Faster refill in an urban emergency medical services system saves lives: A prospective preliminary evaluation of a prehospital advanced resuscitative care bundle.

INTRODUCTION: Military experience has demonstrated mortality improvement when advanced resuscitative care (ARC) is provided for trauma patients with severe hemorrhage. The benefits of ARC for trauma in civilian emergency medical services (EMS) systems with short transport intervals are still unknown. We hypothesized that ARC implementation in an urban EMS system would reduce in-hospital mortality. METHODS: This was a prospective analysis of ARC bundle administration between 2021 and 2023 in an urban EMS system with 70,000 annual responses. The ARC bundle consisted of calcium, tranexamic acid, and packed red blood cells via a rapid infuser. Advanced resuscitative care patients were compared with trauma registry controls from 2016 to 2019. Included were patients with a penetrating injury and systolic blood pressure ≤90 mm Hg. Excluded were isolated head trauma or prehospital cardiac arrest. In-hospital mortality was the primary outcome of interest. RESULTS: A total of 210 patients (ARC, 61; controls, 149) met the criteria. The median age was 32 years, with no difference in demographics, initial systolic blood pressure or heart rate recorded by EMS, or New Injury Severity Score between groups. At hospital arrival, ARC patients had lower median heart rate and shock index than controls ( p ≤ 0.03). Fewer patients in the ARC group required prehospital advanced airway placement ( p < 0.001). Twenty-four-hour and total in-hospital mortality were lower in the ARC group ( p ≤ 0.04). Multivariable regression revealed an independent reduction in in-hospital mortality with ARC (odds ratio, 0.19; 95% confidence interval, 0.05-0.68; p = 0.01). CONCLUSION: Early ARC in a fast-paced urban EMS system is achievable and may improve physiologic derangements while decreasing patient mortality. Advanced resuscitative care closer to the point of injury warrants consideration. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level IV.

Single-Cell Transcriptome Analysis of the Circle of Willis in a Mouse Cerebral Aneurysm Model.

BACKGROUND: The circle of Willis (CoW) is the most common location for aneurysms to form in humans. Although the major cell types of the intracranial vasculature are well known, the heterogeneity and relative contributions of the different cells in healthy and aneurysmal vessels have not been well characterized. Here, we present the first comprehensive analysis of the lineage heterogeneity and altered transcriptomic profiles of vascular cells from healthy and aneurysmal mouse CoW using single-cell RNA sequencing. METHODS: Cerebral aneurysms (CAs) were induced in adult male mice using an elastase model. Single-cell RNA sequencing was then performed on CoW samples obtained from animals that either had aneurysms form or rupture 14 days post-induction. Sham-operated animals served as controls. RESULTS: Unbiased clustering analysis of the transcriptional profiles from >3900 CoW cells identified 19 clusters representing ten cell lineages: vascular smooth muscle cells, endothelial cells fibroblasts, pericytes and immune cells (macrophages, T and B lymphocytes, dendritic cells, mast cells, and neutrophils). The 5 vascular smooth muscle cell subpopulations had distinct transcriptional profiles and were classified as proliferative, stress-induced senescent, quiescent, inflammatory-like, or hyperproliferative. The transcriptional signature of the metabolic pathways of ATP generation was found to be downregulated in 2 major vascular smooth muscle cell clusters when CA was induced. Aneurysm induction led to significant expansion of the total macrophage population, and this expansion was further increased with rupture. Both inflammatory and resolution-phase macrophages were identified, and a massive spike of neutrophils was seen with CA rupture. Additionally, the neutrophil-to-lymphocyte ratio (NLR), which originated from CA induction mirrored what happens in humans. CONCLUSIONS: Our data identify CA disease-relevant transcriptional signatures of vascular cells in the CoW and is searchable via a web-based R/shiny interface.

Outcomes after emergency general surgery and trauma care in incarcerated individuals: An EAST multicenter study.

