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1.
Cereb Cortex ; 32(4): 668-688, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-34401898

RESUMO

Transient neocortical events with high spectral power in the 15-29 Hz beta band are among the most reliable predictors of sensory perception. Prestimulus beta event rates in primary somatosensory cortex correlate with sensory suppression, most effectively 100-300 ms before stimulus onset. However, the neural mechanisms underlying this perceptual association are unknown. We combined human magnetoencephalography (MEG) measurements with biophysical neural modeling to test potential cellular and circuit mechanisms that underlie observed correlations between prestimulus beta events and tactile detection. Extending prior studies, we found that simulated bursts from higher-order, nonlemniscal thalamus were sufficient to drive beta event generation and to recruit slow supragranular inhibition acting on a 300 ms timescale to suppress sensory information. Further analysis showed that the same beta-generating mechanism can lead to facilitated perception for a brief period when beta events occur simultaneously with tactile stimulation before inhibition is recruited. These findings were supported by close agreement between model-derived predictions and empirical MEG data. The postevent suppressive mechanism explains an array of studies that associate beta with decreased processing, whereas the during-event facilitatory mechanism may demand a reinterpretation of the role of beta events in the context of coincident timing.


Assuntos
Percepção do Tato , Biofísica , Humanos , Magnetoencefalografia , Córtex Somatossensorial/fisiologia , Tato/fisiologia , Percepção do Tato/fisiologia
2.
Molecules ; 28(2)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36677864

RESUMO

Emulsion systems are widely used in various industries, including the cosmetic, pharmaceutical, and food industries, because they require emulsifiers to stabilize the inherently unstable contact between oil and water. Although emulsifiers are included in many products, excessive use of emulsifiers destroys skin barriers and causes contact dermatitis. Accordingly, the consumer demand for cosmetic products made from natural ingredients with biocompatibility and biodegradability has increased. Starch in the form of solid nanosized particles is considered an attractive emulsifier that forms and stabilizes Pickering emulsion. Chemical modification of nanosized starch via acid hydrolysis can effectively provide higher emulsion stability. However, typical acid hydrolysis limits the industrial application of starch due to its high time consumption and low recovery. In previous studies, the effects of starch nanoparticles (SNPs) prepared by treatment with acidic dry heat, which overcomes these limitations, on the formation and stability of Pickering emulsions were reported. In this study, we evaluated the safety of SNPs in skin cell lines, 3D cultured skin, and human skin. We found that the cytotoxicity of SNPs in both HaCaT cells and HDF cells could be controlled by neutralization. We also observed that SNPs did not induce structural abnormalities on 3D cultured skin and did not permeate across micropig skin tissue or human skin membranes. Furthermore, patches loaded with SNPs were found to belong in the "No irritation" category because they did not cause any irritation when placed on human skin. Overall, the study results suggest that SNPs can be used as a safe emulsifier in various industries, including in cosmetics.


Assuntos
Nanopartículas , Pele Artificial , Humanos , Emulsões/química , Amido/química , Emulsificantes/química , Nanopartículas/química , Tamanho da Partícula
3.
J Am Chem Soc ; 144(33): 15185-15192, 2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-35948416

RESUMO

Selective oxidation to synthesize nitriles is critical for feedstock manufacturing in the chemical industry. Current strategies typically involve substitutions of alkyl halides with toxic cyanides or the use of strong oxidation reagents (oxygen or peroxide) under ammoxidation/oxidation conditions, setting considerable challenges in energy efficiency, sustainability, and production safety. Herein, we demonstrate a facile, green, and safe electrocatalytic route for selective oxidation of amines to nitriles under ambient conditions, assisted by the anodic water oxidation on metal-doped α-Ni(OH)2 (a typical oxygen evolution reaction catalyst). By controlling the balance between co-adsorption of the amine molecule and hydroxyls on the catalyst surface, we demonstrate that Mn doping significantly promotes the subsequent chemical oxidation of amines, resulting in Faradaic efficiencies of 96% for nitriles under ≥99% conversion. This anodic oxidation is further coupled with cathodic hydrogen evolution for overall atomic economy and additional green energy production.

