scholarly journals Effects of Noninvasive Low-Intensity Focus Ultrasound Neuromodulation on Spinal Cord Neurocircuits In Vivo

2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Ye-Hui Liao ◽  
Mo-Xian Chen ◽  
Shao-Chun Chen ◽  
Kai-Xuan Luo ◽  
Bin Wang ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Evoked Potentials ◽  
Muscle Contraction ◽  
Soleus Muscle ◽  
Focused Ultrasound ◽  
Rating Scale ◽  
Coagulation Necrosis ◽  
Enzyme Linked Immunosorbent Assay ◽  
Nissl Staining ◽  
Low Intensity

Although neurocircuits can be activated by focused ultrasound stimulation, it is unclear whether this is also true for spinal cord neurocircuits. In this study, we used low-intensity focused ultrasound (LIFU) to stimulate lumbar 4–lumbar 5 (L4–L5) segments of the spinal cord of normal Sprague Dawley rats with a clapper. The activation of the spinal cord neurocircuits enhanced soleus muscle contraction as measured by electromyography (EMG). Neuronal activation and injury were assessed by EMG, western blotting (WB), immunofluorescence, hematoxylin and eosin (H&E) staining, Nissl staining, enzyme-linked immunosorbent assay (ELISA), immunohistochemistry (IHC), somatosensory evoked potentials (SEPs), motor evoked potentials (MEPs), and the Basso–Beattie–Bresnahan locomotor rating scale. When the LIFU intensity was more than 0.5 MPa, LIFU stimulation induced soleus muscle contraction and increased the EMG amplitudes ( P < 0.05 ) and the number of c-fos- and GAD65-positive cells ( P < 0.05 ). When the LIFU intensity was 3.0 MPa, the LIFU stimulation led to spinal cord damage and decreased SEP amplitudes for electrophysiological assessment ( P < 0.05 ); this resulted in coagulation necrosis, structural destruction, neuronal loss in the dorsal horn by H&E and Nissl staining, and increased expression of GFAP, IL-1β, TNF-α, and caspase-3 by IHC, ELISA, and WB ( P < 0.05 ). These results show that LIFU can activate spinal cord neurocircuits and that LIFU stimulation with an irradiation intensity ≤1.5 MPa is a safe neurostimulation method for the spinal cord.

scholarly journals Effects of electrode size and placement on comfort and efficiency during low-intensity neuromuscular electrical stimulation of quadriceps, hamstrings and gluteal muscles

2022 ◽  
Vol 14 (1) ◽  
Author(s):  
J. Flodin ◽  
R. Juthberg ◽  
P. W. Ackermann
Keyword(s):  
Electrical Stimulation ◽  
Muscle Contraction ◽  
Current Density ◽  
Rating Scale ◽  
Numerical Rating Scale ◽  
Neuromuscular Electrical Stimulation ◽  
Gluteus Maximus ◽  
Major Drawback ◽  
Electrode Size ◽  
Low Intensity

Abstract Background Neuromuscular electrical stimulation (NMES) may prevent muscle atrophy, accelerate rehabilitation and enhance blood circulation. Yet, one major drawback is that patient compliance is impeded by the discomfort experienced. It is well-known that the size and placement of electrodes affect the comfort and effect during high-intensity NMES. However, during low-intensity NMES the effects of electrode size/placement are mostly unknown. Therefore, the purpose of this study was to investigate how electrode size and pragmatic placement affect comfort and effect of low-intensity NMES in the thigh and gluteal muscles. Methods On 15 healthy participants, NMES-intensity (mA) was increased until visible muscle contraction, applied with three electrode sizes (2 × 2 cm, 5 × 5 cm, 5 × 9 cm), in three different configurations on quadriceps and hamstrings (short-transverse (ST), long-transverse (LT), longitudinal (L)) and two configurations on gluteus maximus (short-longitudinal (SL) and long-longitudinal (LL)). Current–density (mA/cm2) required for contraction was calculated for each electrode size. Comfort was assessed with a numerical rating scale (NRS, 0–10). Significance was set to p < 0.05 and values were expressed as median (inter-quartile range). Results On quadriceps the LT-placement exhibited significantly better comfort and lower current intensity than the ST- and L-placements. On hamstrings the L-placement resulted in the best comfort together with the lowest intensity. On gluteus maximus the LL-placement demonstrated better comfort and required less intensity than SL-placement. On all muscles, the 5 × 5 cm and 5 × 9 cm electrodes were significantly more comfortable and required less current–density for contraction than the 2 × 2 cm electrode. Conclusion During low-intensity NMES-treatment, an optimized electrode size and practical placement on each individual muscle of quadriceps, hamstrings and gluteals is crucial for comfort and intensity needed for muscle contraction.

