• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 10
  • 5
  • 1
  • 1
  • 1
  • Tagged with
  • 23
  • 23
  • 8
  • 7
  • 6
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 3
  • 3
  • 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.
1

Computer controlled device to independently control flow waveform parameters during organ culture and biomechanical testing of mouse carotid arteries.

Gazes, Seth Brian. January 2009 (has links)
Thesis (M. S.)--Mechanical Engineering, Georgia Institute of Technology, 2010. / Committee Chair: Rudy Gleason; Committee Member: Raymond Vito; Committee Member: W. Robert Taylor. Part of the SMARTech Electronic Thesis and Dissertation Collection.
2

Control of cellular plasticity during tissue remodeling in C. elegans

Aghayeva, Ulkar January 2019 (has links)
Dauer larva formation in C. elegans is a life-history polyphenism that relies on the function of several pathways, including insulin, TGFβ and nuclear hormone receptor signaling. The downstream effectors of these pathways, DAF-16/FOXO, DAF-3/Co-Smad and DAF-12/VDR, are transcription factors (DAF TFs) with broad or ubiquitous expression patterns, null mutations in which result in the inability to form dauers regardless of environmental conditions. In preparation for the dauer diapause, all tissues of the worm undergo extensive morphological and functional remodeling in a coordinated manner. The broad goal of my thesis is to understand how these transcription factors act in different tissues of the worm to regulate the dauer-specific tissue remodeling and gene expression changes. In addition to characterizing dynamic expression pattern of chemosensory GPCR genes in dauer, which revealed an additional layer of plasticity and provided novel entry points to studying remodeling in distinct neuron classes and non- neuronal tissues, I have developed molecular tools – conditional alleles of the daf TFs – that allowed me to address the question of tissue-specificity and cell-autonomy of the DAF TFs in a previously inapproachable way. I have found that DAF TFs act in both cell-autonomous (DAF-16 in neurons, intestine, pharynx) and non-autonomous manner (DAF-16 in the pharynx) to control dauer tissue remodeling. Unlike DAF-16 and DAF-12, the function of DAF-3 in the dauer decision appears to be largely determined by its action in neurons, and specifically in sensory neurons. The three TFs also differ in their roles in pharynx remodeling: while DAF-16 controls dauer pharyngeal morphology and activity both cell-autonomously and non- autonomously, DAF-12 or DAF-3 depletion from pharyngeal muscle does not affect the dauer pharyngeal phenotypes. Yet, all three TFs are required continuously throughout all tissues to maintain the dauer state, once the decision to enter dauer has been made. This work is a first attempt to characterize tissue-specific roles of all transcriptional effectors of the dauer pathways in a systematic way, and contributes to a fundamental understanding of a polyphenic developmental switch regulated by highly conserved molecular pathways.
3

Development of a novel organ culture system allowing independent control of local mechanical variables and its implementation in studying the effects of axial stress on arterial remodeling

Dominguez, Zachary. January 2008 (has links)
Thesis (M. S.)--Mechanical Engineering, Georgia Institute of Technology, 2009. / Committee Chair: Vito, Raymond; Committee Member: Gleason, Rudolph; Committee Member: Rachev, Alexander. Part of the SMARTech Electronic Thesis and Dissertation Collection.
4

Caracterização clínico-patológica e imuno-histoquímica de componentes celulares e da matriz conjuntiva extracelular de mucoceles da boca

