The p21+ perinecrotic hepatocytes produce the chemokine CXCL14 after a severe acetaminophen overdose promoting hepatocyte injury and delaying regeneration.

Fifty percent of all acute liver failure (ALF) cases in the United States are due to acetaminophen (APAP) overdose. Assessment of canonical features of liver injury, such as plasma alanine aminotransferase activities are poor predictors of acute liver failure (ALF), suggesting the involvement of additional mechanisms independent of hepatocyte death. Previous work demonstrated a severe overdose of APAP results in impaired regeneration, the induction of senescence by p21, and increased mortality. We hypothesized that a discrete population of p21+ hepatocytes acquired a secretory phenotype that directly impedes liver recovery after a severe APAP overdose. Leveraging in-house human APAP explant liver and publicly available single-nuclei RNAseq data, we identified a subpopulation of p21+ hepatocytes enriched in a unique secretome of factors, such as CXCL14. Spatial transcriptomics in the mouse model of APAP overdose confirmed the presence of a p21+ hepatocyte population that directly surrounded the necrotic areas. In both male and female mice, we found a dose-dependent induction of p21 and persistent circulating levels of the p21-specific constituent, CXCL14, in the plasma after a severe APAP overdose. In parallel experiments, we targeted either the putative senescent hepatocytes with the senolytic drugs, dasatinib and quercetin, or CXCL14 with a neutralizing antibody. We found that targeting CXCL14 greatly enhanced liver recovery after APAP-induced liver injury, while targeting senescent hepatocytes had no effect. These data support the conclusion that the sustained induction of p21 in hepatocytes with persistent CXCL14 secretion are critical mechanistic events leading to ALF in mice and human patients.

Principal component analysis of a swine injury model identifies multiple phenotypes in trauma.

BACKGROUND: Trauma is the third leading cause of death in the United States and the primary cause of death for people between the ages of 1 year and 44 years. In addition to tissue damage, trauma may also activate an inflammatory state known as trauma-induced coagulopathy (TIC) that is associated with clotting malfunctions, acidemia, and end-organ dysfunction. Prior work has also demonstrated benefit to acknowledging the type and severity of endothelial injury, coagulation derangements, and systemic inflammation in the management of trauma patients. This study builds upon prior work by combining laboratory, metabolic, and clinical metrics into an analysis of trauma phenotypes, evolution of phenotypes over time after trauma, and significance of trauma phenotype on mortality. METHODS: Seventy 3-month-old female Yorkshire crossbred swine were randomized to injury and resuscitation groups. Principal component analysis (PCA) of longitudinal swine TEG data (Reaction time, Alpha-Angle, Maximum Amplitude, and Clot Lysis at 30 minutes), pH, lactate, and MAP was completed in R at baseline, 1 hour postinjury, 3 hours postinjury, 6 hours postinjury, and 12 hours postinjury. Subjects were compared by principal component factor scores to assess differences in survival, injury severity, and treatment group. RESULTS: Among injured animals, three phenotypes were observed at each time point. Five phenotypes were associated with differences in survival, and of these, four were associated with differences in injury severity. Phenotype alignment was not significantly different by treatment group. CONCLUSION: This application of PCA to a set of coagulation, hemodynamic, and organ perfusion variables has identified multiple evolving phenotypes after trauma. Some of these phenotypes may correlate with injury severity and may have implications for survival. Next steps include validating these findings over greater numbers of subjects and exploring other machine-learning techniques for phenotype identification. LEVEL OF EVIDENCE: Level IV, Therapeutic/Care Management.

Evolution of Partial Resistance to Artemisinins in Malaria Parasites in Uganda.

