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2.
Am J Dermatopathol ; 43(11): 781-787, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33767067

RESUMO

ABSTRACT: Distinguishing porocarcinoma from squamous cell carcinoma (SCC) is clinically significant; however, differential diagnosis can often be challenging. This study sought to confirm the diagnostic utility of cytokeratin 19, c-KIT, BerEP4, GATA3, and NUTM1 immunohistochemistry in distinguishing porocarcinoma from SCC. Immunohistochemical analysis of cytokeratin 19, c-KIT, BerEP4, GATA3, and NUTM1 in 14 porocarcinomas and 22 SCCs was performed; the extents and intensities of expression of these markers were recorded. The statistical associations of the immunoexpression between porocarcinoma and SCC were analyzed using the Pearson χ2 test. Cytokeratin 19 was positive in 13 (92.9%) of 14 porocarcinomas, and for all the positive cases, staining was strong and evident in >20% of the tumor cells. By contrast, 9 (40.9%) of 22 SCCs expressed cytokeratin 19 (P = 0.0018), of which 6 showed extremely focal (≤10% of the tumor cells) expression. Of the 14 porocarcinomas, 11 (78.6%) cases showed c-KIT positivity, whereas only 3 of 22 SCCs (13.6%) expressed c-KIT focally (P = 0.0001). In addition, BerEP4 immunostaining differed between porocarcinomas and SCCs (57.1% vs. 9.1%, respectively; P = 0.0017). However, no significant difference between the groups was reported in terms of GATA3 expression (57.1% vs. 72.7%, respectively; P = 0.3336). NUTM1 was expressed in 4/14 (28.6%) porocarcinomas but not in the SCCs. Immunohistochemistry for cytokeratin 19, c-KIT, and BerEP4 could be helpful in distinguishing porocarcinomas from SCCs. In addition, NUTM1 immunoexpression is highly specific, although not sensitive, to porocarcinomas. GATA3 immunohistochemistry has no meaningful implications in the differential diagnosis of porocarcinoma and SCC.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/metabolismo , Porocarcinoma Écrino/diagnóstico , Porocarcinoma Écrino/metabolismo , Neoplasias das Glândulas Sudoríparas/diagnóstico , Neoplasias das Glândulas Sudoríparas/metabolismo , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Diagnóstico Diferencial , Feminino , Fator de Transcrição GATA3/metabolismo , Humanos , Imuno-Histoquímica , Queratina-19/metabolismo , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Proto-Oncogênicas c-kit/metabolismo
3.
ACS Appl Mater Interfaces ; 12(15): 17776-17782, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32204584

RESUMO

Research on tin-lead (SnPb) perovskite solar cells (PSCs) has gained popularity in recent years because of their low band gap, which could be applied to tandem solar cells. However, most of the work is based on inverted PSCs using PEDOT:PSS as the hole-transport layer as normal-structure PSCs show lower efficiency. In this work, the reason behind the low efficiency of normal-structure SnPb PSCs is elucidated and surface passivation has been tested as a method to overcome the problem. In the case of normal PSCs, at the interface between the titania layer and SnPb perovskite, there are many carrier traps observed originating from Ti-O-Sn bonds. In order to avoid the direct contact between titania and the SnPb perovskite layer, the titania surface is passivated with carboxylic acid C60 resulting in an efficiency increase from 5.14 to 7.91%. This will provide a direction of enhancing the efficiency of the normal-structure SnPb PSCs through heterojunction engineering.

