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Erridge S, Leung O, Holvey C, Coomber R, Beri S, Khan S, Weatherall MW, Rucker JJ, Platt MW, Sodergren MH. An observational study of clinical outcome measures in patients treated with cannabis-based medicinal products on the UK Medical Cannabis Registry. Neuropsychopharmacol Rep 2023; 43:616-632. [PMID: 38057993 PMCID: PMC10739137 DOI: 10.1002/npr2.12403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 11/08/2023] [Accepted: 11/13/2023] [Indexed: 12/08/2023] Open
Abstract
INTRODUCTION While there is increasing evidence of the effects of cannabis-based medicinal products (CBMPs) on health-related quality of life (HRQoL), a major limitation of the current literature is the heterogeneity of studied CBMPs. This study aims to analyze changes in HRQoL in patients prescribed a homogenous selection of CBMPs. METHODS Primary outcomes were changes in patient-reported outcomes (PROMs) at 1, 3, 6, and 12 months from baseline. The secondary outcome was an adverse events analysis. Statistical significance was defined as p < 0.050. RESULTS 1378 patients prescribed Adven® CBMPs (Curaleaf International, Guernsey, UK) were included in the final analysis. 581 (42.16%) participants were current users of cannabis at baseline. 641 (46.51%), 235 (17.05%), and 502 (36.43%) patients were treated with oils, dried flowers, or a combination of the two, respectively. Improvements were found in all PROMs in each route of administration at 1, 3, 6, and 12 months from baseline (p < 0.010). Those prescribed dried flower only or both oils and dried flower experienced greater improvements in GAD-7, SQS, and EQ-5D-5L index values at 12 months (p < 0.050). There was no difference in outcomes between those prescribed dried flower only or dried flower with oils (p > 0.050). 3663 (265.82%) adverse events were reported by 297 (21.55%) patients. CONCLUSION There was an associated improvement in self-reported anxiety, sleep quality, and HRQoL in patients treated with the CBMPs. Those prescribed treatment formulations including dried flower were most likely to show a clinical improvement. However, these results must be interpreted with caution given the limitations of study design.
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Affiliation(s)
- Simon Erridge
- Imperial College Medical Cannabis Research Group, Department of Surgery and CancerImperial College LondonLondonUK
- Sapphire Medical ClinicsLondonUK
| | - Ophilia Leung
- Imperial College Medical Cannabis Research Group, Department of Surgery and CancerImperial College LondonLondonUK
| | | | - Ross Coomber
- Sapphire Medical ClinicsLondonUK
- St. George's Hospital NHS TrustLondonUK
| | - Sushil Beri
- Imperial College Medical Cannabis Research Group, Department of Surgery and CancerImperial College LondonLondonUK
- Sapphire Medical ClinicsLondonUK
| | - Shaheen Khan
- Sapphire Medical ClinicsLondonUK
- Guy's & St. Thomas' NHS Foundation TrustLondonUK
| | - Mark W. Weatherall
- Sapphire Medical ClinicsLondonUK
- Buckinghamshire Healthcare NHS TrustAmershamUK
| | - James J. Rucker
- Sapphire Medical ClinicsLondonUK
- Department of Psychological MedicineKings College LondonLondonUK
- South London & Maudsley NHS Foundation TrustLondonUK
| | | | - Mikael H. Sodergren
- Imperial College Medical Cannabis Research Group, Department of Surgery and CancerImperial College LondonLondonUK
- Sapphire Medical ClinicsLondonUK
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2
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Olsson F, Erridge S, Tait J, Holvey C, Coomber R, Beri S, Hoare J, Khan S, Weatherall MW, Platt M, Rucker JJ, Sodergren MH. An observational study of safety and clinical outcome measures across patient groups in the United Kingdom Medical Cannabis Registry. Expert Rev Clin Pharmacol 2023; 16:257-266. [PMID: 36848456 DOI: 10.1080/17512433.2023.2183841] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
BACKGROUND There is a paucity of high-quality data on patient outcomes and safety after initiating treatment with cannabis-based medicinal products (CBMPs). The aim of this study was to assess the clinical outcomes and safety of CBMPs by analyzing patient-reported outcome measures and adverse events across a broad spectrum of chronic conditions. RESEARCH DESIGN AND METHODS This study analyzed patients enrolled in the UK Medical Cannabis Registry. Participants completed the EQ-5D-5L to assess health-related quality of life, Generalized Anxiety Disorder-7 (GAD-7) questionnaire to measure anxiety severity, and the Single-item Sleep Quality Scale (SQS) to rate sleep quality at baseline and follow-up after 1, 3, 6, and 12 months. RESULTS A total of 2833 participants met inclusion criteria. The EQ-5D-5L index value, GAD-7, and SQS all improved at each follow-up (p < 0.001). There was no difference in EQ-5D-5L index values between former or current illicit cannabis consumers and naïve patients (p > 0.050). Adverse events were reported by 474 (16.73%) participants. CONCLUSIONS This study suggests that CBMPs are associated with an improvement in health-related quality of life in UK patients with chronic diseases. Treatment was tolerated well by most participants, but adverse events were more common in female and cannabis-naïve patients.
