Recent insights from non-mammalian models of brain injuries: an emerging literature

Traumatic brain injury (TBI) is a major global health concern and is increasingly recognized as a risk factor for neurodegenerative diseases including Alzheimer's disease (AD) and chronic traumatic encephalopathy (CTE). Repetitive TBIs (rTBIs), commonly observed in contact sports, military service, and intimate partner violence (IPV), pose a significant risk for long-term sequelae. To study the long-term consequences of TBI and rTBI, researchers have typically used mammalian models to recapitulate brain injury and neurodegenerative phenotypes. However, there are several limitations to these models, including: (1) lengthy observation periods, (2) high cost, (3) difficult genetic manipulations, and (4) ethical concerns regarding prolonged and repeated injury of a large number of mammals. Aquatic vertebrate model organisms, including Petromyzon marinus (sea lampreys), zebrafish (Danio rerio), and invertebrates, Caenorhabditis elegans (C. elegans), and Drosophila melanogaster (Drosophila), are emerging as valuable tools for investigating the mechanisms of rTBI and tauopathy. These non-mammalian models offer unique advantages, including genetic tractability, simpler nervous systems, cost-effectiveness, and quick discovery-based approaches and high-throughput screens for therapeutics, which facilitate the study of rTBI-induced neurodegeneration and tau-related pathology. Here, we explore the use of non-vertebrate and aquatic vertebrate models to study TBI and neurodegeneration. Drosophila, in particular, provides an opportunity to explore the longitudinal effects of mild rTBI and its impact on endogenous tau, thereby offering valuable insights into the complex interplay between rTBI, tauopathy, and neurodegeneration. These models provide a platform for mechanistic studies and therapeutic interventions, ultimately advancing our understanding of the long-term consequences associated with rTBI and potential avenues for intervention.

Healthcare Burden and Resource Utilization After Pediatric Acute Respiratory Distress Syndrome: A Secondary Analysis of the Collaborative Pediatric Critical Care Research Network Acute Respiratory Distress Syndrome Study

OBJECTIVES

To describe family healthcare burden and health resource utilization in pediatric survivors of acute respiratory distress syndrome (ARDS) at 3 and 9 months.

DESIGN

Secondary analysis of a prospective multisite cohort study.

SETTING

Eight academic PICUs in the United States (2019-2020).

PATIENTS

Critically ill children with ARDS and follow-up survey data collected at 3 and/or 9 months after the event.

INTERVENTIONS

None.

METHODS AND MEASUREMENT

We evaluated family healthcare burden, a measure of healthcare provided by families at home, and child health resource use including medication use and emergency department (ED) and hospital readmissions during the initial 3- and 9-month post-ARDS using proxy-report. Using multivariable logistic regression, we evaluated patient characteristics associated with family healthcare burden at 3 months.

MAIN RESULTS

Of 109 eligible patients, 74 (68%) and 63 patients (58%) had follow-up at 3- and 9-month post-ARDS. At 3 months, 46 families (62%) reported healthcare burden including (22%) with unmet care coordination needs. At 9 months, 33 families (52%) reported healthcare burden including 10 families (16%) with unmet care coordination needs. At month 3, 61 patients (82%) required prescription medications, 13 patients (18%) had ED visits and 16 patients (22%) required hospital readmission. At month 9, 41 patients (65%) required prescription medications, 19 patients (30%) had ED visits, and 16 (25%) required hospital readmission were reported. Medication use was associated with family healthcare burden at both 3 and 9 months. In a multivariable analysis, preillness functional status and chronic conditions were associated with healthcare burden at month 3 but illness characteristics were not.

CONCLUSIONS

Pediatric ARDS survivors report high rates of healthcare burden and health resource utilization at 3- and 9-month post-ARDS. Future studies should assess the impact of improved care coordination to simplify care (e.g., medication management) and improve family burden.

Viral Detection by Reverse Transcriptase Polymerase Chain Reaction in Upper Respiratory Tract and Metagenomic RNA Sequencing in Lower Respiratory Tract in Critically Ill Children With Suspected Lower Respiratory Tract Infection

OBJECTIVES

Viral lower respiratory tract infection (vLRTI) contributes to substantial morbidity and mortality in children. Diagnosis is typically confirmed by reverse transcriptase polymerase chain reaction (RT-PCR) of nasopharyngeal specimens in hospitalized patients; however, it is unknown whether nasopharyngeal detection accurately reflects presence of virus in the lower respiratory tract (LRT). This study evaluates agreement between viral detection from nasopharyngeal specimens by RT-PCR compared with metagenomic next-generation RNA sequencing (RNA-Seq) from tracheal aspirates (TAs).

DESIGN

This is an analysis of of a seven-center prospective cohort study.

SETTING

Seven PICUs within academic children's hospitals in the United States.

PATIENTS

Critically ill children (from 1 mo to 18 yr) who required mechanical ventilation via endotracheal tube for greater than or equal to 72 hours.

INTERVENTIONS

We evaluated agreement in viral detection between paired upper and LRT samples. Results of clinical nasopharyngeal RT-PCR were compared with TA RNA-Seq. Positive and negative predictive agreement and Cohen's Kappa were used to assess agreement.

MEASUREMENTS AND MAIN RESULTS

Of 295 subjects with paired testing available, 200 (68%) and 210 (71%) had positive viral testing by RT-PCR from nasopharyngeal and RNA-Seq from TA samples, respectively; 184 (62%) were positive by both nasopharyngeal RT-PCR and TA RNA-Seq for a virus, and 69 (23%) were negative by both methods. Nasopharyngeal RT-PCR detected the most abundant virus identified by RNA-Seq in 92.4% of subjects. Among the most frequent viruses detected, respiratory syncytial virus demonstrated the highest degree of concordance (κ = 0.89; 95% CI, 0.83-0.94), whereas rhinovirus/enterovirus demonstrated lower concordance (κ = 0.55; 95% CI, 0.44-0.66). Nasopharyngeal PCR was more likely to detect multiple viruses than TA RNA-Seq (54 [18.3%] vs 24 [8.1%], p ≤ 0.001).

CONCLUSIONS

Viral nucleic acid detection in the upper versus LRT reveals good overall agreement, but concordance depends on the virus. Further studies are indicated to determine the utility of LRT sampling or the use of RNA-Seq to determine LRTI etiology.

Sex-specific DNA methylation in saliva from the multi-ethnic Future of Families and Child Wellbeing Study

The prevalence and severity of many diseases differs by sex, potentially due to sex-specific patterns in DNA methylation. Autosomal sex-specific differences in DNA methylation have been observed in cord blood and placental tissue but are not well studied in saliva or in diverse populations. We sought to characterize sex-specific DNA methylation on autosomal chromosomes in saliva samples from children in the Future of Families and Child Wellbeing Study, a multi-ethnic prospective birth cohort containing an oversampling of Black, Hispanic and low-income families. DNA methylation from saliva samples was analysed on 796 children (50.6% male) at both ages 9 and 15 with DNA methylation measured using the Illumina HumanMethylation 450k array. An epigenome-wide association analysis of the age 9 samples identified 8,430 sex-differentiated autosomal DNA methylation sites (P < 2.4 × 10-7), of which 76.2% had higher DNA methylation in female children. The strongest sex-difference was in the cg26921482 probe, in the AMDHD2 gene, with 30.6% higher DNA methylation in female compared to male children (P < 1 × 10-300). Treating the age 15 samples as an internal replication set, we observed highly consistent results between the ages 9 and 15 measurements, indicating stable and replicable sex-differentiation. Further, we directly compared our results to previously published DNA methylation sex differences in both cord blood and saliva and again found strong consistency. Our findings support widespread and robust sex-differential DNA methylation across age, human tissues, and populations. These findings help inform our understanding of potential biological processes contributing to sex differences in human physiology and disease.

A novel metric to improve mismatched primer selection and quantification accuracy in amplifying DNA repeats for quantitative polymerase chain reactions

In quantitative polymerase chain reaction (qPCR) experiments, primers containing mismatches with respect to the template are widely used in measuring repetitive DNA elements. Primer-template mismatches may lead to underestimation of the input sample quantity due to inefficient annealing and amplification. But how primer-template mismatches affect quantification accuracy has not been rigorously investigated. In this study, we performed a series of qPCR experiments in which we tested three pairs of mismatched telomere primers (tel1/tel2, tel1b/tel2b and telg/telc) and two pairs of perfect-match reference gene primers (36B4-F/-R and IFNB1-F/-R) at three different primer concentrations under four cycling conditions. Templates used were genomic DNA from two human cell lines and oligo duplexes which contained telomere sequences, reference gene sequences, or both. We demonstrated that the underestimation of input sample quantity from reactions containing mismatched primers was not due to lower amplification efficiency (E), but due to ineffective usage of the input sample. We defined a novel concept of amplification efficacy (f) which quantifies the effectiveness of input sample amplification by primers. We have modified the conventional qPCR kinetic formula to include f, which corrects the effects of primer mismatches. We demonstrated that reactions containing mismatched telomere primer pairs had similar efficiency (E), but varying degrees of reduced efficacy (f) in comparison to those with the perfect-match gene primer pairs. Using the quantitative parameter f, underestimation of initial target by telomere primers can be adjusted to provide a more accurate measurement. Additionally, we found that the tel1b/tel2b primer set at concentration of 500 nM and 900 nM exhibited the best amplification efficacy f. This study provides a novel way to incorporate an evaluation of amplification efficacy into qPCR analysis. In turn, it improves mismatched primer selection and quantification accuracy in amplifying DNA repeats using qPCR methods.

