Primary Blast Traumatic Brain Injury in the Rat: Relating Diffusion Tensor Imaging and Behavior

The incidence of traumatic brain injury (TBI) among military personnel is at its highest point in U.S. history. Experimental animal models of blast have provided a wealth of insight into blast injury. The mechanisms of neurotrauma caused by blast, however, are still under debate. Specifically, it is unclear whether the blast shockwave in the absence of head motion is sufficient to induce brain trauma. In this study, the consequences of blast injury were investigated in a rat model of primary blast TBI. Animals were exposed to blast shockwaves with peak reflected overpressures of either 100 or 450 kPa (39 and 110 kPa incident pressure, respectively) and subsequently underwent a battery of behavioral tests. Diffusion tensor imaging (DTI), a promising method to detect blast injury in humans, was performed on fixed brains to detect and visualize the spatial dependence of blast injury. Blast TBI caused significant deficits in memory function as evidenced by the Morris Water Maze, but limited emotional deficits as evidenced by the Open Field Test and Elevated Plus Maze. Fractional anisotropy, a metric derived from DTI, revealed significant brain abnormalities in blast-exposed animals. A significant relationship between memory deficits and brain microstructure was evident in the hippocampus, consistent with its role in memory function. The results provide fundamental insight into the neurological consequences of blast TBI, including the evolution of injury during the sub-acute phase and the spatially dependent pattern of injury. The relationship between memory dysfunction and microstructural brain abnormalities may provide insight into the persistent cognitive difficulties experienced by soldiers exposed to blast neurotrauma and may be important to guide therapeutic and rehabilitative efforts

The Effect of High Dose Total Body Irradiation on ACTH, Corticosterone, and Catecholamines in the Rat

Total body irradiation (TBI) or partial body irradiation is a distinct risk of accidental, wartime, or terrorist events. Total body irradiation is also used as conditioning therapy before hematopoietic stem cell transplantation. This therapy can result in injury to multiple tissues and might result in death as a result of multiorgan failure. The hypothalamic–pituitary–adrenal (HPA) axis could play a causative role in those injuries, in addition to being activated under conditions of stress. In a rat model of TBI, we have established that radiation nephropathy is a significant lethal complication, which is caused by hypertension and uremia. The current study assessed HPA axis function in rats undergoing TBI. Using a head-shielded model of TBI, we found an enhanced response to corticotropin-releasing hormone (CRH) in vitro in pituitaries from irradiated compared with nonirradiated rats at both 8 and 70 days after 10-Gy single fraction TBI. At 70, but not 8 days, plasma adrenocorticotrophic hormone (ACTH) and corticosterone levels were increased significantly in irradiated compared with nonirradiated rats. Plasma aldosterone was not affected by TBI at either time point, whereas plasma renin activity was decreased in irradiated rats at 8 days. Basal and stimulated adrenal steroid synthesis in vitro was not affected by TBI. In addition, plasma epinephrine was decreased at 70 days after TBI. The hypothalamic expression of CRH messenger RNA (mRNA) and hippocampal expression of glucocorticoid receptor mRNA were unchanged by irradiation. We conclude that the hypertension of radiation nephropathy is not aldosterone or catecholamine-dependent but that there is an abscopal activation of the HPA axis after 10 Gy TBI. This activation was attributable at least partially to enhanced pituitary ACTH production

Adapted digital music players for individuals with severe impairments

This is the peer reviewed version of the following article: Saunders, M. D., Questad, K. A., Cullinan, T. B., & Saunders, R. R. (2011). Adapted Digital Music Players for Individuals with Severe Impairments. Behavioral Interventions : Theory & Practice in Residential & Community-Based Clinical Programs, 26(2), 10.1002/bin.327. http://doi.org/10.1002/bin.327, which has been published in final form at doi.org/10.1002/bin.327. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-ArchivingPortable music production devices, such as radios, cassette players and MP3 players have characteristics that make them less than ideal for teaching the cause-and-effect relationships that would enable children and adults with severe impairments to control them independently and appropriately. Even when adapted for control with adaptive switches, the relationship between switch closure and on-off operation results in contingency characteristics that can inhibit learning. Some solutions to these problems are described, and for those individuals who can learn with complex contingencies, some promising products are reviewed

