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Anning KL, Langley K, Hobson C, De Sonneville L, Van Goozen SHM. Inattention symptom severity and cognitive processes in children at risk of ADHD: the moderating role of separation anxiety. Child Neuropsychol 2024; 30:264-288. [PMID: 36960813 DOI: 10.1080/09297049.2023.2190964] [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] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 02/24/2023] [Indexed: 03/25/2023]
Abstract
Impairments in cognitive processes and their associations with dimensional measures of inattention, hyperactivity-impulsivity and anxiety were examined in children at risk of Attention-Deficit Hyperactivity Disorder. Children referred by teachers for exhibiting ADHD-type problems (n = 116; 43 meeting full diagnostic criteria for ADHD; 4-8 years) completed computerized tasks measuring episodic memory, response inhibition, visuomotor control and sustained attention, while parents were interviewed (DAWBA) to assess ADHD and anxiety symptoms. Of the 116 children assessed, 72% exhibited impaired cognitive processes; 47% had impaired visuomotor control, 37% impaired response inhibition, and 35% had impaired episodic memory. Correlational and hierarchical regression analyses using our final analytic sample (i.e., children who completed all cognitive tasks and a vocabulary assessment, n = 114) showed that poorer task performance and greater within-subject variability were significantly associated with more severe inattention symptoms but not with hyperactivity-impulsivity severity. Symptoms of separation anxiety, which were reported in over half of the sample, moderated associations between inattention and episodic memory, and between inattention and inhibition. Only children without separation anxiety showed significant correlations between ADHD symptoms and poor performance. However, separation anxiety had no moderating effect on associations between inattention and visuomotor control or sustaining attention. Children exhibiting signs of ADHD show impairments across a range of cognitive tasks. Further research to improve our understanding of these processes may be useful in the development of early interventions. Our results suggest that separation anxiety should be taken into account when considering interventions to address emerging neuropsychological deficits associated with this disorder.
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Affiliation(s)
- Kate L Anning
- School of Psychology, Cardiff University, Cardiff, UK
| | - Kate Langley
- School of Psychology, Cardiff University, Cardiff, UK
| | | | - Leo De Sonneville
- Department of Clinical Neurodevelopmental Studies, Leiden University, Leiden, The Netherlands
| | - Stephanie H M Van Goozen
- School of Psychology, Cardiff University, Cardiff, UK
- Department of Clinical Neurodevelopmental Studies, Leiden University, Leiden, The Netherlands
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Ferguson C, Hobson C, Hedge C, Waters C, Anning K, van Goozen S. Disentangling the relationships between motor control and cognitive control in young children with symptoms of ADHD. Child Neuropsychol 2024; 30:289-314. [PMID: 36946244 DOI: 10.1080/09297049.2023.2190965] [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: 12/06/2022] [Accepted: 02/28/2023] [Indexed: 03/23/2023]
Abstract
Children with ADHD experience difficulties with motor and cognitive control. However, the relationships between these symptoms are poorly understood. As a step toward improving treatment, this study investigated associations between specific aspects of motor control and cognitive control in children with varying levels of hyperactive-impulsive symptoms. A heterogeneous sample of 255 children of 4 to 10 years of age (median = 6.50, MAD = 1.36) completed a battery of tests probing motor generation, visuomotor fluency, visuomotor flexibility, cognitive inhibition, verbal and visuospatial working memory, and cognitive flexibility. Their caregivers were interviewed regarding their hyperactive-impulsive symptoms. 25.9% of the main sample met diagnostic criteria for ADHD. Multiple linear regression analysis was used to determine whether specific aspects of motor control were associated with specific aspects of cognitive control, and whether any associations were moderated by hyperactive-impulsive symptoms. Additionally, cognitive modeling (the drift diffusion model approximated with EZ-DM) was used to understand performance on a cognitive inhibition task. Visuomotor fluency was significantly associated with cognitive inhibition. Visuomotor flexibility was significantly associated with cognitive flexibility. There were no significant moderation effects. Cognitive modeling was inconclusive. In conclusion, the ability to fluently perform visually guided continuous movement is linked with the ability to inhibit the effects of distracting information. The ability to spontaneously use visual information to flexibly alter motor responses is related to the ability to cognitively shift from one frame of mind to another. These relationships appear to be quantitatively and qualitatively similar across the childhood hyperactive-impulsive continuum as rated by parents.
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Affiliation(s)
- Cameron Ferguson
- School of Psychological Science, University of Bristol, Bristol, United Kingdom
- Community Neurological Rehabilitation Service, Aneurin Bevan University Health Board, NHS Wales, Newport, United Kingdom
| | - Christopher Hobson
- South Wales Doctoral Programme in Clinical Psychology, Cardiff and Vale University Health Board, NHS Wales, Cardiff, United Kingdom
- Neurodevelopment Assessment Unit, Cardiff University, Cardiff, United Kingdom
| | - Craig Hedge
- School of Psychology, Aston University, Aston, United Kingdom
| | - Cerith Waters
- South Wales Doctoral Programme in Clinical Psychology, Cardiff and Vale University Health Board, NHS Wales, Cardiff, United Kingdom
- Neurodevelopment Assessment Unit, Cardiff University, Cardiff, United Kingdom
| | - Kate Anning
- Neurodevelopment Assessment Unit, Cardiff University, Cardiff, United Kingdom
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Scoberg B, Hobson C, van Goozen S. Psychometric Properties and Validity of the Screen for Child Anxiety Related Emotional Disorders: Parent Version (SCARED-P) in an Early Childhood Sample. Assessment 2024:10731911231225203. [PMID: 38258550 DOI: 10.1177/10731911231225203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
The Screen for Child Anxiety Related Emotional Disorders: Parent Version (SCARED-P) was originally developed for use in middle childhood and adolescence. The present study examined the psychometric properties and validity of the SCARED-P in an early childhood sample (predominantly aged 4-7 years). The 41-item version of the SCARED-P was administered to the parents of 233 children (mean age = 6.31 years, SD = 1.08; females = 34.3%). Confirmatory factor analysis provided mixed support for the original five-factor model of the SCARED-P. The SCARED-P demonstrated good to excellent internal consistency (total α = .94, subscale α = .68-.89), and good construct validity with the Child Behavior Checklist, Strengths and Difficulties Questionnaire, and the Developmental and Well-being Assessment. These findings indicate overall initial support for the SCARED-P's utility as a measure of anxiety in early childhood, but further psychometric and validation studies are needed in larger community-based samples of young children.
