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1.
Chem Sci ; 15(20): 7603-7609, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38784757

RESUMEN

Norcorrole derivatives with 3,4,5-trialkoxyphenyl moieties at the meso positions were synthesized to form various stacking assemblies in single crystals and thermotropic liquid crystals (LCs) depending on aliphatic chain lengths. Triple-decker stacking structures were formed via the interactions between the antiaromatic systems formed for the butoxy and dodecyloxy derivatives in the single-crystal and LC states, respectively. In particular, the LC state exhibited discotic columnar structures comprising triple deckers to exhibit high electric conductivity, as supported by molecular dynamics simulations.

2.
Minim Invasive Ther Allied Technol ; 30(1): 21-26, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31621439

RESUMEN

PURPOSE: To evaluate the usefulness of 2D-shear wave elastography (2D-SWE) in the prediction of type II endoleaks after endovascular aneurysm repair (EVAR) of abdominal aortic aneurysms (AAA). MATERIAL AND METHODS: Twenty-nine patients underwent EVAR for AAA, and 2D-SWE was performed after EVAR. Follow-up contrast-enhanced CT and ultrasonography were performed to evaluate endoleaks in all patients. The median follow-up period was 12 months (range, 3-12 months). Patients were divided into two groups: one with an endoleak (endoleak group) and another without it (control group). We compared the elasticity index (EI) of intraluminal thrombus (ITL) and fresh thrombus (FT) between the two groups. RESULTS: Type II endoleaks were confirmed in five of the 29 patients (endoleak group), and there were no endoleaks in the other 24 (control group). ILT was observed in 21 patients of the control group and in all patients of the endoleak group. There was a difference only in EI of ILT; the mean EI (± standard deviation) of ILT was 89 ± 16 kPA in the control group and 113 ± 25 kPA in the endoleak group (p=.037). CONCLUSIONS: High EI of ILT may predict the occurrence of type II endoleaks after EVAR of AAA.


Asunto(s)
Aneurisma de la Aorta Abdominal , Implantación de Prótesis Vascular , Diagnóstico por Imagen de Elasticidad , Procedimientos Endovasculares , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/cirugía , Endofuga/diagnóstico por imagen , Endofuga/etiología , Procedimientos Endovasculares/efectos adversos , Humanos , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento
3.
Jpn J Radiol ; 39(2): 159-164, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32940850

RESUMEN

PURPOSE: To evaluate whether a computer-aided vessel-suppression system improves lung nodule detection in routine clinical settings. MATERIALS AND METHODS: We used computer software that automatically suppresses pulmonary vessels on chest CT while preserving pulmonary nodules. Sixty-one chest CT images were included in our study. Three radiologists independently read either standard CT images alone or both computer-aided CT and standard CT images randomly to detect a pulmonary nodule ≥ 4 mm in diameter. After an interval of at least 15 days to avoid recall bias, the three radiologists interpreted the counterpart images of the same patients. The reference standard was decided by an expert panel. The primary endpoint was sensitivity. The secondary endpoint was interpretation time. RESULTS: The average sensitivity improved with computer-aided CT (72% for standard CT vs. 84% for computer-aided CT, p = 0.02). There was no difference in the false-positive rate (21% for both standard CT and computer-aided CT, p = 0.98). Although the average reading time was 9.5% longer for computer-aided plus standard CT compared with standard CT alone, the difference was not significant (p = 0.11). CONCLUSION: Vessel-suppressed CT images helped radiologists to improve the sensitivity of pulmonary nodule detection without compromising the false-positive rate.


Asunto(s)
Neoplasias Pulmonares/diagnóstico por imagen , Pulmón/diagnóstico por imagen , Interpretación de Imagen Radiográfica Asistida por Computador , Nódulo Pulmonar Solitario/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Pulmón/irrigación sanguínea , Masculino , Persona de Mediana Edad , Nódulos Pulmonares Múltiples/diagnóstico por imagen , Sensibilidad y Especificidad , Programas Informáticos , Tomografía Computarizada por Rayos X/métodos , Adulto Joven
4.
Chem Asian J ; 15(4): 494-498, 2020 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-31899580

RESUMEN

Anion complexes of anion-responsive π-electronic molecules can behave as pseudo π-electronic anions providing various ion pairs in combination with countercations. In this study, single crystals of ion-pairing assemblies comprising porphyrin-AuIII complexes and Cl- complexes of dipyrrolyldiketone BF2 complexes were prepared from 1:1 mixtures of anion receptors and the Cl- salts of cationic porphyrins in solution. In the solid state, the ion pairs formed characteristic assemblies, depending on the substituents of the anion receptors and porphyrin-AuIII complexes. Theoretical calculations on the ion pairs revealed that the stacking structures are stabilized by compensating positive and negative charges as well as π-π interactions.

