Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 349
Filtrar
1.
Small ; : e2207720, 2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36732904

RESUMO

Conjugated coordination polymers (CCPs) have attracted extensive attention for various applications related to energy storage and conversion in the past few years, despite that there are many CCPs with unclear chemical states and structures. Here, linear CCPs (LCCPs), with metal-O4 active sites grown on carbon paper (CP) for oxygen evolution reaction (OER), are presented. The LCCPs with high crystallinity and simple structures exhibit the order of electrocatalytic activity of Co-O4  > Ni-O4  > Fe-O4 in terms of the metal-O4 centers. The Co-based LCCP shows higher OER performance (263 mV at 10 mA cm-2 ) and better durability (90 h at 30 mA cm-2 ) than commercial IrO2 /CP. The structures and chemical states of LCCPs are carefully investigated, and density functional theory is used to reveal the mechanism of OER at the central metal site. This investigation into LCCPs provides new sights for a better understanding of CCPs and expands the applications of LCCPs with metal-O4 sites.

2.
Water Res ; 232: 119651, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36731203

RESUMO

Fluoroquinolone antibiotics (FQs) have been widely detected in the sediments due to vast production and consumption. In this study, the transformation of FQs was investigated in the presence of sediment mackinawite (FeS) under ambient conditions. Moreover, the role of dissolved oxygen was evaluated for the enhanced degradation of FQs induced by FeS. Our results demonstrated that typical FQs (i.e., flumequine, enrofloxacin and ciprofloxacin) could be efficiently adsorbed and degraded by FeS under neutral pH conditions. As indicated by the results of electron paramagnetic resonance analysis (EPR) and free radicals quenching experiments, hydroxyl radical and superoxide radical anions were identified as the dominant reactive species responsible for FQs degradation. Based on the results of product analysis and theoretical calculation, the degradation of FQs mainly occurred at the piperazine ring and quinolone structure. Our results show that FQs could be efficiently removed by FeS, which benefits understanding the transformation of antibiotics in the sediments, and even sheds light on the remediation of organic pollutants contaminated soils.

3.
Cancers (Basel) ; 15(2)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36672336

RESUMO

Cuproptosis is a copper-induced form of mitochondrial cell death which is engaged in the proliferation and migration of a variety of tumors. Nevertheless, the role of cuproptosis in tumor microenvironment (TME) remodeling and antitumor therapy is still poorly understood. We characterized two diverse cuproptosis-associated molecular isoforms in CRC which exhibit distinct prognostic and TME characteristics. Subsequently, we constructed a cuproptosis-associated prognostic model containing five genes and divided the patients into a high CPS-score group and a low CPS-score group. Univariate and multivariate Cox analyses showed that the CPS score could be used as an independent prognostic factor. The nomogram, and its consequent calibration curves, indicated that this prognostic signature had good predictive power for CRC. The analysis of single-cell sequencing data showed the significant expression of HES4 and SPHK1 in various immune and stromal (including fibroblasts) cells. Further studies showed that tumor mutational burden (TMB), high microsatellite instability (MSI-H) ratio, immune checkpoint blockade (ICB), and human leukocyte antigen (HLA) gene expression all positively correlated with the CPS score, predicting a better reaction to immunotherapy in high CPS-core patients. The CPS score constructed from cuproptosis subtypes can be used as a predictive tool to evaluate the prognosis of CRC patients and their response to immunotherapy.

4.
Water Res ; 230: 119580, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36638730

RESUMO

Linear and branched isomers of per- and polyfluoroalkyl substances (PFASs) are simultaneously present in the environment. However, isomer profiles of PFASs in municipal wastewater treatment plants (WWTPs) are still unknown because of the limitations of standards. Here, influent and effluent samples from 148 municipal WWTPs in China were collected. Ion mobility spectrometry was introduced into high-resolution mass spectrometry-based suspect screening methods to identify the target and suspect PFAS isomers. A total of 38 branched isomers of 14 typical PFASs were identified in wastewater samples. Linear PFASs had higher detection rates (22.3%-100%) than branched isomers (2.0%-98%). Compared to the influents, proportions of branched isomers of most PFASs (except for perfluoropentanoic acid and perfluorohexanoic acid) increased in the effluents. The conventional biological treatment processes (such as anaerobic-anoxic-aerobic and oxidation ditch treatments) had poor removal efficiency for linear PFASs (<21.4%) and branched isomers (<13.4%). No difference on removal efficiency among treatment processes was found. Furthermore, isomer composition in the WWTPs showed obvious differences between East China region and other regions, and the usage of short-chain PFASs (perfluorobutanesulfonic acid and perfluorohexanesulfonic acid) may be a key factor for driving this difference. This study sheds lights on the identification and characterization of PFAS isomers in WWTPs, which would be useful for development of monitoring and control strategies of PFASs.


Assuntos
Fluorcarbonetos , Poluentes Químicos da Água , Humanos , Poluentes Químicos da Água/análise , Fluorcarbonetos/química , China , Monitoramento Ambiental
5.
Org Biomol Chem ; 21(2): 300-305, 2023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36514892

RESUMO

Here, we developed an air-stable, earth-abundant cobalt(III)-catalyzed regioselective mono-olefination of arenes directed by urea under mild conditions through a cross-dehydrogenative coupling (CDC) process. Under the optimized conditions, a high regioselectivity of mono-olefination was achieved with various electron-rich and electron-deficient arenes, which afforded E-alkenylated products (with yields of up to 90%). In contrast to the conditions used for noble-metal-catalyzed olefination directed by weakly coordinating groups, our reaction was operated under mild conditions, including mild temperature (40 °C) and non-metallic oxidant.


Assuntos
Alcenos , Cobalto , Catálise , Estrutura Molecular , Oxidantes
6.
Environ Res ; 216(Pt 3): 114716, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36336092

RESUMO

Microplastics (MPs) have recently become an emerging environmental concern. Nevertheless, limited information is known about the adsorption of MPs for organic contaminants under combined heavy metals pollution, with an emphasis on the role of complexation. Thus, this study aims to comprehensively compare and investigate the adsorption performance of antibiotic tetracycline (TC) and ciprofloxacin (CIP) on two polar MPs (polyamide (PA) and polyvinyl chloride (PVC)) affected by Cu(II) and Cd(II) with contrasting complexation abilities. Batch adsorption experiments were used in combination with speciation calculation, zeta potential determination, FTIR spectroscopy characterization and investigation of the affinity of MPs for heavy metals. Results showed that the sorption kinetics and isotherms of TC and CIP on PA and PVC could be well fitted to pseudo-second-order and Langmuir models, respectively, both in the absence and presence of Cu and Cd, suggesting that multiple interactions and monolayer adsorption played an important role in the adsorption process. The presence of Cu substantially improved TC and CIP adsorption and obviously changed the pH dependence of their adsorption onto both MPs, which may result from the Cu-induced strong complexation with TC and CIP. The presence of Cd slightly enhanced TC adsorption on both MPs while reduced CIP adsorption especially on PVC, which may be ascribed to the Cd-induced cationic bridging effects in TC adsorption and the competitive adsorption of Cd in CIP adsorption. Therefore, the heavy metal-mediated complexation effects may play a dominant role in antibiotic adsorption by MPs only in the presence of heavy metals with strong complexation ability while the adsorption performance in the presence of heavy metals with negligible complexation capacity may be influenced by effects other than complexation. This study helps further understand the heavy metal-mediated adsorption behavior of organic contaminants on polar MPs and the role of complexation reactions therein.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Microplásticos , Adsorção , Ciprofloxacina/química , Plásticos , Antibacterianos , Cádmio , Cloreto de Polivinila , Metais Pesados/química , Tetraciclina/química , Poluentes Químicos da Água/análise
7.
Angew Chem Int Ed Engl ; : e202211741, 2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36583606

RESUMO

The nanoconfinement of proton carrier molecules may contribute to the lowing of their proton dissociation energy. However, the free proton transportation does not occur as easily as in liquid due to the restricted molecular motion from surface attraction. To resolve the puzzle, herein, imidazole is confined in the channels of porous coordination polymers with tunable geometries, and their electric/structural relaxations are quantified. Imidazole confined in a square-shape channels exhibits dynamics heterogeneity of core-shell-cylinder model. The core and shell layer possess faster and slower structural dynamics, respectively, when compared to the bulk imidazole. The dimensions and geometry of the nanochannels play an important role in both the shielding of the blocking effect from attractive surfaces and the frustration filling of the internal proton carrier molecules, ultimately contributing to the fast dynamics and enhanced proton conductivity.

8.
Nature ; 611(7935): 289-294, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36352136

RESUMO

The discovery of a method to separate isotopologues, molecular entities that differ in only isotopic composition1, is fundamentally and technologically essential but remains challenging2,3. Water isotopologues, which are very important in biological processes, industry, medical care, etc. are among the most difficult isotopologue pairs to separate because of their very similar physicochemical properties and chemical exchange equilibrium. Herein, we report efficient separation of water isotopologues at room temperature by constructing two porous coordination polymers (PCPs, or metal-organic frameworks) in which flip-flop molecular motions within the frameworks provide diffusion-regulatory functionality. Guest traffic is regulated by the local motions of dynamic gates on contracted pore apertures, thereby amplifying the slight differences in the diffusion rates of water isotopologues. Significant temperature-responsive adsorption occurs on both PCPs: H2O vapour is preferentially adsorbed into the PCPs, with substantially increased uptake compared to that of D2O vapour, facilitating kinetics-based vapour separation of H2O/HDO/D2O ternary mixtures with high H2O separation factors of around 210 at room temperature.

9.
Front Oncol ; 12: 1013790, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36419887

RESUMO

Transporter associated with antigen processing 1(TAP1) serves as a protein to transport antigenic peptides from the surface of the endoplasmic reticulum to the lumen of the endoplasmic reticulum when the antigens are presented by major histocompatibility complex type I (MHC-I), which has been identified to play a critical role in antigen presentation in innate immunity. In tumors, the role of TAP1 seems to remain controversial. On the one hand, given the role of TAP1 in antigen presentation, it is indicated that high TAP1 expression corresponds to the emergence of more neoantigens epitopes that facilitate the recognition for phagocytes, T cells and other cells. On the other hand, the genetic ablation of transporter associated with antigen processing (TAP) results in the presentation of new class I-restricted epitopes encoded in house-keeping products. Opposite result has been revealed by studies in other tumors suggest, which implies a more complex function of TAP1. Therefore, it's significant to clarify the role of TAP1 in clear cell renal cell carcinoma (ccRCC). In this study, we found the elevated expression levels in mRNA and protein of TAP1 in ccRCC tissues, which indicated a relatively worse prognosis. Transwell assay and Scratch assay in vitro demonstrated the promotive role of TAP1 in ccRCC migration as well as a significant role in metastasis. And the increased expression of TAP1 resulted in more immune cells infiltrated in cancer tissues. TAP1 was also demonstrated to be related to immune regulator genes, as gene set enrichment analysis (GSEA) indicated its significant role in immune regulation. The results of CancerSEA indicated the positive association of the high-level TAP1 expression with epithelial-mesenchymal transition (EMT) and the inverse association with Cell Cycle. The effective drugs were also predicted based on TAP1 expression, of which the high level was indeed associated with resistance to multiple drugs, but some effective drugs still identified based on high TAP1 expression. According to the analysis of various databases, the role of TAP1 in ccRCC was explored, especially in relationship of TAP1 with tumor microenvironment. These results indicate that TAP1 can serve as a potential target for treatment of ccRCC.

10.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 38(4): 317-321, 2022 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-36414554

RESUMO

Objective: To investigate the effects of 5-tetradecanoxy 2-furanic acid (TOFA) on cell proliferation, cell cycle and apoptosis of esophageal squamous cell carcinoma (ESCC) cells. Methods: Eca-109 cells and KYSE-450 cells were divided into control group (DMSO) and experimental group (TOFA), respectively. The cells (4×103 cells/100 µl) were inoculated into 96-well plates with 5 multiple wells at each concentration. After 24 h culture, cells were treated with DMSO or different concentrations (1, 3, 5, 10 µg/ ml) of TOFA for 24, 48 and 72 h. Cell proliferation was detected by MTT, cell cycle and apoptosis were detected by flow cytometry, the expression levels of p21 and Cleaved caspase-3 and modification levels of p-Akt, p-mTOR and p-4EBP1 were detected by Western blot, and intracellular free fatty acids were detected by special kits. Results: MTT results showed that TOFA inhibited the proliferation of Eca109 and KYSE-450 cells in a concentration and time dependent manner (all P<0.05), with IC50 of 4.65 µg/ml and 3.93 µg/ml for 48 h, respectively. Flow cytometry results showed that compared with DMSO group, the percentage of cells in G2/M phase was increased and the apoptosis rate was increased in the experimental group. Western blotting results showed that compared with DMSO group, p21 and Cleaved caspase-3 protein expression levels were up-regulated, and p-AKT, p-mTOR and p-4EBP1 protein expression levels were down-regulated (all P<0.05). Conclusion: TOFA inhibits the proliferation, blocks the cycle progression and promotes apoptosis of ESCC, the mechanism may be related to the AKT/mTOR/4EBP1 signaling pathway.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/metabolismo , Carcinoma de Células Escamosas do Esôfago/patologia , Caspase 3 , Neoplasias Esofágicas/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Dimetil Sulfóxido , Linhagem Celular Tumoral , Serina-Treonina Quinases TOR/metabolismo
11.
Environ Sci Technol ; 56(23): 17108-17118, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36399367

