38 results on '"Yohay K"'
Search Results
2. The Life Span of New Neurons in a Song Control Nucleus of the Adult Canary Brain Depends on Time of Year when these Cells are Born
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Nottebohm, F., O'Loughlin, B., Gould, K., Yohay, K., and Alvarez-Buylla, A.
- Published
- 1994
3. Vascular Distribution of Glioblastoma Multiforme at Diagnosis.
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YOHAY, K., WOLF, D. S., ARONSON, L. J., DUUS, M., MELHEM, E. R., and COHEN, K. J.
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GLIOMA treatment , *MEDICAL imaging systems , *CANCER chemotherapy , *NERVOUS system tumors , *NEUROBLASTOMA , *TUMOR treatment , *THERAPEUTICS - Abstract
Treatment of high-grade gliomas with selective intra-arterial (IA) administration of chemotherapies has been proposed, and utilized as a therapeutic modality. This approach offers the conceptual benefit of providing maximal delivery of the agent to the tumor bed, while potentially reducing systemic exposure to the agent. This retrospective study was designed to determine the vascular distribution of glioblastoma multiforme (GBM) at the time of diagnosis in an effort to determine what proportion of patients would likely be candidates for this approach. The preoperative MRI scans of 50 patients with GBM were analyzed and compared to published normative data of intracranial vascular distribution. Vascular distribution was determined by analyzing post-gadolinium axial and coronal T1 images, axial T2 images, and axial T2 images with an additional 1 cm margin (T2 + 1 cm) added in all dimensions. T1 analysis demonstrated 60% of tumors in a single vascular distribution. T2 analysis of these tumors reduced that number to 34%. When the T2 + 1 cm margin was utilized, only 6% of tumors were in a single vascular distribution. 66% of tumors were limited to the anterior circulation on T1 imaging but only 34% on T2 + 1 cm imaging. 30% of tumors were also within the distribution of the anterior choroidal artery. These findings suggest that the use of selective IA administration of agents is necessarily limited to a fraction of presenting patients or will require administration via multiple cerebral arteries. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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4. Identifying Lesions of the Corpus Callosum in Patients With Neurofibromatosis Type 1.
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Jandhyala NR, Garcia MR, Kim M, Yohay K, and Segal D
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- Humans, Child, Child, Preschool, Adolescent, Male, Female, Infant, Adult, Young Adult, Middle Aged, Aged, Aged, 80 and over, Retrospective Studies, Neurofibromatosis 1 diagnostic imaging, Neurofibromatosis 1 complications, Neurofibromatosis 1 pathology, Corpus Callosum diagnostic imaging, Corpus Callosum pathology, Magnetic Resonance Imaging, Glioma diagnostic imaging, Glioma pathology, Brain Neoplasms diagnostic imaging, Brain Neoplasms pathology, Brain Neoplasms complications
- Abstract
Background: Neurofibromatosis type 1 (NF1) is a multisystemic autosomal dominant disorder that includes intracranial lesions such as unidentified bright objects (UBOs)-areas of increased T2 signal on magnetic resonance imaging (MRI)-and tumors known as gliomas. The presence of these lesions in the corpus callosum (CC) has not been previously studied in a large cohort., Methods: We reviewed medical records of 681 patients (aged three months to 86 years) followed at our institution from 2000 to 2023 with NF1 and one or more brain MRI. Patients with lesions in the CC were identified, and RAPNO/RANO criteria were used to determine changes in size over time, where a change of 25% in the product of perpendicular measurements indicates growth or shrinkage., Results: Forty-seven patients had CC UBOs, most of which were in the splenium (66.0%). Seventeen patients had CC gliomas (10% of those with any glioma), two of whom had two gliomas. Seventeen of 19 gliomas were in the splenium. Over follow-up, eight of 19 remained stable, three shrunk, and eight grew. The mean percentage change in the product of the dimensions was 311.5% (ranging from -46.7% to 2566.6%). Of the eight lesions that grew, one required treatment., Conclusions: There is a 6.9% and 2.5% prevalence of CC UBOs and gliomas, respectively, in our cohort of patients with NF1. Most lesions are present in the splenium, and although some gliomas demonstrate significant growth, they rarely require treatment. This work is the largest series of CC lesions in NF1 and adds to the growing data to inform appropriate follow-up., Competing Interests: Declaration of competing interest Nora R Jandhyala, Mekka R Garcia, and Monica Kim have no conflicts of interest to declare. Devorah Segal has served on the medical advisory board for Alexion, June 2023. Kaleb Yohay acts as a consultant for Alexion and serves on the scientific advisory boards for Infixion Bioscience and NF2 Biosolutions., (Copyright © 2024 Elsevier Inc. All rights reserved.)
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- 2024
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5. Endoglin, a Novel Biomarker and Therapeutical Target to Prevent Malignant Peripheral Nerve Sheath Tumor Growth and Metastasis.
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González-Muñoz T, Di Giannatale A, García-Silva S, Santos V, Sánchez-Redondo S, Savini C, Graña-Castro O, Blanco-Aparicio C, Fischer S, De Wever O, Creus-Bachiller E, Ortega-Bertran S, Pisapia DJ, Rodríguez-Peralto JL, Fernández-Rodríguez J, Pérez-Portabella CR, Alaggio R, Benassi MS, Pazzaglia L, Scotlandi K, Ratner N, Yohay K, Theuer CP, and Peinado H
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- Humans, Biomarkers, Cell Line, Tumor, Endoglin genetics, Mitogen-Activated Protein Kinase Kinases metabolism, Signal Transduction, Nerve Sheath Neoplasms drug therapy, Nerve Sheath Neoplasms genetics, Nerve Sheath Neoplasms metabolism, Neurofibrosarcoma
- Abstract
Purpose: Malignant peripheral nerve sheath tumors (MPNST) are highly aggressive soft-tissue sarcomas that lack effective treatments, underscoring the urgent need to uncover novel mediators of MPNST pathogenesis that may serve as potential therapeutic targets. Tumor angiogenesis is considered a critical event in MPNST transformation and progression. Here, we have investigated whether endoglin (ENG), a TGFβ coreceptor with a crucial role in angiogenesis, could be a novel therapeutic target in MPNSTs., Experimental Design: ENG expression was evaluated in human peripheral nerve sheath tumor tissues and plasma samples. Effects of tumor cell-specific ENG expression on gene expression, signaling pathway activation and in vivo MPNST growth and metastasis, were investigated. The efficacy of ENG targeting in monotherapy or in combination with MEK inhibition was analyzed in xenograft models., Results: ENG expression was found to be upregulated in both human MPNST tumor tissues and plasma-circulating small extracellular vesicles. We demonstrated that ENG modulates Smad1/5 and MAPK/ERK pathway activation and pro-angiogenic and pro-metastatic gene expression in MPNST cells and plays an active role in tumor growth and metastasis in vivo. Targeting with ENG-neutralizing antibodies (TRC105/M1043) decreased MPNST growth and metastasis in xenograft models by reducing tumor cell proliferation and angiogenesis. Moreover, combination of anti-ENG therapy with MEK inhibition effectively reduced tumor cell growth and angiogenesis., Conclusions: Our data unveil a tumor-promoting function of ENG in MPNSTs and support the use of this protein as a novel biomarker and a promising therapeutic target for this disease., (©2023 American Association for Cancer Research.)
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- 2023
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6. Management of neurofibromatosis type 1-associated plexiform neurofibromas.
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Fisher MJ, Blakeley JO, Weiss BD, Dombi E, Ahlawat S, Akshintala S, Belzberg AJ, Bornhorst M, Bredella MA, Cai W, Ferner RE, Gross AM, Harris GJ, Listernick R, Ly I, Martin S, Mautner VF, Salamon JM, Salerno KE, Spinner RJ, Staedtke V, Ullrich NJ, Upadhyaya M, Wolters PL, Yohay K, and Widemann BC
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- Humans, Protein Kinase Inhibitors, Neurofibroma, Plexiform pathology, Neurofibromatosis 1 pathology, Nerve Sheath Neoplasms
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Plexiform Neurofibromas (PN) are a common manifestation of the genetic disorder neurofibromatosis type 1 (NF1). These benign nerve sheath tumors often cause significant morbidity, with treatment options limited historically to surgery. There have been tremendous advances over the past two decades in our understanding of PN, and the recent regulatory approvals of the MEK inhibitor selumetinib are reshaping the landscape for PN management. At present, there is no agreed upon PN definition, diagnostic evaluation, surveillance strategy, or clear indications for when to initiate treatment and selection of treatment modality. In this review, we address these questions via consensus recommendations from a panel of multidisciplinary NF1 experts., (Published by Oxford University Press on behalf of the Society for Neuro-Oncology 2022.)
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- 2022
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7. MEK inhibitors for neurofibromatosis type 1 manifestations: Clinical evidence and consensus.
