33 results on '"Felker, K."'
Search Results
2. (297) - Micro-RNA Biomarkers of Allograft Rejection in Pediatric Heart Transplantation
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Feingold, B., Rose-Felker, K., Mercado, A., Bagchi, P., Zinn, M., West, S., Miller, S., and Shah, P.
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- 2024
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3. Study of the properties of the superheavy nuclei Z = 117 produced in the 249Bk + 48Ca reaction
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Oganessian Yu. Ts., Abdullin F. Sh., Alexander C., Binder J., Boll R. A., Dmitriev S. N., Ezold J., Felker K., Gostic J. M., Grzywacz R. K., Hamilton J. H., Henderson R. A., Itkis M. G., Miernik K., Miller D., Moody K. J., Polyakov A. N., Ramayya A. V., Roberto J. B., Ryabinin M. A., Rykaczewski K. P., Sagaidak R. N., Shaughnessy D. A., Shirokovsky I. V., Shumeiko M. V., Stoyer M. A., Stoyer N. J., Subbotin V. G., Sukhov A. M., Tsyganov Yu. S., Utyonkov V. K., Voinov A. A., and Vostokin G. K.
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Physics ,QC1-999 - Abstract
The reaction of 249Bk with 48Ca have been reinvestigated to provide new evidence for the discovery of element 117 on a larger number of events. The experiments were performed at five projectile energies and with a total beam dose of 48Ca of about 4.6×1019. Two isotopes 293,294117 were synthesized in the 249Bk+48Ca reaction, providing excitation functions and α-decay spectra of the produced isotopes that establishes these nuclei to be the products of the 4n- and 3n-evaporation channels, respectively. Decay properties of 293,294117 and of all the daughter products agree with the data of the experiment in which these nuclei were synthesized for the first time in 2010. The new 289115 events, populated by α decay of 293117, demonstrate the same decay properties as those observed for 289115 produced in the 243Am(48Ca,2n) reaction thus providing crossbombardment evidence. In addition, a single decay of 294118 was observed from the reaction with 249Cf – a result of the in-growth of 249Cf in the 249Bk target.
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- 2014
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4. Alloantibody Reduction in Pediatric Heart Transplant Recipients
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Rose-Felker, K., Zinn, M., West, S.C., Miller, S.A., Mangiola, M., Zeevi, A., and Feingold, B.
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- 2019
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5. HLA Antibody Titer and C1Q Reactivity Reflect Response to Desensitization and Facilitate Donor Selection
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Mangiola, M., Zinn, M.D., West, S., Miller, S.A., Rose-Felker, K., Feingold, B., and Zeevi, A.
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- 2019
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6. (714) - Neutropenia in Pediatric Heart Transplant Recipients
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Rose-Felker, K., Mukhtar, A., Kelleman, M.S., Mahle, W.T., and Desphande, S.R.
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- 2017
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7. NEW RESULTS FOR ELEMENTS 115, 117, AND 118 PRODUCED IN THE REACTIONS 243Am+48Ca AND 249Bk/249Cf+48Ca.
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UTYONKOV, V. K., OGANESSIAN, YU. TS., ABDULLIN, F. SH., ALEXANDER, C., BINDER, J., BOLL, R. A., DMITRIEV, S. N., EZOLD, J., FELKER, K., GOSTIC, J. M., GRZYWACZ, R. K., HAMILTON, J. H., HENDERSON, R. A., ITKIS, M. G., MIERNIK, K., MILLER, D., MOODY, K. J., POLYAKOV, A. N., RAMAYYA, A. V., and ROBERTO, J. B.
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NUCLEAR reactions ,SUPERHEAVY elements ,NUCLEAR physics ,NUCLEAR matter ,ISOTOPES - Published
- 2013
8. (297) - Micro-RNA Biomarkers of Allograft Rejection in Pediatric Heart Transplantation.
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Goldberg, J., Feingold, B., Rose-Felker, K., Mercado, A., Bagchi, P., Zinn, M., West, S., Miller, S., and Shah, P.
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HEART transplantation , *GRAFT rejection , *MICRORNA , *BIOMARKERS - Published
- 2024
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9. Low back pain in German elite rowers.
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Felker, K., Fett, D., and Platen, P.
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- 2015
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10. Low back pain in German elite hockey players.
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Fett, D., Felker, K., and Platen, P.
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- 2015
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11. Production and decay of the heaviest odd-Z nuclei in the 249Bk + 48Ca reaction.
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Oganessian, Yu Ts, Abdullin, F. Sh, Alexander, C., Binder, J., Boll, R. A., Dmitriev, S. N., Ezold, J., Felker, K., Gostic, J. M., Grzywacz, R. K., Hamilton, J. H., Henderson, R. A., Itkis, M. G., Miernik, K., Miller, D., Moody, K. J., Polyakov, A. N., Ramayya, A. V., Roberto, J. B., and Ryabinin, M. A.
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- 2015
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12. Improved cache performance in Monte Carlo transport calculations using energy banding.
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Siegel, A., Smith, K., Felker, K., Romano, P., Forget, B., and Beckman, P.
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CACHE memory , *MONTE Carlo method , *NUMERICAL calculations , *ENERGY bands , *COMPUTER algorithms , *PARTICLES , *MACHINE theory - Abstract
Abstract: We present an energy banding algorithm for Monte Carlo (MC) neutral particle transport simulations which depend on large cross section lookup tables. In MC codes, read-only cross section data tables are accessed frequently, exhibit poor locality, and are typically too much large to fit in fast memory. Thus, performance is often limited by long latencies to RAM, or by off-node communication latencies when the data footprint is very large and must be decomposed on a distributed memory machine. The proposed energy banding algorithm allows maximal temporal reuse of data in band sizes that can flexibly accommodate different architectural features. The energy banding algorithm is general and has a number of benefits compared to the traditional approach. In the present analysis we explore its potential to achieve improvements in time-to-solution on modern cache-based architectures. [Copyright &y& Elsevier]
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- 2014
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13. Multi-core performance studies of a Monte Carlo neutron transport code
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Felker, K.
