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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.
51

Assessing the utility of 3D modeling with photogrammetry in assigned sex estimation from the greater sciatic notch

Carrière, Chelsea Madison 15 February 2024 (has links)
Assigned sex estimation via the greater sciatic notch (GSN) is traditionally performed via physical/visual examination and ordinal scoring; however, this relies on the subjective assessment of morphology for typological classification which may not be reflective of human variation. Three-dimensional (3D) photogrammetry may offer a technologically advanced, low cost, and more objective alternative to assess the complex curvature of anatomical landmarks. This research explores the accuracy of photogrammetry derived 3D models by comparing digital measurements to those obtained from the skeletal elements and to streamline the application of curvature analysis for the estimation of assigned sex from the GSN. This study utilizes the left and right os coxae from 15 skeletal individuals (5 females, 10 males) from the Boston University Chobanian & Avedisian School of Medicine. A Fujifilm X-Pro2 and Fujifilm 35 mm prime lens captured 123 images per element, which were processed in Meshroom by AliceVision® to create a 3D textured mesh. The mesh was exported into Blender for cleanup, scaling, measurement, and curvature analysis. The measurements were between 96.54% and 99.94% consistent across methods and observations. The consistency between digital metric observations increased by an average of 0.07% when compared to the consistency of the dry bone measurements. Additionally, curvature analysis of the GSN correctly estimated the assigned sex of all os coxae in the sample. This study demonstrates that photogrammetry is an accurate and reliable method for the digitization of remains that enables analytical techniques to better capture skeletal variation compared to traditional methods.
52

Short Term Electrical Stimulation for Isograft Peripheral Nerve Repair and Functional Recovery

Pylypiv, Galina Yevgenivna 11 June 2018 (has links)
No description available.
53

Os efeitos do ultra-som terapêutico no tratamento das lesões por esmagamento do nervo ciático de ratos / The effect of the therapeutical ultrasound in the treatment of the injuries for crushing of the ciático nerve of rats

Raso, Vanessa Vilela Monte 24 January 2002 (has links)
Foi realizado um estudo experimental da influência do ultra-som terapêutico na regeneração do nervo ciático submetido a esmagamento controlado, em ratos. Foram empregados no estudo 20 ratos da linhagem Wistar, de peso médio em torno de 250 g, divididos em dois grupos, conforme o tipo de procedimento realizado: 1) somente esmagamento, dez ratos; e 2) esmagamento e irradiação com ultra-som, 10 ratos. Sob anestesia, o nervo ciático era exposto na coxa direita do animal e esmagado com um dispositivo especialmente idealizado e confeccionado para essa finalidade, com uma carga fixa de 15 Kg, por 10 minutos, num segmento de 5 mm proximal à sua bifurcação. A irradiação com o ultra-som pulsado (1:5, freqüência de 1 MHz, intensidade de 0.4 W/'CM POT.2', duração de 2 minutos) era iniciada já no primeiro dia pós-operatório e realizada por dez dias consecutivos. Os resultados foram avaliados pela análise funcional da impressão plantar dos animais obtidas numa pista de marcha e determinação do índice funcional do ciático (De Medinaceli e Bain, Mackinnon e Hunter), e pela morfometria, através do cálculo da densidade de fibras nervosas, após sacrifício dos animais no vigésimo primeiro dia pós-operatório. Os resultados foram submetidos a análise estatística e mostraram que, nas condições do trabalho, o ultra-som acelerou a regeneração do nervo, demonstrável com significância no vigésimo primeiro dia pós-operatório / An experimental study of the influence of therapeutic ultrasound on the regeneration of the sciatic nerve submitted to controlled crush injury was carried out in rats. Twenty female Wistar rats weighing 250 g on average were used and distributed in two groups according to the procedure: 1) crush injury only, ten rats; 2) crush injury followed by ultrasound irradiation, ten rats. Under general anesthesia the sciatic nerve was exposed on the right thigh and crushed with a device especially devised and built for that purpose, with a 15 kg constant load for 10 minutes, affecting a 5 mm-long segment of the nerve proximal to its bifurcation. Pulsed ultrasound irradiation (1:5, 1 MHz frequency, 0.4 W/'CM POT.2' intensity, 2 minutes duration) was started the day after the operation and repeated for ten consecutive days. The results were evaluated by functional footprint analysis and determination of the sciatic functional index (DeMedinaceli's and Bain, Mackinnon and Hunter's methods) at weekly intervals, and by morphometry (nerve fiber density) of the resected sciatic nerve after killing the animals on the 21st postoperative day. Results were submitted to statistical evaluation and showed that, in the conditions of the study, ultrasound accelerated nerve regeneration, as demonstrated with significance on the 21st postoperative day
54

