4 results
Marked skeletal muscle deficits are associated with 6-minute walk distance in paediatric pulmonary hypertension
- Catherine M. Avitabile, Sofia Saavedra, Nithya Sivakumar, Elizabeth Goldmuntz, Stephen M. Paridon, Babette S. Zemel
-
- Journal:
- Cardiology in the Young / Volume 31 / Issue 9 / September 2021
- Published online by Cambridge University Press:
- 11 February 2021, pp. 1426-1433
-
- Article
- Export citation
-
Background:
Poor growth is common in children with pulmonary hypertension; however, skeletal muscle deficits have not been described and the association between muscle deficits and functional status is unknown.
Methods:Patients aged 8–18 years with pulmonary hypertension (diagnostic Groups 1, 2, or 3) and World Health Organization functional class I or II underwent dual-energy absorptiometry to measure leg lean mass Z-score (a surrogate for skeletal muscle). Muscle strength was assessed using dynamometry. Physical activity questionnaires were administered. Clinical data, including 6-minute walk distance, were reviewed. Relationships between skeletal muscle, physical activity score, and 6-minute walk distance were assessed by correlations and linear regression.
Results:Sixteen patients (12.1 ± 3.2 years, 50% female, 56% Group 1, 56% functional class II) were enrolled. Leg lean mass Z-score was significantly less than reference data (−1.40 ± 1.12 versus 0.0 ± 0.9, p < 0.001) and worse in those with functional class II versus I (−2.10 ± 0.83 versus −0.50 ± 0.73, p < 0.01). Leg lean mass Z-score was positively associated with right ventricular systolic function by tricuspid annular plane systolic Z-score (r = 0.54, p = 0.03) and negatively associated with indexed pulmonary vascular resistance (r = −0.78, p < 0.001). Leg lean mass Z-score and forearm strength were positively associated with physical activity score. When physical activity score was held constant, leg lean mass Z-score independently predicted 6-minute walk distance (R2 = 0.39, p = 0.03).
Conclusions:Youth with pulmonary hypertension demonstrate marked skeletal muscle deficits in association with exercise intolerance. Future studies should investigate whether low leg lean mass is a marker of disease severity or an independent target that can be improved.
4444 The effect of early life antibiotics on gut microbiome and fecal bile acid concentrations in children
- Alain Jesus Benitez, Jeffrey S. Gerber, Ceylan Tanes, Kyle Bittinger, Elliot S. Friedman, Hongzhe Li, Frederic D. Bushman, Gary D. Wu, Babette S. Zemel
-
- Journal:
- Journal of Clinical and Translational Science / Volume 4 / Issue s1 / June 2020
- Published online by Cambridge University Press:
- 29 July 2020, pp. 146-147
-
- Article
-
- You have access Access
- Open access
- Export citation
-
OBJECTIVES/GOALS: The current proposal seeks to investigate the effect of early life antibiotic use in the development of functional gastrointestinal (GI) disorders. We propose that infants exposed to antibiotics will present with gut microbial dysbiosis, changes in fecal bile acid concentrations and develop more GI symptoms compared to unexposed children. METHODS/STUDY POPULATION: We analyzed fecal samples from 174 subjects at 12 months of age, of whom 52 were exposed to antibiotics in their first year of life. Of these, 33 subjects were sampled again at 24 months of age. DNA from 200mg of frozen stool (−80C) was isolated with the Qiagen DNeasy PowerSoil kit. Shotgun libraries were generated using the NexteraXT kit and sequenced on the Illumina HiSeq 2500 using 2x125 bp chemistry. Sequence data were analyzed using the Sunbeam metagenomics pipeline. The abundance of bacteria was estimated using Kraken version 2.0.8. Fecal bile acids will be quantified by liquid chromatography–mass spectrometry (LC-MS). RESULTS/ANTICIPATED RESULTS: Overall bacterial community composition at 12 or 24 months was not associated with antibiotic exposure (PERMANOVA test, Bray-Curtis distance). An increase in Enterobacteriaceae, in particular Escherichia coli, is a signature of antibiotic-induced dysbiosis, but also of early infant gut. Children with antibiotic exposure had slightly higher abundance of Escherichia coli compared to those with no exposure (p = 0.03). At 24 months, the abundance of Bacteroides caccae, a commensal gut species, was decreased for children exposed to antibiotics in the first year of life (fdr = 0.02). We will perform further analysis of bile acid modifying bacteria, fecal bile acid concentrations and correlate to GI symptoms. DISCUSSION/SIGNIFICANCE OF IMPACT: Our findings suggest a significant but nuanced impact of early life antibiotic use on the composition of the gut microbiota. The association of antibiotic exposure with B. caccae and E. coli warrant further attention in the context of the rapidly developing early-life microbiome. CONFLICT OF INTEREST DESCRIPTION: The authors declare no conflicts of interest relevant to this work.
