Orientador: Sara Teresinha Olalla Saad / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-22T11:44:55Z (GMT). No. of bitstreams: 1 Ribeiro_ThiagoBorsoi_D.pdf: 4887111 bytes, checksum: 5ba29a0d383225adef5209fb35a27d81 (MD5) Previous issue date: 2013 / Resumo: A avulsão de raízes motoras, na interface do sistema nervoso central e periférico, já bem descrito na literatura, promove uma significativa perda sináptica com degeneração de cerca de 80% dos motoneurônios afetados. Não existem estratégias eficazes que propiciem uma reversão ou amenização deste quadro, mas alguns estudos já mostram que o passo fundamental é preservar os motoneurônios afetados. Pesquisas em diferentes áreas com células-tronco (CT) adultas estão sendo realizadas nos últimos anos e apresentam resultados promissores para a medicina regenerativa. Investigações recentes têm apontado para diferentes fontes de CT em tecidos adultos tais como de medula óssea, de sangue de cordão umbilical, tecido muscular, tecido nervoso, líquido amniótico entre outras. De modo geral, estas células apresentam como características principais a capacidade de proliferação e a diferenciação para outros tipos celulares. Entretanto, os principais problemas para o uso clínico das CT adultas são: i) pequena quantidade de células multipotentes, ii) o controle da diferenciação, iii) insuficiência no número de células viáveis e iiii) difícil obtenção. Como alternativa às dificuldades anteriormente citadas, o tecido adiposo tem sido foco de intensos estudos, pois este tecido possui rica fonte de células pluripotentes, além de apresentarem características positivas como fácil acesso ao tecido adiposo subcutâneo, obtenção em quantidade abundante e processo de isolamento celular relativamente simples. Apesar deste tecido apresentar organização complexa, é na fração celular do estroma vascular que se encontra uma rica população de células pluripotentes. Dados de literatura demonstram que as células mesenquimais derivadas de tecido adiposo (AT-MSC - Células mesenquimais de tecido adiposo), mediante incubação com meios de cultura variados, diferenciam-se em adipócitos, osteócitos, mioblastos, hepatócitos, células vasculares entre outras. A diferenciação de AT-MSC em células neuronais ainda é alvo de discussões e críticas na literatura, pois não há protocolos estabelecidos que induzam a diferenciação em células neuronais funcionais absolutas. Ainda, recentes estudos atribuem um potencial neuroprotetor e uma capacidade imunomodulatória à produção de fatores neurotróficos e a produção de fatores solúveis pelas AT-MSCs, constituindo talvez o principal mecanismo de ação destas células in vivo. O xenotransplante também é alvo de criticas de diversos trabalhos. Células humanas em modelo animal têm sido usadas constantemente em diversos trabalhos e o uso ou não de imunossupressores é um dos motivos de questionamento dos resultados, uma vez que sistemas imunológicos diferentes podem causar reações imunológicas não pretendidas nos estudos e, consequentemente, os resultados não seriam confiáveis. Entretanto, artigos de revisões x bibliográficas demonstram que diversos estudos envolvendo células-tronco mesenquimais e modelos animais têm resultados promissores e corroboram entre si. Com objetivo de investigar a ação de células-troncos de tecido adiposo de lipoaspirado humano em modelo animal, o presente trabalho propôs analisar a capacidade de sobrevivência das AT-MSCs humanas no modelo de avulsão da raiz ventral de ratos, bem como sua capacidade de neuroproteção dos motoneurônios lesionados e sua competência de imunossupressão no período de 2 semanas pós lesão (período agudo). Análise da dinâmica das sinapses, da reação astroglial e microglial e da reação de linfócitos T tiveram o objetivo de identificar condições que promovessem a sobrevivência e regeneração dos motoneurônios axotomizados assim como a capacidade de atuação das células humanas em ratos. Deste modo, foi observado que o tratamento com as AT-MSC humanas tiveram efeito neuroprotetor, uma vez que houve aumento significativo de sobrevivência neuronal e promoveram a estabilidade sináptica. As células humanas também tiveram ação imunomodulatória, reduzindo a astrogliose reativa e ativação microglial, bem como inibiu a atividade de linfócitos T. Pode-se dizer que no