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1.
Sensors (Basel) ; 22(7)2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35408063

RESUMO

Complications related to neuromuscular blockade (NMB) could occur during anesthesia induction, maintenance, and emergency. It is recommended that neuromuscular monitoring techniques be utilized perioperatively to avoid adverse outcomes. However, current neuromuscular monitoring methods possess different shortcomings. They are cumbersome to use, susceptible to disturbances, and have limited alternative monitoring sites. Phonomyography (PMG) monitoring based on the acoustic signals yielded by skeletal muscle contraction is emerging as an interesting and innovative method. This technique is characterized by its convenience, stable signal quality, and multimuscle recording ability and shows great potential in the application field. This review summarizes the progression of PMG on perioperative neuromuscular monitoring chronologically and presents the merits, demerits, and challenges of PMG-based equipment, aiming at underscoring the potential of PMG-based apparatuses for neuromuscular monitoring.


Assuntos
Miografia , Bloqueio Neuromuscular , Estimulação Elétrica , Contração Muscular/fisiologia , Miografia/métodos , Bloqueio Neuromuscular/métodos , Monitoração Neuromuscular
2.
Sensors (Basel) ; 22(8)2022 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-35459072

RESUMO

Sarcopenia is a wild chronic disease among elderly people. Although it does not entail a life-threatening risk, it will increase the adverse risk due to the associated unsteady gait, fall, fractures, and functional disability. The import factors in diagnosing sarcopenia are muscle mass and strength. The examination of muscle mass must be carried in the clinic. However, the loss of muscle mass can be improved by rehabilitation that can be performed in non-medical environments. Electronic impedance myography (EIM) can measure some parameters of muscles that have the correlations with muscle mass and strength. The goal of this study is to use machine learning algorithms to estimate the total mass of thigh muscles (MoTM) with the parameters of EIM and body information. We explored the seven major muscles of lower limbs. The feature selection methods, including recursive feature elimination (RFE) and feature combination, were used to select the optimal features based on the ridge regression (RR) and support vector regression (SVR) models. The optimal features were the resistance of rectus femoris normalized by the thigh circumference, phase of tibialis anterior combined with the gender, and body information, height, and weight. There were 96 subjects involved in this study. The performances of estimating the MoTM used the regression coefficient (r2) and root-mean-square error (RMSE), which were 0.800 and 0.929, and 1.432 kg and 0.980 kg for RR and SVR models, respectively. Thus, the proposed method could have the potential to support people examining their muscle mass in non-medical environments.


Assuntos
Sarcopenia , Idoso , Algoritmos , Impedância Elétrica , Humanos , Aprendizado de Máquina , Músculo Esquelético/fisiologia , Miografia/métodos , Sarcopenia/diagnóstico
3.
Microcirculation ; 29(3): e12756, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35289024

RESUMO

OBJECTIVE: The myogenic response sets the foundation for blood flow control. Recent findings suggest a role for G protein-coupled receptors (GPCR) and signaling pathways tied to the generation of reactive oxygen species (ROS). In this regard, this study ascertained the impact of NADPH oxidase (Nox) on myogenic tone in rat cerebral resistance arteries. METHODS: The study employed real-time qPCR (RT-qPCR), pressure myography, and immunohistochemistry. RESULTS: Gq blockade abolished myogenic tone in rat cerebral arteries, linking GPCR to mechanosensation. Subsequent work revealed that general (TEMPOL) and mitochondrial specific (MitoTEMPO) ROS scavengers had little impact on myogenic tone, whereas apocynin, a broad spectrum Nox inhibitor, initiated transient dilation. RT-qPCR revealed Nox1 and Nox2 mRNA expression in smooth muscle cells. Pressure myography defined Nox1 rather than Nox2 is facilitating myogenic tone. We rationalized that Nox1-generated ROS was initiating this response by impairing the ability of the CaV 3.2 channel to elicit negative feedback via BKCa . This hypothesis was confirmed in functional experiments. The proximity ligation assay further revealed that Nox1 and CaV 3.2 colocalize within 40 nm of one another. CONCLUSIONS: Our data highlight that vascular pressurization augments Nox1 activity and ensuing ROS production facilitates myogenic tone by limiting Ca2+ influx via CaV 3.2.