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- 2013
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14. Experimental studies of the 249Bk + 48Ca reaction including decay properties and excitation function for isotopes of element 117, and discovery of the new isotope 277Mt.
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Oganessian, Yu. Ts., Abdullin, F. Sh., Alexander, C., Binder, J., Boll, R. A., Dmitriev, S. N., Ezold, J., Felker, K., Gostic, J. M., Grzywacz, R. K., Hamilton, J. H., Henderson, R. A., Itkis, M. G., Miernik, K., Miller, D., Moody, K. J., Polyakov, A. N., Ramayya, A. V., Roberto, J. B., and Ryabinin, M. A.
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NUCLEAR excitation , *CALCIUM isotopes , *BERKELIUM , *SUPERHEAVY elements , *NUCLEAR reactions , *NUCLEAR cross sections , *RADIOACTIVE decay - Abstract
Studies of superheavy nuclei produced in the 249Bk + 48Ca reaction were performed using the Dubna Gas Filled Recoil Separator. The cross section for the production of 293117 and 294117 isotopes was measured at five excitation energies of the 297117 compound nucleus ranging from 30 to 48 MeV and yielding maximum values of 1.1-0.6+1.2 pb for the 3n and 2.4-1.4+3.3pb for the 4n reaction channels. Alpha emission from 281Rg competing with spontaneous fission (ɑ/SF decay probability 1:9) was observed for the first time leading to the identification of the new isotope 277Mt (TSF ~ 5 ms). The measured decay properties are in good agreement with those expected based on the properties of neighboring even-Z and odd-Z nuclei. The ɑ energies and half-lives of odd-Z isotopes observed in the 293117 and 294117 decay chains together with results obtained for lower-Z superheavy nuclei demonstrate enhanced stability with increasing neutron number toward the predicted new magic number N = 184. [ABSTRACT FROM AUTHOR]
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- 2013
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15. Production and Decay of the Heaviest Nuclei 293, 294117 and 294118.
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Oganessian, Yu.Ts., Abdullin, F. Sh., Alexander, C., Binder, J., Boll, R. A., Dmitriev, S. N., Ezold, J., Felker, K., Gostic, J. M., Grzywacz, R. K., Hamilton, J. H., Henderson, R. A., Itkis, M. G., Miernik, K., Miller, D., Moody, K. J., Polyakov, A. N., Ramayya, A. V., Roberto, J. B., and Ryabinin, M. A.
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RADIOACTIVE decay , *HEAVY nuclei , *RADIOISOTOPES , *PARTICLES (Nuclear physics) , *NUCLEAR reactions , *CYCLOTRONS - Abstract
Two years after the discovery of element 117, we undertook a second campaign using the 249Bk + 48Ca reaction for further investigations of the production and decay properties of the isotopes of element 117 on a larger number of events. The experiments were started in the end of April 2012 and are still under way. This Letter presents the results obtained in 1200 hours of an experimental run with the beam dose of 48Ca of about 1.5 X 1019 particles. The 249Bk target was irradiated at two energies of 48Ca that correspond to the maximum probability of the reaction channels with evaporation of three and four neutrons from the excited 297117. In this experiment, two decay chains of 294117 (3M) and five decay chains of 293117 (4M) were detected. In the course of the long-term work, 249Cf--the product of decay of 249Bk (330 d)--is being accumulated in the target. Consequently, in the present experiment, we also detected a single decay of the known isotope 294118 that was produced during 2002-2005 in the reaction 249Cf(48Ca, 3M)294118. The obtained results are compared with the data from previous experiments. The experiments are carried out in the Flerov Laboratory of Nuclear Reactions, Joint Institute for Nuclear Research, using the heavy-ion cyclotron U400. [ABSTRACT FROM AUTHOR]
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- 2012
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16. Abnormal Global Longitudinal Strain During Anthracycline Treatment Predicts Future Cardiotoxicity in Children.
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Gunsaulus M, Alsaied T, Tersak JM, Friehling E, and Rose-Felker K
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- Humans, Female, Male, Retrospective Studies, Child, Adolescent, Stroke Volume drug effects, Child, Preschool, Antibiotics, Antineoplastic adverse effects, Doxorubicin adverse effects, Ventricular Dysfunction, Left chemically induced, Ventricular Function, Left drug effects, Cancer Survivors, Global Longitudinal Strain, Cardiotoxicity etiology, Echocardiography, Anthracyclines adverse effects, Neoplasms drug therapy
- Abstract
Global longitudinal strain (GLS) is a sensitive predictor of cardiotoxicity in adults with cancer. However, the significance of abnormal GLS during childhood cancer treatment is less well-understood. The objective was to evaluate the use of GLS for predicting later cardiac dysfunction in pediatric cancer survivors exposed to high-dose anthracyclines. This was a retrospective study of pediatric patients exposed to a doxorubicin isotoxic equivalent dose of ≥ 225 mg/m
2 . Transthoracic echocardiograms (TTE) were obtained prior to chemotherapy (T1), during anthracycline therapy (T2), and following completion of therapy (T3). Cardiotoxicity was defined as meeting at least one of the following criteria after anthracycline therapy: a decrease in left ventricle ejection fraction (LVEF) by 10% from baseline to a value < 55%, fractional shortening < 28%, or a decrease in GLS by ≥ 15% from baseline. Nineteen of 57 (33%) patients met criteria for cardiotoxicity at T3. Cardiotoxicity was associated with a lower LVEF at T2 (p = 0.0003) and a decrease in GLS by ≥ 15% at T2 compared to baseline (p = < 0.0001). ROC analysis revealed that the best predictor of cardiotoxicity at T3 was the percent change in GLS at T2 compared to baseline (AUC 0.87). A subgroup analysis revealed that a decrease in GLS by ≥ 15% from baseline at 0-6 months from completion of anthracycline therapy was associated with cardiotoxicity > 1-year post-treatment (p = 0.017). A decline in GLS during chemotherapy was the best predictor of cardiotoxicity post-treatment. GLS serves as an important marker of cardiac function in pediatric patients undergoing treatment with anthracyclines., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)- Published
- 2024
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17. Cardiac MRI-Derived Inferior Vena Cava Cross-Sectional Area Correlates with Measures of Fontan-Associated Liver Disease.
