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1.
Small ; : e2403737, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949018

RESUMO

In next-generation neuromorphic computing applications, the primary challenge lies in achieving energy-efficient and reliable memristors while minimizing their energy consumption to a level comparable to that of biological synapses. In this work, hexagonal boron nitride (h-BN)-based metal-insulator-semiconductor (MIS) memristors operating is presented at the attojoule-level tailored for high-performance artificial neural networks. The memristors benefit from a wafer-scale uniform h-BN resistive switching medium grown directly on a highly doped Si wafer using metal-organic chemical vapor deposition (MOCVD), resulting in outstanding reliability and low variability. Notably, the h-BN-based memristors exhibit exceptionally low energy consumption of attojoule levels, coupled with fast switching speed. The switching mechanisms are systematically substantiated by electrical and nano-structural analysis, confirming that the h-BN layer facilitates the resistive switching with extremely low high resistance states (HRS) and the native SiOx on Si contributes to suppressing excessive current, enabling attojoule-level energy consumption. Furthermore, the formation of atomic-scale conductive filaments leads to remarkably fast response times within the nanosecond range, and allows for the attainment of multi-resistance states, making these memristors well-suited for next-generation neuromorphic applications. The h-BN-based MIS memristors hold the potential to revolutionize energy consumption limitations in neuromorphic devices, bridging the gap between artificial and biological synapses.

2.
Small ; 19(35): e2301190, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37096899

RESUMO

Silicon nanostructures (SiNSs) can provide multifaceted bioapplications; but preserving their subhundred nm size during high-temperature silica-to-silicon conversion is the major bottleneck. The SC-SSR utilizes an interior metal-silicide stratum space at a predetermined radial distance inside silica nanosphere to guide the magnesiothermic reduction reaction (MTR)-mediated synthesis of hollow and porous SiNSs. In depth mechanistic study explores solid-to-hollow transformation encompassing predefined radial boundary through the participation of metal-silicide species directing the in-situ formed Si-phase accumulation within the narrow stratum. Evolving thin-porous Si-shell remains well protected by the in-situ segregated MgO emerging as a protective cast against the heat-induced deformation and interparticle sintering. Retrieved hydrophilic SiNSs (<100 nm) can be conveniently processed in different biomedia as colloidal solutions and endocytosized inside cells as photoluminescence (PL)-based bioimaging probes. Inside the cell, rattle-like SiNSs encapsulated with Pd nanocrystals can function as biorthogonal nanoreactors to catalyze intracellular synthesis of probe molecules through C-C cross coupling reaction.


Assuntos
Nanosferas , Nanoestruturas , Silício/química , Nanoestruturas/química , Dióxido de Silício/química , Nanosferas/química , Porosidade
3.
Mar Drugs ; 21(10)2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37888448

RESUMO

Osteoarthritis (OA) is characterized by progressive cartilage destruction and synovitis; however, there are no approved disease-modifying OA drugs. Krill oil (KO) has been reported to possess anti-inflammatory properties and alleviate joint pain in knee OA, indicating its potential to target the inflammatory mechanism of OA. Therefore, the anti-OA effects of KO were investigated in primary chondrocytes and a surgical rat model of knee OA. The oral administration of KO at 200 and 100 mg/kg for 8 weeks improved joint swelling and mobility in the animal model and led to increased bone mineral density and compressive strength in the cartilage. The oral KO doses upregulated chondrogenic genes (type 2 collagen, aggrecan, and Sox9), with inhibition of inflammation markers (5-lipoxygenase and prostaglandin E2) and extracellular matrix (ECM)-degrading enzymes (MMP-2 and MMP-9) in the cartilage and synovium. Consistently, KO treatments increased the viability of chondrocytes exposed to interleukin 1α, accompanied by the upregulation of the chondrogenic genes and the inhibition of the ECM-degrading enzymes. Furthermore, KO demonstrated inhibitory effects on lipopolysaccharide-induced chondrocyte inflammation. Histopathological and immunohistochemical analyses revealed that KO improved joint destruction and synovial inflammation, probably due to the anti-inflammatory, anti-apoptotic, and chondrogenic effects. These findings suggest the therapeutic potential of KO for knee OA.


