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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.
1

PARÂMETROS Clínicos e Parasitológicos de Ovinos Mantidos em Confinamento Infectados Experimentalmente Com Larvas de Haemonchus Sp.

HUPP, B. N. L. 03 April 2014 (has links)
Made available in DSpace on 2018-08-01T22:56:54Z (GMT). No. of bitstreams: 1 tese_7714_dissertação bárbara lemos hupp.pdf: 784406 bytes, checksum: 98f7b46a207734035c47feb463514b4a (MD5) Previous issue date: 2014-04-03 / O objetivo deste trabalho foi estabelecer parâmetros parasitológicos que determinem a carga parasitária para intervenção anti-helmíntica, por meio de acompanhamento do comportamento parasitológico de grupos de ovinos mestiços Santa Inês infectados experimentalmente e não infectados (controle) com larvas de Haemonchus sp., mantidos sob sistema de confinamento total. O experimento foi conduzido no período de junho a agosto de 2013. Foram utilizados 14 ovinos machos inteiros, com peso corporal semelhante, livres de nematoides, que foram divididos em dois grupos com 7 animais cada. Posteriormente realizou-se a infecção experimental de um dos grupos com 10.000 larvas de Haemonchus sp., tendo com base os valores e recomendações estabelecidos pela World Association for the Advancement of Veterinary Parasitology (W.A.A.V.P.). As avaliações dos parâmetros (Ovos por grama de fezes, Famacha©, peso, proteínas plasmáticas totais e hematócrito) foram semanais, sendo a primeira iniciada 21 dias após a infecção, sendo, portanto os momentos de análise os dias zero (dia infecção) e 21, 28, 35, 42, 49, 56, 63 e 70. Ao término do período experimental, os animais foram abatidos e o trato gastrointestinal coletado para contagem e identificação dos parasitos adultos. Para o parâmetro OPG houve diferença significativa entre os grupos infectado e controle a partir do dia zero para todos os demais momentos analisados. No grupo infectado houve diferença significativa do dia zero para os demais, do dia 21 para os dias 28, 35 e 42 e do dia 35 e 42 para os dias 63 e 70. O hematócrito apresentou diferença significativa entre os grupos nos dias 21, 28, 35, 42, 49 e 63, e entre o dia zero e os dias 28, 35, 42, 56, 63 e 70 no grupo infectado. Para a variável Famacha ambos os grupos se mantiveram classificados como graus 1 e 2, ou seja sem sinais clínicos de anemia. As proteínas plasmáticas não apresentaram alterações entre os momentos ou entre os grupos durante todo o período experimental. Para variável peso também não foram constatadas diferenças entre os grupos em nenhum momento analisado. Os animais do grupo controle não apresentaram diferenças estatisticamente significativas entre os momentos durante todo o período experimental para todas as variáveis analisadas. A correlação entre OPG e número de parasitos adultos foi considerada forte (r = 0,93). A infecção experimental com 10.000 larvas de Haemonchus sp. não foi suficiente para alterar o estado de saúde geral dos animais nas condições estudadas e, portanto animais com OPG até 2500 não necessitam de intervenção anti-helmíntica quando em condições semelhantes as do presente trabalho.
2

Design panoramatického zubního rentgenu / Design of Panoramic Dental X-ray Machine

Juráňová, Zuzana January 2016 (has links)
The topic of this thesis is design of a panoramic X-ray. The main contribution is a new view on ergonomics of operator and a possibility of seating for patient. The aim is to create a device with innovative seating incorporated into the supporting leg of the machine, and to improve an ergonomics of machine manipulation. But it is also necessary to maintain all the technical, ergonomic, aesthetic and environmental requirements. The final draft should be able compete with existing products on the market.
3