BACKGROUND: Partial resistance of Plasmodium falciparum to the artemisinin component of artemisinin-based combination therapies, the most important malaria drugs, emerged in Southeast Asia and now threatens East Africa. Partial resistance, which manifests as delayed clearance after therapy, is mediated principally by mutations in the kelch protein K13 (PfK13). Limited longitudinal data are available on the emergence and spread of artemisinin resistance in Africa. METHODS: We performed annual surveillance among patients who presented with uncomplicated malaria at 10 to 16 sites across Uganda from 2016 through 2022. We sequenced the gene encoding kelch 13 (pfk13) and analyzed relatedness using molecular methods. We assessed malaria metrics longitudinally in eight Ugandan districts from 2014 through 2021. RESULTS: By 2021-2022, the prevalence of parasites with validated or candidate resistance markers reached more than 20% in 11 of the 16 districts where surveillance was conducted. The PfK13 469Y and 675V mutations were seen in far northern Uganda in 2016-2017 and increased and spread thereafter, reaching a combined prevalence of 10 to 54% across much of northern Uganda, with spread to other regions. The 469F mutation reached a prevalence of 38 to 40% in one district in southwestern Uganda in 2021-2022. The 561H mutation, previously described in Rwanda, was first seen in southwestern Uganda in 2021, reaching a prevalence of 23% by 2022. The 441L mutation reached a prevalence of 12 to 23% in three districts in western Uganda in 2022. Genetic analysis indicated local emergence of mutant parasites independent of those in Southeast Asia. The emergence of resistance was observed predominantly in areas where effective malaria control had been discontinued or transmission was unstable. CONCLUSIONS: Data from Uganda showed the emergence of partial resistance to artemisinins in multiple geographic locations, with increasing prevalence and regional spread over time. (Funded by the National Institutes of Health.).

How Do Standing Neutral, Supine Lateral, Standing Flexion, and Standing Extension Radiographs Compare in Detecting the Presence and Magnitude of Stable and Dynamic Spondylolisthesis?

BACKGROUND: Clinical guidelines recommend standing radiographs as the most appropriate imaging for detecting degenerative spondylolisthesis, although reliable evidence about the standing position is absent. To our knowledge, no studies have compared different radiographic views and pairings to detect the presence and magnitude of stable and dynamic spondylolisthesis. QUESTIONS/PURPOSES: (1) What is the percentage of new patients presenting with back or leg pain with stable (3 mm or greater listhesis on standing radiographs) and dynamic (3 mm or greater listhesis difference on standing-supine radiographs) spondylolisthesis? (2) What is the difference in the magnitude of spondylolisthesis between standing and supine radiographs? (3) What is the difference in the magnitude of dynamic translation among flexion-extension, standing-supine, and flexion-supine radiographic pairs? METHODS: This cross-sectional, diagnostic study was performed at an urban, academic institution between September 2010 and July 2016; 579 patients 40 years or older received a standard radiographic three-view series (standing AP, standing lateral, and supine lateral radiographs) at a new patient visit. Of those individuals, 89% (518 of 579) did not have any of the following: history of spinal surgery, evidence of vertebral fracture, scoliosis greater than 30°, or poor image quality. In the absence of a reliable diagnosis of dynamic spondylolisthesis using this three-view series, patients may have had flexion and extension radiographs, and approximately 6% (31 of 518) had flexion and extension radiographs. A total of 53% (272 of 518) of patients were female, and the patients had a mean age of 60 ± 11 years. Listhesis distance (in mm) was measured by two raters as displacement of the posterior surface of the superior vertebral body in relation to the posterior surface of the inferior vertebral body from L1 to S1; interrater and intrarater reliability, assessed with intraclass correlation coefficients, was 0.91 and 0.86 to 0.95, respectively. The percentage of patients with and the magnitude of stable spondylolisthesis was estimated on and compared between standing neutral and supine lateral radiographs. The ability of common pairs of radiographs (flexion-extension, standing-supine, and flexion-supine) to detect dynamic spondylolisthesis was assessed. No single radiographic view or pair was considered the gold standard because stable or dynamic listhesis on any radiographic view is often considered positive in clinical practice. RESULTS: Among 518 patients, the percentage of patients with spondylolisthesis was 40% (95% CI 36% to 44%) on standing radiographs alone, and the percentage of patients with dynamic spondylolisthesis was 11% (95% CI 8% to 13%) on the standing-supine pair. Standing radiographs detected greater listhesis than supine radiographs did (6.5 ± 3.9 mm versus 4.9 ± 3.8 mm, difference 1.7 mm [95% CI 1.2 to 2.1 mm]; p < 0.001). Among 31 patients, no single radiographic pairing identified all patients with dynamic spondylolisthesis. The listhesis difference detected between flexion-extension was no different from the listhesis difference detected between standing-supine (1.8 ± 1.7 mm versus 2.0 ± 2.2 mm, difference 0.2 mm [95% CI -0.5 to 1.0 mm]; p = 0.53) and flexion-supine (1.8 ± 1.7 mm versus 2.5 ± 2.2 mm, difference 0.7 mm [95% CI 0.0 to 1.5]; p = 0.06). CONCLUSION: This study supports current clinical guidelines that lateral radiographs should be obtained with patients in the standing position, because all cases of stable spondylolisthesis of 3 mm or greater were detected on standing radiographs alone. Each radiographic pair did not detect different magnitudes of listhesis, and no single pair detected all cases of dynamic spondylolisthesis. Clinical concern for dynamic spondylolisthesis may justify standing neutral, supine lateral, standing flexion, and standing extension views. Future studies could identify and evaluate a set of radiographic views that provides the greatest capacity to diagnose stable and dynamic spondylolisthesis. LEVEL OF EVIDENCE: Level III, diagnostic study.

