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Correlação entre achados clínicos e histopatológicos com aqueles da imunofluorescência direta no diagnóstico de lúpus eritematoso discoide canino / Correlation between clinical and histopathological findings with those of direct immunofluorescence in the diagnosis of canine discoid lupus erythematosusOdaguiri, Juliana 10 December 2013 (has links)
O lúpus eritematoso discoide (LED) é a variante mais comum do Complexo Lúpus Eritematoso, sendo considerado uma das dermatopatias imunemediadas mais evidenciadas em cães, ficando muito próximo à casuística do pênfigo foliáceo. É afecção, relativamente, benigna sem envolvimento sistêmico e, clinicamente, caracterizada por leucodermia e/ou eritema associado à perda do aspecto em \"calçamento de pedras\" do plano nasal e, imunologicamente, pela deposição de autoanticorpos (IgA, C3, IgM e IgG) na zona da membrana basal (ZMB). O presente estudo visa correlacionar os achados clínicos e histopatológicos com aqueles da imunofluorescência direta (IFD), objetivando aumentar a acurácia do diagnóstico do LED. Foram incluídos 11 cães (Grupo I) com o quadro lesional tegumentar característico do LED e, cinco caninos (Grupo II), dermatologicamente hígidos, para o controle negativo da IFD. Fragmentos cutâneos oriundos do plano nasal foram submetidos ao exame histopatológico e à reação da IFD e, os resultados obtidos em ambos os Grupos, I e II, foram analisados estatisticamente pelo Índice kappa (k) visando a determinação do grau de concordância ou confiabilidade entre os dois métodos diagnósticos. No Grupo I, o diagnóstico de LED foi firmado em 100% (11/11) dos animais, pela reação de IFD, enquanto que o exame histopatológico estabeleceu o diagnóstico em 81,8% (9/11) dos casos. A positividade da IFD para o LED canino foi estabelecida, em sua totalidade, a partir da fluorescência esverdeada evidenciada na ZMB e/ou em seus anexos cutâneos e, os imunoreagentes mais frequentemente encontrados foram a IgM e C3. Já, em relação ao Grupo II, na totalidade dos animais não se evidenciou histopatologicamente qualquer alteração tegumentar.Também, pela IFD os resultados mostraram-se negativos. O substancial grau de concordância entre a IFD e a histopatologia (k= 0,738 e p= 0,002) comprova que a reação de imunofluorescência direta é exequível e útil no estabelecimento do diagnóstico do LED canino. / The discoid lupus erythematosus (DLE) is the most common variant of the Complex Lupus Erythematosus, considered one of auto-immune skin diseases more evident in dogs, getting very close to the casuistry of pemphigus foliaceus. The disease is relatively benign and without systemic involvement, clinically characterized by leukoderma and / or erythema associated with loss of the normal planum nasale \"cobblestone \" architecture and immunologically by deposition of autoantibodies (IgA, C3, IgM and IgG) at the basement membrane zone (BMZ). This study aims to correlate the clinical and histopathological findings with those of direct immunofluorescence (DIF), aiming to increase the accuracy of diagnosis DLE. We included 11 dogs (Group I) with cutaneous lesions characteristic of DLE and five dogs (Group II), with no cutaneous alterations, for the negative DIF. Cutaneous fragments derived from the planum nasale were submitted to histopathological examination and DIF, and the results obtained in both Groups I and II were analyzed by kappa index (k) in order to determine the degree of agreement or reliability among two methods. In Group I, the diagnostic DLE was established in 100 % (11/11) of animals, by the reaction of DIF, while the histopathological examination confirmed the diagnosis in 81.8 % (9/11) of cases. The positive DIF for DLE canine was established, in its totality, from the greenish fluorescence evident in the BMZ and / or on their skin annexes and the immunoreagents most frequently found were IgM and C3. Now, in relation to the Group II, all animals did not reveal any histopathological tegumentar changes. Also, by the DIF results were negative. The substantial degree of agreement between the DIF and histopathology (k = 0.738 and p = 0.002) shows that the direct immunofluorescence assay is feasible and useful in establishing the diagnosis of canine DLE.