Salivary Epigenetic Measures of Body Mass Index and Social Determinants of Health Across Childhood and Adolescence

Importance

Children who are socioeconomically disadvantaged are at increased risk for high body mass index (BMI) and multiple diseases in adulthood. The developmental origins of health and disease hypothesis proposes that early life conditions affect later-life health in a manner that is only partially modifiable by later-life experiences.

Objective

To examine whether epigenetic measures of BMI developed in adults are valid biomarkers of childhood BMI and if they are sensitive to early life social determinants of health.

Design, Setting, and Participants

This population-based study of over 3200 children and adolescents aged 8 to 18 years included data from 2 demographically diverse US pediatric cohort studies that combine longitudinal and twin study designs. Analyses were conducted from 2021 to 2022.

Exposures

Socioeconomic status, marginalized groups.

Main Outcome and Measure

Salivary epigenetic BMI, BMI. Analyses were conducted to validate the use of saliva epigenetic BMI as a potential biomarker of child BMI and to examine associations between epigenetic BMI and social determinants of health.

Results

Salivary epigenetic BMI was calculated from 2 cohorts: (1) 1183 individuals aged 8 to 18 years (609 female [51%]; mean age, 13.4 years) from the Texas Twin Project and (2) 2020 children (1011 female [50%]) measured at 9 years of age and 15 years of age from the Future of Families and Child Well-Being Study. Salivary epigenetic BMI was associated with children's BMI (r = 0.36; 95% CI, 0.31-0.40 to r = 0.50; 95% CI, 0.42-0.59). Longitudinal analysis found that epigenetic BMI was highly stable across adolescence but remained both a leading and lagging indicator of BMI change. Twin analyses showed that epigenetic BMI captured differences in BMI between monozygotic twins. Moreover, children from more disadvantaged socioeconomic status (b = -0.13 to -0.15 across samples) and marginalized racial and ethnic groups (b = 0.08-0.34 across samples) had higher epigenetic BMI, even when controlling for concurrent BMI, pubertal development, and tobacco exposure. Socioeconomic status at birth relative to concurrent socioeconomic status best predicted epigenetic BMI in childhood and adolescence (b = -0.15; 95% CI, -0.20 to -0.09).

Conclusion and Relevance

This study demonstrated that epigenetic measures of BMI calculated from pediatric saliva samples were valid biomarkers of childhood BMI and may be associated with early-life social inequalities. The findings are in line with the hypothesis that early-life conditions are especially important factors in epigenetic regulation of later-life health. Research showing that health later in life is linked to early-life conditions has important implications for the development of early-life interventions that could significantly extend healthy life span.

Acute Disorders of Consciousness in Pediatric Severe Sepsis and Organ Failure: Secondary Analysis of the Multicenter Phenotyping Sepsis-Induced Multiple Organ Failure Study

OBJECTIVES

Acute disorders of consciousness (DoC) in pediatric severe sepsis are associated with increased risk of morbidity and mortality. We sought to examine the frequency of and factors associated with DoC in children with sepsis-induced organ failure.

DESIGN

Secondary analysis of the multicenter Phenotyping Sepsis-Induced Multiple Organ Failure Study (PHENOMS).

SETTING

Nine tertiary care PICUs in the United States.

PATIENTS

Children less than 18 years old admitted to a PICU with severe sepsis and at least one organ failure during a PICU stay.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The primary outcome was frequency of DoC, defined as Glasgow Coma Scale (GCS) less than 12 in the absence of sedatives during an ICU stay, among children with severe sepsis and the following: single organ failure, nonphenotypeable multiple organ failure (MOF), MOF with one of the PHENOMS phenotypes (immunoparalysis-associated MOF [IPMOF], sequential liver failure-associated MOF, thrombocytopenia-associated MOF), or MOF with multiple phenotypes. A multivariable logistic regression analysis was performed to evaluate the association between clinical variables and organ failure groups with DoC. Of 401 children studied, 71 (18%) presented with DoC. Children presenting with DoC were older (median 8 vs 5 yr; p = 0.023), had increased hospital mortality (21% vs 10%; p = 0.011), and more frequently presented with both any MOF (93% vs 71%; p < 0.001) and macrophage activation syndrome (14% vs 4%; p = 0.004). Among children with any MOF, those presenting with DoC most frequently had nonphenotypeable MOF and IPMOF (52% and 34%, respectively). In the multivariable analysis, older age (odds ratio, 1.07; 95% CI, 1.01-1.12) and any MOF (3.22 [1.19-8.70]) were associated with DoC.

CONCLUSIONS

One of every five children with severe sepsis and organ failure experienced acute DoC during their PICU stay. Preliminary findings suggest the need for prospective evaluation of DoC in children with sepsis and MOF.

Association between the timing of childhood adversity and epigenetic patterns across childhood and adolescence: findings from the Avon Longitudinal Study of Parents and Children (ALSPAC) prospective cohort

BACKGROUND

Childhood adversity is a potent determinant of health across development and is associated with altered DNA methylation signatures, which might be more common in children exposed during sensitive periods in development. However, it remains unclear whether adversity has persistent epigenetic associations across childhood and adolescence. We aimed to examine the relationship between time-varying adversity (defined through sensitive period, accumulation of risk, and recency life course hypotheses) and genome-wide DNA methylation, measured three times from birth to adolescence, using data from a prospective, longitudinal cohort study.

METHODS

We first investigated the relationship between the timing of exposure to childhood adversity between birth and 11 years and blood DNA methylation at age 15 years in the Avon Longitudinal Study of Parents and Children (ALSPAC) prospective cohort study. Our analytic sample included ALSPAC participants with DNA methylation data and complete childhood adversity data between birth and 11 years. We analysed seven types of adversity (caregiver physical or emotional abuse, sexual or physical abuse [by anyone], maternal psychopathology, one-adult households, family instability, financial hardship, and neighbourhood disadvantage) reported by mothers five to eight times between birth and 11 years. We used the structured life course modelling approach (SLCMA) to identify time-varying associations between childhood adversity and adolescent DNA methylation. Top loci were identified using an R2 threshold of 0·035 (ie, ≥3·5% of DNA methylation variance explained by adversity). We attempted to replicate these associations using data from the Raine Study and Future of Families and Child Wellbeing Study (FFCWS). We also assessed the persistence of adversity-DNA methylation associations we previously identified from age 7 blood DNA methylation into adolescence and the influence of adversity on DNA methylation trajectories from ages 0-15 years.

FINDINGS

Of 13 988 children in the ALSPAC cohort, 609-665 children (311-337 [50-51%] boys and 298-332 [49-50%] girls) had complete data available for at least one of the seven childhood adversities and DNA methylation at 15 years. Exposure to adversity was associated with differences in DNA methylation at 15 years for 41 loci (R2 ≥0·035). Sensitive periods were the most often selected life course hypothesis by the SLCMA. 20 (49%) of 41 loci were associated with adversities occurring between age 3 and 5 years. Exposure to one-adult households was associated with differences in DNA methylation at 20 [49%] of 41 loci, exposure to financial hardship was associated with changes at nine (22%) loci, and physical or sexual abuse was associated with changes at four (10%) loci. We replicated the direction of associations for 18 (90%) of 20 loci associated with exposure to one-adult household using adolescent blood DNA methylation from the Raine Study and 18 (64%) of 28 loci using saliva DNA methylation from the FFCWS. The directions of effects for 11 one-adult household loci were replicated in both cohorts. Differences in DNA methylation at 15 years were not present at 7 years and differences identified at 7 years were no longer apparent by 15 years. We also identified six distinct DNA methylation trajectories from these patterns of stability and persistence.

INTERPRETATION

These findings highlight the time-varying effect of childhood adversity on DNA methylation profiles across development, which might link exposure to adversity to potential adverse health outcomes in children and adolescents. If replicated, these epigenetic signatures could ultimately serve as biological indicators or early warning signs of initiated disease processes, helping identify people at greater risk for the adverse health consequences of childhood adversity.

FUNDING

Canadian Institutes of Health Research, Cohort and Longitudinal Studies Enhancement Resources, EU's Horizon 2020, US National Institute of Mental Health.

Relative role of community transmission and campus contagion in driving the spread of SARS-CoV-2: Lessons from Princeton University

Mathematical models have played a crucial role in exploring and guiding pandemic responses. University campuses present a particularly well-documented case for institutional outbreaks, thereby providing a unique opportunity to understand detailed patterns of pathogen spread. Here, we present descriptive and modeling analyses of SARS-CoV-2 transmission on the Princeton University (PU) campus-this model was used throughout the pandemic to inform policy decisions and operational guidelines for the university campus. Epidemic patterns between the university campus and surrounding communities exhibit strong spatiotemporal correlations. Mathematical modeling analysis further suggests that the amount of on-campus transmission was likely limited during much of the wider pandemic until the end of 2021. Finally, we find that a superspreading event likely played a major role in driving the Omicron variant outbreak on the PU campus during the spring semester of the 2021-2022 academic year. Despite large numbers of cases on campus in this period, case levels in surrounding communities remained low, suggesting that there was little spillover transmission from campus to the local community.

