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1.
BMC Pregnancy Childbirth ; 24(1): 325, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38671408

RESUMO

BACKGROUND: Congenital heart disease (CHD) is the predominant birth defect. This study aimed to explore the association between maternal cardiovascular health (CVH) and the CHD risk in offspring. METHODS: We used the prospective data from the Fujian Birth Cohort Study, collected from March 2019 to December 2022 on pregnant women within 14 weeks of gestation. Overall maternal CVH was assessed by seven CVH metrics (including physical activity, smoking, sleep duration, body mass index, blood pressure, total cholesterol, and fasting plasma glucose), with each metric classified as ideal, intermediate or poor with specific points. Participants were further allocated into high, moderate and low CVH categories based on the cumulative CVH score. The association with offspring CHD was determined with log-binominal regression models. RESULTS: A total of 19810 participants aged 29.7 (SD: 3.9) years were included, with 7846 (39.6%) classified as having high CVH, 10949 (55.3%) as having moderate CVH, and 1015 (5.1%) as having low CVH. The average offspring CHD rate was 2.52%, with rates of 2.35%, 2.52% and 3.84% across the high, moderate and low CVH categories, respectively (P = 0.02). Adjusted relative risks (RRs) of having offspring CHD were 0.64 (95% CI: 0.45-0.90, P = 0.001) for high CVH and 0.67 (95% CI: 0.48-0.93, P = 0.02) for moderate CVH compared to low CVH. For individual metrics, only ideal total cholesterol was significantly associated with lower offspring CHD (RR: 0.73, 95% CI: 0.59-0.83, P = 0.002). CONCLUSIONS: Pregnant women of high or moderate CVH categories in early pregnancy had reduced risks of CHD in offspring, compared to those of low CVH. It is important to monitor and improve CVH during pre-pregnancy counseling and early prenatal care.


Assuntos
Cardiopatias Congênitas , Humanos , Feminino , Gravidez , Cardiopatias Congênitas/epidemiologia , Adulto , Estudos Prospectivos , China/epidemiologia , Fatores de Risco , Coorte de Nascimento , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Saúde Materna/estatística & dados numéricos , Complicações Cardiovasculares na Gravidez/epidemiologia
2.
Small ; 19(32): e2303069, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37165759

RESUMO

Amination of aryl chlorides by metallaphotocatalysis is highly desired but remains practically challenging. Meanwhile, relying on soluble noble-metal photocatalysts suffers from resource scarcity and structural instability which limit their practical application. Here in, a highly crystalline acetylene-based hydrazone-linked covalent organic framewok-1 (AC-COF-1) is reported that enables metallaphotocatalytic amination of aryl chlorides. The non-planar effect of hydrazone linkage and weak interlayer attraction of acetylene bond are minimized by intralayer hydrogen-bonding. As a result, the COF shows not only improved crystallinity and porosity, but also enhanced optical and electronic properties compared to a COF analog without hydrogen-bonding. Notably, dual AC-COF-1/Ni system affords CN coupling products from broad aryl chloride substrates in excellent yields (up to 99%) and good functional tolerance. Furthermore, AC-COF-1 is recoverable and reusable for seven times photocatalysis cycles. This report demonstrates simple approach to tune the structure-activity relationship in COFs at molecular level.

