Consideration of pyloric stenosis as a cause of feeding dysfunction in children with cyanotic heart disease

Feeding difficulty has been reported at a higher incidence in infants with cyanotic heart disease and single ventricle physiology necessitating specialized feeding strategies. However, structural causes of feed intolerance in this subset of patients should not be ignored. This case series highlights three recent cases of pyloric stenosis in infants with left-sided obstructive lesions at our institution. In all three cases, the initial presumed diagnosis was feeding intolerance related to heart disease, and there was significant clinical improvement following identification and correction of pyloric stenosis

Does the degree of preoperative mitral regurgitation predict survival or the need for mitral valve repair or replacement in patients with anomalous origin of the left coronary artery from the pulmonary artery?

BackgroundAnomalous origin of the left coronary artery from the pulmonary artery causes severe myocardial ischemia, global left ventricular dysfunction, and annular dilatation producing varying degrees of mitral regurgitation. Mitral regurgitation secondary to the left ventricular or papillary muscle dysfunction in infants will usually improve in the absence of ongoing ischemia. The aim of this study is to determine the influence of the degree of preoperative mitral regurgitation on the early and late outcomes of patients with anomalous origin of the left coronary artery from the pulmonary artery who underwent coronary reimplantation.MethodsTwenty-five patients underwent coronary reimplantation and 1 early patient had ligation during a 30-year period (median age, 4 months; range, 1 month to 16 years), with a median follow-up of 7 years (range, 4 months to 25 years). Before repair, 7 infants (27%) presented in extremis requiring ventilatory and inotropic support, and 17 patients (65%) presented with heart failure. Mitral regurgitation was present in all patients: trivial in 6 patients, mild in 12 patients, moderate in 5 patients, and severe in 3 patients. No patient underwent mitral valve repair or replacement at the time of anomalous origin of the left coronary artery from the pulmonary artery repair.ResultsHospital survival was 92%. Three patients underwent mitral valve repair or replacement at the mean time of 3.5 years (all with severe preoperative mitral regurgitation). The degree of mitral regurgitation gradually improved in all remaining patients with preoperative mild and moderate mitral regurgitation. Echocardiographic studies demonstrated improvement in left ventricular function in all children. None of the patients showed any evidence of supravalvar pulmonary stenosis as a result of their pulmonary artery reconstruction.ConclusionLong-term clinical outcome and left ventricular function are good despite severe left ventricular dysfunction at presentation. Mitral valve repair or replacement is generally not necessary at the time of anomalous origin of the left coronary artery from the pulmonary artery repair. Significant residual mitral regurgitation is present in some patients and can usually be managed surgically at a later date depending on its degree of severity

Noncompaction cardiomyopathy and heterotaxy syndrome

Left ventricular noncompaction cardiomyopathy (LVNC) is characterized by compact and trabecular layers of the left ventricular myocardium. This cardiomyopathy may occur with congenital heart disease (CHD). Single cases document co-occurrence of LVNC and heterotaxy, but no data exist regarding the prevalence of this association. This study sought to determine whether a non-random association of LVNC and heterotaxy exists by evaluating the prevalence of LVNC in patients with heterotaxy. In a retrospective review of the Indiana Network for Patient Care, we identified 172 patients with heterotaxy (69 male, 103 female). Echocardiography and cardiac magnetic resonance imaging results were independently reviewed by two cardiologists to ensure reproducibility of LVNC. A total of 13/172 (7.5%) patients met imaging criteria for LVNC. The CHD identified in this subgroup included atrioventricular septal defects [11], dextrocardia [10], systemic and pulmonary venous return abnormalities [7], and transposition of the great arteries [5]. From this subgroup, 61% (n = 8) of the patients developed arrhythmias; and 61% (n = 8) required medical management for chronic heart failure. This study indicates that LVNC has increased prevalence among patients with heterotaxy when compared to the general population (0.014–1.3%) suggesting possible common genetic mechanisms. Interestingly, mice with a loss of function of Scrib or Vangl2 genes showed abnormal compaction of the ventricles, anomalies in cardiac looping, and septation defects in previous studies. Recognition of the association between LVNC and heterotaxy is important for various reasons. First, the increased risk of arrhythmias demonstrated in our population. Secondly, theoretical risk of thromboembolic events remains in any LVNC population. Finally, many patients with heterotaxy undergo cardiac surgery (corrective and palliative) and when this is associated with LVNC, patients should be presumed to incur a higher peri-operative morbidity based on previous studies. Further research will continue to determine long-term and to corroborate genetic pathways

Insect herbivory (Choristoneura fumiferana, Tortricidea) underlies tree population structure (Picea glauca, Pinaceae)

