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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.
171

Efeito do inibidor  de proteinase de origem vegetal EcTI, sobre a inflamação pulmonar alérgica crônica em camundongos Balb/c / Effect of proteinase inhibitor of plant origin EcTI in an experimental model of chronic allergic pulmonary inflammation in Balb/c mice

Adriana Palmeira Dias Rodrigues 21 March 2016 (has links)
INTRODUÇÃO: A prevalência de asma tem crescido e a maioria dos pacientes com asma grave não obtém o controle total dos sintomas com as terapias disponíveis, fazendo-se necessária a busca por novas alternativas terapêuticas. Inibidores de proteinases têm sido estudados como tratamento de processos inflamatórios, dentre eles o Enterolobium contortisiliquum Tripsin Inhibitor (EcTI) OBJETIVO: Avaliar se o inibidor de proteinase EcTI modula a hiperresponsividade brônquica à metacolina, inflamação, remodelamento e estresse oxidativo nas vias aéreas e septos alveolares em um modelo experimental de inflamação pulmonar alérgica crônica. MÉTODOS: Vinte e quatro camundongos Balb/c machos, entre seis e sete semanas de vida, pesando em media 25 g foram divididos em quatro grupos: C (controle), OVA (sensibilizados com ovalbumina, 50 ug intraperironeal (i.p) nos dias 0 e 14 e desafiados nos dias 22, 24, 26, 28); C+EC (controle tratados com EcTI (2 mg/kg/i.p) nos dias 22 a 28); OVA+EC (sensibilizados e desafiados com ovalbumina e também tratados com EcTI (2 mg/kg -i.p) nos dias 22 a 28). No dia 29, foram realizadas realizadas: (i) hiperresponsividade à metacolina e obtidas as respostas máximas de resistência e elastância do sistema respiratório; (ii) análise histopatológica do pulmão para quantificação de eosinófilos, fibras colágenas e elásticas nas vias aéreas (VA) e nos septos alveolares (SA); e (iii) imunohistoquímica para quantificação de células positivas para IFN-y, IL-4, IL-5, IL-13, MMP-9, TIMP-1, TGF-beta, iNOS, NF-kB e fração de volume de isoprostano nas VA e nos SA. Uma semana após o dia 29 foi realizada a técnica de anafilaxia cutanea passiva(PCA) para quantificar IgE e IgG1. A significância foi considerada quando p < 0,05. RESULTADOS: Houve aumento de todos os parâmetros avaliados no grupo OVA em relação ao grupo controle (p < 0,05). Houve atenuação da resposta máxima de Rrs e Ers no grupo OVA+EC comparado as grupo OVA (p < 0,05). O tratamento com EcTI nos animais sensibilizados atenuou o número de eosinófilos, células positivas para IL-4, IL-5, IL-13,IFN-y, iNOS, MMP-9, TIMP-1, NF-kB e TGF-beta e fração de volume de isoprostano, fibras colágenas e elásticas nas vias aéreas e nos séptos alveolares quando comparado ao grupo OVA (p < 0,05).Houve reaçao de PCA nos animais sensibilizados com ovalbumina. CONCLUSÃO: EcTI atenuou a hiperresponsividade brônquica, a inflamação, o remodelamento e o estresse oxidativo nesse modelo experimental de inflamação pulmonar alérgica crônica. Embora sejam necessários mais estudos, esse inibidor pode ser considerado uma futura ferramenta farmacológica para o tratamento de asma / BACKGROUND: The number of cases of asthma has grown in recent decades. People who have severe asthma are likely to have more attacks and are at greater risk of a fatal attack, which propose to keep up global attention and keep approaching for advances in asthma care. Proteinase inhibitors of vegetable origin have been studied as a modulator of inflammatory responses and diseases. Among these inhibitors is Enterolobium contortisiliquum Trypsin Inhibitor (EcTI). AIMS: To evaluate the effects of EcTI in pulmonary mechanical, eosinophilic recruitment, inflammatory cytokines, remodeling of extracellular matrix and oxidative stressin an experimental model of chronic allergic pulmonary inflammation. METHODS: Twenty-four young adult male pathogen-free mice BALB/c (6-7 weeks old, 25-30g) were divided into 4 groups: C (control), OVA (sensitized with ovalbumin, 50 ug intraperitoneal (i.p), on days 0 and 14 and challenged with ova 1%, on days 22, 24, 26, 28); C+EC (control treated with EcTI- 2 mg/kg/i.p. from days 22 to 28); OVA+EC (sensitized and challenged with ovalbumin and treated with EcTI (2 mg/kg/i.p) from days 22 to 28). At day 29, we performed: (i) Bronchial hyperresponsiveness to methacholine and obtained the maximum response of resistance (Rrs) and elastance (Ers) of the respiratory system; (ii) lung histopathological analysis by morphometry to quantify eosinophils, collagen and elastic fibers volume fraction in airways; and (iii) immunohistochemistry to quantify IFN-y, IL-4, IL-5, IL-13, MMP-9, TIMP-1, TGF-, iNOS, NF-kB positive cells and isoprostane volume fraction in airways. One week after the day 29 we performed PCA technique to quantify IgE and IgG1 antibodies. Significance was considered at p < 0.05. RESULTS: The EcTI treatment in the ovalbumin-sensitized animals attenuated the maximal response of resistance and elastance of respiratory system after methacholine, the number of eosinophils, IL-4, IL-5, IL-13, IFN-y, NF-kB and iNOS-positive cells, isoprostane, elastic, collagen volume fraction, MMP-9, TIMP-1 and TGF-beta-positive cells compared to OVA group (p < 0.05). PCA was positive in sensitized animals. CONCLUSION: EcTI attenuates bronchial hyperresponsiveness, inflammation, remodeling and oxidative stress activation in this experimental asthma mice model. Although more studies are needed this inhibitor may be considered a future pharmacological tool for the treatment of asthma
172

