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1.
J Am Chem Soc ; 146(3): 2275-2285, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38215226

RESUMO

The construction of structurally well-defined supramolecular hosts to accommodate catalytically active species within a cavity is a promising way to address catalyst deactivation. The resulting supramolecular catalysts can significantly improve the utilization of catalytic sites, thereby achieving a highly efficient chemical conversion. In this study, the Co-metalated phthalocyanine (Pc-Co) was successfully confined within a tetragonal prismatic metallacage, leading to the formation of a distinctive type of supramolecular photocatalyst (Pc-Co@Cage). The host-guest architecture of Pc-Co@Cage was unambiguously elucidated by single-crystal X-ray diffraction (SCXRD), NMR, and ESI-TOF-MS, revealing that the single cobalt active site can be thoroughly isolated within the space-restricted microenvironment. In addition, we found that Pc-Co@Cage can serve as a homogeneous supramolecular photocatalyst that displays high CO2 to CO conversion in aqueous media under visible light irradiation. This supramolecular photocatalyst exhibits an obvious improvement in activity (TONCO = 4175) and selectivity (SelCO = 92%) relative to the nonconfined Pc-Co catalyst (TONCO = 500, SelCO = 54%). The present strategy provided a rare example for the construction of a highly active, selective, and stable photocatalyst for CO2 reduction through a cavity-confined molecular catalyst within a discrete metallacage.

2.
BMC Immunol ; 25(1): 56, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39169307

RESUMO

BACKGROUND: Leukemia inhibitory factor (LIF) is a multifunctional member of the IL-6 cytokine family that activates downstream signaling pathways by binding to the heterodimer consisting of LIFR and gp130 on the cell surface. Previous research has shown that LIF is highly expressed in various tumor tissues (e.g. pancreatic cancer, breast cancer, prostate cancer, and colorectal cancer) and promotes cancer cell proliferation, migration, invasion, and differentiation. Moreover, the overexpression of LIF correlates with poor clinicopathological characteristics. Therefore, we hypothesized that LIF could be a promising target for the treatment of cancer. In this work, we developed the antagonist antibody 1G11 against LIF and investigated its anti-tumor mechanism and its therapeutic efficacy in mouse models. RESULTS: A series of single-chain variable fragments (scFvs) targeting LIF were screened from a naive human scFv phage library. These scFvs were reconstructed in complete IgG form and produced by the mammalian transient expression system. Among the antibodies, 1G11 exhibited the excellent binding activity to human, cynomolgus monkey and mouse LIF. Functional analysis demonstrated 1G11 could block LIF binding to LIFR and inhibit the intracellular STAT3 phosphorylation signal. Interestingly, 1G11 did not block LIF binding to gp130, another LIF receptor that is involved in forming the receptor complex together with LIFR. In vivo, intraperitoneal administration of 1G11 inhibited tumor growth in CT26 and MC38 models of colorectal cancer. IHC analysis demonstrated that p-STAT3 and Ki67 were decreased in tumor tissue, while c-caspase 3 was increased. Furthermore, 1G11 treatment improves CD3+, CD4 + and CD8 + T cell infiltration in tumor tissue. CONCLUSIONS: We developed antagonist antibodies targeting LIF/LIFR signaling pathway from a naive human scFv phage library. Antagonist anti-LIF antibody exerts antitumor effects by specifically reducing p-STAT3. Further studies revealed that anti-LIF antibody 1G11 increased immune cell infiltration in tumor tissues.


Assuntos
Fator Inibidor de Leucemia , Anticorpos de Cadeia Única , Animais , Humanos , Anticorpos de Cadeia Única/imunologia , Anticorpos de Cadeia Única/farmacologia , Camundongos , Fator Inibidor de Leucemia/imunologia , Fator Inibidor de Leucemia/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT3/imunologia , Receptor gp130 de Citocina/imunologia , Receptor gp130 de Citocina/metabolismo , Receptor gp130 de Citocina/antagonistas & inibidores , Biblioteca de Peptídeos , Transdução de Sinais , Feminino , Macaca fascicularis , Camundongos Endogâmicos BALB C , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Small ; 20(38): e2401308, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38773889

RESUMO

Incorporating ultralow loading of nanoparticles into polymers has realized increases in dielectric constant and breakdown strength for excellent energy storage. However, there are still a series of tough issues to be dealt with, such as organic solvent uses, which face enormous challenges in scalable preparation. Here, a new strategy of dual in situ synthesis is proposed, namely polymerization of polyethylene terephthalate (PET) synchronizes with growth of calcium borate nanoparticles, making polyester nanocomposites from monomers directly. Importantly, this route is free of organic solvents and surface modification of nanoparticles, which is readily accessible to scalable synthesis of polyester nanocomposites. Meanwhile, uniform dispersion of as ultralow as 0.1 wt% nanoparticles and intense bonding at interfaces have been observed. Furthermore, the PET-based nanocomposite displays obvious increases in both dielectric constant and breakdown strength as compared to the neat PET. Its maximum discharged energy density reaches 15 J cm-3 at 690 MV m-1 and power density attains 218 MW cm-3 under 150 Ω resistance at 300 MV m-1, which is far superior to the current dielectric polymers that can be produced at large scales. This work presents a scalable, safe, low-cost, and environment-friendly route toward polymer nanocomposites with superior capacitive performance.

