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1.
Toxicol Appl Pharmacol ; 483: 116835, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38272317

RESUMO

Actin-interacting proteins are important molecules for filament assembly and cytoskeletal signaling within vascular endothelium. Disruption in their interactions causes endothelial pathogenesis through redox imbalance. Actin filament redox regulation remains largely unexplored, in the context of pharmacological treatment. This work focused on the peptidyl methionine (M) redox regulation of actin-interacting proteins, aiming at elucidating its role on governing antioxidative signaling and response. Endothelial EA.hy926 cells were subjected to treatment with salvianolic acid B (Sal B) and tert-butyl-hydroperoxide (tBHP) stimulation. Mass spectrometry was employed to characterize redox status of proteins, including actin, myosin-9, kelch-like erythroid-derived cap-n-collar homology-associated protein 1 (Keap1), plastin-3, prelamin-A/C and vimentin. The protein redox landscape revealed distinct stoichiometric ratios or reaction site transitions mediated by M sulfoxide reductase and reactive oxygen species. In comparison with effects of tBHP stimulation, Sal B treatment prevented oxidation at actin M325, myosin-9 M1489/1565, Keap1 M120, plastin-3 M592, prelamin-A/C M187/371/540 and vimentin M344. For Keap1, reaction site was transitioned within its scaffolding region to the actin ring. These protein M oxidation regulations contributed to the Sal B cytoprotective effects on actin filament. Additionally, regarding the Keap1 homo-dimerization region, Sal B preventive roles against M120 oxidation acted as a primary signal driver to activate nuclear factor erythroid 2-related factor 2 (Nrf2). Transcriptional splicing of non-POU domain-containing octamer-binding protein was validated during the Sal B-mediated overexpression of NAD(P)H dehydrogenase [quinone] 1. This molecular redox regulation of actin-interacting proteins provided valuable insights into the phenolic structures of Sal B analogs, showing potential antioxidative effects on vascular endothelium.


Assuntos
Actinas , Antioxidantes , Benzofuranos , Depsídeos , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Actinas/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Vimentina/metabolismo , Estresse Oxidativo , Metionina , Fator 2 Relacionado a NF-E2/metabolismo , Oxirredução , Proteínas do Citoesqueleto/metabolismo , Miosinas/metabolismo , Miosinas/farmacologia
2.
Toxicol Appl Pharmacol ; 472: 116571, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37269934

RESUMO

Bacterial lipopolysaccharide (LPS) is a toxic stimulant to macrophage inflammation. Inflammation intersects cell metabolism and often directs host immunopathogenesis stress. We aim here at pharmacological discovering of formononetin (FMN) action, to which anti-inflammatory signaling spans across immune membrane receptors and second messenger metabolites. In ANA-1 macrophage stimulated by LPS, and simultaneous treatment with FMN, results show the Toll-like receptor 4 (TLR4) and estrogen receptor (ER) signals, in concert with reactive oxygen species (ROS) and cyclic adenosine monophosphate (cAMP), respectively. LPS stimulates inactivation of the ROS-dependent nuclear factor erythroid 2-related factor 2 (Nrf2) by upregulating TLR4, but it does not affect cAMP. However, FMN treatment not only activates Nrf2 signaling by TLR4 inhibition, but also it activates cAMP-dependent protein kinase activities by upregulating ER. The cAMP activity gives rise to phosphorylation (p-) of protein kinase A, liver kinase B1 and 5'-AMP activated protein kinase (AMPK). Moreover, bidirectional signal crosstalk is amplified between p-AMPK and ROS, as FMN combinational validation with AMPK activator/inhibitor/target small-interfering RNA or ROS scavenger. The signal crosstalk is well positioned serving as the 'plug-in' knot for rather long signaling axis, and the immune-to-metabolic circuit via ER/TLR4 signal transduction. Collectively, convergence of the FMN-activated signals drives significant reduction of cyclooxygenase-2, interleukin-6 and NLR family pyrin domain-containing protein 3, in LPS-stimulated cell. Although anti-inflammatory signaling is specifically related to the immune-type macrophage, the p-AMPK antagonizing effect arises from FMN combination with ROS scavenger H-bond donors. Information of our work assists in predictive traits against macrophage inflammatory challenges, using phytoestrogen discoveries.