5.
Emerg Radiol ; 26(5): 501-506, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31129737

RESUMEN

PURPOSE: To evaluate the clinical outcomes of bronchial artery embolization (BAE) using a gelatin sponge for hemoptysis from pulmonary aspergilloma and compare them with treatment outcomes for hemoptysis from other diseases. METHODS: Fifty-two patients underwent BAE using a gelatin sponge. The etiology of hemoptysis was pulmonary aspergilloma in 8 (PA group) and other diseases in 44 (control group). The technical success rate, clinical success rate, hemoptysis-free rate, and complication rate were compared between the PA group and control group. Technical success was defined as the complete cessation of the targeted feeding artery as confirmed by digital subtraction angiography, and clinical success as the cessation of hemoptysis within 24 h of BAE. Recurrent hemoptysis was defined as a single or multiple episodes of hemoptysis causing > 30 ml of bleeding per day. RESULTS: Technical and clinical success rates were 100% in both groups. Hemoptysis-free rates were 85% at 6 months and 72% at 12-60 months in the control group, and 38% at 6-12 months and 25% thereafter in the PA group (P = 0.0009). No complications were observed following BAE in any case in the two groups. CONCLUSION: BAE using a gelatin sponge may not be effective for hemoptysis from pulmonary aspergilloma.


Asunto(s)
Arterias Bronquiales , Embolización Terapéutica/métodos , Esponja de Gelatina Absorbible/uso terapéutico , Hemoptisis/microbiología , Hemoptisis/terapia , Aspergilosis Pulmonar/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Angiografía de Substracción Digital , Femenino , Hemoptisis/diagnóstico por imagen , Humanos , Enfermedades Pulmonares/complicaciones , Masculino , Persona de Mediana Edad , Aspergilosis Pulmonar/diagnóstico por imagen , Estudios Retrospectivos
6.
iScience ; 14: 241-256, 2019 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-30981960

RESUMEN

Porphyrin-AuIII complexes were found to act as π-electronic cations, which can combine with various counteranions, including π-electronic anions. Single-crystal X-ray analyses revealed the formation of assemblies with contributions of charge-by-charge and charge-segregated assemblies, depending on the geometry and electronic state of the counteranions. Porphyrin-AuIII complexes possessing aliphatic alkyl chains formed dimension-controlled ion-pairing assemblies as thermotropic liquid crystals, whose ionic components were highly organized by π-π stacking and electrostatic interactions.

7.
Chem Asian J ; 11(14): 2025-9, 2016 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-27304212

RESUMEN

Alkyl-substituted pyrrole-based anion-responsive π-electronic systems formed supramolecular gels and liquid crystals through effective π-π stacking and van der Waals interactions. The addition of chloride as a planar cation salt afforded ion-pairing assemblies as soft materials comprising planar receptor-Cl(-) complexes and the cation.

8.
Chemistry ; 22(23): 7843-50, 2016 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-27120581

RESUMEN

Pentacyanocyclopentadienide (PCCp(-) ), a stable π-electronic anion, provided various ion-pairing assemblies in combination with various cations. PCCp(-) -based assemblies exist as single crystals and mesophases owing to interionic interactions with π-electronic and aliphatic cations with a variety of geometries, substituents, and electronic structures. Single-crystal X-ray analysis revealed that PCCp(-) formed cation-dependent arrangements with contributions from charge-by-charge and charge-segregated assembly modes for ion pairs with π-electronic and aliphatic cations, respectively. Furthermore, some aliphatic cations gave dimension-controlled organized structures with PCCp(-) , as observed in the mesophases, for which synchrotron XRD analysis suggested the formation of charge-segregated modes. Noncontact evaluation of conductivity for (C12 H25 )3 MeN(+) ⋅PCCp(-) films revealed potential hole-transporting properties, yielding a local-scale hole mobility of 0.4 cm(2) V(-1) s(-1) at semiconductor-insulator interfaces.

