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1.
Chemistry ; : e202403699, 2024 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-39441551

RESUMO

The construction of helical nanotubes based on chiral coordination polymers (CPs) is an intriguing but challenging task, which is important for the development of functional materials that combine macroscopic chirality with tube-related properties. Here, we selected a chiral europium phosphonate system, e.g., Eu(NO3)3/R-,S-pempH2, and carried out a systematic work. By controlling the hydrothermal reaction conditions such as the pH value of the reaction mixture, the molar ratio and concentration of the reactants, we obtained block-like crystals of R/S-1b, rod-like crystals ofR/S-3r, hollow superhelices of R/S-2hh, and solid superhelices of R/S-4sh. In the latter two cases, the chirality has been successfully transferred and amplificated from the molecular level to the macroscopic level. Interestingly, compounds R/S-2hh and R/S-4sh have the same chemical composition of Eu(R/S-pempH)3×2H2O and show identical PXRD patterns, thus can be considered as the same material except for different morphologies. We further investigated their circularly polarized luminescence (CPL) properties and found that the hollow superhelix of R/S-2hh had a larger dissymmetry factor than the solid superhelix of R/S-4sh. This study not only provides the first example of hollow superhelices of chiral CPs, but also offers the possibility of modulating the chiroptical properties of CPs through morphological control.

2.
J Immunother Cancer ; 12(10)2024 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-39448202

RESUMO

BACKGROUND: Limited activation and infiltration of CD8+ T cells are major challenges facing T cell-based immunotherapy for most solid tumors, of which the mechanism is multilayered and not yet fully understood. METHODS: Levels of CD93 expression on monocytes from paired non-tumor, peritumor and tumor tissues of human hepatocellular carcinoma (HCC) were evaluated. The underlying mechanisms mediating effects of CD93+ monocytes on the inhibition and tumor exclusion of CD8+ T cells were studied through both in vitro and in vivo experiments. RESULTS: In this study, we found that monocytes in the peritumoral tissues of HCC significantly increased levels of CD93 expression, and these CD93+ monocytes collocated with CD8+ T cells, whose density was much higher in peritumor than intratumor areas. In vitro experiments showed that glycolytic switch mediated tumor-induced CD93 upregulation in monocytes via the Erk signaling pathway. CD93 on the one hand could enhance PD-L1 expression through the AKT-GSK3ß axis, while on the other hand inducing monocytes to produce versican, a type of matrix component which interacted with hyaluronan and collagens to inhibit CD8+ T cell migration. Consistently, levels of CD93+ monocytes positively correlated with the density of peritumoral CD8+ T cells while negatively correlated with that of intratumoral CD8+ T cells. Targeting CD93 on monocytes not only increased the infiltration and activation of CD8+ T cells but also enhanced tumor sensitivity to anti-PD-1 treatment in mice in vivo. CONCLUSION: This study identified an important mechanism contributing to the activation and limited infiltration of CD8+ T cells in solid tumors, and CD93+ monocytes might represent a plausible immunotherapeutic target for the treatment of HCC.


Assuntos
Linfócitos T CD8-Positivos , Monócitos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Monócitos/imunologia , Monócitos/metabolismo , Humanos , Animais , Camundongos , Receptores de Complemento/metabolismo , Glicoproteínas de Membrana/metabolismo , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/patologia , Linhagem Celular Tumoral , Masculino , Feminino
3.
Chemistry ; : e202402401, 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39400382

RESUMO

Metal-organic frameworks (MOFs) with kagomé lattice are attractive for their unique physical and chemical properties, but little attention has been paid to their catalytic properties. Herein, we report a 2D MOF based on a phosphonato-amino-carboxylate ligand (NaHL), i.e., [Na0.33Co(L)(CH3OH)2](NO3)0.33 (2), which exhibits an unconventional kagomé lattice. The formation of this kagomé lattice is caused by the selective recognition of the NO3- anion by the phenolato group of L2- as evidenced by theoretical calculations. Compound 2 can be utilized for the α-methoxymethylation and aminomethylation of aromatic ketones using methanol as a C1 source. Interestingly, compound 2 can be exfoliated in-situ into nanosheets with one-layer thickness under catalytic reaction conditions, which improves the catalytic efficiency. Based on the results of experiments and theoretical calculations, we proposed possible pathways for the catalytic reaction.