Assuntos
Cartilagem Articular , Euphausiacea , Osteoartrite do Joelho , Ratos , Animais , Osteoartrite do Joelho/tratamento farmacológico , Osteoartrite do Joelho/genética , Osteoartrite do Joelho/patologia , Condrócitos , Inflamação/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Células Cultivadas
4.
Int J Mol Sci ; 24(11)2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37298425

RESUMO

Hormone receptor-positive breast cancer (HR+ BC) cells depend on estrogen and its receptor, ER. Due to this dependence, endocrine therapy (ET) such as aromatase inhibitor (AI) treatment is now possible. However, ET resistance (ET-R) occurs frequently and is a priority in HR+ BC research. The effects of estrogen have typically been determined under a special culture condition, i.e., phenol red-free media supplemented with dextran-coated charcoal-stripped fetal bovine serum (CS-FBS). However, CS-FBS has some limitations, such as not being fully defined or ordinary. Therefore, we attempted to find new experimental conditions and related mechanisms to improve cellular estrogen responsiveness based on the standard culture medium supplemented with normal FBS and phenol red. The hypothesis of pleiotropic estrogen effects led to the discovery that T47D cells respond well to estrogen under low cell density and medium replacement. These conditions made ET less effective there. The fact that several BC cell culture supernatants reversed these findings implies that housekeeping autocrine factors regulate estrogen and ET responsiveness. Results reproduced in T47D subclone and MCF-7 cells highlight that these phenomena are general among HR+ BC cells. Our findings offer not only new insights into ET-R but also a new experimental model for future ET-R studies.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Estrogênios/farmacologia , Inibidores da Aromatase/farmacologia , Células MCF-7 , Fenolsulfonaftaleína/farmacologia
5.
Medicina (Kaunas) ; 59(11)2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-38004077

RESUMO

Background and Objectives: This study evaluated the in vitro anti-adipogenic and anti-inflammatory properties of black cumin (Nigella sativa L.) seed extract (BCS extract) as a potential candidate for developing herbal formulations targeting metabolic disorders. Materials and Methods: We evaluated the BCS extract by assessing its 2,2-diphenyl-1-picrohydrazyl (DPPH) radical scavenging activity, levels of prostaglandin E2 (PGE2) and nitric oxide (NO), and mRNA expression levels of key pro-inflammatory mediators. We also quantified the phosphorylation of nuclear factor kappa light chain enhancer of activated B cells (NF-κB) and mitogen-activated protein kinases (MAPK) signaling molecules. To assess anti-adipogenic effects, we used differentiated 3T3-L1 cells and BCS extract in doses from 10 to 100 µg/mL. We also determined mRNA levels of key adipogenic genes, including peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer binding protein α (C/BEPα), adipocyte protein 2 (aP2), lipoprotein lipase (LPL), fatty acid synthase (FAS), and sterol-regulated element-binding protein 1c (SREBP-1c) using real-time quantitative polymerase chain reaction (qPCR). Results: This study showed a concentration-dependent DPPH radical scavenging activity and no toxicity at concentrations up to 30 µg/mL in Raw264.7 cells. BCS extract showed an IC50 of 328.77 ± 20.52 µg/mL. Notably, pre-treatment with BCS extract (30 µg/mL) significantly enhanced cell viability in lipopolysaccharide (LPS)-treated Raw264.7 cells. BCS extract treatment effectively inhibited LPS-induced production of PGE2 and NO, as well as the expression of monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-α (TNF-α), cyclooxygenase-2 (COX-2), inducible NO synthase (iNOS), interleukin (IL)-1ß and IL-6, possibly by limiting the phosphorylation of p38, p65, inhibitory κBα (I-κBα), and c-Jun N-terminal kinase (JNK). It also significantly attenuated lipid accumulation and key adipogenic genes in 3T3-L1 cells. Conclusions: This study highlights the in vitro anti-adipogenic and anti-inflammatory potential of BCS extract, underscoring its potential as a promising candidate for managing metabolic disorders.


