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1.
J Virol ; 97(5): e0034023, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-37166307

RESUMO

Measles virus (MeV), the causative agent of measles, is an enveloped RNA virus of the family Paramyxoviridae, which remains an important cause of childhood morbidity and mortality. MeV has two envelope glycoproteins, the hemagglutinin (H) and fusion (F) proteins. During viral entry or virus-mediated fusion between infected cells and neighboring susceptible cells, the head domain of the H protein initially binds to its receptors, signaling lymphocytic activation molecule family member 1 (SLAM) and nectin-4, and then the stalk region of the H protein transmits the fusion-triggering signal to the F protein. MeV may persist in the human brain and cause a fatal neurodegenerative disease, subacute sclerosing panencephalitis (SSPE). Recently, we showed, using in vitro cell culture, that cell adhesion molecule (CADM) 1 and CADM2 are host factors that trigger hyperfusogenic mutant F proteins, causing cell-to-cell fusion and the transfer of the MeV genome between neurons. Unlike conventional receptors, CADM1 and CADM2 interact in cis (on the same membrane) with the H protein and then trigger membrane fusion. Here, we show that alanine substitutions in part of the stalk region (positions 171-175) abolish the ability of the H protein to mediate membrane fusion triggered by CADM1 and CADM2, but not by SLAM. The recombinant hyperfusogenic MeV carrying this mutant H protein loses its ability to spread in primary mouse neurons as well as its neurovirulence in experimentally infected suckling hamsters. These results indicate that CADM1 and CADM2 are key molecules for MeV propagation in the brain and its neurovirulence in vivo. IMPORTANCE Measles is an acute febrile illness with skin rash. Despite the availability of highly effective vaccines, measles is still an important cause of childhood morbidity and mortality in many countries. The World Health Organization estimates that more than 120,000 people died from measles worldwide in 2021. Measles virus (MeV), the causative agent of measles, can also cause a fatal progressive neurological disorder, subacute sclerosing panencephalitis (SSPE), several years after acute infection. There is currently no effective treatment for this disease. In this study, using recombinant MeVs with altered receptor usage patterns, we show that cell adhesion molecule (CADM) 1 and CADM2 are host factors critical for MeV spread in neurons and its neurovirulence. These findings further our understanding of the molecular mechanism of MeV neuropathogenicity.


Assuntos
Sarampo , Doenças Neurodegenerativas , Panencefalite Esclerosante Subaguda , Cricetinae , Humanos , Camundongos , Animais , Vírus do Sarampo/fisiologia , Panencefalite Esclerosante Subaguda/genética , Hemaglutininas/metabolismo , Doenças Neurodegenerativas/metabolismo , Proteínas Virais de Fusão/genética , Proteínas Virais de Fusão/metabolismo , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Proteínas Recombinantes/metabolismo , Neurônios , Molécula 1 de Adesão Celular/metabolismo
2.
Sci Technol Adv Mater ; 24(1): 2183711, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36891540

RESUMO

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.

3.
Chemphyschem ; 22(15): 1638-1644, 2021 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-33971071

RESUMO

A series of acetyl pyrenes and pyrenyl ynones with and without tert-butyl groups showed distinct mechanofluorochromism (MFC). Four pairs of polymorphic solids were found out of six compounds and interestingly, each of them showed hypsochromic, bathochromic or off-to-on MFC. The MFC properties were rationalized by categorizing the packing schemes into herringbone, sandwich, beta and gamma motifs depending on the relative contributions of C⋅⋅⋅C (or π-π) against C⋅⋅⋅H contacts. The bulky tert-butyl and trimethylsilyl groups served not only to reduce the number of aggregation patterns but also to prohibit the complete back reactions in solid state. Our results suggest that the simple pyrene derivatives may be promising candidates for a novel group of mechanically-sensitive materials.

