Microwave Spectroscopy of Chiral Astrochemical Candidate Vinyloxirane: The Missing Gauche Conformer.

The recent detection of a chiral molecule, propylene oxide, in the interstellar medium provides impetus for investigation of related analogues as candidates for discovery of a second chiral species. Vinyloxirane (VO) shares many of the characteristics of propylene oxide that favored its remote detection such as modest size, appreciable dipole moment and modest adsorption to water ice. The microwave spectrum of vinyloxirane at room temperature has been studied in the 18 - 26 GHz region. Rotational transitions of the previously undetected gauche-1 conformer have been assigned and fitted. The quantum number range of anti conformer transitions has been greatly expanded, providing improved molecular constants. Vibrational satellite transitions were assigned and fitted for the lowest frequency ν27 torsion mode, for 2ν27, and for the ν26 C=CC bend of anti VO, along with ν27 satellites of gauche-1. The rovibrational analyses were assisted by anharmonic vibrational calculations at B3LYP-D3/aug-cc-PVTZ, B2PLYPD3/cc-pVTZ, and DSDPBEP86/cc-pVTZ levels. Experimental peak intensities provide a population ratio Ngauche-1/Nanti of 0.36 ± 0.06, corresponding to a Gibbs free energy difference of 2.5 ± 0.4 kJ mol-1 in favor of the anti conformer, in agreement with the density functional theory results. In the gauche-1 conformer, the torsional angle between vinyl group and oxirane ring, τC=CCM, is optimized at -35° to favor an intramolecular CvinylH11...O interaction. The gauche-2 conformer with τC=CCM of + 74° suffers from CvinylH11...HCcyclopropyl repulsion so that it is calculated to be 8-9 kJ mol-1 higher than gauche-1. Reinterpretation of earlier Raman spectra suggests that the gauche-2 conformer had not been observed as reported.

Weak grip strength among persons with multiple sclerosis having minimal disability is not related to agility or integrity of the corticospinal tract.

INTRODUCTION: Mobility impairment is common in multiple sclerosis (MS); however, agility has received less attention. Agility requires strength and neuromuscular coordination to elicit controlled propulsive rapid whole-body movement. Grip strength is a common method to assess whole body force production, but also reflects neuromuscular integrity and global brain health. Impaired agility may be linked to loss of neuromuscular integrity (reflected by grip strength or corticospinal excitability). OBJECTIVES: We aimed to determine whether grip strength would be associated with agility and transcranial magnetic stimulation (TMS)-based indices of corticospinal excitability and inhibition in persons with MS having low disability. We hypothesized that low grip strength would predict impaired agility and reflect low corticospinal excitability. METHODS: We recruited 34 persons with relapsing MS (27 females; median [range] age 45.5 [21.0-65.0] years) and mild disability (median [range] Expanded Disability Status Scale 2.0 [0-3.0]), as well as a convenience sample of age- and sex-matched apparently healthy controls. Agility was tested by measuring hop length during bipedal hopping on an instrumented walkway. Grip strength was measured using a calibrated dynamometer. Corticospinal excitability and inhibition were examined using TMS-based motor evoked potential (MEP) and corticospinal silent period (CSP) recruitment curves, respectively. RESULTS: MS participants had significantly lower grip strength than controls independent of sex. Females with and without MS had weaker grip strength than males. There were no statistically significant sex or group differences in agility. After controlling for sex, weaker grip strength was associated with shorter hop length in controls only (r = 0.645, p < .05). Grip strength did not significantly predict agility in persons with MS, nor was grip strength predicted by corticospinal excitability or inhibition. CONCLUSIONS: In persons with MS having low disability, grip strength (normalized to body mass) was reduced despite having intact agility and walking performance. Grip strength was not associated with corticospinal excitability or inhibition, suggesting peripheral neuromuscular function, low physical activity or fitness, or other psychosocial factors may be related to weakness. Low grip strength is a putative indicator of early neuromuscular aging in persons with MS having mild disability and normal mobility.

Elucidating the Mechanism of Efficient Eu(III) and Yb(III) Sensitisation from a Re(I) Tetrazolato Triangular Assembly.