RESUMO

Limited information is available about prenatal exposure to per- and polyfluoroalkyl substances (PFAS) in electronic waste (e-waste) recycling sites. In this study, we determined 21 emerging PFAS and 13 legacy PFAS in 94 paired maternal and cord serum samples collected from an e-waste dismantling site in Southern China. We found 6:2 fluorotelomer sulfonate (6:2 FTSA), 6:2 chlorinated polyfluorinated ether sulfonate (6:2 Cl-PFESA), and perfluorooctanephosphonate (PFOPA) as the major emerging PFAS, regardless of matrices, at median concentrations of 2.40, 1.78, and 0.69 ng/mL, respectively, in maternal serum samples, and 2.30, 0.73, and 0.72 ng/mL, respectively, in cord serum samples. Our results provide evidence that e-waste dismantling activities contribute to human exposure to 6:2 FTSA, 6:2 Cl-PFESA, and PFOPA. The trans-placental transfer efficiencies of emerging PFAS (0.42-0.94) were higher than that of perfluorooctanesulfonic acid (0.37) and were structure-dependent. The substitution of fluorine with chlorine or hydrogen and/or hydrophilic functional groups may alter trans-placental transfer efficiencies. Multiple linear regression analysis indicated significant associations between maternal serum concentrations of emerging PFAS and maternal clinical parameters, especially liver function and erythrocyte-related biomarkers. This study provides new insights into prenatal exposure to multiple PFAS in e-waste dismantling areas and the prevalence of emerging PFAS in people living near the sites.


Assuntos
Ácidos Alcanossulfônicos , Resíduo Eletrônico , Fluorcarbonetos , Efeitos Tardios da Exposição Pré-Natal , Humanos , Feminino , Gravidez , Fluorcarbonetos/análise , Resíduo Eletrônico/análise , Placenta/química , Ácidos Alcanossulfônicos/análise , Éteres/análise , China
12.
Bull Environ Contam Toxicol ; 109(6): 1167-1174, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36331577

RESUMO

Novel visible-light-driven Ag3PO4/AgBr/AgI photocatalysts were prepared via a simple self-assembly strategy combined with in-situ anion-exchanging process. The photocatalytic activity of Ag3PO4 was significantly improved by constructing double-Z system. Specifically, the obtained materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and UV-vis diffuse reflectance spectroscopy (DRS). Under visible light irradiation (λ > 420 nm), the Ag3PO4/AgBr/AgI photocatalysts showed much higher photocatalytic activity than bulk Ag3PO4 for the degradation of formaldehyde (HCHO), and 100% HCHO degradation could be obtained within 28 min. The degradation efficiency could be maintained in five cycles. Further electron paramagnetic resonance (ESR) tests demonstrated that both •OH and •O2- generated in the system. This study provides new insights into the fabrication of highly efficient visible-light-driven photocatalysts and facilitates their practical application in emerging environment issues.

13.
Zhongguo Gu Shang ; 35(10): 962-6, 2022 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-36280413

RESUMO

The angle between the lower extremity force line and the position of the unicondylar prosthesis is an important factor affecting the long-term survival and rate clinical outcome of the unicondylar replacement prostheses. Insufficient lower limb alignment will accelerate the wear of prosthesis and reduce the survival rate of prosthesis. Excessive lower limb alignment will accelerate the progress of contralateral interventricular arthritis. It is generally believed that the lower limb force line should be corrected in mild varus after unicompartmental knee arthroplasty. However, some scholars believe that the lower limb alignment has no effect on the functional score and prosthesis survival rate after unicompartmental knee arthroplasty. The poor position of femoral and tibial prosthesis will cause unexplained pain and even prosthesis wear, but the optimal position of femoral and tibial prosthesis is controversial. It is generally believed that the posterior tibial slope should be corrected in the range of 3° to 7° in unicompartmental knee arthroplasty, but some scholars believe that excessive change of posterior tibial slope will also affect the balance of knee joint space and knee joint range of motion. This study shows that the correction of lower limb alignment to mild varus is still the best lower limb alignment for unicompartmental knee arthroplasty. The best position of femoral and tibial prosthesis needs to be confirmed by further biomechanical research. The correction of tposterior tibial slope should be changed according to the specific original dissection angle of patients before operation.


Assuntos
Artroplastia do Joelho , Prótese do Joelho , Osteoartrite do Joelho , Humanos , Articulação do Joelho/cirurgia , Tíbia/cirurgia , Osteoartrite do Joelho/cirurgia , Extremidade Inferior/cirurgia , Estudos Retrospectivos
14.
Nat Commun ; 13(1): 6125, 2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36253413

RESUMO

Phthalate esters (PAEs) have been extensively used as additives in plastics and wallcovering, causing severe environmental contamination and increasing public health concerns. Here, we find that hematite nanoparticles with specific facet-control can efficiently catalyze PAEs hydrolysis under ambient humidity conditions, with the hydrolysis rates 2 orders of magnitude higher than that in water saturated condition. The catalytic performance of hematite shows a significant facet-dependence with the reactivity in the order {012} > {104} ≫ {001}, related to the atomic array of surface undercoordinated Fe. The {012} and {104} facets with the proper neighboring Fe-Fe distance of 0.34-0.39 nm can bidentately coordinate with PAEs, and thus induce much stronger Lewis-acid catalysis. Our study may inspire the development of nanomaterials with appropriate surface atomic arrays, improves our understanding for the natural transformation of PAEs under low humidity environment, and provides a promising approach to remediate/purify the ambient air contaminated by PAEs.


Assuntos
Ésteres , Ácidos Ftálicos , China , Etilaminas , Compostos Férricos , Umidade , Hidrólise , Plásticos , Água
15.
Water Res ; 225: 119197, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36215839

RESUMO

Despite the extensive study of tetracycline photolysis in aquatic environments, the phototransformation of tetracycline and its metabolites under natural day-night succession has not been examined. In this study, we investigated tetracycline photolysis and associated ecotoxicity in two natural surface waters and one artificial ultrapure water under simulated day/night cycling over two days. Previously unrecognized and highly pH- and temperature-dependent dark interconversions of tetracycline metabolites were observed. The liquid chromatography-mass spectrometry/mass spectrometry analysis identified a range of isomerized, hydroxylated, demethylated, deaminated, and open-ring photoproducts. The hydrolysis of tetracycline, isotetracycline, and several intermediate products was proposed as the major mechanism for the observed dark transformations. Exposure studies employing Escherichia coli indicated that although the tetracycline degradation products had lower bacterial toxicities than the parent compound, increasing toxicity with irradiation time after the near-complete degradation of the parent compound in natural waters implied that product mixtures retain ecotoxicity. The dark transformations also affected the bacterial toxicity and fluorescence properties of irradiated tetracycline solutions. Overall, this study provides new insights into the photochemical behavior of tetracycline and its associated ecological risk in aquatic environments.


Assuntos
Poluentes Químicos da Água , Fotólise , Poluentes Químicos da Água/química , Tetraciclina/análise , Antibacterianos/química , Escherichia coli , Água , Cinética
16.
J Org Chem ; 87(21): 14241-14249, 2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36219805

RESUMO

By complementing traditional transition metal catalysis, photoinduced catalysis has emerged as a versatile and sustainable way to achieve carbon-heteroatom bond formation. This work discloses a visible-light-induced reaction for the formation of a C-S bond from aryl halides and inorganic sulfuration agents via electron donor-acceptor (EDA) complex photocatalysis. Divergent formations of organic sulfide and disulfide have been demonstrated under mild conditions. Preliminary mechanistic studies suggest that visible-light-induced intracomplex charge transfer within the monosulfide-anion-containing EDA complex permits the C-S bond construction reactivity.

17.
Water Res ; 225: 119147, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36206684

RESUMO

Per-/polyfluoroalkyl substances (PFASs) contamination has caused worldwide health concerns, and increased demand for effective elimination strategies. Herein, we developed a new indole derivative decorated with a hexadecane chain and a tertiary amine center (named di-indole hexadecyl ammonium, DIHA), which can form stable nanospheres (100-200 nm) in water via supramolecular assembly. As the DIHA nanospheres can induce electrostatic, hydrophobic and van der Waals interactions (all are long-ranged) that operative cooperatively, in addition to the nano-sized particles with large surface area, the DIHA nanocomposite exhibited extremely fast adsorption rates (in seconds), high adsorption capacities (0.764-0.857 g g-1) and selective adsorption for perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), outperformed the previous reported high-end PFASs adsorbents. Simultaneously, the DIHA nanospheres can produce hydrated electron (eaq-) when subjected to UV irradiation, with the virtue of constraining the photo-generated eaq- and the adsorbed PFOA/PFOS molecules entirely inside the nanocomposite. As such, the UV/DIHA system exhibits extremely high degradation/defluorination efficiency for PFOA/PFOS, even under ambient conditions, especially with the advantages of low chemical dosage requirement (µM level) and robust performance against environmental variables. Therefore, it is a new attempt of using supramolecular approach to construct an indole-based nanocomposite, which can elegantly combine adsorption and degradation functions. The novel DIHA nanoemulsion system would shed light on the treatment of PFAS-contaminated wastewater.


Assuntos
Ácidos Alcanossulfônicos , Compostos de Amônio , Fluorcarbonetos , Poluentes Químicos da Água , Fluorcarbonetos/química , Adsorção , Poluentes Químicos da Água/análise , Ácidos Alcanossulfônicos/química , Caprilatos/química , Água , Indóis , Aminas
18.
Artigo em Inglês | MEDLINE | ID: mdl-36242096

RESUMO

Aims: Radiation by-radiation effect (RIBE) can induce the genomic instability of bone marrow mesenchymal stem cells (BMSCs) adjacent to lung cancer, and this effect not only exists in the short-term, but also accompanies it in the long-term, but its specific mechanism is not clear. Our goal is to explore the similarities and differences in the mechanism of genomic damage in tumor-associated BMSCs induced by short-term and long-term RIBE, and to provide a theoretical basis for adjuvant drugs for protection against RIBE at different clinical time periods. Results: We found that both short- and long-term RIBE induced genomic instability. We could show a high expression of TGF-ß1, TNF-α, and HIF-1α in tumor-associated BMSCs after short-term RIBE whereas only TNF-α and HIF-1α expression was increased in long-term RIBE. We further confirmed that genomic instability is associated with the activation of the HIF-1α pathway and that this is mediated by TNF-α and TGF-ß1. In addition, we found differences in the mechanisms of genomic instability in the considered RIBE windows of analysis. In short-term RIBE, both TNF-α and TGF-ß1 play a role, whereas only TNF-α plays a decisive role in long-term RIBE. In addition, there were differences in BMSC recruitment and genomic instability of different tissues with a more pronounced expression in tumor and bone marrow than compared to lung. Innovation and Conclusion: We could show dynamic changes in the expression of the cytokines TGF-ß1 and TNF-α during short- and long-term RIBE. The differential expression of the two is the key to causing the genomic damage of tumor-associated BMSCs in the considered windows of analysis. Therefore, these results may serve as a guideline for the administration of radiation protection adjuvant drugs at different clinical stages.

19.
J Am Chem Soc ; 144(40): 18218-18222, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36069433

RESUMO

We report a multi-component synthetic strategy on a two-dimensional crystalline covalent organic framework (COF) by connecting acetonitrile with aromatic aldehyde and acetaldehyde moieties to form an unprecedented cyano-substituted buta-1,3-diene linkage. Different from most of the COFs that were crystallized from the condensations from two components, the presented COF is generated from two competitive and reversible reactions among three moieties. The buta-1,3-diene COF exhibits remarkable photoactivity with a low exciton binding energy of 44.4 ± 1.5 meV for promoted charge separation, which enables the buta-1,3-diene-linked COF as an efficient photocatalyst for various aerobic oxidation reactions under visible light. Our multi-component synthesis strategy may provide new sights for synthesizing COFs with structural diversity and functional variability that are hard to achieve by traditional COF synthesis.

20.
Macromol Rapid Commun ; : e2200678, 2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36069655

RESUMO

The development and understanding of proton conductors based on phosphoric acid are critical for the field of chemistry, biology, and energy. Covalent organic frameworks (COFs), featuring highly crystalline structures and controllable pore sizes, are suitable for constructing phosphoric acid-based proton conductors. However, because of tedious and intricate synthesis, how to develop COFs based on phosphoric acid remains a substantial challenge. Herein, a side-chain decorated strategy is contributed to construct a phosphoric acid-functionalized, imine-linked COF by de novo synthesis. The phosphoric acid side chains with vigorous motion integrating with 1D nanochannels endow the resulting COF with intrinsic proton conductivity. This work expectantly provides a competitive alternative for producing phosphoric acid-functionalized COFs with high intrinsic proton conductivity.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...