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1.
Anal Chem ; 96(15): 5741-5745, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38573003

RESUMO

Fucosylation is an important structural feature of glycans and plays an essential role in the regulation of glycoprotein functions. Fucosylation can be classified into core- (CF) and antenna-fucosylation (AF, also known as (sialyl-) Lewis) based on the location on N-glycans, and they perform distinct biological functions. In this study, core- and antenna-fucosylated N-glycans on human serum glycoproteins that hold great clinical application values were systematically characterized at the site-specific level using StrucGP combined with the recently developed fucosylation assignment method. The results showed that fucosylation was widely distributed on serum glycoproteins, with 50% of fucosylated glycopeptides modified by AF N-glycans, 37% by CF N-glycans, and 13% by dual-fucosylated N-glycans. Interestingly, CF and AF N-glycans preferred to modify different groups of serum glycoproteins with different tissue origins and were involved in distinctive biological processes. Specifically, AF N-glycoproteins are mainly from the liver and participated in complement activation, blood coagulation, and endopeptidase activities, while CF N-glycoproteins originate from diverse tissues and are mainly involved in cell adhesion and signaling transduction. These data further enhanced our understanding of fucosylation on circulation glycoproteins.


Assuntos
Glicoproteínas , Fígado , Humanos , Glicoproteínas/química , Glicosilação , Fígado/metabolismo , Polissacarídeos/química , Fucose/química
2.
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
3.
J Stroke Cerebrovasc Dis ; 33(4): 107638, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38360250

RESUMO

OBJECTIVE: To assess the longitudinal evolution of cerebral perfusion after revascularization surgery in patients with moyamoya disease (MMD) by CT perfusion (CTP). MATERIALS AND METHODS: Thirty-one clinically confirmed MMD patients (12 males and 19 females, average age: 33.26 y, Suzuki stages 3 and 4: 19 and 11, respectively) who underwent revascularization surgery (bilateral (n=13) or unilateral (n=18)) were studied retrospectively. All patients underwent CTP examinations before and in the week after surgery and long-term (>3 months). CTP metrics (CBF, CBV, MTT, TTP, and delay TTP) were derived. The corresponding CTP metric values of the ROIs, which were manually drawn in the white matter (WM) and gray matter (GM), were recorded. RESULTS: Six patients developed a new or progressive cerebral infarction/hemorrhage. In all patients, compared with the preoperative level, the TTP of GM and WM decreased in the short term after the surgery (P ≤ 0.005). Concurrently, the WM CBF increased significantly a week after surgery (P =0.02). However, in the long-term follow-up, the CBV and CBF in the GM and WM decreased to equal to or lower than the preoperative level, especially for CBV in the WM (P =0.012). Furthermore, cerebral perfusion began to decrease in the sixth month, and a continuous decline was observed over the next two months. It returned to the presurgical level after one year. In addition, the improvement in postsurgical perfusion was greater in Suzuki stage 3 patients than stage 4 patients. CONCLUSION: Cerebral perfusion in patients with MMD improved shortly after surgery. However, in the long-term, brain perfusion decreased, most seriously in 6-8 months postoperatively, which might indicate that patients with MMD need timely follow-up and long-term intervention.


Assuntos
Revascularização Cerebral , Doença de Moyamoya , Masculino , Feminino , Humanos , Adulto , Doença de Moyamoya/diagnóstico por imagem , Doença de Moyamoya/cirurgia , Estudos Retrospectivos , Perfusão , Hemorragia Cerebral , Tomografia Computadorizada por Raios X , Circulação Cerebrovascular , Revascularização Cerebral/efeitos adversos
4.
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.

5.
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
6.
Anal Biochem ; 680: 115318, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37696464

RESUMO

Normal liquefaction of semen is one of the key steps to ensure the smooth progress of fertilization, and glycosylation has been reported to be involved in the whole process of fertilization. Till now, it is still unclear whether and how glycosylation changes during the liquefaction process of semen. In this study, by performing a glycoproteomic analysis of human semen with the liquefaction process (liquefaction time of semen: 0 min vs 30 min) using our recently developed StrucGP software combined with the Tandem Mass Tags (TMT) based quantification, we identified 25 intact glycopeptides (IGPs) from 10 glycoproteins in semen that were significantly changed during liquefaction, including 23 up-regulated and two down-regulated. Among the 23 up-regulated glycopeptides, half were modified with sialylated glycans, suggesting that sialylated glycans may play a key role in the semen liquefaction process. The data provide an invaluable resource for further studies on the role of glycosylation during semen liquefaction.


