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1.
Int J Environ Health Res ; 33(10): 976-992, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35466819

RESUMO

To review the applicability and accessibility of physical activity guidelines for adults living with long-term conditions whilst shielding during the COVID-19. A narrative review with systematic methodology was conducted between 2015 and 2021, with two stages: 1) Search of electronic databases PubMed/Medline, Web of Science, PsycInfo, and Cinahl; 2) search of long-term condition organisations. Sixty-five articles were identified, where nine included specific guidelines during the COVID-19, 28 specific guidelines to individuals living with long-term conditions and 7 identified the utilization of online resources. Twenty-one long-term condition organizations websites were reviewed where all of them included a section regarding physical activity guidelines and seven referred to online and offline accessible resources during COVID-19. Accessibility and applicability were variable across academic databases and long-term conditions organisation websites. Findings could inform long-term condition policy and guidelines development to better and more relevant support people living with long-term conditions to be physically active.


Assuntos
COVID-19 , Adulto , Humanos , COVID-19/prevenção & controle , Exercício Físico
2.
J Sports Sci ; 37(11): 1235-1241, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30558476

RESUMO

Intermittent exposure to hypoxia can lead to improved endurance performance. Currently, it is unclear whether peripheral adaptions play a role in improving oxygen delivery and utilization following both training and detraining. This study aimed to characterize skeletal muscle blood flow (mBF), oxygen consumption (mV̇O2), and perfusion adaptations to i) 4-weeks handgrip training in hypoxic and normoxic conditions, and ii) following 4-weeks detraining. Using a randomised crossover design, 9 males completed 30-min handgrip training four times a week in hypoxic (14% FiO2 ~ 3250m altitude) and normoxic conditions. mBF, mV̇O2 and perfusion were assessed pre, post 4-weeks training, and following 4-weeks detraining. Hierarchical linear modelling found that mV̇O2 increased at a significantly faster rate (58%) with hypoxic training (0.09 mlO2·min-1 · 100g-1 per week); perfusion increased at a significantly (69%) faster rate with hypoxic training (3.72 µM per week). mBF did not significantly change for the normoxic condition, but there was a significant increase of 0.38 ml· min-1 · 100ml-1 per week (95% CI: 0.35, 0.40) for the hypoxic condition. During 4-weeks detraining, mV̇O2 and perfusion significantly declined at similar rates for both conditions, whereas mBF decreased significantly faster following hypoxic training. Four weeks hypoxic training increases the delivery and utilisation of oxygen in the periphery.


Assuntos
Antebraço/irrigação sanguínea , Hipóxia , Microcirculação , Músculo Esquelético/irrigação sanguínea , Consumo de Oxigênio , Condicionamento Físico Humano/métodos , Adaptação Fisiológica , Estudos Cross-Over , Antebraço/fisiologia , Força da Mão , Hemodinâmica , Humanos , Modelos Lineares , Masculino , Músculo Esquelético/fisiologia , Espectroscopia de Luz Próxima ao Infravermelho , Adulto Jovem
3.
Eur J Appl Physiol ; 117(3): 575-582, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28213750

RESUMO

PURPOSE: The purpose of this double-blind, placebo-controlled study was to examine the effect of two fish oil supplements, one high in EPA (750 mg EPA, 50 mg DHA) and one low in EPA (150 mg EPA, 100 mg DHA), taken acutely as a recovery strategy following EIMD. METHODS: Twenty-seven physically active males (26 ± 4 year, 1.77 ± 0.07 m, 80 ± 10 kg) completed 100 plyometric drop jumps to induce muscle damage. Perceptual (perceived soreness) and functional (isokinetic muscle strength at 60° and 180° s-1, squat jump performance and countermovement jump performance) indices of EIMD were recorded before, and 1, 24, 48, 72, and 96h after the damaging protocol. Immediately after the damaging protocol, volunteers ingested either a placebo (Con), a low-EPA fish oil (Low EPA) or a high-EPA fish oil (High EPA) at a dose of 1 g per 10 kg body mass. RESULTS: A significant group main effect was observed for squat jump, with the High EPA group performing better than Con and Low EPA groups (average performance decrement, 2.1, 8.3 and 9.8%, respectively), and similar findings were observed for countermovement jump performance, (average performance decrement, 1.7, 6.8 and 6.8%, respectively, p = 0.07). Significant time, but no interaction main effects were observed for all functional and perceptual indices measured, although large effect sizes demonstrate a possible ameliorating effect of high dose of EPA fish supplementation (effect sizes ≥0.14). CONCLUSION: This study indicates that an acute dose of high-EPA fish oil may ameliorate the functional changes following EIMD.