Índice funcional do ciático nas lesões por esmagamento do nervo ciático de ratos. Avaliação da reprodutibilidade do método entre examinadores / Sciatic functional index assessment to evaluate functional recovery following a crush injury of the sciatic nerve of rats. Inter-personal reproducibility of the method

Raso, Vanessa Vilela Monte 31 January 2006 (has links)
Foi avaliada a reprodutibilidade entre examinadores do método de avaliação do Índice Funcional do Ciático (IFC), medido por um programa de computação desenvolvido para este fim. Foram empregados 20 ratos Wistar, cujo nervo ciático direito era abordado sob anestesia geral e esmagado num segmento de 5 mm proximal à sua trifurcação com um dispositivo especial, com carga fixa de 5 kgf por 10 minutos. Impressões das pegadas dos animais foram obtidas na fase pré-operatória e, depois, semanalmente, da 1ª à 8ª semana pós-operatória, em uma pista de marcha. As impressões eram digitalizadas, armazenadas e avaliadas, pela medida de parâmetros pré-determinados, por quatro examinadores, seguindo sempre a mesma seqüência de marcação dos parâmetros. Os resultados foram submetidos à análise estatística, que mostrou haver um alto índice de correlação entre examinadores na avaliação pré-operatória e nas 3a, 4a, 5a, 7a e 8a semanas (igual ou maior que 0,82), com queda casual na 6a semana, mas manteve significante como as demais (pF?0,01). Na 1a e 2a semanas, o índice de correlação foi próximo de zero, mostrando a pouca reprodutibilidade do método nesse período, em que a variabilidade entre os animais não diferiu da variabilidade entre os examinadores (pF?0,24 e 0,32, respectivamente), devido à pouca definição das impressões das pegadas. / The Sciatic Functional Index (SFI) is a quite useful tool to evaluate functional recovery of the sciatic nerve of rats in a number of experimental lesions and treatment. Although being an objective method, it depends on the examiner?s ability to adequately recognize and mark the previously established footprint landmarks, which is an entirely subjective step, thus potentially interfering with the calculations according to the mathematical formulae proposed by different authors. An inter-personal evaluation of the reproducibility of an SFI computer aided method was then carried out here to study data variability. A severe crush injury was produce on a 5 mm-long segment of the right sciatic nerve of 20 Wistar rats (5kgf load directly applied for 10 minutes) and the SFI was measured by four different examiners (2 experienced and 2 new-comers) either preoperatively and at weekly intervals from the 1st to the 8th postoperative week. Three measurements were made for each print and an average was drawn and used for the statistical analysis. The results showed that interexaminer correlation was high (0.82) on the 3rd, 4th, 5th, 7th and 8th weeks, with an unexpected (pF?0.01) drop on the 6th week. There was virtually no inter-personal correlation (correlation index nearly 0) on the 1st and 2nd weeks, period in which the variability between animals (pF?0.24) and examiners (pF?0.32) was similar, certainly due to the poor definition of the footprints. The authors conclude that the SFI method studied here is only reliable from the 3rd week on.
55

Índice funcional do ciático nas lesões por esmagamento do nervo ciático de ratos. Avaliação da reprodutibilidade do método entre examinadores / Sciatic functional index assessment to evaluate functional recovery following a crush injury of the sciatic nerve of rats. Inter-personal reproducibility of the method

