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1.
Heliyon ; 10(9): e30072, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38707322

RESUMEN

This study reconstructs the Early Pleistocene paleoenvironment of the Yuanmou Basin through coproecology of the third member of the Yuanmou Formation. We examined 38 exceptionally well-preserved coprolites from a new fossil locality, and attributed the putative defecating agent to the hypercarnivorous diet canid, Sinocuon yuanmouensis through geochemical and quantitative analyses. A new ichnogenus and ichnospecies, Cuocopros yuanmouensis igen. et. isp. nov., was established based on distinctive characteristics. Multi-disciplinary analysis, including sediment palynology and lithostratigraphy, helped primarily reconstruct a significant climatic event during the early Pleistocene, coinciding with the emergence of Yuanmou Man during the fourth member of the Yuanmou Formation's deposition. The findings provide insights into coexistence between canids, hyaenas, hominoids, and other fauna, revealing a rich paleoecosystem and food chain in the region's history. This study contributes to understanding the complex ecological dynamics during this period in the Yuanmou Basin.

2.
Stat Med ; 43(10): 2007-2042, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38634309

RESUMEN

Quantile regression, known as a robust alternative to linear regression, has been widely used in statistical modeling and inference. In this paper, we propose a penalized weighted convolution-type smoothed method for variable selection and robust parameter estimation of the quantile regression with high dimensional longitudinal data. The proposed method utilizes a twice-differentiable and smoothed loss function instead of the check function in quantile regression without penalty, and can select the important covariates consistently using the efficient gradient-based iterative algorithms when the dimension of covariates is larger than the sample size. Moreover, the proposed method can circumvent the influence of outliers in the response variable and/or the covariates. To incorporate the correlation within each subject and enhance the accuracy of the parameter estimation, a two-step weighted estimation method is also established. Furthermore, we prove the oracle properties of the proposed method under some regularity conditions. Finally, the performance of the proposed method is demonstrated by simulation studies and two real examples.


Asunto(s)
Algoritmos , Modelos Estadísticos , Humanos , Simulación por Computador , Modelos Lineales , Tamaño de la Muestra
3.
Chemosphere ; 349: 140842, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38048834

RESUMEN

Green and low carbon is an essential direction for the development of water treatment technology. Ozone catalysts prepared by the mixing method have advantages in terms of energy consumption and CO2 emissions, but are considered to be insufficient in catalytic efficiency and stability. In this paper, an Mn-Cu-Ce/Al2O3 (MCCA) catalyst was prepared by optimizing the preparation conditions of the mixing method and the types and ratios of active components. Taking petrochemical secondary effluent (PCSE) as the treatment object, the performance of the catalyst and the carbon emission in the preparation process were studied; and compared with the impregnation method. Results showed that compared with catalysts loaded with other components, the MCCA had a higher removal efficiency for TOC (43.04%) and COD (53.18%), which was basically equivalent to the impregnation method, and the treated effluent reached the expected concentration. MCCA promoted the decomposition rate of O3 by ten times, and the main active species generated were found to be •OH and 1O. Similar to the catalytic ozonation by the catalyst prepared by the impregnation method, the adsorption sites and surface hydroxyl groups on the MCCA surface play a significant role in the degradation of pollutants. However, the carbon emission in the catalyst preparation process of the mixing method was 418.68 kg/ton, which was only 44% of the impregnation method (949.67 kg/ton). Under the global low-carbon transition, this study shows that the mixing method aligns more with the concept of green, clean, and efficient ozone catalyst preparation.


Asunto(s)
Ozono , Contaminantes Químicos del Agua , Carbono , Aluminio , Ozono/química , Contaminantes Químicos del Agua/análisis , Óxido de Aluminio/química , Catálisis
4.
Front Pediatr ; 11: 1194186, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37808557