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Affiliation(s)
- Fabian Olsson
- Medical Cannabis Research Group, Department of Surgery and Cancer, Imperial College London, London, UK
| | - Simon Erridge
- Medical Cannabis Research Group, Department of Surgery and Cancer, Imperial College London, London, UK.,Department of Medicine, Sapphire Medical Clinics, London, UK
| | - James Tait
- Medical Cannabis Research Group, Department of Surgery and Cancer, Imperial College London, London, UK.,Department of Medicine, Sapphire Medical Clinics, London, UK
| | - Carl Holvey
- Department of Medicine, Sapphire Medical Clinics, London, UK
| | - Ross Coomber
- Department of Medicine, Sapphire Medical Clinics, London, UK.,Department of Trauma & Orthopaedics, St. George's Hospital NHS Trust, London, UK
| | - Sushil Beri
- Medical Cannabis Research Group, Department of Surgery and Cancer, Imperial College London, London, UK.,Department of Medicine, Sapphire Medical Clinics, London, UK
| | - Jonathan Hoare
- Medical Cannabis Research Group, Department of Surgery and Cancer, Imperial College London, London, UK.,Department of Medicine, Sapphire Medical Clinics, London, UK
| | - Shaheen Khan
- Department of Medicine, Sapphire Medical Clinics, London, UK.,Department of Palliative Medicine, Guy's & St. Thomas' NHS Foundation Trust, London, UK
| | - Mark W Weatherall
- Department of Medicine, Sapphire Medical Clinics, London, UK.,Department of Neurology, Buckinghamshire Healthcare NHS Trust, Amersham, UK
| | - Michael Platt
- Medical Cannabis Research Group, Department of Surgery and Cancer, Imperial College London, London, UK.,Department of Medicine, Sapphire Medical Clinics, London, UK
| | - James J Rucker
- Department of Medicine, Sapphire Medical Clinics, London, UK.,Department of Psychological Medicine, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK.,Centre for Affective Disorders, South London & Maudsley NHS Foundation Trust, London, UK
| | - Mikael H Sodergren
- Medical Cannabis Research Group, Department of Surgery and Cancer, Imperial College London, London, UK.,Department of Medicine, Sapphire Medical Clinics, London, UK
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3
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Erridge S, Holvey C, Coomber R, Hoare J, Khan S, Platt MW, Rucker JJ, Weatherall MW, Beri S, Sodergren MH. Clinical Outcome Data of Children Treated with Cannabis-Based Medicinal Products for Treatment Resistant Epilepsy - Analysis from the UK Medical Cannabis Registry. Neuropediatrics 2023; 54:174-181. [PMID: 36539215 PMCID: PMC10166640 DOI: 10.1055/a-2002-2119] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
BACKGROUND There is a paucity of high-quality evidence of the efficacy and safety of cannabis-based medicinal products in treatment of treatment-resistant epilepsy (TRE) in children. METHODS A case series of children (<18 years old) with TRE from the UK Medical Cannabis Registry was analyzed. Primary outcomes were ≥50% reduction in seizure frequency, changes in the Impact of Pediatric Epilepsy Score (IPES), and incidence of adverse events. RESULTS Thirty-five patients were included in the analysis. Patients were prescribed during their treatment with the following: CBD isolate oils (n = 19), CBD broad-spectrum oils (n = 17), and CBD/Δ9-THC combination therapy (n = 17). Twenty-three (65.7%) patients achieved a ≥50% reduction in seizure frequency. 94.1% (n = 16) of patients treated with CBD and Δ9-THC observed a ≥50% reduction in seizure frequency compared to 31.6% (n = 6) and 17.6% (n = 3) of patients treated with CBD isolates and broad-spectrum CBD products, respectively (p< 0.001). Twenty-six (74.3%) adverse events were reported by 16 patients (45.7%). The majority of these were mild (n = 12; 34.2%) and moderate (n = 10; 28.6%). CONCLUSION The results of this study demonstrate a positive signal of improved seizure frequency in children treated with Cannabis-based medicinal products (CBMPs) for TRE. Moreover, the results suggest that CBMPs are well-tolerated in the short term. The limitations mean causation cannot be determined in this open-label, case series.
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Affiliation(s)
- Simon Erridge
- Department of Surgery & Cancer, Imperial College London, London, United Kingdom.,Department of Medicine, Sapphire Medical Clinics, London, United Kingdom
| | - Carl Holvey
- Department of Medicine, Sapphire Medical Clinics, London, United Kingdom
| | - Ross Coomber
- Department of Medicine, Sapphire Medical Clinics, London, United Kingdom.,Department of Trauma & Orthopaedics, St Georges NHS Healthcare Trust, London, United Kingdom
| | - Jonathan Hoare
- Department of Surgery & Cancer, Imperial College London, London, United Kingdom.,Department of Medicine, Sapphire Medical Clinics, London, United Kingdom
| | - Shaheen Khan
- Department of Medicine, Sapphire Medical Clinics, London, United Kingdom.,Department of Palliative Medicine, Guy's & St Thomas' NHS Foundation Trust, London, United Kingdom
| | - Michael W Platt
- Department of Surgery & Cancer, Imperial College London, London, United Kingdom.,Department of Medicine, Sapphire Medical Clinics, London, United Kingdom
| | - James J Rucker
- Department of Medicine, Sapphire Medical Clinics, London, United Kingdom.,Department of Psychological Medicine, Institute of Psychiatry, Psychology & Neuroscience, Kings College London, London, United Kingdom.,Centre for Affective Disorders, South London & Maudsley NHS Foundation Trust, London, United Kingdom
| | - Mark W Weatherall
- Department of Medicine, Sapphire Medical Clinics, London, United Kingdom.,Department of Neurology, Buckinghamshire Healthcare NHS Trust, Amersham, United Kingdom
| | - Sushil Beri
- Department of Surgery & Cancer, Imperial College London, London, United Kingdom.,Department of Medicine, Sapphire Medical Clinics, London, United Kingdom
| | - Mikael H Sodergren
- Department of Surgery & Cancer, Imperial College London, London, United Kingdom.,Department of Medicine, Sapphire Medical Clinics, London, United Kingdom