The reaction of Re(CO)5Br with deprotonated 1H-(5-(2,2':6',2''-terpyridine)pyrid-2-yl)tetrazole yields a triangular assembly formed by tricarbonyl Re(I) vertices. Photophysical measurements reveal blue-green emission with a maximum at 520 nm, 32% quantum yield, and 2430 ns long-lived excited state decay lifetime in deaerated dichloromethane solution. Coordination of lanthanoid ions to the terpyridine units red-shifts the emission to 570 nm and also reveals efficient (90%) and fast sensitisation to both Eu(III) and Yb(III) at room temperature, with a similar rate constant kET of the order of 107 s-1. Efficient sensitisation of Eu(III) from Re(I) is unprecedented, especially when considering the close proximity in energy between the donor and acceptor excited states. On the other hand, comparative measurements at 77 K reveal that energy transfer to Yb(III) is two orders of magnitude slower than that to Eu(III). A two-step mechanism of sensitisation is therefore proposed, whereby the rate-determining step is a thermally activated energy transfer step between the Re(I) centre and the terpyridine functionality, followed by rapid energy transfer to the respective Ln(III) excited states. At 77 K, the direct Re(I) to Eu(III) energy transfer seems to proceed via a ligand-mediated superexchange Dexter-type mechanism.

The impact of post-operative enteral nutrition on duodenal injury outcomes: A post hoc analysis of an EAST multicenter trial.

BACKGROUND: Leak following surgical repair of traumatic duodenal injuries results in prolonged hospitalization and oftentimes nil per os(NPO) treatment. Parenteral nutrition(PN) has known morbidity; however, duodenal leak(DL) patients often have complex injuries and hospital courses resulting in barriers to enteral nutrition(EN). We hypothesized EN alone would be associated with 1)shorter duration until leak closure and 2)less infectious complications and shorter hospital length of stay(HLOS) compared to PN. METHODS: This was a post-hoc analysis of a retrospective, multicenter study from 35 Level-1 trauma centers, including patients >14 years-old who underwent surgery for duodenal injuries(1/2010-12/2020) and endured post-operative DL. The study compared nutrition strategies: EN vs PN vs EN + PN using Chi-Square and Kruskal-Wallis tests; if significance was found pairwise comparison or Dunn's test were performed. RESULTS: There were 113 patients with DL: 43 EN, 22 PN, and 48 EN + PN. Patients were young(median age 28 years-old) males(83.2%) with penetrating injuries(81.4%). There was no difference in injury severity or critical illness among the groups, however there were more pancreatic injuries among PN groups. EN patients had less days NPO compared to both PN groups(12 days[IQR23] vs 40[54] vs 33[32],p = <0.001). Time until leak closure was less in EN patients when comparing the three groups(7 days[IQR14.5] vs 15[20.5] vs 25.5[55.8],p = 0.008). EN patients had less intra-abdominal abscesses, bacteremia, and days with drains than the PN groups(all p < 0.05). HLOS was shorter among EN patients vs both PN groups(27 days[24] vs 44[62] vs 45[31],p = 0.001). When controlling for predictors of leak, regression analysis demonstrated EN was associated with shorter HLOS(ß -24.9, 95%CI -39.0 to -10.7,p < 0.001). CONCLUSION: EN was associated with a shorter duration until leak closure, less infectious complications, and shorter length of stay. Contrary to some conventional thought, PN was not associated with decreased time until leak closure. We therefore suggest EN should be the preferred choice of nutrition in patients with duodenal leaks whenever feasible. LEVEL OF EVIDENCE: IV.

A multi-institutional meningioma MRI dataset for automated multi-sequence image segmentation.

Meningiomas are the most common primary intracranial tumors and can be associated with significant morbidity and mortality. Radiologists, neurosurgeons, neuro-oncologists, and radiation oncologists rely on brain MRI for diagnosis, treatment planning, and longitudinal treatment monitoring. However, automated, objective, and quantitative tools for non-invasive assessment of meningiomas on multi-sequence MR images are not available. Here we present the BraTS Pre-operative Meningioma Dataset, as the largest multi-institutional expert annotated multilabel meningioma multi-sequence MR image dataset to date. This dataset includes 1,141 multi-sequence MR images from six sites, each with four structural MRI sequences (T2-, T2/FLAIR-, pre-contrast T1-, and post-contrast T1-weighted) accompanied by expert manually refined segmentations of three distinct meningioma sub-compartments: enhancing tumor, non-enhancing tumor, and surrounding non-enhancing T2/FLAIR hyperintensity. Basic demographic data are provided including age at time of initial imaging, sex, and CNS WHO grade. The goal of releasing this dataset is to facilitate the development of automated computational methods for meningioma segmentation and expedite their incorporation into clinical practice, ultimately targeting improvement in the care of meningioma patients.

