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Abstract Background Harsh environments surrounding fetuses and children can induce cellular damage in the developing brain, increasing the risk of intellectual disability and other neurodevelopmental disorders such as schizophrenia. However, the mechanisms by which early damage leads to disease manifestation in later life remain largely unknown. Previously, we demonstrated that the activation of heat shock (HS) signaling can be utilized as a unique reporter to label the cells that undergo specific molecular/cellular changes upon exposure to environmental insults throughout the body. Since the activation of HS signaling is an acute and transient event, this approach was not intended for long-term tracing of affected cells after the activation has diminished. In the present study, we generated new reporter transgenic mouse lines as a novel tool to achieve systemic and long-term tracking of affected cells and their progeny. Methods The reporter transgenic mouse system was designed so that the activation of HS signaling through HS response element (HSE) drives flippase (FLPo)-flippase recognition target (FRT) recombination-mediated permanent expression of the red fluorescent protein (RFP), tdTomato. With a priority on consistent and efficient assessment of the reporter system, we focused on intraperitoneal (i.p.) injection models of high-dose, short prenatal exposure to alcohol (ethanol) and sodium arsenite (ethanol at 4.0 g/kg/day and sodium arsenite at 5.0 mg/kg/day, at embryonic day (E) 12 and 13). Long-term reporter expression was examined in the brain of reporter mice that were prenatally exposed to these insults. Electrophysiological properties were compared between RFP+ and RFP− cortical neurons in animals prenatally exposed to arsenite. Results We detected RFP+ neurons and glia in the brains of postnatal mice that had been prenatally exposed to alcohol or sodium arsenite. In animals prenatally exposed to sodium arsenite, we also detected reduced excitability in RFP+ cortical neurons. Conclusion The reporter transgenic mice allowed us to trace the cells that once responded to prenatal environmental stress and the progeny derived from these cells long after the exposure in postnatal animals. Tracing of these cells indicates that the impact of prenatal exposure on neural progenitor cells can lead to functional abnormalities in their progeny cells in the postnatal brain. Further studies using more clinically relevant exposure models are warranted to explore this mechanism.

Many governments have promoted the development of a civil society to encourage citizen involvement in addressing many of the grand social challenges such as the growing prevalence of dementia, as ageing becomes a major trend in developed societies. One outcome has been the development of Dementia Friendly Communities, created via Dementia Action Alliances (DAAs) in England, to enhance awareness, care and the experience of people with dementia in accessing services and facilities. These initiatives are based on engaging the business community and yet no research studies have examined this theme to date. Given the growing significance of leisure and tourism activities that people with dementia and family members engage in, this study examines the experience of business engagement with DAAs in the visitor economy in England. The notion of shared value articulated by Porter and Kramer (2011) is used as a basis for understanding the type of business engagement.

Objectives. (a) To determine associations among motor evoked potential (MEP) amplitude, MEP latency, lower extremity (LE) impairment, and gait velocity and (b) determine the association between the presence of a detectable MEP signal with LE impairment and with gait velocity. Method. 35 subjects with chronic, stable LE hemiparesis were undergone TMS, the LE section of the Fugl-Meyer Impairment Scale (LE FM), and 10-meter walk test. We recorded presence, amplitude, and latency of MEPs in the affected tibialis anterior (TA) and soleus (SO). Results. MEP presence was associated with higher LEFM scores in both the TA and SO. MEP latency was larger in subjects with lower LEFM and difficulty walking. Conclusion. MEP latency appears to be an indicator of LE impairment and gait. Significance. Our results support the precept of using TMS, particularly MEP latency, as an adjunctive LE outcome measurement and prognostic technique.

Stroke remains a leading cause of disability worldwide, with a majority of survivors experiencing long term decrements in motor function that severely undermine quality of life. While many treatment approaches and adjunctive strategies exist to remediate motor impairment, many are only efficacious or feasible for survivors with active hand and wrist function, a population who constitute only a minority of stroke survivors. Transcranial direct current stimulation (tDCS), a type of noninvasive brain stimulation, has been increasingly utilized to increase motor function following stroke as it is able to be used with stroke survivors of varying impairment levels, is portable, is relatively inexpensive and has few side effects and contraindications. Accordingly, in recent years the number of studies investigating its efficacy when utilized as an adjunct to motor rehabilitation regimens has drastically increased. While many of these trials have reported positive and promising efficacy, methodologies vary greatly between studies, including differences in stimulation parameters, outcome measures and the nature of physical practice. As such, an urgent need remains, centering on the need to investigate these methodological differences and synthesize the most current evidence surrounding the application of tDCS for post-stroke motor rehabilitation. Accordingly, the purpose of this paper is to provide a detailed overview of the most recent tDCS literature (published 2014-2015), while highlighting these variations in methodological approach, as well to elucidate the mechanisms associated with tDCS and post-stroke motor re-learning and neuroplasticity.

Objective. To determine the National Institutes of Health Stroke Scale’s (NIHSS’s) association with upper extremity (UE) impairment and functional outcomes. Design. Secondary, retrospective analysis of randomized controlled trial data. Setting. Not applicable. Participants. 146 subjects with stable, chronic stroke-induced hemiparesis. Intervention. The NIHSS, the UE Fugl-Meyer (FM), and the Arm Motor Ability Test (AMAT) were administered prior to their participation in a multicenter randomized controlled trial. Main Outcome Measures. The NIHSS, FM, and AMAT. Results. The association between the NIHSS and UE impairment was statistically significant (P=-0.204;p=0.014) but explained less than 4% of the variance among UE FM scores. The association between NIHSS total score and function as measured by the AMAT was not statistically significant (P=-0.141;p=0.089). Subjects scoring a “zero” on the NIHSS exhibited discernible UE motor deficits and varied scores on the UE FM and AMAT. Conclusion. While being used in stroke trials, the NIHSS may have limited ability to discriminate between treatment responses, even when only a relatively narrow array of impairment levels exists among patients. Given these findings, NIHSS use should be restricted to acute stroke studies and clinical settings with the goal of reporting stroke severity.