RESUMEN

Background: Pneumonia remains the leading cause of death among children aged 1-59 months. The early prediction of poor outcomes (PO) is of critical concern. This study aimed to explore the risk factors relating to PO in severe community-acquired pneumonia (SCAP) and build a PO-predictive nomogram model for children with SCAP. Methods: We retrospectively identified 300 Chinese pediatric patients diagnosed with SCAP who were hospitalized in the Affiliated Hospital of Southwest Medical University from August 1, 2018, to October 31, 2021. Children were divided into the PO and the non-PO groups. The occurrence of PO was designated as the dependent variable. Univariate and multivariate logistic regression analyses were used to identify the risk factors of PO. A nomogram model was constructed from the multivariate logistic regression analysis and internally validated for model discrimination and calibration. The performance of the nomogram was estimated using the concordance index (C-index). Results: According to the efficacy evaluation criteria, 56 of 300 children demonstrated PO. The multivariate logistic regression analysis resulted in the following independent risk factors for PO: co-morbidity (OR: 8.032, 95% CI: 3.556-18.140, P < 0.0001), requiring invasive mechanical ventilation (IMV) (OR: 7.081, 95% CI: 2.250-22.282, P = 0.001), and ALB < 35 g/L (OR: 3.203, 95% CI: 1.151-8.912, P = 0.026). Results of the internal validation confirmed that the model provided good discrimination (concordance index [C-index], 0.876 [95% CI: 0.828-0.925]). The calibration plots in the nomogram model were of high quality. Conclusion: The nomogram facilitated accurate prediction of PO in children diagnosed with SCAP and could be helpful for clinical decision-making.

5.
Chemosphere ; 337: 139386, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37394187

RESUMEN

Antibiotic-resistant bacteria, especially multi-antibiotic-resistant bacteria (MARBs), greatly threaten environmental safety and human health. However, studies on the phenotypic resistance and complete genotypic characterization of MARB in aquatic environments are lacking. In this study, a multi-resistant superbug (TR3) was screened by the selective pressure of multi-antibiotics from the activated sludge of the aeration tanks of urban wastewater treatment plants (WWTPs) in 5 different regions of China. Based on the 16 S rDNA sequence alignment it was found that the sequence similarity between strain TR3 and Aeromonas was as high as 99.50%. The genome-wide sequence showed that the base content of the chromosome of strain TR3 is 4,521,851 bp. It contains a plasmid with a length of 9182 bp. All antibiotic resistance genes (ARGs) of strain TR3 are located on the chromosome, which means that it has passage stability. There are multiple types of resistance genes in the genome and plasmid of strain TR3, enduing it with resistance to 5 antibiotics (ciprofloxacin, tetracycline, ampicillin, clarithromycin, and kanamycin), accompanied by the strongest resistance to kanamycin (aminoglycosides) and the worst resistance to clarithromycin (quinolones). From the perspective of gene expression, we show the resistance mechanism of strain TR3 to different types of antibiotics. In addition, the potential pathogenicity of strain TR3 is also discussed. Chlorine and ultraviolet (UV) sterilization on strain TR3 showed that UV is ineffective at low intensity, and it is easy to be revived by light. A low concentration of hypochlorous acid is effective for sterilization, but it can cause the release of DNA, becoming a potential source of ARGs discharged from WWTPs to environmental water bodies.


Asunto(s)
Antibacterianos , Aguas Residuales , Humanos , Antibacterianos/farmacología , Claritromicina , Eliminación de Residuos Líquidos , Bacterias/genética , Genes Bacterianos , Genómica , Kanamicina
6.
J Hazard Mater ; 451: 131199, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-36933504

RESUMEN

Microplastics (MPs) are ubiquitous in the environment and have been verified to be harmful to organisms. The petrochemical industry is a possible contributor, for it is the primary plastic producer but is not focused on. In this background, MPs in the influent, effluent, activated sludge, and expatriate sludge of a typical petrochemical wastewater treatment plant (PWWTP) were identified by the laser infrared imaging spectrometer (LDIR). It revealed that the abundances of MPs in the influent and effluent were as high as 10310 and 1280 items/L with a removal efficiency of 87.6%. The removed MPs accumulated in the sludge, and the MP abundances in activated and expatriate sludge reached 4328 and 10767 items/g, respectively. It is estimated that 1440,000 billion MPs might be released into the environment by the petrochemical industry in 2021 globally. For the specific PWWTP, 25 types of MPs were identified, among which Polypropylene (PP), Polyethylene (PE), and Silicone resin were dominant. All of the detected MPs were smaller than 350 µm, and those smaller than 100 µm prevailed. As for the shape, the fragment was dominant. The study confirmed the critical status of the petrochemical industry in releasing MPs for the first time.

