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Selden C, Erro E, Brookshaw T, Zotova E, da Silva JM, Farid S, Opie J, Fuller B. Tissue Engineering: Late Breaking Abstract: HEPATICAN™: A COMBINED CELL THERAPY AND MEDICAL DEVICE TO TREAT PATIENTS WITH LIVER FAILURE. Cytotherapy 2022. [DOI: 10.1016/s1465-3249(22)00121-9] [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: 11/29/2022]
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Sutton E, Killian N, Perry B, Stas J, Opie J, Toepritz A, Ransley B, Toms J, Steele P. Coventry University telehealth coaching – A pilot. Physiotherapy 2022. [DOI: 10.1016/j.physio.2021.12.086] [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: 11/24/2022]
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Phillips L, Opie J. The utility of bone marrow sampling in the diagnosis and staging of lymphoma in South Africa. Int J Lab Hematol 2018; 40:276-283. [PMID: 29427399 DOI: 10.1111/ijlh.12782] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [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: 10/05/2017] [Accepted: 12/19/2017] [Indexed: 02/01/2023]
Abstract
INTRODUCTION The bone marrow biopsy (BMB) is a diagnostic and staging tool in lymphoma that remains practically useful and relevant in resource-constrained settings, despite restricted applications in international staging guidelines, which favour less invasive nuclear medicine techniques. METHODS Retrospective laboratory data review of BMBs in adult lymphoma patients from 2005 to 2010 to determine subtypes, rates of bone marrow involvement (BMI), human immunodeficiency virus (HIV) seroprevalence and CD4 counts, trephine length and additional findings. RESULTS A total of 1215 BMBs reported in lymphoma included 759 newly diagnosed patients, with BMI in 43.6% of non-Hodgkin lymphoma (NHL) overall, 28.9% of high-grade B subtypes and 35.7% of Hodgkin lymphoma (HL). HIV seroprevalence was 38.8%, 53.0% and 33.9% in the 3 respective groups. There was a statistical association between BMI and HIV seropositivity in Burkitt lymphoma and HL, and BMI and CD4 count in HIV-related HL. Over 10% (n = 79) of new lymphoma cases were diagnosed by BMB with ancillary tests. Occasional histological discordance and transformation were reported in NHL. Focal/unilateral BMI was uncommon. Bilateral BMB and biopsy length exceeding 26 mm did not improve BMI detection. CONCLUSION In the South African public sector, high HIV prevalence leads to a different lymphoma pathology profile from the developed world. High BMI rates are encountered. Here, and in similar resource-constrained settings, international lymphoma staging guidelines can be logistically challenging and unaffordable. BMB remains useful in the staging and diagnosis of lymphoma. Unilateral sampling with a processed trephine length of at least 26 mm is recommended.
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Affiliation(s)
- L Phillips
- Department of Haematology, Red Cross War Memorial Children's Hospital Laboratory, National Health Laboratory Service, Cape Town, South Africa.,Division of Haematology, Department of Pathology, University of Cape Town, Cape Town, South Africa
| | - J Opie
- Division of Haematology, Department of Pathology, University of Cape Town, Cape Town, South Africa.,Department of Haematology, Groote Schuur Hospital Laboratory, National Health Laboratory Service, Cape Town, South Africa
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Guzha B, Adams T, Rogers L, Mbatani N, Wu HT, Fakie N, Opie J, Denny L. Endometrial cancer with bone marrow metastases: a management dilemma. Southern African Journal of Gynaecological Oncology 2017. [DOI: 10.1080/20742835.2017.1394628] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Affiliation(s)
- Bt Guzha
- Division of Gynaecology Oncology, Department of Obstetrics and Gynaecology, Groote Schuur Hospital, Cape Town, South Africa