modelo a ação das células-tronco mesenquimais humanas ocorre semelhante ao de transplantes alogênicos em modelos animais / Abstract: It is well described in the literature that avulsion motor at the interface of the central and peripheral nervous system, promotes a significant loss of synaptic degeneration and 80% of motor neurons death. There is no effective strategies that favor a reversal or mitigation of this framework, but some studies have shown that the key step is to preserve motor neurons affected. Researches in different areas with stem cell (CT) adults are being undertaken in recent years and show promising results for regenerative medicine. Recent investigations have pointed to different sources of CT in adult tissues such as bone marrow, umbilical cord blood, brain, muscle tissue, amniotic fluid, among others. Generally, these cells have as main characteristics capacity for proliferation and differentiation to other cell types. However, the main problems for the clinical use of adult SC are: i) small amount of multipotent cells, ii) differentiation control, iii) low number of viable cells and iiii) difficulty to obtain. As an alternative to the difficulties mentioned above, adipose tissue has been the focus of intense study, because this tissue has a rich source of stem cells, in addition to having positive characteristics such as easy access to subcutaneous adipose tissue, obtained in abundant quantities and isolation process relatively simple. Despite the complex tissue organization, the stromal vascular fraction is rich of pluripotent population cells. Literature data show that stromal cells derived from adipose tissue (AT-MSC-adipose tissue mesenchymal stem cells) can differentiate by incubation with various culture media into adipocytes, osteocytes, myoblasts, hepatocytes, vascular cells, among others. The AT-MSC differentiation into neuronal cells is still subject of discussion and criticism in literature, since no established protocol has induced differentiation into function neuronal cells. Still, many studies attribute a potential neuroprotective and immunomodulatory capacity for the production's AT-MSC of neurotrophic factors and the soluble factors, constituting perhaps the main mechanism of action of these cells in vivo. Xenotransplantation is the target of criticism of many studies. Human cells constantly used in animal models have been used in several works and the use of immunosuppressants or not is subject to questioning of the results, since different immune systems can cause unwanted immune reactions in studies and, consequently, the results would not be reliable. Literature reviews show that several studies involving mesenchymal stem cells and animal models have shown promising results and corroborate each other. xii To investigate the action of stem cells from human adipose tissue lipoaspirate animal model, this study proposes to analyse the survivability of the human AT-MSC in ventral root avulsion model in rats as well as its ability to neuroprotection in moto neurons and their competence in the period of immunosuppression 2 weeks post injury (acute period). To identify conditions that promote the survival and regeneration of axotomized motoneurons as well as the capacity for action of human cells in mice, synapses dynamic analysis, astroglial and microglial reaction and reaction of T lymphocytes was examined. Thus, it was observed that treatment with AT-MSC had neuroprotective effect, since there was a significant increase in neuronal survival and the AT-MSC human promoted synaptic stability. Human cells also have immunomodulatory action, reducing reactive astrogliosis and microglial activation and inhibited the activity of T lymphocytes. It is possible that the model action of human mesenchymal stem cells is similar to that of allogeneic / Doutorado / Biologia Estrutural, Celular, Molecular e do Desenvolvimento / Doutor em Fisiopatologia Medica