7.
Environ Sci Ecotechnol ; 15: 100244, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36820151

RESUMEN

Catalytic ozonation is widely employed in advanced wastewater treatment owing to its high mineralization of refractory organics. The key to high mineralization is the compatibility between catalyst formulation and wastewater quality. Machine learning can greatly improve experimental efficiency, while fluorescence data can provide additional wastewater quality information on the composition and concentration of organics, which is conducive to optimizing catalyst formulation. In this study, machine learning combined with fluorescence spectroscopy was applied to develop ozonation catalysts (Mn/γ-Al2O3 catalyst was used as an example). Based on the data collected from 52 different catalysts, a machine-learning model was established to predict catalyst performance. The correlation coefficient between the experimental and model-predicted values was 0.9659, demonstrating the robustness and good generalization ability of the model. The range of the catalyst formulations was preliminarily screened by fluorescence spectroscopy. When the wastewater was dominated by tryptophan-like and soluble microbial products, the impregnation concentration and time of Mn(NO3)2 were less than 0.3 mol L-1 and 10 h, respectively. Furthermore, the optimized Mn/γ-Al2O3 formulation obtained by the model was impregnation with 0.155 mol L-1 Mn(NO3)2 solution for 8.5 h and calcination at 600 °C for 3.5 h. The model-predicted and experimental values for total organic carbon removal were 54.48% and 53.96%, respectively. Finally, the improved catalytic performance was attributed to the synergistic effect of oxidation (•OH and 1O2) and the Mn/γ-Al2O3 catalyst. This study provides a rapid approach to catalyst design based on the characteristics of wastewater quality using machine learning combined with fluorescence spectroscopy.

8.
J Environ Sci (China) ; 124: 330-349, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36182143

RESUMEN

With the continuous development of nanomaterials in recent years, the application of nanocatalysts in catalytic ozone oxidation has attracted more and more researchers' attention due to their excellent catalytic properties. In this review, we systematically summarized the current research status of nanocatalysts mainly involving material categories, mechanisms and catalytic efficiency. Based on summary and analysis, we found most of the reported nanocatalysts were in the stage of laboratory research, which was caused by the nanocatalysts defects such as easy aggregation, difficult separation, and easy leakage. These defects might result in severe resource waste, economic loss and potentially adverse effects imposed on the ecosystem and human health. Aiming at solving these defects, we further analyzed the reasons and the existing reports, and revealed that coupling nano-catalyst and membrane, supported nanocatalysts and magnetic nanocatalysts had promising potential in solving these problems and promoting the actual application of nanocatalysts in wastewater treatment. Furthermore, the advantages, shortages and our perspectives of these methods are summarized and discussed.


Asunto(s)
Ozono , Contaminantes Químicos del Agua , Purificación del Agua , Catálisis , Ecosistema , Humanos , Aguas Residuales , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos
9.
J Appl Stat ; 49(14): 3677-3692, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36246863

RESUMEN

Variable selection is fundamental to high dimensional statistical modeling, and many approaches have been proposed. However, existing variable selection methods do not perform well in presence of outliers in response variable or/and covariates. In order to ensure a high probability of correct selection and efficient parameter estimation, we investigate a robust variable selection method based on a modified Huber's function with an exponential squared loss tail. We also prove that the proposed method has oracle properties. Furthermore, we carry out simulation studies to evaluate the performance of the proposed method for both pn. Our simulation results indicate that the proposed method is efficient and robust against outliers and heavy-tailed distributions. Finally, a real dataset from an air pollution mortality study is used to illustrate the proposed method.

10.
J Environ Manage ; 323: 116302, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36150350

RESUMEN

It was an important discovery in wastewater treatment that the microorganisms in the traditional activated sludge can form aerobic granular sludge (AGS) by self-aggregation under appropriate water quality and operation conditions. With a typical three-dimensional spherical structure, AGS has high sludge-water separation efficiency, great treatment capacity, and strong tolerance to toxic and harmful substances, so it has been considered to be one of the most promising wastewater treatment technologies. This paper comprehensively reviewed AGS from multiple perspectives over the past two decades, including the culture conditions, granulation mechanisms, metabolic and structural stability, storage, and its diverse applications. Some important issues, such as the reproducibility of culture conditions and the structural and functional stability during application and storage, were also summarized, and the research prospects were put forward. The aggregation behavior of microorganisms in AGS was explained from the perspectives of physiology and ecology of complex populations. The storage of AGS is considered to have large commercial potential value with the increase of large-scale applications. The purpose of this paper is to provide a reference for the systematic and in-depth study on the sludge aerobic granulation process.