Abnormalities in serum biomarkers correlate with lower cardiac index in the Fontan population
- Bradley S. Marino, David J. Goldberg, Adam L. Dorfman, Eileen King, Heidi Kalkwarf, Babette S. Zemel, Margaret Smith, Jesse Pratt, Mark A. Fogel, Amanda J. Shillingford, Barbara J. Deal, Anitha S. John, Caren S. Goldberg, Timothy M. Hoffman, Marshall L. Jacobs, Asher Lisec, Susan Finan, Lazaros K. Kochilas, Thomas W. Pawlowski, Kathleen Campbell, Clinton Joiner, Stuart L. Goldstein, Paul Stephens, Jr, Alvin J. Chin
-
- Journal:
- Cardiology in the Young / Volume 27 / Issue 1 / January 2017
- Published online by Cambridge University Press:
- 05 July 2016, pp. 59-68
-
- Article
- Export citation
-
Background
Fontan survivors have depressed cardiac index that worsens over time. Serum biomarker measurement is minimally invasive, rapid, widely available, and may be useful for serial monitoring. The purpose of this study was to identify biomarkers that correlate with lower cardiac index in Fontan patients.
Methods and resultsThis study was a multi-centre case series assessing the correlations between biomarkers and cardiac magnetic resonance-derived cardiac index in Fontan patients ⩾6 years of age with biochemical and haematopoietic biomarkers obtained ±12 months from cardiac magnetic resonance. Medical history and biomarker values were obtained by chart review. Spearman’s Rank correlation assessed associations between biomarker z-scores and cardiac index. Biomarkers with significant correlations had receiver operating characteristic curves and area under the curve estimated. In total, 97 cardiac magnetic resonances in 87 patients met inclusion criteria: median age at cardiac magnetic resonance was 15 (6–33) years. Significant correlations were found between cardiac index and total alkaline phosphatase (−0.26, p=0.04), estimated creatinine clearance (0.26, p=0.02), and mean corpuscular volume (−0.32, p<0.01). Area under the curve for the three individual biomarkers was 0.63–0.69. Area under the curve for the three-biomarker panel was 0.75. Comparison of cardiac index above and below the receiver operating characteristic curve-identified cut-off points revealed significant differences for each biomarker (p<0.01) and for the composite panel [median cardiac index for higher-risk group=2.17 L/minute/m2 versus lower-risk group=2.96 L/minute/m2, (p<0.01)].
ConclusionsHigher total alkaline phosphatase and mean corpuscular volume as well as lower estimated creatinine clearance identify Fontan patients with lower cardiac index. Using biomarkers to monitor haemodynamics and organ-specific effects warrants prospective investigation.
6 - Measuring body composition
-
- By Babette Zemel, University of Pennsylvania School of Medicine, Elizabeth Barden, Massachusetts Department of Public Health
- Edited by Roland C. Hauspie, Vrije Universiteit, Amsterdam, Noël Cameron, Loughborough University, Luciano Molinari, Kinderspital Zürich
-
- Book:
- Methods in Human Growth Research
- Published online:
- 17 August 2009
- Print publication:
- 24 June 2004, pp 141-176
-
- Chapter
- Export citation
-
Summary
Introduction
The field of body composition research is a multidisciplinary effort that serves multiple goals. It is very technology oriented, and a great deal of effort is expended on discussion of the techniques, and their validation and cross-calibration. For studies involving infants, children and adolescents, this is of particular concern, because techniques that are of proven accuracy in adults may be fraught with error in children due to changes in the size and composition of body compartments during development. Consequently, standard approaches used in adults may not be applicable or safe for use with children. This review is targeted at techniques for assessing body composition, and includes a disproportionate discussion of those techniques most feasible and practical for use with children. Considerations of the methodological assumptions and of the analysis and presentation of body composition results for children also are reviewed.
Basic concepts
Body composition assessment involves quantification of the amount and relative proportions of fat, muscle and bone, and their chemical components. Significant changes in body composition occur during growth and development, especially during infancy and puberty. Thus, body composition assessment in children is far more challenging than in adults, and serves a variety of purposes. First, it provides a better understanding of growth processes by describing changes in the size of body compartments and the chemical composition of the body. Infants and children are not miniature adults, and knowledge of their unique differences in body composition is key to understanding the biology of the human species.