4.
Small ; 18(45): e2204797, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36123143

RESUMO

Interface modulation of nickel phosphide (Ni2 P) to produce an optimal catalytic activation barrier has been considered a promising approach to enhance the hydrogen production activity via water splitting. Herein, heteronuclei-mediated in situ growth of hollow Ni2 P nanospheres on a surface defect-engineered titanium carbide (Ti3 C2 Tx ) MXene showing high electrochemical activity for the hydrogen evolution reaction (HER) is demonstrated. The heteronucleation drives intrinsic strain in hexagonal Ni2 P with an observable distortion at the Ni2 P@Ti3 C2 Tx MXene heterointerface, which leads to charge redistribution and improved charge transfer at the interface between the two components. The strain at the Ni2 P@Ti3 C2 Tx MXene heterointerface significantly boosts the electrochemical catalytic activities and stability toward HER in an acidic medium via a combination between experimental results and theoretical calculations. In a 0.5 m H2 SO4 electrolyte, the Ni2 P@Ti3 C2 Tx MXene hybrid shows excellent HER catalytic performance, requiring an overpotential of 123.6 mV to achieve 10 mA cm-2 with a Tafel slope of 39 mV dec-1 and impressive durability over 24 h operation. This approach presents a significant potential to rationally design advanced catalysts coupled with 2D materials and transition metal-based compounds for state-of-the-art high efficiency energy conversions.

5.
Bioorg Chem ; 122: 105716, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35303621

RESUMO

The discovery of small molecules that regulate specific neuronal phenotypes is important for the development of new therapeutic candidates for neurological diseases. Estrogen-related receptor γ (ERRγ), an orphan nuclear receptor widely expressed in the central nervous system (CNS), is closely related to the regulation of neuronal metabolism and differentiation. We previously reported that upregulation of ERRγ could enhance dopaminergic neuronal phenotypes in the neuroblastoma cell line, SH-SY5Y. In this study, we designed and synthesized a series of new ERRγ agonists using the X-ray crystal structure of the GSK4716-bound ERRγ complex and known synthetic ligands. Our new ERRγ agonists exhibited increased transcriptional activities of ERRγ. In addition, our molecular docking results supported the experimental findings for ERRγ agonistic activity of the potent analogue, 5d. Importantly, 5d not only enhanced the expression of dopaminergic neuronal-specific molecules, TH and DAT but also activated the relevant signaling events, such as the CREB-mediated signaling pathway. The results of the present study may provide useful clues for the development of novel ERRγ agonists for neurological diseases related to the dopaminergic nervous system.


Assuntos
Neurônios Dopaminérgicos , Receptores de Estrogênio , Neurônios Dopaminérgicos/metabolismo , Simulação de Acoplamento Molecular , Fenótipo , Receptores de Estrogênio/metabolismo , Regulação para Cima
6.
Bioorg Chem ; 116: 105398, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34628222

RESUMO

The first total syntheses of isocorniculatolide B, corniculatolide B, and corniculatolide C, consisting of isomeric corniculatolide skeletons, have been accomplished in a divergent manner. The key features of the synthesis involve the construction of diaryl ether linkages by nucleophilic aromatic substitution, installation of a C14-substituted alkyl side chain via a sequence of Baeyer-Villiger reaction and Claisen rearrangement, and efficient construction of corniculatolide and isocorniculatolide frameworks, including 17-membered (exterior) macrolactone skeletons from a versatile diaryl ether intermediate by Mitsunobu macrolactonization. Moreover, we prepared the structural congeners of isomeric corniculatolides via diverted total synthesis approach including desmethyl analogues and related dimeric macrolides. The anti-inflammatory activities of the synthesized natural products, analogues and synthetic intermediates were also investigated. In particular, corniculatolide B significantly inhibited the protein expression of COX-2 and the mRNA expressions of TNF-α, IL-1ß and IL-6 by inhibiting of NF-κB signaling in intestinal epithelial cells induced by lipopolysaccharide treatment. It also significantly inhibited the promoter activity and the phosphorylation of subunits p50 and p65 of NF-κB to the same extent as Bay 11-7082, a potent IκB kinase inhibitor. These results suggest that corniculatolide B might have therapeutic potential in inflammatory bowel disease via NF-κB signaling pathway.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Lactonas/farmacologia , Macrolídeos/farmacologia , NF-kappa B/antagonistas & inibidores , Animais , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Linhagem Celular , Relação Dose-Resposta a Droga , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Lactonas/síntese química , Macrolídeos/síntese química , Estrutura Molecular , NF-kappa B/metabolismo , Ratos , Relação Estrutura-Atividade
7.
Proc Natl Acad Sci U S A ; 115(23): 5872-5877, 2018 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-29784794