Assuntos
Doenças Metabólicas , Nigella sativa , Humanos , Animais , Camundongos , Nigella sativa/metabolismo , Células 3T3-L1 , Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Extratos Vegetais/química , Macrófagos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Adipócitos , Sementes , RNA Mensageiro/metabolismo , Doenças Metabólicas/metabolismo , Óxido Nítrico/metabolismo
6.
Mar Drugs ; 20(8)2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-36005486

RESUMO

Obesity increases the risks of metabolic syndromes including nonalcoholic fatty liver disease (NAFLD), diabetic dyslipidemia, and chronic kidney disease. Dietary krill oil (KO) has shown antioxidant and anti-inflammatory properties, thereby being a therapeutic potential for obesity-induced metabolic syndromes. Thus, the effects of KO on lipid metabolic alteration were examined in a high-fat diet (HFD)-fed mice model. The HFD model (n = 10 per group) received an oral gavage with distilled water as a control, metformin at 250 mg/kg, and KO at 400, 200, and 100 mg/kg for 12 weeks. The HFD-induced weight gain and fat deposition were significantly reduced in the KO treatments compared with the control. Blood levels were lower in parameters for NAFLD (e.g., alanine aminotransferase, and triglyceride), type 2 diabetes (e.g., glucose and insulin), and renal dysfunction (e.g., blood urea nitrogen and creatinine) by the KO treatments. The KO inhibited lipid synthesis through the modification of gene expressions in the liver and adipose tissues and adipokine-mediated pathways. Furthermore, KO showed hepatic antioxidant activities and glucose lowering effects. Histopathological analyses revealed that the KO ameliorated the hepatic steatosis, pancreatic endocrine/exocrine alteration, adipose tissue hypertrophy, and renal steatosis. These analyses suggest that KO may be promising for inhibiting obesity and metabolic syndromes.


Assuntos
Diabetes Mellitus Tipo 2 , Euphausiacea , Resistência à Insulina , Síndrome Metabólica , Hepatopatia Gordurosa não Alcoólica , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Diabetes Mellitus Tipo 2/metabolismo , Dieta Hiperlipídica/efeitos adversos , Glucose/metabolismo , Fígado , Síndrome Metabólica/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Obesidade/complicações , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Triglicerídeos/metabolismo
7.
J Am Chem Soc ; 143(3): 1399-1408, 2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33332964

RESUMO

Developing efficient and inexpensive electrocatalysts for the hydrogen evolution reaction (HER) in alkaline water electrolysis plays a key role for renewable hydrogen energy technology. The slow reaction kinetics of HER in alkaline solutions, however, has hampered advances in high-performance hydrogen production. Herein, we investigated the trends in HER activity with respect to the binding energies of Ni-based thin film catalysts by incorporating a series of oxophilic transition metal atoms. It was found that the doping of oxophilic atoms enables the modulation of binding abilities of hydrogen and hydroxyl ions on the Ni surfaces, leading to the first establishment of a volcano relation between OH-binding energies and alkaline HER activities. In particular, Cr-incorporated Ni catalyst shows optimized OH-binding as well as H-binding energies for facilitating water dissociation and improving HER activity in alkaline media. Further enhancement of catalytic performance was achieved by introducing an array of three-dimensional (3D) Ni nanohelixes (NHs) that provide abundant surface active sites and effective channels for charge transfer and mass transport. The Cr dopants incorporated into the Ni NHs accelerate the dissociative adsorption process of water, resulting in remarkably enhanced catalytic activities in alkaline medium. Our approach can provide a rational design strategy and experimental methodology toward efficient bimetallic electrocatalysts for alkaline HER using earth-abundant elements.