Parasitos de import?ncia para a caprinocultura e a ovinocultura potiguar

Macedo, Mariany Patricia Wanderley de 24 March 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-04-25T23:51:26Z No. of bitstreams: 1 MarianyPatriciaWanderleyDeMacedo_DISSERT.pdf: 1476311 bytes, checksum: d40929188702a06876c5f930bd5a5f9e (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-04-28T20:01:08Z (GMT) No. of bitstreams: 1 MarianyPatriciaWanderleyDeMacedo_DISSERT.pdf: 1476311 bytes, checksum: d40929188702a06876c5f930bd5a5f9e (MD5) / Made available in DSpace on 2016-04-28T20:01:08Z (GMT). No. of bitstreams: 1 MarianyPatriciaWanderleyDeMacedo_DISSERT.pdf: 1476311 bytes, checksum: d40929188702a06876c5f930bd5a5f9e (MD5) Previous issue date: 2015-03-24 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A caprinocultura e a ovinocultura mostram-se como atividades agropecu?rias de grande import?ncia para o semi?rido nordestino. No entanto, a produ??o de caprinos e ovinos se faz com v?rias dificuldades. Dentre elas as infec??es parasit?rias, em especial as helmintoses do trato gastrintestinal, a eimeriose e a toxoplasmose; esta relacionada com problemas na reprodu??o. Em virtude disso, este trabalho teve como objetivo fazer o levantamento da ocorr?ncia e de alguns determinantes das parasitoses que acometem os rebanhos de pequenos ruminantes das microrregi?es Natal, Maca?ba, Litoral Sul, Angicos, Vale do A?u e Borborema Potiguar. Para isso foram aplicados instrumentos epidemiol?gicos com produtores, tratadores ou respons?veis pelos rebanhos e tamb?m realizadas colheitas de amostras de sangue e fezes dos animais em oito propriedades, localizadas em sete munic?pios dessas microrregi?es. A carga parasit?ria dos animais foi determinada atrav?s da contagem de ovos e oocistos por grama de fezes OPG e OoPG, respectivamente. Al?m disso, foi feita a recupera??o de larvas infectantes. Com as amostras de sangue foram feitas a mensura??o do volume globular e a pesquisa de IgG anti-Toxoplasma gondiino soro sangu?neo dos ovinos, por meio do teste imunoenzim?tico (ELISA). Para as vari?veis discretas, a an?lise estat?sticafoi feita por regress?o de Poisson, com n?vel de signific?ncia menor que 0,05.A an?lise dos instrumentos epidemiol?gicos permitiu observar que a ivermectina ? o antihelm?ntico utilizado em 85,71% das propriedades. Do total de amostras de fezes dos ovinos (n=179) 53,07% apresentaram positividade para ovos de helminto e 48,04% mostraram-se positivas para oocistos de Eimeria. Das amostras de fezes dos caprinos (n=133), 72,18% foram positivas para ovos de helmintos e 96,99% para oocistos de Eimeria. A menor contagem de OPG e de OoPG foi observada na microrregi?o Angicos. A maior contagem de OPG foi encontrada na microrregi?o Litoral Sul e a de OoPG na microrregi?o Borborema Potiguar.Para ambos os casos, a diferen?a foi estatisticamente significante (p?0,000). O g?nero de helminto mais prevalente foi Haemonchus, presente em 49,87% dos ovinos e em 80,42% dos caprinos. A m?dia do hemat?crito variou de 22,91 a 33,25 nos ovinos e de 22,62 a 28,25 nos caprinos. A preval?ncia de IgG anti-Toxoplasma gondii variou de 63,33% a 100,00%. Os caprinos mostraram-se mais suscept?veis ?s infec??es por parasitos do trato gastrintestinal do que os ovinos. Em todas as propriedades foi observada elevada preval?ncia de infec??o por T. gondii, sendo as menores porcentagens registradas nas microrregi?es Angicos e Borborema Potiguar. / The goat and sheep industry shows up as an agricultural activity of great importance for the semiarid Northeast. However, the sheep and goats production is made with various difficulties. Among them, parasitic infections, particularly helminth infections of the gastrointestinal tract, the eimeriosis and toxoplasmosis; this one related to problems in reproduction. For this reason, the aim of this study is to to make a survey of the occurrence and some determinants of parasitic diseases that affect small ruminant flocks of the microregions Natal, Maca?ba, Litoral Sul, Angicos, Vale do A?u and Borborema Potiguar. Thereunto, epidemiological tools were applied with producers, keepers or guardians of herds and also held collections of blood and feces of animals in eight properties located in seven municipalities of these microregions. The parasite load of the animals was determined through eggs and oocysts counting per gram of feces EPG and OPG, respectively. In addition, the recovery of infective larvae was made. Blood samples were used to measure the globular cell volume and the search for anti-Toxoplasma gondii IgG in sheep serum, by Enzyme Linked Immune Sorbent Assay (ELISA). For categorical variables, the statistical analysis was performed using Poisson regression, with significance level of 0.05. The analysis of the instruments showed that ivermectin is the anthelmintic used in 85,71% of properties. From the total of feces samples of the sheep (n = 179), 53,07% were positive for helminth eggs and 48,04% were positive for oocysts of Eimeria. From the samples of faeces of goats (n = 133), 72,18% were positive for helminth eggs and 96,99% for oocysts of Eimeria. The lowest EPG and OPG count was observed in the micro region of Angicos. Most of the EPG count was found in the micro region Litoral Sul and the OPG count in the micro-region Borborema Potiguar. Both cases the difference was statistically significant(p- value?0,000)The most prevalent helminth genus found was Haemonchus, present in 49,87% of the sheep and 80,42% of goats. The average of hematocrit ranged from 22,91 to 33,25 in sheep and from 22,62 to 28,25 in goats. The prevalence of anti-Toxoplasma gondii IgG ranged from 63,33% to 100,00%. The goats showed to be more susceptible to infections by parasites of the gastrointestinal tract than the sheep. In all the properties was observed high prevalence of infection by T. gondii, with the lowest percentages recorded in the micro regions Angicos and Borborema Potiguar.
4

