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1.
Opt Express ; 31(12): 19733-19745, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37381382

RESUMEN

Knowledge of spatio-temporal couplings such as pulse-front tilt or curvature is important to determine the focused intensity of high-power lasers. Common techniques to diagnose these couplings are either qualitative or require hundreds of measurements. Here we present both a new algorithm for retrieving spatio-temporal couplings, as well as novel experimental implementations. Our method is based on the expression of the spatio-spectral phase in terms of a Zernike-Taylor basis, allowing us to directly quantify the coefficients for common spatio-temporal couplings. We take advantage of this method to perform quantitative measurements using a simple experimental setup, consisting of different bandpass filters in front of a Shack-Hartmann wavefront sensor. This fast acquisition of laser couplings using narrowband filters, abbreviated FALCON, is easy and cheap to implement in existing facilities. To this end, we present a measurement of spatio-temporal couplings at the ATLAS-3000 petawatt laser using our technique.

2.
Z Gastroenterol ; 53(12): 1414-21, 2015 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-26666278

RESUMEN

Direct acting antivirals (DAAs) have increased cure rates for chronic hepatitis C infection up to nearly 100 %. At the same time treatment costs have risen significantly. Treating all HCV infected patients in Germany with DAAs would generate medication costs ranging between 19 and 37 billion EUR depending on the drug regimen used. Expenses in patients who fail to respond to treatment would amount to approximately 0.9 to 2.15 billion EUR. In difficult to treat patient populations that are characterized by prior failure to treatment or advanced liver disease, lost drug expenses are particularly high due to lower cure rates and longer treatment duration. Outcome-based reimbursement schemes are used to improve the quality of care and to reduce costs in the health care system. In Germany, disease management programs have been implemented for defined chronic diseases. However, drug reimbursement is still based on packages sold (pay for pill). In this context, it would be appealing to link reimbursement and treatment success (pay for cure) in order to reward successful treatment, limit lost drug spending and develop a shared risk environment that would involve all concerned parties. Under the assumption that 20,000 patients with HCV are treated each year in Germany and that cure rates are 95.4 %, the saved treatment costs would amount up to 45 and 107 million EUR per year. By this approach, economic incentives to withhold therapy from difficult to treat patients could be avoided.


Asunto(s)
Fármacos Anti-VIH/economía , Análisis Costo-Beneficio/economía , Hepatitis C/tratamiento farmacológico , Hepatitis C/economía , Modelos Económicos , Reembolso de Incentivo/economía , Fármacos Anti-VIH/uso terapéutico , Análisis Costo-Beneficio/métodos , Honorarios y Precios/estadística & datos numéricos , Femenino , Alemania/epidemiología , Costos de la Atención en Salud/estadística & datos numéricos , Hepatitis C/epidemiología , Humanos , Masculino , Prevalencia , Reembolso de Incentivo/estadística & datos numéricos
3.
Acad Radiol ; 30 Suppl 1: S143-S154, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37095047

RESUMEN

RATIONALE AND OBJECTIVES: Hepatocellular carcinoma (HCC) is the only tumor entity that allows non-invasive diagnosis based on imaging without further histological proof. Therefore, excellent image quality is of utmost importance for HCC diagnosis. Novel photon-counting detector (PCD) CT improves image quality via noise reduction and higher spatial resolution, inherently providing spectral information. The aim of this study was to investigate these improvements for HCC imaging with triple-phase liver PCD-CT in a phantom and patient population study focusing on identification of the optimal reconstruction kernel. MATERIALS AND METHODS: Phantom experiments were performed to analyze objective quality characteristics of the regular body and quantitative reconstruction kernels, each with four sharpness levels (36-40-44-48). For 24 patients with viable HCC lesions on PCD-CT, virtual monoenergetic images at 50 keV were reconstructed using these kernels. Quantitative image analysis included contrast-to-noise ratio (CNR) and edge sharpness. Three raters performed qualitative analyses evaluating noise, contrast, lesion conspicuity, and overall image quality. RESULTS: In all contrast phases, the CNR was highest using the kernels with a sharpness level of 36 (all p < 0.05), with no significant influence on lesion sharpness. Softer reconstruction kernels were also rated better regarding noise and image quality (all p < 0.05). No significant differences were found in image contrast and lesion conspicuity. Comparing body and quantitative kernels with equal sharpness levels, there was no difference in image quality criteria, neither regarding in vitro nor in vivo analysis. CONCLUSION: Soft reconstruction kernels yield the best overall quality for the evaluation of HCC in PCD-CT. As the image quality of quantitative kernels with potential for spectral post-processing is not restricted compared to regular body kernels, they should be preferred.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Fantasmas de Imagen
4.
Sci Rep ; 13(1): 11680, 2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37468564

