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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Enzymatic degradation of bovine serum albumin nanoparticles for drug delivery

Singh, Harsh 06 1900 (has links)
Coacervation is a mild process for developing protein NPs. Bovine serum albumin (BSA) NPs formed via this technique were stabilized using poly-L-Lysine (PLL); short interfering ribonucleic acid (siRNA) was used as a model drug for encapsulation. Specific and non-specific degradation of these coated and uncoated BSA NPs were carried using matrix metalloproteinase-2 (MMP-2) and trypsin, respectively. The particles were characterized with atomic force microscopy, zeta-potential, and photon correlation spectroscopy measurements. There was a significant increase in the zeta potential of BSA NPs upon coating. Trypsin digested the uncoated and coated BSA NPs and resulted in higher BSA release from the particles. However, MMP-2 treatment did not result in higher release of BSA from coated NPs despite the cleavability of coated polymer by MMP-2. This study described a method for obtaining BSA NPs in a controllable size range. Such particles showed degradability in the presence of trypsin and could be promising for targeted drug delivery applications. / Chemical Engineering
12

Structure-function analysis of the prosegment and the cysteine-rich domain of the proprotein convertase PC5A its interaction with TIMP-2 /

Nour, Nadia. January 1900 (has links)
Thesis (Ph.D.). / Title from title page of PDF (viewed 2008/01/30). Written for the Dept. of Medicine, Division of Experimental Medicine. Includes bibliographical references.
13

The influences of matrix metalloproteinase-1 expression on glioblastoma pathology

Pullen, Nicholas Alexander, January 1900 (has links)
Thesis (Ph.D.)--Virginia Commonwealth University, 2010. / Prepared for: Dept. of Anatomy and Neurobiology. Title from title-page of electronic thesis. Bibliography: leaves 159-193.
14

Alteração nos níveis de metaloproteinases da matriz e quimiocinas no fluido gengival durante o movimento dentário ortodôntico / Levels of the matrix metalloproteinases and chemokines in the gingival crevicular fluid of teeth under orthodontic forces

Jonas Capelli Júnior 29 June 2007 (has links)
O objetivo do presente estudo foi avaliar os níveis das metaloproteinases da matriz MMP-9, MMP-3 e MMP-13, e das quimiocinas MCP-1, MIP-1β e RANTES, no fluido gengival de dentes sob força ortodôntica. Foram recrutados 14 pacientes (3 homens e 11 mulheres) que foram submetidos à movimentação ortodôntica dos caninos superiores. Amostras do fluido gengival foram coletadas com tiras de Periopaper em diferentes tempos. O volume do FG foi determinado com o uso do Periotron e os niveis das MMPs e das quimiocinas quantificados usando-se uma multianálise imunoenzimática com microesferas. Os resultados mostraram que existe um aumento significativo no volume do FG na área de pressão em quase todos os tempos analisados, quando comparados às áreas de tensão. Os níveis da MMP-9 foram muito superiores aos das MMP-13 e MMP-3. Na análise da evolução do tempo pode ser observada uma alteração significativa nos níveis da quantidade total de MMP-9, MMP-13 e MMP-3 e na concentração de MMP-13 e MMP-3 durante o período de movimentação dentária no lado de pressão. A elevação dos níveis de expressão destas MMPs 1 hora após a aplicação da força ortodôntica sugere que estas enzimas estejam envolvidas na remodelação periodontal induzida. As quimiocinas MCP-1, MIP-1β e RANTES foram detectadas no sulco gengival em todos os diferentes intervalos de tempo analisados, nas áreas de tensão e de pressão. Porém, diversas amostras estavam abaixo do nível de detecção do ensaio e, os níveis dessas quimiocinas no fluido gengival não parecem ser alterados pelas forças ortodônticas. / The goal of the present study was to evaluate the levels of the matrix metalloproteinases MMP-9, MMP-3 and MMP-13 and of the chemokines MCP-1, MIP-1β and RANTES in the gingival crevicular fluid of teeth under orthodontic forces. Fourteen subjects (3 males and 11 females) were enrolled and subjected to orthodontic tooth movement of their maxillary canines. Samples of gingival crevicular fluid were collected from both tension and pressure sides using Periopaper strips at different time points. The volume of GCF was determined using a Periotron and the levels of MMPs and chemokines quantified using a multiplex microbead immunoassay. The results demonstrated that the levels of MMP-9 were higher than the levels of MMP-13 and MMP-3. Statistically significant fluctuations during the orthodontic tooth movement could be detected for the total amount of MMP-9, MMP-13 and MMP-3 and for the concentration of MMP-13 and MMP-3 at the pressure side. The elevation in the levels of these MMPs, 1 hour after the application of the orthodontic force, suggests that these enzymes are involved in the induced periodontal remodeling. The chemokines MCP-1, MIP-1β and RANTES were detected in the GCF in both tension and pressure sides at different time points. However, several samples were below the level of detection of the assay and the levels of theses mediators in GCF did not seem to be altered by the orthodontic forces.
15