8.
Small ; 17(47): e2103861, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34553492

RESUMO

An array of SnO2 nanohelix structures is employed to fabricate a SnO2 helix@ZnFe2 O4 dendrite core-shell 3D heterostructure photoanode for photoelectrochemical (PEC) water splitting. The SnO2 helix provides triple critical functions to enhance the PEC performance of the photoanode. First, it scatters the incident light to achieve a higher light harvesting efficiency. Second, it provides a facile electron pathway as an electron transfer layer (ETL) while blocking hole transport to mitigate charge recombination in the bulk of ZnFe2 O4 . Finally, it becomes a template for the formation of ZnFe2 O4 dendrite nanostructure shell. The ZnFe2 O4 dendrite/SnO2 helix photoanode exhibits a remarkable increase in incident photon-to-electron conversion efficiency compared to unmodified ZnFe2 O4 with no ETL and modified one with "flat" SnO2 ETL. The surface of the ZnFe2 O4 /SnO2 helix photoanode is further modified with TiO2 passivation layer and NiFeOx oxygen evolution co-catalyst to achieve one of the best PEC performances among reported ZnFe2 O4 -based photoanodes.

9.
Molecules ; 26(10)2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-34070099

RESUMO

Wild ginseng has better pharmacological effects than cultivated ginseng. However, its industrialization is limited by the inability to grow wild ginseng on a large scale. Herein, we demonstrate how to optimize ginseng production through cultivation, and how to enhance the concentrations of specific ginsenosides through fermentation. In the study, we also evaluated the ability of fermented cultured wild ginseng root extract (HLJG0701-ß) to inhibit acetylcholinesterase (AChE), as well as its neuroprotective effects and antioxidant activity. In invitro tests, HLJG0701-ß inhibited AChE activity and exerted neuroprotective and antioxidant effects (showing increased catalyst activity but decreased reactive oxygen species concentration). In invivo tests, after HLJG0701-ß was orally administered at doses of 0, 125, 250, and 500 mg/kg in an animal model of memory impairment, behavioral evaluation (Morris water maze test and Y-maze task test) was performed. The levels of AChE, acetylcholine (ACh), blood catalase (CAT), and malondialdehyde (MDA) in brain tissues were measured. The results showed that HLJG0701-ß produced the best results at a dose of 250 mg/kg or more. The neuroprotective mechanism of HLJG0701-ß was determined to involve the inhibition of AChE activity and a decrease in oxidative stress. In summary, both invitro and invivo tests confirmed that HJG0701-ß administration can lead to memory improvement.


Assuntos
Antioxidantes/farmacologia , Fermentação , Fármacos Neuroprotetores/farmacologia , Panax/química , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Acetilcolina/metabolismo , Acetilcolinesterase/metabolismo , Animais , Encéfalo/metabolismo , Catalase/sangue , Catalase/metabolismo , Inibidores da Colinesterase/farmacologia , Modelos Animais de Doenças , Feminino , Galactose , Ginsenosídeos/farmacologia , Masculino , Malondialdeído/sangue , Camundongos , Teste do Labirinto Aquático de Morris , Ovariectomia , Espécies Reativas de Oxigênio/metabolismo , Escopolamina
10.
Nano Lett ; 19(3): 1814-1820, 2019 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-30779586

RESUMO

We have achieved heteroepitaxial stacking of a van der Waals ( vdW) monolayer metal, 1T'-WTe2, and a semiconductor, 2H-WSe2, in which a distinctively low contact barrier was established across a clean epitaxial vdW gap. Our epitaxial 1T'-WTe2 films were identified as a semimetal by low temperature transport and showed the robust breakdown current density of 5.0 × 107 A/cm2. In comparison with a series of planar metal contacts, our epitaxial vdW contact was identified to possess intrinsic Schottky barrier heights below 100 meV for both electron and hole injections, contributing to superior ambipolar field-effect transistor (FET) characteristics, i.e., higher FET mobilities and higher on-off current ratios at smaller threshold gate voltages. We discuss our observations around the critical roles of the epitaxial vdW heterointerfaces, such as incommensurate stacking sequences and absence of extrinsic interfacial defects that are inaccessible by other contact methods.

11.
Opt Express ; 27(14): 19692-19701, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31503725

RESUMO

Two-dimensional (2-D) hexagonal boron nitride (h-BN) has attracted considerable attention for deep ultraviolet optoelectronics and visible single photon sources, however, realization of an electrically-driven light emitter remains challenging due to its wide bandgap nature. Here, we report electrically-driven visible light emission with a red-shift under increasing electric field from a few layer h-BN by employing a five-period Al2O3/h-BN multiple heterostructure and a graphene top electrode. Investigation of electrical properties reveals that the Al2O3 layers act as potential barriers confining injected carriers within the h-BN wells, while suppressing the electrostatic breakdown by trap-assisted tunneling, to increase the probability of radiative recombination. The result highlights a promising potential of such multiple heterostructure as a practical and efficient platform for electrically-driven light emitters based on wide bandgap two-dimensional materials.

