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1.
Chempluschem ; : e202300748, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38329154

RESUMO

Solubility enhancement is a key issue for developing the perylene diimide-based functional materials. Introduction of curved structure proved an effective solubilizing method without employing steric repulsion. In this work, wavily curved perylene diimides were developed as a new family of highly soluble curved perylene diimides. Moreover, their conformational dynamics, aggregating properties, electronic properties, and photovoltaic performances were thoroughly examined in comparison to the previously reported isomer exhibiting an arched curvature. The waved isomer demonstrated heightened rigidity and a greater propensity for aggregation compared to the arched isomer, likely attributed to its more planar structure. Each benzoxepin unit played a role in cancelling out the curvature on the opposite side. While the difference in the molecular curvature did not cause significant alterations in the photophysical and electron-accepting properties, we identified that the modulation of the curved structure is effective in controlling the morphology of the photoelectric conversion layer.

2.
Nat Commun ; 14(1): 5494, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37730676

RESUMO

Among the three primary colors, blue emission in organic light-emitting diodes (OLEDs) are highly important but very difficult to develop. OLEDs have already been commercialized; however, blue OLEDs have the problem of requiring a high applied voltage due to the high-energy of blue emission. Herein, an ultralow voltage turn-on at 1.47 V for blue emission with a peak wavelength at 462 nm (2.68 eV) is demonstrated in an OLED device with a typical blue-fluorescent emitter that is widely utilized in a commercial display. This OLED reaches 100 cd/m2, which is equivalent to the luminance of a typical commercial display, at 1.97 V. Blue emission from the OLED is achieved by the selective excitation of the low-energy triplet states at a low applied voltage by using the charge transfer (CT) state as a precursor and triplet-triplet annihilation, which forms one emissive singlet from two triplet excitons.

3.
J Org Chem ; 88(17): 12776-12782, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37614008

RESUMO

In this study, we propose heavy-metal-free reductive coupling of arylacetylenes with benzothiazole sulfones. The reactions of alkyl or benzylic benzothiazole sulfones with arylacetylenes are successfully performed in the presence of Hantzsch esters and K2CO3 under visible-light irradiation to afford 1,2-disubstituted alkenes in moderate to good yields, with Z-isomer as the major product. The utility of this protocol is expanded to α-deuterative coupling using a deuterated Hantzsch ester, furnishing the corresponding alkenes with high deuterium incorporation.

4.
Asia Ocean J Nucl Med Biol ; 11(1): 13-22, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36619192

RESUMO

Objectives: In the treatment of castration-resistant prostate cancer (CRPC) with bone metastases, radium-223 dichloride (Ra-223) is the only bone-targeted drug that shows survival benefits. Completing six courses of Ra-223 treatment is thought to be associated with better patient survival, but this treatment has a relatively high rate of acute adverse events. Methods: This retrospective study included 85 patients from 12 institutions in Japan to investigate the clinical significance of the completion of Ra-223 treatment and acute adverse events in CRPC patients. Results: Six courses of Ra-223 treatment were completed in 65.9% of the patients. Grade 3 or higher acute adverse events were observed in 27.1% of patients. The prostate specific antigen and alkaline phosphatase declined at 26.9% and 87.9%, respectively. The overall survival rates at 12 and 24 months were 80.7% and 63.2%, respectively. Both completion of six courses of Ra-223 treatment and absence of grade 3 or higher acute adverse events were associated with longer overall survival. In univariate analysis, factors related to the history of treatment (five or more hormone therapy agents and cytotoxic chemotherapy) and hematological parameters (Prostate specific antigen (PSA) doubling time, alkaline phosphatase, hemoglobin, albumin, and serum calcium) were associated with completing six courses of Ra-223 treatment without experiencing grade 3 or higher acute adverse events. Multivariate analysis showed that a history of chemotherapy, PSA doubling time, hemoglobin, and serum calcium showed statistical significance. We built a predictive score by these four factors. Patients with lower scores showed higher rates of treatment success (p<0.001) and longer overall survival (p<0.001) with statistical significance. Conclusions: Accomplishing six courses of Ra-223 treatment without grade 3 or higher acute adverse events was a prognostic factor in patients with mCRPC treated with Ra-223. We built a predictive score of treatment success and need future external validation.

5.
Neural Netw ; 155: 224-241, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36081196

RESUMO

Visual properties that primarily attract bottom-up attention are collectively referred to as saliency. In this study, to understand the neural activity involved in top-down and bottom-up visual attention, we aim to prepare pairs of natural and unnatural images with common saliency. For this purpose, we propose an image transformation method based on deep neural networks that can generate new images while maintaining the consistent feature map, in particular the saliency map. This is an ill-posed problem because the transformation from an image to its corresponding feature map could be many-to-one, and in our particular case, the various images would share the same saliency map. Although stochastic image generation has the potential to solve such ill-posed problems, the most existing methods focus on adding diversity of the overall style/touch information while maintaining the naturalness of the generated images. To this end, we developed a new image transformation method that incorporates higher-dimensional latent variables so that the generated images appear unnatural with less context information but retain a high diversity of local image structures. Although such high-dimensional latent spaces are prone to collapse, we proposed a new regularization based on Kullback-Leibler divergence to avoid collapsing the latent distribution. We also conducted human experiments using our newly prepared natural and corresponding unnatural images to measure overt eye movements and functional magnetic resonance imaging, and found that those images induced distinctive neural activities related to top-down and bottom-up attentional processing.


Assuntos
Aprendizado Profundo , Humanos , Redes Neurais de Computação , Imageamento por Ressonância Magnética
6.
Chemistry ; 27(56): 14081-14091, 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34355450

RESUMO

The influence of N-substituents on the photovoltaic properties of singly bay-linked perylene diimides (diPDIs) was systematically investigated to understand the aromatic-aliphatic balance, which is beneficial for achieving high device performance in organic photovoltaic (OPV) systems. The synthesis of various N-substituted diPDIs was successfully achieved using a newly developed one-step procedure, resulting in sufficiently high yields. Detailed investigations of seven variants of diPDIs demonstrated that the primary alkyl substituents, particularly the 2-ethylhexyl group, induce the self-organized growth of thin films with high crystallinity. This is beneficial for enhancing the device performance of bulk heterojunction (BHJ) systems. The results presented herein reveal the important roles of alkyl side chains as hydrophobic solubilizing auxiliaries or primary determinants in the control of the active layer nanomorphology. This offers a valuable guideline that is essential for developing high-performance organic semiconductor materials for future practical applications.

7.
Chemistry ; 27(35): 8951-8955, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-33851483

RESUMO

5,11-Diazadibenzo[hi,qr]tetracene was synthesized as a new nitrogen-substituted polycyclic heteroaromatic compound by Pd-catalyzed cycloisomerization of an alkyne precursor followed by oxidative cyclization with bis(trifluoroacetoxy)iodobenzene. The substitution of imine-type nitrogen atoms significantly enhanced its electron-accepting character and facilitated the direct nucleophilic addition of arylamines under strongly basic conditions to afford the desired amino-substituted products. The introduction of amino groups induced a remarkable red-shift in their absorption spectra; the tetrasubstituted product exhibited intense near-infrared absorbing property. Furthermore, the π-electronic system, which includes a redox-active 1,4-diazabutadiene moiety, underwent reversible interconversion to its corresponding reduced form upon reduction with NaBH4 and aerobic oxidation.

8.
Transl Lung Cancer Res ; 10(2): 712-722, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33718016

RESUMO

BACKGROUND: The optimal regimen for concurrent chemoradiotherapy (CCRT) of locally advanced non-squamous non-small cell lung cancer (NSCLC) was not definitive. We conducted randomized phase II study, NJLCG0601, and chemoradiotherapy with uracil/tegafur (UFT) and cisplatin achieved promising efficacy without severe toxicities. Here, we evaluated between this regimen and pemetrexed plus cisplatin in chemoradiotherapy for stage III non-squamous NSCLC. METHODS: Patients with inoperable stage III non-squamous NSCLC were randomly assigned in a 1:1 ratio to UFT 400 mg/m2 on days 1-14 and 29-42, and cisplatin 80 mg/m2 on days 8 and 36 (UP), or cisplatin 75 mg/m2 and pemetrexed 500 mg/m2 on days 1, 22, and 43 (PP). Involved-field radiotherapy (IFRT) underwent from day 1 to a total dose of 66 Gy in 33 fractions. Consolidation chemotherapy after CCRT was prohibited for this study. The primary endpoint was defined as 2-year overall survival (OS). This trial was registered in the University Hospital Medical Information Network Clinical Trials Registry (UMIN000003948). RESULTS: From November 2010 to June 2017, 86 patients were entered from 11 institutions. Median follow-up was 54 months. Of the 85 eligible patients, the 2-year OS rate was 78.6% (95% CI, 62.8-88.3%) in UP and 85.5% (95% CI, 70.5-93.2%) in PP. Median PFS and OS was 12.3 and 64.2 months in UP, 26.2 months and not reached in PP, respectively. Grade 3/4 febrile neutropenia was more frequent in the UP group (14.0% vs. 2.0%). CONCLUSIONS: Both UP and PP with IFRT achieved the expected 2-year OS. PP engendered more favorable OS and PFS compared to UP in terms.

