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1.
Chemistry ; 30(33): e202400615, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38591237

RESUMEN

In this work, bisarsine oxides were evaluated as novel bridging ligands, aiming to develop practical and efficient luminescent lanthanide coordination polymers. We have synthesized one-dimensional (1D) Eu3+ coordination polymers that incorporate bisarsine oxide bridging ligands and hexafluoroacetylacetonate anions. These polymers exhibited a denser packing of chains compared to analogous polymers bridged with bisphosphine oxides. The coordination polymers demonstrated exceptional thermal stability and substantial emission quantum yields. Additionally, the bisarsine oxides induced a pronounced polarization effect, facilitating a sensitive electric dipole transition that yields considerably narrow band red emission. Remarkably, the Eu3+ coordination polymers with bisarsine oxides maintained intense emission even at 550 K. A distinctive feature of these polymers is their heating-induced emission enhancement observed when the temperature was increased from 300 K to 400 K.

2.
Inorg Chem ; 63(22): 10108-10113, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38771149

RESUMEN

Metal-organic cages (MOCs) with luminophores have significant advantages for the facile detection of specific molecules based on turn-on or turn-off luminescence changes induced by host-guest complexation. One important challenge is the development of turn-on-type near-infrared (NIR)-luminescent MOCs. In this study, we synthesized a novel MOC consisting of two porphyrin dyes linked by four Yb(III) complexes, which exhibit bimodal red and NIR fluorescence signals upon photoexcitation of the porphyrin π system. Single-crystal X-ray structural analysis and computational molecular modeling revealed that planar aromatic perfluorocarbons were intercalated into the MOC. The tight packing between the MOC and guests enhanced the NIR fluorescence of Yb(III) by suppressing energy transfer from the photoexcited porphyrin to oxygen molecules. Guest-responsive turn-on NIR fluorescence changes in an MOC were successfully demonstrated.

3.
Inorg Chem ; 63(30): 13972-13979, 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-38996005

RESUMEN

Here, we report a photodynamic therapy (PDT) photosensitizer of N∧C∧N-coordinated Pt(II) complexes: [Pt(L)(solv)]+ (HL = 1,3-(2-dipyridyl)benzene) and [Pt(L)]+@HSA, which is the Pt(II) complex encapsulated in human serum albumin (HSA). The quantum yield of singlet oxygen production for [Pt(L)(solv)]+ is more than 50%, while that for [Pt(L)]+@HSA is much lower. Photoimages of human umbilical vein endothelial cells (HUVECs) treated with the Pt(II) complexes suggest that [Pt(L)(solv)]+ is delocalized in the entire cell after the fast uptake by diffusion and [Pt(L)]+@HSA is taken up by endocytosis and localized on organelles and the cell membrane. [Pt(L)(solv)]+ shows high photocytotoxicity for HUVECs, while [Pt(L)]+@HSA does not show photocytotoxicity.


Asunto(s)
Células Endoteliales de la Vena Umbilical Humana , Fotoquimioterapia , Fármacos Fotosensibilizantes , Humanos , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/síntesis química , Compuestos Organoplatinos/farmacología , Compuestos Organoplatinos/química , Compuestos Organoplatinos/síntesis química , Supervivencia Celular/efectos de los fármacos , Estructura Molecular , Oxígeno Singlete/metabolismo , Albúmina Sérica Humana/química , Albúmina Sérica Humana/metabolismo , Platino (Metal)/química , Platino (Metal)/farmacología , Tensoactivos/química , Tensoactivos/farmacología , Tensoactivos/síntesis química , Complejos de Coordinación/farmacología , Complejos de Coordinación/química , Complejos de Coordinación/síntesis química
4.
J Infect Chemother ; 30(7): 626-632, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38272262