Conceição, Jamile Gomes January 2012 (has links)
Submitted by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2013-04-18T18:23:28Z No. of bitstreams: 1 Jamile Gomes Conceição Caracterizaçao clinico...pdf: 1293623 bytes, checksum: 81e290f73ff54554a4e039099727ca5b (MD5) / Made available in DSpace on 2013-04-18T18:23:28Z (GMT). No. of bitstreams: 1 Jamile Gomes Conceição Caracterizaçao clinico...pdf: 1293623 bytes, checksum: 81e290f73ff54554a4e039099727ca5b (MD5) Previous issue date: 2012 / Universidade Federal da Bahia. Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz / Mucoceles são lesões comuns da cavidade oral, causadas por alterações nos ductos excretórios de glândulas salivares menores. A fim de contribuir para um melhor conhecimento do perfil biológico destas lesões, este trabalho teve como objetivo estudar os aspectos clínico-patológicos em uma amostra de mucoceles da boca, bem como componentes celulares como vasos sanguíneos (anti-CD34), mastócitos (triptase de célula mastocitária), macrófagos (anti-CD68) e da matriz extracelular (metaloproteinase de matriz -1 e -9), por meio da técnica imuno-histoquímica. Foram estudados 100 casos de mucocele de extravasamento, o seu conteúdo de fibrose (picrossirius) e 32 casos investigados para as proteínas propostas, adotando-se critérios morfométricos e semiquantitativos. As lesões de mucocele atingiram mais o lábio inferior e a segunda e terceira décadas de vida, com média de 23.2 anos de idade (DP±12,24), sendo os homens mais acometidos pela lesão (56%). O tamanho médio foi de 1,1 cm (DP±0,57). Os vasos sanguíneos CD34 positivos estavam presentes em todos os espécimes (média de 55 microvasos por mm2; DP±0,36), mas a medida que se aproximavam do lúmen cístico pareciam desaparecer. Os mastócitos estavam presentes em todos os casos (média= 7.4; DP±0,12), mais concentrados na região cápsula em torno do tecido de granulação, reduzindo-se neste último. Os macrófagos estavam presentes no tecido de granulação (média= 88; DP±0,52), também em todos os casos, mas especialmente concentrados na superfície luminal e dentro da cavidade cística, sugerindo um importante papel na fagocitose de muco. MMPs apresentaram marcação variável presentes em fibroblastos, células inflamatórias e matriz extracelular, sendo MMP-1 ausente em um caso e a MMP-9 em dois. A fibrose também mostrou-se variável entre os casos. Apesar de existir associação estatística ente macrófagos e MMP1 (p<0.05, Kruskal Wallis), diferença significativa entre os diferentes marcadores não foi encontrada (p> 0.05, Kruskal Wallis). Este estudo contribuiu para o conhecimento dos mucoceles da boca em uma amostra representativa da população da Bahia, destacando que a dinâmica de desenvolvimento de formação dessas lesões envolve migração e interação chaves entre componentes celulares e da matriz extracelular importantes para o remodelamento tecidual dos mucoceles. / Mucoceles are common lesions of the oral cavity, caused by damage to the excretory ducts of salivary glands. The present study investigated a sample of oral mucoceles in our population, to describe their clinical and histopathological features, and to assess cell components such as blood vessels, mast cells, macrophages, and matrix metalloproteinases (MMPs – 1 and -9), using immunohistochemistry, for a better understanding of biological profile of this lesion. Histochemistry using Picrossirius red staining was also included. The sample consisted of 100 oral mucoceles, 32 of which were included for investigating both cell components and MMPs, adopting morphometrical and semi-quantitative criteria. The lesions were located most often on the lower lip and second and third decades of life, with a mean of 23.2 years (SD±12,24). Males had a higher frequency (56%) and mean size of the lesions was 1.1cm ((DP±0,57). CD34-positive blood vessels were present in all specimens (mean, 55 microvessels per mm2), but as they approached the cystic lumen seemed to disappear. Mast cells were present in all cases (mean= 7.4; SD±0,12) and concentrated in the capsule surrounding the granulation tissue, although they were reduced in the latter. The macrophages were present in the granulation tissue (mean=88; SD±0.52), also in all cases, but they were especially concentrated on the luminal surface and within the cystic cavity, indicating a pivotal role in phagocytosis of mucus. MMPs showed variable immunostaining and were found in fibroblast and inflammatory cells, however, they were absent in one case of MMP1 and two cases of MMP9. Fibrosis was also variable in all of specimens. Although there was a statistical association between macrophages and MMP1 (P<0.05, Kruskal Wallis), significant difference between the different markers was not found (P<0.05, Kruskal Wallis). This study provides an important insight to the knowledge of oral mucoceles from a sample from Salvador, Bahia, Brazil. Furthermore, it highlights that the development dynamic of these lesions involves migration and interaction of key cellular and extracellular matrix components which are essential to the tissue remodeling of oral mucoceles.
5

MT1-MMP, MMP-2, MMP-9, TIMP-1,-2,-3 e a proliferação celular da região odontogenica de dentes incisivos de ratos adultos = efeito da doxiciclina em condição acelerada de proliferação celular / MT1-MMP, MMP-2, MMP-9, TIMP-1,-2,-3 and the cell proliferation in the odontogenic region of the incisor tooth of adult rats : effects of doxycycline in the accelerated cell proliferation condition