Measuring the long arm of childhood in real-time: Epigenetic predictors of BMI and social determinants of health across childhood and adolescence

Children who are socioeconomically disadvantaged are at increased risk for high body mass index (BMI) and multiple diseases in adulthood. The developmental origins of health and disease hypothesis proposes that early life conditions affect later-life health in a manner that is only partially modifiable by later-life experiences. Epigenetic mechanisms may regulate the influence of early life conditions on later life health. Recent epigenetic studies of adult blood samples have identified DNA-methylation sites associated with higher BMI and worse health (epigenetic-BMI). Here, we used longitudinal and twin study designs to examine whether epigenetic predictors of BMI developed in adults are valid biomarkers of child BMI and are sensitive to early life social determinants of health. Salivary epigenetic-BMI was calculated from two samples: (1) N=1,183 8-to-19-year-olds (609 female, mean age=13.4) from the Texas Twin Project (TTP), and (2) N=2,020 children (1,011 female) measured at 9 and 15 years from the Future of Families and Child Well-Being Study (FFCWS). We found that salivary epigenetic-BMI is robustly associated with children's BMI (r=0.36 to r=0.50). Longitudinal analysis suggested that epigenetic-BMI is highly stable across adolescence, but remains both a leading and lagging indicator of BMI change. Twin analyses showed that epigenetic-BMI captures differences in BMI between monozygotic twins. Moreover, children from more disadvantaged socioeconomic status (SES) and marginalized race/ethnic groups had higher epigenetic-BMI, even when controlling for concurrent BMI, pubertal development, and tobacco exposure. SES at birth relative to concurrent SES best predicted epigenetic-BMI in childhood and adolescence. We show for the first time that epigenetic predictors of BMI calculated from pediatric saliva samples are valid biomarkers of childhood BMI that are sensitive to social inequalities. Our findings are in line with the hypothesis that early life conditions are especially important factors in epigenetic regulation of later life health. Research showing that health later in life is linked to early life conditions have important implications for the development of early-life interventions that could significantly extend healthy life span.

Mortality Risk in Pediatric Sepsis Based on C-reactive Protein and Ferritin Levels

OBJECTIVES

Interest in using bedside C-reactive protein (CRP) and ferritin levels to identify patients with hyperinflammatory sepsis who might benefit from anti-inflammatory therapies has piqued with the COVID-19 pandemic experience. Our first objective was to identify patterns in CRP and ferritin trajectory among critically ill pediatric sepsis patients. We then examined the association between these different groups of patients in their inflammatory cytokine responses, systemic inflammation, and mortality risks.

DATA SOURCES

A prospective, observational cohort study.

STUDY SELECTION

Children with sepsis and organ failure in nine pediatric intensive care units in the United States.

DATA EXTRACTION

Two hundred and fifty-five children were enrolled. Five distinct clinical multi-trajectory groups were identified. Plasma CRP (mg/dL), ferritin (ng/mL), and 31 cytokine levels were measured at two timepoints during sepsis (median Day 2 and Day 5). Group-based multi-trajectory models (GBMTM) identified groups of children with distinct patterns of CRP and ferritin.

DATA SYNTHESIS

Group 1 had normal CRP and ferritin levels ( n = 8; 0% mortality); Group 2 had high CRP levels that became normal, with normal ferritin levels throughout ( n = 80; 5% mortality); Group 3 had high ferritin levels alone ( n = 16; 6% mortality); Group 4 had very high CRP levels, and high ferritin levels ( n = 121; 11% mortality); and Group 5 had very high CRP and very high ferritin levels ( n = 30; 40% mortality). Cytokine responses differed across the five groups, with ferritin levels correlated with macrophage inflammatory protein 1α levels and CRP levels reflective of many cytokines.

CONCLUSIONS

Bedside CRP and ferritin levels can be used together to distinguish groups of children with sepsis who have different systemic inflammation cytokine responses and mortality risks. These data suggest future potential value in personalized clinical trials with specific targets for anti-inflammatory therapies.

Polymethylation scores for prenatal maternal smoke exposure persist until age 15 and are detected in saliva in the Fragile Families and Child Wellbeing cohort

Prenatal maternal smoking is associated with low birthweight, neurological disorders, and asthma in exposed children. DNA methylation signatures can function as biomarkers of prenatal smoke exposure. However, the robustness of DNA methylation signatures across child ages, genetic ancestry groups, or tissues is not clear. Using coefficients from a meta-analysis of prenatal smoke exposure and DNA methylation in newborn cord blood, we created polymethylation scores of saliva DNA methylation from children at ages 9 and 15 in the Fragile Families and Child Wellbeing study. In the full sample at age 9 (n = 753), prenatal smoke exposure was associated with a 0.51 (95%CI: 0.35, 0.66) standard deviation higher polymethylation score. The direction and magnitude of the association was consistent in European and African genetic ancestry samples. In the full sample at age 15 (n = 747), prenatal smoke exposure was associated with a 0.48 (95%CI: 0.32, 0.63) standard deviation higher polymethylation score, and the association was attenuated among the European and Admixed-Latin genetic ancestry samples. The polymethylation score classified prenatal smoke exposure accurately (AUC age 9 = 0.77, age 15 = 0.76). Including the polymethylation score increased the AUC of base model covariates by 5 (95% CI: (2.1, 7.2)) percentage points, while including a single candidate site in the AHRR gene did not (P-value = 0.19). Polymethylation scores for prenatal smoking were portable across genetic ancestries and more accurate than an individual DNA methylation site. Polymethylation scores from saliva samples could serve as robust and practical biomarkers of prenatal smoke exposure.

Assessment of Patient Health-Related Quality of Life and Functional Outcomes in Pediatric Acute Respiratory Distress Syndrome

OBJECTIVES

To describe health-related quality of life (HRQL) and functional outcomes in pediatric acute respiratory distress syndrome (ARDS) and to determine risk factors associated with poor outcome defined as death or severe reduction in HRQL at 28 days or ICU discharge.

DESIGN

Prospective multisite cohort-outcome study conducted between 2019 and 2020.

SETTING

Eight academic PICUs in the United States.

PATIENTS

Children with ARDS based on standard criteria.

INTERVENTIONS

Patient characteristics and illness severity were collected during PICU admission. Parent proxy-report measurements were obtained at baseline, day 28/ICU discharge, month 3, and month 9, utilizing Pediatric Quality of Life Inventory and Functional Status Scale (FSS). A composite outcome evaluated using univariate and multivariate analysis was death or severe reduction in HRQL (>25% reduction in the Pediatric Quality of Life Inventory at day 28/ICU discharge.

MEASUREMENTS AND MAIN RESULTS

This study enrolled 122 patients with a median age of 3 years (interquartile range, 1-12 yr). Common etiologies of ARDS included pneumonia ( n = 63; 52%) and sepsis ( n = 27; 22%). At day 28/ICU discharge, half (50/95; 53%) of surviving patients with follow-up data reported a greater than 10% decrease in HRQL from baseline, and approximately one-third of participants ( n = 19/61; 31%) reported a greater than 10% decrease in HRQL at 9 months. Trends in FSS were similar. Of 104 patients with data, 47 patients (45%) died or reported a severe decrease of greater than 25% in HRQL at day 28/ICU discharge. Older age was associated with an increased risk of death or severe reduction in HRQL (odds ratio, 1.08; CI, 1.01-1.16).

CONCLUSIONS

Children with ARDS are at risk for deterioration in HRQL and FSS that persists up to 9 months after ARDS. Almost half of children with ARDS experience a poor outcome including death or severe reduction in HRQL at day 28/ICU discharge.

PVP1-The People's Ventilator Project: A fully open, low-cost, pressure-controlled ventilator research platform compatible with adult and pediatric uses

Mechanical ventilators are safety-critical devices that help patients breathe, commonly found in hospital intensive care units (ICUs)-yet, the high costs and proprietary nature of commercial ventilators inhibit their use as an educational and research platform. We present a fully open ventilator device-The People's Ventilator: PVP1-with complete hardware and software documentation including detailed build instructions and a DIY cost of $1,700 USD. We validate PVP1 against both key performance criteria specified in the U.S. Food and Drug Administration's Emergency Use Authorization for Ventilators, and in a pediatric context against a state-of-the-art commercial ventilator. Notably, PVP1 performs well over a wide range of test conditions and performance stability is demonstrated for a minimum of 75,000 breath cycles over three days with an adult mechanical test lung. As an open project, PVP1 can enable future educational, academic, and clinical developments in the ventilator space.

Machine learning derivation of four computable 24-h pediatric sepsis phenotypes to facilitate enrollment in early personalized anti-inflammatory clinical trials

BACKGROUND

Thrombotic microangiopathy-induced thrombocytopenia-associated multiple organ failure and hyperinflammatory macrophage activation syndrome are important causes of late pediatric sepsis mortality that are often missed or have delayed diagnosis. The National Institutes of General Medical Science sepsis research working group recommendations call for application of new research approaches in extant clinical data sets to improve efficiency of early trials of new sepsis therapies. Our objective is to apply machine learning approaches to derive computable 24-h sepsis phenotypes to facilitate personalized enrollment in early anti-inflammatory trials targeting these conditions.