RESUMEN

BACKGROUND: Information regarding the status of surgical antimicrobial prophylaxis (SAP) in Japanese hospitals is lacking. This study aimed to explore the status of SAP prescriptions for surgeries and adherence to Japanese SAP guidelines. METHODS: From February to July 2020, a 1-day multicentre point prevalent survey was conducted at 27 hospitals in Aichi Prefecture, Japan. Patients prescribed SAP were included in this study. The appropriateness of the SAP was evaluated based on the guidelines for selection of antimicrobials and their duration. Surgery was defined as appropriate when all the items were appropriate. RESULTS: A total of 728 patients (7.1 %; 728/10,199) received antimicrobials for SAP. Among them, 557 patients (76.5 %, 557/728) underwent the surgeries described in the guidelines. The overall appropriateness of all surgeries was 33.9 % (189/557). The appropriate selection of antimicrobial before/during and after surgery and their durations were 67.5 % (376/557), 67.5 % (376/557), and 43.3 % (241/557), respectively. The overall appropriateness ranged from 0 % (0/37, oral and maxillofacial surgery) to 58.7 % (88/150, orthopaedic surgery) and 27.7 % (36/130, community hospitals with 400-599 beds) to 47.2 % (17/36, specific hospitals). Cefazolin was the most prevalent antimicrobial prescribed before/during (55.5 %, 299/539), and after (45.1 %, 249/552) surgery. In total, 101 oral antimicrobials were prescribed postoperatively. CONCLUSIONS: SAP adherence by specific surgical fields and hospitals was shown in this study. Intensive intervention and repeated surveillance are necessary to improve SAP prescriptions in Japanese hospitals.


Asunto(s)
Profilaxis Antibiótica , Adhesión a Directriz , Hospitales , Infección de la Herida Quirúrgica , Humanos , Japón , Profilaxis Antibiótica/estadística & datos numéricos , Profilaxis Antibiótica/métodos , Profilaxis Antibiótica/normas , Infección de la Herida Quirúrgica/prevención & control , Adhesión a Directriz/estadística & datos numéricos , Hospitales/estadística & datos numéricos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Antibacterianos/uso terapéutico , Adulto , Guías de Práctica Clínica como Asunto , Anciano de 80 o más Años , Pueblos del Este de Asia
5.
Angew Chem Int Ed Engl ; : e202405584, 2024 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-38797714

RESUMEN

Large dissymmetry factor of the circularly polarized luminescence (gCPL) was observed in ligand and coordination tuned chiral tetrakis europium (Eu(III)) complexes with ammonium cations. The gCPL value was estimated to be -1.54, which is the largest among chiral luminescent molecules. Through photophysical measurements, single crystal X-ray structural analyses and quantum chemical calculations, changes in the geometric and electronic structures were observed for a series of chiral tetrakis Eu(III) complexes which enhanced the gCPL value. The emission quantum yield and photosensitized energy transfer efficiencies of chiral Eu(III) complexes with ammonium cations were also larger than those of chiral Eu(III) complex with Cs+. Based on the systematic modifications and analyses for chiral tetrakis Eu(III) complex, effect of the ammonium cation on enhanced CPL brightness is reported.

6.
Angew Chem Int Ed Engl ; 63(9): e202318548, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38169344

RESUMEN

Chiral D2 -symmetric figure-eight shaped macrocycles are promising scaffolds for amplifying the chiroptical properties of π-conjugated systems. By harnessing the inherent and adaptable conformational dynamics of a chiral C2 -symmetric bispyrrolidinoindoline (BPI) manifold, we developed an enantio-divergent modular synthetic platform to rapidly generate a diverse range of chiral macrocycles, spanning from 14- to 66-membered rings, eliminating the need for optical resolution. Notably, a 32-membered figure-eight macrocycle showed excellent circularly polarized luminescence (CPL: |glum |=1.1×10-2 ) complemented by a robust emission quantum yield (Φfl =0.74), to achieve outstanding CPL brightness (BCPL : ϵ×Φfl ×|glum |/2=480). Using quadruple Sonogashira couplings, this versatile synthetic platform enables precise adjustments of the angle, distance, and length among intersecting π-conjugated chromophores. Our synthetic strategy offers a streamlined and systematic approach to significantly enhance BCPL values for a variety of chiral D2 -symmetric figure-eight macrocycles.

