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1.
Georgian Med News ; (330): 99-105, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36427851

RESUMO

Coronavirus disease 2019 (Covid-19) active cases continue to demand the development of safe and effective treatments. This is the first clinical trial to evaluate the safety and efficacy of oral thymic peptides. ; We conducted a nonrandomized phase 2 trial with a historic control group to evaluate the safety and efficacy of a daily 250-mg oral dose of thymic peptides in the treatment of hospitalized Covid-19 patients. Comparisons based on standard care from registry data were performed after propensity score matching. The primary outcomes were survival, time to recovery, and number of participants with treatment-related adverse events or side effects by day 20. ; A total of 44 patients were analyzed in this study: 22 in the thymic peptide group and 22 in the standard care group. There were no deaths in the intervention group compared to 24% mortality in standard care by day 20 (log-rank P=0.02). Kaplan-Meier analysis showed a significantly shorter time to recovery by day 20 in the thymic peptide group than in the standard care group (median, 6 days vs. 12 days; hazard ratio for recovery, 2.75 [95% confidence interval, 1.34 to 5.62]; log-rank P=0.002). No side effects or adverse events were reported. ; In patients hospitalized with Covid-19, the use of thymic peptides resulted in no side effects, adverse events, or deaths by day 20. Compared with the registry data, a significantly shorter time to recovery and mortality reduction were measured.


Assuntos
Tratamento Farmacológico da COVID-19 , Peptídeos , Humanos , Honduras , Estimativa de Kaplan-Meier , Peptídeos/efeitos adversos , Modelos de Riscos Proporcionais
2.
Exp Neurol ; 358: 114220, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36064003

RESUMO

Perineuronal nets (PNNs) are a specialized extracellular matrix that have been extensively studied in the brain. Cortical PNNs are implicated in synaptic stabilization, plasticity inhibition, neuroprotection, and ionic buffering. However, the role of spinal PNNs, mainly found around motoneurons, is still unclear. Thus, the goal of this study is to elucidate the role of spinal PNNs on motor function and plasticity in both intact and spinal cord injured mice. We used transgenic mice lacking the cartilage link protein 1 (Crtl1 KO mice), which is implicated in PNN assembly. Crtl1 KO mice showed disorganized PNNs with an altered proportion of their components in both motor cortex and spinal cord. Behavioral and electrophysiological tests revealed motor impairments and hyperexcitability of spinal reflexes in Crtl1 KO compared to WT mice. These functional outcomes were accompanied by an increase in excitatory synapses around spinal motoneurons. Moreover, following spinal lesions of the corticospinal tract, Crtl1 KO mice showed increased contralateral sprouting compared to WT mice. Altogether, the lack of Crtl1 generates aberrant PNNs that alter excitatory synapses and change the physiological properties of motoneurons, overall altering spinal circuits and producing motor impairment. This disorganization generates a permissive scenario for contralateral axons to sprout after injury.


Assuntos
Matriz Extracelular , Córtex Motor , Animais , Matriz Extracelular/metabolismo , Camundongos , Camundongos Transgênicos , Plasticidade Neuronal/fisiologia , Tratos Piramidais , Sinapses
3.
Br J Dermatol ; 186(1): 142-152, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34254291

