Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
1.
Adv Mater ; 36(4): e2309028, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37991324

RESUMEN

Quantum dot photodiodes (QPDs) have garnered significant attention because of their unparalleled near-infrared (NIR) detection capabilities, primarily attributable to their size-dependent bandgap tunability. Nevertheless, the broadband absorption spectrum of QPD engenders substantial noise floor within superfluous visible light regions, notably hindering their use in several emerging applications necessitating the detection of faint micro-light signals. To overcome these hurdles, a self-screenable NIR QPD featuring an internal optical filter with a thick polymeric interlayer to reduce electronic noise is demonstrated. This effectively screens out undesirable visible light regions while reducing the ionized defect owing to decreased density of state, yielding an extremely low dark current (≈1010 A cm-2 at V = -1 V). Consequently, the electronic noise spectral density is attained at levels below ≈10-27 -10-28 A2 Hz-1 , and responsivity (R) dropped to 92% within the visible light spectrum.

2.
Adv Mater ; : e2403647, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38708960

RESUMEN

The near-infrared (NIR) sensor technology is crucial for various applications such as autonomous driving and biometric tracking. Silicon photodetectors (SiPDs) are widely used in NIR applications; however, their scalability is limited by their crystalline properties. Organic photodetectors (OPDs) have attracted attention for NIR applications owing to their scalability, low-temperature processing, and notably low dark current density (JD), which is similar to that of SiPDs. However, the still high JD (at NIR band) and few measurements of noise equivalent powers (NEPs) pose challenges for accurate performance comparisons. This study addresses these issues by quantitatively characterizing the performance matrix and JD generation mechanism using electron-blocking layers (EBLs) in OPDs. The energy offset at an EBL/photosensitive layer interface determines the thermal activation energy and directly affects JD. A newly synthesized EBL (3PAFBr) substantially enhances the interfacial energy barrier by forming a homogeneous contact owing to the improved anchoring ability of 3PAFBr. As a result, the OPD with 3PAFBr yields a noise current of 852 aA (JD = 12.3 fA cm⁻2 at V → -0.1 V) and several femtowatt-scale NEPs. As far as it is known, this is an ultralow of JD in NIR OPDs. This emphasizes the necessity for quantitative performance characterization.

3.
Gut Liver ; 17(6): 949-953, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36700301

RESUMEN

Gastric wall abscess is a rare condition characterized by a purulent inflammatory process resulting in the formation of a pocket of pus in the stomach. As the mucosa is usually intact, it requires various tools such as endoscopic ultrasonography or computed tomography for the differential diagnosis to rule out more common subepithelial tumors. Even after the diagnosis, the treatment for gastric wall abscess was previously restricted to surgical resection in combination with antibiotics. Currently, in order to avoid unnecessary surgery, the alternative method of initial treatment with an endoscopic approach is recommended. It also helps to choose appropriate antibiotics with confirmation of the pathogen by drainage. There are few reports that describe the detailed processing of the endoscopic drainage, and there is no consensus on the treatment. The pathogens that cause gastric wall abscess are usually Streptococci, Staphylococci, and Escherichia coli. There is only one case reported to be caused by Candida albicans. This is the first report of Elizabethkingia anopheles as the pathogen of the gastric wall abscess. Here, we report a case of gastric wall abscess in a 75-year-old man, safely treated by endoscopic drainage and antibiotics, confirmed by isolating the contents of the abscess.


Asunto(s)
Absceso , Enfermedades Raras , Masculino , Humanos , Anciano , Absceso/diagnóstico , Absceso/cirugía , Enfermedades Raras/tratamiento farmacológico , Enfermedades Raras/patología , Estómago/cirugía , Drenaje/métodos , Antibacterianos/uso terapéutico
4.
Korean J Radiol ; 8(3): 216-24, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17554189

RESUMEN

OBJECTIVE: We wanted to investigate the feasibility of using FDG-PET for evaluating the antitumor effect of intraarterial administration of a hexokinase II inhibitor, 3-bromopyruvate (3-BrPA), in a rabbit VX2 liver tumor model. MATERIALS AND METHODS: VX2 carcinoma was grown in the livers of ten rabbits. Two weeks later, liver CT was performed to confirm appropriate tumor growth for the experiment. After tumor volume-matched grouping of the rabbits, transcatheter intraarterial administration of 3-BrPA was performed (1 mM and 5 mM in five animals each, respectively). FDG-PET scan was performed the day before, immediately after and a week after 3-BrPA administration. FDG uptake was semiquantified by measuring the standardized uptake value (SUV). A week after treatment, the experimental animals were sacrificed and the necrosis rates of the tumors were calculated based on the histopathology. RESULTS: The SUV of the VX2 tumors before treatment (3.87+/-1.51 [mean+/-SD]) was significantly higher than that of nontumorous liver parenchyma (1.72+/-0.34) (p < 0.0001, Mann-Whitney U test). The SUV was significantly decreased immediately after 3-BrPA administration (2.05+/-1.21) (p = 0.002, Wilcoxon signed rank test). On the one-week follow up PET scan, the FDG uptake remained significantly lower (SUV 1.41+/-0.73) than that before treatment (p = 0.002), although three out of ten animals showed a slightly increasing tendency for the FDG uptake. The tumor necrosis rate ranged from 50.00% to 99.90% (85.48%+/-15.87). There was no significant correlation between the SUV or the SUV decrease rate and the tumor necrosis rate in that range. CONCLUSION: Even though FDG-PET cannot exactly reflect the tumor necrosis rate, FDG-PET is a useful modality for the early assessment of the antitumor effect of intraarterial administration of 3-BrPA in VX2 liver tumor.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Neoplasias Hepáticas Experimentales/diagnóstico por imagen , Neoplasias Hepáticas Experimentales/tratamiento farmacológico , Tomografía de Emisión de Positrones , Piruvatos/farmacología , Animales , Modelos Animales de Enfermedad , Estudios de Factibilidad , Fluorodesoxiglucosa F18 , Infusiones Intraarteriales , Inyecciones Intraarteriales , Neoplasias Hepáticas Experimentales/patología , Necrosis , Complejo Piruvato Deshidrogenasa/antagonistas & inhibidores , Conejos , Radiofármacos
5.
PLoS One ; 9(3): e90862, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24595361

