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1.
J Fish Dis ; 41(2): 223-232, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28836670

RESUMO

The aim of this study was to describe two epizootics of high mortalities from infection with Streptococcus agalactiae, occurring in captive rays held in a marine display aquarium in south-east Queensland, Australia, in 2009 and 2010. Five different species of rays were affected, including mangrove whiprays (Himantura granulata), estuary rays (Dasyatis fluviorum), eastern shovelnose rays (Aptychotrema rostrata), white-spotted eagle rays (Aetobatus narinari) and blue-spotted mask rays (Neotrygon kuhlii). This report describes the history of both epizootics including collection, quarantine and husbandry of rays, the disease epizootics, clinico-pathological features of the disease, antimicrobial therapy, autogenous vaccine production, and laboratory studies including clinical and histopathology, bacteriology, PCR, molecular serotyping and sequencing of the bacterium S. agalactiae.


Assuntos
Epidemias/veterinária , Doenças dos Peixes/epidemiologia , Rajidae , Infecções Estreptocócicas/veterinária , Streptococcus agalactiae/fisiologia , Animais , Anti-Infecciosos/uso terapêutico , Vacinas Bacterianas/imunologia , DNA Bacteriano/genética , DNA Ribossômico/genética , Doenças dos Peixes/tratamento farmacológico , Doenças dos Peixes/patologia , Reação em Cadeia da Polimerase/veterinária , Quarentena/veterinária , Queensland/epidemiologia , Análise de Sequência de DNA/veterinária , Infecções Estreptocócicas/tratamento farmacológico , Infecções Estreptocócicas/epidemiologia , Infecções Estreptocócicas/patologia , Streptococcus agalactiae/imunologia
2.
Aust Vet J ; 95(4): 118-122, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28346672

RESUMO

CASE REPORT: Cases of bilateral anterior nasal atresia, sometimes referred to as arhinia or partial arhinia, are extremely rare in cattle and have only been reported as single events. This report describes the birth of 16 Holstein Friesian calves over a 3-month period, all affected with bilateral atresia of the nares and anterior nasal cavity, with 2 calves having additional severe deviation of the nasomaxillary bones and nasal septum. One affected calf was born with an anatomically normal twin. Parentage testing demonstrated that a single Holstein Friesian bull sired all cases tested. CONCLUSION: This is the first report of multiple cases of bilateral anterior nasal atresia in cattle with evidence that demonstrates a heritable condition.


Assuntos
Doenças dos Bovinos/genética , Anormalidades Congênitas/veterinária , Nariz/anormalidades , Animais , Cruzamento , Bovinos , Doenças dos Bovinos/congênito , Doenças dos Bovinos/patologia , Anormalidades Congênitas/genética , Anormalidades Congênitas/patologia , Feminino , Masculino , Repetições de Microssatélites , Nariz/patologia , Gêmeos
3.
Scand J Med Sci Sports ; 26(4): 432-40, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25818526

RESUMO

Biomechanical studies of rugby union scrummaging have focused on kinetic and kinematic analyses, while muscle activation strategies employed by front-row players during scrummaging are still unknown. The aim of the current study was to investigate the activity of spinal muscles during machine and live scrums. Nine male front-row forwards scrummaged as individuals against a scrum machine under "crouch-touch-set" and "crouch-bind-set" conditions, and against a two-player opposition in a simulated live condition. Muscle activities of the sternocleidomastoid, upper trapezius, and erector spinae were measured over the pre-engagement, engagement, and sustained-push phases. The "crouch-bind-set" condition increased muscle activity of the upper trapezius and sternocleidomastoid before and during the engagement phase in machine scrummaging. During the sustained-push phase, live scrummaging generated higher activities of the erector spinae than either machine conditions. These results suggest that the pre-bind, prior to engagement, may effectively prepare the cervical spine by stiffening joints before the impact phase. Additionally, machine scrummaging does not replicate the muscular demands of live scrummaging for the erector spinae, and for this reason, we advise rugby union forwards to ensure scrummaging is practiced in live situations to improve the specificity of their neuromuscular activation strategies in relation to resisting external loads.


