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1.
Adv Exp Med Biol ; 1438: 149-152, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37845453

RESUMO

Long periods of bed rest for elderly population, due to a femur fracture event, can cause a deterioration in the muscular capacity. Therefore, monitoring of the muscle oxidative capacity in this fragile population is necessary to define the muscular oxidative metabolism state before and after a rehabilitation period. The time-domain near-infrared spectroscopy (TD-NIRS) technique enables the absolute values to be calculated for hemodynamic parameters such as oxy- (O2Hb), deoxy- (HHb), total- (tHb) haemoglobin, and tissue oxygen saturation (SO2) of the muscular tissue. In this work, we have characterized vastus lateralis muscle hemodynamics during a baseline period at two different time points: after the surgery (PRE) and after 15 days of rehabilitation (POST). The mean values for the absolute values of the hemodynamic parameters were: O2Hb_PRE = 49.1 ± 14.1 µM; O2Hb_POST = 47.1 ± 13.4 µM; HHb_PRE = 28.3 ± 10.3 µM; HHb_POST = 26.7 ± 9.9 µM; tHb_PRE = 77.3 ± 23.6 µM; tHb_POST = 73.8 ± 21.4 µM; SO2_PRE = 63.9 ± 4.0% and SO2_POST = 64.9 ± 5.6%. The hemodynamic parameters did not show significant differences at both group and single subject level. These results suggest that for this kind of population, the baseline of the hemodynamic parameters is not the best one to consider to assess the rehabilitation progresses in terms of muscular oxidative metabolism.


Assuntos
Hemoglobinas , Oxigênio , Idoso , Humanos , Oxigênio/metabolismo , Hemoglobinas/metabolismo , Hemodinâmica , Músculo Quadríceps/metabolismo , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Músculo Esquelético/metabolismo , Consumo de Oxigênio/fisiologia
2.
Artigo em Inglês | MEDLINE | ID: mdl-37506005

RESUMO

Software programming is an acquired evolutionary skill originating from consolidated cognitive functions (i.e., attentive, logical, coordination, mathematic calculation, and language comprehension), but the underlying neurophysiological processes are still not completely known. In the present study, we investigated and compared the brain activities supporting realistic programming, text and code reading tasks, analyzing Electroencephalographic (EEG) signals acquired from 11 experienced programmers. Multichannel spectral analysis and a phase-based effective connectivity study were carried out. Our results highlighted that both realistic programming and reading tasks are supported by modulations of the Theta fronto-parietal network, in which parietal areas behave as sources of information, while frontal areas behave as receivers. Nevertheless, during realistic programming, both an increase in Theta power and changes in network topology emerged, suggesting a task-related adaptation of the supporting network system. This reorganization mainly regarded the parietal area, which assumes a prominent role, increasing its hub functioning and its connectivity in the network in terms of centrality and degree.


Assuntos
Encéfalo , Eletroencefalografia , Humanos , Encéfalo/fisiologia , Eletroencefalografia/métodos , Cognição , Atenção/fisiologia , Software , Mapeamento Encefálico/métodos
6.
Sci Rep ; 11(1): 13567, 2021 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-34193904

RESUMO

In this paper, we used time-domain functional near infrared spectroscopy (TD-fNIRS) to evaluate the haemodynamic response function (HRF) in the occipital cortex following visual stimulation in glaucomatous eyes as compared to healthy eyes. A total of 98 subjects were enrolled in the study and clinically classified as healthy subjects, glaucoma patients (primary open-angle glaucoma) and mixed subjects (i.e. with a different classification for the two eyes). After quality check data were used from HRF of 73 healthy and 62 glaucomatous eyes. The amplitudes of the oxygenated and deoxygenated haemoglobin concentrations, together with their latencies with respect to the stimulus onset, were estimated by fitting their time course with a canonical HRF. Statistical analysis showed that the amplitudes of both haemodynamic parameters show a significant association with the pathology and a significant discriminating ability, while no significant result was found for latencies. Overall, our findings together with the ease of use and noninvasiveness of TD-NIRS, make this technique a promising candidate as a supporting tool for a better evaluation of the glaucoma pathology.