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de Blank PMK, Gross AM, Akshintala S, Blakeley JO, Bollag G, Cannon A, Dombi E, Fangusaro J, Gelb BD, Hargrave D, Kim A, Klesse LJ, Loh M, Martin S, Moertel C, Packer R, Payne JM, Rauen KA, Rios JJ, Robison N, Schorry EK, Shannon K, Stevenson DA, Stieglitz E, Ullrich NJ, Walsh KS, Weiss BD, Wolters PL, Yohay K, Yohe ME, Widemann BC, and Fisher MJ
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- Child, Humans, Consensus, Mitogen-Activated Protein Kinase Kinases antagonists & inhibitors, Neurofibroma, Plexiform drug therapy, Neurofibromatosis 1 drug therapy, Neurofibromatosis 1 pathology, Protein Kinase Inhibitors pharmacology
- Abstract
The wide variety of clinical manifestations of the genetic syndrome neurofibromatosis type 1 (NF1) are driven by overactivation of the RAS pathway. Mitogen-activated protein kinase kinase inhibitors (MEKi) block downstream targets of RAS. The recent regulatory approvals of the MEKi selumetinib for inoperable symptomatic plexiform neurofibromas in children with NF1 have made it the first medical therapy approved for this indication in the United States, the European Union, and elsewhere. Several recently published and ongoing clinical trials have demonstrated that MEKi may have potential benefits for a variety of other NF1 manifestations, and there is broad interest in the field regarding the appropriate clinical use of these agents. In this review, we present the current evidence regarding the use of existing MEKi for a variety of NF1-related manifestations, including tumor (neurofibromas, malignant peripheral nerve sheath tumors, low-grade glioma, and juvenile myelomonocytic leukemia) and non-tumor (bone, pain, and neurocognitive) manifestations. We discuss the potential utility of MEKi in related genetic conditions characterized by overactivation of the RAS pathway (RASopathies). In addition, we review practical treatment considerations for the use of MEKi as well as provide consensus recommendations regarding their clinical use from a panel of experts., (Published by Oxford University Press on behalf of the Society for Neuro-Oncology 2022.)
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- 2022
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8. Updated diagnostic criteria and nomenclature for neurofibromatosis type 2 and schwannomatosis: An international consensus recommendation.
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Plotkin SR, Messiaen L, Legius E, Pancza P, Avery RA, Blakeley JO, Babovic-Vuksanovic D, Ferner R, Fisher MJ, Friedman JM, Giovannini M, Gutmann DH, Hanemann CO, Kalamarides M, Kehrer-Sawatzki H, Korf BR, Mautner VF, MacCollin M, Papi L, Rauen KA, Riccardi V, Schorry E, Smith MJ, Stemmer-Rachamimov A, Stevenson DA, Ullrich NJ, Viskochil D, Wimmer K, Yohay K, Huson SM, Wolkenstein P, and Evans DG
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- Consensus, Humans, Neurilemmoma diagnosis, Neurilemmoma genetics, Neurilemmoma pathology, Neurofibromatoses diagnosis, Neurofibromatoses genetics, Neurofibromatosis 1 genetics, Neurofibromatosis 2 diagnosis, Neurofibromatosis 2 genetics, Skin Neoplasms genetics
- Abstract
Purpose: Neurofibromatosis type 2 (NF2) and schwannomatosis (SWN) are genetically distinct tumor predisposition syndromes with overlapping phenotypes. We sought to update the diagnostic criteria for NF2 and SWN by incorporating recent advances in genetics, ophthalmology, neuropathology, and neuroimaging., Methods: We used a multistep process, beginning with a Delphi method involving global disease experts and subsequently involving non-neurofibromatosis clinical experts, patients, and foundations/patient advocacy groups., Results: We reached consensus on the minimal clinical and genetic criteria for diagnosing NF2 and SWN. These criteria incorporate mosaic forms of these conditions. In addition, we recommend updated nomenclature for these disorders to emphasize their phenotypic overlap and to minimize misdiagnosis with neurofibromatosis type 1., Conclusion: The updated criteria for NF2 and SWN incorporate clinical features and genetic testing, with a focus on using molecular data to differentiate the 2 conditions. It is likely that continued refinement of these new criteria will be necessary as investigators study the diagnostic properties of the revised criteria and identify new genes associated with SWN. In the revised nomenclature, the term "neurofibromatosis 2" has been retired to improve diagnostic specificity., Competing Interests: Conflict of Interest R.A.A., C.O.H., and K.A.R declare no conflicts of interest. D.B.-V. is a scientific advisor for AstraZeneca, L.P. and receives grant support from the Department of Defense and SpringWorks Therapeutics. J.B. is a member of the Children’s Tumor Foundation Medical Advisory Committee and the Clinical Care Advisory Board. D.G.E. is a member of the Children’s Tumor Foundation Clinical Care Advisory Board-Europe and has received consultancy fees from AstraZeneca, SpringWorks Therapeutics, and Recursion. R.F. is a member of the Children’s Tumor Foundation Clinical Care Advisory Board-Europe and is a medical advisor for AstraZeneca. M.J.F. is a member of the Children’s Tumor Foundation Medical Advisory Committee. J.M.F. is a member of the Children’s Tumor Foundation Clinical Care Advisory Board. M.G. receives grant support from NF2 Therapeutics, Inc and is a consultant for Puma Biotechnology. D.H.G. declares no conflicts of interest. M.K. is a paid consultant for Regeneron Pharmaceuticals. S.M.H. declares no conflicts of interest. H.K.-S. declares no conflicts of interest. B.R.K is a member of the Children’s Tumor Foundation Medical Advisory Committee (Chair) and is on the medical advisory boards of Genome Medicine and iNfixion Bioscience. E.L. is a member of the Children’s Tumor Foundation Clinical Care Advisory Board-Europe. V.-F.M. is a member of the Children’s Tumor Foundation Clinical Care Advisory Board-Europe. M.M. declares no conflicts of interest. L.P. declares no conflicts of interest. L.M. directed the Medical Genomics Laboratory at University of Alabama, Birmingham, which specializes in genetic testing for all forms of the neurofibromatosis, until April 2021. P.P. is employed by the Children’s Tumor Foundation. S.R.P is a member of the Children’s Tumor Foundation Clinical Care Advisory Board (Chair, United States) and Europe; is cofounder of NFlection Therapeutics, Inc and NF2 Therapeutics, Inc; and is a consultant for Akouos, AstraZeneca, and SonALASense. V.R. declares no conflicts of interest. E.S. is a member of the Children’s Tumor Foundation Clinical Care Advisory Board and receives Department of Defense funding as a site for NF Clinical Trials Consortium. M.J.S declares no conflicts of interest. A.S.-R. declares no conflicts of interest. D.A.S. is a consultant for Alexion Pharmaceuticals, Inc. N.J.U is a member of the Children’s Tumor Foundation Clinical Care Advisory Board, serves on the board of Neurofibromatosis Northeast, and received a consultant fee from Astra Zeneca. D.V. is a member of the Children’s Tumor Foundation Medical Advisory Committee and Clinical Care Advisory Board, is a member of the AstraZeneca speaker’s bureau, and is on the Sanofi-Genzyme—MPS Board of Advisors. K.W. declares no conflicts of interest. P.W. is a member of the Children’s Tumor Foundation Clinical Care Advisory Board-Europe (Chair). K.Y. is a member of the Children’s Tumor Foundation Clinical Care Advisory Board, received a consultant fee from AstraZeneca, is on the Scientific Advisory Board for iNFixion Bioscience, is member of the Programmatic Review Committee for the Department of Defense, Congressionally Directed Medical Research Program, and Neurofibromatosis Research Program., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2022
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9. Management and surgical outcomes of dystrophic scoliosis in neurofibromatosis type 1: a systematic review.
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Neifert SN, Khan HA, Kurland DB, Kim NC, Yohay K, Segal D, Samdani A, Hwang S, and Lau D
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- Adolescent, Adult, Child, Humans, Multicenter Studies as Topic, Postoperative Complications, Prospective Studies, Retrospective Studies, Thoracic Vertebrae surgery, Treatment Outcome, Young Adult, Neurofibromatosis 1 complications, Neurofibromatosis 1 diagnostic imaging, Neurofibromatosis 1 surgery, Scoliosis complications, Scoliosis diagnostic imaging, Scoliosis surgery, Spinal Fusion methods
- Abstract
Objective: Neurofibromatosis type 1 (NF1) dystrophic scoliosis is an early-onset, rapidly progressive multiplanar deformity. There are few studies on the surgical management of this patient population. Specifically, perioperative morbidity, instrument-related complications, and quality-of-life outcomes associated with surgical management have not been systematically evaluated. In this study, the authors aimed to perform a systematic review on the natural history, management options, and surgical outcomes in patients who underwent NF1 dystrophic scoliosis surgery., Methods: A PubMed search for articles with "neurofibromatosis" and either "dystrophic" or "scoliosis" in the title or abstract was performed. Articles with 10 or more patients undergoing surgery for NF1 dystrophic scoliosis were included. Data regarding indications, treatment details, morbidity, and outcomes were summarized and analyzed with descriptive statistics., Results: A total of 310 articles were identified, 48 of which were selected for full-text review; 30 studies describing 761 patients met the inclusion criteria. The mean age ranged from 7 to 22 years, and 99.7% of patients were younger than 18 years. The mean preoperative coronal Cobb angle was 75.2°, and the average correction achieved was 40.3°. The mean clinical follow-up in each study was at least 2 years (range 2.2-19 years). All patients underwent surgery with the intent of deformity correction. The scoliosis regions addressed were thoracic curves (69.6%) and thoracolumbar (11.1%) and lumbar (14.3%) regions. The authors reported on a variety of approaches: posterior-only, combined anterior-posterior, and growth-friendly surgery. For fixation techniques, 42.5% of patients were treated with hybrid constructs, 51.5% with pedicle screw-only constructs, and 6.0% with hook-based constructs. Only 0.9% of patients underwent a vertebral column resection. The nonneurological complication rate was 14.0%, primarily dural tears and wound infections. The immediate postoperative neurological deficit rate was 2.1%, and the permanent neurological deficit rate was 1.2%. Ultimately, 21.5% required revision surgery, most commonly for implant-related complications. Loss of correction in both the sagittal and coronal planes commonly occurred at follow-up. Five papers supplied validated patient-reported outcome measures, showing improvement in the mental health, self-image, and activity domains., Conclusions: Data on the surgical outcomes of dystrophic scoliosis correction are heterogeneous and sparse. The perioperative complication rate appears to be high, although reported rates of neurological deficits appear to be lower than clinically observed and may be underreported. The incidence of implant-related failures requiring revision surgery is high. There is a great need for multicenter prospective studies of this complex type of deformity.
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- 2022
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10. Awareness and agreement with neurofibromatosis care guidelines among U.S. neurofibromatosis specialists.
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Merker VL, Knight P, Radtke HB, Yohay K, Ullrich NJ, Plotkin SR, and Jordan JT
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- Cross-Sectional Studies, Female, Humans, Male, Quality Improvement, Rare Diseases, United States, Neurofibromatoses, Neurofibromatosis 1 pathology
- Abstract
Introduction: The neurofibromatoses (NF) are a group of rare, genetic diseases sharing a predisposition to develop multiple benign nervous system tumors. Given the wide range of NF symptoms and medical specialties involved in NF care, we sought to evaluate the level of awareness of, and agreement with, published NF clinical guidelines among NF specialists in the United States., Methods: An anonymous, cross-sectional, online survey was distributed to U.S.-based NF clinicians. Respondents self-reported demographics, practice characteristics, awareness of seven NF guideline publications, and level of agreement with up to 40 individual recommendations using a 5-point Likert scale. We calculated the proportion of recommendations that each clinician rated "strongly agree", and assessed for differences in guideline awareness and agreement by respondent characteristics., Results: Sixty-three clinicians (49% female; 80% academic practice) across > 8 medical specialties completed the survey. Awareness of each guideline publication ranged from 53%-79% of respondents; specialists had higher awareness of publications endorsed by their medical professional organization (p < 0.05). The proportion of respondents who "strongly agree" with individual recommendations ranged from 17%-83%; for 16 guidelines, less than 50% of respondents "strongly agree". There were no significant differences in overall agreement with recommendations based on clinicians' gender, race, specialty, years in practice, practice type (academic/private practice/other), practice location (urban/suburban/rural), or involvement in NF research (p > 0.05 for all)., Conclusions: We identified wide variability in both awareness of, and agreement with, published NF care guidelines among NF experts. Future quality improvement efforts should focus on evidence-based, consensus-driven methods to update and disseminate guidelines across this multi-specialty group of providers. Patients and caregivers should also be consulted to proactively anticipate barriers to accessing and implementing guideline-driven care. These recommendations for improving guideline knowledge and adoption may also be useful for other rare diseases requiring multi-specialty care coordination., (© 2022. The Author(s).)
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- 2022
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11. Reliability of Handheld Dynamometry to Measure Focal Muscle Weakness in Neurofibromatosis Types 1 and 2.
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Akshintala S, Khalil N, Yohay K, Muzikansky A, Allen J, Yaffe A, Gross AM, Fisher MJ, Blakeley JO, Oberlander B, Pudel M, Engelson C, Obletz J, Mitchell C, Widemann BC, Stevenson DA, and Plotkin SR
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- Adolescent, Adult, Child, Humans, Male, Middle Aged, Muscle Strength Dynamometer, Muscle Weakness diagnosis, Neurofibromatoses physiopathology, Isometric Contraction physiology, Muscle Strength physiology, Muscle Weakness physiopathology, Muscle, Skeletal physiology
- Abstract
Objective: To determine a suitable outcome measure for assessing muscle strength in neurofibromatosis (NF) type 1 and NF2 clinical trials, we evaluated the intraobserver reliability of handheld dynamometry (HHD) and developed consensus recommendations for its use in NF clinical trials., Methods: Patients ≥5 years of age with weakness in at least 1 muscle group by manual muscle testing (MMT) were eligible. Maximal isometric muscle strength of a weak muscle group and the biceps of the dominant arm was measured by HHD. An average of 3 repetitions per session was used as an observation, and 3 sessions with rest period between each were performed on the same day by a single observer. Intrasession and intersession intraclass correlation coefficients (ICCs) and coefficients of variation (CVs) were calculated to assess reliability and measurement error., Results: Twenty patients with NF1 and 13 with NF2 were enrolled; median age was 12 years (interquartile range [IQR] 9-17 years) and 29 years (IQR 22-38 years), respectively. By MMT, weak muscle strength ranged from 2-/5 to 4+/5. Biceps strength was 5/5 in all patients. Intersession ICCs for the weak muscles were 0.98 and 0.99 in the NF1 and NF2 cohorts, respectively, and for biceps were 0.97 and 0.97, respectively. The median CVs for average session strength were 5.4% (IQR 2.6%-7.3%) and 2.9% (IQR 2.0%-6.2%) for weak muscles and biceps, respectively., Conclusion: HHD performed by a trained examiner with a well-defined protocol is a reliable technique to measure muscle strength in NF1 and NF2. Recommendations for strength testing in NF1 and NF2 trials are provided., (© 2021 American Academy of Neurology.)
- Published
- 2021
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12. Revised diagnostic criteria for neurofibromatosis type 1 and Legius syndrome: an international consensus recommendation.
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Legius E, Messiaen L, Wolkenstein P, Pancza P, Avery RA, Berman Y, Blakeley J, Babovic-Vuksanovic D, Cunha KS, Ferner R, Fisher MJ, Friedman JM, Gutmann DH, Kehrer-Sawatzki H, Korf BR, Mautner VF, Peltonen S, Rauen KA, Riccardi V, Schorry E, Stemmer-Rachamimov A, Stevenson DA, Tadini G, Ullrich NJ, Viskochil D, Wimmer K, Yohay K, Huson SM, Evans DG, and Plotkin SR
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- Cafe-au-Lait Spots genetics, Consensus, Genetic Testing, Humans, Neurofibromatosis 1 diagnosis, Neurofibromatosis 1 genetics
- Abstract
Purpose: By incorporating major developments in genetics, ophthalmology, dermatology, and neuroimaging, to revise the diagnostic criteria for neurofibromatosis type 1 (NF1) and to establish diagnostic criteria for Legius syndrome (LGSS)., Methods: We used a multistep process, beginning with a Delphi method involving global experts and subsequently involving non-NF experts, patients, and foundations/patient advocacy groups., Results: We reached consensus on the minimal clinical and genetic criteria for diagnosing and differentiating NF1 and LGSS, which have phenotypic overlap in young patients with pigmentary findings. Criteria for the mosaic forms of these conditions are also recommended., Conclusion: The revised criteria for NF1 incorporate new clinical features and genetic testing, whereas the criteria for LGSS were created to differentiate the two conditions. It is likely that continued refinement of these new criteria will be necessary as investigators (1) study the diagnostic properties of the revised criteria, (2) reconsider criteria not included in this process, and (3) identify new clinical and other features of these conditions. For this reason, we propose an initiative to update periodically the diagnostic criteria for NF1 and LGSS., (© 2021. The Author(s).)
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- 2021
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13. Slowing late infantile Batten disease by direct brain parenchymal administration of a rh.10 adeno-associated virus expressing CLN2 .
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Sondhi D, Kaminsky SM, Hackett NR, Pagovich OE, Rosenberg JB, De BP, Chen A, Van de Graaf B, Mezey JG, Mammen GW, Mancenido D, Xu F, Kosofsky B, Yohay K, Worgall S, Kaner RJ, Souwedaine M, Greenwald BM, Kaplitt M, Dyke JP, Ballon DJ, Heier LA, Kiss S, and Crystal RG
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- Aminopeptidases genetics, Brain, Child, Dipeptidyl-Peptidases and Tripeptidyl-Peptidases genetics, Genetic Therapy, Humans, Magnetic Resonance Imaging, Tripeptidyl-Peptidase 1, Dependovirus genetics, Neuronal Ceroid-Lipofuscinoses genetics, Neuronal Ceroid-Lipofuscinoses therapy
- Abstract
Late infantile Batten disease (CLN2 disease) is an autosomal recessive, neurodegenerative lysosomal storage disease caused by mutations in the CLN2 gene encoding tripeptidyl peptidase 1 (TPP1). We tested intraparenchymal delivery of AAVrh.10hCLN2, a nonhuman serotype rh.10 adeno-associated virus vector encoding human CLN2 , in a nonrandomized trial consisting of two arms assessed over 18 months: AAVrh.10hCLN2-treated cohort of 8 children with mild to moderate disease and an untreated, Weill Cornell natural history cohort consisting of 12 children. The treated cohort was also compared to an untreated European natural history cohort of CLN2 disease. The vector was administered through six burr holes directly to 12 sites in the brain without immunosuppression. In an additional safety assessment under a separate protocol, five children with severe CLN2 disease were treated with AAVrh.10hCLN2. The therapy was associated with a variety of expected adverse events, none causing long-term disability. Induction of systemic anti-AAVrh.10 immunity was mild. After therapy, the treated cohort had a 1.3- to 2.6-fold increase in cerebral spinal fluid TPP1. There was a slower loss of gray matter volume in four of seven children by MRI and a 42.4 and 47.5% reduction in the rate of decline of motor and language function, compared to Weill Cornell natural history cohort ( P < 0.04) and European natural history cohort ( P < 0.0001), respectively. Intraparenchymal brain administration of AAVrh.10hCLN2 slowed the progression of disease in children with CLN2 disease. However, improvements in vector design and delivery strategies will be necessary to halt disease progression using gene therapy., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)
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- 2020
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14. The MEK inhibitor selumetinib reduces spinal neurofibroma burden in patients with NF1 and plexiform neurofibromas.
