Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 63
Filtrar
Mais filtros

Bases de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Mol Pharm ; 20(4): 2276-2287, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36946991

RESUMO

To deal with the broad spectrum of coronaviruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), that threaten human health, it is essential to not only drugs develop that target viral proteins but also consider drugs that target host proteins/cellular processes to protect them from being hijacked for viral infection and replication. To this end, it has been reported that autophagy is deeply involved in coronavirus infection. In this study, we used airway organoids to screen a chemical library of autophagic modulators to identify compounds that could potentially be used to fight against infections by a broad range of coronaviruses. Among the 80 autophagy-related compounds tested, cycloheximide and thapsigargin reduced SARS-CoV-2 infection efficiency in a dose-dependent manner. Cycloheximide treatment reduced the infection efficiency of not only six SARS-CoV-2 variants but also human coronavirus (HCoV)-229E and HCoV-OC43. Cycloheximide treatment also reversed viral infection-induced innate immune responses. However, even low-dose (1 µM) cycloheximide treatment altered the expression profile of ribosomal RNAs; thus, side effects such as inhibition of protein synthesis in host cells must be considered. These results suggest that cycloheximide has broad-spectrum anti-coronavirus activity in vitro and warrants further investigation.


Assuntos
COVID-19 , Coronavirus Humano 229E , Humanos , SARS-CoV-2 , Cicloeximida/farmacologia , Autofagia
2.
Biochem Biophys Res Commun ; 558: 231-238, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-32113685

RESUMO

Several groups have developed in vitro expansion cultures for mouse metanephric nephron progenitor cells (NPCs) using cocktails of small molecules and growth factors including BMP7. However, the detailed mechanisms by which BMP7 acts in the NPC expansion remain to be elucidated. Here, by performing chemical screening for BMP substitutes, we identified a small molecule, TCS21311, that can replace BMP7 and revealed a novel inhibitory role of BMP7 in JAK3-STAT3 signaling in NPC expansion culture. Further, we found that TCS21311 facilitates the proliferation of mouse embryonic NPCs and human induced pluripotent stem cell-derived NPCs when added to the expansion culture. These results will contribute to understanding the mechanisms of action of BMP7 in NPC proliferation in vitro and in vivo and to the stable supply of NPCs for regenerative therapy, disease modeling and drug discovery for kidney diseases.


Assuntos
Proteína Morfogenética Óssea 7/metabolismo , Inibidores de Janus Quinases/farmacologia , Néfrons/citologia , Néfrons/efeitos dos fármacos , Animais , Proteína Morfogenética Óssea 7/administração & dosagem , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Meios de Cultura , Avaliação Pré-Clínica de Medicamentos , Humanos , Técnicas In Vitro , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Janus Quinase 3/antagonistas & inibidores , Camundongos , Camundongos da Linhagem 129 , Camundongos Transgênicos , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/efeitos dos fármacos , Células-Tronco Embrionárias Murinas/metabolismo , Néfrons/metabolismo , Transdução de Sinais/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas
3.
Chemistry ; 26(9): 1931-1935, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-31750583

RESUMO

In this paper, we describe an efficient and atom-economical synthesis of highly functionalized pyrroles, pentafulvenes, and pyrrolopyridines by [2+2] cycloaddition-retroelectrocyclization of N-substituted propargylamines with tetracyanoethylene, followed by the treatment of the resulting tetracyanobutadiene derivatives with silica gel. In this reaction, silica gel plays an important role to promote the intramolecular cyclization to afford the heterocyclic products from the tetracyanobutadiene intermediates. The products were obtained selectively depending on the substituent on the nitrogen atom of the starting propargylamines.