7.
Inorg Chem ; 62(41): 16794-16800, 2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37733612

RESUMEN

Novel hydrophilic and color-changeable single chameleon luminophores composed of Tb(III)/Sm(III) nona-nuclear clusters [TbxSm9-x(Sal-PEG-n)16(µ-OH)10]+(NO3)- (x = 1, 2, 3, and 9; Sal-PEG-n: salicylate polyethylene glycolmethylester, n = 2 and 4) are reported for water mapping measurements. Their characteristic sandglass structures and aggregates were analyzed using X-ray single crystal analysis and dynamic light scattering (DLS) measurements. The green- and yellow-luminescence of [Tb3Sm6(Sal-PEG-4)16(µ-OH)]+(NO3)- in water were observed at 20 and 50 °C, respectively. The ratio-metric luminescence analysis using green Tb(III) and orange Sm(III) emission bands is a promising candidate for exact temperature distribution measurements in fluid dynamics. The effective temperature-sensing property based on the competitive intramolecular energy transfer processes between Tb(III)-to-ligand and Tb(III)-to-Sm(III) in a non-a-nuclear cluster is explained using temperature-dependent kinetic analyses in the excited state.

8.
Inorg Chem ; 62(29): 11325-11341, 2023 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-37432912

RESUMEN

We report on a facile method for the optical resolution of cyclometalated iridium(III) (Ir(III)) complexes via diastereomers formed with chiral auxiliaries. The racemic carboxylic acids of Ir(III) complexes (fac-4 (fac-Ir(ppyCO2H)3 (ppy: 2-phenylpyridine)), fac-6 (fac-Ir(tpyCO2H)3 (tpy: 2-(4'-tolyl)pyridine)), and fac-13 (fac-Ir(mpiqCO2H)3 (mpiq: 1-(4'-methylphenyl)isoquinoline))) were converted into the diastereomers, Δ- and Λ-forms of fac-9 (from fac-6), fac-10 (from fac-4), fac-11 (from fac-6), and fac-14 (from fac-13), respectively, by the condensation with (1R,2R)-1,2-diaminocyclohexane or (1R,2R)-2-aminocyclohexanol. The resulting diastereomers were separated by HPLC (with a nonchiral column) or silica gel column chromatography, and their absolute stereochemistry was determined by X-ray single-crystal structure analysis and CD (circular dichroism) spectra. Spectra of all diastereomers of the Ir(III) complexes are reported. Hydrolysis of the ester moieties of Δ- and Λ-forms of fac-10, fac-11, and fac-14 gave both enantiomers of the corresponding carboxylic acid derivatives in the optically pure forms, Δ-fac and Λ-fac-4, -6, and -13, respectively.

9.
Sci Technol Adv Mater ; 24(1): 2183711, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36891540

RESUMEN

Luminescent lanthanide coordination polymer crystals (LCPCs) represent an area of growing interest in materials chemistry owing to their unique and tailorable functional properties. The LCPCs provide a high level of structural tunability, including size- and morphology-dependent properties; therefore, they are promising materials for next-generation phosphors in a wide range of applications such as light emitting diodes. Here, by controlling the morphology of thermostable europium coordination polymer crystals, [Eu(hfa)3(dpbp)]n, hfa: hexafluoroacetylacetonate and dpbp:4,4'-bis(diphenyl phosphoryl) biphenyl), we realized a novel red phosphor with narrow linewidth emission (FWHM = 7.8 nm). The obtained luminescent LCPCs with unique structures were characterized by X-ray diffraction (XRD), scanning transmission electron microscopy (STEM), dynamic light scattering (DLS) and thermogravimetric analysis. Among, them, size tunable crystalline polymer spheres were found to have high internal quantum efficiency (ex., IQE = 79%) and highly thermostability (>300°C), and to exhibit dispersibility in PMMA media. The obtained results on the structural tunability of these materials can be used for the development of synthesis techniques for nanoscale materials based on crystalline lanthanide-based coordination phosphors.

