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1.
Molecules ; 28(23)2023 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-38067509

RESUMEN

Micro-sized chiral-nematic liquid crystal (N* LC) polymer particles have attracted considerable interest as versatile reflective colorants with selective circularly polarized light (CPL) properties. However, challenges in achieving the desired size distribution of N* LC particles have led to an incomplete understanding of their reflective characteristics. In this study, we successfully synthesized N* LC particles via dispersion polymerization, enabling precise control over size polydispersity by manipulating the composition of the polymerization solvent. Our investigation revealed that monodisperse N* LC particles displayed distinct reflection bands with high CPL selectivity, while polydisperse particles exhibited broader reflection with lower CPL selectivity. These findings underscore the potential to synthesize N* LC particles with tailored reflective properties using identical monomeric compounds. Furthermore, we demonstrated the production of multifunctional reflective colorants by blending N* LC particles with varying reflection colors. These discoveries hold significant promise for advancing the development of reflective colorants and anti-counterfeiting printing techniques utilizing micro-sized N* LC particles.

2.
DEN Open ; 3(1): e181, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36310664

RESUMEN

A 36-year-old woman visited our hospital with a chief complaint of bleeding during defecation. Colonoscopy revealed a 20-mm pedunculated polyp in the sigmoid colon, which was en bloc resected under endoscopy. The histopathological diagnosis was adenoma cancer with a depth of invasion indicating mucosal cancer, no lymphovascular invasion, and negative at the resection margin. The poorly differentiated adenocarcinoma component comprised approximately 5% of the tumor. Although there were no recurrence signs in the computed tomography scans obtained 4 months post polypectomy, the patient experienced aggressive lower back pain at 6 months post polypectomy. Local recurrence, peritoneal dissemination, and liver metastasis were confirmed. Finally, the patient died following a rapid and aggressive deterioration of her general condition. Histological examination of the local recurrence revealed a poorly differentiated adenocarcinoma (por2), with immunostaining revealing a high Ki67 positivity rate of 95%. Moreover, the poorly differentiated adenocarcinoma region of the resected polyp had a Ki67 positivity rate of 90%, which suggested that they were the same tumors. These findings suggested that the recurrence could have occurred through implantation.

3.
ACS Omega ; 7(17): 15016-15026, 2022 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-35557695

RESUMEN

Heterocyclic compounds with effective solid-state luminescence offer a wide range of uses. It has been observed that combining pyrimidine and indole moieties in a single molecule can enhance material behavior dramatically. Here, different heterocyclic compounds with indole and pyrimidine moieties have been synthesized effectively, and their structures have been validated using NMR, IR, and mass spectroscopy. The photoluminescence behavior of two substances was investigated in powder form and solutions of varying concentrations. After aggregation, one molecule displayed a redshifted luminescence spectrum, whereas another homolog showed a blueshift. Thus, density functional theory calculations were carried out to establish that introducing a terminal group allows modifying of the luminescence behavior by altering the molecular packing. Because of the non-planarity, intermolecular interactions, and tiny intermolecular distances within the dimers, the materials demonstrated a good emission quantum yield (Φem) in the solid state (ex. 25.6%). At high temperatures, the compounds also demonstrated a stable emission characteristic.

4.
Reprod Med Biol ; 21(1): e12459, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35431648

RESUMEN

Purpose: Our aim is to make an ideal embryo culture medium close to human oviduct fluid (HOF) components, and to evaluate the quality of this medium with embryo quality and clinical outcomes in assisted reproductive technology (ART) by a prospective randomized controlled trial (RCT). Methods: Study I: HOF was collected laparoscopically from patients (n = 28) with normal pelvic findings. According to HOF analysis results, the new medium "HiGROW OVIT®" (OVIT) was designed. Study II: Embryos (2 pronuclei (2PN) = 9633) were assigned from 1435 patients. The blastulation rate (BR), good BR (gBR), utilized (transferred/cryo-preserved) BR (uBR), pregnancy rate (PR), and miscarriage rate (MR) were compared between the OVIT and control groups by RCT. Results: The novel medium 'OVIT' was produced according to 31 HOF components. The concentrations of essential amino acids (e-AAs) were lower in OVIT than in current media, yet the opposite was true for ne-AA concentrations. gBR and uBR were higher in the OVIT group than in the control group. In the older female group, gBT and uBR were significantly higher in the OVIT group. Conclusions: The novel medium 'OVIT' was produced according to HOF data. The OVIT had significantly better embryo quality and clinical outcomes than the current media.

