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1.
ACS Appl Mater Interfaces ; 16(23): 30228-30238, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38810990

RESUMEN

A bottom-contact organic field-effect transistor (OFET) is easily adaptable to the standard lithography process because the contact electrodes are deposited before the organic semiconductor (OSC). However, the low surface energy of bare electrodes limits utilizing solution-processed single-crystal OSCs. Additionally, the bare electrode usually leads to a significant charge injection barrier, owing to its relatively low work function (WF). Here, we simultaneously improved the surface energy and WF of gold electrodes by conducting oxygen plasma treatment to achieve high-performance OFET based on solution-processed organic single crystals. We cultivated a thin layer of gold oxide on Au electrodes to increase the WF by ∼0.7 eV. The surface energy of Au electrodes was enhanced to the same as AlOx dielectric surface, enabling the seamless growth of large-area C8-BTBT (2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene) organic single-crystal thin films via solution shearing. This technique facilitates the production of high-performance OFETs with the highest carrier mobility of 6.7 cm2 V-1 s-1 and sharp switching characterized by a subthreshold swing of 63.6 mV dec-1. The bottom-contact OFETs exhibited a lower contact resistance of 1.19 kΩ cm than its F4-TCNQ-doped top-contact control device. This method offers a straightforward and effective strategy for producing high-quality single-crystal OFETs, which are potentially suitable for commercial applications.

2.
Proc Natl Acad Sci U S A ; 120(24): e2304506120, 2023 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-37279276

RESUMEN

Dynamic molecular devices operating with time- and history-dependent performance raised new challenges for the fundamental study of microscopic non-steady-state charge transport as well as functionalities that are not achievable by steady-state devices. In this study, we reported a generic dynamic mode of molecular devices by addressing the transient redox state of ubiquitous quinone molecules in the junction by proton/water transfer. The diffusion limited slow proton/water transfer-modulated fast electron transport, leading to a non-steady-state transport process, as manifested by the negative differential resistance, dynamic hysteresis, and memory-like behavior. A quantitative paradigm for the study of the non-steady-state charge transport kinetics was further developed by combining the theoretical model and transient state characterization, and the principle of the dynamic device can be revealed by the numerical simulator. On applying pulse stimulation, the dynamic device emulated the neuron synaptic response with frequency-dependent depression and facilitation, implying a great potential for future nonlinear and brain-inspired devices.

3.
Diagnostics (Basel) ; 13(3)2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36766641

RESUMEN

Artificial intelligence (AI) has been steadily developing in the medical field in the past few years, and AI-based applications have advanced cancer diagnosis. Breast cancer has a massive amount of data in oncology. There has been a high level of research enthusiasm to apply AI techniques to assist in breast cancer diagnosis and improve doctors' efficiency. However, the wise utilization of tedious breast cancer-related medical care is still challenging. Over the past few years, AI-based NLP applications have been increasingly proposed in breast cancer. In this systematic review, we conduct the review using preferred reporting items for systematic reviews and meta-analyses (PRISMA) and investigate the recent five years of literature in natural language processing (NLP)-based AI applications. This systematic review aims to uncover the recent trends in this area, close the research gap, and help doctors better understand the NLP application pipeline. We first conduct an initial literature search of 202 publications from Scopus, Web of Science, PubMed, Google Scholar, and the Association for Computational Linguistics (ACL) Anthology. Then, we screen the literature based on inclusion and exclusion criteria. Next, we categorize and analyze the advantages and disadvantages of the different machine learning models. We also discuss the current challenges, such as the lack of a public dataset. Furthermore, we suggest some promising future directions, including semi-supervised learning, active learning, and transfer learning.

