Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 91
Filtrar
1.
Gait Posture ; 111: 185-190, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38718524

RESUMO

BACKGROUND: The linear-envelope peak (LEP) of surface EMG signal is widely used in gait analysis to characterize muscular activity, especially in clinics. RESEARCH QUESTION: This study is designed to evaluate LEP accuracy in identifying muscular activation and assessing activation timing during walking. METHODS: Surface EMG signals from gastrocnemius lateralis (GL) and tibialis anterior (TA) were analyzed in 100 strides per subject (31 healthy subjects) during ground walking. Signals were full-wave rectified and low-pass filtered (cut-off frequency=5 Hz) to extract the linear envelope. LEP accuracy in identifying muscle activations and the associated error in peak detection were assessed by direct comparison with a reference method based on wavelet transform. LEP accuracy in identifying the timing of higher signalenergy levels was also assessed, increasing the reference-algorithm selectivity. RESULTS: The detection error (percentage number of times when LEP falls outside the correspondent reference activation interval) is close to zero. Detection error increases up to 70% for intervals including only signal energy higher than 90% of energy peak. Mean absolute error (MAE, the absolute value of the distance between LEP timing and the correspondent actual timing of the sEMG-signal peak computed by reference algorithm) is 54.1±20.0 ms. Detection error and MAE are significantly higher (p<0.05) in TA data compared to GL signals. Differences among MAE values detected adopting different values for LE cut-off frequency are not statistically significant. SIGNIFICANCE: LEP was found to be accurate in identifying the number of muscle activations during walking. However, the use of LEP to assess the timing of highest sEMG-signal energy (signal peak) should be considered carefully. Indeed, it could introduce a relevant inaccuracy in muscle-activation identification and peak-timing quantification. The type of muscle to analyze could also influence LEP performances, while the cut-off frequency chosen for envelope extraction appears to have a limited impact.

2.
Sci Data ; 10(1): 650, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37739950

RESUMO

Globally, interactions between fishing activities and dolphins are cause for concern due to their negative effects on both mammals and fishermen. The recording of acoustic emissions could aid in detecting the presence of dolphins in close proximity to fishing gear, elucidating their behavior, and guiding potential management measures designed to limit this harmful phenomenon. This data descriptor presents a dataset of acoustic recordings (WAV files) collected during interactions between common bottlenose dolphins (Tursiops truncatus) and fishing activities in the Adriatic Sea. This dataset is distinguished by the high complexity of its repertoire, which includes various different typologies of dolphin emission. Specifically, a group of free-ranging dolphins was found to emit frequency-modulated whistles, echolocation clicks, and burst pulse signals, including feeding buzzes. An analysis of signal quality based on the signal-to-noise ratio was conducted to validate the dataset. The signal digital files and corresponding features make this dataset suitable for studying dolphin behavior in order to gain a deeper understanding of their communication and interaction with fishing gear (trawl).


Assuntos
Golfinho Nariz-de-Garrafa , Ecolocação , Animais , Som , Acústica , Frequência Cardíaca
3.
J Innov Card Rhythm Manag ; 14(4): 5410-5419, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37143577

RESUMO

Ultrasound-guided axillary vein access is an effective alternative to conventional subclavian and cephalic access for cardiac implantable electronic device implantation. The aim of this study was to compare the safety, efficacy, and radiation exposure data of the ultrasound-guided axillary approach with other conventional access techniques. The study population included 130 consecutive patients, stratified as 65 (64% male; median age, 79 years) in the study group and 65 (66% male; median age, 81 years) in the control group. We performed a retrospective not-randomized analysis by comparing ultrasound-guided axillary vein puncture with subclavian and cephalic approaches in order to test the effect on X-ray exposure, total procedure time, and complications. Significant differences were observed in terms of radiation exposure, including fluoroscopy time (median, 95 s [study group] vs. 193 s [control group]; P < .001), air kerma (median, 29 mGy [study group] vs. 55.7 mGy [control group]; P < .001), and dose-area product (median, 8219 mGy·cm2 [study group] vs. 16736 mGy·cm2 [control group]; P < .001). The median procedure time was 45 min in the study group but 50 min in the control group (P < .05). Complications occurred in 6 control group patients (1 urticaria contrast medium-related, 3 pneumothorax, 2 subclavian artery puncture) and 2 study group patients (2 axillary artery puncture). We conclude that the ultrasound-guided axillary venous approach is a fast, feasible, and safe technique for cardiac lead implantation. It allows a significant reduction in fluoroscopy time without prolonging the procedural time. This approach offers direct visualization of the vessel during the puncture, so it can be useful in patients who cannot receive contrast medium, those who require "difficult" thoracic approaches (emphysema, too much or too little fat tissue), or those on anticoagulant therapy.

