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1.
J Oleo Sci ; 71(5): 747-757, 2022 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-35387916

RESUMEN

Living cells and organelles are separated by a lipid membrane bilayer. It is possible to induce morphological changes in this membrane by disturbing the order of the membrane using external stimuli and understanding the details of this mechanism is expected to be applicable to intracellular transport. DBA (DBAB-BODIPY-aminopropyl), which contains (1) a DBAB (4-[di(biphenyl-4-yl)amino]azobenzene) moiety that undergoes photo-isomerization under visible light irradiation, and (2) a BODIPY (borondipyrromethene) fluorophore was synthesized. The π-π* transition absorptions of both the azo moiety and that of BODIPY moiety in DBA were observed, independently. The photo-isomerization rate constant of the DMSO solution of DBA at 299K is 5.5 ×10-3/s. The structure of the fluorescent group in DBA did not readily influence the isomerization. Upon introducing DBA into the lipid bilayer membranes of a vesicle suspension and irradiating the vesicles with visible light to isomerize the azo group, a morphological change in of the vesicles was observed due to the disturbance of the membrane order. Thus, DBA is a useful molecule for artificial modulation of the lipid membrane morphology.


Asunto(s)
Compuestos Azo , Membrana Dobles de Lípidos , Compuestos Azo/química , Luz , Membrana Dobles de Lípidos/química
2.
Trauma Case Rep ; 32: 100426, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33665319

RESUMEN

In inferior shoulder dislocation (ISD) cases, closed reduction usually achieves reduction and irreducible ISD is extremely rare. To date, only two cases requiring open reduction have been reported. Herein, we describe a case of an irreducible ISD that required open reduction. A 90-year-old woman fell at home and presented to our hospital. Plain radiography revealed a right ISD and greater tuberosity avulsion fracture. Because reduction under general anesthesia was difficult, we performed open reduction. The humeral head was entrapped by the inferior shoulder capsule. Since inferior instability remained after reduction, we reduced and fixed the greater tuberosity fracture and repaired the rotator cuff tear (RCT). This case suggested that humeral head entrapment by the inferior capsule and decreased force couple toward the humeral head by the greater tuberosity fracture and RCT cause irreducibility. Moreover, since instability can remain after reduction for ISD accompanying greater tuberosity fracture or RCT, preparing for implantations to repair these lesions is recommended.

3.
Int J STD AIDS ; 32(5): 483-485, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33570479

RESUMEN

Mycobacterium genavense, a nontuberculous Mycobacterium, is found in immunosuppressed patients, particularly in those with HIV. Mycobacterium genavense incubation under standard culture conditions is difficult, and its identification is challenging using routine culture methods. Herein, we report the case of a 40-year-old Japanese man with HIV presenting with disseminated M. genavense infection. An analysis using an automated blood culture system did not show positive signals during 6 weeks of incubation. However, an acid-fast bacilli smear of his blood sample was positive for the bacterium. Mycobacterium genavense was identified using sequencing analysis, targeting the heat shock protein 65 gene. The patient recovered from the infection, following antibiotic therapy for 18 months. Under suspicion of disseminated M. genavense infection and the absence of bacterial growth in blood culture samples, an acid-fast bacilli smear test of the sample may be useful for timely diagnosis.


Asunto(s)
Infecciones por Mycobacterium no Tuberculosas , Mycobacterium , Adulto , Cultivo de Sangre , Humanos , Huésped Inmunocomprometido , Masculino , Mycobacterium/genética , Infecciones por Mycobacterium no Tuberculosas/diagnóstico , Infecciones por Mycobacterium no Tuberculosas/tratamiento farmacológico
4.
Org Lett ; 22(15): 6192-6196, 2020 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-32666801

RESUMEN

A series of acene- or heteroacene-fused thiopyrylium salts was synthesized from diarylthioethers that contain formyl groups via an intramolecular Friedel-Crafts cyclization. The reaction, promoted by a Lewis or Brønsted acid, afforded the new thiopyrylium salts in good yield. Kinetic investigations and density functional theory calculations were used to explore the mechanism of the reaction. The electronic structures of the thiopyrylium salts were examined by UV-vis absorption spectroscopy, which afforded insight into the electronic transitions within these molecules.

