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1.
Comput Biol Med ; 37(5): 663-9, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-16893537

RESUMEN

Cardiotocography (simultaneous recording of fetal heart rate (FHR) and uterine contractions) is one of the most used diagnostic techniques to evaluate fetal well-being and to investigate the functional state of the fetal autonomic nervous system. Recently, great interest has been paid to the variability of the FHR, and its frequency analysis, as a base for a more objective analysis of the cardiotocographic (CTG) tracings. FHR signals are unevenly sampled series. To obtain evenly sampled series, cardiotocographs often use zero-order interpolation. Such process is simple and fast but results unsuitable for frequency analyses because it introduces alterations in the FHR power spectrum. An algorithm for the recovery of the true FHR series out of the zero-order interpolated CTG data was developed and evaluated.


Asunto(s)
Algoritmos , Cardiotocografía/estadística & datos numéricos , Frecuencia Cardíaca Fetal/fisiología , Sistema Nervioso Autónomo/embriología , Bradicardia/fisiopatología , Complejos Cardíacos Prematuros/fisiopatología , Sufrimiento Fetal/fisiopatología , Análisis de Fourier , Humanos , Procesamiento de Señales Asistido por Computador , Taquicardia/fisiopatología
2.
Sci Rep ; 7(1): 10157, 2017 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-28860643

RESUMEN

The molecular details of local plant response against Xanthomonas translucens infection is largely unknown. Moreover, there is no knowledge about effects of the pathogen on the root's transcriptome and proteome. Therefore, we investigated the global gene and protein expression changes both in leaves and roots of wheat (Triticum aestivum) 24 h post leaf infection of X. translucens. This simultaneous analysis allowed us to obtain insight into possible metabolic rearrangements in above- and belowground tissues and to identify common responses as well as specific alterations. At the site of infection, we observed the implication of various components of the recognition, signaling, and amplification mechanisms in plant response to the pathogen. Moreover, data indicate a massive down-regulation of photosynthesis and confirm the chloroplast as crucial signaling hub during pathogen attack. Notably, roots responded as well to foliar attack and their response significantly differed from that locally triggered in infected leaves. Data indicate that roots as a site of energy production and synthesis of various secondary metabolites may actively influence the composition and colonisation level of root-associated microbes. Finally, our results emphasize the accumulation of jasmonic acid, pipecolic acid and/or the downstream mediator of hydrogen peroxide as long distal signals from infected leaves to roots.


Asunto(s)
Proteoma/genética , Transcriptoma , Triticum/genética , Xanthomonas/patogenicidad , Cloroplastos/metabolismo , Cloroplastos/microbiología , Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Ácidos Pipecólicos/metabolismo , Hojas de la Planta/metabolismo , Hojas de la Planta/microbiología , Raíces de Plantas/metabolismo , Raíces de Plantas/microbiología , Proteoma/metabolismo , Triticum/microbiología
3.
Med Biol Eng Comput ; 44(3): 188-201, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16937160

RESUMEN

Cardiotocography is the most diffused prenatal diagnostic technique in clinical routine. The simultaneous recording of foetal heart rate (FHR) and uterine contractions (UC) provides useful information about foetal well-being during pregnancy and labour. However, foetal electronic monitoring interpretation still lacks reproducibility and objectivity. New methods of interpretation and new parameters can further support physicians' decisions. Besides common time-domain analysis, study of the variability of FHR can potentially reveal autonomic nervous system activity of the foetus. In particular, it is clinically relevant to investigate foetal reactions to UC to diagnose foetal distress early. Uterine contraction being a strong stimulus for the foetus and its autonomic nervous system, it is worth exploring the FHR variability response. This study aims to analyse modifications of the power spectrum of FHR variability corresponding to UC. Cardiotocographic signal tracts corresponding to 127 UC relative to 30 healthy foetuses were analysed. Results mainly show a general, statistically significant (t test, p<0.01) power increase of the FHR variability in the LF 0.03-0.2 Hz and HF 0.2-1 in correspondence of the contraction with respect to a reference tract set before contraction onset. Time evolution of the power within these bands was computed by means of time-varying spectral estimation to concisely show the FHR response along a uterine contraction. A synchronised grand average of these responses was also computed to verify repeatability, using the contraction apex as time reference. Such modifications of the foetal HRV that follow a contraction can be a sign of ANS reaction and, therefore, additional, objective information about foetal reactivity during labour.