4.
Org Biomol Chem ; 18(12): 2274-2282, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32150201

RESUMO

The preparation of phthalimides cross-conjugated with an azulene ring was established by a one-pot Diels-Alder reaction of the corresponding 2-aminofuran derivatives with several maleimides, without the isolation of the intermediately formed [4 + 2] cycloadducts. The structure, optical and electrochemical properties of the novel phthalimide derivatives were clarified by single-crystal X-ray analysis, UV/Vis and fluorescence spectra, spectroelectrochemistry and voltammetry experiments, and theoretical calculations. These results indicated that the substituents on the azulene ring greatly affect the optical and electrochemical properties of the molecules.

5.
J Org Chem ; 84(3): 1257-1275, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30620591

RESUMO

The nucleophilic aromatic substitution (SNAr) reaction of diethyl 6-bromoazulene-1,3-dicarboxylate (1) with a variety of amines afforded the corresponding 6-aminoazulene derivatives 2a-2j in good-to-excellent yields. 6-Aminoazulene derivatives 3a-3f without the 1,3-diethoxycarbonyl functions were obtained by the deesterification of 2a-2f with 100% H3PO4. The reactivity of 6-aminoazulenes toward the bromination, SNAr, and palladium-catalyzed cross-coupling reactions was also clarified. 6-Arylazoazulenes 13a-13c were also prepared via the SNAr reaction of 1 with arylhydrazines, followed by oxidation with Pb(OAc)4 in the presence of N2H4. The structural, optical, and electrochemical properties of the 6-amino- and 6-arylazoazulenes were revealed by single-crystal X-ray structure analysis, UV/vis spectroscopy, voltammetry analysis, spectroelectrochemistry, and theoretical calculations.

6.
J Org Chem ; 83(12): 6690-6705, 2018 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-29799742

RESUMO

We describe the comparative study of optical and electrochemical properties of tetracyanobutadienes (TCBDs) and dicyanoquinodimethanes (DCNQs) with a 2-methyl-1-azulenyl group and their derivatives with a 1-azulenyl substituent examined under the same conditions. TCBDs and DCNQs with a 2-methyl-1-azulenyl substituent have been prepared by the Sonogashira-Hagihara alkynylation of the 2-methyl-1-iodoazulene with arylalkyne derivatives, followed by the formal [2+2] cycloaddition-retroelectrocyclization (CA-RE) reaction with tetracyanoethylene and 7,7,8,8-tetracyanoquinodimethane. The optical properties of the TCBDs and DCNQs with a 2-methyl-1-azulenyl group were investigated through the comparison with those of TCBDs and DCNQs with a 1-azulenyl substituent by employing the UV/vis spectroscopy and theoretical calculations. The electrochemical properties of the TCBD and DCNQ derivatives were also examined by cyclic voltammetry and differential pulse voltammetry experiments, which elucidated their multistep redox properties. Furthermore, noticeable spectral changes of these chromophores were identified by the spectroelectrochemical measurements.

7.
Org Biomol Chem ; 16(3): 480-489, 2018 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-29270584

RESUMO

The preparation of azulene-substituted benzofurans and isocoumarins was established by two types of intramolecular cyclization reaction of 1-ethynylazulenes. 2-(1-Azulenyl)- and 2,3-bis(1-azulenyl)benzofurans were prepared by the palladium-catalyzed cross-coupling reaction of 1-iodoazulenes with 2-ethynylphenol and that of 1-ethynylazulenes with 2-iodophenol under Sonogashira-Hagihara reaction conditions following the intramolecular nucleophilic addition of the oxygen nucleophile to the presumed 1-arylethynylazulenes. In contrast, 1-(phenylethynyl)azulenes bearing an o-methoxycarbonyl function on the substituted phenyl moiety exhibited intramolecular cyclization either in the presence of trifluoroacetic acid or N-iodosuccinimide (NIS) to afford azulene-substituted isocoumarins and 4-iodoisocoumarins, and the structures were clarified by single-crystal X-ray analysis. The optical properties of these compounds were also investigated by UV/vis spectroscopy and theoretical calculations.