Assuntos
Glaucoma de Ângulo Aberto , Hemodinâmica , Hemoglobinas/metabolismo , Estimulação Luminosa , Adulto , Feminino , Glaucoma de Ângulo Aberto/metabolismo , Glaucoma de Ângulo Aberto/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Espectrofotometria Infravermelho
7.
Acta Ortop Mex ; 34(1): 31-37, 2020.
Artigo em Espanhol | MEDLINE | ID: mdl-33230997

RESUMO

INTRODUCTION: Currently there is no universally accepted standard of reference for the diagnosis of carpal tunnel syndrome so it is considered a «latent class¼ pathology, that is, it lacks any diagnostic tests that absolutely certain the presence of disease. METHODS: Prospective, observational and analytical study evaluating the three diagnostic methods used for carpal tunnel syndrome (clinical examination, ultrasound and electromyography). Normality values were set for each diagnostic method. RESULTS: 50 people (14 men and 36 women) were evaluated. The clinical examination showed a positive and significant correlation with the diameter of the affected median nerve (ecography) (R = 0.694, p = 0.032). The values of the under the curve area (UCA) for median nerve conduction speed (MNCS), cubital nerve conduction speed (CNCS), and distal latency (DL) by electromyography were 0.60, 0.519 and less than 0.50 respectively. This states that the diagnostic value of electromyography characteristics is bad. CONCLUSION: Our work establishes clinical examination as a good quality tool being the most sensitive method for diagnosing carpal tunnel syndrome. If there was a need for diagnostic confirmation, the ultrasound proved to be a highly satisfactory study generating less stress, pain and invasion to the patient, decreasing health expenditure and speeding up the process.


INTRODUCCIÓN: Actualmente, no existe un estándar de referencia aceptado universalmente para el diagnóstico del síndrome de túnel carpiano, por lo que se le considera una patología de «clase latente¼, es decir, que carece de alguna prueba diagnóstica que dé certeza absoluta de la presencia de la enfermedad. MÉTODOS: Estudio prospectivo, observacional y analítico en el cual se evaluaron los tres métodos diagnósticos utilizados para el síndrome de túnel carpiano (examen clínico, ecografía y electromiografía). En él, se establecieron valores de normalidad para cada método diagnóstico. RESULTADOS: Se evaluó un total de 50 personas (14 hombres y 36 mujeres). El examen clínico presentó correlación positiva y significativa con el diámetro del nervio mediano afectado (ecografía) (R = 0.694 y p = 0.032). Los valores del área bajo la curva (AUC, por sus siglas en inglés) para la velocidad de conducción del nervio mediano (VCNM), velocidad de conducción de nervio cubital (VCNC) y latencia distal motora (LDM) por electromiografía fueron de 0.60, 0.519 y. CONCLUSIÓN: < 0.50, respectivamente, lo cual determinó que el valor diagnóstico de las características por electromiografía es malo. Nuestro trabajo establece al examen clínico como una herramienta de buena calidad, siendo el método más sensible para el diagnóstico de síndrome de túnel carpiano. Si existiera la necesidad de realizar una confirmación diagnóstica, la ecografía mostró ser un estudio altamente satisfactorio, el cual genera menos estrés, dolor e invasión al paciente, disminuyendo, a su vez, el gasto de salud y agilizando el proceso.


Assuntos
Síndrome do Túnel Carpal , Síndrome do Túnel Carpal/diagnóstico por imagem , Feminino , Humanos , Masculino , Nervo Mediano/diagnóstico por imagem , Condução Nervosa , Estudos Prospectivos , Sensibilidade e Especificidade , Ultrassonografia
8.
Acta ortop. mex ; 34(1): 31-37, ene.-feb. 2020. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1345082