9.
Pol J Radiol ; 80: 464-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26516390

RESUMEN

Horseshoe lung (HL) is often associated with cardiovascular malformations such as scimitar syndrome and unilateral lung hypoplasia. In patients with HL, the hypoplastic lung is almost always located on the right side. Cases of HL with a hypoplastic left lung are extremely rare. In this paper, we describe a case of a one-day-old boy with HL involving left lung hypoplasia and perform a systematic review of the literature on HL with left lung hypoplasia. Only 10 cases of HL involving left lung hypoplasia have been reported in the literature. Most of those cases also exhibited cardiovascular malformations and pulmonary hypertension. There have not been any reported cases of HL involving left lung hypoplasia associated with scimitar syndrome. HL involving left lung hypoplasia is rare and tends to be associated with pulmonary hypertension.

10.
Chem Commun (Camb) ; 50(73): 10615-8, 2014 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-25072869

RESUMEN

Because the metallophilicity of attractive Pt(II)···Pt(II) interactions helps in the fabrication of columnar structures, terpyridine-Pt(II) complexes were used as planar counter cationic species for formation of charge-segregated assemblies using π-conjugated receptor-Cl(-) complexes as planar anions.


Asunto(s)
Complejos de Coordinación/química , Platino (Metal)/química , Aniones/química , Cationes/química , Dimerización , Cristales Líquidos/química , Piridinas/química
11.
Org Lett ; 15(23): 6006-9, 2013 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-24245585

RESUMEN

Dimers of appropriately arranged anion-responsive π-conjugated moieties form helical structures by interaction with chiral anions. Terphenyl-bridged dimers of dipyrrolyldiketone boron complexes show chirality induced by binding l-amino acid anions, as observed by circular dichroism (CD) and circularly polarized luminescence (CPL). The preferred configurations of helical structures depend on the geometries of the terphenyl spacer moieties.


Asunto(s)
Compuestos de Terfenilo/química , Aniones/química , Dicroismo Circular , Cristalografía por Rayos X , Modelos Teóricos , Estructura Molecular , Polímeros/química , Estereoisomerismo
12.
Chemistry ; 19(48): 16263-71, 2013 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-24150915

RESUMEN

Anion-responsive π-conjugated compounds having chiral alkyl chains were synthesized. Circular dichroism (CD) and circularly polarized luminescence (CPL) were observed in the solution-state assemblies of the chiral anion receptors and those of their anion complexes as salts of a planar triazatriangulenium cation. The CD and CPL spectral patterns of the ion-pair-based assemblies were completely opposite to those of the anion-free assemblies, and this suggests that anion binding and subsequent ion pairing change the chirality of the assembly modes.


Asunto(s)
Aniones/síntesis química , Luminiscencia , Aniones/química , Dicroismo Circular , Iones , Modelos Químicos , Estructura Molecular
13.
J Am Chem Soc ; 135(39): 14797-805, 2013 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-24053173

RESUMEN

Oriented salts from planar charged species were prepared by combining positively and negatively charged receptor-anion complexes with similar geometries using dicationic and electronically neutral π-conjugated receptors. Phenylene- or pyrimidine-bridged bis(imidazolium) dicationic anion receptors formed monocationic receptor-Cl(-) complexes that were accompanied by a free Cl(-). This free Cl(-) was subsequently captured by pyrrole-based neutral anion receptors to form negatively charged receptor-Cl(-) complexes. The ion pair of the resulting positively and negatively charged planar receptor-Cl(-) complexes could produce a supramolecular octane gel, adopting a lamellar self-organized structure in its xerogel state. On the other hand, the solid-state ion pairs had hexagonal columnar mesophases, which formed via alternate stacking of the positively and negatively charged planar receptor-Cl(-) complexes. By use of the flash-photolysis time-resolved microwave conductivity technique, the one-dimensional charge-carrier transporting property, with a mobility of 0.05 cm(2) V(-1) s(-1), was determined for the newly prepared solid-state ion pairs.