10.
Chemistry ; 28(16): e202104401, 2022 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-35106844

RESUMEN

A spin-selective tribo-chemical reaction using a dinuclear lanthanide complex is demonstrated for the first time. The dinuclear complex is composed of two EuIII ions, hexafluoroacetylacetonato ligands, and anthracene-based phosphine oxide bridges. Single-crystal analysis revealed a face-to-face-type anthracene dimer structure in the dinuclear EuIII complex. Mechanical stimulus on the dinuclear EuIII complex induced selective formation of oxidized anthracene. The tribo-chemical reaction is based on a characteristic energy-transfer pathway for the selective formation of an excited triplet state.

11.
Chemistry ; 28(16): e202200593, 2022 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-35257421

RESUMEN

Invited for the cover of this issue are Yuichi Kitagawa, Yasuchika Hasegawa, and co-workers at Hokkaido University. The image depicts tribo-excited chemical reaction using trivalent lanthanide complexes with stacked anthracene ligands. Read the full text of the article at 10.1002/chem.202104401.

12.
Inorg Chem ; 61(44): 17662-17672, 2022 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-36300325

RESUMEN

In this study, we synthesized Eu3+ complexes containing arsine and phosphine oxides with annulated structures as the antenna ligands. The type of bridging in the annulated structures controlled the energy level of the triplet excited state and the intersystem crossing efficiency, leading to different emission properties. Eu3+ complexes bearing the arsine oxides showed a higher intensity ratio of electric/magnetic dipole transitions and energy-transfer efficiency than the complexes with the corresponding phosphine oxides.

13.
Appl Opt ; 61(2): 638-644, 2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-35200907

RESUMEN

The refraction of fluorescence from the inside of a sample at the surface results in fluctuations in fluorescence computed tomography (CT). We evaluated the influence of the difference in refractive index (RI) between the sample body and the surroundings on fluorescence CT results. The brightest fluorescent point is away from the correct point on the tomograms owing to the refraction. The speculated position is determined as the exact point if the RI ratio ranges between 0.97 and 1.03 by immersing the body in an RI matching liquid. The results can help in experimental settings of fluorescence CT for acquiring three-dimensional positional information.


Asunto(s)
Refractometría , Tomografía , Refracción Ocular , Tomografía Computarizada por Rayos X
14.
Chemistry ; 27(7): 2279-2283, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33094489

RESUMEN

A tribo-excited chemical reaction using a stacked lanthanide coordination polymer is demonstrated for the first time. The polymer is composed of a EuIII ion, hexafluoroacetylacetonato ligands, and an anthracene-based phosphine oxide bridge. The tightly stacked structure with hydrogen bonding was characterized by X-ray crystal structure analysis. The mechanical stimulus leads to tribo-excited oxidation in the EuIII coordination polymer. Electron ionization mass spectroscopy and photo-spectroscopic analysis reveal that the chemical product afforded by tribo-oxidation is different from that obtained by photo-oxidation.

15.
Chemistry ; 27(1): 264-269, 2021 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-32618063

RESUMEN

A design for an effective molecular luminescent thermometer based on long-range electronic coupling in lanthanide coordination polymers is proposed. The coordination polymers are composed of lanthanide ions EuIII and GdIII , three anionic ligands (hexafluoroacetylacetonate), and a chrysene-based phosphine oxide bridges (6,12-bis(diphenylphosphoryl)chrysene). The zig-zag orientation of the single polymer chains induces the formation of packed coordination structures containing multiple sites for CH-F intermolecular interactions, resulting in thermal stability above 350 °C. The electronic coupling is controlled by changing the concentration of the GdIII ion in the EuIII -GdIII polymer. The emission quantum yield and the maximum relative temperature sensitivity (Sm ) of emission lifetimes for the EuIII -GdIII polymer (Eu:Gd=1:1, Φtot =52 %, Sm =3.73 % K-1 ) were higher than those for the pure EuIII coordination polymer (Φtot =36 %, Sm =2.70 % K-1 ), respectively. Enhanced temperature sensing properties are caused by control of long-range electronic coupling based on phosphine oxide with chrysene framework.