RESUMO

Resumen: Introducción: Actualmente, no existe un estándar de referencia aceptado universalmente para el diagnóstico del síndrome de túnel carpiano, por lo que se le considera una patología de «clase latente¼, es decir, que carece de alguna prueba diagnóstica que dé certeza absoluta de la presencia de la enfermedad. Métodos: Estudio prospectivo, observacional y analítico en el cual se evaluaron los tres métodos diagnósticos utilizados para el síndrome de túnel carpiano (examen clínico, ecografía y electromiografía). En él, se establecieron valores de normalidad para cada método diagnóstico. Resultados: Se evaluó un total de 50 personas (14 hombres y 36 mujeres). El examen clínico presentó correlación positiva y significativa con el diámetro del nervio mediano afectado (ecografía) (R = 0.694 y p = 0.032). Los valores del área bajo la curva (AUC, por sus siglas en inglés) para la velocidad de conducción del nervio mediano (VCNM), velocidad de conducción de nervio cubital (VCNC) y latencia distal motora (LDM) por electromiografía fueron de 0.60, 0.519 y < 0.50, respectivamente, lo cual determinó que el valor diagnóstico de las características por electromiografía es malo. Conclusión: Nuestro trabajo establece al examen clínico como una herramienta de buena calidad, siendo el método más sensible para el diagnóstico de síndrome de túnel carpiano. Si existiera la necesidad de realizar una confirmación diagnóstica, la ecografía mostró ser un estudio altamente satisfactorio, el cual genera menos estrés, dolor e invasión al paciente, disminuyendo, a su vez, el gasto de salud y agilizando el proceso.


Abstract: Introduction: Currently there is no universally accepted standard of reference for the diagnosis of carpal tunnel syndrome so it is considered a «latent class¼ pathology, that is, it lacks any diagnostic tests that absolutely certain the presence of disease. Methods: Prospective, observational and analytical study evaluating the three diagnostic methods used for carpal tunnel syndrome (clinical examination, ultrasound and electromyography). Normality values were set for each diagnostic method. Results: 50 people (14 men and 36 women) were evaluated. The clinical examination showed a positive and significant correlation with the diameter of the affected median nerve (ecography) (R = 0.694, p = 0.032). The values of the under the curve area (UCA) for median nerve conduction speed (MNCS), cubital nerve conduction speed (CNCS), and distal latency (DL) by electromyography were 0.60, 0.519 and less than 0.50 respectively. This states that the diagnostic value of electromyography characteristics is bad. Conclusion: Our work establishes clinical examination as a good quality tool being the most sensitive method for diagnosing carpal tunnel syndrome. If there was a need for diagnostic confirmation, the ultrasound proved to be a highly satisfactory study generating less stress, pain and invasion to the patient, decreasing health expenditure and speeding up the process.


Assuntos
Humanos , Masculino , Feminino , Síndrome do Túnel Carpal/diagnóstico por imagem , Estudos Prospectivos , Ultrassonografia , Sensibilidade e Especificidade , Nervo Mediano/diagnóstico por imagem , Condução Nervosa
9.
Biomed Opt Express ; 11(12): 7357-7375, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33409002

RESUMO

The effect of sustained fatigue during an upper limb isometric exercise is presented to investigate a group of healthy subjects with simultaneous time-domain (TD) NIRS and surface electromyography (sEMG) recordings on the deltoid lateralis muscle. The aim of the work was to understand which TD-NIRS parameters can be used as descriptors for sustained muscular fatigue, focusing on the slow phase of this process and using median frequency (MF) computed from sEMG as gold standard measure. It was found that oxygen saturation and deoxy-hemoglobin are slightly better descriptors of sustained fatigue, than oxy-hemoglobin, since they showed a higher correlation with MF, while total-hemoglobin correlation with MF was lower.

