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1.
Sensors (Basel) ; 23(1)2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36616889

RESUMO

Partial discharge (PD) diagnosis tests, including detecting, locating, and identifying, are used to trace defects or faults and assess the degree of aging in order to monitor the insulation condition of medium- and high-voltage power cables. In this context, an experimental evaluation of three different printed circuit board (PCB)-based inductive sensor topologies, with spiral, non-spiral, and meander shapes, is performed. The aim is to assess their capabilities for PD detection along a transmission power cable. First, simulation and experimental characterization are carried out to determine the equivalent electrical circuit and the quality factor of the three sensors. PD activity was studied in the lab on a 10-m-long defective MVAC cable. The three PCB-based sensors were tested in three different positions: directly on the defective cable (P1), at a separation distance of 10 cm to 3 m (P2), and on the ground line (P3). For the three positions, all sensors' outputs present a damped sine wave signal with similar frequencies and durations. Experimental results showed that the best sensitivity was given by the non-spiral inductor, with a peak voltage of around 500 mV in P1, 428 mV in P2, and 45 mV in P3, while the meander sensor had the lowest values, which were approximately 80 mV in P1. The frequency spectrum bandwidth of all sensors was between 10 MHz and 45 MHz. The high sensitivity of the non-spiral inductor could be associated with its interesting properties in terms of quality factor and SFR, which are due to its very low resistivity. To benchmark the performance of the designed three-loop sensors, a comparison with a commercial high-frequency current transformer (HFCT) is also made.

2.
J Food Sci Technol ; 58(12): 4685-4692, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33487735

RESUMO

Wine fractionation is an old practice widely applied for many reasons, including the production of food-grade alcohol and spirits, alcohol-reduced wines and beverages, functional products, and aromas. The purpose is the need to satisfy different lifestyles and legal constraints. The raw material, usually called industrial wine, includes wine overproduction and wine not used as such: mainly table wine, the fermented juice of unsold table grapes, and quality wine. Three technologies are currently in use: Vacuum distillation, Reverse osmosis in dialyzing mode, and the Spinning cone column. The process developed in this work results from the integration of a multistage reverse osmosis section operating in dialyzing mode, with the Atmospheric distillation of the permeate stream; the two most applied technologies for fractionating liquid mixtures. This process allows the fractionation of the wine into four products (the vegetation water, the azeotropic Ethanol, a concentrated aqueous solution of the solid extract, and a concentrated alcoholic solution of volatile aroma compounds) while preserving sensorial, nutritional and functional properties of the individual compounds. Then, the proper recombination of these products gives rise to a wide variety of wine-based products to meet the specifications of each market segment. The process is environmentally friendly and, in comparison with the competitors, is less energy-intensive, other than resilient and flexible regarding the production potentiality.

3.
Sensors (Basel) ; 19(5)2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30818866

RESUMO

The presence of a partial discharge phenomenon in an electrical apparatus is a warning signal that could determine the failure of the insulation system, terminating the service of the apparatus and/or the network. In this paper, an innovative partial discharge (PD) measurement instrument based on an antenna sensor is presented and analyzed. Being non-intrusive is one of the most relevant features of the sensor. The frequency response of the antenna sensor and the features to recognize different PD sources and automatically synchronize them with the supply voltage are described and discussed in details. The results show the performance of the instrument can make a fast and correct diagnosis of the health state of insulation systems.

4.
Ann Vasc Surg ; 44: 420.e11-420.e15, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28479469

RESUMO

BACKGROUND: Pink pulseless hand syndrome is a rare condition of vascular injury due to distal humerus fracture. It is characterized by radial and ulnar pulselessness in a complex of good hand perfusion which can remain pink and warm. The management and treatment of this condition is still very debated. METHODS: We report 4 cases of arm traumas which occurred in pediatric patients. In all cases, after the fixation of the fracture by the orthopedic surgeon, the clinical evaluation and duplex ultrasound demonstrated the so called "pink pulseless hand syndrome." RESULTS: We decided to proceed with an immediate surgical exploration and decompression followed by a prompt recovery of the pulsatility. Postoperative course was uneventful. At 3-year follow-up, the young patients have a normal hand function with no neurovascular damages and regular peripheral signals. CONCLUSIONS: Physical and ultrasound examination in cases of pediatric humerus fractures is important to show vascular complications before the orthopedic treatment which is usually privileged. In case of vascular damages, urgent surgical exploration can be the unique choice for a correct treatment.


