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1.
Trials ; 22(1): 621, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34526100

RESUMO

BACKGROUND: Colorectal cancer is associated with secondary sarcopenia (muscle loss) and myosteatosis (fatty infiltration of muscle) and patients who exhibit these host characteristics have poorer outcomes following surgery. Furthermore, patients, who undergo curative advanced rectal cancer surgery such as pelvic exenteration, are at risk of skeletal muscle loss due to immobility, malnutrition and a post-surgical catabolic state. Neuromuscular electrical stimulation (NMES) may be a feasible adjunctive treatment to help ameliorate these adverse side-effects. Hence, the purpose of this study is to investigate NMES as an adjunctive pre- and post-operative treatment for rectal cancer patients in the radical pelvic surgery setting and to provide early indicative evidence of efficacy in relation to key health outcomes. METHOD: In a phase II, double-blind, randomised controlled study, 58 patients will be recruited and randomised (1:1) to either a treatment (NMES plus standard care) or placebo (sham-NMES plus standard care) group. The intervention will begin 2 weeks pre-operatively and continue for 8 weeks after exenterative surgery. The primary outcome will be change in mean skeletal muscle attenuation, a surrogate marker of myosteatosis. Sarcopenia, quality of life, inflammatory status and cancer specific outcomes will also be assessed. DISCUSSION: This phase II randomised controlled trial will provide important preliminary evidence of the potential for this adjunctive treatment. It will provide guidance on subsequent development of phase 3 studies on the clinical benefit of NMES for rectal cancer patients in the radical pelvic surgery setting. TRIAL REGISTRATION: Protocol version 6.0; 05/06/20. ClinicalTrials.gov NCT04065984 . Registered on 22 August 2019; recruiting.


Assuntos
Terapia por Estimulação Elétrica , Neoplasias Retais , Sarcopenia , Ciclismo , Estimulação Elétrica , Terapia por Estimulação Elétrica/efeitos adversos , Humanos , Qualidade de Vida , Neoplasias Retais/complicações , Neoplasias Retais/cirurgia , Sarcopenia/diagnóstico , Sarcopenia/etiologia , Sarcopenia/terapia
2.
Medicine (Baltimore) ; 100(35): e27170, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34477175

RESUMO

BACKGROUND: To evaluate the therapeutic effects of additional electrical stimulation (ES) combined with low frequency (LF)-repetitive transcranial magnetic stimulation (rTMS) and motor imagery (MI) training on upper extremity (UE) motor function following stroke. METHODS: The participants with subacute stroke in the experimental group (n = 8) received LF rTMS + MI + active ES interventions, and those in control group (n = 9) received LF rTMS + MI + sham ES interventions. Interventions were performed 5 days a week for 2 weeks, for a total of 10 sessions. All participants were given the same dosage of conventional rehabilitation during the study period. The primary outcome measure was the UE Fugl-Meyer Assessment (FMA). The secondary outcome measures were the shoulder abduction and finger extension scores, modified Barthel Index, Purdue Pegboard Test, and finger tapping test. All scores were measured before and just after the intervention. RESULTS: After the 2-week intervention period, the FMA and modified Barthel Index scores were improved in both groups compared to baseline assessment (P < .001 in the experimental group and P = .008 in the control group). Of note, the change in FMA scores was significantly higher in the experimental group compared with that of the control group (P = .04). CONCLUSION: These results suggest that the use of LF rTMS + MI combined with additional ES lead to greater improvement of UE motor function after stroke. As such, this intervention may be a promising adjuvant therapy in UE motor training.


Assuntos
Estimulação Elétrica , Hemiplegia/terapia , Reabilitação do Acidente Vascular Cerebral , Estimulação Magnética Transcraniana , Extremidade Superior/fisiologia , Idoso , Feminino , Hemiplegia/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recuperação de Função Fisiológica , Acidente Vascular Cerebral/complicações , Cuidados Semi-Intensivos
3.
Int Braz J Urol ; 47(6): 1150-1159, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34469668

RESUMO

PURPOSE: To evaluate the efficacy of intravaginal electrical stimulation (IVES) added to bladder training (BT) on incontinence-related quality of life (QoL) and clinical parameters in women with idiopathic overactive bladder (OAB). MATERIALS AND METHODS: Sixty-two women with idiopathic OAB were randomized into two groups using the random numbers generator as follows: Group 1 received BT alone (n:31), and Group 2 received BT+IVES (n:31). IVES was performed for twenty minutes three days a week over a course of eight weeks for a total of 24 sessions. Patients were evaluated in terms of incontinence severity (24-hour pad test), pelvic floor muscles strength (perineometer), 3-day voiding diary (frequency of voiding, nocturia, incontinence episodes and number of pads), symptom severity (OAB-V8), incontinence-related QoL (IIQ-7), treatment success (positive response rate), cure/improvement rate and treatment satisfaction (Likert scale). RESULTS: A statistically significant improvement was found in all parameters for all groups at the end of the treatment compared to the baseline values except pelvic floor muscles strength in Group 1 (p < 0.05). At the end of treatment, incontinence severity, frequency of voiding, nocturia, incontinence episodes, number of pads, symptom severity, and QoL were significantly improved in Group 2 compared to Group 1 (p < 0.05). Treatment satisfaction, cure/improvement, and positive response rates were significantly higher in group 2 compared to Group 1 (p < 0.05). CONCLUSION: We conclude that BT+IVES were more effective than BT alone on both incontinence-related QoL and clinical parameters in women with idiopathic OAB.


Assuntos
Bexiga Urinária Hiperativa , Estimulação Elétrica , Feminino , Humanos , Diafragma da Pelve , Estudos Prospectivos , Qualidade de Vida , Inquéritos e Questionários , Bexiga Urinária Hiperativa/terapia
4.
Artigo em Chinês | MEDLINE | ID: mdl-34521167

RESUMO

Objective: To study the oropharyngeal sensory function by Current Perception Threshold(CPT) detection, to explore the detection method of oropharyngeal sensory function in normal population, and to analyze the possible influencing factors. Methods: Fifty-eight normal subjects were included prospectively in this study. Age, gender, body mass index (BMI) were collected. The age of the subjects ranged from 20 to 76 (43.27±13.52) years old. There were 34 females with 17 in childbearing period and 17 in menopause; and 24 males were included.In all the cases, 6 cases were in low BMI, 39 cases were in normal BMI, 10 cases were overweight and 3 cases were suffering from obesity. The CPT system of Neurometer was used to stimulate bilateral palatoglossal arch and tongue base.The current used was 2000 Hz, 250 Hz and 5 Hz respectively.The function of type Aß, Aδ and C sensory nerve fibers were tested and the CPT values were recorded.The values were inversely proportional to pharyngeal sensation function.To evaluate the oropharyngeal sensory function of the subjects, the CPT values of each frequency at each testing point were compared. SPSS 25.0 software was used for statistical analysis. Results: The CPT value of palatoglossal arch was significantly lower than that of tongue base (t=-2.58,-2.65,-2.54,-2.47,-2.37,-2.77,P<0.05), 2 000 Hz>250 Hz>5 Hz, and there was no significant difference between left and right sides(t=-0.03,-0.51,-0.49,0.06,-0.16,0.13,P>0.05). The CPT value of male was slightly higher than that of female (t=0.92,1.55,0.27,0.78,1.44,1.26,0.35,0.77,1.27,0.24,0.78,0.96,P>0.05). The CPT values of women in childbearing period were significantly less than those in menopausal women (t=-3.90,-3.64,-2.14,-4.20,-4.28,-4.28,-3.52,-4.46,-3.41,-3.63,-4.66,-2.86,P<0.05). The CPT value increased with age, and the values of all frequency of 20 to 30 years old group was significantly lower than those of subjects over 40 years old at each point (The t values of bilateral palatoglossal arch at 2 000 Hz were -5.57,-6.22,-10.18,-11.00;the t values of bilateral palatoglossal arch at 250 Hz were -6.39,-8.79,-6.39,-15.61;the t values of bilateral palatoglossal arch at 5 Hz were -7.09, -5.57, -9.26, -15.23;the t values of tongue base at 2 000 Hz were -3.11,-3.88,-7.60,-8.55;the t values of tongue base at 250 Hz were -6.31,-10.59,-8.52,-10.60;the t values of tongue baseat 5 Hz were -6.69,-5.09,-8.70,-7.07,P<0.05).The values at all frequencies and testing points of 30-40 years old group were significantly lower than those of all subjects over 60 years old (The t values of bilateral palatoglossal arch at 2 000 Hz were -10.91,-12.42;the t values of bilateral palatoglossal arch at 250 Hz were -6.25,-10.87;the t values of bilateral palatoglossal arch at 5 Hz were -5.53,-11.01;the t values of tongue base at 2 000 Hz were -8.62,-10.12;the t values of tongue base at 250 Hz were -6.89,-7.82;the t values of tongue base at 5 Hz were -6.13,-6.48,P<0.05). Conclusions: CPT can be used to evaluate oropharyngeal sensory function. The sensitivity of tongue base is lower than that of palatoglossal arch, there is no significant difference in oropharyngeal sensory function between male and female,between left and right sides. There are many factors influencing oropharyngeal sensory function. Age, hormone level changes may affect the sensitivity of oropharyngeal sensory function.


Assuntos
Fibras Nervosas , Sensação , Adulto , Idoso , Estimulação Elétrica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Faringe , Limiar Sensorial , Adulto Jovem
6.
7.
Artigo em Inglês | MEDLINE | ID: mdl-34398757

RESUMO

Cochlear implants are very well established in the rehabilitation of hearing loss and are regarded as the most successful neuroprostheses to date. While a lot of progress has also been made in the neighboring field of specific vestibular implants, some diseases affect the entire inner ear, leading to both hearing and vestibular hypo- or dysfunction. The proximity of the cochlear and vestibular organs suggests a single combined implant as a means to alleviate the associated impairments. While both organs can be stimulated in a similar way with electric pulses applied through implanted electrodes, the typical phase durations needed in the vestibular system seem to be substantially larger than those typically needed in the cochlear system. Therefore, when using sequential stimulation in a combined implant, the pulse stream to the cochlea is interrupted by comparatively large gaps in which vestibular stimulation can occur. We investigate the impact of these gaps in the auditory stream on speech perception. Specifically, we compare a number of stimulation strategies with different gap lengths and distributions and evaluate whether it is feasible to use them without having a noticeable decline in perception and quality of speech. This is a prerequisite for any practicable stimulation strategy of a combined system and can be investigated even in recipients of a normal cochlear implant. Our results show that there is no significant deterioration in speech perception for the different strategies examined in this paper, leaving the strategies as viable candidates for prospective combined cochleo-vestibular implants.


Assuntos
Implante Coclear , Implantes Cocleares , Surdez , Percepção da Fala , Estimulação Acústica , Estimulação Elétrica , Humanos , Estudos Prospectivos
8.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 38(4): 630-637, 2021 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-34459161

RESUMO

Transcranial direct current stimulation (tDCS) is a non-invasive low-current brain stimulation technique, which is mainly based on the different polarity of electrode stimulation to make the activation threshold of neurons different, thereby regulating the excitability of the cerebral cortex. In this paper, healthy subjects were randomly divided into three groups: anodal stimulation group, cathodal stimulation group and sham stimulation group, with 5 subjects in each group. Then, the performance data of the three groups of subjects were recorded before and after stimulation to test their mental rotation ability, and resting state and task state electroencephalogram (EEG) data were collected. Finally, through comparative analysis of the behavioral data and EEG data of the three groups of subjects, the effect of electrical stimulation of different polarities on the three-dimensional mental rotation ability was explored. The results of the study found that the correct response time/accuracy rate and the accuracy rate performance of the anodal stimulation group were higher than those of the cathodal stimulation and sham stimulation groups, and there was a significant difference ( P < 0.05). The alpha wave power analysis found that the mental rotation mainly activates the frontal lobe, central area, parietal lobe and occipital lobe. In the anodal stimulation group, the alpha wave power changed significantly in the frontal lobe and occipital lobe ( P < 0.05). The results of this paper show that anodal stimulation group can improve the mental rotation ability of the subjects to a certain extent. The results of this paper can provide important theoretical support for further research on the mechanism of tDCS on mental rotation ability.