8.
Mar Drugs ; 16(1)2018 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-29316695

RESUMO

Although pufferfish of the family Tetraodontidae contain high levels of tetrodotoxin (TTX) mainly in the liver, some species of pufferfish, boxfish of the family Ostraciidae, and porcupinefish of the family Diodontidae do not. To clarify the mechanisms, uptake of TTX and saxitoxins (STXs) into liver tissue slices of pufferfish, boxfish and porcupinefish was examined. Liver tissue slices of the pufferfish (toxic species Takifugu rubripes and non-toxic species Lagocephalus spadiceus, L. cheesemanii and Sphoeroides pachygaster) incubated with 50 µM TTX accumulated TTX (0.99-1.55 µg TTX/mg protein) after 8 h, regardless of the toxicity of the species. In contrast, in liver tissue slices of boxfish (Ostracion immaculatus) and porcupinefish (Diodon holocanthus, D. liturosus, D. hystrix and Chilomycterus reticulatus), TTX content did not increase with incubation time, and was about 0.1 µg TTX/mg protein. When liver tissue slices were incubated with 50 µM STXs for 8 h, the STXs content was <0.1 µg STXs/mg protein, irrespective of the fish species. These findings indicate that, like the toxic species of pufferfish T. rubripes, non-toxic species such as L. spadiceus, L. cheesemanii and S. pachygaster, potentially take up TTX into the liver, while non-toxic boxfish and porcupinefish do not take up either TTX or STXs.


Assuntos
Fígado/metabolismo , Saxitoxina/metabolismo , Tetraodontiformes/metabolismo , Tetrodotoxina/metabolismo , Animais , Transporte Biológico , Saxitoxina/isolamento & purificação , Tetrodotoxina/isolamento & purificação , Fatores de Tempo , Distribuição Tecidual
9.
Diabetologia ; 60(8): 1454-1466, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28534195

RESUMO

AIMS/HYPOTHESIS: Pancreatic beta-like cells generated from human induced pluripotent stem cells (hiPSCs) or human embryonic stem cells (hESCs) offer an appealing donor tissue source. However, differentiation protocols that mainly use growth factors are costly. Therefore, in this study, we aimed to establish efficient differentiation protocols to change hiPSCs/hESCs to insulin (INS)+ cells using novel small-molecule inducers. METHODS: We screened small molecules that increased the induction rate of INS+ cells from hESC-derived pancreatic and duodenal homeobox 1 (PDX1)+ pancreatic progenitor cells. The differentiation protocol to generate INS+ cells from hiPSCs/hESCs was optimised using hit compounds, and INS+ cells induced with the compounds were characterised for their in vitro and in vivo functions. The inducing activity of the hit compounds was also examined using mouse embryonic pancreatic tissues in an explant culture system. Finally, RNA sequencing analyses were performed on the INS+ cells to elucidate the mechanisms of action by which the hit compounds induced pancreatic endocrine differentiation. RESULTS: One hit compound, sodium cromoglicate (SCG), was identified out of approximately 1250 small molecules screened. When SCG was combined with a previously described protocol, the induction rate of INS+ cells increased from a mean ± SD of 5.9 ± 1.5% (n = 3) to 16.5 ± 2.1% (n = 3). SCG induced neurogenin 3-positive cells at a mean ± SD of 32.6 ± 4.6% (n = 3) compared with 14.2 ± 3.6% (n = 3) for control treatment without SCG, resulting in an increased generation of endocrine cells including insulin-producing cells. Similar induction by SCG was confirmed using mouse embryonic pancreatic explants. We also confirmed that the mechanisms of action by which SCG induced pancreatic endocrine differentiation included the inhibition of bone morphogenetic protein 4 signalling. CONCLUSIONS/INTERPRETATION: SCG improves the generation of pancreatic endocrine cells from multiple hiPSC/hESC lines and mouse embryonic pancreatic explants by facilitating the differentiation of endocrine precursors. This discovery will contribute to elucidating the mechanisms of pancreatic endocrine development and facilitate cost-effective generation of INS+ cells from hiPSCs/hESCs. DATA AVAILABILITY: The RNA sequencing data generated during the current study are available in the Gene Expression Omnibus ( www.ncbi.nlm.nih.gov/geo ) with series accession number GSE89973.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Animais , Proteína Morfogenética Óssea 4/metabolismo , Cromolina Sódica/farmacologia , Células-Tronco Embrionárias/efeitos dos fármacos , Células-Tronco Embrionárias/metabolismo , Proteínas de Homeodomínio/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Masculino , Camundongos , Pâncreas/citologia , Pâncreas/metabolismo , Transativadores/metabolismo
10.
Chemistry ; 23(21): 5126-5136, 2017 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-28191692