Gomes, Jose Rosa 15 August 2018 (has links)
Orientador: Pedro Duarte Novaes / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-15T05:31:53Z (GMT). No. of bitstreams: 1 Gomes_JoseRosa_D.pdf: 2733880 bytes, checksum: d4bbbffbb909027da9301acc0ba19e95 (MD5) Previous issue date: 2010 / Resumo: Metaloproteinases (MMPs) são enzimas que degradam os componentes da matriz extracelular e são reguladas por moléculas denominadas inibidores teciduais de metaloproteinases (TIMPs). São poucos os relatos da função dessas moléculas nos tecidos que sustentam, constituem e dão origem aos dentes. Entretanto, já foi mostrado que antibióticos como a doxiciclina podem reduzir a atividade dessas enzimas. Considerando que o incisivo de rato apresenta crescimento e erupção continuados ao longo da vida do animal assegurada por constante proliferação e diferenciação das células localizadas na região apical (odontogênica) em esmalte, dentina e ligamento periodontal, este se torna um excelente modelo para o estudo da atividade de MMPs e seus inibidores sobre o processo proliferativo e eruptivo do mesmo. Assim, os objetivos deste estudo foram: 1-Avaliar, na região odontogênica, o efeito da doxiciclina e da hipofunção sobre a expressão e a atividade da MMP-2 e MMP-9; a expressão dos TIMP-1,-2,-3 por meio das técnicas de zimografia, zimografia reversa, imunohistoquimica e a expressão de MT1-MMP pela técnica de Western Blot, 2- Avaliar o efeito da doxiciclina e a condição hipofuncional sobre a taxa de erupção dos dentes incisivos, 3- Avaliar a proliferação celular da região odontogênica, na presença de doxiciclina e hipofunção, por meio de marcador de proliferação celular, 4- Estabelecer relação entre os efeitos da doxiciclina, a expressão das MMPs, TIMPs, a proliferação celular da região odontogênica e o processo de erupção. Foram usados de 5 a 7 ratos machos adultos divididos em 4 grupos: controles - normofuncional (NF) e doxinormofuncional (DNF) e tratados - hipofuncional (HP) e doxhipofuncionais (DHP). Os grupos HP e DHP tiveram os dentes esquerdos inferiores cortados com broca de alta rotação e medidos a cada dois dias durante 12 dias. Nos dentes dos grupos NF e DNF uma marca foi feita para estimar a taxa de erupção realizada da margem gengival até a marca ou até o final do dente nos grupos HP e DHP. Os grupos DNF e DHP receberam dose diária matutina, de 80mg/kg de doxiciclina diluída em água por agulha de gavagem durante 14 dias. Os ratos foram sacrificados por deslocamento cervical e as hemimandibulas foram processadas para os métodos de imunohistoquimica, zimografia e Western Blot. Os resultados mostraram que os tratamentos não alteraram a atividade e expressão de MMP-2 e MMP-9 e nem de TIMP-1 e TIMP-3. Entretanto, a hipofunção aumentou a taxa de erupção, a expressão de MT1-MMP, TIMP-2 e a proliferação celular quando comparadas com os grupos controles. Conclui-se que: 1- MMP-9 não participa da remodelação da matriz extracelular na região odontogênica, 2- A doxiciclina não altera a erupção, atividade e expressão das moléculas avaliadas e nem a proliferação celular; 3- A condição hipofuncional altera; aumentando a erupção, a expressão de MT1-MMP, TIMP-2 e a proliferação celular, 4- Existe relação entre o aumento da erupção e proliferação celular bem como entre a expressão de MT1-MMP/TIMP-2 e a proliferação celular sugerindo papel importante dessas moléculas nos processos de proliferação e erupção / Abstract: Metalloproteinases (MMPs) are enzymes that degrade extracellular matrix components and are regulated by molecules called tissue inhibitors of metalloproteinases (TIMPs) and there is few reports of the function of these molecules in the tissues that support and give rise to teeth. However, it has been shown that antibiotics such as doxycycline can reduce the activity of these enzymes. Whereas the rat incisor has erupted and continued growth over the life of the animal provided by continuing proliferation and differentiation of cells in the apical region (odontogenic) on enamel, dentin and periodontal ligament, it becomes an excellent model for studying the activity of MMPs and their inhibitors on the proliferative and eruption process. Thus the aims of this study were: 1-To study in odontogenic region, the effects of doxycycline and hypofunctional condition on the expression and activity of MMP-2 and MMP-9, the expression of TIMP-1, -2, -3, using techniques of zymography, reverse zymography, immunohistochemstry and the expression of MT1-MMP by Western Blot; 2 - To evaluate the effect of doxycycline and hypofunctional condition on the eruption rate of incisors. 3 - To estimate the cellular proliferation of odontogenic region in the presence of doxycycline and hypofunctional eruption condition, using cell proliferation marker, 4 - Establish relationship between the effects of doxycycline, the expression of MMPs, TIMPs, the cellular proliferation of the odontogenic region and the process of eruption. Were used 5 to 7 adult male rats divided into 4 groups: control-functioned normally (NF) and doxinormofuncional (DNF) and treated-hipofuncional (HP) and doxihipofuncional (DHP). The groups HP and DHP had left lower teeth cut with high-speed drill every two days until for 12 days. In the teeth of groups NF and DNF a mark was made to estimate the rate of eruption of the gingival margin held up to the mark or until the end of the tooth in groups HP and DHP. Groups DNF and DHP received daily morning dose of 80mg/kg of doxycycline diluted in water by needle gavage for 14 days. The rats were sacrificed by cervical dislocation, and the hemimandibles were processed for immunohistochemical methods, zymography and Western Blot. The results showed that the treatments did not alter the activity and expression of MMP- 2 and MMP-9 nor TIMP-1 and TIMP-3. However, the hypofunction increased the rate of eruption, the expression of MT1-MMP, TIMP-2 and cell proliferation when compared with control groups. We conclude that: 1 - MMP-9 does not participate in remodeling the extracellular matrix in the odontogenic region 2 - Doxycycline does not alter the eruption, activity and expression of the molecules assessed and not cell proliferation, 3 - The condition hipofuncional changes, increasing the eruption, the expression of MT1-MMP, TIMP-2 and cell proliferation, 4 - There is a relationship between the eruption and increased cell proliferation and between the expression of MT1-MMP/TIMP-2 and cell proliferation suggesting an important role of molecules in the cell proliferation and eruption processes / Doutorado / Histologia e Embriologia / Doutor em Biologia Buco-Dental
6