Assuntos
Músculos do Dorso/fisiologia , Futebol Americano/fisiologia , Músculos do Pescoço/fisiologia , Coluna Vertebral/fisiologia , Fenômenos Biomecânicos , Eletromiografia , Humanos , Masculino , Adulto Jovem
4.
J Agric Saf Health ; 21(3): 173-85, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26373215

RESUMO

The NIOSH cost-effective roll-over protective structure (CROPS) demonstration project sought to determine whether three prototype roll-over protective structures (ROPS) designed to be retrofitted on Ford 8N, Ford 3000, Ford 4000, and Massey Ferguson 135 tractors could be installed in the field and whether they would be acceptable by the intended end users (farmers). There were a total of 50 CROPS. demonstrators (25 in New York and 25 in Virginia), with 45 observers attending the New York CROPS demonstrations and 36 observers attending the Virginia CROPS demonstrations, for a total of 70 participants in New York and 61 in Virginia. The oldest retrofitted tractors were 77 to 62 years old, while the newest retrofitted tractors were 40 to 37 years old. The most frequently retrofitted tractor in the CROPS demonstration project was a Ford 3000 series tractor (n = 19; 38%), followed by Ford 4000 (n = 11; 22%), Massey Ferguson 135 (n = 11; 22%), and Ford 8N (n = 9; 18%). A major issue of CROPS retrofitting was the rear wheel fenders. The effort involved in disassembling the fenders (removing the old bolts was often faster by cutting them with a torch), modifying the fender mounting brackets, and then reinstalling the fenders with the CROPS generally required the most time. In addition, various other semi-permanent equipment attachments, such as front-end loaders, required additional time and effort to fit with the CROPS. Demonstrators were asked to rank the reasons why they had not retrofitted their tractors with ROPS until they had enrolled in the CROPS demonstration program. ROPS "cost too much" was ranked as the primary reason for participants in both states (80% for New York and 88% for Virginia). The second highest ranked reasons were "ROPS wasn't available" for Virginia (80%) and "hassle to find ROPS" for New York (69%). The third highest ranked reasons were "not enough time to find ROPS" for New York (67%) and "hassle to find ROPS" for Virginia (79%). All demonstrators and observers indicated that they were glad to have participated in the CROPS project.


Assuntos
Acidentes de Trabalho/prevenção & controle , Agricultura/instrumentação , National Institute for Occupational Safety and Health, U.S. , Equipamentos de Proteção , Segurança de Equipamentos/economia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , National Institute for Occupational Safety and Health, U.S./normas , New York , Equipamentos de Proteção/economia , Estados Unidos , Virginia
6.
Carbohydr Polym ; 106: 460-8, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24721102

RESUMO

The ß-D-Glc Yariv reagent is frequently used to isolate and to study the structure of arabinogalactan-proteins with the arabinogalactan type II structure. The present paper describes the aggregation features of the Yariv reagent in water, salt solutions and in organic solvents as determined by NMR, absorption spectroscopy and light scattering experiments. The results indicate that in water the Yariv reagent forms aggregates of up to 300 units and in 1% aqueous NaCl the degree of aggregation is approx. 150. The aggregates are formed both by H-bonds and hydrophobic interactions, the former appearing to be of most importance in water. The interaction between the Yariv reagent and an AGP fraction from gum arabic, showed a degree of aggregation of the Yariv reagent when using 1% NaCl to be of approx. 150 units, whereas disruption of the aggregate took place in 10% NaCl with an aggregation number of approx. 100. Partial acid hydrolysis of an AGP from gum Arabic (Acacia Senegal) and analyses of the linkage types remaining indicated that a certain length of (1→3)-ß-linked galactose units was necessary for binding between the Yariv reagent and the AGP. This is in accordance to what also was recently observed by Kitazawa et al. (2013).


Assuntos
Glucosídeos/química , Goma Arábica/química , Mucoproteínas/química , Floroglucinol/análogos & derivados , Difusão , Dimetil Sulfóxido/química , Dimetilformamida/química , Guanidina/química , Mucoproteínas/isolamento & purificação , Ressonância Magnética Nuclear Biomolecular , Floroglucinol/química , Proteínas de Plantas/química , Proteínas de Plantas/isolamento & purificação , Espalhamento de Radiação , Cloreto de Sódio/química , Solventes/química , Ureia/química , Água/química
7.
Anim Cogn ; 17(1): 113-25, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23820935