4.
Artigo em Inglês | MEDLINE | ID: mdl-36293992

RESUMO

BACKGROUND: Almost half of antimicrobial prescriptions in long-term care facilities (LTCFs) is inappropriate. This broad use might represent a strong contributor to antimicrobial resistance in these facilities. This study aimed to assess antibiotic use patterns and potential associated factors with a survey of LTCFs in the local health authority (LHA) of Novara. METHODS: A cross-sectional study was conducted in 25 LTCFs in the LHA of Novara following the healthcare-associated infection in LCTFs (HALT) protocol. Information on residents and facilities was assessed. Antibiotic usage and potential determinants were also estimated. RESULTS: In total, 1137 patients were screened for antibiotic usage. Mean age was 84.58 years (SD 9.77), and the majority were female (76.52%). Twenty-six were antibiotic users (prevalence rate 2.29%, 95%CI 1.50-3.33). Antimicrobials were mainly prescribed orally (84.62%). Potential risk factors for antibiotic prescription were catheter use (central and peripheral venous, p-values 0.0475 and 0.0034, respectively, and urinary, p-value 0.0008), immobilization (p-value < 0.0001), and sex (p-value 0.0486). CONCLUSIONS: This study identified a low prevalence of antimicrobic consumption in LTCFs. Further surveillance studies are warranted to identify trends and changes in pathogen incidence and antimicrobial resistance and to inform public health authorities on the necessity of prudent use of antimicrobials in LCTFs.


Assuntos
Anti-Infecciosos , Uso de Medicamentos , Humanos , Feminino , Masculino , Idoso de 80 Anos ou mais , Assistência de Longa Duração , Prevalência , Estudos Transversais , Anti-Infecciosos/uso terapêutico , Antibacterianos/uso terapêutico , Itália/epidemiologia , Prescrição Inadequada
5.
Sensors (Basel) ; 22(13)2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35808382

RESUMO

BACKGROUND: Muscle co-contraction plays a significant role in motion control. Available detection methods typically only provide information in the time domain. The current investigation proposed a novel approach for muscle co-contraction detection in the time-frequency domain, based on continuous wavelet transform (CWT). METHODS: In the current study, the CWT-based cross-energy localization of two surface electromyographic (sEMG) signals in the time-frequency domain, i.e., the CWT coscalogram, was adopted for the first time to characterize muscular co-contraction activity. A CWT-based denoising procedure was applied for removing noise from the sEMG signals. Algorithm performances were checked on synthetic and real sEMG signals, stratified for signal-to-noise ratio (SNR), and then validated against an approach based on the acknowledged double-threshold statistical algorithm (DT). RESULTS: The CWT approach provided an accurate prediction of co-contraction timing in simulated and real datasets, minimally affected by SNR variability. The novel contribution consisted of providing the frequency values of each muscle co-contraction detected in the time domain, allowing us to reveal a wide variability in the frequency content between subjects and within stride. CONCLUSIONS: The CWT approach represents a relevant improvement over state-of-the-art approaches that provide only a numerical co-contraction index or, at best, dynamic information in the time domain. The robustness of the methodology and the physiological reliability of the experimental results support the suitability of this approach for clinical applications.