RESUMEN

Insulin like-growth factor-1 (IGF-1) reflects hepatic synthetic function and plays a major role in the development and progression of various cancers. In the present study, we investigated whether baseline serum IGF-1 levels predict time-to-progression (TTP) and overall survival (OS) in hepatocellular carcinoma (HCC) patients treated with transarterial chemoembolization (TACE). A total of 155 consecutive treatment-naive patients with HCC who had undergone TACE as initial treatment were included from a prospective cohort. Baseline serum IGF-1 levels were analyzed with regard to their associations with disease progression and survival. During a median follow-up period of 41.8 months, patients with low IGF-1 levels showed significantly shorter TTP (median, 6.0 months; 95% confidence interval [CI], 4.5-7.6) than patients with high IGF-1 levels (median, 16.5 months; 95% CI, 4.9-28.1; p = 0.003). In the multivariate analysis, BCLC stage, serum vascular endothelial growth factorlevels, and IGF-1 levels were independent risk factors for disease progression. The hazard ratio (HR) of progression for each 10 ng/mL decrease in IGF-1 level was 1.072 (95% CI, 1.029-1.117; p = 0.001). Furthermore, together with tumor size, stage, and treatment response, IGF-1 levels were an independent predictor of poorer survival (for each 10 ng/mL decrease in IGF-1 level; HR, 1.057; 95% CI, 1.001-1.115; p = 0.045). In conclusion, low baseline IGF-1 levels independently correlated with shorter TTP and poorer OS in patients with HCC who underwent TACE.


Asunto(s)
Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/terapia , Factor I del Crecimiento Similar a la Insulina/análisis , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/terapia , Carcinoma Hepatocelular/sangre , Carcinoma Hepatocelular/patología , Quimioembolización Terapéutica , Progresión de la Enfermedad , Femenino , Humanos , Hígado/patología , Neoplasias Hepáticas/sangre , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Resultado del Tratamiento
6.
Clin Cancer Res ; 19(15): 4218-27, 2013 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-23757355

RESUMEN

PURPOSE: Insulin-like growth factor-I (IGF-I) reflects hepatic synthetic function and plays an important role in the development and progression of various cancers. In this study, we investigated whether pretreatment serum IGF-I levels predict time-to-recurrence (TTR) and overall survival (OS) in patients with early-stage hepatocellular carcinoma after curative treatment. EXPERIMENTAL DESIGN: Consecutive patients with hepatocellular carcinoma who had undergone surgical resection, radiofrequency ablation, or percutaneous ethanol injection as curative treatments of early hepatocellular carcinoma were included from two prospective cohorts and the training set (n = 101) and the validation set (n = 91) were established. Serum samples were collected before treatment and the levels of IGF-I and IGF-binding protein-3 (IGFBP-3) were analyzed with regard to their associations with recurrence and survival. RESULTS: In the training set, patients with low IGF-I levels showed significantly shorter TTR [median, 14.6 months; 95% confidence interval (CI), 1.8-27.5] than patients with high IGF-I levels (median, 50.8 months; 95% CI, 36.9-64.7; P < 0.001) during a median follow-up period of 52.4 months. In the multivariate analysis, low levels of IGF-I were an independent predictor of recurrence (HR, 2.49; 95% CI, 1.52-4.08; P < 0.001). Furthermore, together with high-serum α-fetoprotein and multiple tumors, low levels of IGF-I remained an independent predictor of poorer survival (HR, 8.00; 95% CI, 1.94-33.01; P = 0.004). Applied to the independent validation set, low-serum IGF-I levels maintained their prognostic value for shorter TTR and OS. CONCLUSIONS: Low-baseline IGF-I levels independently correlated with shorter TTR and poorer survival in patients with early-stage hepatocellular carcinoma after curative treatment.