Alteração nos níveis de metaloproteinases da matriz e quimiocinas no fluido gengival durante o movimento dentário ortodôntico / Levels of the matrix metalloproteinases and chemokines in the gingival crevicular fluid of teeth under orthodontic forces

Jonas Capelli Júnior 29 June 2007 (has links)
O objetivo do presente estudo foi avaliar os níveis das metaloproteinases da matriz MMP-9, MMP-3 e MMP-13, e das quimiocinas MCP-1, MIP-1β e RANTES, no fluido gengival de dentes sob força ortodôntica. Foram recrutados 14 pacientes (3 homens e 11 mulheres) que foram submetidos à movimentação ortodôntica dos caninos superiores. Amostras do fluido gengival foram coletadas com tiras de Periopaper em diferentes tempos. O volume do FG foi determinado com o uso do Periotron e os niveis das MMPs e das quimiocinas quantificados usando-se uma multianálise imunoenzimática com microesferas. Os resultados mostraram que existe um aumento significativo no volume do FG na área de pressão em quase todos os tempos analisados, quando comparados às áreas de tensão. Os níveis da MMP-9 foram muito superiores aos das MMP-13 e MMP-3. Na análise da evolução do tempo pode ser observada uma alteração significativa nos níveis da quantidade total de MMP-9, MMP-13 e MMP-3 e na concentração de MMP-13 e MMP-3 durante o período de movimentação dentária no lado de pressão. A elevação dos níveis de expressão destas MMPs 1 hora após a aplicação da força ortodôntica sugere que estas enzimas estejam envolvidas na remodelação periodontal induzida. As quimiocinas MCP-1, MIP-1β e RANTES foram detectadas no sulco gengival em todos os diferentes intervalos de tempo analisados, nas áreas de tensão e de pressão. Porém, diversas amostras estavam abaixo do nível de detecção do ensaio e, os níveis dessas quimiocinas no fluido gengival não parecem ser alterados pelas forças ortodônticas. / The goal of the present study was to evaluate the levels of the matrix metalloproteinases MMP-9, MMP-3 and MMP-13 and of the chemokines MCP-1, MIP-1β and RANTES in the gingival crevicular fluid of teeth under orthodontic forces. Fourteen subjects (3 males and 11 females) were enrolled and subjected to orthodontic tooth movement of their maxillary canines. Samples of gingival crevicular fluid were collected from both tension and pressure sides using Periopaper strips at different time points. The volume of GCF was determined using a Periotron and the levels of MMPs and chemokines quantified using a multiplex microbead immunoassay. The results demonstrated that the levels of MMP-9 were higher than the levels of MMP-13 and MMP-3. Statistically significant fluctuations during the orthodontic tooth movement could be detected for the total amount of MMP-9, MMP-13 and MMP-3 and for the concentration of MMP-13 and MMP-3 at the pressure side. The elevation in the levels of these MMPs, 1 hour after the application of the orthodontic force, suggests that these enzymes are involved in the induced periodontal remodeling. The chemokines MCP-1, MIP-1β and RANTES were detected in the GCF in both tension and pressure sides at different time points. However, several samples were below the level of detection of the assay and the levels of theses mediators in GCF did not seem to be altered by the orthodontic forces.
16

