Wallerian degeneration: gaining perspective on inflammatory events after peripheral nerve injury

In this review, we first provide a brief historical perspective, discussing how peripheral nerve injury (PNI) may have caused World War I. We then consider the initiation, progression, and resolution of the cellular inflammatory response after PNI, before comparing the PNI inflammatory response with that induced by spinal cord injury (SCI)

Small-Group Learning in an Upper-Level University Biology Class Enhances Academic Performance and Student Attitudes Toward Group Work

To improve science learning, science educators' teaching tools need to address two major criteria: teaching practice should mirror our current understanding of the learning process; and science teaching should reflect scientific practice. We designed a small-group learning (SGL) model for a fourth year university neurobiology course using these criteria and studied student achievement and attitude in five course sections encompassing the transition from individual work-based to SGL course design. All students completed daily quizzes/assignments involving analysis of scientific data and the development of scientific models. Students in individual work-based (Individualistic) sections usually worked independently on these assignments, whereas SGL students completed assignments in permanent groups of six. SGL students had significantly higher final exam grades than Individualistic students. The transition to the SGL model was marked by a notable increase in 10th percentile exam grade (Individualistic: 47.5%; Initial SGL: 60%; Refined SGL: 65%), suggesting SGL enhanced achievement among the least prepared students. We also studied student achievement on paired quizzes: quizzes were first completed individually and submitted, and then completed as a group and submitted. The group quiz grade was higher than the individual quiz grade of the highest achiever in each group over the term. All students – even term high achievers –could benefit from the SGL environment. Additionally, entrance and exit surveys demonstrated student attitudes toward SGL were more positive at the end of the Refined SGL course. We assert that SGL is uniquely-positioned to promote effective learning in the science classroom

Preserved Adrenal Function After Lumbar Spinal Cord Transection Augments Low Pressure Bladder Activity in the Rat

Spinal cord injury (SCI) disconnects supraspinal micturition centers from the lower urinary tract resulting in immediate and long-term changes in bladder structure and function. While cervical and high thoracic SCI have a greater range of systemic effects, clinical data suggest that those with lower (suprasacral) injuries develop poorer bladder outcomes. Here we assess the impact of SCI level on acute changes in bladder activity. We used two SCI models, T3 and L2 complete transections in male Wistar rats, and compared bladder pressure fluctuations to those of naïve and bladder-denervated animals. By 2 days after L2 transection, but not T3 transection or bladder denervation, small amplitude rhythmic contractions (1 mmHg, 0.06 Hz) were present at low intravesical pressures (<6 mmHg); these were still present 1 month following injury, and at 3 months, bladders from L2 SCI animals were significantly larger than those from T3 SCI or naïve animals. Low-pressure contractions were unaffected by blocking ganglionic signaling or bladder denervation at the time of measurements. L2 (and sham surgery) but not T3 transection preserves supraspinal adrenal control, and by ELISA we show lower plasma adrenal catecholamine concentration in the latter. When an adrenalectomy preceded the L2 transection, the aberrant low-pressure contractions more closely resembled those after T3 transection, indicating that the increased bladder activity after lumbar SCI is mediated by preserved adrenal function. Since ongoing low-pressure contractions may condition the detrusor and exacerbate detrusor-sphincter dyssynergia, moderating bladder catecholamine signaling may be a clinically viable intervention strategy

The effectiveness of small-group-learning (SGL) is borne out in final exam performance.

<p>Grades from final exams were examined for five terms of a fourth-year Developmental Neurobiology course. Terms with similar learning environments were combined: students either worked in an Individualistic environment (2005 and 2006) or worked in permanent small groups (Initial SGL, 2007; and Refined SGL, 2008 and 2009). We incorporated changes in Refined SGL that improved on the design of the Initial SGL setting (e.g. by introducing individual quizzes prior to group quizzes). a) The class average for the final exam was higher in the Refined SGL environment than it was for both other groups. b) Box plots of the same data reveal an increase in median (line), 75^th percentile (upper limit of box) and 25^th percentile (lower limit of box) with the introduction of SGL. Whiskers represent the 10^th and 90^th percentiles: the grade at the 10^th percentile exhibits a remarkable, positive shift with the introduction of SGL. c,d). Comparison of exam grade distributions between these three groups showed that students in the Initial SGL performed better than students in the Individualistic setting, and that students in the Refined SGL environment performed better than students in both other groups. This indicates that our SGL environment benefits academic performance, and that refinements made since its initial implementation have made the SGL model more effective. Asterisks indicate significant differences between groups (Kruskal-Wallis ANOVA, Dunn's test (a); Kolmogorov-Smirnov goodness-of-fit test (d)); n = 61 (Individualistic), n = 76 (Initial SGL), n = 82 (Refined SGL).</p