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Novel Uses for Ultrasound as Both an Imaging and Therapeutic Tool in the Characterization and Percutaneous Revascularization of Chronic Total OcclusionThind, Amandeep 14 November 2011 (has links)
Revascularization of Chronic Total Occlusions (CTO) by percutaneous coronary interventions is limited by low success rates, primarily due to difficulty in guidewire crossing. There are a number of contributing factors that make guidewire crossing challenging. Two of the most significant impediments are: a) inability to adequately visualize the CTO to appropriately plan a pathway to the distal lumen, and b) difficulty in physically crossing the rigid endcap at the proximal end of CTO without using stiff wires. Moreover, there is a significant knowledge gap in the composition of CTOs, and the consequent impact of that composition on crossability.
This thesis presents tools and techniques to help mitigate the current shortcomings, while shedding new light on CTO composition and maturation. The tools and techniques presented herein are based upon ultrasound approaches with the intent of eventually developing these strategies into catheter based solutions.
Recent studies have suggested that the presence of microvessels in CTO may provide a preferred pathway for guidewire crossing. However, due to limited resolution and a lack of soft tissue contrast in angiography, microvessels within CTO cannot generally be detected by in-vivo angiographic techniques, and when they are visualized, it is unknown whether or not they are intraluminal. In this thesis, high frequency ultrasound with Power Doppler overlays is shown to be capable of detecting and tracking transluminal recanalization channels using an in vivo porcine model of CTO. It is also shown that ultrasound is a more sensitive technique to detect and map these channels than MRI. Furthermore, features of microvasculature in CTOs that had not previously been seen are presented.
A technique was then developed to facilitate guidewire crossing through the proximal endcap, also known as the proximal fibrous cap (PFC). In order to assess the ease with which a probe is able to
iv
perforate the PFC, a system was designed and to measure the force required for PFC puncture. This system was validated by examining the required puncture forces for CTOs of different ages. It was shown that CTOs less than 6 weeks in age are significantly easier to puncture than those greater than 12 weeks. This coincides with differences in composition, with the presence of softer materials at the earlier time point, such as thrombus and proteoglycans compared to stiffer fibrotic materials which predominate at late timepoints.
After development and validation of a reliable technique to measure ease of PFC puncture, the efficacy of therapies designed to modify PFC compliance could be assessed. The use of ultrasound mediated microbubble (UMM) disruption to act as an adjuvant to accelerate collagenase therapy in CTO was examined. A significant reduction in puncture force and an increase in the amount of collagen degraded was achieved using a combined UMM + collagenase treatment compared with collagenase therapy alone and UMM treatment alone.
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Novel Uses for Ultrasound as Both an Imaging and Therapeutic Tool in the Characterization and Percutaneous Revascularization of Chronic Total OcclusionThind, Amandeep 14 November 2011 (has links)
Revascularization of Chronic Total Occlusions (CTO) by percutaneous coronary interventions is limited by low success rates, primarily due to difficulty in guidewire crossing. There are a number of contributing factors that make guidewire crossing challenging. Two of the most significant impediments are: a) inability to adequately visualize the CTO to appropriately plan a pathway to the distal lumen, and b) difficulty in physically crossing the rigid endcap at the proximal end of CTO without using stiff wires. Moreover, there is a significant knowledge gap in the composition of CTOs, and the consequent impact of that composition on crossability.
This thesis presents tools and techniques to help mitigate the current shortcomings, while shedding new light on CTO composition and maturation. The tools and techniques presented herein are based upon ultrasound approaches with the intent of eventually developing these strategies into catheter based solutions.
Recent studies have suggested that the presence of microvessels in CTO may provide a preferred pathway for guidewire crossing. However, due to limited resolution and a lack of soft tissue contrast in angiography, microvessels within CTO cannot generally be detected by in-vivo angiographic techniques, and when they are visualized, it is unknown whether or not they are intraluminal. In this thesis, high frequency ultrasound with Power Doppler overlays is shown to be capable of detecting and tracking transluminal recanalization channels using an in vivo porcine model of CTO. It is also shown that ultrasound is a more sensitive technique to detect and map these channels than MRI. Furthermore, features of microvasculature in CTOs that had not previously been seen are presented.
