Relationship between oxidative stress and inflammation in peripheral and cerebral system of oxonate-induced hyperuricemic rats

To study what kind of role uric acid play on the relationship between oxidative Stress and inflammation in peripheral and cerebral system of oxonate-induced hyperuricemic rats. Twenty-six eight male Wistar rats were divided into two groups randomly. Potassium oxonate was used to establish hyperuricemic model for four weeks. In 2nd and 4th week, uric acid (UA) level, total superoxide dismutase (T-SOD), Gu,Zn-SOD activity and interleukin-1beta (IL-1ß) concentration in serum were determined respectively. In 4th week, one hour after last PO treatment, five rats of every group were given Evans Blue to test blood-brain barrier (BBB) permeability. Other brains were obtained to analysis T-SOD, Gu,Zn-SOD activity and IL-1ß concentration in cerebral system. Meanwhile, brain and kidney were stained with hematoxylin and eosin (H&E) to observe pathological change. In 2nd week, both of T-SOD and Gu,Zn-SOD activity in serum increased obviously (P<0.05) in hyperuricemia rats. However, IL-1ß content didn't change remarkably. In the 4th week, T-SOD activity in model group had become similar with control group, and at the same time IL-1ß content in serum increased significantly (P<0.05). Pathological section showed the structural and functional unit of the kidney had been damaged. On the contrary, both of T-SOD and Gu,Zn-SOD activity in brain increased obviously (P<0.05), but IL-1ß concentration was no significant difference between two groups. In addition, the results of Evans Blue and H&E suggested the integrity of BBB and structure of brain were not changed after PO treatment. The permeability of BBB and form of UA would be potential factors to decide what kind role UA play on keeping balance between anti-oxidative stress and induction of inflammatory response.

Regeneração de nervos periféricos: terapia celular e fatores neurotróficos / Peripheral nerve regeneration: cell therapy and neurotrophic factors

Traumatismos em nervos periféricos resultam na perda de função do órgão inervado e raramente apresentam recuperação sem a intervenção cirúrgica. Diversas técnicas cirúrgicas são passíveis de serem empregadas para o reparo nervoso. Dentre elas, ressalta-se o uso da técnica de tubulização, podendo ser acrescentados fatores com capacidade regenerativa na câmara. A terapia celular e engenharia de tecidos surgem como uma alternativa para estimular e auxiliar a regeneração de nervos periféricos. Portanto, o objetivo desta revisão é fornecer um levantamento e uma análise de estudos experimentais e clínicos, quanto aos resultados obtidos, que utilizam a terapia celular e engenharia de tecidos como ferramentas para otimizar o processo de regeneração. Os artigos utilizados são oriundos de bases de dados científicas LILACS e Medline, através de pesquisas realizadas no PubMed e SciELO. Artigos sobre o uso de células-tronco, células de Schwann, fatores de crescimento, colágeno, laminina e plasma rico em plaquetas no reparo de nervos periféricos foram sintetizados ao longo da revisão. Com base nos diversos estudos pode-se concluir que a utilização de células-tronco derivadas de diferentes fontes apresentam resultados promissores na regeneração nervosa, pois estas possuem capacidade de diferenciação neuronal, demonstrando, assim, resultados funcionais eficazes. O uso de tubos acrescidos de elementos bioativos com liberação controlada também otimiza o reparo nervoso, promovendo uma maior mielinização e crescimento axonal dos nervos periféricos. Outro tratamento promissor é o uso de plasma rico em plaquetas, que, além de liberar fatores de crescimento importantes no reparo nervoso, ainda serve como um carreador para fatores exógenos estimulando a proliferação de células específicas no reparo de nervo periférico.

Peripheral nerve trauma results in functional loss in the innervated organ, and recovery without surgical intervention is rare. Many surgical techniques can be used for nerve repair. Among these, the tubulization technique can be highlighted: this allows regenerative factors to be introduced into the chamber. Cell therapy and tissue engineering have arisen as an alternative for stimulating and aiding peripheral nerve regeneration. Therefore, the aim of this review was to provide a survey and analysis on the results from experimental and clinical studies that used cell therapy and tissue engineering as tools for optimizing the regeneration process. The articles used came from the LILACS, Medline and SciELO scientific databases. Articles on the use of stem cells, Schwann cells, growth factors, collagen, laminin and platelet-rich plasma for peripheral nerve repair were summarized over the course of the review. Based on these studies, it could be concluded that the use of stem cells derived from different sources presents promising results relating to nerve regeneration, because these cells have a capacity for neuronal differentiation, thus demonstrating effective functional results. The use of tubes containing bioactive elements with controlled release also optimizes the nerve repair, thus promoting greater myelination and axonal growth of peripheral nerves. Another promising treatment is the use of platelet-rich plasma, which not only releases growth factors that are important in nerve repair, but also serves as a carrier for exogenous factors, thereby stimulating the proliferation of specific cells for peripheral nerve repair.

Schwannoma in Head and Neck: Preoperative Imaging Study and Intracapsular Enucleation for Functional Nerve Preservation

PURPOSE: In treating schwannoma patients, it is critical to determine the origin of the tumor to preserve nerve function. We evaluated the validity of preoperative imaging studies in distinguishing the neurological origin of the schwannomas of the head and neck, and the efficacy of intracapsular enucleation in preserving nerve function. MATERIALS AND METHODS: In 7 cases of schwannomas in the head and neck region, we predicted whether the tumor originated from the vagus nerve or the cervical sympathetic chain through imaging studies including computed tomography (CT) and magnetic resonance imaging (MRI). All patients were performed intracapsular enucleation, and the function of the vagus nerve and the sympathetic nerve was evaluated preoperatively and postoperatively. RESULTS: Preoperative imaging studies showed 6 cases where the tumor was located between the carotid artery and the internal jugular vein, and 1 case where the tumor was located posteriorly, displacing the carotid artery and the internal jugular vein anteriorly. At the time of operation, we confirmed schwannoma originating from the vagus nerve on the first 6 cases, and schwannoma originating from the sympathetic nervous system on the last case. All patients went through successful intracapsular enucleation, and of the seven schwannoma cases, 6 patients maintained normal postoperative neurological function (85.7%). CONCLUSION: Preoperative imaging studies offer valuable information regarding the location and origination of the tumor, and intracapsular enucleation helped us to preserve the nerve function.