4.
Acc Chem Res ; 57(20): 2973-2984, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39370784

RESUMO

ConspectusPorous metal phosphonate frameworks (PMPFs) as a subclass of metal-organic frameworks (MOFs) have promising applications in the fields of gas adsorption and separation, ion exchange and storage, catalysis, sensing, etc. Compared to the typical carboxylate-based MOFs, PMPFs exhibit higher thermal and water stability due to the strong coordination ability of the phosphonate ligands. Despite their robust frameworks, PMPFs account for less than 0.51% of the porous MOFs reported so far. This is because metal phosphonates are highly susceptible to the formation of dense layered or pillared-layered structures, and they precipitate easily and are difficult to crystallize. There is a tendency to use phosphonate ligands containing multiple phosphonate groups and large organic spacers to prevent the formation of dense structures and generate open frameworks with permanent porosity. Thus, many PMPFs are composed of chains or clusters of inorganic metal phosphonates interconnected by organic spacers. Using this feature, a wide range of metal ions and organic components can be selected, and their physical properties can be modulated. However, limited by the small number of PMPFs, there are still relatively few studies on the physical properties of PMPFs, some of which merely remain in the description of the phenomena and lack in-depth elaboration of the structure-property relationship. In this Account, we review the strategies for constructing PMPFs and their physical properties, primarily based on our own research. The construction strategies are categorized according to the number (n = 1-4) of phosphonate groups in the ligand. The physical properties include proton conduction, electrical conduction, magnetism, and photoluminescence properties. Proton conductivity of PMPFs can be enhanced by increasing the proton carrier concentration and mobility. The former can be achieved by adding acidic groups such as -POH and/or introducing acidic guests in the hydrophilic channels. The latter can be attained by introducing conjugate acid-base pairs or elevating the temperature. Semiconducting PMPFs, on the other hand, can be obtained by constructing highly conjugated networks of coordination bonds or introducing large conjugated organic linkers π-π stacked in the lattice. In the case of magnetic PMPFs, long-range magnetic ordering occurs at very low temperatures due to very weak magnetic exchange couplings propagated via O-P-O and/or O(P) units. However, lanthanide compounds may be interesting candidates for single-molecule magnets because of the strong single-ion magnetic anisotropy arising from the spin-orbit coupling and large magnetic moments of lanthanide ions. The luminescent properties of PMPFs depend on the metal ions and/or organic ligands. Emissive PMPFs containing lanthanides and/or uranyl ions are promising for sensing and photonic applications. We conclude with an outlook on the opportunities and challenges for the future development of this promising field.

5.
Cancer Res ; 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39356626

RESUMO

Emerging evidence suggests that transforming growth factor ß1 (TGFß1) can inhibit angiogenesis, contradicting the coexistence of active angiogenesis and high abundance of TGFß1 in the tumor microenvironment. Here, we investigated how tumors overcome the anti-angiogenic effect of TGFß1. TGFß1 treatment suppressed physiological angiogenesis in chick chorioallantoic membrane and zebrafish models but did not affect angiogenesis in mouse hepatoma xenografts. The suppressive effect of TGFß1 on angiogenesis was recovered in mouse xenografts by a hypoxia-inducible factor 1α (HIF1α) inhibitor. In contrast, a HIF1α stabilizer abrogated angiogenesis in zebrafish, indicating that hypoxia may attenuate the anti-angiogenic role of TGFß1. Under normoxic conditions, TGFß1 inhibited angiogenesis by upregulating anti-angiogenic factor thrombospondin 1 (TSP1) in endothelial cells (ECs) via TGFß type I receptor (TGFßR1)-SMAD2/3 signaling. In a hypoxic microenvironment, HIF1α induced microRNA-145 (miR145) expression; miR145 abolished the inhibitory effect of TGFß1 on angiogenesis by binding and repressing SMAD2/3 expression and subsequently reducing TSP1 levels in ECs. Primary ECs isolated from human hepatocellular carcinoma (HCC) displayed increased miR145 and decreased SMAD3 and TSP1 compared to ECs from adjacent non-tumor livers. The reduced SMAD3 or TSP1 in ECs was associated with increased angiogenesis in HCC tissues. Collectively, this study identified that TGFß1-TGFßR1-SMAD2/3-TSP1 signaling in ECs inhibits angiogenesis. This inhibition can be circumvented by a hypoxia-HIF1α-miR145 axis, elucidating a mechanism by which hypoxia promotes angiogenesis.