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Ergisi M, Erridge S, Harris M, Kawka M, Nimalan D, Salazar O, Loupasaki K, Ali R, Holvey C, Coomber R, Usmani A, Sajad M, Beri S, Hoare J, Khan SA, Weatherall MW, Platt M, Rucker JJ, Sodergren MH. An Updated Analysis of Clinical Outcome Measures Across Patients From the UK Medical Cannabis Registry. Cannabis Cannabinoid Res 2022. [DOI: 10.1089/can.2021.0145] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Affiliation(s)
- Mehmet Ergisi
- Imperial College Medical Cannabis Research Group, Department of Surgery and Cancer, Imperial College London, London, United Kingdom
| | - Simon Erridge
- Imperial College Medical Cannabis Research Group, Department of Surgery and Cancer, Imperial College London, London, United Kingdom
- Sapphire Medical Clinics, London, United Kingdom
| | - Michael Harris
- Imperial College Medical Cannabis Research Group, Department of Surgery and Cancer, Imperial College London, London, United Kingdom
| | - Michal Kawka
- Imperial College Medical Cannabis Research Group, Department of Surgery and Cancer, Imperial College London, London, United Kingdom
| | - Devaki Nimalan
- Imperial College Medical Cannabis Research Group, Department of Surgery and Cancer, Imperial College London, London, United Kingdom
| | - Oliver Salazar
- Imperial College Medical Cannabis Research Group, Department of Surgery and Cancer, Imperial College London, London, United Kingdom
| | - Katerina Loupasaki
- Imperial College Medical Cannabis Research Group, Department of Surgery and Cancer, Imperial College London, London, United Kingdom
| | - Rayyan Ali
- Imperial College Medical Cannabis Research Group, Department of Surgery and Cancer, Imperial College London, London, United Kingdom
| | - Carl Holvey
- Sapphire Medical Clinics, London, United Kingdom
| | - Ross Coomber
- Sapphire Medical Clinics, London, United Kingdom
- St. George's Hospital NHS Trust, London, United Kingdom
| | - Azfer Usmani
- Sapphire Medical Clinics, London, United Kingdom
- Dartford and Gravesham NHS Trust, Kent, United Kingdom
| | - Mohammed Sajad
- Sapphire Medical Clinics, London, United Kingdom
- Dudley Group of Hospitals NHS Trust, West Midlands, United Kingdom
| | - Sushil Beri
- Imperial College Medical Cannabis Research Group, Department of Surgery and Cancer, Imperial College London, London, United Kingdom
- Sapphire Medical Clinics, London, United Kingdom
| | - Jonathan Hoare
- Imperial College Medical Cannabis Research Group, Department of Surgery and Cancer, Imperial College London, London, United Kingdom
- Sapphire Medical Clinics, London, United Kingdom
| | - Shaheen A. Khan
- Sapphire Medical Clinics, London, United Kingdom
- Guy's and St. Thomas' NHS Foundation Trust, London, United Kingdom
| | - Mark W. Weatherall
- Sapphire Medical Clinics, London, United Kingdom
- Buckinghamshire Healthcare NHS Trust, Amersham, United Kingdom
| | - Michael Platt
- Imperial College Medical Cannabis Research Group, Department of Surgery and Cancer, Imperial College London, London, United Kingdom
- Sapphire Medical Clinics, London, United Kingdom
| | - James J. Rucker
- Sapphire Medical Clinics, London, United Kingdom
- Department of Psychological Medicine, Institute of Psychiatry, Psychology and Neuroscience, Kings College London, London, United Kingdom
- South London and Maudsley NHS Foundation Trust, London, United Kingdom
| | - Mikael H. Sodergren
- Imperial College Medical Cannabis Research Group, Department of Surgery and Cancer, Imperial College London, London, United Kingdom
- Sapphire Medical Clinics, London, United Kingdom
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5
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Erridge S, Salazar O, Kawka M, Holvey C, Coomber R, Usmani A, Sajad M, Beri S, Hoare J, Khan S, Weatherall MW, Platt M, Rucker JJ, Sodergren MH. An initial analysis of the UK Medical Cannabis Registry: Outcomes analysis of first 129 patients. Neuropsychopharmacol Rep 2021; 41:362-370. [PMID: 33988306 PMCID: PMC8411316 DOI: 10.1002/npr2.12183] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Revised: 04/24/2021] [Accepted: 04/26/2021] [Indexed: 12/15/2022] Open
Abstract
AIM Cannabis-based medicinal products (CBMPs) are prescribed with increased frequency, despite a paucity of high-quality randomized controlled trials. The aim of this study is to analyze the early outcomes of the first series of patients prescribed CBMPs in the UK with respect to effects on health-related quality of life and clinical safety. METHODS A prospective case series was performed using the UK Medical Cannabis Registry. Primary outcomes were change in patient-reported outcomes measures (EQ-5D-5L, General Anxiety Disorder-7 (GAD-7) and Single-Item Sleep Quality Scale (SQS)) at 1 and 3 months from baseline. The secondary outcome was the incidence of adverse events. Statistical significance was defined by a P-value <.050. RESULTS There were 129 patients included in the final analysis with a mean age of 46.23 (±14.51) years. The most common indication was chronic pain of undefined etiology (n = 48; 37.2%). The median initial cannabidiol and (-)-trans-Δ⁹-tetrahydrocannabinol daily dose was 20.0 mg (Range: 0.0-768.0 mg) and 3.9 mg (Range: 0.0-660.0 mg), respectively. Statistically significant improvements in health-related quality of life were demonstrated at 1 and 3 months in GAD-7, SQS, EQ-5D-5L pain and discomfort subscale, EQ-5D-5L anxiety and depression subscale, EQ-VAS and EQ-5D-5L index values(P < .050). There were 31 (24.03%) total reported adverse events. CONCLUSION This study suggests that CBMP therapy may be associated with an improvement in health-related quality-of-life outcomes as self-reported by patients. CBMPs are also demonstrated to be relatively safe in the short to medium-term. These findings must be treated with caution given the limited scope of this initial analysis, with no placebo or an active comparator, with further research required.