Assuntos
Contração Muscular , Músculo Esquelético , Algoritmos , Eletromiografia/métodos , Humanos , Contração Muscular/fisiologia , Músculo Esquelético/fisiologia , Reprodutibilidade dos Testes , Processamento de Sinais Assistido por Computador , Análise de Ondaletas
6.
Sensors (Basel) ; 22(9)2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35591084

RESUMO

BACKGROUND: Muscular-activity timing is useful information that is extractable from surface EMG signals (sEMG). However, a reference method is not available yet. The aim of this study is to investigate the reliability of a novel machine-learning-based approach (DEMANN) in detecting the onset/offset timing of muscle activation from sEMG signals. METHODS: A dataset of 2880 simulated sEMG signals, stratified for signal-to-noise ratio (SNR) and time support, was generated to train a hidden single-layer fully-connected neural network. DEMANN's performance was evaluated on simulated sEMG signals and two different datasets of real sEMG signals. DEMANN was validated against different reference algorithms, including the acknowledged double-threshold statistical algorithm (DT). RESULTS: DEMANN provided a reliable prediction of muscle onset/offset in simulated and real sEMG signals, being minimally affected by SNR variability. When directly compared with state-of-the-art algorithms, DEMANN introduced relevant improvements in prediction performances. CONCLUSIONS: These outcomes support DEMANN's reliability in assessing onset/offset events in different motor tasks and the condition of signal quality (different SNR), improving reference-algorithm performances. Unlike other works, DEMANN's adopts a machine learning approach where a neural network is trained by only simulated sEMG signals, avoiding the possible complications and costs associated with a typical experimental procedure, making this approach suitable to clinical practice.


Assuntos
Aprendizado de Máquina , Redes Neurais de Computação , Algoritmos , Eletromiografia/métodos , Reprodutibilidade dos Testes
7.
Sarcoidosis Vasc Diffuse Lung Dis ; 38(3): e2021017, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34744417

RESUMO

BACKGROUND: Granulomatous interstitial nephritis in sarcoidosis (sGIN) is generally clinically silent, but in <1% causes acute kidney injury (AKI). METHODS: This Italian multicentric retrospective study included 39 sarcoidosis-patients with renal involvement at renal biopsy: 31 sGIN-AKI, 5 with other patterns (No-sGIN-AKI), 3 with nephrotic proteinuria. We investigate the predictive value of clinical features, laboratory, radiological parameters and histological patterns regarding steroid response. Primary endpoint: incident chronic kidney disease (CKD) beyond the 1°follow-up (FU) year; secondary endpoint: response at 1°line steroid therapy; combined endpoint: the association of initial steroid response and outcome at the end of FU. RESULTS: Complete recovery in all 5 No-sGIN-AKI-patients, only in 45% (13/29) sGIN-AKI-patients (p=0.046) (one lost in follow-up, for another not available renal function after steroids). Nobody had not response. Primary endpoint of 22 sGIN-AKI subjects: 65% (13/20) starting with normal renal function developed CKD (2/22 had basal CKD; median FU 77 months, 15-300). Combined endpoint: 29% (6/21) had complete recovery and final normal renal function (one with renal relapse), 48% (10/21) had partial recovery and final CKD (3 with renal relapse, of whom one with basal CKD) (p=0.024). Acute onset and hypercalcaemia were associated to milder AKI and better recovery than subacute onset and patients without hypercalcaemia, women had better endpoints than men. Giant cells, severe interstitial infiltrate and interstitial fibrosis seemed negative predictors in terms of endpoints. CONCLUSIONS: sGIN-AKI-patients with no complete recovery at 1°line steroid should be treated with other immunosuppressive to avoid CKD, in particular if males with subacute onset and III stage-not hypercalcaemic AKI.