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Gunsaulus M, Wang L, Haack L, Christopher A, Feingold B, Squires J, Horslen S, Hoskoppal A, Rose-Felker K, West S, Trucco S, Squires J, Olivieri L, Kreutzer J, Goldstein B, and Alsaied T
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- Child, Humans, Vena Cava, Inferior diagnostic imaging, Liver Cirrhosis diagnostic imaging, Magnetic Resonance Imaging, Ultrasonography, Liver Diseases diagnostic imaging, Liver Diseases etiology, Fontan Procedure adverse effects
- Abstract
There is currently no clear consensus on screening techniques to evaluate the presence or severity of Fontan-associated liver disease (FALD). Cardiac MRI (CMR) is used routinely for post-Fontan surveillance, but CMR-derived measures that relate to the severity of FALD are not yet defined. This was a cross-sectional single-center study of post-Fontan patients who underwent a CMR. CMR exams were re-analyzed by a single pediatric cardiologist. Surrogates of FALD included Gamma-Glutamyl Transferase (GGT), Fibrosis-4 laboratory score (FIB-4), and imaging findings. Findings consistent with cirrhosis on liver ultrasound included increased liver echogenicity and/or nodularity. Statistical analyses were performed to investigate potential relationships between CMR parameters and markers of FALD. Sixty-one patients were included. A larger inferior vena cava cross-sectional area (IVC-CSA) indexed to height was significantly associated with a higher FIB-4 score (Spearman's ρ = 0.28, p = 0.04), a higher GGT level (Spearman's ρ = 0.40, p = 0.02), and findings consistent with cirrhosis on liver ultrasound (OR 1.17, 95% CI: (1.01, 1.35), p = 0.04). None of the other CMR parameters were associated with markers of FALD. A larger indexed IVC-CSA was associated with higher systemic ventricle end-diastolic pressure (EDP) on cardiac catheterization (Spearman's ρ = 0.39, p = 0.018) as well as older age (Spearman's ρ = 0.46, p = < 0.001). Indexed IVC-CSA was the only CMR parameter that was associated with markers of FALD. This measure has the potential to serve as an additional non-invasive tool to improve screening strategies for FALD., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)
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- 2024
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18. Assessing Donor-Recipient Size Mismatch in Pediatric Heart Transplantation: Lessons Learned From Over 7,500 Transplants.
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Amdani S, Aljohani OA, Kirklin JK, Cantor R, Koehl D, Schumacher K, Nandi D, Khoury M, Dreyer W, Rose-Felker K, Nasman C, and Kemna MS
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- Humans, Child, Retrospective Studies, Tissue Donors, Graft Survival, Tissue and Organ Procurement, Heart Failure, Heart Transplantation
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Background: To date, no studies have identified an optimal metric to match donor-recipient (D-R) pairs in pediatric heart transplantation (HT)., Objectives: This study sought to identify size mismatch metrics that predicted graft survival post-HT., Methods: D-R pairs undergoing HT in Pediatric Heart Transplant Society database from 1993 to 2021 were included. Effects of size mismatch by height, weight, body mass index, body surface area, predicted heart mass, and total cardiac volume (TCV) on 1- and 5-year graft survival and morbidity outcomes (rejection and cardiac allograft vasculopathy) were evaluated. Cox models with stepwise selection identified size metrics that independently predicted graft survival., Results: Of 7,715 D-R pairs, 36.0% were well matched (D-R ratio: -20% to +20%) by weight, 39.0% by predicted heart mass, 50.0% by body surface area, 57.0% by body mass index, 71.0% by height, and 93.0% by TCV. Of all size metrics, only D-R mismatch by height and TCV predicted graft survival at 1 and 5 years. Effects of D-R size mismatch on graft survival were nonlinear. At both 1 and 5 years post-HT, D-R undersizing and oversizing by height led to increased graft loss, with graft loss observed more frequently with undersizing. Moderately undersized donors by height (D-R ratio: <-30%) frequently experienced rejection post-HT (P < 0.001). Assessing D-R size matching by TCV, minimal donor undersizing was protective, while oversizing up to 25% was not associated with increased graft loss., Conclusions: In pediatric HT, D-R appear most optimally matched using TCV. Only D-R size mismatch by TCV and height independently predicts graft survival. Standardizing size matching across centers may reduce donor discard., Competing Interests: Funding Support and Author Disclosures Dr Amdani is a site principal investigator for a multicenter study led by the University of Michigan (reports no salary support). Dr Kirklin has received partial support as principle investigator of the INTERMACS National Heart, Lung, and Blood Institute–sponsored registry for U.S. mechanical circulatory support (funding paid through institution). All other authors have reported that they have no relationships relevant to the contents of this paper to disclose., (Copyright © 2024 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)
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- 2024
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19. Elimination of 15N-thymidine after oral administration in human infants.