RESUMO

Perceptuomotor functions that support using hand tools can be examined in other manipulation tasks, such as alignment of objects to surfaces. We examined tufted capuchin monkeys' and chimpanzees' performance at aligning objects to surfaces while managing one or two spatial relations to do so. We presented six subjects of each species with a single stick to place into a groove, two sticks of equal length to place into two grooves, or two sticks joined as a T to place into a T-shaped groove. Tufted capuchins and chimpanzees performed equivalently on these tasks, aligning the straight stick to within 22.5° of parallel to the groove in approximately half of their attempts to place it, and taking more attempts to place the T stick than two straight sticks. The findings provide strong evidence that tufted capuchins and chimpanzees do not reliably align even one prominent axial feature of an object to a surface, and that managing two concurrent allocentric spatial relations in an alignment problem is significantly more challenging to them than managing two sequential relations. In contrast, humans from 2 years of age display very different perceptuomotor abilities in a similar task: they align sticks to a groove reliably on each attempt, and they readily manage two allocentric spatial relations concurrently. Limitations in aligning objects and in managing two or more relations at a time significantly constrain how nonhuman primates can use hand tools.


Assuntos
Cebus/psicologia , Pan troglodytes/psicologia , Comportamento de Utilização de Ferramentas , Animais , Feminino , Masculino , Desempenho Psicomotor
8.
Artigo em Inglês | MEDLINE | ID: mdl-25570742

RESUMO

Over the last decade the changing healthcare environment has required hospitals and specifically Biomedical Engineering to critically evaluate, optimize and adapt their operations. The focus is now on new technologies, changes to the environment of care, support requirements and financial constraints. Memorial Sloan Kettering Cancer Center (MSKCC), an NIH-designated comprehensive cancer center, has been transitioning to an increasing outpatient care environment. This transition is driving an increase in-patient acuity coupled with the need for added urgency of support and response time. New technologies, regulatory requirements and financial constraints have impacted operating budgets and in some cases, resulted in a reduction in staffing. Specific initiatives, such as the Joint Commission's National Patient Safety Goals, requirements for an electronic medical record, meaningful use and ICD10 have caused institutions to reevaluate their operations and processes including requiring Biomedical Engineering to manage new technologies, integrations and changes in the electromagnetic environment, while optimizing operational workflow and resource utilization. This paper addresses the new and expanding responsibilities and approach of Biomedical Engineering organizations, specifically at MSKCC. It is suggested that our experience may be a template for other organizations facing similar problems. Increasing support is necessary for Medical Software - Medical Device Data Systems in the evolving wireless environment, including RTLS and RFID. It will be necessary to evaluate the potential impact on the growing electromagnetic environment, on connectivity resulting in the need for dynamic and interactive testing and the growing demand to establish new and needed operational synergies with Information Technology operations and other operational groups within the institution, such as nursing, facilities management, central supply, and the user departments.


Assuntos
Tecnologia Biomédica , Engenharia Biomédica , Atenção à Saúde , Sistemas de Comunicação no Hospital , Hospitais , Humanos , Serviço Hospitalar de Engenharia e Manutenção , Assistência ao Paciente , Melhoria de Qualidade , Software , Tecnologia sem Fio
11.
Aust Vet J ; 91(4): 143-9, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23521099

RESUMO

Three ponies continuously grazed a pasture containing an estimated 24% Indigofera spicata (wet weight basis) for 4-6 weeks in April and May 2004. They developed ataxia, paresis, depression, muscle fasciculations, dysphagia, ptyalism and halitosis. Two also developed corneal opacity. One pony recovered with supportive treatment, but the other two were euthanased and necropsied. Neuropathology was not present in either case, but both livers had periacinar and periportal lymphocytic infiltrations and hydropic degeneration of mid-zonal hepatocytes, with mild to moderate periacinar necrosis also evident in one. The I. spicata contained 2.66 mg 3-nitropropionic acid (3-NPA)/g dry matter and 1.5 mg indospicine/g dry matter. Indospicine, but not 3-NPA, was detected in serum from both of the euthanased ponies and indospicine was detected in heart, liver and muscle from the one pony in which this assay was performed. The clinical syndrome closely resembled 'Birdsville horse disease' caused by I. linnaei and was similar to that reported in horses poisoned by the closely related species I. hendecaphylla and to 3-NPA poisoning of other animals, including humans. 3-NPA is thought to cause this neurological syndrome. To our knowledge, this is the first authenticated report of I. spicata poisoning in grazing animals. We also report here the first published evidence that 3-NPA and indospicine exist in naturalised I. spicata in Australia and of the formation of indospicine residues in tissues of animals grazing paddocks infested with I. spicata.


