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1.
Tech Coloproctol ; 26(8): 627-636, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35334004

RESUMO

BACKGROUND: The aim of the present study was to evaluate the efficacy and safety of 3% polidocanol foam for treating 2nd-degree haemorrhoids. METHODS: A multicentre, open-label, single-arm, phase 2 trial involving 10 tertiary referral centres for haemorrhodal disease (HD) was performed. Between January and June 2019, patients with 2nd-degree haemorrhoids were prospectively included in this study. The primary outcome was to establish the success rate after one sclerotherapy session in terms of complete resolution of bleeding episodes one week after the injection. The Hemorrhoidal Disease Symptom Score (HDSS), the Short Health Scale for HD (SHS-HD) score and the Vaizey incontinence score were used to assess symptoms and their impact on quality of life and continence. Pain after the procedure, subjective symptoms and the amount and type of painkillers used were recorded. Patients were followed up for 1 year. RESULTS: There were 183 patients [111 males; 60.7%, mean age 51.3 ± 13.5 (18-75) years]. Complete resolution of bleeding was reached in 125/183 patients (68.3%) at 1 week and the recurrence rate was 12% (15/125). Thirteen patients (7.4%) underwent a second sclerotherapy session, while only 1 patient (1.8%) had to undergo a third session. The overall 1-year success rate was 95.6% (175/183). The HDSS and the SHS score significantly improved from a median preoperative value of 11 and 18 to 0 and 0, respectively (p < 0.001). There were 3 episodes of external thrombosis. No serious adverse events occurred. CONCLUSIONS: Sclerotherapy with 3% polidocanol foam is a safe, effective, painless, repeatable and low-cost procedure in patients with bleeding haemorrhoids.


Assuntos
Hemorroidas , Polidocanol , Escleroterapia , Adolescente , Adulto , Idoso , Feminino , Hemorroidas/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Polidocanol/efeitos adversos , Qualidade de Vida , Escleroterapia/efeitos adversos , Escleroterapia/métodos , Resultado do Tratamento , Adulto Jovem
2.
Sleep Breath ; 26(2): 879-885, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34302609

RESUMO

PURPOSE: Local and systemic inflammatory markers and pro-inflammatory cytokines are increased in children with obstructive sleep apnea syndrome (OSAS). Therefore, systemic or topical anti-inflammatory agents are used to treat this syndrome. We evaluated the treatment with systemic corticosteroids in children with severe OSAS and adenotonsillar hypertrophy before surgery. METHODS: This was an unblinded open label study. Children with severe OSAS (diagnosed through polysomnography, obstructive apnea-hypopnea index [AHI] > 10 eV/h) were recruited. Exclusion criteria included age < 3 years, history of acute or chronic cardiorespiratory or neuromuscular or metabolic disease; major craniofacial abnormalities; and chromosomal syndromes and epilepsy. Computer-generated random numbers were used for simple randomization of subjects. All children were treated with intranasal beclomethasone spray, and 15 children additionally received oral betamethasone and 0.1 mg/kg per day for 7 days. Sleep clinical record (SCR) and pulsoximetry were performed before and after 7 days in all children. RESULTS: Among 28 children with severe OSAS mean age was 4.5 ± 1.8 years, AHI 20.4 ± 1.8 eV/h). In children treated with intranasal and oral corticosteroids, mean (95.3 ± 1.1 vs 97.0 ± 0.8%, p = 0.0001) and minimum oxygen saturation (78.8 ± 6.3 vs 89.2 ± 4.2, p = 0.001) improved, and the SCR score (12.6 ± 1.2 vs 8.3 ± 1.1, p = 0.0001) was reduced. Children treated only with intranasal beclomethasone spray showed no differences in outcome measures before and after treatments. When we considered the oximetry measures, after corticosteroid treatment, we obtained statistical differences between the 2 groups (p < 0.01). CONCLUSIONS: These results seem to suggest that a short course of oral betamethasone could be useful to treat children with severe OSAS and adenotonsillar hypertrophy waiting for surgery.