Variation in insect herbivory can lead to population structure in plant hosts as indicated by defence traits. In annual herbaceous, defence traits may vary between geographic areas but evidence of such patterns is lacking for long-lived species. This may result from the variety of selection pressures from herbivores, long distance gene flow, genome properties, and lack of research. We investigated the antagonistic interaction between white spruce (Picea glauca) and spruce budworm (SBW, Choristoneura fumiferana) the most devastating forest insect of eastern North America in common garden experiments. White spruces that are able to resist SBW attack were reported to accumulate the acetophenones piceol and pungenol constitutively in their foliage. We show that levels of these acetophenones and transcripts of the gene responsible for their release is highly heritable and that their accumulation is synchronized with the most devastating stage of SBW. Piceol and pungenol concentrations negatively correlate with rate of development in female SBW and follow a non-random geographic variation pattern that is partially explained by historical damage from SBW and temperature. Our results show that accumulation of acetophenones is an efficient resistance mechanism against SBW in white spruce and that insects can affect population structure of a long-lived plant

Echocardiographic Guidance During Neonatal and Pediatric Jugular Cannulation for ECMO

Background Internal jugular vein extracorporeal membrane oxygenation (ECMO) cannula position is traditionally confirmed via plain film. Misplaced cannulae can result in need for repositioning and increased morbidity. Echocardiography (ECHO) may be used during cannulation as a more accurate means of guiding cannula position. This study reviews the effect of a protocol encouraging the use of ECHO at cannulation. Methods and materials Single institution retrospective review of patients who received ECMO support using jugular venous cannulation. We compared those who underwent ECHO (ECHO+) at the time of cannulation with those who did not (ECHO−). Results Eighty-nine patients were included: 26 ECHO+, 63 ECHO−. Most ECHO+ patients underwent dual-lumen veno-venous (VV) cannulation (65%); 32% of ECHO− patients had VV support (P = 0.003). There was no difference in the rate of cannula repositioning between the two groups: 8% ECHO+ and 10% ECHO−, P = 0.78. In the VV ECMO subgroup, ECHO+ patients required no repositioning (0/17), while 20% (4/20) of ECHO− VV patients did (P = 0.10). After cannulation, there were 0.58 ECHO studies per patient to verify cannula position in the ECHO+ group compared with 0.22 in the ECHO− group (P = 0.02). Each group had a major mechanical complication: atrial perforation from a guidewire during cannulation in ECHO+ and late atrial perforation from a loose cannula in ECHO−, and there was no difference in minor complications. Conclusions ECHO guidance during neonatal and pediatric jugular cannulation for ECMO did not decrease morbidity or reduce the need for cannula repositioning. ECHO may still be a useful adjunct for precise placement of a dual-lumen VV cannula and during difficult cannulations

Effects of Tanglehead Expansion on Bobwhite Habitat Use in South Texas

Usable space for northern bobwhite (Colinus virginianus) has been reduced across a large portion of South Texas rangelands due to the spread of non-native, invasive grasses. A native grass, tanglehead (Heteropogon contortus) has rapidly expanded its dominance in the western Sand Sheet of South Texas within the last 10-15 years. It has formed high-density monocultures, similar to non-native grasses, which are associated with losses of forb and grass diversity as well as bare ground, which are key components of bobwhite habitat. The objectives of our research were to 1) determine selection-avoidance of habitat features by bobwhites, and 2) determine the effects of tanglehead cover on vegetation characteristics. We detected 488 coveys across 20,103 ha on helicopter surveys conducted December 2014 in South Texas. We measured 6 vegetation characterstics (grass and forb species richness, vegetation height, woody-plant cover, tanglehead cover, and non-native grass cover) at all covey detections and an equal number of random locations. We developed continuous selection ratios based on probability density functions of used and random points derived using Simple Saddlepoint Approximations to determine habitat selection by bobwhites. We also used quantile regression at the 10th, 50th, and 90th quantiles to determine relationships between tanglehead and vegetation factors. Bobwhite avoided areas of high canopy cover (\u3e20%) of all invasive grasses measured. Brush cover was selected for up to 47%, after which it was avoided. We found significant negative relationships between tanglehead cover and forb and grass species richness, bare ground, and shrub cover, and a positive relationship with vegetation height at all quantiles modeled. Our results demonstrate the negative effects of increased tanglehead cover on native rangeland habitats. Further expansion by tanglehead has the potential to significantly reduce usable space for bobwhites in South Texas