Vanessa Vilela Monte Raso 31 January 2006 (has links)
Foi avaliada a reprodutibilidade entre examinadores do método de avaliação do Índice Funcional do Ciático (IFC), medido por um programa de computação desenvolvido para este fim. Foram empregados 20 ratos Wistar, cujo nervo ciático direito era abordado sob anestesia geral e esmagado num segmento de 5 mm proximal à sua trifurcação com um dispositivo especial, com carga fixa de 5 kgf por 10 minutos. Impressões das pegadas dos animais foram obtidas na fase pré-operatória e, depois, semanalmente, da 1ª à 8ª semana pós-operatória, em uma pista de marcha. As impressões eram digitalizadas, armazenadas e avaliadas, pela medida de parâmetros pré-determinados, por quatro examinadores, seguindo sempre a mesma seqüência de marcação dos parâmetros. Os resultados foram submetidos à análise estatística, que mostrou haver um alto índice de correlação entre examinadores na avaliação pré-operatória e nas 3a, 4a, 5a, 7a e 8a semanas (igual ou maior que 0,82), com queda casual na 6a semana, mas manteve significante como as demais (pF?0,01). Na 1a e 2a semanas, o índice de correlação foi próximo de zero, mostrando a pouca reprodutibilidade do método nesse período, em que a variabilidade entre os animais não diferiu da variabilidade entre os examinadores (pF?0,24 e 0,32, respectivamente), devido à pouca definição das impressões das pegadas. / The Sciatic Functional Index (SFI) is a quite useful tool to evaluate functional recovery of the sciatic nerve of rats in a number of experimental lesions and treatment. Although being an objective method, it depends on the examiner?s ability to adequately recognize and mark the previously established footprint landmarks, which is an entirely subjective step, thus potentially interfering with the calculations according to the mathematical formulae proposed by different authors. An inter-personal evaluation of the reproducibility of an SFI computer aided method was then carried out here to study data variability. A severe crush injury was produce on a 5 mm-long segment of the right sciatic nerve of 20 Wistar rats (5kgf load directly applied for 10 minutes) and the SFI was measured by four different examiners (2 experienced and 2 new-comers) either preoperatively and at weekly intervals from the 1st to the 8th postoperative week. Three measurements were made for each print and an average was drawn and used for the statistical analysis. The results showed that interexaminer correlation was high (0.82) on the 3rd, 4th, 5th, 7th and 8th weeks, with an unexpected (pF?0.01) drop on the 6th week. There was virtually no inter-personal correlation (correlation index nearly 0) on the 1st and 2nd weeks, period in which the variability between animals (pF?0.24) and examiners (pF?0.32) was similar, certainly due to the poor definition of the footprints. The authors conclude that the SFI method studied here is only reliable from the 3rd week on.
56

Os efeitos do ultra-som terapêutico no tratamento das lesões por esmagamento do nervo ciático de ratos / The effect of the therapeutical ultrasound in the treatment of the injuries for crushing of the ciático nerve of rats

Vanessa Vilela Monte Raso 24 January 2002 (has links)
Foi realizado um estudo experimental da influência do ultra-som terapêutico na regeneração do nervo ciático submetido a esmagamento controlado, em ratos. Foram empregados no estudo 20 ratos da linhagem Wistar, de peso médio em torno de 250 g, divididos em dois grupos, conforme o tipo de procedimento realizado: 1) somente esmagamento, dez ratos; e 2) esmagamento e irradiação com ultra-som, 10 ratos. Sob anestesia, o nervo ciático era exposto na coxa direita do animal e esmagado com um dispositivo especialmente idealizado e confeccionado para essa finalidade, com uma carga fixa de 15 Kg, por 10 minutos, num segmento de 5 mm proximal à sua bifurcação. A irradiação com o ultra-som pulsado (1:5, freqüência de 1 MHz, intensidade de 0.4 W/'CM POT.2', duração de 2 minutos) era iniciada já no primeiro dia pós-operatório e realizada por dez dias consecutivos. Os resultados foram avaliados pela análise funcional da impressão plantar dos animais obtidas numa pista de marcha e determinação do índice funcional do ciático (De Medinaceli e Bain, Mackinnon e Hunter), e pela morfometria, através do cálculo da densidade de fibras nervosas, após sacrifício dos animais no vigésimo primeiro dia pós-operatório. Os resultados foram submetidos a análise estatística e mostraram que, nas condições do trabalho, o ultra-som acelerou a regeneração do nervo, demonstrável com significância no vigésimo primeiro dia pós-operatório / An experimental study of the influence of therapeutic ultrasound on the regeneration of the sciatic nerve submitted to controlled crush injury was carried out in rats. Twenty female Wistar rats weighing 250 g on average were used and distributed in two groups according to the procedure: 1) crush injury only, ten rats; 2) crush injury followed by ultrasound irradiation, ten rats. Under general anesthesia the sciatic nerve was exposed on the right thigh and crushed with a device especially devised and built for that purpose, with a 15 kg constant load for 10 minutes, affecting a 5 mm-long segment of the nerve proximal to its bifurcation. Pulsed ultrasound irradiation (1:5, 1 MHz frequency, 0.4 W/'CM POT.2' intensity, 2 minutes duration) was started the day after the operation and repeated for ten consecutive days. The results were evaluated by functional footprint analysis and determination of the sciatic functional index (DeMedinaceli's and Bain, Mackinnon and Hunter's methods) at weekly intervals, and by morphometry (nerve fiber density) of the resected sciatic nerve after killing the animals on the 21st postoperative day. Results were submitted to statistical evaluation and showed that, in the conditions of the study, ultrasound accelerated nerve regeneration, as demonstrated with significance on the 21st postoperative day
57

