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1.
Lasers Med Sci ; 39(1): 143, 2024 May 28.
Article in English | MEDLINE | ID: mdl-38806837

ABSTRACT

The purpose of this study is to explore the potential application of photobiomodulation to irritable bowel syndrome. We established the following experimental groups: the Non-Stress + Sham group, which consisted of rats that were not restrained and were only subjected to sham irradiation; the Stress + Sham group, which underwent 1 hour of restraint stress followed by sham irradiation; and the Stress + Laser group, which was subjected to restraint stress and percutaneous laser irradiation bilaterally on the L6 dorsal root ganglia for 5 minutes each. The experiment was conducted twice, with three and two laser conditions examined. Following laser irradiation, a barostat catheter was inserted into the rat's colon. After a 30-minute acclimatization period, the catheter was inflated to a pressure of 60 mmHg, and the number of abdominal muscle contractions was measured over a 5-minute period. The results showed that photobiomodulation significantly suppressed the number of abdominal muscle contractions at average powers of 460, 70, and 18 mW. However, no significant suppression was observed at average powers of 1 W and 3.5 mW. This study suggests that photobiomodulation can alleviate visceral hyperalgesia induced by restraint stress, indicating its potential applicability to irritable bowel syndrome.


Subject(s)
Hyperalgesia , Irritable Bowel Syndrome , Low-Level Light Therapy , Rats, Sprague-Dawley , Restraint, Physical , Animals , Low-Level Light Therapy/methods , Rats , Hyperalgesia/radiotherapy , Hyperalgesia/etiology , Male , Irritable Bowel Syndrome/radiotherapy , Irritable Bowel Syndrome/therapy , Stress, Psychological , Muscle Contraction/radiation effects , Abdominal Muscles/radiation effects , Disease Models, Animal
2.
Sci Rep ; 11(1): 6322, 2021 03 18.
Article in English | MEDLINE | ID: mdl-33737659

ABSTRACT

During voluntary contractions, corticomuscular coherence (CMC) is thought to reflect a mutual interaction between cortical and muscle oscillatory activities, respectively measured by electroencephalography (EEG) and electromyography (EMG). However, it remains unclear whether CMC modulation would depend on the contribution of neural mechanisms acting at the spinal level. To this purpose, modulations of CMC were compared during submaximal isometric, shortening and lengthening contractions of the soleus (SOL) and the medial gastrocnemius (MG) with a concurrent analysis of changes in spinal excitability that may be reduced during lengthening contractions. Submaximal contractions intensity was set at 50% of the maximal SOL EMG activity. CMC was computed in the time-frequency domain between the Cz EEG electrode signal and the unrectified SOL or MG EMG signal. Spinal excitability was quantified through normalized Hoffmann (H) reflex amplitude. The results indicate that beta-band CMC and normalized H-reflex were significantly lower in SOL during lengthening compared with isometric contractions, but were similar in MG for all three muscle contraction types. Collectively, these results highlight an effect of contraction type on beta-band CMC, although it may differ between agonist synergist muscles. These novel findings also provide new evidence that beta-band CMC modulation may involve spinal regulatory mechanisms.


Subject(s)
Motor Cortex/physiology , Muscle Contraction/physiology , Muscle, Skeletal/physiology , Spinal Cord/physiology , Adult , Electric Stimulation , Electroencephalography , Electromyography , Evoked Potentials, Motor/physiology , Evoked Potentials, Motor/radiation effects , Female , H-Reflex/physiology , H-Reflex/radiation effects , Humans , Isometric Contraction/physiology , Isometric Contraction/radiation effects , Male , Motor Cortex/diagnostic imaging , Motor Cortex/radiation effects , Muscle Contraction/radiation effects , Muscle, Skeletal/diagnostic imaging , Muscle, Skeletal/radiation effects , Torque
3.
Sci Rep ; 11(1): 6399, 2021 03 18.
Article in English | MEDLINE | ID: mdl-33737664

ABSTRACT

The effectiveness of neuromuscular electrical stimulation (NMES) for rehabilitation is proportional to the evoked torque. The progressive increase in torque (extra torque) that may develop in response to low intensity wide-pulse high-frequency (WPHF) NMES holds great promise for rehabilitation as it overcomes the main limitation of NMES, namely discomfort. WPHF NMES extra torque is thought to result from reflexively recruited motor units at the spinal level. However, whether WPHF NMES evoked force can be modulated is unknown. Therefore, we examined the effect of two interventions known to change the state of spinal circuitry in opposite ways on evoked torque and motor unit recruitment by WPHF NMES. The interventions were high-frequency transcutaneous electrical nerve stimulation (TENS) and anodal transcutaneous spinal direct current stimulation (tsDCS). We show that TENS performed before a bout of WPHF NMES results in lower evoked torque (median change in torque time-integral: - 56%) indicating that WPHF NMES-evoked torque might be modulated. In contrast, the anodal tsDCS protocol used had no effect on any measured parameter. Our results demonstrate that WPHF NMES extra torque can be modulated and although the TENS intervention blunted extra torque production, the finding that central contribution to WPHF NMES-evoked torques can be modulated opens new avenues for designing interventions to enhance WPHF NMES.