Para a execução deste trabalho, valemo-nos de trinta fetos de bovinos azebuados, fêmeas. Após o processo de conservação e de redução das peças, realizamos sua dissecção, com auxílio de instrumentos de cirurgia oftálmica e lupa circular de luz fria. Priorizamos a observação da origem do tronco do nervo pudendo registrando-a, maus freqüentem ente (76,7%) em relação ao segundo, terceiro e quarto nervos sacrais, destacando como contribuição mais conspícua, a que se refere ao terceiro nervo sacra (90%). Especificamos também as contribuições dos ramos ventrais dos nervos sacrais destinadas a cada um dos ramos, registrando participação mais freqüentemente do terceiro e quartos nervos, isto é: cutâneo proximal (56,7% à direita e 53,3% à esquerda), cutâneo distal (70% à direita e 56,7% à esquerda) e nervo pudendo (propriamente dito - 76,7% à direita e 73,3% à esquerda), considerandoo-os enquanto contidos na cavidade pélvica. Registramos o número de ramos representativos dos ramos cutâneos proximal e dista], sendo respectivamente encontrado em apresentação única à direita (63,3% - 96,7%) e à esquerda (66,7% - 83,3%); dupla à direita (23,3% - 3,3%) e à esquerda (23,3% - 16,7%) e tripla, exclusivamente para o ramo cutâneo proximal à esquerda (3,3%). Observamos também a emergência desses ramos da cavidade pélvica, representada para o ramo cutâneo proximal mais freqüentemente através do forame isquiático menor à direita (16,7%) e à esquerda (16,7%) oou perfurando o ligamento sacrotuberal largo à direita (46,7%) e à esquerda (50%) e, para o ramo cutâneo distal pela fossa ísquio-retal para ambos os antímeros (100%). 0 nervo pudendo (propriamente dito), no terço final da cavidade pélvica, origina sempre o ramo dorsal do clitóris e o ramo mamário (100%). Registramos ainda, ocorrência de ramo conectivo (\"anastomose\") entre um pequeno ramo que adentra a cavidade pélvica pela porção cranial do forame isquiático menor e o nervo pudendo (propriamente dito) ou um de seus ramos - o nervo perineal profundo (63,3%). Os resultados obtidos em relação ao comportamento do nervo pudendo em fetos de bovinos azebuados, fêmeas, de modo geral, não mostram discordância com os correspondentes dados obtidos na literatura consultada, referentes a bovinos de origem européia. / In order to perform this research, 30 female fetuses from crossbred zebus were used. After applying the process of conservation and reduction of the pieces, dissections were made by using ophthalmic surgical instruments and circular magnifying glass fitted with cold lamp. Priority was given to the observation of the origin of the pudendum nerve trunk registering it, more frequently, in relation to the second, third and fourth sacral nerves (76.7%), emphasizing it as the most remarkable contribution, the one that refers to the third sacral nerve (90%). While enclosed in the pelvic cavity, we considered contributions of the ventral branches of the sacral nerves, specifically destinated to each of the branches, registering more abundantly participation of the third and fourth nerves, that is: proximal cutaneous (56.7% to the right and 53.3% to the left), distal cutaneous (70% to the right and 56.7% to the left) and pudendum nerve (properly speaking - 76.7% to the right and 73.3% to the left). We registered the number of branches representative of the proximal cutaneous and of the distal cutaneous, being respectively found in the unique appearance to the right si de (63.3% and 96.7%) and to the left (66.7% and 83.3%); double to the right (23.3% and 3.3.%) and to the left (23.3% and 16.7%), and triple, exclusively to the proximal cutaneous branch to the left (3.3%). The emergence of these branches from the pelvic cavity was also observed, represented to the proximal cutaneous branch more often through the minor ischiatic foramen to the right (16.7%) and to the left (16.7%) or perforating the large sacrotuberal ligament to the right (46.7%) and to the left (50%) and, to the distal cutaneous branch through ischiorectal fossa to both antimeres (100%). The pudendum nerve (properly speaking), in the final one-third of the pelvic cavity, always originates the dorsal branch of the clitoris and the mammary branch (100%). The occurrence of the comiective branch (\"anastomosis\") between a small branch entering into the pelvic cavity through the cranial portion of the minor ischiatic foramen (properly speaking) and the pudendum nerve or one of its branches - the deep pudendum nerve was also observed (63.3%). The results of the behavior of the pudendum nerve found in female fetuses of the crossbred zebu cattle did not differ from those of the Europen cattle, as described in the literature.

