RESUMO
One challenge of the citrus industry is the treatment and disposal of its effluents due to their high toxicity, substantial organic load, and consequent resistance to conventional biotechnological processes. This study introduces a novel approach, using electrochemical oxidation with a boron-doped diamond anode to efficiently remove organic compounds from biodegraded pulp wash (treated using the fungus Pleurotus sajor-caju.) The findings reveal that employing a current density of 20 mA cm-2 achieves notable results, including a 44.1% reduction in color, a 70.0% decrease in chemical oxygen demand, an 88.0% reduction in turbidity, and an impressive 99.7% removal of total organic carbon (TOC) after 6 h of electrolysis. The energy consumption was estimated at 2.93 kWh g-1 of removed TOC. This sequential biological-electrochemical procedure not only significantly reduced the mortality rate (85%) of Danio rerio embryos but also reduced the incidence of morphologically altered parameters. Regarding acute toxicity (LC50) of the residue, the process demonstrated a mortality reduction of 6.97% for D. rerio and a 40.88% lethality decrease for Lactuca sativa seeds. The substantial reduction in toxicity and organic load observed in this study highlights the potential applicability of combined biological and electrochemical treatments for real agroindustrial residues or their effluents.
Assuntos
Diamante , Poluentes Químicos da Água , Diamante/química , Poluentes Químicos da Água/análise , Eletrólise/métodos , Compostos Orgânicos , Eletrodos , OxirreduçãoRESUMO
Iron-carbon micro-electrolysis is effective for the removal of phosphorus in wastewater; however, meeting the stringent emission standards required for treatment is difficult. To meet these treatment standards, modified micro-electrolytic fillers were prepared from iron dust, powdered activated carbon, clay, and additives using an elevated temperature roasting process under an inert atmosphere. The results show that among several additives, the modified micro-electrolytic (Fe/C-MgCO3) fillers using MgCO3 were the most effective at phosphorus removal. The preparation conditions for the Fe/C-MgCO3 fillers and their effects on phosphorus removal performance were investigated. Under the optimal preparation conditions (calcination temperature: 800 °C, Fe/C = 4:1, clay content 20%, and 5% MgCO3), the filler yielded a high compressive strength of 3.5 MPa, 1 h water absorption rate of 25.7%, and specific surface area and apparent density of 154.2 m2/g and 2689.2 kg/m3, respectively. The iron-carbon micro-electrolysis process removed 97% of phosphorus in the wastewater by using the Fe/C-MgCO3 fillers, which was 14% more than the Fe/C filler. Electrostatic adsorption and surface precipitation were identified as the main phosphorus removal mechanisms, and the surface of the Fe/C-MgCO3 filler was continuously updated. These results demonstrated that Fe/C-MgCO3 is a promising filler for phosphorus removal in water treatment.
Assuntos
Fósforo , Águas Residuárias , Argila , Eletrólise/métodos , Ferro , Eliminação de Resíduos Líquidos/métodosRESUMO
Microplastics have been identified as a kind of emerging pollutant with potential ecological risks, and it is an urgent endeavor to find proper technologies for their remediation. Electrochemical advanced oxidation process (EAOP) technology has exhibited robust performance in the removal of various refractory organic pollutants. In this study, we explored a new remediation strategy for polystyrene microplastics (PS MPs), introducing sodium dodecyl sulfate (SDS) to enhance its degradation performance in boron-doped diamond (BDD) anode adopted EAOP. At first, we investigated the degradation behaviors of SDS in the BDD electrolysis. According to the SDS half-life under various current densities, the SDS addition strategy into EAOP is proposed; that is, supplement SDS to 500â¯mg/L at every half-life during electrolysis except the last cycle. Results indicated that SDS addition greatly enhanced MPs degradation rate in 72â¯h of EAOP, about 1.35-2.29 times higher than that in BDD electrolysis alone. The SDS assisted EAOP also led to more obvious changes in the particle size, morphology, and functional groups of the MPs. After treatment, a variety of alkyl-cleavage and oxidation products were identified, which attributed to the strong attack of oxidants (i.e., persulfate) on the MPs. The enhanced persulfate generation and oxidants adsorption on MPs can explain the enhancement effect in the EAOP strategy. Cost analysis results showed the surfactant only accounts for < 0.05% of the total operating costs in the SDS assisted EAOP. In general, the current study provided new insight into the effective way to improve the EAOP efficiency of microplastics.
Assuntos
Microplásticos , Poluentes Químicos da Água , Dodecilsulfato de Sódio , Tensoativos , Poliestirenos , Plásticos , Diamante , Eletrólise/métodos , Boro , Oxirredução , Eletrodos , OxidantesRESUMO
This study investigated the potential of a novel fabricated black phosphorus (BP) nanoparticle electrode as an alternative to noble metal-based catalysts for application in electrolysis. The BP electrode was compared with other conventional catalysts (boron-doped diamond (BDD) and a dimensional stable electrode (DSA)) under different electrolyte conditions for the generation of specific oxidants (e.g., OHâ¢, HOCl, OCl-, SO4⢠-) in the bulk phase during electrolysis. In the presence of sulfate-based electrolyte, results on the electrochemical oxidation showed that the BP not only resulted in an 8-fold increase in the current efficiency compared to DSA, but also reduced energy consumptions by approximately 30-fold. Moreover, electrolysis using certain electrodes (i.e., BDD) under high current densities in the presence of chlorine-based electrolyte has been reported to be hazardous to the water system due to the generation of toxic chlorine oxyanions (i.e., perchlorate), which necessitates the operation of a post-treatment process. Likewise, application of the BDD electrode was confirmed to produce perchlorate under high current densities, while no by-product was generated by electrolysis with the BP electrode. Finally, multiple degradation pathways for selective water treatment was monitored under oxidation with the BP electrode. To the best of our knowledge, this study is the first to apply the novel fabricated BP electrode as the anodic catalyst for the treatment of a water system.
Assuntos
Boro , Poluentes Químicos da Água , Cloro , Diamante , Eletrodos , Eletrólise/métodos , Oxidantes , Oxirredução , Percloratos , Fósforo , SulfatosRESUMO
OBJECTIVES: To determine the additional effect of dry needling (DN) or percutaneous needle electrolysis (PNE) combined with eccentric exercise (EE) and determine which is the most effective for patients with patellar tendinopathy (PT). DESIGN: Blinded, randomized controlled trial, with follow-up at 10 and 22 weeks. SETTINGS: Recruitment was performed in sport clubs. Diagnosis and intervention were conducted at San Jorge University. PARTICIPANTS: Patients (N=48) with PT with pain for at least 3 months between the ages of 18 and 45 years. INTERVENTIONS: Three interventions were carried out: DN and EE, PNE and EE, and EE with sham needle as the control group. MAIN OUTCOME MEASURES: Disability was measured using the Victorian Institute of Sports Assessment Questionnaire, patellar tendon. Visual analog scale was used to measure pain over time, the Short Form-36 was used to measure quality of life, and ultrasound was used to measure structural abnormalities. RESULTS: A total of 48 participants (42 men, 6 women; average age, 32.46y; SD, 7.14y) were enrolled. The improvement in disability and pain in each group between baseline and post-treatment and baseline and follow-up was significant (P≤.05), without differences among groups. CONCLUSION: DN or PNE combined with an EE program has not shown to be more effective than a program of only EE to improve disability and pain in patients with PT in the short (10wk) and medium (22wk) terms. Clinical improvements were not associated with structural changes in the tendon.