4.
Photochem Photobiol Sci ; 19(2): 229-234, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-31971525

RESUMO

Aiming to develop a library of organic mechanofluorochromic (MFC) materials, solid-state emission properties of pyrene-derivatives with amidophosphonate groups (diethyl 1-(pyrene-1-carboxamido)alkylphosphonates, alkyl: methyl, isopropyl, phenyl) were investigated. All of these compounds were found to show strong blue fluorescence, and blue-to-green emission shift was identified upon grinding. Monomer and several excimer emissive species were identified by steady-state and time-resolved fluorescence investigations. The characteristic green-to-blue thermal back reaction was observed even at room temperature without additives, which would be related to the flexibility of side groups for molecular rearrangement. We here demonstrated that the pyrene-derived compounds can be attractive platforms to host MFC properties.

5.
Inorg Chem ; 57(12): 7097-7103, 2018 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-29862805

RESUMO

Three types of red luminescent Eu(III) complexes with Schiff base and hfa ligands (hfa: hexafluoroacetylacetonate), mononuclear [Eu(hfa)2(OAc)(salen)2] (OAc: acetate anion, salen: N,N'-bis(salicylidene)ethylenediamine), brick-type [Eu2(hfa)4(OAc)2(salbn)2] (salbn: N,N'-bis(salicylidene)-1,4-butanediamine), and polynuclear [Eu(hfa)2(OAc)(salhen)] n (salhen: N,N'-bis(salicylidene)-1,6-hexanediamine) are reported for white light-emitting diode (LED) devices. Among these complexes, brick-type [Eu2(hfa)4(OAc)2(salbn)2] excited by blue light (460 nm) exhibits the photosensitized quantum yield (Φπ-π* = 47%) and remarkably high efficiency of sensitization (ηsens = 96%). The efficiency of sensitization is caused by the excited state based on ligand-ligand interaction between the Schiff base and hfa ligands in Eu(III) complexes. To fabricate LED devices, the red luminescent [Eu2(hfa)4(OAc)2(salbn)2] was mounted on an InGaN blue LED chip.

6.
Inorg Chem ; 57(23): 14653-14659, 2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30422642

RESUMO

Novel Eu(III) coordination polymers with furan-based bridging ligands [Eu(hfa)3(Cy)] n and [Eu(hfa)3(Tol)] n (hfa: hexafluoroacetylacetonato, Cy: 2,5-bis(dicyclohexylphosphoryl)furan), Tol: 2,5-bis(di- p-tolylphosphoryl)furan) are reported. The rigidity of assembly steric structures was controlled by intermolecular interactions through the side groups in bridging ligands. They exhibited one of the best performances (thermal stability above 320 °C and external photoluminescence quantum yields of up to 71%) among reported lanthanide(III) compounds. The triboluminescence activity was demonstrated to be dependent on the mechanical stability of the coordination polymers, which was proportional to the number of hydrogen atoms in the side groups. The second example of a large TL/PL spectral difference in [Tb,Eu(hfa)3(Tol)] n also revealed discrete photophysical processes under the conditions of grinding and UV irradiation.

7.
Angew Chem Int Ed Engl ; 56(25): 7171-7175, 2017 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-28508446

RESUMO

Luminescence upon the grinding of solid materials (triboluminescence, TL) has long been a puzzling phenomenon in natural science and has also attracted attention because of its broad application in optics. It has been generally considered that the TL spectra exhibit similar profiles as those of photoluminescence (PL), although they occur from distinct stimuli. Herein, we describe for the first time a large spectral difference between these two physical phenomena using lanthanideIII coordination polymers with efficient TL and PL properties. They are composed of emission centers (TbIII and EuIII ions), antenna (hexafluoroacetylacetonate=hfa), and bridging ligands (2,5-bis(diphenylphosphoryl)furan=dpf). The emission color upon grinding (yellow TL) is clearly different from that upon UV irradiation (reddish-orange PL) in TbIII /EuIII -mixed coordination polymers [Tb,Eu(hfa)3 (dpf)]n (Tb/Eu=1). The results directly indicate the discrete excitation processes of PL and TL.

