins; and the possible involvement of ethylene-mediated wounding pathways in generating volatile organic compounds during antixenosis. This is the first report on the involvement of KCO1, a vacuolar K+ channel, in assisting cytosolic Ca2+-influx and preventing leaf rolling, as well as on the role of iron homeostasis as a gene regulatory mechanism for sustaining the oxidative burst during the antibiotic defence response. This study opens up several areas of investigation heretofore unexplored in cereal-aphid interaction research. Of particular interest is the induction of genes involved in photosynthetic compensation during Dn2 tolerance responses, since these constitute a novel, passive resistance mechanism exclusive to aphid defence as opposed to the active resistance triggered in the presence of the Dn1 gene in the form of a general hypersensitive response. / Dissertation (MSc)--University of Pretoria, 2008. / Genetics / unrestricted
18

Synergistic gene editing in human iPS cells via cell cycle and DNA repair modulation / 細胞周期およびDNA修復調節を介したヒトiPS細胞における相乗的遺伝子編集

Maurissen, Thomas Luc 27 July 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医科学) / 甲第22700号 / 医科博第115号 / 新制||医科||8(附属図書館) / 京都大学大学院医学研究科医科学専攻 / (主査)教授 遊佐 宏介, 教授 近藤 玄, 教授 齊藤 博英 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
19

Paracoccidioidomicose: acompanhamento de parâmetros de imunidade adquirida e do estado de ativação de fagócitos em camundongos isogênicos suscetíveis submetidos à terapia antifúngica. / Paracoccidioidomycosis: follow up of acquired immunity parameters and of the activation state of phagocytes in susceptible isogenic mice submitted to the antifungal therapy.

Oliveira, Renata Scavone de 20 May 2009 (has links)
Os efeitos da administração de anfotericina B a camundongos suscetíveis ao P. brasiliensis foram avaliados. A L-AmB reverte o padrão de suscetibilidade para o de resistência de forma mais eficiente do que a c-AmB, como observado na quantificação de UFC, NO e IgG2b. Porém, os níveis de TNF-a, IL-12, IFN-g, GM-CSF, IgG total, IgM, IgG1, IgG2a e IgA não são significativamente alterados. Neutrófilos e macrófagos peritoneais co-cultivados com Pb e L-AmB tendem a apresentar maior capacidade fungicida, mas não maior síntese de mediadores. O melhor desempenho de L-AmB poderia se dever a sua interação com TLR4. Em TLR4-deficientes ou não, a progressão da doença é similar. A eficácia da terapia, porém, é menor nos deficientes, como observado na quantificação de UFC; os perfis leucocitários e as concentrações de NO, TNF-a, IL-12 e GM-CSF não são significativamente alterados. Logo, a droga é capaz de reverter os parâmetros micológicos, mas não os imunológicos. A interação entre TLR4, P. brasiliensis e L-AmB não parece ser importante para o estabelecimento da imunidade. / Amphotericin B effects in mice susceptible to P. brasiliensis were evaluated. L-AmB reverts the susceptibility pattern to the resistant one with more efficiency than c-AmB, as confirmed by the CFU, NO e IgG2b quantifications. However, TNF-a, IL-12, IFN-g, GM-CSF, total IgG, IgM, IgG1, IgG2a and IgA levels are not significantly altered. Neutrophils and macrophages cocultivated with Pb e L-AmB tend to present higher fungicidal ability, but not enhanced synthesis of mediators. The better performance of L-AmB could be due to its interaction with TLR4. In TLR4-deficient or sufficient mice, progression of the disease is similar. The efficiency of the therapy, however, is lower in deficient animals, as seen on CFU; leukocyte profiles and NO, TNF-a, IL-12 and GM-CSF levels are not significantly altered by L-AmB-TLR4 interaction. Therefore, the drug administration is capable of reverting mycological parameters, but not the immunological ones. Interaction between TLR4, P. brasiliensis and L-AmB does not seem to play a special role in the establishment of immunity.
20

aPDT: fotossensibilizadores e tempos de exposição de luz não inluenciaram na resposta tecidual de camundongos isogênicos / aPDT: Photosensitizers and light exposure times do not affect the tissue response of isogenic mice

