Cautionary tales on the use of proxies to estimate body size and form of extinct animals.

Body size is of fundamental importance to our understanding of extinct organisms. Physiology, ecology and life history are all strongly influenced by body size and shape, which ultimately determine how a species interacts with its environment. Reconstruction of body size and form in extinct animals provides insight into the dynamics underlying community composition and faunal turnover in past ecosystems and broad macroevolutionary trends. Many extinct animals are known only from incomplete remains, necessitating the use of anatomical proxies to reconstruct body size and form. Numerous limitations affecting the appropriateness of these proxies are often overlooked, leading to controversy and downstream inaccuracies in studies for which reconstructions represent key input data. In this perspective, we discuss four prominent case studies (Dunkleosteus, Helicoprion, Megalodon and Perucetus) in which proxy taxa have been used to estimate body size and shape from fragmentary remains. We synthesise the results of these and other studies to discuss nuances affecting the validity of taxon selection when reconstructing extinct organisms, as well as mitigation measures that can ensure the selection of the most appropriate proxy. We argue that these precautionary measures are necessary to maximise the robustness of reconstructions in extinct taxa for better evolutionary and ecological inferences.

Genomic and epigenomic analysis of plasma cell-free DNA identifies stemness features associated with worse survival in lethal prostate cancer.

PURPOSE: Metastatic castration-resistant prostate cancer (mCRPC) resistant to androgen receptor signaling inhibitors (ARSIs) is often lethal. Liquid biopsy biomarkers for this deadly form of disease remain under investigation, and underpinning mechanisms remain ill-understood. EXPERIMENTAL DESIGN: We applied targeted cell-free DNA sequencing to 126 mCRPC patients from three academic cancer centers, and separately performed genome-wide cell-free DNA methylation sequencing on 43 plasma samples collected prior to the initiation of first-line ARSI treatment. To analyze the genome-wide sequencing data, we performed nucleosome-positioning and differential methylated region analysis. We additionally analyzed single-cell and bulk RNA sequencing data from 14 and 80 mCRPC patients, respectively, to develop and validate a stem-like signature, which we inferred from cell-free DNA. RESULTS: Targeted cell-free DNA sequencing detected AR/enhancer alterations prior to first-line ARSIs which correlated with significantly worse PFS (p = 0.01; HR = 2.12) and OS (p = 0.02; HR = 2.48). Plasma methylome analysis revealed that AR/enhancer lethal mCRPC patients have significantly higher promoter-level hypomethylation than AR/enhancer wild-type mCRPC patients (p < 0.0001). Moreover, gene ontology and CytoTRACE analysis of nucleosomally more accessible transcription factors in cell-free DNA revealed enrichment for stemness-associated transcription factors in lethal mCRPC patients. The resulting stemness signature was then validated in a completely held-out cohort of 80 mCRPC patients profiled by tumor RNA sequencing. CONCLUSIONS: We analyzed a total of 220 mCRPC patients, validated the importance of cell-free AR/enhancer alterations as a prognostic biomarker in lethal mCRPC and showed that the underlying mechanism for lethality involves reprogramming developmental states toward increased stemness.

Differential neural mechanisms for movement adaptations following neuromuscular training in young female athletes with a history of sports-related concussion.

