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1.
Int Wound J ; 21(4): e14798, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38572761

RESUMO

To systematically evaluate the effects of quality nursing care on wound pain and anxiety in burn patients. Computerised searches of PubMed, Google Scholar, Cochrane Library, Embase, Wanfang, China Biomedical Literature Database and China National Knowledge Infrastructure databases randomised controlled trials (RCTs) on the application of quality nursing care to burn patients were carried out from database inception to October 2023. Literature was screened and evaluated by two researchers based on inclusion and exclusion criteria, and data were extracted from the final included literature. Stata 17.0 software was employed for data analysis. Overall, 15 RCTs and 1115 burn patients were included, including 563 and 552 in the quality care and routine care groups. It was found that, compared with routine care, burn patients who implemented quality care had significantly less wound pain (SMD: -1.79, 95% CI: -2.22 to -1.36, p < 0.001), anxiety (SMD: -2.71. 95% CI: -3.49 to -1.92, p < 0.001) and depression (SMD: -1.74, 95% CI: -2.35 to -1.14, p < 0.001) levels were significantly reduced post-trauma.


Assuntos
Ansiedade , Queimaduras , Humanos , Ansiedade/etiologia , Transtornos de Ansiedade , Dor , Queimaduras/complicações , Queimaduras/terapia , China , Ensaios Clínicos Controlados Aleatórios como Assunto
2.
Angew Chem Int Ed Engl ; : e202402621, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443314

RESUMO

The incorporation of pentagon-heptagon pairs into helical nanographenes lacks a facile synthetic route, and the impact of these pairs on chiroptical properties remains unclear. In this study, a method for the stepwise construction of pentagon-heptagon pairs in helical nanographenes by the dehydrogenation of [6]helicene units was developed. Three helical nanographenes containing pentagon-heptagon pairs were synthesized and characterized using this approach. A wide variation in the molecular geometries and photophysical properties of these helical nanographenes was observed, with changes in the helical length of these structures and the introduction of the pentagon-heptagon pairs. The embedded pentagon-heptagon pairs reduced the oxidation potential of the synthesized helical nanographenes. The high isomerization energy barriers enabled the chiral resolution of the helicene enantiomers. Chiroptical investigations revealed remarkably enhanced circularly polarized luminescence and luminescence dissymmetry factors with an increasing number of the pentagon-heptagon pairs.

3.
J Am Chem Soc ; 145(35): 19333-19337, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37638550

RESUMO

The conventional approach toward molecules with large two-photon absorption (TPA) involves donor-acceptor conjugation. Herein we show a new strategy involving the use of hexa-branched nanographenes. We synthesized two hexa-branched nanographenes, one with six benzoaceanthrylene arms fused to the coronene core and the other with six pyrenyl arms fused to the coronene core. Neither of these hexa-branched nanographenes has a donor-acceptor structure, yet they exhibited high TPA values of 3.6 × 103 and 1.9 × 104 GM, respectively, which are the highest values recorded for heteroatom-free hydrocarbon molecules. Theoretical analysis suggests that the fused branched structures are responsible for the large TPA cross-section. These findings illustrate the importance of the topology of the fused conjugated skeleton in TPA and provide an alternative structural design toward large TPA.

4.
J Am Chem Soc ; 145(5): 2815-2821, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36705468

RESUMO

The synthesis of well-defined nanocarbon multilayers, beyond the bilayer structure, is still a challenging goal. Herein, two trilayer nanographenes were synthesized by covalently linking nanographene layers through helicene bridges. The structural characterization of the trilayer nanographenes revealed a compact trilayer-stacked architecture. The introduction of a furan ring into the helicene linker modulates the interlayer overlap and π-conjugation of the trilayer nanographenes, enabling the tuning of the interlayer coupling, as demonstrated by optical, electrochemical, and theoretical analyses. Both synthesized trilayer nanographenes are rigid chiral nanocarbons and show a chirality transfer from the helicene moiety to the stacked nanographene layers. These helical trilayer nanographenes reported here represent the covalently linked multilayer nanographenes rather than bilayer ones, showing the tunable multilayer stacking structure.

5.
Angew Chem Int Ed Engl ; 62(4): e202216193, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36413379

RESUMO

The precision synthesis of helical bilayer nanographenes (NGs) with new topology is of substantial interest because of their exotic physicochemical properties. However, helical bilayer NGs bearing non-hexagonal rings remain synthetically challenging. Here we present the efficient synthesis of the first helical bilayer nonbenzenoid nanographene (HBNG1) from a tailor-made azulene-embedded precursor, which contains a novel [10]helicene backbone with two embedded heptagons. Single-crystal X-ray analysis reveals its highly twisted bilayer geometry with a record small interlayer distance of 3.2 Šamong the reported helical bilayer NGs. Notably, the close interlayer distance between the two layers offers intramolecular through-space conjugation as revealed by in situ spectroelectrochemistry studies together with DFT simulations. Furthermore, the chiroptical properties of the P/M enantiomers of HBNG1 are also evaluated by circular dichroism and circularly polarized luminescence.

6.
Angew Chem Int Ed Engl ; 61(38): e202210268, 2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-35899409

RESUMO

Nanographenes are inclined to assemble into stacked columnar structures that are stabilized by π-π interactions, whereas other supramolecular structures of nanographenes, such as prisms and cages, are rarely investigated. Herein, a diazananographene was synthesized, and then assembled with a coordination unit, thereby producing a triangular metallaprism. After adding C60 or C70 , the triangular metallaprism was transformed into a square tetramer, which encapsulated a pair of C60 or C70 molecules. The formed host-guest complex demonstrated efficient energy transfer from the diazananographene shell to the C60 cores. The emission intensity of the capsulated C60 was enhanced remarkably, compared with free C60 , due to an increased quantum yield and optical absorption coefficient. This work demonstrates the versatility of nanographene-based supramolecular architectures beyond columnar stacking and their ability to enhance the emission of otherwise non-emissive fullerene.

7.
Adv Sci (Weinh) ; 9(19): e2105034, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35038238

RESUMO

Although water-soluble graphene quantum dots (GQDs) have shown various promising bio-applications due to their intriguing optical and chemical properties, the large heterogeneity in compositions, sizes, and shapes of these GQDs hampers the better understanding of their structure-properties correlation and further uses in terms of large-scale manufacturing practices and safety concerns. It is shown here that a water-soluble atomically-precise GQD (WAGQD-C96 ) is synthesized and exhibits a deep-red emission and excellent sonodynamic sensitization. By decorating sterically hindered water-soluble functional groups, WAGQD-C96 can be monodispersed in water without further aggregation. The deep-red emission of WAGQD-C96 facilitates the tracking of its bio-process, showing a good cell-uptake and long-time retention in tumor tissue. Compared to traditional molecular sonosensitizers, WAGQD-C96 generates superior reactive oxygen species and demonstrates excellent tumor inhibition potency as an anti-cancer sonosensitizer in in vivo studies. A good biosafety of WAGQD-C96 is validated in both in vitro and in vivo assays.


Assuntos
Grafite , Neoplasias , Pontos Quânticos , Grafite/química , Neoplasias/terapia , Pontos Quânticos/química , Água/química
8.
Angew Chem Int Ed Engl ; 60(21): 11814-11818, 2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-33751785

RESUMO

Here, we report a facile method to synthesize a series of macrocycles with different conformations. The planar macrocycle dimer (1), twisted macrocycle trimer (2) and "figure-eight" tetramer (3) are clearly elucidated by X-ray single-crystal analysis, in which the electron-rich phenanthrene units offer the possibility of supramolecular assembly. As expected, in the solid state, 1 and 3 assemble into a columnar stack and an interlocking dimer, respectively, via π-π interactions between the phenanthrene units. Compared to the rigid conformation of dimer 1, the structure of tetramer 3 is more flexible due to its enlarged ring size. 3 can deform from a figure-eight into a boat-shaped geometry to host a planar electron-deficient guest using its electron-rich phenanthrene units. When assembled with spherical electron-deficient C60 , interestingly, 3 further undergoes a conformational transformation from a figure-eight to a belt shape in order to host C60 . These supramolecular assembly behaviors of 3 demonstrate that it is an adaptable macrocyclic host for both planar molecules and fullerenes.

9.
Angew Chem Int Ed Engl ; 59(47): 20868-20872, 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-32749018

RESUMO

The radial conjugated π-system of cycloparaphenylenes (CPPs) makes them intriguing fluorophores and unique supramolecular hosts. However, the bright photoluminescence (PL) of CPPs was limited to the blue light and the supramolecular assembly behavior of large CPPs was rarely investigated. Here we present the synthesis of tetra-benzothiadiazole-based [12]cycloparaphenylene (TB[12]CPP), which exhibits a lime to orange PL with an excellent quantum yield up to 82 % in solution. The PL quantum yield of TB[12]CPP can be further improved to 98 % in polymer matrix. Benefiting from its enlarged size, TB[12]CPP can accommodate a fullerene derivative or concave-convex complexes of fullerene and buckybowl through the combined π-π and C-H⋅⋅⋅π interactions. The latter demonstrates the first case of a ternary supramolecule of CPPs.

10.
Nat Commun ; 11(1): 3976, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32769970

RESUMO

Quintulene, a non-graphitic cycloarene with fivefold symmetry, has remained synthetically elusive due to its high molecular strain originating from its curved structure. Here we report the construction of extended quintulene, which was unambiguously characterized by mass and NMR spectroscopy. The extended quintulene represents a naturally curved nanocarbon based on its conical molecular geometry. It undergoes dimerization in solution via π-π stacking to form a metastable, but isolable bilayer complex. Thermodynamic and kinetic characterization reveals the dimerization process as entropy-driven and following second-order kinetics with a high activation energy. These findings provide a deeper understanding of the assembly of conical nanocarbons. Comparison of optical properties of monomer and dimer points toward a H-type interlayer coupling in the dimer.

11.
Sci Adv ; 6(9): eaay8541, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32158946

RESUMO

The electronic structure of bilayer graphene can be altered by creating defects in its carbon skeleton. However, the natural defects are generally heterogeneous. On the other hand, rational bottom-up synthesis offers the possibility of building well-defined molecular cutout of defect-containing bilayer graphene, which allows defect-induced modulation with atomic precision. Here, we report the construction of a molecular defect-containing bilayer graphene (MDBG) with an inner cavity by organic synthesis. Single-crystal x-ray diffraction, mass spectrometry, and nuclear magnetic resonance spectroscopy unambiguously characterize the structure of MDBG. Compared with its same-sized, defect-free counterpart, the MDBG exhibits a notable blue shift of optical absorption and emission, as well as a 9.6-fold brightening of its photoluminescence, which demonstrates that a single defect can markedly alter the optical properties of bilayer graphene.

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