Expressão do Reck, um inibidor de metaloproteinases de matriz, no desenvolvimento pos-natal e na regressão prostatica pos-castração / Expression of Reck, an inhibitor of matrix metalloproteinases, in the prostatic postnatal development and involution after castration

Peters, Helene 25 August 2005 (has links)
Orientador: Hernandes Faustino de Carvalho / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-05T10:11:12Z (GMT). No. of bitstreams: 1 Peters_Helene_M.pdf: 3147205 bytes, checksum: 29d84ddab25f17a17efc857545126663 (MD5) Previous issue date: 2005 / Resumo: A próstata tem merecido crescente atenção devido à maior incidência de câncer prostático e outras afecções do órgão, que resultam do aumento na longevidade dos indivíduos do sexo masculino em todo o mundo. Além disto, o desenvolvimento e crescimento prostático normal apresenta regulação androgênica e está sujeito a uma série de disruptores endócrinos que afetam o seu crescimento e função, assim como predispõem ao desenvolvimento tumoral. Nosso interesse reside principalmente na remodelação prostática seguida à castração e nas interações epitélio estroma que ocorrem neste órgão. Neste trabalho, investigamos a expressão do inibidor de metaloproteinases (MMPs) RECK, em nível de RNAm, procurando correlacioná-Io com o desenvolvimento pós-natal e com a regressão prostática seguida à castração. Para isto, foram utilizadas técnicas de RT-PCR semiquantitativo, Real time RT-PCR e de hibridação in situ,pareados sempre que possível com a expressão do RNAm e com a atividade de algumas MMPs. Os resultados demonstram que o gene RECK é expresso na próstata ventral de ratos, que existe uma significativa redução na sua expressão ao longo do desenvolvimento pós-natal, que há mecanismos diferenciados controlando a expressão dos pares RECKlMMP-2 e MMP-7/MMP-14. Foi observado também um crescente aCÚInulo da forma ativa da MMP-9, conforme o animal se aproxima da idade adulta. Utilizando RT-PCR semiquantitativo, pudemos determinar que o conteúdo relativo do RNAm para o RECK após a castração não muda, embora haja uma inversão no balanço entre a expressão epitelial (células epiteliais) e estromal (células musculares lisas e fibroblastos), nesta situação. No conjunto, os resultados sugerem que o RECK é expresso por diferentes tipos celulares da próstata ventral de ratos, com mecanismos de regulação complexos provavelmente oriundos da existência de diferentes compartimentos no órgão, ao contrário do que se observa para células isoladas / Abstract: The prostate has deserved increasingly attention due to the growing incidence of prostatic cancer and other prostatic diseases, which can be related to the longevity increase of men around the world. Besides, the normal prostatic development is under androgen regulation and as so is subject to a series of endocrine disruptors which affect its growth and function and predisposes to prostate cancer. Our interest resides on the prostatic remodelling following castration and on the epithelial-stromal relationships known to occur in the organ. In this work, we have investigated the expression of the matrix metalloproteinase inhibitor RECK, at the rnRNA leveI, trying to correlate its expression with the post natal prostatic development and regression after castration, using semiquantitative RT-PCR, Real time RT-PCR and in situ hybridization, paralleled with the determination of some MMPs expression and activity. Tbe results demonstrate that RECK is expressed in the rat ventral prostate, that there is a significative reduction in its expression during the post natal development, which is paralleled by the expression of some MMPs and that the mechanisms controling the pairs RECKJMMP-2 and MMP-7/MMP-14 are different. It was also observed an increased proportion of the active form of MMP-9, as the animal approaches adulthood. Using semiquantitative RT-PCR, we could determine that the relative content ofRECK rnRNA remains unchanged by castration, spite detecting an inversion in the balance between the epithelial (epithelial cells) and stromal (smooth muscle cells and fibroblasts) in this situation. Taken together, the results indicate that RECK is expressed by different cell types of the rat ventral prostate, with regulatory mechanisms appearing more complex, likely resulting ftom the existence of different compartments in the organ opposing what was seen for isolated cells / Mestrado / Biologia Celular / Mestre em Biologia Celular e Estrutural
17