A technique was then developed to facilitate guidewire crossing through the proximal endcap, also known as the proximal fibrous cap (PFC). In order to assess the ease with which a probe is able to
iv
perforate the PFC, a system was designed and to measure the force required for PFC puncture. This system was validated by examining the required puncture forces for CTOs of different ages. It was shown that CTOs less than 6 weeks in age are significantly easier to puncture than those greater than 12 weeks. This coincides with differences in composition, with the presence of softer materials at the earlier time point, such as thrombus and proteoglycans compared to stiffer fibrotic materials which predominate at late timepoints.
After development and validation of a reliable technique to measure ease of PFC puncture, the efficacy of therapies designed to modify PFC compliance could be assessed. The use of ultrasound mediated microbubble (UMM) disruption to act as an adjuvant to accelerate collagenase therapy in CTO was examined. A significant reduction in puncture force and an increase in the amount of collagen degraded was achieved using a combined UMM + collagenase treatment compared with collagenase therapy alone and UMM treatment alone.
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Tumor stroma in anaplastic thyroid carcinoma interstitial collagen and tumor interstitial fluid pressure /Lammerts, Ellen, January 2001 (has links)
Diss. (sammanfattning) Uppsala : Univ., 2002. / Härtill 4 uppsatser.
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Avaliação das atividades citotóxica, genotóxica e sobre a proliferação celular do óleo-resina de eperua oleifera (fabaceae)Gomes, Fernanda Torlania Alves 14 April 2014 (has links)
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Previous issue date: 2014-04-14 / FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas / There is a growing demand of using plants from the Amazon to the development of drugs and
cosmetics. The Eperua genus belongs to the family Fabaceae and consists of 14 species
distributed from Central Amazonia. The oil-resin extracted from the trunk of Eperua has been
used in popular medicine similarly to the copaiba oil as healing, antibacterial and antifungal.
Very few studies have been conducted in order to test the biological activities of the oil-resin
of these species. This study aimed to investigate the effects of the acid fraction of E.oleifera
oil-resin on cell proliferation, collagen production in human fibroblasts, inhibition of
metalloproteinases and cytotoxicity against malignant cell lines. It was evaluated the effects
of the oil-resin on the morphology, proliferation and collagen production in fibroblast cells
MRC-5 and FPH. There was a reduction of cell proliferation of fibroblast cells treated with
the oil-resin at a concentration of 5 µg/mL. The induction of collagen production in
fibroblasts was significant in the treatments performed above 2.5 µg/mL relative to untreated
cells. Additionally, the cytotoxicity of the oil was evaluated on three lines and six neoplastic
and three non-neoplastic cell line. The results showed significant cytotoxicity against all lines,
with IC50 values between (13 - 50 µg/mL). The evaluation of the hemolytic potential of the
oil-resin showed high toxicity in erythrocytes of Swiss mice Mus musculus, with IC50 = 38.29
µg/mL. According to the comet assay, the acid fraction of E. oleifera oil-resin induced
genotoxicity in MRC-5 cells with DNA damage index between (40 - 60 %) when compared to
the negative controls (0-20%). Inhibitory action of the oil-resin was observed in the
concentration-dependent manner on collagenase activity, with IC50 = 46.64 µg/mL. The
zymography assay testing the activity of MMP - 2 and MMP – 9 from HaCaT cells, showed
little significant enzymatic inhibition, because of its not viable treatment in high
concentrations. Results showed that the acid fraction of E. oleifera oil-resin showed cytotoxic,
genotoxic and hemolytic effects, and collagenase inhibition. Taken together, our data suggests