Investigação da resposta imunológica antitumoral induzida por células B16F10 tratadas pela combinação p19Arf e interferon-beta em um modelo de vacinação profilático para melanoma murino / Investigation of the antitumor immune response induced by B16F10 cells treated with the p19Arf and Interferon-beta combination in a murine prophylatic model of melanoma vaccine

Ruan Felipe Vieira Medrano 25 April 2013 (has links)
Dados recentes do nosso laboratório demonstram que somente a co-transdução, não a tradução individual, com vetores adenovirais portadores de Interferon-beta (IFN?) (citocina imuno modulatória) e p19Arf (parceira funcional da proteína supressora de tumor p53) resulta na morte celular massiva do melanoma murino B16F10. A capacidade desse tratamento combinado de induzir uma resposta imune antitumoral ainda não foi avaliada. Dessa maneira, o objetivo do presente trabalho foi investigar se células B16F0 tratadas por essa combinação são capazes de induzir uma resposta imune antitumoral em um modelo de vacinação profilático de melanoma. Para isso, essas células foram co-transduzidas com os vetores AdPGp19 e AdPGIFN? e 48 horas depois, inoculadas como agente vacinal no flanco esquerdo (sítio da vacina) de camundongos C57BL/6 imunocompetentes. Sete dias após a última vacinação, esses animais foram desafiados com células B16F10 naïve no flanco direito (sítio do desafio). A progressão tumoral do desafio foi significativamente reduzida, mesmo quando o desafio tumoral foi feito 73 dias após da vacinação. Porém, como os animais imunizados desenvolveram tumores no sítio da vacina, condições para o uso dessas células tratadas foram avaliadas, revelando que: o número de células e de aplicações usadas durante a vacinação tem influência no aparecimento desse tumores, e que apenas com o tratamento combinado os camundongos permanecem livres de tumor. A influência do sistema imune para este resultado foi revelada após protocolo de imunussupressão. Em seguida, o papel da p19Arf e do IFN? na proteção antitumoral da combinação foi estudado. In vitro, os efeitos antitumorais da combinação parecem ser mais influentes da reposição de p19Arf do que da expressão de IFN?, mas já in vivo, na presença do sistema imune, foram mais dependentes do IFN?. Com a combinação estes efeitos mostraram-se mais pronunciados, induzindo uma proteção antitumoral e maior sobrevida aos animais vacinados. Estes resultados indicam que a combinação p19Arf e IFN? pode ser aplicada como um agente imunoterápico e sugerem que a associação entre morte celular e imuno estimulação pode beneficiar o tratamento contra o câncer / Previously, we have shown in a mouse melanoma model of in situ gene therapy that co-transduction, but not individual application, with adenovirus vectors expressing the Interferon-beta (IFN?) (immune modulatory cytokine) and p19Arf (functional partner of the p53 tumor suppressor) transgenes results in massive cell death and reduced tumor progression. However, the capability of this combined treatment to stimulate an antitumor immune response has not been evaluated. Therefore, the aim of this work was to investigate, trough a prophylactic vaccine model, if B16F10 cells treated by the p19Arf and IFN? combination could induce such immune response. To do so, these cells were co-transduced by the AdPGp19 e AdPGIFN? adenoviral vectors and 48 hours after, inoculated as a vaccine agent in the left flank (vaccine site) of immune competent C57BL/6 mice. Seven days after the last vaccine, a tumor challenge was done with naïve B16F10 cells in the right flank (challenge site). Tumor progression was markedly reduced, even when challenge was done 73 days after the vaccination. However, since these animals developed tumors where the vaccine was applied, more appropriate conditions for the use of these treated cells were pursued, thus revealing that: the number of cells and inoculations can dictate tumor development, and also, that only with the combined treatment was tumor formation abolished. The influence of the immune system for this result was revelead by performing an immune supression protocol. Next, the roles of p19Arf and of IFN? were studied. In vitro, the antitumor effects were stronger upon the introduction of p19Arf than IFN?, but in vivo, in the presence of the immune system, the effects were more IFN? dependent. In fact, these effects were more pronouced with the combined treatment, inducing protection against tumor formation and progression and increasing survival in the vaccinated animals. Taken together, these results demonstrate the application of cells treated by the p19Arf e IFN? combination as an effective vaccine agent and also indicates that the association between cell death and immune stimulation may benefit the treatment of cancer
173

