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Developing efficient nonprecious bifunctional electrocatalysts for hydrogen and oxygen evolution reactions (HER and OER) in the same electrolyte with a low overpotential and large current density presents an appealing yet challenging goal for large-scale water electrolysis. Herein, a unique 3D self-branched hierarchical nanostructure composed of ultra-small cobalt phosphide (CoP) nanoparticles embedded into N, P-codoped carbon nanotubes knitted hollow nanowall arrays (CoPÊNPCNTs HNWAs) on carbon textiles (CTs) through a carbonization-phosphatization process is presented. Benefiting from the uniform protrusion distributions of CoP nanoparticles, the optimum CoPÊNPCNTs HNWAs composites with high abundant porosity exhibit superior electrocatalytic activity and excellent stability for OER in alkaline conditions, as well as for HER in both acidic and alkaline electrolytes, even under large current densities. Furthermore, the assembled CoPÊNPCNTs/CTs||CoPÊNPCNTs/CTs electrolyzer demonstrates exceptional performance, requiring an ultralow cell voltage of 1.50 V to deliver the current density of 10 mA cm-2 for overall water splitting (OWS) with favorable stability, even achieving a large current density of 200 mA cm-2 at a low cell voltage of 1.78 V. Density functional theory (DFT) calculation further reveals that all the C atoms between N and P atoms in CoPÊNPCNTs/CTs act as the most efficient active sites, significantly enhancing the electrocatalytic properties. This strategy, utilizing 2D MOF arrays as a structural and compositional material to create multifunctional composites/hybrids, opens new avenues for the exploration of highly efficient and robust non-noble-metal catalysts for energy-conversion reactions.
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OBJECTIVE: To explore the relationship between the needling sensation of catgut embedding therapy and the depth of embedded catgut so as to improve the safety of the needle insertion and catgut implantation of the therapy. METHODS: Twenty healthy adults were selected. Under the ultrasound, the structure of the cervical Jiaji (EX-B 2) was observed. In the ultrasound guidance, the catgut was embedded. The two-dimensional imaging method was adopted to observe the anatomic structure and the procedure of needle insertion at the cervical Jiaji (EX-B 2). The high-frequency ultrasound was used to collect the images at Jiaji (EX-B 2) of C5 and determine the depths from the skin surface to the different layers of the point. Additionally, the visual analogue scale (VAS) was adopted to score the needling sensations when the needle inserted at different layers. The persistent sensation duration in the local area was followed continuously. RESULTS: Under the ultrasound, the anatomic structure and tissue layers of cervical Jiaji (EX-B 2) were displayed clearly. The difference was significant in the average depth from the skin surface to the subcutaneous tissue, trapezius, splenius capitis, semispinalis capitis, semipinalis cervicis, multifidus and vertebral arch between the males and females (all P<0. 01). During the needle insertion, the sensations were apparently different when the implantation went to different layers. The qi arrival presented when the catgut was embedded to the trapezius, splenius capitis, semispinalis capitis, semipinalis cervicis and multifidus. But the distending pain was the most significant when in the myofascial. Commonly, the embedded catgut 2. 5 cm in length may be implanted deeply to the multifidus and the local needling sensation lasted averagely for (72. 0 ± 10. 2) h. Conclusion Under the ultrasound guidance, the depth of embedded catgut is clearly displayed at cervical Jiaji (EX-B 2). The needle insertion and the implanted material are visible, and the relationship between qi arrival and the layer of needle insertion is determined. The accuracy and safety of minimally invasive catgut embedding therapy is improved in the treatment of cervical spondylosis.
Assuntos
Pontos de Acupuntura , Terapia por Acupuntura , Músculos do Pescoço/diagnóstico por imagem , Qi , Espondilose/terapia , Adulto , Idoso , Categute/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculos do Pescoço/anatomia & histologia , Sensação , Espondilose/diagnóstico por imagem , UltrassonografiaRESUMO
OBJECTIVE: To explore the relationship between the therapeutic effect of minimally invasive embedding therapy and the implanted depth for cervical spondylosis. METHODS: Ninety patients of cervical spondylosis of nerve root type were randomized into a shallow-layer embedding group (subcutaneous layer), a middle-layer embedding group (semispinalis capitis muscle layer) and a deep-layer embedding group (multifidus muscle layer), 30 cases in each one. Jiaji (EX-B 2) of C5 and C6 on the affected side and Dazhui (GV 14) were selected. Under the guide of ultrasound, the catgut was implanted to the corresponding tissue layers. The treatment was given once a week, continuously for 3 weeks in the three groups. The symptoms and physical signs were observed before and after treatment. The pain rating index (PRI), visual analogue scale (VAS) and present pain index (PPI) were assessed. The neck disability index (NDI) was compared. RESULTS: The score of symptoms and function after treatment was increased apparently in the deep-layer embedding group (P < 0.05), which was increased more apparently as compared with those in the shallow-layer embedding group and the middle-layer embedding group (both P < 0.05). PRI, VAS and PPI after treatment were all reduced apparently as compared with those before treatment in the deep-layer embedding group and the middle-layer embedding group (all P < 0.05), which were reduced more remarkably than the shallow-layer embedding group (all P < 0.05). After treatment, the scores of NDI in the deep-layer embedding group and the middle-layer embedding group, were reduced apparently as compared with those before treatment (both P < 0.05), and that in the deep-layer embedding group was reduced more remarkably as compared with the shallow-layer embedding group and the middle-layer embedding group after treatment (both P < 0.05). CONCLUSION: In the acupoint embedding treatment of cervical spondylosis of nerve root type, the efficacy is different apparently in terms of the implantation depth. The deep-layer implantation, meaning to the multifidus muscle layer is more conductive to the treatment of cervical spondylosis.
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Pontos de Acupuntura , Terapia por Acupuntura , Espondilose/terapia , Adulto , Idoso , Categute , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Espondilose/diagnóstico por imagem , Resultado do Tratamento , UltrassonografiaRESUMO
Electroacupuncture (EA) has been used to suppress heroin craving in addicts and the conditioned place preference (CPP) for morphine in the rat. The question remained whether EA by itself will produce some rewarding effect. This was investigated using the CPP procedure in the present study. The results indicated that rats showed a significant preference to the 2 Hz EA-paired compartment. This rewarding effect of EA was prevented by pre-treatment with the opioid receptor antagonist naloxone [2 mg kg(-1), intraperitoneally (i.p.)], CB1 cannabinoid antagonist AM251 (3 µg per rat, intracerebroventricularly) or D1 dopamine receptor antagonist SCH23390 (0.1 mg kg(-1), i.p.), respectively. TempspacetempspaceIt is concluded that 2 Hz EA is capable of inducing CPP in the rat via the activation of the endogenous opioid-, cannabinoid- and dopamine-systems.
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Chronic morphine administration decreases the size of dopamine (DA) neurons in the ventral tegmental area (VTA). These transient morphological changes are accompanied by a reduced sensitivity of morphine-induced conditioned place preference (CPP) after chronic exposure to the drug. In this study we examined alterations in the firing rate of DAergic neurons by means of extracellular recording following chronic morphine exposure and applied 100 Hz electroacupuncture (EA) treatment to reverse the reduced firing rate of these neurons. In the first set of experiments we show that in rats, which received chronic morphine treatment for 14 days, a small dose of morphine was not able to induce a CPP response anymore. However, the sensitivity to morphine was reinstated by consecutive EA treatment for 10 days. The electrophysiological response of VTA DA neurons to morphine was markedly reduced in chronic morphine-treated rats compared to saline-treated controls. A substantial recovery of the reactivity of VTA DA neurons to morphine was observed in rats that received 100 Hz EA for 10 days. Our findings suggest that 100 Hz EA is a potential therapy for the treatment of opiate addiction by normalizing the activity of VTA DA neurons.
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Analgésicos Opioides/farmacologia , Dopamina/metabolismo , Eletroacupuntura/métodos , Morfina/farmacologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Área Tegmentar Ventral/efeitos dos fármacos , Área Tegmentar Ventral/metabolismo , Analgésicos Opioides/administração & dosagem , Animais , Comportamento de Escolha , Esquema de Medicação , Masculino , Morfina/administração & dosagem , Ratos , Ratos Sprague-Dawley , Substância Negra/efeitos dos fármacos , Substância Negra/metabolismoRESUMO
The aim of this study was to observe the effect of electroacupuncture (EA) on chronic morphine-induced neuronal morphological changes in the ventral tegmental area (VTA) in rats at electron-microscopic level. Fourteen days of administering escalating doses of morphine induced pathological morphological changes of neurons in the VTA: the rough endoplasmic reticulum swelled, membrane configuration of the nucleus and mitochondria blurred, and structure of myelin sheath changed. Both 2 and 100 Hz EA treatment reversed the morphological alterations induced by chronic morphine administration. The findings provide new evidence that EA may serve as a potential therapy in treating opiate addiction.
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Eletroacupuntura , Dependência de Morfina/patologia , Morfina/toxicidade , Área Tegmentar Ventral/efeitos dos fármacos , Animais , Tamanho Celular , Retículo Endoplasmático Rugoso/efeitos dos fármacos , Retículo Endoplasmático Rugoso/patologia , Masculino , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Bainha de Mielina/efeitos dos fármacos , Bainha de Mielina/patologia , Neurônios/efeitos dos fármacos , Neurônios/patologia , Membrana Nuclear/efeitos dos fármacos , Membrana Nuclear/patologia , Ratos , Ratos Sprague-Dawley , Área Tegmentar Ventral/patologiaRESUMO
Chronic morphine administration induces functional and morphological alterations in the mesolimbic dopamine system (MLDS), which is believed to be the neurobiological substrate of opiate addiction. Our previous studies have demonstrated that peripheral electrical stimulation (PES) can suppress morphine withdrawal syndrome and morphine-induced conditioned place preference (CPP) in rats. The present study was designed to investigate if PES could reverse the cell size reduction induced by chronic morphine treatment in the ventral tegmental area (VTA), which is an important area of the MLDS. Immunohistochemical observations showed that the cell size of dopaminergic neurons in the VTA reduced significantly in the chronic morphine-treated rats with a concomitant decrease in the number of BDNF-positive cells compared to the saline-treated rats. A much milder morphological change, accompanying with an increased number of BDNF-positive cells, was observed in dopaminergic neurons in the rats that received repeated 100 Hz PES after morphine withdrawal. In another experiment, enzyme-linked immunosorbent assay (ELISA) reconfirmed a significant up-regulation of BDNF protein level in the VTA in the rats received 100 Hz PES after morphine abstinence. These results indicate that PES could facilitate the morphological recovery of the VTA dopaminergic cells damaged by chronic morphine treatment and up-regulate the BDNF protein level in the VTA. Activation of endogenous BDNF by PES may play a role in the recovery of the injured dopaminergic neurons in the morphine addictive rats.
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Fator Neurotrófico Derivado do Encéfalo/metabolismo , Tamanho Celular/efeitos dos fármacos , Morfina/administração & dosagem , Entorpecentes/administração & dosagem , Neurônios/efeitos dos fármacos , Área Tegmentar Ventral/citologia , Análise de Variância , Animais , Comportamento Animal/efeitos dos fármacos , Tamanho Celular/efeitos da radiação , Modelos Animais de Doenças , Estimulação Elétrica/métodos , Ensaio de Imunoadsorção Enzimática , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Regulação da Expressão Gênica/efeitos da radiação , Masculino , Fator de Crescimento Neural/metabolismo , Vias Neurais/fisiologia , Vias Neurais/efeitos da radiação , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Tirosina 3-Mono-Oxigenase/metabolismo , Área Tegmentar Ventral/efeitos dos fármacosRESUMO
Glutamate receptors are known to be densely distributed in the forebrain rewarding circuits, and glutamatergic transmission is actively involved in the regulation of rewarding and reinstating effects of drugs of abuse. Here we investigated the possible involvement of the N-methyl-D-aspartate (NMDA) receptors in the reinstatement of extinguished morphine conditioned place preference (CPP) in rats. We found that previously extinguished morphine (3 mg/kg, i.p.) CPP was markedly reinstated by a priming injection of morphine (2 mg/kg, i.p.) or an acute environmental stressor (forced swim for 10 min), but not by the stress induced by a 24-h food deprivation. Parallel with this, protein levels of the NMDA receptor 2B subunit (NR2B) were elevated in the nucleus accumbens (NAc) and the hippocampus, but not the prefrontal cortex, of reinstated rats. Systemic administration of an NR2B selective antagonist ifenprodil (1, 3, 10 mg/kg, i.p.) attenuated the reinstatement induced by a priming morphine injection, although not by the forced swim. Ifenprodil (2.0 microg/rat) directly injected into the NAc shell or the CA1 region of the dorsal hippocampus produced a similar effect. These results indicate that the NR2B-containing NMDA receptors in the NAc and the dorsal hippocampus play a significant role in mediating the reinstatement of rewarding responses to morphine.