11.
Neth J Med ; 77(2): 92-96, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30895939

RESUMO

BACKGROUND: The International Committee of Medical Journal Editors (ICMJE) has expressed its concerns about predatory journals using the list of ICMJE Recommendations (ICMJE-R) followers to "gain the appearance of legitimacy." We assessed the presence of potential predatory journals on the ICMJE-R list and their adherence to ICMJE recommendations. METHODS: A random sample of 350 journals from the estimated 3,100-3,200 biomedical journals listed as ICMJE-R followers was chosen. Data collected from the ICMJE and journal webpages in English were: adherence to six ICMJE-R policies/requirements, year of journal's listing as ICMJE-R follower, discipline covered, publisher and its country of origin and existence of article processing charge. Potential predatory journal was considered as one open access journal not being a member of a recognized listing in COPE, DOAJ, OASPA, AJOL and/or INASP. RESULTS: Thirty-one percent of journals were considered to be potentially predatory; 94% of them were included in the ICMJE-R list in 2014-2018. Half were published in the United States and 62% were devoted to medicine. Adherence to five of the six policies/requirements was infrequent, ranging from 51% (plagiarism) to 7% (trial registration). Seventy-two percent of journals mentioned a policy on authors' conflicts of interest. Information on article processing charge was available for 76% journals and could not be found for 22%. Authorship policy/ instructions were significantly more present in journals with publishers from India than from the USA (53% vs 30%; p = 0.047), with no differences in the other five policies. CONCLUSION: Predatory journals should be deleted from the ICMJE-R list of followers to prevent misleading authors. ICMJE-R following journals need to be reevaluated with pre-defined published criteria.


Assuntos
Políticas Editoriais , Publicações Periódicas como Assunto/normas , Bibliometria , Países em Desenvolvimento , Humanos , Revisão por Pares , Estados Unidos
12.
Rev Neurol ; 66(4): 135, 2018 Feb 16.
Artigo em Espanhol | MEDLINE | ID: mdl-29435970

RESUMO

TITLE: Facilitar el acceso a toda la informacion debe ser una obligacion para las revistas medicas.


Assuntos
Acesso à Informação , Publicações Periódicas como Assunto
14.
Rev Neurol ; 65(8): 373-380, 2017 10 16.
Artigo em Espanhol | MEDLINE | ID: mdl-28990648

RESUMO

INTRODUCTION: In 2016 the US Food and Drug Administration (FDA) granted the marketing authorization for eteplirsen for Duchenne muscular dystrophy. This has been a very controversial decision since it happened after a negative assessment from both the Advisory Committee and the technical FDA evaluation team. The FDA's Center for Drug Evaluation and Research (CDER) director was who ultimately approved the product, while the FDA Commissioner did not overrule that decision. AIM: To report about the most relevant events regarding the approval of eteplirsen by the US FDA. DEVELOPMENT: All relevant facts that occurred during the clinical development and evaluation phase following 'accelerated approval' procedure of eteplirsen are discussed in detail. The technical FDA evaluation team reasons supporting that the drug has not proven clinical benefit, the attitude of patient advocacy groups and the post-approval FDA requirements to the marketing authorization holder are discussed. Finally, we reflect on what is the situation Spanish patients face once eteplirsen is on the US market. CONCLUSIONS: This is a unique case in the history of drug authorizations in western countries, that shows the difficulties that current regulations on accelerated approval of new medicines could have when interpreting scarce and low quality clinical development data, when dealing with rare diseases with no available therapies.


TITLE: Asociaciones de pacientes y autorizacion de nuevos farmacos en Estados Unidos. El caso del eteplirseno para la distrofia muscular de Duchenne.Introduccion. En 2016, la Agencia de Medicamentos y Alimentos (FDA) estadounidense autorizo la comercializacion del eteplirseno para el tratamiento de la distrofia muscular de Duchenne. Este hecho ha sido muy controvertido, por cuanto la autorizacion se produjo tras una evaluacion negativa por parte del comite asesor de la FDA y de sus propios tecnicos. Fue la directora del Centro de Investigacion y Evaluacion de Farmacos quien autorizo el medicamento, decision que no revoco el director de la FDA. Objetivo. Informar sobre los acontecimientos mas relevantes que han conducido a la autorizacion del eteplirseno por la FDA. Desarrollo. En el articulo se exponen pormenorizadamente los hechos relevantes que acontecieron durante el desarrollo clinico y la evaluacion reguladora del eteplirseno siguiendo la via de la 'autorizacion acelerada'. Se comentan las razones por las que los tecnicos de la FDA entienden que este medicamento no ha mostrado producir beneficio clinico, la actitud de las asociaciones de pacientes y las exigencias postautorizacion que la FDA ha impuesto a la compañia propietaria del medicamento. Por ultimo, se reflexiona sobre la situacion en que quedan los pacientes espanoles una vez que el eteplirseno esta comercializado en Estados Unidos. Conclusiones. Este caso, unico en la historia de autorizacion de medicamentos en el mundo occidental, pone de manifiesto las dificultades que las regulaciones actuales de autorizacion acelerada de nuevos medicamentos pueden tener en la interpretacion de datos del desarrollo clinico, cuando estos son escasos y de poca calidad, y cuando se trata de enfermedades raras sin terapias disponibles.