Changes in the central nervous system after bilateral occlusion of the common carotid arteries in the hypertensive rats and the effect of Pien Tze Huang. / CUHK electronic theses & dissertations collection

January 2010 (has links)
Brain stroke is considered as one of the three diseases that threaten human health all over the world. Hypertension and cerebral arteriosclerosis are thought to be the most dangerous risk factors of brain stroke, and they frequently occur together, leading to ischemia of brain tissue. Unfortunately, it is not clear whether the pathological changes resulting from hypertension are related to those resulting from cerebral arteriosclerosis. There have been no ideal animal models mimicking the pathological changes in such a combined condition. In this thesis, an animal model of hypertension combined with cerebral arteriosclerosis in rats was established by occlusion of both the left and right common carotid arteries in spontaneous hypertension rats. Pien Tze Huang (PTH), a reputed traditional Chinese medicinal complex, contains Radix notoginseng, snake bile, calculus bovis, and musk and some other components that are known to protect vessels and cells from injuries. Since different tissue injuries share many common cellular mechanisms, the protection by PTH to in nerves and the circulation systems may also be benefical to cerebrovascular conditions as well. In present experiments, PTH was used to treat hypertension rats that also developed chronic brain ischemia as a result of the bilateral carotid occlusion, and its protective role for neurons and blood vessels was investiaged. / From the data above, more severe damage could be caused by hypertension combined with chronic ischemia. The model of SHR with bilaterally occluded common carotid artery can be used to study pathological changes resulted from hypertension combined with chronic ischemia. PTH was able to protect neurons in stroke. / In the initial part of the work, patients from clinics in two cities in South and North China were compared and analysed; they had been suffering from brain ischemic stroke. About two thirds of the stroke patients were found to have hypertension before the onset of stroke. Their prognosis was significantly worse than those stroke patients without hypertension. In the hypertensive rats with occluded arteries, mean of functional magnetic resonance imaging (fMRI) examination showed that brain blood flow was very weak or even transiently became undetectable at the beginning of the acute stage of brain ischemia, but was restored one hour after the occlusion surgery. In addition, pathological changes in brains of hypertensive rats with induced brain ischemia (carotid occlusion) were examined by Nissl staining, TUNEL staining, cell death ELISA and anti-oxidation enzymes. At day 15 after ischemia, a large number of pyramid cells in the hippocampus of SHR were lost and a great deal of apoptotic cells were found in the CA1 of the hippocampus, while activities of some enzyme including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) were increased. At day 30 and 60, some degenerative changes appeared to have subsided and the cells appeared morphologically normal. The activities of the above enzymes were also decreased at day 60. In WKY control rats with normal blood pressure, neurons in the CA1 were found less damaged after the bilateral carotid occlusion. It was found that apoptotic and dead cells were significantly reduced in rats with hypertension combined with chronic brain ischemia if they had been pre-treated with PTH. Moreover, brain stroke damage was less severe in this pretreated rats. / Zhang, Lihong. / "March 2010." / Adviser: WH Kwong. / Source: Dissertation Abstracts International, Volume: 72-01, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 116-134). / 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 Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
174

The role of norepinephrine in learning : cerebellar motor learning in rats

Paredes, Daniel A. January 2007 (has links)
Dissertation (Ph.D.)--University of South Florida, 2007. / Title from PDF of title page. Document formatted into pages; contains 144 pages. Includes vita. Includes bibliographical references.
175

Immunotherapy for autoimmune diabetes

Jain, Renu, Zaghouani, Habib. January 2008 (has links)
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed on April 1, 2010). Vita. Thesis advisor: Habib Zaghouani. "May 2008" Includes bibliographical references.
176

The Humanized Mouse Model: The Study of the Human Alloimmune Response: A Dissertation