5.
Org Biomol Chem ; 18(24): 4583-4589, 2020 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-32496495

RESUMEN

The reaction of acetophenone hydrazones with TeCl4 in the presence of DBU gave a mixture of divinyl ditellurides and divinyl tellurides, which easily reacted with Cu powder in refluxing toluene to afford divinyl tellurides in good yields. The reaction of divinyl tellurides with bromine (1.2 eq.) gave the corresponding tellurium dibromide rather than the addition of the double bond whereas 3 molar amount of bromine gave excess brominated and oxidized products. The reaction of divinyl tellurides with 2-(trimethylsilyl)phenyl triflate in the presence of CsF gave (E)-2-alkenyldiaryl tellurides in good yields.

6.
J Org Chem ; 85(12): 7748-7756, 2020 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-32449358

RESUMEN

A new family of thiophene-fused thiopyrylium salts has been synthesized via Lewis-acid-induced Rieche formylation, followed by an intramolecular Friedel-Crafts cyclization of a series of diarylthioethers. Moreover, in the case of diarylthioethers that bear formyl groups, Lewis-acid-promoted intramolecular cyclizations afforded novel thiophene-fused bisthiopyrylium salts in good yield. The electronic structures of the new compounds were determined experimentally by NMR and UV-vis absorption spectroscopy and theoretically investigated by density functional theory calculations. The results of our examinations revealed effective conjugation of the π-electrons over the entire linearly fused heteroacene framework.

7.
J Orthop Surg (Hong Kong) ; 28(1): 2309499019893079, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31876228

RESUMEN

The association between carpal tunnel syndrome (CTS) and remitting seronegative symmetrical synovitis with pitting edema (RS3PE) syndrome, an elderly onset rheumatic disease, is not fully understood. Here, we describe a case of acute CTS caused by RS3PE syndrome. An 84-year-old man visited the hospital with sudden onset of severe neuralgia in the median nerve and pitting edema in both hands. Computed tomography showed low-density areas around the flexor tendons and median nerve compression in the carpal tunnel. Rapidly progressing intolerable neuralgia and paralysis required urgent carpal tunnel release in the left hand. After surgery, we considered the possibility of RS3PE syndrome and started the administration of prednisolone. The pitting edema and neuralgia improved. In this case, imaging and intraoperative findings suggest that the effusion generated from flexor tenosynovitis associated with RS3PE syndrome increased the internal pressure in the carpal tunnel rapidly, which led to acute CTS and urgent surgery.


Asunto(s)
Síndrome del Túnel Carpiano/diagnóstico , Edema/complicaciones , Sinovitis/complicaciones , Tendones/diagnóstico por imagen , Anciano de 80 o más Años , Síndrome del Túnel Carpiano/etiología , Edema/diagnóstico , Humanos , Masculino , Sinovitis/diagnóstico , Tomografía Computarizada por Rayos X
8.
J Org Chem ; 83(12): 6373-6381, 2018 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-29792430

RESUMEN

The Buchwald-Hartwig amination of a phosphinine bearing a bromophenyl moiety was carried out using a dinuclear Ni catalyst. A variety of monoarylamines, diarylamines, and alkylamine, as well as heterocycles, were successfully converted into novel phosphinines bearing amine units. The photophysical properties of these novel phosphinines were examined, including the substituent-dependent absorption/emission features and intramolecular charge-transfer interactions.

9.
J Org Chem ; 83(4): 1969-1975, 2018 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-29392944

RESUMEN

The transformation of 1,2-bis(1-arylvinyl)ditellurides into 2,5-diaryltellurophenes by sequential ditelluride exchange and thermal intramolecular cyclization reactions is presented, and the optoelectronic properties of a series of 2,5-diaryltellurophenes with both electron-donating and electron-withdrawing aryl substituents are disclosed. Furthermore, the multicolored emissive tellurophenes in solution at room temperature have been demonstrated.

10.
FEBS Lett ; 592(4): 559-567, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29355929

RESUMEN

We have developed two types of fluorescent probes, DALGreen and DAPGreen, for monitoring autophagy, that exhibit fluorescence upon being incorporated into autophagosomes. DALGreen enhances its fluorescence at acidic pH, which is favorable for monitoring late-phase autophagy, whereas DAPGreen remains fluorescent with almost constant brightness during the autophagic process. With these probes that stain autophagosomes as they are being formed, the real-time change of autophagic phenomena of live cells may be traced, which is an advantage over conventional approaches with small molecules that stain mature autophagosomes. The use of both dyes allows monitoring of the membrane dynamics of autophagy in any type of cell without the need for genetic engineering, and therefore, will be useful as a tool to study autophagic phenomena.


Asunto(s)
Autofagia , Colorantes Fluorescentes/metabolismo , Animales , Autofagosomas/metabolismo , Supervivencia Celular , Células HeLa , Humanos , Ratones , Imagen Molecular
11.
ACS Chem Biol ; 12(10): 2546-2551, 2017 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-28925688

RESUMEN

There has been a growing interest in mitophagy, mitochondria-selective autophagy, which plays an essential role in maintaining intracellular homeostasis. We have developed a small-molecule fluorescent probe, Mtphagy Dye, for visualizing mitophagy, which was readily synthesized from a known perylene derivative, perylene-3,4-dicarboxylic anhydride. Mtphagy Dye has suitable fluorescent properties for detecting mitochondrial acidification during mitophagy in the long-wavelength region that does not damage mitochondria. Using Mtphagy Dye, we were able to visualize mitophagy with both cases of Parkin-dependent and -independent HeLa cells.


Asunto(s)
Autofagia/fisiología , Colorantes Fluorescentes/química , Mitocondrias/fisiología , Mitofagia/fisiología , Imagen Óptica/métodos , Perileno/análogos & derivados , Células HeLa , Humanos , Concentración de Iones de Hidrógeno , Cinética , Estructura Molecular , Perileno/química , Ubiquitina-Proteína Ligasas/metabolismo
12.
Org Lett ; 19(8): 2110-2113, 2017 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-28397494

RESUMEN

The synthesis of 1H-benzo[c]thio- and 1H-benzo[c]selenophen-2-ium tetrafluoroborates by the reaction of triphenylcarbenium tetrafluoroborate with 1-ethylidene-1,3-dihydrobenzo[c]thiophene or 1-ethylidene-1,3-dihydrobenzo[c]selenophene, respectively, is reported. The electronic structure of these novel 1H-benzo[c]chalcogenophenium salts was examined on the basis of their electronic spectra, whereby transitions were assigned in agreement with theoretical calculations. Electrochemical measurements revealed irreversible one-electron reduction waves for these 1H-benzo[c]chalcogenophenium salts.

13.
Nat Prod Commun ; 11(7): 895-898, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30452156

RESUMEN

Reaction of camphor hydrazone with TeCI4 under basic conditions gave an isomeric mixture of vinyl ditelluride and Wagner-Meerwein rearranged ditelluride. Initially formed tellurocamphor enolized and oxidized to give vinyl telluride, whereas tellurocamphor complexed with TeC4 to afford carbocation, which rearranged in a Wagner-Meerwein manner to afford the rearranged ditelluride. Photolysis of ditelluride in methyl methacrylate solution gave the radical polymerization product, PMMA, in which ditelluride acted as a radical initiator.


Asunto(s)
Alcanfor/análogos & derivados , Alcanfor/química , Hidrazonas/síntesis química , Hidrazonas/química , Estructura Molecular , Telurio
14.
Chem Commun (Camb) ; 50(98): 15525-8, 2014 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-25354542

RESUMEN

Dibenzo[b,h][1,6]naphthyridines were synthesized in one pot by reacting 2-acetylaminobenzaldehyde with methyl ketones under basic conditions via four sequential condensation reactions. This method was also applied to the synthesis of 1,2-dihydroquinolines. 6-Methyl-1,6-dibenzonaphthyridinium triflates showed strong fluorescence, and the fluorescence intensities were changed upon intercalation into double-stranded DNA.


Asunto(s)
ADN/química , Colorantes Fluorescentes/síntesis química , Sustancias Intercalantes/síntesis química , Naftiridinas/síntesis química , Benzaldehídos/química , Fluorescencia , Colorantes Fluorescentes/química , Sustancias Intercalantes/química , Cetonas/química , Naftiridinas/química , Quinolinas/síntesis química , Quinolinas/química
15.
Chem Commun (Camb) ; 48(90): 11145-7, 2012 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-23045242

RESUMEN

An efficient route to 4-aryl-2-naphthols from arynes and aroylacetones was developed by carbon-carbon bond insertion followed by an intramolecular aldol reaction and dehydration. Benzyne derived from 2-(trimethylsilyl)phenyl triflate reacted with benzoylacetones in refluxing acetonitrile to give 4-aryl-2-naphthols and 3-aryl-1-naphthols.

16.
Chem Commun (Camb) ; 47(20): 5822-4, 2011 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-21487614

RESUMEN

An efficient route to a variety of 2-phenylindolin-3-ones from amino acid methyl esters has been developed. The reaction of amino acid methyl esters with benzyne prepared from 2-(trimethylsilyl)phenyl triflate and CsF gave 2-phenylindolin-3-ones in moderate to good yields.


Asunto(s)
Aminoácidos/química , Cristalografía por Rayos X , Ésteres , Indoles/química , Conformación Molecular
17.
Bioorg Med Chem Lett ; 20(13): 3911-5, 2010 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-20605449

RESUMEN

In this study, a new type of fluorescence probe, diphenylpyrenylphosphine-conjugated alkyltriphenylphosphonium iodide which was accumulated in mitochondria, has been synthesized. This probe was detected peroxide in living cell. Comparison of the reactivity toward several peroxide indicated that the probe was existed in mitochondrial membrane. Using this probe, generation of peroxide in mitochondria of living cell was successfully visualized.


Asunto(s)
Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Mitocondrias/química , Compuestos Organofosforados/química , Compuestos Organofosforados/síntesis química , Peróxidos/análisis , Línea Celular Tumoral , Humanos , Microscopía Fluorescente , Estructura Molecular , Estereoisomerismo
18.
Org Lett ; 11(1): 169-71, 2009 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-19053733

RESUMEN

The reaction of salicylaldehydes with benzyne prepared from o-trimethylsilyphenyl triflate and CsF gave xanthenes and xanthones. When the reaction was carried out under basic conditions, 9-hydroxyxanthenes (xanthols) were obtained in good yields.


Asunto(s)
Aldehídos/química , Derivados del Benceno/química , Xantenos/síntesis química , Xantonas/síntesis química , Estructura Molecular , Estereoisomerismo , Xantenos/química , Xantonas/química
19.
Chemistry ; 12(29): 7742-8, 2006 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-16819724

RESUMEN

Treatment of di-tert-butylthioketene S-oxide (5 a) with Lawesson reagent at room temperature resulted in the formation of 3,3-di-tert-butylthiirane-2-thione (4 a) in high yield. The oxidation of 4 a with mCPBA (mCPBA=m-chloroperbenzioc acid) gave 3,3-di-tert-butylthiirane-2-thione S-oxide (6) almost quantitatively. The reactions of 4 a with dimethyl acetylenedicarboxylate (DMAD) and benzyne afforded dimethyl 2-(2,2,4,4-tetramethylpentan-3-ylidene)-1,3-dithiole-4,5-dicarboxylate (13) and 2-(2,2,4,4-tetramethylpentan-3-ylidene)benzo[d][1,3]dithiole (15), respectively, in high yields, suggesting that 4 a is an excellent 1,3-dipole. The reaction of 4 a with ethylenebis(triphenylphosphine)platinum (16) gave dithiolato-platinum complex (22) in high yield. The structure of 22 was determined by X-ray crystallographic analysis.

20.
Org Biomol Chem ; 4(14): 2745-52, 2006 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-16826299

RESUMEN

The reaction of adamantane-2-thione with propiolic acid afforded a novel type of cycloadduct, spiro[adamantane-2,2'-6'H-[1,3]-oxathiin]-6'-one (3a), in quantitative yield. The reaction of thiobenzophenone with propiolic acid gave 2,2-diphenyl-6'H-[1,3]-oxathiin]-6'-one and 4-phenyl-3-thia-3,4-dihydronaphthoic acid in 34% and 35% yields, respectively. The reaction might proceed through a concerted process, as confirmed by kinetics. The reaction of adamantane-2-thione with 2-butynoic acid or phenylpropiolic acid gave the corresponding adducts regioselectively. Interestingly, only one isomer was obtained by the reaction of thiofenchone with propiolic acid, suggesting that the reaction proceeded diastereospecifically. Oxidation of adducts by dimethyldioxirane or m-chloroperoxybenzoic acid gave the corresponding sulfoxides and sulfones. The sulfoxides were thermally decomposed to give disulfide or another type of 1,3-oxathiin-6-one.


Asunto(s)
Alquinos/química , Cetonas/química , Propionatos/química , Tionas/química , Adamantano/análogos & derivados , Adamantano/química , Estructura Molecular
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