12.
Nanotechnology ; 30(11): 115501, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30561379

RESUMO

We present a gas sensor having nanoscale Schottky contacts on an array of helical-shaped p-type NiO to overcome intrinsically ineffective resistance modulation in the bulk of p-type metal oxides upon gas exposure. The Schottky device shows an abnormal n-type sensing behavior despite using the p-type NiO under reducing gas, with the sensitivity of 142.9% at 200 ppm of hydrogen, much higher than the reference Ohmic device with 0.7% sensitivity. Based on our equivalent circuit model with the quantitative estimation of the modulations in both carrier concentration and Schottky barrier height upon gas exposure, such a high sensitivity and the abnormal sensing behavior are attributed to the predominant modulation in the barrier height at the nanoscale Schottky contacts which are uniquely designed to have top-and-bottom electrodes configuration for efficient gas adsorption and sensitive Schottky barrier height modulation.

13.
J Nanosci Nanotechnol ; 19(2): 1137-1140, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30360218

RESUMO

Nano MgFe-TiO2 photocatalyst was prepared by mixing nanoscale spinel compounds such as magnesium ferrite (MgFe) and TiO2. The cations produced by MgFe are affected by various influencing factors such as calcination temperature, precursor, and mass ratio of Mg and Fe. This study is to evaluate the photocatalytic efficiency of nano MgFe-doped TiO2 under visible light according to the composition ratio of Mg, Fe and TiO2. With an increase the percentage of doping (i.e., Mg and Fe) over TiO2, the band gap between conduction band and valance band decreases, therefore showing better photocatalytic activity in visible light. Also as percentage of doping over TiO2 increases, surface area of the catalyst also increases subsequently resulting in an increase in the adsorption capacity.

14.
J Nanosci Nanotechnol ; 19(2): 1014-1017, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30360192

RESUMO

Novel composites with nano-sized TiO2 synthesized on the surface of bottom ash (NTB) were prepared for treatment of spent sulfidic caustic (SSC) wastewater. The efficiency of SSC wastewater treatment was compared and evaluated by using NTBs made with organic binder and inorganic binder, respectively. The treatment efficiency of NTB composite made with organic binder was higher than that of NTB composite made with inorganic binder. Although NBT composite made with inorganic binder had many pores on the surface, the white cement used as binder was excessively applied to the surface, and amount of coated nano-sized TiO2 was decreased. The photocatalytic activity of nano-sized TiO2 is more effective for SSC wastewater treatment than surface adsorption ability of surface pores.

15.
J Nanosci Nanotechnol ; 19(2): 1065-1068, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30360202

RESUMO

A new immobilization technique of nanoscale TiO2 powders to expanded polystryrene (EPS) balls with temperature-controlled melting method was developed for mass production, and the characterization of TiO2 powder-embedded EPS (TiEPS) balls was evaluated. Based on the scanning electron microscope (SEM) images and associated energy-dispersive X-ray spectroscopy (EDX) analysis, the components of intact EPS balls are carbon and oxygen whereas those of TiEPS balls are carbon, oxygen, and titanium, indicating that TiO2 powders were embedded on the surface of EPS balls. As also evident by the X-ray diffraction (XRD) and FTIR analyses, no significant changes in crystalline structure of TiO2 powders embedded on the EPS balls were found during the preparation and application processes of TiEPS balls. These characterization results indicated that the patches of TiO2 powders were soundly impregnated over the surface of EPS balls without the significant changes in crystalline structure of TiO2 powders and both structural changes and deformation of EPS polymer.