The Brain's Sensitivity to Real-world Statistical Regularity Does Not Require Full Attention.

Predictive coding accounts of perception state that the brain generates perceptual predictions in the service of processing incoming sensory data. These predictions are hypothesized to be afforded by the brain's ability to internalize useful patterns, that is, statistical regularities, from the environment. We have previously argued that the N300 ERP component serves as an index of the brain's use of representations of (real-world) statistical regularities. However, we do not yet know whether overt attention is necessary in order for this process to engage. We addressed this question by presenting stimuli of either high or low real-world statistical regularity in terms of their representativeness (good/bad exemplars of natural scene categories) to participants who either fully attended the stimuli or were distracted by another task (attended/distracted conditions). Replicating past work, N300 responses were larger to bad than to good scene exemplars, and furthermore, we demonstrate minimal impacts of distraction on N300 effects. Thus, it seems that overtly focused attention is not required to maintain the brain's sensitivity to real-world statistical regularity. Furthermore, in an exploratory analysis, we showed that providing additional, artificial regularities, formed by altering the proportions of good and bad exemplars within blocks, further enhanced the N300 effect in both attended and distracted conditions, shedding light on the relationship between statistical regularities learned in the real world and those learned within the context of an experiment.

Blood Management in a Liver Transplant Recipient with Kidd (Jka) and Rhesus (D) Antibodies: A Case Report.

A 67-year-old man presented for urgent liver transplantation (LT). Screening revealed the rare combination of antiRhesus (D) and antiKidd Jk(a) antibodies, requiring antigen-negative red blood cells (RBC) for both phenotypes. This combination has not been reported during LT. Compatible RBCs were initially limited, requiring continued communication between the blood bank/blood supplier to obtain more, including frozen, units. Additional strategies included the use of cell salvage and intentional management of coagulopathy to limit bleeding and RBC requirement. This case highlights blood management during LT when D and Jk(a) antibodies may limit RBC supply and emphasizes the need for effective communication with the blood bank.

Bypassing input to V1 in visual awareness: A TMS-EROS investigation.

Early visual cortex (V1-V3) is believed to be critical for normal visual awareness by providing the necessary feedforward input. However, it remains unclear whether visual awareness can occur without further involvement of early visual cortex, such as re-entrant feedback. It has been challenging to determine the importance of feedback activity to these areas because of the difficulties in dissociating this activity from the initial feedforward activity. Here, we applied single-pulse transcranial magnetic stimulation (TMS) over the left posterior parietal cortex to elicit phosphenes in the absence of direct visual input to early visual cortex. Immediate neural activity after the TMS pulse was assessed using the event-related optical signal (EROS), which can measure activity under the TMS coil without artifacts. Our results show that: 1) The activity in posterior parietal cortex 50 ms after TMS was related to phosphene awareness, and 2) Activity related to awareness was observed in a small portion of V1 140 ms after TMS, but in contrast (3) Activity in V2 was a more robust correlate of awareness. Together, these results are consistent with interactive models proposing that sustained and recurrent loops of activity between cortical areas are necessary for visual awareness to emerge. In addition, we observed phosphene-related activations of the anteromedial cuneus and lateral occipital cortex, suggesting a functional network subserving awareness comprising these regions, the parietal cortex and early visual cortex.

Predictors of clinical deterioration and intensive care unit admission in trauma patients transferred from northern Quebec to a level 1 trauma centre: a retrospective cohort study.