Characterizing the structure-function relationships of the mouse cervix in pregnancy: Towards the development of a hormone-mediated material model for cervical remodeling.

Yoshida, Kyoko January 2016 (has links)
The timely remodeling of the cervix from a mechanical barrier into a soft, compliant structure, which dilates in response to uterine contractions is crucial for the safe delivery for a term baby. A cervix which softens too early in the pregnancy is implicated in spontaneous preterm births (sPTB). Currently, 15 million babies are affected by PTB annually, early diagnosis is difficult, and 95% of all PTBs are unmanageable by available therapies. These statistics highlight the need to better understand the biological processes involved in cervical remodeling and its downstream effects on material properties. To address this need, we propose the development of a hormone-mediated material constitutive model for the cervix where steroid hormone actions on key tissue constituents are incorporated into a microstructure-inspired material model. As the first steps towards the development of this model, the main objective of this dissertation work is to understand the key structure-mechanical function relationships involved in pregnancy. To understand cervical material property changes, the equilibrium swelling and tensile response of the nonpregnant and pregnant mouse cervix is measured, a porous fiber composite material model is proposed, and the model is fit to the mechanical data then validated. To better understand key tissue constituents involved, the evolution of intermolecular collagen crosslinks is determined in normal pregnancy and the role of the small proteoglycan, decorin, and elastic fiber structure on cervical mechanical function is investigated. The results presented here demonstrate that a porous, continuously distributed fiber composite model captures the three-dimensional mechanical properties of the nonpregnant and pregnant cervix. The material property changes of the cervix in a 19-day mouse gestation is described as a four order of magnitude decrease in the parameter associated with the fiber stiffness. We provide quantitative evidence to demonstrate the role of collagen crosslinks on tissue softening in the first 15 days, but not in the latter stages of a mouse pregnancy. A role of elastic fiber structure on cervical mechanical function is demonstrated, as well as distinct roles of estrogen on elastic fiber structure and progesterone on collagen fibril structure. Lastly, an analysis of the time-dependent response of cervices from nonpregnant, normal pregnant, and induced PTB mice are presented. This dissertation concludes by reviewing the presented data within the context of the proposed framework to suggest future directions towards its development.
7

Development of a novel organ culture system allowing independent control of local mechanical variables and its implementation in studying the effects of axial stress on arterial remodeling