A NOVEL COATING METHOD USED TO ENABLE MULTILAYER STRUCTURES WITH MICROSCALE SELECTIVE LASER SINTERING

The microscale selective laser sintering process (µSLS) is an additive manufacturing technique that enables the creation of metal features with sub-5 µm in-plane resolution. In this process, a layer of metal nanoparticle ink is deposited onto a substrate and positioned beneath an optical subsystem with a nanopositioning stage. Using a digital micromirror device, a laser is spatially modulated to selectively heat up particles in desired regions to cause sintering. The substrate is then moved to a coating station where a new layer of nanoparticle ink is applied atop the sintered features. Initially, the slot-die coating process was adopted as the recoating method for this technique. However, due to challenges with depositing consistent ink thickness across the recoated part and limitations with the minimum layer thickness achievable, a new approach inspired by blade coating has been developed to achieve layer thicknesses of less than 1 µm.Mechanical Engineerin

Persistent colonization with Tannerella forsythensis and loss of attachment in adolescents

Colonization with Tannerella forsythensis may characterize the conversion of periodontally healthy sites into diseased sites. This three-year study describes the prevalence of T forsythensis and its relationship to clinical loss of attachment (LOA) in a group of adolescents considered at risk of developing early chronic periodontitis. Adolescents with (LOA+) and without (LOA-) loss of attachment were examined at baseline and 1.5 and 3 yrs subsequently. On each occasion, attachment loss was measured on selected teeth, and the presence of T. forsythensis in their subgingival plaque samples was determined by PCR. T. forsythensis prevalence in LOA+ subjects at baseline (64%) increased to 82% and 86% on subsequent examinations. In contrast, prevalence of T. forsythensis in LOA- subjects was always significantly lower (25%, 36%, and 32%, respectively). The odds of loss of attachment were 8.16 times greater in subjects infected with T. forsythensis at each examination. These results suggest that T. forsythensis is strongly associated with loss of attachment in this adolescent population

Perceptions of European ME/CFS Experts Concerning Knowledge and Understanding of ME/CFS among Primary Care Physicians in Europe: A Report from the European ME/CFS Research Network (EUROMENE)

BACKGROUND AND OBJECTIVES: We have conducted a survey of academic and clinical experts who are participants in the European ME/CFS Research Network (EUROMENE) to elicit perceptions of general practitioner (GP) knowledge and understanding of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and suggestions as to how this could be improved. MATERIALS AND METHODS: A questionnaire was sent to all national representatives and members of the EUROMENE Core Group and Management Committee. Survey responses were collated and then summarized based on the numbers and percentages of respondents selecting each response option, while weighted average responses were calculated for questions with numerical value response options. Free text responses were analysed using thematic analysis. RESULTS: Overall there were 23 responses to the survey from participants across 19 different European countries, with a 95% country-level response rate. Serious concerns were expressed about GPs’ knowledge and understanding of ME/CFS, and, it was felt, about 60% of patients with ME/CFS went undiagnosed as a result. The vast majority of GPs were perceived to lack confidence in either diagnosing or managing the condition. Disbelief, and misleading illness attributions, were perceived to be widespread, and the unavailability of specialist centres to which GPs could refer patients and seek advice and support was frequently commented upon. There was widespread support for more training on ME/CFS at both undergraduate and postgraduate levels. CONCLUSION: The results of this survey are consistent with the existing scientific literature. ME/CFS experts report that lack of knowledge and understanding of ME/CFS among GPs is a major cause of missed and delayed diagnoses, which renders problematic attempts to determine the incidence and prevalence of the disease, and to measure its economic impact. It also contributes to the burden of disease through mismanagement in its early stages

A Literature Review of GP Knowledge and Understanding of ME/CFS: A Report from the Socioeconomic Working Group of the European Network on ME/CFS (EUROMENE)

Background and Objectives: The socioeconomic working group of the European myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) Research Network (EUROMENE) has conducted a review of the literature pertaining to GPs’ knowledge and understanding of ME/CFS; Materials and Methods: A MEDLINE search was carried out. The papers identified were reviewed following the synthesis without meta-analysis (SWiM) methodology, and were classified according to the focus of the enquiry (patients, GPs, database and medical record studies, evaluation of a training programme, and overview papers), and whether they were quantitative or qualitative in nature; Results: Thirty-three papers were identified in the MEDLINE search. The quantitative surveys of GPs demonstrated that a third to a half of all GPs did not accept ME/CFS as a genuine clinical entity and, even when they did, they lacked confidence in diagnosing or managing it. It should be noted, though, that these papers were mostly from the United Kingdom. Patient surveys indicated that a similar proportion of patients was dissatisfied with the primary medical care they had received. These findings were consistent with the findings of the qualitative studies that were examined, and have changed little over several decades; Conclusions: Disbelief and lack of knowledge and understanding of ME/CFS among GPs is widespread, and the resultant diagnostic delays constitute a risk factor for severe and prolonged disease. Failure to diagnose ME/CFS renders problematic attempts to determine its prevalence, and hence its economic impact