Caracterização fenotípica e resposta imune de caprinos naturalmente infectados por nematoides gastrintestinais / Phenotypic characterization and immune response of goat crossbreds naturally infected by gastrointestinal nematode

Neves, Maria Rosalba Moreira das January 2014 (has links)
NEVES, Maria Rosalba Moreira das. Caracterização fenotípica e resposta imune de caprinos naturalmente infectados por nematoides gastrintestinais. 2014. 79 f. Tese (doutorado em zootecnia)- Universidade Federal do Ceará, Fortaleza-CE, 2014. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-04-22T17:32:51Z No. of bitstreams: 1 2014_tese_mrmneves.pdf: 1424697 bytes, checksum: 48849ed684234f036cd33f0ce794f96c (MD5) / Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-05-27T17:45:15Z (GMT) No. of bitstreams: 1 2014_tese_mrmneves.pdf: 1424697 bytes, checksum: 48849ed684234f036cd33f0ce794f96c (MD5) / Made available in DSpace on 2016-05-27T17:45:15Z (GMT). No. of bitstreams: 1 2014_tese_mrmneves.pdf: 1424697 bytes, checksum: 48849ed684234f036cd33f0ce794f96c (MD5) Previous issue date: 2014 / The aim of this study was to evaluate phenotypic, histologic, immunologic and molecular tools to characterize goat crossbred in resistant and susceptibily to gastrointestinal nematodes. For this purpose, we used 231 F2 animals of both genders, of ages between five and ten months, from four different kidding seasons. Stool and blood samples were collected weekly for eggs per gram of feces (EPG) determinations, fecal culture, packed cell volume (PCV), total plasma protein (TPP), blood eosinophils (EOS) and immunological tests. Famacha scores were obtained on the same sample collection days. The animals were ranked according to EPG values and the 12 animals with lowest means were considered resistant while the 12 animals with the highest means were considered susceptible. The animals in the experimental lot 4, presented the best phenotypic characterization and were chosen for, recovery of gastrointestinal nematodes and tissue samples for histological and gene expression determinations. EPG, PCV and TPP were effective in the identification of resistant and susceptible. In the other lots, the PCV, TPP, eosinophil count and Famacha were not as effective as EPG. IgG and IgA levels, particularly for Haemonchus contortus infection in both challenges, showed significant differences in some of the studied timepoints. Resistant animals presented higher eosinophil counts in the abomasum, indicating that these cells participate in the control of gastrointestinal infections. IL-5 and IL-10 gene expression levels were significantly higher in the susceptible group, showing that the expression of these cytokines in the fifth week of infection may have a role in mechanisms of susceptibility to gastrointestinal nematodes. / O objetivo deste estudo foi avaliar ferramentas fenotípicas, histológicas, imunológicas e moleculares para caracterizar caprinos mestiços quanto à resistência e susceptibilidade aos nematoides gastrintestinais. Para isso, foram utilizados 231 animais F2, de ambos os sexos, com idade variando de cinco a dez meses, provenientes de quatro lotes experimentais. Semanalmente, foram coletadas amostras de fezes e sangue para realização dos exames: contagem de ovos por grama de fezes (OPG), coprocultura, volume globular (VG), proteína plasmática total (PPT), eosinófilos sanguíneos (EOS) e determinação dos níveis de imunoglobulinas. Nos mesmos dias das coletas, também foi realizado o método Famacha. Os animais foram ordenados de acordo com os valores de OPG, os 12 animais que apresentaram as menores médias foram caracterizados como resistentes e os 12 animais que apresentaram as maiores médias foram caracterizados como susceptíveis. Os animais do lote experimental 4, como apresentaram a melhor caracterização fenotípica, foram necropsiados para a recuperação dos nematoides gastrintestinais e amostras de tecidos para análises histológicas e de expressão gênica. O OPG foi eficaz, nos quatro lotes, para a caracterização de caprinos resistentes e susceptíveis as parasitoses gastrintestinais nos dois desafios de infecção (P<0,05). No quarto lote, as variáveis: OPG, VG e PPT foram eficazes na identificação dos animais quanto a diferentes níveis de resistência. Nos demais lotes, o VG, a PPT, a contagem de eosinófilos e o Famacha não foram tão eficazes como o OPG, para diferenciar caprinos resistentes e susceptíveis às parasitoses gastrintestinais. Os níveis de IgA e IgG, em especial para Haemonchus contortus, nos dois desafios de infecção, e a contagem de eosinófilos no abomaso foram parâmetros eficazes na resposta imune, indicando que essas células de defesa apresentam um papel efetor no controle das infecções gastrintestinais. Na expressão gênica, a IL-5 e IL-10 apresentaram níveis superiores significativos no grupo susceptível, mostrando que a expressão destas citocinas na quinta semana de infecção pode ter papel em mecanismos de susceptibilidade a nematoides gastrintestinais.
5

