21 results on '"Bichell TJ"'
Search Results
2. Koolen-de Vries Syndrome: a journey from diagnosis to treatments.
- Author
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Pfalzer AC, Ivers B, Haynam A, Drake B, Koolen DA, Kasri NN, de Vries BBA, Mefford HC, Morgan A, Bichell TJ, Simon E, Terala A, Myers KA, and Point A
- Abstract
The Koolen-de Vries Syndrome Foundation was founded in 2013 with the mission to educate, increase awareness, promote research and develop treatments for individuals living with Koolen-de Vries Syndrome (KdVS) and their families. With this aim, the foundation has focused on: developing scientific resources through patient cell and animal models, providing seed funding to basic and clinical researchers, establishing a natural history study of KdVS and increasing patient engagement. Projects have been prioritized across these areas of focus with an emphasis on expanding international research on KdVS, supporting translational research, establishing an international natural history study and conducting studies to assess patient priorities. With the incredible growth amongst our research and patient community in the last decade, our goal is to have our first clinical trial for KdVS in 2026., Competing Interests: The authors declare that there is no conflict of interest. All material generated by the Foundation will be provided to interested researchers upon request or already available on the Foundation website.8, (© The Author(s), 2024.)
- Published
- 2024
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3. Enabling endpoint development for interventional clinical trials in individuals with Angelman syndrome: a prospective, longitudinal, observational clinical study (FREESIAS).
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Tjeertes J, Bacino CA, Bichell TJ, Bird LM, Bustamante M, Crean R, Jeste S, Komorowski RW, Krishnan ML, Miller MT, Nobbs D, Ochoa-Lubinoff C, Parkerson KA, Rotenberg A, Sadhwani A, Shen MD, Squassante L, Tan WH, Vincenzi B, Wheeler AC, Hipp JF, and Berry-Kravis E
- Subjects
- Humans, Prospective Studies, Pandemics, Electroencephalography, Angelman Syndrome complications, COVID-19
- Abstract
Background: Angelman syndrome (AS) is a rare neurodevelopmental disorder characterized by the absence of a functional UBE3A gene, which causes developmental, behavioral, and medical challenges. While currently untreatable, comprehensive data could help identify appropriate endpoints assessing meaningful improvements in clinical trials. Herein are reported the results from the FREESIAS study assessing the feasibility and utility of in-clinic and at-home measures of key AS symptoms., Methods: Fifty-five individuals with AS (aged < 5 years: n = 16, 5-12 years: n = 27, ≥ 18 years: n = 12; deletion genotype: n = 40, nondeletion genotype: n = 15) and 20 typically developing children (aged 1-12 years) were enrolled across six USA sites. Several clinical outcome assessments and digital health technologies were tested, together with overnight 19-lead electroencephalography (EEG) and additional polysomnography (PSG) sensors. Participants were assessed at baseline (Clinic Visit 1), 12 months later (Clinic Visit 2), and during intermittent home visits., Results: The participants achieved high completion rates for the clinical outcome assessments (adherence: 89-100% [Clinic Visit 1]; 76-91% [Clinic Visit 2]) and varied feasibility of and adherence to digital health technologies. The coronavirus disease 2019 (COVID-19) pandemic impacted participants' uptake of and/or adherence to some measures. It also potentially impacted the at-home PSG/EEG recordings, which were otherwise feasible. Participants achieved Bayley-III results comparable to the available natural history data, showing similar scores between individuals aged ≥ 18 and 5-12 years. Also, participants without a deletion generally scored higher on most clinical outcome assessments than participants with a deletion. Furthermore, the observed AS EEG phenotype of excess delta-band power was consistent with prior reports., Conclusions: Although feasible clinical outcome assessments and digital health technologies are reported herein, further improved assessments of meaningful AS change are needed. Despite the COVID-19 pandemic, remote assessments facilitated high adherence levels and the results suggested that at-home PSG/EEG might be a feasible alternative to the in-clinic EEG assessments. Taken altogether, the combination of in-clinic/at-home clinical outcome assessments, digital health technologies, and PSG/EEG may improve protocol adherence, reduce patient burden, and optimize study outcomes in AS and other rare disease populations., (© 2023. The Author(s).)
- Published
- 2023
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4. A disease concept model for STXBP1-related disorders.
