Restorative Neurology and Neuroscience - Volume 23, issue 2

Authors: Peurala, Sinikka H. | Titianova, Ekaterina B. | Mateev, Plamen | Pitkänen, Kauko | Sivenius, Juhani | Tarkka, Ina M.

Article Type: Research Article

Abstract: Purpose: To assess the effects of rehabilitation in thirty-seven ambulatory patients with chronic stroke during three weeks in-patient rehabilitation period. Methods: In the intervention group, each patient received 75 min physiotherapy daily every workday including 20 minutes in the electromechanical gait trainer with body-weight support (BWS). In the control group, each patient participated in 45 min conventional physiotherapy daily. Motor ability was assessed with the first five items of the Modified Motor …Assessment Scale (MMAS_{1-5} ) and ten meters walking speed. Spatio-temporal gait characteristics were recorded with an electrical walkway. Results: The MMAS_{1-5} (p < 0.0005 and p = 0.005) and ten meters walking time (p < 0.0005 and p = 0.006) improved in both groups. The improvements in MMAS_{1-5} and ten meters walking time did not differ between the groups (p = 0.217 and p = 0.195). Specific gait characteristics improved only in the intervention group, as seen in increased Functional Ambulation Profile score (p = 0.023), velocity (p = 0.023), the step lengths (affected side, p = 0.011, non-affected side p = 0.040), the stride lengths (p = 0.018, p = 0.006) and decreased step-time differential (p = 0.043). Furthermore, all gait characteristics and other motor abilities remained in the discharge level at the six months in the intervention group. Conclusions: It appears that BWS training gives a long-lasting benefit in gait qualities even in chronic stroke patients. Show more

Keywords: walking, cerebrovascular disorders, hemiparesis, neurorehabilitation, body-weight support

Citation: Restorative Neurology and Neuroscience, vol. 23, no. 2, pp. 57-65, 2005

Authors: Hoane, Michael R.

Article Type: Research Article

Abstract: Purpose: Previous studies have shown that administration of MgCl_{2} in animal models of brain injury significantly improves functional recovery: however, few studies have examined cognitive recovery. The present study evaluated the effect of MgCl_{2} pharmacotherapy on recovery of function following medial frontal cortex contusion injury. Methods: Groups of rats were assigned to either MgCl_{2} (1.0 mmol/kg) or saline treatment conditions and prepared with contusion …injuries or shams. Drug treatment was administered 15 min and 24 hr following injury. Rats were examined on tests of sensorimotor performance (bilateral tactile adhesive removal) and cognitive ability (reference and working memory). Results: Administration of MgCl_{2} following injury significantly reduced the behavioral impairments observed on the bilateral tactile removal test. The acquisition of reference memory was also significantly improved compared to saline-treated rats; however, treatment did not improve working memory performance. Lesion analysis revealed that administration of MgCl_{2} did not significantly reduce lesion size compared to saline-treatment. Examination of glial fibrillary acidic protein (GFAP) expression showed that MgCl_{2} did significantly reduce the number of GFAP^+ cells. Conclusion: These results indicate that MgCl_{2} administration significantly improved behavioral outcome following injury in a task dependent manner and reduced GFAP expression. Show more

Keywords: MgCl_{2}, recovery of function, rat, sensorimotor, cognition, neurotrauma, neuroprotection, gliosis

Citation: Restorative Neurology and Neuroscience, vol. 23, no. 2, pp. 67-77, 2005

Authors: Scherman, Peter | Kanje, Martin | Dahlin, Lars B.