Utilização das células-tronco no tratamento das lesões traumáticas de nervos: artigo de revisão / Therapeutic use of stem cells in traumatic peripheral nerve lesions: a review

Numerosas pesquisas avaliam a utilização de de células-tronco em uma grande variedade de lesões e patologias resultando na expansão do conhecimento atual da biologia dessas células. No sistema nervoso periférico, apesar de restrita às investigações experimentais, a utilização dessa terapêutica mostra resultados promissores em diversas linhas de pesquisa. Nas lesões traumáticas de nervos, essas células podem repor os neurônios motores e/ou sensitivos ou incrementar a população das células de Scwann, tornando a regeneração mais eficiente. A presente revisão analisa as possibilidades do uso das células-tronco aplicadas no reparo de nervos e sua regeneração.

Neuropraxia de miembro superior posterior a un bloqueo de plexo braquial / Neuropraxia of the superior limb after a blockade of the brachial plexus

La incidencia de las complicaciones neurológicas relacionadas causalmente o no con los bloqueos regionales es baja, pero como sus efectos pueden ser devastadores, con secuelas graves y permanentes, es importante conocer sus posibles causas con el fin de evitarlas. Las lesiones de los nervios periféricos pueden sucederse en el proceso perioperatorio, y constituyen un grupo conocido que es objeto de frecuentes reclamaciones, siendo el plexo braquial uno de los más frecuentemente afectados . Se presenta un caso de neuropraxia posterior al bloqueo del plexo braquial por abordaje interescalénico para una cirugía traumatológica de miembro superipr derecho, señalando la presencia de numerosos factores que podrían ser responsables de dicha lesión neurológica. Se realiza el análisis de las causas más probables del accidente con el fin de minimizar la incidencia de estas complicaciones, finalizando con la realización de las recomendaciones y consideraciones generales que nos permiten a realizar un bloqueo periférico en óptimas condiciones de seguridad.

The incidence of neurological complications after a regional blockade is low, but the effects could be devastating because of permanent and severe lesions. The knowledge of the possible causes of this complications is very important in order to avoid them. The peripherical nerve lesions could appear during the perioperative process and are frequently objects of claims, one of the most frequently affected is the brachial plexus. We presented a case of postoperative neuropraxia after a brachial plexus blockade by interescalenic access for an orthopedic surgery of the superior extremity, showing how many factors could be involved in this bad outcome. Trying to minimize the incidence of this complication, we analyze the probable causes of the accident, ending it with the general recommendations and considerations which allows us to make a successful peripherical blockade with the optimal safety conditions.

A incidência de complicações neurológicas relacionadas com os bloqueios regionais é baixa, porém, como os efeitos podem ser devastadores, com sequelas graves e permanentes, é importante conhecer suas possíveis causas com a finalidade de evita-las futuramente. As lesões dos nervos periféricos podem acontecer durante o periodo peri-operatório, e forman um grupo conhecido de frequentes reclamações , sendo o plexo braquial o mais atingido. Apresentamos um caso de neuropraxia logo após o bloqueio do plexo braquial por abordagem interescalênica para uma cirurgia traumatológica de membro superior direito, indicando a presença de numerosos fatores que podem ser responsáveis pêla lesão neurológica. Analizamos as causas mais prováveis do incidente com a finalidade de minimizar esta complicação. Finalmente faremos considerações e recomendações gerais que nos permitam realizar um bloqueio em ótimas condições de segurança.

Effect of hyperbaric oxygen on the regeneration of experimental crush injuries of nerves

O oxigenio hiperbarico exerce efeitos comprovadamente beneficos no tratamento de lesoes isquemicas agudas de partes moles e em feridas de dificil cicatrizacao. Nas lesoes neurais por esmagamento, os mecanismos fisiopatologicos assemelham-se aos efeitos dependentes da isquemia tissular. Portanto, a terapia com oxigenio hiperbarico teria participacao nos processos de reparacao neural, que constitui um dos pontos criticos para a recuperacao funcional apos as lesoes por esmagamento de nervos perifericos...

Upper extremity nerve lesions (diagnosis, indications, surgical techniques)

Objetive: Revision and questioning of orthodox principles regarding the conduction of nerve impulse. Design: Retrospective study with clinical analysis of results. Site: Hospital das Clinicas (HCFMSP), public university institution with research programs and tertiary attention to health. Group members: Author and a team of residents and trainees. Operation:Direct suture of nervous stumps utilizing auxiliary technical procedures:- joint-flexion, nerve transpositon, tendon transplants, bone shortening. Measurement: Clinical evaluation and objective tests for tactile and stereognostic function recovery (Weber Test). Results: Variable, depending on preoperative conditions: - type of lesion, time elapsed since injury. Conclusions: Neurorrhaphy should be the procedure of choice even for long term lesions, although the expected results may be less favourable. Periodical evaluation from 24 hs. Postoperative, checking for early undefined signals of nervous function recovery. Association of specific drugs for chemical biophysics of the nerve.