RESUMO

Synthesis of 2-aminofuran derivatives with an azulene or N,N-dimethylanilino substituent was established by the formal [2+2] cycloaddition-retroelectrocyclization of 3-(1-azulenyl or N,N-dimethylanilino)-2-propyn-1-ols with tetracyanoethylene, followed by intramolecular nucleophilic addition to the initially formed tetracyanobutadiene moiety of the internal hydroxyl group that come from 2-propyn-1-ol. The reaction proceeds under mild conditions with short reaction period. The products of the reaction are readily available through a simple purification procedure. 2-Aminofuran derivatives obtained by this reaction could be converted into 6-aminofulvene derivatives upon reaction with various amines. The structures of 2-aminofuran and 6-aminopentafulvene with a N,N-dimethylanilino substituent were confirmed by single-crystal X-ray structural analysis.

11.
Langmuir ; 33(3): 680-684, 2017 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-28045538

RESUMO

As-synthesized [Zn2(Oxac) (Taz)2]·(H2O)2.5, referred to as ZOTW2.5, was prepared from aqueous methanol solutions of Zn5(CO3)2(OH)6 and two kinds of ligands of 1,2,4-triazole (Taz) and oxalic acid (Oxac) at 453 K for 12 h. The crystal structure was determined by the Rietveld method. As-synthesized ZOTW2.5 was pretreated at 383 K and 1 mPa for tpt h, ZOTWx(tpth). ZOTWx(≥3h) showed a type I adsorption isotherm for N2 at 77 K having a saturation amount (Vs) of 180 mg/g, but that pretreated shortly showed only 1/10 in Vs. CO2 was adsorbed at 303 K in sigmoid on nonporous ZOTWx(≤2h) and in Langmuir-type on ZOTWx(≥3h) to reach the adsorption amount of 120 mg/g at 700 Torr. N2 adsorption on ZOTWx(≤2h)deCO2, degassed after CO2 adsorption on ZOTWx(≤2h), was promoted 5-fold from 180 mg/g on ZOTWx(tpth) and ZOTWx(≥3h)deCO2 up to ca. 1000 mg/g. The interaction of CO2 and H2O molecules in micropores may lead to a new route for micropore formation.

12.
J Org Chem ; 82(3): 1657-1665, 2017 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-28094947

RESUMO

Tetrathiafulvalene (TTF) derivatives with 2-azulenyl substituents 5-11 were prepared by the palladium-catalyzed direct arylation reaction of 2-chloroazulenes with TTF in good yield. Photophysical properties of these compounds were investigated by UV-vis spectroscopy and theoretical calculations. Redox behavior of the novel azulene-substituted TTFs was examined by using cyclic voltammetry and differential pulse voltammetry, which revealed their multistep electrochemical oxidation and/or reduction properties. Moreover, these TTF derivatives showed significant spectral change in the visible region under the redox conditions.