King, Marie A. 22 May 2008 (has links)
The transplantation of allogeneic cells and tissues for the treatment of human disease has been a life-saving procedure for many thousands of patients worldwide. However, to date, neither solid organ transplantation nor bone marrow transplantation have reached their full clinical potential. Significant limitations to the advancement of clinical transplantation stem from our current inability to prevent the rejection of allogeneic tissues by the immune system of the host. Similarly, in patients that receive allogeneic bone marrow transplants, we cannot permanently prevent the engrafted immune system from mounting a response against the patient. This problem, termed graft versus host disease is the most prevalent cause of morbidity and mortality in recipients of allogeneic bone marrow transplants. Clinically, we rely on lifelong immunosuppression to prolong survival of allogeneic tissues within the host. Our currently available therapeutics burden patients with side-effects that range from being unpleasant to life-threatening, while in most cases offering only a temporary solution to the problem of alloimmunity. Efforts are underway to develop protocols and therapeutics that more effectively prevent the pathology associated with alloimmunity. To minimize patient risk, extensive pre-clinical studies in laboratory animals are conducted to predict clinical responses. In the case of immunologic studies, many of these pre-clinical studies are carried out in murine models. Unfortunately, studies of murine immunity often do not predict outcomes in the clinic. One approach to overcome this limitation is the development of a small animal model of the human immune system. In this dissertation, we hypothesized that NOD-scid IL2rγnull mice engrafted with human peripheral blood mononuclear cells (PBMC), termed the hu-PBMC-NOD-scid IL2rγnull model, would provide a model that more accurately reflects human immunity in vivo than other models currently available. To investigate this possibility, we first investigated whether NOD-scid IL2rγnull mice were able to support the engraftment of human PBMC. We found that NOD-scid IL2rγnull mice engraft with human PBMC at much higher levels then the previous gold standard model, the NOD-scid mouse. We then investigated the kinetics of human cell engraftment, determined the optimal cell dose, and defined the influence of injection route on engraftment levels. Even at low PBMC input, NOD-scid IL2rγnullmice reproducibly support high levels of human PBMC engraftment. In contrast to previous stocks of immunodeficient mice, we observed low intra- and interdonor variability of engraftment. We next hypothesized that the human PBMC engrafted in NOD-scid IL2rγnull mice were functional and would reject transplanted allogeneic human tissues. To test this, human islets were transplanted into the spleen of chemically diabetic NOD-scid IL2rγnull mice with or without intravenous injection of HLA-mismatched human PBMC. In the absence of allogeneic PBMC, the human islets were able to restore and maintain normoglycemia. In contrast, human islet grafts were completely rejected following injection of HLA-mismatched human PBMC as evidenced by return to hyperglycemia and loss of human C-peptide in the circulation. Thus, PBMC engrafted NOD-scid IL2rγnull mice are able to provide an in vivomodel of a functional human immune system and of human islet allograft rejection. The enhanced ability of NOD-scid IL2rγnull mice to support human cell engraftment gave rise to the possibility of creating a model of graft versus host disease mediated by a human immune system. To investigate this possibility, human PBMC were injected via the tail vein into lightly irradiated NOD-scid IL2rγnull mice. We found that in contrast to previous models of GVHD using human PBMC-injected immunodeficient mice, these mice consistently (100%) developed GVHD following injection of as few as 5x106PBMC, regardless of the PBMC donor used. We then tested the contribution of host MHC in the development of GVHD in this model. As in the human disease, the development of GVHD was highly dependent on host expression of MHC class I and class II molecules. To begin to evaluate the extent to which the PBMC-engrafted NOD-scid IL2rγnull humanized mouse model of GVHD represents the clinical disease, we tested the ability of a therapeutic in clinical trials to modulate GVHD in these mice. In agreement with the clinical experience, we found that interrupting the TNFα signaling cascade with etanercept delayed the onset and severity of disease in this model. In summary, we conclude that humanized NOD-scid IL2rγnull mice represent an important surrogate for investigating in vivo mechanisms of both human islet allograft rejection and graft versus host disease.
177

Poly(ADP)-Ribose Polymerase Activity in the Eukaryotic Mono-ADP-Ribosyl Transferase, ART2: a Dissertation

Morrison, Alan R. 03 September 2003 (has links)
The glycophosphatidylinositol(GPI)-linked membrane protein ART2 is an antigenic determinant for T lymphocytes that regulate the expression of diabetes in the BB/W rat model. Though little is understood of the physiologic role of ART2 on T lymphocytes, ART2 is a member of the mono-ADP-ribosyl transferase subgroup ofthe ADP-ribosyl transferase (ART) protein family. The ART protein family, which traditionally has been divided into mono-ADP-ribosyl transferases (mono-ARTs), poly(ADP)-ribose polymerases (PARPs), and ADP-ribosyl cyclases, influences various aspects of cellular physiology including: apoptosis, DNA damage repair, chromatin remodeling, telomere replication, cellular transport, immune regulation, neuronal function, and bacterial virulence. A structural alignment of ART2.2 with chicken PARP indicated the potential for ART2.2 to catalyze ADP-ribose polymers in an activity thought to be specific to the PARP subgroup and important for their regulation of nuclear processes. Kinetic studies determined that the auto-ADP-ribosyl transferase activity of ART2.2 is multitmeric and heterogeneous in nature. Hydroxylamine-cleaved ADP-ribose moieties from the ART2.2 multimers ran as polymers on a modified sequencing gel, and digestion of the polymers with snake-venom phosphodiesterase produced AMP and the poly(ADP)ribose-specific product, PR-AMP, which was resolved by analytical HPLC and structurally confirmed by ESI-MS. The ratio of AMP to PR-AMP was higher than that of PARP raising the possibility that the ART2.2 polymers had a different branching structure than those of PARP. This alternative branching was confirmed by the presence of ribose phosphate polymers in the snake venom phophodiesterase treated samples. The site of the auto-poly(ADP)-ribose modification was determined to be R185, a residue previously proposed to influence the level of auto-ADP ribosylation of ART2.2 by mutational analysis. These data provide the first demonstration of a hybrid between mono-ARTs and PARPs and are the earliest indication that PARP-like enzymes can exist outside the nucleus and on the cell surface.
178