RESUMO

The oxygen evolution reaction (OER) is critical to solar production of fuels, but the reaction mechanism underlying the performance for a best OER catalyst, Fe-doped NiOOH [(Ni,Fe)OOH], remains highly controversial. We used grand canonical quantum mechanics to predict the OER mechanisms including kinetics and thus overpotentials as a function of Fe content in (Ni,Fe)OOH catalysts. We find that density functional theory (DFT) without exact exchange predicts that addition of Fe does not reduce the overpotential much. However, DFT with exact exchange predicts dramatic improvement in performance for (Ni,Fe)OOH, leading to an overpotential of 0.42 V and a Tafel slope of 23 mV/decade (dec), in good agreement with experiments, 0.3-0.4 V and 30 mV/dec. We reveal that the high spin [Formula: see text] Fe(IV) leads to efficient formation of an active O radical intermediate, while the closed shell [Formula: see text] Ni(IV) catalyzes the subsequent O-O coupling, and thus it is the synergy between Fe and Ni that delivers the optimal performance for OER.

8.
Angew Chem Int Ed Engl ; 60(30): 16448-16456, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-33973312

RESUMO

Motivated by in silico predictions that Co, Rh, and Ir dopants would lead to low overpotentials to improve OER activity of Ni-based hydroxides, we report here an experimental confirmation on the altered OER activities for a series of metals (Mo, W, Fe, Ru, Co, Rh, Ir) doped into γ-NiOOH. The in situ electrical conductivity for metal doped γ-NiOOH correlates well with the trend in enhanced OER activities. Density functional theory (DFT) calculations were used to rationalize the in situ conductivity of the key intermediate states of metal doped γ-NiOOH during OER. The simultaneous increase of OER activity with intermediate conductivity was later rationalized by their intrinsic connections to the double exchange (DE) interaction between adjacent metal ions with various d orbital occupancies, serving as an indicator for the key metal-oxo radical character, and an effective descriptor for the mechanistic evaluation and theoretical guidance in design and screening of efficient OER catalysts.

9.
Molecules ; 25(9)2020 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-32397326

RESUMO

Despite numerous reports on the beneficial effects of catechin or epicatechin contained in tea and cacao extract on human health, a conclusive and precise molecular mechanism has not been elucidated. Metabolism of chemical compounds in gut microbiota recently gained significant attention, and extensive studies have been devoted in this field. In conjunction with these results, our group focused on the anti-inflammatory effects of both enantiomers of DHPV (5-(3',4'-dihydroxyphenyl)-γ-valerolactone), produced in the intestine by microbiota metabolism, on IEC-6 cells. Divergent and efficient enantioselective synthesis of (S)- and (R)-DHPV was efficiently achieved by cross-metathesis and Sharpless asymmetric dihydroxylation as a key reaction for four steps in 16% and 14% overall yields, respectively. The anti-inflammatory effects of two enantiomers were tested on IEC-6 cells, and we found that (S)-DHPV was more active than (R)-DHPV. This result implicates that the metabolite produced in the gut has beneficial effects on IEC-6 cells of rat intestines, and the chirality of the metabolite is important for its anti-inflammatory activity. This also provided information for the future discovery of novel small molecular therapeutics for the treatment of inflammatory bowel disease.