Sports-related concussion (SRC) in adolescent athletes is associated with an increased risk of subsequent lower extremity injury. Neuromuscular training (NMT) has shown promise for reducing lower extremity injuries following SRC, however, neural adaptations in response to changes in lower extremity biomechanics following NMT in athletes with a history of SRC (HxSRC) remains poorly understood. Therefore, the purpose of this study was to identify changes in neural activity associated with lower extremity movement adaptations following a six-week NMT intervention in athletes with a HxSRC. Thirty-two right-hand/foot-dominant female adolescent athletes (16 with self-reported HxSRC, 16 age- and anthropometrically-matched controls) completed a bilateral leg press task with 3D motion analysis during functional magnetic resonance imaging (fMRI). Movement adaptations were defined as a change in frontal and sagittal plane range of motion (ROM) during the fMRI bilateral leg press task. Significant pre- to post-NMT reductions were observed in the non-dominant (left) mean frontal plane ROM. Whole-brain neural correlate analysis revealed that increased cerebellar activity was significantly associated with reduced mean left-knee frontal ROM for matched controls. Exploratory within group analyses identified neural correlates in the postcentral gyrus for the HxSRC group which was associated with reduced mean left-knee frontal plane ROM. These distinct longitudinal changes provide preliminary evidence of differential neural activity associated with NMT to support knee frontal plane control in athletes with and without a HxSRC.

Timing of Kasai Procedure for Biliary Atresia: An Analysis of the Pediatric National Surgical Quality Improvement Program Database.

INTRODUCTION: Biliary atresia is a rare liver disease of unknown etiology affecting approximately 1 in 10,000 children. This disease initially presents as inflammatory obstruction of bile ducts leading to cholestasis and eventually fibrosis of hepatic tissue. Affected patients are ideally treated early with portoenterostomy (Kasai procedure) as age at surgery is an important prognostic factor for native liver survival and need for liver transplant. This study aimed to evaluate the age at which patients in the United States are receiving this procedure. METHODS: The American College of Surgeons National Surgical Quality Improvement Program Pediatric database was used to identify patients between 2012 and 2021 who underwent a primary procedure of portoenterostomy. The age at time of surgery and perioperative analysis was performed. The data underwent simple descriptive statistics. RESULTS: Eight hundred twenty four patients were identified who underwent Kasai procedure. Four hundred seventy four (58.2%) were female with the predominant race being White (49.5%). The median age at surgery was 57 d old (interquartile range 41-71). Readmission and reoperation rates within 30 d were 30% and 15.2%, respectively. There were no deaths within 30 d. CONCLUSIONS: Within the National Surgical Quality Improvement Program database, the median age of pediatric patients undergoing Kasai procedure for biliary atresia in the United States exceeds the goal of 45 d. Further studies are needed to investigate factors that may affect time to diagnosis and time to Kasai procedure.

Risk factors for prolonged infection and secondary infection in pediatric severe sepsis.

PURPOSE: Sepsis causes significant worldwide morbidity and mortality. Inability to clear an infection and secondary infections are known complications in severe sepsis and likely result in worsened outcomes. We sought to characterize risk factors of these complications. METHODS: We performed a secondary analysis of clinical data from 401 subjects enrolled in the PHENOtyping sepsis-induced Multiple organ failure Study. We examined factors associated with prolonged infection, defined as infection that continued to be identified 7 days or more from initial identification, and secondary infection, defined as new infections identified ≥ 3 days from presentation. Multivariable adjustment was performed to examine laboratory markers of immune depression, with immunocompromised and immunocompetent subjects analyzed separately. RESULTS: Illness severity, immunocompromised status, invasive procedures, and site of infection were associated with secondary infection and/or prolonged infection. Persistent lymphopenia, defined as an absolute lymphocyte count (ALC) < 1000 cells/µL twice in the first five days, and persistent neutropenia, defined as absolute neutrophil count (ANC) < 1000 cells/µL twice in the first five days, were associated with secondary and prolonged infections. When adjusted in multivariable analysis, persistent lymphopenia remained associated with secondary infection in both immunocompromised (aOR = 14.19, 95% CI [2.69, 262.22] and immunocompetent subjects (aOR = 2.09, 95% CI [1.03, 4.17]). Persistent neutropenia was independently associated with secondary infection in immunocompromised subjects (aOR = 5.34, 95% CI [1.92, 15.84]). Secondary and prolonged infections were associated with worse outcomes, including death. CONCLUSIONS: Laboratory markers of immune suppression can be used to predict secondary infection. Lymphopenia is an independent risk factor in immunocompromised and immunocompetent patients for secondary infection.

Apparent local anesthetic systemic toxicity following activation of an epidural catheter for cesarean delivery: diagnosis and management of an uncommon obstetric anesthesia complication.

We present a 25-year-old, gravida 2, para 1 woman who developed apparent local anesthetic systemic toxicity (LAST) following activation of an epidural catheter for an urgent cesarean delivery. The patient had a height of 150 cm, weight of 92 kg, body mass index of 41 kg/m2, and calculated ideal body weight of 40 kg. A combined spinal epidural anesthetic was placed and the spinal component did not provide anesthesia to clamping of the abdomen. Subsequently, 300 mg of lidocaine was administered through the epidural catheter in three 5 mL doses over 8 minutes and surgery commenced. Approximately 30 minutes following the final 5 mL dose of epidural lidocaine, the patient had progressive loss of consciousness and was difficult to arouse. A presumptive diagnosis of LAST was made, and 60 mL of 20% intravenous lipid emulsion was administered. The patient's mental status improved to baseline within 5 minutes of lipid emulsion administration, and she made a complete recovery. Anesthesiologists should consider using ideal body weight when calculating the maximum dosage of local anesthetics, and LAST should be part of the differential diagnosis when patients have altered mental status in the setting of local anesthetic administration that exceeds recommended dosages.

Fear of cancer recurrence experienced by pediatric survivors of childhood cancer: a scoping review.

PURPOSE: In contrast to the extensive literature on fear of cancer recurrence (FCR) experienced by adults, literature evaluating pediatric FCR has just begun to emerge. Given the rapidly expanding body of work assessing FCR in childhood and adolescence, a scoping review was conducted to synthesize existing findings. We aimed to assess (1) the characteristics and methods of this literature, (2) how pediatric FCR has been measured, and (3) the extant knowledge of FCR experienced by pediatric survivors of cancer. METHODS: Inclusion criteria were: (1) original reports, (2) participants diagnosed with cancer before age 18, (3) current mean age under 18, (4) FCR was explicitly measured (quantitatively) or captured (qualitatively) via survivor self-report, and (6) published in English. Exclusion criteria were: (1) case studies, and (2) grey literature. Three databases (Embase, MEDLINE, PsycINFO) and reference lists from included studies were searched. All studies were screened for inclusion by two authors and all data were extracted by a single author. RESULTS: Of 3906 identified studies, 19 were included. Studies (published 1991 - 2023) encompassed diverse geographical locations, study designs, and measurement methods. Few assessed FCR as a primary aim (n = 6, 32%). FCR was experienced by 43 - 90% of pediatric survivors. FCR was often positively associated with somatic symptoms and negatively associated with quality of life and emotional functioning. CONCLUSION: FCR is a prevalent issue for children and adolescents. Additional evidence is needed to explore and confirm preliminary findings. Future pediatric FCR studies should aim to align with published priority research areas.

Evaluating the Desirability of Outcome Ranking (DOOR) and Response Adjusted for Duration of Antibiotic Risk (RADAR) for Clinical Trials of Antibiotics in Pediatric Pneumonia.

Objective outcomes for pediatric community-acquired pneumonia (CAP) are lacking. The desirability of outcome ranking (DOOR) and response adjusted for duration of antibiotic risk (RADAR) outcome encompass clinical benefit and adverse effects, while also accounting for antibiotic exposure. We evaluated DOOR/RADAR through simulations and compared sample size considerations to non-inferiority designs in a hypothetical trial comparing antibiotics to no antibiotics (i.e., placebo) for children with mild CAP. We also evaluated a trial comparing different durations of antibiotics. Three scenarios were considered - one with no difference in DOOR between the two groups, one in which placebo is more efficacious, and another in which amoxicillin is more efficacious than placebo. Power to detect a difference between arms was greater using DOOR/RADAR compared to DOOR. Assuming a sample size of 200, DOOR had 2.5%, 50%, and 65% power to detect a statistical difference between arms for Scenarios 1-3, respectively, significantly less than DOOR/RADAR. Importantly, DOOR/RADAR incorrectly identified placebo as superior in Scenario 3 where amoxicillin was truly efficacious. Sample size requirements for non-inferiority designs were larger to achieve similar levels of power as DOOR and DOOR/RADAR. DOOR/RADAR has the potential to lead to an incorrect conclusion declaring placebo superior when amoxicillin is efficacious.

Transient Stress Lymphocytosis in a Child: A Case Report and Systematic Review of the Literature.

Transient stress lymphocytosis (TSL) is an under-recognized phenomenon associated with an acute stressful event such as physical trauma or various emergency medical conditions. Lymphocytosis generally resolves within several hours to days of the stressor. While most reports of TSL predominantly involve adult patients, it has only rarely been reported in pediatric patients. Here, we describe the clinical course of a 9-year-old male who developed TSL following a traumatic fall from a second-story balcony and provide a systematic literature review of TSL.

Social Determinants of Health and Health-Related Quality of Life Following Pediatric Septic Shock: Secondary Analysis of the Life After Pediatric Sepsis Evaluation Dataset, 2014-2017.

OBJECTIVES: Social determinants of health (SDOH) are associated with disparities in disease severity and in-hospital outcomes among critically ill children. It is unknown whether SDOH are associated with later outcomes. We evaluated associations between SDOH measures and mortality, new functional morbidity, and health-related quality of life (HRQL) decline among children surviving septic shock. DESIGN: Secondary analysis of the Life After Pediatric Sepsis Evaluation (LAPSE) prospective cohort study was conducted between 2014 and 2017. SETTING: Twelve academic U.S. PICUs were involved in the study. PATIENTS: Children younger than 18 years with community-acquired septic shock were involved in the study. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We assessed associations between race, ethnicity, income, education, marital status, insurance, language, and home U.S. postal code with day 28 mortality, new functional morbidity at discharge per day 28, and HRQL decline using logistic regression. Of 389 patients, 32% ( n = 98) of families had household income less than $50,000 per year. Median Pediatric Risk of Mortality (PRISM) score was 11 (interquartile range 6, 17). We found that English language and Area Deprivation Index less than 50th percentile were associated with higher PRISM scores. Mortality was 6.7% ( n = 26), new functional morbidity occurred in 21.8% ( n = 78) of patients, and HRQL decline by greater than 10% occurred in 31.0% of patients ( n = 63). We failed to identify any association between SDOH measures and mortality, new functional morbidity, or HRQL decline. We are unable to exclude the possibility that annual household income greater than or equal to $50,000 was associated with up to 81% lesser odds of mortality and, in survivors, more than three-fold greater odds of HRQL decline by greater than 10%. CONCLUSIONS: In this secondary analysis of the 2014-2017 LAPSE dataset, we failed to identify any association between SDOH measures and in-hospital or postdischarge outcomes following pediatric septic shock. This finding may be reflective of the high illness severity and single disease (sepsis) of the cohort, with contribution of clinical factors to functional and HRQL outcomes predominating over prehospital and posthospital SDOH factors.

Transient pores in hemifusion diaphragms.

Exchange of material across two membranes, as in the case of synaptic neurotransmitter release from a vesicle, involves the formation and poration of a hemifusion diaphragm (HD). The nontrivial geometry of the HD leads to environment-dependent control, regarding the stability and dynamics of the pores required for this kind of exocytosis. This work combines particle simulations, field-based calculations, and phenomenological modeling to explore the factors influencing the stability, dynamics, and possible control mechanisms of pores in HDs. We find that pores preferentially form at the HD rim, and that their stability is sensitive to a number of factors, including the three line tensions, membrane tension, HD size, and the ability of lipids to "flip-flop" across leaflets. Along with a detailed analysis of these factors, we discuss ways that vesicles or cells may use them to open and close pores and thereby quickly and efficiently transport material.

Correlation between locally versus centrally processed serum procalcitonin during emergency department research evaluation of febrile infants aged 0-60 days.

Introduction: Procalcitonin (PCT) is a useful biomarker in the initial evaluation of febrile infants for serious bacterial infections (SBIs). However, PCT is not always available locally and must at times be frozen and shipped to a reference laboratory for research studies. We sought to compare PCT measured locally versus centrally at a reference laboratory during a research study. Materials and methods: This was a secondary analysis of a multicenter study of febrile infants ≤60 days evaluated for SBIs from June 2016 to April 2019. A PCT cutoff value of 0.5 ng/mL was used to stratify infants at low-versus high-risk of SBIs. Statistical analyses consisted of Spearman's correlation, Bland-Altman difference plotting, Passing-Bablok regression, Deming regression, and Fisher's exact testing at the 0.5 ng/mL threshold. Results: 241 febrile infants had PCT levels measured both locally and at the reference laboratory. PCT levels measured locally on 5 different platforms and from the frozen research samples demonstrated strong Spearman's correlation (ρ = 0.83) and had similar mean PCT values with an average relative difference of 0.02%. Eleven infants with SBIs had PCT values < 0.5 ng/mL in both the clinical and research samples. Six other infants had differences in SBI prediction based on PCT values at the 0.5 ng/mL threshold between the clinical and research platforms. Conclusions: We found no significant differences in detection of febrile infants at high risk for SBI based on locally (on multiple platforms) versus centrally processed PCT. Testing at a central reference laboratory after freezing and shipping is an accurate and reliable alternative for research studies or when rapid turnaround is not required.

Understanding perceived park access and physical activity among older adults: A structural equation modeling approach.

Parks can provide a low-cost setting for safe physical activity, but older adults are underrepresented among park users in the United States. Using data from a population-representative survey in 2015 and 2018 among adults aged 60 years and older living in Philadelphia, we tested whether perceived access was a mechanism by which objectively-measured park access predicted self-reported physical activity. After controlling for individual-level factors and neighborhood characteristics, we found a statistically significant pathway from overall park area and within-park tree canopy to increased physical activity, mediated by perceived park access. These results highlight the importance of tree canopy for older adult park access and physical activity.

Evaluating Immune Checkpoint Blockade in Metastatic Castration-Resistant Prostate Cancers with Deleterious CDK12 Alterations in the Phase 2 IMPACT Trial.

PURPOSE: CDK12 inactivation in metastatic castration-resistant prostate cancer (mCRPC) may predict immunotherapy responses. This phase 2 trial evaluated the efficacy of immune checkpoint inhibitor (ICI) therapy in patients with CDK12-altered mCRPC. PATIENTS AND METHODS: Eligible patients had mCRPC with deleterious CDK12 alterations and any prior therapies except ICI. Cohort A received ipilimumab (1 mg/kg) with nivolumab (3 mg/kg) every 3 weeks for up to four cycles, followed by nivolumab 480 mg every 4 weeks. Cohort C received nivolumab alone 480 mg every 4 weeks. Patients with CDK12-altered nonprostate tumors were enrolled in cohort B and not reported. The primary endpoint was a 50% reduction in PSA (PSA50). Key secondary endpoints included PSA progression-free survival, overall survival, objective response rate, and safety. RESULTS: PSA was evaluable in 23 patients in cohort A and 14 in cohort C. Median lines of prior therapy were two in cohorts A and C, including any prior novel hormonal agent (74% and 79%) and chemotherapy (57% and 36%). The PSA50 rate was 9% [95% confidence interval (CI), 1%-28%] in cohort A with two responders; neither had microsatellite instability or a tumor mutational burden >10 mutations/megabase. No PSA50 responses occurred in cohort C. Median PSA progression-free survival was 7.0 months (95% CI, 3.6-11.4) in cohort A and 4.5 months (95% CI, 3.4-13.8) in cohort C. Median overall survival was 9.0 months (95% CI, 6.2-12.3) in cohort A and 13.8 months (95% CI, 3.6-not reached) in cohort C. CONCLUSIONS: There was minimal activity with ICI therapy in patients with CDK12-altered mCRPC.

End-of-Life Symptom Burden among Patients with Cancer Who Were Provided Medical Assistance in Dying (MAID): A Longitudinal Propensity-Score-Matched Cohort Study.

Cancer is the primary underlying condition for most Canadians who are provided Medical Assistance in Dying (MAID). However, it is unknown whether cancer patients who are provided MAID experience disproportionally higher symptom burden compared to those who are not provided MAID. Thus, we used a propensity-score-matched cohort design to evaluate longitudinal symptom trajectories over the last 12 months of patients' lives, comparing cancer patients in Alberta who were and were not provided MAID. We utilized routinely collected retrospective Patient-Reported Outcomes (PROs) data from the Edmonton Symptom Assessment System (ESAS-r) reported by Albertans with cancer who died between July 2017 and January 2019. The data were analyzed using mixed-effect models for repeated measures to compare differences in symptom trajectories between the cohorts over time. Both cohorts experienced increasing severity in all symptoms in the year prior to death (ß from 0.086 to 0.231, p ≤ .001 to .002). Those in the MAID cohort reported significantly greater anxiety (ß = -0.831, p = .044) and greater lack of appetite (ß = -0.934, p = .039) compared to those in the non-MAID cohort. The majority (65.8%) of patients who received MAID submitted their request for MAID within one month of their death. Overall, the MAID patients did not experience disproportionally higher symptom burden. These results emphasize opportunities to address patient suffering for all patients with cancer through routine collection of PROs as well as targeted and early palliative approaches to care.

Leukopenia, neutropenia, and procalcitonin levels in young febrile infants with invasive bacterial infections.

BACKGROUND AND OBJECTIVE: Serum procalcitonin (PCT) is a highly accurate biomarker for stratifying the risk of invasive bacterial infections (IBIs) in febrile infants ≤60 days old. However, PCT is unavailable in some settings. We explored the association of leukopenia and neutropenia with IBIs in non-critically ill febrile infants ≤60 days old, with and without PCT. METHODS: We conducted a secondary analysis of a prospective observational cohort consisting of 7407 non-critically ill infants ≤60 days old with temperatures ≥38°C. We focused on the risk of IBIs in patients with leukopenia (white blood cell [WBC] count <5000 cells/µL) or neutropenia (absolute neutrophil count [ANC] <1000 cells/µL), categorized to extremes of lower values, and the impact of PCT on these associations. Multiple logistic regression was used to identify independent predictors of IBIs. RESULTS: Final analysis included 6865 infants with complete data; 45% (3098) had PCT data available. Of the 6865, a total of 111 (1.6%) had bacteremia without bacterial meningitis, 18 (0.3%) had bacterial meningitis without bacteremia, and 19 (0.3%) had both bacteremia and bacterial meningitis. IBI was present in four of 20 (20%) infants with WBC counts ≤2500 cells/µL and four of 311 (1.3%) with ANC <1000 cells/µL. In multivariable logistic regression analysis not including PCT, a WBC count <2500 cells/µL was significantly associated with IBI (OR 13.48, 95% CI 2.92-45.35). However, no patients with leukopenia or neutropenia and PCT ≤0.5 ng/mL had IBIs. CONCLUSIONS: Leukopenia ≤2500 cells/µL in febrile infants ≤60 days old is associated with IBIs. However, in the presence of normal PCT levels, no patients with leukopenia had IBIs. While this suggests leukopenia ≤2500 cells/µL is a risk factor for IBIs in non-critically ill young febrile infants only when PCT is unavailable or elevated, the overall low frequency of leukopenia in this cohort warrants caution in interpretation, with future validation required.