Imunomodulação promovida pelo transplante de células tronco mesenquimais derivadas de medula óssea em lesões no sistema nervoso central / Immunomodulation promoted by bone marrow derived mesechymal stem cells transplanted in central nervous system injuries

Galindo, Layla Testa [UNIFESP] 22 February 2011 (has links) (PDF)
Made available in DSpace on 2015-07-22T20:50:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-22. Added 1 bitstream(s) on 2015-08-11T03:26:13Z : No. of bitstreams: 1 Publico-12887.pdf: 1856396 bytes, checksum: 42de9f60d780e16634f25ebf960a3c24 (MD5) / Lesões no sistema nervoso central (SNC) levam a permeabilidade da barreira hematoencefálica, o que permite a entrada de células do sistema imune e a ativação das células da glia, principalmente microglia e astrócitos. Esse processo desencadeia a secreção de mediadores inflamatórios por essas células. As citocinas são as principais moléculas da resposta neuroinflamatória e são críticas para a regulação desta resposta, exercendo uma variedade de ações no SNC. Células tronco mesenquimais (CTMs), que possuem potencial proliferativo e são capazes de originar linhagens celulares distintas e especializadas, também secretam essas moléculas, caracterizando um poder imunomodulador. As CTMs, particularmente as derivadas da medula óssea, promovem o reparo tecidual pela secreção de fatores que aumentam a regeneração do tecido, estimulando proliferação, migração e diferenciação de progenitores endógenos encontrados na maioria dos tecidos, diminuindo a resposta imune e inflamatória e a apoptose. A habilidade de essas células alterarem o microambiente através de sua influência trófica pode contribuir mais significativamente para o reparo do tecido que a transdiferenciação. Nossa hipótese é que as citocinas secretadas pelas CTMs poderiam participar da atração de células tronco neurais endógenas para um local de lesão no SNC, criando um microambiente favorável para essas células. Tendo isso em vista, esta tese teve como objetivo estudar os efeitos dos fatores secretados pelas CTMs sobre células tronco neurais (CTNs) in vitro, e analisar a expressão de citocinas por CTMs in vivo em um modelo de lesão traumática no SNC. Primeiramente, avaliamos os efeitos dos fatores secretados pelas CTMs sobre apoptose, proliferação e diferenciação de CTNs adultas derivadas da zona subventricular e cultivadas como neuroesferas. Para isso, cultivamos as neuroesferas em meio condicionado por CTMs derivadas de medula óssea. Além disso, foram realizadas lesões no córtex motor primário dos animais, seguidas da injeção de CTMs no local da lesão. Nossos resultados indicam que os fatores secretados pelas CTMs não induzem nem previnem a apoptose das CTNs, aumentam a proliferação dessas células e induzem maior expressão do gene GFAP in vitro, o que indicaria uma tendência a diferenciação em astrócitos. Nos experimentos in vivo, nossos resultados mostram que a injeção das CTMs em um modelo de lesão aguda no SNC diminui a expressão de citocinas pró-inflamatórias no tecido lesado, indicando que os fatores solúveis secretados por CTMs podem modular a inflamação no local lesado, o que pode ser interessante para a criação de um microambiente favorável para CTNs endógenas e conseqüentemente para o reparo do tecido lesado. / Central nervous system (CNS) injury breakes the impermeability of the blood brain barrier, this allows the invasion of immune cells and activation of glial cells, mainly microglia and astrocytes. This process triggers the secretion of inflammatory mediators by these cells. Cytokines are the main molecules in neuroinflammatory response and are critical for its regulation, exerting a variety of actions in the CNS. Furthermore, mesenchymal stem cells (MSC) which have proliferative potential and are able to originate different and specialized cell lineages, also secrete these molecules, characterizing its immunomodulatory function. MSC, particularly those derived from bone marrow, promote tissue repair by secreting factors that enhance tissue regeneration stimulating proliferation, migration and differentiation of endogenous stem-like progenitors found in most tissues, decreasing inflammatory and immune reactions and apoptosis. The ability of such cells to alter tissue microenvironment through its trophic influence may contribute more significantly than their capacity for transdifferentiation in effecting tissue repair.Our hypothesis is that MSC secreted cytokines could take part in the attraction of endogenous neural stem cells (NSC) to an injury site in the CNS, providing a favorable microenvironment for these cells. Our aim was to study the effects of factors secreted by MSC on NSC in vitro and to analyse the MSC cytokines expression in vivo in a model of CNS traumatic injury. We first evaluated the effects of MSC secreted factors on apoptosis, proliferation and differentiation of adult NSC derived from the subventricular zone and cultured as neurospheres. Neurospheres were cultured in MSC conditioned medium (MSC-CM), which was obtained from bone marrow-derived MSC cultures. Besides a traumatic injury was performed at the primary motor cortex of mice and MSCs were injected at the injury site. Our results show that MSC secreted factors do not induce or prevent NSC apoptosis, increase NSC proliferation and induce bigger expression of GFAP gene in vitro, this could indicate a tendency of differentiation to astrocytes. In vivo experiments show that MSC injection at an acute model of injury diminishes pro-inflamatory cytokines in the injured tissue, suggesting that MSC secreted factors may modulate the inflammation at the injury site, which may be interest to the development favorable microenvironment for endogenous NSC and consequently repair of the injured tissue. / TEDE / BV UNIFESP: Teses e dissertações
179