- South African Medical Research Council (SAMRC)/University of Cape Town (UCT) Gynaecological Cancer Research Centre, Cape Town, South Africa
| | - T Adams
- Division of Gynaecology Oncology, Department of Obstetrics and Gynaecology, Groote Schuur Hospital, Cape Town, South Africa
- South African Medical Research Council (SAMRC)/University of Cape Town (UCT) Gynaecological Cancer Research Centre, Cape Town, South Africa
| | - L Rogers
- Division of Gynaecology Oncology, Department of Obstetrics and Gynaecology, Groote Schuur Hospital, Cape Town, South Africa
- South African Medical Research Council (SAMRC)/University of Cape Town (UCT) Gynaecological Cancer Research Centre, Cape Town, South Africa
| | - N Mbatani
- Division of Gynaecology Oncology, Department of Obstetrics and Gynaecology, Groote Schuur Hospital, Cape Town, South Africa
- South African Medical Research Council (SAMRC)/University of Cape Town (UCT) Gynaecological Cancer Research Centre, Cape Town, South Africa
| | - H-t Wu
- South African Medical Research Council (SAMRC)/University of Cape Town (UCT) Gynaecological Cancer Research Centre, Cape Town, South Africa
- Division of Anatomical Pathology, Groote Schuur Hospital and the National Health Laboratory Service, Cape Town, South Africa
| | - N Fakie
- South African Medical Research Council (SAMRC)/University of Cape Town (UCT) Gynaecological Cancer Research Centre, Cape Town, South Africa
- Department of Radiation Oncology, Groote Schuur Hospital, Cape Town, South Africa
| | - J Opie
- Division of Haematology Pathology, Groote Schuur Hospital, National Health Laboratory Service and UCT, Cape Town, South Africa
| | - La Denny
- Division of Gynaecology Oncology, Department of Obstetrics and Gynaecology, Groote Schuur Hospital, Cape Town, South Africa
- South African Medical Research Council (SAMRC)/University of Cape Town (UCT) Gynaecological Cancer Research Centre, Cape Town, South Africa
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Kerkhoff AD, Meintjes G, Opie J, Vogt M, Jhilmeet N, Wood R, Lawn SD. Anaemia in patients with HIV-associated TB: relative contributions of anaemia of chronic disease and iron deficiency. Int J Tuberc Lung Dis 2017; 20:193-201. [PMID: 26792471 PMCID: PMC6371921 DOI: 10.5588/ijtld.15.0558] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND: Anaemia commonly complicates both human immunodeficiency virus (HIV) infection and tuberculosis (TB), contributing substantially to morbidity and mortality. The mechanisms underlying anaemia and corresponding treatments in co-infected patients are poorly defined. OBJECTIVE: To determine the relative contributions of anaemia of chronic disease (ACD) and iron deficiency to anaemia in patients with HIV-associated TB. DESIGN: Consecutively recruited hospitalised (n = 102) and matched ambulatory patients (n = 51) with microbiologically confirmed HIV-associated TB in Cape Town, South Africa, were included. Haemoglobin levels, iron status markers, hepcidin and pro-inflammatory cytokines in blood were measured. We determined the prevalence of ACD and iron-deficiency anaemia (IDA) using seven different published definitions of IDA. RESULTS: More than 80% of enrolled HIV-associated TB patients were anaemic, and anaemia was more severe among in-patients. Over 95% of anaemic HIV-associated TB patients had ACD, whereas the proportion with IDA using a range of seven different definitions was low overall (median < 3%, range 0–32.6) in both patient groups. The proportion with IDA and hepcidin concentration ⩽ 20.0 ng/ml (predictive of responsiveness to oral iron supplementation) was also very low (median < 3%, range 0–15.1). CONCLUSIONS: ACD was the predominant cause underlying anaemia in HIV-associated TB patients, and IDA was very uncommon in this setting. The majority of anaemic HIV-associated TB patients were unlikely to benefit from oral iron supplementation.