BACKGROUND: The US incarcerates more individuals than any other country. Prisoners are the only population guaranteed health care by the US constitution, but little is known about their surgical needs. This multicenter study aimed to describe the acute care surgery (ACS) needs of incarcerated individuals. METHODS: Twelve centers prospectively identified incarcerated patients evaluated in their emergency department by the ACS service. Centers collected diagnosis, treatment, and complications from chart review. Patients were classified as either emergency general surgery (EGS) patients or trauma patients and their characteristics and outcomes were investigated. Poisson regression accounting for clustering by center was used to calculate the relative risk (RR) of readmission, representation within 90 days, and failure to follow-up as an outpatient within 90 days for each cohort. RESULTS: More than 12 months, ACS services evaluated 943 patients, 726 (80.3%) from jail, 156 (17.3%) from prison, and 22 (2.4%) from other facilities. Most were men (89.7%) with a median age of 35 years (interquartile range, 27-47). Trauma patients comprised 54.4% (n = 513) of the cohort. Admission rates were similar for trauma (61.5%) and EGS patients (60.2%). Head injuries and facial fractures were the most common injuries, while infections were the most common EGS diagnosis. Self-harm resulted in 102 trauma evaluations (19.9%). Self-inflicted injuries were associated with increased risk of readmission (RR, 4.3; 95% confidence interval, 3.02-6.13) and reevaluation within 90 days (RR, 4.96; 95% confidence interval, 3.07-8.01). CONCLUSION: Incarcerated patients who present with a range of trauma and EGS conditions frequently require admission, and follow-up after hospitalization was low at the treating center. Poor follow-up coupled with high rates of assault, self-harm, mental health, and substance use disorders highlight the vulnerability of this population. Hospital and correctional facility interventions are needed to decrease self-inflicted injuries and assaults while incarcerated. LEVEL OF EVIDENCE: Prognostic and epidemiological, Level III.

Eastern Association for the Surgery of Trauma Multicenter Trial: Comparison of pre-injury antithrombotic use and reversal strategies among severe traumatic brain injury patients.

BACKGROUND: Trauma teams are often faced with patients on antithrombotic (AT) drugs, which is challenging when bleeding occurs. We sought to compare the effects of different AT medications on head injury severity and hypothesized that AT reversal would not improve mortality in severe traumatic brain injury (TBI) patients. METHODS: An Eastern Association for the Surgery of Trauma-sponsored prospective, multicentered, observational study of 15 trauma centers was performed. Patient demographics, injury burden, comorbidities, AT agents, and reversal attempts were collected. Outcomes of interest were head injury severity and in-hospital mortality. RESULTS: Analysis was performed on 2,793 patients. The majority of patients were on aspirin (acetylsalicylic acid [ASA], 46.1%). Patients on a platelet chemoreceptor blocker (P2Y12) had the highest mean Injury Severity Score (9.1 ± 8.1). Patients taking P2Y12 inhibitors ± ASA, and ASA-warfarin had the highest head Abbreviated Injury Scale (AIS) mean (1.2 ± 1.6). On risk-adjusted analysis, warfarin-ASA was associated with a higher head AIS (odds ratio [OR], 2.43; 95% confidence interval [CI], 1.34-4.42) after controlling for Injury Severity Score, Charlson Comorbidity Index, initial Glasgow Coma Scale score, and initial systolic blood pressure. Among patients with severe TBI (head AIS score, ≥3) on antiplatelet therapy, reversal with desmopressin (DDAVP) and/or platelet transfusion did not improve survival (82.9% reversal vs. 90.4% none, p = 0.30). In severe TBI patients taking Xa inhibitors who received prothrombin complex concentrate, survival was not improved (84.6% reversal vs. 84.6% none, p = 0.68). With risk adjustment as described previously, mortality was not improved with reversal attempts (antiplatelet agents: OR 0.83; 85% CI, 0.12-5.9 [p = 0.85]; Xa inhibitors: OR, 0.76; 95% CI, 0.12-4.64; p = 0.77). CONCLUSION: Reversal attempts appear to confer no mortality benefit in severe TBI patients on antiplatelet agents or Xa inhibitors. Combination therapy was associated with severity of head injury among patients taking preinjury AT therapy, with ASA-warfarin possessing the greatest risk. LEVEL OF EVIDENCE: Prognostic, level II.