Assuntos
Doenças dos Cavalos/diagnóstico , Indigofera/intoxicação , Intoxicação por Plantas/veterinária , Animais , Evolução Fatal , Feminino , Cavalos , Masculino , Exame Neurológico/veterinária , Intoxicação por Plantas/diagnóstico
13.
J Appl Microbiol ; 113(4): 757-66, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22817383

RESUMO

AIMS: The aim of this project was to validate a method to deliver a reproducible, selected dose of infective bioaerosol through a respiratory protective technology to an animal that exhibits a proportional clinical response. METHODS AND RESULTS: The Controlled Aerosol Test System (CATS) was designed to generate and condition a viable infective aerosol, pass it through a treatment technology and thence to the breathing zone of a mouse constrained in a Nose-Only Inhalation Exposure System (NOIES). A scanning mobility particle sizer and impingers at sampling ports were used to show that viability is preserved and particle size distribution (PSD) is acceptably uniform throughout the open CATS, including the 12 ports of the NOIES, and that a particle filter used caused the expected attenuation of particle counts. CONCLUSIONS: Controlled Aerosol Test System delivers uniformly to mice constrained in the NOIES a selectable dose of viral bioaerosol whose PSD and viable counts remain consistent for an hour. SIGNIFICANCE AND IMPACT OF THE STUDY: This study's characterization of CATS provides a new test system in which a susceptible small-animal model can be used as the detector in a quantitative method to evaluate the ability of respiratory protective technologies to attenuate the infectivity of an inspired pathogenic aerosol. This provides a major improvement over the use of viable bioaerosol collectors (e.g. impactors and impingers), which provide data that are difficult to relate to the attenuation of pathogenicity.


Assuntos
Aerossóis/análise , Câmaras de Exposição Atmosférica , Exposição por Inalação , Administração por Inalação , Animais , Bacillus , Desenho de Equipamento , Filtração/instrumentação , Levivirus , Camundongos , Modelos Animais , Nariz , Tamanho da Partícula , Sistema Respiratório
14.
Aust Vet J ; 89(11): 452-7, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22008125

RESUMO

A juvenile offshore bottlenose dolphin (Tursiops truncatus) was found stranded with neurological signs and unable to swim or float unassisted. It subsequently died, succumbing to a combination of severe pneumonia and encephalitis. Morbillivirus serum neutralisation test serology was positive (titre 1:16) for cetacean morbillivirus and negative for both phocine distemper virus and canine distemper virus. There was concurrent thymic and lymph node lymphoid depletion and necrosis, together with intranuclear and intracytoplasmic acidophilic viral inclusion bodies and multinucleate syncytia within multiple organs. Paramyxovirus capsids were identified in lung sections via electron microscopy and morbillivirus antigen was demonstrated within sections of lung, thymus and brain by immunohistochemistry. Reverse transcription-polymerase chain reaction for morbillivirus nucleoprotein (N) and phosphoprotein (P) genes were positive and phylogenetic gene product sequence analysis revealed 98% and 94% sequence identity to dolphin morbillivirus, respectively. To the authors' knowledge, this is the first report of a cetacean mortality due to morbillivirus infection occurring in the southern hemisphere. Morbillivirus infection should be included in the differential diagnosis of stranded live or dead cetaceans in Australian waters, particularly if animals display neurological signs.


Assuntos
Golfinho Nariz-de-Garrafa/virologia , Infecções por Morbillivirus/veterinária , Animais , Animais Recém-Nascidos , Evolução Fatal , Masculino , Morbillivirus/isolamento & purificação , Infecções por Morbillivirus/mortalidade
15.
J Perinatol ; 31(11): 722-9, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21372795

RESUMO

OBJECTIVE: To evaluate cerebrovascular autoregulation as a function of arterial blood pressure (ABP) in the critically ill, premature infant. STUDY DESIGN: A prospective observational pilot study was conducted in two tertiary care Neonatal Intensive-Care Units. Premature infants (n=23, ≤30 weeks estimated gestational age with invasive ABP monitoring) were enrolled and received routine care while undergoing continuous autoregulation monitoring, using the cerebral oximetry index (COx). The COx is a moving, linear correlation coefficient between cortical reflectance oximetry and ABP. COx values were stratified as a function of ABP for individual subject recordings and for the cohort. RESULT: The mean duration of autoregulation monitoring was 3.2 days (median: 2.97, range: 0.61-3.99). A total of 10 of 23 (43%) developed intraventricular hemorrhage and 1 of 23 (4%) developed periventricular leukomalacia by head ultrasound. No association was found between neurologic injury and percentage of the monitoring periods with autoregulation impairment (defined as COx>0.5). Lower ABP was associated with dysautoregulation (higher COx values, P<0.01). The percentage of time with impaired autoregulation was greater with lower ABP (P=0.013, Spearman r=0.51). CONCLUSION: All infants studied had periods with intact and periods with impaired cerebrovascular autoregulation, measured with the COx. Low ABP was associated with impaired autoregulation.