16.
Chemistry ; 27(58): 14438-14443, 2021 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-34409670

RESUMEN

In this study, we have demonstrated a two-legged, upright molecular design method for monochromatic and bright red luminescent LnIII -silica nanomaterials. A novel EuIII -silica hybrid nanoparticle was developed by using a doubly binding TPPO-Si(OEt)3 (TPPO: triphenyl phosphine oxide) linker. The TPPO-Si(OEt)3 was confirmed by 1 H, 31 P, 29 Si NMR spectroscopy and single-crystal X-ray analysis. Luminescent Eu(hfa)3 and Eu(tfc)3 moieties (hfa: hexafluoroacetylacetonate, tfc: 3-(trifluoromethylhydroxymethylene)camphorate) were fixed onto TPPO-Si(OEt)3 -modified silica nanoparticles, producing Eu(hfa)3 (TPPO-Si)2 -SiO2 and Eu(tfc)3 (TPPO-Si)2 -SiO2 , respectively. Eu(hfa)3 (TPPO-Si)2 -SiO2 exhibited the higher intrinsic luminescence quantum yield (93 %) and longer emission lifetime (0.98 ms), which is much larger than those of previously reported EuIII -based hybrid materials. Eu(tfc)3 (TPPO-Si)2 -SiO2 showed an extra-large intrinsic emission quantum yield (54 %), although the emission quantum yield for the precursor Eu(tfc)3 (TPPO-Si(OEt)3 )2 was found to be 39 %. These results confirmed that the TPPO-Si(OEt)3 linker is a promising candidate for development of EuIII -based luminescent materials.


Asunto(s)
Luminiscencia , Nanopartículas , Europio , Dióxido de Silicio
17.
Inorg Chem ; 60(12): 8605-8612, 2021 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-34087071

RESUMEN

In this study, we focused on arsenic as a new potential motif for the ligand design of high-efficiency, luminous lanthanide complexes. A Eu3+ complex bearing triphenylarsine oxide had a photosensitized energy-transfer efficiency 7.9 times higher than that of a Eu3+ complex bearing triphenylphosphine oxide. This is mainly due to the heavy-atom effect of arsenic, which was supported by evaluating the photoluminescence spectra of their corresponding Gd3+ complexes.

18.
J Phys Chem A ; 125(1): 209-217, 2021 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-33400867

RESUMEN

Photophysical properties of europium (Eu(III)) complexes are affected by ligand-to-metal charge transfer (LMCT) states. Two luminescent Eu(III) complexes with three tetramethylheptadionates (tmh) and pyridine (py), [Eu(tmh)3(py)1] (seven-coordinated monocapped-octahedral structure) and [Eu(tmh)3(py)2] (eight-coordinated square antiprismatic structure), were synthesized for geometrical-induced LMCT level control. Distances between Eu(III) and oxygen atoms of tmh ligands were estimated using single-crystal X-ray analyses. The contribution percentages of π-4f mixing in HOMO and LUMO at the optimized structure in the ground state were calculated using DFT (LC-BLYP). The Eu-O distances and their π-4f mixed orbitals affect the energy level of LMCT states in Eu(III) complexes. The LMCT energy level of an eight-coordinated Eu(III) complex was higher than that of a seven-coordinated Eu(III) complex. The energy transfer processes between LMCT and Eu(III) ion were investigated using temperature-dependent and time-resolved emission lifetime measurements of 5D0 → 7FJ transitions of Eu(III) ions. In this study, the LMCT-dependent energy transfer processes of seven- and eight-coordinated Eu(III) complexes are demonstrated for the first time.

