Zugl.: Giessen, Universiẗat, Diss., 2008.

Zugl.: Giessen, Univ., Diss., 2009

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Instituto Dr. Josà Frota / Com o advento e com o desenvolvimento da artroscopia do ombro, as lesÃes do complexo labrum biciptal superior passaram a ser reconhecidas como fonte de disfunÃÃo nesta articulaÃÃo. Contudo, os mecanismos responsÃveis pela lesÃo continuam desconhecidos, e as hipÃteses existentes sÃo controversas. Para determinar as propriedades biomecÃnicas do complexo labrum biciptal superior e observar as alteraÃÃes ocorridas quando submetidos a traÃÃes contÃnuas e repentinas, 18 ombros congelados de 15 cadÃveres masculinos, cuja faixa etÃria variou entre 20 e 40 anos, foram submetidos a testes de traÃÃo uniaxial feitos com 3 mÃquinas distintas. O estresse que causou a ruptura do corpo de prova na traÃÃo contÃnua foi da ordem de 290N e, na traÃÃo repentina foi de 384N. Todas as lesÃes ocorreram na porÃÃo distal do tendÃo do cabo longo do bÃceps. Os resultados apontam que uma simples traÃÃo uniaxial contÃnua ou repentina no braÃo nÃo à capaz de gerar uma lesÃo SLAP / With the advent and the development of the artroscopia of the shoulder, the injuries of the complex labrum biciptal superior had started to be recognized as source of the shoulder disease. However, the responsible mechanisms for the injury continue unknown and the existing hypotheses are controversies. To determine the biomechanic properties of the complex labrum biciptal superior and to observe the occured alterations when submitted to continuous and sudden tractions, 18 frozen shoulders of 15 masculine corpses, age band between 20 and 40 years, they had been submitted to the tensile tests of made uniaxial traction with three distinct machines. Stress that it caused the rupture of the body of test in the continuous traction was of the order of 290N and, in the sudden traction was of 384N. All the injuries had occurred in the distal portion of the tendon of the long handle of the biceps. The results point that a simple continuous or sudden uniaxial traction in the arm is not capable to generate an injury SLAP

München, Techn. Univ., Diss., 2004.

No description available.

Dans le cadre de ce travail de thèse nous nous sommes intéressés à deux pathologies fémoro-acétabulaires dont la pathogénie semble liée aux « conditions biomécaniques » locales. La première partie de cette thèse était consacrée à l’analyse de l’influence de l’anatomie osseuse sur l’apparition de l’ostéonécrose aseptique de la tête fémorale. Nous avons réalisé des analyses analytique de l’anatomie des patients souffrant d’ONA (notre hypothèse était que nous retrouverions un profil anatomique particulier chez les patients souffrant d’ONA par rapport à la population générale.Nos résultats démontrent que les patients souffrant d’ONA présentent fréquemment une anatomie particulière. Notre modèle en éléments finis de la hanche de dix patients souffrant d’ONAi, a permis de valider notre hypothèse puisqu’il existe un recouvrement quasi-parfait, entre la zone de nécrose osseuse et celle supportant les contraintes fémoro-acétabulaires. L’hypothèse selon laquelle une pathogénie mécanique puisse être responsable du développement l’ostéonécrose aseptique de la tête fémorale est vérifiée par nos travaux.Dans la seconde partie de cette thèse nous avons décrit le rôle mécanique du LA par une évaluation multimodale combinant analyse cinématique,de contraintes fémoro-labrales et enfin analyse en éléments finis. Les résultats de ces études ont permis de constater que le LA se déforme lors du mouvement reflétant une transmission de contraintes fémoro-labrales lors du mouvement d’abduction. Ces contraintes ont pu être enregistrées à l’aide de capteurs piezo-resistifs, elles augmentent lors du mouvement d’abduction. Ces éléments ont été confirmés par notre modèle en éléments finis. / As parts of this thesis we focused on two femoro-acetabular diseases whose pathogenesis appears to be related to "biomechanical local conditions". The first part of this thesis was devoted to analyze the influence of bony anatomy on the development of aseptic osteonecrosis of the femoral head. We thus aimed to analyze ONA patients’ anatomy in a matched-controlled fashioned study. Our results demonstrate that patients with ONA often present a particular anatomy. A finite element model of ten iONA hips validated our hypothesis since we found an overlap between bone necrosis area and femoro-acetabular strains bearing area. The assumption that a mechanical pathogenesis may be responsible for ONA development has been confirmed by our results.If the relationship between bony anatomy and bone disease is quite intuitive, acetabular labrum involvement (AL) in the regulation of femoro-acetabular mechanical conditions is unclear. The mechanical role of the AL is widely controversial, though some authors attributed, AL, a key role in hip joint’s mechanics, others advocated its complete resection in case of painful traumatic tears. We tried to demonstrate AL’s mechanical role in a multimodal analysis combining kinematic, strains and finite element analysis. The AL deforms during abduction movement reflecting femoro-labral strains’ transmission. Those strains have been recorded using piezo-resistive sensors, they increase during adduction to abduction movement. These elements were confirmed by our finite element model: labral resection changed the Femoro-acetabular strains to the detriment of cartilage surfaces.