Asunto(s)
Aguas del Alcantarillado , Eliminación de Residuos Líquidos , Aerobiosis , Reactores Biológicos , Reproducibilidad de los Resultados , Aguas del Alcantarillado/química , Eliminación de Residuos Líquidos/métodos , Aguas Residuales
11.
Front Pharmacol ; 13: 978019, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36147348

RESUMEN

Polycystic ovary syndrome (PCOS) is a complex endocrine disorder syndrome characterized by polycystic ovary, ovulation disorder and hyperandrogenemia, and is often accompanied by metabolic disorders. Enoxacin has been reported to protect against diet-induced obesity and insulin resistance by promoting fat thermogenesis. However, the function of enoxacin in PCOS remains unknown. This study aimed to investigate the impact of the enoxacin on the regulation of PCOS mouse model induced by dehydroepiandrosterone (DHEA). Here, we found that reproductive endocrine disorder, glucose intolerance, and ovarian dysfunction in PCOS mice induced by DHEA were attenuated by enoxacin treatment. Mechanistically, we identified that enoxacin can promote white fat browning and improve metabolic disorders, thus ameliorating DHEA-induced reproductive dysfunction. Moreover, these beneficial effects might be associated with the restoration of gut dysbiosis. These findings provide a novel therapeutic target for enoxacin in the treatment of PCOS.

12.
Environ Sci Pollut Res Int ; 29(56): 84861-84872, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35788489

RESUMEN

The petrochemical secondary effluent (PSE) is typical refractory wastewater derived from the petrochemical industries, which requires advanced treatment due to the strict environmental protection policies. Catalytic ozonation is one of the most widely used advanced oxidation technologies in wastewater treatment because of its high mineralization rate, in which the alumina-based catalyst usually plays an important role. Extrusion-spheronization is a promising technique for the preparation of alumina spheres because the synthesized alumina particles have high sphericity, high specific surface aera and narrow particle size distribution. In this paper, two kinds of alumina-based catalysts (catalyst A: manganese nitrate added after alumina granulation and catalyst B: manganese nitrate added into alumina powder before granulation) were prepared by the extrusion-spheronization method and used for PSE treatment by catalytic ozonation. The prepared alumina samples were characterized by Brunauer-Emmett-Teller (BET) method, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and scanning electron microscopy (SEM), while the wastewater samples were analyzed for Total organic carbon (TOC), UV254 and fluorescence spectroscopy. Results showed that manganese was uniformly distributed in both catalysts, and the specific surface area of two catalysts was 318.36 m2/g and 354.95 m2/g, respectively. Catalytic ozonation experiments were repeated nine times with each catalyst under the same conditions. The TOC removal rates for catalysts A and B in the first run were 48.88% and 49.06%, respectively, then it dropped to 28.05% for catalyst A but remained 47.81% for catalyst B after using for nine times. This implied that the long-term performance of catalyst B would be more stable than catalyst A. Similar result were found in three-dimensional fluorescence analysis. UV254 results indicated that the removal efficiency of aromatic and unsaturated substances by catalyst B was higher than catalyst A. A possible explanation is that the active component manganese oxide formed a catalyst skeleton in catalyst B, which makes it hard to dissolve. Effect of extrusion-spheronization granulation and manganese loading on advanced oxidant treatment of petrochemical wastewater.


Asunto(s)
Ozono , Contaminantes Químicos del Agua , Aguas Residuales/química , Manganeso/química , Ozono/química , Nitratos/análisis , Contaminantes Químicos del Agua/análisis , Catálisis , Óxido de Aluminio
13.
Drug Des Devel Ther ; 16: 1931-1945, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35762015

RESUMEN

Purpose: Anoectochilus roxburghii (Wall.) Lindl. polysaccharides (ARPs) have been reported to exhibit multiple pharmacological activities including anti-inflammatory and anti-hyperglycemia. This study aims to investigate the effect of ARPs on cognitive dysfunction induced by high fat diet (HFD). Methods: Six-week-old male mice were treated with ARPs by dietary supplementation for 14 weeks. The effect of ARPs on cognitive function was determined by assessing the changes in spatial learning and memory ability, neurotrophic factors in hippocampus, inflammatory parameters, intestinal barrier integrity, and gut microbiota. Results: ARPs supplementation can effectively ameliorate cognitive dysfunction, decrease the phosphorylation levels of Tau protein in hippocampus. Meanwhile, the increased body weight, plasma glucose, total cholesterol, inflammatory factors induced by HFD were abolished by ARPs treatment. Furthermore, ARPs treatment restored the intestinal epithelial barrier as evidenced by upregulation of intestinal tight junction proteins. Additionally, ARPs supplementation significantly decreased the relative abundance of several bacteria genus such as Parabacteroides, which may play regulatory roles in cognitive function. Conclusion: These results suggest that ARPs might be a promising strategy for the treatment of cognitive dysfunction induced by HFD. Mechanistically, alleviation of cognitive dysfunction by ARPs might be associated with the "gut-brain" axis.


Asunto(s)
Disfunción Cognitiva , Orchidaceae , Animales , Encéfalo , Disfunción Cognitiva/tratamiento farmacológico , Dieta Alta en Grasa , Suplementos Dietéticos , Masculino , Ratones , Ratones Endogámicos C57BL , Polisacáridos/farmacología , Polisacáridos/uso terapéutico
14.
Sci Total Environ ; 830: 154803, 2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35341845

RESUMEN

Heterogeneous catalytic oxidation, as an efficient advanced treatment technology, has been gradually applied in industrial wastewater treatment. The fixed bed technique is one of the most popular catalytic ozonation methods. However, few studies have concentrated on the long-term operation effects on catalysts. In this study, we conducted long-term (~5 years) observations of the operation of the largest petrochemical wastewater treatment plant (treatment capacity 120,000 m3/d) with catalytic ozonation technology in China. A commercial catalyst, which uses Al2O3 pellets supporting copper oxide was applied in this plant. The results showed that the catalytic efficiency gradually decreased from 60.65% to 25.98% since 2018, and the ozone dosage to COD removal ratio (ozone/COD) also increased from 0.82 to 1.93 mg/mg as the running time continued. By means of the comparison and characterization of fresh catalyst and used catalyst, a "mucus layer" was formed by the adsorption of negatively charged extracellular polymeric substances on the positively charged catalyst surface and the interception of the catalyst layer. The mucus layer significantly reduced the catalytic efficiency by isolating ozone with catalytic active sites and releasing extra organic contaminants during the catalytic process resulting in 53.97% TOC increase in the batch test. Meanwhile, regeneration experiments revealed that the TOC removal efficiency was 4.76% and 43.48% in presence of washed catalysts and calcinated catalysts, respectively. Compared with the fresh catalyst, 73% of the catalytic activity was recovered for calcinated catalyst. Consequently, this study provides much practical information, showing positive effects on the promotion of catalytic ozonation application in actual wastewater treatment.


Asunto(s)
Ozono , Contaminantes Químicos del Agua , Purificación del Agua , Catálisis , Ozono/química , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos
15.
Phytomedicine ; 99: 154031, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35272243

RESUMEN

BACKGROUND: Recent studies have shown that polysaccharides from Anoectochilus roxburghii (Wall.) Lindl. (ARPs) can reduce blood glucose levels, ameliorate oxidative stress and inflammation. However, whether ARPs have a beneficial effect on diet-induced obesity remain to be determined. PURPOSE: This study aims to investigate the effect and mechanism of ARPs in improving obesity and metabolic disorders induced by high-fat diet (HFD). METHODS: In this study, 6-week-old male mice were fed with HFD or chow diet for 13 weeks, and a dietary supplementation with ARPs was carried out. Glucose tolerance test and insulin tolerance test were performed to measure the glucose tolerance and insulin sensitivity. Adipose tissue and liver were isolated for analysis by qRT-PCR, Western blotting, hematoxylin-eosin staining and immunostaining. RESULTS: At week 13, body weight and fat mass were significantly increased by HFD, but ARPs supplementation abolished these phenotypes. Compared with HFD group, thermogenic genes including Ucp-1, Pgc-1α, Prdm16 and Dio2 in adipose tissue were up-regulated in ARPs-treated mice. In addition, ARPs decreased liver lipid accumulation by reducing lipid synthesis and increasing oxidation. Meanwhile, dyslipidemia and insulin resistance induced by HFD were improved by ARPs. Mechanistically, ARPs can promote fat thermogenesis via AMPK/SIRT1/PGC-1α signaling pathway. CONCLUSION: Dietary supplementation of ARPs can protect mice against diet-induced obesity, fatty liver and insulin resistance. Our study reveals a potential therapeutic effect for ARPs in regulating energy homeostasis.