Gelatinases, their tissue inhibitors and p53 in lymphomas

Kyllönen, H. (Heli) 26 May 2009 (has links)
Abstract Lymphomas are a heterogeneous group of malignancies, which usually have a good prognosis and high cure rates. Lymphomas are sensitive to chemotherapy and radiotherapy, and many patients can be cured even after a relapse, resulting in a need for effective follow-up. However, the cost-benefit ratio of radiological imaging in predicting the forthcoming relapses is poor. Consequently, there is a need for biological prognostic and predictive markers to distinguish patients at the highest risk of relapse at the time of diagnosis or during follow-up. Despite rapid progress in lymphoma treatments, some patients still die from lymphoma. Thus, more data on the basic biological features of lymphomas are also needed. Gelatinases (MMP-2 and MMP-9) and their tissue inhibitors (TIMP-1 and TIMP-2) have been found to play a role in the progression of solid tumours. TP53 is a tumour suppressor gene, the mutations and protein over-expression of which have been demonstrated to be associated with survival in most cancer types. There is also some evidence that these proteins could have prognostic significance in lymphomas as well. In the present study, the tissue expression, plasma concentrations and clinical value of gelatinases and their tissue inhibitors were evaluated in lymphomas. 249 primary tissue samples from patients with Hodgkin, follicular, or diffuse large B-cell lymphoma were analysed for expression of gelatinases and/or their inhibitors using immunohistochemistry. In follicular lymphoma, p53 protein expression was also investigated. The plasma samples of 126 lymphoma patients and a control group of 44 healthy volunteers were collected and studied by ELISA. TIMP-1 expression correlated with bulky tumour and nodular sclerosis subtype of Hodgkin lymphoma. In follicular lymphoma, p53 over-expression was an independent adverse prognostic factor for survival and a predictor of histological transformation. Plasma MMP-2-TIMP-2 complex appeared to be a potential follow-up marker predicting the risk of relapse in lymphoma patients. Plasma levels of the MMP-2-TIMP-2 complex, proMMP-2, TIMP-2 and proMMP-2/TIMP-2 ratio were at abnormal levels both in patients with newly diagnosed lymphoma and those in remission compared to healthy controls. The clinical significance of these markers needs further studies.
18