Asunto(s)
Cloruros/química , Geles/química , Iones/química , Imidazoles/química , Modelos Moleculares , Pirimidinas/química , Pirroles/química
14.
Chem Asian J ; 8(9): 2088-95, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23813866

RESUMEN

The fusion of bowl-shaped π-conjugated corannulene units to anion-responsive π-conjugated dipyrrolyldiketone-boron complexes resulted in new molecular materials with a unique self-assembly capability. The bowl-fused receptor with aliphatic tails could form both supramolecular gels and mesophases through π-stacking interactions and also exhibited anion-responsive characteristics. The presence of the π-bowl unit not only afforded enhanced self-assembly capability both in solution and in the mesophases, as evidenced by gelation experiments and phase-transition profiles, but also enhanced intrinsic charge-carrier mobility.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos/química , Aniones/química , Boro/química , Electrones , Geles/química , Transición de Fase , Pirroles/química , Espectrofotometría Ultravioleta , Temperatura
15.
Chemistry ; 19(35): 11676-85, 2013 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-23853116

RESUMEN

Polygon-like [2+2]- and [3+3]-type metal complexes were prepared from dipyrrin dimers connected by acute-angled spacers. The electrical conduction depends strongly on the packing alignment of the compounds, revealing the presence of effective hopping pathways for holes with relatively high mobility up to 0.11 cm(2) V(-1) s(-1) along the aligned axis of [3+3]-type metal-bridged assemblies. These observations correlated with the geometrical control of the π-conjugated metal complexes in the cyclic structures, which enables their ordered arrangement in the assemblies.


Asunto(s)
Complejos de Coordinación/química , Complejos de Coordinación/síntesis química , Ligandos , Difracción de Rayos X
16.
Chem Commun (Camb) ; 49(39): 4100-13, 2013 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-23323265

RESUMEN

This article summarises recent progress in the study of acyclic oligopyrrole molecules that show anion-binding behaviours. Compared to cyclic oligopyrroles, acyclic systems have shown fascinating properties in terms of their linear geometries, as seen in the examples of biotic oligopyrroles and related analogues, which have shown the ability to transport anions across membranes. Another example of anion-responsive acyclic oligopyrroles is a dipyrrolyldiketone boron complex reported by our group. Modifications of the pyrrole rings and the boron unit of the anion-responsive molecule have resulted in the preparation of various derivatives, which showed efficient anion-binding behaviours and unique electronic and optical properties and formed assemblies in a variety of states. In this article, we mainly focus on anion-driven discrete assemblies, such as the helical structures of covalently linked oligomers and their resulting properties in the solution state.


Asunto(s)
Pirroles/química , Aniones/química , Boro/química , Cristalografía por Rayos X , Geles/química , Cetonas/química , Conformación Molecular , Teoría Cuántica
18.
Chem Commun (Camb) ; 48(17): 2301-3, 2012 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-22261686

RESUMEN

Assemblies comprising anion complexes of π-extended oligopyrrole derivatives and counter cations, as well as those of anion-free receptor molecules, exhibited the formation of mesophases based on columnar structures using electrostatic and π-π interactions.


Asunto(s)
Pirroles/química , Aniones/química , Cristalografía por Rayos X , Electrones , Conformación Molecular , Electricidad Estática
19.
Chem Commun (Camb) ; 47(29): 8241-3, 2011 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-21691669

RESUMEN

Pyrrole-based π-conjugated anion-responsive molecules bearing an anionic moiety form self-complementary dimers, which exhibit self-sorting behaviours depending on the substituted positions of anionic sites.


Asunto(s)
Aniones/química , Benzoatos/química , Boro/química , Dimerización , Cetonas/química , Pirroles/química
20.
J Am Chem Soc ; 133(24): 9266-9, 2011 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-21599014

RESUMEN

Introduction of a BINOL-boron moiety to dipyrrolyldiketones as precursors of anion-responsive π-conjugated molecules results in the formation of a chiral environment in the form of anion-free receptors and anion-binding complexes. Conformation changes by inversion (flipping) of two pyrrole rings as a result of anion binding can control the chiroptical properties of the anion receptors. In particular, appropriate pyrrole ß-substituents induce distorted receptor π-planes and, as a result, give larger circularly polarized luminescence (CPL), which can be tuned by chemical stimuli (anions). This is the first example of chemical-stimuli-responsive CPL properties.


Asunto(s)
Boro/química , Glicoles/química , Mediciones Luminiscentes , Modelos Moleculares , Conformación Molecular , Fenómenos Ópticos , Pirroles/química , Estereoisomerismo
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