Article Type: Research Article

Abstract: Purpose: We investigated whether sutures could guide regeneration across bifurcated nerve defects and how the number of sutures influenced regeneration. Methods: Bilateral ten mm defects in the rat sciatic nerve were bridged by either two or six laps of longitudinal (8/0 polyglactin) sutures. Bilateral ten mm defects including the bifurcation of tibial and peroneal nerves were bridged by two laps to the tibial and four laps to the peroneal nerve on one side and vice versa …on the other. Evaluation of tetanic force, weights of the gastrocnemius and caudal tibial muscles and morphometry of the nerves were performed at twelve weeks. Results: Simple defects bridged by six laps yielded a significantly greater number of myelinated axons compared to two laps. In the bifurcated defects a well defined two branched nerve structure was formed in all cases between the sciatic nerve and its peroneal and tibial branches. However, in the bifurcated model the tibial nerve attracted more axons than the peroneal irrespective of the number of suture laps. Conclusions: There is no simple correlation between the number of sutures and the number of regenerating axons but two suture laps may be insufficient for the repair of a rat sciatic nerve. Sutures supported reconstruction of new fascicles across bifurcated nerve defects. Show more

Keywords: suture, nerve regeneration, bifurcation, tetanic force, muscle weight

Citation: Restorative Neurology and Neuroscience, vol. 23, no. 2, pp. 79-85, 2005

Authors: Hartonian, Ivet | de Lacalle, Sonsoles

Article Type: Research Article

Abstract: Purpose: To investigate the plastic capacity of the cholinergic system in a partial animal model of Alzheimer's disease. Methods: Rats received unilateral lesions of the horizontal diagonal band of Broca (HDB) using a cholinergic-specific toxin, 192 IgG-saporin. After the appropriate survival time (2, 4, 8, 12 and 24 weeks post-lesion) rats were sacrificed and the brains were prepared for histology. Immunocytochemical and morphometric techniques were employed to quantify the cholinergic neurons surviving the lesion and …to measure the density of cortical cholinergic fibers. Results: Cell counts revealed on average a 60% reduction in cholinergic neurons on the lesioned side, compared to the spared side. This cell loss was permanent, that is, there was no significant change in the amount of cell loss over time. In correlation with this cell loss, cholinergic fibers in the target area, the entorhinal cortex (EC), were also reduced such that the density of acetylcholinesterase (AChE)-stained fibers on the lesioned side was 44% of the spared side. The density of cholinergic fibers in the EC increased significantly between 2 and 12 weeks post-lesion (p = 0.0216) but remained stable at that level by 24 weeks after the lesion. Conclusions: Following a cholinergic-specific lesion, a compensatory mechanism is activated in the basal forebrain cholinergic system, such that surviving neurons, projecting to the same target, extend their terminals to occupy the denervated area. It remains to be investigated whether these sprouts are able to establish proper synaptic connections and make a functional recovery in this particular system. Show more

Keywords: plasticity, basal forebrain, cholinergic system, outgrowth, acetylcholine, immunocytochemistry, rat

Citation: Restorative Neurology and Neuroscience, vol. 23, no. 2, pp. 87-96, 2005

Authors: Puigdellívol-Sánchez, Anna | Prats-Galino, Alberto | Molander, Carl

Article Type: Research Article

Abstract: Purpose: This study examines the proportions of regenerative and collateral sprouting to the skin after peripheral nerve injury. Methods: In the first experimental paradigm, primary afferent neurones were pre-labelled with Diamidino Yellow (DY), injected in digit 3, followed by sciatic nerve section and repair. After three months of regeneration, digit 3 was re-injected with Fast Blue (FB) to label regenerating cells. Fluoro-Gold (FG) was applied to the femoral (FEM) and musculocutaneous (MC) nerves four …days later to quantify their contribution to the innervation. In the second experimental paradigm, sciatic nerve was first sectioned and repaired. Three months later, the sciatic was resected, and digit 3 injected with FB. After four more days, FEM and MC were resected and FG injected in all digits. Results: Neurones in dorsal root ganglion (DRG) L5 had a higher rate of correct reinnervation of digit 3 (44–72%) than neurones in DRG L4 (14–44%). Like in control cases, only occasional axons were traced from the FEM and MC. In the second experiment, only occasional labelled neurones appeared. Conclusions: The results indicate differences in the capacity for correct peripheral sensory reinnervation between segmental levels, and that in this model collateral sprouting was practically non-existent compared to regenerative sprouting. Show more

Keywords: nerve regeneration, DRG, fluorescent dyes, adult rat

Citation: Restorative Neurology and Neuroscience, vol. 23, no. 2, pp. 97-107, 2005