Assuntos
Pressão Sanguínea/fisiologia , Circulação Cerebrovascular/fisiologia , Homeostase/fisiologia , Recém-Nascido Prematuro/fisiologia , Monitorização Fisiológica , Dióxido de Carbono/sangue , Hemorragia Cerebral/fisiopatologia , Humanos , Recém-Nascido , Doenças do Prematuro/fisiopatologia , Recém-Nascido de muito Baixo Peso , Leucomalácia Periventricular/fisiopatologia , Oxigênio/sangue
16.
Leuk Lymphoma ; 52(5): 764-70, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21271864

RESUMO

Survival is reportedly worse in patients with cancer concurrently diagnosed with deep venous thrombosis. However, information on specific malignancies is limited. From a cohort study of male US veterans we identified incident cancer cases (n = 412,008) and compared survival patterns among those with versus without a history of deep venous thrombosis. Using Cox proportional hazard models, we estimated hazard ratios (HRs) and 95% confidence intervals as measures of the relative risk of dying. Individuals with (versus without) a concomitant deep venous thrombosis and cancer diagnosis had a higher risk of dying (HR = 1.38; 1.28-1.49). The most prominent excess mortality (HR = 1.29-2.55) was observed among patients diagnosed with deep venous thrombosis at the time of diagnosis of lung, gastric, prostate, bladder, or kidney cancer. Increased risk of dying was also found among cancer patients diagnosed with deep venous thrombosis 1 year (HR = 1.14; 1.07-1.22), 1-5 years (HR = 1.14; 1.10-1.19), and >5 years (HR = 1.27; 1.23-1.31) before cancer; this was true for most cancer sites (HR = 1.17-1.64). In summary, antecedent deep venous thrombosis confers a worse prognosis upon cancer patients. Advanced stage at diagnosis, treatment effects, lifestyle factors, and comorbidity could explain differences by cancer site and time frame between a prior deep venous thrombosis diagnosis and cancer outcome.


Assuntos
Neoplasias/epidemiologia , Trombose Venosa/epidemiologia , Negro ou Afro-Americano , Idoso , Estudos de Casos e Controles , Comorbidade , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/complicações , Neoplasias/mortalidade , Análise de Sobrevida , Taxa de Sobrevida , Estados Unidos , Trombose Venosa/complicações , Veteranos , População Branca
17.
Aust Vet J ; 88(4): 132-6, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20402700

RESUMO

We describe a fibrosarcoma in a 12-year-old Quarterhorse x Arabian gelding as a sequela to equine influenza vaccination. Shortly after the second vaccination, swelling at the site was noticed by the owner and it continued to increase in size over the following 6 months. Biopsy of the mass indicated a fibrosarcoma had developed at the vaccination site. It was approximately 20 cm in diameter and elevated well above the level of the skin. There was no clinical evidence of metastases to the lungs or local lymph nodes. Surgical resection of the mass was performed and the wound healed by first and second intention. Histopathological examination and immunohistochemical staining confirmed a myofibroblastic fibrosarcoma with multifocal osseous metaplasia. To the authors' knowledge, this is the first equine case of a vaccine-associated fibrosarcoma.


Assuntos
Fibrossarcoma/veterinária , Doenças dos Cavalos/induzido quimicamente , Vacinas contra Influenza/efeitos adversos , Neoplasias de Tecido Muscular/veterinária , Neoplasias de Tecidos Moles/veterinária , Animais , Fibrossarcoma/induzido quimicamente , Fibrossarcoma/cirurgia , Doenças dos Cavalos/cirurgia , Cavalos , Masculino , Neoplasias de Tecido Muscular/induzido quimicamente , Neoplasias de Tecido Muscular/cirurgia , Neoplasias de Tecidos Moles/induzido quimicamente , Neoplasias de Tecidos Moles/cirurgia , Resultado do Tratamento , Vacinação/efeitos adversos , Vacinação/veterinária
18.
J Small Anim Pract ; 50(9): 498-502, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19769672
19.
Osteoporos Int ; 19(10): 1457-64, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18351426