Ces dernières années, il est apparu que les espèces réactives de l'oxygène (ROS) ne sont pas seulement des substances délétères qui induisent des dommages de molécules biologiques, mais qu’elles sont également impliquées dans la signalisation cellulaire. Des niveaux contrôlés de H2O2 sont en particulier impliqués dans le processus de régénération chez différentes espèces. Nous avons donc étudié la régulation de la signalisation de H2O2 au cours de régénération de la nageoire caudale chez le poisson zèbre adulte. Nous avons montré que les nerfs contrôlent les niveaux de H2O2 à la fois dans les tissus normaux et après blessure; ce processus est médié par les cellules de Schwann qui expriment Shh. En plus, H2O2 stimule la croissance des nerfs, ce qui suggère la présence d'une boucle de rétrocontrôle positif.Les niveaux redox sont très dynamiques non seulement lors de la régénération, mais aussi au coursdu développement. Nous avons ensuite examiné le rôle de H2O2 pendant la morphogenèse et plusprécisément, son impact sur la croissance axonale et sa relation avec la signalisation Shh. Nous avons constaté que la réduction des niveaux de H2O2, normalement très élevé au cours de la morphogenèse, altère les projections axonales et que cet effet peut être sauvé par l'activation de la voie de signalisation de Shh.Les cibles de la signalisation redox comprennent des protéines dont l'activité est dépendante d'une cystéine, car l'état d'oxydation de cet acide aminé peut être modifié par les niveaux de H2O2. Le processus de S-acylation, qui est très important pour le processus de croissance des projections axonales et pour la voie de signalisation de Shh, consiste en la fixation covalente d'un acide gras, souvent le palmitate, au group sulfurique d’une cysteine et il est donc une cible potentielle de signalisation de ROS. Nous avons mis en évidence une corrélation entre le niveau de palmitoylationd’une protéine et les niveaux de H2O2 dans la cellule. La pertinence de cette observation estactuellement testée in vivo. / In the recent years it is becoming evident that reactive oxygen species (ROS) are not only deleterious compounds that induce damage of biological molecules, but are also important molecules that can mediate different signaling pathways. Controlled ROS, and in particular H2O2, levels have been found to be involved in the regenerative process of different species. We then focused on the regulation of H2O2 signaling during regeneration of the adult zebrafish caudal finand we showed that nerves control H2O2 levels both in normal tissue and after lesioning; this process is mediated by Schwann cells, through Shh signaling. In addition, there is also a reciprocal action of H2O2 on nerve growth, suggesting the presence of a positive feedback loop.Redox levels are highly dynamic not only during regeneration, but also during development. We then looked at the role of H2O2 during morphogenesis and more specifically, its impact on axonal growth and its relationship with Shh signaling. We found that reduction of H2O2 levels, normally very high during morphogenesis, impairs axon projections and that this effect can be rescued by the activation of Shh signaling. Moreover, we found that different redox levels modify the intracellulardistribution of Shh protein and also its extracellular availability. These results further strengthen the relationship between H2O2 and Shh signaling pathways.It is widely accepted that targets of redox signaling include proteins whose activity is dependent on an active cysteine because the oxidative status of this amino acid can be modified by H2O2 levels.The process of S-acylation, which is very important for both the processes of axonal projections growth and Shh signaling, consists in the covalent attachment of a fatty acid, often palmitate, to a cysteine sulphur and it is then a possible target of ROS signaling. We asked whether a relationship between H2O2 levels and protein S-palmitoylation could exist and we found that augmentation of H2O2 levels downregulates the S-palmitoylation process. The relevance of this observation iscurrently being tested in vivo.