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Jackson S, Baker EH, Gross AM, Whitcomb P, Baldwin A, Derdak J, Tibery C, Desanto J, Carbonell A, Yohay K, O'Sullivan G, Chen AP, Widemann BC, and Dombi E
- Abstract
Background: Spinal neurofibromas (SNFs) in neurofibromatosis type 1 (NF1) can cause progressive spinal cord compression and neurological dysfunction. The MEK inhibitor selumetinib shrinks the majority of plexiform neurofibromas (PNs) in patients with NF1. We assessed the effect of selumetinib on SNF., Methods: Pediatric and adult patients with NF1 and inoperable PN participating in phase 2 studies of selumetinib for PN were included in this analysis if they had SNF and serial spine magnetic resonance imaging (MRI). Selumetinib was administered orally at the recommended dose of 25 mg/m
2 /dose twice daily (max 50 mg b.i.d.; 1 cycle = 28 days). We qualitatively assessed the effect of selumetinib on SNF-related spinal canal distortion, cerebrospinal fluid distribution, and spinal cord deformity on MRI., Results: Twenty-four patients (18 male), median age 16.9 years (range, 6.2-60.3), had SNF, 22 of which were associated with the same nerves as the target PN assessed on the clinical trial. Twenty patients had spinal cord deformity. Twenty-three patients completed at least 12 treatment cycles to date. Eighteen patients showed subtle to a marked improvement in SNF burden, 5 remained stable, and no worsening was observed during treatment., Conclusions: This is the first study describing the effect of selumetinib on SNF. Of 24 patients, 18 exhibited some improvement of SNF burden on imaging. These findings suggest that selumetinib may prevent the worsening of cord compression, potentially reducing the need for surgical interventions in select patients or benefitting patients who do not have a surgical option. Prospective evaluation of the clinical benefit of selumetinib for SNF is warranted., (Published by Oxford University Press on behalf of the Society for Neuro-Oncology and the European Association of Neuro-Oncology 2020.)- Published
- 2020
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15. The Use of MEK Inhibitors in Neurofibromatosis Type 1-Associated Tumors and Management of Toxicities.
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Klesse LJ, Jordan JT, Radtke HB, Rosser T, Schorry E, Ullrich N, Viskochil D, Knight P, Plotkin SR, and Yohay K
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- Child, Humans, Mitogen-Activated Protein Kinase Kinases, Protein Kinase Inhibitors adverse effects, Antineoplastic Agents therapeutic use, Neurofibroma, Plexiform drug therapy, Neurofibromatosis 1 drug therapy
- Abstract
Early-phase clinical trials using oral inhibitors of MEK, the mitogen-activated protein kinase kinase, have demonstrated benefit for patients with neurofibromatosis type 1 (NF1)-associated tumors, particularly progressive low-grade gliomas and plexiform neurofibromas. Given this potential of MEK inhibition as an effective medical therapy, the use of targeted agents in the NF1 population is likely to increase substantially. For clinicians with limited experience prescribing MEK inhibitors, concern about managing these treatments may be a barrier to use. In this manuscript, the Clinical Care Advisory Board of the Children's Tumor Foundation reviews the published experience with MEK inhibitors in NF1 and outlines recommendations for side-effect management, as well as monitoring guidelines. These recommendations can serve as a beginning framework for NF providers seeking to provide the most effective treatments for their patients. IMPLICATIONS FOR PRACTICE: Neurofibromatosis type 1 (NF1) clinical care is on the cusp of a transformative shift. With the success of recent clinical trials using MEK inhibitors, an increasing number of NF1 patients are being treated with MEK inhibitors for both plexiform neurofibromas and low-grade gliomas. The use of MEK inhibitors is likely to increase substantially in NF1. Given these changes, the Clinical Care Advisory Board of the Children's Tumor Foundation has identified a need within the NF1 clinical community for guidance for the safe and effective use of MEK inhibitors for NF1-related tumors. This article provides a review of the published experience of MEK inhibitors in NF1 and provides recommendations for monitoring and management of side effects., (© 2020 The Authors. The Oncologist published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.)
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- 2020
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16. Response to Hannah-Shmouni and Stratakis.
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Stewart DR, Korf BR, Nathanson KL, Stevenson DA, and Yohay K
- Subjects
- Adult, Genomics, Humans, United States, Genetics, Medical, Neurofibromatosis 1
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- 2019
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17. Comparison of hybrid 18F-fluorodeoxyglucose positron emission tomography/magnetic resonance imaging and positron emission tomography/computed tomography for evaluation of peripheral nerve sheath tumors in patients with neurofibromatosis type 1.
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Raad RA, Lala S, Allen JC, Babb J, Mitchell CW, Franceschi AM, Yohay K, and Friedman KP
- Abstract
Rapidly enlarging, painful plexiform neurofibromas (PN) in neurofibromatosis type 1 (NF1) patients are at higher risk for harboring a malignant peripheral nerve sheath tumor (MPNST). Fludeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) has been used to support more invasive diagnostic and therapeutic interventions. However, PET/CT imparts an untoward radiation hazard to this population with tumor suppressor gene impairment. The use of FDG PET coupled with magnetic resonance imaging (MRI) rather than CT is a safer alternative but its relative diagnostic sensitivity requires verification. Ten patients (6 females, 4 males, mean age 27 years, range 8-54) with NF1 and progressive PN were accrued from our institutional NF Clinic. Indications for PET scanning included increasing pain and/or progressive disability associated with an enlarging PN on serial MRIs. Following a clinically indicated whole-body FDG PET/CT, a contemporaneous PET/MRI was obtained using residual FDG activity with an average time interval of 3-4 h FDG-avid lesions were assessed for both maximum standardized uptake value (SUVmax) from PET/CT and SUVmax from PET/MR and correlation was made between the two parameters. 26 FDG avid lesions were detected on both PET/CT and PET/MR with an accuracy of 100%. SUVmax values ranged from 1.4-10.8 for PET/CT and from 0.2-5.9 for PET/MRI. SUVmax values from both modalities demonstrated positive correlation ( r = 0.45, P < 0.001). PET/MRI radiation dose was significantly lower (53.35% ± 14.37% [P = 0.006]). In conclusion, PET/MRI is a feasible alternative to PET/CT in patients with NF1 when screening for the potential occurrence of MPNST. Reduction in radiation exposure approaches 50% compared to PET/CT., Competing Interests: There are no conflicts of interest.
- Published
- 2018
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18. Accuracy of Reported Community Diagnosis of Autism Spectrum Disorder.
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Hausman-Kedem M, Kosofsky BE, Ross G, Yohay K, Forrest E, Dennin MH, Patel R, Bennett K, Holahan JP, and Ward MJ
- Abstract
To compare community diagnoses of Autism Spectrum Disorder (ASD) reported by parents to consensus diagnoses made using standardized tools plus clinical observation. 87 participants (85% male, average age 7.4 years), with reported community diagnosis of ASD were evaluated using the Autism Diagnostic Observation Schedule) (ADOS-2), Differential Ability Scale (DAS-II), and Vineland Adaptive Behavior Scales (VABS-II). Detailed developmental and medical history was obtained from all participants. Diagnosis was based on clinical consensus of at least two expert clinicians, using test results, clinical observations, and parent report. 23% of participants with a reported community diagnosis of ASD were classified as non-spectrum based on our consensus diagnosis. ASD and non-spectrum participants did not differ on age at evaluation and age of first community diagnosis. Non-verbal IQ scores and Adaptive Behavior Composite scores were significantly higher in the non-spectrum group compared to the ASD group (104.5 ± 21.7 vs. 80.1 ± 21.6, p < .01; 71.1 ± 15 versus 79.5 ± 17.6, p < .05, respectively). Participants enrolled with community diagnosis of PDD-NOS were significantly more likely to be classified as non-spectrum on the study consensus diagnosis than Participants with Autism or Asperger (36% versus 9.5%, Odds Ratio = 5.4, p < .05). This study shows suboptimal agreement between community diagnoses of ASD and consensus diagnosis using standardized instruments. These findings are based on limited data, and should be further studied, taking into consideration the influence of DSM 5 diagnostic criteria on ASD prevalence., Competing Interests: Conflict of Interest: Moran Hausman-Kedeml, Barry E. Kosofsky, Gail Ross, Kaleb Yohay, Emily Forrest, Margaret H. Dennin, Reena Patel, Kristen Bennett, James P. Holahan and Mary J. Ward declare that there is no conflict of interest.