Dose-dependent pleiotropic role of neutrophils during acetaminophen-induced liver injury in male and female mice.

Acetaminophen (APAP) overdose is the leading cause of acute liver failure in western countries. APAP can cause extensive hepatocellular necrosis, which triggers an inflammatory response involving neutrophil and monocyte recruitment. Particularly the role of neutrophils in the injury mechanism of APAP hepatotoxicity has been highly controversial. Thus, the objective of the current study was to assess whether a potential contribution of neutrophils was dependent on the APAP dose and the sex of the animals. Male and female C57BL/6 J mice were treated with 300 or 600 mg/kg APAP and the injury and inflammatory cell recruitment was evaluated between 6 and 48 h. In both male and female mice, ALT plasma levels and the areas of necrosis peaked at 12-24 h after both doses with more severe injury at the higher dose. In addition, Ly6g-positive neutrophils started to accumulate in the liver at 6 h and peaked at 6-12 h after 300 mg/kg and 12-24 h after 600 mg/kg for both sexes; however, the absolute numbers of hepatic neutrophils in the liver were significantly higher after the 600 mg/kg dose. Neutrophil infiltration correlated with mRNA levels of the neutrophil chemoattractant Cxcl2 in the liver. Treating mice with an anti-Cxcl2 antibody at 2 h after APAP significantly reduced neutrophil accumulation at 24 h after both doses and in both sexes. However, the injury was significantly reduced only after the high overdose. Thus, neutrophils, recruited through Cxcl2, have no effect on APAP-induced liver injury after 300 mg/kg but aggravate the injury only after severe overdoses.

Study of emerging chicken meat quality defects using OMICs: What do we know?

Starting in approximately 2010, broiler breast meat myopathies, specifically woody breast meat, white striping, spaghetti meat, and gaping have increased in prevalence in the broiler meat industry. Omic methods have been used to elucidate compositional, genetic, and biochemical differences between myopathic and normal breast meat and have provided information on the factors that contribute to these myopathies. This review paper focuses on the genomic, transcriptomic, proteomic, metabolomic, and other omics research that has been conducted to unravel the molecular mechanisms involved in the development of these myopathies and their associated factors and potential causes. SIGNIFICANCE: This review manuscript summarizes poultry meat quality defects, also referred to as myopathies, that have been evaluated using omics methods. Genomics, transcriptomics, proteomics, metabolomics and other methodologies have been used to understand the genetic predisposition, the protein expression, and the biochemical pathways that are associated with the expression of woody breast meat, white striping, and other myopathies. This has allowed researchers and the industry to differentiate between chicken breast meat with and without myopathic muscle as well as the environmental and genetic conditions that contribute to differences in biochemical pathways and lead to the phenotypes associate with these different myopathies.