16.
J Nanosci Nanotechnol ; 19(2): 1151-1154, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30360222

RESUMO

A new immobilization technique of nanoscale TiO2 powders to expanded polystryrene (EPS) balls with temperature-controlled melting method was validated for mass production, and the photocatalytic activity of TiO2 powder-embedded EPS (TiEPS) balls using methylene blue (MB) solution with different concentrations under ultraviolet irradiation and under the natural solar light irradiation. Whereas MB molecules were weakly adsorbed onto the surface of both TiO2 powders and supporting polymers without any specific interactions, the photocatalytic efficiency of TiEPS balls with UV (Kapp =0.016~0.043 min-1) was greater through coupled reaction processes (adsorption, photolysis, and photocatalysis). After 5-min sonication, more TiO2 powders on the TiEPS balls can be involved into the both adsorption and photocatalytic reactions of MB, and can increase the MB removal efficiencies. TiEPS balls can be reused for several consecutive runs without any significant decrease in photocatalytic activity until the recalcitrant contaminants were completely coated on the surface of TiEPS balls and loss of TiO2 powders embedded on the surface of TiEPS balls was significant. Based on the aforementioned results, self-floating TiEPS balls manufactured from this simple and cost-effective melting method can be used to remove the organic contaminants and to inhibit the excessive growth of harmful algae in the stagnant water body.

17.
Nano Lett ; 18(7): 4257-4262, 2018 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-29902008

RESUMO

Despite a longstanding controversy surrounding TiO2 materials, TiO2 polymorphs with heterojunctions composed of anatase and rutile outperform individual polymorphs because of the type-II energetic band alignment at the heterojunction interface. Improvement in photocatalysis has also been achieved via black TiO2 with a thin disorder layer surrounding ordered TiO2. However, localization of this disorder layer in a conventional single TiO2 nanoparticle with the heterojunction composed of anatase and rutile has remained a big challenge. Here, we report the selective positioning of a disorder layer of controlled thicknesses between the anatase and rutile phases by a conceptually different synthetic route to access highly efficient novel metal-free photocatalysis for H2 production. The presence of a localized disorder layer within a single TiO2 nanoparticle was confirmed for the first time by high-resolution transmission electron microscopy with electron energy-loss spectroscopy and inline electron holography. Multiple heterojunctions in single TiO2 nanoparticles composed of crystalline anatase/disordered rutile/ordered rutile layers give the nanoparticles superior electron/hole separation efficiency and novel metal-free surface reactivity, which concomitantly yields an H2 production rate that is ∼11-times higher than that of Pt-decorated conventional anatase and rutile single heterojunction TiO2 systems.

18.
Ann Surg Oncol ; 25(6): 1775-1781, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29611028

RESUMO

BACKGROUND: BRAFV600E mutation is the most common somatic variant in papillary thyroid carcinoma (PTC) and is associated with aggressive prognostic factors. The conventional detection method for BRAF mutations is polymerase chain reaction followed by Sanger sequencing. Recently, an immunohistochemistry (IHC) method using a BRAFV600E-specific antibody (VE1) has been developed and widely adopted in the clinics; however, there is a lack of evidence regarding the comparability of the IHC and Sanger sequencing methods. METHODS: Our institution began using the BRAFV600E IHC test in January 2013. We retrospectively analyzed 697 samples that were tested using both the IHC and sequencing methods, and evaluated their concordance. RESULTS: BRAF mutation was detected in 90.0% (627/697) of samples using IHC and 83.4% (581/697) of samples using direct sequencing. The diagnostic parameters of IHC compared with Sanger sequencing were as follows: 100% sensitivity (581/581), 60.3% specificity (70/116), 92.7% positive predictive value (581/627), and 100% negative predictive value (70/70). No false negative results were recorded using IHC. The overall concordance rate between the two methods was 93.4% (651/697). Discordant results were found in 46 samples (6.6%), 29 of which were from cases with small tumors (< 6 mm), 8 were from cases with low tumor cellularity, and 9 were specimens yielding low-quality DNA. CONCLUSIONS: IHC using the VE1 antibody is a reliable and highly sensitive method for detecting the BRAFV600E mutation in classic PTC.