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Ammanamanchi N, Yester J, Bargaje AP, Thomas D, Little KC, Janzef S, Francis K, Weinberg J, Johnson J, Seery T, Harris TH, Funari BJ, Rose-Felker K, Zinn M, Miller SA, West SC, Feingold B, Zhou H, Steinhauser ML, Csernica T, Michener R, and Kühn B
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- Humans, Nitrogen Isotopes, Administration, Oral, Mouth, Tetralogy of Fallot drug therapy, Heart Failure drug therapy
- Abstract
Background: We have developed a new clinical research approach for the quantification of cellular proliferation in human infants to address unanswered questions about tissue renewal and regeneration. The approach consists of oral 15N-thymidine administration to label cells in S-phase, followed by Multi-isotope Imaging Mass Spectrometry for detection of the incorporated label in cell nuclei. To establish the approach, we performed an observational study to examine uptake and elimination of 15N-thymidine. We compared at-home label administration with in-hospital administration in infants with tetralogy of Fallot, a form of congenital heart disease, and infants with heart failure., Methods: We examined urine samples from 18 infants who received 15N-thymidine (50 mg/kg body weight) by mouth for five consecutive days. We used Isotope Ratio Mass Spectrometry to determine enrichment of 15N relative to 14N (%) in urine., Results/findings: 15N-thymidine dose administration produced periodic rises of 15N enrichment in urine. Infants with tetralogy of Fallot had a 3.2-fold increase and infants with heart failure had a 4.3-fold increase in mean peak 15N enrichment over baseline. The mean 15N enrichment was not statistically different between the two patient populations (p = 0.103). The time to peak 15N enrichment in tetralogy of Fallot infants was 6.3 ± 1 hr and in infants with heart failure 7.5 ± 2 hr (mean ± SEM). The duration of significant 15N enrichment after a dose was 18.5 ± 1.7 hr in tetralogy of Fallot and in heart failure 18.2 ± 1.8 hr (mean ± SEM). The time to peak enrichment and duration of enrichment were also not statistically different (p = 0.617 and p = 0.887)., Conclusions: The presented results support two conclusions of significance for future applications: (1) Demonstration that 15N-thymidine label administration at home is equivalent to in-hospital administration. (2) Two different types of heart disease show no differences in 15N-thymidine absorption and elimination. This enables the comparative analysis of cellular proliferation between different types of heart disease., Competing Interests: The authors declare that they have no competing interests., (Copyright: © 2024 Ammanamanchi et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
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- 2024
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20. Short-term clinical outcomes and predicted cost savings of dd-cfDNA-led surveillance after pediatric heart transplantation.
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Feingold B, Rose-Felker K, West SC, Miller SA, and Zinn MD
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- Young Adult, Humans, Child, Adolescent, Cost Savings, Graft Rejection etiology, Graft Rejection genetics, Biopsy, Cell-Free Nucleic Acids, Heart Transplantation adverse effects
- Abstract
Background: Endomyocardial biopsy (EMB)-led surveillance is common after pediatric heart transplantation (HT), with some centers performing periodic surveillance EMBs indefinitely after HT. Donor derived cell-free DNA (dd-cfDNA)-led surveillance offers an alternative, but knowledge about its clinical and economic outcomes, both key drivers of potential utilization, are lacking., Methods: Using single-center recipient and center-level data, we describe clinical outcomes prior to and since transition from EMB-led surveillance to dd-cfDNA-led surveillance of pediatric and young adult HT recipients. These data were then used to inform Markov models to compare costs between EMB-led and dd-cfDNA-led surveillance strategies., Results: Over 34.5 months, dd-cfDNA-led surveillance decreased the number of EMBs by 81.8% (95% CI 76.3%-86.5%) among 120 HT recipients (median age 13.3 years). There were no differences in the incidences of graft loss or death among all recipients followed at our center prior to and following implementation of dd-cfDNA-led surveillance (graft loss: 2.9 vs. 1.5 per 100 patient-years; p = .17; mortality: 3.7 vs. 2.2 per 100 patient-years; p = .23). Over 20 years from HT, dd-cfDNA-led surveillance is projected to cost $8545 less than EMB-led surveillance. Model findings were robust in sensitivity and scenario analyses, with cost of EMB, cost of dd-cfDNA testing, and probability of elevated dd-cfDNA most influential on model findings., Conclusions: dd-cfDNA-led surveillance shows promise as a less invasive and cost saving alternative to EMB-led surveillance among pediatric and young adult HT recipients., (© 2023 The Authors. Clinical Transplantation published by John Wiley & Sons Ltd.)
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- 2023
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21. Acute-Onset Fever and Abdominal Pain Leading to Shock in a Healthy 13-year-old Girl.
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Bowen J, Rose-Felker K, and Aldewereld Z
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- Female, Humans, Adolescent, Abdominal Pain etiology, Fever etiology
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- 2023
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22. Responsiveness to second and third dose of mRNA COVID-19 vaccination in adolescent and young adult heart transplant recipients.
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Feingold B, Berman P, Moninger A, Huston A, Stinner B, West SC, Rose-Felker K, Zinn MD, Miller SA, and Michaels MG
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- Adolescent, Antibodies, Viral, COVID-19 Vaccines, Humans, RNA, Messenger, Transplant Recipients, Vaccination methods, Young Adult, COVID-19 prevention & control, Heart Transplantation
- Abstract
Background: Third-dose mRNA COVID-19 vaccine is currently recommended in the United States for SOT recipients based in part on data showing diminished immune response, including Ab production, after a two-dose regimen. Data on vaccine response in adolescent and young adult SOT recipients are limited, including no data reported on third-dose responsiveness., Methods: Results of serologic testing in a convenience sample of 28 vaccinated adolescent and young adult HT recipients at a single institution were collected from the medical record and summarized., Results: At a median of 98.5 days (IQR 59-150) after second dose, 17 (61%) had an Ab response. Among 12 who had serology before and after third-dose vaccination, four of seven who were negative prior to third dose became positive at a median of 34 days (IQR 31-39.5) following third dose. No myocarditis, acute rejection, graft dysfunction, graft loss, or deaths were observed., Conclusions: These findings support recommendations for the routine administration of three doses of mRNA vaccines in adolescent and young adult HT recipients and show a potential subpopulation in whom the fourth dose should be contemplated., (© 2022 Wiley Periodicals LLC.)
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- 2022
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23. Early findings after integration of donor-derived cell-free DNA into clinical care following pediatric heart transplantation.