Survey of parasitoses in beef cattle from two geographical areas of the Czech Republic / Survey of parasitoses in beef cattle from two geographical areas of the Czech Republic

Kubelka, Lukáš January 2016 (has links)
Research in this diploma thesis was focused on monitoring of the beef cattle parasites and periodically was done from April 2015 to November 2015 on three different farms in two different regions (Vysočina and Středočeský region) in the Czech Republic. 20 samples of fresh faeces were collected every month from each farm during morning. Processing and consequent evaluation of samples took place in parasitology laboratory at State Veterinary Institute in Jihlava. Samples were evaluated using a relatively new coprological technique FLOTAC, developed in Italy and recommended for parasitological qualitative and quantitative analysis of large farm animal eggs and oocysts. For each farm two pooled samples (10 g each) by subtracting 1 g of faeces from individual samples were used. Results were evaluated and statistically analysed by statistical software Statistica 13. There was occurrence of eggs of gastrointestinal nematodes (family Trichostrongylidae), tapeworms (Moniezia spp.) and oocysts of coccidia (Eimeria spp.) on all of the farms. Only on the farm 3 there was also occurrence of fluke eggs (Paramphistomum spp.). From the results it was evident, that farms that administered anthelmintic to livestock had significantly lower amounts of EPG/OPG in animal faeces. Despite of using pooled samples, method proved to be reliable and sensitive for monitoring of developing stages of livestock parasites. Even low amount of eggs or oocysts in animal faeces were detected by coprological technique FLOTAC.
6