Landscape-Scale Effects of Habitat and Weather on Scaled Quail Populations

Scaled quail (Callipepla squamata) have declined over the last half century; however, there is spatial variation within their geographic distribution. Interior populations have increased and peripheral populations have generally decreased. Declines have been attributed to habitat loss and degradation. Scaled quail populations also show interannual fluctuations related to precipitation. Our objective was to determine the relative impact of habitat and weather (i.e., precipitation and temperature) on scaled quail population dynamics. Our hypothesis was that habitat metrics would be more important for decreasing populations whereas weather metrics would be more important for increasing populations. We used publicly available datasets for scaled quail abundance measures (Breeding Bird Survey, Christmas Bird Count), weather (PRISM), and land cover (National Land Cover Data) collected over 3 5-year time periods (1990–1994, 1999–2003, 2009–2013). Data were collected at 2 scales: a route scale (5-km route buffer) and region scale (25-km circular buffer). We developed 25 a priori models that fit into 4 “model classes” (habitat amount, habitat fragmentation, matrix quality, weather). Model selection followed a 2-stage approach, where models were initially evaluated within each individual model class, then top models from each class were evaluated in combination to determine a global model. We used mixed-effects models with a negative binomial response distribution, treating route as a random effect. Weather variables were the primary explanatory factor for increasing populations at both scales. Similarly following our hypothesis, habitat variables were generally the most important for decreasing populations, but only at the route scale; weather variables dominated at the region scale. Both abundance datasets provided similar results and explanatory power (R2 ≈ 0.10 for route scale; R2 ≈ 0.27 for region scale), for both increasing and decreasing populations. Comparisons of land cover variables showed increasing populations to have higher amounts of habitat (p = 0.0028), higher mean patch area of habitat (p = 0.0446), and lower urban cover (p = 0.0287). Our hypothesis that weather variables account for more variation of increasing scaled quail populations was generally supported, likely because of increased amounts of habitat in these areas. However, given the low overall explanatory power of our models, it is likely that other factors such as habitat quality may be more important to scaled quail. Increasing temperature and reduced precipitation associated with climate change are likely to exacerbate scaled quail declines both directly and through continued habitat degradation, even within areas with increasing populations

Management of Complications Caused By a Massive Left Ventricle Tumor in a Neonate

We report a case of a neonate born with a giant fibroma occupying the entirety of her left ventricle. Due to the extensive resection, her postoperative course was complicated by severely diminished left ventricular function and complete heart block necessitating extracorporeal support. Ultimately, cardiac resynchronization therapy was employed, after which the infant’s ventricular function gradually improved and she was successfully discharged to home

Landscape of stimulation-responsive chromatin across diverse human immune cells.

A hallmark of the immune system is the interplay among specialized cell types transitioning between resting and stimulated states. The gene regulatory landscape of this dynamic system has not been fully characterized in human cells. Here we collected assay for transposase-accessible chromatin using sequencing (ATAC-seq) and RNA sequencing data under resting and stimulated conditions for up to 32 immune cell populations. Stimulation caused widespread chromatin remodeling, including response elements shared between stimulated B and T cells. Furthermore, several autoimmune traits showed significant heritability in stimulation-responsive elements from distinct cell types, highlighting the importance of these cell states in autoimmunity. Allele-specific read mapping identified variants that alter chromatin accessibility in particular conditions, allowing us to observe evidence of function for a candidate causal variant that is undetected by existing large-scale studies in resting cells. Our results provide a resource of chromatin dynamics and highlight the need to characterize the effects of genetic variation in stimulated cells

Evidence for Altered Basal Ganglia-Brainstem Connections in Cervical Dystonia

Background: There has been increasing interest in the interaction of the basal ganglia with the cerebellum and the brainstem in motor control and movement disorders. In addition, it has been suggested that these subcortical connections with the basal ganglia may help to coordinate a network of regions involved in mediating posture and stabilization. While studies in animal models support a role for this circuitry in the pathophysiology of the movement disorder dystonia, thus far, there is only indirect evidence for this in humans with dystonia. Methodology/Principal Findings: In the current study we investigated probabilistic diffusion tractography in DYT1-negative patients with cervical dystonia and matched healthy control subjects, with the goal of showing that patients exhibit altered microstructure in the connectivity between the pallidum and brainstem. The brainstem regions investigated included nuclei that are known to exhibit strong connections with the cerebellum. We observed large clusters of tractography differences in patients relative to healthy controls, between the pallidum and the brainstem. Tractography was decreased in the left hemisphere and increased in the right hemisphere in patients, suggesting a potential basis for the left/right white matter asymmetry we previously observed in focal dystonia patients. Conclusions/Significance: These findings support the hypothesis that connections between the basal ganglia and brainstem play a role in the pathophysiology of dystonia