RESUMO

BACKGROUND: Cutaneous reactions after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines are poorly characterized. OBJECTIVE: To describe and classify cutaneous reactions after SARS-CoV-2 vaccination. METHODS: A nationwide Spanish cross-sectional study was conducted. We included patients with cutaneous reactions within 21 days of any dose of the approved vaccines at the time of the study. After a face-to-face visit with a dermatologist, information on cutaneous reactions was collected via an online professional survey and clinical photographs were sent by email. Investigators searched for consensus on clinical patterns and classification. RESULTS: From 16 February to 15 May 2021, we collected 405 reactions after vaccination with the BNT162b2 (Pfizer-BioNTech; 40·2%), mRNA-1273 (Moderna; 36·3%) and AZD1222 (AstraZeneca; 23·5%) vaccines. Mean patient age was 50·7 years and 80·2% were female. Cutaneous reactions were classified as injection site ('COVID arm', 32·1%), urticaria (14·6%), morbilliform (8·9%), papulovesicular (6·4%), pityriasis rosea-like (4·9%) and purpuric (4%) reactions. Varicella zoster and herpes simplex virus reactivations accounted for 13·8% of reactions. The COVID arm was almost exclusive to women (95·4%). The most reported reactions in each vaccine group were COVID arm (mRNA-1273, Moderna, 61·9%), varicella zoster virus reactivation (BNT162b2, Pfizer-BioNTech, 17·2%) and urticaria (AZD1222, AstraZeneca, 21·1%). Most reactions to the mRNA-1273 (Moderna) vaccine were described in women (90·5%). Eighty reactions (21%) were classified as severe/very severe and 81% required treatment. CONCLUSIONS: Cutaneous reactions after SARS-CoV-2 vaccination are heterogeneous. Most are mild-to-moderate and self-limiting, although severe/very severe reactions are reported. Knowledge of these reactions during mass vaccination may help healthcare professionals and reassure patients.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Vacina de mRNA-1273 contra 2019-nCoV , Vacina BNT162 , ChAdOx1 nCoV-19 , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , SARS-CoV-2 , Vacinação/efeitos adversos
4.
Cell Tissue Res ; 384(1): 167-177, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33471198

RESUMO

Injuries to the peripheral nerves represent a frequent cause of permanent disability in adults. The repair of large nerve lesions involves the use of autografts, but they have several inherent limitations. Overcoming these limitations, the use of decellularized nerve matrix has emerged as a promising treatment in tissue regenerative medicine. Here, we generate longer human decellularized nerve segments with a novel decellularization method, using nonionic, zwitterionic, and enzymatic incubations. Efficiency of decellularization was measured by DNA quantification and cell remnant analysis (myelin, S100, neurofilament). The evaluation of the extracellular matrix (collagen, laminin, and glycosaminoglycans) preservation was carried out by enzyme-linked immunosorbent assay (ELISA) or biochemical methods, along with histological and immunofluorescence analysis. Moreover, biomechanical properties and cytocompatibility were tested. Results showed that the decellularized nerves generated with this protocol have a concentration of DNA below the threshold of 50 ng/mg of dry tissue. Furthermore, myelin, S100, and MHCII proteins were absent, although some neurofilament remnants could be observed. Moreover, extracellular matrix proteins were well maintained, as well as the biomechanical properties, and the decellularized nerve matrix did not generate cytotoxicity. These results show that our method is effective for the generation of decellularized human nerve grafts. The generation of longer decellularized nerve segments would allow the understanding of the regenerative neurobiology after nerve injuries in both clinical assays and bigger animal models. Effective decellularization of human nerve matrix for regenerative medicine with a novel protocol. Combination of zwitterionic, non-ionic detergents, hyperosmotic solution and nuclease enzyme treatment remove cell remnants, maintain collagen, laminin and biomechanics without generating cytotoxic leachables.


Assuntos
Matriz Extracelular/metabolismo , Tecido Nervoso/metabolismo , Medicina Regenerativa/métodos , Humanos
5.
Actas dermo-sifiliogr. (Ed. impr.) ; 110(7): 533-545, sept. 2019. tab
Artigo em Espanhol | IBECS | ID: ibc-185525

RESUMO

Las últimas evidencias científicas y la incorporación de nuevos fármacos al arsenal terapéutico de la rosácea hacen necesario revisar y actualizar los criterios y estrategias de tratamiento. Con este fin, un grupo de 15 dermatólogos expertos en esta enfermedad aportaron y discutieron acerca de las diferentes terapias y los criterios de respuesta y cambio de tratamiento. Partiendo de la revisión crítica de la bibliografía y de la exposición de los hábitos de los dermatólogos españoles en su práctica clínica, se formularon distintas propuestas que fueron debatidas teniendo en consideración tanto la experiencia profesional como las preferencias de los pacientes o los criterios de equidad. Una vez validadas las propuestas, se formularon las recomendaciones finales que, junto con la evidencia aportada por las principales guías y estudios internacionales, dieron lugar al presente documento. El objetivo de este consenso es ofrecer al dermatólogo un enfoque práctico para abordar la rosácea