Decreased susceptibility of Plasmodium falciparum to both dihydroartemisinin and lumefantrine in northern Uganda.

Artemisinin partial resistance may facilitate selection of Plasmodium falciparum resistant to combination therapy partner drugs. We evaluated 99 P. falciparum isolates collected in 2021 from northern Uganda, where resistance-associated PfK13 C469Y and A675V mutations have emerged, and eastern Uganda, where these mutations are uncommon. With the ex vivo ring survival assay, isolates with the 469Y mutation (median survival 7.3% for mutant, 2.5% mixed, and 1.4% wild type) and/or mutations in Pfcoronin or falcipain-2a, had significantly greater survival; all isolates with survival >5% had mutations in at least one of these proteins. With ex vivo growth inhibition assays, susceptibility to lumefantrine (median IC50 14.6 vs. 6.9 nM, p < 0.0001) and dihydroartemisinin (2.3 vs. 1.5 nM, p = 0.003) was decreased in northern vs. eastern Uganda; 14/49 northern vs. 0/38 eastern isolates had lumefantrine IC50 > 20 nM (p = 0.0002). Targeted sequencing of 819 isolates from 2015-21 identified multiple polymorphisms associated with altered drug susceptibility, notably PfK13 469Y with decreased susceptibility to lumefantrine (p = 6 × 10-8) and PfCRT mutations with chloroquine resistance (p = 1 × 10-20). Our results raise concern regarding activity of artemether-lumefantrine, the first-line antimalarial in Uganda.

FFP maintains normal coagulation while Kcentra induces a hypercoagulable state in a porcine model of pulmonary contusion and hemorrhagic shock.

BACKGROUND: Moderate injury can lead to a coagulopathy. Fresh frozen plasma (FFP) corrects coagulopathy by means of a balanced array of clotting factors. We sought to compare the late effects of FFP and a prothrombin complex concentrate (PCC) on the coagulopathy of trauma using a porcine model of pulmonary contusion (PC) and hemorrhagic shock (HS) designed to evaluate the organ protective effects of these treatments. METHODS: Female Yorkshire swine (40-50 kg) were randomized to receive PC + HS or control (instrumented and uninjured). A blunt PC was created using a captive bolt gun. To induce HS, a liver crush injury was performed. Eighty minutes after injury, swine were treated with 25 U·kg-1 PCC, 1 U FFP, or 50 mL lactated Ringer's vehicle in a blinded manner. Arterial blood samples were drawn every 6 hours. Swine were euthanized 48 hours postinjury. Data were analyzed by Pearson χ2, analysis of variance and Kruskal-Wallis tests with Tukey's or Mann-Whitney U tests for post hoc analysis. RESULTS: Twenty-seven swine received PC + HS, 3 groups of 9 per group received PCC, FFP, or vehicle. Nine were noninjured controls. When compared with control, PC + HS swine had significantly shortened R time at 6 hours, 36 hours, and 42 hours, decreased LY30 at 12 hours, shortened K time at 30 hours and reduced α angle at 42 hours. PC + HS swine showed significant differences between treatment groups in K and α angle at 3 hours, LY30 at 12 hours and 18 hours, and MA at 12 hours, 18 hours, and 30 hours. Post hoc analysis was significant for higher α angle in PCC versus vehicle at 3 hours, higher MA in vehicle versus PCC at 12 hours and 18 hours, and higher LY30 in PCC versus vehicle at 18 hours (p < 0.012) with no significant differences between FFP and vehicle. CONCLUSION: Severe injury with HS induced a coagulopathy in swine. While FFP maintained normal coagulation following injury, PCC induced more rapid initial clot propagation in injured animals.

A prefrontal-bed nucleus of the stria terminalis circuit limits fear to uncertain threat.

In many cases of trauma, the same environmental stimuli that become associated with aversive events are experienced on other occasions without adverse consequence. We examined neural circuits underlying partially reinforced fear (PRF), whereby mice received tone-shock pairings on half of conditioning trials. Tone-elicited freezing was lower after PRF conditioning than fully reinforced fear (FRF) conditioning, despite an equivalent number of tone-shock pairings. PRF preferentially activated medial prefrontal cortex (mPFC) and bed nucleus of the stria terminalis (BNST). Chemogenetic inhibition of BNST-projecting mPFC neurons increased PRF, not FRF, freezing. Multiplexing chemogenetics with in vivo neuronal recordings showed elevated infralimbic cortex (IL) neuronal activity during CS onset and freezing cessation; these neural correlates were abolished by chemogenetic mPFC→BNST inhibition. These data suggest that mPFC→BNST neurons limit fear to threats with a history of partial association with an aversive stimulus, with potential implications for understanding the neural basis of trauma-related disorders.

While walking home alone late one night, you hear footsteps behind you. Your heart starts to beat faster as you wonder whether someone might be following you. Being able to identify and evade threats is essential for survival. A key part of this process is learning to recognize signals that predict potential danger: the sound of footsteps behind you, for example. But many such cues are unreliable. The person behind you might simply be heading in the same general direction as you. And if you spend too much time and energy responding to such false alarms, you may struggle to complete other essential tasks. To be useful, responses to cues that signal potential threats must thus be proportionate to the likelihood that danger is actually present. By studying threat detection in mice, Glover et al. have identified a brain circuit that helps ensure that this is the case. Two groups of mice learned to fear a tone that predicted the delivery of a mild footshock. In one group of animals, the tone was followed by a shock on every trial (it was said to be 'fully reinforced'). But in the other group, the tone was followed by a shock on only 50% of trials ('partially reinforced'). After training, both groups of mice froze whenever they heard the tone ­ freezing being a typical fear response in rodents. But the animals trained with the partially reinforced tone showed less freezing than their counterparts in the fully reinforced group. Moreover, freezing in response to the partially reinforced tone was accompanied by activity in a specific neural pathway connecting the frontal part of the brain to an area called the bed nucleus of the stria terminalis. Inhibiting this pathway made mice respond to the partially reinforced tone as though it had been reinforced on every trial. This suggests that activity in this pathway helps dampen responses to unpredictable threat cues. In people with anxiety disorders, cues that become associated with unpleasant events can trigger anxiety symptoms, even if the association is unreliable. The findings of Glover et al. suggest that reduced activity of circuits that constrain excessive responses to threats might contribute to anxiety disorders.

Liquid plasma reduces waste and health care expenses compared with thawed plasma at a Level I trauma center.

BACKGROUND: Balanced resuscitation strategies have led to increased utilization of plasma. Fresh frozen plasma that is thawed and never used is a large source of blood component wastage. Thawed plasma (TP) and can only be stored for 5 days. Liquid plasma (LP) has never been frozen and can be stored for 26 days. Due to longer storage duration, we hypothesized that using LP would result in decreased waste and cost savings compared with TP. METHODS: We performed a retrospective review of all trauma patients at our Level I trauma center in the years 2015 to 2016. We compared 2015 when only TP was used to 2016 when both TP and LP were used. All plasma units ordered for trauma patients were tracked until the time of transfusion or wastage. Wastage rates were compared between years and plasma type. RESULTS: There were 5,789 trauma patients admitted to our institution from 2015 to 2016. There were 4,107 plasma units ordered with 487 (11.9%) units wasted. During 2015, 2,021 total units of plasma were ordered with 273 (13.5%) units wasted which was a significantly higher rate than 2016 when 2,086 total units of plasma were ordered and 214 (10.3%) units were wasted (p = 0.0013). During 2016, 1,739 units of TP were ordered and 204 (11.7%) units were wasted which was significantly higher than LP wastage, 347 units ordered and 10 (2.9%) units wasted (p < 0.001). Of the 477 wasted TP units, 76.9% were ordered no more than two times before being wasted and 95.8% were ordered no more than three times before being wasted. Of the 10 LP units wasted, 40% were ordered no more than two times before being wasted, and 50% were ordered no more than three times before being wasted. If TP was wasted at the same rate as LP, 368 fewer units of plasma would have been wasted representing US $39,376 (US $107/unit) of wasted health care expenses. CONCLUSION: At a Level I trauma center, the addition of LP to the blood bank for trauma resuscitations significantly reduced plasma wastage rates and health care expenses. LEVEL OF EVIDENCE: Level III, Economic/Decision.