8.
Artigo em Inglês | MEDLINE | ID: mdl-33909568

RESUMO

Machine-learning techniques are suitably employed for gait-event prediction from only surface electromyographic (sEMG) signals in control subjects during walking. Nevertheless, a reference approach is not available in cerebral-palsy hemiplegic children, likely due to the large variability of foot-floor contacts. This study is designed to investigate a machine-learning-based approach, specifically developed to binary classify gait events and to predict heel-strike (HS) and toe-off (TO) timing from sEMG signals in hemiplegic-child walking. To this objective, sEMG signals are acquired from five hemiplegic-leg muscles in nearly 2500 strides from 20 hemiplegic children, acknowledged as Winters' group 1 and 2. sEMG signals, segmented in overlapping windows of 600 samples (pace = 5 samples), are used to train a multi-layer perceptron model. Intra-subject and inter-subject experimental settings are tested. The best-performing intra-subject approach is able to provide in the hemiplegic population a mean classification accuracy (±SD) of 0.97±0.01 and a suitable prediction of HS and TO events, in terms of average mean absolute error (MAE, 14.8±3.2 ms for HS and 17.6±4.2 ms for TO) and F1-score (0.95±0.03 for HS and 0.92±0.07 for TO). These results outperform previous sEMG-based attempts in cerebral-palsy populations and are comparable with outcomes achieved by reference approaches in control populations. In conclusion, the findings of the study prove the feasibility of neural networks in predicting the two main gait events using surface EMG signals, also in condition of high variability of the signal to predict as in hemiplegic cerebral palsy.


Assuntos
Paralisia Cerebral , Paralisia Cerebral/complicações , Paralisia Cerebral/diagnóstico , Criança , Eletromiografia , Marcha , Humanos , Aprendizado de Máquina , Caminhada
9.
Biomed Eng Online ; 19(1): 58, 2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32723335

RESUMO

BACKGROUND: Machine learning models were satisfactorily implemented for estimating gait events from surface electromyographic (sEMG) signals during walking. Most of them are based on inter-subject approaches for data preparation. Aim of the study is to propose an intra-subject approach for binary classifying gait phases and predicting gait events based on neural network interpretation of sEMG signals and to test the hypothesis that the intra-subject approach is able to achieve better performances compared to an inter-subject one. To this aim, sEMG signals were acquired from 10 leg muscles in about 10.000 strides from 23 healthy adults, during ground walking, and a multi-layer perceptron (MLP) architecture was implemented. RESULTS: Classification/prediction accuracy was tested vs. the ground truth, represented by the foot-floor-contact signal provided by three foot-switches, through samples not used during training phase. Average classification accuracy of 96.1 ± 1.9% and mean absolute value (MAE) of 14.4 ± 4.7 ms and 23.7 ± 11.3 ms in predicting heel-strike (HS) and toe-off (TO) timing were provided. Performances of the proposed approach were tested by a direct comparison with performances provided by the inter-subject approach in the same population. Comparison results showed 1.4% improvement of mean classification accuracy and a significant (p < 0.05) decrease of MAE in predicting HS and TO timing (23% and 33% reduction, respectively). CONCLUSIONS: The study developed an accurate methodology for classification and prediction of gait events, based on neural network interpretation of intra-subject sEMG data, able to outperform more typical inter-subject approaches. The clinically useful contribution consists in predicting gait events from only EMG signals from a single subject, contributing to remove the need of further sensors for the direct measurement of temporal data.


Assuntos
Eletromiografia , Análise da Marcha , Redes Neurais de Computação , Processamento de Sinais Assistido por Computador , Adulto , Feminino , Humanos , Masculino
10.
Biosensors (Basel) ; 9(3)2019 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-31252517

RESUMO

Hemiplegia is a neurological disorder that is often detected in children with cerebral palsy. Although many studies have investigated muscular activity in hemiplegic legs, few EMG-based findings focused on unaffected limb. This study aimed to quantify the asymmetric behavior of lower-limb-muscle recruitment during walking in mild-hemiplegic children from surface-EMG and foot-floor contact features. sEMG signals from tibialis anterior (TA) and gastrocnemius lateralis and foot-floor contact data during walking were analyzed in 16 hemiplegic children classified as W1 according to Winter' scale, and in 100 control children. Statistical gait analysis, a methodology achieving a statistical characterization of gait by averaging surface-EMG-based features, was performed. Results, achieved in hundreds of strides for each child, indicated that in the hemiplegic side with respect to the non-hemiplegic side, W1 children showed a statistically significant: decreased number of strides with normal foot-floor contact; decreased stance-phase length and initial-contact sub-phase; curtailed, less frequent TA activity in terminal swing and a lack of TA activity at heel-strike. The acknowledged impairment of anti-phase eccentric control of dorsiflexors was confirmed in the hemiplegic side, but not in the contralateral side. However, a modified foot-floor contact pattern is evinced also in the contralateral side, probably to make up for balance requirements.


Assuntos
Paralisia Cerebral/diagnóstico , Paralisia Cerebral/fisiopatologia , Eletromiografia , Marcha , Hemiplegia/diagnóstico , Hemiplegia/fisiopatologia , Caminhada , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Eletromiografia/métodos , Feminino , Humanos , Masculino , Músculo Esquelético/fisiopatologia , Estudos Retrospectivos , Índice de Gravidade de Doença , Avaliação de Sintomas
11.
J Opioid Manag ; 15(1): 43-49, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30855722

RESUMO

OBJECTIVES: An adequate perioperative analgesia reduces neuroendocrine stress response and postoperative complica-tions. Opioids are the most effective parenteral drugs to control pain and stress response. DESIGN: This is a prospective randomized double-blinded controlled study. SETTING: Institutional tertiary level. PATIENTS, PARTICIPANTS: Fifty patients underwent general anesthesia with desflurane for laparoscopic cholecystectomy. MAIN OUTCOME MEASURES: To compare two different doses of remifentanil (0.15 mcg/kg/min or 0.3 mcg/kg/min) in reducing markers of stress. Perioperative stress was assessed through the dosage of adrenocorticotropic hormone (ACTH), cortisol, growth hormone (GH), and prolactin (PRL). Three venous blood samples were collected from patients: before transferring the patient to the operating room (Time 0), at the trocar insertion (Time 1), and 1 hour after the end of the surgery (Time 2). RESULTS: Hemodynamic parameters showed no differences between the two groups. The authors observed an increase of GH and PRL in both groups at trocar insertion (Time 1) (p = 0.473 and 0.754, respectively). ACTH and cortisol showed a decrease at Time 1 and an increase after surgery (p = 0.586). The modification of stress parameters levels showed no significant differences between the two groups. CONCLUSIONS: The results of our study showed that a lower dose of remifentanil is equally effective in controlling stress hormones during laparoscopic cholecystectomy.


Assuntos
Analgésicos Opioides/uso terapêutico , Colecistectomia Laparoscópica , Remifentanil/uso terapêutico , Estresse Fisiológico/efeitos dos fármacos , Colecistectomia Laparoscópica/efeitos adversos , Relação Dose-Resposta a Droga , Hormônios/sangue , Humanos , Estudos Prospectivos
12.
Eur J Clin Invest ; 49(6): e13099, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30838644

RESUMO

BACKGROUND: Obesity is known to induce a deterioration of insulin sensitivity (SI ), one of the insulin-dependent components of glucose tolerance. However, few studies investigated whether obesity affects also the insulin-independent component, that is glucose effectiveness (SG ). This cross-sectional study aimed to analyse SG and its components in different body mass index (BMI) categories. MATERIALS AND METHODS: Three groups of subjects spanning different BMI (kg m-2 ) categories underwent a 3-h frequently sampled intravenous glucose tolerance test: Lean (LE; 18.5 ≤ BMI < 25, n = 73), Overweight (OW; 25 ≤ BMI < 30, n = 90), and Obese (OB; BMI ≥ 30, n = 41). OB has been further divided into two subgroups, namely Obese I (OB-I; 30 ≤ BMI < 35, n = 27) and Morbidly Obese (OB-M; BMI ≥ 35, n = 14). Minimal model analysis provided SG and its components at zero (GEZI) and at basal (BIE) insulin. RESULTS: Values for SG were 1.98 ± 1.30 × 10-2 ·min-1 in all subjects grouped and 2.38 ± 1.23, 1.84 ± 0.82, 1.59 ± 0.61 10-2 ·min-1 in LE, OW and OB, respectively. In all subjects grouped, a significant inverse linear correlation was found between the log-transformed values of SG and BMI (r = -0.3, P < 0.0001). SG was significantly reduced in OW and OB with respect to LE (P < 0.001) but no significant difference was detected between OB and OW (P = 0.35) and between OB-I and OB-M (P = 0.25). Similar results were found for GEZI. BIE was not significantly different among NW, OW and OB (P = 0.11) and between OB-I and OB-M (P ≥ 0.07). CONCLUSIONS: SG and its major component GEZI deteriorate in overweight individuals compared to those in the normal BMI range, without further deterioration when BMI increases above 30 kg m-2 .

13.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 3159-3162, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31946558

RESUMO

Knee osteoarthritis is commonly treated through total knee arthroplasty (TKA) or unicompartmental knee arthroplasty (UKA) and therefore the assessment of postoperative differences in functional capabilities between TKA and UKA patients appears of primary importance. Throughout the years, fractal analysis has been applied to several biological time-series, revealing to be particularly useful for assessing human balance and motor control by quantifying complexity and repeatability of dynamic measures. In this study, fractal dimension (FD) has been computed on ground reaction force and momentum acquired during squatting movement in two groups of TKA and UKA patients and a control group of healthy subjects (CTRL). FD resulted able to discriminate between TKA and both CTRL and UKA group, showing significant differences in all the considered measures. Outcomes of this study could help to gain further information about functional recovery after different knee arthroplasty procedures, in order to improve the choice of rehabilitative treatment.


Assuntos
Artroplastia do Joelho , Fractais , Osteoartrite do Joelho , Humanos , Articulação do Joelho , Osteoartrite do Joelho/fisiopatologia , Osteoartrite do Joelho/cirurgia , Recuperação de Função Fisiológica , Resultado do Tratamento
14.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 1213-1216, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31946111

RESUMO

Inertial measurement units are an efficient tool to estimate the orientation of a rigid body with respect to a global or navigation frame. Thanks to their relatively small scale, these devices are often employed in clinical environments in form of wearable devices. A direct consequence of this large use of inertial sensors has been the development of many sensor fusion techniques for pose estimation in many practical applications. In this paper we study the feasibility of a nonlinear "Unscented" variant of the well-known Kalman Filter for gyroscope/accelerometer sensor fusion in pelvis pose estimation during treadmill walking. In addition, orientation estimation has been obtained without IMU magnetometer data, in order to propose a method suitable also for environments where magnetic disturbances could arise. Pelvis heading (yaw), bank (roll) and attitude (pitch) angles have been evaluated both using the proposed filter and a gold standard optometric system. The root mean square errors obtained using the proposed sensor fusion with respect to the gold standard are below 1 degree for each axis, showing also a significant high correlation (> 0.90). Findings of this study highlight the suitability of a magnetometer-free UKF approach for pose estimation of pelvis during human walking on treadmill, providing information useful also for further estimation of center of mass displacement in the same experimental conditions.


Assuntos
Acelerometria , Algoritmos , Caminhada , Acelerometria/instrumentação , Humanos , Pelve
15.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 5335-5338, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31947061

RESUMO

Upright stance maintenance under perturbed condition is a complex phenomenon in which the Central Nervous System(CNS) is engaged to regulate the balance preventing subject to fall. Many models of unperturbed stance are present in literature. However, the necessity to model balance maintenance in presence of external disturbance is still an open problem. In this paper, a new model representing the human balance maintenance under perturbed condition is presented. An adaptive sliding mode approach is used to model the action played by the CNS, the control parameters are then optimized in order to match real and simulated data. The trend of optimized parameters seems to reveal the development of different postural strategies throughout the experimental trials.


Assuntos
Sistema Nervoso Central/fisiologia , Modelos Biológicos , Equilíbrio Postural , Postura , Humanos
16.
J Electromyogr Kinesiol ; 42: 117-122, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30025300

