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Irrigation practices and groundwater levels are critical factors contributing to soil salinization in arid and semi-arid regions. However, the impact of soil salinization resulting from Yellow River water irrigation and recharge on microbial communities and their functions in the Huinong District has not been thoroughly documented. In this study, high-throughput sequencing technology was employed to analyze the diversity, composition, and structure of bacterial and fungal communities across a gradient of salinized soils. The results indicated that the alpha diversity of bacterial communities was significantly higher in slightly saline soils compared to highly saline soils. Soil salinization notably influenced the composition of both bacterial and fungal communities. Highly salinized soils were enriched with bacterial taxa such as Halomonas, Salinimicrobium, Pseudomonas, Solibacillus, and Kocuria, as well as fungal taxa including Emericellopsis, Alternaria, and Podospora. In these highly saline soils, bacterial taxa associated with iron respiration, sulfur respiration, and hydrocarbon degradation were more prevalent, whereas fungal taxa linked to functions such as soil animal pathogens, arbuscular mycorrhizal symbiosis, endophytes, dung saprotrophy, leaf saprotrophy, soil saprotrophy, fungal parasitism, and plant pathogenicity were less abundant. Random forest analysis identified nine bacterial and eighteen fungal taxa as potential biomarkers for salinity discrimination in saline soils. Symbiotic network analysis further revealed that soil salinization pressure reduced the overall complexity and stability of bacterial and fungal communities. Additionally, bacterial community assembly showed a tendency shift from stochastic to deterministic processes in response to increasing salinity, while fungal community assembly remained dominated by deterministic processes. provide robust evidence that soil salinity is a major inhibitor of soil biogeochemical processes in the Huinong District and plays a critical role in shaping bacterial and fungal communities, their symbiotic networks, and their assembly processes.
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Protein post-translational modification (PTM) is a covalent process that occurs in proteins during or after translation through the addition or removal of one or more functional groups, and has a profound effect on protein function. Glycosylation is one of the most common PTMs, in which polysaccharides are transferred to specific amino acid residues in proteins by glycosyltransferases. A growing body of evidence suggests that glycosylation is essential for the unfolding of various functional activities in organisms, such as playing a key role in the regulation of protein function, cell adhesion and immune escape. Aberrant glycosylation is also closely associated with the development of various diseases. Abnormal glycosylation patterns are closely linked to the emergence of various health conditions, including cancer, inflammation, autoimmune disorders, and several other diseases. However, the underlying composition and structure of the glycosylated residues have not been determined. It is imperative to fully understand the internal structure and differential expression of glycosylation, and to incorporate advanced detection technologies to keep the knowledge advancing. Investigations on the clinical applications of glycosylation focused on sensitive and promising biomarkers, development of more effective small molecule targeted drugs and emerging vaccines. These studies provide a new area for novel therapeutic strategies based on glycosylation.
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Procesamiento Proteico-Postraduccional , Glicosilación , Humanos , Procesamiento Proteico-Postraduccional/genética , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patología , Glicosiltransferasas/genética , Glicosiltransferasas/metabolismo , Polisacáridos/metabolismo , Polisacáridos/genética , Polisacáridos/química , Enfermedades Autoinmunes/genética , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/patología , AnimalesRESUMEN
BACKGROUND: The global prospective surveillance data showed the re-emergence of mycoplasma pneumoniae pneumonia (MPP) in Europe and Asia after the coronavirus disease 2019 pandemic. We sought to observe the effect of macrolide antibiotics in the treatment of MPP carrying a macrolide-resistant mutation gene and the potential of targeted next-generation sequencing (tNGS) as a front-line diagnostic in MPP patients. METHODS: The baseline characteristics of 91 children with MPP hospitalized from January to October 2023 were retrospectively analyzed. They were divided into two groups according to whether carrying the macrolide-resistant mutation or not. The logistic and linear regression analyses were used to determine whether the mutation was a standalone predictive predictor of the duration of fever and hospital length of stay. RESULTS: First, no patients had a fever for ≥ 7 days after macrolide treatment. But length of stay and hormone concentration were significantly different between the two groups (P < 0.05). There were also no statistical association between the mutation and the duration of fever and hospital length of stay. CONCLUSION: Macrolides can be administered to MPP children carrying a macrolide-resistant mutation. tNGS can be seen as a front-line diagnostic in MPP.
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Antibacterianos , Farmacorresistencia Bacteriana , Macrólidos , Mutación , Mycoplasma pneumoniae , Neumonía por Mycoplasma , ARN Ribosómico 23S , Humanos , Neumonía por Mycoplasma/tratamiento farmacológico , Neumonía por Mycoplasma/microbiología , Macrólidos/uso terapéutico , Macrólidos/farmacología , Mycoplasma pneumoniae/genética , Mycoplasma pneumoniae/efectos de los fármacos , Femenino , Masculino , Antibacterianos/uso terapéutico , Antibacterianos/farmacología , Preescolar , Niño , Farmacorresistencia Bacteriana/genética , Estudios Retrospectivos , ARN Ribosómico 23S/genética , Lactante , Tiempo de Internación , Resultado del Tratamiento , Secuenciación de Nucleótidos de Alto RendimientoRESUMEN
Hydrogen atoms can enter into metallic materials through penetration and diffusion, leading to the degradation of the mechanical properties of the materials, and the application of hydrogen barrier coatings is an effective means to alleviate this problem. Zirconia coatings (ZrO2) have been widely studied as a common hydrogen barrier coating, but zirconia undergoes a crystalline transition with temperature change, which can lead to volumetric changes in the coating and thus cause problems such as cracking and peeling of the coating. In this work, ZrO2 coating was prepared on a Q235 matrix using a sol-gel method, while yttria-stabilized zirconia (YSZ) coatings with different contents of rare earth elements were prepared in order to alleviate a series of problems caused by the crystal form transformation of ZrO2. The coating performances were evaluated by the electrochemical hydrogen penetration test, pencil hardness test, scratch test, and high-temperature oxidation test. The results show that yttrium can improve the stability of the high-temperature phase of ZrO2, alleviating the cracking problem of the coating due to the volume change triggered by the crystalline transition; improve the consistency of the coating; and refine the grain size of the oxide. The performance of YSZ coating was strongly influenced by the yttria doping mass, and the coating with 10 wt% yttria doping had the best hydrogen barrier performance, the best antioxidant performance, and the largest adhesion. Compared with the matrix, the steady-state hydrogen current density of the YSZ coating decreased by 72.3%, the antioxidant performance was improved by 65.8%, and the ZrO2 coating hardness and adhesion levels were B and 4B, respectively, while YSZ coating hardness and adhesion were upgraded to 2H and 5B. With the further increase in yttrium doping mass, the hardness of the coating continued to improve, but the defects of the coating increased, resulting in a decrease in the hydrogen barrier performance, antioxidant performance, and adhesion. In this work, the various performances of ZrO2 coating were significantly improved by doping with the rare earth element, which provides a reference for further development and application of oxide coatings.
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BACKGROUND: Quercetin is a flavonol compound widely distributed in plants that possesses diverse biological properties, including antioxidative, anti-inflammatory, anticancer, neuroprotective and senescent cell-clearing activities. It has been shown to effectively alleviate neurodegenerative diseases and enhance cognitive functions in various models. The immune system has been implicated in the regulation of brain function and cognitive abilities. However, it remains unclear whether quercetin enhances cognitive functions by interacting with the immune system. RESULTS: In this study, middle-aged female mice were administered quercetin via tail vein injection. Quercetin increased the proportion of NK cells, without affecting T or B cells, and improved cognitive performance. Depletion of NK cells significantly reduces cognitive ability in mice. RNA-seq analysis revealed that quercetin modulated the RNA profile of hippocampal tissues in aging animals towards a more youthful state. In vitro, quercetin significantly inhibited the differentiation of Lin-CD117+ hematopoietic stem cells into NK cells. Furthermore, quercetin promoted the proportion and maturation of NK cells by binding to the MYH9 protein. CONCLUSIONS: In summary, our findings suggest that quercetin promotes the proportion and maturation of NK cells by binding to the MYH9 protein, thereby improving cognitive performance in middle-aged mice.