Asunto(s)
Carcinoma Hepatocelular/patología , Factor I del Crecimiento Similar a la Insulina/metabolismo , Neoplasias Hepáticas/patología , Recurrencia Local de Neoplasia/patología , Anciano , Biomarcadores de Tumor/sangre , Carcinoma Hepatocelular/sangre , Carcinoma Hepatocelular/genética , Progresión de la Enfermedad , Femenino , Humanos , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Neoplasias Hepáticas/sangre , Neoplasias Hepáticas/genética , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/sangre , Recurrencia Local de Neoplasia/metabolismo , Estadificación de Neoplasias , Pronóstico , Estudios Prospectivos , Suero/metabolismo , Análisis de Supervivencia
7.
Korean J Radiol ; 10(6): 596-603, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19885316

RESUMEN

OBJECTIVE: The purpose of this study was to compare the antitumor effect and hepatotoxicity of an intraarterial delivery of low-dose and high-dose 3-bromopyruvate (3-BrPA) and those of a conventional Lipiodol-doxorubicin emulsion in a rabbit VX2 hepatoma model. MATERIALS AND METHODS: This experiment was approved by the animal care committee at our institution. VX2 carcinoma was implanted in the livers of 36 rabbits. Transcatheter intraarterial administration was performed using low dose 3-BrPA (25 mL in a 1 mM concentration, n = 10), high dose 3-BrPA (25 mL in a 5 mM concentration, n = 10) and Lipiodol-doxorubicin emulsion (1.6 mg doxorubicin/ 0.4 mL Lipiodol, n = 10), and six rabbits were treated with normal saline alone as a control group. One week later, the proportion of tumor necrosis was calculated based on histopathologic examination. The hepatotoxicity was evaluated by biochemical analysis. The differences between these groups were statistically assessed with using Mann-Whitney U tests and Kruskal-Wallis tests. RESULTS: The tumor necrosis rate was significantly higher in the high dose group (93% +/- 7.6 [mean +/- SD]) than that in the control group (48% +/- 21.7) (p = 0.0002), but the tumor necrosis rate was not significantly higher in the low dose group (62% +/- 20.0) (p = 0.2780). However, the tumor necrosis rate of the high dose group was significantly lower than that of the Lipiodol-doxorubicin treatment group (99% +/- 2.7) (p = 0.0015). The hepatotoxicity observed in the 3-BrPA groups was comparable to that of the Lipiodol-doxorubicin group. CONCLUSION: Even though intraarterial delivery of 3-BrPA shows a dose-related antitumor effect, single session treatment seems to have limited efficacy when compared with the conventional method.


Asunto(s)
Neoplasias Hepáticas Experimentales/tratamiento farmacológico , Piruvatos/farmacología , Animales , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Doxorrubicina/administración & dosificación , Doxorrubicina/farmacología , Infusiones Intraarteriales , Aceite Yodado/administración & dosificación , Aceite Yodado/farmacología , Neoplasias Hepáticas Experimentales/diagnóstico por imagen , Piruvatos/administración & dosificación , Conejos , Estadísticas no Paramétricas , Tomografía Computarizada por Rayos X
8.
Mod Pathol ; 16(5): 403-10, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12748245

RESUMEN

To determine the most optimal treatment of cancer patients, it is fundamental to classify human carcinomas according to their primary anatomical site of origin. As for some patients, it is difficult to identify cancers occurring at obscure location and overlapping adjacent sites. The aim of this study is to partition the primary site of 486 patients in cancers of the digestive system by the expression pattern of the mucins and cytokeratins typifying each site. The expressions of MUC1, MUC2, MUC5AC, MUC6, CK7, CK8, CK13, CK14, CK18, CK19 and CK20 were evaluated immunohistochemically in 426 adenocarcinomas and 60 hepatocellular carcinomas using the tissue-array method. The finding of MUC series showed their characteristics in case of MUC2 in the appendix cancer and MUC1 and 5AC in pancreas cancer. As for CKs 7, 13, and 19, and 20 had a feature in cancers of common bile duct, liver, and appendix, respectively. We classified cancers in 11 sites by characteristic expression of antibodies. The sensitivity, specificity, positive predictive value, and diagnostic efficacy of significant antibodies were calculated with deducing the dichotomous tree made by SPSS 10.0. Six of 11 antibodies, CK 7, CK13, CK19, CK20, MUC1, and MUC5AC distinguished 6 groups from 11 sites. We also executed the clustering of cancers to investigate total relationship among cancers. They fell into three categories, which corresponded to embryologic origin. Unlike other sites, the small intestine and colorectum cancers expressed significantly different patterns to their sublocations. Mucins and CKs showed expression patterns to classify the primary sites of digestive cancers and may be helpful in predicting the primary sites of digestive cancers.


Asunto(s)
Adenocarcinoma/metabolismo , Neoplasias del Sistema Digestivo/metabolismo , Queratinas/metabolismo , Mucinas/metabolismo , Adenocarcinoma/clasificación , Adenocarcinoma/patología , Biomarcadores de Tumor/metabolismo , Análisis por Conglomerados , Árboles de Decisión , Neoplasias del Sistema Digestivo/clasificación , Neoplasias del Sistema Digestivo/patología , Humanos , Técnicas para Inmunoenzimas , Análisis por Matrices de Proteínas/métodos , Adhesión del Tejido/métodos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA