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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.
21

Estudo retrospectivo das características clínico-demográficas e histopatológicas e avaliação da imunoexpressão da interleucina-6, osteocalcina, osteoprotegerina e RANKL na distinção entre a displasia fibrosa e o fibroma ossificante / A retrospective study of the clinical and demographic characteristics and histopathologic evaluation and immunohistochemical interleukin-6, osteocalcin, osteoprotegerin and RANKL in the distinction between fibrous dysplasia and ossifying fibroma

Marcelo Martinson Ruiz 24 April 2017 (has links)
As lesões fibro-ósseas da região maxilomandibular constituem um grupo heterogêneo de patologias que incluem lesões de desenvolvimento, reativas (displásicas) e neoplásicas, sendo que as duas principais entidades incluídas neste grupo são a displasia fibrosa e o fibroma ossificante. Devido a grande similaridade histológica entre estas patologias a avaliação das características clínicas e imaginológicas, juntamente com os aspectos histopatológicos, são o principal método de diagnóstico diferencial, porém devido a presença de diferentes níveis de maturidade destas patologias, em diversos casos os componentes histológicos assim como seu ordenamento são muito semelhantes. A busca por um processo de diagnóstico histológico mais fundamentado, hoje inexistente, é justificada pela diferença do curso clínico assim como pela eleição do tratamento entre a displasia fibrosa e o fibroma ossificante. Desta forma o propósito deste trabalho foi realizar uma análise retrospectiva descritiva das características clínico-demográficas e histopatológicas, e estabelecer um critério de diagnóstico diferencial que associe algumas características histopatológicas padronizadas juntamente com uma análise imunoistoquímica dos fatores de atividade de remodelação óssea destas lesões. Desta forma foram aplicados diferentes marcadores proteicos e moleculares em casos previamente diagnosticados de displasia fibrosa e fibroma ossificante, objetivando direcionar um critério de diagnóstico mais preciso. Nesse estudo retrospectivo foram avaliados 54 casos, sendo 30 casos de displasia fibrosa e 24 casos de fibroma ossificante, definidos após uma revisão nas análises das lâminas seguindo um padrão com algumas particularidades histomorfológicas para o diagnóstico diferencial. As características histológicas utilizadas para essa diferenciação, baseadas na revisão da literatura, foram: 1- limite entre a lesão e o tecido ósseo adjacente; 2- depósitos esféricos basofílicos (calcificações cementóides); 3- espaços negativos limítrofes entre o tecido ósseo e o tecido conjuntivo; 4- intensidade da celularidade do estroma e; 5- paralelismo das trabéculas ósseas lesionais. Após a reavaliação das lâminas seguindo a padronização de diferenciação com os cinco critérios histológicos mencionados anteriormente, foram reconsiderados os diagnósticos de 7 lâminas, ou seja 12,96% das amostras apresentaram alteração no diagnóstico anatomopatológico inicial. Posteriormente foram utilizados os seguintes imunomarcadores proteicos e moleculares do metabolismo ósseo em 9 lâminas de fibroma ossificante e em 7 lâminas de displasia fibrosa: interleucina 6 (IL-6), osteoprotegerina (OPG), osteocalcina (OCN) e o ligante do receptor do ativador do fator nuclear Kappa B (RANKL). A imunoexpressão destes marcadores foi observada nos seguintes locais: osteócitos, osteoblastos, osteoclastos e no estroma. Apenas a osteoprotegerina apresentou significância estatística nos osteócitos, osteoblastos e osteoclastos. A osteoprotegerina no estroma e os demais marcadores não apresentaram significância estatística em nenhum dos locais. / The fibro-osseous lesions of the maxillomandibular region constitute a heterogeneous group of pathologies that include developmental, reactive (dysplastic) and neoplastic lesions, and the two main entities included in this group are fibrous dysplasia and ossifying fibroma. Due to the great histological similarity between these pathologies the evaluation of the clinical and imaging characteristics, together with the histopathological aspects, are the main method of differential diagnosis, however due to the presence of different levels of maturity of these pathologies, in several cases the histological components as well as their arrangement are very similar. The search for a more substantiated histological diagnosis process, which does not exist today, is justified by the difference in the clinical course as well as by the choice of treatment between fibrous dysplasia and ossifying fibroma. Therefore, the purpose of this study was to perform a descriptive retrospective analysis of the clinical-demographic and histopathological characteristics and to establish a differential diagnosis criterion that associates some standard histopathological characteristics together with an immunohistochemical analysis of the bone remodeling activity factors of these lesions. In this way different molecular and protein markers were applied in previously diagnosed cases of fibrous dysplasia and ossifying fibroma, aiming at directing a more precise diagnosis criterion. In this retrospective study, 54 cases were evaluated, 30 cases of fibrous dysplasia and 24 cases of ossifying fibroma, defined after a review in the analysis of the slides following a pattern with some histomorphological peculiarities for the differential diagnosis. The histological characteristics used for this differentiation, based on the literature review, were: 1- border between the lesion and the adjacent bone tissue; 2- basophilic spherical deposits (cementoid calcifications); 3 - borderline negative spaces between the bone tissue and connective tissue; 4- intensity of stroma cellularity; 5- parallelism of lesionous trabeculae. After the reassessment of the slides following the standardization of differentiation with the five histological criteria mentioned above, the diagnoses of 7 slides were reconsidered, that is, 12.96% of the samples presented alterations in the initial anatomopathological diagnosis. Subsequently, the following protein and molecular biomarkers of bone metabolism were used on 9 ossifying fibrous slides and on 7 fibrous dysplasia slides: interleukin 6 (IL-6), osteoprotegerin (OPG), osteocalcin (OCN) and the activator receptor ligand Of nuclear factor Kappa B (RANKL). Immunoexpression of these markers was observed at the following sites: osteocytes, osteoblasts, osteoclasts and in the stroma. Only osteoprotegerin presented statistical significance in osteocytes, osteoblasts and osteoclasts. The osteoprotegerin in the stroma and the other markers did not present statistical significance in any of the sites.
22

Développement et étude de la biocompatibilité d'un ciment composite phosphate de calcium-strontium et PLAGA à usages orthopédiques / Development and biocompatibility study of a new Strontium containning calcium phosphate cement and PLAGA composite for orthopaedics applications.

Romieu, Guilhem 11 March 2011 (has links)
Ce travail porte sur la mise au point, le développement et l’étude de la dégradation et de la biocompatibilité d’un nouveau ciment phosphocalcique modifié par ajout de strontium. Un ciment composite formé par l’insertion de microsphère de PLAGA a aussi été développé. Ces ciments ont un intérêt thérapeutique en orthopédie et en chirurgie maxillo-faciale pour le comblement ou le renforcement osseux. Les caractéristiques mécaniques, rhéologiques et radiologiques du ciment et du composite ont été évaluées et optimisées pour rendre leurs formulations à la fois résistantes, injectables et radio-opaque. Un travail de développement à été mené pour répondre au mieux au cahier des charges clinique de ce type de substitut osseux. La chimie de la réaction au sein du ciment à été étudiée pour connaître les mécanismes réactionnels, l’évolution et le produit final de la réaction de prise. Des tests in vitro sur la dégradation par dissolution passive des constituants du ciment et du composite ont été réalisés ainsi que l’étude de la biocompatibilité sur des cultures cellulaires. Des expérimentations animales sur la peau de souris et sur le tibia de lapin ont permis de confirmer la biocompatibilité du ciment et du composite et de donner une première évaluation de sa résorption et de son remplacement par du tissu osseux néo formé. / The aim of this thesis is to design and develop a new calcium phosphate cement modified by addition of strontium and a composite cement formed by the insertion of PLAGA microspheres.These cements have a therapeutic interest in orthopaedic and maxillofacial surgery for bone filling or reinforcement.The mechanical, rheological and radiological properties of cement and composite were evaluated and optimized to improve their mechanical strength, injectability and radio-opacity. Development works were conducted to meet clinical specifications required for this type of bone substitute.The cement chemistry was studied to determine the reaction mechanisms, evolution and the final product of the setting reaction. In vitro tests on the degradation of cement components and composites were performed and the biocompatibility was studied by cell cultures.Animal experiments on mouse skin and rabbit tibia have confirmed the biocompatibility of these cements and provide a preliminary assessment of its resorption and replacement by newly formed bone tissue.
23