RESUMO

UNLABELLED: We measured bone mineral density (BMD) in senior athletes competing in running and swimming events and compared results to those of sedentary controls. Total body BMD was greatest among runners suggesting that moderate impact activities continue to play a role in maintaining skeletal integrity with age. INTRODUCTION: The role of moderate impact exercise in maintaining skeletal integrity as we age remains unclear. METHODS: To determine the effect of moderate impact exercise on skeletal integrity in the elderly, we recruited master athletes, including 44 runners (moderate impact exercise) and 43 swimmers, competing in the 2005 National Senior Olympic Games and 87 non-athletes, all over the age of 65 years. Height, weight, calcium, vitamin D intake, bone mineral density (BMD) of the total body, spine, hip (total hip, femoral neck, trochanter, intertrochanter), forearm (1/3 distal radius), and heel ultrasound, and Z-scores were characterized by mean +/- SD and compared by analysis of variance. T-scores were used to determine sites of osteopenia and osteoporosis. RESULTS: Total body BMD of runners was significantly greater than that of controls (1.11 +/- 0.13 versus 1.10 +/- 0.13 g/cm(2), p < 0.05) and marginally greater than that of swimmers when adjusted for age and weight. Heel ultrasound bone mass of runners was significantly greater than that of swimmers or controls. Runners also had higher BMD in the total hip, intertrochanter and 1/3 distal radius when compared to swimmers. CONCLUSION: These findings suggest that moderate impact exercise contributes to skeletal integrity in older age.


Assuntos
Envelhecimento/fisiologia , Densidade Óssea/fisiologia , Corrida/fisiologia , Natação/fisiologia , Idoso , Idoso de 80 Anos ou mais , Antropometria/métodos , Doenças Ósseas Metabólicas/fisiopatologia , Doenças Ósseas Metabólicas/prevenção & controle , Estudos Transversais , Feminino , Humanos , Masculino , Osteoporose/fisiopatologia , Osteoporose/prevenção & controle , Fatores Sexuais
20.
Med Eng Phys ; 28(7): 710-8, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16298543

RESUMO

AIM: The energy efficiency of FES-cycling in spinal cord injured subjects is very much lower than that of normal cycling, and efficiency is dependent upon the parameters of muscle stimulation. We investigated measures which can be used to evaluate the effect on cycling performance of changes in stimulation parameters, and which might therefore be used to optimise them. We aimed to determine whether oxygen cost and stimulation cost measurements are sensitive enough to allow discrimination between the efficacy of different activation ranges for stimulation of each muscle group during constant-power cycling. METHODS: We employed a custom FES-cycling ergometer system, with accurate control of cadence and stimulated exercise workrate. Two sets of muscle activation angles ("stimulation patterns"), denoted "P1" and "P2", were applied repeatedly (eight times each) during constant-power cycling, in a repeated measures design with a single paraplegic subject. Pulmonary oxygen uptake was measured in real time and used to determine the oxygen cost of the exercise. A new measure of stimulation cost of the exercise is proposed, which represents the total rate of stimulation charge applied to the stimulated muscle groups during cycling. A number of energy-efficiency measures were also estimated. RESULTS: Average oxygen cost and stimulation cost of P1 were found to be significantly lower than those for P2 (paired t-test, p<0.05): oxygen costs were 0.56+/-0.03l min-1 and 0.61+/-0.04l min-1 (mean+/-S.D.), respectively; stimulation costs were 74.91+/-12.15 mC min-1 and 100.30+/-14.78 mC min-1 (mean+/-S.D.), respectively. Correspondingly, all efficiency estimates for P1 were greater than those for P2. CONCLUSION: Oxygen cost and stimulation cost measures both allow discrimination between the efficacy of different muscle activation patterns during constant-power FES-cycling. However, stimulation cost is more easily determined in real time, and responds more rapidly and with greatly improved signal-to-noise properties than the ventilatory oxygen uptake measurements required for estimation of oxygen cost. These measures may find utility in the adjustment of stimulation patterns for achievement of optimal cycling performance.


Assuntos
Terapia por Estimulação Elétrica/métodos , Traumatismos da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/terapia , Engenharia Biomédica , Terapia por Estimulação Elétrica/instrumentação , Terapia por Estimulação Elétrica/estatística & dados numéricos , Teste de Esforço/instrumentação , Teste de Esforço/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Contração Muscular/fisiologia , Oxigênio/fisiologia , Paraplegia/fisiopatologia , Paraplegia/terapia
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