Assuntos
Músculo Liso Vascular , NADPH Oxidases , Animais , Artérias Cerebrais/metabolismo , Músculo Liso Vascular/fisiologia , Miografia , Ratos , Espécies Reativas de Oxigênio/metabolismo
4.
Methods Mol Biol ; 2419: 361-376, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35237977

RESUMO

Wire myography enables the investigation of vascular tone and function of small vessels. The vessel of interest is harvested from the experimental model of choice, and then mounted as ring preparations onto a four-channel wire myograph. This technique enables ex vivo measurements of isometric response of vessels to different pharmacological agents. Here we describe in detail how to dissect, mount, and normalize vessels for the wire myography technique. We will also provide examples of how to construct concentration-response curves to a contractile and vasodilatory pharmacological agent.


Assuntos
Miografia , Vasodilatação , Artérias Mesentéricas/fisiologia , Contração Muscular , Músculo Liso Vascular/fisiologia , Miografia/métodos
5.
Viruses ; 14(2)2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35215989

RESUMO

It has been established that blood vessels are a target for influenza virus; however, the mechanism by which virus affects the cardiovascular system remains unknown. The aim of the study is the identification of histological changes and changes in the functional activity of the pulmonary and mesenteric blood vessels of Wistar rats. Wistar rats were intranasally infected with the influenza A(H1N1)pdm09 virus. At 24 and 96 h post infection (hpi), histopathological changes were observed in lung tissues with the absence of histological changes in mesenteric tissues. The functional activity of pulmonary and mesenteric arteries was determined using wire myography. In pulmonary arteries, there was a tendency towards an increase in integral response to the vasodilator and a decrease in the integral response to the vasoconstrictor at 24 hpi (compared with control). At 96 hpi, a tendency towards a decrease in the integral response to the vasoconstrictor persisted, while the response to acetylcholine was slightly increased. The functional activity of the mesenteric blood vessels was inverted: a significant decrease in the integral response to the vasodilator and an increase in the response to the vasoconstrictor at 24 hpi were observed; at 96 hpi, the integral response to the vasoconstrictor persisted, while the response to the vasodilator remained significantly reduced. Obtained data indicate the development of endothelial dysfunction in non-lethal and clinically non-severe experimental influenza virus infection.


Assuntos
Vírus da Influenza A Subtipo H1N1/imunologia , Pulmão/patologia , Artérias Mesentéricas/patologia , Infecções por Orthomyxoviridae/patologia , Células Epiteliais Alveolares/virologia , Animais , Imuno-Histoquímica , Pulmão/virologia , Masculino , Artérias Mesentéricas/virologia , Miografia , Infecções por Orthomyxoviridae/complicações , Infecções por Orthomyxoviridae/virologia , Ratos , Ratos Wistar
6.
PLoS One ; 17(1): e0262156, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34990494

RESUMO

Tensiomyography measures the radial displacement of a muscle during an electrically evoked twitch contraction. The rate of muscle displacement is increasingly reported to assess contractile properties. Several formulas currently exist to calculate the rate of displacement during the contraction phase of the maximal twitch response. However, information on the reproducibility of these formulas is scarce. Further, different rest intervals ranging from 10 s to 30 s are applied between consecutive stimuli during progressive electrical stimulation until the maximum twitch response. The effect of different rest intervals on the rate of displacement has not been investigated so far. The first aim of this study is to investigate the within and between-day reliability of the most frequently used formulas to calculate the rate of displacement. The second aim is to investigate the effect of changing the inter-stimulus interval on the rate of displacement. We will determine the rectus femoris and biceps femoris rate of displacement of twenty-four healthy subjects' dominant leg on two consecutive days. The maximum displacement curve will be determined two times within three minutes on the first day and a third time 24 h later. On day two, we will also apply three blocks of ten consecutive stimuli at a constant intensity of 50 mA. Inter-stimuli intervals will be 10 s, 20 s or 30 s in each block, respectively, and three minutes between blocks. The order of inter-stimulus intervals will be randomized. This study will allow a direct comparison between the five most frequently used formulas to calculate the rate of displacement in terms of their reproducibility. Our data will also inform on the effect of different inter-stimulus intervals on the rate of displacement. These results will provide helpful information on methodical considerations to determine the rate of displacement and may thus contribute to a standardized approach.