BACKGROUND: Trauma care in Nunavik, Quebec, is highly challenging. Geographic distances and delays in transport can translate into precarious patient transfers to tertiary trauma care centres. The objective of this study was to identify predictors of clinical deterioration during transport and eventual intensive care unit (ICU) admission for trauma patients transferred from Nunavik to a tertiary trauma care centre. METHODS: This is a retrospective cohort study using the Montreal General Hospital (MGH) trauma registry. All adult trauma patients transferred from Nunavik and admitted to the MGH from 2010 to 2019 were included. Main outcomes of interest were hemodynamic and neurologic deterioration during transport and ICU admission. RESULTS: In total, 704 patients were transferred from Nunavik and admitted to the MGH during the study period. The median age was 33 (interquartile range [IQR] 23-47) years and the median Injury Severity Score was 10 (IQR 5-17). On multiple regression analysis, transport time from site of injury to the MGH (odds ratio [OR] 1.04, 95% confidence interval [CI] 1.01-1.06), thoracic injuries (OR 1.75, 95% CI 1.03-2.99), and head and neck injuries (OR 3.76, 95% CI 2.10-6.76) predicted clinical deterioration during transfer. Injury Severity Score (OR 1.04, 95% CI 1.01-1.08), abnormal local Glasgow Coma Scale score (OR 2.57, 95% CI 1.34-4.95), clinical deterioration during transfer (OR 4.22, 95% CI 1.99-8.93), traumatic brain injury (OR 2.44, 95% CI 1.05-5.68), and transfusion requirement at the MGH (OR 4.63, 95% CI 2.35-9.09) were independent predictors of ICU admission. CONCLUSION: Our study identified several predictors of clinical deterioration during transfer and eventual ICU admission for trauma patients transferred from Nunavik. These factors could be used to refine triage criteria in Nunavik for more timely evacuation and higher level care during transport.

Continuous-wave cavity ringdown for high-sensitivity polarimetry and magnetometry measurements.

We report the development of a novel variant of cavity ringdown polarimetry using a continuous-wave laser operating at 532 nm for highly precise chiroptical activity and magnetometry measurements. The key methodology of the apparatus relies upon the external modulation of the laser frequency at the frequency splitting between non-degenerate left- and right-circularly polarized cavity modes. The method is demonstrated by the evaluation of the Verdet constants of crystalline CeF3 and fused silica, in addition to the observation of gas- and solution-phase optical rotations of selected chiral molecules. Specifically, optical rotations of (i) vapors of α-pinene and R-(+)-limonene, (ii) mutarotating D-glucose in water, and (iii) acidified L-histidine solutions are determined. The detection sensitivities for the gas- and solution-phase chiral activity measurements are ∼30 and ∼120µdeg over a 30 s detection period per cavity round trip pass, respectively. Furthermore, the measured optical rotations for R-(+)-limonene are compared with computations performed using the TURBOMOLE quantum chemistry package. The experimentally observed optically rotatory dispersion of this cyclic monoterpene was thus rationalized via a consideration of its room temperature conformer distribution as determined by the aforementioned single-point energy calculations.

The Impact of Smoking on Hospital Course and Postoperative Outcomes in Patients With Fracture-Related Infections.

OBJECTIVES: To assess the relationship between patient smoking status and fracture-related infection (FRI) characteristics including patient symptoms at FRI presentation, bacterial species of FRI, and rates of fracture union. DESIGN: Retrospective cohort study. SETTING: Urban level 1 trauma center. PATIENT SELECTION CRITERIA: All patients undergoing reoperation for FRI from January 2013 to April 2021 were identified through manual review of an institutional database. OUTCOME MEASURES AND COMPARISONS: Data including patient demographics, fracture characteristics, infection presentation, and hospital course were collected through review of the electronic medical record. Patients were grouped based on current smoker versus nonsmoker status. Hospital course and postoperative outcomes of these groups were then compared. Risk factors of methicillin-resistant Staphylococcus aureus (MRSA) infection, Staphylococcus epidermidis infection, and sinus tract development were evaluated using multivariable logistic regression. RESULTS: A total of 301 patients, comprising 155 smokers (51%) and 146 nonsmokers (49%), undergoing FRI reoperation were included. Compared with nonsmokers, smokers were more likely male (69% vs. 56%, P = 0.024), were younger at the time of FRI reoperation (41.7 vs. 49.5 years, P < 0.001), and had lower mean body mass index (27.2 vs. 32.0, P < 0.001). Smokers also had lower prevalence of diabetes mellitus (13% vs. 25%, P = 0.008) and had higher Charlson Comorbidity Index 10-year estimated survival (93% vs. 81%, P < 0.001). Smokers had a lower proportion of S. epidermidis infections (11% vs. 20%, P = 0.037), higher risk of nonunion after index fracture surgery (74% vs. 61%, P = 0.018), and higher risk of sinus tracts at FRI presentation (38% vs. 23%, P = 0.004). On multivariable analysis, smoking was not found to be associated with increased odds of MRSA infection. CONCLUSIONS: Among patients who develop a FRI, smokers seemed to have better baseline health regarding age, body mass index, diabetes mellitus, and Charlson Comorbidity Index 10-year estimated survival compared with nonsmokers. Smoking status was not significantly associated with odds of MRSA infection. However, smoking status was associated with increased risk of sinus tract development and nonunion and lower rates of S. epidermidis infection at the time of FRI reoperation. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Extraislet expression of islet antigen boosts T cell exhaustion to partially prevent autoimmune diabetes.