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Anning KL, Langley K, Hobson C, van Goozen SHM. Cool and hot executive function problems in young children: linking self-regulation processes to emerging clinical symptoms. Eur Child Adolesc Psychiatry 2024:10.1007/s00787-023-02344-z. [PMID: 38183461 DOI: 10.1007/s00787-023-02344-z] [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] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Accepted: 11/28/2023] [Indexed: 01/08/2024]
Abstract
Self-regulation (SR) difficulties are implicated in a wide range of disorders which develop in childhood, including attention deficit hyperactivity disorder (ADHD), oppositional defiance disorder (ODD), anxiety and depression. However, the integration of the existing research evidence is challenging because of varying terminology and the wide range of tasks used, as well as the heterogeneity and comorbidity within and across diagnostic categories. The current study used the Research Domain Criteria (RDoC) framework to guide the examination of different SR processes in young children showing a wide range of symptomatology. Children (aged 4-8) referred by teachers for moderate-to-high conduct, hyperactivity and/or emotional problems at school (assessed using the Strengths and Difficulties Questionnaire (SDQ) subscales; n = 212), and children in SDQ typical ranges (n = 30) completed computerised cognitive control and decision-making tasks. Parents completed questionnaires to assess ADHD, ODD, anxiety and depression symptoms (n = 191). Compared to children with no teacher-reported difficulties, those with moderate-to-high problems showed poorer visuomotor control and decision-making. A factor analysis revealed that task variables adhered to RDoC dimensions and predicted variance in specific disorders: difficulties in cognitive control predicted ADHD symptoms, low reward-seeking was associated with depression and high reward-seeking was associated with ODD. This study highlights how the assessment of cognitive processes positioned within the RDoC framework can inform our understanding of disorder-specific and transdiagnostic difficulties in SR which are associated with diverse clinical symptoms in children.
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Affiliation(s)
- Kate L Anning
- School of Psychology, Cardiff University, Cardiff, UK.
- Department of Psychology, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom.
| | - Kate Langley
- School of Psychology, Cardiff University, Cardiff, UK
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Howe-Davies H, Hobson C, Waters C, van Goozen SHM. Emotional and socio-cognitive processing in young children with symptoms of anxiety. Eur Child Adolesc Psychiatry 2023; 32:2077-2088. [PMID: 35861892 PMCID: PMC10533571 DOI: 10.1007/s00787-022-02050-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Accepted: 07/10/2022] [Indexed: 11/24/2022]
Abstract
Many children with anxiety disorders exhibit significant and persistent impairments in their social and interpersonal functioning. Two components essential for successful social interaction are empathy and theory of mind (ToM). Both constructs develop rapidly in childhood, but no study has simultaneously examined these skills in young children with emerging mental health problems, including those with symptoms of anxiety. This study investigated empathy and ToM in children with anxiety symptomatology and examined their relationship with anxiety severity. A cross-sectional study was carried out with 174 children aged 4-8 years with emerging mental health difficulties who were referred by school teachers for an assessment because of emotional, cognitive, or behavioural problems at school. Participants completed empathy and ToM tasks. Parents were interviewed and rated children's emotional and behavioural problems. Correlational analyses indicated that elevated anxiety was associated with better cognitive ToM and worse affective empathy; there were no associations between anxiety and either cognitive empathy or affective ToM. Subsequent regression analyses demonstrated that whilst enhanced cognitive ToM was explained by age and verbal IQ, anxiety symptoms uniquely predicted impaired affective empathy. These results indicate that children with symptoms of anxiety have difficulty in sharing in other people's emotions. As a result, they may find it difficult to behave in socially adequate ways in interactions with others that involve affective sharing. These findings encourage the use of early and targeted interventions that improve affective empathy development in children with anxiety symptoms.
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Affiliation(s)
| | | | | | - Stephanie H M van Goozen
- School of Psychology, Cardiff University, Wales, UK.
- Department of Clinical Child and Adolescent Studies, Leiden University, Leiden, Netherlands.
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Anning KL, Langley K, Hobson C, Van Goozen SHM. Dimensional associations between executive function processes and symptoms of ADHD, ASD, oppositional defiance and anxiety in young school-referred children. Cortex 2023; 167:132-147. [PMID: 37557009 DOI: 10.1016/j.cortex.2023.06.005] [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: 12/13/2022] [Revised: 04/28/2023] [Accepted: 06/20/2023] [Indexed: 08/11/2023]
Abstract
Executive function (EF) difficulties are implicated in Neurodevelopmental Disorders (NDDs), such as Autism Spectrum Disorder (ASD) and Attention Deficit Hyperactivity Disorder (ADHD). Because NDDs are highly comorbid and frequently co-occur with additional clinical problems, it is unclear how specific EF problems are associated with symptoms of ASD and ADHD, whilst accounting for co-occurring anxiety or oppositional defiance disorder (ODD) symptoms. The current study utilised a large sample of young children (n = 438, aged 4-8) referred to Cardiff University's Neurodevelopment Assessment Unit (NDAU) by teachers for cognitive and/or socio-emotional problems. As part of the referral process, the teachers completed the Strengths and Difficulties Questionnaire (SDQ), which revealed that most children displayed moderate to high hyperactivity (86%) and prosocial (73%) problems, as well as high levels of symptoms in other clinical domains (41% emotional, 61% conduct and 68% peer problems). Children completed tasks to assess episodic memory, cognitive inhibition, cognitive flexibility and visuomotor control, whilst parents completed questionnaires to measure symptoms of ASD, ADHD, anxiety and ODD. Dimensional analyses showed that poorer cognitive inhibition and visuospatial episodic memory were significantly associated with ADHD symptoms, whereas cognitive flexibility was negatively associated with ODD symptoms. Having more ASD symptoms was associated with fewer cognitive inhibition problems, whereas anxiety was associated with better cognitive flexibility. Our approach to assessment and analysis shows that specific cognitive processes are associated with distinct neurodevelopmental and clinical symptoms, which is ultimately relevant to early identification of and intervention for young children at risk of cognitive and/or socio-emotional problems.