The history of organ transplantation.

Since ancient times, mythology has included tales of creatures made of an amalgamation of others, transferring body parts and skin. In the 1950s, with no other medical options for then incurable diseases, including nephritis, teams of scientists, surgeons, and generous patients started the field of organ transplant with the first successful kidney transplant in a human. The scientific discoveries and innovations since that first successful transplant in 1954 have turned the mythical concept of transplant into reality. The overall success and public acceptance of organ donation and transplant today is thanks to multidisciplinary teams of basic scientists, immunologists, surgeons, and public advocates. Today, research is propelling the field forward with advancements like face transplants, experiments of lab-grown organs, and much more. In the United States alone, over 800,000 patients have had their lives saved or significantly improved thanks to transplant since national recording began by the Organ Procurement and Transplant Network in 1988.

Manganese Acts upon Insulin/IGF Receptors to Phosphorylate AKT and Increase Glucose Uptake in Huntington's Disease Cells.

Perturbations in insulin/IGF signaling and manganese (Mn2+) uptake and signaling have been separately reported in Huntington's disease (HD) models. Insulin/IGF supplementation ameliorates HD phenotypes via upregulation of AKT, a known Mn2+-responsive kinase. Limited evidence both in vivo and in purified biochemical systems suggest Mn2+ enhances insulin/IGF receptor (IR/IGFR), an upstream tyrosine kinase of AKT. Conversely, Mn2+ deficiency impairs insulin release and associated glucose tolerance in vivo. Here, we test the hypothesis that Mn2+-dependent AKT signaling is predominantly mediated by direct Mn2+ activation of the insulin/IGF receptors, and HD-related impairments in insulin/IGF signaling are due to HD genotype-associated deficits in Mn2+ bioavailability. We examined the combined effects of IGF-1 and/or Mn2+ treatments on AKT signaling in multiple HD cellular models. Mn2+ treatment potentiates p-IGFR/IR-dependent AKT phosphorylation under physiological (1 nM) or saturating (10 nM) concentrations of IGF-1 directly at the level of intracellular activation of IGFR/IR. Using a multi-pharmacological approach, we find that > 70-80% of Mn2+-associated AKT signaling across rodent and human neuronal cell models is specifically dependent on IR/IGFR, versus other signaling pathways upstream of AKT activation. Mn2+-induced p-IGFR and p-AKT were diminished in HD cell models, and, consistent with our hypothesis, were rescued by co-treatment of Mn2+ and IGF-1. Lastly, Mn2+-induced IGF signaling can modulate HD-relevant biological processes, as the reduced glucose uptake in HD STHdh cells was partially reversed by Mn2+ supplementation. Our data demonstrate that Mn2+ supplementation increases peak IGFR/IR-induced p-AKT likely via direct effects on IGFR/IR, consistent with its role as a cofactor, and suggests reduced Mn2+ bioavailability contributes to impaired IGF signaling and glucose uptake in HD models.

Acute manganese treatment restores defective autophagic cargo loading in Huntington's disease cell lines.