Recent scientific evidence and the incorporation of new drugs into the therapeutic arsenal against rosacea have made it necessary to review and update treatment criteria and strategies. To this end, a panel of 15 dermatologists, all experts in rosacea, was formed to share experiences and discuss treatment options, response criteria, and changes to treatment. Based on a critical review of the literature and a discussion of the routine practices of Spanish dermatologists, the panel proposed and debated different options, with consideration of the experience of professionals and the preferences of patients or equality criteria. Following validation of the proposals, the final recommendations were formulated and, together with the evidence from the main international guidelines and studies, used to produce this consensus document. The goal of this consensus document is to provide dermatologists with practical recommendations for the management of rosacea


Assuntos
Humanos , Consenso , Algoritmos , Rosácea/terapia , Rosácea/epidemiologia , Inquéritos e Questionários , Qualidade de Vida , Eritema/terapia , Telangiectasia/terapia , Administração Tópica , Técnica Delfos
6.
Actas Dermosifiliogr (Engl Ed) ; 110(7): 533-545, 2019 Sep.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30837074

RESUMO

Recent scientific evidence and the incorporation of new drugs into the therapeutic arsenal against rosacea have made it necessary to review and update treatment criteria and strategies. To this end, a panel of 15 dermatologists, all experts in rosacea, was formed to share experiences and discuss treatment options, response criteria, and changes to treatment. Based on a critical review of the literature and a discussion of the routine practices of Spanish dermatologists, the panel proposed and debated different options, with consideration of the experience of professionals and the preferences of patients or equality criteria. Following validation of the proposals, the final recommendations were formulated and, together with the evidence from the main international guidelines and studies, used to produce this consensus document. The goal of this consensus document is to provide dermatologists with practical recommendations for the management of rosacea.


Assuntos
Algoritmos , Consenso , Rosácea/terapia , Antibacterianos/uso terapêutico , Tartarato de Brimonidina/uso terapêutico , Técnica Delfos , Doxiciclina/uso terapêutico , Humanos , Terapia a Laser , Metronidazol/uso terapêutico , Guias de Prática Clínica como Assunto , Qualidade de Vida , Rosácea/classificação , Rosácea/tratamento farmacológico
7.
Actas dermo-sifiliogr. (Ed. impr.) ; 109(9): 771-776, nov. 2018. graf
Artigo em Espanhol | IBECS | ID: ibc-175739

RESUMO

Antecedentes y objetivo: Los ensayos pivotales de omalizumab en urticaria crónica espontánea (UCE) tienen un periodo de tratamiento de entre 12 y 24 semanas. Sin embargo, muchos pacientes en práctica clínica requieren periodos de tratamiento más prolongados. Por ello el objetivo es presentar un algoritmo de manejo del fármaco. Materiales y métodos: El documento de consenso que detallamos nace de la puesta en común, aceptación, revisión y confrontación de la literatura reciente del grupo de trabajo de UCE "Xarxa d'Urticària Catalana i Balear" (XUrCB). Resultados: Se inicia el tratamiento a dosis autorizada y se ajusta la dosis en intervalos trimestrales en función del Urticaria Activity Score de los últimos 7 días (UAS7) y/o el Urticarial Control Test (UCT). Conclusiones: El algoritmo propuesto pretende servir de guía respecto a cómo ajustar dosis, cómo y cuándo parar el fármaco y el modo de reintroducirlo en casos de recaída