Assuntos
Mãos/irrigação sanguínea , Hematoma/cirurgia , Fraturas do Úmero/complicações , Isquemia/cirurgia , Lesões do Sistema Vascular/cirurgia , Fatores Etários , Criança , Pré-Escolar , Descompressão Cirúrgica , Fixação Interna de Fraturas , Hematoma/diagnóstico , Hematoma/etiologia , Hematoma/fisiopatologia , Humanos , Fraturas do Úmero/diagnóstico por imagem , Fraturas do Úmero/cirurgia , Isquemia/diagnóstico por imagem , Isquemia/etiologia , Isquemia/fisiopatologia , Masculino , Recuperação de Função Fisiológica , Fluxo Sanguíneo Regional , Resultado do Tratamento , Ultrassonografia Doppler Dupla , Lesões do Sistema Vascular/diagnóstico por imagem , Lesões do Sistema Vascular/etiologia , Lesões do Sistema Vascular/fisiopatologia
5.
Cell Physiol Biochem ; 32(7): 86-95, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24429817

RESUMO

BACKGROUND: It has been reported that biologically active compounds extracted from Cnidaria venom may induce damage by oxidative stress. Erythrocytes are constantly exposed to oxidative stresses, which can contribute to sulphydril (SH-) group oxidation and cell membrane deformability accompanied with activation of K-Cl co-transport and inhibition of anion transport. In this regard, Band 3 protein is responsible for mediating the electroneutral exchange of chloride (Cl(-)) for bicarbonate (HCO3(-)), particularly in erythrocytes, where it is the most abundant membrane protein. The aim of this study was to elucidate the effect of crude venom extracted from Pelagia noctiluca nematocysts on Band 3 -mediated anion transport in human erythrocytes. METHODS: Erythrocytes were tested for SO4(2-) uptake, K(+) efflux, glutathione (GSH) levels and concentration of SH- groups. RESULTS: The rate constant of SO4(2-) uptake decreased progressively to 58% of control with increasing venom doses, and showed a 28% decrease after 2 mM NEM treatment. These effects can be explained by oxidative stress, which was reflected by decreased GSH levels in venom-treated erythrocytes. Hence, the decreased efficiency of anion transport may be due to changes in Band 3 structure caused by SH-group oxidation and reduced GSH concentration. In addition, an increased Cl(-)-dependent K(+) efflux was observed in venom-treated erythrocytes. CONCLUSION: Our results suggest that crude venom from Pelagia noctiluca alters cell membrane transport in human erythrocytes.


Assuntos
Venenos de Cnidários/toxicidade , Eritrócitos/efeitos dos fármacos , Transporte de Íons/efeitos dos fármacos , Potássio/metabolismo , Animais , Tamanho Celular/efeitos dos fármacos , Cloretos/metabolismo , Eritrócitos/metabolismo , Humanos , Nematocisto/química , Cifozoários/química
6.
Cell Mol Biol Lett ; 17(4): 586-97, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22941203

RESUMO

Our study concerns the effects of exposure to lead chloride on the morphology, K(+) efflux, SO(4)(-) influx and GSH levels of the human erythrocyte. Blood was collected in heparinized tubes and washed three times. The cells were suspended at 3% hematocrit and incubated for 1 h at 25°C in a medium containing increasing concentrations of lead chloride (0, 0.3, 0.5 and 1 µM). After incubation, the suspensions were centrifuged and the erythrocyte pellets were divided into three aliquots for testing. The results show: an increase in the permeability of erythrocytes treated with lead chloride with consequent damage and cellular death, especially in the presence of high concentrations; an increase in potassium ion efflux; alterations in the morphology and membrane structure of the red blood cells; and a decrease in sulphate uptake, due either to the oxidative effect of this compound on the band 3 protein, which loses its biological valence as a carrier of sulphate ions, or to a decrease in the ATP erythrocyte concentration. In conclusion, the exposure of erythrocytes to Pb(2+) ions leads to a reduction in the average lifetime of the erythrocytes and the subsequent development of anemia. These data are discussed in terms of the possible effect of lead on the reduction-oxidation systems of the cell. Oxidant agents, such as lead, are known to cross-link integral membrane proteins, leading to K/Cl-cotransport. The increased K(+) efflux affects the altered redox state.


Assuntos
Membrana Eritrocítica/efeitos dos fármacos , Glutationa/metabolismo , Chumbo/toxicidade , Sulfatos/metabolismo , Trifosfato de Adenosina/metabolismo , Proteína 1 de Troca de Ânion do Eritrócito/metabolismo , Ânions/química , Apoptose/efeitos dos fármacos , Permeabilidade da Membrana Celular/efeitos dos fármacos , Membrana Eritrocítica/metabolismo , Humanos , Cinética , Oxirredução , Potássio/metabolismo
7.
Angiology ; 69(1): 31-37, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29212353

RESUMO

Evidence suggests that psoriasis together with other cardiovascular (CV) risk factors is associated with increased vascular morbidity, but it is not clear whether psoriasis is an independent risk factor. Consecutive patients (n = 33; 35.6 ± 5.7 years; 13 females) with mild psoriasis (Psoriasis Area and Severity Index <10) without comorbidities and 33 healthy participants (36.3 ± 5.9 years; 15 females) were enrolled. Both groups underwent echocardiography, speckle tracking (2-dimensional strain echocardiography [2D-SE]), and pulse wave velocity (PWV) testing. Clinical and conventional echocardiographic characteristics were comparable between both groups. Global longitudinal strain (GLS) was significantly lower ( P = .002) in the psoriasis group (22.39% ± 2.28%) than in controls (24.15% ± 2.17%). The PWV was significantly lower ( P = .004) in controls (8.06 ± 1.68 m/s) than in the psoriasis group (9.23 ± 1.53 m/s). Significant correlations between GLS and disease duration ( r = -.66, P < .0001) and between GLS and patient age at diagnosis ( r = .48, P = .0043) were found. Psoriasis may be an independent CV risk factor, causing cardiac and vascular impairment. Both 2D-SE and PWV may be useful tools for the screening of CV risk in these patients.


Assuntos
Doenças Cardiovasculares/complicações , Sistema Cardiovascular/fisiopatologia , Psoríase/complicações , Rigidez Vascular/fisiologia , Adulto , Doenças Cardiovasculares/diagnóstico , Ecocardiografia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psoríase/diagnóstico , Análise de Onda de Pulso/métodos , Fatores de Risco , Disfunção Ventricular Esquerda/fisiopatologia
8.
Biosci Rep ; 27(4-5): 265-73, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17610155

RESUMO

The objective of this study was to assess the effects of nickel chloride on human and rainbow trout erythrocytes in vitro. The cells were incubated with 0, 0.5 and 1 mM nickel chloride for 1 h at pH 7.40 and 25 degrees C, then K(+) efflux, SO (4) (2-) uptake and GSH and GSSG concentrations were measured. In both kind of cells, "high concentration" nickel treatment increased KCl efflux with respect to the control. The SO (4) (2-) uptake was not significantly different at "low nickel concentration" but was lower in erythrocytes treated with 1 mM nickel chloride; the rate constant of SO (4) (2-) uptake decreased by 35% in human erythrocytes and by 44% in fish erythrocytes. Nickel chloride also acts on cellular metabolism and in particular on erythrocyte glutathione peroxidase with consequent increase in oxidative stress; the data show a significant decrease in intracellular GSH in both human (25%) and fish erythrocytes (18%) after treatment with nickel chloride, with concomitantly high GSSG concentrations and lower GSH/GSSG ratios.


Assuntos
Proteína 1 de Troca de Ânion do Eritrócito/metabolismo , Eritrócitos/efeitos dos fármacos , Níquel/farmacologia , Animais , Tamanho Celular , Glutationa/sangue , Humanos , Oncorhynchus mykiss , Oxirredução , Estresse Oxidativo , Potássio/metabolismo , Sulfatos/metabolismo
9.
Chir Ital ; 57(1): 77-85, 2005.
Artigo em Italiano | MEDLINE | ID: mdl-15832742

RESUMO

The aim of the study was to evaluate whether topical application of 0.2% glyceryl trinitrate ointment could reduce post-haemorrhoidectomy healing time and pain both at rest and during defecation. Thirty patients with grade III and IV haemorrhoids were included in the study and divided into two groups. All patients underwent Milligan-Morgan haemorrhoidectomy, and anorectal manometry was performed before surgery and after 5 and 30 days. In one group a placebo ointment was applied to the perianal wounds, while in the other group a 0.2% glyceryl trinitrate ointment was used. Maximum resting pressure was reduced in the glyceryl trinitrate group and increased in the placebo group after 5 days. Postoperative pain both at rest and during defecation, and the time to healing and return to normal activity were significantly reduced in the glyceryl trinitrate group, whilst analgesic consumption was similar. An elevated incidence of headache was observed In the glyceryl trinitrate group. Topical application of glyceryl trinitrate was effective in reducing postoperative pain and healing time, but the substantial incidence of side effects may limit its extensive use.


