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1.
Biosensors (Basel) ; 14(4)2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38667181

RESUMEN

Carbon nanotube (CNT)-based nanocomposites have found applications in making sensors for various types of physiological sensing. However, the sensors' fabrication process is usually complex, multistep, and requires longtime mixing and hazardous solvents that can be harmful to the environment. Here, we report a flexible dry silver (Ag)/CNT/polydimethylsiloxane (PDMS) nanocomposite-based sensor made by a solvent-free, low-temperature, time-effective, and simple approach for electrophysiological recording. By mechanical compression and thermal treatment of Ag/CNT, a connected conductive network of the fillers was formed, after which the PDMS was added as a polymer matrix. The CNTs make a continuous network for electrons transport, endowing the nanocomposite with high electrical conductivity, mechanical strength, and durability. This process is solvent-free and does not require a high temperature or complex mixing procedure. The sensor shows high flexibility and good conductivity. High-quality electroencephalography (EEG) and electrooculography (EOG) were performed using fabricated dry sensors. Our results show that the Ag/CNT/PDMS sensor has comparable skin-sensor interface impedance with commercial Ag/AgCl-coated dry electrodes, better performance for noninvasive electrophysiological signal recording, and a higher signal-to-noise ratio (SNR) even after 8 months of storage. The SNR of electrophysiological signal recording was measured to be 26.83 dB for our developed sensors versus 25.23 dB for commercial Ag/AgCl-coated dry electrodes. Our process of compress-heating the functional fillers provides a universal approach to fabricate various types of nanocomposites with different nanofillers and desired electrical and mechanical properties.


Asunto(s)
Dimetilpolisiloxanos , Nanocompuestos , Nanotubos de Carbono , Plata , Nanocompuestos/química , Nanotubos de Carbono/química , Plata/química , Dimetilpolisiloxanos/química , Electroencefalografía , Conductividad Eléctrica , Técnicas Biosensibles , Humanos , Electrooculografía , Electrodos , Relación Señal-Ruido
2.
Cancers (Basel) ; 13(2)2021 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-33430396

RESUMEN

PURPOSE: Chemo-radiotherapy (CRT) is the standard treatment for non-metastatic anal squamous cell carcinomas (ASCC). Despite excellent results for T1-2 stages, relapses still occur in around 35% of locally advanced tumors. Recent strategies focus on treatment intensification, but could benefit from a better patient selection. Our goal was to assess the prognostic value of pre-therapeutic MRI radiomics on 2-year disease control (DC). METHODS: We retrospectively selected patients with non-metastatic ASCC treated at the CHU Bordeaux and in the French FFCD0904 multicentric trial. Radiomic features were extracted from T2-weighted pre-therapeutic MRI delineated sequences. After random division between training and testing sets on a 2:1 ratio, univariate and multivariate analysis were performed on the training cohort to select optimal features. The correlation with 2-year DC was assessed using logistic regression models, with AUC and accuracy as performance gauges, and the prediction of disease-free survival using Cox regression and Kaplan-Meier analysis. RESULTS: A total of 82 patients were randomized in the training (n = 54) and testing sets (n = 28). At 2 years, 24 patients (29%) presented relapse. In the training set, two clinical (tumor size and CRT length) and two radiomic features (FirstOrder_Entropy and GLCM_JointEnergy) were associated with disease control in univariate analysis and included in the model. The clinical model was outperformed by the mixed (clinical and radiomic) model in both the training (AUC 0.758 versus 0.825, accuracy of 75.9% versus 87%) and testing (AUC 0.714 versus 0.898, accuracy of 78.6% versus 85.7%) sets, which led to distinctive high and low risk of disease relapse groups (HR 8.60, p = 0.005). CONCLUSION: A mixed model with two clinical and two radiomic features was predictive of 2-year disease control after CRT and could contribute to identify high risk patients amenable to treatment intensification with view of personalized medicine.

3.
J Cereb Blood Flow Metab ; 34(4): 638-45, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24447951

RESUMEN

Contrast-enhanced radiotherapy is an innovative treatment that combines the selective accumulation of heavy elements in tumors with stereotactic irradiations using medium energy X-rays. The radiation dose enhancement depends on the absolute amount of iodine reached in the tumor and its time course. Quantitative, postinfusion iodine biodistribution and associated brain perfusion parameters were studied in human brain metastasis as key parameters for treatment feasibility and quality. Twelve patients received an intravenous bolus of iodinated contrast agent (CA) (40 mL, 4 mL/s), followed by a steady-state infusion (160 mL, 0.5 mL/s) to ensure stable intratumoral amounts of iodine during the treatment. Absolute iodine concentrations and quantitative perfusion maps were derived from 40 multislice dynamic computed tomography (CT) images of the brain. The postinfusion mean intratumoral iodine concentration (over 30 minutes) reached 1.94 ± 0.12 mg/mL. Reasonable correlations were obtained between these concentrations and the permeability surface area product and the cerebral blood volume. To our knowledge, this is the first quantitative study of CA biodistribution versus time in brain metastasis. The study shows that suitable and stable amounts of iodine can be reached for contrast-enhanced radiotherapy. Moreover, the associated perfusion measurements provide useful information for the patient recruitment and management processes.


Asunto(s)
Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundario , Circulación Cerebrovascular/fisiología , Medios de Contraste , Yopamidol/análogos & derivados , Imagen de Perfusión/métodos , Volumen Sanguíneo/fisiología , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/fisiopatología , Medios de Contraste/administración & dosificación , Medios de Contraste/farmacocinética , Humanos , Infusiones Intravenosas , Inyecciones Intravenosas , Yopamidol/administración & dosificación , Yopamidol/farmacocinética , Estudios Prospectivos , Dosificación Radioterapéutica , Sincrotrones , Factores de Tiempo , Distribución Tisular , Tomografía Computarizada por Rayos X
4.
J Eval Clin Pract ; 18(4): 911-8, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21689216

RESUMEN

RATIONALE, AIMS AND OBJECTIVES: To analyse pharmacists' interventions in a setting where a computerized physician order entry system (CPOE) is in use and a pharmacist works on the ward. METHOD: A prospective cohort study was conducted in seven wards of a French teaching hospital using CPOE along with the presence of a full-time on-ward pharmacy resident. We documented the characteristics of pharmacists' interventions communicated to physicians during the medication order validation process whenever a drug-related problem was identified. Independent predictors of the physician's acceptance of the pharmacist's intervention were assessed using multiple logistic regression analysis. RESULTS: The 448 pharmacists' interventions concerned: non-conformity to guidelines or contraindications (22%), too high doses (19%), drug interactions (15%) and improper administration (15%). The interventions consisted of changes in drug choice (41%), dose adjustment (23%), drug monitoring (19%) and optimization of administration (17%). Interventions were communicated via the CPOE in 57% of cases and 43% orally. The rate of physicians' acceptance was 79.2%. In multivariate analysis, acceptance was significantly associated with the physician's status [higher for residents vs. seniors: OR = 7.23, CI 95 (2.37-22.10), P < 0.01], method of communication [higher for oral vs. computer communication: OR = 12.5, CI 95 (4.16-37.57), P < 0.01] and type of recommendation [higher for drug monitoring vs. drug choice recommendations: OR = 10.32, CI 95 (3.20-33.29), P < 0.01]. CONCLUSIONS: When a clinical pharmacist is present on a ward in which a CPOE is in use, the pharmacists' interventions are well accepted by physicians. Specific predictors of the acceptance by physicians emerge, but further research as to the impact of CPOE on pharmacist-physician communication is needed.


Asunto(s)
Comunicación Interdisciplinaria , Sistemas de Entrada de Órdenes Médicas , Farmacéuticos , Rol Profesional , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Intervalos de Confianza , Femenino , Francia , Hospitales Universitarios , Humanos , Masculino , Errores de Medicación/prevención & control , Persona de Mediana Edad , Seguridad del Paciente , Servicio de Farmacia en Hospital , Estudios Prospectivos , Adulto Joven
5.
Therapie ; 60(5): 515-22, 2005.
Artículo en Francés | MEDLINE | ID: mdl-16433018

RESUMEN

BACKGROUND: Computerised physician order entry (CPOE) and the integration of a pharmacist in clinical wards have been shown to prevent medication errors. OBJECTIVES: The objectives were to describe interventions performed by a clinical pharmacist integrated into clinical wards with CPOE, to assess the acceptance of interventions by prescribers, and to describe factors associated with acceptance. METHODS: A 3-week prospective study was conducted in five wards of a 2000-bed French teaching hospital. RESULTS: During pharmacist review of medication orders and participation on physician rounds, six resident pharmacists provided interventions either conveyed orally to prescribers, using the computer system, or combining both methods. There were 221 pharmacist interventions concerning drug-drug interactions (27%), drug monitoring (17%) and computer-related problems (16%). Pharmacist interventions consisted of change of drug choice or dose adjustment (49%), drug monitoring (17%) and administration modality optimisation (14%). Interventions were provided solely via computer systems in 67% of cases. The rate of intervention acceptance was 47.1%. In multivariate analysis, acceptance was significantly associated with oral transmission (odds ratio [OR] = 6.46; 95% confidence interval [95% CI] [1.65-25.24]; p < 0.01), change of drug choice or dose adjustment recommendations (OR = 3.81; 95% CI [1.63-8.86]; p < 0.01) and administration modality optimisation recommendations (OR = 9.51; 95% CI [3.02-29.93]; p < 0.01). CONCLUSION: Communication method and nature of recommendation are factors associated with pharmacist intervention acceptance. CPOE is necessary to develop clinical pharmacy practice. However, only the integration of the pharmacist on the ward can guarantee a high level of acceptance of pharmacist interventions by prescribers.


Asunto(s)
Pacientes Internos , Errores Médicos/prevención & control , Habitaciones de Pacientes , Servicio de Farmacia en Hospital/estadística & datos numéricos , Francia , Hospitales con más de 500 Camas , Hospitales de Enseñanza , Humanos , Servicio de Farmacia en Hospital/normas
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