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1.
Inorg Chem ; 62(35): 14152-14157, 2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37552507

RESUMEN

Chirality is a fundamental property of nature, and thus, building novel chiral molecules plays a crucial role in multidisciplinary fields. Herein, we have developed a straightforward approach to effectively incorporate all four types of point, axial, planar, and helical chiralities into a single molecule for the first time. The resultant "point-line-plane-helix" binuclear Pt(II) complexes exhibit multiple chiralities, including not only point and axial chiralities from the bridging ligands but also planar and helical chiralities from metal coordination. The intramolecular π-π and Pt-Pt interactions will restrict intramolecular rotations, thereby stabilizing the metal-induced planar and helical chiralities. Furthermore, enantiopure (R,R,R,Rp,M) or (S,S,S,Sp,P) molecules could be obtained by chirality self-sorting without the use of chiral high-performance liquid chromatography. Their single-crystal, circular dichroism, and circularly polarized luminescence properties are comprehensively investigated, providing unequivocal insights into the design of multiple-chirality materials for related applications.

2.
J Pain Res ; 16: 2393-2406, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37483407

RESUMEN

Background: Gastrointestinal (GI) endoscopy becomes more and more common now in order to diagnose and treat GI diseases, and anesthesia/sedation plays an important role. We aim to discuss the developmental trends and evaluate the research hotspots using bibliometric methods for GI endoscopy anesthesia/sedation in the past two decades. Methods: The original and review articles published from 2001 to December 2022 related to GI endoscopy anesthesia/sedation were extracted from the Web of Science database. Four different softwares (CiteSpace, VOSviewer, and Bibliometrix, Online Analysis Platform of Literature Metrology (Bibliometric)) were used for this comprehensive analysis. Results: According to our retrieval strategy, we found a total of 3154 related literatures. Original research articles were 2855, and reviews were 299. There has been a substantial increase in the research on GI endoscopy anesthesia/sedation in recent 22 years. These publications have been cited 66,418 times, with a mean of 21.04 citations per publication. The US maintained a leading position in global research, with the largest number of publications (29.94%), and China ranked second (19.92%). Keyword burst and concurrence showed that conscious sedation, colonoscopy and midazolam were the most frequently occurring keywords. Conclusion: Our research found that GI endoscopy anesthesia/sedation was in a period of rapid development and demonstrated the improvement of medical instruments and surgical options that had significantly contributed to the field of GI endoscopy anesthesia/sedation. The US dominates this field, and the selection and dosage of sedative regimens have always been the foci of disease research to improve comfort and safety, while adverse events and risks arouse attention gradually. In the past 20 years, hotspots mainly focus on upper gastrointestinal endoscopy, gastroscopy, and esophagogastroduodenoscopy. These data would provide future directions for clinicians and researchers regarding GI endoscopy anesthesia/sedation.

3.
Angew Chem Int Ed Engl ; 62(21): e202302011, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36939317

RESUMEN

PtII complexes have attracted a great deal of interest due to their rich phosphorescent properties. However, these square-planar PtII complexes are far more likely to encounter the problems of lack of metal-induced chirality and emission "aggregation-caused quenching". Herein, soft-bridged binuclear PtII complexes bearing metal-induced planar chirality were synthesized and characterized. These soft bridging ligands with smaller conjugated system would help to not only improve solubility for synthesis and enantioseparation but also introduce point chirality from amino acid for highly efficient diastereoselectivity. Furthermore, the intramolecular Pt-Pt distances could be well regulated by soft bridging ligands, and consequently the phosphorescence quantum yield up to 100 % could be achieved by shortening intramolecular Pt-Pt distance for first time. These complexes can be used as emitters in highly efficient solution-processed organic light-emitting diodes.

4.
Int J Ment Health Addict ; : 1-23, 2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36817983

RESUMEN

Cannabis is the fourth psychoactive substance to be legalized which are of far-reaching significance to the world. We analyzed data from the 2019 Global Burden of Disease Study (GBD) to estimate the incidence and prevalence of cannabis use disorder (CUD) and calculated the disease burden of CUD in 204 countries and territories and 21 regions over the past three decades. We reported disease burden due to CUD in terms of disability-adjusted life years (DALYs), age-standardized rate (ASR), estimated annual percentage change (EAPC), and analyzed associations between the burden of CUD and sociodemographic index (SDI) quintiles. Globally, the number of incidence cases of CUD was estimated to be increasing by 32.3% from 1990 to 2019 and males are nearly double higher than that of female. DALYs increase 38.6% from 1990. Young people aged 20-24 years old with cannabis use disorder have the highest DALYs in 2019, followed by those younger than 20 years old. India, Canada, USA, Qatar, Kenya, and high SDI quintile areas showed a high burden of disease. Nearly 200 million individuals are cannabis users worldwide, and CUD is a notable condition of GBD. The global cultivation of cannabis, rooted in different cultures, diversified access to cannabis, legalization in controversy, the promotion of medical cannabis, and many other factors promote the global cannabis industry is constantly updated and upgraded. It deserves more discussion in the future in terms of pathophysiological mechanisms, socioeconomics, law, and policy improvement. Supplementary Information: The online version contains supplementary material available at 10.1007/s11469-022-00999-4.

5.
J Phys Chem Lett ; 13(25): 5838-5844, 2022 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-35727022

RESUMEN

Ultralong room-temperature phosphorescence (RTP) is greatly important in a series of applications, but obtaining RTP from metal-free organic materials is still an enormous challenge due to the spin-forbidden nature of triplet excitons. Because of its electron-rich nature and easy derivatization, carbazole (Cz) is widely used to build organic RTP and thermally activated delayed fluorescence (TADF) materials. However, Liu et al. (Nat. Mater. 2021, 20, 175) recently demonstrated that the RTP of Cz is induced by charge traps of its isomeric impurity in commercial sources. Here, on the basis of the classical El-Sayed rule and the recently discovered intersystem crossing promotion principles (twisted structure and charge transfer), we designed and prepared highly pure (>99.9%) (R/S)-octahydro-binaphthyl-based bicarbazoles (BiCz) for high-performance RTP (ΦP = 23%; τp = 1.09 s). Interestingly, BiCz exhibited photoactivated TADF and RTP in isolated and aggregated states, respectively, and thus would be an efficient tool for rejuvenating Cz-based RTP.

6.
Endoscopy ; 54(2): 222, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35086156
7.
J Am Chem Soc ; 144(5): 2233-2244, 2022 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-35048693

RESUMEN

Chiral organometallic complexes have demonstrated many potential and practical applications. However, building metal-induced chirality for square-planar complexes still remains a big challenge, because their 2D planar molecular structures are usually superimposable on their mirror images. Herein, we report a straightforward and efficient way to achieve a novel kind of planar chirality by constructing 3D double-layer molecular structures. When the achiral ligand 1,3,4-oxadiazole-2-thiol (OXT) was used to bridge two square-planar complexes, a pair of racemic R/S planar-chiral binuclear Pt(II) complexes was obtained, which could be separated by chiral high-performance liquid chromatography (HPLC). Moreover, enantiopure R,R,R or S,S,S complexes could be prepared by the use of chiral (R)-/(S)-binaphthalene-derived OXT ligands in 99% diastereoselectivity without the use of chiral HPLC. The binaphthalene groups help to ensure good solubility and a smooth amorphous thin film morphology but have little effect on the photophysical properties. The resultant complexes display strong orange-red and near-infrared phosphorescence with quantum yields of up to 83.4% and can be applied as emitters in highly efficient solution-processed organic light-emitting diodes to achieve luminance, luminance efficiency, external quantum efficiency, and an asymmetry factor of up to 3.22 × 104 cd m-2, 28.7 cd A-1, 14.3%, and 2.0 × 10-3, respectively. With a comprehensive consideration of EL efficiency and the asymmetry factor, this is the best performance among Pt(II) complex based circularly polarized OLEDs. Therefore, this work provides a new and simple strategy to build planar chirality for chiroptical and circularly polarized luminescence applications.

8.
Inorg Chem ; 60(17): 13557-13566, 2021 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-34409839

RESUMEN

A new series of axially chiral binuclear Pt(II) complexes with bridging ligands of binaphthalenes and octahydro-binaphthalenes and auxiliary ligands of ß-diketones were designed and prepared. These complexes, identified by spectral and electrochemical methods and single-crystal X-ray diffraction, emit an orange-red phosphorescence with a quantum yield up to 21% and 70% in solution and solid, respectively, due to the effect of steric hindrance from bridging ligands and the 2,3-position extension of chiral axis planes. They can be used as emitters in solution-processed organic light-emitting diodes to achieve luminance efficiency, asymmetry factor, and external quantum efficiency up to 5.4 cd A-1, 3.0 × 10-3, and 3.1%, respectively. Moreover, the essential relationships between their chemical structures and luminescence quantum efficiency and asymmetry factor are discussed, which affords explicit insights for designing circularly polarized luminescent materials and devices.

9.
Chem Asian J ; 15(20): 3370-3378, 2020 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-32893975

RESUMEN

The simpler, the better. A series of simple, neutral and ultralow-molecular-weight (MW: 140-200) hydrazide-derived supramolecular gelators have been designed and synthesized in two straightforward steps. For non-conjugated cyclohexane-derived hydrazides, their monomers can self-assemble to form gels through intermolecular hydrogen bonds and dipole-dipole interactions. Significantly, conjugated phthalhydrazide can self-aggregate into planar and circular trimers through intermolecular hydrogen bonds and then self-assemble to form gels through intermolecular π-π stacking interactions. It is interesting that these simple gelators exhibit unusual properties, such as self-healing, multi-response fluorescence, and visual and selective recognition of chiral (R)/(S)-1,1'-binaphthalene-2,2'-diamine and S2- through much different times of gel re-formation and blue-green color change, respectively. These results underline the importance of supramolecular gels and extend the scope of supramolecular gelators.

10.
ACS Appl Bio Mater ; 3(10): 7236-7242, 2020 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-35019382

RESUMEN

In the present work, a chemical reaction has been performed for supramolecular gels to achieve multiple-stimuli-responsive smart soft materials. Simple chiral binaphthalene-based receptors can condense with histidine (His) to yield a Schiff base, which would help to achieve visual chiral recognition of unprotected l/d-His through gel formation along with specific selectivity toward 20 amino acids. Through intermolecular hydrogen bonds, the resultant Schiff base molecules assemble with excess His molecules to form three-dimensional (3D) networks of metastable cross-linked nanospheres and stable nanofibers in EtOH/water and MeOH/water, respectively. Significantly, this condensation reaction exhibits unique reversible and chromatic phenomena between sol-gel phase transitions in EtOH/water, which provide a way to design chemical reaction-based multivisual-change supramolecular gels for sensing and switching applications.

11.
Cureus ; 11(8): e5466, 2019 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-31523585

RESUMEN

Non-small-cell lung cancer (NSCLC) is the most common non-AIDS defining cancer in patients infected with HIV and has the highest mortality rate among all cancers in this patient population. Treatment of NSCLC in HIV-positive patients is similar to that in HIV-negative patients, but less is known about the molecular characteristics of NSCLC in HIV-positive patients. This report describes two patients with HIV-associated NSCLC and rearrangements of the anaplastic lymphoma kinase (ALK) gene. The disease followed an indolent course in both patients.

12.
Chem Commun (Camb) ; 55(66): 9873-9876, 2019 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-31364621

RESUMEN

Simple (S)- or (R)-1,1'-binaphthalene-2,2'-diol-3-carbaldehyde was found to enantioselectively self-assemble to form a gel or solution with one enantiomer of chiral amines, 1,1'-binaphthalene-2,2'-diamine, through intermolecular hydrogen bond, HH, π-π stacking, and chirality-induced interactions. The enantioselective recognition is visual and highly selective with little interference from similar organic compounds and common cations and anions.

13.
Dalton Trans ; 48(13): 4420-4428, 2019 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-30865737

RESUMEN

A series of binuclear cyclometalated Pt(ii) complexes with the bridge ligand of binaphthyl quinoline were synthesized and characterized. Owing to the restriction of intramolecular motions in chiral binaphthyl linkers, the complexes exhibited two unusual metal-induced chiral components and aggregation-induced red phosphorescence. The (R,R,R)/(S,S,S) enantiopure complexes that were confirmed by X-ray diffraction, circular dichroism spectra, time-dependent density functional theory calculations, and circularly polarized luminescence did not require purification by chiral high-performance liquid chromatography and could yield unique 1D M or P hierarchical helices of helices via intermolecular noncovalent interactions. Moreover, it is the first time that racemization-induced phosphorescence enhancement has been observed.

14.
ACS Omega ; 3(8): 8992-9002, 2018 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-31459032

RESUMEN

Fluorescent organic materials are commonly π-conjugated planar molecules. In the present work, however, we report a novel class of nonconjugated fluorescent molecular cages of trinuclear fluoroborate complexes (nine samples) with salicylaldehyde-based Schiff base ligands. Owing to the stress from lone pair electrons of N atom in the triethylamine bridge, these B(III) complexes exhibit unusual enantiomers with a tripodlike side-single-opening structure. They emit blue, green, and red emission with large Stokes shifts (up to 159 nm) and high fluorescence quantum yields in both solution (up to 0.24) and solid state (up to 0.25), which might contribute to their strong intramolecular hydrogen bonds and weak intermolecular and intramolecular π-π interactions. Combining their advantages of nonconjugation and biocompatibility, these flexible complexes have potential applications in living cell imaging and anion hosts. We have examined the inherent relationships between their chemical structures and emission properties and afforded a new stage for the design of nonconjugated fluorescent fluoroborate complexes.

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