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Affiliation(s)
- Kate L Anning
- School of Psychology, Cardiff University, Cardiff, UK.
| | - Kate Langley
- School of Psychology, Cardiff University, Cardiff, UK
| | | | - Stephanie H M Van Goozen
- School of Psychology, Cardiff University, Cardiff, UK; Department of Clinical Neurodevelopmental Studies, Leiden University, Leiden, the Netherlands.
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Adegboye D, Lennon J, Batterbee O, Thapar A, Collishaw S, Shelton K, Langley K, Hobson C, Higgins A, van Goozen S. Understanding de novo onset of anxiety during COVID-19: Pre-pandemic socio-emotional functioning in vulnerable children. JCPP Adv 2022; 2:e12076. [PMID: 35942432 PMCID: PMC9348403 DOI: 10.1002/jcv2.12076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Accepted: 04/10/2022] [Indexed: 11/20/2022] Open
Abstract
Background There is a need to understand and mitigate the psychological impacts of the COVID-19 pandemic for children known to be vulnerable. Data from prior to the pandemic are required to provide robust assessments of the socio-emotional impacts of COVID-19 and identify those who are more vulnerable. Method This study capitalises on an ongoing UK study of primary school children (4-8 years) identified prior to the pandemic as "at risk" for mental health problems by teachers. We collected mental health and social-emotional functioning data prior to the pandemic (Time 1) and re-assessed this cohort (N = 143) via researcher-led videocalls during lockdown (Time 2, summer 2020) and post-lockdown, 12 months later (Time 3; summer 2021). Results Mental health problems, particularly clinically significant anxiety, increased from 34% to 43% during lockdown and to 48% post-lockdown. Parental mental health difficulties (anxiety and depression) were prevalent during lockdown (40%) but had decreased 1 year later (20%). Children who developed clinically significant anxiety during the pandemic had impaired socio-emotional functioning at Time 1 (i.e., impaired emotion recognition, low self-esteem and social problems) and a high proportion (44%) had no contact with any peers during lockdown, which may have contributed to their anxiety, especially their school anxiety. Conclusion The pandemic appears to have exacerbated anxiety in already vulnerable children. A profile of socio-emotional problems identified a group of children who developed significant anxieties during the pandemic. These socio-emotional processes can be targeted for intervention to mitigate the negative mental health consequences of the pandemic and contribute to resilience in children.
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Affiliation(s)
| | | | | | - Anita Thapar
- School of Medicine Cardiff University Cardiff UK
| | | | | | - Kate Langley
- School of Psychology Cardiff University Cardiff UK
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Adegboye D, Williams F, Collishaw S, Shelton K, Langley K, Hobson C, Burley D, van Goozen S. Understanding why the COVID-19 pandemic-related lockdown increases mental health difficulties in vulnerable young children. JCPP Adv 2021; 1:e12005. [PMID: 34485985 PMCID: PMC8250118 DOI: 10.1111/jcv2.12005] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [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: 01/28/2021] [Revised: 02/12/2021] [Accepted: 02/26/2021] [Indexed: 01/05/2023] Open
Abstract
Background The mental health consequences of school closure, social isolation, increased financial and emotional stress, and greater exposure to family conflicts are likely to be pronounced for primary school children who are known to be vulnerable. Data from prior to the pandemic are needed to provide robust assessments of the impact of COVID‐19 on vulnerable children. Method The present study capitalises on an ongoing study of primary school children (4–8 years) identified as ‘at‐risk’ for mental health problems by teachers. We collected mental health and socio‐economic data prior to the pandemic and re‐assessed this cohort (n = 142) via researcher‐led video calls during the pandemic to evaluate the social and emotional impacts of COVID‐19 for these families. Results Mental health problems, particularly anxiety, increased significantly in these children. Parental mental health difficulties (anxiety and depression) were also prevalent. There were higher reports of financial stress during lockdown amongst low‐income families previously identified as living in poverty, prior to the COVID‐19 pandemic. Financial strain was found to indirectly predict increases in child mental health problems through parental mental health. Conclusion These findings show that the pandemic exacerbated mental health problems in already vulnerable children. These negative outcomes were explained by financial stress (e.g., lost employment, loss of income and inability to pay bills), which was negatively linked to parental mental health.