Assuntos
Proteínas Quinases Ativadas por AMP , Receptor 4 Toll-Like , Humanos , Espécies Reativas de Oxigênio/metabolismo , Receptor 4 Toll-Like/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Lipopolissacarídeos/toxicidade , Fator 2 Relacionado a NF-E2/metabolismo , Transdução de Sinais , Macrófagos , Inflamação/induzido quimicamente , Inflamação/metabolismo , Anti-Inflamatórios/farmacologia
3.
Reprod Biol Endocrinol ; 21(1): 57, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37340405

RESUMO

BACKGROUND: Unexplained recurrent spontaneous abortion (URSA) is one of the most challenging conditions frustrates women of childbearing age profoundly. The gene expression patterns and biological characteristics of placental villus in patients with URSA remain largely unknown. The aim of our study was to identify potential lncRNAs as well as their action mechanisms in URSA. METHOD: The ceRNA microarray was used to identify the mRNA and lncRNA expression profiles of URSA patients and normal pregnancy. Functional enrichment analyses for differentially expressed mRNAs in URSA were performed. Protein-protein interaction analysis of differentially expressed mRNAs was performed to identify hub genes and key modules. Subsequently, the co-dysregulated ceRNA network of URSA was established, and the enrichment analyses for the mRNAs in the ceRNA network was implemented. qRT-PCR was performed to validated the expression of key ENST00000429019 and mRNAs in URSA. RESULTS: We found that URSA placental villus have distinct mRNA and lncRNA expression profiles through ceRNA microarray, with a total of 347 mRNAs and 361 lncRNAs differentially expressed compared with controls. The functional enrichment analysis revealed that ncRNA processing, DNA replication, cell cycle, apoptosis, cytokine-mediated signaling pathway, ECM-receptor interaction were the potentially disrupted pathways in URSA patients. Then we constructed a co-dysregulated ceRNA network and found differentially expressed mRNAs were regulated by a small fraction of hub lncRNAs. Finally, we found a key network of ENST00000429019 and three cell proliferation or apoptosis related key mRNAs (CDCA3, KIFC1, NCAPH), and validated their expression and regulation in tissue and cellular levels. CONCLUSIONS: This study identified a key ceRNA network, which might take part in URSA and correlate with cell proliferation and apoptosis. Optimistically, this study may deepen our apprehensions about the underlying molecular and biological causes of URSA and provide an important theoretical basis for future therapeutic strategies for patients with URSA.


Assuntos
Aborto Habitual , MicroRNAs , RNA Longo não Codificante , Humanos , Feminino , Gravidez , MicroRNAs/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Vilosidades Coriônicas/metabolismo , Redes Reguladoras de Genes , Placenta/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Aborto Habitual/genética , Proteínas Nucleares/genética , Proteínas de Ciclo Celular/genética
4.
Inorg Chem ; 62(21): 8210-8218, 2023 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-37194614

RESUMO

Photodynamic therapy (PDT) uses a combination of photosensitizers (PSs), light sources, and reactive oxygen species (ROS) to damage only the desired target and keep normal tissues from being hurt. The dark cytotoxicity (chemotoxicity) of PSs, leading to whole-body damage in the absence of irradiation, is a major limiting factor in PDT. How to simultaneously increase ROS generation and decrease dark cytotoxicity is an essential challenge that must be resolved in PS research. In this study, a series of homoligand polypyridyl ruthenium complexes (HPRCs) containing three singlet oxygen (1O2)-generating ligands (L) in a single molecule ([Ru(L)3]2+) have been constructed. Compared to the heteroligand complexes [Ru(bpy)2(L)]2+ where bpy is 2,2'-bipyridine, the 1O2 quantum yield under infrared two-photon irradiation and the DNA photocleavage effect of the HPRCs are significantly enhanced with two more ligands L. The intraligand triplet excited states transition played an important role in the activation of oxygen. The HPRCs target the mitochondria but not the nuclei, generating 1O2 intracellularly under irradiation of visible or infrared light. Ru1 exhibits high phototoxicity and low dark cytotoxicity toward human malignant melanoma cells in vitro. Moreover, HPRCs have minimal cytotoxicity to human normal liver cells, suggesting their potential as antitumor PDT reagents with more security. This study may provide inspiration for the structural design of potent PS for PDT.


Assuntos
Complexos de Coordenação , Fotoquimioterapia , Rutênio , Humanos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/química , Rutênio/farmacologia , Rutênio/química , Espécies Reativas de Oxigênio , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química
5.
Phys Chem Chem Phys ; 25(6): 5029-5036, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36722879

RESUMO

Recently, layered BeN4 as a novel Dirac semimetal has been fabricated (M. Bykov, T. Fedotenko, S. Chariton et al. Phys. Rev. Lett., 2021, 126, 175501). Motivated by the experiment, we perform first-principles calculations to predict the stability, magnetic configurations, and electronic structures of unsaturated BeN4 nanoribbons with an armchair-terminated edge. The magnetic interactions and electronic properties of BeN4 nanoribbons are sensitively influenced by the edge morphology. The BeN4 nanoribbons with both edges occupied by Be atoms undergo a transition from a ferromagnetic (FM) metal to an antiferromagnetic (AFM) semiconductor with the increase of ribbon width. The configurations with edges situated by Be and N atoms are FM/ferrimagnetic (FIM) metals or nearly half-metals, and the spin polarizability is as high as 85% when the ribbon width is N = 5. The nanoribbons with both edge sites occupied by pentagonal N atoms are nonmagnetic (NM), while the nanoribbons terminated by N atoms in a hexagonal ring are FM metals. We also explore the magnetic properties and band structures of BeN4 nanoribbons with hydrogen passivation. Our results open up a versatile edge engineering avenue to design BeN4-based spintronic and nanoelectronic devices.

6.
Pol J Pathol ; 74(3): 182-193, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37955537

RESUMO

S100 calcium-binding protein A16 (S100A16) has previously been reported to play a role in tumor cells. Nevertheless, the role that S100A16 played in nephroblastoma cells remains obscure. The expression of S100A16 and DEPDC1 were detected via RT-q PCR and western blotting. Cell transfection was performed to overexpress DEPDC1 or interfere S100A16. CCK8 was applied for the assessment of cell viability. The apoptotic level and the capabilities of WiT49 cells to proliferate, invade and migrated were appraised utilizing Tunel, colony formation Transwell, and wound healing, separately. The angiogenesis was estimated through tube formation assay. Co-immunoprecipitation (CO-IP) was performed to examine the targeted binding of S100A16 to DEPDC1. The contents of PI3K/Akt/mTOR pathway-related proteins were resolved by virtue of western blot. S100A16 and DEPDC1 expression levels were significantly increased in nephroblastoma cell lines. S100A16 deletion suppressed nephroblastoma cell proliferative, invasive, migrative and angiogenetic capabilities but facilitated the apoptotic level. Moreover, S100A16 could bind DEPDC1, DEPDC1 overexpression partially reversed the inhibitory effect of S100A16 interference on nephroblastoma cell. DEPDC1 overexpression also partially counteracted the suppressive impacts of S100A16 interference on PI3K/Akt/mTOR pathway-related proteins. S100A16 synergistic with DEPDC1 promotes the progression and angiogenesis of nephroblastoma cell through the PI3K/Akt/mTOR pathway.