Sustained Muscle Contractions Maintained by Autonomous Neuronal Activity Within the Human Spinal Cord

2003 ◽  
Vol 90 (4) ◽  
pp. 2090-2097 ◽  
Author(s):  
Daichi Nozaki ◽  
Noritaka Kawashima ◽  
Yu Aramaki ◽  
Masami Akai ◽  
Kimitaka Nakazawa ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Muscle Contraction ◽  
Soleus Muscle ◽  
Primary Motor Cortex ◽  
Human Subjects ◽  
Silent Period ◽  
Muscle Contractions ◽  
Electromyographic Activity ◽  
Human Spinal Cord ◽  
Train Stimulation

It is well known that muscle contraction can be easily evoked in the human soleus muscle by applying single-pulse electrical stimulation to the tibial nerve at the popliteal fossa. We herein reveal the unexpected phenomenon of muscle contractions that can be observed when train stimulation is used instead. We found, in 11 human subjects, that transient electrical train stimulation (1-ms pulses, 50 Hz, 2 s) was able to induce sustained muscle contractions in the soleus muscle that outlasted the stimulation period for greater than 1 min. Subjects were unaware of their own muscle activity, suggesting that this is an involuntary muscle contraction. In fact, the excitability of the primary motor cortex (M1) with the sustained muscle contractions evaluated by transcranial magnetic stimulation was lower than the excitability with voluntary muscle contractions even when both muscle contraction levels were matched. This finding indicates that M1 was less involved in maintaining the muscle contractions. Furthermore, the muscle contractions did not come from spontaneous activity of muscle fibers or from reverberating activity within closed neuronal circuits involving motoneurons. These conclusions were made based on the respective evidence: 1) the electromyographic activity was inhibited by stimulation of the common peroneal nerve that has inhibitory connections to the soleus motoneuron pool and 2) it was not abolished after stopping the reverberation (if any) for approximately 100 ms by inducing the silent period that followed an H-reflex. These findings indicate that the sustained muscle contractions induced in this study are most likely to be maintained by autonomous activity of motoneurons and/or interneurons within the human spinal cord.

Preliminary Research on Depression Treatment: Combination of Transcranial Magnetic Stimulation and MRI-Guided Low-Intensity Focused Ultrasound Pulsation

2020 ◽  
Vol 10 (3) ◽  
pp. 677-680
Author(s):  
Xu Li ◽  
Fei Weng ◽  
Wenbo Sun ◽  
Ruolan Liu ◽  
Haibo Xu
Keyword(s):  
Transcranial Magnetic Stimulation ◽  
Magnetic Stimulation ◽  
Focused Ultrasound ◽  
Rating Scale ◽  
Geriatric Depression Scale ◽  
Depression Scale ◽  
Clinical Results ◽  
Control Group ◽  
Low Intensity ◽  
Treatment Of Depression

Depression (major depressive disorder) is a common but serious mood disorder. When traditional medication treatment does not reduce symptoms, transcranial magnetic stimulation (TMS) has been approved by the Food and Drug Administration (FDA), neuromodulation has become increasingly relevant to clinical research. However, TMS has significant drawback in the lack of depth and special specificity. In the last few years low-intensity focused ultrasound pulsation (LIFUP) has been used to be focused noninvasively through the skull anywhere within the brain, together with functional magnetic resonance imaging (fMRI) guided techniques, LIFUP can be applied to deep structures with greater spatial precision. In this manuscript, combination of TMS and fMRI-guided LIFUP on the treatment of depression was proposed to achieve the benefits of both. The data of the combined methods demonstrate significantly better clinical results in comparison to the control group, as measured by the Hamilton Rating Scale for Depression (HAM-D) scale, Geriatric Depression scale (GDS) and the Pittsburgh Sleep Quality Index (PSQI) with low adverse reaction.

