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Abstract
Syndromic CLN3-Batten is a fatal, pediatric, neurodegenerative disease caused by variants in CLN3, which encodes the endolysosomal transmembrane CLN3 protein. No approved treatment for CLN3 is currently available. The protracted and asynchronous disease presentation complicates the evaluation of potential therapies using clinical disease progression parameters. Biomarkers as surrogates to measure the progression and effect of potential therapeutics are needed. We performed proteomic discovery studies using cerebrospinal fluid (CSF) samples from 28 CLN3-affected and 32 age-similar non-CLN3 individuals. Proximal extension assay (PEA) of 1467 proteins and untargeted data-dependent mass spectrometry [MS; MassIVE FTP server (ftp://MSV000090147@massive.ucsd.edu)] were used to generate orthogonal lists of protein marker candidates. At an adjusted p-value of <0.1 and threshold CLN3/non-CLN3 fold-change ratio of 1.5, PEA identified 54 and MS identified 233 candidate biomarkers. Some of these (NEFL, CHIT1) have been previously linked with other neurologic conditions. Others (CLPS, FAM217B, QRICH2, KRT16, ZNF333) appear to be novel. Both methods identified 25 candidate biomarkers, including CHIT1, NELL1, and ISLR2 which had absolute fold-change ratios >2. NELL1 and ISLR2 regulate axonal development in neurons and are intriguing new candidates for further investigation in CLN3. In addition to identifying candidate proteins for CLN3 research, this study provides a comparison of two large-scale proteomic discovery methods in CSF.
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Affiliation(s)
- An N Dang Do
- Unit on Cellular Stress in Development and Diseases, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - David E Sleat
- Center for Advanced Biotechnology and Medicine, Rutgers Biomedical Health Sciences, Piscataway, New Jersey 08854, United States
- Department of Biochemistry and Molecular Biology, Robert-Wood Johnson Medical School, Rutgers Biomedical Health Sciences, Piscataway, New Jersey 08854, United States
| | - Kiersten Campbell
- Bioinformatics and Scientific Programming Core, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Nicholas L Johnson
- Bioinformatics and Scientific Programming Core, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Haiyan Zheng
- Center for Advanced Biotechnology and Medicine, Rutgers Biomedical Health Sciences, Piscataway, New Jersey 08854, United States
| | - Christopher A Wassif
- Section on Molecular Dysmorphology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Ryan K Dale
- Bioinformatics and Scientific Programming Core, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Forbes D Porter
- Section on Molecular Dysmorphology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, United States
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2
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Dang Do AN, Baker EH, Farmer CA, Soldatos AG, Thurm AE, Porter FD. Brain proton MR spectroscopy measurements in CLN3 disease. Mol Genet Metab 2023; 139:107584. [PMID: 37086568 PMCID: PMC10202445 DOI: 10.1016/j.ymgme.2023.107584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 02/22/2023] [Accepted: 04/14/2023] [Indexed: 04/24/2023]
Abstract
BACKGROUND CLN3 is an autosomal recessive lysosomal disorder with intracellular accumulation of ceroid-lipofuscins. CLN3 classically has onset around 4-6 years of age involving vision loss, followed by developmental regression and seizures. Symptoms are progressive and result in premature death. Because treatments are under development, here we explore magnetic resonance spectroscopy (MRS) measurements of metabolite levels in the brain as a potential objective outcome measures. METHODS Individuals with genetically confirmed CLN3 were enrolled from October 2017-November 2021 in a prospective natural history study (NCT033007304). Baseline concentrations of brain metabolites measured by MRS were compared to concurrently collected dimensional assessment measures: Vineland-3 Adaptive Behavior Composite (ABC) score, verbal intelligence quotient (VIQ), and the Physical, Capability with actual vision, and Clinical global impression of change sub-domains of the Unified Batten Disease Rating Scale (UBDRS). RESULTS 27 participants with typical CLN3 presentation (15F:12M; ages 6.0-20.7 years) completed MRS, ABC, and UBDRS; 20 (12F:8M; ages 6.5-20.7 years) also completed the VIQ assessment. N-acetyl aspartate [B(95% CI) = -0.61(-0.78;-0.45)] and glutamine/glutamate/GABA [B(95% CI) = -0.82(-1.04;-0.6)] in the parietal gray matter (PGM) decreased across the ages. The strongest correlations between MRS metabolite measurements and the clinical severity assessments were found with N-acetyl aspartate [VIQ (ρ = 0.58), Vineland-3 ABC (ρ = 0.59), UBDRS |ρ| range = (0.57;0.7)] and glutamine/glutamate/GABA [VIQ (ρ = 0.57), Vineland-3 ABC (ρ = 0.60), UBDRS |ρ| range = (0.59;0.77)] measured in the midline PGM. These correlations were accounted for when age was considered. CONCLUSIONS Based on their correlations to established assessments, NAA and glutamine/glutamate/GABA measured in the midline parietal gray matter may be useful indicators of CLN3 disease state. In a clinical trial, divergence of the MRS measurements and clinical severity markers from age may be useful as surrogate measures for treatment responses.