METHODS

We applied consensus, k-means clustering analysis to our extant PHENOtyping sepsis-induced Multiple organ failure Study (PHENOMS) dataset of 404 children. 24-hour computable phenotypes are derived using 25 available bedside variables including C-reactive protein and ferritin.

RESULTS

Four computable phenotypes (PedSep-A, B, C, and D) are derived. Compared to all other phenotypes, PedSep-A patients (n = 135; 2% mortality) were younger and previously healthy, with the lowest C-reactive protein and ferritin levels, the highest lymphocyte and platelet counts, highest heart rate, and lowest creatinine (p < 0.05); PedSep-B patients (n = 102; 12% mortality) were most likely to be intubated and had the lowest Glasgow Coma Scale Score (p < 0.05); PedSep-C patients (n = 110; mortality 10%) had the highest temperature and Glasgow Coma Scale Score, least pulmonary failure, and lowest lymphocyte counts (p < 0.05); and PedSep-D patients (n = 56, 34% mortality) had the highest creatinine and number of organ failures, including renal, hepatic, and hematologic organ failure, with the lowest platelet counts (p < 0.05). PedSep-D had the highest likelihood of developing thrombocytopenia-associated multiple organ failure (Adj OR 47.51 95% CI [18.83-136.83], p < 0.0001) and macrophage activation syndrome (Adj OR 38.63 95% CI [13.26-137.75], p < 0.0001).

CONCLUSIONS

Four computable phenotypes are derived, with PedSep-D being optimal for enrollment in early personalized anti-inflammatory trials targeting thrombocytopenia-associated multiple organ failure and macrophage activation syndrome in pediatric sepsis. A computer tool for identification of individual patient membership ( www.pedsepsis.pitt.edu ) is provided. Reproducibility will be assessed at completion of two ongoing pediatric sepsis studies.

Characterization of Inhaled Nitric Oxide Use for Cardiac Indications in Pediatric Patients

OBJECTIVES

Characterize the use of inhaled nitric oxide (iNO) for pediatric cardiac patients and assess the relationship between patient characteristics before iNO initiation and outcomes following cardiac surgery.

DESIGN

Observational cohort study.

SETTING

PICU and cardiac ICUs in seven Collaborative Pediatric Critical Care Research Network hospitals.

PATIENTS

Consecutive patients, less than 18 years old, mechanically ventilated before or within 24 hours of iNO initiation. iNO was started for a cardiac indication and excluded newborns with congenital diaphragmatic hernia, meconium aspiration syndrome, and persistent pulmonary hypertension, or when iNO started at an outside institution.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Four-hundred seven patients with iNO initiation based on cardiac dysfunction. Cardiac dysfunction patients were administered iNO for a median of 4 days (2-7 d). There was significant morbidity with 51 of 407 (13%) requiring extracorporeal membrane oxygenation and 27 of 407 (7%) requiring renal replacement therapy after iNO initiation, and a 28-day mortality of 46 of 407 (11%). Of the 366 (90%) survivors, 64 of 366 patients (17%) had new morbidity as assessed by Functional Status Scale. Among the postoperative cardiac surgical group (n = 301), 37 of 301 (12%) had a superior cavopulmonary connection and nine of 301 (3%) had a Fontan procedure. Based on echocardiographic variables prior to iNO (n = 160) in the postoperative surgical group, right ventricle dysfunction was associated with 28-day and hospital mortalities (both, p < 0.001) and ventilator-free days (p = 0.003); tricuspid valve regurgitation was only associated with ventilator-free days (p < 0.001), whereas pulmonary hypertension was not associated with mortality or ventilator-free days.

CONCLUSIONS

Pediatric patients in whom iNO was initiated for a cardiac indication had a high mortality rate and significant morbidity. Right ventricular dysfunction, but not the presence of pulmonary hypertension on echocardiogram, was associated with ventilator-free days and mortality.

Post-Traumatic Growth in Parents following Their Child's Death in a Pediatric Intensive Care Unit

Background: Although bereaved parents suffer greatly, some may experience positive change referred to as post-traumatic growth. Objective: Explore the extent to which parents perceive post-traumatic growth after their child's death in a pediatric intensive care unit (PICU), and associated factors. Design: Longitudinal parent survey conducted 6 and 13 months after a child's death. Surveys included the Post-traumatic Growth Inventory-Short Form (PTGI-SF), a 10-item measure with range of 0-50 where higher scores indicate more post-traumatic growth. Surveys also included the Inventory of Complicated Grief (ICG), the Patient Health Questionnaire-8 (PHQ-8) for depression, the Short Post-Traumatic Stress Disorder Rating Interview (SPRINT), a single item on perceived overall health, and sociodemographics. Setting/Subjects: One hundred fifty-seven parents of 104 children who died in 1 of 8 PICUs affiliated with the U.S. Collaborative Pediatric Critical Care Research Network. Results: Of participating parents, 62.4% were female, 71.6% White, 82.7% married, and 89.2% had at least a high school education. Mean PTGI-SF scores were 27.5 ± 12.52 (range 5-50) at 6 months and 28.6 ± 11.52 (range 2-49) at 13 months (p = 0.181). On multivariate modeling, higher education (compared with those not completing high school) and higher 6-month ICG scores (reflecting more complicated grief symptoms) were associated with lower 13-month PTGI-SF scores (p = 0.005 and 0.033, respectively). Conclusion: Parents bereaved by their child's PICU death perceive a moderate degree of post-traumatic growth in the first 13 months after the death however variability is wide. Education level and complicated grief symptoms may influence parents' perception of post-traumatic growth.

Prevalence of Pathogenic and Potentially Pathogenic Inborn Error of Immunity Associated Variants in Children with Severe Sepsis

Purpose

Our understanding of inborn errors of immunity is increasing; however, their contribution to pediatric sepsis is unknown.

Methods

We used whole-exome sequencing (WES) to characterize variants in genes related to monogenic immunologic disorders in 330 children admitted to intensive care for severe sepsis. We defined candidate variants as rare variants classified as pathogenic or potentially pathogenic in QIAGEN’s Human Gene Mutation Database or novel null variants in a disease-consistent inheritance pattern. We investigated variant correlation with infection and inflammatory phenotype.

Results

More than one in two children overall and three of four African American children had immunodeficiency-associated variants. Children with variants had increased odds of isolating a blood or urinary pathogen (blood: OR 2.82, 95% CI: 1.12–7.10, p = 0.023, urine: OR: 8.23, 95% CI: 1.06–64.11, p = 0.016) and demonstrating increased inflammation with hyperferritinemia (ferritin \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\ge 500$$\end{document}≥500 ng/mL, OR: 2.16, 95% CI: 1.28–3.66, p = 0.004), lymphopenia (lymphocyte count < 1000/µL, OR: 1.66, 95% CI: 1.06 – 2.60, p = 0.027), thrombocytopenia (platelet count < 150,000/µL, OR: 1.76, 95% CI: 1.12–2.76, p = 0.013), and CRP greater than 10 mg/dl (OR: 1.71, 95% CI: 1.10–2.68, p = 0.017). They also had increased odds of requiring extracorporeal membrane oxygenation (ECMO, OR: 4.19, 95% CI: 1.21–14.5, p = 0.019).

Conclusion

Herein, we describe the genetic findings in this severe pediatric sepsis cohort and their microbiologic and immunologic significance, providing evidence for the phenotypic effect of these variants and rationale for screening children with life-threatening infections for potential inborn errors of immunity.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10875-021-01183-4.

Inhaled Nitric Oxide Use and Outcomes in Critically Ill Children With a History of Prematurity

BACKGROUND

Inhaled nitric oxide (INO) is used to treat hypoxic respiratory failure without clear evidence of benefit. Future trials to evaluate its use will be designed based on an understanding of the populations in which this therapy is provided and with outcomes based on patient characteristics, for example, a history of premature birth.

METHODS

This was a multi-center prospective observational study that evaluated subjects in the pediatric ICU who were treated with INO for a respiratory indication, excluding those treated in the neonatal ICU or treated for birth-related disease. We used logistic regression to evaluate characteristics associated with mortality and duration of mechanical ventilation. Specifically, we compared subjects born early preterm (<32 weeks post-conceptual age), late preterm (32-37 weeks post-conceptual age), and full term.

RESULTS

A total of 163 children (median age [interquartile range], 1.8 [0.7-6.0] y) were included, 41 (25.2%) had a history of preterm birth (18 born early preterm and 23 born late preterm). INO was initiated for less-severe lung disease in the early preterm versus late preterm versus full-term subjects (median mean airway pressures, 16 vs 19 vs 19 cm H2O; P = .03), although the oxygenation index and oxygenation saturation index did not differ. The early preterm subjects had more ventilator-free days (median, 18.0, 7.0, 4.5 d; P = .02) and lower 28-d mortality (0, 26.1, 32.0%; P = .007). Lower respiratory tract disease, but not a history of prematurity, was independently associated with lower mortality.