Assuntos
Estimulação Transcraniana por Corrente Contínua , Estimulação Elétrica , Eletroencefalografia , Lobo Frontal , Humanos , Tempo de Reação
9.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 38(4): 638-646, 2021 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-34459162

RESUMO

Transcranial direct current stimulation (tDCS) is a brain stimulation intervention technique, which has the problem of different criteria for the selection of stimulation parameters. In this study, a four-layer real head model was constructed. Based on this model, the changes of the electric field distribution in the brain with the current intensity, electrode shape, electrode area and electrode spacing were analyzed by using finite element simulation technology, and then the optimal scheme of electrical stimulation parameters was discussed. The results showed that the effective stimulation region decreased and the focusing ability increased with the increase of current intensity. The normal current density of the quadrilateral electrode was obviously larger than that of the circular electrode, which indicated that the quadrilateral electrode was more conducive to current stimulation of neurons. Moreover, the effective stimulation region of the quadrilateral electrode was more concentrated and the focusing ability was stronger. The focusing ability decreased with the increase of electrode area. Specifically, the focusing tended to increase first and then decrease with the increase of electrode spacing and the optimal electrode spacing was 64.0-67.2 mm. These results could provide some basis for the selection of electrical stimulation parameters.


Assuntos
Estimulação Transcraniana por Corrente Contínua , Encéfalo , Estimulação Elétrica , Eletrodos , Cabeça
10.
Artigo em Inglês | MEDLINE | ID: mdl-34379593

RESUMO

Functional electrical stimulation (FES) is often used, typically in an open-loop manner, to restore paralyzed motor function for daily living activities. Several feedback control strategies have been developed to improve the performance and usability of FES-evoked movement. However, most of them have been position controllers, while the control strategy for human movement has been known as impedance modulation. Moreover, few studies have attempted to use antagonistic co-contraction for FES feedback control despite its expected benefits, such as enhanced stability and performance and better rehabilitation outcome. In this paper, we propose a robust impedance controller for FES that can adjust the intrinsic joint stiffness using co-contraction. It consists of an impedance control law based on time-delay estimation to compensate for the nonlinear uncertain joint dynamics and an antagonistic muscle co-contraction allocator to address the intrinsic joint stiffness caused by the co-contraction. The proposed controller was implemented on the ankle joints of five healthy subjects to simulate a standing balance situation. The results verified that the proposed controller can achieve desired impedance accurately by adjusting the intrinsic stiffness that stems from the change in the amount of co-contraction (up to 48.4% better impedance achievement with high desired stiffness).


Assuntos
Articulação do Tornozelo , Contração Muscular , Impedância Elétrica , Estimulação Elétrica , Humanos , Músculo Esquelético , Músculos
11.
Neuroimage Clin ; 31: 102778, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34375883

RESUMO

Effective seizure control remains challenging for about 30% of epilepsy patients who are resistant to present-day pharmacotherapy. Novel approaches that not only reduce the severity and frequency of seizures, but also have limited side effects are therefore desirable. Accordingly, various neuromodulation approaches such as cortical electrical stimulation have been implemented to reduce seizure burden; however, the underlying mechanisms are not completely understood. Given that the initiation and spread of epileptic seizures critically depend on cortical excitability, understanding the neuromodulatory effects of cortical electrical stimulation on cortical excitability levels is paramount. Based on observations that synchronization in the electrocorticogram closely tracks brain excitability level, the effects of low-frequency (1 Hz) intracranial brain stimulation on the levels of cortical phase synchronization before, during, and after 1 Hz electrical stimulation were assessed in twelve patients. Analysis of phase synchronization levels across three broad frequency bands (1-45 Hz, 55-95 Hz, and 105-195 Hz) revealed that in patients with stimulation sites in the neocortex, phase synchronization levels were significantly reduced within the 55-95 Hz and 105-195 Hz bands during post-stimulation intervals compared to baseline; this effect persisted for at least 30 min post-stimulation. Similar effects were observed when phase synchronization levels were examined in the classic frequency bands, whereby a significant reduction was found during the post-stimulation intervals in the alpha, beta, and gamma bands. The anatomical extent of these effects was then assessed. Analysis of the results from six patients with intracranial electrodes in both hemispheres indicated that reductions in phase synchronization in the 1-45 Hz and 55-95 Hz frequency ranges were more prominent in the stimulated hemisphere. Overall, these findings demonstrate that low-frequency electrical stimulation reduces phase synchronization and hence cortical excitability in the human brain. Low-frequency stimulation of the epileptic focus may therefore contribute to the prevention of impending epileptic seizures.