Orientadores: Alan Roger dos Santos Silva, Ana Lúcia Carrinho Ayroza Rangel / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-26T10:30:04Z (GMT). No. of bitstreams: 1 Iachinski_TatianaSantosAssumpcao_D.pdf: 1245874 bytes, checksum: 0e426f4d5b6b5c707e92933df790258a (MD5) Previous issue date: 2014 / Resumo: O tratamento do câncer pode provocar efeitos colaterais que limitam a efetividade da terapia e ter grande impacto na qualidade de vida do paciente. A dor orofacial em pacientes oncológicos é comum e pode estar relacionada à quimioterapia. A neurotoxicidade periférica e a dor neuropática são complicações de diversos agentes quimioterápicos, como a Oxaliplatina, que apresenta alta incidência de efeitos colaterais por toxicidade aguda e crônica. O objetivo deste estudo foi pesquisar as manifestações sensitivas e motoras orofaciais causadas pela neurotoxicidade do esquema quimioterápico FOLFOX 4. Na avaliação clínica prospectiva, foram avaliados 23 pacientes com câncer de cólon e reto, submetidos ao esquema quimioterápico FOLFOX 4 - FOL: Ácido Folínico (Leucovorina), F: Fluorouracil (5-FU), OX: Oxaliplatina. Os pacientes foram avaliados em quatro momentos da quimioterapia: no ciclo 1, entre o ciclo 2 e 3, entre o ciclo 6 e 8 e no último ciclo (12). Exame clínico e questionário foram aplicados para pesquisar ocorrência e as características clínicas da neuropatia periférica, incluindo: dor orofacial, parestesia perioral, disgeusia, disfagia, disartria, câimbra nos músculos mastigatórios, perda de sensibilidade tátil, disestesia, e a ocorrência de odontalgia neuropática. O acompanhamento durante os ciclos da quimioterapia buscou avaliar fatores desencadeantes, de piora e melhora, para intervenções dirigidas à dor. A manifestação da neurotoxicidade orofacial ocorreu no sintoma de parestesia em lábio, língua ou perioral, em 13% dos pacientes, e disgeusia, em 57% dos pacientes. Dor neuropática em face, boca ou dentes não foram detectadas na pesquisa. Os sintomas foram transitórios, caracterizando uma toxicidade aguda. Pode-se concluir que o esquema quimioterápico FOLFOX 4 está associado a neurotoxicidades orofaciais transitórias como parestesia e disgeusia, sugerindo neuropatia aguda. Contudo, o protocolo de tratamento em questão não desencadeou dor orofacial / Abstract: The treatment of cancer can produce side effects, which are dose-limiting and provoke a great impact on patient's quality of life. Orofacial pain often affects cancer patients, and it may be related to chemotherapy. The peripheral neurotoxicity and the neuropathic pain are complications of chemotherapeutic agents, such as oxaliplatin, which leads to a high incidence of acute and chronic side effects. The aim of this study was to investigate the orofacial sensory and motor manifestations of neurotoxicity induced by FOLFOX 4 chemotherapy in the treatment of colon cancer. Twenty-three patients were enrolled in this clinical prospective study, treated by FOLFOX 4 - FOL: Folic Acid (Leucovorin), F: Fluorouracil (5-FU), OX: Oxaliplatin (Eloxatin). The assessment was conducted in four stages of chemotherapy: cycle 1, between cycle 2 and 3, between cycle 6 and 8, and in the last cycle (12). The symptoms of the peripheral neuropathy manifestation were investigated using a questionnaire and clinical examination, in order to determine the occurrence and the clinical characteristics of the following symptoms: orofacial pain, perioral paresthesia, dysgeusia, dysphagia, dysarthria, cramps, loss of tactile sensitivity, dysesthesia, and the neuropathic dental pain. The monitoring during cycles of chemotherapy aimed to identify trigger points, worsening and improvement factors for interventions oriented toward the pain. The manifestation of neurotoxicity occurred as paresthesia in lips, tongue or perioral region, in 13% of patients, while dysgeusia affected 57% of the patients during the treatment. In this research, neuropathic pain in the face, oral region or teeth was not detected. The manifested symptoms were transient, remaining about three days, suggesting an acute toxicity. This study demonstrated that FOLFOX 4 is related to oral symptoms, such as paresthesia and dysgeusia, which decreased at the end of treatment, charactering acute neuropathy. Conversely, this protocol did not triggered orofacial pain / Doutorado / Estomatologia / Doutora em Estomatopatologia

The neurotrophic factor neurturin is required for normal cholinergic innervation of adult mouse heart and bradycardic responses to vagal stimulation. Our goals were to determine effects of neurturin deletion on development of cardiac chronotropic and dromotropic functions, vagal baroreflex response, and cholinergic nerve density in nodal regions of postnatal mice. Experiments were performed on postnatal C57BL/6 wild-type (WT) and neurturin knockout (KO) mice. Serial electrocardiograms were recorded noninvasively from conscious pups using an ECGenie apparatus. Mice were treated with atenolol to evaluate and block sympathetic effects on heart rate (HR) and phenylephrine (PE) to stimulate the baroreflex. Immunohistochemistry was used to label cholinergic nerves in paraffin sections. WT and KO mice showed similar age-dependent increases in HR and decreases in PR interval between postnatal days (P) 2.5 and 21. Treatment with atenolol reduced HR significantly in WT and KO pups at P7.5. PE caused a reflex bradycardia that was significantly smaller in KO pups. Cholinergic nerve density was significantly less in nodal regions of P7.5 KO mice. We conclude that cholinergic nerves have minimal influence on developmental changes in HR and PR, QRS, and QTc intervals in mouse pups. However, cholinergic nerves mediate reflex bradycardia by 1 week postnatally. Deletion of neurturin impairs cholinergic innervation of the heart and the vagal efferent component of the baroreflex early during postnatal development.