RESUMO

Muscular co-activation is a well-known mechanism for lower limb joint stabilization in both healthy and pathological individuals. This muscular feature appears particularly important for the knee joint, not only during challenging motor tasks such as cutting and landing but also during walking, due to knee cyclic loading. Gastrocnemius acts on the knee joint with a flexor activity and co-activations with quadriceps muscles lead to greater knee ligament strain with respect to an isolated burst of either muscle. Thus, this study aimed to assess possible co-activations between gastrocnemius and quadriceps muscles during walking. Five co-activation periods were assessed: during early stance (identified in 5.7 ±â€¯5.1% of total strides), early and late foot-contact (88.9 ±â€¯8.9% and 8.9 ±â€¯8.2%), push-off (23.9 ±â€¯12.2%) and late swing (29.0 ±â€¯16.1%). Outcomes showed that late foot-contact and swing co-activations could deserve particular attention: in both cases the knee joint was close to the full extension (around 3.5° and 6°, respectively) and thus, considering also the anterior tibia translation due to the quadriceps activity, the simultaneous gastrocnemius burst could lead to an enhanced knee ligaments elongation. Findings of this study represent the first attempt to provide a reference knee joint co-activation framework, useful also for further evaluation in cohorts with knee failures.


Assuntos
Contração Isométrica , Articulação do Joelho/fisiologia , Músculo Esquelético/fisiologia , Caminhada , Adulto , Feminino , Humanos , Joelho/fisiologia , Masculino
17.
IEEE Trans Neural Syst Rehabil Eng ; 26(7): 1400-1406, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29985149

RESUMO

The functional reach test (FRT) is widely used for assessing dynamic balance stability in elderly and pathological subjects. Force platforms (FPs) represent a fundamental part of the instrumented FRT experimental setup due to the central role of center-of-pressure (COP) displacement in FRT analysis. Recently, the nintendo wii balance board (NBB) has been suggested as a low-cost and reliable device for ground reaction force and COP measurement in poorly dynamic motor tasks. Therefore, this paper aimed to compare NBB-COP data with those obtained from a laboratory-grade platform during FRT. Data from 48 healthy subjects were simultaneously acquired from both devices. FP-COP and NBB-COP trajectories showed a remarkable correlation in both directions ( ) and low root-mean-square error values (1.14 ± 0.88 mm and 0.55 ± 0.28 mm for anterior-posterior and medial-lateral direction). Fixed biases between COP-based parameters did not exceed 2% of the FP outcomes with high consistency throughout the present measurement range (ICC consistency always >0.950). Only the COP mean velocity exhibited a tendency toward proportional errors, which can be adjusted by a calibration of NBB data. Findings of this paper confirmed the NBB validity for COP measurement in a widely used motor task as the functional reach, supporting the feasibility of NBB in research scenarios.


Assuntos
Equilíbrio Postural/fisiologia , Desempenho Psicomotor/fisiologia , Adulto , Fenômenos Biomecânicos , Calibragem , Feminino , Voluntários Saudáveis , Humanos , Masculino , Modalidades de Fisioterapia , Padrões de Referência , Jogos de Vídeo , Adulto Jovem
18.
Acta Diabetol ; 55(10): 1011-1018, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29931422

RESUMO

AIMS: Minimal model analysis of intravenous glucose tolerance test (IVGTT) data represents the reference method to assess insulin sensitivity (SI) and glucose effectiveness (SG) that quantify the insulin-dependent and insulin-independent processes of glucose disappearance, respectively. However, test duration (3 h) and need for modeling expertise limit the applicability of this method. Aim of this study was providing a simple predictor of SG applicable to short test (1 h), as previously done with SI. METHODS: Three groups of subjects reflecting different glucose tolerance degrees underwent a 3 h IVGTT: subjects with normal glucose tolerance (NGT, n = 164), with defective glucose regulation (DGR, n = 191), and with type 2 diabetes (T2D, n = 39). Minimal model analysis provided reference SG and its components at zero (GEZI) and basal (BIE) insulin. The simple predictor CSG (calculated SG) was described by the formula CSG = α0 + α1 × KG/Gpeak, being KG the glucose disappearance rate (between 10 and 50 min) and Gpeak the maximum of the glucose curve during the test; α0 and α1 coefficients were provided by linear regression analysis. RESULTS: CSG and SG showed a markedly significant relationship in the whole dataset (r = 0.72, p < 0.0001) and in the single groups (r = 0.70 in NGT, r = 0.71 in DGR and r = 0.70 in T2D, p < 0.0001 for all); α1 × KG/Gpeak was significantly related to GEZI (r ≥ 0.60). CONCLUSIONS: The interest for insulin-independent glucose disappearance is increasing, due to the recent availability of SGLT2 pharmacological agents, lowering glycemic levels without requiring insulin action. This study proposes a reliable predictor of SG based on IVGTT lasting 1 h only, and not requiring mathematical modeling skills.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Teste de Tolerância a Glucose , Adulto , Idoso , Feminino , Humanos , Insulina/metabolismo , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Adulto Jovem
19.
Biomed Res Int ; 2018: 1868254, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29713640