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Feingold B, Rose-Felker K, West SC, Zinn MD, Berman P, Moninger A, Huston A, Stinner B, Xu Q, Zeevi A, and Miller SA
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- Adolescent, Biomarkers blood, Biopsy, Child, Child, Preschool, Female, Follow-Up Studies, Graft Rejection blood, Graft Rejection pathology, Humans, Infant, Male, Myocardium pathology, Tissue Donors, Cell-Free Nucleic Acids blood, Graft Rejection diagnosis, Heart Transplantation
- Abstract
Background: Endomyocardial biopsy (EMB) is costly and discomforting yet remains a key component of surveillance after pediatric heart transplantation (HT). Donor-derived cell-free DNA (dd-cfDNA) has been histologically validated with high negative predictive value, offering an alternative to surveillance EMB (sEMB)., Methods: We implemented an alternative surveillance protocol using commercially available dd-cfDNA assays in place of sEMB after pediatric HT. Recipients ≧7 months post-HT with reassuring clinical assessment were referred for dd-cfDNA. When not elevated above the manufacturers' threshold, sEMB was deferred. Subsequent clinical status and results of follow-up EMB were analyzed., Results: Over 17 months, 58 recipients [34% female, median age at HT 3.1 years (IQR 0.6-10.6)] had dd-cfDNA assessed per protocol. Median age was 14.8 years (8.4-18.3) and time from HT 6.0 years (2.2-11.2). Forty-seven (81%) had non-elevated dd-cfDNA and 11 (19%) were elevated. During a median of 8.7 months (4.2-15), all are alive without allograft loss/new dysfunction. Among those with non-elevated dd-cfDNA, 24 (51%) had subsequent sEMB at 12.1 months (6.9-12.9) with 23 showing no acute rejection (AR): grade 0R/pAMR0 (n = 16); 1R(1A)/pAMR0 (n = 7). One had AR (grade 2R(3A)/pAMR0) on follow-up sEMB after decreased immunosuppression following a diagnosis of PTLD. All 11 with elevated dd-cfDNA had reflex EMB at 19 days (12-32) with AR in 4: grade 1R(1B-2)/pAMR0 (n = 3); 1R(1B)/pAMR2 (n = 1)., Conclusions: dd-cfDNA assessment in place of selected, per-protocol EMB decreased surveillance EMB by 81% in our pediatric HT recipient cohort with no short-term adverse outcomes. Individual center approach to surveillance EMB will influence the utility of these findings., (© 2021 Wiley Periodicals LLC.)
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- 2022
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24. Impact of the 2016 revision of US Pediatric Heart Allocation Policy on waitlist characteristics and outcomes.
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Magnetta DA, Godown J, West S, Zinn M, Rose-Felker K, Miller S, and Feingold B
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- Child, Child, Preschool, Female, Follow-Up Studies, Heart Defects, Congenital surgery, Humans, Infant, Infant, Newborn, Male, Prognosis, Resource Allocation statistics & numerical data, Survival Rate, Heart Defects, Congenital mortality, Heart Transplantation mortality, Resource Allocation legislation & jurisprudence, Tissue and Organ Procurement statistics & numerical data, Waiting Lists mortality
- Abstract
US Pediatric Heart Allocation Policy was recently revised, deprioritizing candidates with cardiomyopathy while maintaining status 1A eligibility for congenital heart disease (CHD) candidates on "high-dose" inotropes. We compared waitlist characteristics and mortality around this change. Status 1A listings decreased (70% to 56%, P < .001) and CHD representation increased among status 1A listings (48% vs 64%, P < .001). Waitlist mortality overall (subdistribution hazard ratio [SHR] 0.96, P = .63) and among status 1A candidates (SHR 1.16, P = .14) were unchanged. CHD waitlist mortality trended better (SHR 0.82, P = .06) but was unchanged for CHD candidates listed status 1A (SHR 0.92, P = .47). Status 1A listing exceptions increased 2- to 3-fold among hypertrophic and restrictive cardiomyopathy candidates and 13.5-fold among dilated cardiomyopathy (DCM) candidates. Hypertrophic (SHR 6.25, P = .004) and restrictive (SHR 3.87, P = .03) cardiomyopathy candidates without status 1A exception had increased waitlist mortality, but those with DCM did not (SHR 1.26, P = .32). Ventricular assist device (VAD) use increased only among DCM candidates ≥1 years old (26% vs 38%, P < .001). Current allocation policy has increased CHD status 1A representation but has not improved their waitlist mortality. Excessive DCM status 1A listing exceptions and continued status 1A prioritization of children on stable VADs potentially diminish the intended benefits of policy revision., (© 2019 The American Society of Transplantation and the American Society of Transplant Surgeons.)
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- 2019
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25. Improving paediatric cardiologists' awareness about the needs of childhood cancer survivors: results of a single-centre directed educational initiative.
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Rose-Felker K, Effinger K, Kelleman MS, Sachdeva R, Meacham LR, and Border WL
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- Antineoplastic Agents therapeutic use, Cardiologists education, Cardiovascular Diseases chemically induced, Cardiovascular Diseases epidemiology, Child, Follow-Up Studies, Humans, Incidence, Neoplasms epidemiology, Retrospective Studies, Risk Factors, Survival Rate trends, Time Factors, United States epidemiology, Antineoplastic Agents adverse effects, Attitude of Health Personnel, Cancer Survivors, Cardiologists standards, Cardiovascular Diseases psychology, Health Knowledge, Attitudes, Practice, Neoplasms drug therapy
- Abstract
Background: Cardiovascular disease is a leading cause of morbidity and mortality in childhood cancer survivors. Cardiologists must be aware of risk factors and long-term follow-up guidelines, which have historically been the purview of oncologists. Little is known about paediatric cardiologists' knowledge regarding the cardiotoxicity of cancer treatment and how to improve this knowledge., Methods: A total of 58 paediatric cardiologists anonymously completed a 21-question, web-based survey focused on four cardio-oncology themes: cancer treatment-related risk factors (n = 6), patient-related risk factors (n = 6), recommended surveillance (n = 3), and cardiac-specific considerations (n = 6). Following the baseline survey, a multi-disciplinary team of paediatric cardiologists and cancer survivor providers developed an in-person and web-based educational intervention. A post-intervention survey was conducted 5 months later., Results: The response rate was 41/58 (70.7%) pre-intervention and 30/58 (51.7%) post-intervention. On the baseline survey, the percentage of correct answers was 68.8 ± 10.3%, which improved to 79.2 ± 16.2% after the intervention (p = 0.009). The theme with the most profound knowledge deficit was surveillance; however, it also had the greatest improvement after the intervention (49.6 ± 26.7 versus 66.7 ± 27.7% correct, p = 0.025). Individual questions with the largest per cent improvement pertained to risk of cardiac dysfunction with time since treatment (52.4 versus 93.1%, p = 0.002) and the role of dexrazoxane (48.8 versus 82.8%, p = 0.020)., Conclusion: Specific knowledge deficits about the care of paediatric cancer survivors were identified amongst cardiologists using a web-based survey. Knowledge of surveillance was initially lowest but improved the most after an educational intervention. This highlights the need for cardio-oncology-based educational initiatives among paediatric cardiologists.
- Published
- 2019
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26. Neutropenia in pediatric heart transplant recipients.
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Rose-Felker K, Mukhtar A, Kelleman MS, Deshpande SR, and Mahle WT
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- Adolescent, Child, Child, Preschool, Female, Follow-Up Studies, Graft Rejection epidemiology, Graft Rejection etiology, Graft Survival, Humans, Incidence, Infant, Infections epidemiology, Infections etiology, Male, Neutropenia epidemiology, Postoperative Complications, Prevalence, Retrospective Studies, Survival Analysis, Heart Transplantation mortality, Neutropenia etiology
- Abstract
Neutropenia has been reported in pediatric heart transplant recipients, but its association with infectious morbidity and mortality is unknown. We sought to determine neutropenia's prevalence and impact on infection, rejection, and survival. A retrospective analysis of pediatric heart transplant recipients from March 2005 to August 2015 was performed. Demographics, medications, infection, and rejection data were collected. Of 142 pediatric heart transplant recipients, 77 (54.2%) developed neutropenia within 4.7 months [3.3-12.1 months] of transplant. In all patients, the adjusted 5-year cumulative incidence of neutropenia was 30.2%. Fifty-one patients (66.2%) had recurrent neutropenia. Six of 14 tested had positive antineutrophil antibodies. Medications associated with neutropenia were decreased in 15 (19.5%) and discontinued in 42 (54.4%) patients with no change in 1-year rejection rates compared to published data. Fifteen patients developed infection within 30 days of neutropenia and two from 30 days to 1 year, with an infection rate similar to the non-neutropenic group. There was no significant difference in survival, ANC, rate of rejection or PTLD in neutropenic patients with and without infection at median follow-up (5.5 years). Neutropenia is common in pediatric heart transplant recipients. Neutropenia had <20% risk of associated infection, similar to non-neutropenic patients. Infection in neutropenic patients did not increase mortality., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)
- Published
- 2018
- Full Text
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27. Appropriateness of Outpatient Echocardiograms Ordered by Pediatric Cardiologists or Other Clinicians.
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Rose-Felker K, Kelleman MS, Campbell RM, and Sachdeva R
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- Adolescent, Ambulatory Care, Child, Humans, Cardiology, Echocardiography statistics & numerical data, Practice Patterns, Physicians'
- Abstract
Objective: To assess the appropriateness and diagnostic yield of TTEs ordered by various pediatric providers according to the pediatric appropriate use criteria (AUC) for outpatient transthoracic echocardiography (TTE) before its release., Study Design: Clinic notes of patients aged ≤18 years who underwent initial outpatient TTE between April and September 2014 were reviewed to determine the AUC indication, and appropriateness was assigned based on the AUC document. Ordering physicians were categorized into cardiologists, primary care physicians (PCPs; including pediatricians and family practitioners [FPs]), and noncardiology subspecialists., Results: Of the 1921 TTEs ordered during the study period, 84.6% were by cardiologists, 9.2% by pediatricians, 3.4% by FPs, and 2.8% by noncardiology subspecialists. The appropriateness rate for cardiologists was higher than that for PCPs (86% vs 64%; P < .001) but not noncardiology subspecialist (86% vs 87%; P = .80). PCPs had a significantly higher proportion of studies that could not be classified compared with cardiologists (35% vs 5%; P < .001) and noncardiology subspecialists (35% vs 11%; P < .001), owing primarily to a lack of adequate clinical information. The likelihood of an abnormal finding was higher in TTEs ordered by a cardiologist vs those ordered by a noncardiologist (OR, 4.8; 95% CI, 2.1-10.9; P < .001)., Conclusions: Compared with PCPs, cardiologists ordered more TTEs, had the highest yield of abnormal findings, and had greater appropriateness of TTE orders. A large proportion of TTEs ordered by PCPs were unclassifiable owing to insufficient information. This study lays a framework for provider education and improvement in the TTE order intake process., (Copyright © 2017 Elsevier Inc. All rights reserved.)
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- 2017
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28. Cardio-oncology Related to Heart Failure: Pediatric Considerations for Cardiac Dysfunction.
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Rose-Felker K, Border WL, Hong BJ, and Chow EJ
- Subjects
- Antineoplastic Agents therapeutic use, Child, Evidence-Based Medicine, Heart Failure chemically induced, Humans, Neoplasms complications, Neoplasms drug therapy, Survivors, Ventricular Function, Left drug effects, Antineoplastic Agents adverse effects, Heart Failure prevention & control, Neoplasms rehabilitation
- Abstract
Although tremendous advances in pediatric cancer treatment have improved the survival of many children, these patients remain at increased risk of early morbidity and mortality with cardiovascular disease as a leading cause of death. Heightened awareness in providers with increased surveillance and improvement in cardiovascular imaging modalities have led to earlier detection of cardiac dysfunction, but the outcomes remain poor once this has dysfunction developed. A great deal of work remains to be done to refine screening and identify high-risk patients more precisely, and to develop more evidence-based strategies for effective primary and secondary cardioprotection and treatment., (Copyright © 2016 Elsevier Inc. All rights reserved.)
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- 2017
- Full Text
- View/download PDF
29. Preoperative Use of CT Angiography in Infants With Coarctation of the Aorta.
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Rose-Felker K, Robinson JD, Backer CL, Rigsby CK, Eltayeb OM, Mongé MC, Rychlik K, Sammet CL, and Gossett JG
- Subjects
- Aortic Coarctation surgery, Echocardiography, Female, Humans, Imaging, Three-Dimensional, Infant, Male, Preoperative Period, Retrospective Studies, Aorta, Thoracic diagnostic imaging, Aortic Coarctation diagnosis, Computed Tomography Angiography methods, Vascular Surgical Procedures methods
- Abstract
Background: Computed tomographic angiography (CTA) and echocardiography (echo) are used preoperatively in coarctation of the aorta to define arch hypoplasia and great vessel branching. We sought to determine differences in quantitative measurements, as well as surgical utility, between modalities., Methods: Infants (less than six months) with both CTA and echo prior to coarctation repair from 2004 to 2013 were included. Measurements were compared and correlated with surgical approach. Three surgeons reviewed de-identified images to predict approach and characterize utility. Computed tomographic angiography radiation dose was calculated., Results: Thirty-three patients were included. No differences existed in arch measurements between echo and CTA ( z-score: -2.59 vs -2.43; P = .47). No differences between modalities were seen for thoracotomy ( z-score: -2.48 [echo] vs -2.31 [CTA]; P = .48) or sternotomy ( z-score: -3.13 [echo] vs -3.08 [CTA]; P = .84). Computed tomographic angiography delineated great vessel branching pattern in two patients with equivocal echo findings ( P = .60). Surgeons rated CTA as far more useful than echo in understanding arch hypoplasia and great vessel branching in cases where CTA was done to resolve anatomical questions that remain after echo evaluation. Two of three surgeons were more likely to choose the surgical approach taken based on CTA (surgeon A, P = .02; surgeon B, P = .01). Radiation dose averaged 2.5 (1.6) mSv and trended down from 2.9 mSv (1.8 mSv; n = 20) to 1.6 mSv (0.5 mSv; n = 7) ( P = .06) with new technology., Conclusion: Although CTA and echo measurements of the aorta do not differ, CTA better delineates branching and surgeons strongly prefer it for three-dimensional arch anatomy. We recommend CTA for patients with anomalous arch branching patterns, diffuse or complex hypoplasia, or unusual arch morphology not fully elucidated by echo.
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- 2017
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30. Appropriate Use and Clinical Impact of Echocardiographic "Evaluation of Murmur" in Pediatric Patients.
- Author
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Rose-Felker K, Kelleman MS, Campbell RM, Oster ME, and Sachdeva R
- Subjects
- Adolescent, Age Factors, Child, Child, Preschool, Clinical Competence, Heart Murmurs physiopathology, Humans, Infant, Medical Records, Predictive Value of Tests, Prognosis, Quality Indicators, Health Care, Referral and Consultation, Retrospective Studies, Echocardiography statistics & numerical data, Heart Murmurs diagnostic imaging, Patient Selection, Practice Patterns, Physicians', Unnecessary Procedures
- Abstract
Objective: To determine the appropriateness and yield of transthoracic echocardiograms (TTE) for murmur evaluation based on the pediatric Appropriate Use Criteria (AUC) and study the influence of patient age and physician experience on TTE appropriateness, yield, and ordering frequency., Design: Retrospective review of medical records of patients referred to our practice for murmur evaluation from April to September 2014. Data collected included indication for TTE, patient age, physician experience since fellowship, TTE findings and exit diagnosis. Appropriateness was assigned based on the AUC document., Setting: Pediatric cardiology clinics affiliated with a large pediatric cardiology practice., Patients: One thousand seven hundred one consecutive patients (≤ 18 years) referred to our practice for murmur evaluation., Interventions: Not applicable OUTCOME MEASURES: The primary outcome was appropriateness of TTE orders. The secondary outcomes were the yield of abnormal TTE findings and the influence of patient age and physician experience on appropriateness, yield, and frequency of ordering TTEs., Results: Of the 1701 patients referred for a murmur, 526 (30.9%) had a TTE [441/526 (83.8%) Appropriate; 85/526 (16.2%) Rarely Appropriate]. Abnormal findings were present in 130/441 rated Appropriate and none rated Rarely Appropriate. Infants <3 months had the highest rate of TTEs rated Appropriate and the highest yield of abnormal findings. Physicians with >20 years of experience not only had the lowest TTE ordering rate but also the lowest appropriateness rate with no difference in the yield of abnormal findings., Conclusions: Most TTEs ordered for murmur were for indications rated Appropriate. Abnormal findings were present in one-fourth and only those rated Appropriate. Patient age and physician experience can significantly influence TTE utilization. This information is helpful in designing quality initiatives to optimize TTE utilization for murmur evaluation., (© 2016 Wiley Periodicals, Inc.)
- Published
- 2016
- Full Text
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31. Production and decay of the heaviest nuclei (293,294)117 and (294)118.
