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1.
Inorg Chem ; 2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38943619

RESUMEN

A novel organo sulfur and selenium-controlled emission behavior in discrete copper(I) clusters has been demonstrated for the first time. The pentanuclear [Cu5Br5(L1)2] (1), trinuclear [Cu3Br3(L2)2] (2), dinuclear [Cu2I2(L1)2] (3), and tetranuclear [Cu4I4(L2)2CH3CN] (4) copper(I) discrete clusters have been synthesized from the reaction between L1 [L1 = 1-isopropyl-3-(pyridin-2-yl)-imidazol-2-thione] or L2 [L2 = 1-isopropyl-3-(pyridin-2-yl)-imidazol-2-selone] chelating ligands and corresponding copper(I) halide salts. These new clusters have been characterized by FT-IR, UV-visible, thermogravimetric analysis, and fluorescence spectroscopy techniques. Single-crystal X-ray diffraction studies reveal that 1-4 consists of abundant d10-d10 interactions. The structural and bonding features of clusters have been investigated using density functional theory calculations. Notably, the L2-ligated 2 and 4 are poorly emissive, while L1-ligated 1 and 3 showed strong emission in the orange and green regions, respectively. The time-dependent density functional theory natural transition orbital calculations of 1 and 3 reveal the nature of the transitions contributed by 3MLCT/3LLCT/3ILCT. Photoluminescence quantum yields of 1 and 3 are 19 and 11%, with average lifetimes of 21.55 and 6.57 µs, respectively. 1 and 3 were coated on prototype LED bulbs for light-emitting performance.

2.
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.

3.
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.

4.
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.

5.
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.

6.
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.

7.
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.

8.
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
9.
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.

10.
Reprod Med Biol ; 14: 5-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25620883

RESUMEN

PURPOSE: To compare the embryo outcomes of in vitro fertilization/intra-cytoplasmic sperm injection with a gonadotropin-releasing hormone (GnRH) antagonist protocol with follicle stimulating hormone (FSH) and with human menopausal gonadotropin (hMG). METHODS: We performed a retrospective cohort study in 465 patients. Stimulation was started by daily FSH injection, and either FSH was continued (FSH alone group) or hMG was administrated (FSH-hMG group) after administration of a GnRH antagonist. Primary outcomes were the embryo profile (number of retrieved, mature, and fertilized eggs, and morphologically good embryos on day 3) and endocrine profile. Secondary outcomes were the doses and durations of gonadotropin. Data were stratified by the patients' age into two groups: <35 years and ≥35 years. RESULTS: In patients aged <35 years, the number of retrieved oocytes in the FSH alone group was significantly increased than that in the FSH-hMG group (13.7 vs 9.2, P = 0.04), while there was no difference at other age groups. The FSH-hMG group required a significantly greater amount of gonadotropins at any age (all ages, P < 0.001; <35 years, P = 0.013; ≥35 years, P < 0.001). CONCLUSIONS: Exogenous FSH alone is probably sufficient for follicular development and hMG may not improve the embryo profile in a GnRH antagonist protocol across all age.

11.
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.

13.
BMC Med Ethics ; 13: 9, 2012 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-22607034

RESUMEN

BACKGROUND: Previous studies have found that the decision-making process for stored unused frozen embryos involves much emotional burden influenced by socio-cultural factors. This study aims to ascertain how Japanese patients make a decision on the fate of their frozen embryos: whether to continue storage discard or donate to research. METHODS: Ten Japanese women who continued storage, 5 who discarded and 16 who donated to research were recruited from our infertility clinic. Tape-recorded interviews were transcribed and analyzed for emergent themes. RESULTS: A model of patients' decision-making processes for the fate of frozen embryos was developed, with a common emergent theme, "coming to terms with infertility" resulting in either acceptance or postponing acceptance of their infertility. The model consisted of 5 steps: 1) the embryo-transfer moratorium was sustained, 2) the "Mottainai"- embryo and having another child were considered; 3) cost reasonability was taken into account; 4) partner's opinion was confirmed to finally decide whether to continue or discontinue storage. Those discontinuing, then contemplated 5): the effect of donation. Great emotional conflict was expressed in the theme, steps 2, 4, and 5. CONCLUSIONS: Patients' 5 step decision-making process for the fate of frozen embryos was profoundly affected by various Japanese cultural values and moral standards. At the end of their decision, patients used culturally inherent values and standards to come to terms with their infertility. While there is much philosophical discussion on the moral status of the embryo worldwide, this study, with actual views of patients who own them, will make a significant contribution to empirical ethics from the practical viewpoint.


Asunto(s)
Pueblo Asiatico , Criopreservación , Características Culturales , Toma de Decisiones , Destinación del Embrión , Investigaciones con Embriones , Infertilidad , Obligaciones Morales , Parejas Sexuales , Adulto , Pueblo Asiatico/psicología , Pueblo Asiatico/estadística & datos numéricos , Conflicto Psicológico , Criopreservación/economía , Toma de Decisiones/ética , Emociones , Femenino , Humanos , Infertilidad/psicología , Japón , Masculino , Investigación Cualitativa , Encuestas y Cuestionarios
14.
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.

15.
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.

16.
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.

17.
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.

18.
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.

19.
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.

20.
Endocrinology ; 150(1): 350-6, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18787030

RESUMEN

IL-1, secreted by human embryos and trophoblast cells, is important for successful implantation and pregnancy. We previously reported that IL-1beta induced IL-8 production in human endometrial stromal cells (ESCs) and that induction was regulated by substances implicated in implantation. In the present study using human primary cells in culture, we measured IL-1beta-induced production of IL-8 from endometrial epithelial cells (EECs) and ESCs and examined effects of the endometrium-derived IL-8 on migration and number of first-trimester villous cytotrophoblast cells (vCTs). Both basal and IL-1beta-induced IL-8 levels of cell supernatants were much higher in EECs than ESCs. Addition of IL-1beta to EECs increased the chemotactic activity of the supernatants to vCTs, and this effect was suppressed by immunoneutralization with anti-IL-8 antibody. Supernatants of IL-1beta-stimulated EECs yielded significantly higher number of vCTs compared with those of untreated EECs, and the effect was inhibited by IL-8 antibody. These findings suggest that IL-1 promotes implantation by stimulating EECs to produce IL-8, which subsequently induces migration of vCTs and contributes to survival of vCTs.


Asunto(s)
Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Endometrio/fisiología , Células Epiteliales/fisiología , Interleucina-1beta/farmacología , Interleucina-9/fisiología , Primer Trimestre del Embarazo , Adulto , Técnicas de Cultivo de Célula , Endometrio/citología , Endometrio/efectos de los fármacos , Células Epiteliales/citología , Células Epiteliales/efectos de los fármacos , Femenino , Humanos , Interleucina-8/farmacología , Persona de Mediana Edad , Embarazo
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