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1.
Sensors (Basel) ; 21(23)2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34884044

RESUMEN

Anemia is a condition in which red blood cells or the hemoglobin in the blood is lower than in healthy people. Red blood cells transport and supply oxygen needed to various organs in the human body. Anemia is caused by hypoxemia due to the lack of red blood cells and causes other serious health problems, such as heart problems, pregnancy complications, severe fatigue, or death. There are many causes of anemia, and it can be diagnosed by measuring hematocrit or hemoglobin levels in the blood. Even though there are various diagnostic devices on the market, these devices are inconvenient because their systems are bulky, heavy, expensive, or inaccurate. This study proposed a new anemia diagnostic system based on the impedance measurement of red blood cells. The proposed system consists of a test strip that collects a blood sample from the finger and a hemoglobin meter that measures the impedance of the blood and converts it into the concentration of hemoglobin. The proposed test strip that does not contain enzymes or reagents was designed in accordance with class 1 approval by the Food and Drug Administration (FDA). The hemoglobin meter was designed to include a hardware block, an algorithm block and a calibration block through empirical work. We also compared it to reference impedance to prove the accuracy of the hemoglobin meter. The experimental results with human blood indicated the superiority of the anemia diagnostic system. As a result, the overall standard deviation of impedance measurements was less than 1%, and the coefficient of variance of the proposed system was 1.7%, which was better than that of other commercial systems.


Asunto(s)
Anemia , Anemia/diagnóstico , Impedancia Eléctrica , Eritrocitos , Hematócrito , Hemoglobinas/análisis , Humanos
2.
Biomed Res Int ; 2021: 5521009, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34476259

RESUMEN

Loss of knee cartilage can cause intense pain at the knee epiphysis and this is one of the most common diseases worldwide. To diagnose this condition, the distance between the femur and tibia is calculated based on X-ray images. Accurate segmentation of the femur and tibia is required to assist in the calculation process. Several studies have investigated the use of automatic knee segmentation to assist in the calculation process, but the results are of limited value owing to the complexity of the knee. To address this problem, this study exploits deep learning for robust segmentation not affected by the environment. In addition, the Taguchi method is applied to optimize the deep learning results. Deep learning architecture, optimizer, and learning rate are considered for the Taguchi table to check the impact and interaction of the results. When the Dilated-Resnet architecture is used with the Adam optimizer and a learning rate of 0.001, dice coefficients of 0.964 and 0.942 are obtained for the femur and tibia for knee segmentation. The implemented procedure and the results of this investigation may be beneficial to help in determining the correct margins for the femur and tibia and can be the basis for developing an automatic diagnosis algorithm for orthopedic diseases.


Asunto(s)
Fémur/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Articulación de la Rodilla/diagnóstico por imagen , Rodilla/patología , Osteoartritis de la Rodilla/diagnóstico por imagen , Tibia/diagnóstico por imagen , Fémur/patología , Humanos , Rodilla/diagnóstico por imagen , Articulación de la Rodilla/patología , Redes Neurales de la Computación , Osteoartritis de la Rodilla/patología , Tibia/patología , Rayos X
3.
Korean J Radiol ; 14(2): 321-3, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23482853

RESUMEN

Most intrasellar meningiomas are located in the subdiaphragmatic and supraglandular region because they originate from the diaphragma sellae. Subglandular meningiomas located under the pituitary gland are extremely rare. Intrasellar meningiomas in the subdiaphragmatic and subglandular region probably originate from the dura in the sellar floor. We report a case of a subglandular meningioma along with a review of the literature.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Meningioma/diagnóstico , Neoplasias Hipofisarias/diagnóstico , Silla Turca/patología , Diagnóstico Diferencial , Femenino , Humanos , Meningioma/patología , Meningioma/cirugía , Persona de Mediana Edad , Neoplasias Hipofisarias/patología , Neoplasias Hipofisarias/cirugía
4.
Korean J Radiol ; 10(5): 511-4, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19721837

RESUMEN

We report a case of hypereosinophilia causing multiple areas of cerebral infarcts. A 52-year-old Korean man presented with dysarthria and weakness in both arms. A brain MRI revealed multiple acute infarcts in the distal border zone with focal intracerebral hemorrhage, whereas a cerebral angiogram was not remarkable. The eosinophil count was 5,500/microL and was accompanied by elevated cardiac enzyme levels. The pattern of cerebral infarcts and laboratory results suggest a thromboembolic infarction associated with hypereosinophilia.


Asunto(s)
Hemorragia Cerebral/etiología , Infarto Cerebral/etiología , Eosinofilia/complicaciones , Hemorragia Cerebral/diagnóstico , Infarto Cerebral/diagnóstico , Diagnóstico Diferencial , Eosinofilia/tratamiento farmacológico , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad
5.
Biosens Bioelectron ; 24(7): 1877-82, 2009 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-18977651

RESUMEN

A highly sensitive penicillin biosensor based on a charge-transfer technique (CTTPS) has been fabricated and demonstrated in this paper. CTTPS comprised a charge accumulation technique for penicilloic acid and H(+) ions perception system. With the proposed CTTPS, it is possible to amplify the sensing signals without external amplifier by using the charge accumulation cycles. The fabricated CTTPS exhibits excellent performance for penicillin detection and exhibit a high-sensitivity (47.852 mV/mM), high signal-to-noise ratio (SNR), large span (1445 mV), wide linear range (0-25 mM), fast response time (<3s), and very good reproducibility. A very lower detection limit of about 0.01 mM was observed from the proposed sensor. Under optimum conditions, the proposed CTTPS outstripped the performance of the widely used ISFET penicillin sensor and exhibited almost eight times greater sensitivity as compared to ISFET (6.56 mV/mM). The sensor system is implemented for the measurement of the penicillin concentration in penicillin fermentation broth.


Asunto(s)
Técnicas Biosensibles/instrumentación , Electroquímica/instrumentación , Electroquímica/métodos , Oxidorreductasas/química , Penicilinas/análisis , Enzimas Inmovilizadas/química , Diseño de Equipo , Análisis de Falla de Equipo , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Electricidad Estática
6.
Biosens Bioelectron ; 24(4): 650-6, 2008 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-18640027

RESUMEN

An enhanced glucose biosensor based on a charge transfer technique glucose sensor (CTTGS) is described and demonstrated experimentally. In the proposed CTTGS, which is accumulation method (d-gluconate+H(+)) ion perception system, the quality of output signal with "signal integration cycles" is high. With the proposed CTTGS it is possible to amplify the sensing signals without an external amplifier by using an accumulation cycle. It can be supposed that measurements of small (d-gluconate+H(+)) ion fluctuation are difficult by ion-sensitive field effect transistor (ISFET) because the theoretical maximum sensitivity is only 59 mV/pH and the small output signals are buried in the 1/f noise component of the metal-insulator-semi-conductor field-effect transistor (MISFET). Therefore, the CTTGS has many advantages, such as high sensitivity, high accuracy, high signal-to-noise ratio (SNR), and has been successfully demonstrated using a charge transfer technique. The CTTGS exhibited excellent performance for glucose with a large span (1445 mV) and good reproducibility. Moreover, the CTTGS has good sensitivity in this range of 7.22mV/mM, a lower detection limit of about 0.01 mM/L and an upper detection limit of about 200 mM/L compared with amperometric glucose analysis which has been studied recently. Under optimum conditions, the proposed CTTGS exceeds the performance of the widely used ISFET glucose sensor. The sensitivity of the CTTGS (7.22 mV/mM) was seven times higher than that of the ISFET (1 mV/mM). Furthermore, the sensitivity obtained for human glucose levels was 29.06 mV/mM with a non-linear error of +/-0.27%; the linearity is y=0.0294x+1.8612 and R(2)=0.9999, which is acceptable for clinical application. Real sample analysis is investigated in blood glucose level by our developed CTTGS ISFET system.