4.
J Org Chem ; 89(1): 624-632, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38115588

RESUMO

A solvent-controllable organo-photoredox-catalyzed C-F bond activation for masked formylation of α-trifluoromethyl alkenes with low-priced 1,3-dioxolane as masked formyl radical equivalent has been described. Consequently, a diversity of masked formylated gem-difluoroalkenes and monofluoroalkenes are constructed in moderate to high yields. This approach merits readily available starting materials, mild reaction conditions, and broad substrate scope. The feasibility of this approach has been highlighted by the one-pot masked formylation/hydrolysis sequence to form γ,γ-difluoroallylic aldehydes and late-stage modification of pharmaceutical and natural product derivatives.

5.
J Org Chem ; 89(6): 4056-4066, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38449357

RESUMO

An organo-photoredox catalyzed gem-difluoroallylation of glycine with α-trifluoromethyl alkenes via direct C(sp3)-H functionalization of glycine and C-F bond activation of α-trifluoromethyl alkenes has been described. As a consequence, a broad range of gem-difluoroalkene-containing unnatural amino acids are afforded in moderate to excellent yields. This reaction exhibits multiple merits such as readily available starting materials, broad substrate scope, and mild reaction conditions. The feasibility of this reaction has been highlighted by the late-stage modification of several peptides as well as the improved in vitro antifungal activity of compound 3v toward Valsa mali compared to that with commercial azoxystrobin.


Assuntos
Aminoácidos , Glicina , Alcenos , Peptídeos , Catálise
6.
Org Biomol Chem ; 22(27): 5561-5568, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38916128

RESUMO

An organo-photoredox catalyzed gem-difluoroallylation of both acyclic and cyclic ketone derivatives with α-trifluoromethyl alkenes has been demonstrated, thus giving access to a diverse set of gem-difluoroalkenes in moderate to high yields. Pro-aromatic dihydroquinazolinones can be either pre-formed or in situ generated for ketone activation. This reaction is characterized by readily available starting materials, mild reaction conditions, and broad substrate scope. The feasibility of this reaction has been highlighted by the late-stage modification of several natural products and drug-like molecules as well as the in vitro antifungal activity.

7.
Environ Sci Technol ; 58(9): 4357-4367, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38326940

RESUMO

Gas nanobubbles used for water treatment and recovery give rise to great concern for their unique advantages of less byproducts, higher efficiency, and environmental friendliness. Nanoscale zerovalent iron (nZVI), which has also been widely explored in the field of environmental remediation, can generate gas hydrogen by direct reaction with water. Whether nanoscale hydrogen bubbles can be produced to enhance the pollution removal of the nZVI system is one significant concern involved. Herein, we report direct observations of in situ generation of hydrogen nanobubbles (HNBs) from nZVI in water. More importantly, the formed HNBs can enhance indeed the reduction of Se(IV) beyond the chemical reduction ascribed to Fe(0), especially in the anaerobic environment. The possible mechanism is that HNBs enhance the reducibility of the system and promote electron transport in the solution. This study demonstrates a unique function of HNBs combined with nZVI for the pollutant removal and a new approach for in situ HNB generation for potential applications in the fields of in situ remediation agriculture, biotechnology, medical treatment, health, etc.


Assuntos
Poluentes Ambientais , Recuperação e Remediação Ambiental , Poluentes Químicos da Água , Purificação da Água , Ferro
8.
Genet Sel Evol ; 56(1): 60, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39227836

RESUMO

BACKGROUND: Accurate breed identification is essential for the conservation and sustainable use of indigenous farm animal genetic resources. In this study, we evaluated the phylogenetic relationships and genomic breed compositions of 13 sheep breeds using SNP and InDel data from whole genome sequencing. The breeds included 11 Chinese indigenous and 2 foreign commercial breeds. We compared different strategies for breed identification with respect to different marker types, i.e. SNPs, InDels, and a combination of SNPs and InDels (named SIs), different breed-informative marker detection methods, and different machine learning classification methods. RESULTS: Using WGS-based SNPs and InDels, we revealed the phylogenetic relationships between 11 Chinese indigenous and two foreign sheep breeds and quantified their purities through estimated genomic breed compositions. We found that the optimal strategy for identifying these breeds was the combination of DFI_union for breed-informative marker detection, which integrated the methods of Delta, Pairwise Wright's FST, and Informativeness for Assignment (namely DFI) by merging the breed-informative markers derived from the three methods, and KSR for breed assignment, which integrated the methods of K-Nearest Neighbor, Support Vector Machine, and Random Forest (namely KSR) by intersecting their results. Using SI markers improved the identification accuracy compared to using SNPs or InDels alone. We achieved accuracies over 97.5% when using at least the 1000 most breed-informative (MBI) SI markers and even 100% when using 5000 SI markers. CONCLUSIONS: Our results provide not only an important foundation for conservation of these Chinese local sheep breeds, but also general approaches for breed identification of indigenous farm animal breeds.