Persistent antigen exposure results in the differentiation of functionally impaired, also termed exhausted, T cells which are maintained by a distinct population of precursors of exhausted T (TPEX) cells. T cell exhaustion is well studied in the context of chronic viral infections and cancer, but it is unclear whether and how antigen-driven T cell exhaustion controls progression of autoimmune diabetes and whether this process can be harnessed to prevent diabetes. Using nonobese diabetic (NOD) mice, we show that some CD8+ T cells specific for the islet antigen, islet-specific glucose-6-phosphatase catalytic subunit-related protein (IGRP) displayed terminal exhaustion characteristics within pancreatic islets but were maintained in the TPEX cell state in peripheral lymphoid organs (PLO). More IGRP-specific T cells resided in the PLO than in islets. To examine the impact of extraislet antigen exposure on T cell exhaustion in diabetes, we generated transgenic NOD mice with inducible IGRP expression in peripheral antigen-presenting cells. Antigen exposure in the extraislet environment induced severely exhausted IGRP-specific T cells with reduced ability to produce interferon (IFN)γ, which protected these mice from diabetes. Our data demonstrate that T cell exhaustion induced by delivery of antigen can be harnessed to prevent autoimmune diabetes.

Vascular access complications associated with resuscitative endovascular balloon occlusion of the aorta in adult trauma patients: A systematic review and meta-analysis.

BACKGROUND: Resuscitative endovascular balloon occlusion of the aorta (REBOA) is gaining popularity worldwide for managing hypotensive trauma patients. Vascular access complications related to REBOA placement have been reported, with some cases resulting in permanent morbidity. We aim to capitalize on the increase in literature to further describe and estimate the incidence of REBOA-associated vascular access complications in adult trauma patients. METHODS: We searched Medline, EMBASE, Scopus, and CINAHL for studies reporting vascular access complications of REBOA in adult trauma patients from inception to October 14, 2021. Studies reporting data from adult trauma patients who underwent REBOA insertion were eligible. Exclusion criteria included patients 15 years and younger, nontrauma patients, non-REBOA use, non-vascular access complications and patient duplication. Study data was abstracted using the PRISMA checklist and verified independently by three reviewers. Meta-analysis of proportions was performed using a random effects model with Freeman-Turkey double-arcsine transformation. Post hoc meta-regression by year of publication, sheath-size, and geographic region was also performed. The incidence of vascular access complications from REBOA insertion was the primary outcome of interest. Subgroup analysis was performed by degree of bias, sheath size, technique of vascular access, provider specialty, geographical region, and publication year. RESULTS: Twenty-four articles were included in the systematic review and the meta-analysis, for a total of 675 trauma patients who underwent REBOA insertion. The incidence of vascular access complications was 8% (95% confidence interval, 5%-13%). In post hoc meta-regression adjusting for year of publication and geographic region, the use of a smaller (7-Fr) sheath was associated with a decreased incidence of vascular access complications (odds ratio, 0.87; 95% confidence interval, 0.75-0.99; p = 0.046; R 2 = 35%; I 2 = 48%). CONCLUSION: This study provides a benchmark for quality of care in terms of vascular access complications related to REBOA insertion in adult trauma patients. Smaller sheath size may be associated with a decrease in vascular access complications. LEVEL OF EVIDENCE: Systematic Review and Meta-Analysis; Level III.

Genetic variation influences the skeletal response to hindlimb unloading in the eight founder strains of the diversity outbred mouse population.