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Affiliation(s)
- Dolapo Adegboye
- Department of Psychology Cardiff University Cardiff South Glamorgan UK
| | - Ffion Williams
- Department of Psychology Cardiff University Cardiff South Glamorgan UK
| | - Stephan Collishaw
- Department of Psychological Medicine and Neurology Cardiff University School of Medicine Cardiff South Glamorgan Wales
| | - Katherine Shelton
- Department of Psychology Cardiff University Cardiff South Glamorgan UK
| | - Kate Langley
- Department of Psychology Cardiff University Cardiff South Glamorgan UK
| | | | - Daniel Burley
- Department of Psychology Cardiff University Cardiff South Glamorgan UK
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9
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Von Tokarski F, Hobson C, Lartigue MF, Lemaignen A, Lioger B. Streptococcus pyogenes necrotizing soft tissue infection following glucose monitoring with FreeStyle Libre device. QJM 2021; 114:58-59. [PMID: 32277817 DOI: 10.1093/qjmed/hcaa123] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- F Von Tokarski
- Department of Infectious Diseases and Internal Medicine, University Hospital of Tours, Francois Rabelais University, Tours, France
| | - C Hobson
- Department of Infectious Diseases and Internal Medicine, University Hospital of Tours, Francois Rabelais University, Tours, France
| | - M-F Lartigue
- Service de Bactériologie Virologie et Hygiène Hospitalière, University Hospital of Tours, Francois Rabelais University, Tours, France
| | - A Lemaignen
- Department of Infectious Diseases and Internal Medicine, University Hospital of Tours, Francois Rabelais University, Tours, France
| | - B Lioger
- Department of Internal Medicine, Hospital of Blois, Mail Pierre Charlot, Blois 41000, France
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Hobson C, Maakaroun Z, Dieckmann K, Bernard L, Amsellem-Jager J, Lemaignen A. A preliminary prospective study: Could the labeling of a health-care message on a consumer product limit forgetfulness in parents confronted with immunization? Arch Pediatr 2018; 26:65-70. [PMID: 30573376 DOI: 10.1016/j.arcped.2018.11.003] [Citation(s) in RCA: 1] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 08/30/2018] [Accepted: 11/10/2018] [Indexed: 11/25/2022]
Abstract
BACKGROUND Parental hesitancy in immunization is an emerging and concerning problem owing to the serious consequences of a lack of vaccination. Few tools are available to combat this phenomenon. AIMS To evaluate the interest of parents in recording the vaccine schedule on a common consumer product as a solution to prevent immunization oversight. METHOD We conducted a preliminary prospective and monocentric study, in a parental population, using surveys to evaluate interest in this solution, and to define the sociodemographic characteristics of our population. Our population was clustered into three groups: against immunization, hesitant/negligent, and pro-immunization. This solution was evaluated using a univariate model between fearful and confident populations in respect of immunization, associated with a descriptive analysis of the population against immunization. RESULTS Of 825 surveys distributed, 709 were analyzed. There were 47 parents against immunization (6.6%), 284 hesitant/negligent parents (40%), and 378 pro-immunization parents (53.3%). We showed that the hesitant/negligent population reported more difficulties in remembering the immunization schedule (P<0.001; OR=0.36; 95% CI [0.25-0.51]), and was interested in discussions on immunization (P<0.001; OR=0.41; 95% CI [0.29-0.58]). This population prone to oversight was interested in the labeling of an everyday consumer product with the immunization schedule (P=0.03; OR=0.68; 95% CI [1.02-2.11]) to limit the number of missed injections. CONCLUSION There is no single or perfect solution to combat the current anti-immunization problem, although communication through everyday consumer products seems to be an interesting tool for raising parental awareness of the importance of immunization. Further studies are required to evaluate the effectiveness of this tool.
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Affiliation(s)
- C Hobson
- Infectious disease department, hôpital Bretonneau, university hospital of Tours, 2, boulevard Tonnellé, 37044 cedex 9 Tours, France; General pediatrics department, hôpital Saint Gatien de Clocheville, university hospital of Tours, 59, boulevard Béranger, 37000 Tours, France.
| | - Z Maakaroun
- Infectious disease department, hôpital Bretonneau, university hospital of Tours, 2, boulevard Tonnellé, 37044 cedex 9 Tours, France; General pediatrics department, hôpital Saint Gatien de Clocheville, university hospital of Tours, 59, boulevard Béranger, 37000 Tours, France
| | - K Dieckmann
- General pediatrics department, Blois Hospital Center, Mail Pierre Charcot, 41000 Blois, France
| | - L Bernard
- Infectious disease department, hôpital Bretonneau, university hospital of Tours, 2, boulevard Tonnellé, 37044 cedex 9 Tours, France
| | - J Amsellem-Jager
- General pediatrics department, Blois Hospital Center, Mail Pierre Charcot, 41000 Blois, France
| | - A Lemaignen
- Infectious disease department, hôpital Bretonneau, university hospital of Tours, 2, boulevard Tonnellé, 37044 cedex 9 Tours, France
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Hobson C, Le Brun C, Beauruelle C, Maakaroun-Vermesse Z, Mereghetti L, Goudeau A, Lanotte P. Detection of Bartonella in cat scratch disease using a single-step PCR assay kit. J Med Microbiol 2017; 66:1596-1601. [PMID: 29068281 DOI: 10.1099/jmm.0.000626] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [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: 11/18/2022] Open
Abstract
PURPOSE Bartonella is an increasingly isolated emerging pathogen that can cause severe illness in humans, including cat scratch disease (CSD). The bacteria are difficult to grow and thus many detection methods have been developed, especially molecular. We previously developed a PCR method targeting ribC to identify Bartonella sp. A manufactured kit (RealCycler BART, Progenie Molecular) was commercialised shortly thereafter for the detection of Bartonella infection, including Bartonella henselae. METHODOLOGY We performed a comparison between this test and our in-house PCR assay on 73 lymphadenopathy samples sent to the laboratory for suspicion of CSD.Results/Key findings. Among the 28 positive samples for Bartonella, 21 were identified by the two PCR assays, and seven by the commercial kit only. CONCLUSION The performance of this commercial kit suggests that it could be a suitable alternative to our in-house PCR assay, highlighting the importance of the molecular methods used to diagnose CSD.