- Published
- 2018
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19. Disease characteristics and progression in patients with late-infantile neuronal ceroid lipofuscinosis type 2 (CLN2) disease: an observational cohort study.
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Nickel M, Simonati A, Jacoby D, Lezius S, Kilian D, Van de Graaf B, Pagovich OE, Kosofsky B, Yohay K, Downs M, Slasor P, Ajayi T, Crystal RG, Kohlschütter A, Sondhi D, and Schulz A
- Subjects
- Adolescent, Child, Child, Preschool, Cohort Studies, Disease Progression, Female, Humans, Infant, Longitudinal Studies, Male, Tripeptidyl-Peptidase 1, Neuronal Ceroid-Lipofuscinoses diagnosis
- Abstract
Background: Late-infantile neuronal ceroid lipofuscinosis type 2 (CLN2) disease, characterised by rapid psychomotor decline and epilepsy, is caused by deficiency of the lysosomal enzyme tripeptidyl peptidase 1. We aimed to analyse the characteristics and rate of progression of CLN2 disease in an international cohort of patients., Methods: We did an observational cohort study using data from two independent, international datasets of patients with untreated genotypically confirmed CLN2 disease: the DEM-CHILD dataset (n=74) and the Weill Cornell Medical College (WCMC) dataset (n=66). Both datasets included quantitative rating assessments with disease-specific clinical domain scores, and disease course was measured longitudinally in 67 patients in the DEM-CHILD cohort. We analysed these data to determine age of disease onset and diagnosis, as well as disease progression-measured by the rate of decline in motor and language summary scores (on a scale of 0-6 points)-and time from first symptom to death., Findings: In the combined DEM-CHILD and WCMC dataset, median age was 35·0 months (IQR 24·0-38·5) at first clinical symptom, 37·0 months (IQR 35·0 -42·0) at first seizure, and 54·0 months (IQR 47·5-60·0) at diagnosis. Of 74 patients in the DEM-CHILD dataset, the most common first symptoms of disease were seizures (52 [70%]), language difficulty (42 [57%]), motor difficulty (30 [41%]), behavioural abnormality (12 [16%]), and dementia (seven [9%]). Among the 41 patients in the DEM-CHILD dataset for whom longitudinal assessments spanning the entire disease course were available, a rapid annual decline of 1·81 score units (95% CI 1·50-2·12) was seen in motor-language summary scores from normal (score of 6) to no function (score of 0), which occurred over approximately 30 months. Among 53 patients in the DEM-CHILD cohort with available data, the median time between onset of first disease symptom and death was 7·8 years (SE 0·9) years., Interpretation: In view of its natural history, late-infantile CLN2 disease should be considered in young children with delayed language acquisition and new onset of seizures. CLN2 disease has a largely predictable time course with regard to the loss of language and motor function, and these data might serve as historical controls for the assessment of current and future therapies., Funding: EU Seventh Framework Program, German Ministry of Education and Research, EU Horizon2020 Program, National Institutes of Health, Nathan's Battle Foundation, Cures Within Reach Foundation, Noah's Hope Foundation, Hope4Bridget Foundation., (Copyright © 2018 Elsevier Ltd. All rights reserved.)
- Published
- 2018
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20. Care of adults with neurofibromatosis type 1: a clinical practice resource of the American College of Medical Genetics and Genomics (ACMG).
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Stewart DR, Korf BR, Nathanson KL, Stevenson DA, and Yohay K
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- Genetic Testing standards, Genetics, Medical methods, Genomics standards, Humans, Neurofibromatosis 1 genetics, Neurofibromatosis 1 physiopathology, Neurofibromin 1 genetics, Neurofibromin 1 metabolism, United States, Neurofibromatosis 1 complications, Neurofibromatosis 1 therapy
- Abstract
Disclaimer: This practice resource is designed primarily as an educational resource for medical geneticists and other clinicians to help them provide quality medical services. Adherence to this practice resource is completely voluntary and does not necessarily assure a successful medical outcome. This practice resource should not be considered inclusive of all proper procedures and tests or exclusive of other procedures and tests that are reasonably directed to obtaining the same results. In determining the propriety of any specific procedure or test, the clinician should apply his or her own professional judgment to the specific clinical circumstances presented by the individual patient or specimen. Clinicians are encouraged to document the reasons for the use of a particular procedure or test, whether or not it is in conformance with this practice resource. Clinicians also are advised to take notice of the date this practice resource was adopted, and to consider other medical and scientific information that becomes available after that date. It also would be prudent to consider whether intellectual property interests may restrict the performance of certain tests and other procedures., Purpose: Neurofibromatosis type 1 (NF1) is an autosomal dominant disorder that is caused by a heterozygous loss-of-function variant in the tumor suppressor gene NF1; it affects ~1/1,900-1/3,500 people worldwide. The disorder is associated with an 8-15-year reduction in average life expectancy in both men and women, primarily due to malignant neoplasms and cardiovascular causes., Methods: A work group of experts sought to determine the prevalence, morbidity and mortality, and available treatments of common and emerging NF1-related clinical problems in adults. Work-group members identified peer-reviewed publications from PubMed. Publications derived from populations and multi-institution cohorts were prioritized. Recommendations for management arose by consensus from this literature and the collective expertise of the authors., Results: Malignant peripheral nerve sheath tumor (MPNST), breast cancer, cutaneous neurofibromas, and significant psychiatric and neurologic diagnoses are common problems in patients with NF1., Conclusion: Patient education and sensitization to worrisome signs and symptoms such as progressive severe pain (MPNST), changes in tumor volume (MPNST), new, unexplained neurologic symptoms (MPNST, brain tumors), and diaphoresis/palpitations (pheochromocytoma) are important. Although many issues in adults with NF1 can be managed by an internist or family physician, we strongly encourage evaluation by, and care coordination with, a specialized NF1 clinic.
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- 2018
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21. Brain Region-Specific Degeneration with Disease Progression in Late Infantile Neuronal Ceroid Lipofuscinosis (CLN2 Disease).
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Dyke JP, Sondhi D, Voss HU, Yohay K, Hollmann C, Mancenido D, Kaminsky SM, Heier LA, Rudser KD, Kosofsky B, Casey BJ, Crystal RG, and Ballon D
- Subjects
- Child, Disease Progression, Female, Humans, Magnetic Resonance Imaging, Male, Retrospective Studies, Tripeptidyl-Peptidase 1, Brain pathology, Nerve Degeneration pathology, Neuronal Ceroid-Lipofuscinoses pathology
- Abstract
Background and Purpose: Late infantile neuronal ceroid lipofuscinosis (CLN2 disease) is a uniformly fatal lysosomal storage disease resulting from mutations in the CLN2 gene. Our hypothesis was that regional analysis of cortical brain degeneration may identify brain regions that are affected earliest and most severely by the disease., Materials and Methods: Fifty-two high-resolution 3T MR imaging datasets were prospectively acquired on 38 subjects with CLN2. A retrospective cohort of 52 disease-free children served as a control population. The FreeSurfer software suite was used for calculation of cortical thickness., Results: An increased rate of global cortical thinning in CLN2 versus control subjects was the primary finding in this study. Three distinct patterns were observed across brain regions. In the first, subjects with CLN2 exhibited differing rates of cortical thinning versus age. This was true in 22 and 26 of 34 regions in the left and right hemispheres, respectively, and was also clearly discernable when considering brain lobes as a whole and Brodmann regions. The second pattern exhibited a difference in thickness from healthy controls but with no discernable change with age (9 left hemispheres, 5 right hemispheres). In the third pattern, there was no difference in either the rate of cortical thinning or the mean cortical thickness between groups (3 left hemispheres, 3 right hemispheres)., Conclusions: This study demonstrates that CLN2 causes differential rates of degeneration across the brain. Anatomic and functional regions that degenerate sooner and more severely than others compared with those in healthy controls may offer targets for directed therapies. The information gained may also provide neurobiologic insights regarding the mechanisms underlying disease progression., (© 2016 by American Journal of Neuroradiology.)
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- 2016
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22. Neuro-behçet disease in an african american adolescent.
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Merkler AE, Maciel CB, May AS, Vargas WS, and Yohay K
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- 2015
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23. Efficacy of local polymer-based and systemic delivery of the anti-glutamatergic agents riluzole and memantine in rat glioma models.
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Yohay K, Tyler B, Weaver KD, Pardo AC, Gincel D, Blakeley J, Brem H, and Rothstein JD
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- Animals, Cell Line, Tumor, Disease Models, Animal, Excitatory Amino Acid Antagonists administration & dosage, Memantine administration & dosage, Mice, Polymers administration & dosage, Polymers therapeutic use, Rats, Riluzole administration & dosage, Brain Neoplasms drug therapy, Drug Delivery Systems methods, Excitatory Amino Acid Antagonists therapeutic use, Glioma drug therapy, Memantine therapeutic use, Riluzole therapeutic use
- Abstract
Object: The poor outcome of malignant gliomas is largely due to local invasiveness. Previous studies suggest that gliomas secrete excess glutamate and destroy surrounding normal peritumoral brain by means of excitotoxic mechanisms. In this study the authors assessed the effect on survival of 2 glutamate modulators (riluzole and memantine) in rodent glioma models., Methods: In an in vitro growth inhibition assay, F98 and 9L cells were exposed to riluzole and memantine. Mouse cerebellar organotypic cultures were implanted with F98 glioma cells and treated with radiation, radiation + riluzole, or vehicle and assessed for tumor growth. Safety and tolerability of intracranially implanted riluzole and memantine CPP:SA polymers were tested in F344 rats. The efficacy of these drugs was tested against the 9L model and riluzole was further tested with and without radiation therapy (RT)., Results: In vitro assays showed effective growth inhibition of both drugs on F98 and 9L cell lines. F98 organotypic cultures showed reduced growth of tumors treated with radiation and riluzole in comparison with untreated cultures or cultures treated with radiation or riluzole alone. Three separate efficacy experiments all showed that localized delivery of riluzole or memantine is efficacious against the 9L gliosarcoma tumor in vivo. Systemic riluzole monotherapy was ineffective; however, riluzole given with RT resulted in improved survival., Conclusions: Riluzole and memantine can be safely and effectively delivered intracranially via polymer in rat glioma models. Both drugs demonstrate efficacy against the 9L gliosarcoma and F98 glioma in vitro and in vivo. Although systemic riluzole proved ineffective in increasing survival, riluzole acted synergistically with radiation and increased survival compared with RT or riluzole alone.
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- 2014
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24. Incidental parenchymal magnetic resonance imaging findings in the brains of patients with neurofibromatosis type 2.
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Vargas WS, Heier LA, Rodriguez F, Bergner A, and Yohay K
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- Adolescent, Adult, Aged, Child, Female, Humans, Incidental Findings, Male, Middle Aged, Reproducibility of Results, Sensitivity and Specificity, Young Adult, Brain pathology, Brain Neoplasms pathology, Diffusion Magnetic Resonance Imaging methods, Neurofibromatosis 2 pathology
- Abstract
Purpose: Whereas T2 hyperintensities known as NF-associated bright spots are well described in patients with neurofibromatosis type I (NF-1), there is a paucity of data on incidental findings in patients with neurofibromatosis type II (NF-2). We aim to characterize unexplained imaging findings in the brains of patients with NF-2., Materials and Methods: This study is retrospective, HIPAA-compliant and approved by the institutional review board. 34 patients with NF-2 underwent brain magnetic resonance imaging (MRI) between January 2000 and December 2012. T2 and T1-weighted imaging characteristics, diffusion weighted imaging (DWI) characteristics, and enhancement patterns were analyzed by visual inspection. Clinical information at time of imaging was available for all patients. Neuropathologic data was available for one patient., Results: We found unexplained T2 hyperintensities present on initial imaging in 23/34 patients (67%). Of the 23 patients with unexplained MRI findings, 15 (65%) had wedge-shaped T2 hyperintensities in the subcortical white matter extending to the cortex suggestive of a cortical dysplasia. 3 additional cases (17%) had a lesion within the cerebellum suggestive of a neuronal migration anomaly. In one patient where the MRI was suggestive of focal cortical dysplasia, histopathologic analysis revealed dysplastic glial foci without other alterations of cortical architecture or other cytologic abnormalities., Conclusion: Unexplained T2 hyperintensities occur frequently in patients with NF-2. While they may not be the NF-2 equivalent of NF-associated bright spots seen in NF-1, some of these T2 hyperintensities in patients with NF-2 may represent underlying disorders of neuronal migration. Further studies are needed to validate our findings.
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- 2014
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25. Spectrum of ocular manifestations in CLN2-associated batten (Jansky-Bielschowsky) disease correlate with advancing age and deteriorating neurological function.
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Orlin A, Sondhi D, Witmer MT, Wessel MM, Mezey JG, Kaminsky SM, Hackett NR, Yohay K, Kosofsky B, Souweidane MM, Kaplitt MG, D'Amico DJ, Crystal RG, and Kiss S
- Subjects
- Adolescent, Adult, Age Factors, Aged, Aged, 80 and over, Aminopeptidases genetics, Dipeptidyl-Peptidases and Tripeptidyl-Peptidases genetics, Eye Diseases genetics, Female, Humans, Male, Middle Aged, Mutation, Neuronal Ceroid-Lipofuscinoses genetics, Serine Proteases genetics, Severity of Illness Index, Tripeptidyl-Peptidase 1, Eye Diseases etiology, Eye Diseases pathology, Eye Diseases physiopathology, Neuronal Ceroid-Lipofuscinoses complications, Neuronal Ceroid-Lipofuscinoses pathology, Neuronal Ceroid-Lipofuscinoses physiopathology
- Abstract
Background: Late infantile neuronal ceroid lipofuscinosis (LINCL), one form of Batten's disease is a progressive neurodegenerative disorder resulting from a CLN2 gene mutation. The spectrum of ophthalmic manifestations of LINCL and the relationship with neurological function has not been previously described., Methods: Patients underwent ophthalmic evaluations, including anterior segment and dilated exams, optical coherence tomography, fluorescein and indocyanine green angiography. Patients were also assessed with the LINCL Neurological Severity Scale. Ophthalmic findings were categorized into one of five severity scores, and the association of the extent of ocular disease with neurological function was assessed., Results: Fifty eyes of 25 patients were included. The mean age at the time of exam was 4.9 years (range 2.5 to 8.1). The mean ophthalmic severity score was 2.6 (range 1 to 5). The mean neurological severity score was 6.1 (range 2 to 11). Significantly more severe ophthalmic manifestations were observed among older patients (p<0.005) and patients with more severe neurological findings (p<0.03). A direct correlation was found between the Ophthalmic Severity Scale and the Weill Cornell Neurological Scale (p<0.002). A direct association was also found between age and the ophthalmic manifestations (p<0.0002), with older children having more severe ophthalmic manifestations., Conclusions: Ophthalmic manifestations of LINCL correlate closely with the degree of neurological function and the age of the patient. The newly established LINCL Ophthalmic Scale may serve as an objective marker of LINCL severity and disease progression, and may be valuable in the evaluation of novel therapeutic strategies for LINCL, including gene therapy.
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- 2013
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26. Assessment of disease severity in late infantile neuronal ceroid lipofuscinosis using multiparametric MR imaging.
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Dyke JP, Sondhi D, Voss HU, Shungu DC, Mao X, Yohay K, Worgall S, Hackett NR, Hollmann C, Yeotsas ME, Jeong AL, Van de Graaf B, Cao I, Kaminsky SM, Heier LA, Rudser KD, Souweidane MM, Kaplitt MG, Kosofsky B, Crystal RG, and Ballon D
- Subjects
- Age Factors, Aminopeptidases genetics, Artifacts, Biomarkers metabolism, Brain metabolism, Child, Child, Preschool, Databases, Factual, Dipeptidyl-Peptidases and Tripeptidyl-Peptidases genetics, Disease Progression, Female, Humans, Male, Neuronal Ceroid-Lipofuscinoses genetics, Serine Proteases genetics, Tripeptidyl-Peptidase 1, Brain pathology, Magnetic Resonance Imaging methods, Neuronal Ceroid-Lipofuscinoses pathology, Severity of Illness Index
- Abstract
Background and Purpose: LINCL is a uniformly fatal lysosomal storage disease resulting from mutations in the CLN2 gene that encodes for tripeptidyl peptidase 1, a lysosomal enzyme necessary for the degradation of products of cellular metabolism. With the goal of developing quantitative noninvasive imaging biomarkers sensitive to disease progression, we evaluated a 5-component MR imaging metric and tested its correlation with a clinically derived disease-severity score., Materials and Methods: MR imaging parameters were measured across the brain, including quantitative measures of the ADC, FA, nuclear spin-spin relaxation times (T2), volume percentage of CSF (%CSF), and NAA/Cr ratios. Thirty MR imaging datasets were prospectively acquired from 23 subjects with LINCL (2.5-8.4 years of age; 8 male/15 female). Whole-brain histograms were created, and the mode and mean values of the histograms were used to characterize disease severity., Results: Correlation of single MR imaging parameters against the clinical disease-severity scale yielded linear regressions with R2 ranging from 0.25 to 0.70. Combinations of the 5 biomarkers were evaluated by using PCA. The best combination included ADC, %CSF, and NAA/Cr (R2=0.76, P<.001)., Conclusions: The multiparametric disease-severity score obtained from the combination of ADC, %CSF, and NAA/Cr whole-brain MR imaging techniques provided a robust measure of disease severity, which may be useful in clinical therapeutic trials of LINCL in which an objective assessment of therapeutic response is desired.
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- 2013
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27. Ophthalmic artery ischemic syndrome associated with neurofibromatosis and moyamoya syndrome.