A Comparative Analysis of Local and Global Peripheral Nerve Mechanical Properties During Cyclical Tensile Testing

Doering, Onna Marie 05 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Understanding the mechanical properties of peripheral nerves is essential for chronically implanted device design. The work in this thesis aimed to understand the relationship between local deformation responses to global strain changes in peripheral nerves. A custom-built mechanical testing rig and sample holder enabled an improved cyclical uniaxial tensile testing environment on rabbit sciatic nerves (N=5). A speckle was placed on the surface of the nerve and recorded with a microscope camera to track local deformations. The development of a semi-automated digital image processing algorithm systematically measured local speckle dimension and nerve diameter changes. Combined with the measured force response, local and global strain values constructed a stress-strain relationship and corresponding elastic modulus. Preliminary exploration of models such as Fung and 2-Term Mooney-Rivlin confirmed the hyperelastic nature of the nerve. The results of strain analysis show that, on average, local strain levels were approximately five times smaller than globally measured strains; however, the relationship was dependent on global strain magnitude. Elastic modulus values corresponding to ~9% global strains were 2.070 ± 1.020 MPa globally and 10.15 ± 4 MPa locally. Elastic modulus values corresponding to ~6% global strains were 0.173 ± 0.091 MPa globally and 1.030 ± 0.532 MPa locally.
58

Unterschiedliche Wirkungen der TNF-alpha-Rezeptoren auf De- und Regeneration peripherer NervenEine Studie an TNF-alpha-Rezeptor-Knockoutmäusen in zwei verschiedenen Tiermodellen für Nervenläsionen / Different effects of TNF-alpha-receptors on de- and regeneration of the peripheral nerveA study in TNF-alpha-receptor-knockout-mice in two different models of nerve injury