CONCLUSIONS

INO was used differently in early preterm subjects. Clinical trials that evaluate INO use should have standardized oxygenation deficit thresholds for initiation of therapy and should consider stratifying by early preterm status.

Coming up short: Comparing venous blood, dried blood spots & saliva samples for measuring telomere length in health equity research

BACKGROUND

Telomere length (TL) in peripheral blood mononuclear cells (PBMC) from fresh venous blood is increasingly used to estimate molecular impacts of accumulated social adversity on population health. Sometimes, TL extracted from saliva or dried blood spots (DBS) are substituted as less invasive and more scalable specimen collection methods; yet, are they interchangeable with fresh blood? Studies find TL is correlated across tissues, but have not addressed the critical question for social epidemiological applications: Do different specimen types show the same association between TL and social constructs?

METHODS

We integrate expertise in social epidemiology, molecular biology, and the statistical impact of measurement error on parameter estimates. Recruiting a diverse sample of 132 Metro-Detroit women, we measure TL for each woman from fresh blood PBMC, DBS, and saliva. Using regression methods, we estimate associations between social characteristics and TL, comparing estimates across specimen types for each woman.

RESULTS

Associations between TL and social characteristics vary by specimen type collected from the same woman, sometimes qualitatively altering estimates of the magnitude or direction of a theorized relationship. Being Black is associated with shorter TL in PBMC, but longer TL in saliva or DBS. Education is positively associated with TL in fresh blood, but negatively associated with TL using DBS.

CONCLUSION

Findings raise concerns about the use of TL measures derived from different tissues in social epidemiological research. Investigators need to consider the possibility that associations between social variables and TL may be systematically related to specimen type, rather than be valid indicators of socially-patterned biopsychosocial processes.

Structured Chart Review: Assessment of a Structured Chart Review Methodology

BACKGROUND AND OBJECTIVES

Chart reviews are frequently used for research, care assessments, and quality improvement activities despite an absence of data on reliability and validity. We aim to describe a structured chart review methodology and to establish its validity and reliability.

METHODS

A generalizable structured chart review methodology was designed to evaluate causes of morbidity or mortality and to identify potential therapeutic advances. The review process consisted of a 2-tiered approach with a primary review completed by a site physician and a short secondary review completed by a central physician. A total of 327 randomly selected cases of known mortality or new morbidities were reviewed. Validity was assessed by using postreview surveys with a Likert scale. Reliability was assessed by percent agreement and interrater reliability.

RESULTS

The primary reviewers agreed or strongly agreed in 94.9% of reviews that the information to form a conclusion about pathophysiological processes and therapeutic advances could be adequately found. They agreed or strongly agreed in 93.2% of the reviews that conclusions were easy to make, and confidence in the process was 94.2%. Secondary reviewers made modifications to 36.6% of cases. Duplicate reviews (n = 41) revealed excellent percent agreement for the causes (80.5%-100%) and therapeutic advances (68.3%-100%). κ statistics were strong for the pathophysiological categories but weaker for the therapeutic categories.

CONCLUSIONS

A structured chart review by knowledgeable primary reviewers, followed by a brief secondary review, can be valid and reliable.

The Association between Therapeutic Alliance and Parental Health Outcomes following a Child's Death in the Pediatric Intensive Care Unit

Therapeutic alliance reflects the strength and quality of the physician-patient/family relationship. We investigated the association between therapeutic alliance and bereaved parents' mental health and perceived overall health following their child's death in a pediatric intensive care unit (PICU). Bereaved parents were surveyed 6 months after their child's death in a PICU affiliated with the Collaborative Pediatric Critical Care Research Network. Parents were evaluated for complicated grief, depression, and post-traumatic stress using the Inventory of Complicated Grief (ICG), the Patient Health Questionnaire (PHQ-8), and the Short Post-Traumatic Stress Disorder Rating Interview (SPRINT), respectively. Overall health was evaluated using a single item. Therapeutic alliance between parents and their deceased child's PICU physicians was assessed using the Human Connection scale (HCS). Two hundred and thirty-five parents of 158 deceased children completed surveys. Mean ICG score was 34.4 ± 14.9 with 142 (60.4%) parents screening positive for complicated grief. Mean PHQ-8 score was 9.1 ± 6.2 with 102 (43.4%) screening positive for at least moderate depression. Mean SPRINT score was 14.6 ± 8.2 with 122 (51.9%) screening positive for post-traumatic stress disorder. Overall health was perceived as fair for 47 (20.0%) parents and poor for 10 (4.3%). Using multivariable modeling, higher HCS score (greater therapeutic alliance) was significantly associated with lower (better) ICG score (-0.23, 95% CI -0.42, -0.04, p  = 0.018). HCS score was not significantly associated with PHQ-8, SPRINT, or overall health scores. We conclude that bereaved parents experience a high level of adverse mental health symptoms including complicated grief, depression, and post-traumatic stress symptoms. Greater therapeutic alliance with PICU physicians may lessen symptoms of complicated grief during bereavement.

Complicated Grief, Depression and Post-Traumatic Stress Symptoms Among Bereaved Parents following their Child's Death in the Pediatric Intensive Care Unit: A Follow-Up Study

BACKGROUND

Parents often suffer reduced mental health after their child's death; however, the trajectory and risk factors are not well described.

OBJECTIVE

Describe the change in complicated grief, depression, and post-traumatic stress symptoms among parents between 6 and 13 months after their child's death in a pediatric intensive care unit (PICU), and factors associated with 13-month symptoms.

METHODS

Parents whose children died in 1 of 8 PICUs affiliated with the Collaborative Pediatric Critical Care Research Network completed surveys 6 and 13 months after their child's death. Surveys included the Inventory of Complicated Grief (ICG), the Patient Health Questionnaire-8 (PHQ-8) for depression, and the Short Post-Traumatic Stress Disorder Rating Interview (SPRINT). Parents provided sociodemographics. Charts were reviewed for child characteristics.

RESULTS

One-hundred and fifty seven parents of 104 deceased children completed surveys at both time points. Mental health symptoms declined over time (mean (SD)): ICG (33.8 (15.4) vs. 30.5 (15.2), p < 0.001), PHQ-8 (9.0 (6.4) vs. 7.3 (5.8), p < 0.001), and SPRINT (14.1 (8.3) vs. 12.0 (8.2), p < 0.001). After controlling for 6-month scores, higher 13-month ICG was independently associated with sudden unexpected death; higher PHQ-8 with Black race, insecure attachment style, and sudden unexpected death; and higher SPRINT with having a high school level of education (compared to college degree or higher).

CONCLUSION

Mental health symptoms improve among parents during the first 13 months after their child's death; however, symptoms persist for many. Black parents and those whose children die suddenly may be high risk for poor adjustment during bereavement.

Therapeutic Alliance Between Bereaved Parents and Physicians in the PICU

OBJECTIVES

Therapeutic alliance is the collaborative bond that develops between patients/families and healthcare providers. Our objective is to determine the extent of therapeutic alliance bereaved parents perceive to have occurred with their child's physicians during their child's PICU stay, and associated factors.

DESIGN

Multicenter observational study.

SETTING

Eight children's hospitals affiliated with the Collaborative Pediatric Critical Care Research Network.

PATIENTS

Parents greater than or equal to 18 years old whose child died in a PICU (including cardiac ICU).

INTERVENTIONS

Bereaved parents completed the Human Connection Scale, a 16-item measure of therapeutic alliance, 6 months after their child's death. Human Connection Scale scores range from 16 to 64 with higher scores indicating greater alliance. Parents provided sociodemographic data, and medical records were reviewed for the child's clinical characteristics.

MEASUREMENTS AND MAIN RESULTS

Two-hundred and thirty-three parents of 157 deceased children responded to the Human Connection Scale with greater than or equal to 80% item completion. Among parents, 146 (62.7%) were female, 155 (66.5%) were White and 46 (19.7%) were Black, 175 (75.1%) were married, and 209 (89.7%) had at least a high-school education. Among children, median age at the time of death was 5.9 years (interquartile range, 0.64-13.9 yr) and 114 (72.6%) died after limitation or withdrawal of life support. Mean Human Connection Scale score was 51.4 ± 11.1 for all parents, 52.6 ± 9.0 for White parents, and 47.0 ± 13.7 for Black parents. In multivariable modeling predicting Human Connection Scale scores, race was the only parent or child characteristic in the final model. Human Connection Scale scores were significantly different (-4.56; 95% CI, -8.53 to -0.6; p = 0.025) between the Black and White parents with items about trust, care, and honest communication showing the greatest mean difference.

CONCLUSIONS

Among parents bereaved in the PICU, therapeutic alliance with physicians is moderately high. Future research should identify strategies to strengthen therapeutic alliance with Black parents and examine the role of alliance on bereaved parents' health outcomes.

Temporal airway microbiome changes related to ventilator-associated pneumonia in children

We sought to determine whether temporal changes in the lower airway microbiome are associated with ventilator-associated pneumonia (VAP) in children.Using a multicentre prospective study of children aged 31 days to 18 years requiring mechanical ventilation support for >72 h, daily tracheal aspirates were collected and analysed by sequencing of the 16S rRNA gene. VAP was assessed using 2008 Centers for Disease Control and Prevention paediatric criteria. The association between microbial factors and VAP was evaluated using joint longitudinal time-to-event modelling, matched case-control comparisons and unsupervised clustering.Out of 366 eligible subjects, 66 (15%) developed VAP at a median of 5 (interquartile range 3-5) days post intubation. At intubation, there was no difference in total bacterial load (TBL), but Shannon diversity and the relative abundance of Streptococcus, Lactobacillales and Prevotella were lower for VAP subjects versus non-VAP subjects. However, higher TBL on each sequential day was associated with a lower hazard (hazard ratio 0.39, 95% CI 0.23-0.64) for developing VAP, but sequential values of diversity were not associated with VAP. Similar findings were observed from the matched analysis and unsupervised clustering. The most common dominant VAP pathogens included Prevotella species (19%), Pseudomonas aeruginosa (14%) and Streptococcus mitis/pneumoniae (10%). Mycoplasma and Ureaplasma were also identified as dominant organisms in several subjects.In mechanically ventilated children, changes over time in microbial factors were marginally associated with VAP risk, although these changes were not suitable for predicting VAP in individual patients. These findings suggest that focusing exclusively on pathogen burden may not adequately inform VAP diagnosis.

Early childhood psychosocial family risks and cumulative dopaminergic sensitizing score: Links to behavior problems in U.S. 9-year-olds

BACKGROUND

We examined, (a) whether in early childhood exposure to risky family environment in different domains (socioeconomic, mental, parenting practices, health behavior, and child-related risks) and accumulatively across various domains (cumulative risk) is associated with child's problem behavior at age 9, and (b) whether the association is more pronounced in children carrying cumulative dopaminergic sensitizing genotype or living in low-income families.

METHODS

Participants were 2,860 9-year old children (48% females; 48% Black) and their mothers from the 'Fragile Families and Child Wellbeing Study', a probability birth cohort from large U.S. cities. Mothers responded to questions on child's problem behavior (CBCL). Children responded to questions about their vandalism and substance use.

RESULTS

Cumulative family risk was associated with higher internalizing and externalizing behavior and higher vandalism and substance use. All domain-specific risk clusters were associated with higher internalizing behavior and, with the exception of child-related risk, with higher externalizing behavior. Mental health risks, risky parenting practices, and risky health behavior were associated with higher vandalism. Risky parenting practices were associated with higher substance use. The associations were robust to adjustment for cumulative dopaminergic sensitizing genotype. No G x E interactions with dopaminergic genotype and family SES were observed.

LIMITATIONS

Sample size was relatively small for genetic analysis and polygenic risk scores were not available.

CONCLUSIONS

Exposure to cumulative psychosocial family risks from early childhood is associated with early indicators of problem behavior in adolescence.

Genetic analysis of the cooperative tumorigenic effects of targeted deletions of tumor suppressors Rb1, Trp53, Men1, and Pten in neuroendocrine tumors in mice

Genetic alterations of tumor suppressor genes (TSGs) are frequently observed to have cumulative or cooperative tumorigenic effects. We examined whether the TSGs Rb1, Trp53, Pten and Men1 have cooperative effects in suppressing neuroendocrine tumors (NETs) in mice. We generated pairwise homozygous deletions of these four genes in insulin II gene expressing cells using the Cre-LoxP system. By monitoring growth and examining the histopathology of the pituitary (Pit) and pancreas (Pan) in these mice, we demonstrated that pRB had the strongest cooperative function with PTEN in suppressing PitNETs and had strong cooperative function with Menin and TRP53, respectively, in suppressing PitNETs and PanNETs. TRP53 had weak cooperative function with PTEN in suppressing pituitary lesions. We also found that deletion of Pten singly led to prolactinomas in female mice, and deletion of Rb1 alone led to islet hyperplasia in pancreas. Collectively, our data indicated that pRB and PTEN pathways play significant roles in suppressing PitNETs, while the Menin-mediated pathway plays a significant role in suppressing PanNETs. Understanding the molecular mechanisms of these genes and pathways on NETs will help us understand the molecular mechanisms of neuroendocrine tumorigenesis and develop effective preclinical murine models for NET therapeutics to improve clinical outcomes in humans.

Shared Reading at Age 1 Year and Later Vocabulary: A Gene-Environment Study

OBJECTIVE

To assess the extent to which associations between shared reading at age 1 years and child vocabulary at age 3 years differ based on the presence of sensitizing alleles in the dopaminergic and serotonergic neurotransmitter systems.

STUDY DESIGN

We conducted a secondary analysis of data from a national urban birth cohort using mother reports in conjunction with child assessments and salivary genetic data. Child vocabulary was assessed using the Peabody Picture Vocabulary Test. The primary exposure was mother-reported shared reading. We used data on gene variants that may affect the function of the dopaminergic and serotonergic systems. We examined associations between shared reading and Peabody Picture Vocabulary Test score using multiple linear regression. We then included interaction terms between shared reading and the presence of sensitizing alleles for each polymorphism to assess potential moderator effects adjusting for multiple comparisons.

RESULTS

Of the 1772 children included (56% black, 52% male), 31% of their mothers reported reading with their child daily. Daily shared reading was strongly associated with child Peabody Picture Vocabulary Test scores in unadjusted (B = 7.9; 95% CI, 4.3-11.4) and adjusted models (B = 5.3; 95% CI, 2.0-8.6). The association differed based on the presence of sensitizing alleles in the dopamine receptor 2 and serotonin transporter genes.

CONCLUSIONS

Among urban children, shared reading at age 1 years was associated with greater vocabulary at age 3 years. Although children with sensitizing alleles on the dopamine receptor 2 and serotonin transporter genes were at greater risk when not read to, they fared as well as children without these alleles when shared reading occurred.

Functional outcomes among survivors of pediatric in-hospital cardiac arrest are associated with baseline neurologic and functional status, but not with diastolic blood pressure during CPR

AIM

Diastolic blood pressure (DBP) during cardiopulmonary resuscitation (CPR) is associated with survival following pediatric in-hospital cardiac arrest. The relationship between intra-arrest haemodynamics and neurological status among survivors of pediatric cardiac arrest is unknown.

METHODS

This study represents analysis of data from the prospective multicenter Pediatric Intensive Care Quality of cardiopulmonary resuscitation (PICqCPR) Study. Primary predictor variables were median DBP and median systolic blood pressure (SBP) over the first 10min of CPR. The primary outcome measure was "new substantive morbidity" determined by Functional Status Scale (FSS) and defined as an increase in the FSS of at least 3 points or increase of 2 in a single FSS domain. Univariable analyses were completed to investigate the relationship between new substantive morbidity and BPs during CPR.

RESULTS

244 index CPR events occurred during the study period, 77 (32%) CPR events met all inclusion criteria as well as having both DBP and FSS data available. Among 77 survivors, 32 (42%) had new substantive morbidity as measured by the FSS score. No significant differences were identified in DBP (median 30.5mmHg vs. 30.9mmHg, p=0.5) or SBP (median 76.3mmHg vs. 63.0mmHg, p=0.2) between patients with and without new substantive morbidity. Children who developed new substantive morbidity were more likely to have lower pre-arrest FSS than those that did not (median [IQR]: 7.5 [6.0-9.0] versus 9.0 [7.0-13.0], p=0.01).

CONCLUSION

New substantive morbidity determined by FSS after a pediatric IHCA was associated with baseline functional status, but not DBP during CPR.

The association of immediate post cardiac arrest diastolic hypertension and survival following pediatric cardiac arrest

AIM

In-hospital cardiac arrest occurs in >5000 children each year in the US and almost half will not survive to discharge. Animal data demonstrate that an immediate post-resuscitation burst of hypertension is associated with improved survival. We aimed to determine if systolic and diastolic invasive arterial blood pressures immediately (0-20 min) after return of spontaneous circulation (ROSC) are associated with survival and neurologic outcomes at hospital discharge.

METHODS

This is a secondary analysis of the Pediatric Intensive Care Quality of CPR (PICqCPR) study of invasively measured blood pressures during intensive care unit CPR. Patients were eligible if they achieved ROSC and had at least one invasively measured blood pressure within the first 20 min following ROSC. Post-ROSC blood pressures were normalized for age, sex and height. "Immediate hypertension" was defined as at least one systolic or diastolic blood pressure >90th percentile. The primary outcome was survival to hospital discharge.

RESULTS

Of 102 children, 70 (68.6%) had at least one episode of immediate post-CPR diastolic hypertension. After controlling for pre-existing hypotension, duration of CPR, calcium administration, and first documented rhythm, patients with immediate post-CPR diastolic hypertension were more likely to survive to hospital discharge (79.3% vs. 54.5%; adjusted OR = 2.93; 95%CI, 1.16-7.69).

CONCLUSIONS

In this post hoc secondary analysis of the PICqCPR study, 68.6% of subjects had diastolic hypertension within 20 min of ROSC. Immediate post-ROSC hypertension was associated with increased odds of survival to discharge, even after adjusting for covariates of interest.