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Witmer MT, Levy R, Yohay K, and Kiss S
- Subjects
- Arterial Occlusive Diseases diagnosis, Carotid Artery Diseases diagnosis, Carotid Artery Diseases etiology, Carotid Artery Diseases surgery, Carotid Artery, Internal pathology, Cerebral Angiography, Cerebral Revascularization, Choroid blood supply, Choroid pathology, Female, Fluorescein Angiography, Humans, Infant, Infarction, Ischemia diagnosis, Magnetic Resonance Angiography, Moyamoya Disease diagnosis, Necrosis, Neurofibromatosis 1 diagnosis, Retinal Vessels physiopathology, Arterial Occlusive Diseases etiology, Ischemia etiology, Moyamoya Disease complications, Neurofibromatosis 1 complications, Ophthalmic Artery
- Published
- 2013
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28. Long-term expression and safety of administration of AAVrh.10hCLN2 to the brain of rats and nonhuman primates for the treatment of late infantile neuronal ceroid lipofuscinosis.
- Author
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Sondhi D, Johnson L, Purpura K, Monette S, Souweidane MM, Kaplitt MG, Kosofsky B, Yohay K, Ballon D, Dyke J, Kaminksy SM, Hackett NR, and Crystal RG
- Subjects
- Aminopeptidases metabolism, Animals, Antibodies, Neutralizing immunology, Antibodies, Viral immunology, Behavior, Animal, Brain pathology, Cell Line, Dependovirus immunology, Dipeptidyl-Peptidases and Tripeptidyl-Peptidases metabolism, Female, Genetic Therapy, Genetic Vectors administration & dosage, Genetic Vectors adverse effects, Humans, Male, Neuronal Ceroid-Lipofuscinoses metabolism, Neuronal Ceroid-Lipofuscinoses therapy, Primates, Rats, Serine Proteases metabolism, Time Factors, Transduction, Genetic, Tripeptidyl-Peptidase 1, Aminopeptidases genetics, Brain metabolism, Dependovirus genetics, Dipeptidyl-Peptidases and Tripeptidyl-Peptidases genetics, Gene Expression, Genetic Vectors genetics, Neuronal Ceroid-Lipofuscinoses genetics, Serine Proteases genetics
- Abstract
Late infantile neuronal ceroid lipofuscinosis (LINCL), a fatal, lysosomal storage disorder caused by mutations in the CLN2 gene, results in a deficiency of tripeptidyl-peptidase I (TPP-I) activity in neurons. Our prior studies showed that delivery of the human CLN2 cDNA directly to the CNS, using an adeno-associated virus serotype 2 (AAV2) vector, is safe in children with LINCL. As a second-generation strategy, we have demonstrated that AAVrh.10hCLN2, a rhesus-derived AAV vector, mediates wide distribution of TPP-I through the CNS in a murine model. This study tests the hypothesis that direct administration of AAVrh.10hCLN2 to the CNS of rats and nonhuman primates at doses scalable to humans has an acceptable safety profile and mediates significant CLN2 expression in the CNS. A dose of 10(11) genome copies (GC) was administered bilaterally to the striatum of Sprague Dawley rats with sacrifice at 7 and 90 days with no significant impact except for mild vector-related histopathological changes at the site of vector administration. A dose of 1.8×10(12) GC of AAVrh.10hCLN2 was administered to the CNS of 8 African green monkeys. The vector-treated monkeys did not differ from controls in any safety parameter except for mild to moderate white matter edema and inflammation localized to the administration sites of the vector. There were no clinical sequelae to these localized findings. TPP-I activity was >2 SD over background in 31.7±8.1% of brain at 90 days. These findings establish the dose and safety profile for human clinical studies for the treatment of LINCL with AAVrh.10hCLN2.
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- 2012
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29. Orthopaedic aspects of neurofibromatosis: update.
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Delucia TA, Yohay K, and Widmann RF
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- Bone Diseases, Developmental drug therapy, Bone Neoplasms drug therapy, Child, Humans, Neurofibromatosis 1 drug therapy, Bone Diseases, Developmental complications, Bone Neoplasms complications, Neurofibromatosis 1 complications
- Abstract
Purpose of Review: Neurofibromatosis type I (NF-1), affecting 1: 3000 people, is one of the most common disorders of the nervous system, and most pediatricians will care for a patient with this condition. It is imperative that careful attention be paid to screening for scoliosis and tibial dysplasia. Prompt referral to an orthopaedist at the time of diagnosis, as well as neurologist, ophthalmologist, and dermatologist, will provide a global spectrum of care for the individual. Patient care between surgical procedures will be inevitable, with 70% of patients with NF-1 undergoing hospitalization or surgery., Recent Findings: This review provides a description of diagnosis, presurgical evaluation, and advances in understanding tibial dysplasia, scoliosis and malignant peripheral nerve sheath tumors. New pharmaceutical treatments such as lovastatin have improved bone healing in vivo and induced apoptosis in vitro. Multiple pharmaceuticals have shown neurofibroma arrest in vitro and are in phase II clinical trials., Summary: As animal models improve and clinical trials proceed, there is momentum toward eliminating the musculoskeletal morbidity associated with NF-1.
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- 2011
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30. Consensus recommendations to accelerate clinical trials for neurofibromatosis type 2.
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Evans DG, Kalamarides M, Hunter-Schaedle K, Blakeley J, Allen J, Babovic-Vuskanovic D, Belzberg A, Bollag G, Chen R, DiTomaso E, Golfinos J, Harris G, Jacob A, Kalpana G, Karajannis M, Korf B, Kurzrock R, Law M, McClatchey A, Packer R, Roehm P, Rubenstein A, Slattery W 3rd, Tonsgard JH, Welling DB, Widemann B, Yohay K, and Giovannini M
- Subjects
- Animals, Auditory Brain Stem Implants, Cochlear Implants, Drug Evaluation, Preclinical methods, Drug Evaluation, Preclinical trends, Humans, Meningeal Neoplasms therapy, Meningioma therapy, Neurofibromatosis 2 diagnosis, Time Factors, Clinical Trials as Topic methods, Consensus, Health Planning Guidelines, Neurofibromatosis 2 therapy
- Abstract
Purpose: Neurofibromatosis type 2 (NF2) is a rare autosomal dominant disorder associated primarily with bilateral schwannomas seen on the superior vestibular branches of the eighth cranial nerves. Significant morbidity can result from surgical treatment of these tumors. Meningiomas, ependymomas, and other benign central nervous system tumors are also common in NF2. The lack of effective treatments for NF2 marks an unmet medical need., Experimental Design: Here, we provide recommendations from a workshop, cochaired by Drs. D. Gareth Evans and Marco Giovannini, of 36 international researchers, physicians, representatives of the biotechnology industry, and patient advocates on how to accelerate progress toward NF2 clinical trials., Results: Workshop participants reached a consensus that, based on current knowledge, the time is right to plan and implement NF2 clinical trials. Obstacles impeding NF2 clinical trials and how to address them were discussed, as well as the candidate therapeutic pipeline for NF2., Conclusions: Both phase 0 and phase II NF2 trials are near-term options for NF2 clinical trials. The number of NF2 patients in the population remains limited, and successful recruitment will require ongoing collaboration efforts between NF2 clinics.
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- 2009
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31. Neurofibromatosis type 1 and associated malignancies.
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Yohay K
- Subjects
- Animals, Humans, Nervous System Neoplasms classification, Neurofibromatosis 1 diagnosis, Neurofibromatosis 1 genetics, Proto-Oncogene Mas, Breast Neoplasms complications, Leukemia complications, Nervous System Neoplasms complications, Neurofibromatosis 1 complications, Pheochromocytoma complications
- Abstract
Neurofibromatosis type 1 (NF1) is a common autosomal dominant neurocutaneous disorder with a predisposition to the development of benign and malignant tumors. Mutations in the NF1 gene result in loss of function of neurofibromin, a guanosine triphosphatase-activating protein that helps maintain the proto-oncogene Ras in its inactive form. Loss of neurofibromin results in increased proliferation and tumorigenesis. As a result, people with NF1 are at increased risk for the development of nervous and non-nervous system malignancies. Malignancy is a major source of morbidity and mortality in NF1. The natural history of NF1-associated malignancies is often different than that of their sporadic counterparts and, as such, management strategies need to be adjusted accordingly.
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- 2009
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32. A neurologic presentation of familial hemophagocytic lymphohistiocytosis which mimicked septic emboli to the brain.
