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Introduction The association between hypothermia, coagulopathy, and acidosis in trauma is well described. Hypothermia mitigation starts in the prehospital setting; however, it is often a secondary focus after other life-saving interventions. The deployed environment further compounds the problem due to prolonged evacuation times in rotary wing aircraft, resource limitations, and competing priorities. This analysis evaluates hypothermia in combat casualties and the relationship to resuscitation strategy with blood products. Methods Using the data from the Department of Defense Joint Trauma Registry from 2003 to 2021, a retrospective analysis was conducted on adult trauma patients. Inclusion criteria was arrival at the first military treatment facility (MTF) hypothermic (<95ºF). Study variables included: mortality, year, demographics, battle vs non-battle injury, mechanism, theater of operation, vitals, and labs. Subgroup analysis was performed on severely injured (15 < ISS < 75) hypothermic trauma patients resuscitated with whole blood (WB) vs only component therapy. Results Of the 69,364 patients included, 908 (1.3%) arrived hypothermic; the vast majority of whom (N  = 847, 93.3%) arrived mildly hypothermic (90–94.9°F). Overall mortality rate was 14.8%. Rates of hypothermia varied by year from 0.7% in 2003 to 3.9% in 2014 (P <0.005). On subgroup analysis, mortality rates were similar between patients resuscitated with WB vs only component therapy; though base deficit values were higher in the WB cohort (−10 vs −6, P  < 0.001). Conclusion Despite nearly 20 years of combat operations, hypothermia continues to be a challenge in military trauma and is associated with a high mortality rate. Mortality was similar between hypothermic trauma patients resuscitated with WB vs component therapy, despite greater physiologic derangements on arrival in patients who received WB. As the military has the potential to conduct missions in environments where the risk of hypothermia is high, further research into hypothermia mitigation techniques and resuscitation strategies in the deployed setting is warranted. [ABSTRACT FROM AUTHOR]

Myriapods (e.g., centipedes and millipedes) display a simple homonomous body plan relative to other arthropods. All members of the class are terrestrial, but they attained terrestriality independently of insects. Myriapoda is the only arthropod class not represented by a sequenced genome. We present an analysis of the genome of the centipede Strigamia maritima. It retains a compact genome that has undergone less gene loss and shuffling than previously sequenced arthropods, and many orthologues of genes conserved from the bilaterian ancestor that have been lost in insects. Our analysis locates many genes in conserved macro-synteny contexts, and many small-scale examples of gene clustering. We describe several examples where S. maritima shows different solutions from insects to similar problems. The insect olfactory receptor gene family is absent from S. maritima, and olfaction in air is likely effected by expansion of other receptor gene families. For some genes S. maritima has evolved paralogues to generate coding sequence diversity, where insects use alternate splicing. This is most striking for the Dscam gene, which in Drosophila generates more than 100,000 alternate splice forms, but in S. maritima is encoded by over 100 paralogues. We see an intriguing linkage between the absence of any known photosensory proteins in a blind organism and the additional absence of canonical circadian clock genes. The phylogenetic position of myriapods allows us to identify where in arthropod phylogeny several particular molecular mechanisms and traits emerged. For example, we conclude that juvenile hormone signalling evolved with the emergence of the exoskeleton in the arthropods and that RR-1 containing cuticle proteins evolved in the lineage leading to Mandibulata. We also identify when various gene expansions and losses occurred. The genome of S. maritima offers us a unique glimpse into the ancestral arthropod genome, while also displaying many adaptations to its specific life history.

With integrated curricula and multidisciplinary assessments becoming more prevalent in medical education, there is a continued need for educational research to explore the advantages, consequences, and challenges of integration practices. This retrospective analysis investigated the number of items needed to reliably assess anatomical knowledge in the context of gross anatomy and histology. A generalizability analysis was conducted on gross anatomy and histology written and practical examination items that were administered in a discipline-based format at Indiana University School of Medicine and in an integrated fashion at the University of Alabama School of Medicine and Rush University Medical College. Examination items were analyzed using a partially nested design [sx(i:o)] in which items were nested within occasions (i:o) and crossed with students (s). A reliability standard of 0.80 was used to determine the minimum number of items needed across examinations (occasions) to make reliable and informed decisions about students' competence in anatomical knowledge. Decision study plots are presented to demonstrate how the number of items per examination influences the reliability of each administered assessment. Using the example of a curriculum that assesses gross anatomy knowledge over five summative written and practical examinations, the results of the decision study estimated that 30 and 25 items would be needed on each written and practical examination to reach a reliability of 0.80, respectively. This study is particularly relevant to educators who may question whether the amount of anatomy content assessed in multidisciplinary evaluations is sufficient for making judgments about the anatomical aptitude of students.

Postnatal decreases in vascular reactivity involve decreases in the thick filament component of myofilament calcium sensitivity, which is measured as the relationship between cytosolic calcium concentration and myosin light chain ([MLC.sub.20]) phosphorylation. The present study tests the hypothesis that downregulation of thick filament reactivity is due to downregulation of myosin light chain kinase (MLCK) activity in adult compared with fetal arteries. Total MLCK activity, calculated as %[MLC.sub.20] phosphorylated per second in intact arteries during optimal inhibition of myosin light chain phosphatase activity, was significantly less in adult (6.56 [+ or -] 0.29%) than in fetal preparations (7.39 [+ or -] 0.53%). In situ [MLC.sub.20] concentrations ([micro]M) in adult (198 [+ or -] 28) and fetal arteries (236 [+ or -] 44) did not differ significantly. In situ MLCK concentrations ([micro]M), however, were significantly greater in adult (8.21 [+ or -] 0.59) than in fetal arteries (1.83 [+ or -] 0.13). In situ MLCK activities (ng [MLC.sub.20] phosphorylated * [s.sup.-1] * ng [MLCK.sup.-1]) were significantly less in adult (0.26 [+ or -] 0.01) than in fetal arteries (1.52 [+ or -] 0.11). In contrast, MLCK activities in adult (15.8 [+ or -] 1.5) and fetal artery homogenates (17.3 [+ or -] 1.3) were not significantly different. When in situ fractional activation was calculated, adult values (1.72 [+ or -] 0.17%) were significantly less than fetal values (9.08 [+ or -] 0.83%). Together, these results indicate that decreased thick filament reactivity in adult compared with fetal ovine carotid arteries is due at least in part to greater MLCK activity in fetal arteries, which in turn cannot be explained by differences in MLCK, [MLC.sub.20], or calmodulin concentrations. Instead, this difference appears to involve age-related differences in fractional activation of the MLCK enzyme. myofilament calcium sensitivity; postnatal maturation; regulatory myosin light chain; thick filament reactivity