Resource use differences of two coexisting chironomid species at localized scales.

Competing species may show positive correlations in abundance through time and space if they rely on a shared resource. Such positive correlations might obscure resource partitioning that facilitates competitor coexistence. Here, we examine the potential for resource partitioning between two ecologically similar midge species (Diptera: Chironomidae) in Lake Mývatn, Iceland. Tanytarsus gracilentus and Chironomus islandicus show large, roughly synchronized population fluctuations, implying potential reliance on a shared fluctuating resource and thereby posing the question of how these species coexist at high larval abundances. We first considered spatial partitioning of larvae. Abundances of both species were positively correlated in space; thus, spatial partitioning across different sites in the lake did not appear to be strong. We then inferred differences in dietary resources with stable carbon isotopes. T. gracilentus larvae had significantly higher δ13C values than C. islandicus, suggesting interspecific differences in resource use. Differences in resource selectivity, tube-building behavior, and feeding styles may facilitate resource partitioning between these species. Relative to surface sediments, T. gracilentus had higher δ13C values, suggesting that they selectively graze on 13C-enriched resources such as productive algae from the surface of their tubes. In contrast, C. islandicus had lower δ13C values than surface sediments, suggesting reliance on 13C-depleted resources that may include detrital organic matter and associated microbes that larvae selectively consume from the sediment surface or within their burrow walls. Overall, our study illustrates that coexisting and ecologically similar species may show positive correlations in space and time while using different resources at fine spatial scales.

A Novel Mental Health Curriculum Pilot for Pediatric Cardiology Fellows: Preparing the Subspecialist to Expand the Team.

Mental health (MH) is an important, yet understudied area of care for patients with congenital heart disease (CHD). Pediatric subspecialty fellows believe MH should be within their scope of practice, but few feel confident in their ability to appropriately screen, evaluate, manage, and make treatment referrals for youth with CHD and concurrent MH concerns. A 6-session, didactic-based curriculum was designed by an interprofessional team of experts. It was administered to pediatric cardiology fellows over 9 months during two academic years. Topics included the following: Introduction to MH and CHD, MH Screening and Clinic-Based Interventions, Psychopharmacology, Delirium, Trauma-Informed Care, and Adult CHD and Transitional Care. An investigator-designed survey was developed to assess fellow comfort with MH knowledge, screening, and treatment recommendation domains. Twenty-three fellows participated with 14 completing the pre-post survey (58% participation, 11/17 in year 1, 3/6 in year 2). Most participants were in their first year of training (9/14, 57%). Overall, fellow comfort with MH topics increased significantly (mean score 2.89 ± 0.46 vs. 3.4 ± 0.4, p = 0.0005), with improved comfort in the MH knowledge (p = 0.003) and treatment recommendation domains (p = 0.001). A didactic-based MH curriculum improves the comfort of pediatric cardiology fellows to address the MH concerns of their patients. The topics in this curriculum will continue to be refined over time and could be generalized to training programs, both nationally and across pediatric specialties, to improve MH care for high-risk populations.

Mental Health Care for Children with Heart Disease and Their Families: Practical Approaches and Considerations for the Pediatric and Pediatric Cardiology Clinician.

Mental health conditions are a common comorbidity among children living with heart disease. Children with congenital heart disease are more likely to have a mental health condition than their unaffected peers or peers with other chronic illnesses, and mental health risk persists across their lifetime. While poorer mental health in adults with congenital heart disease is associated with worse overall health outcomes, the association between mental health and cardiac outcomes for children with heart disease remains unknown. Despite this, it is suspected that mental health conditions go undiagnosed in children with heart disease and that many affected children and adolescents do not receive optimal mental health care. In this article, we review mental health in congenital heart disease across the lifespan, across domains of care, and across diagnoses. Further directions to support mental health care for children and adolescents with heart disease include practical screening and access to timely referral and mental health resources.

Modeling antibody drug conjugate potential using a granzyme B antibody fusion protein.