4.
Diagnostics (Basel) ; 13(2)2023 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-36673096

RESUMEN

In the era of big data, text-based medical data, such as electronic health records (EHR) and electronic medical records (EMR), are growing rapidly. EHR and EMR are collected from patients to record their basic information, lab tests, vital signs, clinical notes, and reports. EHR and EMR contain the helpful information to assist oncologists in computer-aided diagnosis and decision making. However, it is time consuming for doctors to extract the valuable information they need and analyze the information from the EHR and EMR data. Recently, more and more research works have applied natural language processing (NLP) techniques, i.e., rule-based, machine learning-based, and deep learning-based techniques, on the EHR and EMR data for computer-aided diagnosis in oncology. The objective of this review is to narratively review the recent progress in the area of NLP applications for computer-aided diagnosis in oncology. Moreover, we intend to reduce the research gap between artificial intelligence (AI) experts and clinical specialists to design better NLP applications. We originally identified 295 articles from the three electronic databases: PubMed, Google Scholar, and ACL Anthology; then, we removed the duplicated papers and manually screened the irrelevant papers based on the content of the abstract; finally, we included a total of 23 articles after the screening process of the literature review. Furthermore, we provided an in-depth analysis and categorized these studies into seven cancer types: breast cancer, lung cancer, liver cancer, prostate cancer, pancreatic cancer, colorectal cancer, and brain tumors. Additionally, we identified the current limitations of NLP applications on supporting the clinical practices and we suggest some promising future research directions in this paper.

5.
J Clin Sleep Med ; 12(11): 1453-1459, 2016 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-27568900

RESUMEN

STUDY OBJECTIVES: The present single-dose, parallel-group, randomized, double-blind, placebo-controlled study is to evaluate the pharmacokinetics, tolerability and safety of zolpidem tartrate nasal spray (ZNS) as compared to placebo in healthy subjects. METHODS: Thirty-six healthy subjects participated in this study, with 19 male and 17 female subjects in 3 cohorts (12 subjects per cohort), who were randomly assigned to receive either an intranasal dose of ZNS 1.75 mg, 3.5 mg, 5.0 mg (n = 10 per dose), or an intranasal placebo (n = 2). Multiple venous blood samples were collected for pharmacokinetic analyses. RESULTS: Plasma zolpidem concentrations rapidly increased after intranasal ZNS 1.75, 3.5, and 5.0 mg with mean Tmax of 0.42, 0.76 and 0.50 h, respectively, followed by rapid decreases at all three doses. Cmax, AUC0-t, and AUC0-∞ were found to increase in a dose-proportional manner. Female subjects had generally higher AUC0-t, AUC0-∞, and lower weight-normalized clearance rate (CL/F) than male subjects. In this study, ZNS was safe and well tolerated over the evaluated dose range. There were no serious adverse events. CONCLUSIONS: Zolpidem was rapidly absorbed and eliminated after intranasal administration of ZNS. Dose proportionality was found at the doses ranged from 1.75 mg to 5.0 mg. Intranasal exposure of zolpidem was generally higher in female subjects than that in male subjects. It could be concluded that ZNS is safe and well tolerated over the evaluated range of intranasal doses.


Asunto(s)
Hipnóticos y Sedantes/farmacocinética , Rociadores Nasales , Piridinas/farmacocinética , Trastornos del Inicio y del Mantenimiento del Sueño/tratamiento farmacológico , Adulto , Método Doble Ciego , Femenino , Humanos , Hipnóticos y Sedantes/administración & dosificación , Masculino , Piridinas/administración & dosificación , Taiwán , Resultado del Tratamiento , Adulto Joven , Zolpidem
6.
Arch Histol Cytol ; 71(2): 101-14, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18974602