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Sullivan KR, Ruggiero SM, Xian J, Thalwitzer KM, Ali R, Stewart S, Cosico M, Steinberg J, Goss J, Pfalzer AC, Horning KJ, Weitzel N, Corey S, Conway L, Rigby CS, Bichell TJ, and Helbig I
- Subjects
- Humans, Seizures genetics, Caregivers, Socialization, Munc18 Proteins genetics, Epilepsy genetics, Neurodevelopmental Disorders genetics
- Abstract
Objective: STXBP1-related disorders are rare genetic epilepsies and neurodevelopmental disorders, but the impact of symptoms across clinical domains is poorly understood. Disease concept models are formal frameworks to assess the lived experience of individuals and their families and provide a basis for generating outcome measures., Methods: We conducted semistructured, qualitative interviews with 19 caregivers of 16 individuals with STXBP1-related disorders and 7 healthcare professionals. We systematically coded themes using NVivo software and grouped concepts into the domains of symptoms, symptom impact, and caregiver impact. We quantified the frequency of concepts throughout the lifespan and across clinical subgroups stratified by seizure history and developmental trajectories., Results: Over 25 hours of interviews, we coded a total of 3626 references to 38 distinct concepts. In addition to well-recognized clinical features such as developmental delay (n = 240 references), behavior (n = 201), and seizures (n = 147), we identified previously underrepresented symptoms including gastrointestinal (n = 68) and respiratory symptoms (n = 24) and pain (n = 30). The most frequently referenced symptom impacts were autonomy (n = 96), socialization (n = 64), and schooling (n = 61). Emotional impact (n = 354), support (n = 200), and daily life & activities (n = 108) were highly cited caregiver impacts. We found that seizures were more commonly referenced in infancy than in other age groups, while behavior and socialization were more likely to be referred to in childhood. We found that caregivers of individuals with ongoing seizures were less likely to reference developmental delay, possibly due to the relatively high impact of seizures., Significance: STXBP1-related disorders are complex conditions affecting a wide range of clinical and social domains. We comprehensively mapped symptoms and their impact on families to generate a comprehensive disease model as a foundation for clinical endpoints in future trials., (© 2023 The Authors. Epilepsia Open published by Wiley Periodicals LLC on behalf of International League Against Epilepsy.)
- Published
- 2023
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5. Patterns of developmental regression and associated clinical characteristics in SLC6A1-related disorder.
- Author
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Kalvakuntla S, Lee M, Chung WK, Demarest S, Freed A, Horning KJ, Bichell TJ, Iannaccone ST, and Goodspeed K
- Abstract
Introduction: SLC6A1-related disorder is a genetic neurodevelopmental disorder that is caused by loss of function variants in the SLC6A1 gene. Solute Carrier Family 6 Member 1 ( SLC6A1 ) gene encodes for gamma-aminobutyric acid (GABA) transporter type 1 (GAT1), which is responsible for reuptake of GABA from the synaptic cleft. Tight regulation of GABA levels plays an important role in brain development by balancing inhibitory and excitatory neuronal signaling. Consequently, individuals with SLC6A1-related disorder can have manifestations such as developmental delay, epilepsy, autism spectrum disorder, and a subset have developmental regression., Methods: In this study, we identified patterns of developmental regression among a cohort of 24 patients with SLC6A1-related disorder and assessed for clinical characteristics associated with regression. We reviewed medical records of patients with SLC6A1-related disorder and divided subjects into two groups: 1) regression group and 2) control group. We described the patterns of developmental regression including whether there was a trigger prior to the regression, multiple episodes of regression, and whether or not skills were recovered. We assessed the relationship of clinical characteristics among the regression and control groups including demographic factors, seizures, developmental milestone acquisition, gastrointestinal problems, sleep problems, autism spectrum disorder, and behavioral problems., Results: Individuals with developmental regression had a loss of skills that were previously mastered in developmental domains including speech and language, motor, social, and adaptive skills. The mean age at regression was 2.7 years and most subjects had regression of language or motor skills triggered by seizures, infection, or spontaneously. Although there was no significant difference in clinical characteristics between the two groups, there was a higher prevalence of autism and severe language impairment in the regression group., Discussion: Future studies of a larger cohort of patients are required to make definitive conclusions. Developmental regression is often a sign of severe neurodevelopmental disability in genetic syndromes, but it is poorly understood in SLC6A1-related disorder. Understanding the patterns of developmental regression and the associated clinical characteristics in this rare disorder will be important to medical management, prognostication, and could impact the design of future clinical trials., Competing Interests: KG has received research support from SLC6A1 Connect and Taysha Gene Therapies on related subject matter, and consulted for Jaguar Gene Therapy, AllStripes, and Astellas Gene Therapy on unrelated subject matter. She also serves on the advisory board for the non-profit organization, COMBINEDBrain. SD has consulted for Biomarin and Neurogene, Taysha Gene Therapies, Ultragenyx, and Zogenix on unrelated subject matter and Marinus and Ovid Therapeutics on a related subject matter. He has funding from the NIH, International Foundation for CDKL5 Research, Mila’s Miracle Foundation, and Project 8P. He also serves on the advisory board for the non-profit foundations SLC6A1 Connect, Project 8P, Ring14 USA, and FamilieSCN2A. WC has served on scientific advisory boards for Taysha Gene Therapies and Jaguar Gene Therapy. AF is the founder of the non-profit foundation, SLC6A1 Connect. TB is the founder of the non-profit organization, COMBINEDBrain. KH is affiliated with the non-profit organization COMBINEDBrain. SI has received personal compensation for service on advisory boards or consulting from Novartis Gene Therapies, Inc., Biogen, Roche/Genentech, and Sarepta Therapeutics; and research support from Novartis Gene Therapies, Inc., Biogen, Capricor Therapeutics, Inc., PTC, Scholar Rock, and Sarepta Therapeutics. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Kalvakuntla, Lee, Chung, Demarest, Freed, Horning, Bichell, Iannaccone and Goodspeed.)
- Published
- 2023
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6. Treatment with THI, an inhibitor of sphingosine-1-phosphate lyase, modulates glycosphingolipid metabolism and results therapeutically effective in experimental models of Huntington's disease.
