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1.
J Formos Med Assoc ; 115(9): 703-13, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26386674

RESUMO

BACKGROUND/PURPOSE: Few studies have investigated the feasibility of using pudendal neuromodulation to regulate bladder function in spinal cord-injured (SCI) animals. The present study aimed to determine the effects of electrical activation of the pudendal sensory branch on improving voiding functions in rats 6 weeks after a spinal cord injury and to explore the underlying neuromodulatory mechanisms. METHODS: Two urodynamic measurements were used to assess the effects of electrical stimulation (ES) on bladder and urethral functions: simultaneous recordings of the intravesical pressure (IVP) during continuous isotonic transvesical infusion (i.e., isotonic IVP) and external urethral sphincter (EUS) electromyography (EUS-EMG), and simultaneous recordings of transvesical pressure under isovolumetric conditions (i.e., isovolumetric IVP) and urethral perfusion pressure (UPP). RESULTS: Six weeks after the SCI, the rats showed voiding dysfunction, as indicated by abnormal cystometric measurements (e.g., increased volume threshold, increased contraction amplitude, and increased residual volume, and decreased voided volume). The voiding efficiency (VE) decreased to 13% after the SCI, but increased to 22-34% after applying pudendal afferent stimulation. In addition, pudendal stimulation significantly increased the EUS burst period and increased the difference between the UPP and the high-frequency oscillation (HFO) baselines, and changed the time offset between bladder and EUS activities. These findings suggest that pudendal afferent stimulation improved the VE by prolonging the micturition interval, decreased the urethral resistance, and recovered detrusor-sphincter dyssynergia during the voiding phase. CONCLUSION: This study demonstrates the feasibility of using pudendal neuromodulation in chronic SCI rats. These results could aid in developing an advanced neural prosthesis to restore bladder function in clinical settings.


Assuntos
Terapia por Estimulação Elétrica , Nervo Pudendo/fisiologia , Traumatismos da Medula Espinal/complicações , Uretra/patologia , Transtornos Urinários/terapia , Animais , Modelos Animais de Doenças , Eletromiografia , Feminino , Ratos , Ratos Sprague-Dawley , Micção , Urodinâmica
2.
IEEE Trans Biomed Circuits Syst ; 7(3): 243-55, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23853324

RESUMO

This paper presents the design flow of two high-efficiency class-E amplifiers for the implantable electrical stimulation system. The implantable stimulator is a high-Q class-E driver that delivers a sine-wave pulsed radiofrequency (PRF) stimulation, which was verified to have a superior efficacy in pain relief to a square wave. The proposed duty-cycle-controlled class-E PRF driver designed with a high-Q factor has two operational modes that are able to achieve 100% DC-AC conversion, and involves only one switched series inductor and an unchanged parallel capacitor. The measured output amplitude under low-voltage (LV) mode using a 22% duty cycle was 0.98 V with 91% efficiency, and under high-voltage (HV) mode using a 47% duty cycle was 2.95 V with 92% efficiency. These modes were inductively controlled by a duty-cycle detector, which can detect the duty-cycle modulated signal generated from the external complementary low-Q class-E power amplifier (PA). The design methodology of the low-Q inductive interface for a non-50% duty cycle is presented. The experimental results exhibits that the 1.5-V PA that consumes DC power of 14.21 mW was able to deliver a 2.9-V sine wave to a 500 Ω load. The optimal 60% drain efficiency of the system from the PA to the load was obtained at a 10-mm coupling distance.


Assuntos
Amplificadores Eletrônicos , Terapia por Estimulação Elétrica/instrumentação , Eletrodos Implantados , Animais , Capacitância Elétrica , Fontes de Energia Elétrica , Desenho de Equipamento , Hiperalgesia , Bainha de Mielina/patologia , Neurônios/patologia , Manejo da Dor , Medição da Dor , Ondas de Rádio , Ratos , Processamento de Sinais Assistido por Computador , Temperatura , Tecnologia sem Fio
3.
Artigo em Inglês | MEDLINE | ID: mdl-23118792

RESUMO

The purpose of this study was to evaluate the effect of laser acupuncture (LA) and soft cupping on low back pain. In this study, the subjects were randomly assigned to two groups: active group (real LA and soft cupping) and placebo group (sham laser and soft cupping). Visual analog scale (VAS) and Ryodoraku were used to evaluate the effect of treatment on low back pain in this trial. Laser, 40 mW, wavelength 808 nm, pulse rate 20 Hz, was used to irradiate Weizhong (BL40) and Ashi acupoints for 10 minutes. And the Ryodoraku values were measured 2 times, that is, before and 15 minutes after treatment. The results show that there were significant difference between the first day baseline and the fifth day treatment in VAS in the two groups. Therefore, LA combined with soft cupping or only soft cupping was effective on low back pain. However, the Ryodoraku values of Bladder Meridian of the placebo group have been decreased apparently, and didn't come back to their original values. It means that "cupping" plays the role of "leak or purge" in traditional Chinese medicine (TCM). On the other hand, the Ryodoraku values of Bladder Meridian of the active group have been turned back to almost their original values; "mend or reinforcing" effect is attributed to the laser radiation.

4.
PLoS One ; 7(1): e30294, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22272328

RESUMO

BACKGROUND: Traumatic brain injury (TBI) initiates a neuroinflammatory cascade that contributes to neuronal damage and behavioral impairment. This study was undertaken to investigate the effects of wogonin, a flavonoid with potent anti-inflammatory properties, on functional and histological outcomes, brain edema, and toll-like receptor 4 (TLR4)- and nuclear factor kappa B (NF-κB)-related signaling pathways in mice following TBI. METHODOLOGY/PRINCIPAL FINDINGS: Mice subjected to controlled cortical impact injury were injected with wogonin (20, 40, or 50 mg·kg(-1)) or vehicle 10 min after injury. Behavioral studies, histology analysis, and measurement of blood-brain barrier (BBB) permeability and brain water content were carried out to assess the effects of wogonin. Levels of TLR4/NF-κB-related inflammatory mediators were also examined. Treatment with 40 mg·kg(-1) wogonin significantly improved functional recovery and reduced contusion volumes up to post-injury day 28. Wogonin also significantly reduced neuronal death, BBB permeability, and brain edema beginning at day 1. These changes were associated with a marked reduction in leukocyte infiltration, microglial activation, TLR4 expression, NF-κB translocation to nucleus and its DNA binding activity, matrix metalloproteinase-9 activity, and expression of inflammatory mediators, including interleukin-1ß, interleukin-6, macrophage inflammatory protein-2, and cyclooxygenase-2. CONCLUSIONS/SIGNIFICANCE: Our results show that post-injury wogonin treatment improved long-term functional and histological outcomes, reduced brain edema, and attenuated the TLR4/NF-κB-mediated inflammatory response in mouse TBI. The neuroprotective effects of wogonin may be related to modulation of the TLR4/NF-κB signaling pathway.


Assuntos
Lesões Encefálicas/tratamento farmacológico , Flavanonas/farmacologia , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismo , Animais , Apoptose/efeitos dos fármacos , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/fisiopatologia , Western Blotting , Edema Encefálico/prevenção & controle , Lesões Encefálicas/metabolismo , Lesões Encefálicas/fisiopatologia , Quimiocina CXCL2/genética , Quimiocina CXCL2/metabolismo , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Ensaio de Imunoadsorção Enzimática , Expressão Gênica/efeitos dos fármacos , Marcação In Situ das Extremidades Cortadas , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Permeabilidade/efeitos dos fármacos , Fitoterapia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
5.
Acupunct Electrother Res ; 35(3-4): 133-46, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21319602

RESUMO

Many treatment options for chronic low back pain are available, including varied forms of electric stimulation. But little is known about the electricity effect between electro-acupuncture and pulsed radiofrequency. The objective of this study is to assess the difference in effectiveness of pain relief between pulsed radiofrequency and electro-acupuncture. Visual analog score (VAS) pain score, the Oswestry disability index (ODI) to measure a patient's permanent functional disability, and Short form 36 (SF-36) which is a survey used in health assessment to determine the cost-effectiveness of a health treatment, were used as rating systems to measure the pain relief and functional improvement effect of pulsed radiofrequency and electro-acupuncture, based on the methodological quality of the randomized controlled trials, the relevance between the study groups, and the consistency of the outcome evaluation. First, the baseline status before therapy shows no age and gender influence in the SF-36 and VAS score but it is significant in the ODI questionnaire. From ANOVA analyses, it is apparent that radiofrequency therapy is a significant improvement over electro-acupuncture therapy after one month. But electro-acupuncture also showed functional improvement in the lumbar spine from the ODI. This study provides sufficient evidence of the superiority of pulsed radiofrequency (PRF) therapy for low back pain relief compared with both electro-acupuncture (EA) therapy and the control group. But the functional improvement of the lumbar spine was proved under EA therapy only. Both therapies are related to electricity effects.


Assuntos
Terapia por Estimulação Elétrica , Eletroacupuntura , Dor Lombar/terapia , Doença Crônica/terapia , Feminino , Humanos , Masculino , Medição da Dor , Ondas de Rádio , Resultado do Tratamento
6.
Am J Chin Med ; 32(1): 117-29, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15154291

RESUMO

The purpose of this study was to investigate the effect of the De-Qi sensations of acupuncture (sourness-distension and distension-numbness) stimulation. Fifty-two healthy medical student volunteers were given acupuncture at the Hoku (LI-4) acupoint as they were resting. During a test that lasted 30 minutes, their skin blood flow was measured at the Quchi (LI-11) acupoint and their palm temperature was measured. Our results indicated that acupuncture increased blood flow when the De-Qi sensation occurred. If the needle was twirled a few minutes thereafter and the De-Qi feeling again occurred, the same blood flow increase was seen again. If the needle was not twirled, but the test person felt soreness, numbness and heat sensation within a few minutes after needle insertion, the same blood flow increase was also seen. After acupuncture, Quchi did not show continuous increase of blood flow as did Hoku. Hoku acupuncture also increased palm temperature suggesting that the blood flow increased from cutaneous vessel vasodilation. In conclusion, when the test person felt the sore and numb De-Qi sensation, there was an increase of blood flow at the acupuncture points. Thus, our results suggest that increased flow may be one of the mechanisms accounting for meridian system responses during acupuncture.


Assuntos
Terapia por Acupuntura/métodos , Pele/irrigação sanguínea , Pontos de Acupuntura , Adolescente , Adulto , Feminino , Humanos , Fluxometria por Laser-Doppler , Masculino , Microcirculação/fisiologia , Valores de Referência , Fluxo Sanguíneo Regional
7.
Circ Res ; 92(10): 1145-52, 2003 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-12714561

RESUMO

Whether hypercholesterolemia (HC) can induce proarrhythmic neural and electrophysiological remodeling is unclear. We fed rabbits with either high cholesterol (HC, n=10) or standard (S, n=10) chows for 12 weeks (protocol 1), and with HC (n=12) or S (n=10) chows for 8 weeks (protocol 2). In protocol 3, 10 rabbits were fed with various protocols to observe the effects of different serum cholesterol levels. Results showed that the serum cholesterol levels were 2097+/-288 mg/dL in HC group and 59+/-9 mg/dL in S group for protocol 1 and were 1889+/-577 mg/dL in HC group and 50+/-21 mg/dL in S group for protocol 2. Density of growth-associated protein 43- (GAP43) and tyrosine hydroxylase- (TH) positive nerves in the heart was significantly higher in HC than S in protocol 1. Compared with S, HC rabbits had longer QTc intervals, more QTc dispersion, longer action potential duration, increased heterogeneity of repolarization and higher peak calcium current (ICa) density (14.0+/-3.1 versus 9.1+/-3.4 pA/pF; P<0.01) in protocol 1 and 2. Ventricular fibrillation was either induced or occurred spontaneously in 9/12 of hearts of HC group and 2/10 of hearts in S group in protocol 2. Protocol 3 showed a strong correlation between serum cholesterol level and nerve density for GAP43 (R2=0.94; P<0.001) and TH (R2=0.91; P<0.001). We conclude that HC resulted in nerve sprouting, sympathetic hyperinnervation, and increased ICa. The neural and electrophysiological remodeling was associated with prolonged action potential duration, longer QTc intervals, increased repolarization dispersion, and increased ventricular vulnerability to fibrillation.


Assuntos
Coração/inervação , Hipercolesterolemia/fisiopatologia , Sistema Nervoso Simpático/fisiopatologia , Fibrilação Ventricular/fisiopatologia , Remodelação Ventricular , Potenciais de Ação , Animais , Colesterol/sangue , Colesterol na Dieta , Vasos Coronários/patologia , Modelos Animais de Doenças , Suscetibilidade a Doenças/fisiopatologia , Eletrocardiografia , Técnicas Eletrofisiológicas Cardíacas , Proteína GAP-43/biossíntese , Coração/fisiopatologia , Sistema de Condução Cardíaco/fisiopatologia , Hipercolesterolemia/complicações , Hipercolesterolemia/patologia , Coelhos , Sistema Nervoso Simpático/metabolismo , Sistema Nervoso Simpático/patologia , Triglicerídeos/sangue , Tirosina 3-Mono-Oxigenase/biossíntese , Fibrilação Ventricular/etiologia
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