5.
Chem Asian J ; 17(11): e202200225, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35434893

RESUMEN

Hexaazatriphenylene (HAT) derivatives have attracted wide attention because of their electron-deficient nature and unique self-assembly properties. In this work, a facile synthesis method for obtaining HAT derivatives with alternating electron-withdrawing nitrile and electron-donating alkoxy groups (HATCNOCn) is proposed. Crystal structure analysis indicated that HATCNOCn forms a one-dimensional columnar structure via strong π-π interactions. Density functional theory calculations revealed that the edge of HATCNOCn is divided into positively and negatively charged sites owing to the presence of alternating nitrile and alkoxy groups, which would induce strong π-π interactions. Thermal analysis and polarizing optical microscopy revealed that HATCNOCn exhibits columnar liquid-crystal phases. Time-resolved microwave conductivity measurements further demonstrated the photoconductive nature of HATCNOCn. The proposed strategy could provide a new strategy for the design of novel organic semiconductive materials.

6.
Molecules ; 26(23)2021 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-34885836

RESUMEN

Gold(I) complexes, enabling to form linear coordination geometry, are promising materials for manifesting both aggregation-induced emission (AIE) behavior due to strong intermolecular Au-Au (aurophilic) interactions and liquid crystalline (LC) nature depending on molecular geometry. In this study, we synthesized several gold(I) complexes with rod-like molecular skeletons where we employed a mesogenic biphenylethynyl ligand and an isocyanide ligand with flexible alkoxyl or alkyl chains. The AIE behavior and LC nature were investigated experimentally and computationally. All synthesized gold(I) complexes exhibited AIE properties and, in crystal, room-temperature phosphorescence (RTP) with a relatively high quantum yields of greater than 23% even in air. We have demonstrated that such strong RTP are drastically changed depending on the crystal-size and/or crystal growth process that changes quality of crystals as well as the aggregate structure, of e.g., Au-Au distance. Moreover, the complex with longer flexible chains showed LC nature where RTP can be observed. We expect these rod-like gold(I) complexes to have great potential in AIE-active LC phosphorescent applications such as linearly/circularly polarizing phosphorescence materials.

7.
Dalton Trans ; 50(45): 16514-16518, 2021 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-34761758

RESUMEN

A mesoionic N-heterocyclic carbene-gold(I) complex with a unique Au⋯H-C(methine) intramolecular hydrogen bonding interaction has been investigated in the solid state. The structure of this new neutral gold(I)-carbene was characterized by FT-IR and NMR spectroscopy, TGA, and X-ray diffraction techniques. Density functional theory (DFT) and atoms-in-molecule (AIM) analysis revealed that the gold-hydrogen bonding situation is more favored. Besides, the photophysical properties of the gold(I) complex were also investigated.

8.
Molecules ; 26(20)2021 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-34684774

RESUMEN

Chiral nematic (N*) liquid crystal elastomers (LCEs) are suitable for fabricating stimuli-responsive materials. As crosslinkers considerably affect the N*LCE network, we investigated the effects of crosslinking units on the physical properties of N*LCEs. The N*LCEs were synthesized with different types of crosslinkers, and the relationship between the N*LC polymeric system and the crosslinking unit was investigated. The N*LCEs emit color by selective reflection, in which the color changes in response to mechanical deformation. The LC-type crosslinker decreases the helical twisting power of the N*LCE by increasing the total molar ratio of the mesogenic compound. The N*LCE exhibits mechano-responsive color changes by coupling the N*LC orientation and the polymer network, where the N*LCEs exhibit different degrees of pitch variation depending on the crosslinker. Moreover, the LC-type crosslinker increases the Young's modulus of N*LCEs, and the long methylene chains increase the breaking strain. An analysis of experimental results verified the effect of the crosslinkers, providing a design rationale for N*LCE materials in mechano-optical sensor applications.

9.
Reprod Med Biol ; 20(2): 123-132, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33850445

RESUMEN

PURPOSE: This study was conducted to investigate how the COVID-19 pandemic has impacted reproductive medical providers' behaviors and considerations, including their concerns regarding the necessity of fertility treatments. METHODS: A web-based questionnaire was distributed to Japan Society of Fertilization and Implantation (JSFI) members from May 18 through May 31, 2020 to survey their professional behaviors and concerns during the COVID-19 pandemic. RESULTS: Most survey participants reported a decrease in the number of patients and a decrease in their workload. Most also believe that the use of fertility treatments will return to the pre-pandemic levels after the COVID-19 pandemic ends. Additionally, more than half of the participants reported that they consider fertility treatment neither necessary nor unnecessary during the COVID-19 pandemic. CONCLUSIONS: At the institute where reproductive medical providers worked in Japan, the number of outpatients and the working time tended to decrease during the COVID-19 pandemic. However, amid fears of infection during the COVID-19 pandemic, the reproductive medical providers working at fertility institutes in Japan have remained engaged in their work with a sense of mission and hope.

10.
Chem Asian J ; 16(5): 521-529, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33442961

RESUMEN

The synthesis and the luminescence features of three gold(I)-N-heterocyclic carbene (NHC) complexes are presented to study how the n-alkyl group can influence the luminescence properties in the crystalline state. The mononuclear gold(I)-NHC complexes, [(L1 )Au(Cl)] (1), [(L2 )Au(Cl)] (2), and [(L3 )Au(Cl)] (3) were isolated from the reactions between [(tht)AuCl] and corresponding NHC ligand precursors, [N-(9-acridinyl)-N'-(n-butyl)-imidazolium chloride, (L1 .HCl)], [N-(9-acridinyl)-N'-(n-pentyl)-imidazolium chloride, (L2 .HCl)] and [N-(9-acridinyl)-N'-(n-hexyl)-imidazolium chloride, (L3 .HCl)]. Their single-crystal X-ray analysis reveals the influence of the n-alkyl groups on solid-state packing. A comparison of the luminescence features of 1-3 with n-alkyl substituents is explored. The molecules 1-3 depicted blue emission in the solution state, while the yellow emission (for 1), greenish-yellow emission (for 2), and blue emission (for 3) in the crystalline phase. This paradigm emission shift arises from n-butyl to n-pentyl and n-hexyl in the crystalline state due to the carbon-carbon rotation of the n-alkyl group, which tends to promote unusual solid packing. Hence n-alkyl group adds a novel emission property in the crystalline state. Density Functional Theory and Time-Dependent Density Functional Theory calculations were carried out for monomeric complex, N-(9-acridinyl)-N'-(n-heptyl)imidazole-2-ylidene gold(I) chloride and dimeric complex, N-(9-acridinyl)-N'-(n-heptyl)imidazole-2-ylidene gold(I) chloride to understand the structural and electronic properties.

11.
ACS Omega ; 5(46): 29988-30000, 2020 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-33251435

RESUMEN

Biocompatible luminogens with aggregation-induced emission (AIE) have several applications in the biology field, such as in detecting biomacromolecules bioprobes and in bio-imaging. Due to their bioactivities and light-emitting properties, many heterocyclic compounds are good candidates for such applications. However, heterocyclic π-conjugated systems with AIE behavior remain rare as strong intermolecular π-π interactions usually quench their emission. In this work, new thienopyrimidine heterocyclic compounds were synthesized and their structures were verified by elemental analysis and Fourier transform infrared (FT-IR), 1H nuclear magnetic resonance (NMR), and 13C NMR spectra. The photophysical properties of some compounds were investigated in the solution and solid states. Density functional theory calculations were also performed to confirm the observed photophysical properties of the compounds. The studied dyes displayed AIE properties with spectral shapes related to the aggregate structure and a quantum yield up to 10.8%. The emission efficiency of the powder is attributed to the incorporation of multiply rotatable and twisted aryl groups to the fused heterocyclic moieties. The dyes also showed high thermal stability and potent antimicrobial activities against numerous bacterial and fungal strains. Additionally, the cytotoxicity of the new compounds was evaluated against the Caco-2 cell line, and molecular docking was used to investigate the binding conformation of the most effective compound with the MNK2 enzyme. Therefore, the presented structures may potentially be used for bioapplications.

12.
Reprod Med Biol ; 19(4): 350-356, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33071636

RESUMEN

PURPOSE: The purpose of this study was to investigate the effectiveness of intrauterine administration of platelet-rich plasma (PRP) in frozen embryo transfer (FET) cycle in Japanese patients with a thin endometrium. METHOD: A prospective single-arm self-controlled trial was conducted in Japan. PRP administration was performed in 36 of the 39 eligible patients with a thin endometrium (≤7 mm). Hormone replacement therapy (HRT) with estrogen was performed for 2 menstrual cycles, and PRP was administrated on the 10th and 12th days of the second HRT cycle. The endometrial thickness was evaluated on transvaginal ultrasonography by two physicians at every visit, one an attending physician and the other a specialist physician blinded to the date and timing of the sonography. FET was performed during the second HRT cycle after PRP administration. RESULTS: After PRP administration, the mean (SD) endometrial thickness on the 14th day was significantly increased by 1.27 mm (P < .001) and 0.72 mm (P = .001) on the basis of the unblinded and blinded measurements, respectively. Of the 36 patients, 32 (88.9%) underwent FET. The clinical pregnancy rate was 15.6%. No adverse events occurred. CONCLUSIONS: PRP therapy was safe and effective in increasing endometrial thickness improving possibly pregnancy rate.

13.
Commun Chem ; 3(1): 139, 2020 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-36703373

RESUMEN

The aggregation behaviour of Au(I) complexes in condensed phases can affect their emission properties. Herein, aggregation-induced room-temperature phosphorescence (RTP) is observed from the crystals of trinuclear Au(I) complexes. The RTP is highly sensitive to the crystal structure, with a slight difference in the alkyl side chains causing not only a change in the crystal structure but also a shift in the RTP maximum. Furthermore, in nanocrystals, reversible RTP colour changes are induced by phase transitions between crystal polymorphs during crystal growth from solution or the pulverisation of bulk crystals. The colour change mechanism is discussed in terms of intermolecular interactions in the crystal structure of the luminescent aggregates. The results suggest that the behaviour in nanocrystals may differ from that in bulk crystals. These insights will advance the fundamental understanding of crystallisation mechanisms and may aid in the discovery of new materials properties for solids with nano- to micrometre sizes.

14.
RSC Adv ; 9(26): 14841-14848, 2019 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-35516307

RESUMEN

The synthesis and photophysical properties of macrocyclic Zn(ii) selone molecule have been reported. The structural property of Zn(ii) selone was elucidated using single crystal X-ray diffraction study. The solid-state structure of zinc(ii) selone molecule exhibits a perfect zinc(ii) selone 28 membered ring system with tetra coordination geometry around zinc(ii) center. The zinc(ii) selone ring system can be considered as the largest zinc(ii) ring system known without any non-interacting centered guest moiety. Detailed trends in photophysical as well as thermal properties were probed. In photoluminescence study, the solid-state sample of zinc(ii) selone ring system emits the bluish-yellow color with considerable quantum yields, while the solution state sample of zinc(ii) selone ring system in DMSO emits bluish-yellow. The luminescence lifetime of zinc(ii) selone was measured using standard time-correlated single photon counting (TCSPC) technique.

15.
RSC Adv ; 9(13): 7543-7550, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35519949

RESUMEN

Herein, the photophysical properties of an acridine derivative of a bis-N-heterocyclic carbene silver complex were investigated. The HOMO and LUMO energy differences between 9-[(N-methyl imidazol-2-ylidene)]acridine and 4,5-bis[(N-methyl-imidazol-2-ylidene)methyl]acridine were theoretically compared. Based on the calculation, the 4,5-bis N-heterocyclic carbene-tethered acridine type of ligand was found to be a potential source for tuning the fluorescent nature of the resultant metal derivatives. Thus, a 4,5-bis N-heterocyclic carbene (NHC)-tethered acridine silver(i) salt was synthesized, and its photophysical properties were investigated. The 4,5-bis[(N-isopropylimidazol-2-ylidene)methyl]acridine silver(i) hexafluorophosphate complex was obtained from the reaction between [4,5-bis{(N-isopropylimidazolium)methyl}acridine] hexafluorophosphate and Ag2O in very good yield; this molecule was characterized by elemental analysis and FTIR, multinuclear (1H and 13C) NMR, UV-Vis, and fluorescence spectroscopic techniques. The molecular structure has been confirmed by single-crystal X-ray diffraction analysis, which has revealed that the complex is a homoleptic mononuclear silver(i) cationic solid. The charge of the Ag(i)-NHC cation is balanced by the hexafluorophosphate anion. The cationic moieties are closely packed in the chair and inverted chair forms where silver(i) possesses a quasi-linear geometry. Moreover, the silver complex provided blue emission from all the three excitations with good fluorescence quantum yield. The fluorescence lifetime of the silver(i) complex has been determined using the time-correlated single photon counting technique. Interestingly, the fluorescence decay pattern and the fluorescence lifetimes of the silver complex are largely different from those of the parent ligand acridine imidazolium salt. Moreover, the theoretical predictions have been found to be in good agreement with the experimental results.

