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1.
Talanta ; 265: 124810, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37364384

RESUMO

In this work, an electrochemical method was developed for rapid and sensitive detection of hydroxychloroquine (HCQ), an ineffective candidate drug for COVID-19 treatment however widely consumed during the pandemic, in aqueous samples using a multi-walled carbon nanotubes (MWCNT) film produced through the interfacial method on the indium tin oxide electrode (ITO). According to Raman spectroscopy, X-ray diffraction, UV-vis spectroscopy, Energy-dispersive X-ray spectroscopy, scanning electron microscopy, and atomic force microscopy, the interfacial method produces homogeneous thin films of carbon nanotubes on the substrate surface, which keep connected to the surface forming a three-dimensional microporous structure. The electrochemical behavior and oxidation kinetics of HCQ were also investigated in the MWCNT film. The sensor showed a 7 times higher oxidation current for (69.88 µA) for HCQ than the ITO electrode (9.33 µA) due to the electrocatalytic properties MWCNTs. The ITO-modified electrode was assembled on a portable 3D-printed batch-injection cell for the amperometric detection of HCQ. The oxidation peak current of HCQ is linearly proportional to the concentrations of HCQ ranging from 1.0 to 100.0 µmol L-1, with a limit of detection of 0.27 µmol L-1. Water samples (river and tap water) were spiked with HCQ, without the need for dispendious pretreatment (except filtration), and analyzed by the portable system, revealing the detection of HCQ with the recovery of 92.0%-99.8%, which suggested the great potential for real environmental monitoring application.

2.
Biosensors (Basel) ; 13(6)2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37367011

RESUMO

A rapid and simple method for the amperometric determination of glucose using a nanocomposite film of nickel oxyhydroxide and multi-walled carbon nanotube (MWCNTs) was evaluated. The NiHCF)/MWCNT electrode film was fabricated using the liquid-liquid interface method, and it was used as a precursor for the electrochemical synthesis of nickel oxy-hydroxy (Ni(OH)2/NiOOH/MWCNT). The interaction between nickel oxy-hydroxy and the MWCNTs provided a film that is stable over the electrode surface, with high surface area and excellent conductivity. The nanocomposite presented an excellent electrocatalytic activity for the oxidation of glucose in an alkaline medium. The sensitivity of the sensor was found to be 0.0561 µA µmol L-1, and a linear range from 0.1 to 150 µmol L-1 was obtained, with a good limit of detection (0.030 µmol L-1). The electrode exhibits a fast response (150 injections h-1) and a sensitive catalytic performance, which may be due to the high conductivity of MWCNT and the increased active surface area of the electrode. Additionally, a minimal difference in the slopes for ascending (0.0561 µA µmol L-1) and descending (0.0531 µA µmol L-1) was observed. Moreover, the sensor was applied to the detection of glucose in artificial plasma blood samples, achieving values of 89 to 98% of recovery.


Assuntos
Nanotubos de Carbono , Níquel , Glucose , Oxirredução , Eletrodos , Impressão Tridimensional , Técnicas Eletroquímicas/métodos
3.
Mikrochim Acta ; 189(5): 188, 2022 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-35404013

RESUMO

A laser-induced graphene (LIG) surface modified with Prussian blue (iron hexacyanoferrate) is demonstrated as a novel electrochemical sensing platform for the sensitive and selective detection of hydrogen peroxide. Electrochemical Prussian blue (PB) modification on porous graphene films engraved by infrared laser over flexible polyimide was accomplished. Scanning electron microscopy images combined with Raman spectra confirm the formation of porous graphene and homogenous electrodeposition of PB over this porous surface. Electrochemical impedance spectroscopy reveals a substantial decrease in the resistance to charge transfer values (from 395 to 31.4 Ω) after the PB insertion, which confirms the formation of a highly conductive PB-graphene composite. The synergistic properties of PB and porous graphene were investigated for the constant monitoring of hydrogen peroxide at 0.0 V vs. Ag|AgCl|KCl(sat.), under high-flow injections (166 µL s-1) confirming the high stability of the modified surface and fast response within a wide linear range (from 1 to 200 µmol L-1). Satisfactory detection limit (0.26 µmol L-1) and selectivity verified by the analysis of complex samples confirmed the excellent sensing performance of this platform. We highlight that the outstanding sensing characteristics of the developed sensor were superior in comparison with other PB-based or LIG-based electrochemical sensors reported for hydrogen peroxide detection.