Use of bilobed partial resuscitative endovascular balloon occlusion of the aorta is logistically superior in prolonged management of a highly lethal aortic injury.

BACKGROUND: Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a viable technique for management of noncompressible torso hemorrhage. The major limitation of the current unilobed fully occlusive REBOA catheters is below-the-balloon ischemia-reperfusion complications. We hypothesized that partial aortic occlusion with a novel bilobed partial (p)REBOA-PRO would result in the need for less intraaortic balloon adjustments to maintain a distal goal perfusion pressure as compared with currently available unilobed ER-REBOA. METHODS: Anesthetized (40-50 kg) swine randomized to control (no intervention), ER-REBOA, or pREBOA-PRO underwent supraceliac aortic injury. The REBOA groups underwent catheter placement into zone 1 with initial balloon inflation to full occlusion for 10 minutes followed by gradual deflation to achieve and subsequently maintain half of the baseline below-the-balloon mean arterial pressure (MAP). Physiologic data and blood samples were collected at baseline and then hourly. At 4 hours, the animals were euthanized, total blood loss and urine output were recorded, and tissue samples were collected. RESULTS: Baseline physiologic data and basic laboratories were similar between groups. Compared with control, interventions similarly prolonged survival from a median of 18 minutes to over 240 minutes with comparable mortality trends. Blood loss was similar between partial ER-REBOA (41%) and pREBOA-PRO (51%). Partial pREBOA-PRO required a significantly lower number of intraaortic balloon adjustments (10 ER-REBOA vs. 3 pREBOA-PRO, p < 0.05) to maintain the target below-the-balloon MAP. The partial ER-REBOA group developed significantly increased hypercapnia, fibrin clot formation on TEG, liver inflammation, and IL-10 expression compared with pREBOA-PRO. CONCLUSION: In this highly lethal aortic injury model, use of bilobed pREBOA-PRO for a 4-hour partial aortic occlusion was logistically superior to unilobed ER-REBOA. It required less intraaortic balloon adjustments to maintain target MAP and resulted in less inflammation.

Aggressive treatment of acute kidney injury and hyperkalemia improves survival in a combat relevant trauma model in swine.

INTRODUCTION: Our swine model of pulmonary contusion (PC) and hemorrhagic shock (HS) was initially complicated by renal failure, hyperkalemia, and premature death. To study the effects of novel therapies on organ failure, improved survival was necessary requiring the design of an aggressive treatment regimen. METHODS: Anesthetized swine sustained either PC or PC with grade V liver injury to induce HS (PC + HS). After injury, animals were resuscitated followed by either standard care (SC) with maintenance intravenous fluids (IVF) and treatment at potassium level of 6.0 mmol/L (n = 7; 3 PC, 4 PC + HS) or aggressive care (AC) with increased initial IVF, early and frequent potassium monitoring, and treatment at potassium level of 5.0 mmol/L (n = 15, 8 PC, 7 PC + HS). Hyperkalemia was treated with calcium, insulin, and glucose in both groups. RESULTS: Survival to 48 h was achieved in 13/15 (87%) in the AC group and 2/7 (29%) in the SC group (p = 0.014). Compared to SC, AC improved median survival (48 vs. 18 h, p = 0.008) and lowered potassium (5.0 vs. 7.5 mmol/L), creatinine (2.4 vs. 4.0 mg/dL), BUN (27.5 vs. 39.0 mg/dL), and lactate (0.97 vs. 3.57 mmol/L) at the last observed time-point prior to death. For PC + HS animals, survival to 48 h was achieved in 6/7 in the AC group and 0/4 in the SC group with an improved median survival in the AC group (48 vs. 18 h, p = 0.011) DISCUSSION: Aggressive and early hyperkalemia treatment prolongs survival while reducing kidney injury and potassium levels in a combat relevant injury model in swine.