6.
Front Plant Sci ; 15: 1378226, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39411653

RESUMO

Many soils face dual challenges of cadmium (Cd) contamination and salinization. However, the response of crops, especially wheat, to combined Cd and salinity stress is not understood. Here, wheat was grown in a hydroponic model for 14 days under single and combined Cd and NaCl stresses. Growth parameters, tissue Cd2+ and Na+ contents, and leaf chlorophyll (Chl), O2•-, and MDA levels were determined. Comparative transcriptomic and metabolomic analyses of the leaves were performed. The results showed that combined stress had a greater inhibitory effect on Chl contents and generated more O2•- and MDA, resulting in more severe wheat growth retardation than those under Cd or NaCl stress. Stress-induced decrease in Chl levels may be attributed to the inhibition of Chl biosynthesis, activation of Chl degradation, or a decline in glutamate content. Cd addition weakened the promotional effect of NaCl on SOS1 gene expression, thereby increasing the Na+ content. Contrastingly, NaCl supplementation downregulated the Nramp and ZIP gene expressions related to Cd uptake and transport, thereby impeding Cd2+ accumulation. All stresses enhanced tryptophan content via promoting tryptophan biosynthesis. Meanwhile, Cd and NaCl stresses activated phenylpropanoid biosynthesis and purine metabolism, respectively, thereby increasing the levels of caffeic acid, fumaric acid, and uric acid. Activating the TCA cycle was important in the wheat's response to combined stress. Additionally, NaCl and combined stresses affected starch and sucrose metabolism, resulting in sucrose and trehalose accumulation. Our findings provide a comprehensive understanding of the response of wheat to the combined Cd and salinity stress.

7.
JACS Au ; 4(9): 3606-3618, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39328746

RESUMO

The structural, photophysical, and photochemical properties of Ln(depma)(hmpa)2(NO3)3 (Ln = La, Ce, Nd, Sm, Eu, Tb, Ho, Er, and Yb) complexes 1-Ln were investigated with a multidisciplinary approach involving synthesis, photocycloaddition-based crystal engineering, spectroscopic analytical techniques and quantum chemical ab initio calculations. Depending on the Ln3+ ion the isostructural 1-Ln complexes exhibit quite different behavior upon excitation at 350-400 nm. Some 1-Ln complexes (Ln = La, Ce, Sm, Tb, Yb) emit a broad and strong band near 533 nm arising from paired anthracene moieties, whereas others (Ln = Nd, Eu, Ho, Er) do not. 1-Eu is not emissive at all, whereas 1-Nd, 1-Ho, and 1-Er exhibit a Ln3+ based luminescence. Upon irradiation with 365 nm ultraviolet (UV) light 1-Ln (Ln = La, Ce, Sm, Tb, Yb) dimerize by means of a photochemically induced [4 + 4] cycloaddition of the anthracene moieties, whereas 1-Ln (Ln = Nd, Eu, Ho, Er) remain monomers. We propose three models, based on the matching of the energy levels between the Ln3+ ion and the paired or dimerized anthracene units in the energy-resonance crossing region, as well as on internal conversion-driven and intersystem crossing-driven energy transfer, which explain the Ln3+ ion regulated photophysics and photochemistry of the 1-Ln complexes.

8.
Chem Commun (Camb) ; 60(60): 7765-7768, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38973675

RESUMO

The solvothermal reaction of CuSO4·5H2O and a chiral R-pempH2 ligand (molar ratio 6 : 1) first forms the metastable intermediate [Cu24(OH)20(R-pempH)8(SO4)10(H2O)10.5]·35H2O (1), followed by the formation of the stable phase [Cu2(OH)(R-pempH)(SO4)(H2O)]·H2O (2). Compound 1 displays a novel 3D open-framework structure containing Cu12 cluster nodes and sulfate links, which can be converted to the layered compound 2. We also investigated the photothermal effects of both compounds.

9.
Proc Natl Acad Sci U S A ; 121(27): e2402143121, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38923993

RESUMO

The non-neural cholinergic system plays a critical role in regulating immune equilibrium and tissue homeostasis. While the expression of choline acetyltransferase (ChAT), the enzyme catalyzing acetylcholine biosynthesis, has been well documented in lymphocytes, its role in the myeloid compartment is less understood. Here, we identify a significant population of macrophages (Mϕs) expressing ChAT and synthesizing acetylcholine in the resolution phase of acute peritonitis. Using Chat-GFP reporter mice, we observed marked upregulation of ChAT in monocyte-derived small peritoneal Mϕs (SmPMs) in response to Toll-like receptor agonists and bacterial infections. These SmPMs, phenotypically and transcriptionally distinct from tissue-resident large peritoneal macrophages, up-regulated ChAT expression through a MyD88-dependent pathway involving MAPK signaling. Notably, this process was attenuated by the TRIF-dependent TLR signaling pathway, and our tests with a range of neurotransmitters and cytokines failed to induce a similar response. Functionally, Chat deficiency in Mϕs led to significantly decreased peritoneal acetylcholine levels, reduced efferocytosis of apoptotic neutrophils, and a delayed resolution of peritonitis, which were reversible with exogenous ACh supplementation. Intriguingly, despite B lymphocytes being a notable ChAT-expressing population within the peritoneal cavity, Chat deletion in B cells did not significantly alter the resolution process. Collectively, these findings underscore the crucial role of Mϕ-derived acetylcholine in the resolution of inflammation and highlight the importance of the non-neuronal cholinergic system in immune regulation.


Assuntos
Acetilcolina , Colina O-Acetiltransferase , Macrófagos Peritoneais , Peritonite , Animais , Colina O-Acetiltransferase/metabolismo , Colina O-Acetiltransferase/genética , Peritonite/imunologia , Peritonite/metabolismo , Camundongos , Macrófagos Peritoneais/metabolismo , Macrófagos Peritoneais/imunologia , Acetilcolina/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Fator 88 de Diferenciação Mieloide/genética , Camundongos Endogâmicos C57BL , Transdução de Sinais , Inflamação/metabolismo , Inflamação/patologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Receptores Toll-Like/metabolismo , Fagocitose , Macrófagos/metabolismo , Macrófagos/imunologia , Camundongos Knockout
10.
Cell Mol Immunol ; 21(10): 1120-1130, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38942796

RESUMO

Metabolic changes play a crucial role in determining the status and function of macrophages, but how lipid reprogramming in macrophages contributes to tumor progression is not yet fully understood. Here, we investigated the phenotype, contribution, and regulatory mechanisms of lipid droplet (LD)-laden macrophages (LLMs) in hepatocellular carcinoma (HCC). Enriched LLMs were found in tumor tissues and were associated with disease progression in HCC patients. The LLMs displayed immunosuppressive phenotypes (with extensive expression of TREM2, PD-L1, CD206, and CD163) and attenuated the antitumor activities of CD8+ T cells. Mechanistically, tumor-induced reshuffling of cellular lipids and TNFα-mediated uptake of tumoral fatty acids contribute to the generation of triglycerides and LDs in macrophages. LDs prolong LLM survival and promote CCL20 secretion, which further recruits CCR6+ Tregs to HCC tissue. Inhibiting LLM formation by targeting DGAT1 and DGAT2, which catalyze the synthesis of triglycerides, significantly reduced Treg recruitment, and delayed tumor growth in a mouse hepatic tumor model. Our results reveal the suppressive phenotypes and mechanisms of LLM enrichment in HCC and suggest the therapeutic potential of targeting LLMs for HCC patients.