Background and objective: Pivotal trials with omalizumab for treatment of chronic spontaneous urticaria (CSU) are generally run over 12 to 24weeks. However, in clinical practice, many patients need longer treatment. In this article, we present an algorithm for treatment with omalizumab. Material and methods: The consensus document we present is the result of a series of meetings by the CSU working group of "Xarxa d'Urticària Catalana i Balear" (XUrCB) at which data from the recent literature were presented, discussed, compared, and agreed upon. Results: Treatment with omalizumab should be initiated at the authorized dose, and is adjusted at 3-monthly intervals according to the Urticaria Activity Score Over 7 days, the Urticaria Control Test, or both. Conclusions: The algorithm proposed is designed to provide guidance on how to adjust omalizumab doses, how and when to discontinue the drug, and how to reintroduce it in cases of relapse


Assuntos
Humanos , Urticária/tratamento farmacológico , Omalizumab/administração & dosagem , Algoritmos , Consenso , Dosagem/métodos , Antagonistas dos Receptores Histamínicos H1/administração & dosagem , Relação Dose-Resposta a Droga
8.
Actas Dermosifiliogr (Engl Ed) ; 109(9): 771-776, 2018 Nov.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30107875

RESUMO

BACKGROUND AND OBJECTIVE: Pivotal trials with omalizumab for treatment of chronic spontaneous urticaria (CSU) are generally run over 12 to 24weeks. However, in clinical practice, many patients need longer treatment. In this article, we present an algorithm for treatment with omalizumab. MATERIAL AND METHODS: The consensus document we present is the result of a series of meetings by the CSU working group of "Xarxa d'Urticària Catalana i Balear" (XUrCB) at which data from the recent literature were presented, discussed, compared, and agreed upon. RESULTS: Treatment with omalizumab should be initiated at the authorized dose, and is adjusted at 3-monthly intervals according to the Urticaria Activity Score Over 7days, the Urticaria Control Test, or both. CONCLUSIONS: The algorithm proposed is designed to provide guidance on how to adjust omalizumab doses, how and when to discontinue the drug, and how to reintroduce it in cases of relapse.


Assuntos
Algoritmos , Antialérgicos/uso terapêutico , Omalizumab/uso terapêutico , Urticária/tratamento farmacológico , Antialérgicos/administração & dosagem , Doença Crônica , Humanos , Omalizumab/administração & dosagem
9.
J Forensic Leg Med ; 55: 1-7, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29433009

RESUMO

National and international reports regarding the paternity testing activity scarcely include information from Mexico and other Latin American countries. Therefore, we report different results from the analysis of 3005 paternity cases analyzed during a period of five years in a Mexican paternity testing laboratory. Motherless tests were the most frequent (77.27%), followed by trio cases (20.70%); the remaining 2.04% included different cases of kinship reconstruction. The paternity exclusion rate was 29.58%, higher but into the range reported by the American Association of Blood Banks (average 24.12%). We detected 65 mutations, most of them involving one-step (93.8% and the remaining were two-step mutations (6.2%) thus, we were able to estimate the paternal mutation rate for 17 different STR loci: 0.0018 (95% CI 0.0005-0.0047). Five triallelic patterns and 12 suspected null alleles were detected during this period; however, re-amplification of these samples with a different Human Identification (HID) kit confirmed the homozygous genotypes, which suggests that most of these exclusions actually are one-step mutations. HID kits with ≥20 STRs detected more exclusions, diminishing the rate of inconclusive results with isolated exclusions (<3 loci), and leading to higher paternity indexes (PI). However, the Powerplex 21 kit (20 STRs) and Powerplex Fusion kit (22 STRs) offered similar PI (p = 0.379) and average number of exclusions (PE) (p = 0.339) when a daughter was involved in motherless tests. In brief, besides to report forensic parameters from paternity tests in Mexico, results describe improvements to solve motherless paternity tests using HID kits with ≥20 STRs instead of one including 15 STRs.