Dominguez, Zachary 25 August 2008 (has links)
Arterial remodeling is a process by which arteries respond to sustained changes in their mechanical environment. This process occurs in a way such that an artery's local mechanical environment (circumferential, shear, and axial stress) is maintained at a homeostatic level. However, most studies utilize a methodology that controls the global parameters (pressure, flow rate, and axial stretch). This approach often confounds the results since the actual drivers of remodeling are not independently isolated. This research involved developing a methodology and system capable of independently controlling each of the local parameters and examining the effect of axial stress on remodeling. An organ culture system capable of monitoring and controlling the three global parameters and calculating the cross sectional geometry was developed. This combination of hardware was incorporated into LabVIEW which afforded the user the ability to define desired values for the local mechanical parameters. Porcine common carotid arteries were cultured for seven days in this system under physiologically normal circumferential and shear stresses and a constant axial stress of either 150 kPa or 300 kPa. Material response, general arterial morphology, tissue viability, and collagen synthesis were examined in order to gauge the effectiveness of the organ culture system and assess any arterial remodeling. The results of this study demonstrate the ability of the organ culture system in achieving and maintaining target values of stress throughout the culture period. Cell viability, general arterial morphology, and collagen synthesis rates were maintained for all arteries. The elevated axial stress appeared to cause a softening of the artery in both the axial and circumferential direction. It was hypothesized that this softening was the result of a changing collagen structure. Additional softening seen in arteries was attributed to the effects of the culture system.
8

Detecção de metaloproteinases da familia das gelatinases e de seus inibidores no ligamento interpubico do camundongo, durante a prenhez / Detection of metalloproteinases of the gelatinases family and their inhibitors in the interpubic ligament of the mouse, during pregnancy

Rosa, Renata Giardini 02 December 2007 (has links)
Orientador: Paulo Pinto Joazeiro / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-08T07:41:05Z (GMT). No. of bitstreams: 1 Rosa_RenataGiardini_M.pdf: 17497902 bytes, checksum: 703ffbe86316dbd66437c0d105646fed (MD5) Previous issue date: 2007 / Resumo: Durante a prenhez de alguns roedores ocorre um acentuado processo de remodelação da sínfise púbica (SP). No camundongo, esta articulação fibrocartilaginosa é gradativamente formada por um tecido conjuntivo fibroso, resultando no ligamento interpúbico (LI) entre os coxins de cartlagem na etapa final da prenhez. Logo após o parto, este ligamento é rapidamenteremodelado e o espaço entre os ossos púbicos se fecha por volta do quinto dia pós-parto. Sabe-se que o hormônio relaxina facilita o crescimento e remodelação dos órgãos do trato reprodutor feminino, alterando a regulação dos processos bioquímicos envolvidos na remodelação da matriz extracelular (MEC) do útero gravídico e da cérvice. Porém pouco se conhece sobre a sínfise em relação ao envolvimento de metaloproteinases (MMPs) nessa remodelação. Assim como, da participação de células inflamatórias, que poderiam estar envolvidas no processo de remodelaçãoda sínfise púbica do camundongodurantea prenhez. Neste estudo, foram utilizadas sínfises de camundongos virgens e ligamento interpúbico de animais prenhes para a detecção de MMPsin vivo e in vitro (explante de 24 horas). As MMPs da família das gelatinases (MMP-2 e MMP-9) foram caracterizadas pela zimografia e por meio de ensaios imunohistoquímicos,assim como a MMP-8 (colagenase2) associada,quase que exclusivamente, com o processo inflamatório. Também foram utilizadas microscopia eletrônica de transmissão e microspia de luz associada às colorações seletivas para evidenciar os tipos celulares que poderiam estar participandodo processo