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Affiliation(s)
- A D Kerkhoff
- Department of Medicine, University of California San Francisco School of Medicine, San Francisco, California, USA; Department of Global Health, Academic Medical Center, Amsterdam Institute for Global Health and Development, University of Amsterdam, Amsterdam, The Netherlands; The Desmond Tutu HIV Centre, Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - G Meintjes
- Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa; Clinical Infectious Diseases Research Initiative, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa; Department of Medicine, Imperial College, London, UK
| | - J Opie
- Division of Haematology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa; C17 Clinical Pathology Laboratory, National Health Laboratory Service and Groote Schuur Hospital, Cape Town, South Africa
| | - M Vogt
- The Desmond Tutu HIV Centre, Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - N Jhilmeet
- Clinical Infectious Diseases Research Initiative, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - R Wood
- The Desmond Tutu HIV Centre, Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - S D Lawn
- The Desmond Tutu HIV Centre, Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa; Department of Clinical Research, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK
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Dalley-Hewer J, Opie J, Knowles N. A creative alternative to reflective writing: promoting skills of reflection through walking a labyrinth. Physiotherapy 2015. [DOI: 10.1016/j.physio.2015.03.3638] [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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Opie J, Parkes S. Empathy: can it be enhanced by learning from the interactions between healthcare professionals with a disability and their patients? Physiotherapy 2015. [DOI: 10.1016/j.physio.2015.03.2097] [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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Kavsak P, Worster A, Devereaux P, Heels-Ansdell D, Guyatt G, Opie J, Mookadam F, Hill S. A clinically sensitive cardiac troponin I assay (AccuTnI) versus the high sensitive cardiac troponin T assay to predict early serious cardiac outcomes in patients with potential acute coronary syndrome. Clin Biochem 2011. [DOI: 10.1016/j.clinbiochem.2011.06.038] [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: 11/29/2022]
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van Schalkwyk WA, Opie J, Novitzky N. The diagnostic utility of bone marrow biopsies performed for the investigation of fever and/or cytopenias in HIV-infected adults at Groote Schuur Hospital, Western Cape, South Africa. Int J Lab Hematol 2010; 33:258-66. [PMID: 21118385 DOI: 10.1111/j.1751-553x.2010.01280.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
INTRODUCTION A bone marrow biopsy is frequently requested in the work-up of patients with human immunodeficiency virus (HIV) infection who present with fever and/or cytopenias in the search for opportunistic infections and malignancies. METHODS This is a retrospective review of the results of consecutive bone marrow biopsies performed at our institution over a three-year period on HIV-positive patients for the investigation of fever and/or cytopenias. Clinical data, haematological parameters, morphological features, Ziehl-Neelsen staining and microbiological culture results were analysed. The aim of the study was to determine the diagnostic yield of this investigation. RESULTS Sixty-three males and 84 female patients were included for analysis. The bone marrow biopsy gave a high diagnostic yield of 47% (70 patients) and a unique diagnosis in 33% (49 patients). Immune thrombocytopenic purpura and disseminated mycobacterial infections were the most common unique diagnoses made (14%, respectively), followed by malignancies (4%). In this cohort, four cases of primary bone marrow involvement by Hodgkin lymphoma and one case of involvement by non-Hodgkin lymphoma were diagnosed. CONCLUSION In our study group, a bone marrow biopsy was a useful investigation with a high diagnostic yield.
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Affiliation(s)
- W A van Schalkwyk
- Department of Haematology, Groote Schuur Hospital and National Health Laboratory Service, University of Cape Town, Cape Town, South Africa.