Assuntos
Beclometasona , Apneia Obstrutiva do Sono , Beclometasona/uso terapêutico , Betametasona , Criança , Pré-Escolar , Humanos , Hipertrofia , Polissonografia , Apneia Obstrutiva do Sono/diagnóstico
3.
Tech Coloproctol ; 25(12): 1269-1280, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34176001

RESUMO

Pilonidal disease (PD) is a relatively common, benign but challenging condition of the natal cleft. This consensus statement was drawn up by a panel of surgeons, identified by the Italian Society of Colorectal Surgery (SICCR) as having a "special interest" in PD, with the aim of recommending the best therapeutic options according to currently available scientific evidence. A three-step modified-Delphi process was adopted, implying: (1) choice of the panelists; (2) development of a discussion outline and of target issues; and (3) a detailed systematic review of the current literature. The agreement/disagreement level was scored on a five-point Likert scale as follows: "A + : strongly agree; A-: agree; N: unsure/no opinion; D-: disagree; D + : strongly disagree. Each panelist contributed to the production of this manuscript, and the final recommendations were reviewed by the Clinical Practice Guidelines Committee.


Assuntos
Cirurgia Colorretal , Procedimentos Cirúrgicos do Sistema Digestório , Consenso , Técnica Delphi , Humanos , Itália , Guias de Prática Clínica como Assunto
4.
Nat Commun ; 11(1): 4105, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32796852

RESUMO

The transport properties of iron under Earth's inner core conditions are essential input for the geophysical modelling but are poorly constrained experimentally. Here we show that the thermal and electrical conductivity of iron at those conditions remains high even if the electron-electron-scattering (EES) is properly taken into account. This result is obtained by ab initio simulations taking into account consistently both thermal disorder and electronic correlations. Thermal disorder suppresses the non-Fermi-liquid behavior of the body-centered cubic iron phase, hence, reducing the EES; the total calculated thermal conductivity of this phase is 220 Wm-1 K-1 with the EES reduction not exceeding 20%. The EES and electron-lattice scattering are intertwined resulting in breaking of the Matthiessen's rule with increasing EES. In the hexagonal close-packed iron the EES is also not increased by thermal disorder and remains weak. Our main finding thus holds for the both likely iron phases in the inner core.

6.
Colorectal Dis ; 18(11): 1094-1100, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26969880

RESUMO

AIM: Many different surgical techniques have been reported for the surgical treatment of full-thickness external rectal prolapse. Perianal stapled prolapse resection (PSP) is a relatively newly reported technique for full thickness external rectal prolapse. The aim of this prospective multicentre study was to evaluate the results of this procedure. METHOD: Consecutive patients who underwent a PSP resection for full-thickness external rectal prolapse at five centres were recruited to the study. Median operating time, hospital stay, complications, recurrence and functional results according to the Wexner Incontinence Scale and obstructive defaecation syndrome score were recorded. RESULTS: There were 27 patients treated by PSP. The median Wexner incontinence score improved from 10 presurgery to 5 after surgery (P < 0.001); the median obstructed defaecation syndrome score improved from 12 presurgery to 5 (range 4-10) after surgery (P < 0.001). A laparoscopically assisted procedure was performed in three patients (11.1%). The median number of cartridges used was six (range four to nine). The median operating time was 48 min. Early complications occurred in six patients (22.2%) and late complications in two (7.4%). The median length of hospital stay was 5 days. The recurrence rate at a median follow-up of 30.3 months was 14.8%. CONCLUSION: PSP appears to be an easy, fast and safe procedure. Early functional results are good. The recurrence rate compares favourably with other perineal procedures like the Delorme or the Altemeier operations. Long-term functional results need to be investigated further.


Assuntos
Prolapso Retal/cirurgia , Grampeamento Cirúrgico/métodos , Idoso , Idoso de 80 Anos ou mais , Constipação Intestinal/etiologia , Constipação Intestinal/cirurgia , Defecação/fisiologia , Incontinência Fecal/etiologia , Incontinência Fecal/cirurgia , Feminino , Seguimentos , Humanos , Obstrução Intestinal/etiologia , Obstrução Intestinal/cirurgia , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Períneo/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Período Pós-Operatório , Período Pré-Operatório , Estudos Prospectivos , Prolapso Retal/complicações , Prolapso Retal/fisiopatologia , Recidiva , Índice de Gravidade de Doença , Resultado do Tratamento
8.
Am J Ther ; 23(1): e159-71, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-24858335