BACKGROUND: Antibody drug conjugates (ADCs) constitute a promising class of targeted anti-tumor therapeutics that harness the selectivity of monoclonal antibodies with the potency of cytotoxic drugs. ADC development is best suited to initially screening antibody candidates for desired properties that potentiate target cell cytotoxicity. However, validating and producing an optimally designed ADC requires expertise and resources not readily available to certain laboratories. RESULTS: In this study, we propose a novel approach to help streamline the identification of potential ADC candidates by utilizing a granzyme B (GrB)-based antibody fusion protein (AFP) for preliminary screening. GrB is a non-immunogenic serine protease expressed by immune effector cells such as CD8 + T cells that induces apoptotic activity and can be leveraged for targeted cell killing. CONCLUSIONS: Our innovative model allows critical antibody parameters (including target cell binding, internalization, and cytotoxic potential) to be more reliably evaluated in vitro through the creation of an ADC surrogate. Successful incorporation of this AFP could also significantly expand and enhance ADC development pre-clinically, ultimately leading to the accelerated translation of ADC therapies for patients.

Disentangling the drivers of decadal body size decline in an insect population.

While climate warming is widely predicted to reduce body size of ectotherms, evidence for this trend is mixed. Body size depends not only on temperature but also on other factors, such as food quality and intraspecific competition. Because temperature trends or other long-term environmental factors may affect population size and food sources, attributing trends in average body size to temperature requires the separation of potentially confounding effects. We evaluated trends in the body size of the midge Tanytarsus gracilentus and potential drivers (water temperature, population size, and food quality) between 1977 and 2015 at Lake Mývatn, Iceland. Although temperatures increased at Mývatn over this period, there was only a slight (non-significant) decrease in midge adult body size, contrary to theoretical expectations. Using a state-space model including multiple predictors, body size was negatively associated with both water temperature and midge population abundance, and it was positively associated with 13 C enrichment of midges (an indicator of favorable food conditions). The magnitude of these effects were similar, such that simultaneous changes in temperature, abundance, and carbon stable isotopic signature could counteract each other in the long-term body size trend. Our results illustrate how multiple factors, all of which could be influenced by global change, interact to affect average ectotherm body size.

Experience with SGLT2 Inhibitors in Patients with Single Ventricle Congenital Heart Disease and Fontan Circulatory Failure.

Heart failure is the leading cause of morbidity and mortality in patients with Fontan circulation. Sodium-glucose-cotransporter 2 inhibitors (SGLT2i) have become a mainstay of heart failure therapy in adult patients, however, there remains a paucity of literature to describe its use in pediatric heart failure patients, especially those with single ventricle physiology. We describe our early experience using SGLT2i in patients with single ventricle congenital heart disease surgically palliated to the Fontan circulation. We conducted a single-center retrospective chart review of all patients with Fontan circulation who were initiated on an SGLT2i from January 1, 2022 to March 1, 2023. Patient demographics, diagnoses, clinical status, and other therapies were collected from the electronic medical record. During the study period, 14 patients (median age 14.5 years, range 2.0-26.4 years) with Fontan circulation were started on a SGLT2i. Mean weight was 54 kg (range 11.6-80.4 kg). Median follow-up since SGLT2i initiation was 4.1 months (range 13 days-7.7 months). Four patients had a systemic left ventricle and 10 had a systemic right ventricle. Half the patients had Fontan Circulatory Failure with reduced Ejection Fraction (FCFrEF) of the systemic ventricle and the other half had Fontan Circulatory Failure with preserved Ejection Fraction (FCFpEF) of the systemic ventricle. In addition, 3 patients experienced Protein Losing Enteropathy (PLE) and 2 patients had plastic bronchitis, one of whom also was diagnosed with chylothorax. There were no genitourinary infections, hypoglycemia, ketoacidosis, hypotension or other significant adverse effects noted in our patient population. One patient experienced significant diuresis and transient acute kidney injury. Patients with FCFrEF showed a decrease in natriuretic peptide levels. Given the lack of proven therapies, demonstrated benefits of SGLT2i in other populations, and some suggestion of efficacy in Fontan circulation, further study of SGTLT2i in patients with Fontan circulation is warranted.

Outcomes after initial heart failure consultation in Fontan patients.

