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1.
IEEE J Biomed Health Inform ; 22(3): 835-841, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-28541917

RESUMEN

Unilateral peripheral facial paralysis (UPFP) is a form of facial nerve paralysis and clinically classified according to conditions of facial symmetry. Prompt and precise assessment is crucial to neural rehabilitation of UPFP. The prevalent House-Brackmann (HB) grading system relies on subjective judgments with significant interobservation variation. Therefore, to explore an objective method for the UPFP assessment, clinical image sequences are captured using a web camera setup while 5 healthy and 27 UPFP subjects perform a group of predefined actions, including keeping expressionless, raising brows, closing eyes, bulging cheek, and showing teeth in turn. First, facial region is decided using Haar cascade classifier, and then landmark points are acquired by a supervised descent method. Second, these landmark points are used to generate a group of features reflecting the structural parameters of regions of eyebrows, eyes, nose, and mouth, respectively. Third, correlation coefficients are computed between the raw features HB scores. To reduce feature dimensions, only those with correlation coefficients larger than an empirically selected value, 0.35, are input into a support vector machine to generate a classifier. With the classifier, exact match (discrepancy = 0 between result from proposed method and HB scores) rate at 49.9%, and loose match (discrepancy = 1) rate at 87.97% are achieved on the experiment data. After sample augmentation, the final rate is increased to 90.01%, outperformed previous reports. In conclusion, it is demonstrated with an unobtrusive web camera setup, encouraging results have been generated with the proposed framework in this exploratory study.


Asunto(s)
Parálisis Facial/diagnóstico por imagen , Parálisis Facial/fisiopatología , Interpretación de Imagen Asistida por Computador/métodos , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fotograbar , Máquina de Vectores de Soporte , Adulto Joven
2.
Ultrasound Med Biol ; 42(7): 1499-511, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27126236

RESUMEN

Imaging or therapeutic agents larger than the blood-brain barrier's (BBB) exclusion threshold of 400 Da could be delivered locally, non-invasively and reversibly by focused ultrasound (FUS) with circulating microbubbles. The size of agents is an important factor to the delivery outcome using this method. Liposomes are important drug carriers with controllable sizes in a range of nanometers. However, discrepancies among deliveries of intact liposomes with different sizes, especially those larger than 50 nm, across the BBB opened by FUS with microbubbles remain unexplored. In the present study, rhodamine-labeled long-circulating pegylated liposomes with diameters of 55 nm, 120 nm and 200 nm were delivered to mice brains after BBB disruption by pulsed FUS with microbubbles. Four groups of peak rarefactional pressure and microbubble dosages were used: 0.53 MPa with 0.1 µL/g (group 1), 0.53 MPa with 0.5 µL/g (group 2), 0.64 MPa with 0.1 µL/g (group 3) and 0.64 MPa with 0.5 µL/g (group 4). The delivery outcome was observed using fluorescence imaging of brain sections. It was found that the delivery of 55-nm liposomes showed higher success rates than 120-nm or 200-nm liposomes from groups 1-3. The result indicated that it may be more difficult to deliver larger liposomes (>120 nm) passively than 55-nm liposomes after BBB opening by FUS with microbubbles. The relative fluorescence area of 55-nm liposomes to the total area of the sonicated region was statistically larger than that of the 120-nm or 200-nm liposomes. Increasing peak rarefactional pressure amplitude or microbubble dose could induce more accumulation of liposomes in the brain using FUS with microbubbles. Moreover, the distribution pattern of delivered liposomes was heterogeneous and characterized by separated fluorescence spots with cloud-like periphery surrounding a bright center, indicating confined diffusion in the extracellular matrix after extravasation from the microvasculature. These findings are expected to provide useful information for developing FUS with microbubbles as an effective trans-BBB liposomal drug delivery strategy.


Asunto(s)
Encéfalo/metabolismo , Sistemas de Liberación de Medicamentos/métodos , Liposomas/administración & dosificación , Ondas Ultrasónicas , Animales , Barrera Hematoencefálica , Permeabilidad Capilar , Femenino , Ratones , Ratones Endogámicos BALB C , Microburbujas , Modelos Animales
3.
Regul Toxicol Pharmacol ; 46(3): 211-7, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17010489

RESUMEN

Polybutylcyanoacrylate nanoparticles (PBCA-NP) were prepared by addition of the monomer to an aqueous phase containing dextran 70 and loaded with mitomycin C (MMC-PBCA-NP), a highly effective anticancer drug. When injected into mice, MMC-PBCA-NP accumulated more in the liver than did free MMC. In contrast, MMC-PBCA-NP accumulated less in the heart and kidney than did free MMC. However, when MMC-PBCA-NP and MMC were administered to rabbits bearing VX2 cells implanted into the liver, the antiproliferative effects on the tumor cells of both drugs were similar. Histological analyses indicated that organization of myocardial filaments was disrupted and vacuolization was observed in the MMC treated group, whereas MMC-PBCA-NP treatment did not appear to damage the host's heart. Hydropic degeneration of renal tubular epithelia was observed in the MMC treated group and not in the control group, whereas MMC-PBCA-NP treatment did not appear to damage the host's kidney.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Portadores de Fármacos/administración & dosificación , Enbucrilato/administración & dosificación , Neoplasias Hepáticas/tratamiento farmacológico , Mitomicina/administración & dosificación , Nanopartículas , Animales , Antibióticos Antineoplásicos/farmacocinética , Línea Celular Tumoral , Portadores de Fármacos/farmacocinética , Enbucrilato/farmacocinética , Femenino , Corazón/efectos de los fármacos , Inyecciones Intravenosas , Riñón/efectos de los fármacos , Riñón/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Neoplasias Hepáticas/metabolismo , Ratones , Mitomicina/farmacocinética , Miocardio/metabolismo , Conejos , Bazo/efectos de los fármacos , Distribución Tisular
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