Stallforth, Sabine January 2007 (has links) (PDF)
Noch immer ist die Behandlung von Neuropathien mit den gängigen therapeutischen Mitteln für viele Patienten sehr unbefriedigend. Als erfolgsversprechender therapeutischer Ansatz werden zur Zeit Wege erforscht, welche direkt in die molekularen Entstehungsmechanismen pathologischer Veränderungen und regenerationsfördernder Mechanismen eingreifen, um dadurch eine Heilung von Nervenschäden zu ermöglichen. Bisher sind die Erkenntnisse über diese Mechanismen nicht vollständig genug, um daraus eine sichere Behandlungsmöglichkeit abzuleiten. Wegweisende Erkenntnisse deuten sich allerdings durch Studien von unterschiedlichen Vertretern des Zytokinnetzwerkes an - darunter auch TNF-alpha - welche als molekulare Ursache neuropathischer Veränderungen diskutiert werden. In dieser Studie wurde an Knockoutmäusen der Einfluss des jeweiligen TNF-alpha-Rezeptors auf morphologische Veränderungen nach CCI (Chronic constriction injury) und Crush-Verletzung des N. ischiadicus untersucht. Nach 3,7,15 und 36 Tagen (CCI) bzw. 3,7 und 28 Tagen (Crush) wurden in Methylenblau gefärbten Semidünnschnitten intakte und degenerierte Nervenfasern, Makrophagen, Angioproliferation, Ödembildung udn Veränderung des Anteils nicht neuronaler Zellen lichtmikroskopisch beurteilt. Zusätzlich wurden Mac-1+ Makrophagen immunzytochemisch erfasst. Die Ergebnisse zeigten in beiden Modellen und bei beiden Knockouttypen eine starke axonale Schädigung, die von einer großen endoneuroalen Makrophagenansammlung begleitet war. Bei TNF-R1-/- Mäusen war eine stärkere und verlängerte Degeneration mit entsprechend höheren Makrophagenzahlen sichtbar. In den Immunzytochemischen Färbungen wiesen die TNF-R1-/- Mäuse hingegen den geringsten Makropahgenanteil auf.Trotz der starken Schädigung war die anschließende Regeneration im Gegensatz zu WT und TNF-R2-/- Mäusen besser. Die Ödembildung war bei den TNF-R2-/- nach CCI besonders stark ausgeprägt und von einer schlechten Regeneration gefolgt. Während die gefundenen Daten auf eine Beteiligung beider Rezeptoren während degenerativer Prozesse hindeuten, scheint insbesondere TNF-R2 regenerationsfördernde Effekte zu vermitteln. / Current Treatment of neuropathic disorders is still dissatisfactory for many patients. A promising approach is the investigation of agents that directly interfere with molecular development of pathologic changes and regeneration. Up to now, consolidated findings of the underlying mechanisms are not yet sufficent to allow therapeutic intervention. Pathbreaking findings come from studies investigating different agents of the cytokine network - as e.g. TNF-alpha - that are discussed as molecular cause of neuropathic changes. This study investigated the influence of both TNF-alpha-receptors on morphologic changes after CCI (chronic constriction injury) and crush-injury of the sciatic nerve of TNF-R-knockoutmice. After 3,7,15 and 36 days (CCI), and 3,7 and 28 respectively (Crush),intact and degenerating nerve fibers, macrophages, angioproliferation, development of edema and changes in the amount of non-neuronal cells were acquired by light microscopy of toluidin-stained semithin sections. Additionally Mac-1+ macrophages were acquired via immuncytochemically stained sections. The results showed strong axonal damage in both knockout-types accompanied by large amounts of endoneurial macrophages. TNF-R1-/-mice showed a longer degeneration phase including respectively higher amounts of macrophages. In contrast the TNF-R1-/-mice revealed the fewest amount of macrophages in immunocytochemical sections. Despite the strong damage better nerve regeneration was observed compared to WT and TNF-R2-/-mice. Formation of edema was pronounced in TNF-R2-/- after CCI and followed by poorly regeneration. Whereas these findings point to a participation of both receptors in degeneration, TNF-R2 seems to support regeneration.
59

Análise funcional e histológica da utilização da hialuronidase durante a anestesia local em nervo ciático de ratos / Functional and histological analysis of hyaluronidase use during local anesthesia of the rat sciatic nerve