MOLECULAR CLONING AND PROTEIN BIOSYNTHESIS OF MATRIX METALLOPROTEINASE-7

Jack, Colin C. 06 May 2015 (has links)
No description available.
19

A NOVEL TREATMENT FOR DIABETIC FOOT ULCERS

Gabriele, Simona January 2018 (has links)
Tetracycline molecules including doxycycline (DOX), consist of a group of broad-spectrum antibiotics. In addition, tetracyclines inhibit matrix metalloproteinase (MMPs) that contribute to tissue remodeling, inflammation, angiogenesis and are over-expressed in certain pathologies - such as Alzheimer’s disease, metastasis and diabetic foot ulcers (DFUs). Tetracyclines are hypothesized to inhibit MMPs through the chelation and sequestration of catalytic divalent ions such zinc and calcium. This inhibitory duality may be beneficial in pathologies that are characterized by MMP over-expression and prone to infection, such as DFUs. Compared to oral administration, topical DOX is an attractive route of administration for chronic wound healing as it may minimize the risks: associated antibiotic resistance; is being targeted directly to the wound bed. However, DOX is notoriously unstable in aqueous solution and common topical formulations. Liquid chromatography and mass spectrometry (LCMS) were employed to monitor stability using an in vitro MMP assay and an applicable E. coli anti-bacterial assay was assessed to quantify drug activity. 2 % (w/w) topical DOX demonstrated an acceptable stability 30 day when stored at 4 ºC. DOX inhibited MMP9 activity with an IC50 value of 48.27 μM. With respect to anti-bacterial activity, using cultured BL21 E.Coli and quantification of drug activity as an expression of colony forming units (CFUs) successfully reproduced the antimicrobial IC50 of doxycycline as 4.3 µM. Transdermal DOX has the potential to improve standard of care for DFUs, quality of life for the patient and reduce costs to the healthcare system. / Thesis / Master of Science (MSc) / Tetracyclines comprise of a group of broad-spectrum antibiotics; whose primary mechanism of action is inhibition of protein synthesis through binding of the bacterial ribosome. In addition, tetracyclines inhibit matrix metalloprotease (MMPs), zinc-dependent proteases that contribute to tissue remodeling, angiogenesis and are over-expressed in certain pathophysiologies such as diabetic foot ulcers (DFUs). The antibacterial mechanism of DOX on MMPs is reported and understood, however the inhibition is hypothesized to involve cation chelation. Thus, investigating this interaction is warranted to assist in developing a therapeutic for DFUs. A more logical product would involve direct topical application, such as a stable transdermal formulation of DOX.
20

Evaluation of cerebrospinal fluid biomarkers of endothelial damage and basement membrane degradation as indirect indicators of blood-brain barrier dysfunction in chronic canine hypothyroidism

Pancotto, Theresa E. 16 May 2011 (has links)
A variety of neurologic illnesses including peripheral and cranial neuropathies, central vestibular disease, seizures and coma have been associated with hypothyroidism in dogs. Repeated studies have shown that there is loss of blood brain barrier (BBB) integrity in these animals. Current research has also shown the development cerebrospinal fluid abnormalities in neurologically normal hypothyroid dogs; a finding that is related to BBB degradation. This derangement may be secondary to atherosclerosis and vascular accidents. One possible mediator of vasospasm and ischemic brain injury is endothelin-1 (ET-1). Another group of mediators of vascular dysfunction that has been found in CSF of dogs with various other CNS diseases is matrix metalloproteinases (MMP). The purpose of this study was to assay molecular markers that may contribute to disruption in the blood brain barrier in chronically hypothyroid canines. We hypothesized that BBB disruption in hypothyroidism is mediated by ET-1 and MMPs, as evidenced by increased concentrations of these proteins in CSF compared to controls. Cerebrospinal fluid (CSF) previously collected from 9 control and 9 experimentally induced hypothyroid dogs was used. Administration of I-131 was used to create the experimental model. CSF from time points 0, 6, 12, and 18 months post-induction were evaluated using an ELISA kit for endothelin-1. CSF from each time point was also evaluated using gelatinase zymography to detect MMP-2,9, and 14. The endothelin assay was able to detect ET-1 in CSF as determined by a spike and recovery method. However, ET-1 was undetectable in CSF of control and hypothyroid dogs at all time points. Constitutively expressed MMP-2 was detectable in all dogs at all time points. No other MMPs were detectable in CSF. ET-1 and gelatinase MMP,-9, and -14 are not primary mediators of BBB damage in chronically hypothyroid dogs. They could be involved secondarily and may be better evaluated with different assays or in temporal association with the development of clinical signs of neurologic dysfunction. Additional research is needed to confirm this finding and to evaluate biomarkers of non-vascular components of the BBB. / Master of Science

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