Assuntos
Joelho/fisiologia , Contração Muscular/fisiologia , Miografia , Adolescente , Adulto , Estimulação Elétrica , Feminino , Humanos , Masculino , Adulto Jovem
7.
IEEE Trans Biomed Eng ; 69(1): 244-255, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34161236

RESUMO

OBJECTIVE: Electrical impedance myography (EIM) measures bioimpedance over muscles. This paper proposes a circuit-based modelling methodology originated from finite element analysis (FEA), to emulate tissues and effects from anthropometric variations, and electrode placements, on EIM measurements. The proposed methodology is demonstrated on the upper arms and lower legs. METHODS: FEA evaluates impedance spectra (Z-parameters), sensitivity, and volume impedance density for variations of subcutaneous fat thickness (t f), muscle thickness (t m), and inter-electrode distance (IED), on limb models over 1Hz-1 MHz frequency range. The limbs' models are based on simplified anatomical data and dielectric properties from published sources. Contributions of tissues to the total impedance are computed from impedance sensitivity and density. FEA Z-parameters are imported into a circuit design environment, and used to develop a three Cole dispersion circuit-based model. FEA and circuit model simulation results are compared with measurements on ten human subjects. RESULTS: Muscle contributions are maximized at 31.25 kHz and 62.5 kHz for the upper arm and lower leg, respectively, at 4 cm IED. The circuit model emulates variations in t f and t m, and simulates up to 89 times faster than FEA. The circuit model matches subjects measurements with RMS errors and , while FEA does with and . CONCLUSIONS: We demonstrate that FEA is able to estimate the optimal frequencies and electrode placements, and circuit-based modelling can accurately emulate the limbs' bioimpedance. SIGNIFICANCE: The proposed methodology facilitates studying the impact of biophysical principles on EIM, enabling the development of future EIM acquisition systems.


Assuntos
Músculo Esquelético , Miografia , Braço , Impedância Elétrica , Análise de Elementos Finitos , Humanos
8.
Sci Rep ; 11(1): 23449, 2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-34873221

RESUMO

The purpose of the study was to compare sex adaptations in hypertrophy, strength and contractile properties of upper and lower-body muscles induced by resistance training (RT). Eighteen RT untrained male (MG) and female (FG) students (aged 24.1 ± 1.7 years, height: 1.75 ± 0.08 m, weight: 70.4 ± 12.3 kg) undervent 7 weeks of biceps curl and squat training (2 days/week, 60-70% repetition maximum, 3-4 sets, 120 s rest intervals, reps until muscular failure). At baseline and final measurement, thickness and cross-section area, one-repetition maximum and tensiomyography parameters (contraction time - Tc and radial displacement - Dm) of elbow flexors (biceps brachii) and knee extensors (4 quadriceps muscles) were evaluated. Although MG tends to display greater absolute strength gains for upper- (p = 0.055) and lower-body (p = 0.098), for relative changes ANCOVA revealed no sex-specific differences for either of the tested variables. Significant hypertrophy was observed for all tested muscles, except for vastus intermedius in FG (p = 0.076). The Dm significantly decreased for biceps brachii (MG by 12%, p < 0.01 and FG by 13.1%, p < 0.01) and rectus femoris (MG by19.2%, p < 0.01 and FG by 12.3%, p < 0.05), while Tc values remain unchanged. These results indicate that initial morphological, functional and contractile alterations following RT are similar for males and females, and that there are no specific sex adaptations either for the upper- or lower-body muscles. The study was registered with ClinicalTrials.gov (NCT04845295).


Assuntos
Músculo Esquelético/fisiologia , Treinamento de Força/métodos , Adaptação Fisiológica/fisiologia , Adulto , Cotovelo , Exercício Físico , Feminino , Humanos , Hipertrofia , Joelho , Masculino , Contração Muscular/fisiologia , Força Muscular/fisiologia , Miografia , Reprodutibilidade dos Testes , Fatores Sexuais , Adulto Jovem
9.
Physiol Rep ; 9(23): e15133, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34851043

RESUMO

The vasoconstrictive effect of sympathetic activity is attenuated in contracting skeletal muscle (functional sympatholysis), allowing increased blood supply to the working muscle but the underlying mechanisms are incompletely understood. The purpose of this study was to examine α-adrenergic receptor responsiveness in isolated artery segments from non-exercised and exercised mice, using wire myography. Isometric tension recordings performed on femoral artery segments from exercised mice showed decreased α-adrenergic receptor responsiveness compared to non-exercised mice (logEC50 -5.2 ± 0.04 M vs. -5.7 ± 0.08 M, respectively). In contrast, mesenteric artery segments from exercised mice displayed similar α-adrenergic receptor responses compared to non-exercised mice. Responses to the vasoconstrictor serotonin (5-HT) and vasodilator isoprenaline, were similar in femoral artery segments from non-exercised and exercised mice. To study sarcoplasmic reticulum (SR) function, we examined arterial contractions induced by caffeine, which depletes SR Ca2+ and thapsigargin, which inhibits SR Ca2+ -ATPase (SERCA) and SR Ca2+ uptake. Arterial contractions to both caffeine and thapsigargin were increased in femoral artery segment from exercised compared to non-exercised mice. Furthermore, 3D electron microscopy imaging of the arterial wall showed SR volume/length ratio increased 157% in smooth muscle cells of the femoral artery from the exercised mice, whereas there was no difference in SR volume/length ratio in mesenteric artery segments. These results show that in arteries surrounding exercising muscle, the α-adrenergic receptor constrictions are blunted, which can be attributed to swollen smooth muscle cell SR's, likely due to increased Ca2+ content that is possibly reducing free intracellular Ca2+ available for contraction. Overall, this study uncovers a previously unknown mechanism underlying functional sympatholysis.


Assuntos
Artérias Mesentéricas/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Condicionamento Físico Animal/fisiologia , Retículo Sarcoplasmático/efeitos dos fármacos , Animais , Cafeína/farmacologia , Cálcio/metabolismo , Artérias Mesentéricas/metabolismo , Camundongos , Contração Muscular/efeitos dos fármacos , Contração Muscular/fisiologia , Músculo Esquelético/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Miografia , Retículo Sarcoplasmático/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Simpatolíticos/farmacologia , Vasoconstritores/farmacologia
10.
Parkinsonism Relat Disord ; 93: 74-76, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34826764

RESUMO

The clinical benefit of Deep Brain Stimulation (DBS) is associated with electrode positioning accuracy. Intraoperative assessment of clinical effect is therefore key. Evaluating this clinical effect in patients with dystonic head tremor, as opposed to limb tremor, is challenging because the head is fixed in a stereotactic frame. To clinically assess head tremor during surgery, surface electromyography (EMG) electrodes were bilaterally applied to the sternocleidomastoid and cervical paraspinal muscles. This case shows that intraoperative polymyography is an easy and useful tool to assess the clinical effect of DBS electrode positioning.


Assuntos
Estimulação Encefálica Profunda/métodos , Distonia/cirurgia , Monitorização Neurofisiológica Intraoperatória/métodos , Miografia/métodos , Tremor/cirurgia , Idoso de 80 Anos ou mais , Feminino , Humanos , Ilustração Médica , Miografia/tendências
11.
J Healthc Eng ; 2021: 7296322, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34765103

RESUMO

The objective of this study was to evaluate the interrater and intrarater reliability of electrical impedance myography (EIM) using handheld sensors of different sizes. Electrical impedance myography of the biceps brachii muscle of twenty healthy individuals was performed by two raters using both large and small sensors. The procedures were also repeated 5 to 8 days after the first recording session. The repeatability of the resistance, reactance, and phase angle at two different current frequencies (50 and 100 kHz) was assessed by the intraclass correlation coefficient (ICC). The ICCs of the large sensor were higher than those of the small sensor for both the intrarater and interrater reliabilities. High-frequency current tended to improve the ICC for the small sensor. These results indicate reasonable repeatability of the handheld electrode arrays for EIM measurements. The findings suggest that electrode array should be selected appropriately according to the size of the tested muscle.


Assuntos
Músculo Esquelético , Miografia , Impedância Elétrica , Eletrodos , Humanos , Músculo Esquelético/fisiologia , Miografia/métodos , Reprodutibilidade dos Testes
12.
Nitric Oxide ; 117: 40-45, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34601102

RESUMO

Soluble guanylyl cyclase (sGC, also called GC1) is the main receptor for nitric oxide (NO) that catalyzes the production of the second messenger molecule, 3'5' cyclic guanosine monophosphate (cGMP) leading to vasorelaxation, and inhibition of leukocyte recruitment and platelet aggregation. Enhancing cGMP levels, through sGC agonism or inhibition of cGMP breakdown via phosphodiesterase inhibition, has yielded FDA approval for several cGMP modifier therapies for treatment of cardiovascular and pulmonary diseases. While basic research continues to improve our understanding of cGMP signaling and as new therapies evolve to elevate cGMP levels, we provide a short methodological primer for measuring cGMP and cGMP-mediated vascular relaxation for investigators.


Assuntos
GMP Cíclico/metabolismo , Guanilil Ciclase Solúvel/metabolismo , Vasodilatação/fisiologia , Animais , Artérias Mesentéricas/fisiologia , Camundongos , Miografia , Óxido Nítrico/metabolismo , Transdução de Sinais/fisiologia
13.
Physiol Res ; 70(6): 931-937, 2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-34717069

RESUMO

In functional arterial studies using wire myography, the determination of a vessel's standardized normalization factor (factor k) is an essential step to ensure optimal contraction and relaxation by the arteries when stimulated with their respective vasoactive agents and to obtain reproducible results. The optimal factor k for several arteries have been determined, however, the optimal initial tension and factor k for the arteries involved in erection remains unknown. Hence, in the present study we set out to determine the optimal factor k for the internal iliac artery, proximal and distal internal pudendal artery (IPA), and dorsal penile artery. After isolating, harvesting, and mounting the arteries from male Sprague-Dawley rats on a multi wire myograph, we tested arterial responsivity to high K+-stimulation when the factor k was set at 0.7, 0.8, 0.85, 0.9, 0.95, 1.0, 1.1, and 1.2 to determine the factor k setting that results in the greatest K+-induced active force production for each vessel type. The data showed the optimal factor k is 0.90-0.95 for the dorsal penile, distal internal pudendal and internal iliac arteries while it is 0.85-0.90 for proximal internal pudendal artery. These optimal values corresponded to initial passive tension settings of 1.10±0.16 - 1.46±0.23, 1.28±0.20 - 1.69±0.34, 1.03±0.27 - 1.33±0.31, and 1.33±0.31 - 1.77±0.43 mN/mm for the dorsal penile, distal IP, proximal IP, and internal iliac arteries, respectively.


Assuntos
Artéria Ilíaca/fisiologia , Miografia , Pênis/irrigação sanguínea , Animais , Técnicas In Vitro , Masculino , Ratos , Ratos Sprague-Dawley , Padrões de Referência , Valores de Referência , Vasoconstrição , Vasodilatação
14.
Physiol Meas ; 42(10)2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34521070

RESUMO

Objective.Electrical impedance myography (EIM) shows promise as an effective biomarker in amyotrophic lateral sclerosis (ALS). EIM applies multiple input frequencies to characterise muscle properties, often via multiple electrode configurations. Herein, we assess if non-negative tensor factorisation (NTF) can provide a framework for identifying clinically relevant features within a high dimensional EIM dataset.Approach.EIM data were recorded from the tongue of healthy and ALS diseased individuals. Resistivity and reactivity measurements were made for 14 frequencies, in three electrode configurations. This gives 84 (2 × 14 × 3) distinct data points per participant. NTF was applied to the dataset for dimensionality reduction, termed tensor EIM. Significance tests, symptom correlation and classification approaches were explored to compare NTF to using all raw data and feature selection.Main Results.Tensor EIM provides highly significant differentiation between healthy and ALS patients (p< 0.001, AUROC = 0.78). Similarly tensor EIM differentiates between mild and severe disease states (p< 0.001, AUROC = 0.75) and significantly correlates with symptoms (ρ= 0.7,p< 0.001). A trend of centre frequency shifting to the right was identified in diseased spectra, which is in line with the electrical changes expected following muscle atrophy.Significance.Tensor EIM provides clinically relevant metrics for identifying ALS-related muscle disease. This procedure has the advantage of using the whole spectral dataset, with reduced risk of overfitting. The process identifies spectral shapes specific to disease allowing for a deeper clinical interpretation.


Assuntos
Esclerose Amiotrófica Lateral , Esclerose Amiotrófica Lateral/diagnóstico , Impedância Elétrica , Humanos , Músculo Esquelético , Miografia , Língua
15.
Sensors (Basel) ; 21(11)2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34205220

RESUMO

Force myography (FMG) is a method that uses pressure sensors to measure muscle contraction indirectly. Compared with the conventional approach utilizing myoelectric signals in hand gesture recognition, it is a valuable substitute. To achieve the aim of gesture recognition at minimum cost, it is necessary to study the minimum sampling frequency and the minimal number of channels. For purpose of investigating the effect of sampling frequency and the number of channels on the accuracy of gesture recognition, a hardware system that has 16 channels has been designed for capturing forearm FMG signals with a maximum sampling frequency of 1 kHz. Using this acquisition equipment, a force myography database containing 10 subjects' data has been created. In this paper, gesture accuracies under different sampling frequencies and channel's number are obtained. Under 1 kHz sampling rate and 16 channels, four of five tested classifiers reach an accuracy up to about 99%. Other experimental results indicate that: (1) the sampling frequency of the FMG signal can be as low as 5 Hz for the recognition of static movements; (2) the reduction of channel number has a large impact on the accuracy, and the suggested channel number for gesture recognition is eight; and (3) the distribution of the sensors on the forearm would affect the recognition accuracy, and it is possible to improve the accuracy via optimizing the sensor position.


Assuntos
Gestos , Miografia , Eletromiografia , Mãos , Humanos , Fenômenos Mecânicos , Contração Muscular
16.
Sci Rep ; 11(1): 14568, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34267301

RESUMO

Acceleromyography at the adductor pollicis located in a distal part of the body may not reflect the degree of neuromuscular blockade (NMB) at the proximally located muscles manipulated during lumbar surgery. We investigated the usefulness and characteristics of acceleromyographic monitoring at the trapezius for providing moderate NMB during lumbar surgery. Fifty patients were randomized to maintain a train-of-four count 1-3 using acceleromyography at the adductor pollicis (group A; n = 25) or the trapezius (group T; n = 25). Total rocuronium dose administered intraoperatively [mean ± SD, 106.4 ± 31.3 vs. 74.1 ± 17.6 mg; P < 0.001] and surgical satisfaction (median [IQR], 7 [5-8] vs. 5 [4-5]; P < 0.001) were significantly higher in group T than group A. Lumbar retractor pressure (88.9 ± 12.0 vs. 98.0 ± 7.8 mmHg; P = 0.003) and lumbar muscle tone in group T were significantly lower than group A. Time to maximum block with an intubating dose was significantly shorter in group T than group A (44 [37-54] vs. 60 [55-65] sec; P < 0.001). Other outcomes were comparable. Acceleromyography at the trapezius muscle during lumbar surgery required a higher rocuronium dose for moderate NMB than the adductor pollicis muscle, thereby the consequent deeper NMB provided better surgical conditions. Trapezius as proximal muscle may better reflect surgical conditions of spine muscle.


Assuntos
Vértebras Lombares/cirurgia , Miografia/métodos , Bloqueio Neuromuscular/métodos , Rocurônio/administração & dosagem , Músculos Superficiais do Dorso , Adulto , Método Duplo-Cego , Feminino , Humanos , Cuidados Intraoperatórios , Masculino , Pessoa de Meia-Idade , Fármacos Neuromusculares não Despolarizantes/administração & dosagem , Dor Pós-Operatória/etiologia , Adulto Jovem
17.
J Vasc Res ; 58(6): 379-387, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34182554

RESUMO

BACKGROUND: Pressurized myography is useful for the assessment of small artery structures and function. However, this procedure requires technical expertise for sample preparation and effort to choose an appropriate sized artery. In this study, we developed an automatic artery/vein differentiation and a size measurement system utilizing machine learning algorithms. METHODS AND RESULTS: We used 654 independent mouse mesenteric artery images for model training. The model yielded an Intersection-over-Union of 0.744 ± 0.031 and a Dice coefficient of 0.881 ± 0.016. The vessel size and lumen size calculated from the predicted vessel contours demonstrated a strong linear correlation with manually determined vessel sizes (R = 0.722 ± 0.048, p < 0.001 for vessel size and R = 0.908 ± 0.027, p < 0.001 for lumen size). Last, we assessed the relation between the vessel size before and after dissection using a pressurized myography system. We observed a strong positive correlation between the wall/lumen ratio before dissection and the lumen expansion ratio (R = 0.832, p < 0.01). Using multivariate binary logistic regression, 2 models estimating whether the vessel met the size criteria (lumen size of 160-240 µm) were generated with an area under the receiver operating characteristic curve of 0.761 for the upper limit and 0.747 for the lower limit. CONCLUSION: The U-Net-based image analysis method could streamline the experimental approach.


Assuntos
Aprendizado de Máquina , Artérias Mesentéricas/diagnóstico por imagem , Veias Mesentéricas/diagnóstico por imagem , Microscopia , Redes Neurais de Computação , Animais , Pressão Arterial , Automação , Feminino , Genótipo , Interpretação de Imagem Assistida por Computador , Masculino , Artérias Mesentéricas/fisiologia , Veias Mesentéricas/fisiologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Miografia , Fenótipo , Valor Preditivo dos Testes
18.
BMC Complement Med Ther ; 21(1): 173, 2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34154575

RESUMO

BACKGROUND: An emerging body of evidence indicates that puerarin (PUE) plays an important role in the treatment of angina pectoris, myocardial ischemia-reperfusion injury, hypertension and other cardiovascular diseases, but how PUE affects the vascular remodeling of hypertensive rats has not been reported yet. This study aimed to investigate the effect and mechanism of PUE on carotid arteries of spontaneously hypertensive rats (SHR) to provide the basis for the clinical application of PUE. METHODS: Thirty male SHR and six male Wistar Kyoto rats (WKY) aged 3 months were used in this study, SHR rats were randomly divided into 5 groups, PUE(40 or 80 mg/kg/d, ip) and telmisartan (TELMI) (30 mg/kg/d, ig) were administrated for 3 months. We use DMT myography pressure-diameter system to investigate biomechanical properties of carotid arteries, 10 µM pan-classical transient receptor potential channels (TRPCs) inhibitor SKF96365, 200 nM specific TRPC6 inhibitor SAR7334 and 100 µM Orai1 inhibitor ANCOA4 were used in the mechanical test. RESULTS: PUE can significantly decrease systolic and diastolic blood pressure, long-term administration of PUE resulted in a mild reduction of thickness and inner diameter of carotid artery. PUE ameliorate NE-response and vascular remodeling mainly through inhibiting TRPCs channel activities of VSMC. CONCLUSION: PUE can ameliorate biomechanical remodeling of carotid arteries through inhibiting TRPCs channel activities of VSMC in spontaneously hypertensive rats.


Assuntos
Artéria Carótida Primitiva/diagnóstico por imagem , Isoflavonas/farmacologia , Vasodilatadores/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Artéria Carótida Primitiva/fisiopatologia , Modelos Animais de Doenças , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Miografia , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Ultrassonografia , Remodelação Vascular/efeitos dos fármacos
19.
J Biomech ; 122: 110456, 2021 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-33962326

RESUMO

Mechanomyography (MMG) is a non-invasive technique that records muscle contraction using sensors positioned on the skin's surface. Therefore, it can have its signal attenuated due to the adipose tissue, directly influencing the results. This study evaluates the influence of different mass added to a sensor's assembly and the adipose tissue on MMG signals of elbow flexor muscles. Test protocol consisted of skinfold thickness measurement of 22 volunteers, followed by applying 2-3 s electrical stimulation for muscle contraction during the acquisition of MMG signals. MMG signals were processed in the time domain, using the average of the absolute amplitude, and expressed in gravity values (G), termed here as MMG(G). Tests occurred four times with different sensor masses. MMG data were processed and analyzed statistically using Friedman and Kruskal-Wallis tests to determine the differences between the MMG signals measured with different sensor masses. The Mann-Whitney analysis indicated differences in the MMG signals between groups with different skinfold thickness. MMG(G) signals suffered attenuation with increasing sensor mass (0.4416 G to 0.94 g; 0.3902 G to 2.64 g; 0.3762 G to 5.44 g; 0.3762 G to 7.14 g) and adipose tissue.


Assuntos
Cotovelo , Músculo Esquelético , Tecido Adiposo , Eletromiografia , Humanos , Contração Muscular , Miografia
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