Assuntos
Hemorroidas/cirurgia , Nitroglicerina/uso terapêutico , Dor Pós-Operatória/tratamento farmacológico , Vasodilatadores/uso terapêutico , Cicatrização/efeitos dos fármacos , Administração Cutânea , Adolescente , Adulto , Método Duplo-Cego , Feminino , Cefaleia/induzido quimicamente , Humanos , Masculino , Pessoa de Meia-Idade , Nitroglicerina/efeitos adversos , Pomadas , Dor Pós-Operatória/etiologia , Resultado do Tratamento , Vasodilatadores/efeitos adversos
10.
Chir Ital ; 57(4): 471-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16060185

RESUMO

Wound healing is a complex process involving interaction between different cell types, such as growth factors. Among these, vascular endothelial growth factors (VEGF) and basic fibroblast growth factors (b-FGF) are the most important. The aim of this study was to assess the production of VEGF and b-FGF in wound drainage fluid from patients undergoing incisional abdominal hernia repair. Ten female patients with abdominal midline incisional hernia undergoing surgical repair were included in this study. In all cases a closed suction drain was placed in the wound below the fascia and removed on postoperative day 4. Wound fluid was collected on the I, II, III and IV day and its amount at each time was recorded. VEGF and b-FGF production were evaluated as the quantity produced in 24 hours. In all patients the amount of drainage fluid from the surgical wound was highest on the I day after surgery, after which there was a significant reduction. VEGF production increased progressively after the operation proving significantly higher only on the IV day. The amount of b-FGF, in contrast, was higher on the I day, decreasing thereafter on the following postoperative days. Analysis of the production of growth factors in the drainage fluid has enabled us to better assess the events that occur following surgical wounds and has confirmed the physiology of the healing process and the possible use of these factors in modulating positive healing.


Assuntos
Drenagem , Exsudatos e Transudatos , Fator 2 de Crescimento de Fibroblastos/biossíntese , Hérnia Ventral/cirurgia , Fator A de Crescimento do Endotélio Vascular/biossíntese , Cicatrização , Adulto , Análise de Variância , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Pessoa de Meia-Idade , Período Pós-Operatório
13.
Dis Colon Rectum ; 49(11): 1741-8, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16990976

RESUMO

PURPOSE: The maximum resting pressure in the anal canal is greatly raised after hemorrhoidectomy. This increase is likely to be the cause of postoperative pain, which is still the most troublesome early problem after hemorrhoidectomy. This study was designed to compare, after hemorrhoidectomy, the effects of intrasphincter injection of botulinum toxin vs. application of glyceryl trinitrate ointment in improving wound healing and reducing postoperative pain at rest or during defecation. METHODS: Thirty patients with hemorrhoids of third and fourth degree were included in the study and randomized in two groups. Anorectal manometry was performed preoperatively and 5 and 40 days after hemorrhoidectomy. One group received one injection containing 20 IU of botulinum toxin, whereas the other an application of 300 mg of 0.2 percent glyceryl trinitrate ointment three times daily for 30 days. RESULTS: Five days after hemorrhoidectomy, maximum resting pressure was significantly reduced compared with baseline values in both groups (85 +/- 15 vs. 68 +/- 11 mmHg for the group treated with botulinum toxin, 87 +/- 11 vs. 78 +/- 11 mmHg for the group treated with glyceryl trinitrate ointment). Overall analysis of postoperative pain at rest showed a significant reduction in the botulinum toxin group vs. glyceryl trinitrate group, whereas pain during defecation and time of healing were similar. Adverse effects, such as headaches, were observed only in the glyceryl trinitrate group. Forty days after hemorrhoidectomy in the glyceryl trinitrate group, maximum resting pressure values were similar to preoperative ones, whereas the values were still reduced in the botulinum toxin group. CONCLUSIONS: A single intrasphincter injection of botulinum toxin was more effective and safer than repeated applications of glyceryl trinitrate in reducing early postoperative pain at rest but not during defecation.


Assuntos
Toxinas Botulínicas Tipo A/uso terapêutico , Hemorroidas/cirurgia , Fármacos Neuromusculares/uso terapêutico , Nitroglicerina/uso terapêutico , Dor Pós-Operatória/prevenção & controle , Adulto , Defecação , Feminino , Humanos , Injeções , Masculino , Manometria , Pomadas , Medição da Dor , Descanso , Resultado do Tratamento
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