that E. oleifera could be considered as a source of new therapeutic drug, by isolating the
active compounds and possibly decreasing the undesirable toxic side effects. / É crescente a demanda do uso de plantas da Amazônia para o desenvolvimento de fármacos e
cosméticos. O gênero Eperua, pertencente à família Fabaceae, é constituído por 14 espécies
distribuídas pela Amazônia Central. O óleo-resina extraído do tronco das árvores deste gênero
tem sido utilizado na medicina popular de modo similar ao da copaíba, como cicatrizante,
antifúngico e bactericida. Pouquíssimos estudos foram realizados com o propósito de testar
as atividades biológicas do óleo-resina destas espécies. O presente trabalho objetivou
investigar os efeitos da fração ácida do óleo-resina de Eperua oleifera na proliferação celular
e produção de colágeno em fibroblastos humanos, inibição de metaloproteinases e
citotoxicidade contra linhagens celulares tumorais e não tumorais. Foram avaliados os efeitos
do óleo na morfologia, proliferação e produção de colágeno em fibroblastos das linhagens
FPH e MRC-5. Foi avaliada a citotoxicidade da fração ácida do óleo-resina sobre seis
linhagens neoplásicas e três linhagens não neoplásicas. Houve significativa citotoxicidade do
óleo contra todas as linhagens avaliadas, com valores de CI50 entre (13 - 50 µg/mL). A
indução da produção de colágeno em fibroblastos foi significativa nos tratamentos realizados
a partir de 2,5 µg/mL. Houve redução da proliferação celular nos tratamentos com o óleoresina
na concentração de 5 µg/mL. A avaliação do potencial hemolítico do óleo indicou
toxicidade em eritrócitos de camundongos suiços Mus musculus, com valor de CI50 = 38,29
µg/mL. O teste do cometa indicou que o óleo induziu genotoxicidade nas células MRC-5 com
índice de dano no DNA entre (40 – 60%) nas concentrações de 7,5 - 30 µg/mL. Foi
observada ação inibitória do óleo-resina na atividade de colagenases de forma concentraçãodependente,
com CI50 = 46,64 µg/mL. Ensaios zimográficos da atividade de MMP-2 e MMP-9
de células HaCaT não indicaram importante inibição enzimática quando avaliadas em baixas
concentrações do óleo-resina. Os resultados obtidos evidenciaram que a fração ácida do óleoresina
de E. oleifera apresentou efeito citotóxico, genotóxico, hemolítico, e inibidor de
colagenases. Face ao exposto, nossos dados sugerem que E. oleifera pode vir a ser
considerada uma fonte de novos agentes quimioterapêuticos, por meio do isolamento dos
compostos ativos e, possível diminuição dos efeitos tóxicos indesejáveis.
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Correlação entre achados clínicos e histopatológicos com aqueles da imunofluorescência direta no diagnóstico de lúpus eritematoso discoide canino / Correlation between clinical and histopathological findings with those of direct immunofluorescence in the diagnosis of canine discoid lupus erythematosusJuliana Odaguiri 10 December 2013 (has links)
O lúpus eritematoso discoide (LED) é a variante mais comum do Complexo Lúpus Eritematoso, sendo considerado uma das dermatopatias imunemediadas mais evidenciadas em cães, ficando muito próximo à casuística do pênfigo foliáceo. É afecção, relativamente, benigna sem envolvimento sistêmico e, clinicamente, caracterizada por leucodermia e/ou eritema associado à perda do aspecto em \"calçamento de pedras\" do plano nasal e, imunologicamente, pela deposição de autoanticorpos (IgA, C3, IgM e IgG) na zona da membrana basal (ZMB). O presente estudo visa correlacionar os achados clínicos e histopatológicos com aqueles da imunofluorescência direta (IFD), objetivando aumentar a acurácia do diagnóstico do LED. Foram incluídos 11 cães (Grupo I) com o quadro lesional tegumentar característico do LED e, cinco caninos (Grupo II), dermatologicamente hígidos, para o controle negativo da IFD. Fragmentos cutâneos oriundos do plano nasal foram submetidos ao exame histopatológico e à reação da IFD e, os resultados obtidos em ambos os Grupos, I e II, foram analisados estatisticamente pelo Índice kappa (k) visando a determinação do grau de concordância ou confiabilidade entre os dois métodos diagnósticos. No Grupo