Asunto(s)
Técnicas Biosensibles/instrumentación , Electroquímica/instrumentación , Glucosa Oxidasa/química , Glucosa/análisis , Transistores Electrónicos , Técnicas Biosensibles/métodos , Enzimas Inmovilizadas/química , Diseño de Equipo , Análisis de Falla de Equipo , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Electricidad Estática
7.
Biosens Bioelectron ; 24(3): 410-4, 2008 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-18524563

RESUMEN

This paper presents a glucose biosensor, which was developed using a Au/Ni/copper electrode. Until now, research regarding the low electrical resistance and uniformity of this biosensor electrode has not been conducted. Glucose oxidase (GOD) immobilized on the electrode effectively plays the role of an electron shuttle, and allows glucose to be detected at 0.055 V with a dramatically reduced resistance to easily oxidizable constituents. The Au/Ni/copper electrode has a low electrical resistance, which is less than 0.01 Omega, and it may be possible to mass produce the biosensor electrode with a uniform electrical resistance. The low electrical resistance has the advantage in that the redox peak occurs at a low applied potential. Using a low operating potential (0.055 V), the GOD/Au/Ni/copper structure creates a good sensitivity to detect glucose, and efficiently excludes interferences from common coexisting substances. The GOD/Au/Ni/copper sensor exhibits a relatively short response time (about 3s), and a sensitivity of 0.85 microA mM(-1) with a linear range of buffer to 33 mM of glucose. The sensor has excellent reproducibility with a correlation coefficient of 0.9989 (n=100 times) and a total non-linearity error of 3.17%.


Asunto(s)
Técnicas Biosensibles/instrumentación , Electrodos , Glucosa Oxidasa/química , Glucosa/análisis , Técnicas Biosensibles/métodos , Cobre/química , Electroquímica , Oro/química , Níquel/química , Reproducibilidad de los Resultados
8.
J Clin Neurosci ; 12(6): 699-702, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16115554

RESUMEN

A 34-year old man with a past history of hepatocellular carcinoma (HCC) complained of headache and visual disturbance. Neuroimaging revealed a right occipital haematoma with rim enhancement and at operation, a metastasis from the primary malignancy was found. Five months after surgery and subsequent adjuvant therapy, he presented with blindness. On neuroimaging, a left occipital haematoma was seen. The patient refused surgical intervention. HCC usually has an aggressive clinical course; therefore, recurrent cerebral metastasis is an uncommon clinical problem. "Mirror-image" metastasis, with bleeding in both hemispheres, is rare and has not been reported. We suggest that these metastases occur due to microscopic seeding via an arterial route, and that spread via a venous route, such as occurs through Batson's plexus, is unlikely.


Asunto(s)
Neoplasias Encefálicas/complicaciones , Carcinoma Hepatocelular/complicaciones , Hemorragia Cerebral/complicaciones , Neoplasias Hepáticas/complicaciones , Adulto , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/cirugía , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/cirugía , Humanos , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/cirugía , Imagen por Resonancia Magnética/métodos , Masculino , Recurrencia , Tomografía Computarizada por Rayos X/métodos
9.
Eur J Neurosci ; 20(6): 1461-72, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15355313

RESUMEN

Poly(ADP-ribose) polymerase (PARP) plays an important role in ischaemic cell death, and 3-aminobenzamide (3-AB), one of the PARP inhibitors, has a protective effect on ischaemic stroke. We investigated the neuroprotective mechanisms of 3-AB in ischaemic stroke. The occlusion of middle cerebral artery (MCA) was made in 170 Sprague-Dawley rats, and reperfusion was performed 2 h after the occlusion. Another 10 Sprague-Dawley rats were used for sham operation. 3-AB was administered to 85 rats 10 min before the occlusion [3-AB group (n = 85) vs. control group without 3-AB (n = 85)]. Infarct volume and water content were measured, brain magnetic resonance imaging, terminal deoxynucleotidyltransferase (TdT)-mediated dUTP-biotin nick end-labelling (TUNEL) and Cresyl violet staining were performed, and immunoreactivities (IRs) of poly(ADP-ribose) polymer (PAR), cleaved caspase-3, CD11b, intercellular adhesion molecule-1 (ICAM-1), cyclooxygenase-2 (COX-2), phospho-Akt (pAkt) and phospho-glycogen synthase kinase-3 (pGSK-3) were compared in the peri-infarcted region of the 3-AB group and its corresponding ischaemic region of the control group at 2, 8, 24 and 72 h after the occlusion. In the 3-AB group, the infarct volume and the water content were decreased (about 45% and 3.6%, respectively, at 24 h), the number of TUNEL-positive cells was decreased (about 36% at 24 h), and the IRs of PAR, cleaved caspase-3, CD11b, ICAM-1 and COX-2 were significantly reduced, while the IRs of pAkt and pGSK-3 were increased. These results suggest that 3-AB treatment could reduce the infarct volume by reducing ischaemic cell death, its related inflammation and increasing survival signals. The inhibition of PARP could be another potential neuroprotective strategy in ischaemic stroke.


Asunto(s)
Benzamidas/farmacología , Isquemia Encefálica/patología , Muerte Celular , Epoprostenol/análogos & derivados , Fármacos Neuroprotectores/farmacología , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Animales , Benzamidas/uso terapéutico , Western Blotting/métodos , Encéfalo/metabolismo , Encéfalo/patología , Edema Encefálico/etiología , Edema Encefálico/patología , Edema Encefálico/prevención & control , Infarto Encefálico/etiología , Infarto Encefálico/patología , Infarto Encefálico/prevención & control , Isquemia Encefálica/etiología , Isquemia Encefálica/metabolismo , Antígeno CD11b/metabolismo , Caspasa 3 , Caspasas/metabolismo , Recuento de Células/métodos , Muerte Celular/efectos de los fármacos , Ciclooxigenasa 2 , Femenino , Lateralidad Funcional/fisiología , Glucógeno Sintasa Quinasa 3/metabolismo , Inmunohistoquímica/métodos , Etiquetado Corte-Fin in Situ , Infarto de la Arteria Cerebral Media/complicaciones , Inflamación/etiología , Inflamación/prevención & control , Molécula 1 de Adhesión Intercelular/metabolismo , Isoenzimas/metabolismo , Imagen por Resonancia Magnética/métodos , Masculino , Fármacos Neuroprotectores/uso terapéutico , Poli(ADP-Ribosa) Polimerasas/metabolismo , Prostaglandina-Endoperóxido Sintasas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-akt , Ratas , Ratas Sprague-Dawley , Coloración y Etiquetado , Factores de Tiempo
10.
J Neurooncol ; 67(1-2): 107-13, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15072455

RESUMEN

We report a rare case of skull metastasis from ampulla of Vater adenocarcinoma in a patient with controlled primary neoplasm. This 65-year-old Korean man presented with headache and painful parietal scalp swelling, but he did not show any neurological deficits. Computed tomography revealed an osteolytic mass that invaded and expanded through the skull tables in full-thickness. On magnetic resonance images following Gadolinium injection, the mass appeared slightly hypointense signal on all sequences and intense heterogeneous enhancement. He underwent surgical excision with artificial grafting of calvaria and dura. Postoperative radiation therapy was ensued for metastatic adenocarcinoma, and he was well for the follow-up period of 3 months. To the best of our knowledge, this is the first such case that involved the skull.


Asunto(s)
Adenocarcinoma/secundario , Ampolla Hepatopancreática/patología , Neoplasias del Conducto Colédoco/patología , Neoplasias Craneales/secundario , Adenocarcinoma/fisiopatología , Adenocarcinoma/terapia , Anciano , Neoplasias del Conducto Colédoco/fisiopatología , Neoplasias del Conducto Colédoco/terapia , Humanos , Imagen por Resonancia Magnética , Masculino , Neoplasias Craneales/fisiopatología , Neoplasias Craneales/terapia , Tomografía Computarizada por Rayos X
11.
AJNR Am J Neuroradiol ; 25(4): 631-5, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15090357

RESUMEN

Basal cell adenoma is a rare benign salivary gland epithelial tumor, usually involving the parotid gland. We report CT and MR findings of three cases with basal cell adenoma occurring in the parotid gland. The three cases presented here demonstrate a well-circumscribed tumor, which showed a cystic and solid, or the pure solid mass. They were well enhanced after contrast matter injection. The solid portion of the mass was isoattenuated at CT, with intermediate signal intensity on T1- and T2-weighted MR images. Its cystic portion was hyperintense on both T1- and T2-weighted MR images. It had a hypointense rim on T2-weighted image.


Asunto(s)
Adenoma/diagnóstico , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Neoplasias de la Parótida/diagnóstico , Tomografía Computarizada por Rayos X , Adenoma/patología , Adenoma/cirugía , Biopsia con Aguja , Diagnóstico Diferencial , Femenino , Humanos , Persona de Mediana Edad , Glándula Parótida/patología , Glándula Parótida/cirugía , Neoplasias de la Parótida/patología , Neoplasias de la Parótida/cirugía
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