Assuntos
Carcinoma Hepatocelular , Quimiocina CCL20 , Gotículas Lipídicas , Neoplasias Hepáticas , Macrófagos , Receptores CCR6 , Linfócitos T Reguladores , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/metabolismo , Humanos , Animais , Gotículas Lipídicas/metabolismo , Macrófagos/metabolismo , Macrófagos/imunologia , Quimiocina CCL20/metabolismo , Linfócitos T Reguladores/imunologia , Receptores CCR6/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Linhagem Celular Tumoral , Sobrevivência Celular , Masculino
11.
Small Methods ; : e2400671, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38803310

RESUMO

Cyclometalated iridium (Ir) complexes demonstrate impressive capabilities across a range of fields, including biology and photocatalysis, due to their tunable optical characteristics and structure flexibility. However, generating upconversion luminescence of Ir complexes under near-infrared light excitation is challenging. Herein, by employing lanthanide-doped upconversion nanoparticles (UCNPs) as the sensitizer, a new strategy is demonstrated to gain upconversion luminescence of Ir complexes via triplet energy transfer. This design relies on a rationally designed hybrid of core-shell structured NaYbF4:Tb@NaTbF4 UCNPs and new Ir phosphonate complexes, in which UCNPs can migrate upconverted energy to the surface of nanoparticles through Tb3+-mediated energy migration and then sensitize the upconversion luminescence of Ir complexes upon 980 nm excitation. Both experimental and theoretical investigations highlight the significance of triplet energy transfer from excited Tb3+ ions to the triplet state of Ir complexes in the sensitization of upconversion luminescence of Ir complexes. These findings may open exciting avenues for fabricating hybrid Ir materials with new functions and driving the development of UCNP-based nanomaterials.

12.
Dalton Trans ; 53(9): 4291-4298, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38345325

RESUMO

Studying the effect of morphology on the circularly polarized luminescence (CPL) of chiral molecular materials is important for the development of CPL-active materials for applications. Herein, we report that the morphology of Gd(NO3)3/R-,S-AnempH2 [AnempH2 = (1-anthrylethylamino)methylphosphonic acid] assemblies can be controlled by solvent modulation to form spiral bundles Gd(R-,S-AnempH)3·2H2O (R-,S-1), crystals Gd(R-,S-AnempH)3·2H2O (R-,S-2) and spindle-shaped particles Gd(R-,S-AnempH)3·3H2O·0.5DMF (R-,S-3) with similar chain structures. Interestingly, R-,S-1 are CPL active and show the highest value of dissymmetric factor among the three pairs of enantiomers (|glum| = 2.1 × 10-3), which is 2.8 times larger than that of R-,S-2, while R-,S-3 are CPL inactive with |glum| ≈ 0. This work provides a new route to control the morphology of chiral coordination polymers and improve their CPL performance.

13.
Cancer Lett ; 585: 216638, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38266805

RESUMO

Recent studies have suggested that therapeutic upregulation of CCAAT/enhancer binding protein α (C/EBPα) prevents hepatocellular carcinoma (HCC) progression. However, the mechanisms underlying this outcome are not fully understood. In this study, we investigated the expression and functional roles of C/EBPα in human HCC, with a focus on monocytes/macrophages (Mφs). Paraffin-embedded tissues were used to visualize C/EBPα expression and analyze the prognostic value of C/EBPα+ monocytes/Mφs in HCC patients. The underlying regulatory mechanisms were examined using human monocyte-derived Mφs. The results showed that the expression of C/EBPα on monocytes/Mφs was significantly decreased in intra-tumor tissues compared to the corresponding peri-tumor tissues. C/EBPα+ monocytes/Mφs displayed well-differentiation and antitumor capacities, and the accumulation of these cells in tissue was associated with antitumor immune responses and predicted longer overall survival (OS) of HCC patients. Mechanistic studies demonstrated that C/EBPα was required for Mφ maturation and HLA-DR, CD169 and CD86 expression, which initiates antitumor cytotoxic T-cell responses; however, these effects were inhibited by monocyte autocrine IL-6- and IL-1ß-induced suppression of mTOR1 signaling. Reprogramming Mφs via the upregulation of C/EBPα may provide a novel strategy for cancer immunotherapy in patients with HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Macrófagos/metabolismo , Monócitos/metabolismo
14.
Cancer Res ; 84(6): 841-854, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38231484