Assuntos
Anti-Inflamatórios , Doenças Inflamatórias Intestinais/tratamento farmacológico , Mucosa Intestinal/metabolismo , Animais , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Linhagem Celular , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/patologia , Lactonas/síntese química , Lactonas/química , Lactonas/farmacologia , Ratos
10.
Graefes Arch Clin Exp Ophthalmol ; 257(12): 2717-2721, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31512042

RESUMO

BACKGROUND: Previous studies have reported the association of HK2 and NCK2 genes with normal-tension glaucoma (NTG) in Japan, but there has been no follow-up study in other countries, so the relevance of these genes to NTG appears uncertain at present. Thus, we investigated the relationship between the HK2 and NCK2 genes and NTG in a Korean NTG cohort. METHODS: In total, 154 unrelated Korean patients with NTG and 101 normal Korean controls were recruited. Thus, a total of 255 participants were analyzed for NCK2 (rs2033008) and HK2 (rs678350) gene polymorphisms. RESULTS: The minor allele frequency (MAF) of rs678350 was significantly higher in NTG patients (MAF = 0.32) than in controls (MAF = 0.23) (OR, 1.586; 95% CI, 1.058 to 2.375; P = 0.028). This trend was more significant in the dominant model (OR, 1.908; 95% CI, 1.144 to 3.180; P = 0.015). When we performed logistic regression analysis to adjust for age, both the allelic and dominant models were still statistically significant. No significant difference was observed in rs2033008 allele or genotype frequencies between the NTG patients and control subjects. CONCLUSIONS: The current study suggested that HK2 gene polymorphism may contribute to the genetic susceptibility to NTG.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , DNA/genética , Predisposição Genética para Doença , Hexoquinase/genética , Pressão Intraocular/fisiologia , Glaucoma de Baixa Tensão/genética , Proteínas Oncogênicas/genética , Polimorfismo de Nucleotídeo Único , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Idoso , Alelos , Feminino , Frequência do Gene , Genótipo , Hexoquinase/metabolismo , Humanos , Incidência , Glaucoma de Baixa Tensão/epidemiologia , Glaucoma de Baixa Tensão/metabolismo , Masculino , Pessoa de Meia-Idade , Proteínas Oncogênicas/metabolismo , República da Coreia/epidemiologia
11.
J Craniofac Surg ; 30(7): 2181-2183, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31283641

RESUMO

PURPOSE: To report long-term surgical outcomes of Cutler-Beard reconstructive surgery in patients with large full-thickness upper eyelid defects following malignant tumor excision. METHODS: The medical records of 5 consecutive patients with full-thickness upper eyelid defects following tumor resection who underwent Cutler-Beard surgery were reviewed retrospectively between April 2005 and November 2018. Surgical procedure comprises 2 stages: first, complete tumor resection followed by bridged full-thickness lower eyelid advancement flap; second, separation of the closed eyelid with eyelid margin repair 7 to 9 weeks later. Postoperative anatomical, functional and cosmetic outcomes, and complications were evaluated during follow-up at 22 to 77 months. RESULTS: Patients were in the age group of 49 to 75 years, including 3 (60%) females and 2 (40%) males. Three of the 5 patients (60%) exhibited sebaceous cell carcinoma and 2 (40%) showed squamous cell carcinoma. Three patients (60%) underwent Cutler-Beard surgery after recurrence of primary carcinoma following previous operation. Three patients underwent revision surgery with entropion, 2 underwent correction for wound dehiscence and 1 was treated with symblepharon lysis. No serious or permanent ocular complications were observed during the operation or follow-up with the patients. The procedure resulted in good aesthetic quality and acceptable sequelae at the donor site. CONCLUSIONS: Cutler-Beard procedure for the reconstruction of large and full-thickness upper eyelid defects is an effective procedure with satisfactory long-term results, although a few patients may require minor revision surgery.


