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1.
Small Methods ; : e2400557, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953303

RESUMO

Covalent organic framework (COF) materials, known for their robust porous character, sustainability, and abundance, have great potential as cathodes for aqueous Zn-ion batteries (ZIBs). However, their application is hindered by low reversible capacity and discharge voltage. Herein, a donor-acceptor configuration COF (NT-COF) is utilized as the cathode for ZIBs. The cell exhibits a high discharge voltage plateau of ≈1.4 V and a discharge capacity of 214 mAh g-1 at 0.2 A g-1 when utilizing the Mn2+ electrolyte additive in the ZnSO4 electrolyte. A synergistic combination mechanism is proposed, involving the deposition/dissolution reactions of Zn4SO4(OH)6·4H2O and the co-(de)insertion reactions of H+ and SO4 2- in NT-COF. Meanwhile, the NT-COF with a donor-acceptor configuration facilitates efficient generation and separation of electron-hole pairs upon light exposure, thereby enhancing electrochemical reactions within the battery. This leads to a reduction in charging voltage and internal overvoltage, ultimately minimizing electricity consumption. Under ambient weather conditions, the cell exhibits an average discharge capacity of 430 mAh g-1 on sunny days and maintains consistent cycling stability for a duration of 200 cycles (≈19 days) at 0.2 A g-1. This research inspires the advancement of Zn-organic batteries for high-energy-density aqueous electrochemical energy storage systems or photo-electrochemical batteries.

2.
Biomed Pharmacother ; 175: 116615, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38663101

RESUMO

Estrogens play a critical role in the initiation and progression of breast cancer. Estrogen receptor (ER)α, ERß, and G protein-coupled estrogen receptor are the primary receptors for estrogen in breast cancer. These receptors are mainly activated by binding with estrogens. The crosstalk between ERs and membrane growth factor receptors creates additional pathways that amplify the effects of their ligands and promote tumor growth. This crosstalk may cause endocrine therapy resistance in ERα-positive breast cancer. Furthermore, this may explain the resistance to anti-human epidermal growth factor receptor-2 (HER2) treatment in ERα-/HER2-positive breast cancer and chemotherapy resistance in triple-negative breast cancer. Accordingly, it is necessary to understand the complex crosstalk between ERs and growth factor receptors. In this review, we delineate the crosstalk between ERs and membrane growth factor receptors in breast cancer. Moreover, this review highlights the current progress in clinical treatment and discusses how pharmaceuticals target the crosstalk. Lastly, we discuss the current challenges and propose potential solutions regarding the implications of targeting crosstalk via pharmacological inhibition. Overall, the present review provides a landscape of the crosstalk between ERs and membrane growth factor receptors in breast cancer, along with valuable insights for future studies and clinical treatments using a chemotherapy-sparing regimen to improve patient quality of life.


Assuntos
Neoplasias da Mama , Receptores de Estrogênio , Humanos , Receptores de Estrogênio/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Feminino , Animais , Receptor Cross-Talk/efeitos dos fármacos , Receptores de Fatores de Crescimento/metabolismo , Receptores de Fatores de Crescimento/antagonistas & inibidores , Terapia de Alvo Molecular , Transdução de Sinais/efeitos dos fármacos , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia
3.
Neuromolecular Med ; 26(1): 17, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38684592

RESUMO

Post-stroke neuroinflammation affects the damage and recovery of neurological functions. T cells including CD8+ T cells were present in the ipsilateral hemisphere in the subacute and late phases of ischemic stroke. However, the potential roles of CD8+ T cell subsets in the progression of neuroinflammation have not been characterized. In the current mouse transient middle cerebral artery occlusion model, we investigated the existence of CD8+ T cell subsets in the ipsilateral hemisphere in the subacute and late phases of stroke. We found that ipsilateral CD8+ T cells were present on post-stroke day 3 and increased on post-stroke day 30. The day-3 ipsilateral CD8+ T cells predominantly produced interferon-γ (IFN-γ), while the day-30 ipsilateral CD8+ T cells co-expressed IFN-γ and interleukin-17A (IL-17A). In addition, evaluation of cytokines and transcription factors of the day-30 ipsilateral CD8+ T cells revealed the presence of T cytotoxic 1 (Tc1), T cytotoxic 17 (Tc17), and T cytotoxic 17/1 (Tc17/1) cells. Furthermore, based on the expression of a series of chemokine/cytokine receptors, viable ipsilateral Tc1, Tc17, and Tc17.1 cells were identified and enriched from the day-30 ipsilateral CD8+ T cells, respectively. Co-culture of microglia with ipsilateral Tc1, Tc17, or Tc17.1 cells indicated that the three CD8+ T cell subsets up-regulated the expression of pro-inflammatory mediators by microglia, with Tc17.1 cells being the most potent cell in doing so. Collectively, this study sheds light on the contributions of Tc1, Tc17, and Tc17.1 cells to long-term neuroinflammation after ischemic stroke.