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Baumgartner WD, Böheim K, Hagen R, Müller J, Lenarz T, Reiss S, Schlögel M, Mlynski R, Mojallal H, Colletti V, Opie J. The vibrant soundbridge for conductive and mixed hearing losses: European multicenter study results. Adv Otorhinolaryngol 2010; 69:38-50. [PMID: 20610913 DOI: 10.1159/000318521] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
BACKGROUND/AIMS The Vibrant Soundbridge (VSB) is an active middle ear implant, 'direct-drive' hearing system for the treatment of hearing loss. Recently, the VSB has been applied to conductive and mixed hearing losses. The aim of this study is to evaluate aided benefit, speech recognition in quiet and noise, subjective benefits, changes in residual hearing, and medical and surgical complications in adults with conductive or mixed hearing losses implanted with the VSB using Round Window (RW) Vibroplasty. METHODS Twelve German-speaking adults participated in a single-subject, repeated measures study design comparing their performance using the VSB with their own unaided preoperative performance. Hearing performance and changes in residual hearing were assessed using routine audiometric measures, sound field thresholds, and word and sentence recognition in quiet and in noise. Subjective benefits, including subjective hearing performance, device satisfaction, and quality of life were evaluated using the Abbreviated Profile of Hearing Aid Benefit, the Hearing Device Satisfaction Scale, and the Glasgow Benefit Inventory, respectively. RESULTS Aided hearing thresholds, word recognition at conversational levels, and sentence recognition in quiet and noise were significantly improved without significant changes in residual cochlear hearing and without major medical and surgical complications. One subject required repositioning surgery to improve transducer coupling with the RW membrane. Subjective benefit and device satisfaction were good, as were overall and general quality of life. CONCLUSION The VSB, implanted using RW vibroplasty, is a safe and effective treatment for adults with conductive and mixed hearing losses who may have few, if any, other options.
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Ritchie CW, Chiu E, Harrigan S, MacFarlane S, Mastwyk M, Halliday G, Hustig H, Hall K, Hassett A, O'Connor DW, Opie J, Nagalingam V, Snowdon J, Ames D. A comparison of the efficacy and safety of olanzapine and risperidone in the treatment of elderly patients with schizophrenia: an open study of six months duration. Int J Geriatr Psychiatry 2006; 21:171-9. [PMID: 16416458 DOI: 10.1002/gps.1446] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Following an earlier study in which elderly patients with schizophrenia had their typical antipsychotic medication changed to olanzapine or risperidone, the 61 patients were followed for up to a further six months to see if either treatment was superior in terms of efficacy or side effects. AIMS To determine whether either olanzapine or risperidone was superior in terms of efficacy or side effects when treating schizophrenia in late life. METHODS Psychiatric symptoms, side effects and quality of life were rated every six weeks for 24 weeks of open label comparative treatment using standard measures. Group differences were examined using analysis of covariance and within-group changes over time were assessed using paired t-tests. RESULTS There were 34 olanzapine and 32 risperidone patients who entered the study, but intention to treat data was only available for 61 of the 66 patients. There were no clinical or demographic differences between the groups. Parkinsonism, positive and negative symptoms of schizophrenia improved in both groups both from baseline switch to olanzapine or risperidone and during the six month follow-up after completion of crossover. No significant differences were seen between groups on most measures. However, patients treated with olanzapine showed a significantly greater improvement in quality of life from baseline compared to risperidone patients. CONCLUSIONS Both drugs were well tolerated and their use was associated with fewer symptoms of schizophrenia and less adverse effects than were seen when the patients were taking a typical antipsychotic at baseline. Olanzapine appears to have particular benefit with regard to quality of life.
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Affiliation(s)
- C W Ritchie
- Metabolic and Clinical Trials Unit, Department of Mental Health Sciences, Royal Free and University College Medical School, London, UK.