BACKGROUND: Patients with Fontan failure are high-risk candidates for heart transplantation and other advanced therapies. Understanding the outcomes following initial heart failure consultation can help define appropriate timing of referral for advanced heart failure care. METHODS: This is a survey study of heart failure providers seeing any Fontan patient for initial heart failure care. Part 1 of the survey captured data on clinical characteristics at the time of heart failure consultation, and Part 2, completed 30 days later, captured outcomes (death, transplant evaluation outcome, and other interventions). Patients were classified as "too late" (death or declined for transplant due to being too sick) and/or "care escalation" (ventricular assist device implanted, inotrope initiated, and/or listed for transplant), within 30 days. "Late referral" was defined as those referred too late and/or had care escalation. RESULTS: Between 7/2020 and 7/2022, 77 Fontan patients (52% inpatient) had an initial heart failure consultation. Ten per cent were referred too late (6 were too sick for heart transplantation with one subsequent death, and two others died without heart transplantation evaluation, within 30 days), and 36% had care escalation (21 listed ± 5 ventricular assist device implanted ± 6 inotrope initiated). Overall, 42% were late referrals. Heart failure consultation < 1 year after Fontan surgery was strongly associated with late referral (OR 6.2, 95% CI 1.8-21.5, p=0.004). CONCLUSIONS: Over 40% of Fontan patients seen for an initial heart failure consultation were late referrals, with 10% dying or being declined for transplant within a month of consultation. Earlier referral, particularly for those with heart failure soon after Fontan surgery, should be encouraged.

Listeria-based vaccination against the pericyte antigen RGS5 elicits anti-vascular effects and colon cancer protection.

Colorectal cancer (CRC) remains a leading cause of cancer-related mortality despite efforts to improve standard interventions. As CRC patients can benefit from immunotherapeutic strategies that incite effector T cell action, cancer vaccines represent a safe and promising therapeutic approach to elicit protective and durable immune responses against components of the tumor microenvironment (TME). In this study, we investigate the pre-clinical potential of a Listeria monocytogenes (Lm)-based vaccine targeting the CRC-associated vasculature. CRC survival and progression are reliant on functioning blood vessels to effectively mediate various metabolic processes and oxygenate underlying tissues. We, therefore, advance the strategy of initiating immunity in syngeneic mouse models against the endogenous pericyte antigen RGS5, which is a critical mediator of pathological vascularization. Overall, Lm-based vaccination safely induced potent anti-tumor effects that consisted of recruiting functional Type-1-associated T cells into the TME and reducing tumor blood vessel content. This study underscores the promising clinical potential of targeting RGS5 against vascularized tumors like CRC.

Targeting the pericyte antigen DLK1 with an alpha type-1 polarized dendritic cell vaccine results in tumor vascular modulation and protection against colon cancer progression.

Despite the availability of various treatment options, colorectal cancer (CRC) remains a significant contributor to cancer-related mortality. Current standard-of-care interventions, including surgery, chemotherapy, and targeted agents like immune checkpoint blockade and anti-angiogenic therapies, have improved short-term patient outcomes depending on disease stage, but survival rates with metastasis remain low. A promising strategy to enhance the clinical experience with CRC involves the use of dendritic cell (DC) vaccines that incite immunity against tumor-derived blood vessels, which are necessary for CRC growth and progression. In this report, we target tumor-derived pericytes expressing DLK1 with a clinically-relevant alpha type-1 polarized DC vaccine (αDC1) in a syngeneic mouse model of colorectal cancer. Our pre-clinical data demonstrate the αDC1 vaccine's ability to induce anti-tumor effects by facilitating cytotoxic T lymphocyte activity and ablating the tumor vasculature. This work, overall, provides a foundation to further interrogate immune-mediated mechanisms of protection in order to help devise efficacious αDC1-based strategies for patients with CRC.

Pediatric Heart Transplant Rejection After COVID-19 Infection.

BACKGROUND: Infections have been associated with rejection episodes in solid organ transplant recipients. We report an association between COVID-19 infection and heart transplant (HT) rejection. CASE DESCRIPTION: The patient was 14 years old and 6.5 years post-HT. He developed symptoms of rejection within 2 weeks of COVID exposure and presumed infection. CONCLUSIONS: In this case, COVID-19 infection closely preceded significant rejection and graft dysfunction. Further study is needed to establish a correlation between COVID-19 infection and rejection in HT patients.

Representation of Women and Minority Faculty and Fellows in Academic Pediatric Cardiology Training Programs.

BACKGROUND: Studies have shown that diverse care teams optimize patient outcomes. Describing the current representation of women and minorities has been a critical step in improving diversity across several fields. OBJECTIVES: To address the lack of data specific to pediatric cardiology, the authors conducted a national survey. METHODS: U.S. academic pediatric cardiology programs with fellowship training programs were surveyed. Division directors were invited (July 2021 to September 2021) to complete an e-survey of program composition. Underrepresented minorities in medicine (URMM) were characterized using standard definitions. Descriptive analyses at the hospital, faculty, and fellow level were performed. RESULTS: Altogether, 52 of 61 programs (85%) completed the survey, representing 1,570 total faculty and 438 fellows, with a wide range in program size (7-109 faculty, 1-32 fellows). Although women comprise approximately 60% of faculty in pediatrics overall, they made up 55% of fellows and 45% of faculty in pediatric cardiology. Representation of women in leadership roles was notably less, including 39% of clinical subspecialty directors, 25% of endowed chairs, and 16% of division directors. URMM comprise approximately 35% of the U.S. population; however, they made up only 14% of pediatric cardiology fellows and 10% of faculty, with very few in leadership roles. CONCLUSIONS: These national data suggest a "leaky pipeline" for women in pediatric cardiology and very limited presence of URRM overall. Our findings can inform efforts to elucidate underlying mechanisms for persistent disparity and reduce barriers to improving diversity in the field.

Paediatric cardiology training: burnout, fulfilment, and fears.

BACKGROUND: Burnout is well characterised in physicians and residents but not in paediatric cardiology fellows, and few studies follow burnout longitudinally. Training-specific fears have been described in paediatric cardiology fellows but also have not been studied at multiple time points. This study aimed to measure burnout, training-specific fears, and professional fulfilment in paediatric cardiology fellows with the attention to time of year and year-of-training. METHODS: This survey-based study included the Professional Fulfillment Index and the Impact of Events Scale as well as an investigator-designed Fellow Fears Questionnaire. Surveys were distributed at three-time points during the academic year to paediatric cardiology fellows at a large Midwestern training programme. Fellow self-reported gender and year-of-training were collected. Descriptive analyses were performed. RESULTS: 10/17 (59%) of fellows completed all surveys; 60% were female, 40% in the first-year class, 40% in the second-year class, and 20% in the third-year class. At least half of the fellows reported burnout at each survey time point, with lower mean professional fulfilment scores. The second-year class, who rotate primarily in the cardiac ICU, had higher proportions of burnout than the other two classes. At least half of fellows reported that they "often" or "always" worried about not having enough clinical knowledge or skills and about work-life balance. CONCLUSIONS: Paediatric cardiology fellows exhibit high proportions of burnout and training-specific fears. Interventions to mitigate burnout should be targeted specifically to training needs, including during high-acuity rotations.

Reconstructing midge consumer-resource dynamics using carbon stable isotope signatures of archived specimens.

Population cycles can be caused by consumer-resource interactions. Confirming the role of consumer-resource interactions, however, can be challenging due to an absence of data for the resource candidate. For example, interactions between midge larvae and benthic algae likely govern the high-amplitude population fluctuations of Tanytarsus gracilentus in Lake Mývatn, Iceland, but there are no records of benthic resources concurrent with adult midge population counts. Here, we investigate consumer population dynamics using the carbon stable isotope signatures of archived T. gracilentus specimens collected from 1977 to 2015, under the assumption that midge δ13 C values reflect those of resources they consumed as larvae. We used the time series for population abundance and δ13 C to estimate interactions between midges and resources while accounting for measurement error and possible preservation effects on isotope values. Results were consistent with consumer-resource interactions: high δ13 C values preceded peaks in the midge population, and δ13 C values tended to decline after midges reached high abundance. One interpretation of this dynamic coupling is that midge isotope signatures reflect temporal variation in benthic algal δ13 C values, which we expected to mirror primary production. Following from this explanation, high benthic production (enriched δ13 C values) would contribute to increased midge abundance, and high midge abundance would result in declining benthic production (depleted δ13 C values). An additional and related explanation is that midges deplete benthic algal abundance once they reach peak densities, causing midges to increase their relative reliance on other resources including detritus and associated microorganisms. Such a shift in resource use would be consistent with the subsequent decline in midge δ13 C values. Our study adds evidence that midge-resource interactions drive T. gracilentus fluctuations and demonstrates a novel application of stable isotope time-series data to understand consumer population dynamics.

Primary Disease, Sex, and Racial Differences in Health-Related Quality of Life in Adolescents and Young Adults with Heart Failure.

Health-related quality of life (HRQOL) is an important clinical and research trial endpoint in adult heart failure and has been shown to predict mortality and hospitalizations in adult heart failure populations. HRQOL has not been adequately studied in the growing pediatric and young adult heart failure population. This study described HRQOL in adolescents and young adults (AYAs) with heart failure and examined primary disease, sex, race, and other correlates of HRQOL in this sample. Participants in this cross-sectional, single-center study included adolescent and young adults with heart failure and a parent/guardian. Patients and their parent/proxies completed the PedsQL, a well-established measure of HRQOL in pediatric chronic illness populations. HRQOL is impaired in AYAs with heart failure resulting from dilated, hypertrophic, or other cardiomyopathy, congenital heart disease, or post-transplant with rejection/complications. Patients identifying as white endorsed poorer total HRQOL than non-white patients (p = 0.002). Subscale analysis revealed significant correlations between female sex (p = 0.01) and white race (p = 0.01) with poorer self-reported physical functioning. Family income was unrelated to HRQOL. Functional status was strongly associated with total (p = 0.0003) and physical HRQOL (p < 0.0001). Sociodemographic and disease-specific risk and resilience factors specific to HRQOL in AYAs with heart failure include primary cardiac disease, race, sex, and functional status. Building upon extensive work in adult heart failure, utilization, and study of HRQOL as a clinical and research trial outcome is necessary in pediatric heart failure. Developing targeted interventions for those at greatest risk of impaired HRQOL is an important next step.

Psychological functioning in paediatric patients with single ventricle heart disease: a systematic review.

BACKGROUND: Patients with single ventricle heart disease are living into adulthood due to medical and surgical advancements but have significant physical comorbidities and an increased risk for psychological comorbidities compared to healthy subjects or those with other CHD diagnoses. This study aimed to systematically review psychological functioning in paediatric single ventricle heart disease. METHODS: Literature was searched using PubMed, Embase, PsycInfo, CINAHL Complete and Scopus. Peer-reviewed articles that included patients ages 0-25 years with single ventricle heart disease, and quantitative measures of psychological outcomes were included. Meta-analysis using a fixed-effect model was conducted for internalising and externalising t-scores, utilised by the Achenbach Child Behavior Checklist. RESULTS: Twenty-nine records met the criteria for inclusion. 13/24 studies demonstrated increased risk for internalising disorders, such as anxiety/depression; 16/22 studies demonstrated risk for externalising disorders, such as attention or behavioural problems. Meta-analysis of four studies revealed that paediatric single ventricle heart disease patients had no significant difference in internalising and externalising t-scores compared to normative values. CONCLUSIONS: The current review demonstrates the need for further studies to better understand psychological functioning in patients with single ventricle heart disease, with a majority of studies showing increased risk for psychological problems despite no difference seen in a small meta-analysis. This summary of the literature underscores the need for regular psychological screening, earlier intervention and integrated mental health therapies in paediatric single ventricle heart disease.

Predictors and clinical significance of pericardial effusions after pediatric heart transplantation.

BACKGROUND: We aimed to describe the incidence, risk factors, and clinical outcomes of pericardial effusions within 6 months after pediatric heart transplantation (HT). METHODS: A single-center retrospective cohort study was performed on all pediatric HT recipients from 2004 to 2018. Logistic regression was used to identify factors associated with pericardial effusions post-HT, and survival was compared using log-rank test. RESULTS: During the study period, 97 HTs were performed in 93 patients. Fifty patients (52%) had a ≥small pericardial effusion within 6 months, 16 of which were, or became, ≥moderate in size. Pericardial drain was placed in 8 patients. In univariate analysis, larger recipient body surface area (p = .01) and non-congenital heart disease (p = .002) were associated with pericardial effusion development. Donor/recipient size ratios, post-HT hemodynamics, and rejection did not correlate with pericardial effusion development. In multivariable analysis, non-congenital heart disease (adjusted odds ratio 3.3, p = .01) remained independently associated with development of pericardial effusion. There were no significant differences in post-HT survival between patients with and without ≥small (p = .68) or ≥moderate pericardial effusions (p = .40). CONCLUSIONS: Pericardial effusions are common after pediatric HT. Patients with cardiomyopathy, or non-congenital heart disease, were at higher risk for post-HT pericardial effusions. Pericardial effusions increased morbidity but had no effect on mortality in our cohort. The risk factors identified may be used for anticipatory guidance in pediatric HT.