Les variations osseuses asymptomatiques du squelette postcranien : leur contribution à l'identification en anthropologie médico-légale / The asymptomatic osseous variation of postcranial skeleton : their contribution to the identification in forensic anthropology

Verna, Emeline 11 December 2014 (has links)
En anthropologie médico-légale la détermination du sexe, l'estimation de l'âge au décès et l'estimation de la stature sont des paramètres essentiels à la constitution du profil biologique d'un individu à partir de restes osseux. Toutefois uniquement à partir de ces trois paramètres les interprétations sont limitées, plusieurs individus peuvent partager un même profil. L'introduction et l'observation d'autres paramètres, comme les variations anatomiques, peuvent être un atout dans l'établissement du profil biologique le plus singulier et complet possible afin de ne correspondre qu'à un nombre très restreint d'individus voire à un seul individu. En plus des variations anatomiques, l'observation des marqueurs de posture et des anomalies congénitales asymptomatiques peut aussi se révéler être pertinente. Ils ont été regroupés sous le terme de Variations Osseuses Asymptomatiques (VOA). Cent-neuf VOA ont été recensées sur le squelette postcrânien et 82 ont été étudiées à partir de 1300 individus provenant de trois populations différentes : une population contemporaine (imagerie médicale), une population ostéologique de référence et une population ostéoarchéologique. Pour chacune des VOA, la fréquence a été obtenue à partir des trois échantillons puis une fréquence en fonction du sexe, de l'âge et de la latéralité a été calculée. Une iconographie claire de chaque VOA a été obtenue. L'intérêt final est de ne sélectionner que les VOA ayant une fréquence inférieure à 10 % et facilement observables afin d'aider à l'identification en complétant le profil biologique, et ceci à partir d'une méthode basée sur la comparaison de données ante et post-mortem. / In forensic anthropology, determination of sex, estimation of age at death and estimation of stature are essential parameters for constituting the biological profile of an individual from bone remains. However, using only three parameters limits interpretation, several individuals could share the same profile. The introduction and observation of others parameters, particularly anatomical variations, could help establish a more complete and specific biological profile to correspond to a restricted number of individuals or to a unique individual. In addition to anatomical variations, postural markers and congenital anomalies can be useful for identification purposes. These 3 elements are regrouped under the term Asymptomatic Osseous Variation (AOV). 109 AOVs were found on the postcranial skeleton and 82 were studied on 1300 individuals from three different populations: a contemporary population (medical imaging), an osteological collection of reference and an osteoarcheological population. Frequencies were obtained from the three samples for each AOV, and frequencies according to sex, age and laterality were calculated. A clear iconography of each AOV was obtained. This data enabled the classification of the AOVs according to 5groups of frequencies, ranging from very rare to very frequent. The AOVs were also classified according to their liaison with sex, age and laterality. The final goal is to select only AOVs with a frequency inferior to 10% (qualified as rare), that are easily observable, to be useful for establishing the biological profile and help identify the individual, using a method based on ante and post-mortem data comparison.
24

Caractérisation techno-économique d'industries en bois de cervidés du Badegoulien et du Magdalénien : le cas du Rond-du-Barry (Haute-Loire) et de Rochereil (Dordogne) / Non communiqué

Rémy, Delphine 02 December 2013 (has links)
L’analyse technologique des industries osseuses paléolithiques est une discipline encorerelativement jeune. Nous avons appliqué cette méthode d’analyse à deux assemblages : celuide la grotte du Rond-du-Barry (Haute-Loire) qui a livré une longue séquence allant duBadegoulien ancien au Magdalénien supérieur ; et celui de la grotte de Rochereil (Dordogne)qui a livré un ensemble attribué au Magdalénien supérieur.Dans une perspective synchronique, l’analyse technologique a permis de défi nir les modalitésd’exploitation des bois de cervidés dans ces gisements pour chaque période envisagée duBadegoulien ancien jusqu’au Magdalénien supérieur, pour les replacer dans le contexte généralde ces groupes chrono-culturels tels qu’ils sont connus à l’heure actuelle.Dans une perspective diachronique, nous analysons dans leur aspect technologique leschangements qui sont intervenus dans le travail des bois de cervidés entre le Badegoulien etle Magdalénien, changements qui se caractérisent avant tout par l’abandon du débitage parpercussion directe et le retour au débitage par double rainurage. Enfi n nous discutons du rôleet du statut qu’ont pu détenir ces deux gisements dans leur contexte local et régional. / Technological analysis of paleolithic bone industries is a still relatively young discipline. Weapplied this method to the material from two sites: the Rond-du-Barry (Haute-Loire) whichdelivered a long sequence from ancient Badegoulian to upper Magdalenian ; and Rochereil(Dordogne) which delivered an assemblage attributed to upper Magdalenian.In a synchronic perspective, the technological analysis allowed to defi ne the modalitiesof exploitation of antler in these sites for every period, from ancient Badegoulien to upperMagdalenian, and then to replace them in the general context of these chrono-cultural groupssuch as they are known at the moment.In a diachronic perspective, we analyze, in their technological aspect, the changes thatoccurred in antlerworking between the Badegoulian and the Magdalenian, which are aboveall characterized by the abandonment of the debitage by direct percussion and the groove andsplinter technique. Finally we discuss the role and the status of these two sites in their localand regional context.
25

Smarcal1 promotes double-strand-break repair by nonhomologous end-joining / Smarcal1は非相同末端結合によるDNA二重鎖切断修復を促進する

Shamima, Keka Islam 25 January 2016 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第19401号 / 医博第4052号 / 新制||医||1012(附属図書館) / 32426 / 京都大学大学院医学研究科医学専攻 / (主査)教授 髙田 穣, 教授 平岡 眞寛, 教授 松本 智裕 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
26

Spill : Om djur, hantverk och nätverk i Mälarområdet under vikingatid och medeltid / Waste : Osseous materials, craft and networks in the Mälaren region during the Middle Ages