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Ritchie CW, Chiu E, Harrigan S, Hall K, Hassett A, Macfarlane S, Mastwyk M, O'Connor DW, Opie J, Ames D. The impact upon extra-pyramidal side effects, clinical symptoms and quality of life of a switch from conventional to atypical antipsychotics (risperidone or olanzapine) in elderly patients with schizophrenia. Int J Geriatr Psychiatry 2003; 18:432-40. [PMID: 12766921 DOI: 10.1002/gps.862] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Atypical antipsychotics are commonly used in the management of schizophrenia in late life with evidence suggesting they induce lower rates of motor disturbance, but have similar efficacy to conventional antipsychotics. Trials in the elderly have been either retrospective, small, of short duration or of a single-arm design. AIMS To demonstrate the effects upon motor side-effects, efficacy, safety and quality of life (QOL) of switching elderly patients with schizophrenia from conventional antipsychotics to olanzapine or risperidone. METHODS Elderly patients with schizophrenia were randomly allocated to olanzapine or risperidone and followed through an open-label crossover period. Between and within group intention to treat analyses were conducted. RESULTS 66 patients were randomised (mean age 69.6 [SD +/- 6.2]). Four (11.8%) patients on olanzapine and 8 (26.7%) patients on risperidone failed to complete the crossover because of treatment failure [Odds Ratio (OR) = 2.73[0.73-10.2] p = 0.14]. The mean doses upon completion of switching in each arm were 9.9 mg (SD = 4.2) and 1.7 mg (SD = 1.2) for olanzapine and risperidone respectively. In both arms there was improvement in Parkinsonism, though only olanzapine was associated with a reduction in dyskinetic symptoms. The Brief Psychiatric Rating Scale, Scale for the assessment of Negative Symptoms and Montgomery and Asberg Depression Rating Scale scores all improved through the crossover period in both arms with no between group differences. Treatment with olanzapine was associated with a better response over risperidone on the psychological domain of the World Health Organisation-Quality Of Life [Brief] (WHO-QOL-BREF) scale ( p = 0.02). Patients in the olanzapine arm also demonstrated improvement from baseline in the WHO-QOL-BREF physical, psychological and health satisfaction domains, but risperidone had no effect on any Quality of Life (QOL) measure. CONCLUSIONS After switching from a conventional antipsychotic, olanzapine and risperidone were associated with improvement in core symptoms of schizophrenia and motor side effects. Subjects switched to olanzapine were more likely to complete the switching process and show an improvement in psychological QOL.
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Affiliation(s)
- C W Ritchie
- Department of Psychiatry and Behavioural Sciences, Royal Free and University College Medical School, London, UK.
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Abstract
OBJECTIVE This paper provides a systematic review of research findings published between 1989 and 1998 concerning non-pharmacological strategies to alleviate behavioural disturbances in elderly persons with dementia. METHOD Data collection strategies included computer literature searches, manual searches of selected journals and checks of references listed in previous reviews. To warrant inclusion, studies were required to include some measure of behaviour before and after the introduction of an intervention. Papers were appraised in the following domains: design, sampling technique, setting, behaviours studied, measurement tools, data collection methods, type of interventions and feasibility. An overall validity rating was assigned to each article using predetermined rules. RESULTS Forty-three studies met criteria for inclusion including five randomised controlled trials. Validity ratings were as follows: one strong, 15 moderate, and 27 weak. Areas of scientific weakness included small numbers of subjects, inadequate descriptions of study participants, imprecise data collection methods, high attrition rates and insufficient statistical analysis. Despite this, there is evidence to support the efficacy of activity programs, music, behaviour therapy, light therapy, carer education and changes to the physical environment. The evidence in favour of multidisciplinary teams, massage and aromatherapy is inconclusive. CONCLUSIONS It was easier to interpret the results of rigorously designed studies that focused on a single behaviour or single intervention tailored to the needs of individuals and carers. Future studies should seek to replicate the findings outlined here, improving methodologies where necessary and including outcome measures that encompass the interests of people with dementia, family caregivers and health professionals.
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Affiliation(s)
- J Opie
- Aged Mental Health Research Group, Kingston Centre, Australia.
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Geier L, Barker M, Fisher L, Opie J. The effect of long-term deafness on speech recognition in postlingually deafened adult CLARION cochlear implant users. Ann Otol Rhinol Laryngol Suppl 1999; 177:80-3. [PMID: 10214807 DOI: 10.1177/00034894991080s416] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Research suggests that duration of deafness prior to cochlear implantation affects postoperative speech recognition in adults. Duration of deafness usually is defined as the number of years between the onset of profound deafness and implantation. The purpose of this study was to examine the effects of duration of deafness--expressed as percentage of life with deafness--independent of age at implantation on postoperative speech recognition in adult postlingually deafened CLARION Multi-Strategy Cochlear Implant users. Speech recognition tests (CID sentences and NU6 words) were administered to 202 consecutively implanted adults preoperatively and at 3 and 6 months after initial device fitting. Patients implanted at a younger age and those with smaller percentages of their lives with deafness achieved the highest levels of short-term postoperative speech recognition. Patients who had been deaf for > or =60% of their lives demonstrated a slower rate of speech recognition improvement than those with shorter durations of deafness, but still continued to improve with increased implant experience.