Preliminary effects of low-intensity focused ultrasound treatment program for cancer-related neuropathic pain

2021 ◽  
Author(s):  
Ankur A Patel ◽  
Max Zhukosvky ◽  
Shawn Sidharthan ◽  
Rohan Jotwani ◽  
Neal Rakesh ◽  
...  
Keyword(s):  
Neuropathic Pain ◽  
Peripheral Neuropathy ◽  
Focused Ultrasound ◽  
Rating Scale ◽  
Pulse Mode ◽  
Side Effect Profile ◽  
Low Intensity ◽  
Numeric Pain Rating Scale ◽  
Pain Rating Scale ◽  
Viable Treatment

Aim: To evaluate the effectiveness of low-intensity focused ultrasound (LIFU) therapy in the management of cancer-related neuropathic pain (CNP). Methods: A retrospective review with 22 patients with CNP treated with LIFU therapy (frequency 3 Hz, 3 W/cm2, pulse mode duty cycle 50%) was conducted. Results: Out of the 22 patients, 15 had CNP secondary to chemotherapy-induced peripheral neuropathy. Compared with baseline, there was a significant reduction in numeric pain rating scale (p < 0.001). Additionally, 76.5% of patients (n = 13) were considered to be responders to LIFU therapy. Conclusion: LIFU therapy may be a viable treatment modality in the management of CNP, specifically chemotherapy-induced peripheral neuropathy, with a minimal side effect profile. Larger, prospective studies with a structured protocol are necessary.

The Regulation of Bone Morphogenetic Protein/Smads Signaling Pathway in Spinal Cord Injury

2020 ◽  
Vol 10 (3) ◽  
pp. 323-328
Author(s):  
Zhigang Zhou ◽  
Kai Cao ◽  
Jianping Liao ◽  
Song Zhou ◽  
Liangliang Zhou ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Treatment Group ◽  
Signaling Pathway ◽  
Rating Scale ◽  
Enzyme Linked Immunosorbent Assay ◽  
Control Group ◽  
Spinal Cord Tissue ◽  
Cord Injury ◽  
Smad5 Mrna

The incidence of spinal cord injury (SCI) increases year by year. SCI is characterized as high disability rate and poor prognosis. BMP/Smads signaling participates in the formation of osteoblasts and renal failure. This article will explore the regulation of BMP/Smads signaling pathway in SCI. Wistar rats were divided into control group; SCI group; and BMP-2 treatment group that were treated by tail vein injection of BMP-2 antisense oligonucleotide BMP-2 phosphorothioate AODN at 30 min after modeling. Real-time PCR and Western blot were used to detect BMP-2, Smad1, and Smad5 expressions. Hematoxylin-eosin (HE) staining was applied to analyze the change of SCI in each group. Immunohistochemistry (IHC) was selected to test BMPR Ia expression. Basso, Beattie Bresnahan-cocomotor rating scale (BBB) scale and Reuter score were compared. Enzyme-linked immunosorbent assay (ELISA) was adopted to detect TNF-α and Interleukin-2 (IL-2) expressions. Compared with the control group, BMP-2, Smad1, and Smad5 mRNA and protein expressions increased, BBB score declined, Reuter score elevated, and TNF-α and IL-2 secretion enhanced in the SCI group (P < 0.05). HE staining showed spinal cord injury, and IHC exhibited increased expression of BMPR Ia. The TGF-β treatment group significantly reduced the expressions of BMP-2, Smad1, and Smad5 mRNA and protein, increased BBB score, reduced Reuter score, and weakened the secretions of TNF-α and IL-2 (P < 0.05). HE staining demonstrated decreased reduction of spinal cord tissue and declined expression of BMPR Ia. SCI activated BMP/Smads signaling pathway, up-regulated BMPR Ia expression, and promoted inflammation. Regulation of BMP/Smads signaling pathway can downregulate BMPR Ia expression and inhibit inflammation to effectively relieve SCI.

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