16.
Sci Total Environ ; 816: 151554, 2022 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-34774630

RESUMEN

In this study, the excess activated sludge was used for pyrolysis to produce biochar with Ce modification. The removal process and mechanism of ampicillin resistance gene (ARGAmp) by biochar was investigated. The results showed that when pyrolyzing the excess sludge at 400 °C, the organic components in the sludge could be partially pyrolyzed and complexed with Ce. By accepting electrons from phenol or quinone, persistent free radicals (PFRs) were formed on the surface of biochar. On the optimized conditions with the initial ARGAmp concentration of 41.43 mg/L, the removal ratios of ARGAmp by adsorption, PFRs, hydroxyl free radicals (·OH) by adding H2O2 were 28.37%, 8.26%, and 27.56%. No melted DNA was detected in the treated samples. The oxidation process by PFRs and ·OH can directly destroy the ARGAmp structure. The phosphodiester bond in the base stacking structure and the phosphate bond in the nucleotide are the possible action sites of PFRs. Treated ARGAmp products were in the form of base pair residues or short-chain double helix structures. ·OH can be added to the bases of nucleotide molecules to form highly active free radical adducts. They can initiate molecular dehydrogenation and intermolecular proton transfer, resulting in oxidation of the base to the scission of the phosphate sugar backbone.


Asunto(s)
Antibacterianos , Peróxido de Hidrógeno , Adsorción , Carbón Orgánico , Farmacorresistencia Microbiana , Aguas del Alcantarillado
17.
Anal Chem ; 94(2): 732-739, 2022 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-34932901

RESUMEN

The establishment of rapid targeted identification and analysis of antibiotic resistance genes (ARGs) is very important. In this study, an electrochemical sensor, which can detect ARGs was obtained by modifying the sulfhydryl single-stranded DNA probe onto the thin-film gold electrode through self-assembly. The sensor can perform a hybridization reaction with a target sequence to obtain an electrochemical impedance spectroscopy signal. The results showed that when the concentration of the probe used to modify thin-film gold electrodes during preparation was 1 µM, the hybridization time was 1 h, and the hybridization temperature was 35 °C, the self-assembled sensor showed good detection performance for the ARGs encoding ß-lactam hydrolase. The measurement ARG concentration linear range is 6.3-900.0 ng/mL, and the R2 is 0.9992. The sensor shows good specific recognition ability for single-base, double-base, and three-base mismatch DNA. In addition, after 30 days of storage at 4 °C, the accurate identification and analysis of ARGs can still be maintained.


Asunto(s)
Técnicas Biosensibles , Antibacterianos/farmacología , Técnicas Biosensibles/métodos , Farmacorresistencia Microbiana/genética , Técnicas Electroquímicas , Electrodos , Oro/química , Hibridación de Ácido Nucleico , Agua
18.
Environ Sci Pollut Res Int ; 29(17): 24941-24950, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34826078

RESUMEN

In this study, the interaction between river sediments collected from cold regions and typical antibiotics was investigated. The results show that tetracycline addition to the sediment can promote the fluorescence quenching of protein-like, marine humic acid, and humic acid-like substances. The degree of quenching increased with the increase of tetracycline concentration (0-80 µM). The fluorescence quenching degree of protein-like, marine humic acid, and humic acid-like substances is as high as 94.76%, 70.19%, and 77.80%, respectively. In addition, the process belongs to static quenching, and a ground-state complex is formed during the quenching reaction. The number of binding sites of tetracycline and protein-like, marine humic acid, and humic acid-like substances is 1.30, 1.51, and 1.34, respectively. The order of the strength of the formed complex is marine-like humic acid, protein-like, and humic acid-like substrates. The secondary structure of protein-like substrate in the sediment organic matter includes three types: aggregated strands, ß-Sheet, and α-helix; and the content ratios are 10.23%, 8.33%, and 81.44%, respectively. When the concentration of tetracycline increased to 80 µM, the content of ß-sheet increased significantly, while the content of α-helix decreased significantly. 2D-COS analysis showed that the reaction sequence of organic functional groups and tetracycline in the sediment was phenolic hydroxyl group, fatty group of amino acid structure, nonfluorescent polysaccharide, and protein-like α-helix substrates. After tetracycline interacts with water-extractable organic matters (WEOM), the structure of WEOM becomes compact, and its adsorption capacity on the surface of minerals is significantly reduced, resulting in an increase in the fluidity of tetracycline in the water environment.


