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1.
Angew Chem Int Ed Engl ; : e202416695, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39365638

RESUMO

The demands of a sustainable chemical industry are a driving force for the development of heterogeneous catalytic platforms exhibiting facile catalyst recovery, recycling, and resilience to diverse reaction conditions. Homogeneous-to-heterogeneous catalyst transitions can be realized through the integration of efficient homogeneous catalysts within porous matrices. Herein, we offer a versatile approach to understanding how guest distribution and evolution impact the catalytic performance of heterogeneous host-guest catalytic platforms by implementing the resonance energy transfer (RET) concept using fluorescent model systems mimicking the steric constraints of targeted catalysts. Using the RET-based methodology, we mapped condition-dependent guest (re)distribution within a porous support on the example of modular matrices such as metal-organic frameworks (MOFs). Furthermore, we correlate RET results performed on the model systems with the catalytic performance of two MOF-encapsulated catalysts used to promote CO2 hydrogenation and ring-closing metathesis. Guests are incorporated using aperture-opening encapsulation, and catalyst redistribution is not observed under practical reaction conditions, showcasing a pathway to advance catalyst recyclability in the case of host-guest platforms. These studies represent the first generalizable approach for mapping the guest distribution in heterogeneous host-guest catalytic systems, providing a foundation for predicting and tailoring the performance of catalysts integrated into various porous supports.

2.
J Neurooncol ; 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39167244

RESUMO

OBJECTIVE: The surgical treatment of optic pathway gliomas (OPG) remains controversial, with visual outcomes often unpredictable. The present study explored surgical and clinical factors influencing visual acuity (VA) after OPG treatment and developed anatomical subtypes correlated with clinical symptoms. METHODS: Children with OPG who underwent initial partial tumor resection at Beijing Tiantan Hospital from January 2011 to December 2022 were retrospectively analyzed. Multivariate logistic regression and random forest analyses were performed to identify risk factors for post-treatment VA deterioration and a decision tree model was created based on significant factors. RESULTS: A total of 140 patients were enrolled. Multivariate logistic regression analysis identified surgical approach and initial VA as independent predictors of post-treatment VA deterioration (P < 0.05). Surgical approach, initial VA, and extent of tumor resection were the most significant factors for risk assessment and were included in the decision tree model, with surgical approach as the most important "root" node. The model demonstrated good predictive performance, with area under the curve values of 0.75 and 0.66 for the training and test datasets, respectively. A simple anatomical classification was developed, which revealed clinical characteristic differences among OPG types. Meanwhile, a correlation analysis of post-treatment visual deterioration was performed for each of the three anatomical types. CONCLUSION: This study offers a predictive model for visual outcomes following initial tumor-reduction surgery in OPG patients, which may help in visual outcomes risk stratification. Additionally, the anatomical classification effectively indicates OPG growth direction, offering potential insights into clinical symptoms.

3.
J Geriatr Cardiol ; 21(6): 658-668, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38973822

RESUMO

BACKGROUND: Stress hyperglycemia ratio (SHR) could provide accurate information on the acute status of hyperglycemia. The relationship between SHR and acute coronary syndrome (ACS) prognosis remains unclear. This study was conducted to identity the association between SHR and in-hospital outcomes in patients with ACS. METHODS: A total of 12,010 patients were eventually enrolled in the study. The relationship between SHR and in-hospital major adverse cardiovascular events (MACEs) was then modeled by restricted cubic spline (RCS) curves, and all patients were divided into three groups according to the results. The multivariate logistic regression analysis was used to determine the associations between the SHR and in-hospital outcomes, described as odds ratios (ORs) and 95% confidence intervals (CIs). Subgroup analyses were also performed on different diseases. RESULTS: The median age of this cohort was 63 (54, 71) years old, and 8942 (74.5%) were male. Group 1 was defined as SHR < 0.6 (n = 426), Group 2 was defined as SHR between 0.6 and 1 (n = 5821), and Group 3 was defined as SHR > 1 (n = 5763). Compared with Group 2, Group 1 (OR = 1.891, 95% CI: 1.028-3.479, P < 0.001) and Group 3 (OR = 1.868, 95% CI: 1.434-2.434, P < 0.001) had higher risks of suffering from in-hospital MACEs. SHR was associated with higher risks of in-hospital MACEs in the subgroups of DM [OR = 2.282, 95% CI: 1.477-3.524). CONCLUSIONS: Both low and high SHR levels were independently associated with in-hospital MACEs. Young males with DM, hypertension, and decreased renal function had much higher risks of suffering from SHR-correlated MACEs.

