Pain and Psychiatric Comorbidities Among Two Groups of Iraq- and Afghanistan-era Veterans

This study aimed to (1) identify the prevalence and severity of pain and psychiatric comorbidities among personnel who had been deployed during Operation Iraqi Freedom (OIF), Operation Enduring Freedom (OEF), and Operation New Dawn (OND) and (2) assess whether the Department of Veterans Affairs (VA) Polytrauma System of Care and an OIF/OEF/OND registry reflect real differences among patients. Participants (N = 359) were recruited from two VA hospitals. They completed a clinical interview, structured diagnostic interview, and self-report measures. Results indicated pain was the most common complaint, with 87% experiencing pain during the prior week and 56% reporting moderate or severe pain. Eighty percent of participants met criteria for at least one of seven assessed comorbid problems (moderate or severe pain, postconcussional disorder, posttraumatic stress disorder [PTSD], anxiety disorder, mood disorder, substance use disorder, psychosis), and 59 percent met criteria for two or more problems. PTSD and postconcussional disorder rarely occurred in the absence of pain or other comorbidities (0.3% and 0%, respectively). The Polytrauma group had more comorbid psychiatric conditions ( χ2 = 48.67, p\u3c 0.05) and reported greater severity of symptoms (p \u3c 0.05) than the Registry group. This study confirmed the high prevalence of pain and concurrent mental health problems among personnel returning from military deployment. Key words: Afghanistan, anxiety, blast injuries, chronic pain, combat disorders, comorbidities, depression, Iraq, postconcussive disorder, PTSD, sleep, substance use disorder, TBI, Veterans

Simulated winter warming negatively impacts survival of Antarctica's only endemic insect

1. Antarctic winters are challenging for terrestrial invertebrates, and species that live there have specialised adaptations to conserve energy and protect against cold injury in the winter. However, rapidly occurring climate change in these regions will increase the unpredictability of winter conditions, and there is currently a dearth of knowledge on how the highly adapted invertebrates of Antarctica will respond to changes in winter temperatures. 2. We evaluated the response of larvae of the Antarctic midge, Belgica antarctica, to simulated winters at three ecologically relevant mean temperature scenarios: warm (−1°C), normal (−3°C) and cold (−5°C). Within each scenario, larvae were placed into three distinct habitat types in which they are commonly observed (decaying organic matter, living moss, and Prasiola crispa algae). Following the simulated overwintering period, a range of physiological outcomes were measured, namely survival, locomotor activity, tissue damage, energy store levels and molecular stress responses. 3. Survival, energy stores and locomotor activity were significantly lower following the Warm overwintering environment than at lower temperatures, but tissue damage and heat shock protein expression (a proxy for protein damage) did not significantly differ between the three temperatures. Survival was also significantly lower in larvae overwintered in Prasiola crispa algae, although the underlying mechanism is unclear. Heat shock proteins were expressed least in larvae overwintering in living moss, suggesting it is less stressful to overwinter in this substrate, perhaps due to a more defined structure affording less direct contact with ice. 4. Our results demonstrate that a realistic 2°C increase in winter microhabitat temperature reduces survival and causes energy deficits that have implications for subsequent development and reproduction. While our Warm winter scenario was close to the range of observed overwintering temperatures for this species, warmer winters are expected to become more common in response to climate change. Conversely, if climate change reduces the length of winter, some of the negative consequences of winter warming may be attenuated, so it will be important to consider this factor in future studies. Nonetheless, our results indicate that winter warming could negatively impact cold-adapted insects such as the Antarctic midge

Continuous up-regulation of heat shock proteins in larvae, but not adults, of a polar insect

Antarctica's terrestrial environment is a challenge to which very few animals have adapted. The largest, free-living animal to inhabit the continent year-round is a flightless midge, Belgica antarctica. Larval midges survive the lengthy austral winter encased in ice, and when the ice melts in summer, the larvae complete their 2-yr life cycle, and the wingless adults form mating aggregations while subjected to surprisingly high substrate temperatures. Here we report a dichotomy in survival strategies exploited by this insect at different stages of its life cycle. Larvae constitutively up-regulate their heat shock proteins (small hsp, hsp70, and hsp90) and maintain a high inherent tolerance to temperature stress. High or low temperature exposure does not further up-regulate these genes nor does it further enhance thermotolerance. Such “preemptive” synthesis of hsps is sufficient to prevent irreversible protein aggregation in response to a variety of common environmental stresses. Conversely, adults exhibit no constitutive up-regulation of their hsps and have a lower intrinsic tolerance to high temperatures, but their hsps can be thermally activated, resulting in enhanced thermotolerance. Thus, the midge larvae, but not the adults, have adopted the unusual strategy of expressing hsps continuously, possibly to facilitate proper protein folding in a cold habitat that is more thermally stable than that of the adults but a habitat subjected frequently to freeze-thaw episodes and bouts of pH, anoxic, and osmotic stress