19.
Surg Today ; 51(1): 1-31, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33320283

RESUMEN

BACKGROUND: The guidelines for the prevention, detection, and management of gastroenterological surgical site infections (SSIs) were published in Japanese by the Japan Society for Surgical Infection in 2018. This is a summary of these guidelines for medical professionals worldwide. METHODS: We conducted a systematic review and comprehensive evaluation of the evidence for diagnosis and treatment of gastroenterological SSIs, based on the concepts of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. The strength of recommendations was graded and voted using the Delphi method and the nominal group technique. Modifications were made to the guidelines in response to feedback from the general public and relevant medical societies. RESULTS: There were 44 questions prepared in seven subject areas, for which 51 recommendations were made. The seven subject areas were: definition and etiology, diagnosis, preoperative management, prophylactic antibiotics, intraoperative management, perioperative management, and wound management. According to the GRADE system, we evaluated the body of evidence for each clinical question. Based on the results of the meta-analysis, recommendations were graded using the Delphi method to generate useful information. The final version of the recommendations was published in 2018, in Japanese. CONCLUSIONS: The Japanese Guidelines for the prevention, detection, and management of gastroenterological SSI were published in 2018 to provide useful information for clinicians and improve the clinical outcome of patients.


Asunto(s)
Procedimientos Quirúrgicos del Sistema Digestivo/efectos adversos , Guías de Práctica Clínica como Asunto , Sociedades Médicas/organización & administración , Infección de la Herida Quirúrgica/prevención & control , Infección de la Herida Quirúrgica/terapia , Profilaxis Antibiótica , Humanos , Japón , Atención Perioperativa , Infección de la Herida Quirúrgica/diagnóstico , Infección de la Herida Quirúrgica/etiología
20.
Surg Today ; 51(1): 32-43, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32277281

RESUMEN

Tumor necrosis factor-alpha inhibitor (TNFi) treatment is effective for ulcerative colitis (UC) and Crohn's disease (CD). Although several meta-analyses have been performed to evaluate the association between TNFi treatment and surgical morbidity, the results are controversial. We conducted a systematic review and meta-analysis of the prevention of surgical site infection (SSI) after surgery for UC and CD in patients on TNFis, based on literature published between January 2000 and May 2019 (registered on PROSPERO, No. CRD42019134156). Overall, 2175 UC patients in 13 observational studies (OBSs) and 7084 CD patients in 16 OBSs were included. The incidences of incisional (INC) SSI and organ/space (O/S) SSI after surgery for UC were 179/1985 (9.0%) and 176/2175 (8.1%), respectively. TNFi use was not associated with the incidences of INC SSI (odds ratio (OR) 1.04, 95% confidence interval (CI) (0.47-2.32) or O/S SSI (OR 1.85, 95% CI (0.82-4.20)) after surgery for UC. The INC SSI and O/S SSI incidences after surgery for CD were 289/3089 (9.4%) and 526/7,084 (7.4%), respectively. Preoperative TNFi use was not associated with INC SSI (OR 0.98, 95% CI (0.52-1.83)) or O/S SSI incidence (OR 1.09, 95% CI (0.78-1.52)) after surgery for CD. We did not find a significant association between preoperative TNFi use and SSI in surgery for UC or CD.


Asunto(s)
Colitis Ulcerosa/cirugía , Enfermedad de Crohn/cirugía , Procedimientos Quirúrgicos del Sistema Digestivo/efectos adversos , Infección de la Herida Quirúrgica/epidemiología , Infección de la Herida Quirúrgica/etiología , Factor de Necrosis Tumoral alfa/uso terapéutico , Colitis Ulcerosa/tratamiento farmacológico , Enfermedad de Crohn/tratamiento farmacológico , Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Humanos , Incidencia , Cuidados Preoperatorios , Factor de Necrosis Tumoral alfa/administración & dosificación
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