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Affiliation(s)
- An N Dang Do
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Bethesda, MD, USA.
| | - Eva H Baker
- Radiology and Imaging Sciences Department, Clinical Center, NIH, Bethesda, MD, USA
| | | | - Ariane G Soldatos
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, MD, USA
| | - Audrey E Thurm
- National Institute of Mental Health, NIH, Bethesda, MD, USA
| | - Forbes D Porter
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Bethesda, MD, USA
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Dang Do AN, Chang IJ, Jiang X, Wolfe LA, Ng BG, Lam C, Schnur RE, Allis K, Hansikova H, Ondruskova N, O’Connor SD, Sanchez-Valle A, Vollo A, Wang RY, Wolfenson Z, Perreault J, Ory DS, Freeze HH, Merritt JL, Porter FD. Elevated oxysterol and N-palmitoyl-O-phosphocholineserine levels in congenital disorders of glycosylation. J Inherit Metab Dis 2023; 46:326-334. [PMID: 36719165 PMCID: PMC10023375 DOI: 10.1002/jimd.12595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 01/19/2023] [Accepted: 01/23/2023] [Indexed: 02/01/2023]
Abstract
Congenital disorders of glycosylation (CDG) and Niemann-Pick type C (NPC) disease are inborn errors of metabolism that can both present with infantile-onset severe liver disease and other multisystemic manifestations. Plasma bile acid and N-palmitoyl-O-phosphocholineserine (PPCS) are screening biomarkers with proposed improved sensitivity and specificity for NPC. We report an infant with ATP6AP1-CDG who presented with cholestatic liver failure and elevated plasma oxysterols and bile acid, mimicking NPC clinically and biochemically. On further investigation, PPCS, but not the bile acid derivative N-(3β,5α,6β-trihydroxy-cholan-24-oyl) glycine (TCG), were elevated in plasma samples from individuals with ATP6AP1-, ALG1-, ALG8-, and PMM2-CDG. These findings highlight the importance of keeping CDG within the diagnostic differential when evaluating children with early onset severe liver disease and elevated bile acid or PPCS to prevent delayed diagnosis and treatment.
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Affiliation(s)
- An N. Dang Do
- Office of the Clinical Director, NICHD, NIH, Bethesda, MD, USA
- Correspondence An Ngoc Dang Do, MD PhD, , 10 Center Drive, MSC 1103, Bethesda, MD 20892
| | - Irene J. Chang
- Division of Genetic Medicine, Department of Pediatrics, University of Washington, Seattle, WA, USA
| | - Xutian Jiang
- Department of Medicine, Washington University School of Medicine, Saint Louis, MO, USA
| | - Lynne A. Wolfe
- Undiagnosed Diseases Program, Common Fund, National Institutes of Health, Bethesda, MD, USA
| | - Bobby G. Ng
- Human Genetics Program, Sanford Children’s Health Research Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, USA
| | - Christina Lam
- Division of Genetic Medicine, Department of Pediatrics, University of Washington, Seattle, WA, USA
- Center for Integrative Brain Research, Seattle Children’s Research Institute, Seattle, WA, USA
| | | | | | - Hana Hansikova
- Department of Pediatrics and Inherited Metabolic Disorders, Charles University and General University Hospital in Prague, Prague, Czech Republic
| | - Nina Ondruskova
- Department of Pediatrics and Inherited Metabolic Disorders, Charles University and General University Hospital in Prague, Prague, Czech Republic
| | - Shawn D. O’Connor
- Department of Pediatrics, Washington University School of Medicine in St. Louis, Saint Louis, MO, USA
| | | | - Arve Vollo
- Department of Paediatrics, Sykehuset Ostfold HF, Fredrikstad, Norway
| | - Raymond Y. Wang
- Children’s Hospital of Orange County, Orange County, CA, USA
- University of California-Irvine School of Medicine, Irvine, CA, USA
| | - Zoe Wolfenson
- Undiagnosed Diseases Program, Common Fund, National Institutes of Health, Bethesda, MD, USA
| | - John Perreault
- Office of the Clinical Director, NICHD, NIH, Bethesda, MD, USA
| | - Daniel S. Ory
- Department of Medicine, Washington University School of Medicine, Saint Louis, MO, USA
| | - Hudson H. Freeze
- Human Genetics Program, Sanford Children’s Health Research Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, USA
| | - J Lawrence Merritt
- Division of Genetic Medicine, Department of Pediatrics, University of Washington, Seattle, WA, USA
| | - Forbes D. Porter
- Section on Molecular Dysmorphology, NICHD, NIH, Bethesda, MD, USA
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Laqtom NN, Dong W, Medoh UN, Cangelosi AL, Dharamdasani V, Chan SH, Kunchok T, Lewis CA, Heinze I, Tang R, Grimm C, Dang Do AN, Porter FD, Ori A, Sabatini DM, Abu-Remaileh M. CLN3 is required for the clearance of glycerophosphodiesters from lysosomes. Nature 2022; 609:1005-1011. [PMID: 36131016 PMCID: PMC10510443 DOI: 10.1038/s41586-022-05221-y] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Accepted: 08/10/2022] [Indexed: 11/09/2022]
Abstract
Lysosomes have many roles, including degrading macromolecules and signalling to the nucleus1. Lysosomal dysfunction occurs in various human conditions, such as common neurodegenerative diseases and monogenic lysosomal storage disorders (LSDs)2-4. For most LSDs, the causal genes have been identified but, in some, the function of the implicated gene is unknown, in part because lysosomes occupy a small fraction of the cellular volume so that changes in lysosomal contents are difficult to detect. Here we develop the LysoTag mouse for the tissue-specific isolation of intact lysosomes that are compatible with the multimodal profiling of their contents. We used the LysoTag mouse to study CLN3, a lysosomal transmembrane protein with an unknown function. In children, the loss of CLN3 causes juvenile neuronal ceroid lipofuscinosis (Batten disease), a lethal neurodegenerative LSD. Untargeted metabolite profiling of lysosomes from the brains of mice lacking CLN3 revealed a massive accumulation of glycerophosphodiesters (GPDs)-the end products of glycerophospholipid catabolism. GPDs also accumulate in the lysosomes of CLN3-deficient cultured cells and we show that CLN3 is required for their lysosomal egress. Loss of CLN3 also disrupts glycerophospholipid catabolism in the lysosome. Finally, we found elevated levels of glycerophosphoinositol in the cerebrospinal fluid of patients with Batten disease, suggesting the potential use of glycerophosphoinositol as a disease biomarker. Our results show that CLN3 is required for the lysosomal clearance of GPDs and reveal Batten disease as a neurodegenerative LSD with a defect in glycerophospholipid metabolism.