During disuse, mechanical unloading causes extensive bone loss, decreasing bone volume and strength. Variations in bone mass and risk of osteoporosis are influenced by genetics; however, it remains unclear how genetic variation affects the skeletal response to unloading. We previously found that genetic variation affects the musculoskeletal response to 3 weeks of immobilization in the 8 Jackson Laboratory J:DO founder strains: C57Bl/6J, A/J, 129S1/SvImJ, NOD/ShiLtJ, NZO/HlLtJ, CAST/EiJ, PWK/PhJ, and WSB/EiJ. Hindlimb unloading (HLU) is the best model for simulating local and systemic contributors of disuse and therefore may have a greater impact on bones than immobilization. We hypothesized that genetic variation would affect the response to HLU across the eight founder strains. Mice of each founder strain were placed in HLU for 3 weeks, and the femurs and tibias were analyzed. There were significant HLU and mouse strain interactions on body weight, femur trabecular BV/TV, and femur ultimate force. This indicates that unloading only caused significant catabolic effects in some mouse strains. C57BL/6 J mice were most affected by unloading while other strains were more protected. There were significant HLU and mouse strain interactions on gene expression of genes encoding bone metabolism genes in the tibia. This indicates that unloading only caused significant effects on bone metabolism genes in some mouse strains. Different mouse strains respond to HLU differently, and this can be explained by genetic differences. These results suggest the outbred J:DO mice will be a powerful model for examining the effects of genetics on the skeletal response to HLU.

A molecular switch for neuroprotective astrocyte reactivity.

The intrinsic mechanisms that regulate neurotoxic versus neuroprotective astrocyte phenotypes and their effects on central nervous system degeneration and repair remain poorly understood. Here we show that injured white matter astrocytes differentiate into two distinct C3-positive and C3-negative reactive populations, previously simplified as neurotoxic (A1) and neuroprotective (A2)1,2, which can be further subdivided into unique subpopulations defined by proliferation and differential gene expression signatures. We find the balance of neurotoxic versus neuroprotective astrocytes is regulated by discrete pools of compartmented cyclic adenosine monophosphate derived from soluble adenylyl cyclase and show that proliferating neuroprotective astrocytes inhibit microglial activation and downstream neurotoxic astrocyte differentiation to promote retinal ganglion cell survival. Finally, we report a new, therapeutically tractable viral vector to specifically target optic nerve head astrocytes and show that raising nuclear or depleting cytoplasmic cyclic AMP in reactive astrocytes inhibits deleterious microglial or macrophage cell activation and promotes retinal ganglion cell survival after optic nerve injury. Thus, soluble adenylyl cyclase and compartmented, nuclear- and cytoplasmic-localized cyclic adenosine monophosphate in reactive astrocytes act as a molecular switch for neuroprotective astrocyte reactivity that can be targeted to inhibit microglial activation and neurotoxic astrocyte differentiation to therapeutic effect. These data expand on and define new reactive astrocyte subtypes and represent a step towards the development of gliotherapeutics for the treatment of glaucoma and other optic neuropathies.

Postoperative Cerebrospinal Fluid-Related Complications After Posterior Fossa and Posterolateral Skull Base Surgeries: Development of a Predictive Model and Clinical Risk Score.

BACKGROUND: Postoperative pseudomeningocele (PMC) and cerebrospinal fluid (CSF) leak are common complications following posterior fossa and posterolateral skull base surgeries. We sought to 1) determine the rate of CSF-related complications and 2) develop a perioperative model and risk score to identify the highest risk patients for these events. METHODS: We performed a retrospective cohort of 450 patients undergoing posterior fossa and posterolateral skull base procedures from 2016 to 2020. Logistic regressions were performed for predictor selection for 3 prespecified models: 1) a priori variables, 2) predictors selected by large effect sizes, and 3) predictors with P ≤ 0.100 on univariable analysis. A final model was created by elimination of nonsignificant predictors, and the integer-based postoperative CSF-related complications (POCC) clinical risk score was derived. Internal validation was done using 10-fold cross-validation and bootstrapping with uniform shrinkage. RESULTS: A total of 115 patients (25.6%) developed PMC and/or CSF leakage. Age >55 years (odds ratio [OR], 0.560; 95% confidence interval [CI], 0.328-0.954), body mass index >30 kg/m2 (OR, 1.88; 95% CI, 1.14-3.10), and postoperative CSF diversion (OR, 2.85; 95% CI, 1.64-5.00) were associated with CSF leak and PMC. Model 2 was the most predictive (cross-validated area under the receiver operating characteristic curve, 0.690). The final risk score was devised using age, body mass index class, dural repair technique, use of bone substitute, and duration of postoperative CSF diversion. The POCC score performed well (cross-validated area under the receiver operating characteristic curve, 0.761) and was highly specific (96.1%). CONCLUSIONS: We created the first generalizable and predictive risk score to identify patients at risk of CSF-related complications. The POCC score could improve surveillance, inform doctor-patient discussions regarding the risks of surgery, and assist in perioperative management.