6-hydroxydopa (6-OHDOPA) was synthesized with the expectation that it would be able to cross the blood-brain barrier to be enzymatically decarboxylated to 6-hydroxydopamine (6-OHDA), the newly discovered neurotoxin for noradrenergic and dopaminergic neurons. In part, 6-OHDOPA fulfilled these criteria. When administered experimentally to rodents, 6-OHDOPA destroyed peripheral sympathetic noradrenergic nerves and did exert neurotoxicity to noradrenergic nerves in brain—in large part, from its conversion to 6-OHDA. However, the efficacy of 6-OHDOPA was less than that of 6-OHDA; also, 6-OHDOPA was relatively selective for noradrenergic neurons; near-lethal doses of 6-OHDOPA were required to damage dopaminergic nerves; and ultimately, 6-OHDOPA was found to be an agonist at AMPA receptors, thus accounting for more non-specificity. Nevertheless, 6-OHDOPA was found to be a particularly valuable tool in uncovering processes and mechanisms associated with noradrenergic nerve regeneration and sprouting, particularly when administered to perinatal rodents. Also, 6-OHDOPA was a good tool for selective mapping of noradrenergic nerve tracts in brain, since dopaminergic tracts were unaffected and did not interfere with the histofluorescent methodology used for this purpose in the early 1970s. As an experimental research tool, 6-OHDOPA was valuable in a short time-window, but its utility is largely limited because of newer research technologies that provide better means today for nerve tract mapping, and for experimental approaches engaged toward study of processes and mechanisms attending nerve regeneration. AMPA actions of 6-OHDOPA have not been extensively studied, so this avenue may enliven use of 6-OHDOPA in the future.

Application of substance P (SP) to intracardiac neurons of the guinea pig causes slow depolarization and increases neuronal excitability. The present study was done to determine the influence of SP on fast excitatory responses of intracardiac neurons to ACh. Intracellular recording methods were used to measure responses of intracardiac neurons in whole mount preparations of atrial ganglionated nerve plexus from guinea pig hearts. Local pressure ejection of 100 μM SP (1 s) from a glass micropipette caused slow depolarization of all neurons (n = 38) and triggered action potential generation in 47% of the cells tested. Bath application of SP (0.5-100 μM) caused a dose-dependent depolarization of intracardiac neurons but rarely evoked action potentials, even at the highest concentration. However, such treatment with SP enhanced nicotinic responses evoked by local pressure ejections of ACh (10 mM, 10- to 100-ms duration) in 77% of intracardiac neurons studied (n = 52). A significant increase in amplitude of ACh-evoked fast depolarization occurred during treatment with 0.5 μM SP (13.0 ± 1.8 mV for control vs. 17.7 ± 1.9 mV with SP present, n = 7, P = 0.019). At higher concentrations of SP, enhancement of the response to ACh resulted mainly in action potential generation. However, responses to ACh were attenuated by SP in 15% of the intracardiac neurons studied. This attenuation occurred primarily during exposure to 10 and 100 μM SP and was manifest as a reduction in amplitude of nicotinic fast depolarization or inhibition of ACh-evoked action potentials. These findings support the conclusion that SP could function as a neuromodulator and neurotransmitter in intracardiac ganglia of the guinea pig.