Assuntos
Proteínas Proto-Oncogênicas c-akt , Tumor de Wilms , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Linhagem Celular Tumoral , Serina-Treonina Quinases TOR/metabolismo , Tumor de Wilms/genética , Proteínas de Neoplasias/metabolismo , Proteínas Ativadoras de GTPase/metabolismo , Proteínas S100/metabolismo
7.
Angew Chem Int Ed Engl ; 62(37): e202308029, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37469108

RESUMO

Chiral induction by natural biomolecules can reveal the indispensable role of chiral structures in life and can be used to develop the chirality-sensing biomolecular recognition. Here, we present the synthesis and characterization of an achiral supramolecular organic framework (SOF-1) constructed from cucurbit[8]uril (CB[8]) and hexaphenylbenzene (HPB) derivative (1) in water. Due to the propeller-like rotational chiral conformation of HPB units and the specific recognition properties of CB[8], SOF-1 demonstrates chiral adaptive induction in water when interacting with the N-terminal Trp-/Phe-containing dipeptides including L-TrpX and L-PheX (X is an amino acid residue), respectively, exhibiting contrasting circular dichroism (CD) and circularly polarized luminescence (CPL) spectra. Consequently, SOF-1 has been developed as a supramolecular host and chiroptical sensor capable of recognizing and distinguishing the sequence-opposite Trp-/Phe-containing dipeptide pairs including L-TrpX/L-XTrp and L-PheX/L-XPhe based on the sequence-selective CD responses.

8.
Phys Chem Chem Phys ; 24(44): 27474-27482, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36342047

RESUMO

In recent accomplishments, a new two-dimensional allotrope of carbon-biphenylene (BP) was experimentally synthesized [Fan et al., Science, 372, 852-856 (2021)]. The BP sheet is composed of four-, six-, and eight-membered carbon rings constructed using periodically arranged sp2-hybridized carbon atoms. Unlike semi-metallic graphene, BP is metallic with quite active atoms and chemical bonds, and the binding strength with reaction intermediates will be enhanced, which means that it may exhibit good catalytic activity in some electrochemical catalytic reactions. Using spin-polarized density functional theory based on first-principles simulations and ab initio molecular dynamic calculations, we systematically investigated the structure, thermodynamic stability, CO2 reduction reaction (CO2RR) activity and product selectivity of a precise number of Fen (n = 1-3) atoms embedded on a BP monolayer. The calculated results indicate that our designed Fe1@BP, Fe2@BP and Fe3@BP complexes possess good thermodynamic and electrochemical stabilities and strong absorption for CO2, which promotes the activation of CO2. Furthermore, the Fe2@BP catalyst possesses good catalytic ability for the CO2RR to CH3OH due to a small rate determining potential of -0.48 V. In addition, Fe2- and Fe3@BP catalysts demonstrate superior catalytic performance for the CO2RR to CH4 with low rate-limiting steps. More importantly, both the Fe2 and Fe3@BP catalysts can effectively suppress the hydrogen evolution reaction (HER) during the entire CO2RR process. The electronic structure analysis shows that the enhanced ability of Fe1-3@BP catalysts for effective CO2 reduction can be attributed to the establishment of strong hybridization between Fe-3d and O-2p or C-2p states, which is conducive to the transfer of strong electrons to the anti-bond orbital of CO2. This work provides an in-depth insight into the intrinsic catalytic mechanisms of the CO2RR on Fe1-3@BP catalysts, and highlights the excellent performance of the BP sheet as a substrate material for the polyatomic catalyst.

9.
Phys Chem Chem Phys ; 24(42): 26307-26315, 2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36282042

RESUMO

Combining various two-dimensional crystals has emerged as an exciting way to tailor the properties of lateral heterostructures for new-generation optoelectronic devices. Herein, a seamless lateral heterostructure based on MoSi2N4 and MoSi2N4 monolayers along armchair interfaces is predicted, and its electronic and optical properties are investigated by using first principles calculations. Our calculations indicate that the MoSi2N4/WSi2N4 lateral heterostructures (HSs) possess excellent stability due to the very small lattice mismatch. In contrast to their parent monolayers with wide indirect band gaps, all (MoSi2N4)m(WSi2N4)n lateral HSs are direct gap semiconductors, and their direct gap nature is independent of compositions and strains. The band alignment of (MoSi2N4)m(WSi2N4)16-m lateral HSs undergoes a quasi-type-I to type-II to quasi-type-II to quasi-type-I band transition with an increase in m. (MoSi2N4)8(WSi2N4)8 is a type-II semiconductor, and the band arrangement changes from type-II to quasi-type-I upon applying tensile strain. Compared with pristine materials, the band edges of MoSi2N4/WSi2N4 lateral HSs are more favorable for photocatalytic water splitting. Furthermore, MoSi2N4/WSi2N4 lateral HSs exhibit higher visible light absorption. These results greatly expand the optoelectronic applications of Mxenes in the 2D realm.

10.
Mol Cancer ; 20(1): 62, 2021 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-33814009

RESUMO

BACKGROUND: Drug-resistance and severe side effects of chemotherapeutic agents result in unsatisfied survival of patients with lung cancer. CXCLs/CXCR2 axis plays an important role in progression of cancer including lung cancer. However, the specific anti-cancer mechanism of targeting CXCR2 remains unclear. METHODS: Immunohistochemical analysis of CXCR2 was performed on the microarray of tumor tissues of clinical lung adenocarcinoma and lung squamous cell carcinoma patients. CCK8 test, TUNEL immunofluorescence staining, PI-Annexin V staining, ß-galactosidase staining, and Western blot were used to verify the role of CXCR2 in vitro. Animal models of tail vein and subcutaneous injection were applied to investigate the therapeutic role of targeting CXCR2. Flow cytometry, qRT-PCR, enzyme-linked immunosorbent assay (ELISA), and immunohistochemistry analysis were performed for further mechanistic investigation. RESULTS: The expression of CXCR2 was elevated in both human lung cancer stroma and tumor cells, which was associated with patients' prognosis. Inhibition of CXCR2 promoted apoptosis, senescence, epithelial-to-mesenchymal transition (EMT), and anti-proliferation of lung cancer cells. In vivo study showed that tumor-associated neutrophils (TANs) were significantly infiltrate into tumor tissues of mouse model, with up-regulated CXCLs/CXCR2 signaling and suppressive molecules, including Arg-1 and TGF-ß. SB225002, a selective inhibitor of CXCR2 showed promising therapeutic effect, and significantly reduced infiltration of neutrophils and enhanced anti-tumor T cell activity via promoting CD8+ T cell activation. Meanwhile, blockade of CXCR2 could enhance therapeutic effect of cisplatin via regulation of neutrophils infiltration. CONCLUSIONS: Our finds verify the therapeutic effects of targeting CXCR2 in lung cancer and uncover the potential mechanism for the increased sensitivity to chemotherapeutic agents by antagonists of CXCR2.


Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , Neoplasias Pulmonares/metabolismo , Receptores de Interleucina-8B/antagonistas & inibidores , Adulto , Idoso , Animais , Apoptose , Biomarcadores , Linhagem Celular Tumoral , Proliferação de Células , Cisplatino/uso terapêutico , Modelos Animais de Doenças , Sinergismo Farmacológico , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transição Epitelial-Mesenquimal/genética , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/patologia , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Estadiamento de Neoplasias , Infiltração de Neutrófilos , Prognóstico , Receptores de Interleucina-8B/genética , Receptores de Interleucina-8B/metabolismo , Microambiente Tumoral/efeitos dos fármacos
11.
Nanotechnology ; 32(21): 215402, 2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33661759

RESUMO

Holey graphyne (HGY), a novel two-dimensional (2D) single-crystalline carbon allotrope, was recently synthesized by Castro-Stephens coupling reaction. The naturally existing uniform periodic holes in the 2D carbon-carbon network demonstrate its promising potential in energy storage. Herein, we conduct density functional theory (DFT) calculation and ab initio molecular dynamics simulations (AIMD) to predict the H storage properties of a single-layer HGY sheet modified by Li metal atoms. The DFT calculations demonstrate that Li atoms can bind strongly to the HGY sheet without forming clusters, and each Li atom can anchor four H2 molecules with an average adsorption energy of about -0.22 eV/H2. The largest H storage capacity of the doped HGY sheet can reach as high as 12.8 wt%, showing that the Li/HGY complex is an ideal H storage material at ambient conditions. In addition, we investigate the polarization mechanism of the storage media and find that the polarization originates from the electric field induced by both the ionic Li atoms and the weak polarized H2 molecules. Finally, the desorption mechanism of the adsorbed H2 molecules is thoroughly investigated using a kinetic AIMD method.