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Affiliation(s)
- Simon Erridge
- Imperial College LondonLondonUK
- Sapphire Medical ClinicsLondonUK
| | | | | | | | - Ross Coomber
- Sapphire Medical ClinicsLondonUK
- St. George’s Hospital NHS TrustLondonUK
| | - Azfer Usmani
- Sapphire Medical ClinicsLondonUK
- Dartford and Gravesham NHS TrustKentUK
| | - Mohammed Sajad
- Sapphire Medical ClinicsLondonUK
- Dudley Group of Hospitals NHS TrustDudleyUK
| | - Sushil Beri
- Imperial College LondonLondonUK
- Sapphire Medical ClinicsLondonUK
| | - Jonathan Hoare
- Imperial College LondonLondonUK
- Sapphire Medical ClinicsLondonUK
| | - Shaheen Khan
- Sapphire Medical ClinicsLondonUK
- Guy’s & St Thomas’ NHS Foundation TrustLondonUK
| | - Mark W. Weatherall
- Sapphire Medical ClinicsLondonUK
- Buckinghamshire Healthcare NHS TrustAmershamUK
| | - Michael Platt
- Imperial College LondonLondonUK
- Sapphire Medical ClinicsLondonUK
| | - James J. Rucker
- Sapphire Medical ClinicsLondonUK
- Department of Psychological MedicineInstitute of Psychiatry, Psychology & NeuroscienceKings College LondonLondonUK
- South London & Maudsley NHS Foundation TrustLondonUK
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6
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Gosalakkal J, Hussain N, Parepalli S, Kanhere S, Beri S. A novel mutation in a family with complicated X linked spastic paraplegia. J Pediatr Neurol 2015. [DOI: 10.3233/jpn-2010-0445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Jayaprakash Gosalakkal
- Department of Pediatric Neurology, University Hospital of Leicester, NHS Trust, Leicester Royal Infirmary, Leicester, UK
| | - Nahin Hussain
- Department of Pediatric Neurology, University Hospital of Leicester, NHS Trust, Leicester Royal Infirmary, Leicester, UK
| | - Srinivas Parepalli
- Department of Pediatric Neurology, University Hospital of Leicester, NHS Trust, Leicester Royal Infirmary, Leicester, UK
| | - Sujata Kanhere
- Department of Pediatric Neurology, University Hospital of Leicester, NHS Trust, Leicester Royal Infirmary, Leicester, UK
| | - Sushil Beri
- Department of Pediatric Neurology, University Hospital of Leicester, NHS Trust, Leicester Royal Infirmary, Leicester, UK
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7
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Emmanuel J, Chow G, Beri S. Scrotal migration of lumbo-peritoneal shunt. J Pediatr Neurol 2015. [DOI: 10.3233/jpn-2011-0467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Joanne Emmanuel
- Department of Pediatric Neurology, Queens Medical Centre, Nottingham University Hospital NHS Trust, Nottingham, UK
| | - Gabriel Chow
- Department of Pediatric Neurology, Queens Medical Centre, Nottingham University Hospital NHS Trust, Nottingham, UK
| | - Sushil Beri
- Department of Pediatric Neurology, Queens Medical Centre, Nottingham University Hospital NHS Trust, Nottingham, UK
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Abstract
UNLABELLED Peripheral nerve injuries may have a number of causes, most commonly mechanical. We describe a case of a deep peroneal nerve palsy in an adolescent boy which coincided with a large growth spurt. Spontaneous recovery of full function was seen without intervention. CONCLUSION In the absence of any other causative factors, we believe that this growth spurt resulted in temporary compression of the deep peroneal nerve at the level of the knee producing transient neurapraxia.
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Affiliation(s)
- Kyriacos I Eleftheriou
- Department of Trauma and Orthopaedics, St Mary's Hospital, Praed Street, London, W2 1NY, UK,
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9
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Ganesan S, Beri S, Khan B, Hussain N. Voltage gated potassium channel antibodies positive autoimmune encephalopathy in a child: A case report and literature review of an under-recognized condition. Ann Indian Acad Neurol 2013; 16:593-6. [PMID: 24339586 PMCID: PMC3841607 DOI: 10.4103/0972-2327.120483] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2012] [Revised: 09/26/2012] [Accepted: 10/29/2012] [Indexed: 01/17/2023] Open
Abstract
Autoimmune limbic encephalitis (LE) associated with voltage gated potassium channel antibodies (VGKC-Abs) in children is more common than previously thought and is not always paraneoplastic. Non-neoplastic, autoimmune LE associated with VGKC-Abs has been described recently. However, only few case reports in children as the disease is predominantly described in the adult population. It is likely that this type of autoimmune encephalitis is currently under-diagnosed and hence, under-treated, especially in children. We present a 13-year-old previously fit and healthy African girl diagnosed with LE and we reviewed the literature for its current management.
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Affiliation(s)
- Subramanian Ganesan
- Department of Paediatric Neurology, Leicester Royal Infirmary, University Hospitals of Leicester NHS Trust, Leicester, United Kingdom
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10
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Khan A, Rattihalli R, Beri S, Dickinson F, Hussain N, Gosalakkal J. Cerebral proliferative angiopathy: a rare form of vascular malformation. J Paediatr Child Health 2013; 49:504-5. [PMID: 23724816 DOI: 10.1111/jpc.12233] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Arif Khan
- Department of Paediatric Neurology; Leicester Royal Infirmary; Leicester UK
| | - Rohini Rattihalli
- Department of Paediatric Neurology; Leicester Royal Infirmary; Leicester UK
| | - Sushil Beri
- Department of Paediatric Neurology; Leicester Royal Infirmary; Leicester UK
- Department of Paediatric Neurology; St Mary's Hospital; London United Kingdom
| | - Fiona Dickinson
- Department of Radiology; Leicester Royal Infirmary; Leicester UK
| | - Nahin Hussain
- Department of Paediatric Neurology; Leicester Royal Infirmary; Leicester UK
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11
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Khan A, Beri S, Baheerathan A, Balki A, Hussain N, Gosalakkal J. Globus pallidus high-signal lesions: A predominant MRI finding in children with neurofibromatosis type 1. Ann Indian Acad Neurol 2013; 16:53-6. [PMID: 23661963 PMCID: PMC3644782 DOI: 10.4103/0972-2327.107702] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2012] [Revised: 04/15/2012] [Accepted: 04/16/2012] [Indexed: 11/16/2022] Open
Abstract
Introduction: Lesions of the brain, recognized as unidentified bright objects (UBOs), are commonly observed as areas of increased T2-weighted signal intensity on magnetic resonance imaging (MRI) in children with neurofibromatosis type 1 (NF1). Identification of these lesions is not currently encompassed in the National Institute of Health (NIH) diagnostic criteria for NF1. Objective: We aimed to determine the prevalence of UBOs in children with NF1 and identify areas of the brain that are commonly affected by these lesions, allowing us to evaluate whether UBOs should be included in the diagnostic criteria for the diagnosis of NF1. Materials and Methods: We reviewed the cranial MRI scans of 22 children who had been diagnosed with sporadic or familial NF1 in accordance with the criteria established by NIH. UBOs were present in 81% of the children with NF1. Results: These lesions have a predilection for specific areas of the brain, including the globus pallidus (72%), cerebellum (66%), brainstem (27%) and cerebral hemispheres (16%). The prevalence of UBOs identified varied significantly with age and sex; they were infrequent in children less than 4 years of age but were common in those aged between 4 and 12 years of age. UBOs were more commonly seen in males (66.6%) compared with females (33.3%). Repeat MRI scan on a subset of these patients with UBOs did not show any significant changes despite a worsening in clinical symptoms. Conclusion and Discussion: We have shown that UBOs are a common finding in children with NF1, and are most prevalent between the ages of 4 and 12 years. Many sites of the brain are affected by these lesions, most notably the globus pallidus and the cerebellum. Further research must be conducted to elucidate the significance of UBOs in patients with NF1 and whether these lesions have any utility in the clinical detection of NF1.
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Affiliation(s)
- Arif Khan
- Department of Pediatric Neurology, Leicester Royal Infirmary, University Hospitals of Leicester NHS Trust, Leicester, United Kingdom
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12
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Mascheretti S, Bureau A, Battaglia M, Simone D, Quadrelli E, Croteau J, Cellino MR, Giorda R, Beri S, Maziade M, Marino C. An assessment of gene-by-environment interactions in developmental dyslexia-related phenotypes. Genes, Brain and Behavior 2012; 12:47-55. [DOI: 10.1111/gbb.12000] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Revised: 09/26/2012] [Accepted: 10/24/2012] [Indexed: 01/02/2023]
Affiliation(s)
- S. Mascheretti
- The Academic Centre for the study of Behavioural Plasticity; Vita-Salute San Raffaele University; Milan; 20132; Italy
| | | | | | - D. Simone
- Department of Child Psychiatry; Scientific Institute Eugenio Medea; Bosisio Parini; Lecco; 23842; Italy
| | - E. Quadrelli
- Department of Child Psychiatry; Scientific Institute Eugenio Medea; Bosisio Parini; Lecco; 23842; Italy
| | - J. Croteau
- Centre de Recherche de l'Institut universitaire en santé mentale de Québec; Québec; G1J 2 G3; Canada
| | - M. R. Cellino
- Centro Regionale di Riferimento per i Disturbi dell'Apprendimento - CRRDA, ULSS 20; Verona; 37122; Italy
| | - R. Giorda
- Molecular Biology Laboratory; Scientific Institute Eugenio Medea; Bosisio Parini; Lecco; 23842; Italy
| | - S. Beri
- Molecular Biology Laboratory; Scientific Institute Eugenio Medea; Bosisio Parini; Lecco; 23842; Italy
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Abstract
Iron deficiency anemia is a common pediatric problem affecting up to 25% children worldwide. It has been linked with cerebral venous sinus thrombosis in the literature. We describe a 9-month-old child who had severe iron deficiency anemia and developed acute venous sinus thrombosis associated with minor infection. Treatment with anticoagulation was partially successful with persistent thrombosis after 3 months. We reviewed the current literature highlighting the association of anemia as a risk factor for development of stroke in children.
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Affiliation(s)
- Sushil Beri
- Department of Paediatric Neurology, Leicester Royal Infirmary, University Hospitals of Leicester NHS Trust, Leicester, UK
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14
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Wadhwani M, Beri S, Saili A, Garg S. Homocystinuria masquerading as vitamin B12 deficiency. Nepal J Ophthalmol 2012; 4:326-8. [DOI: 10.3126/nepjoph.v4i2.6554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Background: Homocystinuria is a rare metabolic disorder charcterised by excess homocysteine in the urine. Vitamin B12 deficiency has diverse cutaneous, nervous and ophthalmic manifestations. Objective: To report a case of homocystinuria masquerading as vitamin B 12 deficiency. Case: We hereby are presenting an interesting case of a 4 year old boy who was being treated for Vitamin B 12 deficiency on the basis of history of delayed milestone, abdominal pain and hyperpigmentation of skin which was diagnosed as homocystinuria. Conclusion: It is important to carry out ophthalmological examination in every case of megaloblastic anemia if associated with blurring of vision and mental retardation.DOI: http://dx.doi.org/10.3126/nepjoph.v4i2.6554 Nepal J Ophthalmol 2012; 4 (8): 326-328
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Coomans W, Gelens L, Beri S, Danckaert J, Van der Sande G. Solitary and coupled semiconductor ring lasers as optical spiking neurons. Phys Rev E Stat Nonlin Soft Matter Phys 2011; 84:036209. [PMID: 22060477 DOI: 10.1103/physreve.84.036209] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2011] [Revised: 08/01/2011] [Indexed: 05/31/2023]
Abstract
We theoretically investigate the possibility of generating pulses in an excitable (asymmetric) semiconductor ring laser (SRL) using optical trigger pulses. We show that the phase difference between the injected field and the electric field inside the SRL determines the direction of the perturbation in phase space. Due to the folded shape of the excitability threshold, this has an important influence on the ability to cross it. A mechanism for exciting multiple consecutive pulses using a single trigger pulse (i.e., multipulse excitability) is revealed. We furthermore investigate the possibility of using asymmetric SRLs in a coupled configuration, which is a first step toward an all-optical neural network using SRLs as building blocks.
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Affiliation(s)
- W Coomans
- Applied Physics Research Group (APHY), Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussel, Belgium.
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Novara F, Beri S, Giorda R, Ortibus E, Nageshappa S, Darra F, Dalla Bernardina B, Zuffardi O, Van Esch H. Refining the phenotype associated with MEF2C haploinsufficiency. Clin Genet 2011; 78:471-7. [PMID: 20412115 DOI: 10.1111/j.1399-0004.2010.01413.x] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Recently, submicroscopic deletions of the 5q14.3 region have been described in patients with severe mental retardation (MR), stereotypic movements, epilepsy and cerebral malformations. Further delineation of a critical region of overlap in these patients pointed to MEF2C as the responsible gene. This finding was further reinforced by the identification of a nonsense mutation in a patient with a similar phenotype. In brain, MEF2C is essential for early neurogenesis, neuronal migration and differentiation. Here we present two additional patients with severe MR, autism spectrum disorder and epilepsy, carrying a very small deletion encompassing the MEF2C gene. This finding strengthens the role of this gene in severe MR, and enables further delineation of the clinical phenotype.