Assuntos
Grafite , Técnicas Eletroquímicas/métodos , Eletrodos , Ferrocianetos , Grafite/química , Peróxido de Hidrogênio/análise , Lasers
4.
Rev Neurol ; 70(12): 453-460, 2020 Jun 16.
Artigo em Espanhol | MEDLINE | ID: mdl-32500524

RESUMO

INTRODUCTION: Spasticity is a frequent clinical sign in people with neurological diseases that affects mobility and causes serious complications: pain, joint limitation, muscular contractions and bed sores, which have a significant effect on the individual's functionality and quality of life. AIM: To review the integration, description and critical interpretation of the most recent scientific evidence on the clinical variability of spasticity and associated symptoms, the different pathophysiological mechanisms and their relevance in the diagnostic and therapeutic approach. DEVELOPMENT: A search was conducted in the scientific publications on the different aspects of spasticity grouped into two main categories: cerebral and spinal cord pathologies. The epidemiological, clinical and pathophysiological aspects, clinical and instrumental diagnoses, and the physiotherapeutic, pharmacological and surgical approach to spasticity in each group of pathologies were all reviewed. CONCLUSION: Spasticity is related to structural lesions and maladaptive neuroplastic changes that determine an important variability in its clinical expression. Although its diagnosis presents important limitations, the use of clinical and neurophysiological diagnostic tools aimed at achieving different approaches in cases of neurological pathologies originating in the brain and in the spinal cord could optimise the effectiveness of spasticity therapies.


TITLE: Espasticidad en la patología neurológica. Actualización sobre mecanismos fisiopatológicos, avances en el diagnóstico y tratamiento.Introducción. La espasticidad es un signo clínico frecuente en personas con enfermedades neurológicas que afecta a la movilidad y causa graves complicaciones: dolor, limitación articular, contracturas y úlceras por presión, que conllevan una afectación significativa de la funcionalidad del individuo y de su calidad de vida. Objetivo. Revisar la integración, la descripción y la interpretación crítica de la evidencia científica más reciente sobre la variabilidad clínica de la espasticidad y los síntomas asociados, los distintos mecanismos fisiopatológicos y su relevancia en el abordaje diagnóstico y terapéutico. Desarrollo. Se realizó una búsqueda de las publicaciones científicas sobre los distintos aspectos de la espasticidad agrupados en dos categorías magistrales: patologías cerebral y medular; y se revisaron aspectos epidemiológicos, clínicos y fisiopatológicos, el diagnóstico clínico e instrumental, y el abordaje fisioterapéutico, farmacológico y quirúrgico de la espasticidad en cada grupo de patologías. Conclusión. La espasticidad se relaciona con lesiones estructurales y cambios neuroplásticos maladaptativos que determinan una importante variabilidad en su expresión clínica. Aunque su diagnóstico presenta importantes limitaciones, el uso de herramientas de diagnóstico clínico y neurofisiológico encaminadas al abordaje diferencial en las patologías neurológicas de origen cerebral y medular podría optimizar la eficacia de las terapias de la espasticidad.


Assuntos
Espasticidade Muscular , Doenças do Sistema Nervoso/complicações , Algoritmos , Humanos , Espasticidade Muscular/diagnóstico , Espasticidade Muscular/etiologia , Espasticidade Muscular/fisiopatologia , Espasticidade Muscular/terapia
5.
Poult Sci ; 97(5): 1579-1587, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29462477

RESUMO

Meat from the Greater rhea (Rhea americana) could compete with traditional red meats, diversifying the market of protein products of animal origin. The meat from 32 rheas was used to study quality aspects and this included ultimate pH (pHu), color, water-holding capacity (WHC%), cooking loss (CL%) and tenderness. The muscles sampled were the Gastrocnemius pars externa, Iliofibularis and Obturatorius medialis from both sexes at multiple ages (10, 12, 14, 16 months). Age at slaughter affected WHC%, CL%, and color in raw meat and tenderness in cooked meat. Muscles under study showed differences in terms of pHu, raw meat color, and tenderness of cooked meat. Sex did not have a significant effect on any of the variables studied. According to our results, rhea meat from younger animals, between 10 to 14 months old, was tender and moderately juicy and the visual color was appreciated by the consumers.