Assuntos
Paternidade , Cromossomos Humanos Y , Genótipo , Homozigoto , Humanos , Masculino , México , Repetições de Microssatélites , Mutação , Reação em Cadeia da Polimerase
11.
J Neural Eng ; 14(4): 046015, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28474599

RESUMO

OBJECTIVE: The study of electroencephalographic (EEG) bursts in preterm infants provides valuable information about maturation or prognostication after perinatal asphyxia. Over the last two decades, a number of works proposed algorithms to automatically detect EEG bursts in preterm infants, but they were designed for populations under 35 weeks of post menstrual age (PMA). However, as the brain activity evolves rapidly during postnatal life, these solutions might be under-performing with increasing PMA. In this work we focused on preterm infants reaching term ages (PMA ⩾36 weeks) using multi-feature classification on a single EEG channel. APPROACH: Five EEG burst detectors relying on different machine learning approaches were compared: logistic regression (LR), linear discriminant analysis (LDA), k-nearest neighbors (kNN), support vector machines (SVM) and thresholding (Th). Classifiers were trained by visually labeled EEG recordings from 14 very preterm infants (born after 28 weeks of gestation) with 36-41 weeks PMA. MAIN RESULTS: The most performing classifiers reached about 95% accuracy (kNN, SVM and LR) whereas Th obtained 84%. Compared to human-automatic agreements, LR provided the highest scores (Cohen's kappa = 0.71) using only three EEG features. Applying this classifier in an unlabeled database of 21 infants ⩾36 weeks PMA, we found that long EEG bursts and short inter-burst periods are characteristic of infants with the highest PMA and weights. SIGNIFICANCE: In view of these results, LR-based burst detection could be a suitable tool to study maturation in monitoring or portable devices using a single EEG channel.


Assuntos
Encéfalo/fisiologia , Eletroencefalografia/classificação , Eletroencefalografia/métodos , Recém-Nascido Prematuro/fisiologia , Encéfalo/crescimento & desenvolvimento , Análise Discriminante , Humanos , Recém-Nascido , Recém-Nascido Prematuro/crescimento & desenvolvimento , Máquina de Vetores de Suporte/classificação
12.
J Neural Eng ; 14(4): 046003, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28382924

RESUMO

OBJECTIVE: As artificial prostheses become more refined, they are most often used as a therapeutic option for hand amputation. By contrast to extra- or intraneural interfaces, regenerative nerve electrodes are designed to enable electrical interfaces with regrowing axonal bundles of injured nerves, aiming to achieve high selectivity for recording and stimulation. However, most of the developed designs pose an obstacle to the regrowth mechanisms due to low transparency and cause impairment to the nerve regeneration. APPROACH: Here we present the double-aisle electrode, a new type of highly transparent, non-obstructive regenerative electrode. Using a double-side thin-film polyimide planar multi-contact electrode, two nerve fascicles can regenerate without physical impairment through two electrically isolated aisles. MAIN RESULTS: We show that this electrode can be used to selectively record and stimulate fascicles, acutely as well as chronically, and allow regeneration in nerve gaps of several millimeters without impairment. SIGNIFICANCE: This multi-aisle regenerative electrode may be suitable for neuroprosthetic applications, such as prostheses, for the restoration of hand function after amputation or severe nerve injuries.


Assuntos
Eletrodos Implantados , Miniaturização/métodos , Regeneração Nervosa/fisiologia , Nervos Periféricos/fisiologia , Potenciais de Ação/fisiologia , Animais , Estimulação Elétrica/métodos , Feminino , Microeletrodos , Ratos , Ratos Sprague-Dawley
13.
Biomaterials ; 122: 114-129, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28110171