4.
J Dermatol ; 47(4): 356-362, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31984569

RESUMO

Immune-related adverse events (irAE) were reported to be associated with better outcomes in various cancers treated with the immune checkpoint inhibitor nivolumab. Considering that their development depends on host immune activation, irAE may reflect antitumor response in mucosal melanoma (MM). This single-center retrospective study including patients with advanced MM receiving nivolumab monotherapy between August 2014 and September 2018 investigated whether the development of irAE was associated with clinical efficacy. The study patients were divided into those with and without irAE, and treatment efficacy and safety were evaluated. The study cohort of 27 patients included 20 (74%), six (22%) and one (4%) patient with primary MM in the head and neck, genitourinary and anorectal regions, respectively. The irAE onset was not significantly associated with the objective response rate in patients while it was significantly associated with the disease control rate. The median progression-free survival in patients with and without irAE was 301 and 63 days, respectively. The median overall survival (OS) in patients with and without irAE was 723 and 199 days, respectively. According to the timing of irAE onset, the OS was better in seven patients who developed irAE after 180 days than in nine patients who developed irAE within 180 days. Although 16 patients (59%) experienced any grade irAE, including three (11%) with grade 3 or more irAE, there were no treatment-related deaths. These results indicated that the development of irAE may correlate with improved survival in patients with MM treated with nivolumab monotherapy. Further studies are necessary to confirm these findings.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Inibidores de Checkpoint Imunológico/efeitos adversos , Melanoma/tratamento farmacológico , Mucosa/patologia , Nivolumabe/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/diagnóstico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/imunologia , Feminino , Humanos , Inibidores de Checkpoint Imunológico/administração & dosagem , Japão/epidemiologia , Masculino , Melanoma/imunologia , Melanoma/mortalidade , Melanoma/patologia , Pessoa de Meia-Idade , Mucosa/imunologia , Nivolumabe/administração & dosagem , Intervalo Livre de Progressão , Estudos Retrospectivos , Índice de Gravidade de Doença
5.
J Phys Chem Lett ; 10(17): 5277-5283, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31423786

RESUMO

Lead-free tin perovskite solar cells (PSCs) show the most promise to replace the more toxic lead-based perovskite solar cells. However, the efficiency is significantly less than that of lead-based PSCs as a result of low open-circuit voltage. This is due to the tendency of Sn2+ to oxidize into Sn4+ in the presence of air together with the formation of defects and traps caused by the fast crystallization of tin perovskite materials. Here, post-treatment of the tin perovskite layer with edamine Lewis base to suppress the recombination reaction in tin halide PSCs results in efficiencies higher than 10%, which is the highest reported efficiency to date for pure tin halide PSCs. The X-ray photoelectron spectroscopy data suggest that the recombination reaction originates from the nonstoichiometric Sn:I ratio rather than the Sn4+:Sn2+ ratio. The amine group in edamine bonded the undercoordinated tin, passivating the dangling bonds and defects, resulting in suppressed charge carrier recombination.

6.
Nano Lett ; 18(6): 3600-3607, 2018 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-29701473

RESUMO

Frequently observed high Voc loss in tin-lead mixed perovskite solar cells is considered to be one of the serious bottle-necks in spite of the high attainable Jsc due to wide wavelength photon harvesting. An amicable solution to minimize the Voc loss up to 0.50 V has been demonstrated by introducing an n-type interface with spike structure between the absorber and electron transport layer inspired by highly efficient Cu(In,Ga)Se2 solar cells. Introduction of a conduction band offset of ∼0.15 eV with a thin phenyl-C61-butyric acid methyl ester layer (∼25 nm) on the top of perovskite absorber resulted into improved Voc of 0.75 V leading to best power conversion efficiency of 17.6%. This enhancement is attributed to the facile charge flow at the interface owing to the reduction of interfacial traps and carrier recombination with spike structure as evidenced by time-resolved photoluminescence, nanosecond transient absorption, and electrochemical impedance spectroscopy measurements.

7.
Sci Rep ; 8(1): 2482, 2018 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-29410450

RESUMO

Perovskite solar cells based on series of inorganic cesium lead bromide and iodide mixture, CsPbBr3-xI x , where x varies between 0, 0.1, 0.2, and 0.3 molar ratio were synthesized by two step-sequential deposition at ambient condition to design the variations of wide band gap light absorbers. A device with high overall photoconversion efficiency of 3.98 % was obtained when small amount of iodide (CsPbBr2.9I0.1) was used as the perovskite and spiro-OMeTAD as the hole transport material (HTM). We investigated the origin of variation in open circuit voltage, Voc which was shown to be mainly dependent on two factors, which are the band gap of the perovskite and the work function of the HTM. An increment in Voc was observed for the device with larger perovskite band gap, while keeping the electron and hole extraction contacts the same. Besides, the usage of bilayer P3HT/MoO3 with deeper HOMO level as HTM instead of spiro-OMeTAD, thus increased the Voc from 1.16 V to 1.3 V for CsPbBr3 solar cell, although the photocurrent is lowered due to charge extraction issues. The stability studies confirmed that the addition of small amount of iodide into the CsPbBr3 is necessarily to stabilize the cell performance over time.

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