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Affiliation(s)
- Nouf N Laqtom
- Department of Chemical Engineering, Stanford University, Stanford, CA, USA
- Department of Genetics, Stanford University, Stanford, CA, USA
- The Institute for Chemistry, Engineering & Medicine for Human Health (ChEM-H), Stanford University, Stanford, CA, USA
| | - Wentao Dong
- Department of Chemical Engineering, Stanford University, Stanford, CA, USA
- Department of Genetics, Stanford University, Stanford, CA, USA
- The Institute for Chemistry, Engineering & Medicine for Human Health (ChEM-H), Stanford University, Stanford, CA, USA
| | - Uche N Medoh
- Department of Chemical Engineering, Stanford University, Stanford, CA, USA
- Department of Genetics, Stanford University, Stanford, CA, USA
- The Institute for Chemistry, Engineering & Medicine for Human Health (ChEM-H), Stanford University, Stanford, CA, USA
- Department of Biochemistry, Stanford University School of Medicine, Stanford, CA, USA
| | - Andrew L Cangelosi
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
- Koch Institute for Integrative Cancer Research, Cambridge, MA, USA
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
| | | | - Sze Ham Chan
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Tenzin Kunchok
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
| | | | - Ivonne Heinze
- Leibniz Institute on Aging-Fritz Lipmann Institute, Jena, Germany
| | - Rachel Tang
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-Universität, Munich, Germany
| | - Christian Grimm
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-Universität, Munich, Germany
| | - An N Dang Do
- Division of Translational Medicine, Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Bethesda, MD, USA
| | - Forbes D Porter
- Division of Translational Medicine, Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Bethesda, MD, USA
| | - Alessandro Ori
- Leibniz Institute on Aging-Fritz Lipmann Institute, Jena, Germany
| | | | - Monther Abu-Remaileh
- Department of Chemical Engineering, Stanford University, Stanford, CA, USA.
- Department of Genetics, Stanford University, Stanford, CA, USA.
- The Institute for Chemistry, Engineering & Medicine for Human Health (ChEM-H), Stanford University, Stanford, CA, USA.
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Brudvig JJ, Swier VJ, Johnson TB, Cain JC, Pratt M, Rechtzigel M, Leppert H, Dang Do AN, Porter FD, Weimer JM. Glycerophosphoinositol is Elevated in Blood Samples From CLN3Δex7-8 pigs, Cln3Δex7-8 Mice, and CLN3-Affected Individuals. Biomark Insights 2022; 17:11772719221107765. [PMID: 36212622 PMCID: PMC9535353 DOI: 10.1177/11772719221107765] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 06/01/2022] [Indexed: 11/23/2022] Open
Abstract
Introduction: CLN3 Batten disease is a rare pediatric neurodegenerative lysosomal disorder
caused by biallelic disease-associated variants in CLN3.
Despite decades of intense research, specific biofluid biomarkers of disease
status have not been reported, hindering clinical development of therapies.
Thus, we sought to determine whether individuals with CLN3 Batten disease
have elevated levels of specific metabolites in blood. Methods: We performed an exhaustive metabolomic screen using serum samples from a
novel minipig model of CLN3 Batten disease and validated findings in
CLN3 pig serum and CSF and Cln3 mouse
serum. We further validate biomarker candidates with a retrospective
analysis of plasma and CSF samples collected from participants in a natural
history study. Plasma samples were evaluated from 22 phenotyped individuals
with CLN3 disease, 15 heterozygous carriers, and 6 non-affected non-carriers
(NANC). Results: CLN3 pig serum samples from 4 ages exhibited large elevations in 4
glycerophosphodiester species: glycerophosphoinositol (GPI),
glycerophosphoethanolamine (GPE), glycerophosphocholine (GPC), and
glycerophosphoserine (GPS). GPI and GPE exhibited the largest elevations,
with similar elevations found in CLN3 pig CSF and
Cln3 mouse serum. In plasma samples from individuals
with CLN3 disease, glycerophosphoethanolamine and glycerophosphoinositol
were significantly elevated with glycerophosphoinositol exhibiting the
clearest separation (mean 0.1338 vs 0.04401 nmol/mL for non-affected
non-carriers). Glycerophosphoinositol demonstrated excellent sensitivity and
specificity as a biomarker, with a receiver operating characteristic area
under the curve of 0.9848 (P = .0003). Conclusions: GPE and GPI could have utility as biomarkers of CLN3 disease status. GPI, in
particular, shows consistent elevations across a diverse cohort of
individuals with CLN3. This raises the potential to use these biomarkers as
a blood-based diagnostic test or as an efficacy measure for
disease-modifying therapies.
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Affiliation(s)
- Jon J Brudvig
- Pediatrics & Rare Diseases, Sanford Research, Sioux Falls, SD, USA
- Pediatrics, University of South Dakota Sanford School of Medicine, Vermillion, SD, USA
- Discovery Science, Amicus Therapeutics, Philadelphia, PA, USA
| | - Vicki J Swier
- Pediatrics & Rare Diseases, Sanford Research, Sioux Falls, SD, USA
| | - Tyler B Johnson
- Pediatrics & Rare Diseases, Sanford Research, Sioux Falls, SD, USA
- Discovery Science, Amicus Therapeutics, Philadelphia, PA, USA
| | - Jacob C Cain
- Pediatrics & Rare Diseases, Sanford Research, Sioux Falls, SD, USA
- Discovery Science, Amicus Therapeutics, Philadelphia, PA, USA
| | - Melissa Pratt
- Pediatrics & Rare Diseases, Sanford Research, Sioux Falls, SD, USA
| | - Mitch Rechtzigel
- Pediatrics & Rare Diseases, Sanford Research, Sioux Falls, SD, USA
| | - Hannah Leppert
- Pediatrics & Rare Diseases, Sanford Research, Sioux Falls, SD, USA
| | - An N Dang Do
- Division of Translational Medicine, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD, USA
| | - Forbes D Porter
- Division of Translational Medicine, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD, USA
| | - Jill M Weimer
- Pediatrics & Rare Diseases, Sanford Research, Sioux Falls, SD, USA
- Pediatrics, University of South Dakota Sanford School of Medicine, Vermillion, SD, USA
- Discovery Science, Amicus Therapeutics, Philadelphia, PA, USA
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Ballenger KL, Tugarinov N, Talvacchio SK, Knue MM, Dang Do AN, Ahlman MA, Reynolds JC, Yanovski JA, Marini JC. Osteogenesis Imperfecta: The Impact of Genotype and Clinical Phenotype on Adiposity and Resting Energy Expenditure. J Clin Endocrinol Metab 2022; 107:67-76. [PMID: 34519823 PMCID: PMC8684495 DOI: 10.1210/clinem/dgab679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Indexed: 11/19/2022]
Abstract
CONTEXT Mutations in type I collagen or collagen-related proteins cause osteogenesis imperfecta (OI). Energy expenditure and body composition in OI could reflect reduced mobility or intrinsic defects in osteoblast differentiation increasing adipocyte development. OBJECTIVE This study compares adiposity and resting energy expenditure (REE) in OI and healthy controls (HC), for OI genotype- and Type-associated differences. METHODS We studied 90 participants, 30 with OI (11 COL1A1 Gly, 8 COL1A2 Gly, 4 COL1A1 non-Gly, 1 COL1A2 non-Gly, 6 non-COL; 8 Type III, 16 Type IV, 4 Type VI, 1 Type VII, 1 Type XIV) and 60 HC with sociodemographic characteristics/BMI/BMIz similar to the OI group. Participants underwent dual-energy x-ray absorptiometry to determine lean mass and fat mass percentage (FM%) and REE. FM% and REE were compared, adjusting for covariates, to examine the relationship of OI genotypes and phenotypic Types. RESULTS FM% did not differ significantly in all patients with OI vs HC (OI: 36.6% ± 1.9%; HC: 32.7% ± 1.2%; P = 0.088). FM% was, however, greater than HC for those with non-COL variants (P = 0.016). FM% did not differ from HC among OI Types (P values > 0.05).Overall, covariate-adjusted REE did not differ significantly between OI and HC (OI: 1376.5 ± 44.7 kcal/d; HC: 1377.0 ± 96 kcal/d; P = 0.345). However, those with non-COL variants (P = 0.016) and Type VI OI (P = 0.04) had significantly lower REE than HC. CONCLUSION Overall, patients with OI did not significantly differ in either extra-marrow adiposity or REE from BMI-similar HC. However, reduced REE among those with non-COL variants may contribute to greater adiposity.
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Affiliation(s)
- Kaitlin L Ballenger
- Section on Growth and Obesity, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD, USA
| | - Nicol Tugarinov
- Section on Growth and Obesity, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD, USA
| | - Sara K Talvacchio
- Office of the Clinical Director, Division of Intramural Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD, USA
| | - Marianne M Knue
- Office of the Clinical Director, Division of Intramural Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD, USA
| | - An N Dang Do
- Office of the Clinical Director, Division of Intramural Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD, USA
| | - Mark A Ahlman
- Radiology and Imaging Sciences, Clinical Research Center, National Institutes of Health, Bethesda, MD, USA
| | - James C Reynolds
- Radiology and Imaging Sciences, Clinical Research Center, National Institutes of Health, Bethesda, MD, USA
| | - Jack A Yanovski
- Section on Growth and Obesity, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD, USA
| | - Joan C Marini
- Section on Heritable Disorders of Bone and Extracellular Matrix, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD, USA
- Correspondence: Joan C. Marini, MD, PhD, Head, Section on Heritable Disorders of Bone and Extracellular Matrix, NICHD, Bldg. 49, Rm. 5A52, 9000 Rockville Pike, Bethesda, MD, 20892, USA.