I, o diagnóstico de LED foi firmado em 100% (11/11) dos animais, pela reação de IFD, enquanto que o exame histopatológico estabeleceu o diagnóstico em 81,8% (9/11) dos casos. A positividade da IFD para o LED canino foi estabelecida, em sua totalidade, a partir da fluorescência esverdeada evidenciada na ZMB e/ou em seus anexos cutâneos e, os imunoreagentes mais frequentemente encontrados foram a IgM e C3. Já, em relação ao Grupo II, na totalidade dos animais não se evidenciou histopatologicamente qualquer alteração tegumentar.Também, pela IFD os resultados mostraram-se negativos. O substancial grau de concordância entre a IFD e a histopatologia (k= 0,738 e p= 0,002) comprova que a reação de imunofluorescência direta é exequível e útil no estabelecimento do diagnóstico do LED canino. / The discoid lupus erythematosus (DLE) is the most common variant of the Complex Lupus Erythematosus, considered one of auto-immune skin diseases more evident in dogs, getting very close to the casuistry of pemphigus foliaceus. The disease is relatively benign and without systemic involvement, clinically characterized by leukoderma and / or erythema associated with loss of the normal planum nasale \"cobblestone \" architecture and immunologically by deposition of autoantibodies (IgA, C3, IgM and IgG) at the basement membrane zone (BMZ). This study aims to correlate the clinical and histopathological findings with those of direct immunofluorescence (DIF), aiming to increase the accuracy of diagnosis DLE. We included 11 dogs (Group I) with cutaneous lesions characteristic of DLE and five dogs (Group II), with no cutaneous alterations, for the negative DIF. Cutaneous fragments derived from the planum nasale were submitted to histopathological examination and DIF, and the results obtained in both Groups I and II were analyzed by kappa index (k) in order to determine the degree of agreement or reliability among two methods. In Group I, the diagnostic DLE was established in 100 % (11/11) of animals, by the reaction of DIF, while the histopathological examination confirmed the diagnosis in 81.8 % (9/11) of cases. The positive DIF for DLE canine was established, in its totality, from the greenish fluorescence evident in the BMZ and / or on their skin annexes and the immunoreagents most frequently found were IgM and C3. Now, in relation to the Group II, all animals did not reveal any histopathological tegumentar changes. Also, by the DIF results were negative. The substantial degree of agreement between the DIF and histopathology (k = 0.738 and p = 0.002) shows that the direct immunofluorescence assay is feasible and useful in establishing the diagnosis of canine DLE.
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MMP-2 immunoreactive protein in breast carcinoma and neoplastic cervical lesions:mMP-2 is a new prognostic factor in breast carcinomaTalvensaari-Mattila, A. (Anne) 30 September 1999 (has links)
Abstract
Tumor invasion and metastasis are the major causes of treatment
failure or death for carcinoma patients. Matrix metalloproteinases
(MMPs) are zinc dependent endopeptidases implicated in tumor invasion
and metastasis. The expression of MMP-2 has been previously linked
to invasiveness of carcinoma cells. The MMP-2 immunoreactive protein
was studied here in squamous cell carcinoma of the utrine cervix
and in adenocarcinoma of the breast by using a specific monoclonal
antibody in immunohistochemical stainings. Immunoreactive protein
of latent MMP-2 was found to be an early event in neoplastic transformation
of the cervix in 60 patients. All cases of early stage cervical
carcinoma expressed the latent MMP-2 protein, suggesting that MMP-2
could be a prerequisite for invasive behavior. In early stage cervical
carcinoma the high score of MMP-2 expression seemed to be associated
with poor histological differentiation and lymph node metastases. The
intensitivity (score) of the immunoreaction was not, however, associated
with clinical behavior of this disease.
New predictive markers would be useful in selecting breast
carcinoma patients to different modalities of adjuvant therapy.