RESUMEN

In recent years, significant progress has been made in laser wakefield acceleration (LWFA), both regarding the increase in electron energy, charge and stability as well as the reduction of bandwidth of electron bunches. Simultaneous optimization of these parameters is, however, still the subject of an ongoing effort in the community to reach sufficient beam quality for next generation's compact accelerators. In this report, we show the design of slit-shaped gas nozzles providing centimeter-long supersonic gas jets that can be used as targets for the acceleration of electrons to the GeV regime. In LWFA experiments at the Centre for Advanced Laser Applications, we show that electron bunches are accelerated to [Formula: see text] using these nozzles. The electron bunches were injected into the laser wakefield via a laser-machined density down-ramp using hydrodynamic optical-field-ionization and subsequent plasma expansion on a ns-timescale. This injection method provides highly controllable quasi-monoenergetic electron beams with high charge around [Formula: see text], low divergence of [Formula: see text], and a relatively small energy spread of around [Formula: see text] at [Formula: see text]. In contrast to capillaries and gas cells, the scheme allows full plasma access for injection, probing or guiding in order to further improve the energy and quality of LWFA beams.

6.
Breast ; 45: 22-28, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30822621

RESUMEN

BACKGROUND: This multicenter, double-blind phase II study assessed the antitumor activity and toxicity profile of docetaxel with the antiangiogenic multikinase inhibitor sorafenib or matching placebo as a first-line treatment in patients with metastatic or locally advanced HER2-negative breast cancer. PATIENTS AND METHODS: Patients were randomized 1:1 to receive docetaxel 100 mg/m2 on day 1 every 3 weeks in combination with sorafenib 400 mg bid or placebo on days 2-18 of each cycle until tumor progression, or unacceptable toxicity. Sorafenib/placebo could be continued at the investigator's discretion if docetaxel was stopped due to toxicity. Primary endpoint was progression free survival (PFS). RESULTS: From October 2008 to December 2013, 102 patients were randomized; 98 patients were evaluable. The trial was prematurely terminated due to slow accrual. Due to increased toxicity the dose of docetaxel was reduced to 75 mg/m2 and an increasing sorafenib dosing schedule was implemented as part of a protocol amendment. The addition of sorafenib to docetaxel did not improve PFS (8.2 vs. 7.3 months for docetaxel/placebo; HR 0.84, log rank p = 0.43), but led to higher rates of early treatment discontinuation. There were no statistically significant differences between sorafenib dosing schedules. CONCLUSIONS: Addition of sorafenib to taxane-based first-line chemotherapy in patients with metastatic breast cancer failed to improve PFS and resulted in increased toxicity.


Asunto(s)
Inhibidores de la Angiogénesis/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Neoplasias de la Mama/tratamiento farmacológico , Docetaxel/administración & dosificación , Sorafenib/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/metabolismo , Método Doble Ciego , Esquema de Medicación , Femenino , Humanos , Persona de Mediana Edad , Supervivencia sin Progresión , Receptor ErbB-2/metabolismo , Resultado del Tratamiento
7.
Oncoimmunology ; 8(8): 1615817, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31413923

