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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.
351

Efeitos de polimorfismos genéticos sobre as concentrações circulantes de metaloproteinases da matriz extracelular em mulheres com migrânea = Effects of genetic polymorphisms on the circulating concentrations of extracellular matrix metalloproteinases in women with migraine / Effects of genetic polymorphisms on the circulating concentrations of extracellular matrix metalloproteinases in women with migraine

Gonçalves, Flávia Magazoni, 1983- 21 August 2018 (has links)
Orientador: José Eduardo Tanus dos Santos / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-21T14:39:20Z (GMT). No. of bitstreams: 1 Goncalves_FlaviaMagazoni_D.pdf: 13094273 bytes, checksum: b37b538d1e8c37ba2a2ec5c8c99a5a30 (MD5) Previous issue date: 2012 / Resumo: A migrânea é uma cefaleia primária comum e altamente incapacitante que atinge cerca de 10% da população mundial, especialmente as mulheres. Apesar dos esforços, a fisiopatologia da migrânea não está completamente elucidada. No entanto, acredita-se que as metaloproteinases da matriz (MMPs) estejam envolvidas no rompimento da barreira-hematoencefálica durante uma crise de migrânea. O objetivo do presente trabalho é avaliar se polimorfismos funcionais nos genes da MMP-2 (C-1306T e C-735T) e da MMP-9 (C-1562T, -90(CA)n e R(279)Q) e haplótipos estão associados com a migrânea e se eles podem modificar os níveis circulantes de MMPs na migrânea. Para avaliar o efeito de polimorfismos da MMP-9, foram estudadas 102 mulheres sem migrânea (grupo controle) e 187 mulheres com migrânea (141 com migrânea sem aura; MSA e 46 com migrânea com aura; MA). As genotipagens para os polimorfismos C-1562T, -90(CA)n e R(279)Q da MMP-9 foram realizadas por PCR-RFLP, PCR convencional seguida de eletroforese em gel de poliacrilamida e PCR em Tempo Real, utilizando-se o sistema Taqman® para discriminação de alelo, respectivamente. As concentrações plasmáticas de MMP-9 e TIMP-1 foram determinadas por ELISA. Os genótipos para os polimorfismos da MMP-2 foram determinados por PCR em Tempo Real, utilizando-se o sistema Taqman® para discriminação de alelo em 148 mulheres sem migrânea e em 204 mulheres com migrânea (153 MSA e 51 MA). As concentrações plasmáticas da MMP-2 e do TIMP-2 foram avaliadas, respectivamente, por zimografia e por ELISA. Os haplótipos foram inferidos utilizando o programa PHASE. Este estudo é o primeiro a mostrar que polimorfismos funcionais e haplótipos nos genes da MMP-2 e da MMP-9 podem afetar os níveis circulantes das MMPs em pacientes com migrânea. Enquanto o haplótipo H6 (CLQ) da MMP-9 foi associado aos maiores níveis plasmáticos de MMP-9 nas pacientes com migrânea (359,8±69,53ng/ml versus 195,8±9,70ng/ml para o CLR; 201,5±18,67ng/ml para o CHR e 200,2±17,02ng/ml para o CHQ), as maiores concentrações de MMP-2 foram encontradas nas pacientes com migrânea com aura com o genótipo CC para o polimorfismo C-735T (1,29±0,07U.A. versus 0,96±0,06U.A. para os genótipos CT ou TT) e com o haplótipo H1 (CC) (1,24±0,05U.A. versus 0,94±0,05U.A. para o haplótipo CT) no gene da MMP-2. Apesar de não investigarmos os mecanismos moleculares que explicam esses resultados, podemos sugerir que o aumento dos níveis das MMPs associados a genótipos e haplótipos específicos podem predispor essas pacientes a um aumento da permeabilidade vascular da barreira hematoencefálica, promovendo assim o desenvolvimento de um ambiente neuroinflamatório no sistema nervoso central, contribuindo para uma crise de migrânea / Abstract: Migraine is a common primary headache and highly disabling, affecting approximately 10% of the population worldwide, especially women. Despite the efforts, the pathophysiology of migraine is not completely understood. However, it is believed that the matrix metalloproteinases (MMPs) are involved in the disruption of blood-brain barrier (BBB) during migraine attacks. The aim of this study was to evaluate whether functional polymorphisms in MMP-2 (C-1306T and C-735T) and MMP-9 (C-1562T, -90(CA)n and R(279)Q) genes and haplotypes are associated with migraine and whether they modify circulating MMPs levels in migraine. To evaluate the effect of MMP-9 polymorphisms, we studied 102 healthy women (controls) and 187 women with migraine (141 migraine without aura; MWA, and 46 migraine with aura; MA). Genotypes for C-1562T, -90(CA)n e R(279)Q MMP-9 polymorphisms were determined by PCR-RFLP, by conventional PCR followed by electrophoresis in polyacrylamide gels and by real time-PCR using Taqman® allele discrimination assays, respectively. The plasma MMP-9 and TIMP-1 concentrations were measured by ELISA. Genotypes for MMP-2 polymorphisms were determined by real time-PCR using Taqman® allele discrimination assays in 148 healthy women without history of migraine and in 204 women with migraine (153 MWA and 51 MA). The plasma concentrations of MMP-2 and TIMP-2 were evaluated by gelatin zymography and ELISA, respectively. Haplotypes were inferred using the PHASE program. This is the first study to show that functional MMP-2 and MMP-9 polymorphisms and haplotypes can affect the circulating MMPs levels in patients with migraine. While the MMP-9 H6 (CLQ) haplotyple is associated with high MMP-9 concentrations in patients with migraine (359,8±69,53ng/ml versus 195,8±9,70ng/ml for CLR; 201,5±18,67ng/ml for CHR and 200,2±17,02ng/ml for CHQ) , the highest concentrations of MMP-2 were found in patients with migraine with aura carrying the CC genotype for C-735T polymorphism (1,29±0,07A.U. versus 0,96±0,06A.U. for CT or TT genotypes) and the H1 (CC) haplotype (1,24±0,05A.U. versus 0,94±0,05A.U. for CT haplotype) in the MMP-2 gene. Although we have not investigated the molecular mechanisms explaining these results, we can suggest that an increase of the MMPs levels associated with these genotypes and haplotypes may predispose these patients to increased vascular BBB permeability, thus promoting the development of an inflammatory environment in their central nervous systems, which contributes to migraine attacks / Doutorado / Farmacologia / Doutora em Farmacologia
352