Female Collegiate Dancers Body Composition, Macronutrient and Micronutrient Intake Over Two Academic Years: A Longitudinal Analysis.

Collegiate dancers face unique challenges to maintain a lean aesthetic, optimal diet, and a high-performance level due to the various stressors in college. The purpose of this study was to examine changes in body composition (BC) and diet over two years. Participants (N = 17, 19.6 ± 1.6 years) completed two laboratory sessions per semester. Sessions included height and weight, BC, dietary intake, and a health history questionnaire. Regardless of rigorous dance training and variations in the academic calendar, no significant changes in BC or diet were observed within semesters of over two years. BMI was normal (24.9 ± 4.1 kg/m2) with fat mass exceeding 30% at all timepoints. Fat mass was negatively correlated with carbohydrate, fat, and protein intake (g/kg/day; r = -0.291, p = 0.004; r = -0.372, p < 0.0001; r = -0.398, p < 0.0001; respectively). Energy intake was within the recommended daily allowance (2040 ± 710 kcal/day), however may be insufficient for an active dance population. Protein (1.1 ± 0.5 g/kg), carbohydrate (3.7 ± 1.6 g/kg), calcium (835 ± 405 mg/day), iron (17 ± 15 mg/day), and potassium (1628 ± 1736 mg/day) intake fell below recommendations for an active population. Alterations in dance training and the demands of the academic calendar may be contributing to suboptimal dietary intake and BC in female collegiate dancers.

Bone marrow donor selection and characterization of MSCs is critical for pre-clinical and clinical cell dose production.

BACKGROUND: Cell based therapies, such as bone marrow derived mesenchymal stem cells (BM-MSCs; also known as mesenchymal stromal cells), are currently under investigation for a number of disease applications. The current challenge facing the field is maintaining the consistency and quality of cells especially for cell dose production for pre-clinical testing and clinical trials. Here we determine how BM-donor variability and thus the derived MSCs factor into selection of the optimal primary cell lineage for cell production and testing in a pre-clinical swine model of trauma induced acute respiratory distress syndrome. METHODS: We harvested bone marrow and generated three different primary BM-MSCs from Yorkshire swine. Cells from these three donors were characterized based on (a) phenotype (morphology, differentiation capacity and flow cytometry), (b) in vitro growth kinetics and metabolic activity, and (c) functional analysis based on inhibition of lung endothelial cell permeability. RESULTS: Cells from each swine donor exhibited varied morphology, growth rate, and doubling times. All expressed the same magnitude of standard MSC cell surface markers by flow cytometry and had similar differentiation potential. Metabolic activity and growth potential at each of the passages varied between the three primary cell cultures. More importantly, the functional potency of the MSCs on inhibition of endothelial permeability was also cell donor dependent. CONCLUSION: This study suggests that for production of MSCs for cell-based therapy, it is imperative to examine donor variability and characterize derived MSCs for marker expression, growth and differentiation characteristics and testing potency in application dependent assays prior to selection of the optimal cell lineage for large scale expansion and dose production.

Consumption of alcohol leads to platelet inhibition in men.

INTRODUCTION: Alcohol consumption has been shown to alter coagulation. However, thromboelastography with platelet mapping (TEG PM) to evaluate platelet function has not been studied. METHODS: A prospective, non-randomized study of healthy volunteers was conducted. Baseline TEG PM were collected. Subjects consumed alcoholic or non-alcoholic beverages for 2 h. Repeat TEG PM was collected. RESULTS: Fifty-four volunteers entered either the experimental group (EG, 17 women and 16 men) or control group (CG, 11 women and 10 men). After 2 h of alcohol or non-alcoholic drink consumption the median breath alcohol level was 0.08 [IQR 0.05, 0.12] in the EG and 0.00 in the CG. After consumption of alcohol, male EG subjects demonstrated higher median Adenosine Diphosphate (ADP) inhibition of platelet function (15.7% [3.9, 39.3] vs 8.2% [0, 30.1), p = 0.035), but female subjects did not. There was no evidence of increased arachidonic acid (AA) platelet inhibition in the EG compared to CG. Clot strength (TEG maximum amplitude) was not different between groups. CONCLUSION: After consumption of alcohol, healthy male volunteers demonstrate ADP platelet inhibition by TEG PM.