Assuntos
Excitabilidade Cortical , Neocórtex , Sincronização Cortical , Estimulação Elétrica , Humanos , Convulsões
12.
J Neural Eng ; 18(4)2021 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-34400592

RESUMO

Objective.We derive and demonstrate how residual voltage (RV) from a biphasic electrical stimulation pulse can be used to recognize degradation at the electrode-tissue interface.Approach.Using a first order model of the electrode-tissue interface and a rectangular biphasic stimulation current waveform, we derive the equations for RV as well as RV growth over several stimulation pulses. To demonstrate the use of RV for damage detection, we simulate accelerated damage on sputtered iridium oxide film (SIROF) electrodes using potential cycling. RV measurements of the degraded electrodes are compared against standard characterization methods of cyclic voltammetry and electrochemical impedance spectroscopy.Main results.Our theoretical discussion illustrates how an intrinsic RV arises even from perfectly balanced biphasic pulses due to leakage via the charge-transfer resistance. Preliminary data inin-vivorat experiments follow the derived model of RV growth, thereby validating our hypothesis that RV is a characteristic of the electrode-tissue interface. RV can therefore be utilized for detecting damage at the electrode. Our experimental results for damage detection show that delamination of SIROF electrodes causes a reduction in charge storage capacity, which in turn reflects a measurable increase in RV.Significance.Chronically implanted electrical stimulation systems with multi-electrode arrays have been the focus of physiological engineering research for the last decade. Changes in RV over time can be a quick and effective method to identify and disconnect faulty electrodes in large arrays. Timely diagnoses of electrode status can ensure optimal long term operation, and prevent further damage to the tissue near these electrodes.


Assuntos
Eletrodos Implantados , Impedância Elétrica , Estimulação Elétrica , Eletrodos
13.
J Neural Eng ; 18(4)2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34407519

RESUMO

Objective.Invasive simultaneous stimulation and recording from intracranial electrodes and microwire arrays were used to investigate direct cortical responses to single pulses of electrical stimulation in humans.Approach.Microwire contacts measured surface potentials in cortical microdomains at a distance of 2-6 mm from the intracranial electrode. Direct cortical responses to stimulation (<20 ms) consisted of a larger surface negative potentials.Main results. The latencies of these responses were directly or inversely correlated with distances between the intracranial electrode and microwire contacts. We hypothesize that surface negative potentials reflected local synchronous depolarization of apical dendrites of pyramidal neurons in cortical microdomains in the superficial cortical layer and resulted from the activation of gray matter axons that delivered excitatory inputs to apical dendrites after cortical stimulation. We further hypothesized that the positive or inverse distance-latency correlations of the recorded negative responses were measured depending on whether activation of neurons originated at one (crown) or multiple (crown, lip, bank) sites throughout the gyrus simultaneously. The inverse distance-latency correlations then reflected the spatiotemporal superposition of different nearby sources of neuronal recruitment in the gyrus. To prove this hypothesis, we built an anatomically informed and biophysically realistic cortical network model and simulated early responses of cortical neurons to electrical stimulation in this cortical network model. The model simulations yielded negative potentials in simulated microdomains in the cortical model consistent with those recorded from humans. The model predicted sensitivity of cortical responses to the alignment of the stimulating electrode and microwire array with respect to the cortical gyrus and confirmed that gyral geometry has a major impact on direct neuronal recruitment, the timing, and the time course of neuronal activation in cortical microdomains.Significance.In this work, we demonstrated how the high-resolution forward network models can be used for better understanding and detailed prediction of cortical stimulation effects. Accurate predictive modeling tools are needed for the progress of brain stimulation therapies.


Assuntos
Neurônios , Células Piramidais , Axônios , Estimulação Elétrica , Humanos
14.
FASEB J ; 35(9): e21860, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34411340

RESUMO

Desminopathy is the most common intermediate filament disease in humans. The most frequent mutation causing desminopathy in patients is a R350P DES missense mutation. We have developed a rat model with an analogous mutation in R349P Des. To investigate the role of R349P Des in mechanical loading, we stimulated the sciatic nerve of wild-type littermates (WT) (n = 6) and animals carrying the mutation (MUT) (n = 6) causing a lengthening contraction of the dorsi flexor muscles. MUT animals showed signs of ongoing regeneration at baseline as indicated by a higher number of central nuclei (genotype: P < .0001). While stimulation did not impact central nuclei, we found an increased number of IgG positive fibers (membrane damage indicator) after eccentric contractions with both genotypes (stimulation: P < .01). Interestingly, WT animals displayed a more pronounced increase in IgG positive fibers with stimulation compared to MUT (interaction: P < .05). In addition to altered histology, molecular signaling on the protein level differed between WT and MUT. The membrane repair protein dysferlin decreased with eccentric loading in WT but increased in MUT (interaction: P < .05). The autophagic substrate p62 was increased in both genotypes with loading (stimulation: P < .05) but tended to be more elevated in WT (interaction: P = .05). Caspase 3 levels, a central regulator of apoptotic cell death, was increased with stimulation in both genotypes (stimulation: P < .01) but more so in WT animals (interaction: P < .0001). Overall, our data indicate that R349P Des rats have a lower susceptibility to structural muscle damage of the cytoskeleton and sarcolemma with acute eccentric loading.


Assuntos
Desmina/genética , Contração Muscular , Músculo Esquelético/lesões , Músculo Esquelético/metabolismo , Mutação , Doença Aguda , Animais , Apoptose , Doença Crônica , Colágeno/metabolismo , Modelos Animais de Doenças , Estimulação Elétrica , Feminino , Masculino , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/patologia , Músculo Esquelético/patologia , Ratos , Risco
15.
Zhonghua Yi Xue Za Zhi ; 101(31): 2443-2447, 2021 Aug 17.
Artigo em Chinês | MEDLINE | ID: mdl-34399557

RESUMO

Objective: To investigate the characteristics of low frequency repetitive nerve stimulation (RNS) in patients with myasthenia gravis (MG) and analyze the correlation between RNS results and clinical characteristics. Methods: The clinical and electrophysiological data of 107 MG patients who were admitted to Guangdong Provincial People's Hospital and underwent electromyography (EMG) between September 2015 to September 2020 were retrospectively reviewed. The characteristics of low frequency RNS in ocular MG and generalized MG patients were analyzed. Patients were divided into RNS-negative group and RNS-positive group according to the RNS results. The clinical features, serological and thymic CT findings, thymic pathology were collected and compared. Binary logistic regression analysis was used to analyze the related factors of low frequency RNS. Results: Generalized MG (73.0%, 46/63) showed a lower positive rate of low frequency RNS compared to ocular MG (34.1%, 15/44) (P<0.001). In generalized MG, the positive rate of low frequency RNS in accessory nerve (68.3%, 43 cases) and facial nerve (52.4%, 33 cases) was higher than that in ulnar nerve (14.3%, 9 cases) (P<0.001). The decrease rate of compound muscle action potential (CMAP) in facial nerve (32%±11%) was higher than that in ocular muscle type (22%±7%) in RNS-positive group (P=0.011). Patients with positive facial nerve RNS were more likely to involve the throat muscles than those with negative result [22 cases (52.4%) compared with 17 cases (26.2%), P=0.006]. RNS-positive group showed a significantly higher quantitative myasthenia gravis (QMG) score than that of negative group (P<0.001). In ocular MG, patients with positive RNS showed a later onset (P=0.021), higher acetylcholine receptor (AChR) antibody-positive rate (P=0.03) and QMG score (P<0.001). Additionally, In generalized MG, patients with positive RNS showed a significantly higher AChR antibody-positive rate (P=0.023) and QMG score (P<0.001). The logistic regression analysis showed that QMG score [OR(95%CI)=1.66(1.36-2.03), P<0.001] and positive AChR antibody [OR(95%CI)=5.45(1.28-23.14), P=0.022] were independently related to abnormal RNS. Conclusions: Low frequency RNS is more sensitive in generalized MG. The stimulation of facial and accessory nerves increases the positive rate of RNS in MG patients. Abnormal results of low frequency RNS tend to be combined with positive AChR antibody and higher QMG score, reflecting the severity of muscle weakness. Therefore, serological examination and early intervention are required for those with abnormal RNS.


Assuntos
Miastenia Gravis , Estimulação Elétrica , Eletromiografia , Humanos , Estudos Retrospectivos , Nervo Ulnar
16.
BMJ Case Rep ; 14(8)2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34389591

RESUMO

We report a 69 year old who suffered a cardioembolic ischaemic stroke on 23 September 2019, which resulted in a left hemiplegia with motor impairment in upper and lower extremities that made impossible for her to use the affected arm in daily living activities. The person commenced her comprehensive physiotherapy programme based on functional electrical stimulation (FES) in Fesia Clinic rehabilitation centre in October 2020. A multifield technology-based FES device was used, which allowed to train different selective movements in isolation and combined with mirror therapy, achieving excellent functional outcomes.


Assuntos
Isquemia Encefálica , Terapia por Estimulação Elétrica , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Idoso , Estimulação Elétrica , Feminino , Mãos , Humanos , Acidente Vascular Cerebral/complicações , Extremidade Superior
17.
J Neural Eng ; 18(4)2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34330105

RESUMO

Peripheral nerve stimulation is an effective treatment for various neurological disorders. The method of activation and stimulation parameters used impact the efficacy of the therapy, which emphasizes the need for tools to model this behavior. Computational modeling of nerve stimulation has proven to be a useful tool for estimating stimulation thresholds, optimizing electrode design, and exploring previously untested stimulation methods. Despite their utility, these tools require access to and familiarity with several pieces of specialized software. A simpler, streamlined process would increase accessibility significantly. We developed an open-source, parameterized model with a simple online user interface that allows user to adjust up to 36 different parameters (https://nervestimlab.utdallas.edu). The model accurately predicts fiber activation thresholds for nerve and electrode combinations reported in literature. Additionally, it replicates characteristic differences between stimulation methods, such as lower thresholds with monopolar stimulation as compared to tripolar stimulation. The model predicted that the difference in threshold between monophasic and biphasic waveforms, a well-characterized phenomenon, is not present during stimulation with bipolar electrodes.In vivotesting on the rat sciatic nerve validated this prediction, which has not been previously reported. The accuracy of the model when compared to previous experiments, as well as the ease of use and accessibility to generate testable hypotheses, indicate that this software may represent a useful tool for a variety of nerve stimulation applications.


Assuntos
Tecido Nervoso , Animais , Estimulação Elétrica , Eletrodos , Ratos , Nervo Isquiático
18.
Int J Mol Sci ; 22(11)2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34199392

RESUMO

Coordination of four-limb movements during quadrupedal locomotion is controlled by supraspinal monoaminergic descending pathways, among which serotoninergic ones play a crucial role. Here we investigated the locomotor pattern during recovery from blockade of 5-HT7 or 5-HT2A receptors after intrathecal application of SB269970 or cyproheptadine in adult rats with chronic intrathecal cannula implanted in the lumbar spinal cord. The interlimb coordination was investigated based on electromyographic activity recorded from selected fore- and hindlimb muscles during rat locomotion on a treadmill. In the time of recovery after hindlimb transient paralysis, we noticed a presence of an unusual pattern of quadrupedal locomotion characterized by a doubling of forelimb stepping in relation to unaffected hindlimb stepping (2FL-1HL) after blockade of 5-HT7 receptors but not after blockade of 5-HT2A receptors. The 2FL-1HL pattern, although transient, was observed as a stable form of fore-hindlimb coupling during quadrupedal locomotion. We suggest that modulation of the 5-HT7 receptors on interneurons located in lamina VII with ascending projections to the forelimb spinal network can be responsible for the 2FL-1HL locomotor pattern. In support, our immunohistochemical analysis of the lumbar spinal cord demonstrated the presence of the 5-HT7 immunoreactive cells in the lamina VII, which were rarely 5-HT2A immunoreactive.