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Affiliation(s)
- C Hobson
- CHRU de Tours, Service de Bactériologie-Virologie, F-37044 Tours, France
| | - C Le Brun
- CHRU de Tours, Service de Bactériologie-Virologie, F-37044 Tours, France
| | - C Beauruelle
- CHRU de Tours, Service de Bactériologie-Virologie, F-37044 Tours, France.,ISP, INRA, Université François Rabelais de Tours, UMR 1282, F-37380, Nouzilly, France
| | - Z Maakaroun-Vermesse
- CHRU de Tours, Service de Médecine et Maladies Infectieuses, F-37044 Tours, France
| | - L Mereghetti
- CHRU de Tours, Service de Bactériologie-Virologie, F-37044 Tours, France.,ISP, INRA, Université François Rabelais de Tours, UMR 1282, F-37380, Nouzilly, France
| | - A Goudeau
- CHRU de Tours, Service de Bactériologie-Virologie, F-37044 Tours, France
| | - P Lanotte
- ISP, INRA, Université François Rabelais de Tours, UMR 1282, F-37380, Nouzilly, France.,CHRU de Tours, Service de Bactériologie-Virologie, F-37044 Tours, France
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Hobson C, Parris D. The Commodity-Proof Radiologist. J Am Coll Radiol 2017; 14:825-829. [DOI: 10.1016/j.jacr.2016.11.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Revised: 10/28/2016] [Accepted: 11/01/2016] [Indexed: 11/17/2022]
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Hobson C, Dubillot D, Lardy H, Sirinelli D, Saliba E, Lopez E. A Rare Complication of Central Venous Catheter Extravasation in a Preterm Neonate: Hemidiaphragmatic Paralysis. AJP Rep 2017; 7:e65-e67. [PMID: 28405492 PMCID: PMC5388554 DOI: 10.1055/s-0037-1601566] [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] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Abstract
We report a case of a preterm neonate born at 26 weeks' of gestation diagnosed with unilateral diaphragmatic paralysis. This paralysis was a consequence of a phrenic nerve injury due to extravasation of hyperosmolar parenteral nutrition fluid in the upper thorax. Chest X-rays and ultrasonography confirmed the diagnosis. The neonate was treated with prolonged respiratory support and did not require surgical treatment. This report describes a case of hemidiaphragmatic paralysis as a complication of central venous catheter insertion. In neonates, spontaneous recovery of diaphragmatic paralysis is possible. This study concludes that recovery of extravasation injury-induced phrenic nerve palsy in the context of conservative management is possible.
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Affiliation(s)
- C Hobson
- University François Rabelais, Faculty of Medecine, Tours, France; Neonatal and Pediatric Intensive Care Unit, Hôpital Clocheville, Tours, France
| | - D Dubillot
- University François Rabelais, Faculty of Medecine, Tours, France; Neonatal and Pediatric Intensive Care Unit, Hôpital Clocheville, Tours, France
| | - H Lardy
- University François Rabelais, Faculty of Medecine, Tours, France; Pediatric Surgery Department, Hôpital Clocheville, Tours, France
| | - D Sirinelli
- University François Rabelais, Faculty of Medecine, Tours, France; Pediatric Radiology Department, Hôpital Clocheville, Tours, France
| | - E Saliba
- University François Rabelais, Faculty of Medecine, Tours, France; Neonatal and Pediatric Intensive Care Unit, Hôpital Clocheville, Tours, France
| | - E Lopez
- Neonatal and Pediatric Intensive Care Unit, Hôpital Clocheville, Tours, France
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Hobson C, Henrot A, Dubillot D, Saliba E. P-097 – Un candidat au chylothorax congénital… le Candida parapsilosis. Arch Pediatr 2015. [DOI: 10.1016/s0929-693x(15)30282-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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D'Amore A, Amoroso N, Gottardi R, Hobson C, Carruthers C, Watkins S, Wagner WR, Sacks MS. From single fiber to macro-level mechanics: A structural finite-element model for elastomeric fibrous biomaterials. J Mech Behav Biomed Mater 2014; 39:146-61. [PMID: 25128869 PMCID: PMC4165725 DOI: 10.1016/j.jmbbm.2014.07.016] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Revised: 07/07/2014] [Accepted: 07/15/2014] [Indexed: 11/20/2022]
Abstract
In the present work, we demonstrate that the mesoscopic in-plane mechanical behavior of membrane elastomeric scaffolds can be simulated by replication of actual quantified fibrous geometries. Elastomeric electrospun polyurethane (ES-PEUU) scaffolds, with and without particulate inclusions, were utilized. Simulations were developed from experimentally-derived fiber network geometries, based on a range of scaffold isotropic and anisotropic behaviors. These were chosen to evaluate the effects on macro-mechanics based on measurable geometric parameters such as fiber intersections, connectivity, orientation, and diameter. Simulations were conducted with only the fiber material model parameters adjusted to match the macro-level mechanical test data. Fiber model validation was performed at the microscopic level by individual fiber mechanical tests using AFM. Results demonstrated very good agreement to the experimental data, and revealed the formation of extended preferential fiber orientations spanning the entire model space. We speculate that these emergent structures may be responsible for the tissue-like macroscale behaviors observed in electrospun scaffolds. To conclude, the modeling approach has implications for (1) gaining insight on the intricate relationship between fabrication variables, structure, and mechanics to manufacture more functional devices/materials, (2) elucidating the effects of cell or particulate inclusions on global construct mechanics, and (3) fabricating better performing tissue surrogates that could recapitulate native tissue mechanics.
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Affiliation(s)
- Antonio D'Amore
- McGowan Institute for Regenerative Medicine, Department of Bioengineering and Surgery, University of Pittsburgh, USA; Fondazione RiMED, Italy; DICGIM, University of Palermo, Italy
| | - Nicholas Amoroso
- McGowan Institute for Regenerative Medicine, Department of Bioengineering and Surgery, University of Pittsburgh, USA
| | - Riccardo Gottardi
- McGowan Institute for Regenerative Medicine, Department of Bioengineering and Surgery, University of Pittsburgh, USA; Fondazione RiMED, Italy
| | - Christopher Hobson
- McGowan Institute for Regenerative Medicine, Department of Bioengineering and Surgery, University of Pittsburgh, USA
| | - Christopher Carruthers
- McGowan Institute for Regenerative Medicine, Department of Bioengineering and Surgery, University of Pittsburgh, USA
| | - Simon Watkins
- McGowan Institute for Regenerative Medicine, Department of Bioengineering and Surgery, University of Pittsburgh, USA
| | - William R Wagner
- McGowan Institute for Regenerative Medicine, Department of Bioengineering and Surgery, University of Pittsburgh, USA
| | - Michael S Sacks
- Center for Cardiovascular Simulation, Institute for Computational and Engineering Sciences, Department of Biomedical Engineering, University of Texas at Austin, TX 78712, USA.
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16
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Sankar MS, Vega MA, Defoe PP, Kibria MG, Ford S, Telfeyan K, Neal A, Mohajerin TJ, Hettiarachchi GM, Barua S, Hobson C, Johannesson K, Datta S. Elevated arsenic and manganese in groundwaters of Murshidabad, West Bengal, India. Sci Total Environ 2014; 488-489:570-9. [PMID: 24694939 DOI: 10.1016/j.scitotenv.2014.02.077] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2013] [Revised: 02/14/2014] [Accepted: 02/14/2014] [Indexed: 05/02/2023]
Abstract
High levels of geogenic arsenic (As) and manganese (Mn) in drinking water has led to widespread health problems for the population of West Bengal, India. Here we delineate the extent of occurrences of As and Mn in Murshidabad, where the contaminated aquifers occur at shallow depths between 35 and 40 m and where access to safe drinking water is a critical issue for the local population. A total of 78 well-water samples were taken in 4 blocks on either side of the river Bhagirathi: Nabagram and Kandi (west, Pleistocene sediments), Hariharpara and Beldanga (east, Holocene sediments). High As, total iron (FeT) and low Mn concentrations were found in waters from the Holocene gray sediment aquifers east of the river Bhagirathi, while the opposite was found in the Pleistocene reddish-brown aquifer west of the river Bhagirathi in Murshidabad. Speciation of As in water samples from Holocene sediments revealed the dominant species to be As(III), with ratios of As(III):AsT ranging from 0.55 to 0.98 (average 0.74). There were indications from saturation index estimations that Mn solubility is limited by the precipitation of MnCO3. Tubewells from high As areas in proximity to anthropogenic waste influx sources showing high molar Cl/Br ratios, low SO4(2-) and low NO3(-) demonstrate relatively lower As concentrations, thereby reducing As pollution in those wells. Analyses of core samples (2 in each of the blocks) drilled to a depth of 45 m indicate that there is no significant variation in bulk As (5-20mg/kg) between the Holocene and Pleistocene sediments, indicating that favorable subsurface redox conditions conducive to mobilization are responsible for the release of As. The same applies to Mn, but concentrations vary more widely (20-2000 mg/kg). Sequential extraction of Holocene sediments showed As to be associated with 'specifically sorbed-phosphate-extractable' phases (10-15%) and with 'amorphous and well crystalline Fe-oxyhydroxide' phases (around 37%) at As-contaminated well depths, suggesting that the main As release mechanisms could be either competitive ion exchange with PO4(3-), or the dissolution of Fe oxyhydroxides. In the Pleistocene sediments Mn is predominantly found in the easily exchangeable fraction.
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Affiliation(s)
- M S Sankar
- Department of Geology, Kansas State University, Manhattan, KS 66506, USA
| | - M A Vega
- Department of Geology, Kansas State University, Manhattan, KS 66506, USA
| | - P P Defoe
- Department of Agronomy, Kansas State University, Manhattan, KS 66506, USA
| | - M G Kibria
- Department of Geology, Kansas State University, Manhattan, KS 66506, USA
| | - S Ford
- Department of Geology, Kansas State University, Manhattan, KS 66506, USA
| | - K Telfeyan
- Department of Earth and Environmental Sciences, Tulane University, New Orleans 70118, USA
| | - A Neal
- Virginia Water Resources Research Center, Virginia Tech, VA 24061, USA
| | - T J Mohajerin
- Department of Earth and Environmental Sciences, Tulane University, New Orleans 70118, USA
| | - G M Hettiarachchi
- Department of Agronomy, Kansas State University, Manhattan, KS 66506, USA
| | - S Barua
- Department of Geology, Kansas State University, Manhattan, KS 66506, USA
| | - C Hobson
- Department of Geology, Kansas State University, Manhattan, KS 66506, USA
| | - K Johannesson
- Department of Earth and Environmental Sciences, Tulane University, New Orleans 70118, USA
| | - S Datta
- Department of Geology, Kansas State University, Manhattan, KS 66506, USA.