A scoring system to predict postoperative medical complications in high-risk patients undergoing elective thoracic and lumbar arthrodesis.

BACKGROUND CONTEXT: Various surgical factors affect the incidence of postoperative medical complications following elective spinal arthrodesis. Because of the inter-relatedness of these factors, it is difficult for clinicians to accurately risk-stratify individual patients. PURPOSE: Our goal was to develop a scoring system that predicts the rate of major medical complications in patients with significant preoperative medical comorbidities, as a function of the four perioperative parameters that are most closely associated with the invasiveness of the surgical intervention. STUDY DESIGN/SETTING: This study used level 2, Prognostic Retrospective Study. PATIENT SAMPLE: The patient sample consisted of 281 patients with American Society of Anesthesiologists (ASA) scores of 3-4 who underwent elective thoracic, lumbar, or thoracolumbar fusion surgeries from 2007 to 2011. OUTCOME MEASURES: Physiologic risk factors, number of levels fused, complications, operative time, intraoperative fluids, and estimate blood loss were the outcome measures of this study. METHODS: Risk factors were recorded, and patients who suffered major medical complications within the 30-day postoperative period were identified. We used chi-square tests to identify factors that affect the medical complication rate. These factors were ranked and scored by quartiles. The quartile scores were combined to form a single composite score. We determined the major medical complication rate for each composite score, and divided the cohort into quartiles again based on score. A Pearson linear regression analysis was used to compare the incidence of complications to the score. RESULTS: The number of fused levels, operative time, volume of intraoperative fluids, and estimated blood loss influenced the complication rate of patients with ASA scores of 3-4. The quartile ranking of each of the four predictive factors was added, and the sum became the composite score. This score predicted the complication rate in a linear fashion ranging from 7.6% for the lowest risk group to 34.7% for the highest group (r=0.998, p<.001). CONCLUSIONS: Taken together, the four factors, though not independent of one another, proved to be strongly predictive of the major medical complication rate. This score can be used to guide medical management of thoracic and lumbar spinal arthrodesis patients with preexisting medical comorbidities.

Are distal femoral traction pins intra-articular? A cadaveric study.

OBJECTIVES: To examine the frequency of intra-articular placement of distal femoral traction pins and their proximity to the superficial femoral artery (SFA). METHODS: Wires were placed in the distal femurs of 28 cadaveric knees at the adductor tubercle (ADT), the superior pole of the patella (SPP), and 2 cm proximal to SPP (SPP+2). A lateral fluoroscopic image was obtained after injection of radiopaque contrast to assess for joint penetration. Dissection was performed to confirm or refute fluoroscopic findings. The distance from each wire to the SFA was measured. RESULTS: The percentage of intra-articular placement was higher (29%) at the ADT than the SPP+2 (0%) level. The mean (SD) distances from the ADT, SPP, and SPP+2 to the SFA were 7.4 (±1.8) cm, 5.7 (±1.7) cm, and 3.8 (±1.7) cm, respectively (P < 0.0001). None of the wires penetrated the femoral artery. The proportion of wires judged to be intra-articular was not statistically different whether judged by fluoroscopy or anatomic dissection (exact P = 1.0). CONCLUSIONS: Wires placed at the level of the ADT are at risk for capsular penetration. Risk of major vascular injury with transmedullary placement at all levels seems to be minimal. The optimum position for distal femoral pins remains unknown, but aiming >0.7 cm proximal to the ADT may lower the risk of intra-articular placement. No difference was detected between fluoroscopic arthrography and gross dissection.