4.
Kaohsiung J Med Sci ; 40(8): 732-743, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38963317

RESUMO

An increasing number of elderly individuals are experiencing postoperative cognitive dysfunction (POCD) problems after undergoing hip replacement surgery, with gut microbiota metabolites playing a role in its pathogenesis. Among these, the specific effects of trimethylamine N-oxide (TMAO) on POCD are still unclear. This study aimed to explore the role of TMAO on cognitive dysfunction and underlying mechanisms in mice. The POCD model was created through femoral fracture surgery in elderly mice, followed by cognitive function assessments using the Morris Water Maze and Novel Object Recognition tests. The gut microbiota depletion and fecal microbiota transplantation were performed to examine the relationship between TMAO levels and cognitive outcomes. The effects of TMAO treatment on cognitive dysfunction, microglial activation, and inflammatory cytokine levels in the brain were also evaluated, with additional assessment of the role of microglial ablation in reducing TMAO-induced cognitive impairment. Elevated TMAO levels were found to be associated with cognitive decline in mice following femoral fracture surgery, with gut microbiota depletion mitigating both TMAO elevation and cognitive dysfunction. In contrast, fecal microbiota transplantation from postoperative mice resulted in accelerated cognitive dysfunction and TMAO accumulation in germ-free mice. Furthermore, TMAO treatment worsened cognitive deficits, neuroinflammation, and promoted microglial activation, which were reversed through the ablation of microglia. TMAO exacerbates cognitive dysfunction and neuroinflammation in POCD mice, with microglial activation playing a crucial role in this process. Our findings may provide new therapeutic strategies for managing TMAO-related POCD and improving the quality of life for elderly patients.


Assuntos
Disfunção Cognitiva , Modelos Animais de Doenças , Fraturas do Fêmur , Microbioma Gastrointestinal , Metilaminas , Animais , Metilaminas/metabolismo , Metilaminas/efeitos adversos , Camundongos , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/etiologia , Masculino , Fraturas do Fêmur/metabolismo , Fraturas do Fêmur/complicações , Microglia/metabolismo , Transplante de Microbiota Fecal , Camundongos Endogâmicos C57BL , Complicações Cognitivas Pós-Operatórias/metabolismo , Complicações Cognitivas Pós-Operatórias/etiologia , Citocinas/metabolismo , Encéfalo/metabolismo
5.
J Am Chem Soc ; 146(31): 21868-21876, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39051936

RESUMO

Recent advances in synthetic methods and monomer design have given access to precision carbohydrate polymers that extend beyond native polysaccharides. In this article, we present the synthesis of a class of chemically recyclable ester-linked pseudo-polysaccharides via the living anionic ring-opening polymerization of glucurono-1,6-lactones. Notably, the pseudo-polysaccharides exhibited defined chain-end groups, well-controlled molecular weights, and narrow molecular weight distributions, all hallmarks of living polymerization. Furthermore, we demonstrate that our approach is modular, as evidenced by tunable glass transition temperatures (Tg) and the ability to produce both amorphous and semicrystalline polymers by adjusting the monomer side chain structure. Lastly, we showcased the complete catalytic chemical recycling of these pseudo-polysaccharides back to the monomers. The flexibility of the polymerization and the recyclability of these pseudo-polysaccharides promote a sustainable circular economy while offering the potential to access polysaccharide-like materials with tunable thermal and mechanical properties.

