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1.
Environ Pollut ; 292(Pt A): 118325, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34634408

RESUMO

Lead (Pb) is a toxic metal in industrial production, which can seriously threat to human health and food safety. Thus, it is particularly crucial to reduce the content of Pb in the environment. In this study, raw fly ash (FA) was used to synthesise a new active silicate materials (IM) employing the low-temperature-assisted alkali (NaOH) roasting approach. The IM was further synthesised to form zeolite-A (ZA) using the hydrothermal method. The physicochemical characteristics of IM and ZA amendments before and after Pb2+ adsorption were analysed using the Scanning electron microscope-Energy Dispersive Spectrometer (SEM-EDS), Fourier Transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) apparatuses. The results revealed the considerably change in the microstructure and functional groups of IM and ZA amendments, conducive to Pb2+ removal. Moreover, a 3-year field experiment revealed that the IM and ZA significantly improved the growth of rice and reduced available Pb by 21%-26.8% and 9.7%-16.9%, respectively. After 3 years of remediation, the Pb concentration of the rice grain reached the national edible standard (≤0.2 mg kg-1) of 0.171 mg kg-1 and 0.179 mg kg-1, respectively. Meanwhile, the concentration of acid-exchangeable Pb reduced, while those of reducible and residual fractions of Pb increased. There was no significant difference between the IM and ZA treatments. The potential mechanisms of remediation by the amendments were ion-exchange, complexation, precipitation, and electrostatic attraction. Overall, the results indicate that IM is suitable for the remediation of contaminated soil and promotes safe food production, and develops an environmentally friendly and cost-effective amendment for the remediation of polluted soil.


Assuntos
Oryza , Poluentes do Solo , Cádmio/análise , Humanos , Silicatos , Solo , Poluentes do Solo/análise
2.
Org Lett ; 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34730361

RESUMO

A base-catalyzed double annulation of isocyanoacetates with various enynones has been developed for the expeditious synthesis of 4-azafluorene and 4-azafluorenone derivatives. Against the well-known 1,3-dipolar reactivities, the active methylene and isocyano groups of isocyanoacetate serve as nucleophiles in this domino transformation.

3.
Chem Sci ; 12(41): 13817-13824, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34760167

RESUMO

Spatiotemporally activatable immune cells are promising for tumor immunotherapy owing to their potential high specificity and low side effects. Herein, we developed an X-ray-induced phenotypic transformation (X-PT) strategy through macrophage engineering for safe and efficient tumor immunotherapy. Without complex genetic engineering, the cell membranes of M0-type macrophages were chemically engineered with AS1411 aptamer-based polyvalent spherical aptamer (PSA) via the combination of metabolic glycan labelling and bioorthogonal click reaction. Owing to the superior specificity, affinity and polyvalent binding effects of the high-density AS1411 aptamers, the engineered macrophages could easily recognize and adhere to tumor cells. With further X-ray irradiation, reactive oxygen species (ROS) generated by the Au-based PSA could efficiently transform the accumulated macrophages in situ from biocompatible M0 into antitumoral M1 phenotype via activating the nuclear factor κB signaling pathway, thereby achieving tumor-specific killing. In vitro and in vivo experiments confirmed the high tumor recognition and X-ray-induced polarization effect of the engineered macrophages. Compared to natural macrophages, our engineered macrophages significantly inhibited tumor growth in mice even if the radiation dose was reduced by three-fold. We believe this X-PT strategy will open a new avenue for clinical immune cell-based therapy.

4.
Acta Pharm Sin B ; 11(10): 3165-3177, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34729307

RESUMO

mediated cancer therapy has achieved remarkable anti-tumor effects in experimental animal models, but the detailed mechanism remains unsolved. In this report, the active involvement of the host immune response in this process was confirmed by comparing the tumor-suppressive effects of Salmonella in immunocompetent and immunodeficient mice bearing melanoma allografts. Since flagella are key inducers of the host immune response during bacterial infection, flagella were genetically disrupted to analyse their involvement in Salmonella-mediated cancer therapy. The results showed that flagellum-deficient strains failed to induce significant anti-tumor effects, even when more bacteria were administered to offset the difference in invasion efficiency. Flagella mainly activate immune cells via Flagellin/Toll-like receptor 5 (TLR5) signalling pathway. Indeed, we showed that exogenous activation of TLR5 signalling by recombinant Flagellin and exogenous expression of TLR5 both enhanced the therapeutic efficacy of flagellum-deficient Salmonella against melanoma. Our study highlighted the therapeutic value of the interaction between Salmonella and the host immune response through Flagellin/TLR5 signalling pathway during Salmonella-mediated cancer therapy, thereby suggesting the potential application of TLR5 agonists in the cancer immune therapy.

5.
Pharmacol Res ; : 105992, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34801681

RESUMO

BACKGROUND: Recent evidence suggests that neuropsychiatric stabilizers have a place in resolving gastrointestinal disorders. Lithium carbonate (LC) is one of the most commonly used drugs for bipolar disorder clinically. Here, we estimate the therapeutic function of LC against colitis and investigate the mechanism of intestinal flora and metabolism modulation. METHODS: A colitis model was constructed by continuously administering 2.5% dextran sodium sulfate (DSS) solution daily for 7 days. Analysis of gut microbiota was carried out by 16S rRNA gene high-throughput sequencing. Spectrum antibiotic cocktail (ABX) and faecal microbiota transplantation (FMT) were employed to evaluate the protective effect of intestinal flora. Colonic Treg cells and related immune responses were detected by flow cytometry. RESULTS: LC treatment significantly alleviated colon inflammation by regulating gut microbial diversity and altering flora composition. Notably, LC treatment upregulated short-chain fatty acid (SCFA)-producing bacteria, especially Akkermansia muciniphila (A. muciniphila), and transformed metabolite SCFA profiles. LC activated anti-inflammatory Treg cell responses in colonic LP in a G-protein coupled receptor 43 (GPR43)-dependent mechanism. ABX, FMT and single bacteria gavage experiments were conducted to confirm the above mechanism. CONCLUSIONS: As an intestinal microbiome and metabolite modulator, LC alleviates colon inflammation in a GPR43-dependent manner through activating Treg cell responses. Therefore, the therapeutic strategy of the microbiome-metabolite-immune axis, as observed in the A. muciniphila-SCFA-Treg cell axis in our study, might provide a new direction for the treatment of IBD.

6.
Anal Chem ; 93(45): 15088-15095, 2021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34729977

RESUMO

Alzheimer's disease (AD) involves multiple pathological factors that mutually cooperate and closely contact to form interaction networks for jointly promoting the AD progression. Therefore, the comonitoring of different factors is particularly valuable for elucidating their level dynamics and complex interactions. However, such significant investigations remain a major challenge due to the lack of unimolecular fluorescent probes capable of simultaneous and discriminative visualization of multiple targets. To address this concern, as proof of principle, we rationally designed a unimolecular fluorescent probe to discriminate and simultaneously profile amyloid-ß (Aß) plaques and peroxynitrite (ONOO-), which are both the pronounced AD pathological factors. Herein, a novel ONOO- reaction trigger was installed onto an Aß plaque binding fluorophore to generate a dual functional fluorescent probe, displaying completely separate spectral responses to Aß plaques and ONOO- with high selectivity and sensitivity. With this probe, for the first time, we comonitored the distribution and variation of Aß plaques and ONOO- through two independent fluorescence channels, demonstrating their close apposition and tight correlation during AD course in live cell and mouse models through two-photon imaging mode. Notably, Aß aggregates induce the neuronal ONOO- generation, which conversely facilitates Aß aggregation. The two critical events, ONOO- stress and Aß aggregation, mutually amplify each other through positive feedback mechanisms and jointly promote the AD onset and progression. Furthermore, by coimaging of the level dynamics of Aß plaques and ONOO-, we found that the cerebral ONOO- is a potential biomarker, which emerges earlier than Aß plaques in transgenic mouse models. Overall, the dual-channel responsive performance renders this probe as a powerful imaging tool to decipher Aß plaque-ONOO- interactions, which will facilitate AD-associated molecular pathogenesis elucidation and multitarget drug discovery.


Assuntos
Doença de Alzheimer , Doença de Alzheimer/diagnóstico por imagem , Peptídeos beta-Amiloides , Animais , Corantes Fluorescentes , Camundongos , Camundongos Transgênicos , Ácido Peroxinitroso , Placa Amiloide/diagnóstico por imagem
7.
Anal Chem ; 93(45): 15216-15223, 2021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34736322

RESUMO

The development of a sensitive, facile, and cost-effective colorimetric method is of great significance for the point-of-care testing of viral nucleic acid. Herein, we reported a strand displacement amplification assisted CRISPR-Cas12a (SDACC) method for the colorimetric analysis of viral nucleic acid. The hepatitis B virus (HBV) DNA was chosen as the target to trigger strand displacement amplification (SDA) and generate abundant single-strand DNA (ssDNA) products. The ssDNA amplicon hybridized with template DNA to activate the trans-cleavage activity of CRISPR-Cas12a, leading to the nonspecific cleavage of ssDNA on GOx-ssDNA-modified magnetic beads and the release of GOx. The released GOx was capable of catalyzing the substrate solution to generate a color change, which could be directly observed by naked eyes. The SDACC strategy could identify a single-base mismatch located in the DNA sequence and achieve a sensitive detection for HBV DNA with the limit of detection as low as 41.8 fM. Notably, the sophisticated primer design for target amplification and complicated detection process could be circumvented. The current approach realizes a simple, low-cost, and sensitive colorimetric detection for viral nucleic acid and holds great promise for the practical application of virus infection diagnosis.


Assuntos
Técnicas Biossensoriais , Ácidos Nucleicos , Sistemas CRISPR-Cas/genética , Colorimetria , DNA , DNA de Cadeia Simples/genética , Técnicas de Amplificação de Ácido Nucleico
8.
Anal Chem ; 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34802229

RESUMO

Tumor microenvironment (TME) is the survival environment for tumor cells to proliferate and metastasize in deep tissue. TME contains tumor cells, immune cells, stromal cells and a variety of active molecules including reactive oxygen species (ROS). Inside the TME, ROS regulate the oxidation-reduction (redox) homeostasis and promote oxidative stress. Due to the rapid proliferation ability and specific metabolic patterns of the TME, ROS pervade virtually all complex physiological processes and play irreplaceable roles in protein modification, signal transduction, metabolism, and energy production in various tumors. Therefore, measurements of the dynamically, multicomponent simultaneous changes of ROS in the TME are of great significance to reveal the detailed proliferation and metastasis mechanisms of the tumor. Near-infrared (NIR) and two-photon (TP) fluorescence imaging techniques possess real-time, dynamic, highly sensitive, and highly signal-to-noise ratios with deep tissue penetration abilities. With the rationally designed probes, the NIR and TP fluorescence imaging techniques have been widely used to reveal the mechanisms of how ROS regulates and constructs complex signals and metabolic networks in TME. Therefore, we summarize the design principles and performances of NIR and TP fluorescence imaging of ROS in the TME in the last four years, as well as discuss the advantages and potentials of these works. This Review can provide guidance and prospects for future research work on TME and facilitate the development of antitumor drugs.

9.
Chem Commun (Camb) ; 57(94): 12619-12622, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34757362

RESUMO

Four novel two-dimensional porphyrin COFs (M-TP-COF, M = H2, Co, Ni and Mn) with donor-acceptor dyads were fabricated and served as electrocatalysts for the oxygen reduction reaction (ORR). The ORR catalytic activity of M-TP-COF was tuned by changing the M atom in the center of the porphyrin backbone. The experimental structure-function relationship was in accordance with the results of density functional theory calculations based on the O2-O2*-OOH*-O*-OH*-OH- route.

10.
Chem Commun (Camb) ; 57(94): 12679-12682, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34779461

RESUMO

By means of the formation of SeN, the ABT-Se and NDI-Se were developed to detect and visualize endogenous hypobromous acid (HOBr) in live cells. Specifically, the upregulation of HOBr was monitored by NDI-Se during the administration of an immunotherapeutic agent.

11.
Artigo em Inglês | MEDLINE | ID: mdl-34811855

RESUMO

In chemodynamic therapy (CDT), the levels of reactive oxygen species (ROS) production plays an important role for evaluating the therapeutic efficacy. However, the high levels of glutathione (GSH) in tumor cells consume the ROS, directly reducing the therapeutic efficiency. Herein, we synthesized carbon-based nanoparticle (Cu-cys CBNPs) using one-pot strategy, which consume GSH via redox reactions to produce Cu+ that catalyze H2O2 to produce ·OH, thus the ROS level was observably increased through this synergistic effect. In vivo experiments further revealed that Cu-cys CBNPs could effectively inhibit tumor growth. Additionally, Cu-cys CBNPs can affect the activity of some protein sulfhydryl groups in cells, which was assessed by rdTOP-ABPP assay. In general, this study not only provides a potential CDT drug, but also provides a strategy for one-pot synthesis of multifunctional nanomaterials.

12.
Chem Commun (Camb) ; 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34812448

RESUMO

We report here a catalytically active nano covalent organic framework [COF(Fe)] with high drug loading capacity for reversing tumor multidrug resistance (MDR). The Fe catalytic sites in COF(Fe) could convert intracellular overexpressed H2O2 into highly reactive ˙OH to induce oxidation stress and down-regulate MDR protein. Therefore, COF(Fe) could enhance the intracellular drug accumulation to overcome MDR, which was demonstrated both in vitro and in vivo.

13.
Chem Commun (Camb) ; 2021 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-34842863

RESUMO

Electrocatalytic NO reduction controls NO emission and produces NH3 under ambient conditions. Herein, a NiO nanosheet array on titanium mesh is proposed as a highly active and selective electrocatalyst for NO reduction, attaining a faradaic efficiency of up to 90% with a NH3 yield of 2130 µg h-1 cm-2. Its aqueous Zn-NO battery can generate electricity with a power density of 0.88 mW cm-2 and simultaneously offer an NH3 yield of 228 µg h-1 cm-2. The NO electroreduction mechanism on NiO is revealed using theoretical calculations.

14.
Chem Commun (Camb) ; 57(92): 12301-12304, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34730575

RESUMO

Herein, we developed a triple-line lateral flow strip-based platform combined with an miRNA-initiated cyclic chain displacement reaction for the rapid and simultaneous dual-miRNA detection of lung cancer in a single strip test. The simultaneous dual-miRNA detection platform was used for the analysis of clinical serum samples, and distinguished non-small cell lung cancer patients from heathy individuals.

15.
Ann Vasc Surg ; 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34780965

RESUMO

OBJECTIVE: For treatment of infected femoral artery pseudoaneurysms (IFAPs) with the covered stent, debridement technique is important but frequently ignored. Our study aims to review our experience and outcomes of patients undergoing covered stents placement and debridement with vacuum sealing drainage (VSD). METHODS: This study retrospectively analyzed 41 intravenous drug addicts with IFAP who received covered stent implantation and debridement with VSD from January 2015 to December 2020. The diagnosis was based on the previous history of local injection and the presence of pulsatile mass at the injection site. All cases were confirmed by CT angiography (CTA), ultrasound, or digital subtraction angiography (DSA). Technical success, time of wound care, and clinical outcomes were evaluated. RESULTS: Technical success was achieved in all patients. The interval from diagnosis to treatment was 26 ± 11 hours. The time of continuous drainage with VSD was 18.79 ± 6.56 days. 38 patients (92.68%) with fresh granulation tissue were sutured and discharged from the hospital. Stents in 31(91.18%) of 34 cases were patent during follow-ups. Three patients had stent occlusion caused by thrombosis, and two of them were complicated with stent infection. The two infectious stents were removed and the femoral arteries were ligated. One of them received open-surgical reconstruction with the great saphenous because of claudication. Two patients were admitted to the hospital for rebleeding caused by drug abuse relapse. CONCLUSION: Covered stents placement is convenient and rapid to control massive hemorrhage in IFAPs of intravenous drug abuse. Early debridement of infected tissue with continued VSD may shorten the time of wound care and make the incidence of stent infection relatively low. Meanwhile, the patency in a short time follow-up is acceptable. These results indicates that covered stents implantation with VSD may be a safe, effective, and feasible measure for the treatment of IFAPs.

16.
Chem Commun (Camb) ; 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34807209

RESUMO

In this study, porous hierarchical bronze/anatase phase junction TiO2 assembled by ultrathin two-dimensional nanosheets was prepared by a novel, green and simple deep eutectic solvent-regulated strategy. Due to its structural features, the TiO2 sample exhibited enhanced photocatalytic activities for multiple kinds of antibiotics, including ofloxacin, ciprofloxacin and chloramphenicol.

17.
J Hazard Mater ; 424(Pt C): 127592, 2021 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-34736216

RESUMO

Acrylamide (AA) is now recognized as an imminent hazardous chemical in the aqueous environment, causing a potential threat to human health. As a neo-formed contaminant (NFC), the degradation measure of AA is largely lacking. In this work, we used quantum chemistry and experimental methods to identify the main degradation mechanism of AA in the UV/H2O2 advanced oxidation process (AOP) for the first time. Radical addition reactions dominate the •OH-initiated AA reaction, resulting in few toxic nitrosamines formation. The interaction between AA and the surface model of soil particles (SixOy(OH)z) is weak, and AA can rapidly migrate down to groundwater via seepage. However, the total rate constants of AA and COMADS2-AA with •OH are 2.75 × 109 and 2.09 × 109 M-1 s-1, and the removal of AA from aqueous and heterogeneous systems reaches 62.30% and 62.05% within 2 h. Whether in the aqueous-phase or on the surface of soil particles, •OH initiated AA reaction is an efficient way to remove AA. Furthermore, the toxicity of the main by-products of AA show less harmful to three aquatic organisms and rats than AA. UV/H2O2 AOP is evaluated as an efficient method to degrade AA while decreasing harm.

18.
Anal Chem ; 93(40): 13734-13741, 2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34605236

RESUMO

Precisely detecting biomarkers in living systems holds tremendous promise for disease diagnosis and monitoring. Herein, we developed a covalent organic framework (COF)-based tricolor fluorescent nanoprobe for simultaneously imaging biomarkers with different spatial locations in living cells. Briefly, a TAMRA-labeled survivin mRNA antisense nucleotide and a Cy5-labeled transmembrane glycoprotein mucin 1 (MUC1) aptamer were adsorbed on a nanoscale fluorescent COF. To enhance the interactions between COF nanoparticles (NPs) and nucleic acid molecules, a freezing method was employed for improving the nucleic acid loading density and ensuring detection performance. The fluorescence signals of dyes on DNAs were first quenched by the COF NPs. Internalization and distribution of the nanoprobes can be real-time visualized by the autofluorescence of COF NPs. In living cells, recognition between MUC1 with MUC1 aptamers causes fluorescence signal recovery of Cy5, while hybridization between survivin mRNA and its antisense DNA induces the signal recovery of TAMRA. Therefore, this COF-based multicolor nanoprobe could be employed for visualizing MUC1 on the cell membrane and survivin mRNA in the cytoplasm. Cancer cell-specific diagnostic imaging and monitoring of the process of cancer cell exosomes infecting normal cells using the nanoprobe were achieved. This work not only offers a versatile nanoprobe for bioanalysis but also provides new insights for developing novel COF-based nanoprobes.


Assuntos
Estruturas Metalorgânicas , Nanopartículas , Ácidos Nucleicos , DNA , Corantes Fluorescentes , Imagem Óptica
19.
Eur J Med Res ; 26(1): 124, 2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34666837

RESUMO

BACKGROUND: Talus osteochondral lesion is commonly associated with trauma, avascular necrosis or even genetic factors, but gouty tophus as a cause of Hepple stage V type talus osteochondral lesion is rare. CASE PRESENTATION: Here, we report a case of an 18-year-old man who complained of left medial deep ankle pain on ambulation. This young man had an extreme liking of sea food rich in purines and also sugar-sweetened drinks. He was diagnosed with a Hepple stage V type talus osteochondral lesion and was treated with medial malleolus osteotomy and an osteochondral graft. The talus osteochondral lesion was found to be a gouty tophus and was completely removed. Hypouricemic therapy was prescribed for 2 months, which allowed the patient to walk with a visual analogue score (VAS) score of 1. He was followed up for 12 months. CONCLUSIONS: Young people with an extreme liking of sea food rich in purines and also sugar-sweetened drinks may be at a risk of developing gout. Acute onset of ankle atraumatic pain, swelling with a high level of serum uric acid and a talus osteochondral lesion with cyst formation should make physicians consider a diagnosis of gout.

20.
J Immunol Res ; 2021: 8727924, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34692853

RESUMO

Background: The CXC chemokines belong to a unique family of cytokines that participates in the progression and development of many malignant tumors. Evidence for the relationship between chemokine (C-X-C motif) receptor 2 (CXCR2) C1208T polymorphism and susceptibility to cancer remains inconsistent. Methods: Odds ratios (ORs), 95% confidence intervals (CIs), and combined analysis were used to investigate the effect of CXCR2 variation on cancer risk. Gene Set Enrichment Analysis (GSEA) and enzyme-linked immunosorbent assay (ELISA) were also used to evaluate the expression of CXCR2 in prostate cancer (PCA). Results: Across 11 case-control studies, 4,909 cases and 5,884 controls were involved in the current analysis. Individuals with a TT genotype were associated with increased risk of digestive cancer, compared to those with a TC+CC genotype (OR = 1.16, 95%CI = 1.02-1.31, P = 0.025). Individuals carrying the TT genotype had a 39% higher risk of urinary cancer than those carrying CC genotype (OR = 1.39, 95%CI = 1.04-1.87, P = 0.025). Individuals with a TT genotype showed a 56% augmented breast cancer risk, compared to those with a CC genotype (OR = 1.56, 95%CI = 1.03-2.35, P = 0.034). It was found that CXCR2 expression was downregulated in PCA. Compared with PCA subjects carrying the CC genotype, the expression of CXCR2 was decreased in patients with the TT genotype. Conclusions: The CXCR2 C1208T variation was associated with elevated risk of urinary, breast, and digestive cancer. However, the C1208T polymorphism was correlated with attenuated risk of lung cancer.

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