Mild traumatic brain injury (mTBI) is considered the ‘signature injury’ of combat veterans that have served during the wars in Iraq and Afghanistan. This prevalence of mTBI is due in part to the common exposure to high explosive blasts in combat zones. In addition to the threats of blunt impact trauma caused by flying objects and the head itself being propelled against objects, the primary blast overpressure (BOP) generated by high explosives is capable of injuring the brain. Compared to other means of causing TBI, the pathophysiology of mild-to-moderate BOP is less well understood. To study the consequences of BOP exposure in mice, we employed a well-established approach using a compressed gas-driven shock tube that recapitulates battlefield-relevant open-field BOP. We found that 24 hours post-blast a single mild BOP provoked elevation of multiple phosphor- and cleaved-tau species in neurons, as well as elevating manganese superoxide-dismutase (MnSOD or SOD2) levels, a cellular response to oxidative stress. In hippocampus, aberrant tau species persisted for at least 30 days post-exposure, while SOD2 levels returned to sham control levels. These findings suggest that elevated phospho- and cleaved-tau species may be among the initiating pathologic processes induced by mild blast exposure. These findings may have important implications for efforts to prevent blast-induced insults to the brain from progressing into long-term neurodegenerative disease processes.

As an inflammatory airway disease, asthma is expected to be associated with an increase in airway blood flow. We therefore compared airway mucosal blood flow (Qaw) among normal subjects (n = 11) and patients with stable asthma receiving (n = 13) or not receiving (n = 10) long-term inhaled glucocorticosteroid (GS) therapy. Qaw was calculated from the uptake of dimethyl ether in the anatomic dead space minus the most proximal 50 ml (DS), and expressed as blood flow per ml DS. Mean (+/- SE) Qaw was 38.5 +/- 5. 3 microl . min-1 . ml-1 in normals, 68.2 +/- 7.9 microl . min-1 . ml-1 in GS-naive asthmatics (p < 0.01), and 55.4 +/- 5.3 microl . min-1 . ml-1 in GS-treated asthmatics (p < 0.05). Ten minutes after administration of 180 microg albuterol by metered dose inhaler, mean Qaw increased by 83 +/- 26% in normal subjects (p < 0.01), but did not change significantly in GS-naive (+5 +/- 8%) or GS-treated (+32 +/- 15%) asthmatics. These results demonstrate that Qaw is increased in stable asthmatics and resistant to further increase by a standard inhaled dose of a beta-adrenergic agonist.

I conducted a survey of 102 senior physical therapy students to identify, from the students' perspective, training needs for clinical instructors. The literature identified 43 clinical instructor behaviors in four categories (communication, interpersonal relations, professional skills, and teaching behaviors). Students scored these behaviors, for their importance and frequency. Results demonstrated all behaviors were perceived as somewhat significant and frequent. The students scored communication as most important followed by interpersonal relations, teaching, and professional skills behaviors. Frequency of the 43 behaviors was evenly distributed among the four categories. Correlational analysis of the perceived importance with the frequency of each behavior yielded 9 statistically significant positive correlations, no negative correlations, and 16 near random correlations. Positive correlations were 56 percent professional skills and 44 percent teaching behaviors. Near random correlations were 38 percent communication, 6 percent interpersonal relations, 6 percent professional skills behaviors, and 50 percent teaching. These 16 behaviors are identified as the target for clinical instructor training programs. This method in individual clinical settings is discussed briefly.