Assuntos
Aprovação de Drogas , Morfolinos/uso terapêutico , Distrofia Muscular de Duchenne/tratamento farmacológico , Grupos de Autoajuda , Humanos , Produção de Droga sem Interesse Comercial , Estados Unidos
15.
Int J Obes (Lond) ; 40(11): 1693-1698, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27315439

RESUMO

BACKGROUND/OBJECTIVES: Consumption of high-energy beverages has been implicated as a risk factor for weight gain, yet why nutrients ingested as beverages fail to generate adequate satiety remains unclear. In general, consumers do not expect drinks to be satiating, but drinks generate greater satiety when their sensory characteristics imply they may be filling. These findings challenge traditional bottom-up models of how gut-based satiety signals modify behaviour to suggest that beliefs at the point of ingestion modify gut-based satiety signalling. SUBJECTS/METHODS: Healthy volunteers (n=23) consumed four different beverages, combining an overt sensory manipulation (thin, low sensory (LS) or thicker and more creamy, enhanced sensory (ES)) and covert nutrient manipulation (low energy (LE), 78 kcal; high energy (HE), 267 kcal) on different days. Effects on satiety were assessed through rated appetite and levels of glucose, insulin, pancreatic polypeptide (PP) and cholesystokinin (CCK) recorded periodically over 90 min, and through intake at an ad libitum test lunch. RESULTS: Intake at the test lunch and rated appetite were both altered by both the sensory and nutrient manipulations, with lowest intake and greatest suppression of hunger post-drink in the ESHE condition. Insulin increased more after HE than LE drinks, and after ES than LS drinks, whereas PP levels were higher after ES than LS versions. CCK levels only increased after the ESHE drink. CONCLUSIONS: These data confirm acute sensitivity of satiety after consuming a drink both to the sensory characteristics and nutrient content of the drink, and suggest that this may be, at least in part, due to top-down modulation of release of satiety-related gut hormones.


Assuntos
Apetite/fisiologia , Voluntários Saudáveis , Saciação/fisiologia , Resposta de Saciedade/fisiologia , Adulto , Bebidas , Colecistocinina/metabolismo , Laticínios , Carboidratos da Dieta , Proteínas Alimentares , Ingestão de Energia , Inglaterra , Glucose/metabolismo , Humanos , Insulina/metabolismo , Almoço , Masculino , Pessoa de Meia-Idade , Polipeptídeo Pancreático/metabolismo , Tamanho da Porção/psicologia , Paladar , Viscosidade , Adulto Jovem
16.
Rev Clin Esp (Barc) ; 216(8): 423-426, 2016 Nov.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-27297119

RESUMO

Should medical journals publish editorials and educational articles written by authors who have financial conflicts of interest with pharmaceutical and biotechnology industries on whose products (or their competitors) they discuss? In the last 18 months, a controversy was sparked between The New England Journal of Medicine and BMJ, who took 2 opposite positions: the former stated that the negative bias against authors with conflicts of interest with industry is excessive and therefore accept articles from any expert, ensuring that they have the minimum possible bias. BMJ, in contrast, prohibits the publication of these types of article by authors who have financial conflicts of interest with industry. This article discusses the approaches of the 2 journals (and those of others) and reflects on this type of conflict in the medical profession.