Assuntos
Líquidos Corporais , Sêmen , Humanos , Glicopeptídeos , Glicosilação , Polissacarídeos
7.
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
8.
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
9.
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
10.
Microb Pathog ; 162: 105085, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34252554

RESUMO

OBJECTIVES: The type VI secretion system (T6SS) in Klebsiella pneumoniae strains isolated from the bloodstream, intestinal, the pyogenic liver abscess has been reported. Here we aimed to characterize T6SS in 248 Klebsiella pneumoniae isolates with all kinds of specimens from a Chinese hospital and to investigate the potential association of T6SS with virulence and drug resistance. METHODS: T6SS genes, capsular serotyping genes, drug resistance genes, and virulence genes were identified by polymerase chain reaction (PCR). Antibiotic susceptibilities were examined by the disk diffusion method. To assess biofilm formation of these clinical Klebsiella pneumoniae isolates, 96-well microtiter plate assays were performed. MLST was used to analyze the genotypes of these Klebsiella pneumoniae isolates. RESULTS: The frequency of T6SS genes among the clinical Klebsiella pneumoniae isolates was 72.2%. The T6SS-positive isolates displayed higher resistance to piperacillin-tazobactam, ciprofloxacin, levofloxacin, meropenem than the T6SS-negative isolates (P < 0.05). The T6SS-positive isolates formed significantly more biofilm mass than the T6SS-negative isolates (mean ± standard deviation [SD], 0.3 ± 0.09 vs.0.16 ± 0.06; P < 0.01). Compared to the T6SS-negative isolates, the T6SS-positive isolates had a higher frequency of virulence genes (rmpA, fimH, entB, kfu, ybtS) and the pLVPK-like plasmid (P < 0.05). CONCLUSION: In conclusion, the prevalence of the type VI secretion system is high in clinical Klebsiella pneumoniae isolates in a Chinese teaching hospital. T6SS-positive strains show higher biofilm-forming activity with high drug resistance and exhibit higher virulence potential.


Assuntos
Infecções por Klebsiella , Sistemas de Secreção Tipo VI , China , Resistência a Medicamentos , Hospitais , Humanos , Klebsiella pneumoniae/genética , Tipagem de Sequências Multilocus , Virulência/genética , Fatores de Virulência/genética
11.
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
12.
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
13.
Glycoconj J ; 39(6): 737-745, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36322335

RESUMO

Intrahepatic cholangiocarcinoma (ICC) is the second major subtype of primary liver cancer and has caused more and more attention with increasing incidence and mortality worldwide. Our previous study found that bisecting N-glycans are commonly increased in ICC, while the effects and potential functions of bisecting GlcNAc in ICC are still largely unclear. In this study, we further confirmed that the structures of bisecting GlcNAc were significantly up-regulated in ICC compared with paracancer tissues by glycoproteomic data and lectin histochemistry. The expression of its glycosyltransferase MGAT3 was also up-regulated in ICC tissues at both mRNA and protein levels, and expression of MGAT3 is negatively correlated with overall survival explored by bioinformatic analyses and published datasets from 255 patients. Next, the silencing of MGAT3 could inhibit the growth and invasion of ICC cells, and overexpressing of MGAT3 only promoted ICC cell invasion. Further glycoproteomic analysis showed that the commonly glycoproteins modified by bisecting GlcNAc after MGAT3-overexpression in two ICC cell lines were mainly involved in cell movement-related biological processes, such as cell adhesion, integrin-related and ECM-receptor interaction. This study sheds light on the potential effects of bisecting GlcNAc in ICC cells and suggests that MGAT3 might be used as a potential target in the therapy of ICC.


Assuntos
Acetilglucosamina , N-Acetilglucosaminiltransferases , Humanos , N-Acetilglucosaminiltransferases/genética , N-Acetilglucosaminiltransferases/metabolismo , Acetilglucosamina/metabolismo , Polissacarídeos/química , Glicoproteínas/genética , Glicoproteínas/química , Linhagem Celular , Linhagem Celular Tumoral
14.
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
15.
Anal Bioanal Chem ; 414(29-30): 8245-8253, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36181511

RESUMO

Selecting proper and efficient glycopeptide enrichment approaches are essential for mass spectrometry-based glycoproteomics since glycopeptides are usually with microheterogeneity and low abundance in most biological samples. Herein, we introduced a cotton hydrophilic interaction liquid chromatography (HILIC) approach for large-scale glycopeptide enrichment with 80% acetonitrile/1% trifluoroacetic acid as the optimal sample loading buffer. The comparison of cotton HILIC with Venusil HILIC and mixed anion-exchange (MAX) approaches indicated that cotton HILIC was superior in overall glycopeptide enrichment, whereas Venusil HILIC preferred in complex glycan structures and MAX performed better with high mannose glycans. Exploration of capacity and recovery rate of cotton HILIC illustrated that 5mg cotton packed in a 200µL tip achieved a reasonable glycopeptide enrichment performance (~6% recovery) from ~0.5mg peptides. In conclusion, cotton HILIC can be used as an optional glycopeptide enrichment approach in glycosylation analysis with its specific merit.


Assuntos
Glicopeptídeos , Polissacarídeos , Glicopeptídeos/química , Cromatografia Líquida/métodos , Glicosilação , Interações Hidrofóbicas e Hidrofílicas
16.
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.

17.
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.

18.
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.

19.
J Craniofac Surg ; 32(2): e167-e171, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33705062

RESUMO

ABSTRACT: The calcifying epithelial odontogenic tumor (CEOT) is a rare benign odontogenic tumor, which usually presents with distension of affected tissues. Radiologically, the lesions are often associated with an unerupted tooth and may have spot calcification shadows. The authors report a case of a CEOT in a 48-year-old male involving the right mandibular jaw bone and mentum soft tissues. The authors performed hemimandibulectomy and enucleation followed by reconstruction of the mandible using a vascularized free fibular flap through a digital surgical technique in order to restore the patient's facial symmetry and prepare the area for functional restorations. The case illustrates who the free fibular flap graft can be used for satisfactory mandibular reconstruction and restoration of the morphology and functions.


Assuntos
Retalhos de Tecido Biológico , Neoplasias Mandibulares , Reconstrução Mandibular , Tumores Odontogênicos , Neoplasias Cutâneas , Fíbula/cirurgia , Humanos , Masculino , Neoplasias Mandibulares/diagnóstico por imagem , Neoplasias Mandibulares/cirurgia , Pessoa de Meia-Idade , Tumores Odontogênicos/diagnóstico por imagem , Tumores Odontogênicos/cirurgia
20.
J Stroke Cerebrovasc Dis ; 30(7): 105845, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33964546

RESUMO

PURPOSE: This study aims to test the validity of a new quantitative scoring instrument-the Venous Occlusion Image Score (VOIS), and assess the diagnostic and prognostic value of VOIS for cerebral venous sinus thrombosis (CVST). METHODS: The VOIS divided the major cerebral venous sinuses and internal jugular veins into nine parts of interest. CT venography and DSA source images and reconstruction were extracted from the database, then interpreted and scored independently according to VOIS by a panel of three reviewers. Inter-observer and intra-observer reliability were determined using the intraclass correlation coefficient (ICC) and the kappa coefficient (κ). The primary outcome was the 3-month functional outcome and evaluated by modified Rankin Scale (mRS). The sensitivity and specificity of VOIS for the primary outcomes were computed. Logistic regression was applied to evaluate the association between the score on VOIS and the primary outcomes. RESULTS: Fifty-six patients with CVST were included in the study. For 16 patients underwent cerebral CTV and DSA, excellent interobserver agreement was observed for DSA (ICC=0.90, 95%CI = 0.87 - 0.92, P < 0.001), and CTV (ICC = 0.92, 95%CI = 0.84 - 0.93, P < 0.001). The κ coefficient of agreement for the two radiology measures was 0.88 (95%CI = 0.79-0.92), indicating good inter-method agreement. For 56 patients followed up by CTV, baseline VOIS value correlated inversely with the severity of stroke on the National Institutes of Health Stroke Scale (r = -0·53, P < 0·001), and modified Rankin Scale (r = -0·59, P < 0·001). Baseline CTV-VOIS value predicted functional outcome (P < 0·05). CONCLUSION: VOIS may serve as a convenient and reliable method in the treatment guidance and outcome prediction of patients with CVST.


Assuntos
Angiografia Cerebral , Veias Cerebrais/diagnóstico por imagem , Angiografia por Tomografia Computadorizada , Tomografia Computadorizada Multidetectores , Flebografia , Trombose dos Seios Intracranianos/diagnóstico por imagem , Adulto , Bases de Dados Factuais , Avaliação da Deficiência , Feminino , Humanos , Masculino , Variações Dependentes do Observador , Valor Preditivo dos Testes , Prognóstico , Interpretação de Imagem Radiográfica Assistida por Computador , Reprodutibilidade dos Testes , Estudos Retrospectivos , Índice de Gravidade de Doença , Trombose dos Seios Intracranianos/fisiopatologia , Trombose dos Seios Intracranianos/terapia , Adulto Jovem
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