Empiric Cryoprecipitate Transfusion in Patients with Severe Hemorrhage: Results from the US Experience in the International CRYOSTAT-2 Trial.

BACKGROUND: Hypofibrinogenemia has been shown to predict massive transfusion and is associated with higher mortality in severely injured patients. However, the role of empiric fibrinogen replacement in bleeding trauma patients remains controversial. We sought to determine the effect of empiric cryoprecipitate as an adjunct to a balanced transfusion strategy (1:1:1). STUDY DESIGN: This study is a subanalysis of patients treated at the single US trauma center in a multicenter randomized controlled trial. Trauma patients (more than 15 years) were eligible if they had evidence of active hemorrhage requiring emergent surgery or interventional radiology, massive transfusion protocol (MTP) activation, and received at least 1 unit of blood. Transfer patients, those with injuries incompatible with life, or those injured more than 3 hours earlier were excluded. Patients were randomized to standard MTP (STANDARD) or MTP plus 3 pools of cryoprecipitate (CRYO). Primary outcomes included all-cause mortality at 28 days. Secondary outcomes were transfusion requirements, intraoperative and postoperative coagulation laboratory values, and quality-of-life measures (Glasgow outcome score-extended). RESULTS: Forty-nine patients (23 in the CRYO group and 26 in the STANDARD group) were enrolled between May 2021 and October 2021. Time to randomization was similar between groups (14 vs 24 minutes, p = 0.676). Median time to cryoprecipitate was 41 minutes (interquartile range 37 to 48). There were no differences in demographics, arrival physiology, laboratory values, or injury severity. Intraoperative and ICU thrombelastography values, including functional fibrinogen, were similar between groups. There was no benefit to CRYO with respect to post-emergency department transfusions (intraoperative and ICU through 24 hours), complications, Glasgow outcome score, or mortality. CONCLUSIONS: In this study of severely injured, bleeding trauma patients, empiric cryoprecipitate did not improve survival or reduce transfusion requirements. Cryoprecipitate should continue as an "on-demand" addition to a balanced transfusion strategy, guided by laboratory values and should not be given empirically.

Genetic diversity modulates the physical and transcriptomic response of skeletal muscle to simulated microgravity in male mice.

Developments in long-term space exploration necessitate advancements in countermeasures against microgravity-induced skeletal muscle loss. Astronaut data shows considerable variation in muscle loss in response to microgravity. Previous experiments suggest that genetic background influences the skeletal muscle response to unloading, but no in-depth analysis of genetic expression has been performed. Here, we placed eight, male, inbred founder strains of the diversity outbred mice (129S1/SvImJ, A/J, C57BL/6J, CAST/EiJ, NOD/ShiLtJ, NZO/HILtJ, PWK/PhJ, and WSB/EiJ) in simulated microgravity (SM) via hindlimb unloading for three weeks. Body weight, muscle morphology, muscle strength, protein synthesis marker expression, and RNA expression were collected. A/J and CAST/EiJ mice were most susceptible to SM-induced muscle loss, whereas NOD/ShiLtJ mice were the most protected. In response to SM, A/J and CAST/EiJ mice experienced reductions in body weight, muscle mass, muscle volume, and muscle cross-sectional area. A/J mice had the highest number of differentially expressed genes (68) and associated gene ontologies (328). Downregulation of immunological gene ontologies and genes encoding anabolic immune factors suggest that immune dysregulation contributes to the response of A/J mice to SM. Several muscle properties showed significant interactions between SM and mouse strain and a high degree of heritability. These data imply that genetic background plays a role in the degree of muscle loss in SM and that more individualized programs should be developed for astronauts to protect their skeletal muscles against microgravity on long-term missions.