RESUMO

Stimulation of peripheral nerves has transiently restored lost sensation and has the potential to alleviate motor deficits. However, incomplete characterization of the long-term usability and bio-integration of intra-neural implants has restricted their use for clinical applications. Here, we conducted a longitudinal assessment of the selectivity, stability, functionality, and biocompatibility of polyimide-based intra-neural implants that were inserted in the sciatic nerve of twenty-three healthy adult rats for up to six months. We found that the stimulation threshold and impedance of the electrodes increased moderately during the first four weeks after implantation, and then remained stable over the following five months. The time course of these adaptations correlated with the progressive development of a fibrotic capsule around the implants. The selectivity of the electrodes enabled the preferential recruitment of extensor and flexor muscles of the ankle. Despite the foreign body reaction, this selectivity remained stable over time. These functional properties supported the development of control algorithms that modulated the forces produced by ankle extensor and flexor muscles with high precision. The comprehensive characterization of the implant encapsulation revealed hyper-cellularity, increased microvascular density, Wallerian degeneration, and infiltration of macrophages within the endoneurial space early after implantation. Over time, the amount of macrophages markedly decreased, and a layer of multinucleated giant cells surrounded by a capsule of fibrotic tissue developed around the implant, causing an enlargement of the diameter of the nerve. However, the density of nerve fibers above and below the inserted implant remained unaffected. Upon removal of the implant, we did not detect alteration of skilled leg movements and only observed mild tissue reaction. Our study characterized the interplay between the development of foreign body responses and changes in the electrical properties of actively used intra-neural electrodes, highlighting functional stability of polyimide-based implants over more than six months. These results are essential for refining and validating these implants and open a realistic pathway for long-term clinical applications in humans.


Assuntos
Estimulação Elétrica/instrumentação , Neuroestimuladores Implantáveis , Microeletrodos , Resinas Sintéticas/química , Nervo Isquiático/fisiologia , Animais , Materiais Biocompatíveis/química , Desenho de Equipamento , Análise de Falha de Equipamento , Feminino , Estudos Longitudinais , Ratos , Ratos Endogâmicos Lew , Nervo Isquiático/citologia , Resultado do Tratamento
14.
Int J Legal Med ; 130(6): 1489-1491, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27048213

RESUMO

We analyzed 238 unrelated Mestizo (admixed) individuals from the West region of Mexico with the PowerPlex® Fusion System (Promega Corp.). Allele frequencies and forensic parameters were estimated for the 23 STRs included in this kit. Hardy-Weinberg equilibrium by locus and non-association between pair of loci were demonstrated by exact tests in this population. The combined PE and PD offered by this HID kit were ≥0.9999999986, representing a substantial improvement with respect to those previously offered by 15 STR systems. Interpopulation comparison by AMOVA tests demonstrated low but significant differences among Mexican Mestizos from West, Center, and Northeast regions (Fst = 0.01558; p = 0.0000), similar to the observed among three main ethnic groups from USA (Fst = 0.02048; p = 0.0000). This finding is consistent with the contrary clines of European and Amerindian ancestries described throughout the Mexican territory for Mestizos, the largest population (~90 %) in this country.


Assuntos
Etnicidade/genética , Genética Populacional , Repetições de Microssatélites , Impressões Digitais de DNA , Frequência do Gene , Humanos , México
15.
Neurogastroenterol Motil ; 28(1): 91-100, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26530852

RESUMO

BACKGROUND: Previous studies have found that TRPV1 and TRPA1 receptor agonists improve swallow response in patients with oropharyngeal dysphagia (OD), but little is known about the expression of these receptors in the human oropharynx. The aim of this study was to assess the expression and localization of TRPV1 and TRPA1 in human samples from the oropharynx of healthy patients, to provide the basis for new pharmacological treatments for OD. METHODS: Samples from oropharyngeal regions innervated by cranial nerves V, IX, and X (tongue, pharynx, and epiglottis) were obtained during ENT surgery and processed either for mRNA (21 patients) or for immunohistochemical assays (seven patients). The expression analysis was performed with RT-qPCR using ACTBh as reference gene. Hemotoxylin and eosin staining was used to study the histology; the immunohistochemical assay used (i) neuron-specific enolase to detect nerve fibers or (ii) fluorescent probes to locate TRPV1 and TRPA1. RESULTS: TRPV1 was expressed in the three studied regions, with higher levels in CN V region (tongue) than in CN X region (epiglottis; p < 0.05), and was localized at epithelial cells and nociceptive fibers in all studied regions. TRPA1 was also expressed in all studied regions, but was always localized below the basal lamina. No immunoreactivity for TRPA1 was found on epithelial cells. CONCLUSIONS & INFERENCES: TRPV1 and TRPA1 are widely expressed in the human oropharynx with two distinct patterns. Our study further confirms that TRPV1/A1 receptors are promising therapeutic targets to develop active treatments for OD patients.