8.
Angew Chem Int Ed Engl ; 55(39): 12059-62, 2016 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-27554795

RESUMO

Novel Eu(III) coordination polymers [Eu(hfa)3 (dpt)]n (dpt: 2,5-bis(diphenylphosphoryl)thiophene) and [Eu(hfa)3 (dpedot)]n (dpedot: 2,5-bis(diphenylphosphoryl)ethylenedioxythiophene) with hydrogen-bonded zipper structures are reported. The coordination polymers are composed of Eu(III) ions, hexafluoroacetylacetonato ligands, and thiophene-based phosphine oxide bridges. The zig-zag orientation of single polymer chains induced the formation of densely packed coordination structures with multiple intermolecular interactions, resulting in thermal stability above 300 °C. They exhibit a high intrinsic emission quantum yield (ca. 80 %) due to their asymmetrical and low-vibrational coordination structures around Eu(III) ions. Furthermore, the characteristic alternative orientation of substituents also contributes to the dramatically high ligand-to-metal energy transfer efficiencies of up to 80 % in the solid state.

9.
Inorg Chem ; 54(9): 4364-70, 2015 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-25872587

RESUMO

Syntheses of novel luminescent Eu(III) coordination glasses 1 ([Eu(hfa)3(o-dpeb)]2), 2 ([Eu(hfa)3(m-dpeb)]3), and 3 ([Eu(hfa)3(p-dpeb)]n) are reported. They are composed of Eu(III) ions, hexafluoroacetylacetonato (hfa) ligands, and unique bent-angled phosphine oxide (o-, m-, p-dpeb) ligands with ethynyl groups. Their coordination structures and glass formability are dependent on the regiochemistry of substitution in regard to the internal benzene core. Single-crystal X-ray analyses and DFT calculation reveals dinuclear, trinuclear, and polymer structures for Eu(III) coordination glasses 1, 2, and 3, respectively. Those compounds show characteristic glass-transition (Tg = 25-96 °C) and strong luminescence properties (ΦLn = 72-94%).

10.
J Phys Chem A ; 119(20): 4825-33, 2015 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-25875051

RESUMO

Enhanced luminescence of a lanthanide complex with dynamic polarization of the excited state and molecular motion is introduced. The luminescent lanthanide complex is composed of one Eu(hfa)3 (hfa, hexafluoroacetylacetonate) and two phosphine oxide ligands with ruthenocenyl units Rc, [Eu(hfa)3(RcPO)2] (RcPO = diphenylphosphorylruthenocene). The ruthenocenyl units in the phosphine oxide ligands play an important role of switching for dynamic molecular polarization and motion in liquid media. The oxidation states of the ruthenocenyl unit (Rc(1+)/Rc(1+)) are controlled by potentiostatic polarization. Eu(III) complexes attached with bidentate phosphine oxide ligands containing ruthenocenyl units, [Eu(hfa)3(RcBPO)] (RcBPO = 1,1'-bis(diphenylphosphoryl)ruthenocene), and with bidentate phosphine oxide ligands, [Eu(hfa)3(BIPHEPO)] (BIPHEPO =1,1'-biphenyl-2,2'-diylbis(diphenylphosphine oxide), were also prepared as references. The coordination structures and electrochemical properties were analyzed using single crystal X-ray analysis, cyclic voltammetry, and absorption spectroscopy measurements. The luminescence properties were estimated using an optoelectrochemical cell. Under potentiostatic polarization, a significant enhancement of luminescence was successfully observed for [Eu(hfa)3(RcPO)2], while no spectral change was observed for [Eu(hfa)3(RcBPO)]. In this study, the remarkable enhanced luminescence phenomena of Eu(III) complex based on the dynamic molecular motion under potentiostatic polarization have been performed.

11.
J Mater Chem C Mater ; 12(6): 1952-1957, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38343524

RESUMO

A family of (alkylsilyl)pyrene-1-carboxamides exhibits similar mechanofluorochromic responses upon grinding. However, their spontaneous fluorescence recovery processes are distinct despite their similarity in chemical structures and crystal packings. Fluorescence spectroscopy, crystallography, and nanomechanical tests revealed that the chromic direction is dominated by the packing motif, while the fluorescence recovery is driven by the intermolecular interactions and the reversibility of deformation.

12.
Sci Adv ; 9(4): eadf3731, 2023 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-36706187

RESUMO

Measles virus (MeV), which is usually non-neurotropic, sometimes persists in the brain and causes subacute sclerosing panencephalitis (SSPE) several years after acute infection, serving as a model for persistent viral infections. The persisting MeVs have hyperfusogenic mutant fusion (F) proteins that likely enable cell-cell fusion at synapses and "en bloc transmission" between neurons. We here show that during persistence, F protein fusogenicity is generally enhanced by cumulative mutations, yet mutations paradoxically reducing the fusogenicity may be selected alongside the wild-type (non-neurotropic) MeV genome. A mutant F protein having SSPE-derived substitutions exhibits lower fusogenicity than the hyperfusogenic F protein containing some of those substitutions, but by the wild-type F protein coexpression, the fusogenicity of the former F protein is enhanced, while that of the latter is nearly abolished. These findings advance the understanding of the long-term process of MeV neuropathogenicity and provide critical insight into the genotype-phenotype relationships of en bloc transmitted viruses.


Assuntos
Panencefalite Esclerosante Subaguda , Humanos , Panencefalite Esclerosante Subaguda/genética , Panencefalite Esclerosante Subaguda/metabolismo , Proteínas Virais de Fusão/genética , Proteínas Virais de Fusão/metabolismo , Vírus do Sarampo/genética , Encéfalo/metabolismo , Mutação
13.
Kansenshogaku Zasshi ; 81(6): 720-5, 2007 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-18095472

RESUMO

The frequency of diabetes mellitus has risen in Japan as the traditional diet has become increasing Americanized and society has aged. With this has come a rise in infectious diseases and complications elderly diabetic patients and a growing need for appropriate management to maintain their quality of life (QOL) and minimize medical measures. Subjects were 98 diabetic patients-60 men and 38 women hospitalized for intravenous antibiotic treatment of infectious disease from 2002 to 2005. We studied plasma glucose control, plasma and urinary protein levels related to nephropathy, and inflammatory responses to treatment. Subjects were divided into good (under 6.5%), fair (from 6.5% to 8.0%), poor (over 8.0%) and severe (over 10%) groups by HbA1c level on admission. We then compared white blood cell counts, CRP levels and the antibacterial medication periods. Those with poorly controlled plasma glucose control, hypoalbuminuria and interrupted or untreated diabetes required significantly longer antibacterial administration. Insulin was increased by the complications of infection, and decreased as infection ameliorated. Appropriate antibiotic administration is essential for diabetic patients with infectious disease, in addition to early intervention, strict plasma glucose control, continuous treatment, and maintenance of good nutrition. Such treatment improves QOL, shortens antibiotic administration, staves off antibiotic-resistant bacteria, and cuts medical costs.


Assuntos
Complicações do Diabetes/sangue , Infecções/sangue , Idoso , Antibacterianos/administração & dosagem , Glicemia/análise , Proteína C-Reativa/análise , Feminino , Humanos , Contagem de Leucócitos , Masculino
14.
Chem Sci ; 8(1): 423-429, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28451188

RESUMO

Thermometers whose emission color gradually changes with temperature are called chameleon emitters. In this study, we discuss the mechanism of the thermosensitivity of the emission color of polymers that contain two lanthanides (Ln3+), e.g., [Tb0.99Eu0.01(hfa)3(linker)] n , where the Ln3+(hfa)3 complexes (hfa: hexafluoro acetylacetonato) are connected by a phosphine oxide "linker" molecule. First, the difference in the thermosensitivities of the emissions from Tb3+ and Eu3+ are discussed. With increasing temperature, the green-emission intensity from Tb3+ decreases whereas the red-emission intensity from Eu3+ does not change. This was found to originate from the different reaction barriers for the quenching of the Ln3+ excited state via the intersystem crossing (ISC) between the hfa-centered triplet state and the ground state. Next, the excitation energy transfer (EET) from Tb3+ to Eu3+ is discussed. Although the direct EET between Ln3+ atoms is negligible because of the long distance between them, stepwise EET is found to occur via the linker-centered triplet state with a reasonable barrier. Thus, we propose a new idea-thermosensitivity can be controlled by the linker as well as by the ligand (hfa). To confirm the role of the linker, four phosphine oxides were examined. The thermosensitivity dependence on the linker is validated via experimental measurements.

15.
Intern Med ; 43(12): 1183-5, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15645655

RESUMO

A 81-year-old woman was diagnosed as having diabetes mellitus (DM) at 58 years of age. She started insulin therapy the following year, but her blood sugar levels were poorly controlled. At the age of 75, she tested positive for the anti-GAD antibody (7.8 U/ml) and was diagnosed as having slowly progressive type 1 DM (SPIDDM), as well as vitiligo vulgaris. At 78 years of age, chronic thyroiditis was diagnosed after positive tests for anti-thyroid peroxidase antibody and anti-thyroglobulin antibody. At the age of 81, general fatigue and jaundice appeared concomitantly with severe anemia, with Hb levels at 5.2 g/dl. Low serum vitamin B12 levels and the finding of erythroblastic hyperplasia with megaloblasts in bone marrow led to the diagnosis of pernicious anemia. Anemia was alleviated by intramuscular injections of vitamin B12. The patient developed chronic thyroiditis, vitiligo vulgaris, and pernicious anemia concomitantly with SPIDDM, and was diagnosed as having polyglandular autoimmune syndrome type III. Attention should be paid to these potentially associated autoimmune diseases in daily practice during the follow-up of SPIDDM patients.


Assuntos
Anemia Perniciosa/complicações , Diabetes Mellitus Tipo 1/complicações , Poliendocrinopatias Autoimunes/diagnóstico , Tireoidite/complicações , Vitiligo/complicações , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Progressão da Doença , Feminino , Humanos
16.
Intern Med ; 42(8): 714-8, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12924498

RESUMO

We report 7 cases of adrenal tumors with concurrent increases in cortisol and aldosterone secretion, which we have examined over the last 2 years. We also present the pathology of excised specimens based on immunohistochemical staining, as well as endocrinological findings. Four patients were male and 3 female; 6 were first diagnosed as suffering from primary aldosteronism (PA) and one as adrenal preclinical Cushing's syndrome (PCS). Plasma cortisol concentrations at midnight were greater than 2 microg/dl in 6 patients and more than 1 microg/dl in the dexamethasone suppression test with an 8 mg dose in all patients. This indicates that dexamethasone did not inhibit the secretion of cortisol. No increase in renin activity was seen in the renin-producing irritable test in any of the patients. Immunohistochemical staining showed not only the presence of aldosteronoma, but also the expression of P-450c17, which is involved in the biosynthesis of cortisol, indicating that both cortisol and aldosterone were concurrently synthesized. With regard to the function of adrenal tumors, we suggest that concurrent secretion of cortisol and aldosterone are not rare and that immunohistochemical examination of the surgically-extirpated specimen is important for diagnosis.


Assuntos
Neoplasias das Glândulas Suprarrenais/metabolismo , Aldosterona/biossíntese , Hidrocortisona/biossíntese , Neoplasias das Glândulas Suprarrenais/sangue , Adulto , Aldosterona/sangue , Técnicas de Diagnóstico Endócrino , Feminino , Humanos , Hidrocortisona/sangue , Masculino , Pessoa de Meia-Idade
19.
Biochem Biophys Res Commun ; 303(1): 306-12, 2003 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-12646203

RESUMO

Human bone marrow mesenchymal stem cells (hMSCs) give rise to adipocytes in response to adipogenic hormones. An in-house cDNA microarray representing 3400 genes was employed to characterize the modulation of genes involved in this process. A total of 197 genes showed temporal gene expression changes during adipogenesis, including genes encoding transcriptional regulators and signaling molecules. Semi-quantitative RT-PCR analyses confirmed differential expression at the transcriptional level of several genes identified by cDNA microarray screening. Cluster analysis of the genes regulated during the late phase (from day 7 to day 14) of hMSC adipogenesis indicated that these changes are well correlated with data previously reported for murine preadipocytes. However, during the early phase (day 1-day 5), the modulations of genes differed from those reported for the preadipocytes. These data provide novel information on the molecular mechanisms required for lineage commitment and maturation accompanying adipogenesis of hMSC.


Assuntos
Adipócitos/citologia , Adipócitos/metabolismo , Mesoderma/citologia , Células-Tronco/citologia , Diferenciação Celular , Linhagem Celular , DNA Complementar/metabolismo , Bases de Dados como Assunto , Regulação para Baixo , Corantes Fluorescentes/farmacologia , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Poli A/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Transcrição Gênica , Regulação para Cima
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