The molecular etiology linking the pathogenic mutations in the Huntingtin (Htt) gene with Huntington's disease (HD) is unknown. Prior work suggests a role for Htt in neuronal autophagic function and mutant HTT protein disrupts autophagic cargo loading. Reductions in the bioavailability of the essential metal manganese (Mn) are seen in models of HD. Excess cellular Mn impacts autophagic function, but the target and molecular basis of these changes are unknown. Thus, we sought to determine if changes in cellular Mn status impact autophagic processes in a wild-type or mutant Htt-dependent manner. We report that the HD genotype is associated with reduced Mn-induced autophagy and that acute Mn exposure increases autophagosome induction/formation. To determine if a deficit in bioavailable Mn is mechanistically linked to the autophagy-related HD cellular phenotypes, we examined autophagosomes by electron microscopy. We observed that a 24 h 100 uM Mn restoration treatment protocol attenuated an established HD 'cargo-recognition failure' in the STHdh HD model cells by increasing the percentage of filled autophagosomes. Mn restoration had no effect on HTT aggregate number, but a 72 h co-treatment with chloroquine (CQ) in GFP-72Q-expressing HEK293 cells increased the number of visible aggregates in a dose-dependent manner. As CQ prevents autophagic degradation this indicates that Mn restoration in HD cell models facilitates incorporation of aggregates into autophagosomes. Together, these findings suggest that defective Mn homeostasis in HD models is upstream of the impaired autophagic flux and provide proof-of-principle support for increasing bioavailable Mn in HD to restore autophagic function and promote aggregate clearance.

Phosphatidylinositol 3 kinase (PI3K) modulates manganese homeostasis and manganese-induced cell signaling in a murine striatal cell line.

In a recent study, we found that blocking the protein kinase ataxia telangiectasia mutated (ATM) with the small molecule inhibitor (SMI) KU-55933 can completely abrogate Mn-induced phosphorylation of p53 at serine 15 (p-p53) in human induced pluripotent stem cell (hiPSC)-differentiated striatal neuroprogenitors. However, in the immortalized mouse striatal progenitor cell line STHdhQ7/Q7, a concentration of KU55933 far exceeding its IC50 for ATM was required to inhibit Mn-induced p-p53. This suggested an alternative signaling system redundant with ATM kinase for activating p53 in this cell line- one that was altered by KU55933 at these higher concentrations (i.e. mTORC1, DNApk, PI3K). To test the hypothesis that one or more of these signaling pathways contributed to Mn-induced p-p53, we utilized a set of SMIs (e.g. NU7441 and LY294002) known to block DNApk, PI3K, and mTORC1 at distinct concentrations. We found that the SMIs inhibit Mn-induced p-p53 expression near the expected IC50s for PI3K, versus other known targets. We hypothesized that inhibiting PI3K reduces intracellular Mn and thereby decreases activation of p53 by Mn. Using the cellular fura-2 manganese extraction assay (CFMEA), we determined that KU55933/60019, NU7441, and LY294002 (at concentrations near their IC50s for PI3K) all decrease intracellular Mn (∼50%) after a dual, 24-h Mn and SMI exposure. Many pathways are activated by Mn aside from p-p53, including AKT and mTOR pathways. Thus, we explored the activation of these pathways by Mn in STHdh cells as well as the effects of other pathway inhibitors. p-AKT and p-S6 activation by Mn is almost completely blocked upon addition of NU7441(5µM) or LY294002(7µM), supporting PI3K's upstream role in the AKT/mTOR pathway. We also investigated whether PI3K inhibition blocks Mn uptake in other cell lines. LY294002 exposure did not reduce Mn uptake in ST14A, Neuro2A, HEK293, MEF, or hiPSC-derived neuroprogenitors. Next, we sought to determine whether inhibition of PI3K blocked p53 phosphorylation by directly blocking an unknown PI3K/p53 interaction or indirectly reducing intracellular Mn, decreasing p-p53 expression. In-Cell Western and CFMEA experiments using multiple concentrations of Mn exposures demonstrated that intracellular Mn levels directly correlated with p-p53 expression with or without addition of LY294002. Finally, we examined whether PI3K inhibition was able to block Mn-induced p-p53 activity in hiPSC-derived striatal neuroprogenitors. As expected, LY294002 does not block Mn-induced p-p53 as PI3K inhibition is unable to reduce Mn net uptake in this cell line, suggesting the effect of LY294002 on Mn uptake is relatively specific to the STHdh mouse striatal cell line.