- Author
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Pepe G, Capocci L, Marracino F, Realini N, Lenzi P, Martinello K, Bovier TF, Bichell TJ, Scarselli P, Di Cicco C, Bowman AB, Digilio FA, Fucile S, Fornai F, Armirotti A, Parlato R, Di Pardo A, and Maglione V
- Subjects
- Mice, Humans, Animals, Models, Theoretical, Imidazoles pharmacology, Glycosphingolipids, Disease Models, Animal, Huntingtin Protein genetics, Huntington Disease drug therapy
- Abstract
Huntington's disease (HD) is a fatal neurodegenerative disorder with no effective cure currently available. Over the past few years our research has shown that alterations in sphingolipid metabolism represent a critical determinant in HD pathogenesis. In particular, aberrant metabolism of sphingosine-1-phosphate (S1P) has been reported in multiple disease settings, including human postmortem brains from HD patients. In this study, we investigate the potential therapeutic effect of the inhibition of S1P degradative enzyme SGPL1, by the chronic administration of the 2-acetyl-5-tetrahydroxybutyl imidazole (THI) inhibitor. We show that THI mitigated motor dysfunctions in both mouse and fly models of HD. The compound evoked the activation of pro-survival pathways, normalized levels of brain-derived neurotrophic factor, preserved white matter integrity, and stimulated synaptic functions in HD mice. Metabolically, THI restored normal levels of hexosylceramides and stimulated the autophagic and lysosomal machinery, facilitating the reduction of nuclear inclusions of both wild-type and mutant huntingtin proteins., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2022 The American Society of Gene and Cell Therapy. Published by Elsevier Inc. All rights reserved.)
- Published
- 2023
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7. Measuring What Matters to Individuals with Angelman Syndrome and Their Families: Development of a Patient-Centered Disease Concept Model.
- Author
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Willgoss T, Cassater D, Connor S, Krishnan ML, Miller MT, Dias-Barbosa C, Phillips D, McCormack J, Bird LM, Burdine RD, Claridge S, and Bichell TJ
- Subjects
- Caregivers, Humans, Models, Theoretical, Patient-Centered Care, Qualitative Research, Angelman Syndrome
- Abstract
Angelman syndrome (AS) is a complex, heterogeneous, and life-long neurodevelopmental disorder. Despite the considerable impact on individuals and caregivers, no disease-modifying treatments are available. To support holistic clinical management and the development of AS-specific outcome measures for clinical studies, we conducted primary and secondary research identifying the impact of symptoms on individuals with AS and their unmet need. This qualitative research adopted a rigorous step-wise approach, aggregating information from published literature, then evaluating it via disease concept elicitation interviews with clinical experts and caregivers. We found that the AS-defining concepts most relevant for treatment included: impaired expressive communication, seizures, maladaptive behavior, cognitive impairment, motor function difficulties, sleep disturbance, and limited self-care abilities. We highlight the relevance of age in experiencing these key AS concepts, and the difference between the perceptions of clinicians and caregivers towards the syndrome. Finally, we outline the impact of AS on individuals, caregivers, and families.
- Published
- 2021
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8. A placebo-controlled trial of folic acid and betaine in identical twins with Angelman syndrome.
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Han J, Bichell TJ, Golden S, Anselm I, Waisbren S, Bacino CA, Peters SU, Bird LM, and Kimonis V
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- Betaine administration & dosage, Child, Double-Blind Method, Folic Acid administration & dosage, Gastrointestinal Agents administration & dosage, Gastrointestinal Agents therapeutic use, Humans, Male, Sequence Deletion, Twins, Monozygotic, Vitamin B Complex administration & dosage, Vitamin B Complex therapeutic use, Angelman Syndrome drug therapy, Betaine therapeutic use, Folic Acid therapeutic use
- Abstract
Background: Angelman syndrome (AS) is a neurodevelopmental disorder that is caused by maternal genetic deficiency of a gene that encodes E6-AP ubiquitin-protein ligase (gene symbol UBE3A) mapping to chromosome 15q11-q13. AS leads to stiff and jerky gait, excess laughter, seizures, and severe intellectual disability. In some parts of the brain, the paternally inherited UBE3A gene is subject to genomic imprinting by the action of the UBE3A-antisense transcript (UBE3A-ATS) on the paternally inherited allele. Consequently, only the maternally inherited UBE3A gene is expressed in mature neurons. AS occurs due to deletions of the maternal 15q11 - 13 region, paternal uniparental disomy (UPD), imprinting center defects, mutations in the maternal UBE3A gene, or other unknown genetic malfunctions that result in a silenced maternal UBE3A gene in the specific imprinted regions of the brain., Results: A potential treatment strategy for AS is to increase methylation of UBE3A-ATS to promote expression of the paternal UBE3A gene and thus ameliorate the clinical phenotypes of AS. We treated two sets of male identical twins with class I deletions with a 1 year treatment trial of either betaine and folic acid versus placebo. We found no statistically significant changes in the clinical parameters tested at the end of the 1 year trial, nor did we find any significant adverse events., Conclusions: This study tested the hypothesis that by increasing the methylation of the UBE3A-antisense transcript in Angelman syndrome to promote expression of the silenced paternal UBE3A gene we may ameliorate the clinical phenotypes of AS. We treated two sets of identical twins with placebo versus betaine and folic acid. Although this study represented a novel approach to treating Angelman syndrome, the differences in the developmental testing results was not significant. This paper also discusses the value of monozygotic twin studies in minimizing confounding variables and its utility in conducting small treatment studies., Trial Registration: NCT00348933 . Registered 6 July 2006.