Identificação e análise estrutural e funcional de genes candidatos do cromossomo 4 de ratos SHR que possam influenciar a hipertensão essencial / Identification and structural and functional analysis of candidate genes on chromosome 4 in SHR that may influence essential hypertension

Samantha Kuwada Teixeira 10 December 2013 (has links)
O emprego de \"Total Genome Scan\" em modelos genéticos de doenças complexas tem sido fundamental para seleção de regiões cromossômicas envolvidas com traços complexos. Em nosso laboratório, identificamos cinco regiões cromossômicas associadas ao traço quantitativo pressão arterial (BP-QTL) que explicam 43% da variação da pressão arterial numa progênie obtida a partir de animais espontaneamente hipertensos (SHR) e \"Brown Norway\" (BN). Os BP-QTLs foram, então, validados por desenvolvimento de linhagens congênicas, incluindo uma para o cromossomo 4 (SHR.BN4) cuja substituição das sequências SHR pelo do animal BN levou a redução da pressão arterial sistólica basal (~14 mm Hg). O objetivo deste trabalho foi identificar as variantes genéticas candidatas neste intervalo cromossômico com base em diferenças no padrão de expressão gênica e na presença de alterações genéticas não sinônimas \"missense\" ou em regiões regulatórias conservadas que possam estar envolvidas na gênese da hipertensão. Identificamos 533 genes com expressão renal, dentre os 682 do intervalo, sendo que 28 apresentaram padrão de expressão diferente entre amostras de animais adultos (congênico vs. SHR) e seis apresentaram alterações não sinônimas \"missense\". É importante salientar que dos genes diferentemente expressos, encontramos alterações estruturais em regiões conservadas com potencial de participar na regulação em 11. Em conjunto, utilizamos uma plataforma integrada para selecionar 34 genes candidatos no cromossomo 4, dos quais 17 genes serão priorizados, para ser investigados quanto sua contribuição na hipertensão arterial do SHR e na hipertensão primária humana / Total genome scan in genetic models of complex diseases have been instrumental to select candidate genes underlying complex traits. We previously mapped 5 blood pressure related quantitative trait loci (BP-QTLs) that explain about 43% of the BP variance in a progeny derived from Spontaneous Hypertensive Rat (SHR) and Brown Norway (BN) rats. The BP-QTLs were then validated by derivation of congenic strains, including one for chromosome 4 (SHR.BN4) in which a segment from BN replaced the SHR sequences reducing basal systolic BP (~14 mm Hg). The aim of this project is to identify the candidate genetic variants within the chromosome interval based on differences in renal gene expression patterns and structural changes in both non-synonymous missense or within adjacent regulatory sequences that may contribute to hypertension. We identified 533 genes with renal expression, out of 682 in the interval, in which 28 presented differences in expression pattern in adult samples (congenic vs. SHR) and six presented non-synonymous missense alterations. In addition, 11 out of 28 differentially expressed genes showed structural alterations in adjacent conserved regions that potentially contribute to gene regulation. Taken together, using the proposed combination of strategies, we selected 34 hypertensive candidate genes in chromosome 4, in which 17 will be prioritized, to be further explored to assess their contribution to hypertension in the SHR and to essential hypertension in humans
180

Estudo de resistência à murcha-de-fusarium e identificação de QTLs em feijeiro-comum / Study of fusarium wilt resistance and identification of QTLs in common bean