Subject(s)
Electric Stimulation/methods , Isometric Contraction/physiology , Muscle, Skeletal/physiology , Transcutaneous Electric Nerve Stimulation/methods , Adult , Female , Humans , Male , Muscle Contraction/physiology , Muscle Contraction/radiation effects , Muscle Fatigue/physiology , Muscle Fatigue/radiation effects , Muscle, Skeletal/radiation effects
4.
Lasers Med Sci ; 35(8): 1751-1758, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32337679

ABSTRACT

Complete or incomplete spinal cord injury (SCI) results in permanent neurological deficits due to the interruption of nerve impulses, causing the loss of motor and sensory function, which leads to a reduction in quality of life. The focus of rehabilitation for such individuals is to improve quality of life and promote functional recovery. Photobiomodulation (PBM) has proved to be promising complementary treatment in cases of SCI. The aim of the present study was to investigate the effects of PBM combined with physiotherapy on sensory-motor responses below the level of the injury and quality of life in individuals with SCI. Thirty participants were randomized for allocation to the PBM group (active PBM + physiotherapy) or sham group (sham PBM + physiotherapy). Physiotherapy was administered three times a week. Sensitivity and motor skills were evaluated using the ASIA impairment scale. Quality of life was assessed using the WHOQOL-BREF questionnaire. The data were analyzed with the level of significance set to 5%. Improvements in sensitivity and an increase in the perception of muscle contraction were found in the active PBM group 30 days after treatment compared with the sham group. The results of the WHOQOL-BREF questionnaire revealed a significant difference in general quality of life favoring the active PBM group over the sham group after treatment. Physiotherapy combined with PBM leads to better sensory-motor recovery in patients with SCI as well as a better perception of health and quality of life. Trial registration identifier: NCT03031223.


Subject(s)
Low-Level Light Therapy , Motor Activity/radiation effects , Physical Therapy Modalities , Sensation/radiation effects , Spinal Cord Injuries/physiopathology , Spinal Cord Injuries/therapy , Adult , Female , Humans , Male , Middle Aged , Muscle Contraction/radiation effects , Quality of Life , Recovery of Function/radiation effects , Spinal Cord Injuries/radiotherapy , Young Adult
5.
Kaohsiung J Med Sci ; 35(11): 702-707, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31390143

ABSTRACT

Low-level laser therapy (LLLT) applying on knee osteoarthritis (OA) patients has shown positive outcomes in analgesic effect and functional recovery. However, few studies applied such therapy on large area of quadriceps muscle in these patients. The aim of this study was to evaluate immediate effect of multi-focal LLLT on quadriceps of knee OA patients in pain and functional performance. Fifty-one participants with knee OA were enrolled and evaluated before (T1) and immediately after intervention (T2) by knee joint pain in numeric rating scale (NRS), walking speed, timed five-chair stands, and quadriceps strength by isokinetic dynamometer. Intervention with two multi-focal Gallium-Aluminum-Arsenide laser devices, each device with 36 laser diodes (wavelength 808 ± 10 nm, continuous, mean power 50 mW, 30 minutes), applied simultaneously over bilateral quadriceps with a total dose of 180 J for each thigh. The multi-focal LLLT significantly improved knee joint pain as measured by the NRS (54% reduction), timed five-chair stands, and walking speed (P < .05). Knee extensor strength also increased in terms of peak torque and force of concentric and eccentric contraction as measured by isokinetic dynamometer (P < .05). In conclusion, single-session multi-focal LLLT on quadriceps in knee OA patients has immediate beneficial effect on knee pain reduction, quadriceps strengthening and functional performance recovery. Long-term effect requires further investigation. Multi-focal LLLT on quadriceps might serve as an alternative non-invasive treatment option in these patients.


Subject(s)
Low-Level Light Therapy , Osteoarthritis, Knee/radiotherapy , Quadriceps Muscle/pathology , Quadriceps Muscle/radiation effects , Aged , Female , Humans , Male , Muscle Contraction/radiation effects , Osteoarthritis, Knee/physiopathology , Pain/etiology , Quadriceps Muscle/physiopathology , Treatment Outcome
6.
Sci Rep ; 9(1): 8042, 2019 07 08.
Article in English | MEDLINE | ID: mdl-31285453

ABSTRACT

Development of bio-microactuators combining microdevices and cellular mechanical functions has been an active research field owing to their desirable properties including high mechanical integrity and biocompatibility. Although various types of devices were reported, the use of as-is natural muscle tissue should be more effective. An earthworm muscle-driven valve has been created. Long-time (more than 2 min) and repeatable displacement was observed by chemical (acetylcholine) stimulation. The generated force of the muscle (1 cm × 3 cm) was 1.57 mN on average for 2 min by the acetylcholine solution (100 mM) stimulation. We demonstrated an on-chip valve that stopped the constant pressure flow by the muscle contraction. For electrical control, short pulse stimulation was used for the continuous and repeatable muscle contraction. The response time was 3 s, and the pressure resistance was 3.0 kPa. Chemical stimulation was then used for continuous muscle contraction. The response time was 42 s, and the pressure resistance was 1.5 kPa. The ON (closed) state was kept for at least 2 min. An on-chip valve was demonstrated that stopped the constant pressure flow by the muscle contraction. This is the first demonstration of the muscle-based valve that is 100% chemically actuated and controlled.


Subject(s)
Acetylcholine/chemistry , Electric Stimulation , Oligochaeta/physiology , Animals , Electricity , Mechanical Phenomena/radiation effects , Muscle Contraction/drug effects , Muscle Contraction/radiation effects , Muscle, Smooth/chemistry , Muscles/chemistry , Oligochaeta/chemistry , Trachea/chemistry , Trachea/drug effects
7.
PLoS One ; 14(6): e0217985, 2019.
Article in English | MEDLINE | ID: mdl-31216311

ABSTRACT

OBJECTIVE: Segmented deep brain stimulation leads in the subthalamic nucleus have shown to increase therapeutic window using directional stimulation. However, it is not fully understood how these segmented leads with reduced electrode size modify the volume of tissue activated (VTA) and how this in turn relates with clinically observed therapeutic and side effect currents. Here, we investigated the differences between directional and omnidirectional stimulation and associated VTAs with patient-specific therapeutic and side effect currents for the two stimulation modes. APPROACH: Nine patients with Parkinson's disease underwent DBS implantation in the subthalamic nucleus. Therapeutic and side effect currents were identified intraoperatively with a segmented lead using directional and omnidirectional stimulation (these current thresholds were assessed in a blinded fashion). The electric field around the lead was simulated with a finite-element model for a range of stimulation currents for both stimulation modes. VTAs were estimated from the electric field by numerical differentiation and thresholding. Then for each patient, the VTAs for given therapeutic and side effect currents were projected onto the patient-specific subthalamic nucleus and lead position. RESULTS: Stimulation with segmented leads with reduced electrode size was associated with a significant reduction of VTA and a significant increase of radial distance in the best direction of stimulation. While beneficial effects were associated with activation volumes confined within the anatomical boundaries of the subthalamic nucleus at therapeutic currents, side effects were associated with activation volumes spreading beyond the nucleus' boundaries. SIGNIFICANCE: The clinical benefits of segmented leads are likely to be obtained by a VTA confined within the subthalamic nucleus and a larger radial distance in the best stimulation direction, while steering the VTA away from unwanted fiber tracts outside the nucleus. Applying the same concepts at a larger scale and in chronically implanted patients may help to predict the best stimulation area.


Subject(s)
Deep Brain Stimulation/methods , Parkinson Disease/therapy , Subthalamic Nucleus/radiation effects , Adult , Aged , Central Nervous System/physiopathology , Central Nervous System/radiation effects , Deep Brain Stimulation/adverse effects , Electric Stimulation , Electrodes, Implanted , Electromagnetic Fields/adverse effects , Female , Humans , Male , Middle Aged , Muscle Contraction/radiation effects , Parkinson Disease/physiopathology , Subthalamic Nucleus/physiopathology
8.
Adv Healthc Mater ; 8(13): e1900198, 2019 07.
Article in English | MEDLINE | ID: mdl-31066237

ABSTRACT

The use of light for triggering skeletal and cardiac muscles allows lower invasiveness higher selectivity and unprecedented possibility to target individual cells or even subcellular compartments in a temporally and spatially precise manner. Because cells are in general transparent, this requires the development of suitable interfaces that bestow light sensitivity to living matter. In the present work, successfully demonstrated is the use of conjugated polymer films as transducer to optically enhance the contraction rate of a human and patient-specific cardiac in vitro cell model. By different experimental approaches, the coupling mechanism to the photothermal effect is assigned. This work extends the range of application of the polymer-mediated cell photostimulation phenomenon to cardiac muscle cells, opening up possible applications in cardiac therapy and for implementation of in vitro studies.


Subject(s)
Induced Pluripotent Stem Cells/cytology , Myocytes, Cardiac/metabolism , Polymers/chemistry , Biocompatible Materials/chemistry , Cell Differentiation , Cell Survival/drug effects , Cellular Reprogramming , Glass/chemistry , Humans , Induced Pluripotent Stem Cells/metabolism , Light , Muscle Contraction/drug effects , Muscle Contraction/radiation effects , Myocytes, Cardiac/cytology , Myocytes, Cardiac/radiation effects , Polymers/pharmacology , Temperature
10.
Folia Med (Plovdiv) ; 61(3): 411-418, 2019 09 30.
Article in English | MEDLINE | ID: mdl-32337928

ABSTRACT

BACKGROUND: Besides its "classical" neurotransmitter function in the central and peripheral nervous systems, serotonin, or 5-hydroxytryptamine (5-HT) is also a local hormone in a number of tissues, including those of the GI tract. Radiation is known to be able to disrupt certain functions of the tract, modulated by 5-HT-signaling pathways, or the serotonin receptors themselves. AIM: The present investigation focused on clarifying the nature and extent of influence of an accelerated electron beam with energy of 9 MeV on the serotonergic mediation of healthy smooth muscle gastric tissue of rats following total body irradiation of the animals. MATERIALS AND METHODS: The study involved a control group and two experimental groups of animals exposed to 1 and 5 Gy, respectively, using Siemens Primus S/N 3561. Circular smooth muscle tissues were isolated from rats 1 hour and 18 hours after they were exposed to 1 and 5 Gy and also 5 days after irradiation from the rats that received a dose of 5 Gy in order to investigate the action of exogenous serotonin at increasing concentrations from 10-8 to 10-4 mol/l. The contractile reactivity of each group SM preparations was registered isometrically. RESULTS: Electron beams with energy of 9 MeV did not damage the contractile apparatus of gastric SM of rats and had a stimulating effect on contractility resulting from rapidly developing processes (1 hour) or later occurring once (5 days). CONCLUSIONS: Difference was observed in the importance of the factors of received dose, lapse of time from irradiation to investigation of SM tissues, and exogenous 5-HT concentration for the changes in SM reactivity in serotonin-induced tonic and phasic responses.


Subject(s)
Electrons , Muscle Contraction/radiation effects , Muscle, Smooth/radiation effects , Serotonin/pharmacology , Whole-Body Irradiation , Animals , Male , Muscle Contraction/drug effects , Muscle, Smooth/drug effects , Rats , Rats, Wistar
11.
Lasers Med Sci ; 34(1): 191-199, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30443882

ABSTRACT

Sepsis is a big health problem and one of the most common causes of acute lung injury (ALI) leading to high mortality. Pro-resolving mediators play an important role in abrogating the inflammation and promoting tissue homeostasis restoration. ALI treatment is still a clinical health problem, so new therapies are needed. Here, we evaluated the effect of photobiomodulation treatment on the resolution process of ALI induced by lipopolysaccharide (LPS). Male Balb/c mice were submitted to LPS (ip) or vehicle and irradiated or not with light emitting diode (LED) 2 and 6 h after LPS or vehicle injection, and the parameters were investigated 3 and 7 days after the injections. Our results showed that after 3 days of LED treatment the blood and bronchoalveolar lavage (BAL) cells as well as interleukins (IL) including IL-6 and IL-17 were reduced. No differences were observed in the bone marrow cells, tracheal reactivity, and lipoxin A4 and resolvin E2. Indeed, after 7 days of LED treatment the bone marrow cells, lymphocytes, and lipoxin A4 were increased, while IL-6, IL-17, and IL-10 were decreased. No differences were observed in the blood cells and tracheal reactivity. Thus, our results showed that LED treatment attenuated ALI induced by sepsis by modulating the cell mobilization from their reserve compartments. In addition, we also showed later effects of the LED up to 7 days after the treatment. This study proposes photobiomodulation as therapeutic adjuvant to treat ALI.


Subject(s)
Acute Lung Injury/etiology , Acute Lung Injury/radiotherapy , Inflammation/radiotherapy , Low-Level Light Therapy , Sepsis/complications , Animals , Bone Marrow/pathology , Bone Marrow/radiation effects , Bronchoalveolar Lavage , Cell Movement/radiation effects , Cholinergic Agents/pharmacology , Cytokines/metabolism , Eicosapentaenoic Acid/analogs & derivatives , Eicosapentaenoic Acid/metabolism , Inflammation/pathology , Lipopolysaccharides , Lipoxins/metabolism , Lung/pathology , Lung/radiation effects , Male , Mice, Inbred BALB C , Muscle Contraction/radiation effects , Muscle, Smooth/physiopathology , Muscle, Smooth/radiation effects
12.
PLoS One ; 13(12): e0209513, 2018.
Article in English | MEDLINE | ID: mdl-30586389

ABSTRACT

Previous studies investigating the effects of transcranial direct current stimulation (tDCS) on muscle strength showed no consensus. Therefore, the purpose of this article was to systematically review the literature on the effects of single dose tDCS to improve muscle strength. A systematic literature search was conducted on PubMeb, ISI Web of Science, SciELO, and Scopus using search terms regarding tDCS and muscle strength. Studies were included in accordance with Population, Intervention, Comparison, Outcomes, and Setting (PICOS) including criteria. Healthy men and women, strength training practitioners or sedentary were selected. The acute effects of single dose anode stimulus of tDCS (a-tDCS) and the placebo stimulus of tDCS (sham) or no interventions were considered as an intervention and comparators, respectively. Measures related to muscle strength were analyzed. To conduct the analyses a weighted mean difference (WMD) and the standardized mean difference (SMD) were applied as appropriate. A total of 15 studies were included in this systematic review and 14 in meta-analysis. Regarding the maximal isometric voluntary contraction (MIVC), a small effect was seen between tDCS and Sham with significant difference between the conditions (SMD = 0.29; CI95% = 0.05 to 0.54; Z = 2.36; p = 0.02). The muscular endurance measured by the seconds sustaining a percentage of MIVC demonstrated a large effect between tDCS and Sham (WMD = 43.66; CI95% = 29.76 to 57.55; Z = 6.16; p < 0.001), showing an improvement in muscular endurance after exposure to tDCS. However, muscular endurance based on total work showed a trivial effect between tDCS and Sham with no significant difference (SMD = 0.22; CI95% = -0.11 to 0.54; Z = 1.32, p = 0.19). This study suggests that the use of tDCS may promote increase in maximal voluntary contraction and muscular endurance through isometric contractions.


Subject(s)
Elbow/physiology , Knee/physiology , Muscle Strength/physiology , Transcranial Direct Current Stimulation/methods , Female , Humans , Isometric Contraction/radiation effects , Male , Muscle Contraction/physiology , Muscle Contraction/radiation effects , Muscle Strength/radiation effects , Resistance Training
13.
Technol Cancer Res Treat ; 17: 1533033818788078, 2018 01 01.
Article in English | MEDLINE | ID: mdl-30012058

ABSTRACT

We studied the influence of various parameters of high-frequency nanosecond pulse bursts on the strength of rabbit muscle contractions. Ten unipolar high-frequency pulse bursts with various field intensities E (1 kV/cm, 4 kV/cm, and 8 kV/cm), intraburst frequencies f (10 kHz, 100 kHz, and 1 MHz), and intraburst pulse numbers N (1, 10, and 100) were applied using a pair of plate electrodes to the surface skin of the rabbits' biceps femoris, and the acceleration signal of muscle contraction near the electrode was measured using a 3-axis acceleration sensor. A time- and frequency-domain analysis of the acceleration signals showed that the peak value of the signal increases with the increasing strength of the pulse burst and that the frequency spectra of the signals measured under various pulse bursts have characteristic frequencies (at approximately 2 Hz, 32 Hz, 45 Hz, and 55 Hz). Furthermore, we processed the data through multivariate nonlinear regression analysis and variance analysis and determined that the peak value of the signal scales with the logarithm to the base 10 of EN x, where x is a value that scales with the logarithm to the base 10 of intraburst frequency (f). These results indicate that for high-frequency nanosecond pulse treatment of solid tumors in or near muscles, when the field strength is relatively high, the intraburst frequency and the intraburst pulse number require appropriate selection to limit the strength of muscle contraction as much as possible.


Subject(s)
Electromagnetic Fields/adverse effects , Muscle Contraction/radiation effects , Neoplasms/radiotherapy , Animals , Disease Models, Animal , Humans , Neoplasms/pathology , Rabbits
14.
Biosci Rep ; 38(3)2018 06 29.
Article in English | MEDLINE | ID: mdl-29654166

ABSTRACT

Skeletal muscle fatigue and post-exertional malaise are key symptoms of myalgic encephalomyelitis (ME)/chronic fatigue syndrome (ME/CFS). We have previously shown that AMP-activated protein kinase (AMPK) activation and glucose uptake are impaired in primary human skeletal muscle cell cultures derived from patients with ME/CFS in response to electrical pulse stimulation (EPS), a method which induces contraction of muscle cells in vitro The aim of the present study was to assess if AMPK could be activated pharmacologically in ME/CFS. Primary skeletal muscle cell cultures from patients with ME/CFS and healthy controls were treated with either metformin or compound 991. AMPK activation was assessed by Western blot and glucose uptake measured. Both metformin and 991 treatment significantly increased AMPK activation and glucose uptake in muscle cell cultures from both controls and ME/CFS. Cellular ATP content was unaffected by treatment although ATP content was significantly decreased in ME/CFS compared with controls. Pharmacological activation of AMPK can improve glucose uptake in muscle cell cultures from patients with ME/CFS. This suggests that the failure of EPS to activate AMPK in these muscle cultures is due to a defect proximal to AMPK. Further work is required to delineate the defect and determine whether pharmacological activation of AMPK improves muscle function in patients with ME/CFS.


Subject(s)
Fatigue Syndrome, Chronic/drug therapy , Muscle Contraction/radiation effects , Muscle, Skeletal/metabolism , Protein Kinases/genetics , AMP-Activated Protein Kinase Kinases , Adult , Biopsy , Carbohydrate Metabolism/drug effects , Carbohydrate Metabolism/radiation effects , Cell Culture Techniques , Electric Stimulation , Fatigue Syndrome, Chronic/physiopathology , Female , Glucose/metabolism , Humans , Male , Metformin/pharmacology , Muscle Contraction/drug effects , Muscle, Skeletal/drug effects , Muscle, Skeletal/pathology , Muscle, Skeletal/radiation effects , Protein Kinases/radiation effects
15.
Biol Pharm Bull ; 41(3): 368-373, 2018.
Article in English | MEDLINE | ID: mdl-29491213

ABSTRACT

A digitization approach to the time course of radiation-induced mouse leg contracture was proposed for quantifying the radiation effect on an individual living mouse. The shortening of the mouse leg length can be easily measured with a caliper/ruler to offer a very simple digitalized index of the radiation effect. Left hind legs of mice were irradiated with single dose of 32 Gy of 290 MeV carbon-ion beam using 0, 50, or 117 mm binary filter (BF). The right legs were used as a control. The lengths of both hind legs of the mice were measured using a digital caliper before irradiation and every week after irradiation. The degree of leg contracture, ΔSt, at the time point t was estimated by subtraction of the left irradiated leg length from the right control leg length. Equation was fitted on the daily time course of ΔSt, and two parameters, ΔSmax and Ts, were estimated. ΔSt=ΔSmax×(1-exp(t/Ts)), where ΔSmax is the maximum degree of leg contracture, and Ts is time of leg contracture. The effect of carbon-ion irradiation on a living mouse was quantified by ΔSmax and Ts of the leg contracture, and then compared to that of X-rays. By 32 Gy irradiation, ΔSmax was largest for the BF117 experiment, followed by X-ray~BF50>BF0. Ts was shortest for the BF50 experiment, while other irradiation conditions give similar Ts. A logarithmic function was successfully repurposed for the evaluation of radio-biological response.


Subject(s)
Hindlimb/anatomy & histology , Muscle Contraction/drug effects , Muscle Contraction/radiation effects , Muscle, Skeletal/drug effects , Muscle, Skeletal/radiation effects , Algorithms , Animals , Carbon , Female , Gamma Rays , Heavy Ions , Mice , Mice, Inbred C3H , Muscle, Skeletal/anatomy & histology , X-Rays
16.
PLoS One ; 13(3): e0193923, 2018.
Article in English | MEDLINE | ID: mdl-29513744

ABSTRACT

Radiation-induced bladder toxicity is associated with radiation therapy for pelvic malignancies, arising from unavoidable irradiation of neighbouring normal bladder tissue. This study aimed to investigate the acute impact of ionizing radiation on the contractility of bladder strips and identify the radiation-sensitivity of the mucosa vs the detrusor. Guinea-pig bladder strips (intact or mucosa-free) received ex vivo sham or 20Gy irradiation and were studied with in vitro myography, electrical field stimulation and Ca2+-fluorescence imaging. Frequency-dependent, neurogenic contractions in intact strips were reduced by irradiation across the force-frequency graph. The radiation-difference persisted in atropine (1µM); subsequent addition of PPADs (100µM) blocked the radiation effect at higher stimulation frequencies and decreased the force-frequency plot. Conversely, neurogenic contractions in mucosa-free strips were radiation-insensitive. Radiation did not affect agonist-evoked contractions (1µM carbachol, 5mM ATP) in intact or mucosa-free strips. Interestingly, agonist-evoked contractions were larger in irradiated mucosa-free strips vs irradiated intact strips suggesting that radiation may have unmasked an inhibitory mucosal element. Spontaneous activity was larger in control intact vs mucosa-free preparations; this difference was absent in irradiated strips. Spontaneous Ca2+-transients in smooth muscle cells within tissue preparations were reduced by radiation. Radiation affected neurogenic and agonist-evoked bladder contractions and also reduced Ca2+-signalling events in smooth muscle cells when the mucosal layer was present. Radiation eliminated a positive modulatory effect on spontaneous activity by the mucosa layer. Overall, the findings suggest that radiation impairs contractility via mucosal regulatory mechanisms independent of the development of radiation cystitis.


Subject(s)
Muscle, Smooth/radiation effects , Urinary Bladder/radiation effects , Adenosine Triphosphate/pharmacology , Animals , Atropine/pharmacology , Calcium Signaling , Carbachol/pharmacology , Dose-Response Relationship, Radiation , Guinea Pigs , In Vitro Techniques , Male , Mucous Membrane/drug effects , Mucous Membrane/physiology , Muscle Contraction/drug effects , Muscle Contraction/radiation effects , Muscle, Smooth/drug effects , Muscle, Smooth/physiology , Radiation Dosage , Urinary Bladder/drug effects
17.
Adv Med Sci ; 63(1): 64-67, 2018 Mar.
Article in English | MEDLINE | ID: mdl-28822265

ABSTRACT

PURPOSE: The mechanism of action of low level laser irradiation on tissues is unclear. Authors of publications present the positive clinical impact of low and medium power laser irradiation on vascular reactivity. The purpose of this study was to analyze the role of vascular endothelium in laser-induced constricted by endothelin-1 and phenylephrine. MATERIALS AND METHODS: Experiments were performed on isolated and perfused rat tail arteries of weighing 250-350g male Wistar rats. Contractility of arteries as a response to endothelin-1 and phenylephrine was measured after exposure to laser stimulation (10, 30 and 110mW). RESULTS: Laser irradiation inhibits vascular smooth muscle contraction induced by endothelin-1 and an alpha-adrenergic receptor agonist, phenylephrine proportionally to the laser power. Concentration-response curves were shifted to the right with significant reduction in maximal response. Laser irradiation at the power of 10mW, 30mW, and 110mW reduced the maximum response of arteries stimulated with phenylephrine sequentially to 88%, 72%, and 52%. Similar findings were observed during stimulation of endothelin-1. Laser irradiation at the power of 10mW, 30mW and 110mW resulted in maximal response respectively reduced to 94%, 62% and 38%. CONCLUSION: Our results strongly suggest that during low level laser irradiation vascular smooth muscle cells reactivity is reduced, this effect is present in arteries with normal endothelium. The mechanism of action of laser biosimulation on tissues is unclear. Authors of publications present the positive clinical impact of low level laser irradiation on vascular reactivity.


Subject(s)
Arteries/physiology , Arteries/radiation effects , Low-Level Light Therapy , Animals , Arteries/drug effects , Endothelin-1/metabolism , Muscle Contraction/drug effects , Muscle Contraction/radiation effects , Perfusion , Phenylephrine/pharmacology , Pressure , Rats, Wistar
18.
Environ Toxicol Pharmacol ; 54: 177-183, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28755625

ABSTRACT

INTRODUCTION: It is well known that moderate to high doses of ionizing radiation have a toxic effect on the organism. However, there are few experimental studies on the mechanisms of LDR ionizing radiation on nerve regeneration after peripheral nerve injury. METHODS: We established the rats' peripheral nerve injury model via repaired Peripheral nerve injury nerve, vascular endothelial growth factor a and Growth associated protein-43 were detected from different treatment groups. We performed transcriptome sequencing focusing on investigating the differentially expressed genes and gene functions between the control group and 1Gy group. Sequencing was done by using high-throughput RNA-sequencing (RNA-seq) technologies. RESULTS: The results showed the 1Gy group to be the most effective promoting repair. RNA-sequencing identified 619 differently expressed genes between control and treated groups. A Gene Ontology analysis of the differentially expressed genes revealed enrichment in the functional pathways. Among them, candidate genes associated with nerve repair were identified. DISCUSSION: Pathways involved in cell-substrate adhesion, vascular smooth muscle contraction and cell adhesion molecule signaling may be involved in recovery from peripheral nerve injury.


Subject(s)
Muscle Contraction/radiation effects , Muscle, Smooth, Vascular/radiation effects , Peripheral Nerve Injuries/radiotherapy , Animals , GAP-43 Protein/genetics , GAP-43 Protein/metabolism , Gene Expression Regulation/radiation effects , Male , Peripheral Nerve Injuries/metabolism , Peripheral Nerve Injuries/physiopathology , Rats, Sprague-Dawley , Signal Transduction/radiation effects , Transcriptome/radiation effects , Vascular Endothelial Growth Factor A/genetics , Vascular Endothelial Growth Factor A/metabolism , X-Rays
19.
BJU Int ; 120(5): 724-730, 2017 11.
Article in English | MEDLINE | ID: mdl-28609582

ABSTRACT

OBJECTIVES: To measure the effect of external heating on bladder wall contractile function, histological structure and expression of proteins related to tissue protection and apoptosis. MATERIAL AND METHODS: In vitro preparations of bladder wall and ex vivo perfused pig bladders were heated from 37 to 42°C, 46 and 50°C for 15 min. Isolated preparations were heated by radiant energy and perfused bladders were heated by altering perfusate temperature. Spontaneous contractions or pressure variations were recorded, as well as responses to the muscarinic agonist carbachol or motor nerve excitation in vitro during heating. Tissue histology in control and after heating was analysed using haematoxylin and eosin staining and 4'-6-diamidino-2-phenylindole (DAPI) nuclear labelling. The effects of heating on protein expression levels of (i) heat shock proteins HSP27-pSer82 and inducible-HSP70 and (ii) caspase-3 and its downstream DNA-repair substrate poly-[ADP-ribose] polymerase (PARP) were measured. RESULTS: Heating to 42°C reduced spontaneous contractions or pressure variations by ~70%; effects were fully reversible. There were no effects on carbachol or nerve-mediated responses. Tissue histology was unaffected by heating, and expression of heat shock proteins as well as caspase-3 and PARP were also unaltered. A TRPV1 antagonist had no effect on the reduction of spontaneous activity. Heating to 46°C had a similar effect on spontaneous activity and also reduced the carbachol contracture. Urothelial structure was damaged, caspase-3 levels were increased and inducible-HSP70 levels declined. At 50°C evoked contractions were abolished, the urothelium was absent and heat shock proteins and PARP expression was reduced with raised caspase-3 expression. CONCLUSIONS: Heating to 42°C caused a profound, reversible and reproducible attenuation of spontaneous activity, with no tissue damage and no initiation of apoptosis pathways. Higher temperatures caused tissue damage and activation of apoptotic mechanisms. Mild heating offers a novel approach to reducing bladder spontaneous activity.


Subject(s)
Muscle Contraction/radiation effects , Urinary Bladder/physiology , Urinary Bladder/radiation effects , Animals , Female , Hot Temperature , Male , Muscle Contraction/physiology , Proteins/analysis , Proteins/metabolism , Swine , Urinary Bladder/metabolism
20.
J Biophotonics ; 10(12): 1683-1693, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28417574

ABSTRACT

Since asthma is a multifactorial disease where treatment sometimes is not effective, new therapies that improve the respiratory discomfort of patients are of great importance. Phototherapy as Light-emitting diode (LED) has emerged as a treatment that presents good results for diseases that are characterized by inflammation. Thus, our objective was to investigate the effects of LED on lung inflammation, by an evaluation of lung cell infiltration, mucus secretion, oedema, and the production of cytokines. Male Balb/c mice were or not sensitized and challenged with ovalbumin (OVA) and treated or not with LED therapy (1 h and 4 h after each OVA challenge). Twenty-four hours after the last OVA challenge, analyzes were performed. Our results showed that LED treatment in asthmatic mice reduced the lung cell infiltration, the mucus production, the oedema, and the tracheal's contractile response. It also increased the IL-10 and the IFN-gamma levels. The effects of LED treatment on lung inflammation may be modulated by IL-10, IFN-gamma, and by mast cells. This study may provide important information about the effects of LED, and in addition, it may open the possibility of a new approach for the treatment of asthma.


Subject(s)
Asthma/chemically induced , Asthma/complications , Ovalbumin/adverse effects , Phototherapy/instrumentation , Pneumonia/complications , Pneumonia/therapy , Animals , Bronchoalveolar Lavage Fluid , Cell Count , Cytokines/metabolism , Disease Models, Animal , Granulocytes/immunology , Granulocytes/radiation effects , Lymphocytes/immunology , Lymphocytes/radiation effects , Macrophages/immunology , Macrophages/radiation effects , Male , Mast Cells/metabolism , Mast Cells/radiation effects , Mice , Mice, Inbred BALB C , Muscle Contraction/radiation effects , Pneumonia/immunology , Pneumonia/physiopathology , Trachea/physiopathology , Trachea/radiation effects
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