Assuntos
Carne/análise , Músculo Esquelético/fisiologia , Reiformes/fisiologia , Fatores Etários , Animais , Feminino , Masculino , Distribuição Aleatória , Fatores Sexuais
6.
Eur J Phys Rehabil Med ; 50(2): 231-42, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24842220

RESUMO

During the last decade, many studies have been carried out to understand the effects of focal vibratory stimuli at various levels of the central nervous system and to study pathophysiological mechanisms of neurological disorders as well as the therapeutic effects of focal vibration in neurorehabilitation. This review aimed to describe the effects of focal vibratory stimuli in neurorehabilitation including the neurological diseases or disorders like stroke, spinal cord injury, multiple sclerosis, Parkinson's' disease and dystonia. In conclusion, focal vibration stimulation is well tolerated, effective and easy to use, and it could be used to reduce spasticity, to promote motor activity and motor learning within a functional activity, even in gait training, independent from etiology of neurological pathology. Further studies are needed in the future well-designed trials with bigger sample size to determine the most effective frequency, amplitude and duration of vibration application in the neurorehabilitation.


Assuntos
Terapia por Exercício/métodos , Terapia por Exercício/enfermagem , Doenças do Sistema Nervoso/reabilitação , Vibração/uso terapêutico , Humanos
9.
Top Spinal Cord Inj Rehabil ; 18(2): 106-12, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23459246

RESUMO

OBJECTIVE: To assess the effect of high-frequency repetitive transcranial magnetic stimulation (rTMS) on lower extremities motor score (LEMS) and gait in patients with motor incomplete spinal cord injury (SCI). METHOD: The prospective longitudinal randomized, double-blind study assessed 17 SCI patients ASIA D. We assessed LEMS, modified Ashworth Scale (MAS), 10-m walking test (10MWT), Walking Index for SCI (WISCI II) scale, step length, cadence, and Timed Up and Go (TUG) test at baseline, after the last of 15 daily sessions of rTMS and 2 weeks later. Patients were randomized to active rTMS or sham stimulation. Three patients from the initial group of 10 randomized to sham stimulation entered the active rTMS group after a 3-week washout period. Therefore a total of 10 patients completed each study condition. Both groups were homogeneous for age, gender, time since injury, etiology, and ASIA scale. Active rTMS consisted of 15 days of daily sessions of 20 trains of 40 pulses at 20 Hz and an intensity of 90% of resting motor threshold. rTMS was applied with a double cone coil to the leg motor area. RESULTS: There was a significant improvement in LEMS in the active group (28.4 at baseline and 33.2 after stimulation; P = .004) but not in the sham group (29.6 at baseline, and 30.9 after stimulation; P = .6). The active group also showed significant improvements in the MAS, 10MWT, cadence, step length, and TUG, and these improvements were maintained 2 weeks later. Following sham stimulation, significant improvement was found only for step length and TUG. No significant changes were observed in the WISCI II scale in either group. CONCLUSION: High-frequency rTMS over the leg motor area can improve LEMS, spasticity, and gait in patients with motor incomplete SCI.

10.
Rev. Esc. Salud Pública ; 13(1): 6-17, jun. 2009. tab
Artigo em Espanhol | BINACIS | ID: bin-125079

RESUMO

Con el objetivo de conocer las principales característicasepidemiológicas de la mortalidad por suicidio en el Uruguay,se realizó un estudio descriptivo. Uruguay se ubicó en elprimer tercio de los países con las tasas de suicidio máselevadas del mundo, en el tercer lugar de América y en elprimero de Sudamérica. Presentó para el año 2000 unatasa del 18.76 por cien mil, ocurriendo un promedio de 1.7suicidios por día, representando la novena causa de muerte.Las tasas más elevadas se presentaron en el sexo masculino;entre divorciados/as y viudos/as y el método más usadofue el disparo por arma de fuego. Para el Departamento deMontevideo, el promedio de AVPP por suicidio fue de 28 y29 años para el sexo femenino y masculino respectivamente,se destaca las mayores tasas en el nivel de instrucciónterciaria, en desocupados y jubilados; y en nivelessocioeconómicos medios o bajos. El suicidio es consideradoun problema de Salud Pública.(AU)


Assuntos
Humanos , Suicídio , Suicídio/estatística & dados numéricos , Mortalidade , Saúde Pública
11.
Rev. salud pública (Córdoba) ; 13(1): 6-17, jun. 2009. tab
Artigo em Espanhol | LILACS | ID: lil-528885

RESUMO

Con el objetivo de conocer las principales característicasepidemiológicas de la mortalidad por suicidio en el Uruguay,se realizó un estudio descriptivo. Uruguay se ubicó en elprimer tercio de los países con las tasas de suicidio máselevadas del mundo, en el tercer lugar de América y en elprimero de Sudamérica. Presentó para el año 2000 unatasa del 18.76 por cien mil, ocurriendo un promedio de 1.7suicidios por día, representando la novena causa de muerte.Las tasas más elevadas se presentaron en el sexo masculino;entre divorciados/as y viudos/as y el método más usadofue el disparo por arma de fuego. Para el Departamento deMontevideo, el promedio de AVPP por suicidio fue de 28 y29 años para el sexo femenino y masculino respectivamente,se destaca las mayores tasas en el nivel de instrucciónterciaria, en desocupados y jubilados; y en nivelessocioeconómicos medios o bajos. El suicidio es consideradoun problema de Salud Pública.


Assuntos
Humanos , Saúde Pública , Suicídio , Suicídio/estatística & dados numéricos , Mortalidade
12.
J Nanosci Nanotechnol ; 4(8): 1056-61, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15656202

RESUMO

A thorough microstructural and magnetic analysis has been performed on as-quenched and annealed (475 and 525 degrees C, 1 hour) melt-spun Cu100-xCox (x = 10 and 15) granular alloys, presenting a giant magnetoresistance (GMR) effect. The annealed samples are inhomogeneous with respect to the Co-particle sizes and interparticles distances and, therefore, these particles present superparamagnetic and ferromagnetic behaviours, which determine the GMR response. The samples x = 15, treated at 525 degrees C during 1 hour, presented the best GMR ratio (approximately 5% at room temperature to be the highest value approaching roughly to the saturation under an applied magnetic field of 15 KOe), with the coexistence of Co-particles with both kinds of magnetic behaviour.


Assuntos
Cobalto/química , Cobre/química , Cristalização/métodos , Temperatura Alta , Magnetismo , Nanotecnologia/métodos , Nanotubos/química , Cobalto/análise , Cobre/análise , Impedância Elétrica , Teste de Materiais , Nanotubos/análise , Tamanho da Partícula
13.
Diagn Cytopathol ; 25(6): 365-75, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11747233

RESUMO

There are many helpful cytological criteria for the diagnosis of liver fine-needle aspiration biopsies (FNABs), but none of them are pathognomonic of primary or metastatic tumors. We analyzed the diagnostic value and reproducibility of 28 cytological parameters in FNABs from 140 hepatic masses, including 29 benign lesions, 49 hepatocellular carcinomas (HCCs), and 62 metastatic tumors, encompassing 48 adenocarcinomas (ACAs). Five different observers evaluated each sample, and the interobserver and intraobserver agreement was studied. Multivariable analysis showed that the criteria more closely associated with malignancy were irregular nuclear contour, three-dimensional cell groups, and atypical naked nuclei. Capillaries separating tumor cells and granular cytoplasm were strongly associated with HCCs, while eccentrically placed nuclei and necrosis were most commonly seen in ACAs and in metastatic tumors. The intraobserver and interobserver agreement was excellent for the final cytological diagnosis, and there was fair to very good interobserver agreement for 22 of the 28 criteria studied. Architectural features were less reproducible than pure cytological criteria. Intraobserver variability was not influenced by the years of experience in the field. A precise and strict definition of terminology rendered a better reproducibility of the cytological criteria.


Assuntos
Neoplasias Hepáticas/patologia , Fígado/patologia , Biópsia por Agulha , Núcleo Celular/patologia , Humanos , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/secundário , Metástase Neoplásica/patologia , Variações Dependentes do Observador , Reprodutibilidade dos Testes
14.
Actas Urol Esp ; 23(6): 477-82, 1999 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-10464955

RESUMO

OBJECTIVES: To establish the reliability of three cystopathologists for cytological diagnosis of primary bladder tumors. METHODS: Pre-operative voided urine specimens of 71 patients with bladder cancer and 55 healthy controls were retrospectively and blindly reviewed by 3 independent cytologists, and their results--positive for bladder cancer, negative or inconclusive--were compared with each other. The estimation of the interobserver agreement was calculated using the weighted kappa-coefficient (k). A multivariative analysis was carried out to identify the factors associated with the disagreement among the three observers. The sensitivity and specificity for each of the participants were calculated in order to clearly identify the origin of the disagreement, in terms of the performance of the diagnostic test in the hands of each observer. A comparison of the overall diagnostic performance was made by plotting sensitivity versus 1-specificity. RESULTS: The weighted k coefficient among observers was 0.46. The multivariative analysis did not identify any variable that could have caused such disagreement. Large differences in sensitivity and specificity were detected between observer number 1 (sens., 0.90, spec., 0.45) and observers number 2 (sens., 0.67, spec., 0.72) and number 3 (sens., 0.71, spec., 0.80), but the overall diagnostic performance (sensitivity vs 1-specificity) was superimposable in the three cases (p = ns). CONCLUSIONS: Simple, reproducible and agreed-on diagnostic criteria should be established to yield reliable results in a group of cytologists. The consideration of individual diagnostic performances can give a false idea of homogeneity between observers. In this field, concordance analysis makes quality control reliable and should be a routine procedure of any pathology department.