Assuntos
Cruzamento , Mutação INDEL , Polimorfismo de Nucleotídeo Único , Ovinos , Animais , Cruzamento/métodos , China , Genética Populacional/métodos , Filogenia , Ovinos/genética , Sequenciamento Completo do Genoma/métodos , Sequenciamento Completo do Genoma/veterinária
9.
J Thromb Thrombolysis ; 57(1): 29-38, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37351822

RESUMO

BACKGROUND: VT (Ventricular Thrombus) is a serious complication of dilated cardiomyopathy (DCM). Our goal is to develop a nomogram for personalized prediction of incident VT in DCM patients. METHODS: 1267 patients (52.87 ± 11.75 years old, 73.8% male) were analyzed retrospectively from January 01, 2015, to December 31, 2020. A nomogram model for VT risk assessment was established using minimum absolute contraction and selection operator (LASSO) and multivariate logistic regression analysis, and its effectiveness was validated by internal guidance. The model was evaluated by the area under the receiver operating characteristic curve (AUC), calibration curves, and decision curve analysis (DCA). We compared the performance in predicting VT between nomogram and CHA2DS2, CHA2DS2- VASc or ATRIA by AUC, akaike information criterion (AIC), bayesian information criterion (BIC), net reclassification index (NRI), and integrated discrimination index (IDI). RESULTS: 89 patients (7.02%) experienced VT. Multivariate logistic regression analysis revealed that age, left ventricular ejection fraction (LVEF), uric acid (UA), N-terminal precursor B-type diuretic peptide (NT-proBNP), and D-dimer (DD) were important independent predictors of VT. The nomogram model correctly separates patients with and without VT, with an optimistic C score of 0.92 (95%CI: 0.90-0.94) and good calibration (Hosmer-Lemeshow χ2 = 11.51, P = 0.12). Our model showed improved prediction of VT compared to CHA2DS2, CHA2DS2-VASc or ATRIA (all P < 0.05). CONCLUSIONS: The novel nomogram demonstrated better than presenting scores and showed an improvement in predicting VT in DCM patients.


Assuntos
Cardiomiopatia Dilatada , Cardiopatias , Trombose , Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Feminino , Teorema de Bayes , Cardiomiopatia Dilatada/complicações , Cardiomiopatia Dilatada/diagnóstico , Nomogramas , Estudos Retrospectivos , Volume Sistólico , Função Ventricular Esquerda , Trombose/diagnóstico , Trombose/etiologia
10.
BMC Public Health ; 24(1): 1931, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39026191

RESUMO

BACKGROUND: Nasopharyngeal carcinoma (NPC) is 22nd most common cancer that occurs all over the world, but the prevalence rate can exhibit significant geographical differences. The Global Burden of Disease (GBD) database provides data related to the incidence, mortality, and disease burden of NPC worldwide from 1990 to 2019. We have designed this study in order to evaluate the potential effectiveness of health care policies and strategies for NPC prevention, diagnosis and treatment in different countries or regions around the world. METHODS: We used for the first time two distinct indicators, EAPC-ASIR and EACP-ASDR, to perform cluster analysis on 200 countries or regions around the world. RESULTS: 200 countries or regions could be divided into five diverse groups. Group 1: The incidence rate showed an increasing trend whereas the mortality rate depicted a decreasing trend. Group 2: Morbidity as well as mortality showed a slight increase; Group 3: Morbidity as well as mortality increased significantly; Group 4: Morbidity and mortality decreased significantly; Group 5: Both morbidity as well as mortality decreased slightly. Moreover, in the context of a global decline in NPC incidence, mortality and disease burden, Group 3 countries, including: "Turkmenistan", "Bosnia and Herzegovina", "Dominican Republic", "Bulgaria", "Lesotho", "Cabo Verde", "Romania", "Cuba", "Jamaica", "Azerbaijan", "Uzbekistan", "Chad", "Belize" and "Ukraine" displayed a significant increase in morbidity, mortality, and disease burden, thus indicating a dangerous trend. CONCLUSION: It is suggested that the medical and health policies formulated by the countries in Group 3 for NPC, as well as their capacity for conducting censuses, preventing, diagnosing, and treating diseases, need to be substantially strengthened.


Assuntos
Saúde Global , Neoplasias Nasofaríngeas , Humanos , Neoplasias Nasofaríngeas/epidemiologia , Neoplasias Nasofaríngeas/mortalidade , Saúde Global/estatística & dados numéricos , Medição de Risco , Incidência , Carga Global da Doença , Análise por Conglomerados , Carcinoma Nasofaríngeo/epidemiologia , Carcinoma Nasofaríngeo/diagnóstico , Carcinoma Nasofaríngeo/mortalidade
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