RESUMO

The use of anaesthetic drugs in the treatment of oral aphthosis is one of the pharmaceutical possibilities that a doctor can use for the most painful forms. Normally, Lidocaine or Diclofenac is used to treat this disease, but they can be used for a very limited time and so they are of little practical use. In this study, the authors have used Ropivacaine whose pharmaceutical kinetics allows the analgesic effect to be active for 60 to 90 minutes. In our research, we compared 8 groups of patients who have been given 3 principal pharmaceutical products: one group was given an anaesthetic drug, one had a topical medication administered which is often used for the treatment of aphthous lesions, and the last group was given a multivitamin. These pharmaceutical products were used alone and in various possible combinations in the 8 groups. The results of this study are very interesting and show that in all the groups that used anaesthetics there was more satisfaction on the patients' part because their pain level became more manageable right after the first application of the drug and the patients could carry on with their normal lives.


Assuntos
Amidas/administração & dosagem , Anestésicos Locais/administração & dosagem , Estomatite Aftosa/tratamento farmacológico , Adulto , Amidas/efeitos adversos , Anestésicos Locais/efeitos adversos , Feminino , Humanos , Masculino , Ropivacaina
20.
Comput Methods Programs Biomed ; 156: 133-139, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29428065

RESUMO

BACKGROUND AND OBJECTIVE: Cardiotocography (CTG), consisting in the simultaneous recording of fetal heart rate (FHR) and maternal uterine contractions (UC), is a popular clinical test to assess fetal health status. Typically, CTG machines provide paper reports that are visually interpreted by clinicians. Consequently, visual CTG interpretation depends on clinician's experience and has a poor reproducibility. The lack of databases containing digital CTG signals has limited number and importance of retrospective studies finalized to set up procedures for automatic CTG analysis that could contrast visual CTG interpretation subjectivity. In order to help overcoming this problem, this study proposes an electronic procedure, termed eCTG, to extract digital CTG signals from digital CTG images, possibly obtainable by scanning paper CTG reports. METHODS: eCTG was specifically designed to extract digital CTG signals from digital CTG images. It includes four main steps: pre-processing, Otsu's global thresholding, signal extraction and signal calibration. Its validation was performed by means of the "CTU-UHB Intrapartum Cardiotocography Database" by Physionet, that contains digital signals of 552 CTG recordings. Using MATLAB, each signal was plotted and saved as a digital image that was then submitted to eCTG. Digital CTG signals extracted by eCTG were eventually compared to corresponding signals directly available in the database. Comparison occurred in terms of signal similarity (evaluated by the correlation coefficient ρ, and the mean signal error MSE) and clinical features (including FHR baseline and variability; number, amplitude and duration of tachycardia, bradycardia, acceleration and deceleration episodes; number of early, variable, late and prolonged decelerations; and UC number, amplitude, duration and period). RESULTS: The value of ρ between eCTG and reference signals was 0.85 (P < 10-560) for FHR and 0.97 (P < 10-560) for UC. On average, MSE value was 0.00 for both FHR and UC. No CTG feature was found significantly different when measured in eCTG vs. reference signals. CONCLUSIONS: eCTG procedure is a promising useful tool to accurately extract digital FHR and UC signals from digital CTG images.


Assuntos
Cardiotocografia/métodos , Processamento Eletrônico de Dados , Frequência Cardíaca Fetal/fisiologia , Processamento de Sinais Assistido por Computador , Contração Uterina , Bradicardia , Calibragem , Bases de Dados Factuais , Feminino , Humanos , Gravidez , Valores de Referência , Reprodutibilidade dos Testes , Software , Taquicardia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA