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1.
J Digit Imaging ; 35(4): 938-946, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35293605

RESUMO

Diagnosis of brain tumor gliomas is a challenging task in medical image analysis due to its complexity, the less regularity of tumor structures, and the diversity of tissue textures and shapes. Semantic segmentation approaches using deep learning have consistently outperformed the previous methods in this challenging task. However, deep learning is insufficient to provide the required local features related to tissue texture changes due to tumor growth. This paper designs a hybrid method arising from this need, which incorporates machine-learned and hand-crafted features. A semantic segmentation network (SegNet) is used to generate the machine-learned features, while the grey-level co-occurrence matrix (GLCM)-based texture features construct the hand-crafted features. In addition, the proposed approach only takes the region of interest (ROI), which represents the extension of the complete tumor structure, as input, and suppresses the intensity of other irrelevant area. A decision tree (DT) is used to classify the pixels of ROI MRI images into different parts of tumors, i.e. edema, necrosis and enhanced tumor. The method was evaluated on BRATS 2017 dataset. The results demonstrate that the proposed model provides promising segmentation in brain tumor structure. The F-measures for automatic brain tumor segmentation against ground truth are 0.98, 0.75 and 0.69 for whole tumor, core and enhanced tumor, respectively.


Assuntos
Neoplasias Encefálicas , Glioma , Algoritmos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Glioma/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Redes Neurais de Computação
2.
Clin J Sport Med ; 30(1): 83-90, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31855916

RESUMO

BACKGROUND: Actovegin is a biological drug with a controversial history of use in the treatment of sports injuries during the past 60 years. Particular concerns have been raised about its ergogenic potential to enhance performance, but some of these have been based on little more than anecdote. OBJECTIVES: In this article, we review the most recent scientific evidence to determine the clinical efficacy, safety profile, and legal status of Actovegin. METHODS: We considered all studies directly commenting on experience with Actovegin use as the primary intervention within the past 10 years. Outcomes included mechanisms of action, clinical efficacy in enhancing muscle repair, any report of safety issues, and any evidence for ergogenic effect. RESULTS: Our database search returned 212 articles, abstracts were screened, and after inclusion/exclusion criteria were applied, 25 articles were considered: Publications included 11 primary research articles (7 in vitro studies and 4 clinical trials), 8 review articles, 5 editorials, and a single case report. CONCLUSIONS: Current literature is still yet to define the active compound(s) of Actovegin, but suggests that it shows antioxidant and antiapoptotic properties, and may also upregulate macrophage responses central to muscle repair. Clinical efficacy was supported by one new original research article, and the use of Actovegin to treat muscle injuries remains safe and supported. Two articles argued the ergogenic effect of Actovegin, but in vitro findings did not to translate to the outcomes of a clinical trial. An adequate and meaningful scientific approach remains difficult in a field where there is immense pressure to deliver cutting-edge therapies.


Assuntos
Antioxidantes/uso terapêutico , Traumatismos em Atletas/tratamento farmacológico , Heme/análogos & derivados , Músculo Esquelético/lesões , Antioxidantes/efeitos adversos , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Heme/efeitos adversos , Heme/farmacologia , Heme/uso terapêutico , Humanos , Macrófagos/efeitos dos fármacos , Substâncias para Melhoria do Desempenho/uso terapêutico
3.
Foot Ankle Surg ; 25(1): 59-62, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29409258

RESUMO

BACKGROUND: Our aim was to determine whether plasma levels of Tissue Factor (TF), Vascular Cell Adhesion Molecule 1 (VCAM-1), Interleukin 6 (IL-6) or D-dimer after foot and ankle injury could predict which patients would develop deep vein thrombosis (DVT). METHODS: Patients aged 18-60 years with acute foot and ankle injury had venous blood sample to measure TF, VCAM-1, IL-6 and D-dimer within 3 days of injury. Patients had bilateral lower limb venous ultrasound to assess for DVT on discharge from clinic. RESULTS: 21 of 77 patients were found to have DVT (27%). There was no statistically significant association between levels of TF, VCAM-1, IL-6 or D-dimer and subsequent development of DVT. CONCLUSION: Tissue Factor (TF), Vascular Cell Adhesion Molecule-1 (VCAM-1), Interleukin-6 (IL-6) and D-dimer levels were not associated with development deep vein thrombosis in patients with acute foot and ankle injury.


Assuntos
Traumatismos do Tornozelo/sangue , Citocinas/sangue , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Traumatismos do Pé/sangue , Trombose Venosa/sangue , Adolescente , Adulto , Traumatismos do Tornozelo/complicações , Biomarcadores/sangue , Feminino , Traumatismos do Pé/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Ultrassonografia , Trombose Venosa/etiologia , Adulto Jovem
4.
Foot Ankle Surg ; 24(1): 19-27, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29413769

RESUMO

BACKGROUND: Our aim was to determine the evidence for thromboprophylaxis for prevention of symptomatic venous thromboembolism (VTE) in adults with foot or ankle trauma treated with below knee cast or splint. Our secondary aim was to report major bleeding events. METHODS: MEDLINE and EMBASE databases were searched for randomized controlled trials from inception to 1st June 2015. RESULTS: Seven studies were included. All focused on low molecular weight heparin (LMWH). None found a statistically significant symptomatic DVT reduction individually. At meta-analysis LMWH was protective against symptomatic DVT (OR 0.29, 95% CI 0.09-0.95). Symptomatic pulmonary embolism affected 3/692 (0.43%). None were fatal. 86 patients required LMWH thromboprophylaxis to prevent one symptomatic DVT event. The overall incidence of major bleeding was 1 in 886 (0.11%). CONCLUSIONS: Low molecular weight heparin reduces the incidence of symptomatic VTE in adult patients with foot or ankle trauma treated with below knee cast or splint.


Assuntos
Traumatismos do Tornozelo/terapia , Anticoagulantes/uso terapêutico , Moldes Cirúrgicos/efeitos adversos , Traumatismos do Pé/terapia , Heparina de Baixo Peso Molecular/uso terapêutico , Tromboembolia Venosa/prevenção & controle , Traumatismos do Tornozelo/complicações , Traumatismos do Pé/complicações , Hemorragia/etiologia , Humanos , Prevenção Primária , Contenções/efeitos adversos , Tromboembolia Venosa/etiologia
5.
Foot Ankle Surg ; 23(3): 183-188, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28865588

RESUMO

BACKGROUND: Patients with foot and ankle trauma treated with cast are advised to perform toe movements to prevent venous thromboembolism (VTE). Our aim was to determine the effect of active toe movement on asymptomatic deep vein thrombosis (DVT) and venous calf pump function. METHODS: Patients aged 18-60 years with acute foot and ankle trauma requiring below knee non weight bearing cast were randomized to intervention (regular active toe movement) or control groups (n=100). Patients had bilateral lower limb venous ultrasound to assess for DVT on discharge from clinic. Patients requiring chemical thromboprophylaxis were excluded. RESULTS: 78 completed the study. 27% sustained asymptomatic DVT, with no statistically significant difference in calf pump function or DVT incidence between groups. All DVT's occurred in the injured lower limb. CONCLUSION: Active toe movement is not a viable strategy for thromboprophylaxis in patients with acute foot and ankle trauma treated with cast.


Assuntos
Traumatismos do Tornozelo/terapia , Moldes Cirúrgicos/efeitos adversos , Traumatismos do Pé/terapia , Fixação de Fratura/efeitos adversos , Modalidades de Fisioterapia , Trombose Venosa/prevenção & controle , Adolescente , Adulto , Feminino , Fixação de Fratura/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Movimento , Músculo Esquelético , Estudos Prospectivos , Fluxo Sanguíneo Regional , Articulação do Dedo do Pé , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/etiologia , Adulto Jovem
6.
Sports Biomech ; 21(9): 1021-1031, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32129721

RESUMO

Artificial turf (AT) is common at all levels of soccer and rugby. Employing an interdisciplinary design, this study aimed to examine the extent to which the negative attitude commonly expressed by players concerning AT is based on the difference in technique between AT and natural turf (NT), or due to pre-existing biases. Thirty professional soccer and rugby players performed a defined set of movements with masked and normal perception conditions on NT and AT. Two-dimensional kinematic analysis (100 Hz) of characteristics in parallel to a psychological assessment of the impact of cognitive bias for a playing surface was assessed. No significant interaction effects between the level of perception and surface type were found. For AT, contact time (CT) was shorter across conditions, while for NT rugby players had longer CT during acceleration/deceleration phases and shorter flight times. Pre-existing negative bias against AT was found during the normal perception trials in the technology acceptance model (Usefulness and Ease of Use) and the general preference questions on how much the athlete would like to play a game on it. The results suggest that opinion was not driven by surface characteristics, but by a cognitive bias, players brought with them to the pitch.


Assuntos
Futebol , Aceleração , Fenômenos Biomecânicos , Humanos , Percepção , Rugby
7.
Curr Sports Med Rep ; 10(4): 186-90, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23531892

RESUMO

Actovegin is a deproteinized serum extract of bovine origin, and in recent years it has been used widely in treating sport injuries with many anecdotal reports of success. However, the use of Actovegin in sport medicine has caused a substantial amount of controversy, especially concerning its supposed oxygen-enhancing capacity and an anecdotal belief that its use can increase an athlete's performance. In 2009, a sports physician was arrested with this "performance-enhancing drug," while an editorial in a sports medicine journal strongly questioned the evidence base for using this drug for acute muscle injury. There is also a report that suggested that Actovegin might have induced anaphylactic shock in a cyclist. In this review, we have systematically examined the current evidence on Actovegin. Its mechanism of action, clinical evidence, legal status with sports governing bodies, and its potential role in sport injuries will be discussed.


Assuntos
Antioxidantes/uso terapêutico , Heme/análogos & derivados , Medicina Esportiva , Antioxidantes/farmacologia , Traumatismos em Atletas/tratamento farmacológico , Heme/farmacologia , Heme/uso terapêutico , Humanos
8.
BMJ Open Sport Exerc Med ; 4(1): e000282, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29387443

RESUMO

OBJECTIVE: We aimed to explore the validity of applying current reference ranges of the enzyme creatine kinase (CK) when analysing the medical status of professional footballers and to offer a more functional CK reference range for professional footballers. METHODS: A sample of 27 professional male footballers competing in The Football League Championship was analysed. The single sample Wilcoxon signed-rank test was used to compare the CK distribution of the study group with that of a control group of military personnel reported in the literature. RESULTS: The median values for study group and the published control group were 284 U/L and 124 U/L, respectively (P<0.001) suggesting that the average CK activity of professional footballers is higher than that of the normal healthy military population. CONCLUSION: Ethnicity, sex, age and physical exercise are factors that likely influence CK levels among various populations. From our analysis, we recommend a new 95% reference interval of 64.9 U/L to 1971.7 U/L for professional footballers.

9.
BMJ Open Sport Exerc Med ; 2(1): e000134, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27900187

RESUMO

BACKGROUND: The premise of this study was to investigate if anthropometric variables such as mobility, proprioception, strength and modified Functional Movement Screen (mFMS) could be used as primary indicators of injury risk in an English Championship division football team. This study focused on moderate injuries occurring in the lower extremities, during the 2014/2015 competitive season. METHODS: To differentiate between minor, moderate and severe injuries, this study classified moderate injuries as an injury with an average injury severity of 2-28 days. This study is composed of 4 individual investigations. Each variable was assessed against 2 groups: injured (n=6) and non-injured (n=10). The 2 groups were compiled from the first team, with the criteria that each participant of this study required: full preseason assessment and injury history for the time period, 1 July 2014 to 19 March 2015. A Mann-Whitney U test (0.05% significance) was applied to statistically analyse if each variable showed any variation across the 2 groups. Effect size was estimated with Cliff's d. RESULTS: Strength asymmetry displayed significant difference (p=0.007), mobility, proprioception and mFMS did not (p=0.263, p=0.792 and p=0.181, respectively). Mean scores for mobility, proprioception, strength asymmetry and mFMS for injured versus non-injured players (effect size) were: 40.00 vs 38.00 (0.37), 10.33 vs 10.20 (0.10), 61.13 vs 30.40 (0.80) and 7.33 vs 8.90 (-0.4), respectively. CONCLUSIONS: This study found no relationship between mobility/proprioception and injury risk; however, strength asymmetry was statistically significant in predicting injury and mFMS exhibited enough positive difference for recommendation of further investigation.

10.
Ultrasound Med Biol ; 38(11): 1887-95, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22975033

RESUMO

Thirty-seven pathologic Achilles tendons from 27 patients were investigated by a three-dimensional (3-D) power Doppler ultrasound system. Both the volume of the neovascularity (VON) and the volume of Achilles tendon (VOAT) were investigated. VON-VOAT index (VVI), as the normalization of the neovascularization, was accordingly calculated. Patient's clinical indications were assessed using the visual analog scale for pain (VAS) and Victorian Institute of Sport Assessment Achilles (VISA-A). Relationships between VAS and VON, VISA-A and VON, VAS and VOAT, VISA-A and VOAT, VAS and VVI, and VISA-A and VVI, were statistically analyzed. The vascular mapping within and surrounding the symptomatic Achilles tendons was investigated. 97.3% of the Achilles tendons were found to have neovascularization. In 55.6% of these Achilles, the neovascularity was associated with the location of thickening. The VAS was found to be positively correlated with the VON and the VVI, the VON was found to be independent from the VOAT.


Assuntos
Tendão do Calcâneo/diagnóstico por imagem , Neovascularização Patológica/diagnóstico por imagem , Tendinopatia/diagnóstico por imagem , Ultrassonografia Doppler/métodos , Tendão do Calcâneo/irrigação sanguínea , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/complicações , Tamanho do Órgão , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tendinopatia/complicações
11.
Ultrasound Med Biol ; 37(7): 1046-55, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21640481

RESUMO

To investigate the amount of neovascularization in the symptomatic Achilles tendon, we developed a novel three-dimensional (3-D) power Doppler ultrasound scanning system to prospectively examine 10 patients with 12 symptomatic Achilles tendons, as well as 20 asymptomatic Achilles tendons as a control group. The mean volume of neovascularity (VON) in the whole Achilles tendon was calculated during the phase of the cardiac cycle displaying maximum vascularity and also during the phase of the cardiac cycle displaying the minimum. The mean VONs in the control group were found to be 0.41 mm(3) (maximum) and 0.02 mm(3) (minimum), respectively. The mean VONs in patients with painful Achilles tendon were 380 mm(3) (maximum) and 70.3 mm(3) (minimum), respectively. The initial results showed that the 3-D power Doppler ultrasound system could be used to measure the mean VON in controls and in patients with symptomatic Achilles tendinopathy. The results demonstrated a significantly greater VON in the maximum phase compared with the minimum phase as well as in the patient group compared with that in the control group. The system was therefore capable of defining the degree of vascularity in the Achilles tendon.


Assuntos
Tendão do Calcâneo/diagnóstico por imagem , Imageamento Tridimensional , Neovascularização Patológica/diagnóstico por imagem , Tendinopatia/diagnóstico por imagem , Ultrassonografia Doppler em Cores/métodos , Tendão do Calcâneo/lesões , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Estatísticas não Paramétricas
12.
J Orthop Res ; 27(11): 1457-60, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19396861

RESUMO

Kager's fat pad is located in Kager's triangle between the Achilles tendon, the superior cortex of the calcaneus, and flexor hallucis longus (FHL) muscle and tendon. Its biomechanical functions are not yet established, but recent studies suggest it performs important biomechanical roles as it is lined by a synovial membrane and its retrocalcaneal protruding wedge can be observed moving into the bursal space during ankle plantarflexion. Such features have prompted hypotheses that the protruding wedge assists in the lubrication of the Achilles tendon subtendinous area, distributes stress at the Achilles enthesis, and removes debris from within the retrocalcaneal bursa. This study examined the influence of FHL activity and Achilles tendon load on the protruding wedge sliding distance, using both dynamic ultrasound imaging and surface electromyogram. Intervolunteer results showed sliding distance was independent of FHL activity. This study has shown the protruding wedge to slide on average 60% further into the retrocalcaneal bursa when comparing the Achilles tendon loaded versus unloaded, consistently reaching the distal extremity. Sliding distance was dependent on a change in the Achilles tendon insertion angle. Our results support a number of hypothesized biomechanical functions of the protruding wedge including: lubrication of the subtendinous region; reduction of pressure change within the Achilles tendon enthesis organ; and removal of debris from within the retrocalcaneal bursa.


Assuntos
Tendão do Calcâneo/fisiologia , Tecido Adiposo/fisiologia , Articulação do Tornozelo/fisiologia , Movimento , Adulto , Fenômenos Biomecânicos , Calcâneo , Eletromiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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