The MMP-2 protein has been found in breast carcinoma tumor cells
in immunohistochemical analyses. MMP-2 has been found to be expressed
in breast carcinoma in some preliminary studies, but there are no
reports so far that would show a correlation of MMP-2 to survival
in breast carcinoma. In the current study comprising 373 patients
the expression of MMP-2 protein was found immunohistochemically
in primary breast carcinomas. It is shown here for the first time
that immunoreactive protein of MMP-2 in primary breast carcinoma
is associated with a shortened relapse-free survival (RFS) or relative
overall survival (OS). MMP-2 correlated to the risk of failure during
the anti-estrogen adjuvant therapy in postmenopausal breast carcinoma
patients with axillary lymph node metastasis without a high tumor
burden. It was also found here that premenopausal patients with
a node positive breast carcinoma showing MMP-2 positivity relapsed
early after the primary operation. Young patients (< 40 years)
with MMP-2 positive tumors had a poor outcome when compared to other
node-positive premenopausal breast carcinoma patients. A patient
group with a high risk for an early relapse was identified from
node-positive, premenopausal breast carcinoma patients.
In conclusion, the present data show for the first time MMP-2
immunoreactive protein to be a prognostic factor in breast carcinoma,
indicating further studies to explore the value of this enzyme in
clinical decision making.
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Functional and Expression Analysis of a Novel Basement Membrane Degrader in Drosophila MelanogasterFields, Christopher J 01 July 2016 (has links)
The Srivastava Lab is focused on the identification and characterization of genes that play a role in basement membrane remodeling. Previously, we identified putative basement membrane degraders through a genetic screen. One such gene has been suggested to play a role in the maintenance of the stem cell niche in Drosophila melanogaster, but no other information about the role this gene plays in development or disease has been published. Here, data are presented from experiments utilizing Drosophila genetics and immunohistochemistry that provide important insights on the biological role of this gene.
Collagenase activity was up-regulated upon overexpression of this gene, confirming it as a basement membrane degrader. Additionally, RNA in-situ hybridization experiment results showed expression in the developing imaginal discs of the 3rd instar larva tissues. Overexpression and knockdown studies further demonstrated morphological defects in a number of tissues, including the wing and the eye, and are suggestive of apoptosis. Acridine orange staining confirmed that cell death occurred when the gene was overexpressed and a cleaved caspase antibody staining indicated that process to be caspase-mediated apoptosis.
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Interações macromoleculares na matriz extracelular. Uma abordagem bioquímica e filogenética / Macromolecular interactions in the extracellular matrix. A biochemical and phylogenetic approachSouza, Sandro José de 07 December 1993 (has links)
O estudo de macrointeraçães na matriz extracelular (ECM) foi abordado em três modelos; a interação colágeno/colagenase, a interação colágeno/fibronectina e finalmente, a evolução da família enzimática das metaloproteinases de matriz (MMP). As MMP se caracterizam por sua notável especificidade contra componentes da ECM. As colagenases intersticiais, os membros mais estudados, clivam os colágenos intersticiais em um único ponto da molécula produzindo dois fragmentos característicos. Usando a hipótese da hidropaticidade complementar, a qual estipula que peptídeos codificados por sequências nucleotídicas complementares podem interagir entre si, foi possível caracterizar a sequência SQNPVQP em colagenase de fibroblasto ou SSNPIQP em colagenase de neutrófilo como importantes na interação das respectivas enzimas com o colágeno nativo. O fato da fibronectina, outro componente da ECM, ligar-se no mesmo domínio do colágeno clivado pelas colagenases possibilitou a utilização da mesma abordagem acima (hidropaticidade complementar) no estudo da interação colágeno/fibronectina. Sendo assim, foi possível caracterizar a sequência TNEGVMY da fibronectina como importante na interação com o colágeno. Adjacente a este sítio na fibronectina, existe uma sequência (AAHEEIC) que é homóloga ao sítio de ligação ao zinco presente nas MMP. Isto originou a possibilidade de que zinco pudesse modular a interação colágeno/fibronectina. De fato, zinco aumentou especificamente a ligação entre colágeno e fibronectina. Finalmente, abordou-se alguns aspectos filogenéticos da família das MMP. Foi caracterizada uma relação filogenética entre o núcleo enzimático das MMP e o domínio correspondente tanto na protease de Serratia como na protease B de Erwinia chrysanthemi, membros da mesma família de metaloproteinases bacterianas. Sendo assim, a atividade catalítica das MMP pode ter sido herdada das metaloproteinases bacterianas, enquanto a especificidade ao substrato talvez se constitua em uma aquisição das MMP eucarióticas. / The study of extracellular matrix (ECM) macrointeractions was approached in three models: the collagen/collagenase interaction, the collagen/fibronectin interaction and the molecular evolution of the matrix metalloproteinase (MMP) family of enzymes. MMP is characterized by its remarkable specificity against ECM components. Interstitial collagenases, the best studied members, attack interstitial collagens at a unique site producing two fragments. Using the complementary hydropathy hypothesis that states that peptides encoded by complementary nucleotide sequence can interact one to another, it was possible to characterize the sequence SQNPVQP (in fibroblast collagenase) or SSNPIQP (in neutrophil collagenase) as important in the interaction of the respective enzymes with collagen. The fact that fibronectin, another ECM component, binds at the same domain on collagen that is cleaved by collagenases arose the possibility of using the same approach (complementary hydropathy) in the study of collagen/fibronectin interaction. It was possible to characterize the fibronectin sequence TNEGVMY as important in the interaction with collagen. Adjacent to this site, there is a sequence (AAHEEIC) that shows an homology to the zinc-binding site present in several MMP. Therefore, zinc could be a modulator the collagen/fibronectin interaction. Finnaly, some phylogenetic aspects of the MMP family were studied. It was characterized a phylogenetic relationship between the catalytic core of MMP and the corresponding domain in Serratia protease and protease B from E. chrysanthemi, members of the same family of bacterial metalloproteinases. The catalytic activity of MMP can have evolved from the bacterial metaloproteinases whereas the substrate specificity is an acquisition of eukaryotic MMP
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Efeitos do bloqueador do canal de cálcio (Verapamil) sobre fibroblastos dérmicos humanos. / Effects of calcium channel blocker (Verapamil) on human dermal fibroblasts.Boggio, Ricardo Frota 16 June 2008 (has links)
O excesso de tecido cicatricial (quelóides e cicatrizes hipertróficas) é um defeito do processo de cicatrização das feridas, caracterizado por um aumento na produção da matriz extracelular. Neste estudo, fibroblastos dérmicos humanos tratados com 50 <font face=\"symbol\">mM verapamil apresentaram discreta modificação na distribuição dos microfilamentos e alteraram sua morfologia de fusiformes para estrelados/arredondados. Estes efeitos poderiam estar associados a baixos níveis de cálcio citosólico. Esta hipótese foi confirmada através marcação de fibroblastos tratados com calcium green. Observamos também, que o verapamil inibiu a proliferação celular em 64,4%, aumentou a secreção de MMP1 e diminuiu o colágeno sintetizado pelos fibroblastos, sem aparentes efeitos citotóxicos. O metabolismo celular do cálcio está aparentemente relacionado a produção da matriz extracelular e portanto as patologias hipertróficas da cicatrização (quelóides e cicatrizes hipertróficas) podem responder ao tratamento com bloqueadores do canal de cálcio (verapamil). / Excessive scar tissue (keloids and hypertrophic scars) is a defective wound healing process characterized by overproduction of extracellular matrix. In the present study human dermal fibroblasts treated with 50 <font face=\"symbol\">mM verapamil changed their normal spindle-shaped morphology to stellate/rounded and showed discrete reorganization of microfilaments We hypothesized that these effects would be associated to lower levels of cytosolic Ca2+. Indeed, short time loading with calcium green confirmed that verapamil-treated fibroblasts exhibited lower intracellular calcium levels. We also observed that verapamil decrease cellular proliferation by 64.4%, increase the secretion of MMP1 and decrease synthesis of collagen in cultured fibroblasts. This alterations induced by verapamil are not associated with cytotoxic effects. The cellular calcium metabolism appears to regulate extracellular matrix production and so those hypertrophic disorders of wound healing (keloids and hypertrophic scars) may respond to therapy with calcium antagonist drugs (verapamil).
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