13.
Org Biomol Chem ; 15(18): 3917-3923, 2017 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-28426084

RESUMO

The SNAr reaction of 2-chloroazulene derivative 1 with ethoxycarbonyl groups at the 1,3-positions of the azulene ring with several amines afforded the corresponding 2-aminoazulenes 3-9 in excellent yields. 2-Chloroazulene (2) without the electron-withdrawing groups reacted with highly nucleophilic cyclic amines (i.e., morpholine, piperidine and pyrrolidine) under the high-temperature conditions in a sealed tube to produce the corresponding 2-aminoazulenes 10-12 in good yields. 2-Aminoazulenes 10-14 without the electron-withdrawing groups were also obtained in good yields by the treatment of compounds 3-7 with 100% H3PO4, but in the cases of the reaction of 8 and 9 with a secondary amine function, the decomposition of the products resulted. The synthesis of 2-arylazoazulenes 15-18 was also established via the SNAr reaction of 1 with arylhydrazines. The optical and electrochemical properties of the 2-arylazoazulene derivatives were examined by UV/Vis spectroscopy, theoretical calculations and voltammetric experiments.

14.
Mycorrhiza ; 26(8): 847-861, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27371100

RESUMO

Tricholoma matsutake is an ectomycorrhizal basidiomycete that produces prized, yet uncultivable, "matsutake" mushrooms along densely developed mycelia, called "shiro," in the rhizosphere of coniferous forests. Pinus densiflora is a major host of this fungus in Japan. Measuring T. matsutake biomass in soil allows us to determine the kinetics of fungal growth before and after fruiting, which is useful for analyzing the conditions of the shiro and its surrounding mycorrhizosphere, predicting fruiting timing, and managing forests to obtain better crop yields. Here, we document a novel method to quantify T. matsutake mycelia in soil by quantifying a single-copy DNA element that is uniquely conserved within T. matsutake but is absent from other fungal species, including close relatives and a wide range of ectomycorrhizal associates of P. densiflora. The targeted DNA region was amplified quantitatively in cultured mycelia that were mixed with other fungal species and soil, as well as in an in vitro co-culture system with P. densiflora seedlings. Using this method, we quantified T. matsutake mycelia not only from shiro in natural environments but also from the surrounding soil in which T. matsutake mycelia could not be observed by visual examination or distinguished by other means. It was demonstrated that the core of the shiro and its underlying area in the B horizon are predominantly composed of fungal mycelia. The fungal mass in the A or A0 horizon was much lower, although many white mycelia were observed at the A horizon. Additionally, the rhizospheric fungal biomass peaked during the fruiting season.


Assuntos
DNA Fúngico/genética , Reação em Cadeia da Polimerase/métodos , Tricholoma/fisiologia , Biomassa , Marcadores Genéticos , Genoma Fúngico , Cinética , Micélio , Sensibilidade e Especificidade , Serina Endopeptidases , Microbiologia do Solo , Especificidade da Espécie
15.
Kyobu Geka ; 68(7): 523-7, 2015 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-26197828

RESUMO

A 24-day-old boy suddenly developed progressive heart failure and was transported to our hospital. Echocardiography showed massive mitral regurgitation due to chordal rupture. Mitral valve repair was performed at 28 days of life, but postoperative valvular function was not satisfactory. A mechanical valve was implanted in the supra-annular position at 37 days of life. Two months after valve replacement, the mechanical valve was suddenly stuck. Emergent redo valve replacement was performed, but the prosthetic valve became stuck again 2 months after the 3rd operation, despite sufficient anti-coagulation therapy. At the 4th operation (6 months after birth), we implanted a pulmonary autograft in the mitral position instead of another mechanical valve in an emergent operation. The right ventricular outflow tract was reconstructed with a valved conduit. A postoperative catheter examination, which was performed 1 year after the Ross II operation, showed mild mitral stenosis with no regurgitation. Previous reports of Ross II operations in infants are rare and long-term results are unknown. However, we advocate that this procedure should be a rescue operation for mitral valve dysfunction in the early period of infants.


