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1.
World J Gastrointest Endosc ; 16(2): 72-82, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38464816

RESUMO

BACKGROUND: Endoscopic submucosal dissection (ESD) and surgical resection are the standard of care for cT1N0M0 esophageal cancer (EC), whereas definitive chemoradiotherapy (d-CRT) is a treatment option. Nevertheless, the comparative efficiency and safety of ESD, surgery and d-CRT for cT1N0M0 EC remain unclear. AIM: To compare the efficiency and safety of ESD, surgery and d-CRT for cT1N0M0 EC. METHODS: We retrospectively analyzed the hospitalized data of a total of 472 consecutive patients with cT1N0M0 EC treated at Sun Yat-sen University Cancer center between 2017-2019 and followed up until October 30th, 2022. We analyzed demographic, medical recorded, histopathologic characteristics, imaging and endoscopic, and follow-up data. The Kaplan-Meier method and Cox proportional hazards modeling were used to analyze the difference of survival outcome by treatments. Inverse probability of treatment weighting (IPTW) was used to minimize potential confounding factors. RESULTS: We retrospectively analyzed patients who underwent ESD (n = 99) or surgery (n = 220) or d-CRT (n = 16) at the Sun Yat-sen University Cancer Center from 2017 to 2019. The median follow-up time for the ESD group, the surgery group, and the d-CRT group was 42.0 mo (95%CI: 35.0-60.2), 45.0 mo (95%CI: 34.0-61.75) and 32.5 mo (95%CI: 28.3-40.0), respectively. After adjusting for background factors using IPTW, the highest 3-year overall survival (OS) rate and 3-year recurrence-free survival (RFS) rate were observed in the ESD group (3-year OS: 99.7% and 94.7% and 79.1%; and 3-year RFS: 98.3%, 87.4% and 79.1%, in the ESD, surgical, and d-CRT groups, respectively). There was no difference of severe complications occurring between the three groups (P ≥ 0.05). Multivariate analysis showed that treatment method, histology and depth of infiltration were independently associated with OS and RFS. CONCLUSION: For cT1N0M0 EC, ESD had better long-term survival and lower hospitalization costs than those who underwent d-CRT and surgery, with a similar rate of severe complications occurring.

2.
Angew Chem Int Ed Engl ; : e202402760, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483296

RESUMO

The phenomenon of polymorphism is ubiquitous in nature, the controlled manipulation of which not only increases our ontological understanding of nature but also facilitates the conceptualization and realization of novel functional materials. However, achieving targeted polymorphism in supramolecular assemblies (SAs) remains a formidable challenge, largely because of the constraints inherent in controlling the specific binding motifs of noncovalent interactions. Herein, we propose self-adaptive aromatic cation-π binding motifs to construct polymorphic SAs in both the solid and solution states. Using distinct discrete cation-π-cation and long-range cation-π binding motifs enables control of the self-assembly directionality of a C2h-symmetric bifunctional monomer, resulting in the successful formation of both two-dimensional and three-dimensional crystalline SAs (2D-CSA and 3D-CSA). The differences in the molecular packing of 3D-CSA compared with that of 2D-CSA significantly improve the charge separation and carrier mobility, leading to enhanced photocatalytic activity for the aerobic oxidation of thioanisole to methyl phenyl sulfoxide (yield of 99 % vs 57 %). 2D-CSA, which has a vertical extended structure with favorable stronger interaction with toluene though face-to-face cation-π interactions than methylcyclohexane, shows higher toluene/methylcyclohexane separation efficiency than 3D-CSA (96.9 % for 2D-CSA vs 56.3 % for 3D-CSA).

3.
Sci Total Environ ; 925: 171785, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38508244

RESUMO

Per- and polyfluoroalkyl substances (PFASs) have garnered considerable scientific and regulatory scrutiny due to their widespread distribution across environments and their potential toxicological impacts on human health. The pedosphere serves as a vital reservoir for these chemicals, significantly determining their environmental trajectory and chemical transformations. This study offers a comprehensive synthesis of the current understanding regarding the adsorption mechanics of PFASs in soil matrices. Due to their unique molecular structure, PFASs predominantly engage in hydrophobic and electrostatic interactions during soil adsorption. This work thoroughly evaluates the influence of various factors on adsorption efficiency, including soil properties, molecular characteristics of PFASs, and the prevailing environmental conditions. The complex nature of soil environments complicates isolating individual impacts on PFAS behavior, necessitating an integrated approach to understanding their environmental destinies better. Through this exploration, we seek to clarify the complex interplay of factors that modulate the adsorption of PFASs in soils, highlighting the urgent need for future research to disentangle the intricate and combined effects that control the environmental behavior of PFAS compounds.


Assuntos
Fluorocarbonos , Poluentes Químicos da Água , Humanos , Solo/química , Poluentes Químicos da Água/análise , Adsorção , Fluorocarbonos/análise , Estrutura Molecular
4.
J Hazard Mater ; 469: 133817, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38422730

RESUMO

The soil near tailings areas is relatively barren and contaminated by multi-metal(loid)s, seriously threatening the safety of crop production. Here, biochar and nano-hydroxyapatite (nHAP) were combined to improve the sterilized and unsterilized polymetallic contaminated soil, and soil incubation and soybean pot experiments were designed. Results showed that biochar and nHAP not only increased soil C, N, and P but also effectively reduced multi-metal bioavailability, wherein the combined application of the two amendments had the best effect on metal immobilization. The synergistic effect of the two amendments decreased the acid-soluble contents of Co, Cu, Fe, and Pb in rhizosphere soils up to 86.75%, 80.69%, 89.09%, and 96.70%, respectively. The ameliorant reduced the accumulation of metal(loid)s in soybean plants, and rhizosphere microorganisms inhibited the migration of soil metals to plants. Additionally, biochar and nHAP regulated the rhizosphere soil microbial community. The rhizosphere soil of the sterilization group tended to prioritize the restoration of the original dominant bacteria. As, Pb, Fe, Urease, OM, TN, and TP were the critical environmental variables affecting rhizosphere soil bacterial communities. Therefore, combining biochar and nHAP is an environmentally friendly strategy to reduce polymetallic mobility in tailings soil and crops and improve soil microbial community structure.


Assuntos
Pirenos , Poluentes do Solo , Solo , Solo/química , Soja , Durapatita/química , Rizosfera , Microbiologia do Solo , Chumbo , Carvão Vegetal/química , Poluentes do Solo/análise
5.
Nat Commun ; 15(1): 1438, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38365793

RESUMO

The Tibetan Plateau supplies water to nearly 2 billion people in Asia, but climate change poses threats to its aquatic microbial resources. Here, we construct the Tibetan Plateau Microbial Catalog by sequencing 498 metagenomes from six water ecosystems (saline lakes, freshwater lakes, rivers, hot springs, wetlands and glaciers). Our catalog expands knowledge of regional genomic diversity by presenting 32,355 metagenome-assembled genomes that de-replicated into 10,723 representative genome-based species, of which 88% were unannotated. The catalog contains nearly 300 million non-redundant gene clusters, of which 15% novel, and 73,864 biosynthetic gene clusters, of which 50% novel, thus expanding known functional diversity. Using these data, we investigate the Tibetan Plateau aquatic microbiome's biogeography along a distance of 2,500 km and >5 km in altitude. Microbial compositional similarity and the shared gene count with the Tibetan Plateau microbiome decline along with distance and altitude difference, suggesting a dispersal pattern. The Tibetan Plateau Microbial Catalog stands as a substantial repository for high-altitude aquatic microbiome resources, providing potential for discovering novel lineages and functions, and bridging knowledge gaps in microbiome biogeography.


Assuntos
Microbiota , Humanos , Tibet , Microbiota/genética , Lagos , Rios , Água
7.
Int J Biol Macromol ; 256(Pt 2): 128513, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38040159

RESUMO

Nano drug delivery systems offer several benefits, including enhancing drug solubility, regulating drug release, prolonging drug circulation time, and minimized toxicity and side effects. However, upon entering the bloodstream, nanoparticles (NPs) encounter a complex biological environment and get absorbed by various biological components, primarily proteins, leading to the formation of a 'Protein Corona'. The formation of the protein corona is affected by the characteristics of NPs, the physiological environment, and experimental design, which in turn affects of the immunotoxicity, specific recognition, cell uptake, and drug release of NPs. To improve the abundance of a specific protein on NPs, researchers have explored pre-coating, modifying, or wrapping NPs with the cell membrane to reduce protein adsorption. This paper, we have reviewed studies of the protein corona in recent years, summarized the formation and detection methods of the protein corona, the effect of the protein corona composition on the fate of NPs, and the design of new drug delivery systems based on the optimization of protein corona to provide a reference for further study of the protein corona and a theoretical basis for the clinical transformation of NPs.


Assuntos
Nanopartículas , Coroa de Proteína , Coroa de Proteína/metabolismo , Proteínas , Sistemas de Liberação de Medicamentos/métodos , Membrana Celular/metabolismo
8.
Int J Pharm ; 649: 123669, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38056797

RESUMO

Multidrug resistance (MDR) is a public health issue of particular concern, for which nanotechnology-based multidrug delivery systems are considered among the most effective suppressive strategies for such resistance in tumors. However, for such strategies to be viable, the notable shortcomings of reduced loading efficiency and uncontrollable drug release ratio need to be addressed. To this end, we developed a novel "multidrug/material" co-delivery system, using d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS, P-gp efflux pump inhibitor) and poly(amidoamine) (PAMAM) to fabricate a precursor material with the properties of reversing MDR and having a long-cycle. Further, to facilitate multidrug co-delivery, we loaded doxorubicin(Dox) and curcumin(Cur, cardiotoxicity modifier and P-gp inhibitor) into PAMAM-TPGS nano-micelles respectively, and mixed in appropriate proportions. The multidrug/material co-delivery system thus obtained was characterized by high drug loading and a controllable drug release ratio in the physiological environment. More importantly, in vitro and in vivo pharmacodynamic studies indicated that the multidrug/material co-delivery system facilitated the reversal of MDR. Moreover, the system has increased anti-tumor activity and is biologically safe. We accordingly propose that the "multidrug/material" co-delivery system developed in this study could serve as a potential platform for reversing MDR and achieving safe and effective clinical treatment.


Assuntos
Antineoplásicos , Resistencia a Medicamentos Antineoplásicos , Humanos , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Resistência a Múltiplos Medicamentos , Micelas , Vitamina E/farmacologia , Polietilenoglicóis/farmacologia , Antineoplásicos/farmacologia , Células MCF-7
9.
Int J Biol Macromol ; 256(Pt 1): 128395, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38000330

RESUMO

In the present study, a pectin-like apple polysaccharide (AP) obtained by metal precipitation technique was demonstrated to show strong gelling capacity in the presence of K+ ion upon cooling. Increasing amount of K+ addition monotonically promoted the gelation of AP, as characterized by the increased gelation temperature (Tgel), gel melting temperature (Tmelt) and the gel strength. Compared with K+ ion, Na+ was unable to induce AP gelation even at high ionic concentrations, but other monovalent cations (Rb+, Cs+) can induce the gelation as in the case of K+ addition. At room temperature, the minimum cationic concentration as required to induce AP gelation followed the order of K+ ≈ Cr+ (8 mM) > Rb+ (3.5 mM), indicating that cationic radius (Na+ < K+ < Rb+ < Cs+) played a dominant role in inducing AP gelation, but other factors may also be involved. Finally, the gelation behavior of AP in the presence of K+ was explained as the suppressed intermolecular electrostatic repulsion between AP chains due to the strong electrostatic shielding effect of K+, which led to the formation of a gel network mediated by intermolecular hydrogen bonding. This reported gelation property may allow AP to find application as a new gelling polysaccharide.


Assuntos
Pectinas , Polissacarídeos , Concentração de Íons de Hidrogênio , Íons , Géis , Reologia
10.
Chem Asian J ; 19(1): e202300872, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37945534

RESUMO

Although molecular self-assembled porous materials capable of ratiometric fluorescence probing and recycling of metal ions are both economically and environmentally attractive, very few current efforts have been devoted. Herein, we demonstrated a three-dimensional pure organic cage, namely 4-cage, which can serve as a fluorescent probe for simultaneous ratiometric detection and recycling of Ag+ ion. Taking advantage of the promising emission behavior of its rigidified tetraphenylethylene scaffolds and the chelating ability of its dynamically reversible imine moieties, on one hand, upon the addition of Ag+ , 4-cage undergoes coordination to form a stable but poorly soluble fluorescent complex, Ag+ @4-cage, accompanied by a fluorescence color change from bluish-green to yellowish-green. This allows us to differentiate Ag+ from other cations with high selectivity. On the other hand, upon the addition of Cl- anion, Ag+ @4-cage can be effectively converted into free 4-cage due to the competitive coordination of Cl- with Ag+ . Through this process, secondary usage of 4-cage and the recycling of Ag+ ion can be achieved.

11.
Nucleic Acids Res ; 52(D1): D747-D755, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37930867

RESUMO

Protists, a highly diverse group of microscopic eukaryotic organisms distinct from fungi, animals and plants, exert crucial roles within the earth's biosphere. However, the genomes of only a small fraction of known protist species have been published and made publicly accessible. To address this constraint, the Protist 10 000 Genomes Project (P10K) was initiated, implementing a specialized pipeline for single-cell genome/transcriptome assembly, decontamination and annotation of protists. The resultant P10K database (https://ngdc.cncb.ac.cn/p10k/) serves as a comprehensive platform, collating and disseminating genome sequences and annotations from diverse protist groups. Currently, the P10K database has incorporated 2959 genomes and transcriptomes, including 1101 newly sequenced datasets by P10K and 1858 publicly available datasets. Notably, it covers 45% of the protist orders, with a significant representation (53% coverage) of ciliates, featuring nearly a thousand genomes/transcriptomes. Intriguingly, analysis of the unique codon table usage among ciliates has revealed differences compared to the NCBI taxonomy system, suggesting a need to revise the codon tables used for these species. Collectively, the P10K database serves as a valuable repository of genetic resources for protist research and aims to expand its collection by incorporating more sequenced data and advanced analysis tools to benefit protist studies worldwide.


Assuntos
Bases de Dados Genéticas , Eucariotos , Fungos , Genoma , Animais , Códon , Eucariotos/genética , Fungos/genética , Plantas/genética
12.
Int J Biol Macromol ; 257(Pt 1): 128658, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38065446

RESUMO

Nanodrug delivery systems based on tumor microenvironment responses have shown excellent performance in tumor-targeted therapy, given their unique targeting and drug-release characteristics. Matrix metalloproteinases (MMPs) have been widely explored owing to their high specificity and expression in various tumor microenvironments. The design of an enzyme-sensitive nanodelivery system using MMPs as targeted receptors could markedly improve the performance of drug targeting. The current review focuses on the development and application of MMP-responsive drug carriers, and summarizes the classification of single- and multi-target nanocarriers based on their MMP responsiveness. The potential applications and challenges of this nanodrug delivery system are discussed to provide a reference for designing high-performance nanodrug delivery systems.


Assuntos
Nanopartículas , Neoplasias , Humanos , Sistemas de Liberação de Medicamentos , Portadores de Fármacos/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Sistemas de Liberação de Fármacos por Nanopartículas , Microambiente Tumoral , Metaloproteinases da Matriz
13.
J Hazard Mater ; 465: 133115, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38096614

RESUMO

Microplastic pollution in freshwater environments has received increasing attention. However, limited research on the occurrence and distribution of microplastics in plateau lakes. This study investigated the microplastic characteristics and influencing factors in lakes with different land cover types on the Inner Mongolia Plateau. Results showed that microplastic abundance ranged from 0.5 to 12.6 items/L in water and 50-325 items/kg in sediments. Microplastics in water were predominantly polypropylene (50.5%), fragments (40.5%), and 50-200 µm (66.7%). High-density (27.9%), fibrous (69.3%), and large-sized microplastics (47.7%) were retained primarily in lake sediments. The highest microplastic abundance in water was found in cropland lakes and grassland lakes, while that in sediments was in descending order of desert lakes > cropland lakes > grassland lakes > forest-grassland lakes. Differences among lake types suggest that agriculture, tourism, and atmospheric transport may be critical microplastic sources. Microplastic distribution was positively correlated with farmland and artificial surface coverage, showing that land cover types related to human activities could exacerbate microplastic pollution in lakes. Redundancy analysis showed that ammonia nitrogen and pH were the key physicochemical factors affecting microplastic distribution in lakes, indicating the potential sources of microplastics in lakes and the uniqueness of microplastic occurrence characteristics in desert saline-alkaline lakes, respectively.

14.
Huan Jing Ke Xue ; 44(12): 6933-6946, 2023 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-38098416

RESUMO

Taking the soil of a petrochemical site in Chongqing as the research object, the pollution sources of heavy metals and volatile organic pollutants in the study area were quantitatively analyzed using principal component analysis and a positive definite matrix decomposition model. The research results showed that:① the average values of Cd, Cu, Pb, Hg, and Mn in the soil of the petrochemical site and its surrounding areas were higher than the soil background values in Chongqing, and the content of Co in 6% of sampling points was higher than the risk screening value of the first type of land use for construction land(GB 36600-2018). The pollution level of Hg, Mn, chloroform, ethylbenzene, m/p-xylene, and o-xylene in the soil of the site was more serious than that of the soil around the site. The industrial production activities of the site will cause significant pollution to the soil of the site. ② Eight heavy metals in the soil could be classified into four sources:62.50% Cd, 54.53% Ni, 54.12% Cu, 51.26% Co, 49.34% Pb, and 31.80% Hg were from the mixed sources of industrial emissions and agricultural activities. A total of 47.61% Mn was from the mixed source of natural and raw material production activities; 62.79% Hg, 21.57% As, 19.43% Mn, and 18.42% Cd were from the emission of coal-fired industrial activities; and 78.01% As, 46% Pb, 39.94% Cu, 38.15% Ni, 36.49% Co, 26.12% Mn, and 14.29% Cd were from the original material soil. ③ Seven volatile organic compounds in the soil of the site were mainly classified into three types of sources:86.49% dichloromethane and 90.14% tetrachloroethylene were from human activities in petrochemical sites; 98.88% m/p-xylene, 96.28% o-xylene, 84.62% ethylbenzene, and 76.46% toluene were from petrochemical site pollutant leakage sources; and 80.24% chloroform was from the natural sources.

15.
Front Cell Dev Biol ; 11: 1329840, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38099293

RESUMO

Human mesenchymal stem cells (hMSCs) are multipotent progenitor cells with the potential to differentiate into various cell types, including osteoblasts, chondrocytes, and adipocytes. These cells have been extensively employed in the field of cell-based therapies and regenerative medicine due to their inherent attributes of self-renewal and multipotency. Traditional approaches for assessing hMSCs differentiation capacity have relied heavily on labor-intensive techniques, such as RT-PCR, immunostaining, and Western blot, to identify specific biomarkers. However, these methods are not only time-consuming and economically demanding, but also require the fixation of cells, resulting in the loss of temporal data. Consequently, there is an emerging need for a more efficient and precise approach to predict hMSCs differentiation in live cells, particularly for osteogenic and adipogenic differentiation. In response to this need, we developed innovative approaches that combine live-cell imaging with cutting-edge deep learning techniques, specifically employing a convolutional neural network (CNN) to meticulously classify osteogenic and adipogenic differentiation. Specifically, four notable pre-trained CNN models, VGG 19, Inception V3, ResNet 18, and ResNet 50, were developed and tested for identifying adipogenic and osteogenic differentiated cells based on cell morphology changes. We rigorously evaluated the performance of these four models concerning binary and multi-class classification of differentiated cells at various time intervals, focusing on pivotal metrics such as accuracy, the area under the receiver operating characteristic curve (AUC), sensitivity, precision, and F1-score. Among these four different models, ResNet 50 has proven to be the most effective choice with the highest accuracy (0.9572 for binary, 0.9474 for multi-class) and AUC (0.9958 for binary, 0.9836 for multi-class) in both multi-class and binary classification tasks. Although VGG 19 matched the accuracy of ResNet 50 in both tasks, ResNet 50 consistently outperformed it in terms of AUC, underscoring its superior effectiveness in identifying differentiated cells. Overall, our study demonstrated the capability to use a CNN approach to predict stem cell fate based on morphology changes, which will potentially provide insights for the application of cell-based therapy and advance our understanding of regenerative medicine.

16.
Int Microbiol ; 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37987892

RESUMO

We determined whether there exists a complementary pathway of cordycepin biosynthesis in wild-type Cordyceps militaris, high-cordycepin-producing strain C. militaris GYS60, and low-cordycepin-producing strain C. militaris GYS80. Differentially expressed genes were identified from the transcriptomes of the three strains. Compared with C. militaris, in GYS60 and GYS80, we identified 145 and 470 upregulated and 96 and 594 downregulated genes. Compared with GYS80, in GYS60, we identified 306 upregulated and 207 downregulated genes. Gene Ontology analysis revealed that upregulated genes were mostly involved in detoxification, antioxidant, and molecular transducer in GYS60. By Clusters of Orthologous Groups of Proteins and Kyoto Encyclopedia of Genes and Genomes analyses, eight genes were significantly upregulated: five genes related to purine metabolism, one to ATP production, one to secondary metabolite transport, and one to RNA degradation. In GYS60, cordycepin was significantly increased by upregulation of ATP production, which promoted 3',5'-cyclic AMP production. Cyclic AMP accelerated 3'-AMP accumulation, and cordycepin continued to be synthesized and exported. We verified the novel complementary pathway by adding the precursor adenosine and analyzing the expression of four key genes involved in the main pathway of cordycepin biosynthesis. Adenosine addition increased cordycepin production by 51.2% and 10.1%, respectively, in C. militaris and GYS60. Four genes in the main pathway in GYS60 were not upregulated.

17.
Analyst ; 148(24): 6261-6273, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-37937546

RESUMO

Long non-coding RNAs (lncRNA) are non-protein coding RNA molecules that are longer than 200 nucleotides. The lncRNA molecule plays diverse roles in gene regulation, chromatin remodeling, and cellular processes, influencing various biological pathways. However, probing the complex dynamics of lncRNA in live cells is a challenging task. In this study, a double-stranded gapmer locked nucleic acid (ds-GapM-LNA) nanobiosensor is designed for visualizing the abundance and expression of lncRNA in live human bone-marrow-derived mesenchymal stem cells (hMSCs). The sensitivity, specificity, and stability were characterized. The results showed that this ds-GapM-LNA nanobiosensor has very good sensitivity, specificity, and stability, which allows for dissecting the regulatory roles of cellular processes during dynamic physiological events. By incorporating this nanobiosensor in living hMSC imaging, we elucidated lncRNA MALAT1 expression dynamics during osteogenic and adipogenic differentiation. The data reveal that lncRNA MALAT1 expression is correlated with distinct sub-stages of osteogenic and adipogenic differentiation.


Assuntos
MicroRNAs , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , Diferenciação Celular/fisiologia , Adipogenia/genética , Oligonucleotídeos , Osteogênese/genética , MicroRNAs/genética
18.
Anal Chim Acta ; 1282: 341909, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37923406

RESUMO

BACKGROUND: Dual atomic site catalysts (DASCs) have aroused extensive interest in analytical chemistry on account of the superb catalytic activity caused by the highly-exposed active centers and synergistic effect of adjacent active centers. The reported protocols for preparing DASCs usually involve harsh conditions such as acid/base etching and high-temperature calcination, leading to unfavorable water dispersity and restricted application. It is crucial to develop DASCs with satisfactory water dispersity, improved stability, and mild preparation procedures to facilitate their application as signal probes in analytical chemistry. RESULTS: Formic acid was adopted as a modulator for preparing MOF-808 with abundant defective sites, which was used as the carrier for implanting Co atoms. Co DASCs with a special coordination structure of Co2-O10 and a high loading efficiency of 11.1 wt% were prepared with a mild solvothermal protocol. The resultant Co DASCs can significantly accelerate decay of H2O2 for forming numerous reactive oxygen radicals and boost chemiluminescent (CL) signal. Co DASCs at 1.0 µg mL-1 can enhance the CL signal of luminol-H2O2 system by about 5800 times. Thanks to their satisfactory water dispersity and excellent CL enhancement performance, they were used as ultra-sensitive CL signal probes for monitoring methicillin-resistant Staphylococcus aureus. The method shows a detection range of 102-107 CFU mL-1 and a detection limit of 47 CFU mL-1. Antibiotic susceptibility test was performed with the established CL method to prove its practicality. SIGNIFICANCE: The water dispersible Co DASCs prepared with facile and mild solvothermal protocol exhibit prominent peroxidase-like activity and can promote the production of reactive oxygen radicals for boosting CL signal. Therefore, this study paves an avenue for implanting DASCs in defect-engineered carrier to prepare signal probes suitable for development of ultra-sensitive CL analytical methods.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Espécies Reativas de Oxigênio , Peróxido de Hidrogênio/química , Medições Luminescentes/métodos , Luminol/química , Bactérias , Água
19.
Microorganisms ; 11(10)2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37894156

RESUMO

Microbial communities are essential components of aquatic ecosystems and are widely employed for the detection, protection, and restoration of water ecosystems. The polyurethane foam unit (PFU) method, an effective and widely used environmental monitoring technique, has been improved with the eDNA-PFU method, offering efficiency, rapidity, and standardization advantages. This research aimed to explore the colonization process of microbial communities within PFUs using eDNA-PFU technology. To achieve this, we conducted ten-day monitoring and sequencing of microbial communities within PFUs in a stable and controlled artificial aquatic ecosystem, comparing them with water environmental samples (eDNA samples). Results showed 1065 genera in eDNA-PFU and 1059 in eDNA, with eDNA-PFU detecting 99.95% of eDNA-identified species. Additionally, the diversity indices of bacteria and eukaryotes in both methods showed similar trends over time in the colonization process; however, relative abundance differed. We further analyzed the colonization dynamics of microbes in eDNA-PFU and identified four clusters with varying colonization speeds. Notably, we found differences in colonization rates between bacteria and eukaryotes. Furthermore, the Molecular Ecological Networks (MEN) showed that the network in eDNA-PFU was more modular, forming a unique microbial community differentiated from the aquatic environment. In conclusion, this study, using eDNA-PFU, comprehensively explored microbial colonization and interrelationships in a controlled mesocosm system, providing foundational data and reference standards for its application in aquatic ecosystem monitoring and beyond.

20.
Int J Anal Chem ; 2023: 7436368, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37810911

RESUMO

Uterine adenosarcoma (UA) is an uncommon mixed tumor containing a benign to at most mildly atypical epithelial component and a sarcoma-like stroma, usually a low-grade, stromal component, with rare heterogeneous elements. Currently, tumor etiology is largely unknown. To better understand the gene mutations in UA, next-generation sequencing (NGS) technology analysis was performed. This study showed that two low-grade UAs with heterologous components had ATRX gene frameshift mutation, and one patient had a MED12 missense mutation. Copy number amplification genes were mainly observed on chromosome 12q13-15. In this study, PIK3/AKT/PTEN pathway mutations were found to be common in adenosarcoma. In addition, a rare BCORL1-PRR14L fusion mutation was also identified. These findings provide a basis for future research into these molecular changes in tumorigenesis and targeted therapy.

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