Subterranean termites encounter numerous kinds of fungi during foraging and feeding activities. Nearly nine decades of research have exposed only a small fraction of the termitefungal interactions that exist in nature. The first portion of research presented here focused on how feeding behaviors of Reticulitermes virginicus (Banks) were affected by the fungus Trichoderma virens (Miller, Giddens & Foster) von Arx. Tests were performed with 'P' (GLT+) and 'Q'(GLT-) strains of T. virens. Both strains were applied to filter paper and wood disks cut from southern yellow pine and Sentricon® monitoring devices. The first bioassay assessed the termites' feeding responses to fungal extracts removed from liquid media on days 2 through 7, and again on day 15. Only the GLT+ extracts from days 6 and 7 inhibited termite feeding significantly from the controls (16% and 54% less area loss, respectively). Response to wood covered by live T. virens mycelia was tested in the second bioassay. No significant differences in termite consumption were seen between fungal strains, but both substantially reduced the area loss due to termite feeding of treated wood by an average of 35%. A vacuum impregnation system was used to inoculate wood disks with fungal homogenate in the third bioassay. The wood treated with either GLT+ or GLT- homogenates did not have significant differences in area loss due to termite feeding. Overall, these results reiterated the plasticity that exists with termitefungal relationships. The second research topic addressed the applicability of labrum-based identification techniques to Reticulitermes Holmgren in Texas. Soldier labral morphology of four species, R. flavipes (Kollar), R. hageni (Banks), R. tibialis Banks, and R. virginicus (Banks), was evaluated as a character to separate species. Length and width measurements of five soldier labra were taken from each of the eight collection sites. These results were then judged against molecular analysis of the mtDNA 16S rRNA gene. Findings showed that labral shape was an unreliable diagnostic characteristic when comparing all species. A combination of length and length-towidth ratio successfully segregated all four Reticulitermes species. Comparison of a morphology-based dendogram to the phylogenetic analysis revealed a shared pattern between phenotypic and genotypic variations.

No description available.

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / O interesse de pesquisadores pelo estudo do sistema proprioceptivo vem crescendo nas Ãltimas dÃcadas. Isto à decorrente da importÃncia da integridade deste sistema no tratamento das enfermidades ortopÃdicas. Os mecanorreceptores e as terminaÃÃes nervosas livres sÃo as unidades microscÃpicas fundamentais da propriocepÃÃo e do sistema nervoso aferente. Eles transmitem ao sistema nervoso central informaÃÃes fisiolÃgicas em forma de potencial de aÃÃo, quando as estruturas articulares, cÃpsula, ligamentos e mÃsculos, sÃo submetidas ao estresse do movimento. Foram avaliadas a presenÃa e a densidade dos mecanorreceptores na cÃpsula, ligamento da cabeÃa femoral e labrum acetabular de 45 quadris masculinos. Destes, 30 foram obtidos de pacientes do sexo masculino com artrose secundÃria (grupo I) durante artroplastia e 15 de cadÃveres frescos com articulaÃÃo do quadril normal (grupo II). A idade mÃdia do grupo I foi de 56,5 e do grupo II foi de 35,6 anos. Os fragmentos obtidos foram mensurados em 2mm e corados com cloreto de ouro a 1%. ApÃs fixaÃÃo os fragmentos foram seccionados com criostato, em sÃrie de 6 micrÃmetros de espessura e submetidos à microscopia de luz. Foram identificados trÃs tipos de mecanorreceptores: Ruffini, Pacini e Golgi, alÃm das terminaÃÃes nervosas livres de acordo com a classificaÃÃo de Freeman e Wike (1967). Em cada grupo foi determinado o nÃmero e a densidade de mecanorreceptores e em seguida foram comparados os resultados. Concluiu-se que o predomÃnio das terminaÃÃes tipo Pacini no gurpo controle foi significante quando comparado com os corpÃsculos tipo Rufini (p < 0,01) e Golgi (p < 0,001).Enquanto que no grupo artrose a densidade do tipo Golgi foi menor que o tipo Pacini(p < 0,001) e terminaÃÃes nervosas livres( p < 0,01).Por outro lado, quando comparados a densidade total das terminaÃÃes nervosas nos dois grupos observou-se uma reduÃÃo significante nos quadris artrÃsicos (p = 0.008). Isto sugere fortemente que a integridade do sistema proprioceptivo parece sofrer modificaÃÃes em quadris artrÃsicos, como conseqÃÃncia da reduÃÃo do nÃmero de terminaÃÃes nervosas. Estudos eletrofisiolÃgicos futuros serÃo necessÃrios para definir o papel das terminaÃÃes nervosas e o padrÃo proprioceptivo do quadril normal do quadril artrÃsico. / Proprioceptive studies have reported growing interest in investigators in the last few decades. This is result of relevant integrity of this system in the treatment of orthopedic diseases. Mechanoreceptors and free nerve endings are the microscopy basic units from proprioception and peripheral nervous system. They transmit to the central nervous system physiological information with detection threshold when the joint are submitted to mechanical stress. The presence and density of mechanoreceptors were investigated in the capsule, teres ligament and acetabulum labrum from 45 hips joint. Of these 30 were obtained from male patients (Group I) with secondary arthrosis at open arthoplasty and 15 of fresh cadaver with normal hip joint (Group II). The mean age of group I was 56,6 and the group II was 36,5 years. The fragments obtained were measured up to 2mm and stained with gold chloride 1%. After fixation the fragments were sectioned with cryostat at serial sections of 6Âm thickness and examined using light microscopy. We identified 3 types of mechanoreceptors: Ruffini, Pacini and Golgi corpuscles, as well free nerve endings according of Freeman and Wike classified 1967. Each group was determined the number and density of mechanoreceptors and then it was compared. We conclude that the number of Pacini type was significative when it was compared with Rufini ( p < 0,01 ) and Golgi types (p< 0,001), in the normal group. However, the denstity of the Golgi type was minor compared to the Pacini ( p < 0,001) and free nerve ending ( p < 0,01 ) in the arthrosis group. Therefore, when the density total of nerve endings in normal hips were compared with arthosis hips we founded that the number decreased (p = 0.008). This is suggests strongly that the integrity of proprioceptive system seems to be modified by arthosis in consequence of nerve endings numbers. In the future, electrophysiological studies will be necessary to determine the rule of nerve endings and proprioceptive system in the normal and arthosis hip.