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Affiliation(s)
- F Novara
- Genetica Medica, Università di Pavia, Pavia, 27100 PV, Italy
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Beri S, Chandratre S, Chow G. Familial idiopathic intracranial hypertension with variable phenotype. Eur J Paediatr Neurol 2011; 15:81-3. [PMID: 20207561 DOI: 10.1016/j.ejpn.2010.02.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2009] [Revised: 02/10/2010] [Accepted: 02/10/2010] [Indexed: 11/26/2022]
Abstract
Familial occurrence of Idiopathic intracranial hypertension has been rarely reported in the literature. Idiopathic intracranial hypertension, both with and without papilloedema is only described in two families before, though one had a probable diagnosis. We report a family of mother and her two daughters. A 37 year old woman was diagnosed with idiopathic intracranial hypertension. Her 7 year old, younger daughter presented a year later with similar symptoms. She did not respond to medical treatment and required Lumbo-peritoneal shunt, Ventriculo-peritoneal shunt and bilateral sub-temporal decompression. Her elder daughter later presented with headaches and idiopathic intracranial hypertension without papilloedema was diagnosed at the age of 13 years. Further insight into the patterns of inheritance is required and other family members should be offered screening, even if papilloedema is not present.
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Affiliation(s)
- Sushil Beri
- Department of Paediatric Neurology, Queens Medical Centre, Nottingham University Hospital NHS Trust, Nottingham, UK.
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Chen D, Kapre S, Goel A, Suresh K, Beri S, Hickling J, Jensen J, Lal M, Preaud J, LaForce M, Kristensen D. Thermostable formulations of a hepatitis B vaccine and a meningitis A polysaccharide conjugate vaccine produced by a spray drying method. Vaccine 2010; 28:5093-9. [DOI: 10.1016/j.vaccine.2010.04.112] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2010] [Revised: 04/28/2010] [Accepted: 04/30/2010] [Indexed: 11/26/2022]
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Beri S, Gosalakkal JA, Hussain N, Balky AP, Parepalli S. Idiopathic intracranial hypertension without papilledema. Pediatr Neurol 2010; 42:56-8. [PMID: 20004864 DOI: 10.1016/j.pediatrneurol.2009.07.021] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2009] [Revised: 06/11/2009] [Accepted: 07/27/2009] [Indexed: 11/26/2022]
Abstract
Idiopathic intracranial hypertension is characterized by high cerebrospinal fluid pressure with no underlying structural or systemic cause. Idiopathic intracranial hypertension without papilledema, although well-described in adults, is rarely reported in the pediatric population. The usual presentation is similar to that of chronic daily headache, with some features of migraine. However, treatment modalities are different, and specific therapy can lead to significant improvement in symptoms. We describe six children with chronic daily headache, who were diagnosed with idiopathic intracranial hypertension without papilledema. The response to medical management was variable. One child required a lumboperitoneal shunt for persistent signs, with good surgical outcome.
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Affiliation(s)
- Sushil Beri
- Department of Paediatric Neurology, Leicester Royal Infirmary, University Hospitals of Leicester, Leicester, United Kingdom.
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Rajabally YA, Beri S, Bankart J. Electrophysiological markers of large fibre sensory neuropathy: a study of sensory and motor conduction parameters. Eur J Neurol 2009; 16:1053-9. [DOI: 10.1111/j.1468-1331.2009.02651.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Gelens L, Beri S, Van der Sande G, Mezosi G, Sorel M, Danckaert J, Verschaffelt G. Exploring multistability in semiconductor ring lasers: theory and experiment. Phys Rev Lett 2009; 102:193904. [PMID: 19518954 DOI: 10.1103/physrevlett.102.193904] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2009] [Indexed: 05/27/2023]
Abstract
We report the first experimental observation of multistable states in a single-longitudinal mode semiconductor ring laser. We show how the operation of the device can be steered to either monostable, bistable, or multistable dynamical regimes in a controlled way. We observe that the dynamical regimes are organized in well-reproducible sequences that match the bifurcation diagrams of a two-dimensional model. By analyzing the phase space in this model, we predict how the stochastic transitions between multistable states take place and confirm it experimentally.
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Affiliation(s)
- L Gelens
- Department of Applied Physics and Photonics, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
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Rajabally YA, Simpson BS, Beri S, Bankart J, Gosalakkal JA. Epidemiologic variability of chronic inflammatory demyelinating polyneuropathy with different diagnostic criteria: Study of a UK population. Muscle Nerve 2009; 39:432-8. [DOI: 10.1002/mus.21206] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Gelens L, Van der Sande G, Beri S, Danckaert J. Phase-space approach to directional switching in semiconductor ring lasers. Phys Rev E Stat Nonlin Soft Matter Phys 2009; 79:016213. [PMID: 19257128 DOI: 10.1103/physreve.79.016213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2008] [Indexed: 05/27/2023]
Abstract
We show that a topological investigation of the phase space of a semiconductor ring laser can be used to devise switching schemes which are alternative to optical pulse injection of counterpropagating light. To provide physical insight in these switching mechanisms, a full bifurcation analysis and an investigation of the topology is performed on a two-dimensional asymptotic model. Numerical simulations confirm the topological predictions.
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Affiliation(s)
- L Gelens
- Department of Applied Physics and Photonics, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussel, Belgium
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Beri S, Gelens L, Mestre M, Van der Sande G, Verschaffelt G, Scirè A, Mezosi G, Sorel M, Danckaert J. Topological insight into the non-arrhenius mode hopping of semiconductor ring lasers. Phys Rev Lett 2008; 101:093903. [PMID: 18851614 DOI: 10.1103/physrevlett.101.093903] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2008] [Indexed: 05/26/2023]
Abstract
We investigate both theoretically and experimentally the stochastic switching between two counterpropagating lasing modes of a semiconductor ring laser. Experimentally, the residence time distribution cannot be described by a simple one-parameter Arrhenius exponential law and reveals the presence of two different mode-hop scenarios with distinct time scales. In order to elucidate the origin of these two time scales, we propose a topological approach based on a two-dimensional dynamical system.