3.
Acc Chem Res ; 55(16): 2316-2325, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35916446

RESUMO

In past decades, regular porous architectures have received a great amount of attention because of their versatile functions and applications derived from their efficient adsorption of various guests. However, most reported porous architectures exist only in the solid state. Therefore, their applications as biomaterials may face several challenges, such as phase separation, slow degradation, and long-term accumulation in the body. This Account summarizes our efforts with respect to the development and biomedical applications of water-soluble 3D diamondoid supramolecular organic frameworks (dSOFs), a family of supramolecular polymers that possess intrinsic regular nanoscale porosity.dSOFs have been constructed from tetratopic components and cucurbit[8]uril (CB[8]) through hydrophobically driven encapsulation by CB[8] for intermolecular dimers formed by peripheral aromatic subunits of the tetratopic components in water. All dSOFs exhibit porosity regularity or periodicity in aqueous solution, which is confirmed by solution-phase synchrotron SAXS and XRD experiments. Dynamic light scattering (DLS) reveals that their sizes range from 50 to 150 nm, depending on the concentrations of the components. As nonequilibrium supramolecular architectures, dSOFs can maintain their nanoscale sizes at micromolar concentrations for dozens of hours. Their diamondoid pores have aperture sizes ranging from 2.1 to 3.6 nm, whereas their water solubility and porosity regularity allow them to rapidly include discrete guests driven by ion-pair electrostatic attraction, hydrophobicity, or a combination of the two interactions. The guests may be small molecule or large macromolecular drugs, photodynamic agents (PDAs), or DNA.The rapid inclusion of bioactive guests into dSOFs has led to two important biofunctions. The first is to function as antidotes through including residual drugs. For heparins, the inclusion results in full neutralization of their anticoagulant activity. For clinically used porphyrin PDAs, the inclusion can alleviate their long-term posttreatment phototoxicity but does not reduce their photodynamic efficacy. The second is to function as in situ loading carriers for the intracellular delivery of antitumor drugs or DNA. Their nanoscale sizes bring out their ability to overcome the multidrug resistance of tumor cells, which leads to a remarkable enhancement of the bioactivity of the included drugs. By conjugating aldoxorubicin to tetrahedral components, albumin-mimicking prodrugs have also been constructed, which conspicuously improves the efficacy of aldoxorubicin toward multi-drug-resistant tumors through the delivery of the frameworks. As new supramolecular drugs and carriers, dSOFs are generally biocompatible. Thus, further efforts might lead to medical benefits in the future.


Assuntos
Nanoporos , Água , Polímeros , Espalhamento a Baixo Ângulo , Difração de Raios X
4.
J Org Chem ; 88(13): 8522-8531, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37303203

RESUMO

[1n]Paracyclophane has been known for nearly 40 years, but its derivatives and properties are understudied in comparison to those of other macrocyclic compounds. By the modification of pillar[5]arene, we successfully obtained five electron-rich pentagonal macrocycles (pseudo[n]-pillar[5]arenes, n = 1-4) with the decrease of substituted phenylenes one after another, achieving the partial derivatization of [15]paracyclophane skeleton at its phenylene sites. Pseudo[n]-pillar[5]arenes (P[n]P[5]s) served as a kind of macrocyclic host to form complexes with various guests, such as dinitriles, dihaloalkanes, and imidazolium salt, in a 1:1 host-guest stoichiometric ratio. The binding constants with the guest gradually reduce along the decrease of substituted phenylene segments from host P[1]P[5] to P[4]P[5]. It is worthy to note that P[n]P[5]s can adjust their conformations to the "pillar-like" shape effectively when binding with succinonitrile in the solid state.


Assuntos
Compostos Macrocíclicos , Compostos Macrocíclicos/química , Conformação Molecular
5.
Chem Soc Rev ; 51(2): 434-449, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-34931205

RESUMO

Porous organic polymers (POPs) have attracted increasing attention and emerged as a new research area in polymer chemistry. During the past decade, the intense desirability for application in aqueous scenarios has spawned the development of a specific class of POPs, i.e., water-soluble or dispersible porous organic polymers (WS-POPs) that can allow the implementation of porosity-based functions in aqueous media. In this Tutorial Review, aiming at providing a practical guide to this area, we will discuss recent advances in the preparation of WS-POPs through covalent/dynamic covalent, coordination and supramolecular approaches. As a result of their intrinsic and well-defined porosity, diverse topological architectures as well as unique water-processable features, many water-soluble/dispersible POPs have been demonstrated to exhibit potential for various applications, which include drug, DNA and protein delivery, bioimaging, photocatalysis, explosive detection and membrane separation. We will also highlight the related function of the representative structures. Finally, we provide our perspective for the future research, with a focus on the development of new structures and biofunctions.


Assuntos
Preparações Farmacêuticas , Polímeros , Porosidade , Água
6.
Int J Mol Sci ; 24(9)2023 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-37175406

RESUMO

Sensitive systems with controlled release of drugs or diagnostic markers are attractive for solving the problems of biomedicine and antitumor therapy. In this study, new decasubstituted pillar[5]arene derivatives containing L-Tryptophan and L-Phenylalanine residues have been synthesized as pH-responsive drug nanocarriers. Fluorescein dye (Fluo) was loaded into the pillar[5]arene associates and used as a spectroscopic probe to evaluate the release in buffered solutions with pH 4.5, 7.4, and 9.2. The nature of the substituents in the pillar[5]arene structure has a huge influence on the rate of delivering. When the dye was loaded into the associates based on pillar[5]arene derivatives containing L-Tryptophan, the Fluo release occurs in the neutral (pH = 7.4) and alkaline (pH = 9.2) buffered solutions. When the dye was loaded into the associates based on pillar[5]arene with L-Phenylalanine fragments, the absence of release was observed in every pH evaluated. This happens as the result of different packing of the dye in the structure of the associate. This fact was confirmed by different fluorescence mechanisms (aggregation-caused quenching and aggregation-induced emission) and association constants. It was shown that the macrocycle with L-Phenylalanine fragments binds the dye more efficiently (lgKa = 3.92). The experimental results indicate that the pillar[5]arene derivatives with amino acids fragments have a high potential to be used as a pH-responsive drug delivery devices, especially for promoting the intracellular delivering, due to its nanometric size.


Assuntos
Nanopartículas , Triptofano , Fluoresceína , Fenilalanina , Nanopartículas/química
7.
Phys Rev Lett ; 129(22): 220402, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36493448

RESUMO

Topological vacua are a family of degenerate ground states of Yang-Mills fields with zero field strength but nontrivial topological structures. They play a fundamental role in particle physics and quantum field theory, but have not yet been experimentally observed. Here we report the first theoretical proposal and experimental realization of synthetic topological vacua with a cloud of atomic Bose-Einstein condensates. Our setup provides a promising platform to demonstrate the fundamental concept that a vacuum, rather than being empty, has rich spatial structures. The Hamiltonian for the vacuum of topological number n=1 is synthesized and the related Hopf index is measured. The vacuum of topological number n=2 is also realized, and we find that vacua with different topological numbers have distinctive spin textures and Hopf links. Our Letter opens up opportunities for exploring topological vacua and related long-sought-after instantons in tabletop experiments.


Assuntos
Teoria Quântica
8.
Chemistry ; 28(36): e202200914, 2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35474522

RESUMO

Selective preparation of two-dimensional polymers (2DPs) and supramolecular polymers (2DSPs) with defined thickness is crucially important for controlling and maximizing their functions, yet it has remained as a synthetic challenge. In the past decade, several approaches have been developed to allow selective preparation of discrete monolayer 2DPs and 2DSPs. Recently, crystal exfoliation and self-assembly strategies have been employed to successfully prepare bilayer 2DP and 2DSP, which represent the first step towards the controlled "growth" of 2D polymers from the thinnest monolayers to thicker few-layers along the third dimension. This Concept review discusses the concept of accurate synthesis of 2D polymers with defined layers. Advances in this research area will pave the way to rational synthetic strategies for 2D polymers with controlled thickness.


Assuntos
Polímeros , Polímeros/química
9.
Mol Pharm ; 19(3): 953-962, 2022 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-35102736

RESUMO

Bacterial lipopolysaccharides (LPS, endotoxins) cause sepsis that is responsible for a huge amount of mortality globally. However, their neutralization or detoxification remains an unmet medical need. We envisaged that cationic organic frameworks with persistent hydrophobic porosity may adsorb and thus neutralize LPS through a combination of cooperative ion-pairing electrostatic attraction and hydrophobicity. We here report the preparation of two water-soluble flexible organic frameworks (FOF-1 and FOF-2) from tetratopic and ditopic precursors through quantitative formation of hydrazone bonds at room temperature. The two FOFs are revealed to possess hydrodynamic diameters, which range from 20 to 120 nm, depending on the concentrations. Dynamic light scattering and isothermal titration calorimetric and chromogenic limulus amebocyte lysate experiments indicate that both frameworks are able to adsorb and thus reduce the concentration of free LPS molecules in aqueous solution, whereas cytokine inhibition experiments with RAW264.7 support that this adsorption can significantly decrease the toxicity of LPS. In vivo experiments with mice (five males per group) show that the injection of FOF-1 at a dose of 0.6 mg/kg realizes the survival of all of the mice administrated with LPS of the d-galactosamine (d-Gal)-sensitized absolute lethal dose (LD100, 0.05 mg/kg), whereas its maximum tolerated dose for mice is determined to be 10 mg/kg. These findings provide a new promising sequestration strategy for the development of porous agents for the neutralization of LPS.


Assuntos
Endotoxinas , Lipopolissacarídeos , Adsorção , Animais , Cátions , Lipopolissacarídeos/química , Camundongos , Porosidade , Água
10.
Phys Rev Lett ; 126(1): 017702, 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33480777

RESUMO

Monopoles play a center role in gauge theories and topological matter. There are two fundamental types of monopoles in physics: vector monopoles and tensor monopoles. Examples of vector monopoles include the Dirac monopole in three dimensions and Yang monopole in five dimensions, which have been extensively studied and observed in condensed matter or artificial systems. However, tensor monopoles are less studied, and their observation has not been reported. Here we experimentally construct a tunable spin-1 Hamiltonian to generate a tensor monopole and then measure its unique features with superconducting quantum circuits. The energy structure of a 4D Weyl-like Hamiltonian with threefold degenerate points acting as tensor monopoles is imaged. Through quantum-metric measurements, we report the first experiment that measures the Dixmier-Douady invariant, the topological charge of the tensor monopole. Moreover, we observe topological phase transitions characterized by the topological Dixmier-Douady invariant, rather than the Chern numbers as used for conventional monopoles in odd-dimensional spaces.

11.
Phys Rev Lett ; 127(13): 136802, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34623865

RESUMO

The topology of quantum systems has become a topic of great interest since the discovery of topological insulators. However, as a hallmark of the topological insulators, the spin Chern number has not yet been experimentally detected. The challenge to directly measure this topological invariant lies in the fact that this spin Chern number is defined based on artificially constructed wave functions. Here we experimentally mimic the celebrated Bernevig-Hughes-Zhang model with cold atoms, and then measure the spin Chern number with the linear response theory. We observe that, although the Chern number for each spin component is ill defined, the spin Chern number measured by their difference is still well defined when both energy and spin gaps are nonvanished.

12.
J Org Chem ; 86(5): 3943-3951, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33599126

RESUMO

Two organic cages have been prepared in situ in water through the 2 + 3 hydrazone coupling of two pyridinium-derived trialdehydes and oxalohydrazide. The highly water-soluble cages encapsulate and solubilize linear neutral molecules. Such encapsulation has been applied for the promotion of both two- or three-component hydrazone condensation in water. For two-component reactions, the yields of the resulting monohydrazones are increased from 5-10 to 90-96%. For three-component reactions of hydrazinecarbohydrazide with 11 aromatic aldehydes, in the presence of the organic cages, the bihydrazone products can be produced in 88-96% yields. In contrast, without the promotion of the organic cages, 9 of the reactions do not afford the corresponding dihydrazone product.

13.
J Am Chem Soc ; 142(7): 3577-3582, 2020 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-32011130

RESUMO

Four water-soluble hydrazone-based three-dimensional (3D) flexible organic frameworks FOF-1-4 have been synthesized from a semirigid tetracationic tetraaldehyde and four flexible dihydrazides. 1H NMR spectroscopy indicated the quantitative formation of FOF-1-4 in D2O, while dynamic light scattering experiments revealed that, depending on the concentration, these porous frameworks display hydrodynamic diameters ranging from 50 to 120 nm. The porosity of the frameworks is confirmed by ethanol vapor adsorption experiments of the solid samples as well as the high loading capacity for a 2.3 nm porphyrin guest in water. The new water-soluble frameworks exhibit low cytotoxicity and form inherent pores with diameters of 5.3 or 6.7 nm, allowing rapid inclusion of proteins such as bovine serum albumin and green and orange fluorescent proteins, and efficient delivery of the proteins into normal and cancer cells. Flow cytometric analysis reveals percentages of the delivered cells up to 99.8%.


Assuntos
Estruturas Metalorgânicas/química , Proteínas/química , Etanol/química , Hidrazonas/química , Ressonância Magnética Nuclear Biomolecular , Espalhamento de Radiação , Solubilidade , Espectrofotometria Infravermelho , Água/química
15.
Phys Rev Lett ; 122(21): 210401, 2019 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31283314

RESUMO

A Berry curvature is an imaginary component of the quantum geometric tensor (QGT) and is well studied in many branches of modern physics; however, the quantum metric as a real component of the QGT is less explored. Here, by using tunable superconducting circuits, we experimentally demonstrate two methods to directly measure the quantum metric tensor for characterizing the geometry and topology of underlying quantum states in parameter space. The first method is to probe the transition probability after a sudden quench, and the second one is to detect the excitation rate under weak periodic driving. Furthermore, based on quantum metric and Berry-curvature measurements, we explore a topological phase transition in a simulated time-reversal-symmetric system. The work opens up a unique approach to explore the topology of quantum states with the QGT.

16.
Angew Chem Int Ed Engl ; 58(1): 226-230, 2019 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-30426629

RESUMO

Halogen bonding has been used to glue together hydrogen-bonded short arylamide foldamers to achieve new supramolecular double and quadruple helices in the solid state. Three compounds, which bear a pyridine at one end and either a CF2 I or fluorinated iodobenzene group at the other end, engage in head-to-tail N⋅⋅⋅I halogen bonds to form one-component supramolecular P and M helices, which stack to afford supramolecular double-stranded helices. One of the double helices can dimerize to form a G-quadruplex-like supramolecular quadruple helix. Another symmetric compound, which bears a pyridine at each end, binds to ICF2 CF2 I through N⋅⋅⋅I halogen bonds to form two-component supramolecular P and M helices, with one turn consisting of four (2+2) molecules. Half of the pyridine-bearing molecules in two P helices and two M helices stack alternatingly to form another supramolecular quadruple helix. Another half of the pyridine-bearing molecules in such quadruple helices stack alternatingly with counterparts from neighboring quadruple helices, leading to unique quadruple helical arrays in two-dimensional space.

17.
Small ; 14(24): e1801037, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29767476

RESUMO

Enrichment of molecular photosensitizers and catalysts in a confined nanospace is conducive for photocatalytic reactions due to improved photoexcited electron transfer from photosensitizers to catalysts. Herein, the self-assembly of a highly stable 3D supramolecular organic framework from a rigid bipyridine-derived tetrahedral monomer and cucurbit[8]uril in water, and its efficient and simultaneous intake of both [Ru(bpy)3 ]2+ -based photosensitizers and various polyoxometalates, that can take place at very low loading, are reported. The enrichment substantially increases the apparent concentration of both photosensitizer and catalyst in the interior of the framework, which leads to a recyclable, homogeneous, visible light-driven photocatalytic system with 110-fold increase of the turnover number for the hydrogen evolution reaction.

18.
Phys Rev Lett ; 120(13): 130503, 2018 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-29694203

RESUMO

We experimentally explore the topological Maxwell metal bands by mapping the momentum space of condensed-matter models to the tunable parameter space of superconducting quantum circuits. An exotic band structure that is effectively described by the spin-1 Maxwell equations is imaged. Threefold degenerate points dubbed Maxwell points are observed in the Maxwell metal bands. Moreover, we engineer and observe the topological phase transition from the topological Maxwell metal to a trivial insulator, and report the first experiment to measure the Chern numbers that are higher than one.

19.
Opt Express ; 25(14): 15786-15795, 2017 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-28789091

RESUMO

We reveal a novel topological property of the exceptional points in a two-level parity-time symmetric system and then propose a scheme to detect the topological exceptional points in the system, which is embedded in a larger Hilbert space constructed by a four-level cold atomic system. We show that a tunable parameter in the presented system for simulating the non-Hermitian Hamiltonian can be tuned to sweep the eigenstates through the exceptional points in parameter space. The non-trivial Berry phases of the eigenstates obtained in this loop from the exceptional points can be measured by the atomic interferometry. Since the proposed operations and detection are experimentally feasible, our scheme may pave a promising way to explore the novel properties of non-Hermitian systems.

20.
Macromol Rapid Commun ; 38(15)2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28570767

RESUMO

Conjugated polymers may be induced by intra- and/or intermolecular non-covalent forces to fold into helical conformations. Helices formed by aromatic amide, hydrazide, and urea polymers possess a well-organized cavity and depth, which is defined by their degree of polymerization. Driving forces may be intramolecular hydrogen bonding and/or solvophobicity, or guest induction. The resulting long helices represent a new class of unimacromolecular dynamic tubular architectures that exhibit unique properties or functions in, for example, molecular recognition, chirality transfer, and ion transporting. The recent advances are highlighted here.


Assuntos
Amidas/química , Ligação de Hidrogênio , Conformação Molecular , Polimerização , Polímeros
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