Assuntos
Exercício Físico , Ácidos Graxos Ômega-3/uso terapêutico , Mialgia/prevenção & controle , Adulto , Ácidos Graxos Ômega-3/administração & dosagem , Humanos , Masculino , Mialgia/tratamento farmacológico , Mialgia/etiologia
4.
Biol Sport ; 34(1): 57-61, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28416899

RESUMO

As children's natural activity patterns are highly intermittent in nature, and characterised by rapid changes from rest to vigorous physical activity, discontinuous exercise tests may be considered ecologically valid for this population group. This study compared the peak physiological responses from a discontinuous and continuous graded exercise test (GXT_D, GXT_C, respectively) during treadmill exercise in children. Twenty-one healthy children (9.6 ± 0.6 y) completed GXT_D and GXT_C in a randomised order, separated by 72-hours. Following each GXT, and after a 15-minute recovery, participants completed a verification test at 105% of the velocity attained at peak oxygen consumption (VO2peak). There were no differences in VO2peak (55.3 ± 8.2 cf. 54.4 ± 7.6 mL·kg-1·min-1) or maximal heart rate (202 ± 10 cf. 204 ± 8 b·min-1) between GXT_C and GXT_D, respectively (P>.05). Peak running speed (10.7 ± 0.9 cf. 12.1 ± 1.3 km·h-1) and respiratory exchange ratio (1.04 ± 0.05 cf. 0.92 ± 0.05) were however different between tests (P<.001). Although similar peak physiological values were revealed between GXT_C and the corresponding verification test (P>.05), VO2peak (53.3 ± 7.3 mL·kg-1·min-1) and heart rate (197 ± 13 b·min-1) were significantly lower in the GXT_D verification test (P<.05). In conclusion, a discontinuous GXT is an accurate measure of VO2peak in children aged 8 to 10 years and may be a valid alternative to a continuous GXT, despite its longer duration.

5.
Biol Sport ; 33(3): 269-75, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27601782

RESUMO

The self-paced maximal oxygen uptake (VO2max) test (SPV), which is based on the Borg 6-20 Ratings of Perceived Exertion (RPE) scale, allows participants to self-regulate their exercise intensity during a closed-loop incremental maximal exercise test. As previous research has assessed the utility of the SPV test within laboratory conditions, the purpose to this study was to assess the effect of trial familiarisation on the validity and reproducibility of a field-based, SPV test. In a cross-sectional study, fifteen men completed one laboratory-based graded exercise test (GXT) and three field-based SPV tests. The GXT was continuous and incremental until the attainment of VO2max. The SPV, which was completed on an outdoor 400m athletic track, consisted of five x 2 min perceptually-regulated (RPE11, 13, 15, 17 and 20) stages of incremental exercise. There were no differences in the VO2max reported between the GXT (63.5±10.1 ml·kg(-1)·min(-1)) and each SPV test (65.5±8.7, 65.4±7.0 and 66.7±7.7 ml·kg(-1)·min(-1) for SPV1, SPV2 and SPV3, respectively; P>.05). Similar findings were observed when comparing VO2max between SPV tests (P>.05). High intraclass correlation coefficients were reported between the GXT and the SPV, and between each SPV test (≥.80). Although participants ran faster and further during SPV3, a similar pacing strategy was implemented during all tests. This study demonstrated that a field-based SPV is a valid and reliable VO2max test. As trial familiarisation did not moderate VO2max values from the SPV, the application of a single SPV test is an appropriate stand-alone protocol for gauging VO2max.

6.
Perspect Public Health ; : 17579139231180746, 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37381897

RESUMO

AIM: The aim of this systematic review was to examine the effectiveness of community-based health literacy interventions in improving the health literacy of parents. METHODS: A systematic review of six databases - MEDLINE, PsycINFO, CINAHL, Cochrane Library, Embase, and Education Source - was conducted to identify relevant articles. Risk of bias was assessed using version two of the Cochrane risk of bias tool for randomised controlled trials or the Cochrane collaboration risk of bias in non-randomised studies of interventions. The study findings were grouped and synthesised following the synthesis without meta-analysis framework. RESULTS: Eleven community-based health literacy interventions for parents were identified. Study design included randomised controlled trials (n = 4), non-randomised studies with comparison group (n = 4), and non-randomised studies without a comparison group (n = 3). Interventions were delivered digitally, in person or a combination of the two. The risk of bias was high in over half the studies (n = 7). The main findings of the studies showed some potential for both in person and digital interventions to increase parental health literacy. Studies were heterogeneous preventing a meta-analysis. CONCLUSION: Community-based, health literacy interventions have been identified as potential methods for enhancing parental health literacy. Due to the small number of included studies and their potential for bias, these results must be interpreted with caution. This study emphasises the need for additional theory and evidence-based research on the long-term effects of community interventions.

7.
J Fish Dis ; 35(3): 173-86, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22324342

RESUMO

Ninety-three giant Queensland grouper, Epinephelus lanceolatus (Bloch), were found dead in Queensland, Australia, from 2007 to 2011. Most dead fish occurred in northern Queensland, with a peak of mortalities in Cairns in June 2008. In 2009, sick wild fish including giant sea catfish, Arius thalassinus (Rüppell), and javelin grunter, Pomadasys kaakan (Cuvier), also occurred in Cairns. In 2009 and 2010, two disease epizootics involving wild stingrays occurred at Sea World marine aquarium. Necropsy, histopathology, bacteriology and PCR determined that the cause of deaths of 12 giant Queensland grouper, three wild fish, six estuary rays, Dasyatis fluviorum (Ogilby), one mangrove whipray, Himantura granulata (Macleay), and one eastern shovelnose ray, Aptychotrema rostrata (Shaw), was Streptococcus agalactiae septicaemia. Biochemical testing of 34 S. agalactiae isolates from giant Queensland grouper, wild fish and stingrays showed all had identical biochemical profiles. The 16S rRNA gene sequences of isolates confirmed all isolates were S. agalactiae; genotyping of selected S. agalactiae isolates showed the isolates from giant Queensland grouper were serotype Ib, whereas isolates from wild fish and stingrays closely resembled serotype II. This is the first report of S. agalactiae from wild giant Queensland grouper and other wild tropical fish and stingray species in Queensland, Australia.


Assuntos
Doenças dos Peixes/microbiologia , Infecções Estreptocócicas/veterinária , Streptococcus agalactiae/fisiologia , Animais , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/patologia , Peixes , Genótipo , Queensland/epidemiologia , RNA Ribossômico 16S , Infecções Estreptocócicas/epidemiologia , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/patologia , Streptococcus agalactiae/genética , Streptococcus agalactiae/isolamento & purificação
8.
J Laryngol Otol ; 136(12): 1231-1236, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35189991

RESUMO

BACKGROUND: The introduction of transoral robotic surgery into routine management of patients is complex. It involves organisational, logistical and clinical challenges. This study presents our experience of implementing such a programme and provides a blueprint for other centres willing to establish similar services. METHODS: Implementation of the robotic surgery programme focused on several key domains: training, logistics, governance, multidisciplinary team awareness, pre-operative imaging, anaesthesia, post-operative care, finance, patient selection and consent. Programme outcomes were evaluated by assessing operative outcomes of the first 117 procedures performed. RESULTS: The success of the transoral robotic surgery programme has been possible because of the scrupulous planning phase before the first procedure, and the time invested on team awareness and training. CONCLUSION: Implementation of a new transoral robotic surgery service has led to: the development of a dedicated transoral robotic surgery patient care protocol, the performance of progressively more complex procedures, the inclusion of transoral robotic surgery training and the establishment of several research projects.


Assuntos
Neoplasias de Cabeça e Pescoço , Procedimentos Cirúrgicos Robóticos , Humanos , Procedimentos Cirúrgicos Robóticos/métodos , Neoplasias de Cabeça e Pescoço/cirurgia , Reino Unido
9.
J Environ Qual ; 51(3): 451-461, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35373848

RESUMO

Quantifying spatial and temporal fluxes of phosphorus (P) within and among agricultural production systems is critical for sustaining agricultural production while minimizing environmental impacts. To better understand P fluxes in agricultural landscapes, P-FLUX, a detailed and harmonized dataset of P inputs, outputs, and budgets, as well as estimated uncertainties for each P flux and budget, was developed. Data were collected from 24 research sites and 61 production systems through the Long-term Agroecosystem Research (LTAR) network and partner organizations spanning 22 U.S. states and 2 Canadian provinces. The objectives of this paper are to (a) present and provide a description of the P-FLUX dataset, (b) provide summary analyses of the agricultural production systems included in the dataset and the variability in P inputs and outputs across systems, and (c) provide details for accessing the dataset, dataset limitations, and an example of future use. P-FLUX includes information on select site characteristics (area, soil series), crop rotation, P inputs (P application rate, source, timing, placement, P in irrigation water, atmospheric deposition), P outputs (crop removal, hydrologic losses), P budgets (agronomic budget, overall budget), uncertainties associated with each flux and budget, and data sources. Phosphorus fluxes and budgets vary across agricultural production systems and are useful resources to improve P use efficiency and develop management strategies to mitigate environmental impacts of agricultural systems. P-FLUX is available for download through the USDA Ag Data Commons (https://doi.org/10.15482/USDA.ADC/1523365).


Assuntos
Agricultura , Fósforo , Canadá , Fósforo/análise , Solo , Estados Unidos , Água
10.
Scand J Med Sci Sports ; 21(6): e176-83, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21039898

RESUMO

This study assessed the effect of distance feedback on athletic performance, physiological and perceptual markers and the pacing strategies utilized during treadmill exercise. Thirteen men completed four self-paced 6 km treadmill time trials with either accurate, inaccurate or no distance feedback (NF). Inaccurate time trials involved participants receiving premature (PF) or delayed (DF) feedback, before or following the completion of each kilometer. The provision of accurate or inaccurate distance feedback (PF, DF) did not moderate the completion time or the rate of change in the ratings of perceived exertion (P>0.05). However, completion times were significantly slower when exercising with no distance feedback (P<0.001). Heart rate (HR), oxygen uptake (VO2) and running velocity all increased during the conditions (P<0.001). A significantly lower VO2 (up to 7%) and HR (up to 6%) were observed during NF. This study has demonstrated that athletic performance and perceptual and physiological responses are unaffected by inaccurate distance feedback. However, the study indicates that individuals may exercise at a lower metabolic intensity when running without distance feedback.


Assuntos
Adaptação Fisiológica/fisiologia , Desempenho Atlético/estatística & dados numéricos , Retroalimentação Psicológica/fisiologia , Corrida/psicologia , Adolescente , Tomada de Decisões , Teste de Esforço , Humanos , Masculino , Modelos Estatísticos , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Esforço Físico , Fatores de Tempo , Adulto Jovem
11.
Spinal Cord ; 49(1): 131-5, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20514056

RESUMO

STUDY DESIGN: Each participant completed an arm-crank ramp exercise test to volitional exhaustion. OBJECTIVE: To assess the utility of the rating of perceived exertion (RPE) to predict peak oxygen uptake (VO(2)peak) during arm ergometry in able-bodied participants and those with poliomyelitis. SETTING: University of Jordan, Amman, Jordan. PARTICIPANTS: In all, 16 able-bodied and 15 participants with poliomyelitis completed an arm-crank ramp exercise test to volitional exhaustion. MAIN OUTCOME MEASURES: The prediction of VO(2)peak is calculated by extrapolating the sub-maximal RPE and VO(2) values by linear regression to RPE 20. RESULTS: For the able-bodied participants, there were no significant differences between measured and predicted VO(2)peak from the three sub-maximal ranges of the RPE (RPEs before and including RPE 13, 15 and 17, P > 0.05). For the participants with poliomyelitis, the VO(2)peak predicted from RPEs before and including RPE 13 was significantly higher than measured VO(2)max (P < 0.05). The 95% limits of agreement of able-bodied participants for RPE 13, 15 and 17 (-3 ± 14, -1 ± 10 & 0 ± 8 ml kg(-1) min(-1), respectively) were lower than those observed for poliomyelitis participants (6 ± 19, 2 ± 12 and 1 ± 9 ml kg(-1) min(-1), respectively). CONCLUSION: This study has shown that the estimation of VO(2)peak from submaximal RPE during arm ergometry is generally more accurate in able-bodied participants in comparison with those with poliomyelitis.


Assuntos
Tolerância ao Exercício/fisiologia , Músculo Esquelético/metabolismo , Doenças Musculares/metabolismo , Doenças Musculares/reabilitação , Consumo de Oxigênio/fisiologia , Poliomielite/reabilitação , Adulto , Exercício Físico/fisiologia , Terapia por Exercício/métodos , Feminino , Humanos , Masculino , Músculo Esquelético/fisiopatologia , Poliomielite/complicações , Valor Preditivo dos Testes , Adulto Jovem
12.
Perfusion ; 26(2): 79-81, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21173035

RESUMO

We report a case of reduced cerebral oxygenation which had the possibility of leading to an adverse outcome if it had not been detected by the routine use of cerebral oximetry. This case study illustrates that an inadvertent re-adjustment of a single-stage venous cannula within the superior vena cava resulted only in the cerebral oximetry device alerting to a potential problem. All other monitoring devices remained within standard operating parameters, with no deviation throughout the duration of the incident.


Assuntos
Encéfalo/metabolismo , Procedimentos Cirúrgicos Cardíacos/métodos , Oximetria/métodos , Oxigênio/metabolismo , Idoso , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Humanos
13.
Hernia ; 25(2): 365-373, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33394253

RESUMO

PURPOSE: Myofascial release techniques at the time of complex hernia repair allow for tension-free closure of the midline fascia. Two common techniques are the open external oblique release (EOR) and the transversus abdominis release (TAR). Each technique has its reported advantages and disadvantages, but there have been few comparative studies. The purpose of this project was to compare the outcomes of these two myofascial release techniques. METHODS: The Americas Hernia Society Quality Collaborative (AHSQC) database was queried and produced a data set on 24 May 2018. All patients undergoing open incision hernia repair with an open EOR or TAR were evaluated, and outcomes were compared including hernia recurrence, quality of life, and 30-day wound-related complications. RESULTS: 3610 patients met the inclusion criteria of undergoing open incisional hernia repair (501 undergoing EOR and 3109 undergoing TAR). Seventy surgeons from 50 institutions contributed EOR patients, and 124 surgeons from 89 institutions contributed TAR patients with no differences between the two groups in surgeons' affiliation. Comparing open EOR and TAR showed no significant differences in hernia recurrence, quality of life, or 30-day surgical site infection rate. EOR had a significantly higher rate of surgical site occurrences compared with TAR (p < 0.05); however, this did not result in an increase in surgical site occurrences requiring procedural interventions. CONCLUSIONS: Equivalent outcomes were achieved using the EOR or TAR techniques in the open repair of incisional hernias. Both techniques offer consistently good outcomes and are important adjuncts in the repair of complex incisional hernias.


Assuntos
Hérnia Ventral , Hérnia Incisional , Músculos Abdominais/cirurgia , Hérnia Ventral/cirurgia , Herniorrafia/efeitos adversos , Humanos , Hérnia Incisional/cirurgia , Qualidade de Vida , Telas Cirúrgicas
14.
J Cell Biol ; 150(6): 1399-410, 2000 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-10995444

RESUMO

Dystrophin is a multidomain protein that links the actin cytoskeleton to laminin in the extracellular matrix through the dystrophin associated protein (DAP) complex. The COOH-terminal domain of dystrophin binds to two components of the DAP complex, syntrophin and dystrobrevin. To understand the role of syntrophin and dystrobrevin, we previously generated a series of transgenic mouse lines expressing dystrophins with deletions throughout the COOH-terminal domain. Each of these mice had normal muscle function and displayed normal localization of syntrophin and dystrobrevin. Since syntrophin and dystrobrevin bind to each other as well as to dystrophin, we have now generated a transgenic mouse deleted for the entire dystrophin COOH-terminal domain. Unexpectedly, this truncated dystrophin supported normal muscle function and assembly of the DAP complex. These results demonstrate that syntrophin and dystrobrevin functionally associate with the DAP complex in the absence of a direct link to dystrophin. We also observed that the DAP complexes in these different transgenic mouse strains were not identical. Instead, the DAP complexes contained varying ratios of syntrophin and dystrobrevin isoforms. These results suggest that alternative splicing of the dystrophin gene, which naturally generates COOH-terminal deletions in dystrophin, may function to regulate the isoform composition of the DAP complex.


Assuntos
Proteínas Associadas à Distrofina , Distrofina , Distrofias Musculares/metabolismo , Actinas/metabolismo , Animais , Sítios de Ligação/fisiologia , Núcleo Celular/patologia , Proteínas do Citoesqueleto/análise , Proteínas do Citoesqueleto/metabolismo , Modelos Animais de Doenças , Distrofina/química , Distrofina/genética , Distrofina/metabolismo , Éxons , Proteínas de Membrana/análise , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos mdx , Camundongos Transgênicos , Microssomos/química , Microssomos/metabolismo , Contração Muscular/genética , Fibras Musculares Esqueléticas/química , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/patologia , Proteínas Musculares/análise , Proteínas Musculares/metabolismo , Distrofias Musculares/patologia , Neuropeptídeos/análise , Neuropeptídeos/metabolismo , Estrutura Terciária de Proteína , Utrofina
15.
J Cell Biol ; 134(4): 873-84, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8769413

RESUMO

The functional significance of the actin-binding domain of dystrophin, the protein lacking in patients with Duchenne muscular dystrophy, has remained elusive. Patients with deletions of this domain (domain I) typically express low levels of the truncated protein. Whether the moderate to severe phenotypes associated with such deletions result from loss of an essential function, or from reduced levels of a functional protein, is unclear. To address this question, we have generated transgenic mice that express wild-type levels of a dystrophin deleted for the majority of the actin-binding domain. The transgene derived protein lacks amino acids 45-273, removing 2 of 3 in vitro identified actin interacting sites and part of hinge 1. Examination of the effect of this deletion in mice lacking wild-type dystrophin (mdx) suggests that a functional domain I is not essential for prevention of a dystrophic phenotype. However, in contrast to deletions in the central rod domain and to full-length dystrophin, both of which are functional at only 20% of wild-type levels, proteins with a deletion in domain I must be expressed at high levels to prevent a severe dystrophy. These results are also in contrast to the severe dystrophy resulting from truncation of the COOH-terminal domain that links dystrophin to the extracellular matrix. The mild phenotype observed in mice with domain I-deletions indicates that an intact actin-binding domain is not essential, although it does contribute to an important function of dystrophin. These studies also suggest the link between dystrophin and the subsarcolemmal cytoskeleton involves more than a simple attachment of domain I to actin filaments.


Assuntos
Distrofina/fisiologia , Distrofia Muscular Animal/patologia , Deleção de Sequência , Actinina/análise , Actinas/metabolismo , Animais , Diafragma/química , Diafragma/patologia , Diafragma/fisiopatologia , Distrofina/análise , Distrofina/genética , Distrofina/metabolismo , Expressão Gênica , Camundongos , Camundongos Endogâmicos mdx , Camundongos Transgênicos , Contração Muscular , Músculo Esquelético/química , Músculo Esquelético/patologia , Distrofia Muscular Animal/fisiopatologia , Fenótipo , Ligação Proteica , Sarcolema/química , Transgenes/genética
16.
J Cell Biol ; 142(6): 1461-71, 1998 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-9744877

RESUMO

Limb-girdle muscular dystrophy type 2D (LGMD 2D) is an autosomal recessive disorder caused by mutations in the alpha-sarcoglycan gene. To determine how alpha-sarcoglycan deficiency leads to muscle fiber degeneration, we generated and analyzed alpha-sarcoglycan- deficient mice. Sgca-null mice developed progressive muscular dystrophy and, in contrast to other animal models for muscular dystrophy, showed ongoing muscle necrosis with age, a hallmark of the human disease. Sgca-null mice also revealed loss of sarcolemmal integrity, elevated serum levels of muscle enzymes, increased muscle masses, and changes in the generation of absolute force. Molecular analysis of Sgca-null mice demonstrated that the absence of alpha-sarcoglycan resulted in the complete loss of the sarcoglycan complex, sarcospan, and a disruption of alpha-dystroglycan association with membranes. In contrast, no change in the expression of epsilon-sarcoglycan (alpha-sarcoglycan homologue) was observed. Recombinant alpha-sarcoglycan adenovirus injection into Sgca-deficient muscles restored the sarcoglycan complex and sarcospan to the membrane. We propose that the sarcoglycan-sarcospan complex is requisite for stable association of alpha-dystroglycan with the sarcolemma. The Sgca-deficient mice will be a valuable model for elucidating the pathogenesis of sarcoglycan deficient limb-girdle muscular dystrophies and for the development of therapeutic strategies for this disease.


Assuntos
Proteínas do Citoesqueleto/deficiência , Glicoproteínas de Membrana/deficiência , Distrofia Muscular Animal/etiologia , Proteínas de Neoplasias , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas de Transporte/biossíntese , Proteínas de Transporte/fisiologia , Proteínas do Citoesqueleto/genética , DNA Complementar , Progressão da Doença , Distrofina/metabolismo , Técnicas de Transferência de Genes , Glicoproteínas/metabolismo , Glicoproteínas de Membrana/genética , Proteínas de Membrana/biossíntese , Proteínas de Membrana/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Dados de Sequência Molecular , Contração Muscular , Distrofia Muscular Animal/fisiopatologia , Sarcoglicanas , Sarcolema/metabolismo
17.
Science ; 204(4397): 1085-7, 1979 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-451552

RESUMO

Digitized electromyographic activity of transplanted extensor digitorum longus (EDL) muscles in cats differs from that of control EDL and anterior tibialis muscles lying adjacent to transplanted EDL muscles. In autotransplanted muscles, the cross-sectional area of the fibers shows a negative correlation with mean spike frequency and a positive correlation with mean amplitude. The mean frequency-amplitude products correlate with isometric tetanic tensions.


Assuntos
Músculos/transplante , Regeneração , Potenciais de Ação , Animais , Gatos , Eletrodos , Eletromiografia/métodos , Músculos/citologia , Músculos/fisiologia , Transplante Autólogo
20.
Sci Rep ; 9(1): 13743, 2019 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-31551449

RESUMO

Circadian rhythm disruption is one of the earliest biomarkers of Alzheimer's disease (AD), and there exists a bidirectional relationship by which dysfunctions in the circadian clock drive AD pathology and AD pathology drives circadian dysfunction. Casein kinase 1 (CK1) isoforms ε and δ, key circadian regulators, are significantly upregulated in AD and may contribute to AD pathogenesis. In the current studies, we have examined how inhibition of CK1ε/δ with PF-670462 (at 10 mg/kg, δ isoform selective, or 30 mg/kg, δ and ε selective) impacts regional Aß and circadian gene expression in 10-13 month old APP-PS1 mice and nontransgenic controls. We have also assessed circadian, cognitive, and affective behavioral correlates of these neural changes. At baseline, APP-PS1 mice showed a short period, as well as impaired cognitive performance in both prefrontal cortex and hippocampus-dependent tasks. Both doses of PF-670462 lengthened the period and improved affect, whereas only the higher dose improved cognition. Further, PF-670462 treatment produced a dose-dependent reduction in amyloid burden - overall Aß signal decreased in all three areas; in the prefrontal cortex and hippocampus, PF-670462 also reduced plaque size. Together, these findings support chronotherapy as a potential tool to improve behavior in AD.

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