Two well-differentiated pancreatic neuroendocrine tumor mouse models

Multiple endocrine neoplasia type 1 (MEN1) is a genetic syndrome in which patients develop neuroendocrine tumors (NETs), including pancreatic neuroendocrine tumors (PanNETs). The prolonged latency of tumor development in MEN1 patients suggests a likelihood that other mutations cooperate with Men1 to induce PanNETs. We propose that Pten loss combined with Men1 loss accelerates tumorigenesis. To test this, we developed two genetically engineered mouse models (GEMMs)-MPR (Men1^flox/flox Pten^flox/flox RIP-Cre) and MPM (Men1^flox/flox Pten^flox/flox MIP-Cre) using the Cre-LoxP system with insulin-specific biallelic inactivation of Men1 and Pten. Cre in the MPR mouse model was driven by the transgenic rat insulin 2 promoter while in the MPM mouse model was driven by the knock-in mouse insulin 1 promoter. Both mouse models developed well-differentiated (WD) G1/G2 PanNETs at a much shorter latency than Men1 or Pten single deletion alone and exhibited histopathology of human MEN1-like tumor. The MPR model, additionally, developed pituitary neuroendocrine tumors (PitNETs) in the same mouse at a much shorter latency than Men1 or Pten single deletion alone as well. Our data also demonstrate that Pten plays a role in NE tumorigenesis in pancreas and pituitary. Treatment with the mTOR inhibitor rapamycin delayed the growth of PanNETs in both MPR and MPM mice, as well as the growth of PitNETs, resulting in prolonged survival in MPR mice. Our MPR and MPM mouse models are the first to underscore the cooperative roles of Men1 and Pten in cancer, particularly neuroendocrine cancer. The early onset of WD PanNETs mimicking the human counterpart in MPR and MPM mice at 7 weeks provides an effective platform for evaluating therapeutic opportunities for NETs through targeting the MENIN-mediated and PI3K/AKT/mTOR signaling pathways.

End-tidal carbon dioxide during pediatric in-hospital cardiopulmonary resuscitation

BACKGROUND

Based on laboratory cardiopulmonary resuscitation (CPR) investigations and limited adult data, the American Heart Association Consensus Statement on CPR Quality recommends titrating CPR performance to achieve end-tidal carbon dioxide (ETCO2) >20 mmHg.

AIMS

We prospectively evaluated whether ETCO2 > 20 mmHg during CPR was associated with survival to hospital discharge.

METHODS

Children ≥37 weeks gestation in Collaborative Pediatric Critical Care Research Network intensive care units with chest compressions for ≥1 min and ETCO2 monitoring prior to and during CPR between July 1, 2013 and June 31, 2016 were included. ETCO2 and Utstein-style cardiac arrest data were collected. Multivariable Poisson regression models with robust error estimates were used to estimate relative risk of outcomes.

RESULTS

Blinded investigators analyzed ETCO2 waveforms from 43 children. During CPR, the median ETCO2 was 23 mmHg [quartiles, 16 and 28 mmHg], median ventilation rate was 29 breaths/min [quartiles, 24 and 35 breaths/min], and median duration of CPR was 5 min [quartiles, 2 and 16 min]. Return of spontaneous circulation occurred after 71% of CPR events and 37% of patients survived to hospital discharge. For children with mean ETCO2 during CPR > 20 mmHg, the adjusted relative risk for survival was 0.92 (0.41, 2.08), p = 0.84. The median mean ETCO2 among children who survived to hospital discharge was 20 mmHg [quartiles; 15, 28 mmHg] versus 23 mmHg [16, 28 mmHg] among non-survivors.

CONCLUSION

Mean ETCO2 > 20 mmHg during pediatric in-hospital CPR was not associated with survival to hospital discharge, and ETCO2 was not different in survivors versus non-survivors.

Association Between Diastolic Blood Pressure During Pediatric In-Hospital Cardiopulmonary Resuscitation and Survival

BACKGROUND

On the basis of laboratory cardiopulmonary resuscitation (CPR) investigations and limited adult data demonstrating that survival depends on attaining adequate arterial diastolic blood pressure (DBP) during CPR, the American Heart Association recommends using blood pressure to guide pediatric CPR. However, evidence-based blood pressure targets during pediatric CPR remain an important knowledge gap for CPR guidelines.

METHODS

All children ≥37 weeks' gestation and <19 years old in Collaborative Pediatric Critical Care Research Network intensive care units with chest compressions for ≥1 minute and invasive arterial blood pressure monitoring before and during CPR between July 1, 2013, and June 31, 2016, were included. Mean DBP during CPR and Utstein-style standardized cardiac arrest data were collected. The hypothesis was that DBP ≥25 mm Hg during CPR in infants and ≥30 mm Hg in children ≥1 year old would be associated with survival. Primary outcome was survival to hospital discharge. Secondary outcome was survival to hospital discharge with favorable neurological outcome, defined as Pediatric Cerebral Performance Categories 1 to 3 or no worse than prearrest baseline. Multivariable Poisson regression models with robust error estimates were used to estimate the relative risk of outcomes.

RESULTS

Blinded investigators analyzed blood pressure waveforms during CPR from 164 children, including 60% <1 year old, 60% with congenital heart disease, and 54% after cardiac surgery. The immediate cause of arrest was hypotension in 67%, respiratory decompensation in 44%, and arrhythmia in 19%. Median duration of CPR was 8 minutes (quartiles, 3 and 27 minutes). Ninety percent survived the event, 68% with return of spontaneous circulation and 22% by extracorporeal life support. Forty-seven percent survived to hospital discharge, and 43% survived to discharge with favorable neurological outcome. Maintaining mean DBP ≥25 mm Hg in infants and ≥30 mm Hg in children ≥1 year old occurred in 101 of 164 children (62%) and was associated with survival (adjusted relative risk, 1.7; 95% confidence interval, 1.2-2.6; P=0.007) and survival with favorable neurological outcome (adjusted relative risk, 1.6; 95% confidence interval, 1.1-2.5; P=0.02).

CONCLUSIONS

These data demonstrate that mean DBP ≥25 mm Hg during CPR in infants and ≥30 mm Hg in children ≥1 year old was associated with greater likelihood of survival to hospital discharge and survival with favorable neurological outcome.

Improving outcomes after pediatric cardiac arrest - the ICU-Resuscitation Project: study protocol for a randomized controlled trial

Background

Quality of cardiopulmonary resuscitation (CPR) is associated with survival, but recommended guidelines are often not met, and less than half the children with an in-hospital arrest will survive to discharge. A single-center before-and-after study demonstrated that outcomes may be improved with a novel training program in which all pediatric intensive care unit staff are encouraged to participate in frequent CPR refresher training and regular, structured resuscitation debriefings focused on patient-centric physiology.

Methods/design

This ongoing trial will assess whether a program of structured debriefings and point-of-care bedside practice that emphasizes physiologic resuscitation targets improves the rate of survival to hospital discharge with favorable neurologic outcome in children receiving CPR in the intensive care unit. This study is designed as a hybrid stepped-wedge trial in which two of ten participating hospitals are randomly assigned to enroll in the intervention group and two are assigned to enroll in the control group for the duration of the trial. The remaining six hospitals enroll initially in the control group but will transition to enrolling in the intervention group at randomly assigned staggered times during the enrollment period.

Discussion

To our knowledge, this is the first implementation of a hybrid stepped-wedge design. It was chosen over a traditional stepped-wedge design because the resulting improvement in statistical power reduces the required enrollment by 9 months (14%). However, this design comes with additional challenges, including logistics of implementing an intervention prior to the start of enrollment. Nevertheless, if results from the single-center pilot are confirmed in this trial, it will have a profound effect on CPR training and quality improvement initiatives.

Trial registration

ClinicalTrials.gov, NCT02837497. Registered on July 19, 2016.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-2590-y) contains supplementary material, which is available to authorized users.

Neighborhood Disadvantage and Telomere Length: Results from the Fragile Families Study

Telomeres are repetitive nucleotide sequences located at the ends of chromosomes that protect genetic material. We use data from the Fragile Families and Child Wellbeing Study to analyze the relationship between exposure to spatially concentrated disadvantage and telomere length for white and black mothers. We find that neighborhood disadvantage is associated with shorter telomere length for mothers of both races. This finding highlights a potential mechanism through which the unique spatially concentrated disadvantage faced by African Americans contributes to racial health disparities. We conclude that equalizing the health and socioeconomic status of black and white Americans will be very difficult without reducing levels of residential segregation in the United States.

DNA methylation, early life environment, and health outcomes

Epigenetics, and especially DNA methylation, have recently become provocative biological explanations for early-life environmental effects on later health. Despite the large increase in papers on the topic over the last few years, many questions remain with regards to the biological feasibility of this mechanism and the strength of the evidence to date. In this review, we examine the literature on early-life effects on epigenetic patterns, with special emphasis on social environmental influences. First, we review the basic biology of epigenetic modification of DNA and debate the role of early-life stressful, protective, and positive environments on gene-specific, system-specific, and whole-genome epigenetic patterns later in life. Second, we compare the epigenetic literatures of both humans and other animals and review the research linking epigenetic patterns to health in order to complete the mechanistic pathway. Third, we discuss physical environmental and social environmental effects, which have to date, generally not been jointly considered. Finally, we close with a discussion of the current state of the area's research, its future direction, and its potential use in pediatric health.

