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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.
81

Polimorfismos dos genes MUC1 e Osteopontina em novilhas da raça Nelore (Bos taurus indicus) / Polymorphisms in MUC1 and osteopontin genes in Nelore heifers

Souza, Fabio Ricardo Pablos de 03 May 2007 (has links)
A MUC1 (MUC1) e a osteopontina (SPP1) são glicoproteínas expressas na superfície luminal uterina com funções na proteção e adesão celular. A MUC1 possui função antiadesiva, enquanto a osteopontina desempenha função adesiva. A expressão de ambas é regulada pelo hormônio esteróide progesterona. Durante a fase receptiva do útero, a MUC1 é inibida por este hormônio, enquanto a osteopontina é estimulada. O objetivo deste trabalho é caracterizar o polimorfismo genético destas moléculas e analisar a associação entre o polimorfismo, o diagnóstico de gestação e as diferenças esperadas na progênie (DEP) de várias características em novilhas da raça Nelore (Bos taurus indicus). A amostra foi constituída por 309 novilhas procedentes de duas fazendas participantes do Programa de Melhoramento Genético da Raça Nelore (PMGRN). A amostra da primeira fazenda incluiu 56 novilhas prenhas e foi utilizada para caracterização do polimorfismo e da estrutura do número variável de repetições em tandem (VNTR) MUC1 na raça Nelore. A segunda amostra foi constituída por 76 novilhas com resultado positivo de gestação e 156 com resultado negativo de gestação e foi utilizada para caracterização do polimorfismo dos genes MUC1 e SPP1 na raça Nelore, assim como para análise da associação entre os polimorfismos e os fenótipos. O gene MUC1 apresentou 5 alelos constituídos por um VNTR formado por uma seqüência de 60 nucleotídeos. A seqüência da repetição consensus foi idêntica às seqüências descritas em caprinos e em Bos taurus taurus. Descrevemos a seqüência de uma terceira repetição consensu na raça Nelore. O alelo 1 apresentou 10 repetições, o alelo 2 apresentou 12 repetições, o alelo 3 apresentou 15 repetições, o alelo 4 foi formado por 18 repetições, e o alelo 5 apresentou 24 repetições. O alelo com menor número de repetições apresentou a maior freqüência, sendo 0,70 na amostra do 1º grupo e 0,80 na amostra do 2º grupo. Os alelos 2, e 3 tiveram a segunda e terceira maior freqüência, sendo seguidos pelos alelos 4 e 5. A análise estatística não evidenciou associação entre o polimorfismo do gene MUC1 e o diagnóstico de gestação e entre o polimorfismo e os valores das diferenças esperadas na progênie das características consideradas economicamente importantes. Na amostra referente às novilhas da segunda fazenda, não identificamos o polimorfismo de nucleotídeo simples no íntron 4 (T/C) do gene SPP1 da osteopontina, como descrito na raça Holandesa. Sugerimos que a ausência deste polimorfismo possa constituir uma característica específica em Bos taurus indicus. Porém, dada a associação já descrita entre polimorfismo do gene SPP1 e características de crescimento, não descartamos a hipótese de que, assim como o MUC1, tenha ocorrido uma seleção indireta devido aos critérios aplicados pelo Programa de Melhoramento Genético da Raça Nelore. / MUC1 (MUC1) and osteopontin (SPP1) are glycoproteins expressed in the uterine luminal surface with predict functions in protection and cell adhesion. MUC1 has anti-adhesive role and osteopontin has adhesive role. The expression of both molecules is regulated by the steroid hormone, progesterone. During the receptive period for embryo implantation in the uterus, MUC1 is inhibited by progesterone and the osteopontin is stimulated. The objective of this work is to characterize the genetic polymorphism of these molecules, and to characterize associations between the polymorphisms, gestation rate and the expected progeny difference (EPD) in the Nelore breed (Bos taurus indicus). The study group comprised 309 heifers derived from two participating farms of the Nelore Cattle Breeding Program (PMGRN). The first farm provided 56 fertile female for the study for the characterization of the MUC1 polymorphism and the variable number of tandem repeats (VNTR) genomic structure in the Nelore breed. The second farm contributed 76 heifers with confirmed gestation and 156 no-pregnant female that were used to characterize both gene polymorphisms and to analyze the association between the MUC1 and SPP1 polymorphisms and the phenotypes. The MUC1 gene presented five alleles caused by length differences generated by a VNTR of 60 nucleotides. The consensus repeat sequence was identical to the caprine and Bos taurus taurus sequence. In this study we described the sequence of the third consensus repeat in the Nelore breed. Allele 1 presented with 10 repeats, allele 2 presented with 12 repeats, allele 3 presented with 15 repeats, allele 4 had 18 repeats and allele 5 had 24 repeats. Allele 1 had the smallest size and was the most frequent (0.70) in the group 1 and 0.80 in the group 2. Alleles 2 and 3 were the next most frequent followed by alleles 4 and 5. The ?2 test showed that the polymorphism was not significantly associated with the diagnostic of gestation and the EPD values. In this Nelore study group it was not possible to identify the single nucleotide polymorphism (T/C) of the SPP1 gene previously described in Holstein breed. The absence of this polymorphism could be specific to the Nelore cattle. However, considering the correlation between the SPP1 polymorphism and growth parameters, an indirect selection could happen due to the established criteria within the Nelore Cattle Breeding Program.
82

