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101.
102.
Christopher M. Frost Daniel C. Ursu Shane M. Flattery Andrej Nedic Cheryl A. Hassett Jana D. Moon Patrick J. Buchanan R. Brent Gillespie Theodore A. Kung Stephen W. P. Kemp Paul S. Cederna Melanie G. Urbanchek 《Journal of neuroengineering and rehabilitation》2018,15(1):108
Introduction
Regenerative peripheral nerve interfaces (RPNIs) are biological constructs which amplify neural signals and have shown long-term stability in rat models. Real-time control of a neuroprosthesis in rat models has not yet been demonstrated. The purpose of this study was to: a) design and validate a system for translating electromyography (EMG) signals from an RPNI in a rat model into real-time control of a neuroprosthetic hand, and; b) use the system to demonstrate RPNI proportional neuroprosthesis control.Methods
Animals were randomly assigned to three experimental groups: (1) Control; (2) Denervated, and; (3) RPNI. In the RPNI group, the extensor digitorum longus (EDL) muscle was dissected free, denervated, transferred to the lateral thigh and neurotized with the residual end of the transected common peroneal nerve. Rats received tactile stimuli to the hind-limb via monofilaments, and electrodes were used to record EMG. Signals were filtered, rectified and integrated using a moving sample window. Processed EMG signals (iEMG) from RPNIs were validated against Control and Denervated group outputs.Results
Voluntary reflexive rat movements produced signaling that activated the prosthesis in both the Control and RPNI groups, but produced no activation in the Denervated group. Signal-to-Noise ratio between hind-limb movement and resting iEMG was 3.55 for Controls and 3.81 for RPNIs. Both Control and RPNI groups exhibited a logarithmic iEMG increase with increased monofilament pressure, allowing graded prosthetic hand speed control (R2?=?0.758 and R2?=?0.802, respectively).Conclusion
EMG signals were successfully acquired from RPNIs and translated into real-time neuroprosthetic control. Signal contamination from muscles adjacent to the RPNI was minimal. RPNI constructs provided reliable proportional prosthetic hand control.103.
Kyle A Kemp Nancy Chan Brandi McCormack Kathleen Douglas-England 《Health services research》2015,50(4):982-997
ObjectiveTo identify factors associated with patients’ overall rating of inpatient hospital care.ConclusionsOur results are novel in the Canadian population. Several questions for future research have been generated, in addition to opportunities for quality improvement within our own organization. 相似文献
104.
Ellia Mezgueldi Aurlia Bertholet‐Thomas Solange Milazzo Michael Morris Justine Bacchetta Nicole Fabien Pierre Cochat Anthony P. Weetman Elizabeth Helen Kemp Alexandre Belot 《Clinical Case Reports》2015,3(10):809-813
Early diagnosis of potentially life‐threatening autoimmune polyendocrinopathy‐candidiasis‐ectodermal dystrophy (APECED) is crucial, but is often delayed due to the clinical heterogeneity of the disorder. Even in the absence of the classic disease triad of chronic mucocutaneous candidiasis, hypoparathyroidism, and adrenocortical insufficiency, a diagnosis of APECED should be considered in children who have hypoparathyroidism and chronic keratitis, with a past medical history showing a mild and transient Candida infection. 相似文献
105.
van Rensburg Susan J. Hattingh Coenraad Johannes Clint Moremi Kelebogile E. Peeters Armand V. van Heerden Carel J. Erasmus Rajiv T. Zemlin Annalise E. Kemp Merlisa C. Jaftha Mariaan Khine Aye Aye Potocnik Felix C.V. Whati Lindiwe Engel-Hills Penelope van Toorn Ronald Kotze Maritha J. 《Metabolic brain disease》2021,36(6):1169-1181
Metabolic Brain Disease - In Part I of this Review we evaluated the scientific evidence for a Metabolic Model of multiple sclerosis (MS). Part II outlines the implementation of an adaptive... 相似文献
106.
P H Kleinman S Y Kang D S Lipton G E Woody J Kemp R B Millman 《The American journal of drug and alcohol abuse》1992,18(1):29-43
Retention in outpatient psychotherapy of 148 crack and cocaine abusers was examined. The clients were predominantly Black (63%) and Hispanic (21%), predominantly male (87%), and the majority (66%) had completed no more than 12 years of high school. Clients entered treatment in a low-cost treatment center in New York City between June 1987 and November 1988. Forty-two percent (62) of the subjects were seen for one or two research interviews only, and did not return to begin therapy. Of the 86 persons who came to at least one therapy session, 30% (26) dropped out before the third session, 28% (24) dropped out between the third and fifth sessions, and 42% (36) were retained for six or more sessions. Short-term and longer-term retentions were analyzed separately, using a battery including sociodemographic variables, treatment history, psychiatric symptomatology, number of arrests, and drug use variables. None of the variables considered was significantly related to short-term retention. There were large although not significant differences in longer term retention by therapist. Longer-term retention was associated significantly with being White (contrasted with being Black) and being young. Nonsignificant but large associations were found between longer-term retention and having few arrests, being Hispanic (contrasted with being Black), and having low SCL-90 scores. Results are compared with previous findings about retention in drug and alcohol treatment. It is suggested that future research on retention in treatment focus less on client variables and more on therapist and program variables. 相似文献
107.
108.
P J Thompson M W Kemp W A McAllister M Turner-Warwick 《British journal of diseases of the chest》1983,77(3):293-298
Eighteen patients with airways obstruction were given slow release theophylline and were then investigated to determine the influence of a standard meal upon the serum levels achieved over the ensuing 12-hour period. After food the peak to trough differences were decreased and the serum levels were significantly lower over the first 6 hours. In this study, the patients were given 10 mg/kg/day of slow release theophylline and none subsequently was found to have toxic levels, therefore this was considered to be a reasonable dose with which to initiate therapy in adults with uncomplicated airflow limitation. However even under the strictly controlled conditions of the study there were wide variations between individuals in the blood levels achieved and serum monitoring is necessary to use theophylline in an optimal fashion. 相似文献
109.
E. Helen Kemp 《Autoimmunity》2013,46(4):287-290
Genetic and environmental factors are believed to influence development of systemic lupus erythematosus (SLE). Endogenous retroviruses (ERV) correspond to the integrated proviral form of infectious retroviruses, which are trapped within the genome due to mutations. ERV represent a key molecular link between the host genome and infectious viral particles. ERV-encoded proteins are recognized by antiviral immune responses and become targets of autoreactivity. Alternatively, ERV protein may influence cellular processes and the life cycle of infectious viruses. As examples, the HRES-1 human ERV encodes a 28-kDa nuclear autoantigen and a 24-kDa small GTP-ase, termed HRES-1/Rab4. HRES-1/p28 is a nuclear autoantigen recognized by cross-reactive antiviral antibodies, while HRES-1/Rab4 regulates surface expression of CD4 and the transferrin receptor (TFR) through endosome recycling. Expression of HRES-1/Rab4 is induced by the tat gene of HIV-1, which in turn down-regulates expression of CD4 and susceptibility to re-infection by HIV-1. CD4 and the TFR play essential roles in formation of the immunological synapse (IS) during normal T-cell activation by a cognate MHC class II peptide complex. The key intracellular transducer of T-cell activation, Lck, is brought to the IS via binding to CD4. T-cell receptorζ (TCRζ) chain binds to the TFR. Abnormal T-cell responses in SLE have been associated with reduced lck and TCRζ chain levels. HRES-1 is centrally located on chromosome 1 at q42 relative to lupus-linked microsatellite markers and polymorphic HRES-1 alleles have been linked to the development of SLE. 1q42 is one of the three most common fragile sites in the human genome, and is inducible by DNA demethylation, a known mechanism of retroviral gene activation. Molecular mimicry and immunomodulation by a ERV, such as HRES-1, may contribute to self-reactivity and abnormal T and B-cell functions in SLE. 相似文献
110.
Huan Lan Xueling Suo Wenbin Li Nannan Li Junying Li Jiaxin Peng Du Lei John A. Sweeney Graham J. Kemp Rong Peng Qiyong Gong 《Human brain mapping》2021,42(10):3156
Neuroimaging studies using a variety of techniques have demonstrated abnormal patterns of spontaneous brain activity in patients with essential tremor (ET). However, the findings are variable and inconsistent, hindering understanding of underlying neuropathology. We conducted a meta‐analysis of whole‐brain resting‐state functional neuroimaging studies in ET compared to healthy controls (HC), using anisotropic effect‐size seed‐based d mapping, to identify the most consistent brain activity alterations and their relation to clinical features. After systematic literature search, we included 13 studies reporting 14 comparisons, describing 286 ET patients and 254 HC. Subgroup analyses were conducted considering medication status, head tremor status, and methodological factors. Brain activity in ET is altered not only in the cerebellum and cerebral motor cortex, but also in nonmotor cortical regions including prefrontal cortex and insula. Most of the results remained unchanged in subgroup analyses of patients with head tremor, medication‐naive patients, studies with statistical threshold correction, and the large subgroup of studies using functional magnetic resonance imaging. These findings not only show consistent and robust abnormalities in specific brain regions but also provide new information on the biology of patient heterogeneity, and thus help to elucidate the pathophysiology of ET. 相似文献