12.
Nanotechnology ; 2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33561848

RESUMO

Holey graphyne (HGY), a novel two-dementional 2D single-crystalline carbon allotrope, was recently synthesized by Castro-Stephens coupling reaction. The naturally existing uniform periodic holes in the 2D carbon-carbon network demonstrate its promising potential in the energy storage. Herein, we conducted density functional theory (DFT) calculation to predict the hydrogen storage capacity of HGY sheet. It is found the Li-decorated single-layer HGY can serve as a promising candidate for hydrogen storage. Our DFT calculations demonstrate that Li atoms can bind strongly to the HGY sheet without the formation of Li clusters, and each Li atom can anchor four H2 molecules with the average adsorption energy about 0.22 eV/H2. The largest hydrogen storage capacity of the doped HGY sheet can reach as high as 12.8 wt%, largely surpassing the target of the U. S. DOE (9 wt%), showing the Li/HGY complex is an ideal hydrogen storage material at ambient conditions. In addition, we investigate the polarization mechanism of the storage media and find that the polarization is originated from both the electric field induced by the ionic Li decorated on the HGY and the weak polarized hydrogen molecules dominated the H2 adsorption process.

13.
Angew Chem Int Ed Engl ; 60(12): 6744-6751, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33289262

RESUMO

Chiral framework materials have been developed for many applications including chiral recognition, chiral separation, asymmetric catalysis, and chiroptical materials. Herein, we report that an achiral cucurbit[8]uril-based supramolecular organic framework (SOF-1) with the dynamic rotational conformation of tetraphenylethene units can exhibit adaptive chirality to produce M-SOF-1 or P-SOF-1 with mirror-image circular dichroism (CD) with gabs ≈±10-4 and circularly polarized luminescence (CPL) with glum ≈±10-4 induced by L-/D-phenylalanine in water, respectively. The chirality induction in CD (gabs ≈-10-4 ) and CPL (glum ≈-10-4 ) of P-SOF-1 from achiral SOF-1 can be presented by using a small amount of adenosine-5'-triphosphate disodium (ATP) or adenosine-5'-diphosphate disodium (ADP) (only 0.4 equiv) in water. Furthermore, the adaptive chirality of SOF-1 can be used to determine dipeptide sequences (e.g., Phe-Ala and Ala-Phe) and distinguish polypeptides/proteins (e.g., somatostatin and human insulin) with characteristic CD spectra. Therefore, achiral SOF-1 as an ideal chiroptical platform with adaptive chirality may be applied to determine the enantiopurity of amino acids (e.g., L-/D-phenylalanine), develop aqueous CPL materials, and distinguish biological chiral macromolecules (e.g., peptides/proteins) via chirality induction in water.

14.
Angew Chem Int Ed Engl ; 59(25): 10101-10110, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-31692185

RESUMO

We report the synthesis and characterization of a three-dimensional tetraphenylethene-based octacationic cage that shows host-guest recognition of polycyclic aromatic hydrocarbons (e.g. coronene) in organic media and water-soluble dyes (e.g. sulforhodamine 101) in aqueous media through CH⋅⋅⋅π, π-π, and/or electrostatic interactions. The cage⊃coronene exhibits a cuboid internal cavity with a size of approximately 17.2×11.0×6.96 Å3 and a "hamburger"-type host-guest complex, which is hierarchically stacked into 1D nanotubes and a 3D supramolecular framework. The free cage possesses a similar cavity in the crystalline state. Furthermore, a host-guest complex formed between the octacationic cage and sulforhodamine 101 had a higher absolute quantum yield (ΦF =28.5 %), larger excitation-emission gap (Δλex-em =211 nm), and longer emission lifetime (τ=7.0 ns) as compared to the guest (ΦF =10.5 %; Δλex-em =11 nm; τ=4.9 ns), and purer emission (ΔλFWHM =38 nm) as compared to the host (ΔλFWHM =111 nm).