- Author
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Oganessian YTs, Abdullin FSh, Alexander C, Binder J, Boll RA, Dmitriev SN, Ezold J, Felker K, Gostic JM, Grzywacz RK, Hamilton JH, Henderson RA, Itkis MG, Miernik K, Miller D, Moody KJ, Polyakov AN, Ramayya AV, Roberto JB, Ryabinin MA, Rykaczewski KP, Sagaidak RN, Shaughnessy DA, Shirokovsky IV, Shumeiko MV, Stoyer MA, Stoyer NJ, Subbotin VG, Sukhov AM, Tsyganov YS, Utyonkov VK, Voinov AA, and Vostokin GK
- Abstract
Two years after the discovery of element 117, we undertook a second campaign using the (249)Bk+(48)Ca reaction for further investigations of the production and decay properties of the isotopes of element 117 on a larger number of events. The experiments were started in the end of April 2012 and are still under way. This Letter presents the results obtained in 1200 hours of an experimental run with the beam dose of (48)Ca of about 1.5×10(19) particles. The (249)Bk target was irradiated at two energies of (48)Ca that correspond to the maximum probability of the reaction channels with evaporation of three and four neutrons from the excited (297)117. In this experiment, two decay chains of (294)117 (3n) and five decay chains of (293)117 (4n) were detected. In the course of the long-term work, (249)Cf-the product of decay of (249)Bk (330 d)-is being accumulated in the target. Consequently, in the present experiment, we also detected a single decay of the known isotope (294)118 that was produced during 2002-2005 in the reaction (249)Cf((48)Ca,3n)(294)118. The obtained results are compared with the data from previous experiments. The experiments are carried out in the Flerov Laboratory of Nuclear Reactions, Joint Institute for Nuclear Research, using the heavy-ion cyclotron U400.
- Published
- 2012
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32. Histological analysis of human meniscal allografts. A preliminary report.
- Author
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Rodeo SA, Seneviratne A, Suzuki K, Felker K, Wickiewicz TL, and Warren RF
- Subjects
- Adolescent, Adult, Antigens, CD analysis, Biopsy, Female, Follow-Up Studies, Humans, Immunohistochemistry, Male, Menisci, Tibial immunology, Middle Aged, Synovial Membrane cytology, Menisci, Tibial cytology, Menisci, Tibial transplantation
- Abstract
Background: Little is known about the biology of meniscal allograft transplantation in humans. In particular, little information is available about the phenotype of the cells that repopulate the allograft, whether an immune response is elicited against the graft, and whether the repopulating cells synthesize normal extracellular matrix components., Methods: A small biopsy specimen of the meniscal allograft (twenty-eight menisci in twenty-five patients) and the adjacent synovial membrane (sixteen patients) was harvested during follow-up arthroscopy in patients who had undergone meniscal allograft transplantation at a mean of sixteen months earlier. Seventeen patients had undergone concomitant reconstruction of the anterior cruciate ligament with an allograft. Normal menisci (unimplanted allografts) and synovial specimens from age-matched controls were examined as well. All twenty-eight meniscal allografts were examined histologically. Immunohistochemical analysis was carried out on ten menisci and nine synovial specimens with use of monoclonal antibodies to class-I and class-II major histocompatibility complex antigens, CD-8, CD-11b, and CD-19 epitopes, as well as other epitopes, to demonstrate immunogenic macromolecules, cytotoxic T-lymphocytes, activated macrophages, and B-lymphocytes., Results: Most of the specimens demonstrated incomplete repopulation with viable cells. The repopulating cells stained positively with phenotype markers for both synovial cells and fibroblasts. Polarized light microscopy demonstrated evidence of active remodeling of the matrix. The cells in frozen, unimplanted menisci stained positively for class-I and class-II human leukocyte antigens, indicating immunogenicity at the time of transplantation. Overall, nine of twelve specimens contained immunoreactive cells (B-lymphocytes or cytotoxic T-cells) in the meniscus or synovial tissue. However, only a small number of these cells was present. There was no evidence of frank immunological rejection. The clinical outcome (success or failure of the transplant) was not related to the overall histological score or to the presence of an immune response in the meniscal or synovial biopsy specimen., Conclusions: Human meniscal allograft transplants are repopulated with cells that appear to be derived from the synovial membrane; these cells appear to actively remodel the matrix. Although there is histological evidence of an immune response directed against the transplant, this response does not appear to affect the clinical outcome. The presence of histocompatibility antigens on the meniscal surface at the time of transplantation (even after freezing) indicates the potential for an immune response against the transplant., Clinical Relevance: Despite the absence of frank immunological rejection, a subtle immune reaction may affect the healing, incorporation, and revascularization of the graft. It is possible that the structural remodeling associated with cellular repopulation may render the meniscus more susceptible to injury.
- Published
- 2000
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33. The relationship of gender and family environment to eating disorder risk in adolescents.
- Author
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Felker KR and Stivers C
- Subjects
- Adolescent, Environment, Female, Humans, Male, Regression Analysis, Risk Factors, Sampling Studies, Sex Factors, Surveys and Questionnaires, Anorexia Nervosa psychology, Bulimia psychology, Family psychology
- Abstract
Incidence and prevalence rates of both anorexia nervosa and bulimia among adolescents have steadily increased during the past decade. The purpose of this study was to examine the relationship of gender and family environment to the risk of developing anorexia nervosa or bulimia in adolescents. The Family Environment Scale (FES; Moos & Moos, 1981) and the Setting Conditions for Anorexia Nervosa Scale (SCANS; Slade, Phil, & Dewey, 1986) were used to measure select components of family environment and risk of developing anorexia nervosa or bulimia, respectively. Data were collected from 393 students attending a private secondary boarding school located in central New Jersey. Subjects represented 35 states and 25 countries, had a mean age of 16.3 years, were predominantly Caucasian (75.6%) with a Catholic (27.5%) or Protestant (26.5%) affiliation, and reported a family income in excess of $50,000 (63.9%). Multiple regression using a unique approach revealed a significant relationship between family environment and the risk of developing anorexia nervosa or bulimia in adolescents (p < .01). The FES subscale of expressiveness was the only subscale found to have a significant relationship with the risk of developing anorexia nervosa or bulimia. Female subjects displayed a greater risk than did males (p < .01). Finally, no significant interaction was found between family environment and gender on the risk of developing anorexia nervosa or bulimia in adolescents. Simple correlation of the FES subscales was conducted by means of Pearson product moment and results indicated that lower cohesion, expressiveness, and organization were significantly associated with greater eating disorder risk (p < .01). Lower independence was significantly associated with increased eating disorder risk, but to a lesser degree (p < .05). Greater conflict (p < .01) and control (p < .05) were significantly associated with greater eating disorder risk.
- Published
- 1994
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