RESUMO

The different aspects that contribute to quality of life in patients with diabetes mellitus, such as mood, are of great importance for the treatment of this disease. These aspects not only influence the well-being of patients but also influence treatment adherence, therefore affecting the course of the disease. A panel of experts from Argentina, Chile, and Uruguay performed a review of the main aspects affecting quality of life in patients with diabetes: physical activity, mood disorders, and sexual activity. The consensus of the panel was that physical activity is important in the treatment of patients with diabetes because it reduces morbidity, mortality, and disease complications, and it should be performed on a regular basis, bearing in mind the patient's characteristics. Increased physical activity is associated with better glycemic control, and in individuals with glucose intolerance, it delays progression toward diabetes. In patients with diabetes, there is a high prevalence of depression, which can influence treatment adherence. Therefore, early detection of depression is essential to improve the course of diabetes. Regarding sexual activity, erectile dysfunction may be a significant sign in the case of suspected diabetes and the early diagnosis of vasculopathy in patients with diabetes. In conclusion, greater emphasis should be placed on improving patient knowledge, early detection, and multidisciplinary approaches to deal with the aspects of diabetes that affect patients' quality of life.


Assuntos
Depressão/etiologia , Diabetes Mellitus/psicologia , Exercício Físico , Qualidade de Vida , Disfunções Sexuais Psicogênicas/etiologia , Depressão/diagnóstico , Depressão/terapia , Diabetes Mellitus/terapia , Humanos , Fatores de Risco , Disfunções Sexuais Psicogênicas/diagnóstico , Disfunções Sexuais Psicogênicas/terapia
9.
Tech Coloproctol ; 19(10): 607-13, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26377583

RESUMO

The Italian Society of Colorectal Surgery (SICCR.) has prepared clinical practice guidelines to help its members to optimize the treatment of pilonidal disease, a very common condition, especially among young people, and therefore of great importance on a socioeconomic level. The SICCR committee of experts on pilonidal disease analyzed the international literature and evaluated current evidence. Nonoperative management includes gluteal cleft shaving, laser epilation as well as fibrin glue and phenol injection: reported healing rates and recurrence incidence are satisfactory but the majority of studies are small series with low-quality evidence. Surgical therapy which can be divided into two categories: excision of diseased tissue with primary closure using different techniques or excision with healing by secondary intention. On the whole, no clear benefit is demonstrated for one technique over the other.


Assuntos
Cirurgia Colorretal/normas , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Gerenciamento Clínico , Seio Pilonidal/terapia , Anti-Infecciosos Locais/uso terapêutico , Nádegas/patologia , Nádegas/cirurgia , Drenagem , Adesivo Tecidual de Fibrina/uso terapêutico , Remoção de Cabelo/métodos , Humanos , Itália , Fenol/uso terapêutico , Seio Pilonidal/classificação , Recidiva , Adesivos Teciduais/uso terapêutico
10.
Seizure ; 25: 181-3, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25457448

RESUMO

PURPOSE: To determine whether celiac children are at risk for EEG-neurological features and sleep disordered breathing (SDB), and whether an appropriate gluten-free diet (GFD) influences these disorders. METHODS: We consecutively enrolled 19 children with a new biopsy-proven celiac disease (CD) diagnosis. At CD diagnosis and after 6 months of GFD, each patient underwent a general and neurological examination, an electroencephalogram, a questionnaire about neurological features, and a validated questionnaire about SDB: OSA (obstructive sleep apnea) scores<0 predict normality; values>0 predict OSA. RESULTS: At CD diagnosis, 37% of patients complained headache that affected daily activities and 32% showed positive OSA score. The EEG examinations revealed abnormal finding in 48% of children. After 6 months of GFD headache disappeared in 72% of children and EEG abnormalities in 78%; all children showed negative OSA score. CONCLUSION: According to our preliminary data, in the presence of unexplained EEG abnormalities and/or other neurological disorders/SDB an atypical or silent CD should also be taken into account.


Assuntos
Encéfalo/fisiopatologia , Doença Celíaca/dietoterapia , Doença Celíaca/fisiopatologia , Dieta Livre de Glúten , Síndromes da Apneia do Sono/dietoterapia , Síndromes da Apneia do Sono/fisiopatologia , Adolescente , Criança , Pré-Escolar , Eletroencefalografia , Feminino , Cefaleia/dietoterapia , Cefaleia/fisiopatologia , Humanos , Masculino , Estudos Prospectivos , Inquéritos e Questionários , Resultado do Tratamento
11.
Br Poult Sci ; 55(2): 215-20, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24423730