6.
J Colloid Interface Sci ; 673: 797-806, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38906001

RESUMO

In response to the growing demand for clean, green, and sustainable energy sources, the development of cost-effective and durable high-activity overall water splitting electrocatalysts is urgently needed. In this study, the heterogeneous structure formed by the combination of FeCoNiP and FeNi-LDH was homogeneously dispersed onto CuO nanowires generated by in-situ oxidation of copper foam as a substrate using an electrodeposition method. This multilevel structure exhibits excellent bifunctional properties as an electrode material in alkaline solutions, for the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER) only 206 mV and 147 mV overpotentials are needed to achieve a current density of 100 mA cm-2 respectively. Full water electrolysis is thus enabled to take place at such a low cell voltage as 1.64 V to reach the current density of 100 mA cm-2, which exhibits a long-term stability of 30 h. These improved electrocatalytic performances stem from the construction of multilevel structures. The X-ray photoelectron spectroscopy suggests that strong electron transfer occurs between heterogeneous structures, thus facilitating the OER and HER process. The dispersion of CuO nanowires not only increases the electrochemically active surface areas but also improves the overall hydrophilic and aerophobic properties. This work highlights the positive effect of multilevel structure in the design of more efficient electrocatalysts and provides a reference for the preparation of other low-cost, high-activity bifunctional electrocatalysts.

7.
Nucleic Acids Res ; 52(14): 8063-8071, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-38917331

RESUMO

Enabling the precise control of protein functions with artificially programmed reaction patterns is beneficial for investigating biological processes. Although several strategies have been established that employ the programmability of nucleic acid, they have been limited to DNA hybridization without external stimuli or target binding. Here, we report an approach for the DNA-mediated control of the tripartite split-GFP assembly via aptamers with responsiveness to intracellular small molecules as stimuli. We designed a novel structure-switching aptamer-peptide conjugate as a hetero modulator for split GFP in response to ATP. By conjugating two peptides (S10/11) derived from the tripartite split-GFP to ATP aptamer, we achieved GFP reassembly using only ATP as a trigger molecule. The response to ATP at ≥4 mM concentrations indicated that it can be applied to respond to intracellular ATP in live cells. Furthermore, our hetero-modulator exhibited high and long-term stability, with a half-life of approximately four days in a serum stability assay, demonstrating resistance to nuclease degradation. We validated that our aptamer-modulator split GFP was successfully reconstituted in the cell in response to intracellular ATP levels. Our aptamer-modulated split GFP platform can be utilized to monitor a wide range of intracellular metabolites by replacing the aptamer sequence.


Assuntos
Trifosfato de Adenosina , Aptâmeros de Nucleotídeos , Proteínas de Fluorescência Verde , Peptídeos , Trifosfato de Adenosina/metabolismo , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Proteínas de Fluorescência Verde/genética , Humanos , Peptídeos/química , Peptídeos/metabolismo , DNA/química , DNA/metabolismo , Fluorescência , Células HeLa
8.
J Environ Manage ; 358: 120911, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38631164

RESUMO

Dissolved organic matter (DOM) is important in determining the drinking water treatment and the supplied water quality. However, a comprehensive DOM study for the whole water supply system is lacking and the potential effects of secondary water supply are largely unknown. This was studied using dissolved organic carbon (DOC), absorption spectroscopy, and fluorescence excitation-emission matrices-parallel factor analysis (EEM-PARAFAC). Four fluorescent components were identified, including humic-like C1-C2, tryptophan-like C3, and tyrosine-like C4. In the drinking water treatment plants, the advanced treatment using ozone and biological activated carbon (O3-BAC) was more effective in removing DOC than the conventional process, with the removals of C1 and C3 improved by 17.7%-25.1% and 19.2%-27.0%. The absorption coefficient and C1-C4 correlated significantly with DOC in water treatments, suggesting that absorption and fluorescence could effectively track the changes in bulk DOM. DOM generally remained stable in each drinking water distribution system, suggesting the importance of the treated water quality in determining that of the corresponding network. The optical indices changed notably between distribution networks of different treatment plants, which enabled the identification of changing water sources. A comparison of DOM in the direct and secondary water supplies suggested limited impacts of secondary water supply, although the changes in organic carbon and absorption indices were detected in some locations. These results have implications for better understanding the changes of DOM in the whole water supply system to help ensure the supplied water quality.


Assuntos
Abastecimento de Água , Qualidade da Água , Purificação da Água/métodos , Substâncias Húmicas/análise , Água Potável/química , Água Potável/análise , Carbono/análise
9.
Biomaterials ; 308: 122550, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38581762

RESUMO

Immune checkpoint blockade therapy represented by programmed cell death ligand 1 (PD-L1) inhibitor for advanced renal carcinoma with an objective response rate (ORR) in patients is less than 20%. It is attributed to abundant tumoral vasculature with abnormal structure limiting effector T cell infiltration and drug penetration. We propose a bispecific fibrous glue (BFG) to regulate tumor immune and vascular microenvironments simultaneously. The bispecific precursor glue peptide-1 (pre-GP1) can penetrate tumor tissue deeply and self-assemble into BFG in the presence of neuropilin-1 (NRP-1) and PD-L1. The resultant fibrous glue is capable of normalizing tumoral vasculature as well as restricting immune escape. The pre-GP1 retains a 6-fold higher penetration depth than that of antibody in the multicellular spheroids (MCSs) model. It also shows remarkable tumor growth inhibition (TGI) from 19% to 61% in a murine advanced large tumor model compared to the clinical combination therapy. In addition, in the orthotopic renal tumor preclinical model, the lung metastatic nodules are reduced by 64% compared to the clinically used combination. This pre-GP1 provides a promising strategy to control the progression and metastasis of advanced renal carcinoma.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Animais , Neoplasias Renais/patologia , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/terapia , Neoplasias Renais/imunologia , Humanos , Camundongos , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/imunologia , Carcinoma de Células Renais/terapia , Carcinoma de Células Renais/tratamento farmacológico , Linhagem Celular Tumoral , Microambiente Tumoral/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Feminino , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/metabolismo
10.
J Sci Food Agric ; 104(10): 5973-5981, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38436499

RESUMO

BACKGROUND: Baijiu is a well-known alcoholic beverage in China and the quality is determined by various microorganisms during the fermentation process. Yeast is one of the most important microorganisms in the fermentation of baijiu. It has a strong esterification capacity and also affects the aroma. RESULTS: High-throughput sequencing results showed that the fermented grains (jiupei) during baijiu production were mainly composed of eight highly abundant yeast species. The species and abundance of yeasts changed significantly with the fermentation process. The flavor of 30 yeast strains in the jiupei was determined by a sniffing test and gas chromatography-mass spectrometry (GC-MS). The strain with the highest flavor substance content (2.34 mg L-1), named YX3205, was identified as Clavispora lusitaniae. Tolerance results showed that C. lusitaniae YX3205 can tolerate up to 15% (v v-1) ethanol. In a solid-state simulated fermentation experiment, the content of 24 flavor substances was significantly increased in the fortified group, and the total ester content reached 4240.73 µg kg-1, which was 2.8 times higher than that of the control group. CONCLUSION: The present study demonstrated the potential of C. lusitaniae YX3205 to enhance the flavor of baijiu, thereby serving as a valuable strain for the improvement of the flavor quality of baijiu. © 2024 Society of Chemical Industry.


Assuntos
Bebidas Alcoólicas , Fermentação , Aromatizantes , Paladar , Leveduras , Aromatizantes/metabolismo , Aromatizantes/química , Leveduras/metabolismo , Leveduras/classificação , Leveduras/genética , Bebidas Alcoólicas/análise , Bebidas Alcoólicas/microbiologia , China , Cromatografia Gasosa-Espectrometria de Massas , Grão Comestível/química , Grão Comestível/microbiologia , Grão Comestível/metabolismo , Etanol/metabolismo , Etanol/análise
11.
J Am Chem Soc ; 146(12): 7963-7970, 2024 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-38483110

RESUMO

Cellulose serves as a sustainable biomaterial for a wide range of applications in biotechnology and materials science. While chemical and enzymatic glycan assembly methods have been developed to access modest quantities of synthetic cellulose for structure-property studies, chemical polymerization strategies for scalable and well-controlled syntheses of cellulose remain underdeveloped. Here, we report the synthesis of precision cellulose via living cationic ring-opening polymerization (CROP) of glucose 1,2,4-orthopivalates. In the presence of dibutyl phosphate as an initiator and triflic acid as a catalyst, precision cellulose with well-controlled molecular weights, defined chain-end groups, and excellent regio- and stereospecificity was readily prepared. We further demonstrated the utility of this method through the synthesis of precision native d-cellulose and rare precision l-cellulose.


Assuntos
Celulose , Glucose , Celulose/química , Polimerização , Glucose/química , Polissacarídeos , Cátions
12.
Sci Total Environ ; 926: 171963, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38537835

RESUMO

Significant research is focused on the ability of riparian zones to reduce groundwater nitrate contamination. Owing to the extremely high redox activity of nitrate, naturally existing electron donors, such as organic matter and iron minerals, are crucial in facilitating nitrate reduction in the riparian zone. Here, we examined the coexistence of magnetite, an iron mineral, and nitrate, a frequently observed coexisting system in sediments, to investigate nitrate reduction features at various C/N ratios and evaluate the response of microbial communities to these settings. Additionally, we aimed to use this information as a foundation for examining the effect of nutritional conditions on the nitrate reduction process in magnetite-present environments. These results emphasise the significance of organic matter in enabling dissimilatory nitrate reduction to ammonium (DNRA) and enhancing the connection between nitrate reduction and iron in sedimentary environments. In the later phases of nitrate reduction, nitrogen fixation was the prevailing process in low-carbon environments, whereas high-carbon environments tended to facilitate the breakdown of organic nitrogen. High-throughput sequencing analysis revealed a robust association between C/N ratios and alterations in microbial community composition, providing insights into notable modifications in essential functioning microorganisms. The nitrogen-fixing bacterium Ralstonia is more abundant in ecosystems with scarce organic matter. In contrast, in settings rich in organic matter, microorganisms, such as Acinetobacter and Clostridia, which may produce ammonia, play crucial roles. Moreover, the population of iron bacteria grows in such an environment. Hence, this study proposes that C/N ratios can influence Fe(II)/Fe(III) conversions and simultaneously affect the process of nitrate reduction by shaping the composition of specific microbial communities.


Assuntos
Compostos de Amônio , Nitratos , Nitratos/análise , Óxido Ferroso-Férrico , Rios , Ecossistema , Compostos Férricos , Desnitrificação , Ferro , Nitrogênio , Carbono , Oxirredução
13.
J Hazard Mater ; 469: 133884, 2024 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-38412647

RESUMO

Whether coexisting microplastics (MPs) affect the ecological and health risks of cadmium (Cd) in soils is a cutting-edge scientific issue. In this study, four typical Chinese soils were prepared as artificially Cd-contaminated soils with/without aged polystyrene (PS). TCLP and in vitro PBET model were used to determine the leachability (ecological risk) and oral bioaccessibility (human health risk) of soil Cd. The mechanisms by which MPs influence soil Cd were discussed from direct and indirect perspectives. Results showed that there was no significant difference in the leachability of soil Cd with/without aged PS. Additionally, aged PS led to a significant decrease in the bioaccessibility of soil Cd in gastric phase, but not in small intestinal phase. The increase in surface roughness and the new characteristic peaks (e.g., Si-O-Si) of aged PS directly accounted for the change in Cd bioaccessibility. The change in organic matter content indirectly accounted for the exceptional increase in Cd bioaccessibility of black soil with aged PS in small intestinal phase. Furthermore, the changes in cation exchange capacity and Cd mobility factor caused by aged PS explained the change in Cd leachability. These results contribute to a deeper understanding about environmental and public health in complicated emerging scenarios.