Asunto(s)
Frecuencia Cardíaca Fetal/fisiología , Contracción Uterina/fisiología , Sistema Nervioso Autónomo/embriología , Cardiotocografía/métodos , Femenino , Análisis de Fourier , Edad Gestacional , Humanos , Embarazo , Procesamiento de Señales Asistido por Computador
4.
Chemosphere ; 52(7): 1183-8, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12820999

RESUMEN

In recent years several plant species have been in use as bioindicators and several tests have been developed to evaluate the toxicity of environmental pollutants in vegetal organisms. In the present paper Arabidopsis thaliana (L.) Heynh. (ecotype Wassilewskija) was used as bioindicators of two genotoxic substances: potassium dichromate and dihydrophenanthrene. Inhibition of seed germination was observed with both pollutants. AFLP analysis (i) indicated that both substances are genotoxic, (ii) showed that dihydrophenanthrene induces DNA changes in different target sequences than potassium dichromate, (iii) quantified the genotoxic effect using cluster analysis by comparing DNA from treated plants with that of control plants. On the basis of these considerations we suggest that AFLP method is a powerful tool for measuring qualitative and quantitative genotoxic activity due to environmental pollutants. AFLP method can be applied to a wide range of bioindicator organisms and may become a universal methodology to identify target genes for specific genotoxic agents. This could open up possibilities for designing specifically targeted assays and new approaches to risk assessment.


Asunto(s)
Arabidopsis/efectos de los fármacos , ADN de Plantas/genética , Contaminantes Ambientales/toxicidad , Compuestos Inorgánicos/toxicidad , Compuestos Orgánicos/toxicidad , Arabidopsis/genética , Pruebas de Mutagenicidad , Polimorfismo de Longitud del Fragmento de Restricción , Técnica del ADN Polimorfo Amplificado Aleatorio , Semillas/efectos de los fármacos , Semillas/genética
5.
Med Biol Eng Comput ; 32(2): 131-7, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8022208

RESUMEN

The authors report the results of a feasibility study, sponsored by the Italian Foreign Ministry, of setting up a Regional Centre for the Management and Maintenance of Medical Technologies in Ethiopia. After some general considerations regarding the problems of co-operation in this field, the authors draft some concrete proposals for an operative programme.


Asunto(s)
Equipos y Suministros , Ciencia del Laboratorio Clínico/organización & administración , Equipos y Suministros/provisión & distribución , Etiopía , Estudios de Factibilidad , Directrices para la Planificación en Salud , Humanos , Cooperación Internacional , Mantenimiento/organización & administración , Ciencia del Laboratorio Clínico/educación
6.
Med Biol Eng Comput ; 39(1): 65-75, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11214275

RESUMEN

Intervertebral kinematics closely relates to the functionality of the spinal segments. Direct measurement of the intervertebral kinematics in vivo is very problematic. The use of a fluoroscopic device can provide continuous screening of the lumbar tract during patient spontaneous motion, with an acceptable, low X-ray dose. The kinematic analysis is intended to be limited to planar motion. Kinematic parameters are computed from vertebral landmarks on each frame of the image sequence. Landmarks are normally selected manually in spite of the fact that this is subjective, tedious to perform and regarded as one of the major contributors to errors in the computed kinematic parameters. The aim of this work is to present an innovative method for the automatic recognition of vertebral landmarks throughout a fluoroscopic image sequence to provide an objective and more precise quantification of intervertebral kinematics. The recognition procedure is based upon comparing vertebral features in two adjacent frames by means of a cross-correlation index, which is also robust despite the low signal-to-noise ratio of the lumbar fluoroscopic images. To provide a quantitative assessment of this method a calibration model was used which consisted of two lumbar vertebrae linked by a universal joint. The reliability and accuracy of the kinematic measurements have been investigated. The errors are of the order of a millimetre for the localisation of the intervertebral centre of rotation and tenths of a degree for the intervertebral angle. Error analysis suggests that this method improves the accuracy of the intervertebral kinematic calculations and has the potential to automate the selection of anatomical landmarks.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Movimiento/fisiología , Columna Vertebral/fisiología , Calibración , Fluoroscopía , Humanos
7.
Med Eng Phys ; 21(6-7): 469-78, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10624742

RESUMEN

The aim of this paper is to study the femoral quadriceps muscles activation in patients suffering from anterior knee pain (AKP) during an isokinetic exercise. AKP is a common pathological condition, associated to an abnormal motion of the patella. It possibly depends on a muscular or structural imbalance. A lack of synergy in the quadriceps muscles results in a dynamic misalignment of the patella, which in turn produces pain. A quantitative analysis of the muscle activation strategy is important for an objective measurement of the knee functionality in that it helps to diagnose and monitor the rehabilitative treatment. Surface electromyography (EMG) from the three superficial muscles of the femoral quadriceps during a concentric isokinetic exercise has been analysed. A group of AKP patients has been compared with a control group of healthy subjects. Ensemble average of the EMG linear envelopes reveals significant modifications in Vastus Medialis activity in AKP patients. In order to quantify the synergy of the muscles, different parameters have been associated to EMG linear envelopes significant features. A decomposition in gaussian pulses and an asymmetry coefficient have been utilised. The results relative to these concise parameters highlight an appreciable delay and a modification in the activation of the Vastus Medialis in AKP patients.


Asunto(s)
Artralgia/fisiopatología , Ejercicio Físico/fisiología , Articulación de la Rodilla/fisiopatología , Músculo Esquelético/fisiopatología , Adolescente , Adulto , Electromiografía/instrumentación , Electromiografía/métodos , Electromiografía/estadística & datos numéricos , Humanos , Masculino , Valores de Referencia , Procesamiento de Señales Asistido por Computador/instrumentación , Factores de Tiempo
8.
J Telemed Telecare ; 3(1): 53-8, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9139762

RESUMEN

Electronic newspapers are now becoming available via wide-area computer networks, such as the internet. Unfortunately, the Windows-based graphical user interface of the client programs makes it difficult for visually impaired people to use such services. Furthermore, few visually impaired people have a PC. The AUDIOMAT project was designed to provide a reading system for the visually impaired, thus giving this community in the Campania region of southern Italy the opportunity to read their local newspaper. In a pilot trial, three blind subjects used the AUDIOMAT system daily for two months. Despite some minor technical problems the system performed well and a wider validation phase is now planned.


Asunto(s)
Redes de Comunicación de Computadores , Periódicos como Asunto , Lectura , Baja Visión , Humanos , Italia , Proyectos Piloto
9.
Technol Health Care ; 6(2-3): 111-23, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9839857

RESUMEN

In the last few years, Functional Magnetic Resonance Imaging (fMRI) has been widely accepted as an effective tool for mapping brain activities in both the neurosensorial and the cognitive field. The present work aims to assess the possibility of using fMRI methods to perform a non-invasive evaluation of the human auditory function. To this end the cortical response to different non speech stimuli (pure tones, pulsed tones) was examined for ten subjects with no audiological impairment. Our findings point out some remarkable differences in both the spatial and the temporal features of the primary auditory cortex response to pulsed tones and to pure tones.


Asunto(s)
Corteza Auditiva/fisiología , Percepción Auditiva/fisiología , Mapeo Encefálico/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Procesamiento de Señales Asistido por Computador , Adulto , Audiometría de Tonos Puros , Corteza Auditiva/irrigación sanguínea , Velocidad del Flujo Sanguíneo , Análisis de los Gases de la Sangre , Volumen Sanguíneo , Circulación Cerebrovascular , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados
10.
Methods Inf Med ; 50(5): 435-44, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21132218

RESUMEN

BACKGROUND: A gap exists between evidence-based medicine and clinical-practice. Every day, healthcare professionals (HCPs) combine empirical evidence and subjective experience in order to maximize the effectiveness of interventions. Consequently, it is important to understand how HCPs interpret the research evidence and apply it in everyday practice. We focused on the prevention of falls, a common cause of injury-related morbidity and mortality in later life, for which there is a wide range of known risk factors. OBJECTIVES: To use the Analytic Hierarchy Process (AHP) to investigate the opinions of HCPs in prioritizing risk factors for preventing falls. METHODS: We used the AHP to develop a hierarchy of risk factors for falls based on the knowledge and experience of experts. We submitted electronic questionnaires via the web, in order to reach a wider number of respondents. With a web service, we pooled the results and weighted the coherence and the experience of respondents. RESULTS: Overall, 232 respondents participated in the study: 32 in the technical pilot study, nine in the scientific pilot study and 191 respondents in the main study. We identified a hierarchy of 35 risk factors, organized in two categories and six sub-categories. CONCLUSIONS: The hierarchy of risk factors provides further insights into clinicians' perceptions of risk factors for falls. This hierarchy helps understand the relative importance that clinicians place on risk factors for falls in older people and why evidence-based guidelines are not always followed. This information may be helpful in improving intervention programs and in understanding how clinicians prioritize multiple risk factors in individual patients. The AHP method allows the opinions of HCPs to be investigated, giving appropriate weight to their coherence, background and experience.


Asunto(s)
Accidentes por Caídas/prevención & control , Toma de Decisiones , Pautas de la Práctica en Medicina , Características de la Residencia , Factores de Riesgo , Accidentes Domésticos , Factores de Edad , Algoritmos , Docentes , Humanos , Enfermeras y Enfermeros , Fisioterapeutas , Médicos , Proyectos Piloto , Encuestas y Cuestionarios
11.
Phytochemistry ; 72(14-15): 1786-95, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21708391

RESUMEN

The present study is aimed at identifying molecular changes elicited by Cr(III) and Cr(VI) on germinating kiwifruit pollen. To address this question, comparative proteomic and DNA laddering analyses were performed. While no genotoxic effect was detected, a number of proteins whose accumulation levels were altered by treatments were identified. In particular, the upregulation of some proteins involved in the scavenging response, cell redox homeostasis and lipid synthesis could be interpreted as an oxidative stress response induced by Cr treatment. The strong reduction of two proteins involved in mitochondrial oxidative phosphorylation and a decline in ATP levels were also observed. The decrease of pollen energy availability could be one of the causes of the severe inhibition of the pollen germination observed upon exposure to both Cr(III) and Cr(VI). Finally, proteomic and biochemical data indicate proteasome impairment: the consequential accumulation of misfolded/damaged proteins could be an important molecular mechanism of Cr(III) toxicity in pollen.


Asunto(s)
Actinidia/metabolismo , Cromo/farmacología , Polen/metabolismo , Proteómica/métodos , Actinidia/efectos de los fármacos , Adenosina Trifosfato/análisis , Adenosina Trifosfato/metabolismo , Daño del ADN/efectos de los fármacos , ADN de Plantas/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Estrés Oxidativo/efectos de los fármacos , Polen/efectos de los fármacos , Complejo de la Endopetidasa Proteasomal/efectos de los fármacos , Complejo de la Endopetidasa Proteasomal/metabolismo , Estrés Fisiológico/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacos
19.
Front Med Biol Eng ; 4(3): 157-67, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1419915

RESUMEN

In the last years a new approach to cooperation programmes with developing countries has been followed. It critically considers cooperation as donation and makes a big contribution to cooperation for the development of developing countries. For such reasons some topics such as 'education' and the 'management of the health services and technologies' have become more important than in the past. The authors report, first on some general aspects of the cooperation programmes in this field and, secondly, on some experiences relating to a cooperation programme for the management of medical technologies in Ethiopia.


Asunto(s)
Cooperación Internacional , Ciencia del Laboratorio Clínico/organización & administración , Países en Desarrollo , Seguridad de Equipos , Etiopía , Estudios de Factibilidad , Mantenimiento , Ciencia del Laboratorio Clínico/educación , Ciencia del Laboratorio Clínico/normas , Proyectos Piloto
20.
IEEE Trans Rehabil Eng ; 4(4): 410-5, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8973967

RESUMEN

Exercise is the central feature in the rehabilitative treatment of hemiplegic patients. In cognitive rehabilitation, great importance is attributed to the recovery of a sufficient number of proprioceptive channels before expecting the patient to regain voluntary control. The PERM [Piattaforma (Platform), Elettropneumatica (Electropneumatic) per (for) Riabilitazione (Rehabilitation) Motoria (Motor)] is a new device that can be used in the treatment of the lower limbs to provide the patient with controlled and quantifiable mechanical stimuli, thus enabling the therapist to adopt a more rigorous approach to treatment even in the very early stages of rehabilitation. Alternatively, the system can be used in a different operating mode as a normal biofeedback system capable of displaying on-screen the extent to which voluntary load has been transferred to the lower limb.


Asunto(s)
Terapia Cognitivo-Conductual/instrumentación , Diseño Asistido por Computadora , Terapia por Ejercicio , Hemiplejía/rehabilitación , Programas Informáticos , Terapia Cognitivo-Conductual/métodos , Terapia por Ejercicio/métodos , Hemiplejía/terapia , Humanos , Pierna/fisiopatología , Modelos Teóricos
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