17.
Rev Clin Esp (Barc) ; 215(8): 454-7, 2015 Nov.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-26165166

RESUMO

Clinicians typically update their knowledge by reading articles on the Internet. Easy access to the articles' abstracts and a lack of time to access other information sources creates a risk that therapeutic or diagnostic decisions will be made after reading just the abstracts. Occasionally, however, the abstracts of articles from clinical trials that have not obtained statistically significant differences in the primary study endpoint have reported other positive results, for example, of a secondary endpoint or a subgroup analysis. The article, however, correctly reports all results, including those of the primary endpoint. In the abstract, the safety information of the experimental treatment is usually deficient. The whole article should be read if a clinical decision is to be made.

18.
Physiol Meas ; 36(5): 911-24, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25856085

RESUMO

Heart rate (HR) is a valuable and widespread measure for physical training programs, although its description of conditioning is limited to the cardiac response to exercise. More comprehensive measures of exercise adaptation include cardiac output (Q̇), stroke volume (SV) and oxygen uptake (V̇O2), but these physiological parameters can be measured only with cumbersome equipment installed in clinical settings. In this work, we explore the ability of pulse transit time (PTT) to represent a valuable pairing with HR for indirectly estimating Q̇, SV and V̇O2 non-invasively. PTT was measured as the time interval between the peak of the electrocardiographic (ECG) R-wave and the onset of the photoplethysmography (PPG) waveform at the periphery (i.e. fingertip) with a portable sensor. Fifteen healthy young subjects underwent a graded incremental cycling protocol after which HR and PTT were correlated with Q̇, SV and V̇O2 using linear mixed models. The addition of PTT significantly improved the modeling of Q̇, SV and V̇O2 at the individual level ([Formula: see text] for SV, 0.548 for Q̇, and 0.771 for V̇O2) compared to predictive models based solely on HR ([Formula: see text] for SV, 0.503 for Q̇, and 0.745 for V̇O2). While challenges in sensitivity and artifact rejection exist, combining PTT with HR holds potential for development of novel wearable sensors that provide exercise assessment largely superior to HR monitors.


Assuntos
Exercício Físico/fisiologia , Oxigênio/metabolismo , Fotopletismografia , Análise de Onda de Pulso , Volume Sistólico , Adulto , Transporte Biológico , Feminino , Voluntários Saudáveis , Humanos , Masculino
19.
Pharmacogenomics J ; 15(1): 1-5, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25348616

RESUMO

Whole-genome/exome sequencing used in clinical trials (CTs) to identify 'druggable' mutations and targets uncovers incidental findings unrelated to the trial objectives but of value for participants, although ethically challenging. To be disclosed to trial participants, the analytical validity, clinical validity, clinical utility, clinical relevance and actionability of incidental genomic findings (IGFs) must be established. Special considerations should be taken with minors to disclose only those findings related to early-onset conditions or diseases and in cases where early implementation of measures is necessary to prevent the occurrence of diseases. A plan for disclosing incidental findings that classifies the types that can be found, and who, when and how these findings will be disclosed to participants, should be included in the trial protocol to be approved by the relevant institutional review board. IGFs in CTs raise new ethical challenges that must be discussed by CT stakeholders, professional associations and patient advocates.


Assuntos
Ensaios Clínicos como Assunto/métodos , Estudo de Associação Genômica Ampla/métodos , Genômica/métodos , Achados Incidentais , Gerenciamento Clínico , Humanos
20.
Rev Clin Esp (Barc) ; 214(8): 470-4, 2014 Nov.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-24837147

RESUMO

A clinical trial seeks information for the benefit of future patients and not necessarily for those who participate in the study. However, there are patients who believe that they will receive a direct therapeutic benefit by participating in a clinical trial, the so-called «therapeutic misconception¼. In this article, we describe the nature and extent of therapeutic misconception, which researchers can also experience. Its presence is especially important in phase 1 oncology trials and those with placebo group. To limit its occurrence, investigators have to ensure that participant information sheet are well written and to establish an effective and transparent discussion during the process of obtaining informed consent so that patients understand all aspects of their participation in the research and appreciate what this participation entails.

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