Correlação entre osteopontina sérica e polimorfismos nos genes GSTT1, GSTP1, ERCC1(118), XPD (751) com prognóstico e sobrevida em pacientes com carcinoma epidermóide de cabeça e pescoço / Relationship between plasma osteopontin and polymorphisms in the GSTT1, GSTP1, ERCC1 (118), XPD (751) genes with the prognosis and survival in patients with head and neck carcinoma

Brunialti, Karen Cristina de Sant'Anna 30 September 2009 (has links)
INTRODUÇÃO: A resposta ao tratamento no carcinoma epidermóide de cabeça e pescoço (CECCP) varia significantemente em diferentes casos e muitos pacientes não respondem ao tratamento e são expostos aos seus efeitos. A cisplatina é o quimioterápico mais utilizado no tratamento de CECCP e a quimioradioterapia é o método terapêutico usado nos carcinomas localmente avançado. Neste trabalho foram estudados possíveis marcadores de resposta a quimioradioterapia e sobrevida em pacientes portadores de CECCP, dentre eles a osteopontina (OPN) que tem sido associada à agressividade tumoral em vários cânceres e também tem sido relacionada a sobrevida, formam estudados também alguns polimorfismos em genes que estão relacionados com a cisplatina, seja na detoxificação deste fármaco, Glutationas S transferase (GSTP1, GSTT1 e GSTM1), seja no reparo dos danos causados no DNA pela via de excisão de nucleotídeos (XPD -751 e ERCC 118). CASUÍSTICA E MÉTODOS: Amostras de 69 pacientes localmente avançados submetidos à quimioterapia adjuvante ou exclusiva com cisplatina tiveram a sua OPN dosada pelo imunoensaio elisa em coletas realizadas antes e depois do término do tratamento. Para a análise dos polimorfismos, amostras de 95 pacientes localmente avançados tratados com quimioradioterapia com cisplatina exclusiva foram analisadas por PCR RFLP. RESULTADOS: Com relação à OPN, dos 69 pacientes estudados, a concentração da OPN antes do início da quimioradioterapia no grupo como um todo, foi de 102,5 ng/mL com uma mediana de 82,1 ng/mL. O correspondente valor da OPN após o tratamento n=46 foi de 104,0 ng/mL e mediana de 92,9 ng/mL. A OPN se mostrou mais elevada nos pacientes com maior tamanho tumoral, p=0,009 (ANOVA). Em análises correlacionado reposta ao tratamento e concentração de OPN, observamos que os pacientes que obtiveram resposta completa apresentaram menores níveis de OPN do que aqueles que não responderam ao tratamento. Quando realizamos uma análise multivariada notamos correlação entre baixa OPN antes do tratamento e uma melhor sobrevida global. Na análise dos polimorfismos (n=95), observamos que para os genes de reparo de DNA, XPD e ERCC, o genótipo mais freqüente foi C/T (n=43) e A/A (n=44), respectivamente. Para a GSTP1 a maior freqüência foi de A/G (47,4%) e para a GSTT1 e M1, vimos que a maioria dos pacientes, 83,2% mostrou ter GSTT1 funcional, enquanto 58,9% tiveram GSTM1 não funcional. Neste grupo de pacientes, não notamos nenhuma associação significante entre os genótipos dos pacientes e a resposta a quimioradioterapia, assim como não foi possível uma correlação entre a sobrevida global e os genótipos. CONCLUSÃO: Em síntese, a OPN após o término do tratamento pareceu estar associada com a resposta ao tratamento e com uma melhor sobrevida no grupo estudado e em relação aos polimorfismos, um aumento do número de amostras possa talvez mostrar alguma associação com resposta ao tratamento e a sobrevida global em pacientes com CECCP localmente avançados. / INTRODUCTION: The response to treatment in head and neck squamous cell carcinoma (HNSCC) varies significantly in different cases and many patients do not respond to treatment and are exposed collateral effects. Cisplatin is a chemotherapeutic used to treat HNSCC and chemoradioterapy is the major strategy used in locally advanced carcinomas. In this work, we studied potential markers for chemoradioterapy response and survival in HNSCC patients, such as osteopontin (OPN), which has been associated with tumor aggressiveness and survival. Furthermore, it was studied some genetic polymorphisms related to cisplatin detoxification (glutathione - S transferase, subtypes GSTP1, GSTT1 and GSTM1), as well genes involved in the repair of DNA damage by nucleotide excision (ERCC and XPD -751 - 118). METHODS: Plasmatic OPN levels, before and end of treatment, were measured in 69 patients with locally advanced tumors submitted to adjuvant chemotherapy with cisplatin only by ELISA. For polymorphism analysis, samples from 95 patients with locally advanced tumors treated with cisplatin alone were analyzed by PCR - RFLP. RESULTS: The OPN levels before the chemoradioterapy in the group (n=69) was 102.5 ng/mL with a median of 82.1 ng/mL. The corresponding value of OPN after treatment (n= 46) was 104.0 ng/mL and a median of 92.9 ng/mL. The OPN was higher in patients with larger tumor size, p = 0.009 (ANOVA). In tests correlated to treatment response and concentration of OPN, we observed that patients who achieved complete response had lower levels of OPN than those who did not respond to treatment. The multivariate analysis revealed that lower OPN levels before treatment significant a better overall survival. In the analysis of the polymorphisms (n = 95) the frequency of genotype for the DNA repair genes (XPD and ERCC), was C / T (n = 43) and A / A (n = 44), respectively. The most frequent genotype for GSTP1 was A/ G (47.4%), in 83.2% of the patients, the GSTT1 was functional, while in 58.9% of patients presented GSTM1 non-functional. In this group of patients, there was no any significant association between the genotypes and chemoradiotherapy response nor overall survival. CONCLUSION: In summary, plasmatic OPN levels after treatment cisplatin seemed to be associated with treatment response and better survival. However, larger sample size would be demonstrating some association with treatment response and overall survival in patients with locally advanced HNSCC.
83

Osteopontin and osteoclasts in rheumatoid arthritis and osteoarthritis

Luukkonen, J. (Jani) 29 October 2019 (has links)
Abstract Rheumatoid arthritis and osteoarthritis are two chronic joint diseases, which cause two of the largest socioeconomical burdens among all joint diseases according to the World Health Organization. Both diseases are associated with changes in bone structure and bone cell, especially osteoclast, function. The etiology or pathogenesis of these diseases are not completely understood. Traditionally, osteoarthritis is seen as a disease resulting from mechanical wear of cartilage and bone, and rheumatoid arthritis as an autoinflammatory disease of synovial tissue. However, also in osteoarthritis chronic inflammation is present in synovial tissue, and in rheumatoid arthritis large changes in bone structure are seen. The field of study focusing on this connection between inflammation and bone is called osteoimmunology and it can explain many features of these chronic diseases linking joint health to disturbances in bone homeostasis. Here, the study focused on the function of osteoclasts in normal and pathological environments, and on the factors that have an effect on bone resorption, with a special emphasis on the protein osteopontin. Samples of synovial fluid and serum from rheumatoid arthritis and osteoarthritis patients were analyzed for factors affecting osteoclasts, and in vitro cell cultures of human derived osteoclasts were used to analyze osteoclast function in normal and pathological environment. The phosphorylation of osteopontin was found to be increased in rheumatoid arthritis, along with multiple other inflammatory factors that also affect osteoclasts, such as IL-6, IL-8 and VEGF. Osteoclast cell cultures showed how the use of different patient samples significantly affected osteoclastogenesis, due to so-called inflammatory osteoclastogenesis. Additionally, we show that osteoclasts deposit osteopontin into the resorption lacunae during bone resorption. Based on the results, the inflammatory component present in both osteoarthritis and rheumatoid arthritis significantly affects osteoclast function, and its further study in the future may reveal new therapeutic possibilities. Especially the new discoveries of osteopontin’s role in normal osteoclast function and its changes seen between osteoarthritis and rheumatoid arthritis may prove to have therapeutic potential. / Tiivistelmä Nivelreuma ja nivelrikko ovat kroonisia nivelsairauksia, jotka Maailman terveysjärjestön (WHO) mukaan aiheuttavat eniten sosioekonomista haittaa. Molemmissa sairauksissa luiden rakenteessa ja luusolujen, erityisesti osteoklastien, toiminnassa tapahtuu muutoksia. Kummankaan taudin etiologiaa tai patogeneesiä ei täysin tunneta. Perinteisesti ajatellaan, että nivelrikko johtuu rusto- ja luukudoksen mekaanisesta kulumisesta ja nivelreuma nivelkalvon autoinflammatoorisesta tulehduksesta. Kuitenkin nivelrikossa nähdään myös selkeä nivelkalvon krooninen tulehdus ja nivelreumassa suuria luun rakenteen muutoksia. Tutkimusala, joka tutkii tulehduksen ja luun yhteyttä, on nimeltään osteoimmunologia. Tässä väitöskirjassa tutkitaan osteoklastien toimintaa ja niihin vaikuttavia tekijöitä, erityisesti proteiini osteopontiinia, normaalissa ja tautiympäristössä. Analysoin osteoklasteihin vaikuttavia tekijöitä nivelrikko- ja nivelreumapotilaiden näytteistä sekä osteoklastien toimintaa soluviljelmissä. Soluviljelmissä käytettiin nivelreuma- ja nivelrikkopotilaiden näytteitä mahdollisimman totuudenmukaisen ympäristön luomiseksi osteoklasteille. Tutkimuksessa osoitettiin, kuinka osteopontiinin fosforylaatio on lisääntynyt nivelreumapotilaiden nivelnesteessä. Myös useiden muiden osteoklasteihin vaikuttavien tekijöiden, kuten IL-6:n, IL-8:n ja VEGF:n, havaittiin lisääntyneen nivelreumassa. Osteoklastien soluviljelmissä havaittiin selkeät erot siinä, miten eri potilasnäytteet vaikuttavat osteoklasteihin ja erityisesti tulehduksen aiheuttamaan osteoklastien syntyyn. Osoitan myös, miten osteoklastit erittävät osteopontiinia luunhajotuskuoppaan luun hajotuksen aikana. Tutkimustulosten mukaan krooninen tulehdustila nivelrikossa ja nivelreumassa vaikuttaa huomattavasti osteoklastien toimintaan. Uskon, että lisätutkimukset tällä saralla voivat paljastaa uusia hoidollisia mahdollisuuksia. Erityisesti uudet löydökset osteopontiinin roolista osteoklastien toiminnassa sekä muutoksista nivelrikossa ja nivelreumassa vaativat jatkotutkimuksia, jotta proteiinin kliininen merkittävyys saadaan selvitettyä.
84

Étiopathogenèse de la scoliose idiopathique de l'adolescent : implication de la mélatonine et de l'ostéopontine

Azeddine, Bouziane 08 1900 (has links)
La scoliose idiopathique de l’adolescent (SIA) est une maladie dont la cause est encore inconnue, et qui génère des déformations complexes du rachis, du thorax et du bassin. La prévalence est de 4% dans la population adolescente au Québec. Cette pathologie affecte surtout les filles durant leur poussée de croissance pubertaire. Parmi plusieurs hypothèses émises, l’hypothèse neuroendocrinienne, impliquant une déficience en mélatonine comme agent étiologique de la SIA a suscité beaucoup d’intérêt. Cette hypothèse découle du fait que l’ablation de la glande pinéale chez le poulet produit une scoliose ressemblant sous plusieurs aspects à la pathologie humaine. La pertinence biologique de la mélatonine dans la scoliose est controversée, étant donné que la majorité des études chez l’homme n’ont pu mettre en évidence une diminution significative des niveaux de mélatonine circulante chez les patients scoliotiques. Nous avons démontré un dysfonctionnement dans la signalisation de la mélatonine au niveau des tissus musculo-squelettiques chez une série de patients atteints de SIA (Moreau & coll. 2004). Nous avons confirmé ce défaut chez un plus grand nombre de patients ainsi qu’en utilisant une nouvelle technologie (spectroscopie cellulaire diélectrique) n’ayant pas recours à un prétraitement des cellules donnant ainsi des résultats plus précis. Cette technique a montré la présence des mêmes groupes fonctionnels identifiés auparavant par la technique d’AMPc. Le dysfonctionnement de la signalisation de la mélatonine est dû à une phosphorylation accrue des protéines G inhibitrices. Ce défaut pourrait être causé par un déséquilibre de l’activité des kinases et phosphatases capables de réguler la phosphorylation des protéines Gi. Parmi ces kinases, PKCd a suscité initialement notre intérêt vu qu’elle peut phosphoryler les protéines Gi. Nous avons démontré que cette kinase interagit avec le récepteur de la mélatonine MT2 et que cette interaction varie selon le groupe fonctionnel auquel un patient SIA appartient. Par la suite nos travaux se sont dirigés vers la découverte d’effecteurs cellulaires régulés par la mélatonine et plus spécifiquement l’ostéopontine (OPN), compte tenu de son rôle présumé comme mécanorécepteur et dans certaines structures jouant un rôle dans la proprioception, le contrôle postural et la fonction vestibulaire. L’OPN a été identifiée initialement par sa surexpression au niveau protéique et de l’ARNm dans la musculature paraspinale uniquement chez les poulets scoliotiques. Nous avons également utilisé un autre modèle animal, la souris C57Bl/6 naturellement déficiente en mélatonine. Nous avons généré des souris bipèdes en amputant les membres antérieurs de souris OPN KO, des souris CD44 KO ainsi que des souris contrôles C57Bl/6. Nos résultats ont montré qu’aucune souris OPN KO (n=50) ou CD44 KO (n=60) ne développe la maladie, contrairement aux souris contrôles C57Bl/6 (n=50) dont 45% deviennent scoliotiques. Ces résultats nous ont poussés à investiguer le rôle de cette protéine dans l’étiopathogenèse de la maladie chez l’humain. Nos résultats ont montré une augmentation des niveaux circulants d’OPN chez les patients atteints de la SIA et que l’élevation en OPN corrélait avec la sévérité de la maladie. Nos études chez les enfants asymptomatiques nés de parents scoliotiques et qui sont plus à risque de développer la maladie ont aussi démontré des différences significatives au niveau des concentrations en OPN en comparaison avec les sujets sains. En effet, plusieurs enfants à risque présentaient des niveaux d’OPN supérieurs à 800ng/ml suggérant un plus grand risque de développer une scoliose indiquant aussi que l’augmentation des niveaux en OPN précède le début de la maladie. / Adolescent idiopathic scoliosis (AIS) is the most common form of scoliosis that affects a significant number of young teenagers, mainly females. Historically, several hypotheses were postulated to explain the aetiology of AIS. The neuroendocrine hypothesis involving a melatonin deficiency as the source for AIS has generated great interest. This hypothesis stems from the fact that experimental pinealectomy in chickens, and more recently in rats maintained in a bipedal mode, produces scoliosis. The biological relevance of melatonin in idiopathic scoliosis is controversial since no significant decrease in circulating melatonin level has been observed in a majority of studies. Analysis of melatonin signal transduction in musculoskeletal tissues of AIS patients demonstrated for the first time a defect occurring in a cell autonomous manner in different cell types isolated from AIS patients suffering of the most severe form of that disease. We confirmed this defect by analysing more AIS patients and by using a new technology (cellular dielectric spectroscopy) which gives more precise results because it allows the measurement and analysis of receptor activation without the need to pretreat cells. This technique showed the same functional classification into three functional groups as identified by cAMP technique. Melatonin signalling dysfunction is caused by phosphorylation of serine residues affecting the activity of G inhibitory (Gi) proteins normally associated with melatonin receptors present at the cell surface. This defect could be caused by an imbalance in the activity of kinases or phosphatases that can regulate Gi proteins phosphorylation. Among these kinases PKCd was initially of interest because it has been shown that it can phosphorylate Gi proteins. We showed that this kinase interacts with melatonin receptor MT2 and that this interaction varies from one functional group to another. Thereafter, we moved one step further to characterise downstream effector regulated by melatonin. This work has led to the identification of osteopontin (OPN) which is a relevant candidate because it can act as a mecanosensor and it is involved in proprioception, postural and vestibular control. OPN was initially identified in pinealectomized chickens where it was shown to be upregulated at protein and mRNA levels only in scoliotic ones. We also used another animal model, C57Bl/6 mice which are naturally deficient in melatonin. We generated bipedal mice by amputating forelimbs of OPN knock-out mice, CD44 knock-out mice as well as C57Bl/6 wild type mice. Our results showed that all bipedal mice OPN Knock-out or CD44 Knock-out did not develop scoliosis contrasting with C57Bl/6 wt mice where 45% develop scoliosis. These results prompted us to investigate the role of this protein in scoliosis etiopathogenesis in humans. We showed an increase in the OPN circulating levels in AIS patients and this elevation correlates with disease severity. Elevated plasma OPN levels were also found in the asymptomatic at-risk group (offspring of scoliotic patients), suggesting that these changes precede scoliosis onset.
85

The pro-inflammatory and calcification effects of DMP-1 on pulp fibroblasts. Implications for the prevention of dental pulp calcifc metamorphosis

Abd-Elmeguid, Ashraf A.E. Unknown Date
No description available.
86

Healing of endosseous implants with different surface characteristics in grafted and non-grafted bone : clinical and experimental studies

Jungner, Måns January 2014 (has links)
Aims: This study uses radiological and clinical evaluations of the healing of endosseous titanium implants presented with different surface characteristics in the clinical situation (paper I-III) and experimentally to describe the early bone healing in maxillary sinus membrane elevation with and without the use of grafting material (paper IV). Material and methods: In paper I, 136 patients were treated with 394 dental implants – 199 were oxidized titanium implants (Nobel Biocare TiUnite) and 195 were turned titanium surface implants (Nobel Biocare Mark III). Implant survival rates were retrospectively investigated after a minimum of five months after functional loading of the implants. At the five-year follow-up (paper II), eight patients were deceased and 128 were invited. Twenty-five patients refrained from participating in the study. The remaining 103 patients (287 implants – 133 with a turned surface and 154 with an oxidized surface) were examined after at least five years of functional loading. Clinical examinations of bleeding on probing (BoP) and pocket depth (PD) were performed. Intraoral radiographs were used to assess marginal bone levels (MBLs). In paper III, 28 patients were subjected to autologous bone graft and delayed implant placement, with a total of 92 dental implants. Thirteen patients received 47 implants with a turned surface and 15 patients received 45 implants with an oxidized surface. After a minimum of five years of functional loading, all patients were clinically examined regarding PD and BoP. The MBL was measured in intraoral radiographs. Cone beam computed tomography (CBCT) was used to evaluate the apical bone level (ABL) of the implants and intra-sinus conditions. The experimental study (paper IV) used nine adult male tufted capuchin primates (Cebus apella). Eight animals were subjected to bilateral maxillary sinus membrane elevation using a lateral replaceable bone window technique. One oxidized dental implant was placed in the residual bone of the sinus floor, protruding into the maxillary sinus cavity on both sides. In four animals, one sinus was left without any additional treatment, while the contralateral sinus was filled with autologous bone grafts from the tibia. In two animals, the implants were inserted under the elevated sinus membrane on both sides. In two animals, the sinus membrane was totally removed bilaterally before placement of implants. The animals were euthanized after 10 (n=4) or 45 (n=4) days. One non-operated animal representing pristine tissue conditions served as the control. The maxillary sinuses with implants were retrieved and further processed to prepare light microscopic ground sections or decalcified sections for immunohistochemical analyses. Results: In paper I seven implants were lost in five patients – six in the maxilla and one in the mandible. All failed implants were Mark III turned implants. The overall implant survival rate was 98.2% with a survival rate of 96.4% for implants with turned surface after a minimum of five months after functional loading. In paper II, one additional oxidized implant failed, giving an overall cumulative survival rate of 94.7 and 99.4%, respectively, after at least five years of functional loading. There was no difference for BoP, PD, or MBL between turned and oxidized implants. A total of two implants, three oxidized and one turned, showed a PD > 3 mm, MBL > 4 mm, and BoP. However, none of these were associated with suppurative infection on examination. In paper III no difference was found between the two implants surfaces used in terms of PD, BoP, MBL, or ABL. Pathological reactions to the sinus membrane were seen in four of the patients (14%). Radiographic signs of sinus pathology were not correlated to either survival rate of the implants or any of the investigated parameters. In the experimental paper IV, bone formation started from the bottom of the sinus floor, sprouting into the granulation tissue along the implant surface under the elevated membrane irrespective of time and surgical technique. Bone formation was not seen in direct conjunction with the sinus membrane. A distinct expression of osteopontin was observed in the serous glands of deeper portion of the lamina propria in direct connection with the elevated sinus membrane and close to the implant within all groups. Conclusion: After more than five years of function in non-grafted patients, oxidized implants had a survival rate higher than turned implants, although this was not statistically significant. No difference was found in MBL, PD, or BoP. Grafting of the maxillary sinus floor with intra- orally harvested bone and delayed placement of either turned or oxidized implants resulted in equally high long-term survival rates, MBL, ABL, and BoP. Pathological findings in the maxillary sinus cavity, in terms of sinus membrane health, are few and not correlated to any of the other investigated parameters. In the experimental study bone formation after sinus membrane elevation with or without additional bone grafts started at the sinus floor and sprouted into the elevated space along the implant surface. Removal of the membrane resulted in less bone formation. The sinus membrane did not seem to present osteoinductive potential in sinus membrane elevation procedures.
87

Expression of Non-Collagenous Proteins by the Epithelial Rest Cells of Malassez

Rincon, Julio C. Unknown Date (has links)
Epithelial rest cells of Malassez (ERM) are small groups of epithelial cells within the periodontal ligament closely approximated to the radicular cementum surface. The cells have a high nuclear/cytoplasm ratio. In oblique sections of the periodontal ligament, the cell rests can be seen, not as isolated groups of cells but as a network, similar to a fish-net, surrounding the root. The function of the ERM is unknown and their participation in some dental pathological conditions is still controversial. Some new publications have described the isolation of ERM from human periodontal ligaments. To date no publications have described the expression of bone-related proteins by ERM. ERM were cultured and isolated from porcine periodontal ligaments (chapter 2). An immunohistochemical study was carried out in rat porcine and human periodontal sections using AE1/AE3 antibody. The expression of cytokeratins by ERM was demonstrated in all species (chapter 3). Characterization and identification of ERM was achieved by Transmission Electron Microscopy (TEM), immunohistochemistry and Western blot. The results demonstrated the epithelial nature of these cells obtained from the mid radicular third of porcine first deciduous molars (chapter 4). An in vitro study using a semi quantitated RT-PCR technique was carried out in four different types of porcine periodontal cells (GF, PDLF, ERM and alveolar bone cells). These cell types were compared for the expression of the bone related proteins osteopontin and bone sialoprotein. The strongest expression of osteopontin was for the ERM compared to alveolar bone cells, PDLF and GF. These results demonstrated for the first time the expression of osteopontin from cultured porcine ERM suggesting a possible role of these cells in cementogenesis (chapter 5). Finally, emdogain (EMD), an enamel matrix derivative protein, was utilized at different concentrations to stimulate periodontal ligament cells and determine its role in proliferation, attachment and by RT-PCR expression of osteopontin or bone sialoprotein in vitro (chapter6). EMD demonstrated proliferative and attachment responses in a dose dependent manner. EMD stimulated the expression of OPN m RNA by porcine ERM and alveolar bone cells. The results contribute to explaining the different regenerative events associated with EMD in periodontal regenerative therapy. The findings of this study contribute to a broader understanding of possible functions of the ERM and suggests a role for these cells in cementogenesis by their strong OPN expression.
88

Determinação dos valores plasmáticos de osteopontina em cães com tumores mamários metastáticos ou não: correlações clínicas e anatomopatológicas

Garrido, Eduardo [UNESP] 28 February 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-28Bitstream added on 2014-06-13T20:17:36Z : No. of bitstreams: 1 garrido_e_me_jabo.pdf: 641792 bytes, checksum: 829824f36db4fb3b8f0eadf83a175018 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A osteopontina (OPN) é uma proteína produzida por diversas células e tem grande implicação com o desenvolvimento de tumores mamários e na disseminação de metástases em humanos. Em cães há poucos estudos envolvendo neoplasias e OPN. Neste trabalho objetiva-se determinar as concentrações de OPN sérica em cães sem a presença de tumores mamários (GC) ou com presença de carcinoma mamário ou carcinoma em tumor misto, com e sem metástase macro ou microscopicamente evidente. Utilizou-se o Ensaio Imunoenzimático Enzyme Linked Immunosorbent Assay (ELISA), a partir do plasma colhido antes e após a ressecção cirúrgica do tumor, em animais com neoplasia, e apenas em um momento (basal) nos animais sadios. As informações do ensaio, assim como os dados histopatológicos, hematológico e de bioquímica sérica foram confrontadas e analisadas por análise de variância e teste de Tukey. Os cães do GC obtiveram média de OPN de 2499 ± 1159 ng/d, com amplitude de referência entre 4770 e 227 ng/dL. Os cães com presença de tumor, quando em um único grande grupo, obtiveram uma diminuição significativa nos níveis plasmáticos de OPN, quando avaliado a densidade óptica. Quando o grupo se subdivide, em função do tipo histológico e/ ou presença de metástases, os resultados não evidenciam diferenças significativas nos níveis plasmáticos de OPN entre os animais sadios e os animais com neoplasias metastáticas ou não. A análise de correlação também não apresentou nenhum resultado significativo com os dados hematológicos ou de bioquímica sérica. Nas condições de realização deste ensaio, infere-se que, ao contrário... / The osteopontin (OPN) is a protein produced by several cells and has extensive involvement with the development of mammary tumors and its spread through metastases in humans. In dogs there are no studies involving cancer and OPN. This study aimed to determine serum concentrations of OPN in dogs without the presence of mammary tumors (GC) and presence of carcinoma in breast or carcinoma in mixed tumor with or without metastasis macro or microscopically evident. We used immunoenzymatic assay Enzyme Linked Immunosorbent Assay (ELISA) from plasma collected before and after surgical resection of the tumor, in animals with cancer, and only at a time (baseline) in healthy animals. The information of the test, and histopathological data, hematology and serum biochemistry were compared and analyzed by ANOVA and Tukey test. Dogs GC got an average of OPN in 2499 ± 1159 ng / d, with reference range between 227 and 4770 ng / dL. Dogs with the presence of tumor, when one large group, had a significant decrease in plasma levels of OPN, when determined by optical density. When the group is subdivided, according to the histological type and / or metastasis, the results showed no significant differences in serum levels of OPN between healthy animals and animals with metastases or not. The correlation analysis did not show any significant result with hematological or serum 4 biochemistry. We conclude that, contrarily to what is observed in humans, OPN does not appear important in the diagnosis or prognosis of breast neoplasm in dogs
89

Polimorfismos dos genes MUC1 e Osteopontina em novilhas da raça Nelore (Bos taurus indicus) / Polymorphisms in MUC1 and osteopontin genes in Nelore heifers

Fabio Ricardo Pablos de Souza 03 May 2007 (has links)
A MUC1 (MUC1) e a osteopontina (SPP1) são glicoproteínas expressas na superfície luminal uterina com funções na proteção e adesão celular. A MUC1 possui função antiadesiva, enquanto a osteopontina desempenha função adesiva. A expressão de ambas é regulada pelo hormônio esteróide progesterona. Durante a fase receptiva do útero, a MUC1 é inibida por este hormônio, enquanto a osteopontina é estimulada. O objetivo deste trabalho é caracterizar o polimorfismo genético destas moléculas e analisar a associação entre o polimorfismo, o diagnóstico de gestação e as diferenças esperadas na progênie (DEP) de várias características em novilhas da raça Nelore (Bos taurus indicus). A amostra foi constituída por 309 novilhas procedentes de duas fazendas participantes do Programa de Melhoramento Genético da Raça Nelore (PMGRN). A amostra da primeira fazenda incluiu 56 novilhas prenhas e foi utilizada para caracterização do polimorfismo e da estrutura do número variável de repetições em tandem (VNTR) MUC1 na raça Nelore. A segunda amostra foi constituída por 76 novilhas com resultado positivo de gestação e 156 com resultado negativo de gestação e foi utilizada para caracterização do polimorfismo dos genes MUC1 e SPP1 na raça Nelore, assim como para análise da associação entre os polimorfismos e os fenótipos. O gene MUC1 apresentou 5 alelos constituídos por um VNTR formado por uma seqüência de 60 nucleotídeos. A seqüência da repetição consensus foi idêntica às seqüências descritas em caprinos e em Bos taurus taurus. Descrevemos a seqüência de uma terceira repetição consensu na raça Nelore. O alelo 1 apresentou 10 repetições, o alelo 2 apresentou 12 repetições, o alelo 3 apresentou 15 repetições, o alelo 4 foi formado por 18 repetições, e o alelo 5 apresentou 24 repetições. O alelo com menor número de repetições apresentou a maior freqüência, sendo 0,70 na amostra do 1º grupo e 0,80 na amostra do 2º grupo. Os alelos 2, e 3 tiveram a segunda e terceira maior freqüência, sendo seguidos pelos alelos 4 e 5. A análise estatística não evidenciou associação entre o polimorfismo do gene MUC1 e o diagnóstico de gestação e entre o polimorfismo e os valores das diferenças esperadas na progênie das características consideradas economicamente importantes. Na amostra referente às novilhas da segunda fazenda, não identificamos o polimorfismo de nucleotídeo simples no íntron 4 (T/C) do gene SPP1 da osteopontina, como descrito na raça Holandesa. Sugerimos que a ausência deste polimorfismo possa constituir uma característica específica em Bos taurus indicus. Porém, dada a associação já descrita entre polimorfismo do gene SPP1 e características de crescimento, não descartamos a hipótese de que, assim como o MUC1, tenha ocorrido uma seleção indireta devido aos critérios aplicados pelo Programa de Melhoramento Genético da Raça Nelore. / MUC1 (MUC1) and osteopontin (SPP1) are glycoproteins expressed in the uterine luminal surface with predict functions in protection and cell adhesion. MUC1 has anti-adhesive role and osteopontin has adhesive role. The expression of both molecules is regulated by the steroid hormone, progesterone. During the receptive period for embryo implantation in the uterus, MUC1 is inhibited by progesterone and the osteopontin is stimulated. The objective of this work is to characterize the genetic polymorphism of these molecules, and to characterize associations between the polymorphisms, gestation rate and the expected progeny difference (EPD) in the Nelore breed (Bos taurus indicus). The study group comprised 309 heifers derived from two participating farms of the Nelore Cattle Breeding Program (PMGRN). The first farm provided 56 fertile female for the study for the characterization of the MUC1 polymorphism and the variable number of tandem repeats (VNTR) genomic structure in the Nelore breed. The second farm contributed 76 heifers with confirmed gestation and 156 no-pregnant female that were used to characterize both gene polymorphisms and to analyze the association between the MUC1 and SPP1 polymorphisms and the phenotypes. The MUC1 gene presented five alleles caused by length differences generated by a VNTR of 60 nucleotides. The consensus repeat sequence was identical to the caprine and Bos taurus taurus sequence. In this study we described the sequence of the third consensus repeat in the Nelore breed. Allele 1 presented with 10 repeats, allele 2 presented with 12 repeats, allele 3 presented with 15 repeats, allele 4 had 18 repeats and allele 5 had 24 repeats. Allele 1 had the smallest size and was the most frequent (0.70) in the group 1 and 0.80 in the group 2. Alleles 2 and 3 were the next most frequent followed by alleles 4 and 5. The ?2 test showed that the polymorphism was not significantly associated with the diagnostic of gestation and the EPD values. In this Nelore study group it was not possible to identify the single nucleotide polymorphism (T/C) of the SPP1 gene previously described in Holstein breed. The absence of this polymorphism could be specific to the Nelore cattle. However, considering the correlation between the SPP1 polymorphism and growth parameters, an indirect selection could happen due to the established criteria within the Nelore Cattle Breeding Program.
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Correlação entre osteopontina sérica e polimorfismos nos genes GSTT1, GSTP1, ERCC1(118), XPD (751) com prognóstico e sobrevida em pacientes com carcinoma epidermóide de cabeça e pescoço / Relationship between plasma osteopontin and polymorphisms in the GSTT1, GSTP1, ERCC1 (118), XPD (751) genes with the prognosis and survival in patients with head and neck carcinoma

Karen Cristina de Sant'Anna Brunialti 30 September 2009 (has links)
INTRODUÇÃO: A resposta ao tratamento no carcinoma epidermóide de cabeça e pescoço (CECCP) varia significantemente em diferentes casos e muitos pacientes não respondem ao tratamento e são expostos aos seus efeitos. A cisplatina é o quimioterápico mais utilizado no tratamento de CECCP e a quimioradioterapia é o método terapêutico usado nos carcinomas localmente avançado. Neste trabalho foram estudados possíveis marcadores de resposta a quimioradioterapia e sobrevida em pacientes portadores de CECCP, dentre eles a osteopontina (OPN) que tem sido associada à agressividade tumoral em vários cânceres e também tem sido relacionada a sobrevida, formam estudados também alguns polimorfismos em genes que estão relacionados com a cisplatina, seja na detoxificação deste fármaco, Glutationas S transferase (GSTP1, GSTT1 e GSTM1), seja no reparo dos danos causados no DNA pela via de excisão de nucleotídeos (XPD -751 e ERCC 118). CASUÍSTICA E MÉTODOS: Amostras de 69 pacientes localmente avançados submetidos à quimioterapia adjuvante ou exclusiva com cisplatina tiveram a sua OPN dosada pelo imunoensaio elisa em coletas realizadas antes e depois do término do tratamento. Para a análise dos polimorfismos, amostras de 95 pacientes localmente avançados tratados com quimioradioterapia com cisplatina exclusiva foram analisadas por PCR RFLP. RESULTADOS: Com relação à OPN, dos 69 pacientes estudados, a concentração da OPN antes do início da quimioradioterapia no grupo como um todo, foi de 102,5 ng/mL com uma mediana de 82,1 ng/mL. O correspondente valor da OPN após o tratamento n=46 foi de 104,0 ng/mL e mediana de 92,9 ng/mL. A OPN se mostrou mais elevada nos pacientes com maior tamanho tumoral, p=0,009 (ANOVA). Em análises correlacionado reposta ao tratamento e concentração de OPN, observamos que os pacientes que obtiveram resposta completa apresentaram menores níveis de OPN do que aqueles que não responderam ao tratamento. Quando realizamos uma análise multivariada notamos correlação entre baixa OPN antes do tratamento e uma melhor sobrevida global. Na análise dos polimorfismos (n=95), observamos que para os genes de reparo de DNA, XPD e ERCC, o genótipo mais freqüente foi C/T (n=43) e A/A (n=44), respectivamente. Para a GSTP1 a maior freqüência foi de A/G (47,4%) e para a GSTT1 e M1, vimos que a maioria dos pacientes, 83,2% mostrou ter GSTT1 funcional, enquanto 58,9% tiveram GSTM1 não funcional. Neste grupo de pacientes, não notamos nenhuma associação significante entre os genótipos dos pacientes e a resposta a quimioradioterapia, assim como não foi possível uma correlação entre a sobrevida global e os genótipos. CONCLUSÃO: Em síntese, a OPN após o término do tratamento pareceu estar associada com a resposta ao tratamento e com uma melhor sobrevida no grupo estudado e em relação aos polimorfismos, um aumento do número de amostras possa talvez mostrar alguma associação com resposta ao tratamento e a sobrevida global em pacientes com CECCP localmente avançados. / INTRODUCTION: The response to treatment in head and neck squamous cell carcinoma (HNSCC) varies significantly in different cases and many patients do not respond to treatment and are exposed collateral effects. Cisplatin is a chemotherapeutic used to treat HNSCC and chemoradioterapy is the major strategy used in locally advanced carcinomas. In this work, we studied potential markers for chemoradioterapy response and survival in HNSCC patients, such as osteopontin (OPN), which has been associated with tumor aggressiveness and survival. Furthermore, it was studied some genetic polymorphisms related to cisplatin detoxification (glutathione - S transferase, subtypes GSTP1, GSTT1 and GSTM1), as well genes involved in the repair of DNA damage by nucleotide excision (ERCC and XPD -751 - 118). METHODS: Plasmatic OPN levels, before and end of treatment, were measured in 69 patients with locally advanced tumors submitted to adjuvant chemotherapy with cisplatin only by ELISA. For polymorphism analysis, samples from 95 patients with locally advanced tumors treated with cisplatin alone were analyzed by PCR - RFLP. RESULTS: The OPN levels before the chemoradioterapy in the group (n=69) was 102.5 ng/mL with a median of 82.1 ng/mL. The corresponding value of OPN after treatment (n= 46) was 104.0 ng/mL and a median of 92.9 ng/mL. The OPN was higher in patients with larger tumor size, p = 0.009 (ANOVA). In tests correlated to treatment response and concentration of OPN, we observed that patients who achieved complete response had lower levels of OPN than those who did not respond to treatment. The multivariate analysis revealed that lower OPN levels before treatment significant a better overall survival. In the analysis of the polymorphisms (n = 95) the frequency of genotype for the DNA repair genes (XPD and ERCC), was C / T (n = 43) and A / A (n = 44), respectively. The most frequent genotype for GSTP1 was A/ G (47.4%), in 83.2% of the patients, the GSTT1 was functional, while in 58.9% of patients presented GSTM1 non-functional. In this group of patients, there was no any significant association between the genotypes and chemoradiotherapy response nor overall survival. CONCLUSION: In summary, plasmatic OPN levels after treatment cisplatin seemed to be associated with treatment response and better survival. However, larger sample size would be demonstrating some association with treatment response and overall survival in patients with locally advanced HNSCC.

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