RESUMO

Triggering ferroptosis, an iron-dependent form of cell death, has recently emerged as an approach for treating cancer. A better understanding of the role and regulation of ferroptosis is needed to realize the potential of this therapeutic strategy. Here, we observed extensive activation of ferroptosis in hepatoma cells and human hepatocellular carcinoma (HCC) cases. Patients with low to moderate activation of ferroptosis in tumors had the highest risk of recurrence compared to patients with no or high ferroptosis. Upon encountering ferroptotic liver cancer cells, aggregated macrophages efficiently secreted proinflammatory IL1ß to trigger neutrophil-mediated sinusoidal vascular remodeling, thereby creating favorable conditions for aggressive tumor growth and lung metastasis. Mechanistically, hyaluronan fragments released by cancer cells acted via an NF-κB-dependent pathway to upregulate IL1ß precursors and the NLRP3 inflammasome in macrophages, and oxidized phospholipids secreted by ferroptotic cells activated the NLRP3 inflammasome to release functional IL1ß. Depleting either macrophages or neutrophils or neutralizing IL1ß in vivo effectively abrogated ferroptosis-mediated liver cancer growth and lung metastasis. More importantly, the ferroptosis-elicited inflammatory cellular network served as a negative feedback mechanism that led to therapeutic resistance to sorafenib in HCC. Targeting the ferroptosis-induced inflammatory axis significantly improved the therapeutic efficacy of sorafenib in vivo. Together, this study identified a role for ferroptosis in promoting HCC by triggering a macrophage/IL1ß/neutrophil/vasculature axis. SIGNIFICANCE: Ferroptosis induces a favorable tumor microenvironment and supports liver cancer progression by stimulating an inflammatory cellular network that can be targeted to suppress metastasis and improve the efficacy of sorafenib.


Assuntos
Carcinoma Hepatocelular , Ferroptose , Neoplasias Hepáticas , Neoplasias Pulmonares , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Sorafenibe/farmacologia , Proteína 3 que Contém Domínio de Pirina da Família NLR , Inflamassomos , Neoplasias Hepáticas/tratamento farmacológico , Inflamação/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Linhagem Celular Tumoral , Microambiente Tumoral
15.
Inorg Chem ; 62(51): 21044-21052, 2023 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-38051505

RESUMO

Lanthanide-based molecular materials showing efficient circularly polarized luminescence (CPL) activity with a high quantum yield are attractive due to their potential applications in data storage, optical sensors, and 3D displays. Herein we present an innovative method to achieve enhanced CPL activity and a high quantum yield by doping a chromophore ligand into a coordination polymer superhelix. A series of homochiral europium(III) phosphonates with a helical morphology were prepared with the molecular formula S-, R-[Eu(cyampH)3-3n(nempH)3n]·3H2O (S/R-Eu-n, n = 0-5%). The doping of chromophore ligand S- or R-nempH2 into superhelices of S/R-Eu-0% not only turned on the CPL activity with the dissymmetry factor |glum| on the order of 10-3 but also increased the quantum yield by about 14-fold. This work may shed light on the development of efficient CPL-active lanthanide-based coordination polymers for applications.

17.
Chem Sci ; 14(39): 10892-10901, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37829014

RESUMO

Inspired by natural biological systems, chiral or handedness inversion by altering external and internal conditions to influence intermolecular interactions is an attractive topic for regulating chiral self-assembled materials. For coordination polymers, the regulation of their helical handedness remains little reported compared to polymers and supramolecules. In this work, we choose the chiral ligands R-pempH2 (pempH2 = (1-phenylethylamino)methylphosphonic acid) and R-XpempH2 (X = F, Cl, Br) as the second ligand, which can introduce C-H⋯π and C-H⋯X interactions, doped into the reaction system of the Tb(R-cyampH)3·3H2O (cyampH2 = (1-cyclohexylethylamino)methylphosphonic acid) coordination polymer, which itself can form a right-handed superhelix by van der Waals forces, and a series of superhelices R-1H-x, R-2F-x, R-3Cl-x, and R-4Br-x with different doping ratios x were obtained, whose handedness is related to the second ligand and its doping ratio, indicating the decisive role of interchain interactions of different strengths in the helical handedness. This study could provide a new pathway for the design and self-assembly of chiral materials with controllable handedness and help the further understanding of the mechanism of self-assembly of coordination polymers forming macroscopic helical systems.