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Affiliation(s)
- L Geier
- Advanced Bionics Corporation, Sylmar, California 91342, USA
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Abstract
When cognitive scientists apply computational theory to the problem of phenomenal consciousness, as many have been doing recently, there are two fundamentally distinct approaches available. Consciousness is to be explained either in terms of the nature of the representational vehicles the brain deploys or in terms of the computational processes defined over these vehicles. We call versions of these two approaches vehicle and process theories of consciousness, respectively. However, although there may be space for vehicle theories of consciousness in cognitive science, they are relatively rare. This is because of the influence exerted, on the one hand, by a large body of research that purports to show that the explicit representation of information in the brain and conscious experience are dissociable, and on the other, by the classical computational theory of mind--the theory that takes human cognition to be a species of symbol manipulation. Two recent developments in cognitive science combine to suggest that a reappraisal of this situation is in order. First, a number of theorists have recently been highly critical of the experimental methodologies used in the dissociation studies--so critical, in fact, that it is no longer reasonable to assume that the dissociability of conscious experience and explicit representation has been adequately demonstrated. Second, classicism, as a theory of human cognition, is no longer as dominant in cognitive science as it once was. It now has a lively competitor in the form of connectionism; and connectionism, unlike classicism, does have the computational resources to support a robust vehicle theory of consciousness. In this target article we develop and defend this connectionist vehicle theory of consciousness. It takes the form of the following simple empirical hypothesis: phenomenal experience consists of the explicit representation of information in neurally realized parallel distributed processing (PDP) networks. This hypothesis leads us to reassess some common wisdom about consciousness, but, we argue, in fruitful and ultimately plausible ways.
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Affiliation(s)
- G O'Brien
- Department of Philosophy, University of Adelaide, Adelaide, South Australia 5005, Australia.
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Abstract
Two experiments were conducted to assess the effect of the rate of sinusoidal amplitude modulation (SAM) of a masker tone on detection of SAM of a probe tone (experiment 1) or on SAM-rate discrimination for the probe tone (experiment 2). When modulated at the same rate as the probe, the masker interfered with both the detection of probe modulation and the discrimination of the rate of probe modulation. The interference was obtained when the masker was either higher or lower in frequency than the probe (the probe and masker were separated by 2 oct). The amount of interference in detecting probe modulation (experiment 1) decreased as the common base rate of modulation was increased from 5 to 200 Hz. For rate discrimination (experiment 2), the amount of interference remained approximately the same for base rates of 2-40 Hz, the range over which rate discrimination was measured. In both experiments, the amount of interference was reduced when the masker was modulated at a different rate than the probe.
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Affiliation(s)
- W A Yost
- Parmly Hearing Institute, Loyola University, Chicago, Illinois 60626
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Ladusans EJ, Campalani G, Parsons JM, Qureshi SA, Opie J, Baker EJ, Tynan M, Deverall PB. Recurrence of aortic coarctation following repair by re-implantation of the subclavian artery. Int J Cardiol 1989; 23:321-5. [PMID: 2737776 DOI: 10.1016/0167-5273(89)90191-5] [Citation(s) in RCA: 5] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Four patients mean age six months, range 11 days to 2 years, underwent repair of aortic coarctation by the technique of reimplantation of the subclavian artery (Mendonca repair). All developed re-coarctation within six months of an initially successful repair.
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Affiliation(s)
- E J Ladusans
- Department of Paediatric Cardiology, Guy's Hospital, London, U.K
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