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Dang Do AN, Thurm AE, Farmer CA, Soldatos AG, Chlebowski CE, O'Reilly JK, Porter FD. Use of the Vineland-3, a measure of adaptive functioning, in CLN3. Am J Med Genet A 2021; 188:1056-1064. [PMID: 34913584 DOI: 10.1002/ajmg.a.62607] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 11/19/2021] [Accepted: 11/30/2021] [Indexed: 11/10/2022]
Abstract
Progressive vision loss and neurocognitive impairment are early and frequent presentations in CLN3 disease. This highlights neurodevelopmental functioning as critical to the disease, but limits the neuropsychological test repertoire. We evaluated the convergent validity of the Vineland Adaptive Behavior Scales as a potential outcome measure. In a prospective observational study of 22 individuals (female:male 11:11; 6-20 years-old) with a molecular diagnosis of CLN3, we used generalized linear models and Spearman correlations to quantify the relationship of the adaptive behavior composite (ABC) standard score with established outcomes of verbal IQ (VIQ) and disease severity (Unified Batten Disease Rating Scale, UBDRS) scores. We analyzed ABC changes in 1-year follow-up data in a subset of the same cohort (n = 17). The ABC and VIQ, both standard scores, exhibited a strong positive correlation in cross-sectional data (r = 0.81). ABC and UBDRS scores were strongly and positively correlated in cross-sectional data (rrange = 0.87-0.93). Participants' ABC scores decreased slightly over the 1-year follow-up period (mean change, 95% CI: -5.23, -2.16). The convergent validity of the Vineland-3 for use in CLN3 is supported by its relationships with the established outcomes of VIQ and UBDRS. Future longitudinal research, including replication in other cohorts and evaluation of sensitivity to change, will be important to establish utility of the Vineland-3 for monitoring change in CLN3.
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Affiliation(s)
- An N Dang Do
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Bethesda, Maryland, USA
| | - Audrey E Thurm
- National Institute of Mental Health, NIH, Bethesda, Maryland, USA
| | - Cristan A Farmer
- National Institute of Mental Health, NIH, Bethesda, Maryland, USA
| | - Ariane G Soldatos
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, USA
| | | | - Julie K O'Reilly
- National Institute of Mental Health, NIH, Bethesda, Maryland, USA
| | - Forbes D Porter
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Bethesda, Maryland, USA
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Franzone JM, Sargent BM, Dang Do AN, Knue M, Marini JC, Kruse RW. Stress Shielding in the Setting of Osteogenesis Imperfecta and the Effect of Downsizing an Intramedullary Rod: A Case Report. JBJS Case Connect 2021; 11:01709767-202109000-00042. [PMID: 34297706 DOI: 10.2106/jbjs.cc.20.00680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
CASE Cortical atrophy, or stress shielding, secondary to a large-diameter femoral intramedullary rod was noted over almost a decade in a now 14-year-old girl with osteogenesis imperfecta (OI). After an initial minimally invasive unsuccessful revision, we downsized the left femur rod with realignment and noted restoration of the left femur cortical thickness. CONCLUSION We demonstrate the significant functional impact of stress shielding and its evolution over a protracted period and outline treatment principles. To our knowledge, this is the first report of treatment of stress shielding of a long bone in the setting of OI.
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Affiliation(s)
- Jeanne M Franzone
- Department of Orthopaedic Surgery, Nemours/Alfred I. duPont Hospital for Children, Wilmington, Delaware
| | - Brandi M Sargent
- Heritable Disorders of Bone and Extracellular Matrix, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland
- Pediatric Residency Program, University of Maryland Medical Center, Baltimore, Maryland
| | - An N Dang Do
- National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland
| | - Marianne Knue
- Pediatric Residency Program, University of Maryland Medical Center, Baltimore, Maryland
| | - Joan C Marini
- Heritable Disorders of Bone and Extracellular Matrix, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland
| | - Richard W Kruse
- Department of Orthopaedic Surgery, Nemours/Alfred I. duPont Hospital for Children, Wilmington, Delaware
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9
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Abdennadher M, Inati S, Soldatos A, Norato G, Baker EH, Thurm A, Bartolini L, Masvekar R, Theodore W, Bielekova B, Porter FD, Dang Do AN. Seizure phenotype in CLN3 disease and its relation to other neurologic outcome measures. J Inherit Metab Dis 2021; 44:1013-1020. [PMID: 33550636 PMCID: PMC9437865 DOI: 10.1002/jimd.12366] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Revised: 02/03/2021] [Accepted: 02/05/2021] [Indexed: 11/12/2022]
Abstract
CLN3 disease is a pediatric neurodegenerative condition wherein seizures are common. The most common disease-causing variant is an ~1-kb deletion in CLN3. We investigated seizure phenotype in relation to genotype and to adaptive behavior, MR spectroscopy and CSF biochemical markers in a CLN3 cohort. We performed seizure phenotyping using clinical history, EEG, and the Unified Batten Disease Rating Scale (UBDRS) seizure score. We assessed correlations of seizure severity with disease severity (UBDRS capability), adaptive behavior composite score (ABC; Vineland-3), glutamate+glutamine+GABA and N-acetylaspartate+N-acetylaspartyl glutamate (MR spectroscopy), and CSF neurofilament light chain (NEFL) levels. In 20 participants, median age was 10.7 years (IQR = 7.8). Eighteen completed baseline EEG; 12 had a 1-year follow-up. Seizures were reported in 14 (8 1-kb deletion homozygotes), with median age at onset of 10.0 (IQR = 6.8). Epileptiform discharges were noted in 15 (9 homozygotes). Bilateral tonic clonic (n = 11) and nonmotor seizures (n = 7) were most common. UBDRS seizure score correlated with age (rp = 0.50; [0.08,0.77]; P = .02), UBDRS capability (rp = -0.57; [-0.81,-0.17]; P = .009) and ABC (rp = -0.66; [-0.85,-0.31]; P = .001) scores, glutamate+glutamine+GABA (rp = -0.54; [-0.80,-0.11]; P = .02) and N-acetylaspartate+N-acetylaspartyl glutamate (rp = -0.54; [-0.80,-0.11]; P = .02), and CSF NEFL (rp = 0.65; [0.29,0.85]; P = .002) levels. After controlling for age, correlations with ABC and CSF NEFL remained significant. In our CLN3 cohort, seizures and epileptiform discharges were frequent and often started by age 10 years without significant difference between genotypes. ABC and CSF NEFL correlate with UBDRS seizure score, reflecting the role of seizures in the neurodegenerative process. Longitudinal evaluations in a larger cohort are needed to confirm these findings.