Assuntos
Locomoção/genética , Receptor 5-HT2A de Serotonina/genética , Receptores de Serotonina/genética , Traumatismos da Medula Espinal/genética , Animais , Ciproeptadina/farmacologia , Estimulação Elétrica , Eletromiografia , Membro Anterior/efeitos dos fármacos , Membro Anterior/fisiopatologia , Membro Posterior/efeitos dos fármacos , Membro Posterior/fisiopatologia , Humanos , Locomoção/efeitos dos fármacos , Região Lombossacral/fisiopatologia , Ratos , Receptor 5-HT2A de Serotonina/efeitos dos fármacos , Receptores de Serotonina/efeitos dos fármacos , Serotonina/genética , Serotonina/metabolismo , Antagonistas do Receptor 5-HT2 de Serotonina/farmacologia , Medula Espinal , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/patologia , Coluna Vertebral/efeitos dos fármacos , Coluna Vertebral/fisiopatologia
19.
Neuropsychologia ; 160: 107965, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34303719

RESUMO

Risk-taking behaviour is an essential aspect of our interactions with the environment. Here we investigated whether vestibular inputs influence behavioural measurement of risk-taking propensity. We have combined bipolar Galvanic Vestibular Stimulation (GVS) with a well-known and established risk-taking behaviour task, namely the Balloon Analogue Risk Task (BART). A sham stimulation was used to control for non-specific effects. Left-anodal and right-cathodal GVS (L-GVS), which preferentially activates the vestibular projections in the right hemisphere, decreased the willingness to take risk during the BART compared with right-anodal and left-cathodal GVS (R-GVS), which activates the left hemisphere. This proved a specific vestibular effect which depends on GVS polarity. Conversely, no generic vestibular effect, defined as the adjusted average of L-GVS and R-GVS conditions compared to sham, emerged, excluding non-specific vestibular effects. Our results confirmed recent findings of a vestibular contribution to decision-making and strategy control behaviour. We suggest that the vestibular-mediated balancing of risk seeking behaviour is an important element of the brain's capacity to adapt to the environment.


Assuntos
Lateralidade Funcional , Vestíbulo do Labirinto , Estimulação Elétrica , Humanos , Assunção de Riscos , Sensação
20.
J Neural Eng ; 18(4)2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34320481

RESUMO

Objective.Intracortical microstimulation (ICMS) in somatosensory cortex can restore sensation to people with spinal cord injury. However, the recording quality from implanted microelectrodes can degrade over time and limitations in stimulation longevity have been considered a potential barrier to the clinical use of ICMS. Our objective was to evaluate recording stability of intracortical electrodes implanted in the motor and somatosensory cortex of one person. The electrodes in motor cortex had platinum tips and were not stimulated, while the electrodes in somatosensory cortex had sputtered iridium oxide film (SIROF) tips and were stimulated. Additionally, we measured how well ICMS was able to evoke sensations over time.Approach. We implanted microelectrode arrays with SIROF tips in the somatosensory cortex (SIROF-sensory) of a human participant with a cervical spinal cord injury. We regularly stimulated these electrodes to evoke tactile sensations on the hand. Here, we quantify the stability of these electrodes in comparison to non-stimulated platinum electrodes implanted in the motor cortex (platinum-motor) over 1500 days with recorded signal quality and electrode impedances. Additionally, we quantify the stability of ICMS-evoked sensations using detection thresholds.Main results. We found that recording quality, as assessed by the number of electrodes with high-amplitude waveforms (>100µV peak-to-peak), peak-to-peak voltage, noise, and signal-to-noise ratio, decreased over time on SIROF-sensory and platinum-motor electrodes. However, SIROF-sensory electrodes were more likely to continue to record high-amplitude signals than platinum-motor electrodes. Interestingly, the detection thresholds for stimulus-evoked sensations decreased over time from a median of 31.5µA at day 100-10.4µA at day 1500, with the largest changes occurring between day 100 and 500.Significance. These results demonstrate that ICMS in human somatosensory cortex can be provided over long periods of time without deleterious effects on recording or stimulation capabilities. In fact, the sensitivity to stimulation improved over time.


Assuntos
Mãos , Córtex Somatossensorial , Estimulação Elétrica , Eletrodos Implantados , Humanos , Microeletrodos , Tato
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