Assuntos
Neoplasias da Bexiga Urinária/diagnóstico , Feminino , Histocitoquímica , Humanos , Masculino , Análise Multivariada , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
15.
Eur Urol ; 35(3): 228-32, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10072625

RESUMO

OBJECTIVES: To establish the reliability of three cytopathologists for cytological diagnosis of primary bladder tumors. METHODS: Preoperative voided urine specimens of 71 patients with bladder cancer and 55 noncancer controls were retrospectively and blindly reviewed by 3 independent cytologists, and their results compared. The estimation of the interobserver agreement was calculated using the weighted kappa coefficient. A multivariate analysis was carried out to identify the factors associated with the disagreement between the three observers. The sensitivity and specificity for each of the participants was calculated in order to clearly identify the origin of the disagreement, in terms of the performance of the diagnostic test in the hands of each observer. A comparison of the overall diagnostic performance was made by plotting sensitivity versus 1-specificity. RESULTS: The weighted kappa coefficient among the 3 observers was 0.46. The multivariate analysis did not identify any variable that could have caused such disagreement. Vast differences in sensitivity and specificity were detected between observer 1 (sens. 0.90, spec. 0.45) and observers 2 (sens. 0.67, spec. 0.72) and 3 (sens. 0.71, spec. 0.80), but the overall diagnostic performance (sensitivity vs. 1-specificity) was superimposable in the 3 cases (p = NS). CONCLUSIONS: Simple, reproducible and agreed-on-diagnostic criteria should be established to yield reliable results in a group of cytologists. The consideration of individual diagnostic performances can give a false idea of homogeneity between observers. In this field, concordance analysis makes quality control reliable and should be a routine procedure of any pathology department.


Assuntos
Carcinoma de Células de Transição/patologia , Neoplasias da Bexiga Urinária/patologia , Carcinoma de Células de Transição/epidemiologia , Carcinoma de Células de Transição/urina , Feminino , Humanos , Masculino , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Neoplasias da Bexiga Urinária/epidemiologia , Neoplasias da Bexiga Urinária/urina , Urina/citologia
16.
Panamá; s.n; 1997. 432 p. tab, ilus.
Tese em Espanhol | LILACS | ID: lil-287802

RESUMO

Prepara un manual que incluye toda la información toxicológica concerniente a los plaguicidas de uso agropecuario y veterinario registrados en Panamá. Revisa bibliografía sobre el tema y los expedientes de información archivada y presentada por los fabricantes en el Departamento de Farmacia y Drogas del Ministerio de Salud de la República de Panamá. Presenta los métodos analíticos de un gran número de compuestos. También, enlista los plaguicidas de uso agrícola y veterinario por orden alfabético según principio activo y según nombre del producto


Assuntos
Saúde , Uso de Praguicidas , Praguicidas , Intoxicação/diagnóstico , Intoxicação/epidemiologia
19.
Anat Histol Embryol ; 21(2): 160-74, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1497145

RESUMO

We have designed a method for measuring mechanical forces acting on the area pellucida of the chick embryo between stages 1 to 5 of HAMBURGER and HAMILTON (1951). The coordinates of several points on the outline of the area pellucida were used as input, from which a computer program measured the changes in the position of similar points to produce a table of values which, we argue, reflect mechanical forces in the embryo. The results obtained are shown to be reproducible between embryos. The computer program and the measurements obtained were then used to predict the behaviour of surgical incisions made in the area pellucida, using the tables obtained from direct measurements of embryos and the coordinates of various points on the surface of the operated embryos. This procedure was applied to embryos cultured by the method of NEW (1955) and in-ovo. It was found that in those embryos cultured by EWS technique the computer predictions correspond very closely to shape measurements made directly from embryos. However, the correspondence is less close when applied to embryos in-ovo.


Assuntos
Embrião de Galinha/fisiologia , Zona Pelúcida/fisiologia , Animais , Fenômenos Biomecânicos , Software
20.
Artigo em Espanhol | LILACS | ID: lil-97978

RESUMO

La incidencia de la infección VIH en hemofílicos en Latino América varía de 2-4 a 72.4% en los diferentes países


Assuntos
Humanos , Hemofilia A/imunologia , Infecções por HIV/epidemiologia , Grupos de Risco/epidemiologia
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