18.
Cancer Lett ; 577: 216426, 2023 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-37820992

RESUMO

The mechanisms underlying the involvement of long non-coding RNAs (lncRNAs) in the metastasis of small cell lung cancer (SCLC) remain largely unknown. Here, we identified that the lncRNA ITPR1-AS1 was upregulated in SCLC and lymph node metastasis tissues and positively correlated with SCLC malignant features. The overexpression of ITPR1-AS1 in SCLC was an independent risk factor for the overall survival of patients with SCLC. Our data confirmed that ITPR1-AS1 induces SCLC cell metastasis both in vitro and in vivo. Mechanistically, ITPR1-AS1 acts as a scaffold to enhance the interaction between SRC-associated in mitosis 68 kDa and heterogeneous nuclear ribonucleoprotein A1, which facilitates the alternative splicing of the H-Ras proto-oncogene (HRAS) pre-mRNA (P21HRAS). Moreover, we observed that ITPR1-AS1 could associate in a complex with and maintain the stability of DEAD-box polypeptide 3 (DDX3X), which inhibited the latter's ubiquitination and degradation. Our data provide evidence that ITPR1-AS1 activates the cRaf-MEK-ERK cascade by upregulating P21HRAS production and stabilizing DDX3X, to promote SCLC metastasis.


Assuntos
Neoplasias Pulmonares , RNA Longo não Codificante , Carcinoma de Pequenas Células do Pulmão , Humanos , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células/genética , RNA Helicases DEAD-box/genética , Regulação Neoplásica da Expressão Gênica , Receptores de Inositol 1,4,5-Trifosfato/genética , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Neoplasias Pulmonares/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Metástase Neoplásica , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , RNA Longo não Codificante/genética , Carcinoma de Pequenas Células do Pulmão/genética , Proteínas Proto-Oncogênicas c-raf/metabolismo
19.
J Am Chem Soc ; 145(44): 23948-23962, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37886816

RESUMO

Assembling macroscopic helices with controllable chirality and understanding their formation mechanism are highly desirable but challenging tasks for artificial systems, especially coordination polymers. Here, we utilize solvents as an effective tool to induce the formation of macroscopic helices of chiral coordination polymers (CPs) and manipulate their helical sense. We chose the Ni/R-,S-BrpempH2 system with a one-dimensional tubular structure, where R-,S-BrpempH2 stands for R-,S-(1-(4-bromophenyl)ethylaminomethylphosphonic acid). The morphology of the self-assemblies can be controlled by varying the cosolvent in water, resulting in the formation of twisted ribbons of R-,S-Ni(Brpemp)(H2O)·H2O (R-,S-2T) in pure H2O; needle-like crystals of R-,S-Ni(Brpemp)(H2O)2·1/3CH3CN (R-,S-1C) in 20 vol % CH3CN/H2O; nanofibers of R-,S-Ni(Brpemp)(H2O)·H2O (R-,S-3F) in 20-40 vol % methanol/H2O or ethanol/H2O; and superhelices of R-,S-Ni(Brpemp)(H2O)·H2O (R-,S-4H or 5H) in 40 vol % propanol/H2O. Interestingly, the helicity of the superhelix can be controlled by using a propanol isomer in water. For the Ni/R-BrpempH2 system, a left-handed superhelix of R-4H(M) was obtained in 40 vol % NPA/H2O, while a right-handed superhelix of R-5H(P) was isolated in 40 vol % IPA/H2O. These results were rationalized by theoretical calculations. Adsorption studies revealed the chiral recognition behavior of these compounds. This work may contribute to the development of chiral CPs with a macroscopic helical morphology and interesting functionalities.

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