9.
Chem Asian J ; 16(6): 690-695, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33491273

RESUMO

Curved perylene diimides fused with seven-membered rings have been synthesized using a regioselective bay-functionalization method and Pd-catalyzed intramolecular C-H/C-Br coupling reaction. X-Ray analysis and temperature-dependent NMR spectroscopy revealed the curved molecular structure with a certain degree of conformational flexibility. The curved and expanded π-conjugation altered the electronic properties while retaining the intrinsic properties of the parent perylene diimide. Despite the absence of solubilizing N-substituents, the curved perylene diimides showed sufficient solubility for application in solution-processed organic photovoltaic devices. The devices showed superior performance with a power conversion efficiency of up to 2.76% due to suppressed charge recombination. Our detailed investigations suggest that the introduction of a curved structure enables the removal of the bulky N-substituents, which is an effective way to achieve a thin-film morphology suitable for photoelectric conversion.

10.
J Med Invest ; 67(3.4): 298-303, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33148905

RESUMO

 Introduction : Central venous catheter (CVC) use is essential for treating esophageal cancer. Peripherally inserted central catheters (PICC) are commonly used recently for improved patient comfort and safety. We compared centrally inserted central catheters (CICC) and PICC insertions and examined their safety. Methods : We retrospectively investigated complications at the catheter insertion and post-insertion for 199 patients' esophageal cancer treatment (CICC : 45, PICC : 154) from 2013 to 2018. In addition, we summarized the results of catheter tip culture. Results : No serious complications occurred at the catheter insertion in either group. The rate of complications at catheter insertion was 5.8% for PICC and 6.7% for CICC patients. Post-insertion complications were observed in 6.5% and 11.1% of patients with PICC and CICC, respectively, and this difference was not significant. The incidence of catheter-related blood stream infection (CRBSI) was significantly lower in PICC than CICC patients (0.3 vs. 1.8 / 1,000 catheter-days ; p = 0.029). Catheter-related thrombosis was observed in PICC : 0.5 and CICC : 0.6, and occlusion due to blood flow reversal was observed in PICC : 0.5 and CICC : 0.6. Conclusion : PICCs are safer and more effective than CICCs for the treatment of esophageal cancer, and reduce the incidence of CRBSI. We hope to standardize the insertion procedures, conventionalize techniques, and establish training systems. J. Med. Invest. 67 : 298-303, August, 2020.


Assuntos
Cateteres Venosos Centrais , Neoplasias Esofágicas/cirurgia , Idoso , Infecções Relacionadas a Cateter/epidemiologia , Cateterismo Venoso Central/efeitos adversos , Cateterismo Periférico/efeitos adversos , Cateteres Venosos Centrais/efeitos adversos , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Trombose/epidemiologia
11.
Kyobu Geka ; 73(5): 384-387, 2020 May.
Artigo em Japonês | MEDLINE | ID: mdl-32398398

RESUMO

A 65-year-old man was referred to our hospital because of an abnormal shadow on a chest radiogram. Swelling of the face and upper limbs were noted. Enhanced computed tomography showed a 62×101 mm mass in the anterior mediastinum with invasion to the superior vena cava (SVC) and the right upper lobe of the lung. Surgical resection through a sternotomy was performed. The mediastinal tumor was resected along with the left brachiocephalic vein, the part of SVC wall and the partial right upper lobe of the lung with a clamp on the proximal SVC, followed by a left brachiocephalic vein reconstruction. There has been no evidence of recurrence after 1 year. This procedure may be an efficacious technical option in case of anterior mediastinal invasive tumor.


