Viability of nerve grafts preseved in different storage medium

We compared the structural features of nerve segments stored in two different solutions previous and after autologous transplantation. Male Wistar rats were divided into groups to obtain normal tibial nerves, freshly transplanted nerves, and nerves stored in Wisconsin/Belzer or Collins solution for 24 or 72 h at 4ºC and transplanted. Stored and transplanted segments were processed for morphologic and morphometric analysis. The cross-sections of segments stored in Wisconsin/Belzer and Collins solution presented aspects similar to that of normal nerves. The density of large-caliber myelinated axons was higher in grafts stored in Wisconsin/Belzer solution than in those preserved in Collins solution. But the density of myelinated axons regenerated through these grafts was around 80% to that registered in the fresh and Wisconsin/Belzer preserved grafts. Moreover, no significant differences in the morphometric parameters were observed between groups. Our data confirm the efficacy of Wisconsin/Belzer to nerve graft preservation and stimulate more detailed physiological, biochemical and molecular studies to rationalize the employment of less expensive and handful storage solutions for short term preservation of peripheral nerve grafts.

Naturally supraorganized collagen increases axonal regeneration after tubulization repair

After axotomy, regeneration can be enhanced by bridging the transected nerve with a biocompatible tube, and the effect of trophic substances or molecules from the extracellular matrix can be investigated by filling the prosthesis. In this study, we assessed the importance of the molecular organization and aggregational state of collagen type I in axonal regeneration and guidance. Two types of collagen were used, namely, a collagen gel derived from bovine tendon that displays supraorganization after extrusion, and collagen from rat tail which does not self-organize under such conditions. Adult male Wistar rats were divided into four groups. In the first group (n=3), the polyethylene tube was filled with bovine collagen, while in the second (n=3), the prosthesis was filled with rat-derived collagen. In the third group (n=3), the tube was left empty, and the fourth group (n=3), consisted of unoperated rats. Six weeks after tubulization, the number of axons was significantly higher with bovine collagen than with rat collagen (7,661 ± 1,018 versus 4,110 ± 1,027, p<0.05), as was the degree of implant absorption. These results support the hypothesis that the use of extracellular matrix substances that self-assembly in an organized pattern can enhance nerve regeneration.

The Martin-Gruber anastomosis in Brazilians: an anatomical study

Comunications between nerves are relatively common, and individual variations in their anatomical organization have been described. Knowledge of the prevalence of such variations is necessary when establishing the diagnosis of both sexes, were dissected to examine the communication between the median and ulnar nerves (Martin-Gruber anastomosis). This anastomosis was found in five cases (7.8 por cento) one of which was bilateral. There were no significant gender or racial differences in the incidence of this connection. The anastomosis showed secondary branches in two cases, and ran posteriorly to the ulnar artery in three cases, and advanced anteriorly to the flexor digitorum profundus muscles in all cases. Despite the low incidence of Martin-Gruber anastomosis in Brazilians observed here, the importance of an adequate investigation of these connections needs to be underscored. Understanding the existence of this variation, its location and its possible presentation is important for correct patient assistance.

The Martin-Gruber anastomosis in brazilians: an anatomical study

Communications between nerves are relatively common, and individual variations in their anatomical organization have been described. Knowledge of the prevalence of such variations is necessary when estabilishing the diagnosis of neuropathies and surgical landmarks. In this study, 64 anterior forearm regions of cadavers of blacks and whites of both sexes, were dissected to examine the communications between the median and ulnar nerves (Martin-Gruber anastomosis). This anastomosis was found in five cases (7,8%), one of which was bilateral. There were no significant gender or racial differences in the incidence of this connection. The anastomosis in Brazilians observed here, the impoprtance of an adequate investigation of these connections needs to be underscored. Understanding the existence of this variations, its location and its possible presentation is important for correct patient assistance.

Estudo morfológico de ducto deferente em ratos submetidos à vasectomia convencional e a laser de argônio / Morphological study of the vas deferens in rats submitted to conventional and argonium laser vasectomy

Dois grupos de 5 ratos foram submetidos a vasectomia convencional (A) e a raio laser de Argônia (B). No trigésimo dia de pós-operatório os animais foram sacrificados e os ductos deferentes observados sob visäo direta e ao microscópio óptico. Macroscopicamente observou-se em todos os casos a formaçäo de uma tumoraçäo no ápice do coto proximal do ducto deferente. O restante do aparelho permaneceu íntegro. Microscopicamente em ambos os grupos notou-se uma dilataçäo da luz do ducto, o epitélio tornou-se plano com perda de estereocílios e esgarçamento da camada muscular. Além disso, observou-se uma formaçäo tumoral com conteúdo espermático e colóide, circundada por macrófagos e células gigantes, envoltos por uma camada fibrosa. Esta formaçäo constitui-se no granuloma espermático. Näo foram observados significativas entre os métodos aplicados