Valdo, Stella Cristina Dias 27 April 2017 (has links)
Submitted by Onia Arantes Albuquerque (onia.ufg@gmail.com) on 2018-10-08T13:49:50Z No. of bitstreams: 2 Tese - Stella Cristina Dias Valdo - 2017.pdf: 4757114 bytes, checksum: 62d9148c9c6315952ac5a86bdb1f9417 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Rejected by Luciana Ferreira (lucgeral@gmail.com), reason: Olhe o espaço a mais na citação: VALDO, S. C. D. Estudo de resistência à murcha-de-fusarium e identificação de QTLs em feijeiro-comum. 2017. 178 f. Tese (ESPAÇO A MAIS Doutorado em Genética e Melhoramento de Plantas) - Universidade Federal de Goiás, Goiânia, 2017. on 2018-10-09T10:59:43Z (GMT) / Submitted by Onia Arantes Albuquerque (onia.ufg@gmail.com) on 2018-10-09T11:17:13Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese - Stella Cristina Dias Valdo - 2017.pdf: 4757114 bytes, checksum: 62d9148c9c6315952ac5a86bdb1f9417 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-10-09T11:41:12Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese - Stella Cristina Dias Valdo - 2017.pdf: 4757114 bytes, checksum: 62d9148c9c6315952ac5a86bdb1f9417 (MD5) / Made available in DSpace on 2018-10-09T11:41:12Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Tese - Stella Cristina Dias Valdo - 2017.pdf: 4757114 bytes, checksum: 62d9148c9c6315952ac5a86bdb1f9417 (MD5) Previous issue date: 2017-04-27 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / The common bean (Phaseolus vulgaris) crop plays an important role in the culture and economy of Brazil. It is cultivated in all Brazilian regions and is affected by several diseases like fusarium wilt which is caused by Fusarium oxysporum f. sp. phaseoli (soil-born fungus). This disease brings significant losses in common bean culture and genetic resistance is the primary form of control. One of the core goals of breeding programs is the development of resistant cultivars, therefore the objectives of this work are: i) To select F. oxysporum f. sp. phaseoli resistant F5:7 lines resulted from the crossing between Ouro Branco X CNFP10132, under controlled field and environment conditions ii) To identify SSR markers and QTL-linked SNPs associated with the resistance of common bean to fusarium wilt using 92 recombinat inbred lines(RILs) resulted from the crossing between Ouro Branco x CNFP10132. In the first study, 140 lines, the breeders Ouro Branco and CNFP10132, BRS Esplendor (resistant) and BRS Supremo (susceptible) as controls were evaluated. Field trials were conducted in a center pivot area where natural infestation of the pathogen occurs. The treatments were evaluated in summer and winter crop and the experimental design used was 12x12 triple lattice. The two controlled environment trials were conducted in a completely randomized design. The treatments were inoculated by cutting and immersing the roots in a conidial suspension, which was adjusted to 1x106 conidia/ml for five minutes. The evaluation was performed using a scale of nine grades that represent the severity of the disease: 1 – absence of symptoms and 9 – over 75% of foliage with wilt symptoms. Data were submitted to analysis of variance and Scott-Knott test for both environments. The area under the disease progress curve (AUDPC) and genetic parameters were estimated for controlled environment tests. Significant differences were observed for crops and for controlled environment trials, indicating that environment influences directly the severity of the disease. Highly significant differences were found for lines in all environments evaluated, demonstrating the existence of genetic variability, which allows the selection of resistant lines resistant to fusarium wilt. Treatments were classified in different groups according to the Scott-knott test. When considering the lowest averages in field, controlled environment and AUDPC, the strains Ouro Branco x CNFP 10132.140, Ouro Branco x CNFP 10132.49, Ouro Branco x CNFP 10132.12, Ouro Branco x CNFP 10132.90 and Ouro Branco x CNFP 10132.48 were prominent and are candidates to produce a breeding program. Heritability estimates were high for all environments, mean of 85.48% for field and 95.47% for controlled environment. Therefore, selection for resistance to F. oxysporum f. sp. phaseoli of these lines, will be successful. In the second study it was extracted DNA from 92 lines and from genitors for genotyping with SSRs and SNPs. In order to obtain the localization of these markers, sequences of the primers were aligned to the andean genome of the common bean. The method of single marker (analysis of QTLs based on linear regression) was used to identify QTLs associated with fusarium wilt resistance. These markers were considered significant when brought up p-value <0.05. Ninety-three markers were linked to 104 QTLs associated with fusarium wilt resistance and among these, were considered significant in more than one environment PV 115, PV 251, BARC-PV-0004089, BARC-PV-0004548, BARC-PV-0003450, BARC-PV-0006051, BARC-PV-0003368 , BARC-PV-0005477 and BARC-PV-0004897. However only the BARC-PV-0003450 marker was highly significant in the two environment controled trials (p <0.001) and winter crop (p <0.01) and explained up to 21.5% of the phenotypic variance. Subsequently, the gene annotation was made considering the location of all markers that were significant at p <0.01 comprising 500 kb before and after the localization. 960 coded transcripts were annotated. It was observed in gene annotation that BARC-PV-0003450 marker is located on the chromosome 8, 338.54 kb distant of the gene Phvul.008G014700 which is associated with the putative protein RPP13 related to disease resistance, identified in Arabidopsis thaliana. This protein belongs to the third class of resistance genes that encloses the domain called Leucine-Rich Repeats (LRR). This domain is involved in the recognition of the pathogen by the host during the infection process. Therefore, this marker is suitable for marker- assisted selection aiming the development of cultivars resistant to fusarium wilt. / A cultura do feijoeiro-comum (Phaseolus vulgaris) tem importância cultural e econômica no Brasil. O feijoeiro-comum é cultivado em todas as regiões brasileiras e é acometido por várias doenças, como a murcha-de-fusarium, causada pelo fungo habitante de solo Fusarium oxysporum f. sp. phaseoli. Esta doença causa significativas perdas na cultura e a principal forma de controle é a resistência genética. Desenvolver cultivares resistentes é um dos alvos dos programas de melhoramento, portanto os objetivos deste trabalho foram: i) selecionar linhagens resistentes obtidas de população F5:7 oriunda do cruzamento entre Ouro Branco e CNFP10132 para F. oxysporum f. sp. phaseoli, em condições de campo e de ambiente controlado e ii) identificar marcadores SSR e SNP's ligados a QTLs associados à resistência do feijoeiro-comum à murcha-de-fusarium utilizando 92 linhagens recombinantes endogâmicas (RILs) derivadas do cruzamento Ouro Branco x CNFP10132. No primeiro estudo 140 linhagens, os genitores Ouro Branco e CNFP10132, duas testemunhas BRS Esplendor (resistente) e BRS Supremo (suscetível) foram avaliados. Os ensaios de campo foram conduzidos em área de pivô central onde ocorre infestação natural do patógeno. Os tratamentos foram avaliados em duas safras (safra das águas e de inverno) em delineamento de látice triplo 12x12. Os dois ensaios em ambiente controlado foram conduzidos em delineamento inteiramente causalizado. As plantas foram inoculadas utilizando o método de corte de raiz e imersão destas na suspensão de conídios, que foi ajustada para 1x106 conídeos/mL durante cinco minutos. A avaliação foi feita utilizando uma escala de notas de nove graus que representam a severidade da doença: sendo 1 - ausência de sintomas e 9 - acima 75% da folhagem com sintomas de murcha. Os dados foram submetidos à análise de variância e teste de Scott-Knott para os ambos ambientes. Para os ensaios em ambiente controlado foram estimados área abaixo da curva do progresso da doença (AACPD) e parâmetros genéticos. Foram observadas diferenças significativas para safras e para ensaios de ambiente controlado, indicativo de que o ambiente influencia diretamente na severidade da doença. Foram encontradas diferenças altamente significativas para linhagens em todos os ambientes avaliados, evidenciando a existência de variabilidade genética, o que possibilita seleção de linhagens resistentes à murcha-de-fusarium. Ao considerar as menores médias em campo, ambiente controlado e ACCPD as linhagens Ouro Branco x CNFP 10132.140, Ouro Branco x CNFP 10132.49, Ouro Branco x CNFP 10132.12, Ouro Branco x CNFP 10132.90 e Ouro Branco x CNFP 10132.48 se destacaram e são candidatas para compor o programa de melhoramento. As estimativas de herdabilidade foram altas para todos os ambientes, média de 85,48% para campo e 95,47% para ambiente controlado. Portanto, a seleção para resistência à F. oxysporum f. sp. phaseoli dentre estas linhagens, será bem sucedida. No segundo estudo foi extraído o DNA de 92 linhagens e dos genitores para genotipagem com marcadores SSRs e SNPs. Para obtenção da localização destes marcadores as sequências dos primers foram alinhadas no genoma andino do feijoeiro-comum. O método de mapeamento por marcas simples (análise de QTLs por meio da regressão linear) foi utilizado para identificar QTLs associados à resistência à murcha-de-fusarium. Foram considerados marcadores significativos os que apresentaram p-valor<0,05. Noventa e três marcadores foram identificados ligados a 104 QTLs associados à resistência à murcha-de-fusarium. Dentre estes marcadores destaca-se os que foram significativos em mais de um ambiente PV 115, PV 251, BARC-PV-0004089, BARC-PV-0004548, BARC-PV-0003450, BARC-PV-0006051, BARC-PV-0003368, BARC-PV-0005477 e BARC-PV-0004897. Dentre os marcadores, somente o marcador BARC-PV-0003450 foi altamente significativo nos dois ensaios, em ambiente controlado (p<0,001) e na safra de inverno (p<0,01), e explicou até 21,5% da variância fenotípica. Foi feita a anotação gênica considerando a localização de todos os marcadores que foram significativos à p<0,01 e abrangeu 500 kb anterior e posterior à localização. Foram anotados 960 transcritos codificados. Ainda observou-se que o marcador BARC-PV-0003450 está localizado no cromossomo 8 distante 338,54 kb do gene Phvul.008G014700 o qual está associado à proteína putativa RPP13 relacionada com resistência à doenças, identificada em Arabidopsis thaliana. Esta proteína pertence à terceira classe de genes de resistência que engloba o domínio denominado de Repetições Ricas em Leucina (LRR; Leucine Rich Repeats). Este domínio está envolvido no reconhecimento do patógeno pelo hospedeiro durante o processo de infecção. Portanto há a possibilidade de selecionar linhagens resistentes à murcha-de-fusarium e identificar QTLs que possivelmente estão ligados aos marcadores utilizados

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