Assuntos
Veias Braquiocefálicas , Neoplasias do Mediastino , Idoso , Humanos , Masculino , Mediastino , Recidiva Local de Neoplasia , Veia Cava Superior
12.
Materials (Basel) ; 13(9)2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32384804

RESUMO

Perylene has had a tremendous impact in the history of material research for the molecular semiconductors. Among numerous derivatives of this polyaromatic hydrocarbon, perylene diimide (PDI) represents a promising class of organic materials envisioned as non-fullerene acceptors (NFAs) for the practical organic photovoltaic (OPV) applications due to their enhanced photo- and thermal stability and remarkably high electron affinity, some of which realize band-like transport properties. The present review guides some of the representative achievements in the development of rationally designed PDI systems, highlighting synthetic methodologies based on bay-functionalization strategies for creating well-designed molecular nanostructures and structure-performance relationship of perylene-based small molecular acceptors (SMAs) for the photovoltaic outcomes.

13.
Chempluschem ; 85(2): 285-293, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31967408

RESUMO

The development of an efficient synthetic protocol for multiply bay-functionalized perylenes and application of these products to photovoltaics are reported. Tetrabenzyl 1-(4-tert-butylphenoxy)perylene-3,4,9,10-tetracarboxylate underwent a regioselective bromination at the 7-position followed by a further bromination at the 12-position to provide a 7,12-dibromide in high 84% yield. This compound was transformed into a tetrasubstituted C2h -symmetric dibromide by a controlled monoetherification and a final bromination. The synthetic versatility of the new brominated precursors was demonstrated by their application to cross-coupling reactions, cyanation, and derivatization to the corresponding perylene diimide (PDI). Owing to the high solubility and the raised LUMO level, the obtained tetrasubstituted PDI showed significant advantages as an acceptor material for photovoltaic applications, exhibiting a remarkably high open-circuit voltage (VOC ) reaching 1.00 V. The observed high VOC could be understood by reduction of energy offset for charge separation and non-radiative recombination loss.

14.
Case Rep Oncol ; 12(2): 671-680, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31572157

RESUMO

Conversion surgery has been reported but few cases have undergone surgical R0 resection after second-line chemotherapy. We report a case of an unresectable locally advanced gastric cancer in a patient who finally underwent the operation (R0) after second-line chemotherapy. The 77-year-old male was diagnosed with gastric cancer (cT4 [SI; Skin, Liver] N0M0 c Stage IIIA) with invasion to the skin of the abdominal wall, and chemotherapy was initially performed because of his poor performance status and due to the large defect in the abdominal wall that might occur if an operation was performed. Partial response (PR) was observed after S-1+CDDP (SP) therapy, which was then stopped after which progressive disease (PD) was observed. Ramucirumab+Paclitaxel (RAM/PTX) therapy was chosen as second-line therapy, and PR was obtained again, following which total gastrectomy was performed (D2 dissection of lymph nodes, Roux-en-Y reconstruction, and combined resection of the partial skin and the affected region of the liver). At 30 months postoperatively, no recurrence has occurred and the patient is alive after the operation without chemotherapy.

15.
Langmuir ; 35(30): 9740-9746, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31272152

RESUMO

We have developed a new photon upconversion (UC) system utilizing a new amphiphilic sensitizer 1a that comprises a hydrophilic ruthenium complex and a lipophilic bisanthracene appendage. At concentrations higher than 5 µM in toluene, the sensitizer 1a formed a reverse micellar assembly which facilitated the triplet sensitization of 9,10-diphenylanthracene (DPA) more efficiently than homogeneously dispersed solutions to enhance the UC efficiency up to 38.2%. The Stern-Volmer analyses revealed the stepwise triplet-triplet energy transfers (TTET): (1) intramicellar energy transfer from the ruthenium core to the bisanthracene surface and (2) diffusion-dependent energy transfer from the surface to DPA. On these bases, it can be assumed that the reverse micellar assemblies accelerate the former TTET process to enhance the UC efficiency.