Oliveira, Daniela Silva Barroso de 22 September 2016 (has links)
O objetivo deste estudo foi avaliar a resposta do tecido conjuntivo subcutâneo de camundongos isogênicos após o uso da Terapia Fotodinâmica antimicrobiana (aPDT), utilizando dois fotossensibilizadores, Derivado fenotiazínico (Helbo Blue) e Curcumina, em diferentes tempos de aplicação de lasers (30 segundos, 1 minuto ou 2 minutos). Foram utilizados 141 camundongos isogênicos da linhagem BALB/c cujo tecido conjuntivo subcutâneo foi exposto aos dois fotossensibilizadores, e em seguida irradiado com laser diodo no grupo do Derivado Fenotiazínico e ao LED no grupo da Curcumina. Para cada fotossensibilizador foram utilizados três tempos de irradiação: 30 segundos, 1 minuto e 2 minutos. Ao final de cada um dos períodos experimentais (7, 21 e 63 dias), uma porção do tecido conjuntivo subcutâneo da área do centro da área em que foi aplicada a aPDT foi removida e submetida ao processamento histotécnico de rotina. Foi realizada a descrição do processo inflamatório de forma qualitativa e semi-quantitativa (por meio de escores). Adicionalmente, foi realizada a marcação imunohistoquímica para neutrófilos e macrófagos. Os dados numéricos foram analisados por meio do programa estatístico Sigma Plot 12.0®, utilizando o teste não paramétrico de Kruskal-Wallis, seguido pelo Pós-teste de Dunn, quando houve diferença significativa entre os grupos. O nível de significância adotado foi de 5%. Foi possível observar que, com relação aos parâmetros fibrosamento, espessura e infiltrado inflamatório, no período inicial de 7 dias, as alterações teciduais foram pequena magnitude. No período de 21 dias, apenas o parâmetro infiltrado inflamatório apresentou pequenas variações entre os grupos. No período final de 63 dias, a compatibilidade tecidual foi observada para os dois fotossensibilizadores (Derivado Fenotiazínico e Curcumina) que não apresentaram diferenças significativas nos parâmetros avaliados, independentemente do tempo de aplicação do laser. / The aim of this study was to evaluate the response of subcutaneous connective tissue of isogenic mice after Antimicrobial Therapy (aPDT), using two photosensitizers, Phenothiazine Derivative (Helbo Blue) and Curcumin, at different laser application times (30 seconds, 1 minute or 2 minutes). One hundred and forty one (141) BALB/c isogenic mice were used, which had the subcutaneous connective tissue exposed to the two photosensitizers, followed by irradiation with laser diode to the Phenothiazine derivatives group, and LED to the Curcumin group. Three irradiation times were used to each photosensitizer: 30 seconds, 1 minute and 2 minutes. At the end of each experimental period (7, 21 and 63 days), a sample of the subcutaneous connective tissue, was collected and histotechnical processing was performed. Inflammatory process was described by qualitative and semi-quantitative analysis, using scores. Additionally, immunohistochemical technique was performed to identify neutrophils and macrophages. Data obtained was analyzed by the statistical program Sigma Plot 12.0®, using the non-parametric Kruskal-Wallis test, followed by the Dunn\'s post-test, when significant difference was found between groups. The significance level adopted was 5%. It was also possible to observe that, in relation with the parameters: fiber collagen formation, tissue thickness and inflammatory infiltrate, at the initial period of 7 days, the tissue alteration were of small significance (p<0.05). At 21-days period, only the inflammatory infiltrate parameter presented variation between groups (p<0.05). In the later time point of 63 days, it was observed tissue compatibility regarding the two photosensitizers (Phenothiazine Derivative and Curcumin) with no differences in the evaluated parameters or the laser application times.

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