Asunto(s)
Sustancias Húmicas , Ríos , Antibacterianos/análisis , Sedimentos Geológicos/química , Sustancias Húmicas/análisis , Ríos/química , Tetraciclina , Agua/análisis
19.
J Cell Mol Med ; 26(3): 800-812, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34953044

RESUMEN

Both androgen receptor (AR) and the ZFHX3 transcription factor modulate prostate development. While AR drives prostatic carcinogenesis, ZFHX3 is a tumour suppressor whose loss activates the PI3K/AKT signalling in advanced prostate cancer (PCa). However, it is unknown whether ZFHX3 and AR are functionally related in PCa cells and, if so, how. Here, we report that in AR-positive LNCaP and C4-2B PCa cells, androgen upregulates ZFHX3 transcription via androgen-induced AR binding to the androgen-responsive elements (AREs) of the ZFHX3 promoter. Androgen also upregulated ZFHX3 transcription in vivo, as castration dramatically reduced Zfhx3 mRNA and protein levels in mouse prostates, and ZFHX3 mRNA levels correlated with AR activities in human PCa. Interestingly, the binding of AR to one ARE occurred in the absence of androgen, and the binding repressed ZFHX3 transcription as this repressive binding was interrupted by androgen treatment. The enzalutamide antiandrogen prevented androgen from inducing ZFHX3 transcription and caused excess ZFHX3 protein degradation. In human PCa, ZFHX3 was downregulated and the downregulation correlated with worse patient survival. These findings establish a regulatory relationship between AR and ZFHX3, suggest a role of ZFHX3 in AR function and implicate ZFHX3 loss in the antiandrogen therapies of PCa.


Asunto(s)
Proteínas de Homeodominio , Neoplasias de la Próstata , Receptores Androgénicos , Andrógenos/metabolismo , Animales , Línea Celular Tumoral , Proteínas de Homeodominio/metabolismo , Humanos , Masculino , Ratones , Fosfatidilinositol 3-Quinasas/metabolismo , Próstata/metabolismo , Neoplasias de la Próstata/patología , Receptores Androgénicos/genética , Receptores Androgénicos/metabolismo
20.
Chemosphere ; 289: 133140, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34863728

RESUMEN

In this study, the adsorption characteristics of marine dissolved organic matters (MDOMs) on the solid-liquid interface in the coastal waters was investigated. The results showed that the organic macromolecules with adsorption ability in MDOMs are not rigid molecules. However, the macromolecules have viscoelasticity properties. At different dilution ratios, the MDOMs adsorption process includes rapid (0-200 s) and slow adsorption (200 s later) periods. MDOMs adsorption in the solid-liquid interface is a dynamic process in which adsorption and hydration occur simultaneously. MDOMs concentration is an important driving force for adsorption. The three macromolecules of acid polysaccharides, protein-like, and polycarboxylate-type humic acids in MDOMs are rich in functional groups and they have the ability to absorb to solid surface. Acidic polysaccharides exhibit a sustained adsorption ability, while the adsorption of other macromolecules occurred only in the initial rapid adsorption period. In addition, the acid polysaccharides show weak thixotropy during the adsorption process. It would cause the stretching of macromolecular structure of the adsorption layer, enhancing the hydration of the adsorption layer. The study shows the adsorption process of MDOMs at the solid-liquid interface and the structural characteristics of the adsorption layer. It can provide helpful information for the inhibition and removal of MDOMs pollution during the actual development of marine resources.


Asunto(s)
Materia Orgánica Disuelta , Tecnicas de Microbalanza del Cristal de Cuarzo , Adsorción , Conformación Molecular , Propiedades de Superficie
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