Horliana, Anna Carolina Ratto Tempestini 29 August 2008 (has links)
O uso concomitante da enzima hialuronidase (H) ao anestésico local (AL) é muito utilizado para melhorar a eficácia anestésica em oftalmologia; em odontologia, no entanto, não mostrou vantagens. Um novo protocolo foi testado com o objetivo de prolongar a anestesia local sem a realização de complementação anestésica. Esta possibilidade seria especialmente interessante para pacientes que apresentam restrição de dose máxima recomendada de AL ou vasoconstritor (ex. cardiopatas). Utilizou-se cloridrato de lidocaína 2% com epinefrina para bloqueio sensitivo, motor e proprioceptivo no nervo ciático em ratos (Truant,1958). Hialuronidase 75 UTR (unidade de turbidade reduzida) foi injetada no mesmo local 30 minutos após o início da analgesia (antes do término do efeito anestésico), utilizando-se a pata contralateral como controle (injeção de solução anestésica e veículo da hialuronidase solvente). A duração do bloqueio sensitivo foi avaliada através da ausência do reflexo de retirada da pata, utilizando-se um analgesímetro. O bloqueio motor foi avaliado pela duração da claudicação e da ausência do reflexo de estiramento da pata, enquanto o bloqueio proprioceptivo foi avaliado pela perda dos reflexos de salto e do reposicionamento da pata (Thalhammer et al., 1995). Foi também estudada a alteração tecidual induzida pela hialuronidase nos períodos de 1 h, 24 h, 48 h e 72 h pós-injeção. Foram avaliados os grupos: (1) falso operado (Sham); (2) AL +H; (3) AL+ solvente (Solv) e (4) Solv+Solv. Concluiu-se que a hialuronidase prolonga a duração de ação anestésica local quando injetada isoladamente antes da regressão do bloqueio de condução do nervo ciático de rato. Em todos os grupos analisados, exceto o grupo falso-operado, observou-se reação inflamatória após as injeções. Esta inflamação foi mais acentuada no grupo hialuronidase, que mostrava sinais de regressão após 72 horas. É possível que o mecanismo de ação da hialuronidase envolva a desorganização do tecido conjuntivo na região da injeção, facilitando a difusão da solução anestésica residual até o nervo. / The concomitant use of the enzyme hyaluronidase (H) and local anesthetics (LA) is widely employed in ophthalmology in order to improve the effectiveness of anesthesia; in dentistry, however, this association did not seem advantageous. A new protocol was tested with the aim of drawing out local anesthesia without supplementary anesthesia. This possibility is especially interesting for patients with restriction of maximum recommended dose of LA or vasoconstrictor due to pathological conditions (e.g. heart disease). We used 2% lidocaine hydrochloride with epinephrine for sensitive, motor and proprioceptive blockade of the sciatic nerve in rats (Truant, 1958). Hyaluronidase 75 UTR was injected 30 minutes after the beginning of the anesthesia (before the recovery of the sensory function), using the contralateral limb as control (injection of LA plus the H vehicle solvent). The duration of the sensitive blockade was evaluated through the absence of the paw withdrawal reflex, using an analgesymeter. The motor blockade was evaluated by the duration of claudication (complete absence of extensor postural thrust) and by the absence of the paw stretching reflex, while the proprioceptive blockade was evaluated by the absence of hopping and tactile placing response (Thalhammer et al., 1995). Histological changes induced by H were analyzed 1h, 24h, 48h, and 72 h after the injection in the following groups: (1) Sham; (2) LA + H; (3) LA + H solvent (solv) and (4) Solv + Solv. We concluded that H draws out local anesthesia when injected before the recovery of the sciatic nerve blockade in the rat. In all groups studied, with the exception of the Sham, there was an inflammatory reaction after the injections. Inflammation was more intense after H injection, showing signs of regression after 72 hours. It is possible that the mechanism of action of H involves disorganization of the connective tissue, thus facilitating the diffusion of the residual anesthetic solution to the nerve.
60

Influência da adição de células-tronco mesenquimais derivadas de tecido adiposo associadas a conduto de fibrina na regeneração de nervo periférico em modelo experimental de ratos / Influence of the addition of adipose derived stem cell in fibrin conduit for peripheral nerve regeneration in a rat model