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Fumonisin (FB) is a pervasive hazardous substance in the environment, presenting significant threats to human health and ecological systems. Thus, the selective and sensitive detection of fumonisin B1 (FB1) is crucial due to its high toxicity and wide distribution in corn, oats, and related products. In this work, we developed a novel and versatile fluorescent aptasensor by combining enzyme-assisted dual recycling amplification with 2D δ-FeOOH-NH2 nanosheets for the determination of FB1. The established CRISPR/Cas12a system was activated by using activator DNA (aDNA), which was released via a T7 exonuclease-assisted recycling reaction. Additionally, the activated Cas12a protein was utilized for non-specifically cleavage of the FAM-labeled single-stranded DNA (ssDNA-FAM) anchored on δ-FeOOH-NH2 nanosheets. The pre-quenched fluorescence signal was restored due to the desorption of the cleaved ssDNA-FAM. Due to the utilization of this T7 exonuclease-Cas12a-δ-FeOOH-NH2 aptasensor for signal amplification, the detection range of FB1 was expanded from 1 pg/mL to 100 ng/mL, with a limit of detection (LOD) as low as 0.45 pg/mL. This study not only provides novel insights into the development of fluorescence biosensors based on 2D nanomaterials combined with CRISPR/Cas12a, but also exhibits remarkable applicability in detecting other significant targets.
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Técnicas Biosensibles , Fumonisinas , Humanos , ADN de Cadena Simple , Colorantes Fluorescentes , Sistemas CRISPR-Cas , Límite de DetecciónRESUMEN
A simple and portable paper-based analytical device was developed for visual and semiquantitative detection of ferric ion in real samples using green emitting carbon dots (CDs), which were prepared via microwave method using sodium citrate, urea and sodium hydroxide as raw materials and then loaded on the surface of paper substrate. When Fe3+ exists, the green fluorescence of CDs was quenched and significant color change from green to dark blue were observed, resulting the visual detection of Fe3+ with a minimum distinguishable concentration of 100 µM. By analyzing the intensity changes of green channels of test paper with the help of smartphone, the semiquantitative detection was realized within the range of 100 µM to 1200 µM. The proposed paper-based analytical devices have great application prospects in on site detection of Fe3+ in real samples.
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Developing non-noble-metal electrocatalysts for hydrogen evolution reactions with high activity and stability is the key issue in green hydrogen generation based on electrolytic water splitting. It has been recognized that the stacking of large CoP particles limits the intrinsic activity of as-synthesized CoP catalyst for hydrogen evolution reaction. In the present study, N-MoxC/CoP-0.5 with excellent electrocatalytic activity for hydrogen evolution reaction was prepared using N-MoxC as decoration. A reasonable overpotential of 106 mV (at 10 mA cm-2) and a Tafel slope of 59 mV dec-1in 1.0 M KOH solution was achieved with N-MoxC/CoP-0.5 electrocatalyst, which exhibits superior activity even after working for 37 h. Uniformly distributed ultrafine nanoclusters of the N-MoxC/CoP-0.5 hybrids could provide sufficient interfaces for enhanced charge transfer. The effective capacity of the hydrogen evolution reaction could be preserved in the complex, and the enlarged electrocatalytic surface area could be expected to offer more active sites for the reaction.