- Published
- 2019
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9. Beyond Epilepsy and Autism: Disruption of GABRB3 Causes Ocular Hypopigmentation.
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Delahanty RJ, Zhang Y, Bichell TJ, Shen W, Verdier K, Macdonald RL, Xu L, Boyd K, Williams J, and Kang JQ
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- Angelman Syndrome complications, Angelman Syndrome genetics, Angelman Syndrome pathology, Animals, Autistic Disorder complications, Autistic Disorder pathology, Epilepsy complications, Epilepsy pathology, Genetic Predisposition to Disease, Genomic Imprinting, Humans, Hypopigmentation pathology, Membrane Transport Proteins genetics, Mice, Mutation, Prader-Willi Syndrome complications, Prader-Willi Syndrome genetics, Prader-Willi Syndrome pathology, Autistic Disorder genetics, Epilepsy genetics, Hypopigmentation genetics, Receptors, GABA-A genetics
- Abstract
Reduced ocular pigmentation is common in Angelman syndrome (AS) and Prader-Willi syndrome (PWS) and is long thought to be caused by OCA2 deletion. GABRB3 is located in the 15q11-13 region flanked by UBE3A, GABRA5, GABRG3, and OCA2. Mutations in GABRB3 have frequently been associated with epilepsy and autism, consistent with its role in neurodevelopment. We report here a robust phenotype in the mouse in which deletion of Gabrb3 alone causes nearly complete loss of retinal pigmentation due to atrophied melanosomes, as evidenced by electron microscopy. Using exome and RNA sequencing, we confirmed that only the Gabrb3 gene was disrupted while the Oca2 gene was intact. However, mRNA abundance of Oca2 and other genes adjacent to Gabrb3 is substantially reduced in Gabrb3
-/- mice, suggesting complex transcriptional regulation in this region. These results suggest that impairment in GABRB3 downregulates OCA2 and indirectly causes ocular hypopigmentation and visual defects in AS and PWS., (Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.)- Published
- 2016
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10. Embryonic Mutant Huntingtin Aggregate Formation in Mouse Models of Huntington's Disease.
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Osmand AP, Bichell TJ, Bowman AB, and Bates GP
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- Animals, Axons metabolism, Axons pathology, Brain pathology, Disease Models, Animal, Huntington Disease pathology, Immunohistochemistry, Mice, Transgenic, Protein Aggregation, Pathological embryology, Protein Aggregation, Pathological metabolism, Protein Aggregation, Pathological pathology, Brain embryology, Brain metabolism, Huntingtin Protein metabolism, Huntington Disease embryology, Huntington Disease metabolism
- Abstract
The role of aggregate formation in the pathophysiology of Huntington's disease (HD) remains uncertain. However, the temporal appearance of aggregates tends to correlate with the onset of symptoms and the numbers of neuropil aggregates correlate with the progression of clinical disease. Using highly sensitive immunohistochemical methods we have detected the appearance of diffuse aggregates during embryonic development in the R6/2 and YAC128 mouse models of HD. These are initially seen in developing axonal tracts and appear to spread throughout the cerebrum in the early neonate.
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- 2016
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11. Allosteric activation of M4 muscarinic receptors improve behavioral and physiological alterations in early symptomatic YAC128 mice.
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Pancani T, Foster DJ, Moehle MS, Bichell TJ, Bradley E, Bridges TM, Klar R, Poslusney M, Rook JM, Daniels JS, Niswender CM, Jones CK, Wood MR, Bowman AB, Lindsley CW, Xiang Z, and Conn PJ
- Subjects
- Animals, Brain metabolism, Fluorescence, Huntington Disease physiopathology, Immunohistochemistry, Mice, Mice, Mutant Strains, Pyridazines pharmacology, Pyridazines therapeutic use, Rotarod Performance Test, Synaptic Transmission drug effects, Thiophenes pharmacology, Thiophenes therapeutic use, Allosteric Regulation physiology, Glutamic Acid metabolism, Huntington Disease drug therapy, Receptor, Muscarinic M4 physiology, Synaptic Transmission physiology
- Abstract
Mutations that lead to Huntington's disease (HD) result in increased transmission at glutamatergic corticostriatal synapses at early presymptomatic stages that have been postulated to set the stage for pathological changes and symptoms that are observed at later ages. Based on this, pharmacological interventions that reverse excessive corticostriatal transmission may provide a novel approach for reducing early physiological changes and motor symptoms observed in HD. We report that activation of the M4 subtype of muscarinic acetylcholine receptor reduces transmission at corticostriatal synapses and that this effect is dramatically enhanced in presymptomatic YAC128 HD and BACHD relative to wild-type mice. Furthermore, chronic administration of a novel highly selective M4 positive allosteric modulator (PAM) beginning at presymptomatic ages improves motor and synaptic deficits in 5-mo-old YAC128 mice. These data raise the exciting possibility that selective M4 PAMs could provide a therapeutic strategy for the treatment of HD.