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Affiliation(s)
- Myriam Abdennadher
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, USA
- Department of Neurology, Boston Medical Center; Boston University School of Medicine, Boston, MA, USA
| | - Sara Inati
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, USA
| | - Ariane Soldatos
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, USA
| | - Gina Norato
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, USA
| | - Eva H. Baker
- Radiology and Imaging Sciences Department, Clinical Center, NIH, Bethesda, Maryland, USA
| | - Audrey Thurm
- National Institute of Mental Health, NIH, Bethesda, Maryland, USA
| | - Luca Bartolini
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, USA
- Division of Pediatric Neurology, Hasbro Children’s Hospital; The Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - Ruturaj Masvekar
- National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, USA
| | - William Theodore
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland, USA
| | - Bibiana Bielekova
- National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, USA
| | - Forbes D. Porter
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Bethesda, Maryland, USA
| | - An N. Dang Do
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Bethesda, Maryland, USA
- Correspondence: An Ngoc Dang Do, MD PhD, 10 Center Drive, MSC 1103. Bethesda, MD 20892, Phone: 301.496.8849, Fax: 301.402.0574,
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Hildenbrand H, Wickstrom J, Parks R, Zampieri C, Nguyen TT, Thurm A, Jenkins K, Alter KE, Matsubara J, Hammond D, Soldatos A, Porter FD, Dang Do AN. Characterizing upper limb function in the context of activities of daily living in CLN3 disease. Am J Med Genet A 2021; 185:1399-1413. [PMID: 33559393 DOI: 10.1002/ajmg.a.62114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 01/15/2021] [Accepted: 01/23/2021] [Indexed: 11/06/2022]
Abstract
In CLN3 disease, impairments in motor function are frequently reported to have later onset compared to visual and cognitive decline, but upper limb motor function has yet to be explored in this population. In a cohort of 22 individuals with CLN3, we used a novel application of multiple measures to (1) characterize motor function, particularly of the upper limbs, in activities of daily living (ADLs), and (2) explore associations between motor function and age as well as visual ability, disease severity, and cognitive function, as evaluated by the Unified Batten Disease Rating Scale (UBDRS), a validated CLN3 disease measure. ADLs that required coordination, speed, and fine motor control were particularly challenging for children with CLN3 based on item-level performance across direct assessments (Jebsen-Taylor Hand Function Test [JTHFT] and MyoSet Tools) and caregiver reports (Pediatric Evaluation of Disability Inventory-Computer Adaptive Testing [PEDI-CAT] and Patient-Reported Outcomes Measurement Information System [PROMIS] Pediatric Upper Extremity). Poorer visual ability, disease severity, and cognitive function were associated with worse performance on these measures, whereas age had limited impact. These findings support the need for children with CLN3 to receive skilled clinical evaluation and treatment tailored to their individual needs, particularly in the context of ADLs, as their symptom profile progresses.
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Affiliation(s)
- Hanna Hildenbrand
- Department of Rehabilitation Medicine, Clinical Center, National Institutes of Health, Bethesda, Maryland, USA
| | - Jordan Wickstrom
- Department of Rehabilitation Medicine, Clinical Center, National Institutes of Health, Bethesda, Maryland, USA
| | - Rebecca Parks
- Department of Rehabilitation Medicine, Clinical Center, National Institutes of Health, Bethesda, Maryland, USA
| | - Cris Zampieri
- Department of Rehabilitation Medicine, Clinical Center, National Institutes of Health, Bethesda, Maryland, USA
| | - Thuy-Tien Nguyen
- Department of Rehabilitation Medicine, Clinical Center, National Institutes of Health, Bethesda, Maryland, USA
| | - Audrey Thurm
- Neurodevelopmental and Behavioral Phenotyping Service, National Institutes of Mental Health, National Institutes of Health, Bethesda, Maryland, USA
| | - Kisha Jenkins
- Office of the Clinical Director, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA
| | - Katharine E Alter
- Department of Rehabilitation Medicine, Clinical Center, National Institutes of Health, Bethesda, Maryland, USA
| | - Jesse Matsubara
- Department of Rehabilitation Medicine, Clinical Center, National Institutes of Health, Bethesda, Maryland, USA
| | - Dylan Hammond
- Office of the Clinical Director, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA
| | - Ariane Soldatos
- Pediatric Neurology Consultation Service, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
| | - Forbes D Porter
- Office of the Clinical Director, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA
| | - An N Dang Do
- Office of the Clinical Director, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA
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Dang Do AN, Sinaii N, Masvekar RR, Baker EH, Thurm AE, Soldatos AG, Bianconi SE, Bielekova B, Porter FD. Neurofilament light chain levels correlate with clinical measures in CLN3 disease. Genet Med 2020; 23:751-757. [PMID: 33239751 PMCID: PMC8035240 DOI: 10.1038/s41436-020-01035-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 10/23/2020] [Accepted: 10/27/2020] [Indexed: 11/09/2022] Open