RESUMO

1. The protective effect of a natural Brazilian calcium montmorillonite (CaMont) against aflatoxins was studied in broiler chickens. 2. A total of 1056-d-old Cobb male broilers were housed in experimental pens (22 chickens per pen) for 42 d. Three levels of CaMont (0, 2.5 and 5 g/kg) and two levels of aflatoxins (0 and 3 mg/kg) were assayed. Each treatment had 8 replicate pens of 22 broiler chickens each. 3. Of all the chickens tested in the experiment, the ones treated with aflatoxins were the most adversely affected. CaMont treatment at concentrations of 2.5 and 5 g/kg improved body weight of chickens at 42 d of age by 13.3% and 22.7%, increased daily feed intake by 9.7% and 24.7%, and improved the productive efficiency index of chickens by 53% and 66.5%, respectively. 4. Dietary CaMont positively affected parameters such as weight of liver, heart and gizzard; however, serum potassium concentration decreased by 15.3% compared with that of chickens given only the aflatoxin-contaminated diet. 5. CaMont did not cause adverse effects in chickens that did not receive aflatoxins. 6. CaMont at pH 8.5 partially reduced the toxic effects of aflatoxins in broilers when included at levels of 2.5 and 5 g/kg in the diet.


Assuntos
Aflatoxinas/metabolismo , Bentonita/farmacologia , Peso Corporal/efeitos dos fármacos , Cálcio da Dieta/farmacologia , Galinhas/metabolismo , Tamanho do Órgão/efeitos dos fármacos , Aflatoxinas/toxicidade , Ração Animal/análise , Animais , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Masculino , Distribuição Aleatória
12.
Sci Rep ; 3: 2430, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23938361

RESUMO

We show that bimetallic surface alloying provides a viable route for governing the interaction between graphene and metal through the selective choice of the elemental composition of the surface alloy. This concept is illustrated by an experimental and theoretical characterization of the properties of graphene on a model PtRu surface alloy on Ru(0001), with a concentration of Pt atoms in the first layer between 0 and 50%. The progressive increase of the Pt content determines the gradual detachment of graphene from the substrate, which results from the modification of the carbon orbital hybridization promoted by Pt. Alloying is also found to affect the morphology of graphene, which is strongly corrugated on bare Ru, but becomes flat at a Pt coverage of 50%. The method here proposed can be readily extended to several supports, thus opening the way to the conformal growth of graphene on metals and to a full tunability of the graphene-substrate interaction.


Assuntos
Ligas/química , Cristalização/métodos , Grafite/química , Nanopartículas Metálicas/química , Adesividade , Adsorção , Teste de Materiais , Propriedades de Superfície
13.
Arq. bras. med. vet. zootec ; 63(5): 1229-1232, out. 2011. tab
Artigo em Inglês | LILACS | ID: lil-605851

RESUMO

Avaliou-se a atividade antimicrobiana dos óleos essenciais (OE) de Origanum vulgare (orégano), Thymus vulgaris (tomilho), Lippia graveolens (lipia), Zingiber officinale (gengibre), Salvia officinalis (sálvia), Rosmarinus officinalis (alecrim) e Ocimum basilicum (manjericão), e de suas frações majoritárias, carvacrol e timol, frente a 32 isolados de Staphylococcus spp, oriundos de rebanhos leiteiros bovinos. A concentração inibitória mínima (CIM) e a concentração bactericida mínima foram determinadas por meio da técnica de microdiluição em caldo. Orégano, tomilho e lípia (Orégano Mexicano) apresentaram atividade antimicrobiana similar, médias geométrica de CIM de 1600µg mL-1; 1564µg mL-1; 1562µg mL-1, respectivamente, no entanto menos ativos que carvacrol, 584µg mL-1 e thymol, 427µg mL-1. Isolados com diferentes perfis de susceptibil idade aos antimicrobianos usados no tratamento de mastite bovina, quando subagrupados, foram inibidos por concentrações semelhantes de OE . Estes resultados confirmam a atividade antimicrobiana de OE e algumas frações majoritárias.


Assuntos
Animais , Bovinos , Anti-Infecciosos , Mastite Bovina , Ocimum basilicum , Origanum , Thymus serpyllum/uso terapêutico , Timol/uso terapêutico
14.
Phys Rev Lett ; 106(21): 216101, 2011 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-21699318

RESUMO

We report on a novel approach to determine the relationship between the corrugation and the thermal stability of epitaxial graphene grown on a strongly interacting substrate. According to our density functional theory calculations, the C single layer grown on Re(0001) is strongly corrugated, with a buckling of 1.6 Å, yielding a simulated C 1s core level spectrum which is in excellent agreement with the experimental one. We found that corrugation is closely knit with the thermal stability of the C network: C-C bond breaking is favored in the strongly buckled regions of the moiré cell, though it requires the presence of diffusing graphene layer vacancies.