15.
Metab Brain Dis ; 34(1): 213-221, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30443767

RESUMO

Hepatic encephalopathy (HE) is a serious complication of liver disease. To establish a model for predicting 3-month mortality in patients with HE in China. This retrospective study included 609 patients with HE admitted to the Peoples' Hospital, Liaocheng City, China (August 2006 to January 2016). Patients were allocated to a modeling (n = 409) or validation (n = 200) group. Demographic/clinical characteristics, laboratory test results, Model for End Stage Liver Disease (MELD) score and Child-Turcotte-Pugh (CTP) score were extracted from medical records. A model for predicting death within 3 months after admission was established using logistic regression analysis (modeling group). Model validity (validation group) was assessed using receiver operating characteristic (ROC) curve analysis. 270/409(66.0%) patients died in the modeling group and 142/203(70.0%) died in the validation group. Compared with survivors, patients who died had more severe HE, and higher MELD score, CTP score, incidence of complications including hepatorenal syndrome (HRS) and upper gastrointestinal bleeding, and values for laboratory parameters including red blood cell count(RBC) and total bilirubin(TBIL)(P < 0.05). Regression analysis revealed RBC, TBIL, HE stage, HRS and upper gastrointestinal bleeding as independent factors associated with death (P < 0.05). The area under the ROC curve (AUC) for the model was 0.931.The model had a higher Youden index than MELD or CTP scores and predicted death in the validation group with a sensitivity of 83.1% and specificity of 93.4%. The established model has superior performance to MELD and CTP scores for predicting mortality in patients with HE.


Assuntos
Encefalopatia Hepática/mortalidade , Adulto , Idoso , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos
16.
Pak J Med Sci ; 35(4): 981-986, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31372128

RESUMO

OBJECTIVE: To observe the clinical efficacy of pidotimod in the treatment of recurrent respiratory tract infection in children. METHODS: One hundred thirty-two patients with recurrent respiratory tract infection who received treatment in Tianan City Central Hospital were selected and divided into an observation group and a control group using random number table, 66 in each group. Patients in the control group were given conventional treatment, while patients in the observation group were given conventional treatment and pidotimod treatment; the clinical efficacy of the two therapies was compared. The levels of IgG and IgM were measured after treatment. RESULTS: The vital signs and the content of inflammatory mediator and Th1/Th2 in serum before and after treatment were compared, and the clinical efficacy of the two groups was evaluated. The fever, pulmonary rale, cough and antiadoncus of patients in the observation group disappeared earlier than those in the control group (P<0.05). The onset duration of respiratory tract infection and days of antibiotic application of the observation group were shorter than those of the control group after treatment (P<0.05). The times of infection of the observation group were less than that of the control group (P<0.05). Before treatment, the two groups had no significant difference in the content of inflammatory mediators and Th1/Th2 in the serum (P>0.05). The serum content of tumor necrosis factor (TNF)-α and interleukin (IL)-4 of the two groups one week after treatment was lower than that before treatment, and the content of interferon (IFN)-γ and IFN-γ/IL-4 were higher than that before treatment; moreover the observation group had lower serum content of TFN-α and IL-4 and lower content of IFN-γ and IFN-γ/IL-4 compared to the control group (P<0.05). The overall response rate of the observation group was 92.4%, much higher than 81.8% in the control group (P<0.05). CONCLUSION: Pidotimod has a remarkable efficacy in the treatment of pediatric recurrent respiratory tract infection because it can effectively inhibit the infection and optimize Th1/Th2 immune function.

17.
Phys Chem Chem Phys ; 20(37): 24011-24018, 2018 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-30215647

RESUMO

Based on comprehensive first-principles calculations, we predict that Li-decorated carbon ene-yne (CEY) can serve as a reversible and high density hydrogen storage medium. The adsorption structures, charge transfer, electronic properties and energy storage characteristics of Li-decorated CEY are investigated. It is established that Li can bind strongly to sp and sp2 hybridized CEY without the formation of Li clusters. The strong interaction between Li and CEY is attributed to the sp binding C px/py states which hybridize heavily with the Li 2s/2p states. After Li decoration, CEY undergoes a transition from a semiconductor to a metal. Each Li atom anchors seven H2 molecules with the average adsorption energy falling in a suitable range (-0.2 to -0.4 eV per H2). The adsorption mechanism of H2 molecules has also been discussed. Two Li atom decorated CEY can obtain up to a 9.96 wt% hydrogen storage capacity.

18.
Biochem Biophys Res Commun ; 487(4): 868-874, 2017 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-28461114

RESUMO

miR-17-92 cluster are overexpressed in hematological malignancies including chronic myeloid leukemia (CML). However, their roles and mechanisms that regulate BCR-ABL induced leukemogenesis remain unclear. In this study, we demonstrated that genomic depletion of miR-17-92 inhibited the BCR-ABL induced leukemogenesis by using a mouse model of transplantation of BCR-ABL transduced hematopoietic stem cells. Furthermore, we identified that miR-19b targeted A20 (TNFAIP3). A20 overexpression results in inactivation of NF-κB activity including decrease of phosphorylation of P65 and IκBα, leads to induce apoptosis and inhibit proliferation and cycle in CML CD34 + cells. Thus we proved that miR-17-92 is a critical contributor to CML leukemogenesis via targeting A20 and activation of NF-κB signaling. These findings indicate that miR-17-92 will be important resources for developing novel treatment strategies of CML and better understanding long-term disease control.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , MicroRNAs/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/metabolismo , Animais , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neoplasias Experimentais/genética , Neoplasias Experimentais/metabolismo , RNA Longo não Codificante
19.
Tumour Biol ; 37(10): 13333-13343, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27460081

RESUMO

Liposarcoma(LPS) is the most common type of soft tissue sarcoma accounting for 20 % of all adult sarcomas. However, the molecular pathogenesis of this malignancy is still poorly understood. Here, we showed that GPS2 expression was downregulated in LPS and correlated with the prognosis of this disease. In vitro study showed that knockdown of GPS2 resulted in enhanced proliferation and migration of LPS cell line SW872, without significant influence of cell death. Conclusively, our results suggest that GPS2 may act as a tumor suppressor in LPS and serve as a potential prognosis marker for this disease.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lipossarcoma/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Adipogenia , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose/genética , Biomarcadores , Ciclo Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Feminino , Seguimentos , Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intracelular/genética , Lipossarcoma/genética , Lipossarcoma/mortalidade , Lipossarcoma/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Transdução de Sinais , Proteínas Supressoras de Tumor/genética
20.
Phys Chem Chem Phys ; 18(22): 14927-32, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27188523

RESUMO

Very recently, a new single-element two-dimensional (2D) material borophene was successfully grown on a silver surface under pristine ultrahigh vacuum conditions which attracts tremendous interest. In this paper, the lattice thermal conductivity, phonon lifetimes, thermal expansion and temperature dependent elastic moduli of borophene are systematically studied by using first-principles. Our simulations show that borophene possesses unique thermal properties. Strong phonon-phonon scattering is found in borophene, which results in its unexpectedly low lattice thermal conductivity. Thermal expansion coefficients along both the armchair and zigzag directions of borophene show impressive negative values. More strikingly, the elastic moduli are sizably strengthened as temperature increases, and the negative in-plane Poisson's ratios are found along both the armchair and zigzag directions at around 120 K. The mechanisms of these unique thermal properties are also discussed in this paper.

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