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Affiliation(s)
- S Beri
- Department of Applied Physics and Photonics, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
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Kramer EM, Lewandowski M, Beri S, Bernard J, Borkowski M, Borkowski MH, Burchfield LA, Mathisen B, Normanly J. Auxin Gradients Are Associated with Polarity Changes in Trees. Science 2008; 320:1610. [DOI: 10.1126/science.1156130] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Battaglia M, Zanoni A, Giorda R, Pozzoli U, Citterio A, Beri S, Ogliari A, Nobile M, Marino C, Molteni M. Effect of the catechol-O-methyltransferase val158met genotype on children?s early phases of facial stimuli processing. Genes Brain Behav 2007; 6:364-74. [PMID: 16939639 DOI: 10.1111/j.1601-183x.2006.00265.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The ability to process and identify human faces matures early in life, is universal and is mediated by a distributed neural system. The temporal dynamics of this cognitive-emotional task can be studied by cerebral visual event-related potentials (ERPs) that are stable from midchildhood onwards. We hypothesized that part of individual variability in the parameters of the N170, a waveform that specifically marks the early, precategorical phases of human face processing, could be associated with genetic variation at the functional polymorphism of the catechol-O-methyltransferase (val(158)met) gene, which influences information processing, cognitive control tasks and patterns of brain activation during passive processing of human facial stimuli. Forty-nine third and fourth graders underwent a task of implicit processing of other children's facial expressions of emotions while ERPs were recorded. The N170 parameters (latency and amplitude) were insensitive to the type of expression, stimulus repetition, gender or school grade. Although limited by the absence of met- homozygotes among boys, data showed shorter N170 latency associated with the presence of 1-2 met158 alleles, and family-based association tests (as implemented in the PBAT version 2.6 software package) confirmed the association. These data were independent of the serotonin transporter promoter polymorphism and the N400 waveform investigated in the same group of children in a previous study. Some electrophysiological features of face processing may be stable from midchildhood onwards. Different waveforms generated by face processing may have at least partially independent genetic architectures and yield different implications toward the understanding of individual differences in cognition and emotions.
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Affiliation(s)
- M Battaglia
- Department of Psychology, Vita-Salute San Raffaele University at the Istituto Scientifico San Raffaele, Milan, Italy.
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Gimelli G, Giorda R, Beri S, Gimelli S, Zuffardi O. A large analphoid invdup(3)(q22.3qter) marker chromosome characterized by array-CGH in a child with malformations, mental retardation, ambiguous genitalia and Blaschko's lines. Eur J Med Genet 2007; 50:264-73. [PMID: 17567547 DOI: 10.1016/j.ejmg.2007.04.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2007] [Accepted: 04/26/2007] [Indexed: 11/26/2022]
Abstract
We report a new case of mosaic chromosome 3-derived marker chromosome, present in fibroblasts but not in lymphocytes, found in a child with malformations, mental retardation and ambiguous genitalia. Cytogenetic and molecular analysis showed that the supernumerary invdup(3)(q22.3qter) chromosome was negative at FISH with alpha satellite probe. The presence of a functional neocentromere was confirmed by immunofluorescence with antibodies to centromere proteins (CENPs). Definition of the marker breakpoints has been done through array-CGH. The skin of the patient presented dyschromic areas ordered along Blaschko's lines. The invdup(3q) marker chromosome was present only in fibroblasts from the dark skin biopsy, while lymphocytes and fibroblasts from the normal skin showed a normal male karyotype. Expression of the HPS3 gene (MIM: 606118) was more than two times higher in dark skin fibroblasts. Neocentromeres are most often observed on chromosomal arm fragments that have separated from an endogenous centromere, and therefore actually confer mitotic stability to what would have been acentric fragments. To our knowledge, this invdup(3q) analphoid marker is the largest among the several reported so far. Parental origin and possible mode of formation have been defined by DNA polymorphisms studies. The size of the duplicated marker chromosome and its frequency and tissue distribution may be relevant to the severity of the propositus' phenotype.
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Affiliation(s)
- G Gimelli
- Laboratorio di Citogenetica, Istituto G. Gaslini, Largo G. Gaslini 5, 16148 Genova, Italy.
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Yousefi M, Barbarin Y, Beri S, Bente EAJM, Smit MK, Nötzel R, Lenstra D. New role for nonlinear dynamics and chaos in integrated semiconductor laser technology. Phys Rev Lett 2007; 98:044101. [PMID: 17358775 DOI: 10.1103/physrevlett.98.044101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2006] [Indexed: 05/14/2023]
Abstract
Using an integrated colliding-pulse mode-locked semiconductor laser, we demonstrate the existence of nonlinear dynamics and chaos in photonic integrated circuits (PICs) by demonstrating a period-doubling transition into chaos. Unlike their stand-alone counterparts, the dynamics of PICs are more stable over the lifetime of the system, reproducible from batch to batch and on faster time scales due to the small sizes of PICs.
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Affiliation(s)
- M Yousefi
- COBRA Research Institute, Technische Universiteit Eindhoven, The Netherlands.
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Beri S, Mannella R, Luchinsky DG, Silchenko AN, McClintock PVE. Solution of the boundary value problem for optimal escape in continuous stochastic systems and maps. Phys Rev E Stat Nonlin Soft Matter Phys 2005; 72:036131. [PMID: 16241539 DOI: 10.1103/physreve.72.036131] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2005] [Indexed: 05/05/2023]
Abstract
Topologies of invariant manifolds and optimal trajectories are investigated in stochastic continuous systems and maps. A topological method is introduced that simplifies the solution of boundary value problems: The activation energy is calculated as a function of a set of parameters characterizing the initial conditions of the escape path. The method is applied explicitly to compute the optimal escape path and the activation energy for a variety of dynamical systems and maps.
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Affiliation(s)
- S Beri
- Department of Physics, Lancaster University, Lancaster LA1 4YB, United Kingdom
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Silchenko AN, Beri S, Luchinsky DG, McClintock PVE. Fluctuational transitions across different kinds of fractal basin boundaries. Phys Rev E Stat Nonlin Soft Matter Phys 2005; 71:046203. [PMID: 15903766 DOI: 10.1103/physreve.71.046203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2004] [Revised: 11/29/2004] [Indexed: 05/02/2023]
Abstract
We study fluctuational transitions in discrete and continuous dynamical systems that have two coexisting attractors in phase space, separated by a fractal basin boundary which may be either locally disconnected or locally connected. Theoretical and numerical evidence is given to show that, in each case, the transition occurs via a unique accessible point on the boundary, both in discrete systems and in flows. The complicated structure of the escape paths inside the locally disconnected fractal basin boundary is determined by a hierarchy of homoclinic points. The interrelation between the mechanism of transitions and the hierarchy is illustrated by consideration of fluctuational transitions in dynamical systems demonstrating "fractal-fractal" basin boundary metamorphosis at some value of a control parameter. The most probable escape path from an attractor, which can be either regular or chaotic, is found for each type of boundary using both statistical analysis of fluctuational trajectories and the Hamiltonian theory of fluctuations.
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Affiliation(s)
- A N Silchenko
- Department of Physics, Lancaster University, Lancaster LA1 4YB, United Kingdom
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Beri S, Mannella R, McClintock PVE. Dynamic importance sampling for the escape problem in nonequilibrium systems: observation of shifts in optimal paths. Phys Rev Lett 2004; 92:020601. [PMID: 14753926 DOI: 10.1103/physrevlett.92.020601] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2003] [Indexed: 05/24/2023]
Abstract
The activation problem is investigated in two-dimensional nonequilibrium systems. A numerical approach based on dynamic importance sampling (DIMS) is introduced. DIMS accelerates the simulations and allows the investigation to access noise intensities that were previously forbidden. The escape path is observed to be shifted compared to a heteroclinic trajectory calculated in the limit of zero-noise intensity. A theory to account for such shifts is presented and shown to agree with the simulations for a wide range of noise intensities.
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Affiliation(s)
- S Beri
- Department of Physics, Lancaster University, Lancaster LA1 4YB, United Kingdom
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Silchenko AN, Beri S, Luchinsky DG, McClintock PVE. Fluctuational transitions through a fractal basin boundary. Phys Rev Lett 2003; 91:174104. [PMID: 14611351 DOI: 10.1103/physrevlett.91.174104] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2003] [Indexed: 05/24/2023]
Abstract
Fluctuational transitions between two coexisting chaotic attractors, separated by a fractal basin boundary, are studied in a discrete dynamical system. It is shown that the transition mechanism is determined by a hierarchy of homoclinic points. The most probable escape path from a chaotic attractor to the fractal boundary is found using both statistical analyses of fluctuational trajectories and the Hamiltonian theory of fluctuations.
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Affiliation(s)
- A N Silchenko
- Department of Physics, Lancaster University, Lancaster LA1 4YB, U.K
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Bandrivskyy A, Beri S, Luchinsky DG, Mannella R, McClintock PVE. Fast monte carlo simulations and singularities in the probability distributions of nonequilibrium systems. Phys Rev Lett 2003; 90:210201. [PMID: 12786539 DOI: 10.1103/physrevlett.90.210201] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2002] [Indexed: 05/24/2023]
Abstract
A numerical technique is introduced that reduces exponentially the time required for Monte Carlo simulations of nonequilibrium systems. Results for the quasistationary probability distribution in two model systems are compared with the asymptotically exact theory in the limit of extremely small noise intensity. Singularities of the nonequilibrium distributions are revealed by the simulations.
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Affiliation(s)
- A Bandrivskyy
- Department of Physics, Lancaster University, Lancaster LA1 4YB, United Kingdom
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Biswas NR, Gupta SK, Das GK, Kumar N, Mongre PK, Haldar D, Beri S. Evaluation of Ophthacare eye drops--a herbal formulation in the management of various ophthalmic disorders. Phytother Res 2001; 15:618-20. [PMID: 11746845 DOI: 10.1002/ptr.896] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
An open prospective multicentre clinical trial was conducted in patients suffering from various ophthalmic disorders namely, conjunctivitis, conjunctival xerosis (dry eye), acute dacryocystitis, degenerative conditions (pterygium or pinguecula) and postoperative cataract patients with a herbal eye drop preparation (Ophthacare) containing basic principles of different herbs which have been conventionally used in the Ayurvedic system of medicine since time immemorial. These include Carum copticum, Terminalia belirica, Emblica officinalis, Curcuma longa, Ocimum sanctum, Cinnamomum camphora, Rosa damascena and meldespumapum. These herbs reportedly possess antiinfective and antiinflammatory properties. The present study was undertaken to elucidate the role of this herbal product in a variety of eye ailments. Side effects, if any, were noted during the study. An improvement was observed with the treatment of the herbal eye drop treatment in most cases. There were no side effects observed during the course of the study and the eye drop was well tolerated by the patients. The herbal eye drop Ophthacare has a useful role in a variety of infective, inflammatory and degenerative ophthalmic disorders.
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Affiliation(s)
- N R Biswas
- All India Institute of Medical Sciences, New Delhi 110029, India
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Beri S, Biswas NR, Shende DR, Das GK, Pandey RM, Ghose S. Injectable centbucridine and lidocaine hydrochloride for intraocular surgery. Ophthalmic Surg Lasers 1997; 28:1027-9. [PMID: 9427994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- S Beri
- Division of Ocular Pharmacology, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
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Biswas NR, Beri S, Das GK, Mongre PK. Comparative double blind multicentric randomised placebo controlled clinical trial of a herbal preparation of eye drops in some ocular ailments. J Indian Med Assoc 1996; 94:101-2. [PMID: 8810206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A double masked placebo controlled multicentric randomised clinical trial was conducted in 157 patients suffering from different eye ailments namely, cataract, dry eye syndrome, ocular asthenia, refractive errors and allergic conjunctivitis with a herbal eye drop preparation and placebo. In both dry eye syndrome and ocular asthenia the herbal eye drop preparation was found better than placebo. In a few cases of cataract, the vision seems to be improved. In early myopia it seems to correct the refractive errors while in high myopic conditions it controlled the progressive deteriorations. Subjective improvements were also noted with hypermetropia, presbyopia and astigmatism. Its healing capacity in allergic conjunctivitis was certainly better than placebo. It had no short term or long term side-effects. It is considered to be a useful drug in all conditions studied.
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Affiliation(s)
- N R Biswas
- Dr RP Centre for Ophthalmic Sciences, AIIMS, New Delhi
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Bobde V, Beri S, Rawale S, Satyanarayana C, Durani S. A single point chiral inversion that selforganizes a randomcoil peptide. Apolar solvent conformation of Boc-(L\D)-Glu-Ala-Leu-LysNHMe. Tetrahedron 1995. [DOI: 10.1016/0040-4020(95)00047-c] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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