Assuntos
Cádmio , Poluentes do Solo , Humanos , Idoso , Cádmio/toxicidade , Cádmio/análise , Microplásticos/toxicidade , Plásticos , Poliestirenos/toxicidade , Solo , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , Disponibilidade Biológica
14.
J Am Chem Soc ; 146(8): 5056-5062, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38345300

RESUMO

Cyclic ketene acetals (CKAs) are among the most well-studied monomers for radical ring-opening polymerization (rROP). However, ring-retaining side reactions and low reactivities in homopolymerization and copolymerization remain significant challenges for the existing CKAs. Here, we report that a class of monosaccharide CKAs can be facilely prepared from a short and scalable synthetic route and can undergo quantitative, regiospecific, and stereoselective rROP. NMR analyses and degradation experiments revealed a reaction mechanism involving a propagating radical at the C2 position of pyranose with different monosaccharides exhibiting distinct stereoselectivity in the radical addition of the monomer. Furthermore, the addition of maleimide was found to improve the incorporation efficiency of monosaccharide CKA in the copolymerization with vinyl monomers and produced unique degradable terpolymers with carbohydrate motifs in the polymer backbone.

15.
Phytochemistry ; 220: 113992, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38301947

RESUMO

Seven undescribed neovibsane-type diterpenoids (1-7) were isolated from the leaves of Viburnum odoratissimum. Their planar structures and relative configurations were elucidated based on a combination of 1D and 2D NMR analysis. The absolute configurations were confirmed by Rh2(OCOCF3)4-induced ECD analysis and comparison of experimental and TDDFT-calculated ECD spectrum. Based on the empirical results of the ECD of in situ formed Rh-complexes, rapid determination of the absolute configuration of C-14 within vibsane-type diterpenoids was proposed. In addition, 3 exhibited a high neuroblastoma cell protective effect of 81.8 % at 50 µM (the control group showed a neuroblastoma cell protective effect of 56.2 % at 50 µM).


Assuntos
Diterpenos , Neuroblastoma , Viburnum , Viburnum/química , Estrutura Molecular , Diterpenos/química , Folhas de Planta/química
16.
Huan Jing Ke Xue ; 45(1): 470-479, 2024 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-38216496

RESUMO

Contaminants such as microplastics (MPs) and heavy metals are commonly found in soils, both of which are extremely difficult to degrade and can easily form compound contamination, altering the physicochemical properties of the soil and thus potentially changing the growth and physiological and ecological characteristics of plants. In order to study the effects of the combined contamination of soil MPs and heavy metals on soil properties and plant growth, polystyrene microplastics (PS-MPs) with a particle size of 3 µm and the heavy metal cadmium were selected in the study. The changes in the physicochemical properties of soil and their effects on lettuce (Lactuca sativa) seed germination and seedling growth were studied at various exposure concentrations of PS-MPs (0, 10, 50, 100, 200, and 400 mg·kg-1) and combined with different Cd contamination concentrations (0, 1.2, and 6.0 mg·kg-1), respectively. The results showed that soil organic matter (SOM), available phosphorus (AP), alkali-hydrolysable nitrogen (AHN), and available kalium (AK) showed significant decreases as the intensity of PS-MPs combined with Cd contamination increased. Simultaneously, PS-MPs combined with Cd contamination also significantly reduced the germination rate of lettuce seeds, but low concentrations of PS-MPs slowed down the effect of Cd (6.0 mg·kg-1) contamination on lettuce seeds, and high concentrations of PS-MPs enhanced the effect of Cd (6.0 mg·kg-1). The fresh weight, dry weight, and plant height of lettuce seedlings showed an increasing and then decreasing trend with increasing exposure to PS-MPs. Chlorophyll content, superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) showed a decreasing trend, whereas malondialdehyde (MDA) content showed an overall increasing trend under different Cd concentrations. The main physicochemical indicators of the soil were negatively correlated with MDA of lettuce seedlings, whereas other indicators of the seedlings were positively correlated. The combined contamination of PS-MPs and Cd could affect the germination of plant seeds and the physiological and ecological characteristics of seedlings by changing the physicochemical properties of the soil. Both exposure to single PS-MPs contaminants and the combination of PS-MPs with Cd inhibited the germination of lettuce seeds and affected the physiological activities of their seedlings, and the inhibition was significantly increased with increasing exposure. Low exposure to PS-MPs or the combination of PS-MPs with Cd contamination exhibited a promotive effect on lettuce seedling growth. High exposure to PS-MPs combined with Cd contamination exhibited significant ecological effects on lettuce seedlings, and high exposure to PS-MPs exacerbated the ecotoxicological effects of Cd contaminants on lettuce seedlings, and PS-MPs and Cd exhibited synergistic effects. The results can provide some reference for assessing the ecological effects of MPs and heavy metal pollution in soil-plant systems.


Assuntos
Metais Pesados , Poluentes do Solo , Cádmio/toxicidade , Cádmio/metabolismo , Microplásticos , Lactuca , Plásticos , Poliestirenos , Solo , Metais Pesados/metabolismo , Plântula , Poluentes do Solo/análise
17.
Bioorg Chem ; 143: 107007, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38039928

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide, with high mortality and poor prognosis. WBDC-1 is a novel highly oxidized germacranolide from the Elephantopus tomentosus in our previous work, which has excellent anti-HCC activity, but the detailed mechanism is still unclear. In this study, we found that WBDC-1 was able to inhibit the proliferation and colony formation of Hep3B and HepG2 cells, as well as the cell migration ability and EMT. In addition, WBDC-1 showed no obvious toxicity to normal liver epithelial cells L-02. The potential targets of WBDC-1 were predicted by network pharmacology, and the following verified experiments showed that WBDC-1 exerted anti-HCC effect by targeting EGFR. Mechanismly, subsequent biological analysis showed that WBDC-1 can inhibit EGFR and its downstream RAS/RAF/MEK/ERK and PI3K/AKT signaling pathways. Overexpression of EGFR reversed the anticancer properties of WBDC-1. Consistent with in vitro experiments, WBDC-1 was able to inhibit tumor growth and was non-toxic in xenograft tumor models. In summary, this study revealed a potential tumor suppressive mechanism of WBDC-1 and provided a novel strategy for HCC treatment. It also laid a foundation for further research on the anti-tumor effect of highly oxidized germacranolides.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Sesquiterpenos de Germacrano , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Receptores ErbB
20.
Angew Chem Int Ed Engl ; 62(50): e202311601, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37870901

RESUMO

Boron trifluoride (BF3 ) is a highly corrosive gas widely used in industry. Confining BF3 in porous materials ensures safe and convenient handling and prevents its degradation. Hence, it is highly desired to develop porous materials with high adsorption capacity, high stability, and resistance to BF3 corrosion. Herein, we designed and synthesized a Lewis basic single-crystalline hydrogen-bond crosslinked organic framework (HC OF-50) for BF3 storage and its application in catalysis. Specifically, we introduced self-complementary ortho-alkoxy-benzamide hydrogen-bonding moieties to direct the formation of highly organized hydrogen-bonded networks, which were subsequently photo-crosslinked to generate HC OFs. The HC OF-50 features Lewis basic thioether linkages and electron-rich pore surfaces for BF3 uptake. As a result, HC OF-50 shows a record-high 14.2 mmol/g BF3 uptake capacity. The BF3 uptake in HC OF-50 is reversible, leading to the slow release of BF3 . We leveraged this property to reduce the undesirable chain transfer and termination in the cationic polymerization of vinyl ethers. Polymers with higher molecular weights and lower polydispersity were generated compared to those synthesized using BF3 ⋅ Et2 O. The elucidation of the structure-property relationship, as provided by the single-crystal X-ray structures, combined with the high BF3 uptake capacity and controlled sorption, highlights the molecular understanding of framework-guest interactions in addressing contemporary challenges.

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