Assuntos
DNA de Neoplasias/análise , Imuno-Histoquímica/métodos , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Análise de Sequência de DNA/métodos , Câncer Papilífero da Tireoide/genética , Neoplasias da Glândula Tireoide/genética , Adulto , Reações Falso-Negativas , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Mutação , Invasividade Neoplásica , Valor Preditivo dos Testes , Estudos Retrospectivos , Câncer Papilífero da Tireoide/diagnóstico , Câncer Papilífero da Tireoide/metabolismo , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/patologia , Carga Tumoral
19.
J Gastroenterol Hepatol ; 33(6): 1200-1206, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29205498

RESUMO

BACKGROUND AND AIM: In some patients with ulcerative proctitis (UP), skip inflammation is noted in the right side of the colon, but little is known about its clinical course. The aim of this study was to evaluate the clinical course of UP with skip inflammation and the efficacy of topical 5-aminosalicylate (5-ASA) monotherapy. METHODS: This study reviewed the data of 388 patients with an initial diagnosis of UP from January 2005 to October 2015. This study matched each UP patient with skip inflammation 1:2 with controls who had UP without skip inflammation; to reduce bias, this study matched the controls with the cases by age, gender, and initial disease activity. RESULTS: During the follow-up period (median: 69.5 months), the overall progression rates for the control group (n = 192) and the skip inflammation group (n = 96) were 24.0% and 32.9% at 10 years, respectively (log-rank P = 0.71). In the skip inflammation group, the progression rates were not significantly different between the 5-ASA combination group and the topical group, 33.4% and 26.6% at 10 years, respectively (log-rank P = 0.96). The overall acute exacerbation rates for the control and skip inflammation groups were 17.2% and 26.8% at 10 years, respectively (log-rank P = 0.68). In the skip inflammation group, the exacerbation rates were also not significantly different between the combination and topical treatment groups, 26.6% and 23.6% at 10 years, respectively (log-rank P = 0.88). CONCLUSION: The clinical course of UP with skip inflammation was not different from that of typical UP, and topical 5-ASA monotherapy for maintaining remission was as effective as 5-ASA combination therapy irrespective of the presence of skip lesions.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Dermatite/tratamento farmacológico , Dermatite/etiologia , Mesalamina/administração & dosagem , Proctocolite/complicações , Proctocolite/tratamento farmacológico , Administração Oftálmica , Administração Tópica , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Quimioterapia de Manutenção , Masculino , Pessoa de Meia-Idade , Fenil-Hidrazinas/administração & dosagem , Indução de Remissão , Resultado do Tratamento , Adulto Jovem
20.
Surg Endosc ; 32(3): 1360-1367, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28842763

RESUMO

BACKGROUND: Bilateral axillo-breast approach robotic thyroidectomy (BABA RT) is an excellent surgical method, being oncologically safe and with anatomic views similar to those of open surgery. BABA RT, however, requires training and a learning curve for proficiency. We evaluated the educational effectiveness of a surgical training model for BABA RT, comparing objective BABA scores with scores on the da Vinci Skills Simulator (dVSS). METHODS: Medical students, surgical residents, and surgical fellows performed structured tasks with the BABA training model and dVSS under the same conditions. All tasks were videotaped. BABA scores were compared with dVSS scores and with objective evaluation scores (GEARS and OSATS). RESULTS: Eight medical students, ten surgical residents, and eight surgical fellows participated in this study. The educational effect of BABA training improved from one to two (p < 0.001), two to three (p = 0.003), and one to three (p < 0.001) procedures. Statistically significant differences were found when students were compared with residents (p = 0.025) and fellows (p < 0.001) in the BABA training model, and between students and fellows (p = 0.004) in dVSS. BABA scores showed similar distribution patterns in the three groups to GEARS and OSATS scores (p < 0.001 each). CONCLUSIONS: The BABA training model is an excellent educational tool for surgical residents and surgical fellows to learn and practice BABA RT. Assessment by BABA score yielded objective results comparable to those of traditional scoring methodologies.


Assuntos
Modelos Anatômicos , Procedimentos Cirúrgicos Robóticos/educação , Treinamento por Simulação , Tireoidectomia/educação , Adulto , Axila , Mama , Competência Clínica , Feminino , Humanos , Tireoidectomia/métodos , Adulto Jovem
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