Assuntos
Agulhamento Seco/métodos , Eletrólise/métodos , Terapia por Exercício/métodos , Ligamento Patelar/fisiopatologia , Tendinopatia/terapia , Adulto , Terapia Combinada , Avaliação da Deficiência , Feminino , Humanos , Masculino , Medição da Dor , Qualidade de Vida , Método Simples-CegoRESUMO
In the transportation of petroleum, large amount of oil polluted water will be produced, and the oil polluted water pumping into ocean will destroy ocean environment. To address oil-bearing ballast water, we fabricated a novel type of Fe-C microelectrolysis filler by using magnet powder, coconut shell biochar powder, bentonite, ammonium oxalate, and nickel powder. The COD and oil content removal efficiencies of 100 g/L oily wastewater were approximately 79.82% and 91.68%, respectively, after 100 min treatment at the following conditions: Fe-C mass ratio, 5:1; bentonite content, 20%; calcination temperature, 900 °C; calcination time, 2 h; ammonium oxalate content, 1.5%; and amount of nickel addition, 6.78%. The characteristics of the Fe-C microelectrolysis filler were analyzed. The surface structure of the filler was loose and porous, and its pores were developed. The Brunauer-Emmett-Teller (BET) surface area reached 49.4667 m2 g-1. A microelectrolysis filler is mainly mesoporous and contains large pores. Its average pore size is 2.6942 nm. Meanwhile, the results of our XRD analysis showed that some fillers were metal oxides, and most of them were simple metal substances.
Assuntos
Eletrólise/métodos , Águas Residuárias/química , Poluentes Químicos da Água/química , Bentonita/química , Eletrólise/instrumentação , Níquel/química , Petróleo/análise , Temperatura , Purificação da Água/métodosRESUMO
BACKGROUND: Both manual therapy techniques and dry needling have shown to be effective treatment options for the treatment of plantar heel pain; however, in recent years, other techniques based on dry needling (DN), such as percutaneous needle electrolysis (PNE), have also emerged. Currently, PNE is being used in clinical practice to manage myofascial trigger points, despite the lack of studies comparing the effects of this technique over dry needling. Therefore, the aim of this randomized controlled study is to compare the effectiveness of DN versus PNE for improving the level of pain experienced by patients suffering from plantar heel pain provoked by myofascial trigger points. METHODS: A randomized controlled trial will be conducted with blinded participants and outcome assessors. A sample of 94 patients with a medical diagnosis of plantar heel pain will be recruited and divided into two treatment groups. Eligible participants will be randomly allocated to either (a) treatment group with DN and a self-stretching home program or (b) treatment group with PNE and a self-stretching home program. Each group will receive one treatment session per week over a period of 4 weeks. The primary outcome measure will be the pain subscale of the Foot Health Status Questionnaire. The secondary outcome measures will be a visual analogue scale for pain (average and highest level of pain experienced during the previous 48 h; level of pain immediately after the treatment session) and health-related quality of life (assessed using the EuroQoL-5 dimensions). Cost-effectiveness data will be extracted based on the EuroQoL-5 dimensions. Follow-up measurements will take place at baseline and at 4, 8, 12, 26, and 52 weeks. DISCUSSION: The justification for this trial is the need to improve current understanding regarding the effectiveness of treatments targeting the rehabilitation of plantar heel pain. This study will be the first randomized controlled trial to directly compare the effectiveness of DN and PNE combined with a specific stretching program for the treatment of plantar heel pain provoked by myofascial trigger points. TRIAL REGISTRATION: Clinical Trials NCT03236779. Registered at clinicaltrials.gov 2 August 2017.
Assuntos
Terapia por Acupuntura/métodos , Eletrólise/métodos , Fasciíte Plantar/terapia , Agulhas , Manejo da Dor/métodos , Medição da Dor/métodos , Terapia por Acupuntura/instrumentação , Adulto , Método Duplo-Cego , Eletrólise/instrumentação , Fasciíte Plantar/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Manejo da Dor/instrumentação , Estudos Prospectivos , Resultado do Tratamento , Adulto JovemRESUMO
In the present study, the dual effects of slightly acidic electrolyzed water (SAEW) treatment on γ-aminobutyric acid (GABA) and rutin accumulation of germinated buckwheat were evaluated during germination. The results showed that SAEW treatment (pH 5.83, ACC of 20.3 mg/L) could promote the accumulation of GABA and rutin in germinated buckwheat. The GABA and rutin contents of SAEW-germinated buckwheat reached 143.20 and 739.9 mg/100 g respectively, which is significantly higher than those of control (P<0.05). Moreover, SAEW treatment could increase the activity of glutamic acid decarboxylase (GAD) and phenylalanine ammonialyase (PAL) and thus result in the GABA and rutin accumulation of germinated buckwheat. The results suggested that SAEW treatment could promote the rutin accumulation of germinated buckwheat by influencing phenylpropanoid secondary metabolic pathway instead of the inhibition of rutin degrading enzyme (RDE) activity. In addition, SAEW treatment had no adverse impact on the sprouts growth and could reduce the microbial populations of germinated buckwheat during germination.
Assuntos
Eletrólise/métodos , Fagopyrum/química , Germinação/efeitos dos fármacos , Glutamato Descarboxilase/química , Rutina/química , Água/química , Rutina/farmacologia , Ácido gama-AminobutíricoRESUMO
BACKGROUND: Ultrasound (US)-guided percutaneous needle electrolysis (PNE) is a novel minimally invasive approach, which involves the application of a galvanic current via an acupuncture needle. As in any procedure involving needling, vagal reactions have been reported during PNE. OBJECTIVE: To examine for changes in autonomic activity during the US-guided PNE technique on healthy patellar tendons by measurement and analysis of heart rate variability (HRV). METHODS: Twenty-two male footballers were randomly allocated to: a control group (11 players), for whom HRV was recorded for 10â min, both at rest and during an exhaustive US examination of the patellar tendon and adjacent structures; and an experimental group (11 players), for whom HRV was recorded for 10â min, both at rest and during application of US-guided PNE on the patellar tendon. The following HRV parameters were assessed: mean NN interval, mean heart rate, time domain parameters (SDNN, rMSSD, pNN50), diameters of the Poincaré plot (SD1, SD2), stress score, and sympathetic/parasympathetic ratio. RESULTS: There were no differences between groups in any baseline measurements, nor were there any significant differences between control group measurements (baseline vs intervention). The experimental group exhibited statistically significant increases in SDNN/SD1 (p=0.02/p=0.03) and SD2 (p=0.03), indicating increased parasympathetic and decreased sympathetic activity, respectively. CONCLUSIONS: US-guided PNE was associated with an autonomic imbalance characterised by greater parasympathetic activity, which could potentially result in a vasovagal reaction. Care should be taken to monitor for adverse reactions during US-guided PNE and simple HRV indicators may have a role in early detection.
Assuntos
Eletrólise , Ligamento Patelar , Sistema Nervoso Autônomo/fisiologia , Eletrólise/métodos , Eletrólise/psicologia , Frequência Cardíaca , Humanos , Masculino , Ligamento Patelar/inervação , Ultrassonografia de Intervenção/psicologiaRESUMO
An integrated dark fermentation and microbial electrochemical cell (MEC) process was evaluated for hydrogen production from sugar beet juice. Different substrate to inoculum (S/X) ratios were tested for dark fermentation, and the maximum hydrogen yield was 13% of initial COD at the S/X ratio of 2 and 4 for dark fermentation. Hydrogen yield was 12% of initial COD in the MEC using fermentation liquid end products as substrate, and butyrate only accumulated in the MEC. The overall hydrogen production from the integrated biohydrogen process was 25% of initial COD (equivalent to 6 mol H2/mol hexoseadded), and the energy recovery from sugar beet juice was 57% using the combined biohydrogen.
Assuntos
Beta vulgaris/metabolismo , Fermentação/fisiologia , Hidrogênio/metabolismo , Eletrólise/métodosRESUMO
Intensified nutrient removal and odor control in a novel electrolysis-integrated tidal flow constructed wetland were evaluated. The average removal efficiencies of COD and NH4(+)-N were above 85% and 80% in the two experimental wetlands at influent COD concentration of 300 mg/L and ammonium nitrogen concentration of 60 mg/L regardless of electrolysis integration. Effluent nitrate concentration decreased from 2.5mg/L to 0.5mg/L with the reduction in current intensity from 1.5 mA/cm(2) to 0.57 mA/cm(2). This result reveals the important role of current intensity in nitrogen transformation. Owing to the ferrous and ferric iron coagulant formed through the electro-dissolution of the iron anode, electrolysis integration not only exerted a positive effect on phosphorus removal but also effectively inhibited sulfide accumulation for odor control. Although electrolysis operation enhanced nutrient removal and promoted the emission of CH4, no significant difference was observed in the microbial communities and abundance of the two experimental wetlands.
Assuntos
Eletrólise/métodos , Nitrogênio/isolamento & purificação , Odorantes/prevenção & controle , Fósforo/isolamento & purificação , Movimentos da Água , Áreas Alagadas , Bactérias/efeitos dos fármacos , Bactérias/genética , Biodegradação Ambiental/efeitos dos fármacos , Análise da Demanda Biológica de Oxigênio , Dióxido de Carbono/análise , DNA Ribossômico/genética , Desnitrificação/efeitos dos fármacos , Eletricidade , Hidrogênio/farmacologia , Metano/análise , Óxido Nitroso/análise , Compostos Orgânicos/isolamento & purificação , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/isolamento & purificação , Qualidade da ÁguaRESUMO
BACKGROUND: Ultrasound (US)-guided percutaneous needle electrolysis (PNE) is a novel minimally invasive approach which consists of the application of a galvanic current through an acupuncture needle. OBJECTIVE: To evaluate the clinical and ultrasonographic effectiveness of a multimodal programme (PNE, eccentric exercise (EccEx) and stretching) in the short term for patients with chronic lateral epicondylitis, and to determine whether the clinical outcomes achieved decline over time. METHODS: A one-way repeated measures study was performed in a clinical setting in 36 patients presenting with lateral epicondylitis. The patients received one session of US-guided PNE per week over 4-6â weeks, associated with a home programme of EccEx and stretching. The main outcome measures were severity of pain, disability (Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire), structural tendon changes (US), hypervascularity and patients' perceptions of overall outcome. Measurements at 6, 26 and 52â weeks follow-up included recurrence rates (increase in severity of pain or disability compared with discharge), perception of overall outcome and success rates. RESULTS: All outcome measures registered significant improvements between pre-intervention and discharge. Most patients (n=30, 83.3%) rated the overall outcome as 'successful' at 6â weeks. The ultrasonographic findings showed that the hypoechoic regions and hypervascularity of the extensor carpi radialis brevis changed significantly. At 26 and 52â weeks, all participants (n=32) perceived a 'successful' outcome. Recurrence rates were null after discharge and at follow-up at 6, 26 and 52â weeks. CONCLUSIONS: Symptoms and degenerative structural changes of chronic lateral epicondylitis are reduced after US-guided PNE associated with EccEx and stretching, with encouragingly low recurrences in the mid to long term. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov identifier: NCT02085928.
Assuntos
Cotovelo , Eletrólise/métodos , Dor Musculoesquelética , Agulhas , Tendões , Cotovelo de Tenista/terapia , Acupuntura , Adulto , Braço , Feminino , Humanos , Masculino , Exercícios de Alongamento Muscular , Medição da Dor , Inquéritos e Questionários , Fatores de Tempo , Resultado do TratamentoRESUMO
Alkaline electrolysed water (AlEW) with different pHs was produced by an electrolysed water generator through adjusting the electric current and voltage. The produced AlEW had a pH above 10, and a low oxidation-reduction potential (ORP) of less than -560 mV. In the current study, the effectiveness of AlEW on decontamination of aflatoxin B1 (AFB1) in various edible plant oils was investigated. The character of AlEW, oil type and the volume of AlEW were major factors which could influence the AFB1 elimination effectiveness. AlEW with pH 12.2 had the greater potential to remove AFB1. When 10 ml AlEW with pH 12.2 were added to 5 g peanut oil or olive oil (fortified level at 40 µg kg(-1)), followed by oscillation for 5 min at 20 °C, the removal rate of AFB1 could reach nearly 100%. The volume of AlEW needed to completely remove the AFB1 varied with the pH of AlEW and with the oil type. The degradation products of AFB1 were also investigated.
Assuntos
Aflatoxina B1/química , Descontaminação/métodos , Eletrólise/métodos , Óleos de Plantas/química , Contaminação de Alimentos/análiseRESUMO
BACKGROUND: Perceptual and psychic alterations and thought disorder are fundamental elements of schizophrenia symptoms, a pathology associated with an abnormal macro- and microcircuitry of several brain areas including the prefrontal cortex (PFC). Alterations in information processing in PFC may partly underlie schizophrenia symptoms. METHODS: The 5-HT(2A/2C) agonist DOI and antipsychotic drugs were administered to anesthetized rats. Single unit and local field potential (LFP) extracellular recordings were made in medial PFC (mPFC). Electrolytic lesions were performed in the thalamic nuclei. RESULTS: DOI markedly disrupts cellular and network activity in rat PFC. DOI altered pyramidal discharge in mPFC (39% excited, 27% inhibited, 34% unaffected; n = 51). In all instances, DOI concurrently reduced low-frequency oscillations (.3-4 Hz; power spectrum: .25 +/- .02 and .14 +/- .01 microV(2) in basal conditions and after 50-300 microg/kg intravenous (i.v.) DOI, respectively; n = 51). Moreover, DOI disrupted the temporal association between the active phase of LFP and pyramidal discharge. Both effects were reversed by M100907 (5-HT(2A) receptor antagonist) and were not attenuated by thalamic lesions, supporting an intracortical origin of the effects of DOI. The reduction in low-frequency oscillations induced by DOI was significantly reversed by the antipsychotic drugs haloperidol (.1-.2 mg/kg i.v.) and clozapine (1 mg/kg i.v.). CONCLUSIONS: DOI disorganizes network activity in PFC, reducing low-frequency oscillations and desynchronizing pyramidal discharge from active phases of LFP. These effects may underlie DOI's psychotomimetic action. The reversal by clozapine and haloperidol indicates that antipsychotic drugs may reduce psychotic symptoms by normalizing an altered PFC function.
Assuntos
Anfetaminas/farmacologia , Antipsicóticos/farmacologia , Relógios Biológicos/efeitos dos fármacos , Clozapina/farmacologia , Alucinógenos/farmacologia , Córtex Pré-Frontal/efeitos dos fármacos , Potenciais de Ação/efeitos dos fármacos , Análise de Variância , Animais , Relação Dose-Resposta a Droga , Eletroencefalografia , Eletrólise/métodos , Potenciais Evocados/efeitos dos fármacos , Fluorbenzenos/farmacologia , Análise de Fourier , Masculino , Neurônios/efeitos dos fármacos , Piperidinas/farmacologia , Córtex Pré-Frontal/citologia , Ratos , Ratos Wistar , Antagonistas da Serotonina/farmacologia , Tálamo/lesões , Tálamo/fisiologiaRESUMO
Hypothalamic supraoptic nucleus (SON) has been demonstrated to involve in pain modulation. Acupuncture analgesia is a very useful clinical skill for pain relief, which has over 2500-year history in China. The present study investigated the effect of SON on acupuncture analgesia in the rat. Electrical stimulation of the SON or microinjection of a small dose L-glutamate sodium into the SON enhanced acupuncture analgesia in a dose-dependent manner, while cauterization of the SON weakened acupuncture analgesia. Pituitary removal did not influence the effect of L-glutamate sodium that enhanced acupuncture analgesia in the SON. The data suggested that the neurons and not the nerve fibers in the SON played an important role in acupuncture analgesia, which effect might be through the central nervous system rather than the hypothalamo-neurohypophyseal system.
Assuntos
Analgesia por Acupuntura/métodos , Núcleo Supraóptico/fisiologia , Análise de Variância , Animais , Comportamento Animal , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Estimulação Elétrica/efeitos adversos , Estimulação Elétrica/métodos , Eletrólise/métodos , Ácido Glutâmico/administração & dosagem , Masculino , Microinjeções , Medição da Dor , Limiar da Dor/efeitos dos fármacos , Limiar da Dor/fisiologia , Limiar da Dor/efeitos da radiação , Hipófise/cirurgia , Ratos , Ratos Sprague-Dawley , Núcleo Supraóptico/efeitos dos fármacos , Núcleo Supraóptico/lesões , Núcleo Supraóptico/efeitos da radiaçãoRESUMO
Cingulothalamic neurons develop topographic patterns of cue-elicited neuronal activity during discrimination learning. These patterns are context-related and are degraded by hippocampal lesions, suggesting that hippocampal modulation of cingulothalamic activity results in the expression of the patterns, which could promote the retrieval of context-appropriate responses and memories. This hypothesis was tested by training rabbits (Oryctolagus cuniculus) with fornix lesions concurrently on two discrimination tasks (approach and avoidance) in different contexts. Because the same conditioned stimuli were used for both tasks, contextual information was critical for overcoming intertask interference during concurrent task acquisition. The lesions degraded the topographic patterns and significantly impaired concurrent learning, suggesting that hippocampal-cingulothalamic interactions and the resulting topographic patterns are critical for processing contextual information needed to defeat interference.
Assuntos
Aprendizagem da Esquiva/fisiologia , Aprendizagem por Discriminação/fisiologia , Fórnice/fisiologia , Giro do Cíngulo/fisiologia , Neurônios/fisiologia , Tálamo/fisiologia , Potenciais de Ação/fisiologia , Animais , Comportamento Animal , Encefalopatias/fisiopatologia , Condicionamento Psicológico/fisiologia , Eletrólise/métodos , Fórnice/lesões , Masculino , Coelhos , Fatores de TempoRESUMO
Biomimetic apatite coatings on micro-arc oxidized titania films were investigated and their apatite-inducing ability was evaluated in a simulated body fluid (1.0 SBF) as well as in a 1.5 times concentrated SBF (1.5 SBF). Titania-based films on titanium were prepared by micro-arc oxidation at various applied voltages (250-500 V) in an electrolytic solution containing beta-glycerophosphate disodium salt pentahydrate (beta-GP) and calcium acetate monohydrate (CA). Macro-porous, Ca- and P-containing titania-based films were formed on the titanium substrates. The phase, Ca and P content, morphology, and thickness of the films were strongly dependent on the applied voltage. In particular, Ca- and P-containing compounds such as CaTiO3, beta-Ca2P2O7 and alpha-Ca3(PO4)2 were produced at higher voltages (>450 V). When immersed in 1.0 SBF, a carbonated hydroxyapatite was induced on the surfaces of the films oxidized at higher voltages (>450 V) after 28 days, which is closely related to the Ca- and P-containing phases. The use of 1.5 SBF shortened the apatite induction time and apatite formation was confirmed even on the surface of the films oxidized at 350 V, which suggests that the incorporated Ca and P in the titania films play a similar role to the Ca- and P-containing compounds in the SBF.
Assuntos
Apatitas/química , Materiais Biomiméticos/química , Líquidos Corporais/química , Cálcio/química , Materiais Revestidos Biocompatíveis/química , Fósforo/química , Titânio/química , Animais , Eletrólise/métodos , Humanos , Teste de Materiais , Conformação Molecular , Oxirredução , Propriedades de SuperfícieRESUMO
INTRODUCTION: Electrochemical treatment (EChT) has been taken under serious consideration as being one of several techniques for local treatment of malignancies. The advantage of EChT is the minimal invasive approach and the absence of serious side effects. Macroscopic, histopathological and ultra-structural findings in liver following a four-electrode configuration (dog) and a two-electrode EChT design (dog and rat) were studied. MATERIALS AND METHODS: 30 female Sprague-Dawley rats and four female beagle dogs were studied with EChT using Platinum:Iridium electrodes and the delivered dose was 5, 10 or 90 C (As). After EChT, the animals were euthanized. RESULTS: The distribution of the lesions was predictable, irrespective of dose and electrode configuration. Destruction volumes were found to fit into a logarithmic curve (dose-response). Histopathological examination confirmed a spherical (rat) and cylindrical/ellipsoidal (dog) lesion. The type of necrosis differed due to electrode polarity. Ultra-structural analysis showed distinct features of cell damage depending on the distance from the electrode. Histopathological and ultra-structural examination demonstrated that the liver tissue close to the border of the lesion displayed a normal morphology. CONCLUSIONS: The in vivo dose-planning model is reliable, even in species with larger tissue mass such as dogs. A multi-electrode EChT-design could obtain predictable lesions. The cellular toxicity following EChT is clearly identified and varies with the distance from the electrode and polarity. The distinct border between the lesion and normal tissue suggests that EChT in a clinical setting for the treatment of liver tumours can give a reliable destruction margin.
Assuntos
Terapia por Estimulação Elétrica/métodos , Eletrólise/métodos , Neoplasias Hepáticas/terapia , Fígado , Animais , Cães , Eletroquímica , Eletrodos , Feminino , Técnicas Histológicas , Irídio/química , Fígado/patologia , Fígado/ultraestrutura , Microscopia Eletrônica , Modelos Animais , Necrose , Platina/química , RatosRESUMO
Anti-tumour effects of direct current electrotherapy are attributed to different mechanisms depending on the electrode configuration and on the parameters of electric current. The effects mostly arise from the electrochemical products of electrolysis. Direct toxicity of these products to tumour tissue is, however, not a plausible explanation for the observed tumour growth retardation in the case when the electrodes are placed into healthy tissue surrounding the tumour and not into the tumour itself. The hypothesis that the anti-tumour effectiveness of electrotherapy could result from disturbed blood flow in tumours was tested by the measurement of changes in blood perfusion and oxygenation in tumours with three different methods (in vivo tissue staining with Patent Blue Violet dye, polarographic oximetry, near-infrared spectroscopy). The effects induced by electrotherapy were evaluated in two experimental tumour models: Sa-1 fibrosarcoma in A/J mice and LPB fibrosarcoma in C57B1/6 mice. We found that perfusion and oxygenation were significantly decreased after electrotherapy. Good agreement between the results of different methods was observed. The effect of electrotherapy on local perfusion of tumours is probably the prevalent mechanism of anti-tumour action for the particular type of electrotherapy used in the study. The importance of this effect should be considered for the optimization of electrotherapy protocols in experimental and clinical trials. The non-invasive technique of near-infrared spectroscopy proved to be a reliable method for detecting perfusion and oxygenation changes in small solid tumours.
Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Terapia por Estimulação Elétrica/métodos , Fibrossarcoma/irrigação sanguínea , Fibrossarcoma/terapia , Animais , Modelos Animais de Doenças , Terapia por Estimulação Elétrica/efeitos adversos , Eletroquímica/métodos , Eletrólise/métodos , Eritrócitos/patologia , Fibrossarcoma/patologia , Humanos , Camundongos , Camundongos Endogâmicos A , Espectrofotometria Infravermelho/instrumentação , Espectrofotometria Infravermelho/métodosRESUMO
Foi idealizado e construido um aparelho que utiliza a corrente elétrica galvânica em baixa amperagem (100m A ,200m A, 300m A) com o propósito de causar esclerose em vasos venosos de pequeno calibre, utilizando a veia marginal da orelha direita do coelho. O presente estudo buscou verificar em modelo experimental, o efeito da corrente elétrica galvânica em baixa amperagem. Foram utilizados 45 coelhos Nova Zelandia, distribuídos em 3 grupos de 15 animais , sendo utilizada a orelha esquerda como controle e a orelha direita como experimento. No grupo experimento os animais do grupo I foram submetidos à corrente elétrica galvânica de 100m A , no grupo II à 200m A, e no grupo III à 300m . No grupo controle, os animais foram submetidos somente ao procedimento mecânico de aplicaçäo da agulha ao longo da veia marginal da orelha esquerda, sendo realizado uma, duas e três aplicaçöes com intervalo de sete dias entre cada aplicaçäo. Todos os animais foram avaliados quatorze dias após a última aplicaçäo, em aspectos macro e microscópicos. Os resultados mostraram que, tanto a corrente elétrica galvânica em baixa amperagem, quanto o simples trauma mecânico da agulha, näo säo capazes de produzir esclerose na veia marginal da orelha do coelho que seja estatisticamente significante.