15.
J Phys Condens Matter ; 21(9): 095004, 2009 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-21817377

RESUMO

The role of steps in the dissociation of molecules on metal surfaces has been extensively investigated in the past. In particular, both theoretical calculations and experimental results for H(2) dissociation on transition metal (TM) surfaces show that steps can significantly increase the reactivity, leading to higher metal-H binding energies and lower activation energies. Here we have used density functional theory (DFT) with the generalized gradient approximation (GGA) to investigate the role of steps on the Mg(0001) surface in the dissociation of H(2) and the binding of H to the metal surface. Our results follow those found for TM surfaces as far as H adsorption energies are concerned, namely that adsorption energies are higher near the steps. However, we find that the activation energy for the dissociation of hydrogen is hardly affected by the presence of steps, with a DFT-GGA value of 0.85 eV, only marginally lower than the value 0.87 eV found on the flat Mg(0001) surface.

16.
J Chem Phys ; 128(9): 094703, 2008 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-18331106

RESUMO

It is well-known, both theoretically and experimentally, that alloying MgH(2) with transition elements can significantly improve the thermodynamic and kinetic properties for H(2) desorption, as well as the H(2) intake by Mg bulk. Here, we present a density functional theory investigation of hydrogen dissociation and surface diffusion over a Ni-doped surface and compare the findings to previously investigated Ti-doped Mg(0001) and pure Mg(0001) surfaces. Our results show that the energy barrier for hydrogen dissociation on the pure Mg(0001) surface is high, while it is small/null when NiTi are added to the surface as dopants. We find that the binding energy of the two H atoms near the dissociation site is high on Ti, effectively impeding diffusion away from the Ti site. By contrast, we find that on Ni, the energy barrier for diffusion is much reduced. Therefore, although both Ti and Ni promote H(2) dissociation, only Ni appears to be a good catalyst for Mg hydrogenation, allowing diffusion away from the catalytic sites. Experimental results corroborate these theoretical findings, i.e., faster hydrogenation of the Ni-doped Mg sample as opposed to the reference Mg- or Ti-doped Mg.


Assuntos
Hidrogênio/química , Magnésio/química , Níquel/química , Titânio/química , Ligas , Difusão , Semicondutores , Propriedades de Superfície
17.
Eur J Appl Physiol ; 95(4): 321-6, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16096843

RESUMO

The aim of the study was to investigate the relationship between a fatigue-induced increase of perceived exertion in the neck with a decrease of mean power frequency (MPF) in the surface electromyography (sEMG) signal during repeated shoulder elevation endurance tasks. About Thirty-two healthy women (age range 20-62) performed two maximum 6-min shoulder elevation endurance tasks at 30% of their maximal voluntary contraction (MVC) level, separated by a rest of 6 min. During these exercises, perceived exertion was estimated using the Borg scale (range 0-10), whereas the MPF of the sEMG signal from the upper trapezius was simultaneously detected. Linear regression analysis was applied over time for each trial and subject for both MPF and Borg scale rating values. The MPF was normalized by the intercept of the linear regression analysis. The resulting slopes of normalized mean power frequency (nMPF) and Borg scale rating were correlated with each other by linear regression for both trials. In order to investigate the individual behavior of fatigue effects between trials, Delta (trial 2-trial 1) slopes of nMPF and Borg scale ratings were calculated for each subject. These slopes of nMPF and Borg scale ratings were correlated with each other as well by linear regression. The increase of Borg scale ratings, as well as the decrease of nMPF, were significantly higher in trial 2 than trial 1 (P<0.01). The results show a linear correlation between slopes of nMPF and Borg scale ratings for both trials 1 and 2 (r=0.76, P<0.01). Trial-to-trial slopes (Delta (trial 2-trial 1)) of nMPF and Borg scale rating, were also significantly correlated (r=0.68, P<0.05). Thus, the individually sensed increase of perceived exertion in the neck during trial 2 was accompanied by a simultaneously higher detected decrease of nMPF. These findings indicate a close relationship between subjective perception of exertion in the neck and objectively assessed muscle fatigue of the upper trapezius.