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Turtzo LC, Lin DD, Hartung H, Barker PB, Arceci R, and Yohay K
- Subjects
- Bone Marrow Transplantation, Diagnosis, Differential, Follow-Up Studies, Heterozygote, Humans, Immunotherapy, Infant, Intracranial Embolism microbiology, Lymphohistiocytosis, Hemophagocytic genetics, Lymphohistiocytosis, Hemophagocytic metabolism, Lymphohistiocytosis, Hemophagocytic therapy, Magnetic Resonance Imaging, Male, Membrane Glycoproteins genetics, Perforin, Polymorphism, Single Nucleotide, Pore Forming Cytotoxic Proteins genetics, Sepsis pathology, Treatment Outcome, Intracranial Embolism pathology, Lymphohistiocytosis, Hemophagocytic pathology, Membrane Glycoproteins metabolism, Pore Forming Cytotoxic Proteins metabolism
- Abstract
Familial hemophagocytic lymphohistiocytosis is an inherited deficiency of natural killer cell function and excessive cytokine activity, which predominantly presents in early childhood. The initial symptoms of familial hemophagocytic lymphohistiocytosis are often nonspecific but may be predominantly neurologic. The case presented here describes an 18-month-old boy who initially presented with fever, encephalopathy, and hemiparesis. He had innumerable brain lesions visualized on magnetic resonance imaging scans. An infectious etiology was excluded, and brain, liver, and bone marrow biopsies were nonspecific but consistent with hemophagocytic lymphohistiocytosis. Cells were sent for flow cytometry perforin analysis, which demonstrated defective natural killer cell function. A diagnosis of familial hemophagocytic lymphohistiocytosis was confirmed by mutation analysis and decreased expression of the perforin gene, in the patient and immediate family members. These results showed the patient to be a compound heterozygote for perforin mutations. His case illustrates the potential for a fulminant neurological presentation of familial hemophagocytic lymphohistiocytosis with widespread lesions in the brain.
- Published
- 2007
- Full Text
- View/download PDF
33. Inverse correlation between cerebral blood flow measured by continuous arterial spin-labeling (CASL) MRI and neurocognitive function in children with sickle cell anemia (SCA).
- Author
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Strouse JJ, Cox CS, Melhem ER, Lu H, Kraut MA, Razumovsky A, Yohay K, van Zijl PC, and Casella JF
- Subjects
- Blood Flow Velocity, Child, Data Interpretation, Statistical, Follow-Up Studies, Humans, Linear Models, Magnetic Resonance Imaging statistics & numerical data, Prospective Studies, Sensitivity and Specificity, Spin Labels, Anemia, Sickle Cell physiopathology, Cerebral Arteries, Cerebrovascular Circulation, Cognition Disorders physiopathology, Magnetic Resonance Imaging methods, Neuropsychological Tests
- Abstract
Overt stroke, clinically "silent" cerebral infarct, and neurocognitive impairment are frequent complications of sickle cell anemia (SCA). Current imaging techniques have limited sensitivity and specificity to identify children at risk for neurocognitive impairment. We prospectively evaluated 24 children with SCA with a neurologic exam, complete blood count, transcranial Doppler ultrasound (TCD), measurement of intelligence quotient (IQ), and magnetic resonance imaging (MRI) with measurement of cerebral blood flow (CBF) using continuous arterial spin-labeling (CASL) MRI. Average CBF to gray matter was 112 +/- 36 mL/100 g/min. We identified a strong inverse relationship between performance IQ and CBF (-1.5 points per 10 mL/100 g/min increase in CBF, P = .013). Elevated steady-state white blood cell count (> or = 14 x 10(9)/L [14,000/microL]) was associated with lower full scale IQ (86 +/- 9 vs 99 +/- 10, P = .005). CASL MRI may identify children with neurocognitive impairment, before damage is evident by structural MRI or TCD.
- Published
- 2006
- Full Text
- View/download PDF
34. Neurofibromatosis types 1 and 2.
- Author
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Yohay K
- Subjects
- Central Nervous System Neoplasms etiology, Central Nervous System Neoplasms genetics, Central Nervous System Neoplasms pathology, Humans, Nerve Sheath Neoplasms etiology, Nerve Sheath Neoplasms genetics, Nerve Sheath Neoplasms pathology, Neurofibromatosis 1 genetics, Neurofibromatosis 1 mortality, Neurofibromatosis 1 pathology, Neurofibromatosis 2 genetics, Neurofibromatosis 2 mortality, Neurofibromatosis 2 pathology, Neurofibromatosis 1 therapy, Neurofibromatosis 2 therapy
- Abstract
Background: Neurofibromatosis types 1 and 2 (NF1 and NF2) are autosomal dominant neurocutaneous disorders with some similarities and many differences. They are frequently discussed together and often confused for one another by clinicians. Both disorders have widely variable presentations and degrees of severity. A thorough understanding of these complex disorders is essential for proper medical management, anticipatory care, and patient education., Review Summary: In this article, the clinical features, genetics, pathogenesis, and management of neurofibromatosis types 1 and 2 are reviewed and compared., Conclusions: NF1 and NF2 are complex genetic disorders with numerous manifestations and wide phenotypic variability. The complex nature of these disorders requires coordinated multidisciplinary care.
- Published
- 2006
- Full Text
- View/download PDF
35. Panuveitis in association with pseudotumor cerebri.
- Author
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Margalit E, Sung JU, Do DV, Yohay K, and Nguyen QD
- Subjects
- Child, Female, Humans, Panuveitis diagnosis, Panuveitis therapy, Pseudotumor Cerebri diagnosis, Pseudotumor Cerebri therapy, Panuveitis etiology, Pseudotumor Cerebri complications
- Abstract
We report a case of an 11-year-old girl with bilateral panuveitis in association with pseudotumor cerebri. The patient underwent complete ophthalmologic, neurologic, and laboratory evaluations and was treated with therapy for pseudotumor cerebri. The patient met the diagnostic criteria for pseudotumor cerebri and also had panuveitis. Symptoms and findings of pseudotumor cerebri and panuveitis improved significantly after combination therapy of oral acetazolamide and weight reduction. The index case illustrates that pseudotumor cerebri can be associated with panuveitis. Therapy for pseudotumor cerebri might also help with the resolution of uveitis.
- Published
- 2005
- Full Text
- View/download PDF
36. Practice parameter: evaluation of the child with global developmental delay.
- Author
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Crawford TO, Comi A, Freeman JM, Kossoff EH, Singer H, Vining EP, and Yohay K
- Subjects
- Child, Diagnostic Techniques, Neurological economics, Diagnostic Tests, Routine economics, Humans, Pediatrics standards, Practice Guidelines as Topic standards, Predictive Value of Tests, Developmental Disabilities diagnosis, Diagnostic Techniques, Neurological standards, Neurology methods, Neurology standards
- Published
- 2003
37. Offense produced by chemical stimulation of the anterior hypothalamus of the rat.
- Author
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Adams DB, Boudreau W, Cowan CW, Kokonowski C, Oberteuffer K, and Yohay K
- Subjects
- Aggression drug effects, Aggression physiology, Agonistic Behavior physiology, Animals, Brain Mapping, Female, GABA Antagonists, Hypothalamus, Anterior physiology, Male, Motor Activity drug effects, Motor Activity physiology, Preoptic Area drug effects, Preoptic Area physiology, Rats, Rats, Inbred Strains, Receptors, GABA-A drug effects, Receptors, GABA-A physiology, Sexual Behavior, Animal drug effects, Sexual Behavior, Animal physiology, gamma-Aminobutyric Acid physiology, Agonistic Behavior drug effects, Hypothalamus, Anterior drug effects, Picrotoxin pharmacology
- Abstract
Offense behavior, including bite-and-kick attack, was obtained by microinjections of picrotoxin into the anterior hypothalamus of the rat. This is the first time that it has been possible to obtain offense by chemical stimulation of the brain, and the localization is more precise than that obtained with electrical stimulation. Mounting behavior and mounting by the opponent were also obtained from the anterior hypothalamus, the former corresponding to results obtained by previous studies using electrical stimulation. Other behaviors obtained from the hypothalamus included locomotion and circling, social and self-grooming, upright posture and boxing, digging, feeding, and leaping.
- Published
- 1993
- Full Text
- View/download PDF
38. Song-selective auditory input to a forebrain vocal control nucleus in the zebra finch.
- Author
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Vicario DS and Yohay KH
- Subjects
- Animals, Feedback, Ketamine, Male, Reaction Time physiology, Urethane, Xylazine, Auditory Pathways physiology, Birds physiology, Prosencephalon physiology, Vocalization, Animal physiology
- Abstract
Neurons in nuclei on the motor pathway for vocalizations in songbirds are known to respond to sound stimuli. The auditory responses in one such nucleus, robustus archistriatalis (RA), were characterized by making multi-unit recordings in awake and anesthetized adult male zebra finches and in birds that had received lesions of the input to RA from the lateral part of the magnocellular nucleus of the anterior neostriatum (LMAN) or the Higher Vocal Center (HVC). In awake birds, RA neurons have a high level of spontaneous activity and vigorous auditory responses to song stimuli. Significantly greater responses are seen to the bird's own song (BOS) than to BOS played in reverse (REV) or to the songs of conspecifics (CON). Under ketamine-xylazine anesthesia, spontaneous activity is reduced, response latency increases and responses to BOS, REV and CON are indistinguishable. Responses obtained under urethane anesthesia are similar to those seen in awake birds. Thus, the pattern and selectivity of auditory responses in RA depend on the animal's state. Auditory responses in RA are qualitatively unchanged following lesion of the input to RA from LMAN, indicating that this pathway is not required for the sensory processing that underlies the preference for BOS on the vocal production pathway. Our results show that an input other than that from LMAN must be primarily responsible for auditory responses in RA. The direct projection from HVC is the most likely pathway by which song selective auditory information arrives in RA, since lesioning HVC abolished auditory responses in RA.
- Published
- 1993
- Full Text
- View/download PDF
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