Epigenetics and Understanding the Impact of Social Determinants of Health

Recently, a new research agenda emphasizing interactions between social factors and health has emerged. The term social determinant of health often refers to any nonmedical factor directly influencing health. Health across the life span is strongly and adversely affected by social disadvantage. Research in epigenetics indicates that alterations in DNA methylation may provide a causal link between social adversity and health disparity. Likewise, accelerated loss of telomeres is correlated with chronic stress. Research is still required to develop an understanding of the role of epigenetics and perturbed telomere function in linking social adversity with health outcome.

p63 regulates glutaminase 2 expression

The transcription factor p63 is critical for many biological processes, including development and maintenance of epidermal tissues and tumorigenesis. Here, we report that the TAp63 isoforms regulate cell metabolism through the induction of the mitochondrial glutaminase 2 (GLS2) gene both in primary cells and tumor cell lines. By ChIP analysis and luciferase assay, we confirmed that TAp63 binds directly to the p53/p63 consensus DNA binding sequence within the GLS2 promoter region. Given the critical role of p63 in epidermal differentiation, we have investigated the regulation of GLS2 expression during this process. GLS2 and TAp63 expression increases during the in vitro differentiation of primary human keratinocytes, and depletion of GLS2 inhibits skin differentiation both at molecular and cellular levels. We found that GLS2 and TAp63 expression are concomitantly induced in cancer cells exposed to oxidative stresses. siRNA-mediated depletion of GLS2 sensitizes cells to ROS-induced apoptosis, suggesting that the TAp63/GLS2 axis can be functionally important as a cellular antioxidant pathway in the absence of p53. Accordingly, we found that GLS2 is upregulated in colon adenocarcinoma. Altogether, our findings demonstrate that GLS2 is a bona fide TAp63 target gene, and that the TAp63-dependent regulation of GLS2 is important for both physiological and pathological processes.

Targeted deletion of Nm23/nucleoside diphosphate kinase A and B reveals their requirement for definitive erythropoiesis in the mouse embryo

The ubiquitously expressed nucleoside diphosphate kinases (Nm23/NDPK/Awd) are a large family of multifunctional enzymes implicated in nucleic acid metabolism and in normal and abnormal development. Here, we describe the generation and characterization of NDPK A- and B-deficient (Nme1(-/-)/Nme2(-/-)) mice in which >95% of the enzyme activity is eliminated. These mice are undersized, die perinatally, and exhibit a spectrum of hematological phenotypes including severe anemia, impaired maturation of erythrocytes, and abnormal hematopoiesis in the liver and bone marrow. Flow cytometric analysis of developing Nme1(-/-)/Nme2(-/-) erythroid cells indicated that the major iron transport receptor molecule TfR1 is attenuated concomitant with a reduction of intracellular iron, suggesting that TfR1 is a downstream target of NDPKs and that reduced iron in Nme1(-/-)/Nme2(-/-) erythroblasts is inhibiting their development. We conclude that Nm23/NDPKs play critical roles in definitive erythroid development. Our novel mouse model also links erythropoiesis and nucleotide metabolism.

Emerging paradigms in cancer genetics: some important findings from high-density single nucleotide polymorphism array studies

High-density single nucleotide polymorphism (SNP) mapping arrays have identified chromosomal features whose importance to cancer predisposition and progression is not yet clearly defined. Of interest is that the genomes of normal somatic cells (reflecting the combined parental germ-line contributions) often contain long homozygous stretches. These chromosomal segments may be explained by the common ancestry of the individual's parents and thus may also be called autozygous. Several studies link consanguinity to higher rates of cancer, suggesting that autozygosity (a genomic consequence of consanguinity) may be a factor in cancer predisposition. SNP array analysis has also identified chromosomal regions of somatic uniparental disomy (UPD) in cancer genomes. These are chromosomal segments characterized by loss of heterozygosity (LOH) and a normal copy number (two) but which are not autozygous in the germ-line or normal somatic cell genome. In this review, we will also discuss a model [cancer gene activity model (CGAM)] that may explain how autozygosity influences cancer predisposition. CGAM can also explain how the occurrence of certain chromosomal aberrations (copy number gain, LOH, and somatic UPDs) during carcinogenesis may be dependent on the germ-line genotypes of important cancer-related genes (oncogenes and tumor suppressors) found in those chromosomal regions.

CpG island methylator phenotype associates with low-degree chromosomal abnormalities in colorectal cancer

PURPOSE

Aberrant promoter methylation and genomic instability occur frequently during colorectal cancer development. CpG island methylator phenotype (CIMP) has been shown to associate with microsatellite instability, and BRAF mutation and is often found in the right-side colon. Nevertheless, the relative importance of CIMP and chromosomal instability (CIN) for tumorigenesis has yet to be thoroughly investigated in sporadic colorectal cancers.

EXPERIMENTAL DESIGN

We determined CIMP in 161 primary colorectal cancers and 66 matched normal mucosae using a quantitative bisulfite/PCR/ligase detection reaction (LDR)/Universal Array assay. The validity of CIMP was confirmed in a subset of 60 primary tumors using MethyLight assay and five independent markers. In parallel, CIN was analyzed in the same study cohort using Affymetrix 50K Human Mapping arrays.

RESULTS

The identified CIMP-positive cancers correlate with microsatellite instability (P = 0.075) and the BRAF mutation V600E (P = 0.00005). The array-based high-resolution analysis of chromosomal aberrations indicated that the degree of aneuploidy is spread over a wide spectrum among analyzed colorectal cancers. Whether CIN was defined by copy number variations in selected microsatellite loci (criterion 1) or considered as a continuous variable (criterion 2), CIMP-positive samples showed a strong correlation with low-degree chromosomal aberrations (P = 0.075 and P = 0.012, respectively). Similar correlations were observed when CIMP was determined by MethyLight assay (P = 0.001 and P = 0.013, respectively).

CONCLUSION

CIMP-positive tumors generally possess lower chromosomal aberrations, which may only be revealed using a genome-wide approach. The significant difference in the degree of chromosomal aberrations between CIMP-positive and the remainder of samples suggests that epigenetic (CIMP) and genetic (CIN) abnormalities may arise from independent molecular mechanisms of tumor progression.

The signatures of autozygosity among patients with colorectal cancer

Previous studies have shown that among populations with a high rate of consanguinity, there is a significant increase in the prevalence of cancer. Single nucleotide polymorphism (SNP) array data (Affymetrix, 50K XbaI) analysis revealed long regions of homozygosity in genomic DNAs taken from tumor and matched normal tissues of colorectal cancer (CRC) patients. The presence of these regions in the genome may indicate levels of consanguinity in the individual's family lineage. We refer to these autozygous regions as identity-by-descent (IBD) segments. In this study, we compared IBD segments in 74 mostly Caucasian CRC patients (mean age of 66 years) to two control data sets: (a) 146 Caucasian individuals (mean age of 80 years) who participated in an age-related macular degeneration (AMD) study and (b) 118 cancer-free Caucasian individuals from the Framingham Heart Study (mean age of 67 years). Our results show that the percentage of CRC patients with IBD segments (>or=4 Mb length and 50 SNPs probed) in the genome is at least twice as high as the AMD or Framingham control groups. Also, the average length of these IBD regions in the CRC patients is more than twice the length of the two control data sets. Compared with control groups, IBD segments are found to be more common among individuals of Jewish background. We believe that these IBD segments within CRC patients are likely to harbor important CRC-related genes with low-penetrance SNPs and/or mutations, and, indeed, two recently identified CRC predisposition SNPs in the 8q24 region were confirmed to be homozygous in one particular patient carrying an IBD segment covering the region.

Determination of dual effects of parathyroid hormone on skeletal gene expression in vivo by microarray and network analysis

Parathyroid hormone (PTH) stimulates bone formation when injected daily but causes severe bone loss with continuous infusion. The mechanism of its paradoxical effects is still elusive. In this study, we compared changes in the gene expression profile in bone induced by intermittent or continuous treatment with three different PTH peptides, PTH-(1-34), -(1-31), and -(3-34), in Sprague-Dawley female rats. PTH-(1-34) regulated numerous genes (approximately 1,000), but differentially, in both regimes. PTH-(1-31) regulated a similar number of genes in the intermittent regimen but fewer in the continuous regimen, consistent with its less potent catabolic effect. PTH-(3-34) regulated very few genes in both regimes, which suggests the protein kinase C pathway plays a limited role in mediating the dual effects of PTH, whereas the cAMP-dependent protein kinase A pathway appears to predominate. In the intermittent treatment, many genes encoding signaling mediators, transcription factors, cytokines, and proteases/protease inhibitors are regulated rapidly and cyclically with each PTH injection; genes associated with skeletal development show a slowly accruing pattern of expression. With continuous treatment, some genes are regulated from 6 h, and the mRNA levels are sustained with a longer infusion, whereas others show a kinetic decrease and then increase later. Significant up-regulation of genes stimulating osteoclastogenesis in the anabolic regime suggests a provocative and paradoxical theme for the anabolic effect of PTH that a full anabolic response requires a transient up-regulation of genes classically associated with a resorptive response. Ingenuity pathway analysis was performed on the microarray data. A novel signaling network was established that is differentially regulated in the two PTH treatment regimes. Key regulators are suggested to be AREG, CCL2, WNT4, and cAMP-responsive element modulator.