16.
Chemistry ; 25(7): 1711-1715, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30537047

RESUMO

Oxidation of ß-to-ß directly linked and sulfur-bridged meso-amino NiII -porphyrin dimers with PbO2 gave helical tetrapyrrin (biliverdin analogue)-fused NiII -porphyrins. These ring cleaving reactions differ markedly from the previously reported oxidation of a ß-ß linked NiII -porphyrin dimer carrying one amino group, which gave an azepine-fused porphyrin dimer. The tetrapyrrin-fused NiII -porphyrins display intense NIR absorption bands at 1200-1400 nm and reversible redox processes because of the highly π-conjugated networks and rigid structures. These tetrapyrrin-fused NiII -porphyrins were separated to stable enantiomers, which showed clear Cotton effects in their CD spectra with Δϵ of 102 order.

17.
Chemistry ; 25(2): 521-525, 2019 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-30402895

RESUMO

An azepine-fused NiII -porphyrin dimer was synthesized by oxidative amination of ß-ß linked NiII -porphyrin dimer, and its N-aryl congener was synthesized by twofold Buchwald-Hartwig amination of ß-to-ß linked and dichlorinated NiII -porphyrin dimer. Oxidation of the NH congener gave neutral aminyl radical and nitrenium ion successively in a similar manner to the previously reported NH-bridged NiII -porphyrin dimer. Oxidation of the N-aryl congener afforded formal nitrenium dication in a single-step two-electron oxidation. Stable nitrenium dications that are isoelectronic to neutral trivalent boron compounds and tertiary carbocations are rare. The chemical stability of the nitrenium dication was improved by chlorine substitution at the most reactive ß-position. The structural, optical, magnetic, electrochemical properties of these compounds were fully characterized.

18.
Angew Chem Int Ed Engl ; 57(30): 9434-9438, 2018 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-29882340

RESUMO

Nitrenium ions, isoelectronic nitrogen counterparts of carbenes, are important intermediates in various biological and chemical processes. Herein we describe the first synthesis and characterization of a stable nitrenium ion without resonance stabilization by adjoining amino groups. Namely, a stable salt of a diporphyrinylnitrenium ion was synthesized by stepwise oxidation of the corresponding diporphyrinylamine through a stable aminyl radical. The nitrenium ion exhibits characteristic features such as a singlet ground state, enhanced double-bond character of the central C-N bonds, no reactivity toward water and methanol, and negative solvatochromic behavior.

19.
Chemistry ; 24(48): 12708-12715, 2018 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-29882368

RESUMO

Boron(III) meso-lithiosubporphyrin was prepared by bromine-lithium exchange of B-tolyl BIII meso-bromosubporphyrin with n-butyllithium at -98 °C. The resulting subporphyrinyllithium was treated with various electrophiles such as benzophenone, N,N-dimethylformamide, CO2 , chlorotrimethylsilane, N-fluorobenzenesulfonimide, and dimesitylboryl fluoride to give the corresponding meso-functionalized BIII subporphyrins. The nucleophile was also used to construct BIII subporphyrin dimers such as bis(BIII subporphyrinyl)ketone, bis(BIII subporphyrinyl)carbinol, and disilane-bridged BIII subporphyrin dimer. The structural, optical, and electrochemical properties of these meso-functionalized BIII subporphyrins were examined by UV/Vis absorption and fluorescence spectroscopy, electrochemical studies, and DFT calculations.

20.
Chemistry ; 24(25): 6530-6533, 2018 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-29536577

RESUMO

PtII -catalyzed cyclization of ß-to-ß ethynylene-bridged meso-amino NiII porphyrin dimer 4 followed by oxidation with PbO2 afforded 1,5-naphthyridine-fused porphyrin dimer 5 in good yield. This dimer possesses a redox-active 1,4-diazabutadiene linkage that is interconvertible with its reduced 1,2-diaminoethene linkage upon treatments with NaBH4 or PbO2 . The dimer 5 exhibits an intense NIR absorption and a narrow HOMO-LUMO gap with a remarkably low reduction potential mainly due to effective bonding interactions in the LUMO through the 1,4-diazabutadiene linkage. In contrast, the reduced dimer 7 is fairly electron-rich with high HOMO energy and shows a relatively large HOMO-LUMO gap compared to that of 5.

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