Assuntos
Infarto da Artéria Cerebral Média , Interleucina-17 , Camundongos Endogâmicos C57BL , Microglia , Doenças Neuroinflamatórias , Linfócitos T Citotóxicos , Animais , Microglia/metabolismo , Camundongos , Masculino , Infarto da Artéria Cerebral Média/imunologia , Infarto da Artéria Cerebral Média/patologia , Linfócitos T Citotóxicos/imunologia , Doenças Neuroinflamatórias/etiologia , AVC Isquêmico/imunologia , Interferon gama/biossíntese , Encéfalo , Células Th17/imunologia , Modelos Animais de Doenças , Linfócitos T CD8-Positivos , Técnicas de Cocultura , Células Cultivadas
4.
Front Cell Dev Biol ; 12: 1338448, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38476263

RESUMO

Triple-negative breast cancer (TNBC) is a biologically and clinically heterogeneous disease. The G protein-coupled estrogen receptor (GPER) plays a crucial role in mediating the effect of estrogen and estrogen-like compounds in TNBC cells. Compared with other subtypes, GPER has a higher expression in TNBC. The GPER mechanisms have been thoroughly characterized and analyzed in estrogen receptor α (ERα) positive breast cancer, but not in TNBC. Our previous work revealed that a higher expression of GPER mRNA indicates a better prognosis for ERα-positive breast cancer; however, its effects in TNBC differ. Whether GPER could serve as a predictive prognostic marker or therapeutic target for TNBC remains unclear. In this review, we provide a detailed introduction to the subcellular localization of GPER, the different effects of various ligands, and the interactions between GPER and closely associated factors in TNBC. We focused on the internal molecular mechanisms specific to TNBC and thoroughly explored the role of GPER in promoting tumor development. We also discussed the interaction of GPER with specific cytokines and chemokines, and the relationship between GPER and immune evasion. Additionally, we discussed the feasibility of using GPER as a therapeutic target in the context of existing studies. This comprehensive review highlights the effects of GPER on TNBC, providing a framework and directions for future research.

5.
Angew Chem Int Ed Engl ; 63(13): e202318763, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38300154

RESUMO

The synthesis of mono-N-methylated aliphatic primary amines has traditionally been challenging, requiring noble metal catalysts and high-pressure H2 for achieving satisfactory yields and selectivity. Herein, we developed an approach for the selective coupling of methanol and aliphatic primary amines, without high-pressure hydrogen, using a manganese-based catalyst. Remarkably, up to 98 % yields with broad substrate scope were achieved at low catalyst loadings. Notably, due to the weak base-catalyzed alcoholysis of formamide intermediates, our novel protocol not only obviates the addition of high-pressure H2 but also prevents side secondary N-methylation, supported by control experiments and density functional theory calculations.

6.
Biomedicines ; 12(1)2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38255177

RESUMO

Reactive oxygen species (ROS) has great influence in many physiological or pathological processes in organisms. In the site of bone defects, the overproduced ROS significantly affects the dynamic balance process of bone regeneration. Many antioxidative organic and inorganic antioxidants showed good osteogenic ability, which has been widely used for bone repair. It is of great significance to summarize the antioxidative bone repair materials (ABRMs) to provide guidance for the future design and preparation of osteogenic materials with antioxidative function. Here, this review introduced the major research direction of ABRM at present in nanoscale, 2-dimensional coating, and 3-dimensional scaffolds. Moreover, the referring main active substances and antioxidative properties were classified, and the positive roles of antioxidative materials for bone repair have also been clearly summarized in signaling pathways, antioxidant enzymes, cellular responses and animal levels.

7.
Cancer Lett ; 533: 215605, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35219772

RESUMO

Although the tumorigenic potential of glioma stem cells (GSCs) is associated with multiple molecular alterations, the gene amplification status of GSCs has not been elucidated. Overexpression of HomeoboxA5 (HOXA5) is associated with increased glioma malignancy. In this study, we identify the gene amplification and protein overexpression of HOXA5 in GSCs and its function in regulating GSC maintenance and the downstream transcriptional effector, to explore the significance of HOXA5 amplification/overexpression for GSC identification and prognostic determination. The HOXA5 gene is significantly amplified in glioblastoma (GBM) and is an independent prognostic factor for predicting worse patient outcomes. Specifically, HOXA5 gene amplification and the resultant protein overexpression are correlated with increased proportions of GSCs and enhanced self-renewal/invasiveness of these cells. Disruption of HOXA5 expression impairs GSC survival and GBM tumor propagation. Mechanistically, HOXA5 directly binds to the promoter region of protein tyrosine phosphatase receptor type Z1 (PTPRZ1), thereby upregulating this gene for GSC maintenance. Suppression of PTPRZ1 largely compromises the pro-tumoral effect of HOXA5 on GSCs. In summary, HOXA5 amplification serves as a genetic biomarker for predicting worse GBM outcome, by enhancing PTPRZ1-mediated GSC survival.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioma , Neoplasias Encefálicas/patologia , Carcinogênese/metabolismo , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Glioblastoma/patologia , Glioma/patologia , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Células-Tronco Neoplásicas/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Proteínas Tirosina Fosfatases Classe 5 Semelhantes a Receptores/metabolismo
8.
Nanoscale ; 13(38): 16349-16361, 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34581718

RESUMO

Ceria (CeO2) based materials possess many antioxidant enzyme-like activities and unique properties for bone repair, but their free radical scavenging function is still insufficient. In order to deal with the complex oxidative stress environment in bone repair, multifunctional composite CeO2 nanozymes (CeO2NZs), featuring multiple antioxidative properties, were constructed via surface modification on CeO2NZs with nanoscale poly(tannic acid) (PTA) coatings. Moreover, we adjusted pH conditions (ranging from 4 to 9) to effectively control the formation and antioxidative properties of PTA coatings on CeO2NZ surfaces. Here, the physical properties of this novel inorganic and organic composite antioxidant, such as surface morphology, particle size, crystal structure, surface charge and element composition, were thoroughly characterized. The PTA/CeO2NZs showed obvious coating morphology under weak acid conditions (pH = 5-6), and the PTA layer at pH = 5 is about 1 nm in thickness. Compared with untreated CeO2NZs, the PTA/CeO2NZs showed stronger SOD-like activity and obviously higher free radical scavenging rate (for both ABTS+˙ and DPPH˙).Notably, this composite antioxidative nanozyme not only exhibited favorable cell proliferation of preosteoblasts (MC3T3-E1) but also provided strong antioxidative property to maintain cell vitality against H2O2 induced oxidative damage. In particular, this study provides new insights into the designing of surface polyphenolic coatings at the nanoscale, and these multiple antioxidative properties shown by PTA coated CeO2NZs make them suitable for protecting cells under the oxidative stress environment.


Assuntos
Antioxidantes , Taninos , Proliferação de Células , Peróxido de Hidrogênio , Estresse Oxidativo
9.
Mol Med Rep ; 16(4): 4627-4633, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28791368

RESUMO

Pasteurella multocida is an important pathogen that leads to a range of diseases that have severe economic consequences on cattle production. In order to develop an effective cross­protective component vaccine, an immunoproteomics approach was used to analyze outer membrane proteins (OMPs) of the P. multocida serotype A, B and F strains. Candidate antigen molecules from the whole genome were screened via linear trap quadrupole mass spectrometry and bioinformatics analysis, and the reactogenicity of the candidate antigen molecules was analyzed via cloning, expression, and ELISA or protein immunoblotting, and the vaccine efficacy of the candidate molecules was determined in infective animal models and cross­protective antigens may be obtained. rPmCQ2_2g0128, rPmCQ2_1g0327 and rPmCQ2_1g0020 proteins were selected. Their protective rates were 40/30/20% (rPmCQ2_2g0128), 50/40/0% (rPmCQ2_1g0327) and 0/40/30% (rPmCQ2_1g0020) against ten­fold median lethal dose (10LD50) of the P. multocida serotypes A, B and F in a mouse model, respectively. The results suggested that the two proteins rPmCQ2_2g0128 and rPmCQ2_1g0327 may be used as vaccine candidates against bovine P. multocida serotypes A, B. To the best of our knowledge, the present study was the first to identify cross­protective antigens, extracted OMPs from bovine P. multocida.


Assuntos
Antígenos de Bactérias/imunologia , Reações Cruzadas/imunologia , Infecções por Pasteurella/veterinária , Pasteurella multocida/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/química , Proteínas da Membrana Bacteriana Externa/química , Proteínas da Membrana Bacteriana Externa/imunologia , Bovinos , Doenças dos Bovinos/imunologia , Doenças dos Bovinos/microbiologia , Biologia Computacional/métodos , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Camundongos
10.
Huan Jing Ke Xue ; 37(6): 2171-2178, 2016 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-29964883

RESUMO

To reveal the controlling mechanism of urban polluted river,four trophic level urban river was studied. The change of distribution of organic matter and nitrogen in the sediment was studied while the organic matter was disposed. High level of organic matter is the significant feature of urban city rivers. the humin (HM) was the major fraction of humus, accounting for more than 65% of OM. The most proportion of the total nitrogen (TN) was organic nitrogen which accounted for more than 50%. The amount of organic matter removal increased after the sediment adsorbed the saturated ammonia, which suggested ammonia as the main limited factor for the decomposition of organic matter. The most of Ammonia was adsorbed onto unstable humins. The HM was more stable than other organic matter which was disposed by Hydrogen peroxide (H2O2).


Assuntos
Carbono/química , Sedimentos Geológicos/química , Substâncias Húmicas/análise , Nitrogênio/química , Rios/química , Poluentes Químicos da Água/análise , China , Cidades , Monitoramento Ambiental , Peróxido de Hidrogênio
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