Assuntos
Doenças Palpebrais/cirurgia , Adenocarcinoma Sebáceo/cirurgia , Idoso , Blefaroplastia/métodos , Carcinoma de Células Escamosas/cirurgia , Estudos de Viabilidade , Feminino , Cabelo , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/cirurgia , Procedimentos de Cirurgia Plástica , Estudos Retrospectivos , Couro Cabeludo/cirurgia , Neoplasias das Glândulas Sebáceas/cirurgia , Retalhos Cirúrgicos/cirurgia , Doadores de Tecidos
12.
Nano Lett ; 18(4): 2450-2458, 2018 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-29578723

RESUMO

Bimetallic PtNi nanoparticles have been considered as a promising electrocatalyst for oxygen reduction reaction (ORR) in polymer electrolyte membrane fuel cells (PEMFCs) owing to their high catalytic activity. However, under typical fuel cell operating conditions, Ni atoms easily dissolve into the electrolyte, resulting in degradation of the catalyst and the membrane-electrode assembly (MEA). Here, we report gallium-doped PtNi octahedral nanoparticles on a carbon support (Ga-PtNi/C). The Ga-PtNi/C shows high ORR activity, marking an 11.7-fold improvement in the mass activity (1.24 A mgPt-1) and a 17.3-fold improvement in the specific activity (2.53 mA cm-2) compared to the commercial Pt/C (0.106 A mgPt-1 and 0.146 mA cm-2). Density functional theory calculations demonstrate that addition of Ga to octahedral PtNi can cause an increase in the oxygen intermediate binding energy, leading to the enhanced catalytic activity toward ORR. In a voltage-cycling test, the Ga-PtNi/C exhibits superior stability to PtNi/C and the commercial Pt/C, maintaining the initial Ni concentration and octahedral shape of the nanoparticles. Single cell using the Ga-PtNi/C exhibits higher initial performance and durability than those using the PtNi/C and the commercial Pt/C. The majority of the Ga-PtNi nanoparticles well maintain the octahedral shape without agglomeration after the single cell durability test (30,000 cycles). This work demonstrates that the octahedral Ga-PtNi/C can be utilized as a highly active and durable ORR catalyst in practical fuel cell applications.

13.
J Am Chem Soc ; 140(22): 6745-6748, 2018 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-29749225

RESUMO

The oxygen evolution reaction (OER) is critical to efficient water splitting to produce the H2 fuel for sustainable energy production. Currently, the best non-noble metal OER electrocatalyst in base conditions is the Fe-doped NiOOH (Ni1- xFe xOOH), with an overpotential of η = 0.4, but much lower values are desired. We use density functional theory to determine the overall mechanism for the OER of Ni1- xFe xOOH, concluding that promoting radical character on the metal-oxo bond is critical to efficient OER. Then we consider replacing Fe with 17 other transition metals of the Fe, Ru, and Os rows, where we find 3 new promising candidates: Co, Rh, and Ir, which we estimate to have η = 0.27, 0.15, and 0.02, respectively, all very much improved performance compared to Fe, making all three systems excellent candidates for experimental testing.

14.
Somatosens Mot Res ; 35(1): 52-57, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29577788

RESUMO

The Barrels meeting annually brings together researchers focused on the rodent whisker to cortical barrel system prior to the Society for Neuroscience meeting. The 2017 meeting focused on the classification of cortical interneurons, the role interneurons have in shaping brain dynamics, and finally on the circuitry underlying oral sensations. The meeting highlighted the latest advancements in this rapidly advancing field.


Assuntos
Congressos como Assunto , Interneurônios/fisiologia , Córtex Somatossensorial/fisiologia , Vibrissas/fisiologia , Animais , Baltimore , Interneurônios/metabolismo , Córtex Somatossensorial/citologia , Córtex Somatossensorial/metabolismo , Vibrissas/metabolismo
15.
Phys Chem Chem Phys ; 18(10): 7035-41, 2016 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-26735140

RESUMO

The hydrogen (H) spillover phenomenon has attracted considerable attention in the catalysis field. Many researchers have focused on the phenomenon itself, as well as its applications for advanced catalytic systems. In particular, H spillover on non-reducible materials, such as alumina, silica, and zeolites, is a controversial issue owing to the lack of understanding regarding its mechanistic properties. In this study, we use density functional theory calculations to propose the entire mechanism of H spillover from H2 activation on a platinum to its participation in chemical reactions on the external surface of a zeolite. We determined that surface hydroxyl groups of the zeolites, such as Brønsted acid sites, play a role in initiating H spillover, and the Lewis acid sites facilitate the entire process by allowing H to be transferred as a H(+)/e(-) charge pair, as well as providing good binding sites for organic reactants. Theoretical results explain the key experimental features, and we expect that this work will help to elucidate the H spillover phenomenon on non-reducible support materials and to utilize it for catalytic systems.