16.
Molecules ; 24(24)2019 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-31888246

RESUMEN

Highly efficient (≈75% quantum yield), aggregation-induced phosphorescence is reported. The phosphorescence is emitted at room temperature and in the presence of air from crystals of trinuclear Au(I) complexes, accompanied by an extremely large Stokes shift of 2.2 × 104 cm-1 (450 nm). The mechanism of the aggregation-induced room-temperature phosphorescence from the Au complex crystals was investigated in terms of the crystal packing structure and the primary structure of the molecules. It was found that two kinds of intermolecular interactions occurred in the crystals, and that these multiple dual-mode intermolecular interactions in the crystals play a crucial role in the in-air room-temperature phosphorescence of the trinuclear Au(I) complexes.


Asunto(s)
Oro/química , Luminiscencia , Temperatura , Cristalografía por Rayos X , Modelos Moleculares , Conformación Molecular , Procesos Fotoquímicos
17.
Sci Rep ; 8(1): 2380, 2018 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-29402920

RESUMEN

The epigenetic status of the genome changes dynamically from fertilization to implantation. In addition, the physiological environment during the process of gametogenesis, including parental age, may affect the epigenome of the embryo after fertilization. It is important to clarify the influence of parental age on gene expression in the embryo in terms of transgenerational epigenetics to improve the techniques currently used in assisted reproductive medicine. Here, we performed single-embryo RNA-seq analysis on human blastocysts fertilized by intracytoplasmic sperm injection, including from relatively elderly mothers, to elucidate the effects of parental age on the embryonic gene expression profile. We identified a number of genes in which the expression levels were decreased with increasing maternal age. Among these genes, several are considered to be important for meiotic chromosomal segregation, such as PTTG1, AURKC, SMC1B and MEIKIN. Furthermore, the expression levels of certain genes critical for autophagy and embryonic growth, specifically GABARAPL1 and GABARAPL3, were negatively correlated with advanced paternal age. In addition, levels of transcripts derived from major satellite repeats also decreased as the maternal age increased. These results suggest that epigenetic modifications of the oocyte genome may change with parental age and be transmitted to the next generation.


Asunto(s)
Blastocisto , Padres , Transcriptoma , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis de Secuencia de ARN
19.
Faraday Discuss ; 196: 269-283, 2017 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-27900378

RESUMEN

Mesogenic Au complexes with a biphenyl core were synthesized as new AIEgens, and their thermodynamic and photophysical properties were discussed. Similar to Au complexes with a phenyl core which have been reported previously, the complexes with a short alkoxy chain formed dimers in the crystal form. However, the complexes with a long alkoxy chain formed two-dimensional layer structures through multiple intermolecular interactions in both the crystalline and liquid-crystalline (LC) phases. The present Au complexes showed a high thermochemical stability against thermal decomposition and a high thermodynamic stability of the LC phase. Moreover, these materials exhibited intensive phosphorescence with a large quantum yield (∼66%) in the crystals. In the crystal and LC phase with a layer structure, the phosphorescence intensity was enhanced only on aggregation. Thus, these mesogenic Au complexes can be expected to be useful as phosphorescent AIEgens.

20.
Sci Rep ; 5: 7934, 2015 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-25879782

RESUMEN

A series of new cyclic trinuclear Au(I) complexes with alkoxy side chains of various lengths were synthesized as photoluminescence materials. None of the complexes emitted luminescence in solution; however, some showed photoluminescence in the crystalline phase. Single crystal X-ray structural analyses revealed that an intermolecular interaction between two Au atoms (aurophilic interaction) existed only in the emissive complexes, which formed molecular aggregates in the crystal. Because isolated molecules show no luminescence in the present system, we conclude that only molecules aggregated via aurophilic interactions can luminesce. We demonstrated that luminescence properties, such as colour and intensity, were very sensitive to the aggregated structure of the molecules. We also found that such luminescence properties can be controlled by a change in the aggregated structure induced by external stimuli, such as heat, solvent, and mechanical stress.

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