Longo, Marco Vinicius Losso 06 November 2015 (has links)
INTRODUÇÃO: O tratamento padrão para lesões de nervo periférico que não podem ser suturados primariamente é a enxertia de nervo autólogo. Esse método, porém, carece de resultados satisfatórios e impõe algumas limitações técnicas e complicações. Várias opções já foram estudadas como alternativas ao enxerto de nervo, porém ainda não há conduto biológico ou sintético disponível para uso clínico que tenha a mesma capacidade regenerativa do enxerto de nervo autólogo. Os avanços em cultura celular e o maior entendimento dos mecanismos moleculares e celulares da regeneração nervosa levaram ao uso de células promotoras de regeneração associado aos condutos na tentativa de melhorar os resultados da reconstrução nervosa. Vários estudos demonstraram que o uso de célulastronco derivadas de tecido adiposo (ADSC) em condutos aloplásticos potencializa a regeneração neural. No entanto, nenhum estudo até hoje comparou a adição de ADSC indiferenciadas em conduto aloplástico ao tratamento padrão com autoenxerto. Esse estudo tem como objetivo avaliar a influência da adição de células-tronco mesenquimais derivadas de tecido adiposo em conduto de fibrina na regeneração de nervo periférico e comparar com enxertia de nervo autógeno em modelo experimental de ratos. MÉTODO: Em um modelo de lesão de nervo ciático (defeito de 10 mm) foram avaliados 30 ratos Wistar divididos em 3 grupos. O defeito de nervo foi reconstruído usando conduto de fibrina (Grupo Conduto, n=10), conduto de fibrina acrescido de ADSC (Grupo ADSC, n=10) e autoenxerto do nervo (Grupo Autoenxerto, n=10). A avaliação funcional dos ratos foi realizada com o teste de marcha (walking track analysis) com 4, 8 e 12 semanas e o índice de função ciática (IFC) foi determinado. Após 12 semanas, o peso do músculo tríceps sural foi avaliado. Segmentos dos nervos regenerados também foram coletados para análises histológicas como densidade axonal e diâmetro médio das fibras. RESULTADOS: O grupo Conduto mostrou recuperação funcional no teste da marcha após a reconstrução do nervo, porém com resultados inferiores aos outros dois grupos. O grupo ADSC mostrou recuperação intermediária e o grupo Autoenxerto obteve os melhores resultados (IFC com 12 semanas de -53,3±.3 vs -44,7±3 vs - 35,6±2, respectivamente, p < 0,001). A relação de peso do músculo tríceps sural no grupo Conduto foi de 41,1±3%, no grupo ADSC de 53,3±4% e no grupo Autoenxerto de 71,0 ± 4% (p < 0,001). Na avaliação histológica, o grupo Conduto mostrou densidade axonal de 39,8±3 axônios/10.995?m2 e diâmetro médio das fibras de 3,9 ± 0?m2, o grupo ADSC densidade axonal de 58,8 ± 3 axônios/10.995um2 e diâmetro médio das fibras de 4,9 ± 1um2 e o grupo Autoenxerto densidade axonal de 67,1±2 axônios/10.995?m2 e diâmetro médio das fibras de 8,9±1um2 (p < 0,001). CONCLUSÃO: A adição de células-tronco mesenquimais derivadas de tecido adiposo (ADSC) em conduto de fibrina na regeneração de nervo periférico, em modelo experimental de ratos, mostrou recuperação funcional e regeneração histológica estatisticamente mais significativa comparada à reconstrução somente com conduto de fibrina, porém ainda aquém dos resultados obtidos com enxertia de nervo autógeno / Introduction: The standard treatment for peripheral nerve injuries that cannot be primarily sutured is nerve autograft. But this method lacks satisfactory results and imposes some technical limitations and complications. Several options have been studied as alternatives to nerve autografting, but there is no biological or synthetic conduit available for clinical use that provides the same regenerative capacity of nerve autograft. Advances in cell culture and understanding of nerve regeneration mechanisms led to the use of regeneration-inducing cells in association with conduits, in an attempt to improve the reconstruction results. Several studies have shown that the use of adipose derived stem cells (ADSC) into conduits enhances neural regeneration. However, there is no study that compared the addition of undifferentiated ADSC in alloplastic conduit to standard treatment with autograft. This study evaluated the influence of the addition of adipose derived stem cell in fibrin conduit for peripheral nerve regeneration in comparison to the nerve autograft, in a rat model. Method: A sciatic nerve injury model (10-mm defect) was performed in 30 Wistar rats, which were divided into 3 groups. Nerve defect was reconstructed using fibrin conduit (Conduit group, n=10), fibrin conduit filled with ADSC (ADSC group, n = 10) and nerve autograft, (Autograft group, n=10). The walking behavior was measured by footprint analysis at 4, 8, and 12 weeks and sciatic function index (SFI) was determined. After 12 weeks, the triceps surae muscle weight was evaluated and histological analysis was performed to evaluate the regenerated nerve and measured axonal density and fibers diameter average. Results: The Conduit group showed less improvement in walking behavior compared to ADSC group and Autograft group (SFI at 12 weeks, - 53.3 ± .3 vs -44.7 ± 3 vs -35.6 ± 2 respectively, p< 0.001). The triceps surae muscle weight ratio of the fibrin conduit group was 41.1± 3%, ADSC group was 53.3 ± 4%, and Autograft group 71.0 ± 4% (p < 0.001). In histological evaluation, the Conduit group showed axonal density of 39.8±3 axons/10995um2 and fiber diameter average of 3.9±0 ?m2, the ADSC group had axonal density of 58.8 ± 3 axons/10995 um2 and fiber diameter average of 4.9±1?m2 and axon density of Autograft group was 67.1±2 axons/10995 um2 and fiber diameter average was 8.9±1?m2 (p < 0.001). Conclusion: The addition of adipose derived stem cells (ADSC) into fibrin conduit used for nerve reconstruction following peripheral nerve injury in the rat model, showed better functional recovery and better histological regeneration compared to reconstruction with fibrin conduit without ADSC. However, the functional recovery in the ADSC group was worse than that in nerve Autograft group and the nerve repair with the ADSC-fibrin conduit has less myelinated fibers when compared to the repair with nerve autograf

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