Assuntos
Insuficiência da Valva Mitral/cirurgia , Valva Mitral/cirurgia , Autoenxertos , Procedimentos Cirúrgicos Cardíacos , Doença Crônica , Humanos , Lactente , Recém-Nascido , Masculino , Reoperação , Tomografia Computadorizada por Raios X , Transplante Autólogo
16.
Am J Med Genet A ; 164A(8): 1899-908, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24715670

RESUMO

Mowat-Wilson syndrome (MWS) is a multiple congenital anomaly syndrome characterized by moderate or severe intellectual disability, a characteristic facial appearance, microcephaly, epilepsy, agenesis or hypoplasia of the corpus callosum, congenital heart defects, Hirschsprung disease, and urogenital/renal anomalies. It is caused by de novo heterozygous loss of function mutations including nonsense mutations, frameshift mutations, and deletions in ZEB2 at 2q22. ZEB2 encodes the zinc finger E-box binding homeobox 2 protein consisting of 1,214 amino acids. Herein, we report 13 nonsense and 27 frameshift mutations from 40 newly identified MWS patients in Japan. Although the clinical findings of all the Japanese MWS patients with nonsense and frameshift mutations were quite similar to the previous review reports of MWS caused by nonsense mutations, frameshift mutations and deletions of ZEB2, the frequencies of microcephaly, Hirschsprung disease, and urogenital/renal anomalies were small. Patients harbored mutations spanning the region between the amino acids 55 and 1,204 in wild-type ZEB2. There was no obvious genotype-phenotype correlation among the patients. A transfection study demonstrated that the cellular level of the longest form of the mutant ZEB2 protein harboring the p.D1204Rfs*29 mutation was remarkably low. The results showed that the 3'-end frameshift mutation of ZEB2 causes MWS due to ZEB2 instability.


Assuntos
Estudos de Associação Genética , Doença de Hirschsprung/genética , Proteínas de Homeodomínio/genética , Deficiência Intelectual/genética , Microcefalia/genética , Proteínas Repressoras/genética , Adolescente , Adulto , Alelos , Linhagem Celular , Criança , Pré-Escolar , Códon sem Sentido , Fácies , Feminino , Mutação da Fase de Leitura , Expressão Gênica , Doença de Hirschsprung/diagnóstico , Doença de Hirschsprung/epidemiologia , Proteínas de Homeodomínio/metabolismo , Humanos , Lactente , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/epidemiologia , Japão , Masculino , Microcefalia/diagnóstico , Microcefalia/epidemiologia , Fenótipo , Prevalência , Estabilidade Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Repressoras/metabolismo , Adulto Jovem , Homeobox 2 de Ligação a E-box com Dedos de Zinco
17.
Langmuir ; 30(48): 14680-5, 2014 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-25400032

RESUMO

Redox-active polymer gels consisting of polysiloxane backbone and bis(benzodithiolyl)bithienyl units have been designed and synthesized. The bis(benzodithiolyl)bithienyl units, which undergo interconversion between cyclic form and opened dicationic form, have been incorporated into polysiloxane backbone via hydrosilylation of vinyl-terminated bis(benzodithiolyl)bithienyl derivative and poly(methylhydrosiloxane) (PMHS) or poly(dimethylsiloxane-co-hydrogenmethylsiloxane) (PDMS-co-PMHS), resulting in polymer gels cross-linked with bis(benzodithiolyl)bithienyl units. After the incorporation of M1 into polysiloxane backbone, these polymer gels (P1 and P2) also exhibit redox responses associated with the electrochemical interconversion of the bis(benzodithiolyl)bithienyl moieties. The polymer gels show swelling behavior upon chemical oxidization, and bending behavior has been observed for the polymer gel immobilized poly(vinylidene difluoride) (PVdF) film. These results provide a useful perspective for fabricating redox-triggered polymer gel actuators based on the conformational change of the functional molecular unit.

18.
J Org Chem ; 79(14): 6590-602, 2014 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-24955756

RESUMO

Molecular switches composed of a benzodithiolylbithienyl scaffold and biphenyl or terphenyl mesogenic substituents were designed and synthesized. The molecular switches could undergo redox-triggered interconversion between the cationic form and cyclized neutral form, and this was confirmed using cyclic voltammetry and UV-vis spectroscopy. Binary complexes consisting of the molecular switches and a liquid crystalline polymer (LCP) were prepared to investigate the function of these redox-active molecular switches as actuating dopants. X-ray diffraction measurements were performed to determine the differences between the layer spacings of the complexes in the liquid crystalline phase with the oxidized and reduced states of the molecular switches. The LCP that was doped with the oxidized cationic form of the molecular switch had layer spacings that were up to 4% larger than the layer spacings in the polymer that was doped with the reduced cyclized molecular switch. Our approach will allow stimulus-responsive deformable materials to be constructed and give an impetus for fabricating redox-driven soft actuators.

19.
Mycologia ; 106(3): 397-406, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24871598

RESUMO

Tricholoma matsutake is the most commercially important edible mushroom in pine forests in Japan. Tricholoma bakamatsutake and T. fulvocastaneum, species closely related to T. matsutake, occur in Fagaceae forests. We examined ectomycorrhizal (EM) formation by these Tricholoma species by in vitro synthesis among seven strains (two of T. matsutake, four of T. bakamatsutake, one of T. fulvocastaneum) and axenic plants of pine (Pinus densiflora) and oak (Quercus serrata, Q. phillyraeoides). All strains, except for one of T. matsutake, formed EM associations with both pine and oak. Plant growth and mycelial development were differently affected by EM formation depending on the plant-fungus combination.


Assuntos
Fagaceae/microbiologia , Especificidade de Hospedeiro , Traqueófitas/microbiologia , Tricholoma/fisiologia , Biodiversidade , Micélio/classificação , Micélio/crescimento & desenvolvimento , Micélio/isolamento & purificação , Micélio/fisiologia , Tricholoma/classificação , Tricholoma/crescimento & desenvolvimento , Tricholoma/isolamento & purificação
20.
Kyobu Geka ; 66(7): 545-50, 2013 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-23917131

RESUMO

Pulmonary artery sling is frequently combined with tracheal stenosis, and occasionally combined with congenital heart defects. However, there are few reports of successfully treated cases that were combined with single ventricle. In this article, we report a successfully treated case of pulmonary artery sling combined with tracheal stenosis, single ventricle, pulmonary atresia, vascular ring, and bilateral superior vena cava. A male infant was referred to our hospital for central cyanosis, and was diagnosed with single ventricle (tricuspid stenosis, multiple ventricular septal defect, and hypoplastic right ventricle)with pulmonary atresia by echocardiogram. Tracheal stenosis was shown at cardiac catheterization. Pulmonary artery sling and tracheal diverticulum were diagnosed by computed tomography (CT) and magnetic resonance imaging(MRI)examination. Furthermore, the patient was complicated by vascular ring, which consisted of right aortic arch, an aberrant left subclavian artery, and patent ductus arteriosus, and this ductus arteriosus was connected to the left subclavian artery and pulmonary arterial trunk. After 6 months of medical treatment, including continuous infusion of prostaglandin, re-evaluation was performed by cardiac catheterization. We considered that bidirectional cavo-pulmonary shunt was appropriate for the patient since his pulmonary vasculature had matured well. An operation was performed under the use of cardio-pulmonary bypass. Release of vascular ring by division of the ductus, bilateral bidirectional cavo-pulmonary shunt, and a slide tracheoplasty for tracheal stenosis were performed simultaneously. His recovery was uneventful, and he is currently waiting to receive a Fontan-type operation.


Assuntos
Técnica de Fontan/métodos , Ventrículos do Coração/anormalidades , Artéria Pulmonar/anormalidades , Artéria Pulmonar/cirurgia , Reimplante/métodos , Traqueia/cirurgia , Permeabilidade do Canal Arterial/cirurgia , Derivação Cardíaca Direita , Humanos , Recém-Nascido , Masculino , Reoperação
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA