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1.
J Reprod Dev ; 69(4): 223-226, 2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37331813

RESUMO

Superovulation procedures are routinely and widely used in mouse reproductive technology. Previous studies have shown that a large number of oocytes can be obtained from adult mice (> 10 weeks old) using a combined treatment with progesterone (P4) and anti-inhibin serum (AIS). However, these effects have not been fully investigated in young (4 weeks) C57BL/6J mice. Here, we found that a modified superovulation protocol (combined treatment with P4, AIS, eCG (equine chorionic gonadotropin), and hCG (human chorionic gonadotropin); P4D2-Ae-h) improved the number of oocytes compared to the control (eCG and hCG) (39.7 vs. 21.3 oocytes/mouse). After in vitro fertilization, pronuclear formation rates were 69.3% (P4D2-Ae-h group) and 66.2% (control group). After embryo transfer, 46.4% (116/250) of the embryos in the P4D2-Ae-h group successfully developed to term, which was comparable to the control group (42.9%; 123/287 embryos). In conclusion, our protocol (P4D2-Ae-h) was effective for superovulation in young C57BL/6J mice.


Assuntos
Gonadotropinas Equinas , Inibinas , Oócitos , Progesterona , Animais , Feminino , Humanos , Camundongos , Gonadotropina Coriônica/farmacologia , Gonadotropinas Equinas/farmacologia , Cavalos , Inibinas/farmacologia , Camundongos Endogâmicos C57BL , Progesterona/farmacologia , Superovulação
2.
BMC Ophthalmol ; 22(1): 263, 2022 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-35690806

RESUMO

BACKGROUND: Positive dysphotopsia is a symptom caused by the reflection of incident light through the pupil at the inner surface of the intraocular lens (IOL) edge after cataract surgery and is perceived as an abnormal arcuate or radiating photopic image at night or indoors with a light source. Although positive dysphotopsia is one of the most important symptoms that affect patients after cataract surgery, it is still not well known even among ophthalmologists. Positive dysphotopsia as the cause of patient complaint following intraocular surgery other than cataract surgery has not been identified. CASE PRESENTATION: A 52-year-old man underwent IOL extraction and intrascleral IOL fixation for bilateral IOL subluxation at another hospital. The right eye had good subjective visibility, but the patient noticed symptoms of light sources appearing divided into multiple lights indoors after surgery in the left eye. Because the cause of the symptoms could not be identified, the patient visited our department. At the time of his first visit, the corrected visual acuity in both eyes was good, and ocular findings in eye position, motility, intraocular pressure, and fundus were within normal limits. The elongated holes of peripheral iridectomy (PI) created during previous intrascleral IOL fixation were observed to be approximately 2 mm in length on the nasal side in both eyes. The PI hole in the right eye was covered by the optics of the IOL, whereas the edge of the IOL overlapped the center of the PI hole in the left eye. Accordingly, we concluded that the abnormal photopic image in the left eye was caused by positive dysphotopsia, in which light passing through the PI hole was reflected by the edge of the IOL. We attempted surgical closure of the PI hole, resulting in the complete disappearance of positive dysphotopsia. CONCLUSIONS: A PI hole created during intrascleral IOL fixation may cause postoperative positive dysphotopsia depending on the position of the IOL edge. Thus, surgeons should be aware of the importance of the size and location of the PI hole when creating it during surgery.


Assuntos
Catarata , Lentes Intraoculares , Catarata/complicações , Humanos , Implante de Lente Intraocular/efeitos adversos , Implante de Lente Intraocular/métodos , Lentes Intraoculares/efeitos adversos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Transtornos da Visão/etiologia
3.
Sci Adv ; 5(1): eaau0637, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30613768

RESUMO

Few artificial systems can be exfoliated into, and observed as, single wires with lengths of more than several micrometers, and no previous example features a copolymer structure; this is in contrast with biopolymers such as single-strand DNAs. Here, we create a set of one-dimensional coordination copolymers featuring bis(dipyrrinato)zinc complex motifs in the main chain. A series of random copolymers is synthesized from two types of bridging dipyrrin proligand and zinc acetate, with various molar ratios between the proligands. Sonication of the bulk solid copolymer in organic solvent exfoliates single strands with lengths of 1.4 to 3.0 µm. Atomic force microscopy at ambient conditions visualizes the copolymer structure as height distributions. The copolymer structure improves its photoluminescence (up to 32%) relative to that of the corresponding homopolymers (3 and 10%). Numerical simulation based on a restricted random walk model reproduces the photoluminescence intensification, suggesting at the same time the existence of fast intrawire exciton hopping.