Abstract
PURPOSE CLN3 disease is a neurodegenerative disorder with onset in childhood. It affects multiple functions at different developmental stages. Incomplete understanding of the pathophysiology hampers identification of cell and tissue biochemical compounds reflective of the disease process. As treatment approaches are being explored, more sensitive, objective, quantifiable, and clinically relevant biomarkers are needed. METHODS We collected prospective biosamples from 21 phenotyped individuals with CLN3. We measured neurofilament light chain (NEFL) levels, a marker of neuronal damage, in cross-sectional CSF and serum samples from individuals with CLN3 and in pediatric non-CLN3 controls using two different assays. RESULTS Cerebrospinal fluid (CSF) and serum NEFL levels are significantly higher in CLN3 (CSF: 2096 ± 1202; serum: 29.0 ± 18.0 pg/mL) versus similarly aged non-CLN3 (CSF: 345 ± 610; serum: 6.7 ± 3.2 pg/mL) samples. NEFL levels correlate with Unified Batten Disease Rating Scale and adaptive behavior composite scores, and magnetic resonance (MR) spectroscopy markers. NEFL levels from CSF and serum are strongly correlated (rp = 0.83; p < 0.0001). CONCLUSION CSF and serum NEFL levels increase in multiple neurologic conditions. Here, we show that CSF and serum NEFL levels also increase in CLN3 (versus non-CLN3) and correlate with other disease-relevant measures. These findings suggest NEFL as a relevant and feasible biomarker for applications in CLN3 clinical trials and management.
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Affiliation(s)
- An N Dang Do
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Bethesda, MD, USA.
| | - Ninet Sinaii
- Biostatistics and Clinical Epidemiology Service, Clinical Center, NIH, Bethesda, MD, USA
| | - Ruturaj R Masvekar
- National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, USA
| | - Eva H Baker
- Radiology and Imaging Sciences Department, Clinical Center, NIH, Bethesda, MD, USA
| | - Audrey E Thurm
- National Institute of Mental Health, NIH, Bethesda, MD, USA
| | - Ariane G Soldatos
- National Institute of Neurological Disorders and Stroke, NIH, Bethesda, MD, USA
| | - Simona E Bianconi
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Bethesda, MD, USA
| | - Bibiana Bielekova
- National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, USA
| | - Forbes D Porter
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, Bethesda, MD, USA
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Barber LA, Abbott C, Nakhate V, Do AND, Blissett AR, Marini JC. Longitudinal growth curves for children with classical osteogenesis imperfecta (types III and IV) caused by structural pathogenic variants in type I collagen. Genet Med 2018; 21:1233-1239. [PMID: 30270360 DOI: 10.1038/s41436-018-0307-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 09/04/2018] [Indexed: 11/09/2022] Open
Abstract
PURPOSE Growth deficiency is a cardinal feature of osteogenesis imperfecta (OI) types III and IV, caused by pathogenic variants in type I collagen. OI-specific longitudinal growth charts are needed for patient care. METHODS We compiled longitudinal length, weight, head circumference, and body mass index (BMI) data from 100 children with types III and IV OI and known type I collagen pathogenic variants. Effects of gender, OI type, and pathogenic variant were examined using multilevel modeling. OI-specific centile curves were constructed using generalized additive model for location, scale, and shape (GAMLSS). RESULTS OI type and gender, but not the specific mutated collagen gene, significantly affect stature, but only OI type affects weight. Head circumference was not significantly different by gender, type, or mutated gene. In both genders, length curves for types III and IV OI overlap and the type IV 95th centile curve overlaps the lower US Centers for Disease Control and Prevention (CDC) curves for the general population. A pubertal growth spurt is generally absent or blunted in types III/IV OI. The body mass index 50th and 95th centile curves are distinctly shifted above respective US CDC curves in both genders. CONCLUSIONS OI type is a stronger contributing factor than gender for OI growth, while curves do not differ for COL1A1 versus COL1A2 pathogenic variants. Types III and IV OI-specific growth curves are presented.
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Affiliation(s)
- Lauren A Barber
- Section on Heritable Disorders of Bone and Extracellular Matrix, NICHD, NIH, Bethesda, MD, USA.,Hospital for Special Surgery, New York, NY, USA
| | - Craig Abbott
- Office of the Clinical Director, NICHD, NIH, Bethesda, MD, USA
| | - Vihang Nakhate
- Section on Heritable Disorders of Bone and Extracellular Matrix, NICHD, NIH, Bethesda, MD, USA.,Harvard Medical School, Boston, MA, USA
| | - An N Dang Do
- Office of the Clinical Director, NICHD, NIH, Bethesda, MD, USA
| | - Angela R Blissett
- Section on Heritable Disorders of Bone and Extracellular Matrix, NICHD, NIH, Bethesda, MD, USA.,The Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - Joan C Marini
- Section on Heritable Disorders of Bone and Extracellular Matrix, NICHD, NIH, Bethesda, MD, USA.
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Dang Do AN, Baker EH, Warren KE, Bianconi SE, Porter FD. Spontaneously regressing brain lesions in Smith-Lemli-Opitz syndrome. Am J Med Genet A 2017; 176:386-390. [PMID: 29226552 DOI: 10.1002/ajmg.a.38563] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 11/07/2017] [Accepted: 11/08/2017] [Indexed: 11/10/2022]
Abstract
Smith-Lemli-Opitz syndrome (SLOS) is a metabolic disorder caused by an inborn error of cholesterol synthesis that affects the development of many organ systems. Malformations in the central nervous system typically involve midline structures and reflect abnormal growth and differentiation of neurons and supporting cells. Despite these defects in central nervous system development, brain tumor formation has only rarely been reported in association with SLOS. We present three individuals with SLOS and lesions in the basal ganglia or brainstem detected by MRI that were concerning for tumor formation. However, the individuals' clinical and neurological course remained stable, and the lesions regressed after several years. These lesions have similarities to spongiotic changes observed in individuals with neurofibromatosis type 1 (NF1). Notably, impaired activity of small GTPases is present in both SLOS and NF1, perhaps giving mechanistic insight into the formation of these lesions.
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Affiliation(s)
- An N Dang Do
- Division of Translational Research, Eunice Kennedy Shriver National Institute of Human Development (NICHD), National Institutes of Health, Bethesda, Maryland
| | - Eva H Baker
- Department of Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, Maryland
| | - Katherine E Warren
- Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Simona E Bianconi
- Division of Translational Research, Eunice Kennedy Shriver National Institute of Human Development (NICHD), National Institutes of Health, Bethesda, Maryland
| | - Forbes D Porter
- Division of Translational Research, Eunice Kennedy Shriver National Institute of Human Development (NICHD), National Institutes of Health, Bethesda, Maryland
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Dang Do AN, Munchhof AM, Terry C, Emmett T, Kara A. Research and publication trends in hospital medicine. J Hosp Med 2014; 9:148-54. [PMID: 24591288 DOI: 10.1002/jhm.2148] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2013] [Revised: 11/20/2013] [Accepted: 12/17/2013] [Indexed: 11/08/2022]
Abstract
BACKGROUND Research by hospitalists may aid the evolution of hospital medicine into an academic specialty. OBJECTIVE To describe the factors associated with research and publication activities among hospitalists and describe trends in hospitalist-led publications. METHODS We surveyed members of the Society of Hospital Medicine in June 2012 and conducted univariate analyses on their responses to determine predictors of successful authorship and to describe factors associated with research engagement. We searched PubMed from the database inception to October 2013 for publications with "hospitalist" or "hospital medicine" affiliated authors. Original research articles were reviewed for methodology and funding sources. RESULTS Of the 645 respondents (5.8% response rate), 277 (43%) had authored peer-reviewed publications, 126 (19%) had access to mentorship, and 68 (11%) reported funding support. There were 213 (33%) who were engaged in research, with the majority conducting quality improvement (QI) research (n = 152, 24%). Completion of a fellowship, pediatrics training, the presence of a mentor, funding, and >25% protected time for research were each individually associated with an increased likelihood of authoring publications. Hospitalist-led publications in PubMed have been increasing from 36 in 2006 to 179 in the first 10 months of 2013. Of the original research publications (n = 317), the majority were clinical (n = 129, 41%), and 58 (18%) were QI. Thirty-nine (22%) authors reported funding support. CONCLUSIONS Peer-reviewed publications by hospitalists are increasing, suggesting the academic maturation of hospital medicine. Provision of mentorship for hospitalists specifically in QI and guidance toward funding resources may assist in supporting this trend.
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Affiliation(s)
- An N Dang Do
- Internal Medicine-Pediatric Residency Program, Indiana University School of Medicine, Indianapolis, Indiana
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Dang Do AN, Kimball SR, Cavener DR, Jefferson LS. eIF2alpha kinases GCN2 and PERK modulate transcription and translation of distinct sets of mRNAs in mouse liver. Physiol Genomics 2009; 38:328-41. [PMID: 19509078 DOI: 10.1152/physiolgenomics.90396.2008] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
In eukaryotes, selective derepression of mRNA translation through altered utilization of upstream open reading frames (uORF) or internal ribosomal entry sites (IRES) regulatory motifs following exposure to stress is regulated at the initiation stage through the increased phosphorylation of eukaryotic initiation factor 2 on its alpha-subunit (eIF2alpha). While there is only one known eIF2alpha kinase in yeast, general control nonderepressible 2 (GCN2), mammals have evolved to express at least four: GCN2, heme-regulated inhibitor kinase (HRI), double-stranded RNA-activated protein kinase (PKR), and PKR-like endoplasmic reticulum-resident kinase (PERK). So far, the main known distinction among these four kinases is their activation in response to different acute stressors. In the present study, we used the in situ perfused mouse liver model and hybridization array analyses to assess the general translational response to stress regulated by two of these kinases, GCN2 and PERK, and to differentiate between the downstream effects of activating GCN2 versus PERK. The resulting data showed that at least 2.5% of mouse liver mRNAs are subject to derepressed translation following stress. In addition, the data demonstrated that eIF2alpha kinases GCN2 and PERK differentially regulate mRNA transcription and translation, which in the latter case suggests that increased eIF2alpha phosphorylation is not sufficient for derepression of translation. These findings open an avenue for more focused future research toward groups of mRNAs that code for the early cellular stress response proteins.
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Affiliation(s)
- An N Dang Do
- Department of Cellular and Molecular Physiology, Pennsylvania State University College of Medicine, Hershey, USA
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