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Abramson S, Ackermann DM, Akins R, Anders R, Andersen PJ, Anderson JM, Ankrum JA, Anseth KS, Antonucci J, Atzet S, Badylak SF, Baura GD, Bellamkonda RV, Best SM, Bhumiratana S, Bianco RW, Bokros JC, Borovetz HS, Boskey AL, Brown JL, Brown BN, Brown SA, Brunski JB, Cahn F, Ritchie AC, Caplan AI, Carpenedo RL, Chilkoti A, Chung S, Cimetta E, Cleary G, Clements IP, Colas A, Coleman KP, Conway DE, Cooper SL, Costerton B, Coury AJ, Cunanan C, Curtis J, D’Amore A, DeMeo P, Desai TA, Dickens S, Domingo G, Duncan E, Eskin SG, Feigal DW, Ferreira L, Fuller J, Gallegos RP, Gawalt E, Ghosh K, Ghosn B, Gilbert TW, Glaser DE, Godier-Furnemont A, Gombotz WR, Grainger DW, Grunkemeier GL, Hacking SA, Hallab NJ, Hall-Stoodley L, Hanson SR, Haubold AD, Hauch KD, Hawkins KR, Heath DE, Helm DL, Hench LL, Hensten A, Hill RT, Hobson C, Hoerstrup SP, Hoffman AS, Horbett TA, Hubbell JA, Humayun MS, Ideker R, Ingber DE, Jain R, Jacob J, Jacobs JJ, Jacobsen N, Jin R, Johnson RJ, Karp JM, Kasper FK, Kathju S, Khademhosseini A, Kim S, King MW, Kleiner LW, Kohn J, Koschwanez HE, Kumbar SG, Kuo CK, LaFleur L, Lahti MT, Lambert B, Langer R, Laurencin CT, Lee-Parritz D, Lemons JE, Levin M, Levy RJ, Lewerenz GM, Li WJ, Lin CC, Liu F, Lowrie WG, Lu Y, Lysaght MJ, Maidhof R, Mansbridge J, Cristina M, Martins L, Martin J, Mayesh JP, McDevitt TC, McIntire LV, Merrit K, Migliaresi C, Mikos AG, Misch CE, Mitchell RN, More RB, Moss CW, Munson JM, Navarro M, Nerem RM, Ogawa R, Orgill BD, Orgill DP, Padera RF, Pandit A, Park K, Patel AS, Peck RB, Peckham PH, Peppas NA, Pereira MN, Planell J, Popat KC, Prestwich GD, Pun SH, Rabolt J, Rainbow RS, Rajab T, Ratner BD, Reichert WM, Rivard AL, Rowley AP, Ruan G, Sacks M, Sarkar D, Schaefer S, Schmidt CE, Schoen FJ, Schutte SC, Sefton MV, Shalaby SW, Shirtliff M, Simon MA, Singh M, Slack SM, Spelman FA, Starr A, Stayton PS, Steinert R, Stoodley P, Suri S, Swi Chang TM, Tandon N, Tanguay AR, Taylor MS, Teo GS, Thodeti CK, Tolkoff J, Treiser M, Tuan RS, Tucker EI, Venugopalan R, Vicari AR, Viney C, Voight JM, Vunjak-Novakovic G, Wagner WR, Wang L, Wasiluk KR, Watts DC, Weigl BH, Weiland JD, Whalen JJ, Williams DF, Williams RL, Wilson JT, Wilson CG, Winter J, Wolf MF, Wright JC, Yager P, Zhao W. Contributors. Biomater Sci 2013. [DOI: 10.1016/b978-0-08-087780-8.00150-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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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18
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Perks TD, Trauernicht C, Hartley T, Hobson C, Lawson A, Scholtz P, Dendere R, Steiner S, Douglas TS. Effect of aluminium filtration on dose and image quality in paediatric slot-scanning radiography. Annu Int Conf IEEE Eng Med Biol Soc 2013; 2013:2332-2335. [PMID: 24110192 DOI: 10.1109/embc.2013.6610005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
This paper examines the effect that a 1.8 mm aluminium filter has on paediatric patient dose and image quality for linear slot scanning radiography (LSSR). A dynamic dose prediction model for LSSR accurately predicted the dose reduction effects of added aluminium filtration. A cadaver imaging study was carried out to assess the effects of filtration on image quality. With 1.8 mm added aluminium filtration, no visible degradation to image contrast or clarity was found, and in some cases the aluminium filtration improved the image quality as judged by radiologists.
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19
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Fan R, Hobson C, Bayoumi A, Mayer J, Wagner W, Sacks MS. A Design Framework of Unloaded Leaflet Shape for the Ovine Pulmonary Valve Single Leaflet Replacement Surgery. J Med Device 2011. [DOI: 10.1115/1.3591385] [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: 11/08/2022] Open
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20
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Mochalin VN, Osswald S, Portet C, Yushin G, Hobson C, Havel M, Gogotsi Y. High Temperature Functionalization and Surface Modification of Nanodiamond Powders. ACTA ACUST UNITED AC 2011. [DOI: 10.1557/proc-1039-p11-03] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
AbstractHigh temperature annealing in vacuum, air, hydrogen, chlorine, and ammonia are described as a means to change surface chemistry and phase composition of nanodiamond powders of three different grades, which have different sp2/sp3 carbon ratios. The changes in surface chemistry and phase composition of the powders are analyzed using Raman spectroscopy and Fourier Transform Infra Red (FTIR) spectroscopy. Advantages and limitation of high-temperature treatment techniques as well as potential applications of the gas-treated nanodiamond powders are discussed.
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21
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Davey G, Allen N, Appleby P, Spencer E, Verkasalo P, Knox K, Postans J, Tipper S, Hobson C, Key T. Dietary and lifestyle characteristics of meat-eaters, fish-eaters, vegetarians and vegans. IARC Sci Publ 2003; 156:113-4. [PMID: 12484139] [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: 02/28/2023]
Affiliation(s)
- G Davey
- Imperial Cancer Research Fund, Cancer Epidemiology Unit, University of Oxford, Oxford, OX2 6HE, UK
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Abstract
This article addresses one of the perennial problems of pilot selection research: obtaining an adequate sample size for reliable statistical analysis of predictive validity. Results from three studies involving the same computerized tests of instrument comprehension and psychomotor ability were combined in a meta-analysis to determine whether the validities of these tests generalized across three contexts. These were Royal Air Force and Turkish Air Force fixed-wing pilot training and British Army Air Corps rotary-wing pilot training. In this article, we discuss the adequacy of samples for estimating the validity of the tests, and the persistence of predictive validity to later stages of training as shown by British Army Air Corps data. Reference is also made to data from a fourth independent study of Qantas pilot training.
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23
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Freitag S, Hobson C, Biggs HC, Jaarsveld AS. Testing for potential survey bias: the effect of roads, urban areas and nature reserves on a southern African mammal data set. Anim Conserv 1998. [DOI: 10.1111/j.1469-1795.1998.tb00019.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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24
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Brennan RJ, Hobson C, Bolton P, Hinkle T, Chermel K, Aplenc R. Medical relief in central Bosnia. Med J Aust 1994; 161:675-9. [PMID: 7830635] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- R J Brennan
- International Medical Corps, Zenica Regional Hospital, Bosnia-Hercegovina
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Abstract
Madin-Darby canine kidney (MDCK) cells are unable to form desmosomes when cultured in low-calcium medium [( Ca2+] less than 0.1 meq./l), but can be induced to do so by raising the calcium to physiological concentrations (1-2 meq./l). We have previously demonstrated that this block correlated with increased desmosomal protein turnover. Here we have immunoprecipitated the major desmosome glycoproteins [DGI (150 kDa) and DGII/III (120/100 kDa)] from non-ionic detergent-soluble and -insoluble fractions prepared from metabolically labelled MDCK cells cultured in standard or low-calcium medium. Pulse-chase studies showed that both DGI and DGII/III became unextractable in non-ionic detergent before their arrival at the cell surface, whether cells were grown in standard or low-calcium medium. The non-ionic detergent insolubility of these membrane components is therefore a separate step which precedes the formation of morphologically recognisable desmosomes.
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Affiliation(s)
- E J Penn
- National Institute for Medical Research, London, England
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Penn EJ, Burdett ID, Hobson C, Magee AI, Rees DA. Structure and assembly of desmosome junctions: biosynthesis and turnover of the major desmosome components of Madin-Darby canine kidney cells in low calcium medium. J Biophys Biochem Cytol 1987; 105:2327-34. [PMID: 3680384 PMCID: PMC2114848 DOI: 10.1083/jcb.105.5.2327] [Citation(s) in RCA: 66] [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] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Neither stratifying (primary keratinocytes) nor simple (Madin-Darby canine kidney [MDCK] and Madin-Darby bovine kidney [MDBK]) epithelial cell types from desmosomes in low calcium medium (LCM; less than 0.1 mM), but they can be induced to do so by raising the calcium level to physiological concentrations (standard calcium medium [SCM], 2 mM). We have used polyclonal antisera to the major bovine epidermal desmosome components (greater than 100 kD) in a sensitive assay involving immunoprecipitation of the components from metabolically labeled MDCK cell monolayers to investigate the mechanism of calcium-induced desmosome formation. MDCK cells, whether cultured in LCM or SCM, were found to synthesize the desmosome protein, DPI and desmosome glycoproteins DGI and DGII/III with identical electrophoretic mobility, and also, where relevant, with similar carbohydrate addition/processing and proteolytic processing. The timings of these events and of transport of DGI to the cell surface were similar in low and high calcium. Although the rates of synthesis of the various desmosome components were also similar under both conditions, the glycoprotein turnover rates increased dramatically in cells cultured in LCM. The half-lives decreased by a factor of about 7 for DGI and 12 for DGII/III and, consistent with this, MDCK cells labeled for 48 h in SCM had three and six times the amount of DGI and DGII/III, respectively, as cells labeled for 48 h in LCM. The rate of turnover and the levels of DPI were changed in the same direction, but to much lesser extents. Possible mechanisms for the Ca2+-dependent control of desmosome formation are discussed in the light of this new evidence.
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Affiliation(s)
- E J Penn
- National Institute for Medical Research, London, United Kingdom
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Penn EJ, Hobson C, Rees DA, Magee AI. Structure and assembly of desmosome junctions: biosynthesis, processing, and transport of the major protein and glycoprotein components in cultured epithelial cells. J Biophys Biochem Cytol 1987; 105:57-68. [PMID: 3611196 PMCID: PMC2114930 DOI: 10.1083/jcb.105.1.57] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Extracts of metabolically labeled cultured epithelial cells have been analyzed by immunoprecipitation followed by SDS-PAGE, using antisera to the major high molecular mass proteins and glycoproteins (greater than 100 kD) from desmosomes of bovine muzzle epidermis. For nonstratifying cells (Madin-Darby canine kidney [MDCK] and Madin-Darby bovine kidney), and A431 cells that have lost the ability to stratify through transformation, and a stratifying cell type (primary human keratinocytes) apparently similar polypeptides were immunoprecipitated with our antisera. These comprised three glycoproteins (DGI, DGII, and DGIII) and one major nonglycosylated protein (DPI). DPII, which has already been characterized by others in stratifying tissues, appeared to be absent or present in greatly reduced amounts in the nonstratifying cell types. The desmosome glycoproteins were further characterized in MDCK cells. Pulse-chase studies showed all three DGs were separate translation products. The two major glycoprotein families (DGI and DGII/III) were both found to be synthesized with co-translational addition of 2-4 high mannose cores later processed into complex type chains. However, they became endo-beta-N-acetylglucosaminidase H resistant at different times (DGII/III being slower). None of the DGs were found to have O-linked oligosaccharides unlike bovine muzzle DGI. Transport to the cell surface was rapid for all glycoproteins (60-120 min) as demonstrated by the rate at which they became sensitive to trypsin in intact cells. This also indicated that they were exposed at the outer cell surface. DGII/III, but not DGI, underwent a proteolytic processing step, losing 10 kD of carbohydrate-free peptide, during transport to the cell surface suggesting a possible regulatory mechanism in desmosome assembly.
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