- Published
- 2015
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12. Ube3a imprinting impairs circadian robustness in Angelman syndrome models.
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Shi SQ, Bichell TJ, Ihrie RA, and Johnson CH
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- ARNTL Transcription Factors metabolism, Analysis of Variance, Angelman Syndrome genetics, Animals, Body Weight physiology, Chronotherapy methods, Circadian Rhythm drug effects, Circadian Rhythm genetics, Gene Deletion, Humans, Liver metabolism, Mice, Sleep Wake Disorders therapy, Angelman Syndrome physiopathology, Circadian Rhythm physiology, Genomic Imprinting genetics, Neurons metabolism, Ubiquitin-Protein Ligases genetics
- Abstract
Background: The paternal allele of Ube3a is silenced by imprinting in neurons, and Angelman syndrome (AS) is a disorder arising from a deletion or mutation of the maternal Ube3a allele, which thereby eliminates Ube3a neuronal expression. Sleep disorders such as short sleep duration and increased sleep onset latency are very common in AS., Results: We found a unique link between neuronal imprinting of Ube3a and circadian rhythms in two mouse models of AS, including enfeebled circadian activity behavior and slowed molecular rhythms in ex vivo brain tissues. As a consequence of compromised circadian behavior, metabolic homeostasis is also disrupted in AS mice. Unsilencing the paternal Ube3a allele restores functional circadian periodicity in neurons deficient in maternal Ube3a but does not affect periodicity in peripheral tissues that are not imprinted for uniparental Ube3a expression. The ubiquitin ligase encoded by Ube3a interacts with the central clock components BMAL1 and BMAL2. Moreover, inactivation of Ube3a expression elevates BMAL1 levels in brain regions that control circadian behavior of AS-model mice, indicating an important role for Ube3a in modulating BMAL1 turnover., Conclusions: Ube3a expression constitutes a direct mechanistic connection between symptoms of a human neurological disorder and the central circadian clock mechanism. The lengthened circadian period leads to delayed phase, which could explain the short sleep duration and increased sleep onset latency of AS subjects. Moreover, we report the pharmacological rescue of an AS phenotype, in this case, altered circadian period. These findings reveal potential treatments for sleep disorders in AS patients., (Copyright © 2015 Elsevier Ltd. All rights reserved.)
- Published
- 2015
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13. Novel BAC Mouse Model of Huntington's Disease with 225 CAG Repeats Exhibits an Early Widespread and Stable Degenerative Phenotype.
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Wegrzynowicz M, Bichell TJ, Soares BD, Loth MK, McGlothan JS, Mori S, Alikhan FS, Hua K, Coughlin JM, Holt HK, Jetter CS, Pomper MG, Osmand AP, Guilarte TR, and Bowman AB
- Subjects
- Animals, Atrophy, Brain metabolism, Chromosomes, Artificial, Bacterial, Disease Models, Animal, Disease Progression, Huntington Disease pathology, Huntington Disease physiopathology, Mice, Inbred C57BL, Mice, Transgenic, Neurons metabolism, Phenotype, Promoter Regions, Genetic, Behavior, Animal, Brain pathology, Huntington Disease genetics, Mice, Neurons pathology, Serotonin Plasma Membrane Transport Proteins genetics, Trinucleotide Repeat Expansion genetics
- Abstract
Background: Unusually large CAG repeat expansions (>60) in exon one of Huntingtin (HTT) are invariably associated with a juvenile-onset form of Huntington's disease (HD), characterized by a more extensive and rapidly progressing neuropathology than the more prevalent adult-onset form. However, existing mouse models of HD that express the full-length Htt gene with CAG repeat lengths associated with juvenile HD (ranging between ~75 to ~150 repeats in published models) exhibit selective neurodegenerative phenotypes more consistent with adult-onset HD. Objective: To determine if a very large CAG repeat (>200) in full-length Htt elicits neurodegenerative phenotypes consistent with juvenile HD., Methods: Using a …bacterial artificial chromosome (BAC) system, we generated mice expressing full-length mouse Htt with ~225 CAG repeats under control of the mouse Htt promoter. Mice were characterized using behavioral, neuropathological, biochemical and brain imaging methods., Results: BAC-225Q mice exhibit phenotypes consistent with a subset of features seen in juvenile-onset HD: very early motor behavior abnormalities, reduced body weight, widespread and progressive increase in Htt aggregates, gliosis, and neurodegeneration. Early striatal pathology was observed, including reactive gliosis and loss of dopamine receptors, prior to detectable volume loss. HD-related blood markers of impaired energy metabolism and systemic inflammation were also increased. Aside from an age-dependent progression of diffuse nuclear aggregates at 6 months of age to abundant neuropil aggregates at 12 months of age, other pathological and motor phenotypes showed little to no progression., Conclusions: The HD phenotypes present in animals 3 to 12 months of age make the BAC-225Q mice a unique and stable model of full-length mutant Htt associated phenotypes, including body weight loss, behavioral impairment and HD-like neurodegenerative phenotypes characteristic of juvenile-onset HD and/or late-stage adult-onset HD.
- Published
- 2015
14. BDNF and Huntingtin protein modifications by manganese: implications for striatal medium spiny neuron pathology in manganese neurotoxicity.
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Stansfield KH, Bichell TJ, Bowman AB, and Guilarte TR
- Subjects
- Animals, Brain cytology, Cells, Cultured, Cerebral Cortex cytology, Disease Models, Animal, Dose-Response Relationship, Drug, Embryo, Mammalian, Gene Expression Regulation drug effects, Huntingtin Protein, Manganese pharmacology, Mice, Microtubule-Associated Proteins metabolism, Phosphorylation drug effects, Rats, Rats, Sprague-Dawley, Brain-Derived Neurotrophic Factor metabolism, Corpus Striatum pathology, Dendritic Spines metabolism, Manganese Poisoning pathology, Nerve Tissue Proteins metabolism, Neurons ultrastructure, Nuclear Proteins metabolism
- Abstract
High levels of manganese (Mn) exposure decrease striatal medium spiny neuron (MSN) dendritic length and spine density, but the mechanism(s) are not known. The Huntingtin (HTT) gene has been functionally linked to cortical brain-derived neurotrophic factor (BDNF) support of striatal MSNs via phosphorylation at serine 421. In Huntington's disease, pathogenic CAG repeat expansions of HTT decrease synthesis and disrupt transport of cortical-striatal BDNF, which may contribute to disease, and Mn is a putative environmental modifier of Huntington's disease pathology. Thus, we tested the hypothesis that changes in MSN dendritic morphology Mn due to exposure are associated with decreased BDNF levels and alterations in Htt protein. We report that BDNF levels are decreased in the striatum of Mn-exposed non-human primates and in the cerebral cortex and striatum of mice exposed to Mn. Furthermore, proBDNF and mature BDNF concentrations in primary cortical and hippocampal neuron cultures were decreased by exposure to Mn confirming the in vivo findings. Mn exposure decreased serine 421 phosphorylation of Htt in cortical and hippocampal neurons and increased total Htt levels. These data strongly support the hypothesis that Mn-exposure-related MSN pathology is associated with decreased BDNF trophic support via alterations in Htt., (© 2014 International Society for Neurochemistry.)
- Published
- 2014
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15. Sleep in children and adolescents with Angelman syndrome: association with parent sleep and stress.
- Author
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Goldman SE, Bichell TJ, Surdyka K, and Malow BA
- Subjects
- Actigraphy, Adolescent, Angelman Syndrome complications, Child, Child, Preschool, Family Health, Female, Humans, Male, Polysomnography, Sleep, Sleep Disorders, Circadian Rhythm etiology, Sleep Initiation and Maintenance Disorders psychology, Stress, Psychological etiology, Surveys and Questionnaires, Angelman Syndrome psychology, Caregivers psychology, Parents psychology, Sleep Disorders, Circadian Rhythm psychology, Stress, Psychological psychology
- Abstract
Background: Sleep concerns are common in children with Angelman syndrome, with 20-80% of individuals having a decreased sleep need and/or abnormal sleep-wake cycles. The impact of these sleep behaviours on parental sleep and stress is not known., Method: Through the use of standardised questionnaires, wrist actigraphy and polysomnography, we defined the sleep behaviours of 15 children/adolescents with Angelman syndrome and the association of the child/adolescents sleep behaviours on parental sleep behaviours and parental stress., Results: Both children/adolescents and their parents exhibited over 1 h of wake time after sleep onset and fragmented sleep. Prolonged sleep latency in the child was associated with parent insomnia and daytime sleepiness. Additionally, variability in child total sleep time was associated with parental stress., Conclusions: Poor sleep in children/adolescents with Angelman syndrome was associated with poor parental sleep and higher parental stress. Further work is warranted to identify the underlying causes of the poor sleep, and to relate these findings to daytime functioning, behaviour and the family unit., (© 2011 The Authors. Journal of Intellectual Disability Research © 2011 Blackwell Publishing Ltd.)
- Published
- 2012
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16. Are children with Angelman syndrome at high risk for anesthetic complications?
- Author
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Landsman IS, Mitzel HM, Peters SU, and Bichell TJ
- Subjects
- Adjuvants, Anesthesia adverse effects, Anesthetics, Intravenous, Angelman Syndrome genetics, Child, Child, Preschool, Critical Care, Female, GABA Agonists adverse effects, Humans, Infant, Intraoperative Complications chemically induced, Intraoperative Complications epidemiology, Length of Stay, Male, Midazolam adverse effects, Phenotype, Propofol adverse effects, Receptors, GABA-A genetics, Retrospective Studies, Risk, Anesthesia adverse effects, Anesthetics adverse effects, Angelman Syndrome complications, Angelman Syndrome epidemiology
- Abstract
Objectives/aims: To review seven children with Angelman syndrome (AS) undergoing 16 general anesthetics for both invasive and noninvasive procedures to determine if these children are at greater risk for anesthetic-related complications than the general population., Background: Children with AS may exhibit unpredictable responses to GABA agonists because of abnormal GABA receptors. These abnormal receptors may affect AS patients' responses to sedation and general anesthesia., Methods: The study design was a retrospective chart review of seven patients with AS who underwent a total of 16 general anesthetics for a variety of invasive and noninvasive procedures between the years 4/25/2005 and 12/31/2010. We reviewed the preoperative orders, anesthesia record and PACU records for preoperative medication orders and intraoperative and PACU adverse events., Results: We could not find documentation of complications attributed to the delivery of general anesthesia regardless of chromosomal defect, the use of GABA activating drugs, or a history of seizures. Six patients received a propofol-based anesthetic while 10 patients received potent inhalation agent for anesthetic maintenance. There were no statistical differences between the PACU lengths of stay (LOS) for AS patients as compared to the average PACU LOS for the 60 969 postprocedure patients cared for between 1/1/06 through 12/31/10., Conclusions: We found no data to suggest that these patients demonstrate exaggerated responses to GABA stimulating drugs. In fact, it appears that regardless of the anesthetic agent, the perioperative course was unremarkable., (© 2011 Blackwell Publishing Ltd.)
- Published
- 2012
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17. Angelman syndrome: Mutations influence features in early childhood.
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Tan WH, Bacino CA, Skinner SA, Anselm I, Barbieri-Welge R, Bauer-Carlin A, Beaudet AL, Bichell TJ, Gentile JK, Glaze DG, Horowitz LT, Kothare SV, Lee HS, Nespeca MP, Peters SU, Sahoo T, Sarco D, Waisbren SE, and Bird LM
- Subjects
- Child, Preschool, Data Collection, Electroencephalography, Humans, Infant, Longitudinal Studies, Mutation genetics, Statistics, Nonparametric, Angelman Syndrome genetics, Angelman Syndrome pathology, Chromosome Aberrations, Chromosomes, Human, Pair 15 genetics, Phenotype, Ubiquitin-Protein Ligases genetics
- Abstract
Angelman syndrome (AS) is a neurodevelopmental disorder caused by a lack of expression of the maternal copy of UBE3A. Although the "classic" features of AS are well described, few large-scale studies have delineated the clinical features in AS. We present baseline data from 92 children with a molecular diagnosis of AS between 5 and 60 months old who are enrolled in the National Institutes of Health Rare Diseases Clinical Research Network Angelman Syndrome Natural History Study from January 2006 to March 2008. Seventy-four percent of participants had deletions, 14% had either uniparental disomy (UPD) or imprinting defects, and 12% had UBE3A mutations. Participants with UPD/imprinting defects were heavier (P = 0.0002), while those with deletions were lighter, than the general population (P < 0.0001). Twenty out of 92 participants were underweight, all of whom had deletions or UBE3A mutations. Eight out of 92 participants (6/13 (46%) with UPD/imprinting defects and 2/11 (18%) with UBE3A mutations) were obese. Seventy-four out of 92 participants (80%) had absolute or relative microcephaly. No participant was macrocephalic. The most common behavioral findings were mouthing behavior (95%), short attention span (92%), ataxic or broad-based gait (88%), history of sleep difficulties (80%), and fascination with water (75%). Frequent, easily provoked laughter was observed in 60%. Clinical seizures were reported in 65% of participants but all electroencephalograms (EEGs) were abnormal. We conclude that the most characteristic feature of AS is the neurobehavioral phenotype, but specific EEG findings are highly sensitive for AS. Obesity is common among those with UPD/imprinting defects., (Copyright © 2010 Wiley-Liss, Inc.)
- Published
- 2011
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18. Tissue-specific variation of Ube3a protein expression in rodents and in a mouse model of Angelman syndrome.
- Author
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Gustin RM, Bichell TJ, Bubser M, Daily J, Filonova I, Mrelashvili D, Deutch AY, Colbran RJ, Weeber EJ, and Haas KF
- Subjects
- Analysis of Variance, Angelman Syndrome genetics, Animals, Blotting, Western, Disease Models, Animal, Immunohistochemistry, Mice, Mice, Knockout, Neurons metabolism, Tissue Distribution, Ubiquitin-Protein Ligases genetics, gamma-Aminobutyric Acid metabolism, Angelman Syndrome metabolism, Brain metabolism, Liver metabolism, Myocardium metabolism, Ubiquitin-Protein Ligases metabolism
- Abstract
Angelman syndrome (AS) is a neurogenetic disorder caused by loss of maternal UBE3A expression or mutation-induced dysfunction of its protein product, the E3 ubiquitin-protein ligase, UBE3A. In humans and rodents, UBE3A/Ube3a transcript is maternally imprinted in several brain regions, but the distribution of native UBE3A/Ube3a(1) protein expression has not been comprehensively examined. To address this, we systematically evaluated Ube3a expression in the brain and peripheral tissues of wild-type (WT) and Ube3a maternal knockout mice (AS mice). Immunoblot and immunohistochemical analyses revealed a marked loss of Ube3a protein in hippocampus, hypothalamus, olfactory bulb, cerebral cortex, striatum, thalamus, midbrain, and cerebellum in AS mice relative to WT littermates. Also, Ube3a expression in heart and liver of AS mice showed greater than the predicted 50% reduction relative to WT mice. Co-localization studies showed Ube3a expression to be primarily neuronal in all brain regions and present in GABAergic interneurons as well as principal neurons. These findings suggest that neuronal function throughout the brain is compromised in AS.
- Published
- 2010
- Full Text
- View/download PDF
19. Double-blind therapeutic trial in Angelman syndrome using betaine and folic acid.
- Author
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Peters SU, Bird LM, Kimonis V, Glaze DG, Shinawi LM, Bichell TJ, Barbieri-Welge R, Nespeca M, Anselm I, Waisbren S, Sanborn E, Sun Q, O'Brien WE, Beaudet AL, and Bacino CA
- Subjects
- Adolescent, Angelman Syndrome genetics, Angelman Syndrome pathology, Child, Child, Preschool, Chromosomes, Human, Pair 15 genetics, DNA Methylation, Double-Blind Method, Drug Combinations, Female, Genomic Imprinting, Humans, Infant, Lipotropic Agents therapeutic use, Male, Phenotype, Placebos, Ubiquitin-Protein Ligases genetics, Vitamin B Complex therapeutic use, Angelman Syndrome drug therapy, Betaine therapeutic use, Folic Acid therapeutic use
- Abstract
Angelman syndrome (AS) is caused by reduced or absent expression of the maternally inherited ubiquitin protein ligase 3A gene (UBE3A), which maps to chromosome 15q11-q13. UBE3A is subject to genomic imprinting in neurons in most regions of the brain. Expression of UBE3A from the maternal chromosome is essential to prevent AS, because the paternally inherited gene is not expressed, probably mediated by antisense UBE3A RNA. We hypothesized that increasing methylation might reduce expression of the antisense UBE3A RNA, thereby increasing UBE3A expression from the paternal gene and ameliorating the clinical phenotype. We conducted a trial using two dietary supplements, betaine and folic acid to promote global levels of methylation and attempt to activate the paternally inherited UBE3A gene. We performed a number of investigations at regular intervals including general clinical and developmental evaluations, biochemical determinations on blood and urine, and electroencephalographic studies. We report herein the data on 48 children with AS who were enrolled in a double-blind placebo-controlled protocol using betaine and folic acid for 1 year. There were no statistically significant changes between treated and untreated children; however, in a small subset of patients we observed some positive trends.
- Published
- 2010
- Full Text
- View/download PDF
20. Microarray based comparative genomic hybridization testing in deletion bearing patients with Angelman syndrome: genotype-phenotype correlations.
- Author
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Sahoo T, Peters SU, Madduri NS, Glaze DG, German JR, Bird LM, Barbieri-Welge R, Bichell TJ, Beaudet AL, and Bacino CA
- Subjects
- Angelman Syndrome genetics, Autistic Disorder diagnosis, Autistic Disorder genetics, Base Sequence, Child, Child, Preschool, Chromosomes, Human, Pair 15, Female, Genetic Testing methods, Genotype, Humans, Infant, Male, Phenotype, Seizures diagnosis, Seizures genetics, Angelman Syndrome diagnosis, Oligonucleotide Array Sequence Analysis methods, Sequence Deletion
- Abstract
Background: Angelman syndrome (AS) is a neurodevelopmental disorder characterised by severe mental retardation, dysmorphic features, ataxia, seizures, and typical behavioural characteristics, including a happy sociable disposition. AS is caused by maternal deficiency of UBE3A (E6 associated protein ubiquitin protein ligase 3A gene), located in an imprinted region on chromosome 15q11-q13. Although there are four different molecular types of AS, deletions of the 15q11-q13 region account for approximately 70% of the AS patients. These deletions are usually detected by fluorescence in situ hybridisation studies. The deletions can also be subclassified based on their size into class I and class II, with the former being larger and encompassing the latter., Methods: We studied 22 patients with AS due to microdeletions using a microarray based comparative genomic hybridisation (array CGH) assay to define the deletions and analysed their phenotypic severity, especially expression of the autism phenotype, in order to establish clinical correlations., Results: Overall, children with larger, class I deletions were significantly more likely to meet criteria for autism, had lower cognitive scores, and lower expressive language scores compared with children with smaller, class II deletions. Children with class I deletions also required more medications to control their seizures than did those in the class II group., Conclusions: There are four known genes (NIPA1, NIPA2, CYFIP1, & GCP5) that are affected by class I but not class II deletions, thus raising the possibility of a role for these genes in autism as well as the development of expressive language skills.
- Published
- 2006
- Full Text
- View/download PDF
21. Population-based needs assessment. Bringing public health to midwifery practice.
- Author
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Declercq ER, Bichell TJ, and Center JK
- Subjects
- Data Collection methods, Female, Humans, Pregnancy, Research Design, Health Services Needs and Demand, Health Services Research methods, Maternal Health Services, Midwifery
- Abstract
Midwives are accustomed to individualizing their care of women on the basis of an assessment of each client's health status. By expanding their focus of care to encompass treatment of a population group, midwives and other providers can adopt a public health perspective through use of a community needs assessment. The first steps in diagnosing and treating the health problems of a group require the same rigorous and systematic examination of health indicators as does treatment of an individual. This article outlines the needs assessment process, identifies basic sources of information, and describes ways in which results can be presented.
- Published
- 1997
- Full Text
- View/download PDF
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