Ecosystem engineering alters density-dependent feedbacks in an aquatic insect population.

Ecosystem engineers have large impacts on the communities in which they live, and these impacts may feed back to populations of engineers themselves. In this study, we assessed the effect of ecosystem engineering on density-dependent feedbacks for midges in Lake Mývatn, Iceland. The midge larvae reside in the sediment and build silk tubes that provide a substrate for algal growth, thereby elevating benthic primary production. Benthic algae are in turn the primary food source for the midge larvae, setting the stage for the effects of engineering to feed back to the midges themselves. Using a field mesocosm experiment manipulating larval midge densities, we found a generally positive but nonlinear relationship between density and benthic production. Furthermore, adult emergence increased with the primary production per midge larva. By combining these two relationships in a simple model, we found that the positive effect of midges on benthic production weakened negative density dependence at low to intermediate larval densities. However, this benefit disappeared at high densities when midge consumption of primary producers exceeded their positive effects on primary production through ecosystem engineering. Our results illustrate how ecosystem engineering can alter density-dependent feedbacks for engineer populations.

Burnout, professional fulfillment, and post-traumatic stress among pediatric solid organ transplant teams.

BACKGROUND: Adverse effects of clinician burnout have been studied across multiple specialties; however, there have been no studies examining rates of burnout among pediatric solid organ transplant teams. This study aimed to measure burnout, work exhaustion, professional fulfillment, and post-traumatic stress symptoms among clinicians and administrators practicing in this high-stress field. METHODS: This cross-sectional study utilized a 50 item web-based survey that included the Personal Fulfillment Index and the IES-R. This survey was distributed across four pediatric solid organ transplant centers in North America. Basic demographics, clinician characteristics, and information regarding wellness and self-care activities were collected. Descriptive and correlational analyses were performed. RESULTS: One hundred and thirty five participants completed the survey, 76% were female and 78% were Caucasian. One-third (34%) of participants endorsed burnout, while 43% reported professional fulfillment. Approximately 15% of respondents endorsed clinically significant levels of post-traumatic stress symptoms related to patient deaths, with female clinicians more likely to endorse symptoms (p = .01). Nearly 80% of participants reported engaging in self-care activities outside of work and only 10% of participants reported participation in hospital-sponsored wellness programs. CONCLUSIONS: Pediatric solid organ transplant team members exhibited moderate levels of burnout, professional fulfillment, and post-traumatic stress. Female clinicians were the most likely to experience both work exhaustion and post-traumatic stress symptoms. Transplant centers are encouraged to consider interventions and programming to improve clinician wellness.

Psychosocial outcomes in pediatric patients with ventricular assist devices and their families: A systematic review.

Ventricular assist device (VAD) therapy has provided pediatric patients with severe heart failure new therapeutic options. However, pediatric patients and families receiving VAD therapy also experience psychosocial challenges. No synthesis of the literature on psychosocial outcomes within the pediatric VAD population has been conducted; thus, the current review sought to systematically investigate the impact of pediatric VAD on patient, parent, and family psychosocial outcomes and assess variables associated with poorer outcomes. Literature searches were conducted in PsycInfo, PubMed, and Cumulative Index to Nursing and Allied Health Literature databases and full texts were assessed according to pre-established inclusion criteria. Main findings and study quality were reviewed. Sixteen studies were included in the present review. Findings highlighted the likelihood for psychological sequelae among pediatric patients and families receiving VAD therapy, including decreased psychological and emotional well-being, elevated stress, and difficulty coping with changes to family dynamics and responsibilities. Health-related quality of life was reported comparable to that of healthy peers and children with other cardiac conditions. Patients and families on VAD therapy experience significant difficulties in psychological well-being and challenges related to adjustment. The current review underscores the importance of ongoing support for families and continued assessment of psychosocial functioning across VAD support. Three critical periods for increased distress were identified: 1) immediately following VAD implantation, 2) discharge home and the weeks following discharge, and 3) long-term VAD therapy.