Matrix metalloproteinases (MMPs) in oral carcinomas

Ylipalosaari, M. (Merja) 18 May 2005 (has links)
Abstract Matrix metalloproteinases, MMPs, are a family of enzymes capable of modulating connective tissue components. The expression of several MMPs is increased in oral squamous cell carcinomas (OSCCs). They are assumed to have an important role in the development and progression of OSCCs. However, the exact role and mechanism of the regulation of MMPs in malignant transformation are still largely unknown. In this study, tumour-associated trypsin-2 (TAT-2) was detected in OSCC tissue sections, and its role in MMP-2 and -9 regulation in carcinoma cells was evaluated. The TAT-2 gene was transfected into two different OSCC cell lines and one immortalized oral epithelial cell line. In TAT-2-transfected cells, MMP-9 activation increased OSCC cell invasion in chicken chorionallantoic membrane assay. Increased intravasation was prevented by tumour-associated trypsin inhibitor or specific gelatinase-inhibiting CTT-peptide. TAT-2 also converted MMP-1, -8, -13 and -3 into smaller molecular weight forms in vitro. However, TAT-2-transfected OSCC cells showed no conversion. TAT-2 was demonstrated to degrade powerfully type I collagen into small fragments in vitro. The cell surface receptor αvβ6 integrin is strongly up-regulated in OSCCs. By using β6-transfected OSCC cells, it was demonstrated that αvβ6 integrin down-regulates MMP-13 expression. However, this integrin did not regulate other collagenases or TIMP-1. β6-transfected cells invaded more efficiently through the basement membrane matrix, but their migration through type I collagen remained unchanged. MMP-8 expression was detected for the first time in head and neck squamous cell carcinoma (HNSCC) cell lines and corresponding cultured dermal and tumour fibroblasts. The localization of MMP-8 in HNSCC was determined by immunohistochemical stainings and in situ hybridization. MMP-8 production levels in carcinoma cells were faint and sporadic in HNSCCs sections. Ninety-two primary mobile tongue SCCs were subjected to MMP-8 immunohistochemical staining, and the staining results were compared to survival rates. MMP-8 was associated with improved disease-free survival in females but not in males.
353