de remodelaçãoda sínfise púbica. A zimografia demonstrou a presença das gelatinases MMP-2 e MMP-9, ambas como pré e pró-enzimas, na SP e no LI. Imunohistoquímicadetectou a reação positivade gelatinasese também de MMP-8em células seme~hantesaos fibroblastos. A caracterização morfológica evidenciou que as células semelhantesa fibroblastos na sínfise de animais virgens estão próximasa matriz pericelular, ao passo que durante a prenhez, há um aumento deste subcompartimento, entre célula e matriz. As análises qualitativas e quantitativas, mostramum reduzido númerode granulócitosna sínfise de animaisvirgens e no ligamento intepúbico durante a prenhez. Dados obtidos neste trabalho suportam a hipótese de que as gelatinases estão envolvidas na remodelação da sínfise por processos intrínsecos, evidenciando que tanto as modificaçõesdo fenótipo de células semelhantes a fibroblastos, como as modificaçõesquímicas da MEC, são fundamentais para o rearranjo desta articulação durante a prenhez, parto e pós-parto no camundongo. A extensão da remodelação da MEC sugere o papel dos hormônios da prenhez na modulação da interação célula-matriz independentemente de uma reação do tipo inflamatória descrita em outros órgãos durante a prenhez / Abstract: During pregnancy of some rodents a deep remodeling occurs in the pubic symphysis (PS). In the mouse, these fibrocartilagenousarticulation are gradually replaced by a dense connective tissue, forming the interpubic ligament (IL) at the end of pregnancy. Right after birth, this ligament is rapidly remodeled and the space between the two bones is quickly closed, five days after birth. It is well known that hormones such as relaxin, facilitates the growth and remodeling of organs in female reproductive tract, changing the regulation of biochemical processes that are involved in the remodeling of the extracellular matrix (ECM) of the uterus and cervix during pregnancy. However, little are known about pubic symphysis in when the subject is the involvement of metalloproteinases (MMPs) in this remodeling, as well as the participation of inflammatorycells that could be involved in the remodeling process of the mouse pubic symphysisduring pregnancy. In this study were used pubic symphysis of virgin mice and interpubic ligament in pregnant animais for the detection of MMPs in vivo and at in vitro (24h explants). MMPs from the gelatinase family (MMP-2 and MMP-9) were characterized by zymography and by immunohistochemistryessays, also MMP-8 (collagenase 2) that is believed to be associated almost exclusively with an inflammatory processoTransmission electron microscopy and light microscopy was also used associated with selectively staining, to evidence type of cells that could be involved in the pubic symphysis remodeling. Zymographydemonstratedthe presenceof gelatinases MMP-2 and MMP- 9 both in inactive and active forms, at the PS and IL. Immunohistochemistry,at the pubic symphysis and interpubic ligament, detected the expression of gelatinases and also MMP-8 in cells that were similar to fibroblasts. Morphological characterization evidenciated that cells that are similar to fibroblasts in the pubic symphysis of virgin animais are closely related to the pericellular region, being that during pregnancy,these spaces suffers an increase in this sub-compartment between cell and matrix. Qualitative and quantitative , analysis demonstratedlittle granulocytes in the pubic symphysis of virgin animais and in the interpubic ligament during pregnancy. Results that were obtained from this work support the hypothesis that the gelatinases could be involved in pubic symphysis remodeling through intrinsic processes, being evident that, both cellular phenotype modifications and also chemical modifications of the ECM, are fundamental to the rearrange of this articulation during mouse pregnancy, birth and pos-partum. The extensive remodeling of the ECM suggests hormonal role of the pregnancy in the modulation of the interaction between cell-matrix independently of an inflammatoryreaction in other organs during pregnancy / Mestrado / Histologia / Mestre em Biologia Celular e Estrutural
9

Regressão prostática pós-castração : caracterização das alterações causadas pela privação androgênica e alta dose de 17ß- estradiol / Prostatic regression after castration : characterization of changes by androgen deprivation and high dose 17ß- estradiol

Rosa-Ribeiro, Rafaela, 1987- 21 August 2018 (has links)
Orientador: Hernandes Faustino de Carvalho / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-21T07:59:39Z (GMT). No. of bitstreams: 1 Rosa-Ribeiro_Rafaela_M.pdf: 2991640 bytes, checksum: 1c3d98622022906218832c47353b3c63 (MD5) Previous issue date: 2012 / Resumo: O desenvolvimento, a fisiologia e o câncer de próstata dependem de balanços entre os níveis de andrógenos e estrógenos, que agem via receptor de andrógenos (AR) e receptores de estrógeno (ER'alfa' e ER'beta'), respectivamente. Sabe-se que a cinética de morte das células epiteliais da próstata ventral de ratos (PV) após castração (grupo Cas), administração de alta dose de 17'beta'-estradiol (grupo E2) e combinação de ambos (grupo Cas+E2) é diferenciada, com um nítido efeito aditivo nesta última situação (Garcia-Florez et al, 2005). Neste trabalho, procuramos investigar elementos comuns e exclusivos a estas diferentes condições hormonais, empregando análises morfológicas, estudo de componentes da via AKT/PTEN, e análise da expressão diferencial de genes (utilizando microarranjos de DNA) combinada com identificação de fatores de transcrição (FT) a ela relacionados. O peso relativo da PV foi significativamente diminuído nos grupos Cas e Cas+E2. A castração promove um padrão de descamação das células epiteliais que deve contribuir para redução do número de células epiteliais. No grupo E2, foi marcante a presença agregados protéicos citoplasmáticos e proliferação das células epiteliais com freqüente estratificação do epitélio. Outro aspecto importante foi o descolamento das células musculares lisas do epitélio quando este apresentava dobras epiteliais. No grupo Cas+E2, foram observados os diferentes aspectos observados em cada grupo individual. A análise bioquímica mostrou redução significativa na fosforilação de 4EBP2 nos grupos E2 e Cas+E2 (tendência similar foi observada no grupo Cas). Há uma grande quantidade de genes que são diferencialmente expressos em relação ao controle e que são comuns aos diferentes tratamentos. Surpreendentemente, não houve redução da expressão de probasina no grupo E2. A análise de ontologias e de termos enriquecidos mostrou a ausência de termos enriquecidos no conjunto de genes exclusivos do grupo Cas+E2, o que se concilia bem com a idéia de que os eventos observados neste grupo são aqueles observados nos dois grupos individuais. Em conclusão, a busca por sítios de ligação de FT na região promotora dos genes mais regulados em cada grupo e a identificação de FT nas rede de dos termos enriquecidos indicou os FT Evi-1, NF-Y, HNF-4, Elk-1, GATA-2, c-Rel, v-Myb e NFkB como candidatos a atuarem na regulação dos eventos associados à regressão prostática / Abstract: Prostate development, physiology and cancer depend on a fine balance between the levels of androgens and estrogens acting via the androgen receptor (AR) and the estrogen receptors (ER'alpha' e ER'beta'), respectively. It is known that the kinetics of apoptosis are different in the rat ventral prostate (VP) of castrated rats (Cas group) and in rats subjected to 17'beta'-estradiol high dose (group E2) or their combination (group Cas+E2), with an evident additive effect in the latter situation (Garcia-Florez et al, 2005). In this work, we investigated elements in common and exclusive to each of these hormonal conditions, employing morphological analysis, components of the AKT/PTEN pathway and analyses of differential gene expression using DNA microarrays combined with a search for transcription factors (TF). The VP weight was significantly reduced in the Cas and Cas+E2 groups. In the E2 group, the remarkable effects were the presence of protein aggregates in the cytoplasm, and cell proliferation and layering of the epithelium. Another important aspect was the detachment of the smooth muscle cells from the epithelium when it showed infolds. In the Cas+E2 group, the different aspects observed in the individual groups were observed, except by less frequent epithelial layering. The biochemical analysis showed a significant reduction in 4EBP phosphorylation in the groups E2 and Cas+E2 (similar tendency was observed in the Cas group). There is a large number of differentially expressed genes as compared to the controls and shared by the different treatments, Surprisingly, there was no reduction in the expression of the probasin gene in the E2 group. The recovered gene onthologies and enrichment terms revealed the absence of enrichment terms among the genes exclusive to the Cas+E2 group, what conciliates with the Idea that the observed changes in this group are identical or at least very similar to those occurring in the individual treatments. In conclusion, the search for TF binding sites in the promoter region of the regulated genes and the identification of TF in the regulatory pathways obtained for the enrichement terms indicated the TF Evi-1, NF-Y, HNF-4, Elk-1, GATA-2, c-Rel, v-Myb and NFkB as candidates to regulate the events associated with prostate regression / Mestrado / Biologia Celular / Mestre em Biologia Celular e Estrutural
10

Relação entre biomarcadores inflamatórios, de adesão celular, de estresse oxidativo, de lesão endotelial, remodelamento tecidual e vascular e os diferentes estágios da doença venosa crônica primária (classes clínicas CEAP C0a, C2, C3, C4) / Relationship between biomarkers of inflammation, cell adhesion, oxidative stress, endothelial cell damage, vascular and tissue remodeling and the different stages of primary chronic venous disease (CEAP clinical classes C0a, C2, C3, C4)

Maria das Graças Coelho de Souza 20 August 2013 (has links)
A doença venosa crônica (DVC) é uma desordem complexa que compreende sinais e sintomas que variam das telangiectasias às úlceras ativas. A DVC é classificada de acordo com aspectos clínicos, etiológicos, anatômicos e fisiopatológicos (CEAP) em sete classes variando de C0 à C6. A principal causa da DVC é a hipertensão venosa que altera o fluxo venoso e, consequentemente, a força de cisalhamento que induz alterações fenotípicas nas células endoteliais que passam a expressar mediadores pró-inflamatórios e pró-trombóticos, que levam à adesão de leucócitos, ao aumento do estresse oxidativo, da permeabilidade vascular e do dano endotelial e ao remodelamento tecidual e vascular.Em virtude dos inúmeros mecanismos e da diversidade de moléculas envolvidas na patogênese e progressão da DVC, é essencial conhecer a interação entre elas e também saber quais são as moléculas (biomarcadores) que se correlacionam positivamente ou negativamente com a gravidade da doença. Foram avaliados os níveis de Interleucina-6 (IL-6), sL-selectina, sE-selectina, sP-selectina, molécula de adesão intercelular-1solúvel (sICAM-1), molécula de adesão das células vasculares-1 solúvel (sVCAM-1), ativador tecidual do plasminogênio (tPA), atividade do inibidor do ativador do plasminogênio-1 (PAI-1), trombomodulina solúvel (sTM), fator de von Willebrand (vWF), metaloproteinase de matriz (MMP)-2, MMP-3, MMP-9, inibidor tecidual das MMPs -1 (TIMP-1), angiopoietina-1 e -2, sTie-2 e s-Endoglina e fator de crescimento do endotélio vascular (VEGF) no sangue coletado da veia braquial de 173 mulheres com DVC primária divididas em grupos C2, C3, C4 e C4 menopausadas (C4m) e de 18 voluntárias saudáveis (grupo C0a). Foram também analisados os níveis urinários de ent-prostaglandina F2&#945; nesses grupos. Não foram encontradas diferenças estatisticamente significativas com relação às concentrações sanguíneas e urinárias de sE-selectina, sP-selectina, sICAM-1, atividade de PAI-1, MMP-3, razão TIMP-1/MMP-3, angiopoietin-2, razão angiopoietina-1/angiopoietina-2, s-Endoglina e ent-prostaglandina F2&#945; entre os grupos estudados, possivelmente devido à alta variabilidade na concentração desses biomarcadores entre as participantes do mesmo grupo. Entretanto, as concentrações sanguíneas de IL-6 sL-selectina, sVCAM-1, tPA, vWF, sTM, MMP2, MMP-9, TIMP-1, razão TIMP-1/MMP-2, razão TIMP-1/MMP-9, angiopoietina-1 e VEGF foram estatisticamente diferentes entre os grupos. Não foi identificado nenhum biomarcador que se correlacionasse diretamente ou inversamente com a progressão da DVC, provavelmente devido à diversidade de fatores envolvidos e à complexa interação entre eles durante o curso da doença. / Chronic Venous Disease (CVD) is a complex disorder, which encompasses signs and symptoms that vary from telangiectasias to active ulcers. The CVD is classified according Clinical, Etiologic, Anatomical and Pathophysiological (CEAP) aspects into seven classes varying from C0 to C6. The main cause of CVD is venous hypertension, which alters venous flow and consequently, shear stress. Abnormal shear stress induces phenotypic changes in endothelial cells that start to express pro-inflammatory and pro-thrombotic mediators that lead to leukocyte adhesion, oxidative stress, increased vascular permeability and endothelial cell damage and tissue and vascular remodeling. Due to several mechanisms and the diversity of molecules involved in the pathogenesis and progression of CVD, is essential to know the interplay between them and which are the molecules (biomarkers) that correlate positively and negatively with the severity of the disease. We investigated the levels of interleukin-6 (IL-6), sL-selectin, sE-selectin, sP-selectin, soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), tissue plasminogen activator (tPA), plasminogen activator inhibitor-1 (PAI-1) activity, soluble thrombomodulin (sTM), von Willebrand factor (vWf), matrix metalloproteinase (MMP)-2, MMP-3, MMP-9, tissue inhibitor of metaloproteinases-1 (TIMP-1), angiopoietin-1 and -2, sTie-2, s-Endoglin, vascular endothelial growth factor (VEGF) in the blood taken from the brachial vein of 173 patients with primary CVD divided into C2, C3, C4 and menopaused C4 (C4m) groups and 18 healthy volunteers (C0a group).We also investigated the urinary levels of ent-prostaglandin F2&#945; in these groups. There was no statistically significant difference between groups with respect to blood or urinary levels of sE-selectin, sP-selectin, sICAM-1, PAI-1 activity, MMP-3, TIMP-1/MMP-3 ratio, angiopoietin-2, angiopoietin-1/angiopoietin-2 ratio, s-Endoglin and ent-prostaglandin F2&#945;, likely due to the high variability of these biomarkers concentration among participants within the same group. However, blood levels of IL-6, sL-selectin, sVCAM-1, tPA, vWF, sTM, MMP-2, MMP-9, TIMP-1, TIMP-1/MMP-2 ratio, TIMP-1/MMP-9 ratio, angiopoietin-1 and VEGF were statistically different between groups. It was not identified any biomarker that correlated directly or inversely with the progression of CVD, probably due to the diversity of factors involved and the complex interplay between them in the course of the disease.

Page generated in 0.492 seconds