Assuntos
Canais de Cálcio/genética , Epiglote/metabolismo , Laringe/metabolismo , Proteínas do Tecido Nervoso/genética , Orofaringe/metabolismo , RNA Mensageiro/metabolismo , Canais de Cátion TRPV/genética , Língua/metabolismo , Canais de Potencial de Receptor Transitório/genética , Adulto , Idoso , Membrana Basal , Canais de Cálcio/metabolismo , Transtornos de Deglutição/genética , Transtornos de Deglutição/metabolismo , Células Epiteliais/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Fibras Nervosas/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Nociceptores/metabolismo , Faringe/metabolismo , Canal de Cátion TRPA1 , Canais de Cátion TRPV/metabolismo , Canais de Potencial de Receptor Transitório/metabolismo
17.
Med Eng Phys ; 37(3): 315-20, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25659233

RESUMO

Electroencephalography (EEG) from preterm infant monitoring systems is usually contaminated by several sources of noise that have to be removed in order to correctly interpret signals and perform automated analysis reliably. Band-pass and adaptive filters (AF) continue to be systematically applied, but their efficacy may be decreased facing preterm EEG patterns such as the tracé alternant and slow delta-waves. In this paper, we propose the combination of EEG decomposition with AF to improve the overall denoising process. Using artificially contaminated signals from real EEGs, we compared the quality of filtered signals applying different decomposition techniques: the discrete wavelet transform, the empirical mode decomposition (EMD) and a recent improved version, the complete ensemble EMD with adaptive noise. Simulations demonstrate that introducing EMD-based techniques prior to AF can reduce up to 30% the root mean squared errors in denoised EEGs.


Assuntos
Eletroencefalografia , Processamento de Sinais Assistido por Computador , Razão Sinal-Ruído , Análise de Ondaletas
18.
J Neural Eng ; 12(1): 016016, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25605565

RESUMO

OBJECTIVE: In this study we present the development and testing in a rat model of the self-opening neural interface (SELINE), a novel flexible peripheral neural interface. APPROACH: This polyimide-based electrode has a three-dimensional structure that provides an anchorage system to the nerve and confers stability after implant. This geometry has been achieved by means of the plastic deformation of polyimide. Mechanical and electrochemical characterizations have been performed to prove the integrity of the electrode with very good results. Functionality of SELINEs for fascicular stimulation has been tested during in vivo acute experiments in the rat. Chronic implants were made to test the biocompatibility of the device. MAIN RESULTS: Results showed that SELINEs significantly improve mechanical anchorage to the nerve. Stimulation stability is considerably enhanced compared to common planar transversal electrodes and stimulation selectivity is increased for some motor fascicles. Chronic experimental results showed that SELINEs neither produce changes in the fascicular organization of sciatic nerves nor signs of nerve degeneration. SIGNIFICANCE: The presented three-dimensional electrode provides an effective anchorage system to the nervous tissue that can improve the stability of the implant for acute and chronic studies.


Assuntos
Potenciais de Ação/fisiologia , Estimulação Elétrica/instrumentação , Eletrodos Implantados , Ouro/química , Resinas Sintéticas/química , Nervo Isquiático/fisiologia , Animais , Módulo de Elasticidade , Impedância Elétrica , Teste de Materiais , Monitorização Neurofisiológica/instrumentação , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estresse Mecânico , Resistência à Tração
19.
Microsurgery ; 35(4): 300-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25471200