RESUMEN

The perfusion-Perls and -Turnbull methods supplemented by diaminobenzidine intensification demonstrated the generation and localization of chelatable Fe (II) which can catalyze the generation of cytotoxic hydroxyl radicals (OH.) during the Fenton reaction in rat kidneys exposed to 40 min ischemia or 40 min-ischemia followed by 60 min-reperfusion. The kidneys exposed to 40 min-ischemia showed Fe (II)-deposits largely localized in the deeper half of the cortex, where the deposits densely filled the tubular cell nuclei, with a small amount of them in the cytoplasm of the proximal convoluted tubules (PCT). Intraluminally protruded or exfoliated tubular cell nuclei were also filled with the deposits. The kidneys subjected to 40 min-ischemia/ 60 min-reperfusion showed a more extensive distribution of Fe (II)-deposits, including most depths of the cortex. Furthermore, there were numerous exfoliated, Fe (II)-positive nuclei surrounded by a small amount of cytoplasm in the lumen of the PCT. These cells appeared to undergo apoptotic cell death since the lumen of strongly dilated, down-stream, proximal straight tubules were obstructed with numerous apoptotic cells in the kidneys exposed to 40 min-ischemia and 24 h-reperfusion. Pretreatment with a divalent metal chelator, 2, 2'-dipyridyl, effectively inhibited Fe (II)-staining, decreased the number of exfoliated cells in the kidneys with 40 min-ischemia/ 60 m-reperfusion, and decreased the number of apoptotic cells in the kidneys with 40 min-ischemia/24 h-reperfusion. The generation of highly reactive OH. during the Fe2+-catalyzed Fenton reaction was suggested to play a crucial role in ischemia/reperfusion-induced kidney injury.


Asunto(s)
2,2'-Dipiridil/farmacología , Quelantes/farmacología , Compuestos Férricos/metabolismo , Isquemia/metabolismo , Riñón/metabolismo , Daño por Reperfusión/metabolismo , Animales , Femenino , Histocitoquímica , Concentración de Iones de Hidrógeno , Perfusión , Ratas , Ratas Wistar , Factores de Tiempo
7.
Arch Histol Cytol ; 71(4): 205-22, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19359804

RESUMEN

Iron in the brain is utilized for cellular respiration, neurotransmitter synthesis/degradation, and myelin formation. Iron, especially its ferrous form, also has the potential for catalyzing the Fenton reaction to generate highly cytotoxic hydroxyl radicals. The amount of iron in the brain must therefore be strictly controlled. In this study, we focused on the cellular and subcellular localizations of nonheme ferric (Fe(III)) and ferrous (Fe(II)) iron in the adult female rat brain using light and electron microscopic histochemistry. Although Fe(II) deposition was much less dominant than Fe(III), the brain contained iron in both forms. Among the cellular elements of the brain, oligodendrocytes were numerically the most prominent and heavily iron-storing cells. Pericapillary astrocytes and sporadic microglial cells also showed dense iron accumulation. Large neurons involved in the motor system were relatively strongly iron-positive. Subcellularly, Fe(III) and Fe(II) were mainly localized in lysosomes, and occasionally in the cytosol and mitochondria. Furthermore, capillary endothelial cells had Fe(III)-positive reactions in lysosomes and the cytosol, with Fe(II)-positive reactions on the luminal membrane. With advancing age, both Fe(III) and Fe(II) became more extensively distributed and accumulated more numerously in oligodendrocytes and astrocytes. These findings suggest that age-related increases in Fe(II) accumulation may raise the risk of tissue damage in the normal brain.


Asunto(s)
Encéfalo/citología , Encéfalo/ultraestructura , Compuestos Férricos/química , Compuestos Ferrosos/química , Proteínas de Hierro no Heme/química , Oligodendroglía/química , Factores de Edad , Animales , Astrocitos/química , Encéfalo/metabolismo , Femenino , Microglía/química , Microglía/citología , Perfusión/métodos , Ratas , Ratas Wistar
8.
Arch Histol Cytol ; 70(1): 1-19, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17558140

RESUMEN

We reviewed the methods of nonheme-iron histochemistry with special focus on the underlying chemical principles. The term nonheme-iron includes heterogeneous species of iron complexes where iron is more loosely bound to low-molecular weight organic bases and proteins than that of heme (iron-protoporphyrin complex). Nonheme-iron is liberated in dilute acid solutions and available for conventional histochemistry by the Perls and Turnbull and other methods using iron chelators, which depend on the production of insoluble iron compounds. Treatment with strong oxidative agents is required for the liberation of heme-iron, which therefore is not stained by conventional histochemistry. The Perls method most commonly used in laboratory investigations largely stains ferric iron, but stains some ferrous iron as well, while the Turnbull method is specific for the latter. Although the Turnbull method performed on sections fails in staining ferrous iron or stains only such parts of the tissue where iron is heavily accumulated, an in vivo perfusion-Turnbull method demonstrated the ubiquitous distribution of ferrous iron, particularly in lysosomes. The Perls or Turnbull reaction is enhanced by DAB/silver/gold methods for electron microscopy. The iron sulfide method and the staining of redox-active iron with H(2)O(2) and DAB are also applicable for electron microscopy. Although the above histochemical methods have advantages for visualizing iron by conventional light and electron microscopy, the quantitative estimation of iron is not easy. Recent methods depending on the quenching of fluorescent divalent metal indicators by Fe(2+) and dequenching by divalent metal chelators have enabled the quantitative estimation of chelatable Fe(2+) in isolated viable cells.


Asunto(s)
Histocitoquímica/métodos , Hierro , Microscopía Electrónica/métodos , Microscopía/métodos , Coloración y Etiquetado/métodos , Animales , Compuestos Férricos/análisis , Compuestos Férricos/metabolismo , Compuestos Ferrosos/análisis , Compuestos Ferrosos/metabolismo , Historia del Siglo XIX , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Hierro/análisis , Hierro/historia , Hierro/metabolismo , Proteínas de Hierro no Heme/análisis , Proteínas de Hierro no Heme/metabolismo , Proteínas de Hierro no Heme/ultraestructura
9.
Arch Histol Cytol ; 68(3): 171-83, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16276023

RESUMEN

We previously developed the highly sensitive perfusion-Perls and -Turnbull methods to visualize nonheme ferric (Fe (III)) and ferrous (Fe (II)) iron, respectively. The present study used these methods to investigate the possible presence of nonheme iron in the redox (ferric/ferrous) state in the noneheme iron store (phagolysosomes and siderosomes) of resident macrophages in the rat. The perfusion-Perls and -Turnbull methods at pH 0.6 supplemented by DAB intensification intensely stained resident macrophages of different tissues and organs of normal and iron-overloaded rats. The perfusion-Turnbull method, which is specific for nonheme Fe (II), partly stained hemosiderin at pH 5.3, but hardly stained it at the physiological pH, suggesting the presence of some iron in the reduced form, free Fe2+ and/or loosely bound Fe (II), at the intravacuolar pH (5.4+/-0.2) of the phagolysosomes of macrophages. Electron microscopy of the splenic and hepatic macrophages treated by the perfusion-Perls or -Turnbull method showed that Fe (II) deposits were largely distributed along the margin of hemosiderin masses while Fe (III) deposits could also be found within hemosiderin masses.


Asunto(s)
Compuestos Férricos/metabolismo , Compuestos Ferrosos/análisis , Compuestos Ferrosos/metabolismo , Histocitoquímica/métodos , Perfusión/métodos , 3,3'-Diaminobencidina/química , 3,3'-Diaminobencidina/metabolismo , Animales , Femenino , Concentración de Iones de Hidrógeno , Hierro/metabolismo , Quelantes del Hierro/metabolismo , Quelantes del Hierro/farmacología , Sobrecarga de Hierro , Macrófagos del Hígado/metabolismo , Hígado/citología , Hígado/metabolismo , Macrófagos/química , Macrófagos/citología , Macrófagos/metabolismo , Oxidación-Reducción , Fagosomas , Ratas , Ratas Wistar , Nitrato de Plata/química , Nitrato de Plata/metabolismo , Bazo/citología , Bazo/metabolismo
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