RESUMEN

Pexastimogene devacirepvec (Pexa-Vec) is a vaccinia virus-based oncolytic immunotherapy designed to preferentially replicate in and destroy tumor cells while stimulating anti-tumor immunity by expressing GM-CSF. An earlier randomized Phase IIa trial in predominantly sorafenib-naïve hepatocellular carcinoma (HCC) demonstrated an overall survival (OS) benefit. This randomized, open-label Phase IIb trial investigated whether Pexa-Vec plus Best Supportive Care (BSC) improved OS over BSC alone in HCC patients who failed sorafenib therapy (TRAVERSE). 129 patients were randomly assigned 2:1 to Pexa-Vec plus BSC vs. BSC alone. Pexa-Vec was given as a single intravenous (IV) infusion followed by up to 5 IT injections. The primary endpoint was OS. Secondary endpoints included overall response rate (RR), time to progression (TTP) and safety. A high drop-out rate in the control arm (63%) confounded assessment of response-based endpoints. Median OS (ITT) for Pexa-Vec plus BSC vs. BSC alone was 4.2 and 4.4 months, respectively (HR, 1.19, 95% CI: 0.78-1.80; p = .428). There was no difference between the two treatment arms in RR or TTP. Pexa-Vec was generally well-tolerated. The most frequent Grade 3 included pyrexia (8%) and hypotension (8%). Induction of immune responses to vaccinia antigens and HCC associated antigens were observed. Despite a tolerable safety profile and induction of T cell responses, Pexa-Vec did not improve OS as second-line therapy after sorafenib failure. The true potential of oncolytic viruses may lie in the treatment of patients with earlier disease stages which should be addressed in future studies. ClinicalTrials.gov: NCT01387555.

8.
J Consult Clin Psychol ; 64(3): 439-46, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8698935

RESUMEN

The steps of a task-analytic research program designed to identify the in-session performances involved in resolving lingering bad feelings toward a significant other are described. A rational-empirical methodology of repeatedly cycling between rational conjecture and empirical observations is demonstrated as a method of developing an intervention manual and the components of client processes of resolution. A refined model of the change process developed by these procedures is validated by comparing 11 successful and 11 unsuccessful performances. Four performance components-intense expression of feeling, expression of need, shift in representation of other, and self-validation or understanding of the other-were found to discriminate between resolution and nonresolution performances. These components were measured on 4 process measures: the Structural Analysis of Social Behavior, the Experiencing Scale, the Client's Emotional Arousal Scale, and a need scale.


Asunto(s)
Adaptación Psicológica , Relaciones Interpersonales , Psicoterapia/métodos , Adulto , Femenino , Terapia Gestalt/métodos , Humanos , Masculino , Manuales como Asunto , Determinación de la Personalidad , Conducta Social , Resultado del Tratamiento
9.
Biol Psychol ; 21(3): 169-82, 1985 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-4084625

RESUMEN

A sample of 58 students was subjected to four stress conditions (mental arithmetic, reaction time, free speech, cold-pressor test). Eight physiological variables (skin conductance, heart rate, pulse amplitude, Heather index, eye blinking, horizontal eye movements, respiration rate, blood pressure) and five psychological variables (self-rated anger, irritability, tenseness, motivation, indifference) were monitored. Proportions of variance in a three-factor ANOVA (subjects, situations, variables) accounted for by individual specific response patterns (ISR) amounted to 33-40% for physiological and 9-13% for psychological variables. Stimulus specific response patterns (SSR) accounted for 11-19% for physiological and 8-14% for psychological variables, and motivation specific response patterns (MSR) for 17% for physiological and 14-16% for psychological variables. About one-fourth of the subjects showed a rather stable ISR in physiological variables when tested again after two months, and about 14% when tested again after twelve months. Overall, the results replicated earlier findings from this laboratory.


Asunto(s)
Estrés Fisiológico/fisiopatología , Estrés Psicológico/fisiopatología , Adaptación Fisiológica , Adulto , Estudios de Seguimiento , Humanos , Masculino , Estadística como Asunto , Estrés Fisiológico/psicología , Estrés Psicológico/psicología , Factores de Tiempo
10.
Biol Psychol ; 22(3): 227-37, 1986 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3756285

RESUMEN

The well-known negative correlation between initial value and difference score, referred to as the law of initial value (LIV), is analyzed in the present study. It is shown that whenever the correlation between the initial and final values is less than 1.00, the negative correlation is influenced by the a(a - b) effect. By relating values to the first principal component axis, this spurious effect can be eliminated, thus allowing analysis of any real dependency on initial values. Data collected in a psychophysiological experiment were used to test this hypothesis. A subject sample of 125 male students experienced various challenges (Cold Pressor Test, breath holding, reaction time measurement, digit-series test) while several physiological variables (e.g. blood pressure, stroke volume, electrodermal activity) were monitored. Results fail to support the LIV as originally advanced by Wilder. On the contrary, after eliminating the a(a - b) effect, a positive dependency as indicated by the slope of the first principal component axis (anti-LIV) was observed. The reciprocal relationship between the LIV and anti-LIV is discussed with respect to the measures employed. Advantages and disadvantages of various methods to correct for the initial value dependency are presented.


Asunto(s)
Nivel de Alerta/fisiología , Adulto , Atención/fisiología , Humanos , Masculino , Matemática , Psicofisiología , Tiempo de Reacción/fisiología
11.
Biol Psychol ; 15(3-4): 151-69, 1982.
Artículo en Inglés | MEDLINE | ID: mdl-7159643

RESUMEN

Individual differences in activation processes, as well as the consistency and predictability of these differences, constitute a classical issue eliciting much theoretical discussion in this field and as such poses an essential question for any practical application of psychophysiological methods. A typical activation experiment assessing 125 male students on four self-report and 21 physiological measures under five conditions (rest, mental arithmetic, interview, anticipation and blood taking) was performed supplying an empirical basis for a multivariate analysis. A partition of covariance, factor analyses, item analyses and scale construction procedures as well as models engaging an increasing number of components were used to study the covariation and consistency of these activation parameters. Several biometric problems that are generally thought to complicate the evaluation of such data (i.e. non-linear relations, the problem of initial values, differing sensibility curves of physiological response systems, individual response specificities) are considered and tested empirically. Findings suggest that the use of a single variable or a composite measure as an 'indicator' of individual differences in state or reaction aspects of activation is inadequate, due to empirical inconsistency and the lack of predictability between functional subsystems. A multicomponent model or a set of marker variables, having empirically derived discriminative efficiency as well as reliability estimates, seem to be preferable.


Asunto(s)
Nivel de Alerta/fisiología , Análisis de Varianza , Presión Sanguínea , Electroencefalografía , Electromiografía , Frecuencia Cardíaca , Humanos , Personalidad , Psicofisiología
12.
Biol Psychol ; 35(3): 225-35, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8218615

RESUMEN

Relationships between the time series of five physiological sleep parameters were examined and related to sleep quality. Twenty-eight male coronary patients participated in the investigation. Recordings were carried out with a mobile device consisting of two Medilog 4-24 recorders and one DMI-recorder assessing five biosignals: EEG, EOG, EMG, ECG and body movements. Relationships between the time series of physiological sleep parameters were obtained by partitioning of covariance. The investigation showed that substantial relationships exist between the time series of the EEG, the number of eye movements and heart rate. Moreover, the time series of body movements showed substantial relationships to the time series of the EMG and heart rate. High correlations between the time series of the EEG and heart rate were related to a better sleep quality.


Asunto(s)
Nivel de Alerta/fisiología , Enfermedad Coronaria/fisiopatología , Polisomnografía , Fases del Sueño/fisiología , Adulto , Cateterismo Cardíaco , Corteza Cerebral/fisiopatología , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Persona de Mediana Edad , Actividad Motora/fisiología , Procesamiento de Señales Asistido por Computador
13.
Biol Psychol ; 17(1): 1-26, 1983 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-6626634

RESUMEN

The role of specific response patterns obtained by means of psychophysiological activation and their temporal stability are meeting with an increasing interest in the literature because of a low correlation between psychophysiological variables and of possible implications with regard to pathogenetic mechanisms in psychosomatic disease. Two empirical studies are presented that were conducted under similar stress conditions (mental arithmetic, free speech, cold-pressor test, blood-taking) and have been monitoring similar activation variables (seven physiological and four or five psychological variables) - one of which using a large sample of 125 students, the other one consisting of 47 students, who were tested three times week- by-week. Findings reveal that substantial proportions of variance in the three-factorial ANOVA (subjects, situations, variables) may be considered on the basis of individual-specific (23-29% for physiological variables, 6-11% for psychological variables), stimulus-specific (5-19% for physiological variables, 1-11% for psychological variables), and motivation-specific (21% for physiological variables, 10% for psychological variables) response patterns. Five evaluation procedures on nominal, ordinal, and interval data levels as well as various definitions of similarity found in the reaction patterns are used in a comprehensive approach to the analysis of specificities. Estimation of variance components, global tests, and individual tests are applied. The results prove to be reliable and rather stable, at least over a period of several weeks. In total, about one fourth of the subjects show a stable individual-specific response pattern on physiological variables. The results are discussed with respect to data and sampling problems as well as to various methods of data analysis.


Asunto(s)
Estrés Fisiológico/fisiopatología , Estrés Psicológico/fisiopatología , Adulto , Electrocardiografía , Electroencefalografía , Electromiografía , Emociones , Dedos/irrigación sanguínea , Respuesta Galvánica de la Piel , Frecuencia Cardíaca , Humanos , Individualidad , Masculino , Motivación , Psicofisiología , Respiración , Temperatura Cutánea , Estrés Fisiológico/psicología , Estrés Psicológico/psicología
14.
Biol Psychol ; 55(1): 25-39, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11099806

RESUMEN

Schizophrenic patients and their first-degree relatives exhibit deficits in the anti-saccade task. In the present study, anti-saccade task performance was examined in subjects with 'high' and 'low' expressions of the schizotypal personality trait. For that purpose, the SPQ-G, the German adaptation of the Schizotypal Personality Questionnaire (SPQ; Raine, 1991), was filled in by 489 university students. Twenty and 21 participants with 'high' and 'low' SPQ-G scores, respectively, were compared with respect to saccadic eye movements elicited under the overlap and 200 ms gap conditions of the pro- and anti-saccade tasks. Each task block comprised 150 trials, 75 to either side in random order. The order of presentation of the task blocks was counterbalanced across the participants of each group. Saccadic reaction times were slower during the anti- as compared to the pro-saccade task and under the overlap as compared to the gap condition. Direction errors occurred almost exclusively during the anti-saccade task, express saccades mainly under the pro-saccadic gap condition. High-schizotypal participants did not differ significantly from low-schizotypal participants in any of these measures. While these results might suggest normal anti-saccade task performance in schizotypal personality as defined by the SPQ-G, the sampling strategy adopted in the present study is the more plausible explanation for the lack of group differences.


Asunto(s)
Movimientos Sacádicos/fisiología , Trastorno de la Personalidad Esquizotípica/diagnóstico , Trastorno de la Personalidad Esquizotípica/fisiopatología , Adulto , Señales (Psicología) , Femenino , Humanos , Masculino , Psicometría/estadística & datos numéricos , Tiempo de Reacción , Encuestas y Cuestionarios
15.
Biol Psychol ; 16(3-4): 241-53, 1983.
Artículo en Inglés | MEDLINE | ID: mdl-6615956

RESUMEN

A procedure for measuring tonic and phasic reaction components of skin evaporative water loss (SE) on the basis of a capacitive measurement principle is developed and used in a psychophysiological study employing various stimulus conditions. SE and skin conductance (SC) are registered continuously to obtain comparative data of both biosignals for research concerning the underlying mechanisms of EDA. Results indicate that correlations of some phasic parameters of SC and SE prove to be rather high (up to 0.88), tonic parameters (the levels SCL and SEL), however, show less covariance (0.44). The intersituational discriminative efficiency of SC-parameters appears generally better than those of SE. SCL, as well as SEL, show the highest percentage of person variance. A rather high redundancy of the two biosignals, both taken from neighbouring areas of the right palm, has been found. An unexplicable residual may, however, lend some support to the notion of a partial independence of EDA from sweating.


Asunto(s)
Nivel de Alerta/fisiología , Respuesta Galvánica de la Piel/fisiología , Pérdida Insensible de Agua , Adulto , Humanos , Masculino , Psicofisiología , Tiempo de Reacción/fisiología , Sudoración
16.
Artículo en Inglés | MEDLINE | ID: mdl-10076756

RESUMEN

Clinical tremor analysis mostly is used for the measurement of tremor frequency. The analysis is based on short segments of EMG recordings and on clinical ratings of tremor intensity. Accelerometry appears to have some practical advantages. The present study was concerned with the development of a methodology for assessing tremor activity using the three parameters, frequency (Hz), amplitude (g), and occurrence of tremor (in per cent of time). These parameters were derived from joint amplitude frequency analysis of the calibrated accelerometer raw signal and from appropriate decision rules. This methodology was used in connection with 27 patients with Parkinson's disease, to investigate the aforesaid parameters of tremor activity. Postural tremor had a higher occurrence time (right-hand only) and higher frequency (left-hand only) than resting tremor, however, the average amplitudes did not differ. The correlations between right-hand and left-hand measures were higher during postural tremor test. Frequency was not correlated to amplitude or occurrence time, however, moderate correlations did exist between amplitude and occurrence time. In addition to the assessment of tremor activity, multi-channel accelerometry may be used for the detection of posture and motion. Further applications of this methodology, for example, in 24 hr ambulatory monitoring of tremor, are discussed.


Asunto(s)
Electromiografía/clasificación , Enfermedad de Parkinson/fisiopatología , Temblor/fisiopatología , Aceleración , Anciano , Anciano de 80 o más Años , Calibración , Femenino , Análisis de Fourier , Mano/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Ambulatorio , Movimiento (Física) , Postura/fisiología , Descanso/fisiología , Procesamiento de Señales Asistido por Computador , Factores de Tiempo
17.
Electromyogr Clin Neurophysiol ; 44(3): 137-46, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15125053

RESUMEN

Monitoring systems enable the long-term registration of tremor in patients with Parkinson's disease This method is useful in the objective measurement of tremor during the course of treatments. Indeed, the symptoms of tremor as well as the aggravating and attenuating influences can be observed under real-life conditions. The methodology of data recording and analysis, described in previous investigations, was extended to automatically detect body position and certain movement patterns with calibrated 4-channel accelerometry. The main purpose of the present investigation was to apply this refined and extended methodology to patients in a clinical rehabilitation program, and to examine its practability with respect to the results of the treatment and the patients' compliance. The methodology was tested on 30 patients (17 male, 13 female) with Parkinson's disease. The mean age was 64.8 years (s = 8.9). The Hoehn-Yahr index ranged from 1 to 3 (m = 2.3, s = 0.7) and the overall UPDRS scale between 10 and 74 (m = 42.9, s = 18.1). The data recording included: (1) the registration of tremor under standardised conditions of rest and postural tremor test with and without distraction; (2) a standard protocol to obtain reference values for body position and movement; and (3) the 24-hr monitoring. 21 patients could be recorded a second time, on average 18 days after the first recording. Between the two registrations, patients received individually tailored drug treatment supplemented with specific activating physiotherapy, ergotherapy measures, and individual psychotherapeutic counseling. Changes between first and second recording were evident for the three tremor variables, but significant only for the 24-hr ambulatory monitoring. The between and within-subjects correlations of the tremor variables were rather low except the correlations between occurrence and amplitude (between-subjects. 87; within-subjects. 67). Conditions of rest and postural tremor test showed a correlation with corresponding segments of the ambulatory monitoring of about. 50 for the tremor occurrence. The best prediction of the day-time monitoring was made by the tremor tests with distraction, whereas the night segment was best predicted by the standard protocol.


Asunto(s)
Microcomputadores , Monitoreo Ambulatorio/instrumentación , Enfermedad de Parkinson/diagnóstico , Procesamiento de Señales Asistido por Computador/instrumentación , Temblor/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Antiparkinsonianos/uso terapéutico , Nivel de Alerta/fisiología , Atención/fisiología , Ritmo Circadiano/fisiología , Terapia Combinada , Femenino , Lateralidad Funcional/fisiología , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Persona de Mediana Edad , Actividad Motora/fisiología , Terapia Ocupacional , Enfermedad de Parkinson/fisiopatología , Enfermedad de Parkinson/rehabilitación , Modalidades de Fisioterapia , Postura/fisiología , Psicoterapia , Valores de Referencia , Resultado del Tratamiento , Temblor/fisiopatología , Temblor/rehabilitación
18.
J Med Eng Technol ; 21(1): 15-22, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9080357

RESUMEN

Stroke volume estimates and left ventricular ejection time (1) derived from calibrated finger pulse pressure recordings (Portapres 2, TNO-BMI, Amsterdam) based on the Model Flow method and (2) derived from impedance cardiography were compared in 20 student subjects. The recordings were made for seven conditions: supine rest, standing, mental arithmetic, ergometer exercise 50 W, motor performance test, reading aloud, and walking. Findings indicated that caution is required in assuming concurrent validity for both methods in tracking haemodynamic changes. Within-subject correlations were low or even negligible. Basic discrepancies were evident regarding the estimation of left ventricular ejection time but obviously more sources of measurement error exist which necessitate further research.


Asunto(s)
Monitoreo Ambulatorio de la Presión Arterial/instrumentación , Monitoreo Ambulatorio de la Presión Arterial/normas , Cardiografía de Impedancia/normas , Volumen Sistólico , Adulto , Sesgo , Prueba de Esfuerzo , Humanos , Masculino , Postura , Reproducibilidad de los Resultados , Descanso
19.
Cell Death Dis ; 5: e1398, 2014 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-25165884

RESUMEN

Targeting the actin cytoskeleton (CSK) of cancer cells offers a valuable strategy in cancer therapy. There are a number of natural compounds that interfere with the actin CSK, but the mode of their cytotoxic action and, moreover, their tumor-specific mechanisms are quite elusive. We used the myxobacterial compound Chondramide as a tool to first elucidate the mechanisms of cytotoxicity of actin targeting in breast cancer cells (MCF7, MDA-MB-231). Chondramide inhibits cellular actin filament dynamics shown by a fluorescence-based analysis (fluorescence recovery after photobleaching (FRAP)) and leads to apoptosis characterized by phosphatidylserine exposure, release of cytochrome C from mitochondria and finally activation of caspases. Chondramide enhances the occurrence of mitochondrial permeability transition (MPT) by affecting known MPT modulators: Hexokinase II bound to the voltage-dependent anion channel (VDAC) translocated from the outer mitochondrial membrane to the cytosol and the proapoptotic protein Bad were recruited to the mitochondria. Importantly, protein kinase C-ɛ (PKCɛ), a prosurvival kinase possessing an actin-binding site and known to regulate the hexokinase/VDAC interaction as well as Bad phosphorylation was identified as the link between actin CSK and apoptosis induction. PKCɛ, which was found overexpressed in breast cancer cells, accumulated in actin bundles induced by Chondramide and lost its activity. Our second goal was to characterize the potential tumor-specific action of actin-binding agents. As the nontumor breast epithelial cell line MCF-10A in fact shows resistance to Chondramide-induced apoptosis and notably express low level of PKCɛ, we suggest that trapping PKCɛ via Chondramide-induced actin hyperpolymerization displays tumor cell specificity. Our work provides a link between targeting the ubiquitously occurring actin CSK and selective inhibition of pro-tumorigenic PKCɛ, thus setting the stage for actin-stabilizing agents as innovative cancer drugs. This is moreover supported by the in vivo efficacy of Chondramide triggered by abrogation of PKCɛ signaling shown in a xenograft breast cancer model.


Asunto(s)
Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Proteína Quinasa C/metabolismo , Citoesqueleto de Actina/efectos de los fármacos , Actinas/genética , Animales , Antineoplásicos/uso terapéutico , Antineoplásicos/toxicidad , Apoptosis/efectos de los fármacos , Sitios de Unión , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Citocromos c/metabolismo , Depsipéptidos/uso terapéutico , Depsipéptidos/toxicidad , Femenino , Recuperación de Fluorescencia tras Fotoblanqueo , Hexoquinasa/metabolismo , Humanos , Células MCF-7 , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones , Ratones SCID , Mitocondrias/metabolismo , Fosfatidilserinas/farmacología , Transducción de Señal , Trasplante Heterólogo , Canales Aniónicos Dependientes del Voltaje/metabolismo , Proteína Letal Asociada a bcl/metabolismo
20.
Behav Res Methods Instrum Comput ; 32(3): 450-7, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11029819

RESUMEN

Basic motion patterns and posture can be distinguished by multichannel accelerometry, as recently shown. A refinement of this method appeared to be desirable to further increase its effectiveness, especially to distinguish walking and climbing stairs, and body rotation during sleep. Recordings were made of 31 subjects, according to a standard protocol comprising 13 motions and postures. This recording was repeated three times with appropriate permutation. Five uni-axial sensors and three sites of placement (sternum with three axes, right and left thigh) were selected. A hierarchical classification strategy used a standard protocol (i.e., individual reference patterns) to distinguish subtypes of moving behaviors and posture. The analysis method of the actometer signals reliably detected 13 different postural and activity conditions (only 3.2% misclassifications). A minimum set of sensors can be found for a given application; for example, a two-sensor configuration would clearly suffice to differentiate between four basic classes (sitting, standing, lying, moving) in ambulatory monitoring.


Asunto(s)
Movimiento , Postura , Adulto , Conducta , Fenómenos Biomecánicos , Calibración , Equipos y Suministros , Humanos , Masculino
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