RESUMO

Biosynthetic guides can be an alternative to nerve grafts for reconstructing severely injured peripheral nerves. The aim of this study was to evaluate the regenerative capability of chitosan tubes to bridge critical nerve gaps (15 mm long) in the rat sciatic nerve compared with silicone (SIL) tubes and nerve autografts (AGs). A total of 28 Wistar Hannover rats were randomly distributed into four groups (n = 7 each), in which the nerve was repaired by SIL tube, chitosan guides of low (∼2%, DAI) and medium (∼5%, DAII) degree of acetylation, and AG. Electrophysiological and algesimetry tests were performed serially along 4 months follow-up, and histomorphometric analysis was performed at the end of the study. Both groups with chitosan tubes showed similar degree of functional recovery, and similar number of myelinated nerve fibers at mid tube after 4 months of implantation. The results with chitosan tubes were significantly better compared to SIL tubes (P < 0.01), but lower than with AG (P < 0.01). In contrast to AG, in which all the rats had effective regeneration and target reinnervation, chitosan tubes from DAI and DAII achieved 43 and 57% success, respectively, whereas regeneration failed in all the animals repaired with SIL tubes. This study suggests that chitosan guides are promising conduits to construct artificial nerve grafts.


Assuntos
Materiais Biocompatíveis/uso terapêutico , Quitosana/uso terapêutico , Regeneração Tecidual Guiada/métodos , Regeneração Nervosa , Traumatismos dos Nervos Periféricos/cirurgia , Nervo Isquiático/lesões , Tecidos Suporte , Animais , Feminino , Distribuição Aleatória , Ratos , Ratos Wistar , Recuperação de Função Fisiológica , Nervo Isquiático/fisiologia , Nervo Isquiático/cirurgia , Nervo Isquiático/transplante , Transplante Autólogo , Resultado do Tratamento
20.
Acta Neurol Scand ; 131(5): 282-9, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25313013

RESUMO

OBJECTIVES: Thermal quantitative sensory testing (QST) is a non-invasive procedure helpful in the assessment of the function of small Aδ and C nerve sensory fibres. Oxaliplatin (OXA) is an effective chemotherapeutic agent, but is frequently associated with neurotoxic dose-limiting side effects. This controlled clinical trial evaluated the reliability and accuracy of thermal QST for assessing the OXA-induced acute neuropathic syndrome, whose clinical hallmark is cold-triggered painful paraesthesia. MATERIALS & METHODS: A testing protocol with the Thermal Sensory Analyzer (Medoc) was carried out in 20 colorectal cancer patients during the initial four cycles of OXA-based chemotherapy and in 20 age- and sex-matched healthy volunteers. Testing was carried out on the hands and included the determination of thermal detection and pain thresholds and the intensity of pain evoked by cold stimuli. Calculations were made of: coefficients of test-retest and inter-rater reliability, indices of responsiveness and parameters that quantify diagnostic accuracy. RESULTS: Thermal thresholds showed moderate to good reliability (ρ ≥ 0.383), but were not consistently responsive to the effects of chemotherapy (cold pain thresholds decreased in both groups, although almost twice in patients compared to healthy volunteers). Conversely, the intensity of pain evoked by suprathreshold cold stimuli was reliable (ρ ≥ 0.822), responsive (detected changes over time) and discriminated between patients and healthy volunteers (area under the ROC curve = 0.700). CONCLUSIONS: The procedure was reliable and accurate to evaluate cold hyperalgesia resulting from OXA administration. The data provided may be used to define efficacy endpoints for future clinical trials of therapies for OXA-induced neuropathies and calculate appropriate sample sizes.


Assuntos
Antineoplásicos/efeitos adversos , Hiperalgesia/induzido quimicamente , Hiperalgesia/diagnóstico , Síndromes Neurotóxicas/diagnóstico , Compostos Organoplatínicos/efeitos adversos , Idoso , Temperatura Baixa , Neoplasias Colorretais/tratamento farmacológico , Feminino , Mãos , Humanos , Masculino , Oxaliplatina , Dor/induzido quimicamente , Curva ROC , Reprodutibilidade dos Testes , Limiar Sensorial
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