16.
Angew Chem Int Ed Engl ; 55(32): 9297-300, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27352078

RESUMO

Electrocatalytic CO2 conversion into fuel is a prospective strategy for the sustainable energy production. However, still many parts of the catalyst such as low catalytic activity, selectivity, and stability are challenging. Herein, a hierarchical hexagonal Zn catalyst showed highly efficient and, more importantly, stable performance as an electrocatalyst for selectively producing CO. Moreover, we found that its high selectivity for CO is attributed to morphology. In electrochemical analysis, Zn (101) facet is favorable to CO formation whereas Zn (002) facet favors the H2 evolution during CO2 electrolysis. Indeed, DFT calculations showed that (101) facet lowers a reduction potential for CO2 to CO by more effectively stabilizing a (.) COOH intermediate than (002) facet. This further suggests that tuning the crystal structure to control (101)/(002) facet ratio of Zn can be considered as a key design principle to achieve a desirable product from Zn catalyst.

17.
J Am Chem Soc ; 136(32): 11355-61, 2014 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-25061918

RESUMO

CO2 conversion is an essential technology to develop a sustainable carbon economy for the present and the future. Many studies have focused extensively on the electrochemical conversion of CO2 into various useful chemicals. However, there is not yet a solution of sufficiently high enough efficiency and stability to demonstrate practical applicability. In this work, we use first-principles-based high-throughput screening to propose silver-based catalysts for efficient electrochemical reduction of CO2 to CO while decreasing the overpotential by 0.4-0.5 V. We discovered the covalency-aided electrochemical reaction (CAER) mechanism in which p-block dopants have a major effect on the modulating reaction energetics by imposing partial covalency into the metal catalysts, thereby enhancing their catalytic activity well beyond modulations arising from d-block dopants. In particular, sulfur or arsenic doping can effectively minimize the overpotential with good structural and electrochemical stability. We expect this work to provide useful insights to guide the development of a feasible strategy to overcome the limitations of current technology for electrochemical CO2 conversion.

18.
J Am Chem Soc ; 136(25): 9070-7, 2014 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-24905892

RESUMO

N-doped carbon materials are considered as next-generation oxygen reduction reaction (ORR) catalysts for fuel cells due to their prolonged stability and low cost. However, the underlying mechanism of these catalysts has been only insufficiently identified, preventing the rational design of high-performing catalysts. Here, we show that the first electron is transferred into O2 molecules at the outer Helmholtz plane (ET-OHP) over a long range. This is in sharp contrast to the conventional belief that O2 adsorption must precede the ET step and thus that the active site must possess as good an O2 binding character as that which occurs on metallic catalysts. Based on the ET-OHP mechanism, the location of the electrode potential dominantly characterizes the ORR activity. Accordingly, we demonstrate that the electrode potential can be elevated by reducing the graphene size and/or including metal impurities, thereby enhancing the ORR activity, which can be transferred into single-cell operations with superior stability.