Karlsson, Johnny January 2016 (has links)
This thesis examines the use of various osseous raw materials in craft activities in the Mälaren region during the Middle Ages. Places studied are: Birka, Sigtuna, Nyköping, Strängnäs and Uppsala. The aim is to capture both chronological and spatial changes in the use of osseous raw materials. Species and materials used reflect regional as well as international networks and how they change during time. The spatial distribution of waste from craft activities, its materiality and temporality mirror activities in different social contexts.  Quantitative and qualitative changes in the handling and exploitation of raw materials reflect varying and changing views of its value and how craft and exchange is affected by both a social and economic agency. In Birka, osseous waste material associated with craft was collected by Hjalmar Stolpe in the 1870s. An examination of the assemblage shows that imported material comprises a significant part of the collection. About a third of the waste consists of imported antler of red deer and reindeer. Red deer is particularly abundant (21%), signifying the importance of southern trading networks. The presence of whalebone can also be linked to south-western trading routes. The waste material collected during excavations in Sigtuna and representing the period c. 980-1300 has a different composition, reflecting different networks and perhaps different means of trade and production. As in Birka, elk antler constitutes the main bulk of the raw material used. Red deer antler is extremely limited, forming less than 1% of the material, appearing continuously though in small amounts from c. 1020-1300.  Reindeer antler is distinctly present in the oldest phase, c. 980-1000. This occurrence might represent a relic of the northern network manifested at Birka. An isotopic study indicates an origin in a forested biotope. After this initial phase the use of reindeer antler becomes as rare as that of red deer until the second half of the 12th century, indicating that the antler craft operated on a minor scale without any demand for long-distance trade in raw materials. A change occurs in the last quarter of the 12th century when large quantities of reindeer antler appear once more. Isotope signatures indicate an origin in more mountainous regions. This coincides with the introduction of another traded raw material of an arctic origin: walrus tusk. The craft had become more marked oriented. This is manifested in larger deposits of debris, a wider range of materials used, including bones from various domestic animals, but also the handling and exploitation of the material changes indicating a different view of production, trade and the value of raw materials than previous. This shift coincides with the introduction of minted silver. Western influences are evident both in the material culture and in the faunal assemblage. It is likely that a majority of the reindeer antler as well as the walrus tusk present in these later phases have a Norwegian origin. In the late 1100s and early 1200s craft in osseous material occur in other towns that emerge in the region but it seems to appear in new social contexts. Small assemblages of antler debris have been found in Uppsala, but the activities they represent lack the spatial continuity that exist in contemporary environments in Sigtuna and Strängnäs, indicating short lived occasional activities in a loosely regulated urban environment. Craft activities dependent purely on bone from domestic animals appear in the 1200s in Nyköping, Uppsala and Strängnäs. They represent craft activities in a new social context outside the private sphere of the local elite and instead subordinated other craft activities where domestic animals have been exploited on a large scale beyond the domestic household. Antler craft represents a social practise in the realms of the local elite with a continuity stretching back to the Iron Age. Monetization and an increasingly feudal society redefine social relations and practise. This can be seen in the occurrence of craft in new contexts in the late 1100s and 1200s, reflecting heterogeneity in social and economic functions in and between the towns in the region.
27

Contribution de l'analyse mécanique à l'étude des implants et des biomatériaux dentaires

Faudemer, Gonzague 14 February 2013 (has links)
La solution la plus favorable cliniquement au remplacement des dents absentes est aujourd’hui la mise en place d’implants dentaires. Cette technique nécessite la maîtrise de plusieurs problématiques qui s’articulent autour des interfaces du système. Celles-ci sont au nombre de trois soit : l’interface os-implant, l’interface implant-pilier prothétique et l’interface pilier prothétique-prothèse. Dans cette étude, nous analysons les matériaux mis en présence au sein des interfaces et ce, par le biais de l’analyse mécanique afin d’apporter une contribution objective au choix clinique des matériaux par les praticiens. Les substituts osseux sont ainsi étudiés sous le prisme de leur stabilité mécanique, servant de trame à la reconstruction osseuse au contact de l’implant. Plusieurs systèmes implantaires (ensemble implant-pilier prothétique) sont ensuite étudiés pour en évaluer également la stabilité, gage de solidité du système et d’absence de dévissage. Enfin, plusieurs polymères dentaires sont évalués et comparés afin d’établir leur apport dans la solidité du complexe implanto-prothétique. / Today, the most favorable clinical solution for replacing absent teeth are dental implants. Several problems has to be addressed to master this technique, in particular those concerning the design of the many interfaces of this system. The three main interfaces are : the bone-implant junction, the implant-prosthetic pillar contact and prosthetic pillar-prosthesis assembly. In this study, the mechanical behavior of the constitutive materials of the system is evaluated to supply unbiased criteria to the practitioners for selecting the right materials in clinical conditions. Thus, bones substitutes are studied to evaluate their mechanical stability which is necessary condition to ensure bone reconstruction in contact with the implant surface. Then, several implant systems (implant + prosthetic pillar) are tested to estimate their stability, which guaranty solid system and prevent from any unscrewing failure. Finally, several dental polymers are evaluated and compared to establish their contribution in the implanto-prosthetic system robustness.
28

Avaliação in vivo de matrizes tridimensionais de quitosana para a bioengenharia tecidual óssea

Carvalho, Flávio Augusto Aquino January 2008 (has links)
Submitted by Suelen Reis (suziy.ellen@gmail.com) on 2013-04-23T17:27:20Z No. of bitstreams: 1 Dissertacao - Flavio de Carvalho.pdf: 5659909 bytes, checksum: d5f85d5e5192dc307c143bf509b82aac (MD5) / Approved for entry into archive by Rodrigo Meirelles(rodrigomei@ufba.br) on 2013-05-08T12:05:01Z (GMT) No. of bitstreams: 1 Dissertacao - Flavio de Carvalho.pdf: 5659909 bytes, checksum: d5f85d5e5192dc307c143bf509b82aac (MD5) / Made available in DSpace on 2013-05-08T12:05:02Z (GMT). No. of bitstreams: 1 Dissertacao - Flavio de Carvalho.pdf: 5659909 bytes, checksum: d5f85d5e5192dc307c143bf509b82aac (MD5) Previous issue date: 2008 / Este estudo avaliou o comportamento histomorfológico in vivo de matrizes tridimensionais de quitosana com 4% e 15% de graus de acetilação, em um defeito crítico de 9mm de diâmetro criado em calvária de rato. Sessenta ratos Wistar albinus, dispostos em três grupos, foram avaliados. No grupo GI (grupo controle) o defeito foi preenchido apenas com coágulo sanguíneo; no grupo GII, o defeito foi preenchido com uma biomatriz de quitosana de 4% de grau de acetilação; no grupo GIII o defeito foi preenchido com uma matriz de quitosana de 15% de grau de acetilação, avaliados nos pontos biológicos de 7, 15, 45 e 120 dias. Os resultados demonstraram não haver diferenças significantes entre os grupos avaliados, quanto ao reparo ósseo, que se manteve limitado às bordas ósseas do defeito, de forma reparativa. Os grupos GII e GIII apresentaram uma reação inflamatória predominantemente granulomatosa, com deposição de tecido fibroso entre os biomateriais implantados. Concluiu-se que ambos os biomateriais foram biocompatíveis, entretanto não houve neoformação óssea associada à sua implantação. / Salvador
29

Kulturkontakter i Sydskandinavien under mesolitikum : Hantverkstraditioner, råmaterialval och mobilitet för 9000 år sedan, med utgångspunkt från Norje Sunnansund i Blekinge

Kjällquist, Mathilda January 2020 (has links)
The purpose of this thesis is to investigate different scales of mobility and social networks in Southern Scandinavia around 7000 BC. An essential basis for this work is the hypothesis that the conical core pressure blade technology, a specific method for producing lithic blades, reached Scandinavia from the east. The process has been discussed and verified in several earlier studies. The study is based on investigations of lithic material and bone tools, as well as human skeletal remains; a multidisciplinary strategy has been applied, which combines technological analyzes of archaeological material with isotope analyzes of human teeth. Materials and data have been collected from a total of 111 sites located mainly in Scandinavia, but also in Finland, the Baltic countries and Russia. The Mesolithic site Norje Sunnansund in Blekinge, southern Sweden is in focus. Analyzes of the chaîne opératoire of lithic and osseous production make it possible to study technological processes as the transmission of culturally conditioned patterns; these patterns underlie the formative principles of each technology complex. By identifying specific traditional knowledge built into the material process, it becomes possible to define prehistoric human traditions and thereby study human interactions and migrations between geographical regions. The analyzes of strontium isotopes in human teeth from Norje Sunnansund enables an additional individual provenancing since the isotopes reflect a geographical-geological variation. The study provides a higher resolution of the arrival and spreading of the pressure blade technology from the northeast. It also strengthens the picture of a Mesolithic society in Southern Scandinavia based on geographically extensive social networks. An increased regionalization and territorialization has previously been proposed for western Scandinavia around 8800-7500 BC. The study confirms that during this period the population seem to consist of several subgroups related to specific territories, but with close and regular contact within a more extensive social network. This fits well with the picture of a group that may have inhabited Norje Sunnansund for extended periods, while social contacts were maintained over longer distances.
30

The efficacy of BM-MSC in reconstructing large craniofacial defects and the immune response at local defect sites

Tee, Boon Ching January 2018 (has links)
No description available.

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