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1.
Mol Psychiatry ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740879

RESUMO

Non-invasive brain stimulation therapy for autism spectrum disorder (ASD) has shown beneficial effects. Recently, we and others demonstrated that visual sensory stimulation using rhythmic 40 Hz light flicker effectively improved cognitive deficits in mouse models of Alzheimer's disease and stroke. However, whether rhythmic visual 40 Hz light flicker stimulation can ameliorate behavioral deficits in ASD remains unknown. Here, we show that 16p11.2 deletion female mice exhibit a strong social novelty deficit, which was ameliorated by treatment with a long-term 40 Hz light stimulation. The elevated power of local-field potential (LFP) in the prefrontal cortex (PFC) of 16p11.2 deletion female mice was also effectively reduced by 40 Hz light treatment. Importantly, the 40 Hz light flicker reversed the excessive excitatory neurotransmission of PFC pyramidal neurons without altering the firing rate and the number of resident PFC neurons. Mechanistically, 40 Hz light flicker evoked adenosine release in the PFC to modulate excessive excitatory neurotransmission of 16p11.2 deletion female mice. Elevated adenosine functioned through its cognate A1 receptor (A1R) to suppress excessive excitatory neurotransmission and to alleviate social novelty deficits. Indeed, either blocking the A1R using a specific antagonist DPCPX or knocking down the A1R in the PFC using a shRNA completely ablated the beneficial effects of 40 Hz light flicker. Thus, this study identified adenosine as a novel neurochemical mediator for ameliorating social novelty deficit by reducing excitatory neurotransmission during 40 Hz light flicker treatment. The 40 Hz light stimulation warrants further development as a non-invasive ASD therapeutics.

2.
J Chem Inf Model ; 64(8): 3047-3058, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38520328

RESUMO

Covalent drugs exhibit advantages in that noncovalent drugs cannot match, and covalent docking is an important method for screening covalent lead compounds. However, it is difficult for covalent docking to screen covalent compounds on a large scale because covalent docking requires determination of the covalent reaction type of the compound. Here, we propose to use deep learning of a lateral interactions spiking neural network to construct a covalent lead compound screening model to quickly screen covalent lead compounds. We used the 3CL protease (3CL Pro) of SARS-CoV-2 as the screen target and constructed two classification models based on LISNN to predict the covalent binding and inhibitory activity of compounds. The two classification models were trained on the covalent complex data set targeting cysteine (Cys) and the compound inhibitory activity data set targeting 3CL Pro, respected, with good prediction accuracy (ACC > 0.9). We then screened the screening compound library with 6 covalent binding screening models and 12 inhibitory activity screening models. We tested the inhibitory activity of the 32 compounds, and the best compound inhibited SARS-CoV-2 3CL Pro with an IC50 value of 369.5 nM. Further assay implied that dithiothreitol can affect the inhibitory activity of the compound to 3CL Pro, indicating that the compound may covalently bind 3CL Pro. The selectivity test showed that the compound had good target selectivity to 3CL Pro over cathepsin L. These correlation assays can prove the rationality of the covalent lead compound screening model. Finally, covalent docking was performed to demonstrate the binding conformation of the compound with 3CL Pro. The source code can be obtained from the GitHub repository (https://github.com/guzh970630/Screen_Covalent_Compound_by_LISNN).


Assuntos
Proteases 3C de Coronavírus , Simulação de Acoplamento Molecular , Redes Neurais de Computação , SARS-CoV-2 , Proteases 3C de Coronavírus/metabolismo , Proteases 3C de Coronavírus/antagonistas & inibidores , Proteases 3C de Coronavírus/química , SARS-CoV-2/enzimologia , SARS-CoV-2/efeitos dos fármacos , Humanos , Descoberta de Drogas , Antivirais/farmacologia , Antivirais/química , Antivirais/metabolismo , Inibidores de Proteases/farmacologia , Inibidores de Proteases/química , Inibidores de Proteases/metabolismo , Tratamento Farmacológico da COVID-19 , Aprendizado Profundo , Ligação Proteica , COVID-19/virologia
3.
Nano Lett ; 23(7): 2839-2845, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36975717

RESUMO

The emergence of intrinsic quantum anomalous Hall (QAH) insulators with a long-range ferromagnetic (FM) order triggers unprecedented prosperity for combining topology and magnetism in low dimensions. Built upon atom-thin Chern insulator monolayer MnBr3, we propose that the topologically nontrivial electronic states can be systematically tuned by inherent magnetic orders and external electric/optical fields in stacked Chern insulator bilayers. The FM bilayer illustrates a high-Chern-number QAH state characterized by both quantized Hall plateaus and specific magneto-optical Kerr angles. In antiferromagnetic bilayers, Berry curvature singularity induced by electrostatic fields or lasers emerges, which further leads to a novel implementation of the layer Hall effect depending on the chirality of irradiated circularly polarized light. These results demonstrate that abundant tunable topological properties can be achieved in stacked Chern insulator bilayers, thereby suggesting a universal routine to modulate d-orbital-dominated topological Dirac fermions.

4.
Hippocampus ; 33(7): 862-871, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36709413

RESUMO

Perineuronal nets (PNNs) which mostly surround the parvalbumin (PV) neurons, have been shown to play critical roles in neural plasticity. Recently, PNNs have been shown to regulate fear-associated memory, but the molecular mechanism is still unclear. In this study, we found that removal of PNNs in vivo using chondroitinase ABC (ChABC) injection resulted in reduced firing rate of PV neurons and decreased inhibitory synaptic transmission in both PV neurons and excitatory neurons in the CA1 hippocampus. Interestingly, altered synaptic transmission appears to be mediated by presynaptic changes. Furthermore, ChABC treatment disrupts long-term contextual fear memory retention. These results suggest PNNs might alter fear memory by reducing the presynaptic GABA release.


Assuntos
Matriz Extracelular , Neurônios , Neurônios/metabolismo , Matriz Extracelular/metabolismo , Hipocampo/metabolismo , Parvalbuminas/metabolismo , Medo , Ácido gama-Aminobutírico
5.
Respir Res ; 24(1): 202, 2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37592245

RESUMO

Right heart failure is the leading cause of death in pulmonary hypertension (PH), and echocardiography is a commonly used tool for evaluating the risk hierarchy of PH. However, few studies have explored the dynamic changes in the structural and functional changes of the right heart during the process of PH. Previous studies have found that pulmonary circulation coupling right ventricular adaptation depends on the degree of pressure overload and other factors. In this study, we performed a time-dependent evaluation of right heart functional changes using transthoracic echocardiography in a SU5416 plus hypoxia (SuHx)-induced PH rat model. Rats were examined in 1-, 2-, 4-, and 6-week using right-heart catheterization, cardiac echocardiography, and harvested heart tissue. Our study found that echocardiographic measures of the right ventricle (RV) gradually worsened with the increase of right ventricular systolic pressure, and right heart hypofunction occurred at an earlier stage than pulmonary artery thickening during the development of PH. Furthermore, sarco-endoplasmic reticulum calcium ATPase 2 (SERCA2), a marker of myocardial damage, was highly expressed in week 2 of SuHx-induced PH and had higher levels of expression of γ-H2AX at all timepoints, as well as higher levels of DDR-related proteins p-ATM and p53/p-p53 and p21 in week 4 and week 6. Our study demonstrates that the structure and function of the RV begin to deteriorate with DNA damage and cellular senescence during the early stages of PH development.


Assuntos
Insuficiência Cardíaca , Hipertensão Pulmonar , Animais , Ratos , Hipertensão Pulmonar/induzido quimicamente , Hipertensão Pulmonar/diagnóstico por imagem , Proteína Supressora de Tumor p53 , Insuficiência Cardíaca/induzido quimicamente , Insuficiência Cardíaca/diagnóstico por imagem , Ecocardiografia , Dano ao DNA , Hipóxia/complicações
6.
Phys Rev Lett ; 131(3): 036701, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37540870

RESUMO

A realistic first-principle-based spin Hamiltonian is constructed for the type-II multiferroic NiI_{2}, using a symmetry-adapted cluster expansion method. Besides single ion anisotropy and isotropic Heisenberg terms, this model further includes the Kitaev interaction and a biquadratic term, and can well reproduce striking features of the experimental helical ground state, that are, e.g., a proper screw state, canting of rotation plane, propagation direction, and period. Using this model to build a phase diagram, it is demonstrated that, (i) the in-plane propagation direction of ⟨11[over ¯]0⟩ is determined by the Kitaev interaction, instead of the long-believed exchange frustrations and (ii) the canting of rotation plane is also dominantly determined by Kitaev interaction, rather than interlayer couplings. Furthermore, additional Monte Carlo simulations reveal three equivalent domains and different topological defects. Since the ferroelectricity is induced by spins in type-II multiferroics, our work also implies that Kitaev interaction is closely related to the multiferroicity of NiI_{2}.

7.
J Natl Compr Canc Netw ; 21(10): 1050-1057.e13, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37856197

RESUMO

BACKGROUND: More than 50% of patients with lung cancer are admitted to the hospital while receiving treatment, which is a burden to patients and the healthcare system. This study characterizes the risk factors and outcomes of patients with lung cancer who were admitted to the hospital. METHODS: A multidisciplinary oncology care team conducted a retrospective medical record review of patients with lung cancer admitted in 2018. Demographics, disease and admission characteristics, and end-of-life care utilization were recorded. Following a multidisciplinary consensus review process, admissions were determined to be either "avoidable" or "unavoidable." Generalized estimating equation logistic regression models assessed risks and outcomes associated with avoidable admissions. RESULTS: In all, 319 admissions for 188 patients with a median age of 66 years (IQR, 59-74 years) were included. Cancer-related symptoms accounted for 65% of hospitalizations. Common causes of unavoidable hospitalizations were unexpected disease progression causing symptoms, chronic obstructive pulmonary disease exacerbation, and infection. Of the 47 hospitalizations identified as avoidable (15%), the median overall survival was 1.6 months compared with 9.7 months (hazard ratio, 2.07; 95% CI, 1.34-3.19; P<.001) for unavoidable hospitalizations. Significant reasons for avoidable admissions included cancer-related pain (P=.02), hypervolemia (P=.03), patient desire to initiate hospice services (P=.01), and errors in medication reconciliation or distribution (P<.001). Errors in medication management caused 26% of the avoidable hospitalizations. Of admissions in patients receiving immunotherapy (n=102) or targeted therapy (n=44), 9% were due to adverse effects of treatment. Patients receiving immunotherapy and targeted therapy were at similar risk of avoidable hospitalizations compared with patients not receiving treatment (P=.3 and P=.1, respectively). CONCLUSIONS: We found that 15% of hospitalizations among patients with lung cancer were potentially avoidable. Uncontrolled symptoms, delayed implementation of end-of-life care, and errors in medication reconciliation were associated with avoidable inpatient admissions. Symptom management tools, palliative care integration, and medication reconciliations may mitigate hospitalization risk.


Assuntos
Neoplasias Pulmonares , Humanos , Pessoa de Meia-Idade , Idoso , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/terapia , Estudos Retrospectivos , Hospitalização , Cuidados Paliativos , Hospitais
8.
Respir Res ; 23(1): 314, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36376948

RESUMO

BACKGROUND: Pregnant women with pulmonary hypertension (PH) have higher mortality rates and poor foetal/neonatal outcomes. Tools to assess these risk factors are not well established. METHODS: Predictive and prognostic nomograms were constructed using data from a "Development" cohort of 420 pregnant patients with PH, recorded between January 2009 and December 2018. Logistic regression analysis established models to predict the probability of adverse maternal and foetal/neonatal events and overall survival by Cox analysis. An independent "Validation" cohort comprised data of 273 consecutive patients assessed from January 2019 until May 2022. Nomogram performance was evaluated internally and implemented with online software to increase the ease of use. RESULTS: Type I respiratory failure, New York Heart Association functional class, N-terminal pro-brain natriuretic peptide [Formula: see text] 1400 ng/L, arrhythmia, and eclampsia with pre-existing hypertension were independent risk factors for maternal mortality or heart failure. Type I respiratory failure, arrhythmia, general anaesthesia for caesarean section, New York Heart Association functional class, and N-terminal pro-brain natriuretic peptide [Formula: see text] 1400 ng/L were independent predictors of pulmonary hypertension survival during pregnancy. For foetal/neonatal adverse clinical events, type I respiratory failure, arrhythmia, general anaesthesia for caesarean section, parity, platelet count, fibrinogen, and left ventricular systolic diameter were important predictors. Nomogram application for the Development and Validation cohorts showed good discrimination and calibration; decision curve analysis demonstrated their clinical utility. CONCLUSIONS: The nomogram and its online software can be used to analyse individual mortality, heart failure risk, overall survival prediction, and adverse foetal/neonatal clinical events, which may be useful to facilitate early intervention and better survival rates.


Assuntos
Insuficiência Cardíaca , Hipertensão Pulmonar , Insuficiência Respiratória , Humanos , Recém-Nascido , Feminino , Gravidez , Nomogramas , Hipertensão Pulmonar/diagnóstico , Cesárea , Prognóstico , Estudos Retrospectivos
9.
Phys Rev Lett ; 128(1): 015702, 2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-35061482

RESUMO

The temporal characters of laser-driven phase transition from 2H to 1T^{'} has been investigated in the prototype MoTe_{2} monolayer. This process is found to be induced by fundamental electron-phonon interactions, with an unexpected phonon excitation and coupling pathway closely related to the nonequilibrium relaxation of photoexcited electrons. The order-to-order phase transformation is dissected into three substages, involving energy and momentum scattering processes from optical (A_{1}^{'} and E^{'}) to acoustic phonon modes [LA(M)] in subpicosecond timescale. An intermediate metallic state along the nonadiabatic transition pathway is also identified. These results have profound implications on nonequilibrium phase engineering strategies.

10.
Eur Arch Otorhinolaryngol ; 279(11): 5207-5214, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35438345

RESUMO

OBJECTIVE: To detect the expression of Epac1 and Epac2 in the inner ear of guinea pigs and its association with microcirculation in the inner ear. METHODS: The temporal bones of 30 healthy red-eye guinea pigs (60 ears) weighing 200-350 g were collected, then the surrounding bone wall of the cochlea was removed under a dissection microscope. Real-time quantitative PCR (RT-qPCR) and Western blot were used to detect mRNA and protein expression, respectively, of Epac1 and Epac2 in the inner ear and to compare their expression in heart, liver, kidney, intestine, and lung tissues. The specimens of the cochlea included the stria vascularis, basilar membrane, saccule, and utricles isolated under a microscope to detect the localization of Epac1 and Epac2 proteins in various parts of the inner ear through immunofluorescence staining. RESULTS: The RT-qPCR and Western blot results showed that Epac1 mRNA was universally expressed in the inner ear, heart, liver, kidneys, intestines, and lungs, and was highly expressed in the liver, kidneys, and intestines (p < 0.05 vs heart, liver, kidney, intestine; p > 0.05 vs lung). Epac2 mRNA was expressed in the inner ear and heart, but not in the liver, kidneys, intestines, or lungs (p < 0.05 vs Heart). Epac1 and Epac2 proteins were both expressed in the inner ear, heart, liver, kidneys, intestines, and lungs. The relative expression of Epac1 proteins in the inner ear was significantly different from the liver, kidneys, intestines, and lungs (p < 0.05). The relative expression of Epac2 proteins in the inner ear was significantly different from the liver, kidneys, and lungs (p < 0.05), but not from the heart (p = 0.127) or intestines (p = 0.274). Immunofluorescence staining observed under confocal microscopy indicated that Epac1 and Epac2 proteins were expressed in the stria vascularis, basilar membrane, saccule, and utricles of the inner ear. They were expressed in maginal cells, intermediate cells, and basal cells of the stria vascularis, and highly expressed in capillary endothelial cells. CONCLUSIONS: Epac1 and Epac2 mRNA and proteins were both expressed in the inner ear of guinea pigs and evenly expressed in the spiral ganglion, basilar membrane, saccule, and utricles. However, their expression in capillary endothelial cells of the stria vascularis was more obvious, suggesting that cyclic adenosine monophosphate-Epac1 signaling may play an important role in maintaining the function of the blood-labyrinth barrier and regulating the stability of microcirculation in the inner ear.


Assuntos
Cóclea , Células Endoteliais , Monofosfato de Adenosina , Animais , Membrana Basilar , Cobaias , RNA Mensageiro
11.
Chem Biodivers ; 19(4): e202200055, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35229447

RESUMO

In this study, chemical profiles for two co-existing deep-sea-derived Penicillium fungal strains were thoroughly investigated. Two new compounds and 11 known compounds were identified from Penicillium sp. LXY140-R, while one new compound and 12 known compounds were isolated from Penicillium sp. LXY140-3. Their structures were elucidated by extensive 1D and 2D NMR experiments, which were supported by HR-ESI-MS data. The antiproliferative activities of all isolates against HCT-116, A549 and Bel-7402 cell lines were also evaluated. Compounds 2, 5, 6, 10 and 13 showed potent antiproliferative activity. To reveal the metabolic relationship of the two strains, we conducted co-culture experiments to discover cross-talk molecules by a device that allows only small molecule to communicate. Extensive HPLC/MS2 experiments were applied to identify the disturbance of the chemical profiles within the synthetic Penicillium-Penicillium community. The fungal strain LXY140-R was found to accumulate mono or multiple-acetylation derivatives of deoxynivalenol (DON) sesquiterpenes as responsible molecules by the disturbance of the metabolites produced by the LXY140-3 strain.


Assuntos
Antineoplásicos , Penicillium , Antineoplásicos/química , Técnicas de Cocultura , Fungos , Estrutura Molecular , Penicillium/química , Metabolismo Secundário
12.
Exp Cell Res ; 387(1): 111755, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31812471

RESUMO

OBJECTIVE: The aim of this study is to establish the dexamethasone sodium phosphate multivesicular liposomes thermosensative hydrogel (DEX-MVLs-Gel) drug delivery system and to analyze the pharmacodynamics, pharmacokinetics and safety of DEX-MVLs-Gel as well as to explore whether the prepared DEX-MVLs-Gel can protect the hearing in the guinea pigs following noise exposure. METHODS: DEX-MVLs formulations were constructed by double emulsion method, and the DEX-MVLs-Gel was prepared after adding P407 and P188 into the DEX-MVLs. A total of 20 adult albino guinea pigs were chosen to establish the animal models with noise-induced hearing loss. After animals were treated with DEX-MVLs-Gel at concentrations of 20, 6 and 2 mg/mL, and 5 mg/mL Dexamethasone Sodium Phosphate (DEX-P) solution, respectively, the hearing function, drug concentration in the peripheral lymph fluid, and hair cell morphology were assessed. RESULTS: The ABR threshold of the 20 mg/mL DEX-MVLs-Gel treated group at the frequencies of 4, 8, 16 and 24 kHz were measured as 47.5 ± 5.2, 48.3 ± 4.1, 55.8 ± 3.8 and 57.5 5 ± 5.2 dB SPL, respectively. Statistical significances were noted between the 20 mg/mL DEX-MVLs-Gel treated group and control group at each frequency (all P < 0.05), between the 2 mg/mL and 6 mg/mL DEX-MVLs-Gel treated groups at the frequencies of 4 and 8 kHz (both P < 0.05). High Performance Liquid Chromatography (HPLC) demonstrated that the drug concentrations in the peripheral lymph in all groups were gradually decreased on the 1st, 3rd and 7th d after intratympanic injection. Scattered hair cell loss could be observed mainly in the basal and middle turn in the saline administrated group and the 20 mg/mL DEX-MVLs-Gel administration group, and the hair cell loss was not identified in the apical turn. CONCLUSIONS: A high concentration (20 mg/mL) of DEX-MVLs-Gel exerts significant protective effects upon the guinea pigs with noise-induced hearing loss. The prepared DEX-MVLs-Gel can be effectively maintained in the peripheral lymph fluid of guinea pigs for 3-7 d and MVLs-Gel causes no obvious ototoxicity.


Assuntos
Dexametasona/análogos & derivados , Perda Auditiva Provocada por Ruído/tratamento farmacológico , Hidrogéis/química , Hidrogéis/farmacologia , Lipossomos/química , Animais , Dexametasona/química , Dexametasona/farmacologia , Cobaias , Modelos Animais
13.
Nano Lett ; 19(9): 6323-6329, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31431010

RESUMO

Two-dimensional topological materials have attracted intense research efforts owing to their promise in applications for low-energy, high-efficiency quantum computations. Group-VA elemental thin films with strong spin-orbit coupling have been predicted to host topologically nontrivial states as excellent two-dimensional topological materials. Herein, we experimentally demonstrated for the first time that the epitaxially grown high-quality antimonene monolayer islands with buckled configurations exhibit significantly robust one-dimensional topological edge states above the Fermi level. We further demonstrated that these topologically nontrivial edge states arise from a single p-orbital manifold as a general consequence of atomic spin-orbit coupling. Thus, our findings establish monolayer antimonene as a new class of topological monolayer materials hosting the topological edge states for future low-power electronic nanodevices and quantum computations.

14.
Eur Arch Otorhinolaryngol ; 276(3): 665-672, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30604056

RESUMO

PURPOSE: The aims of the present study are to investigate the variations in clinical features, including medical history, hearing function, vestibular function, and degree of endolymphatic hydrops (EH), in Meniere's disease (MD) patients with and without drop attacks (DAs), and to examine the efficacy of intratympanic gentamicin (ITG) treatment in alleviating DAs. METHODS: In total, 177 unilateral definite MD patients, including 16 patients with DAs and 161 patients without DAs, were enrolled. The results of hearing test, vestibular-evoked myogenic potentials (VEMPs), and magnetic resonance imaging (MRI) were analyzed. Thirteen patients with DAs received a single ITG treatment and were followed up. RESULTS: The disease course of MD in the DA group was significantly longer than that in the control group (p = 0.007). MD patients with DAs had significantly greater hearing loss and worse EH than MD patients without DAs (p < 0.05). However, there was no between-group difference in vestibular function. In the study, 92.31% of refractory definite MD patients with DAs achieved satisfactory control of DAs after ITG treatment. CONCLUSIONS: MD patients with DAs tend to suffer from severe hearing loss and a significant degree of EH in the inner ear. However, the vestibular function of MD patients with DAs may not be completely abolished, but be sensitive to stimulating signals. ITG treatment, which helps to decrease vestibular sensitivity, was an effective treatment to control DAs.


Assuntos
Hidropisia Endolinfática/etiologia , Gentamicinas/uso terapêutico , Perda Auditiva/etiologia , Doença de Meniere/complicações , Síncope/tratamento farmacológico , Síncope/etiologia , Adulto , Estudos de Casos e Controles , Feminino , Gentamicinas/administração & dosagem , Audição , Testes Auditivos , Humanos , Injeção Intratimpânica , Imageamento por Ressonância Magnética , Masculino , Doença de Meniere/fisiopatologia , Pessoa de Meia-Idade , Potenciais Evocados Miogênicos Vestibulares , Vestíbulo do Labirinto
15.
Mikrochim Acta ; 187(1): 46, 2019 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-31838593

RESUMO

A fluorometric assay is described for ochratoxin A (OTA) using an aptamer. The method is based on exonuclease-assisted recycling amplification. The OTA-binding aptamer partially hybridizes with complementary DNA (cDNA) that is released when the aptamer recognizes OTA. Then, cDNA hybridizes with a specifically designed hairpin DNA. Next, short ssDNA and cDNA are, respectively, released by exonuclease III catalyzed hydrolysis of the dsDNA. The cDNA induces the next ring opening and digestion. The short ssDNA captures the sDNA that is labeled with fluorescent FAM and is absorbed on graphene oxide (GO). The green fluorescence of the sDNA/GO system is quenched but is recovered if the sDNA is released from GO. This assay is high sensitive, works in the 5 nM to 200 nM OTA concentration range and has a 0.96 nM lower detection limit. It was applied to the quantitation of OTA in spiked wine and coffee samples. Graphical abstractSchematic of a fluorometric assay based on exonuclease-assisted recycling amplification for quantitative monitoring of OTA without the need of sample separation and multiple washing steps.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais , Técnicas Eletroquímicas , Exodesoxirribonucleases/química , Fluorometria , Técnicas de Amplificação de Ácido Nucleico , Ocratoxinas/análise , Exodesoxirribonucleases/metabolismo , Humanos , Ocratoxinas/metabolismo , Tamanho da Partícula , Propriedades de Superfície
16.
Molecules ; 24(10)2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-31137573

RESUMO

The programmed cell death ligand protein 1 (PD-L1) is a member of the B7 protein family and consists of 290 amino acid residues. The blockade of the PD-1/PD-L1 immune checkpoint pathway is effective in tumor treatment. Results: Two pharmacophore models were generated based on peptides and small molecules. Hypo 1A consists of one hydrogen bond donor, one hydrogen bond acceptor, two hydrophobic points and one aromatic ring point. Hypo 1B consists of one hydrogen bond donor, three hydrophobic points and one positive ionizable point. Conclusions: The pharmacophore model consisting of a hydrogen bond donor, hydrophobic points and a positive ionizable point may be helpful for designing small-molecule inhibitors targeting PD-L1.


Assuntos
Peptídeos/farmacologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/farmacologia , Humanos , Concentração Inibidora 50 , Simulação de Acoplamento Molecular , Receptor de Morte Celular Programada 1/metabolismo , Curva ROC , Reprodutibilidade dos Testes
18.
BMC Cancer ; 18(1): 783, 2018 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-30075764

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is among the deadliest cancers due to its heterogeneity, contributing to chemoresistance and recurrence. Cancer stem-like cells (CSCs) are suggested to play an important role in HCC tumorigenesis. This study investigates the role of Wnt/ß-catenin pathway in CSC enrichment and the capabilities of these CSCs in tumor initiation in orthotopic immunocompetent mouse model. METHODS: HCC-CSCs were enriched using established serum-free culture method. Wnt/ß-catenin pathway activation and its components were analyzed by western blot and qRT-PCR. The role of ß-catenin in enrichment of CSC spheroids was confirmed using siRNA interference. Tumorigenic capabilities were confirmed using orthotopic immunocompetent mouse model by injecting 2 × 106 Hepa1-6 CSC spheroids or control cells in upper left liver lobe. RESULTS: The serum-free cultured Hepa1-6 cells demonstrated self-renewal, spheroid formation, higher EpCAM expression, increased Hoechst-33342 efflux, and upregulated Wnt/ß-catenin signaling. Wnt/ß-catenin pathway upregulation was implicated with the downstream targets, i.e., c-MYC, Cyclin-D1, and LEF1. Also, we found that GSK-3ß serine-9 phosphorylation increased in Hepa1-6 spheroids. Silencing ß-catenin by siRNA reversed spheroid formation phenotype. Mice injected with Hepa1-6 CSC spheroids showed aggressive tumor initiation and growth compared with mice injected with control cells. CONCLUSIONS: Successfully induced Hepa1-6 spheroids were identified with CSC-like properties. Aberrant ß-catenin upregulation mediated by GSK-3ß was observed in the Hepa1-6 spheroids. The ß-catenin mediated CSC enrichment in the induced spheroids possesses the capability of tumor initiation in immunocompetent mice. Our study suggests plausible cell dedifferentiation mediated by ß-catenin contributes to CSC-initiated HCC tumor growth in vivo.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Células-Tronco Neoplásicas/metabolismo , beta Catenina/metabolismo , Animais , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Camundongos , Neoplasias Experimentais , Esferoides Celulares , Células Tumorais Cultivadas , Via de Sinalização Wnt/fisiologia
19.
J Surg Res ; 229: 156-163, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29936984

RESUMO

BACKGROUND: Oxidative stress secondary to bile-acid exposure has been associated with metaplastic degeneration of normal esophageal mucosa into Barrett's esophagus (BE) cells and eventually esophageal adenocarcinoma. We previously reported that the macromolecular response of BE cells to this stress was largely regulated by the expression of manganese-dependent mitochondrial superoxide dismutase (MnSOD). As the mitochondrion plays a vital role in MnSOD activation, this study sought to determine the location and activity of MnSOD within BE cells after exposure to oxidative stress. METHODS: A human BE cell line, BAR-T cell, was exposed 0.4 mM concentrations of taurocholic acid (Tau) or a 0.4 mM 1:1 mixture of bile salts for 4 h. Cell viability was performed with 3-(4, 5-dimthyl-thiazol-2-yl)-2, 5-diphenyltetrazolium bromide assays. Proteins were extracted and separated into mitochondrial, nuclear, and cytoplasmic fractions followed by analysis by a western blot and enzymatic activities. RESULTS: BAR-T cell showed resistance to the bile-salt insults. Expression of MnSOD was significantly increased in the cells exposed to a mixture of bile acids and Tau versus control. Mitochondria MnSOD is abundant and highly active. Nuclear fraction displayed presence of both MnSOD and Cu/zinc superoxide dismutase secondary to bile-acid exposure; however, the MnSOD was inactive in nuclear fraction. CONCLUSIONS: This is the first study to specifically evaluate cellular fraction MnSOD expression, increased in BE cells in response to the oxidative stress of bile exposure. Mitochondrial MnSOD contributes to resistance of BAR-T cells to the bile-salt insults. Further investigation is required to determine the potential correlation between bile exposure and BE to adenocarcinoma progression via MnSOD-mediated cell signaling.


Assuntos
Esôfago de Barrett/patologia , Ácidos e Sais Biliares/metabolismo , Mucosa Esofágica/metabolismo , Mitocôndrias/metabolismo , Superóxido Dismutase/metabolismo , Linhagem Celular , Núcleo Celular/metabolismo , Sobrevivência Celular , Citoplasma/metabolismo , Mucosa Esofágica/citologia , Humanos , Estresse Oxidativo , Proteínas Supressoras de Tumor/metabolismo
20.
Org Biomol Chem ; 15(39): 8458-8462, 2017 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-28953279

RESUMO

A novel Cu/Pd cooperatively catalyzed tandem C-N and C-P bond formation reaction between 2-alkynyl azobenzenes and P(O)H compounds has been developed. This reaction provides a convenient approach for the synthesis of various phosphorated 2H-indazoles in moderate to good yields, exhibiting good functional group tolerance and high atom economy.

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