19.
Ophthalmology ; 121(1): 93-99, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23962652

RESUMO

OBJECTIVE: To determine whether the ganglion cell-inner plexiform layer (GCIPL) or circumpapillary retinal nerve fiber layer (cpRNFL) is better at distinguishing eyes with early glaucoma from normal eyes on the basis of the the initial location of the visual field (VF) damage. DESIGN: Retrospective, observational study. PARTICIPANTS: Eighty-four patients with early glaucoma and 43 normal subjects were enrolled. The patients with glaucoma were subdivided into 2 groups according to the location of VF damage: (1) an isolated parafoveal scotoma (PFS, N = 42) within 12 points of a central 10 degrees in 1 hemifield or (2) an isolated peripheral nasal step (PNS, N = 42) within the nasal periphery outside 10 degrees of fixation in 1 hemifield. METHODS: All patients underwent macular and optic disc scanning using Cirrus high-definition optical coherence tomography (Carl Zeiss Meditec, Dublin, CA). The GCIPL and cpRNFL thicknesses were compared between groups. Areas under the receiver operating characteristic curves (AUCs) were calculated. MAIN OUTCOME MEASURES: Comparison of diagnostic ability using AUCs. RESULTS: The average and minimum GCIPL of the PFS group were significantly thinner than those of the PNS group, whereas there was no significant difference in the average retinal nerve fiber layer (RNFL) thickness between the 2 groups. The AUCs of the average (0.962) and minimum GCIPL (0.973) thicknesses did not differ from that of the average RNFL thickness (0.972) for discriminating glaucomatous changes between normal and all glaucoma eyes (P =0.566 and 0.974, respectively). In the PFS group, the AUCs of the average (0.988) and minimum GCIPL (0.999) thicknesses were greater than that of the average RNFL thickness (0.961, P =0.307 and 0.125, respectively). However, the AUCs of the average (0.936) and minimum GCIPL (0.947) thicknesses were lower than that of the average RNFL thickness (0.984) in the PNS group (P =0.032 and 0.069, respectively). CONCLUSIONS: The GCIPL parameters were more valuable than the cpRNFL parameters for detecting glaucoma in eyes with parafoveal VF loss, and the cpRNFL parameters were better than the GCIPL parameters for detecting glaucoma in eyes with peripheral VF loss. Clinicians should know that the diagnostic capability of macular GCIPL parameters depends largely on the location of the VF loss.


Assuntos
Glaucoma/diagnóstico , Fibras Nervosas/patologia , Disco Óptico/patologia , Doenças do Nervo Óptico/diagnóstico , Células Ganglionares da Retina/patologia , Escotoma/diagnóstico , Campos Visuais , Área Sob a Curva , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , Tomografia de Coerência Óptica , Acuidade Visual/fisiologia
20.
Ophthalmology ; 121(10): 1990-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24935284

RESUMO

PURPOSE: To compare the initial visual field (VF) defect pattern and the spectral-domain optical coherence tomography (OCT) parameters and investigate the effects of distinct types of optic disc damage on the diagnostic performance of these OCT parameters in early glaucoma. DESIGN: Retrospective, observational study. PARTICIPANTS: A total of 138 control eyes and 160 eyes with early glaucoma were enrolled. The glaucomatous eyes were subdivided into 4 groups according to the type of optic disc damage: focal ischemic (FI) group, myopic (MY) group, senile sclerotic (SS) group, and generalized enlargement (GE) group. METHODS: The values of total deviation (TD) maps were analyzed, and superior-inferior (S-I) differences of TD were calculated. The optic nerve head (ONH) parameters, peripapillary retinal nerve fiber layer (pRNFL), and ganglion cell-inner plexiform layer (GCIPL) thicknesses were measured. MAIN OUTCOME MEASURES: Comparison of diagnostic ability using area under the receiver operating characteristic curves (AUCs). RESULTS: The S-I and central S-I difference of the FI group were larger than those of the GE group. The rim area of the SS group was larger than those of the 3 other groups, and the vertical cup-to-disc ratio (CDR) of the GE group was larger than that of the MY group. In addition, the minimum and inferotemporal GCIPL thicknesses of the FI group were smaller than those of the GE group. The AUC of the rim area (0.89) was lower than that of the minimum GCIPL (0.99) in the SS group, and the AUC of the vertical CDR (0.90) was lower than that of the minimum GCIPL (0.99) in the MY group. Furthermore, the AUCs of the minimum GCIPL thicknesses of the FI and MY group were greater than those of the average pRNFL thickness for detecting glaucoma, as opposed to the SS and GE. CONCLUSIONS: The OCT parameters differed among the 4 groups on the basis of the distinct optic disc appearance and initial glaucomatous damage pattern. Clinicians should be aware that the diagnostic capability of OCT parameters could differ according to the type of optic disc damage in early glaucoma.


Assuntos
Glaucoma/diagnóstico , Disco Óptico/patologia , Tomografia de Coerência Óptica/normas , Adulto , Idoso , Área Sob a Curva , Estudos de Casos e Controles , Estudos Transversais , Diagnóstico Precoce , Feminino , Glaucoma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Campos Visuais
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