Genetic and molecular background of ascending aortic aneurysms

Huusko, T. (Tuija) 14 May 2013 (has links)
Abstract Thoracic aortic aneurysms (TAAs) are a significant source of morbidity and mortality. Classical risk factors for TAAs are hypertension, atherosclerosis, male gender, smoking, age, high body mass index, family history and chronic obstructive pulmonary disease. In addition, in certain cases of TAAs, i.e., ascending aortic aneurysms (AscAA), genetic factors are highly prominent. Matrix metalloproteinases are in a major role in the destruction of the aortic wall and the imbalance between matrix metalloproteinases, and their inhibitors are involved in the formation of aneurysms. In addition, osteopontin is a potent regulator of matrix metalloproteinases and it is widely expressed in injured arteries. Recently, telomere shortening has been shown to be involved in the development of abdominal aortic aneurysms (AAA). In this aneurysm type, atherosclerosis has a major role. Since atherosclerosis is frequently absent in the case of TAAs, the length of telomeres was measured in the blood samples of TAA patients. The purpose of this thesis was to study the genetic background of TAAs of the ascending aorta and furthermore, the molecular background of this disease. The first study was done with families with TAAs, and dissections and one chromosomal locus (5q13-14) of the studied seven loci showed a significant genetic linkage for TAAs. Two other studies were done exploiting our TAA case-control material. Study II showed elevated levels of osteopontin, matrix metalloproteinase type 2 and 9 in the plasma and tissue samples of TAA patients compared with controls. In the third study, longer blood leukocyte telomeres were found in the DNA samples of TAA patients compared with controls; furthermore, the elevation of telomere lengthening protein telomerase expression was found in the tissue samples of TAA patients. This thesis presents region 5q13-14 as a potential genetic regulator for TAAs in Finnish families. In addition, elevated levels of osteopontin, matrix metalloproteinase type 2 and 9 can be considered as a plasma biomarker for aneurysmal disease. Furthermore, longer blood leukocytes were found to be a significant risk factor for developing TAAs. / Tiivistelmä Rinta-aortan aneurysmat ovat merkittävä sairastumisiin ja kuolemiin johtava tekijä. Perinteisinä riskitekijöinä aneurysmille on pidetty korkeaa verenpainetta, ateroskleroosia, miessukupuolta, tupakointia, ikää, ylipainoa, suvussa esiintyneitä aneurysmatapauksia ja keuhkoahtaumatautia. Näiden lisäksi erityisesti nousevan rinta-aortan alueella esiintyvissä aneurysmissa myös perinnöllisillä tekijöillä on korostunut merkitys. Matriksimetalloproteinaaseilla ja niiden estäjillä on merkittävä rooli, kun aortan seinämää hajotetaan. Tasapainon järkkyminen kyseisten proteiinien keskinäisessä suhteessa voi johtaa aneurysman muodostumiseen. Myös osteopontiinin tiedetään olevan tehokas matriksimetalloproteinaasien säätelijä, ja sitä tuotetaankin yleisesti vahingoittuneessa verisuonessa. Telomeerien lyhentyminen on vastikään yhdistetty vatsa-aortan alueella esiintyviin aneurysmiin, joissa ateroskleroosilla on yleensä merkittävä rooli. Koska ateroskleroosi on vain harvoin nousevan rinta-aortan alueen aneurysmien taustalla, rinta-aortan aneurysmapotilaiden valkosolujen telomeerien suhteelliset pituudet määritettiin. Väitöskirjan ensimmäisessä osatyössä keskityttiin löytämään geneettinen kytkentä rinta-aortan aneurysmien ja jonkin seitsemän tutkitun kromosomialueen välille. Geneettinen kytkentä löydettiin kromosomialueelta 5q13-14. Osatöissä 2 ja 3 hyödynnettiin rinta-aortan aneurysmien potilas- ja verrokkiaineistoja. Osatyö 2 osoitti, että matriksimetalloproteinaasien (2 ja 9) määrät ovat kohonneet rinta-aortan aneurysmapotilaiden näytteissä verrokkeihin verrattuna. Osatyössä 3 telomeerien suhteelliset pituudet veren valkosoluissa olivat pidemmät nousevan rinta-aortan aneurysmapotilaiden näytteissä verrokkihenkilöiden näytteisiin verrattuna. Myös telomeraasin tuotto oli lisääntynyt rinta-aortan aneurysmapotilaiden aorttakudosnäytteissä. Väitöskirjassa esitetään tuloksena kromosomialue 5q13-14 geneettisenä säätelijänä suomalaisissa suvuittain esiintyvissä rinta-aortan aneurysmatapauksissa. Kohonneita matriksimetalloproteinaasien ja osteopontiinin tasoja voidaan lisäksi pitää biomarkkereina rinta-aortan aneurysmien sairastavuudelle. Veren valkosolujen pidemmät telomeerit näyttävät myös olevan yhteydessä rinta-aortan aneurysmien sairastavuuteen.
354

Métalloprotéases matricielles et maladie d'Alzheimer : étude du rôle de MT1-MMP dans le métabolisme de l'APP/Aß / Matrix metalloproteinases and Alzheimer disease : involvement of MT1-MMP in APP/Abeta metabolism

Py, Nathalie 16 December 2014 (has links)
La maladie d'Alzheimer (MA) est la maladie neurodégénérative la plus répandue à travers le monde et reste actuellement incurable. Le peptide beta amyloïde (Abeta), composant principal des plaques séniles retrouvées dans le cerveau des patients, joue un rôle majeur dans le développement de la MA, d'où l'importance de contrôler sa production et/ou son élimination. Dans cette optique, nous travaillons sur des molécules nommées métalloprotéases matricielles (MMPs). Bien qu'ayant été impliquées à la fois dans de nombreux processus physiologiques et pathologiques dans système nerveux, leur rôle dans la MA reste encore relativement inexplorée. Nous avons utilisé comme modèle d'étude des souris qui développent les symptômes de la MA (déclin cognitif, mort des neurones). Nous montrons que deux MMPs, MMP-2 et MT1-MMP, augmentent leurs niveaux d'expression avec le vieillissement de l'animal et donc avec l'aggravation de la pathologie. Ceci a lieu dans l'hippocampe, une région du cerveau qui est particulièrement sensible car elle est impliquée dans l'apprentissage et la mémoire. Par la suite nous avons utilisé des cellules HEKswe qui produisent beaucoup d'Abeta et miment d'une certaine manière ce qui se passe dans le cerveau de la souris, afin de mieux appréhender la signification des augmentations de ces MMPs. Nous montrons que la surexpression de MT1-MMP dans ces cellules favorise la formation d'Abeta, alors que MMP-2 l'empêche. Ces résultats montrent pour la première fois une dualité fonctionnelle au sein de la famille des MMPs, et plus important, révèlent une nouvelle molécule amyloïdogénique (MT1-MMP) qui pourrait devenir à terme une cible thérapeutique. / We investigate the role of matrix metalloproteinases in the metabolism of beta amyloid peptide (Abeta) and its amyloid precursor protein (APP) in Alzheimer's disease (AD). Our results in the 5xFAD mouse model of AD indicate a cell-type and age-dependent upregulation of MMP-2 -and MT1-MMP active forms. This is concomitant with the increase of toxic forms of Abeta, but also of cytotoxic C99, a membrane fragment of APP generated by beta-secretase and that gives rise to Abeta after gamma-secretase cleavage. We show in HEK cells overproducing Abeta that while MT1-MMP interacts with APP and boosts C99 and Abeta production, MMP-2 does not interact with APP and degrades Abeta. These results uncover a MMP-specific regulatory crosstalk with amyloid and also MT1-MMP as a new pro-amyloidogenic proteinase. We want now to gain further insight into the mechanisms that support MT1-MMP effects, namely the possible modulation by MT1-MMP of beta- and gamma-secretase activities and/or APP trafficking.
355

Caracterização de disintegrinas de venenos viperídeos como ferramentas seletivas na detecção ou inibição da função de integrinas / Characterization of viper venom disintegrins as tools for detecting and inhibiting integrin function

Diego Alberto Butera Wadsworth 15 December 2003 (has links)
As integrinas são proteínas de membrana envolvidas em diversos processos biológicos como embriogênese, inflamação e agregação plaquetária. A alteração de seu padrão de expressão está relacionada com processos patológicos como trombose e câncer, fazendo das integrinas ótimos indicadores da progressão destas doenças. Assim, a integrina α2β1 pode ser considerada como indicadora de angiogênese, sendo expressa nas células endoteliais durante o crescimento de novos vasos. Já a ausência da αIIbβ3 em plaquetas está relacionada com a doença de Glanzmann, caracterizada por uma agregação plaquetária deficiente, e sua presença em outros tipos celulares está relacionada com processos de metástase e invasão de tecidos. Estas integrinas contêm antagonistas naturais nos venenos de serpentes da família VIPERlDAE: As RGD-disintegrinas bloqueiam a integrina αIIbβ3 e as ECD-disintegrinas bloqueiam a integrina α2β1. Estas últimas formam parte de metaloproteinases com múltiplos domínios de aproximadamente 50 kDa. Interessados em desenvolver marcadores moleculares para estas integrinas, direcionamos nossos objetivos para: (1) a elucidação da região mínima das ECD-disintegrinas com atividade biológica e (2) construção de biomarcadores para a integrina α2β1 utilizando a região elucidada, e para a integrina αIIbβ3 utilizando uma RGD-disintegrina. Neste trabalho conseguimos determinar uma região de 49 resíduos na porção C-terminal do domínio ECD-disintegrina da jararagina que reage com um anticorpo neutralizante das atividades hemorrágica e de ligação ao colágeno da proteína. Esta região foi subclonada e expressa em fusão com a fosfatase alcalina de E. colí, mas não teve funcionalidade como marcador. No entanto, a RGD-disintegrina eristostatina em fusão com a fosfatase alcalina mostrou bifuncionalidade, apresentando tanto atividade disintegrina como atividade catalítica. Além disso, verificamos sua seletividade pela integrina αIIbβ3 e padronizamos um ensaio direto de dot blot para a presença dessa integrina em plaquetas, com um único passo de incubação. / Integrins are membrane proteins involved in biological processes such as embriogenesis, inflammation and platelet aggregation. The alteration of their expression pattem is related to pathological disorders such as thrombosis and cancer, making integrins suitable indicators of the progression of these diseases. Thus, the α2β1 integrin, which is expressed in endothelial cells during capillary growth, may be an indicator of angiogenesis. The absence of αIIbβ3 integrin in platelets is related to Glanzmann disease, characterized by defective platelet aggregation and its expression in other cellular types is related with metastasis and tissue-invasion processes. These integrins contain natural antagonists in venoms from the VIPERIDAE snake family: RGD-disintegrins, which block the αIIbβ3 integrin and ECD-disintegrins, which block the α2β1 integrin. The latter forming part of multidomain metalloproteinases of approximately 50 kDa. In order to develop molecular markers for integrins, we have directed our objectives at: (1) determining the minimal region of ECD-disintegrins with biological activity and (2) engineering biomarkers for the α2β1 integrin using the previously determined minimal region and for the αIIbβ3 using an RGD-disintegrin. In this work we have determined a 49-residue region located in the C-terminus of jararhagin ECD-disintegrin domain, which reacts with a neutralizing antibody of hemorrhagic and binding to collagen activities of the protein. This region was subcloned and expressed in fusion with E. coli alkaline phosphatase, but did not present a marker activity. On the other hand, the RGD-disintegrin eristostatin fused to alkaline phosphatase showed bifunctionality, presenting both, disintegrin and catalytic activities. Furthermore, we have characterized its selectivity for the αIIbβ3 integrin and we have standardized a direct dot blot assay with one-step incubation for the presence of this integrin in platelets.
356

Buněčná a molekulární charakterizace selhaných transplantátů lidské rohovky. Role matrix metaloproteináz při opakované keratolýze lidské rohovky. / Cell and Molecular Characterization of Failed Human Corneal Grafts. The Role of Matrix Metalloproteinases in Recurrent Corneal Melting.

Brejchová, Kristýna January 2011 (has links)
The aim of this work was to investigate the contribution of matrix metalloproteinases (MMPs) to recurrent corneal melting. Twenty three melted corneas from seven patients were separated into three groups: a) patients with primary Sjögren's syndrome, b) those with rheumatoid arthritis and c) those with other corneal melting underlying pathologies. Eleven cadaverous corneas served as controls. The presence of MMP-1, -2, -3, -7, -8, -9, and -13 was detected using indirect enzyme immunohistochemistry. The active forms of MMP-2 and -9 and MMP- 3 and -7 were examined by gelatin and casein zymography, respectively. The concentrations of active MMP-1 and -3 were measured using activity assays. Increased immunostaining intensity for MMP-1, -2, -3, -7, -8 and -9 was shown in the corneal epithelium and the stroma of almost all melted corneas from all three groups compared to the negative or slightly positive staining of the controls. In the endothelium, immunostaining for MMP-2 and MMP-9 was increased in most specimens of groups II and III and group I, respectively. A markedly higher level of active MMP-2 was detected in six, and active MMP-9 in all, pathologic specimens compared to the controls. In contrast to the completely negative controls, the proenzymes of MMP-3 and -7 were detected in almost all melted...
357

MMP-Degradable Biosensors: Applications in Drug Delivery and Personalized Medicine

Deshmukh, Ameya January 2020 (has links)
No description available.
358

Insights into Early-Pregnancy Mechanisms: Mast Cells and Chymase CMA1 Shape the Phenotype and Modulate the Functionality of Human Trophoblast Cells, Vascular Smooth-Muscle Cells and Endothelial Cells

Zhang, Ningjuan, Schumacher, Anne, Fink, Beate, Bauer, Mario, Zenclussen, Ana Claudia, Meyer, Nicole 13 June 2023 (has links)
Spiral-artery (SA) remodeling is a fundamental process during pregnancy that involves the action of cells of the initial vessel, such as vascular smooth-muscle cells (VSMCs) and endothelial cells, but also maternal immune cells and fetal extravillous trophoblast cells (EVTs). Mast cells (MCs), and specifically chymase-expressing cells, have been identified as key to a sufficient SA remodeling process in vivo. However, the mechanisms are still unclear. The purpose of this study is to evaluate the effects of the MC line HMC-1 and recombinant human chymase (rhuCMA1) on human primary uterine vascular smooth-muscle cells (HUtSMCs), a human trophoblast cell line (HTR8/SV-neo), and human umbilical-vein endothelial cells (HUVEC) in vitro. Both HMC-1 and rhuCMA1 stimulated migration, proliferation, and changed protein expression in HUtSMCs. HMC-1 increased proliferation, migration, and changed gene expression of HTR8/SVneo cells, while rhuCMA treatment led to increased migration and decreased expression of tissue inhibitors of matrix metalloproteinases. Additionally, rhuCMA1 enhanced endothelial-cell-tube formation. Collectively, we identified possible mechanisms by which MCs/rhuCMA1 promote SA remodeling. Our findings are relevant to the understanding of this crucial step in pregnancy and thus of the dysregulated pathways that can lead to pregnancy complications such as fetal growth restriction and preeclampsia.
359

COLLECTIVE CELL MIRATION DURING HEART MORPHOGENESIS IN DROSOPHILA REQUIRES GUIDANCE SIGNALING AND EXTRACELLULAR MATRIX REMODELLING / COLLECTIVE CELL MIGRATION OF CARDIOBLASTS DURING HEART MORPHOGENESIS

Raza, Qanber 11 1900 (has links)
Collective cell migration is a defining feature of many morphogenetic processes. Diseases such as congenital heart diseases and cancer arise due to mis-regulation of collective migratory behaviour and animal models have played a pivotal role in dissecting the molecular mechanisms which underlie this process. During embryonic heart development, cardiac precursors undergo a stage of collective migration in both vertebrates and invertebrates. We developed a paradigm to quantitatively assess collective cell migration of cardiac precursors in live embryos of Drosophila, which is the simplest genetic model organism with a heart. Therefore, we studied processes which are commonly observed in most collective cell migration models such as guidance signalling and extracellular matrix remodelling. Our results demonstrate that leading edge of migrating cardioblasts is highly active and that this behaviour is regulated by guidance cues, Slit and Netrin and their respective receptors Robo/Robo2 and Frazzled/Uncoordinated5. These molecules cooperatively promote leading edge motility and epithelial characteristics of the cardioblasts. Next, we determined that matrix restructuring around the cardioblasts requires proteases Mmp1 and Mmp2, which are members of the highly conserved Matrix Metalloproteinase family. We demonstrate that Mmp1 and Mmp2 have distinct roles during lumen formation, however, both Mmp1 and Mmp2 are required for collective motility of the cardioblast leading edge. Hence, we propose that embryonic heart development in Drosophila is an effective and amenable model of collective cell migration which can be applied to discover unique mechanisms which coordinate cell movement in groups. / Thesis / Doctor of Philosophy (PhD)
360

MACROPHAGE MIGRATION INHIBITORY FACTOR AND LIVER DISEASE: THE ROLE OF MIF IN ALCOHOL-INDUCED LIVER INJURY AND CARBON TETRACHLORIDE (CCI4)-INDUCED LIVER FIBROSIS

Barnes, Mark Aaron, Jr 11 June 2014 (has links)
No description available.

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