4.
J Org Chem ; 83(2): 690-702, 2018 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-29231717

RESUMO

The L-shaped, π-extended pentacycle dibenzopyrrolo[1,2-a][1,8]naphthyridine and its derivatives were synthesized using two methods: fully intramolecular [2 + 2 + 2] cycloaddition and oxidative aromatization using substituted carbodiimide and modification of an electron-rich indole ring of an L-shaped skeleton via electrophilic reaction and cross-coupling. These L-shaped compounds emitted fluorescence in high quantum yield. The position of substituents affected the fluorescence color through two different mechanisms, π-conjugation and skeletal distortion, which caused the substituted L-shaped compounds to emit fluorescence in a variety of colors and to exhibit solvato-fluorochromism.

5.
Chem Commun (Camb) ; 53(54): 7509-7512, 2017 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-28630966

RESUMO

Imine-linked BODIPY oligomers show fluorescence quantum yields of up to 0.93. The azine linker may mediate π-conjugation that extends over six BODIPY units with redshifts up to 125 nm. BODIPYs are immobilized on silica gel through heterogeneous imine-bond formation, being fluorescent and robust.

6.
Inorg Chem ; 56(7): 3909-3915, 2017 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-28294604

RESUMO

A paramagnetic, luminescent organometallic gold(I) complex AuI(C6F5)(PyBTM), where PyBTM is a photostable fluorescent polychlorinated diphenyl(4-pyridyl)methyl radical, was prepared, and its crystal and electronic structures and magnetic and optical properties were investigated. Magnetic studies using electron spin resonance spectroscopy and a superconducting quantum interference device magnetometer indicated the existence of S = 1/2 spin per molecule, with the spin density distributed mainly on the PyBTM ligand. The complex exhibited fluorescence in CHCl3 with emission peak wavelength (λem) of 619 nm and the absolute fluorescence quantum yield (ϕem) of 0.04, confirming that AuI(C6F5)(PyBTM) is the first luminescent organometallic complex with a coordinated luminescent radical. Solvent-dependent unique luminescent characteristics were observed in halogenated solvents (CCl4, CHCl3, CH2Cl2, and ClCH2CH2Cl). ϕem decreased, and λem shifted to longer wavelengths as the polarity (dielectric constant) of the solvent increased. Notably, the complex in CCl4 displayed fluorescence with ϕem = 0.23, which was quite high in radicals, while showed dual fluorescence in CH2Cl2 and ClCH2CH2Cl with lifetimes of around 1 and 7 ns for two emissive components. Density functional theory (DFT) and time-dependent (TD)-DFT calculations indicated that the fluorescence occurred from an interligand charge transfer (CT) excited state in CCl4, in which the C6F5 and PyBTM moieties acted as electron donor and acceptor, respectively, while the fluorescence was centered at the PyBTM ligand in the other three solvents. This method, i.e., the formation of an interligand CT state, to enhance ϕem is distinctly different from the methods reported previously. The present study revealed that a coordination bond is available for forming emissive CT excited states that lead to high ϕem, providing a novel method with greater capability for realizing highly emissive radicals.

7.
Inorg Chem ; 55(12): 5732-4, 2016 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-27267265

RESUMO

This Communication reports the first observation of solid-state photoluminescence in bis(dipyrrinato)zinc(II) complexes with various substituents. The report discusses the effect of their substituents on their crystal structures and spectroscopic properties. Their meso-aryl groups are revealed to play important roles in the spectroscopic properties in the solid state.

8.
J Am Chem Soc ; 138(17): 5666-77, 2016 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-27043441

RESUMO

Bis(dipyrrinato)metal(II) and tris(dipyrrinato)metal(III) complexes have been regarded as much less useful luminophores than their boron difluoride counterparts (4,4-difluoro-4-bora-3a,4a-diaza-s-indacenes, BODIPYs), especially in polar solvent. We proposed previously that dissymmetry in such metal complexes (i.e., two different dipyrrinato ligands in one molecule) improves their fluorescence quantum efficiencies. In this work, we demonstrate the universality and utility of our methodology by synthesizing eight new dissymmetric bis(dipyrrinato)zinc(II) complexes and comparing them with corresponding symmetric complexes. Single-crystal X-ray diffraction analysis, (1)H and (13)C NMR spectroscopy, and high-resolution mass spectrometry confirm the retention of dissymmetry in both solution and solid states. The dissymmetric complexes all show greater photoluminescence (PL) quantum yields (ϕPL) than the corresponding symmetric complexes, allowing red to near-infrared emissions with large pseudo-Stokes shifts. The best performance achieves a maximum PL wavelength of 671 nm, a pseudo-Stokes shift of 5400 cm(-1), and ϕPL of 0.62-0.72 in toluene (dielectric constant εs = 2.4), dichloromethane (εs = 9.1), acetone (εs = 21.4), and ethanol (εs = 24.3). The large pseudo-Stokes shift is distinctive considering BODIPYs with small Stokes shifts (∼500 cm(-1)), and the ϕPL values are higher than or comparable to those of BODIPYs fluorescing at similar wavelengths. Electrochemistry and density functional theory calculations illustrate that frontier orbital ordering in the dissymmetric complexes meets the condition for efficient PL proposed in our theory.

9.
Angew Chem Int Ed Engl ; 55(9): 3022-6, 2016 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-26822564

RESUMO

The development of disilane-bridged donor-acceptor-donor (D-Si-Si-A-Si-Si-D) and acceptor-donor-acceptor (A-Si-Si-D-Si-Si-A) compounds is described. Both types of compound showed strong emission (λem =ca. 500 and ca. 400 nm, respectively) in the solid state with high quantum yields (Φ: up to 0.85). Compound 4 exhibited aggregation-induced emission enhancement in solution. X-ray diffraction revealed that the crystal structures of 2, 4, and 12 had no intermolecular π-π interactions to suppress the nonradiative transition in the solid state.

10.
Angew Chem Int Ed Engl ; 55(4): 1377-81, 2016 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-26663591

RESUMO

Heteroleptic zinc(II) complexes synthesized using achiral dipyrrinato and chiral bis(oxazoline) ligands show bright fluorescence with quantum efficiencies of up to 0.70. The fluorescence originates from the (1)π-π* photoexcited state localized exclusively on the dipyrrinato ligand. Furthermore, the luminescence is circularly polarized despite the achirality of the dipyrrinato ligand. Single-crystal X-ray structure analysis discloses that the chiral bis(oxazoline) ligand undergoes intramolecular π-π stacking with the dipyrrinato ligand, inducing axial chirality in the dipyrrinato moiety.

11.
Nat Commun ; 6: 6713, 2015 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-25831973

RESUMO

Two-dimensional polymeric nanosheets have recently gained much attention, particularly top-down nanosheets such as graphene and metal chalcogenides originating from bulk-layered mother materials. Although molecule-based bottom-up nanosheets manufactured directly from molecular components can exhibit greater structural diversity than top-down nanosheets, the bottom-up nanosheets reported thus far lack useful functionalities. Here we show the design and synthesis of a bottom-up nanosheet featuring a photoactive bis(dipyrrinato)zinc(II) complex motif. A liquid/liquid interfacial synthesis between a three-way dipyrrin ligand and zinc(II) ions results in a multi-layer nanosheet, whereas an air/liquid interfacial reaction produces a single-layer or few-layer nanosheet with domain sizes of >10 µm on one side. The bis(dipyrrinato)zinc(II) metal complex nanosheet is easy to deposit on various substrates using the Langmuir-Schäfer process. The nanosheet deposited on a transparent SnO2 electrode functions as a photoanode in a photoelectric conversion system, and is thus the first photofunctional bottom-up nanosheet.

12.
Dalton Trans ; 44(34): 15103-6, 2015 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-25847680

RESUMO

Heteroleptic bis(dipyrrinato)copper(II) and nickel(II) complexes are synthesized. Their structures are determined by X-ray diffraction analysis, and their properties are investigated by using cyclic voltammetry, chronocoulometry, and UV/vis absorption spectroscopy.


Assuntos
Cobre/química , Níquel/química , Nitrogênio/química , Complexos de Coordenação/química , Cristalografia por Raios X , Eletroquímica , Luz , Metais/química , Cloreto de Metileno/química , Conformação Molecular , Compostos Orgânicos/química , Oxirredução , Oxigênio/química , Espectrofotometria Ultravioleta , Difração de Raios X
13.
Chem Sci ; 6(5): 2853-2858, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28706672

RESUMO

One-dimensional coordination polymers (1D-CPs) tend either to dissociate into constitutive ligands and metals readily in solution, or to aggregate randomly and amorphously, which prevents them from widespread application. In the present research, 1D-CPs comprising bridging dipyrrin ligands and divalent metal ions (Zn2+, Ni2+, and Cu2+) are synthesized. A liquid/liquid interfacial reaction gives rise to single crystals suitable for X-ray diffraction analysis: A dichloromethane solution of the ligand is layered with aqueous metal(ii) acetate, such that the coordination reaction proceeds at the liquid/liquid interface. Isolated single fibers of the zinc coordination polymer may be exfoliated from the single crystal or bulk solid upon ultrasonication. Atomic force microscopy (AFM) detects the isolated fibers with lengths of more than several µm. The exfoliated 1D-CP wires feature good processability, realizing a conjugate with single-wall carbon nanotubes (SWCNTs), and a thin film on a transparent SnO2 electrode. The processed materials show electric conversion ability: For example, the modified SnO2 electrode serves as a photoanode for a photoelectric conversion system. The designability and tunability of the present 1D-CPs is demonstrated by a ligand modification, affording a luminescent property and an extension of the photoelectric conversion response to longer wavelengths.

14.
Org Lett ; 16(12): 3212-5, 2014 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-24910923

RESUMO

Acid-responsive fluorescent compounds were prepared by introducing a nitrophenyl group to L-shaped pentacycles with a pyrrolo[1,2-a][1,8]naphthylidine backbone. These compounds show almost no fluorescence under neutral conditions, but emit green to orange fluorescence upon addition of trifluoroacetic acid. Acid titration experiments and NMR spectroscopy, plus DFT calculations, show that formation of a pyridinium cation species is responsible for the appearance of fluorescence.

15.
Chem Commun (Camb) ; 50(44): 5881-3, 2014 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-24756540

RESUMO

Asymmetric, heteroleptic dinuclear bis(dipyrrinato)zinc(II) complexes were synthesized and demonstrated to collect a wide range of light across the UV and visible regions (340-655 nm). The complexes also conveyed excitons across their structure from one end to the other, with spectroscopic studies demonstrating quantitative and fast energy transfer.


Assuntos
Compostos de Zinco/química , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Compostos de Zinco/síntese química
16.
Dalton Trans ; 41(46): 14035-7, 2012 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-23073502

RESUMO

We synthesised heteroleptic azadipyrrinato-dipyrrinato hybrid zinc(II) complex 1-Zn-2, by means of the stepwise coordination method. Homoleptic bis(azadipyrrinato)zinc(II) complex 1-Zn-1 was non-fluorescent, whereas 1-Zn-2 exhibited detectable fluorescence from azadipyrrinato ligand 1.

17.
J Phys Chem B ; 116(36): 11323-31, 2012 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-22897246

RESUMO

To demonstrate a new family of ionic liquids (ILs), i.e., "solvate" ionic liquids, the properties (thermal, transport, and electrochemical properties, Lewis basicity, and ionicity) of equimolar molten mixtures of glymes (triglyme (G3) and tetraglyme (G4)) and nine different lithium salts (LiX) were investigated. By exploring the anion-dependent properties and comparing them with the reported data on common aprotic ILs, two different classes of liquid regimes, i.e., ordinary concentrated solutions and "solvate" ILs, were found in the glyme-Li salt equimolar mixtures ([Li(glyme)]X) depending on the anionic structures. The class a given [Li(glyme)]X belonged to was governed by competitive interactions between the glymes and Li cations and between the counteranions (X) and Li cations. [Li(glyme)]X with weakly Lewis basic anions can form long-lived [Li(glyme)](+) complex cations. Thus, they behaved as typical ionic liquids. The lithium "solvate" ILs based on [Li(glyme)]X have many desirable properties for lithium-conducting electrolytes, including high ionicity, a high lithium transference number, high Li cation concentration, and high oxidative stability, in addition to the common properties of ionic liquids. The concept of "solvate" ionic liquids can be utilized in an unlimited number of combinations of other metal salts and ligands, and will thus open a new field of research on ionic liquids.

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