Assuntos
Fadiga Muscular , Músculo Esquelético/fisiologia , Músculos/fisiologia , Resistência Física , Ombro/fisiologia , Adulto , Eletromiografia , Feminino , Humanos , Contração Isométrica/fisiologia , Pessoa de Meia-Idade , Esforço Físico , Postura , Análise de Regressão
18.
G Ital Med Lav Ergon ; 27(1): 88-95, 2005.
Artigo em Italiano | MEDLINE | ID: mdl-15915680

RESUMO

Neuromuscular problems reduce working ability of aging workers, and increase cases of work loss and accidents. For this reason, elderly people throughout Europe are forced into early retirement, and fail to be self-supporting. There is a need to identify and monitor work related neuromuscular disorders in order to reduce their consequences by monitoring the most vulnerable individuals, identify the determinants of neuromuscular aging related to occupational conditions, prevent pathologies and their evolution. Preliminary results show the possibility of identification of neuromuscular problems through non invasive techniques, some of which, recently developed within the SENIAM and PROCID Concerted Actions, can provide quantitative indices of neuromuscular performance. Substantial field tests and training initiatives are required to demonstrate if these techniques can be used outside the research labs, if there may be a European market in the fields of ergonomics and occupational health, and if they can be routinely used with standardized methodology to monitor the relationship between occupational and neuromuscular system conditions in the working environment. The objective of the European Project Neuromuscular assessment in the Elderly Worker (NEW) is to answer these questions.


Assuntos
Avaliação Geriátrica , Doenças Neuromusculares/diagnóstico , Doenças Profissionais/diagnóstico , Idoso , Desenho de Equipamento , Ergonomia/instrumentação , Europa (Continente) , Humanos
19.
Med Biol Eng Comput ; 42(4): 455-66, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15320454

RESUMO

The use of mono- and bi-dimensional electromyogram (EMG) electrode arrays for the assessment of the neuromuscular system can provide an insight into muscle physiology not achieved with classical bipolar surface EMG. Among the advantages of multichannel EMG detection, there is a) the possibility of estimating muscle fibre conduction velocity, even during motor tasks, and b) the possibility to increase the number of detection points on a muscle, improving the performance of pattern-based EMG decomposition methods. For these reasons, the development and use of multichannel surface EMG devices and techniques were chosen as the primary goals within the European RTD Project 'Neuromuscular assessment in the elderly worker' (NEW). The specific requirements of Project NEW called for the availability of a user-friendly, small-sized EMG acquisition system for field use, suitable for multichannel EMG recording using electrode arrays from one or more muscles. A market survey established that none of the commercially available EMG acquisition systems featured all the desired specifications, nor could they be easily adapted for specific use. The paper describes the design of an innovative acquisition system for long-term multichannel EMG recording fulfilling these requirements and comprising adhesive electrode arrays for artifact-free EMG acquisition during work activity and a portable, user-friendly, battery-powered acquisition system for multichannel EMG recording and storage on a removable PCMCIA card. The system has been used extensively within Project NEW for laboratory and field tests and can find applications in other fields of basic and applied research, including ergonomics, occupational and sports medicine.


Assuntos
Eletrodos , Eletromiografia/instrumentação , Assistência Ambulatorial/métodos , Eletrônica Médica/instrumentação , Desenho de Equipamento , Humanos , Monitorização Fisiológica/instrumentação
20.
Muscle Nerve ; 29(6): 823-33, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15170615

RESUMO

Muscle-fiber conduction velocity (CV) was estimated from surface electromyographic (EMG) signals during isometric contractions and during short (150-200 ms), explosive, dynamic exercises. Surface EMG signals were recorded with four linear adhesive arrays from the vastus lateralis and medialis muscles of 12 healthy subjects. Isometric contractions were at linearly increasing force from 0% to 100% of the maximum. The dynamic contractions consisted of explosive efforts of the lower limb on a sledge ergometer. For the explosive contractions, muscle-fiber CV was estimated in seven time-windows located along the ascending time interval of the force. There was a significant correlation between CV values during the isometric ramp and explosive contractions (R = 0.75). Moreover, CV estimates increased significantly from (mean +/- SD) 4.32 +/- 0.46 m/s to 4.97 +/- 0.45 m/s during the increasing-force explosive task. It was concluded that CV can be estimated reliably during dynamic tasks involving fast limb movements and that, in these contractions, it may provide important information on motor-unit control properties.


Assuntos
Eletromiografia/métodos , Contração Muscular/fisiologia , Fibras Musculares Esqueléticas/fisiologia , Adulto , Eletromiografia/instrumentação , Humanos , Perna (Membro) , Masculino , Modelos Biológicos , Neurônios Motores/fisiologia , Músculo Esquelético/citologia , Músculo Esquelético/inervação , Músculo Esquelético/fisiologia
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