Heat shock proteins : interactions with bone and immune cells

Davies, Emma Louise January 2004 (has links)
Heat shock proteins (Hsps) are increasingly being seen as having roles other than those of intracellular molecular chaperones, particularly with regard to their potential to act as cytokines, and to stimulate the innate immune system. Hsps have also been found to promote bone resorption and osteoclast formation in vitro, although the mechanism has not been previously identified. The overall aims of this thesis were to determine whether Hsps could stimulate bone resorption by affecting the RANKL/OPG pathway, and to address the hypothesis that Hsps can act as a danger signal to the innate immune system. In order for Hsps to affect either the RANKL/OPG system of bone resorption or act as danger signals they would need to be actively released from cells, ideally in a controlled manner following exposure to the source of stress. Hsp60 and Hsp70 were found to be released from a range of immune cells including the cell lines Jurkat and U937, and also PBMCs, T-cells and B-cells. This release was not due to cell damage. The release of Hsp60 and Hsp70 were downregulated by inhibitors of protein secretion, in particular Hsp70 release was reduced by compounds that inhibited lysosomal pathways and Hsp60 release by classical secretion inhibitors. Hsp60, Hsp70, GroEL and LPS all affected the RANKL/OPG system of bone regulation; OPG production and release was down-regulated in the MG63 and GCT osteoblast-like cell lines following treatment with Hsp60, Hsp70 and LPS, and RANKL expression was upregulated following treatment with Hsp60, Hsp70, GroEL and LPS. This effect on the RANKL/OPG system was found to translate into an effect on osteoclast formation when conditioned media from treated osteoblasts was added to osteoclast precursors in the presence of M-CSF. A range of different factors that affected Hsp release were identified; PHA activation of PBMCs was found to upregulate Hsp60 release from PBMCs. GroEL and LPS caused an upregulation in Hsp70 release from PBMCs and GCT osteoblast like cells, and Hsp70 was found to stimulate Hsp60 release from PBMCs and GCT cells. These responses of Hsp release were used to form a theory of a cascade-like danger signal that may occur when cells are exposed to bacterial infection and which would result in activation of antigen presenting cells via previously identified receptors for Hsps such as CD14/TLR4 or by unidentified pathways. The elevated release of Hsps in response to GroEL and LPS was also identified as a mechanism that could stimulate bone loss during infection or autoimmuniry by affecting the RANKL/OPG system. hi conclusion, Hsp60 and Hsp70 can be released from immune cells under normal conditions, and from both immune and osteoblast-like cells following stimulation with LPS and other Hsps. The observed release responses provide a mechanism through which Hsps can act as danger signals to the innate immune system, and also as promoters of bone resorption via the RANKL/OPG system.
7

COROS - Correction du déficit osseux dans la mucoviscidose. / Effects of CFTR correctors in CF bone disease

Delion, Martial 07 October 2016 (has links)
La maladie osseuse est une complication sévère pour les patients atteints de mucoviscidose (Cystic Fibrosis, CF). Les fractures vertébrales et costales impactent les capacités pulmonaires et la clairance du mucus bronchique. La meilleure prise en charge des symptômes des patients CF a permis l’amélioration de leurs qualité et espérance de vie. Cependant malgré l’optimisation de facteurs impactant le métabolisme osseux aucune amélioration notable n’a été observée dans la fragilité osseuse. Plus de 80% des patients CF sont porteurs de la mutation F508del du gène CFTR (Cystic Fibrosis Transmembrane conductance Regulator) sur au moins un allèle. L’implication directe de la mutation F508del dans la maladie osseuse a été montrée, bien que son rôle dans le dysfonctionnement du métabolisme osseux reste encore à élucider. Notre travail a permis de mettre en évidence que la mutation F508del portée par les ostéoblastes humains est responsable d’une dérégulation importante de la voie de signalisation RANK/RANKL/OPG aboutissant à un ratio RANKL/OPG élevé, potentiateur de l’ostéoclastogénèse et de la résorption osseuse. Nous avons également mis en évidence que le contexte inflammatoire chronique de la pathologie pourrait exacerber la perte osseuse, les cellules CF étant plus sensibles à ces stimulations. Par ailleurs, nous avons montré que l’utilisation de molécules pharmaceutiques comme des correcteurs et potentiateurs de CFTR, actuellement utilisés en essais cliniques, permettent une normalisation au moins partielle des dérégulations observées des ostéoblastes CF, et apparaissent comme des nouvelles stratégies thérapeutiques. / Bone disease is a serious complication for patients with Cystic Fibrosis (CF). Rib and vertebral fractures worsen lung function and mucus clearance. Better care of CF patient’s symptoms enable an improvement in life quality and expectancy. Despite optimization of factors impacting bone metabolism no improvement was observed in bone loss of patients with CF. More than 80% CF patients carried the F508del mutation on the CFTR (Cystic Fibrosis Transmembrane Conductance Regulator) gene on at least one allele. The role of the F508del mutation in the dysfunction of bone metabolism is yet unclear, but its involvement has been already shown in clinical studies and mouse models.Our work shown that F508del mutation on human osteoblasts causes a dysregulation in the RANK/RANK-L/OPG signalling leading to a high RANK-L to OPG ratio that may improve osteoclastogenesis, and thus the bone résorption. We also show that chronic inflammatory status of CF patients could exacerbate bone loss because of a high sensitivity of osteoblasts with the F508del-CFTR mutation. In addition, we demonstrate that the use of drugs as CFTR correctors and potentiators cause an improvement of the dysregulation observed and seems to be a promising therapeutic strategy.
8

Express?o imuno-hitoqu?mica das prote?nas RANK, RANKL e OPG em cistos radiculares e cistos dent?geros

Moraes, Maiara de 10 March 2010 (has links)
Made available in DSpace on 2014-12-17T15:32:19Z (GMT). No. of bitstreams: 1 MaiaraM_Dissert.pdf: 2968185 bytes, checksum: 105b46ac6fb81afd7b7596a11828a3c8 (MD5) Previous issue date: 2010-03-10 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Receptor ativador nuclear &#954;appa B (RANK), ligante do receptor ativador nuclear &#954;appa B (RANKL) e osteoprotegerina (OPG) s?o membros da fam?lia do fator de necrose tumoral relacionados com o metabolismo ?sseo. A forma??o, diferencia??o e atividade dos osteoclastos s?o reguladas por estas tr?s prote?nas. RANK ? um receptor transmembrana presente em diversos tipos celulares, principalmente em c?lulas de linhagem macrof?gica, linf?citos, c?lulas dendr?ticas e fibroblastos e quando ativado pelo seu ligante, RANKL, promove a diferencia??o e ativa??o de c?lulas osteocl?sticas respons?veis pelo processo de reabsor??o ?ssea. A OPG impede a liga??o RANK/RANKL atuando como um receptor inibit?rio para a atividade osteol?tica. O objetivo deste estudo foi comparar a express?o imuno-histoqu?mica destes biomarcadores em cistos radiculares (n=20) e cistos dent?geros (n=20). A express?o imuno-histoqu?mica destes marcadores foi avaliada no epit?lio e na c?psula dos cistos por escores e percentuais m?dios de imunomarca??o. Para o epit?lio, a an?lise semi-quantitativa revelou um padr?o similar dos escores de imunomarca??o de RANK, RANKL e OPG nas les?es, n?o havendo diferen?a estat?stica significante (p=0.589, p=0.688, p=0.709, respectivamente). Para a c?psula c?stica a an?lise quantitativa, mostrou diferen?a estat?stica significante entre os percentuais m?dios de imunomarca??o do RANK e RANKL (p=0,001 e p=0,005, respectivamente) nos cistos. A correla??o dos escores de imunomarca??o de RANKL e OPG no epit?lio do CR e do CD revelou diferen?a estat?stica significante (p=0,029, p=0,003, respectivamente). No epit?lio dos CRs e dos CDs observou-se uma maior imunoexpress?o da OPG comparada a do RANKL. Os resultados apontam a presen?a de RANK, RANKL e OPG nos cistos radiculares e cistos dent?geros, sugerindo a atua??o destas prote?nas no desenvolvimento e expans?o das les?es no osso adjacente / Receptor ativador nuclear &#954;appa B (RANK), ligante do receptor ativador nuclear &#954;appa B (RANKL) e osteoprotegerina (OPG) s?o membros da fam?lia do fator de necrose tumoral relacionados com o metabolismo ?sseo. A forma??o, diferencia??o e atividade dos osteoclastos s?o reguladas por estas tr?s prote?nas. RANK ? um receptor transmembrana presente em diversos tipos celulares, principalmente em c?lulas de linhagem macrof?gica, linf?citos, c?lulas dendr?ticas e fibroblastos e quando ativado pelo seu ligante, RANKL, promove a diferencia??o e ativa??o de c?lulas osteocl?sticas respons?veis pelo processo de reabsor??o ?ssea. A OPG impede a liga??o RANK/RANKL atuando como um receptor inibit?rio para a atividade osteol?tica. O objetivo deste estudo foi comparar a express?o imuno-histoqu?mica destes biomarcadores em cistos radiculares (n=20) e cistos dent?geros (n=20). A express?o imuno-histoqu?mica destes marcadores foi avaliada no epit?lio e na c?psula dos cistos por escores e percentuais m?dios de imunomarca??o. Para o epit?lio, a an?lise semi-quantitativa revelou um padr?o similar dos escores de imunomarca??o de RANK, RANKL e OPG nas les?es, n?o havendo diferen?a estat?stica significante (p=0.589, p=0.688, p=0.709, respectivamente). Para a c?psula c?stica a an?lise quantitativa, mostrou diferen?a estat?stica significante entre os percentuais m?dios de imunomarca??o do RANK e RANKL (p=0,001 e p=0,005, respectivamente) nos cistos. A correla??o dos escores de imunomarca??o de RANKL e OPG no epit?lio do CR e do CD revelou diferen?a estat?stica significante (p=0,029, p=0,003, respectivamente). No epit?lio dos CRs e dos CDs observou-se uma maior imunoexpress?o da OPG comparada a do RANKL. Os resultados apontam a presen?a de RANK, RANKL e OPG nos cistos radiculares e cistos dent?geros, sugerindo a atua??o destas prote?nas no desenvolvimento e expans?o das les?es no osso adjacente
9

Estudio de la distribución de determinados polimorfismos de un solo nucleótido de los genes OPG,RANK, RANKL, GNAS1 y CLDN14 y su relación con la densidad mineral ósea y diversos marcadores de remodelación ósea en el hiperparatiroidismo primario

Piedra León, María 02 September 2011 (has links)
Introducción: analizamos la relación entre fracturas y densidad mineral ósea (DMO) y los SNP (polimorfismos de un solo nucleótido) rs3102735 (163 A/G), rs3134070 (245 T/G) y rs2073618 (1181 G/C) de OPG, el SNP rs2277438 SNP de RANKL, el SNP rs7121 (393 T/C) de GNAS1 y del SNP rs219780 del gen CLDN14 en pacientes con HPP (hiperparatiroidismo primario) esporádico. Métodos: reclutamos 298 pacientes con HPP y 328 voluntarios sanos en un estudio transversal. Analizamos historia de fracturas o litiasis renal, parámetros bioquímicos, DMO en columna lumbar, cadera total, cuello femoral y radio distal y genotipado de los SNP mencionados. Resultados: no encontramos diferencias entre los genotipos de ninguno de los SNP estudiados en relación con la frecuencia de fracturas en HPP o en sujetos control. La DMO fue menor en el radio en los HPP homocigotos para el alelo menor en comparación con el resto de grupos en los SNP de OPG (163 A/G) y (245 T/G) pero no en sujetos control. En el resto de los SNP estudiados no encontramos diferencias entre genotipos y DMO en los sujetos con HPP o control excepto en el SNP de OPG (1181 G/C) en sujetos control con mayor DMO lumbar en el grupo CC respecto del GG. Conclusiones: los sujetos con HPP y homocigotos para el alelo menor (GG) en los SNP rs3102735 (163 A/G) y rs3134070 (245 T/G) de OPG tienen menor DMO en el radio distal. El resto de SNP estudiados no parecen influir en la diferente expresión de las manifestaciones óseas del HPP. / Background: we analyze the relationship between fractures and BMD (bone mineral density) and the rs3102735 (163 A/G), rs3134070 (245 T/G) and rs2073618 (1181 G/C) SNPs of the OPG, the rs2277438 SNP of the RANKL, the rs7121 SNP (393 T/C) of GNAS1 and the rs219780 of CLDN14 in patients with sporadic PHPT (primary hyperparathyroidism). Methods: We enrolled 298 Caucasian patients with PHPT and 328 healthy volunteers in a cross-sectional study. We analyzed history of fractures or renal lithiasis, biochemical determinants, BMD measurements in the lumbar spine, total hip, femoral neck and distal radius, and genotyping for the SNPs to be studied. Results: Regarding the frequency of fractures we found no differences between genotypes in any of the SNPs studied in the PHPT or in the control subjects groups. Significant lower BMD in the distal radius was found in the minor allele homozygotes (GG) compared to heterozygotes and major allele homozygotes in both OPG rs3102735 (163 A/G) and OPG rs3134070 (245 T/G) SNPs in those with PHPT but not in control subjects. We found no difference between genotypes of the rest of the SNPs studied in PHPT or control subjects with the exception of SNP OPG rs2073618 (1181 G/C) in control CC subjects which showed higher lumbar BMD than GG ones. Conclusions: Subjects with PHPT and minor homocygote genotype (GG) for the OPG rs3102735 (163 A/G) and OPG rs3134070 (245 T/G) SNPs have lower BMD in the distal radius. All the other SNPs studied do not appear to influence the different expression of HPP in bone.
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Auswirkung von Bisphosphonaten auf die Expression von Osteoprotegerin (OPG) und Receptor activator of nuclear factor êB ligand (RANKL) in Osteoblastenkulturen aus Unterkiefer und Becken - Eine Pilotstudie am Hausschwein / Effect of bisphosphonates on the expression of osteoprotegerin (OPG) and receptor activator of nuclear factor kappa B ligand (RANKL) in osteoblast cultures of the mandible and pelvis - A pilot study on the domestic pig

Sievers, Niklas 14 November 2012 (has links)
No description available.

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