Indiana University-Purdue University Indianapolis (IUPUI) / Although peripheral motoneurons are phenotypically endowed with robust regenerative capacity, functional recovery is often suboptimal following peripheral nerve injury (PNI). Research to date indicates that the greatest success in achieving full functional recovery will require the use of a combinatorial approach that can simultaneously target different aspects of the post-injury response. In general, the concept of a combinatorial approach to neural repair has been established in the scientific literature but has yet to be successfully applied in the clinical situation. Emerging evidence from animal studies supports the use of electrical stimulation (ES) and testosterone as one type of combinatorial treatment after crush injury to the facial nerve (CN VII). With the facial nerve injury model, we have previously demonstrated that ES and testosterone target different stages of the regeneration process and enhance functional recovery after facial nerve crush injury. What is currently unknown, but critical to determine, is the impact of a combinatorial treatment strategy of ES and testosterone on functional recovery after crush injury to the sciatic nerve, a mixed sensory and motor spinal nerve which is one of the most serious PNI clinical problems. The results of the present study indicate that either treatment alone or in combination positively impact motor recovery. With regard to molecular effects,single and combinatorial treatments differentially alter the expression of regeneration-associated genes following sciatic nerve crush injury relative to facial nerve injury. Thus, our data indicate that not all injuries equally respond to treatment. Furthermore, the results support the importance of treatment strategy development in an injury-dependent manner and based upon the functional characteristics of spinal vs. cranial nerves.

No description available.

Na primeira parte deste estudo, foram dissecados 30 polos superiores tireoideanos, de 15 cadáveres frescos, com o intuito de se identificar o ramo externo do nervo laríngeo superior (RELS) e analisar as suas relações anatômicas com o pedículo superior da glândula tireóide. Obedecendo a uma classificação eminentemente anátomo-cirúrgica, 1 nervo (3%) não foi localizado, 18 (60%) eram do Tipo 1 (cruzando os vasos tireoideanos superiores acima de 1 cm de um plano horizontal que passava pela borda do polo superior tireoideano), 5 (17%) eram do Tipo 2a (nervo a menos de 1 cm acima do plano acima descrito) e 6 (20%) eram do tipo 2b (nervo abaixo do plano). Esta última configuração anatômica foi considerada de alto risco de lesão iatrogênica durante uma hipotética tireoidectomia. A seguir, foi executado um estudo clínico, prospectivo e randomizado. Setenta e seis doentes, após uma avaliação fonoaudiológica completa pré-operatória, foram divididos em tres grupos. No Grupo 1, o polo superior foi dissecado pelo Autor com lupa, pesquisando-se o RELS, após a secção dos músculos pré-tireoideanos, por meio de um neuro-estimulador e observando-se a consequente contração do músculo crico-tireoídeo (MCf) no próprio campo operatório. No Grupo 2, o polo superior tireoideano foi dissecado por Médicos-Residentes de 20. Ano de Cirurgia Geral, estagiando na Disciplina de Cirurgia de Cabeça e Pescoço do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (DCCP-HC FMUSP), sem qualquer tentativa para se individualizar o RELS. Os indivíduos do Grupo 3 foram operados obedecendo à mesma técnica descrita no grupo anterior, pelo Autor. No período pós-operatório, foi repetida a avaliação fonoaudiológica e realizada uma eletromiografia de ambos os MCT. Os doentes que tiveram uma lesão completa do RELS, comprovada pela ausência de atividade elétrica do MCT, sofreram novas avaliações fonoaudiológica e eletromiográfica tardias, 6 meses após a cirurgia. Nenhum caso do Grupo 1 apresentou lesão completa do RELS. No Grupo 2, 28% dos pacientes exibiram esta lesão, que foi definitiva em 57%. No Grupo 3, constataram-se lesões totais em 12% dos doentes; nenhuma das lesões analisadas tardiamente neste grupo foi definitiva. Quando comparados com os nervos não dissecados, houve um aumento estatisticamente significativo de lesões completas nos Grupos 2 (p=O,0002776) e 3 (p=O,0346393), enquanto que não houve diferença nos doentes do Grupo 1. A avaliação fonoaudiológica revelou uma melhora nos parâmetros dos casos do Grupo 1, mormente aqueles relacionados com a respiração. Observou-se uma deterioração da performance vocal nos doentes do Grupo 2, que persistiu, em parte, na avaliação fonoaudiológica tardia. Já no Grupo 3 foi marcante uma piora estatisticamente significativa nas frequências mais altas e uma redução acentuada na extensão vocal, que foram atribuídas a lesões parciais do RELS, não detectadas pela avaliação eletromiográfica. Concluiu-se que a única forma eficaz de se prevenir uma lesão iatrogênica do RELS durante uma tireoidectomia foi a sua pesquisa sistemática e objetiva na região do polo superior, com O auxílio de um neuro-estimulador. / In the first part of this study, the external branch of the superior laryngeal nerve (RELS) was dissected in the region of 30 superior thyroid poles, in 15 fresh cadavers, with special attention for its anatomical relationship with the superior thyroid vessels. Four different kinds of nerves were found: Not localized - 1 (3%) nerve; Type 1 (crossing the superior thyroid vessels more than 1cm above a horizontal plane located at the upper limit of the superior thyroid pole) - 18 (60%); Type 2a (nerve situated less than 1 cm above the plane) - 5 (17%); Type 2b (nerve below the plane) - 6 (20%). This last relationship was considered to be \"high risk\", regarding an iatrogenic lesion during a hypothetical thyroidectomy. Then, a prospective randomized clinical study was undertaken. Seventy-six patients, after being submitted to a complete phonoaudiological evaluation, were divided in three groups. In Group 1, the superior thyroid pole was dissected by the Author with a loupe, searching the RELS with a nerve stimulator, after dividing the strap muscles to gain better exposure. The identification of the nerve was considered to be positive when a contraction of the cricothyroid muscle (MCT) was obtained. In Group 2, the superior thyroid pole was operated on by 2nd Year General Surgery Residents, training during a I-rnonth period at the Department of Head and Neck Surgery of Hospital das Clínicas of the University of São Paulo Medical School (DCCP-HC FMUSP), without any attempt to identify the RELS. In Group 3, the patients were operated on by the Author, according to the same technique described for the Group 2. In the postoperative period, the complete phonoaudiological evaluation was repeated and an electromiography of both MCTs was performed. Those cases who showed a complete lesion of the RELS, which was evident by the absence of any electrical activity of the MCT, underwent again both phonoaudiological and electromiographic evaluations, 6 months after the surgery. No patient in Group 1 showed any complete lesion of the RELS. In Group 2, 28% of the cases suffered this lesion, which was definitive in 57%. In Group 3, 12% of the patients had a complete paralysis of the nerve; none of the two lesions analyzed after 6 months (67%) proved to be definitive. A comparison of the three groups was established with the non-dissected nerves. A significant statistical difference was obtained in the Groups 2 (p=0.0002776) and 3 (p=0.00346393), clearly demonstrating an increased risk of lesion in these groups. No difference was observed between Group 1 and the non-dissected nerves group. An actual improvement in the vocal performance was noted in Goup 1, especially regarding respiratory characteristics. On the other hand, the vocal performance worsened in Group 2 patients, and this deterioration persisted, in part, also during the late evaluations. ln Group 3, there was a marked lowering of the highest frequencies, associated with a profound reduction in the vocal extension. These features were attributed to partial RELS lesions, which could not be detected by the electromiography. ln conclusion, the only effective way to prevent an iatrogenic lesion of the RELS during a thyroidectomy was, in this study, an objective and meticulous search of the nerve near the superior thyroid pole, using a nerve stimulator.