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AIMS: There has been an increasing tendency to abandon crop cultivation and farming in old Lycium barbarum (wolfberry) stands to allow for natural restoration. However, little research has been dedicated to deciphering how soil quality changes in L. barbarum fields following abandonment from a physicochemical and microbiological perspective. Here we assessed the effects of farmland abandonment on anthropogenic-alluvial soil microbiota and contaminant residues in L. barbarum fields in Ningxia, China. METHODS AND RESULTS: Soil microbiota, heavy metal, and neonicotinoid pesticide profiles in L. barbarum fields abandoned for one to four years were characterized. Microbial community analysis was performed by high-throughput sequencing of the bacterial 16S ribosomal RNA genes and the fungal nuclear ribosomal internal transcribed spacer region. Soil bacterial diversity increased from before abandonment to year three after abandonment, and fungal diversity peaked in year one after abandonment. Enrichment of potentially beneficial taxa (e.g. Limnobacter, Cavicella) as well as pathogenic taxa (e.g. Ilyonectria) was observed in the abandoned field soils, along with depletion of other taxa (e.g. Planococcus, Bipolaris). Soil copper, zinc, cadmium, imidacloprid, and acetamiprid concentrations all decreased with increasing time since abandonment and had varied correlations with soil quality, microbial diversity, and the relative abundances of major phyla. Soil available phosphorus, nitrate-nitrogen, and pH were the key factors shaping bacterial communities. The structuring of fungal communities was strongly influenced by soil pH, available phosphorus, and available nitrogen contents. CONCLUSIONS: There were positive consequences of farmland abandonment in L. barbarum fields, such as optimized microbial community structure, reduced heavy metal accumulation, and enhanced pesticide degradation.
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Lycium , Microbiota , Granjas , Suelo , AgriculturaRESUMEN
Both heavy metals and antibiotics exert selection pressure on bacterial resistance, and as they are commonly co-contaminated in the environment, they may play a larger role in bacterial resistance. This study examined how breeding cycles affect antibiotic resistance genes (ARGs) in chicken manure and the surrounding topsoils at 20, 50, 100, 200, and 300 m from twelve typical laying hen farms in the Ningxia Hui Autonomous Region of northwest China. Six antibiotics, seven heavy metals, ten mobile genetic elements (MGEs), and microbial community affected the ARGs profile in chicken dung and soil samples. Tetracycline antibiotic residues were prevalent in chicken manure, as were relatively high content of aureomycin during each culture period. Zinc (Zn) content was highest among the seven heavy metals in chicken feces. Chicken dung also enriched aminoglycosides, MLSB, and tetracycline ARGs, notably during brooding and high production. The farm had a minimal influence on antibiotics in the surrounding soil, but its effect on ARGs and MGEs closer to the farm (50 m) was stronger, and several ARGs and MGEs increased with distance. Manure microbial composition differed dramatically throughout breeding cycles and sampling distances. ARGs were more strongly related with antibiotics and heavy metals in manure than soil, whereas MGEs were the reverse. Antibiotics, heavy metals, MGEs, and bacteria in manure accounted 12.28%, 22.25%, 0.74%, and 0.19% of ARGs composition variance, respectively, according to RDA and VPA. Bacteria (2.89%) and MGEs (2.82%) only affected soil ARGs composition. These findings showed that heavy metals and antibiotics are the main factors affecting faecal ARGs and bacteria and MGEs soil ARGs. This paper includes antibiotic resistance data for large-scale laying hen husbandry in northwest China and a theoretical framework for decreasing antibiotic resistance.
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Clortetraciclina , Metales Pesados , Animales , Femenino , Antibacterianos/farmacología , Pollos/genética , Estiércol/microbiología , Suelo/química , Genes Bacterianos , Metales Pesados/análisis , Farmacorresistencia Microbiana/genética , Bacterias/genética , Microbiología del SueloRESUMEN
Dual-emissive fluorescent carbon dots (CDs) were prepared through the solvothermal method with citric acid and urea as raw materials and dimethylformamide as the solvent. Two emission peaks were observed at 465 nm and 630 nm. Hg2+ could selectively quench the fluorescence at 630 nm, but the fluorescence intensity at 465 nm was less affected. Accordingly, a ratiometric fluorescence sensor for Hg2+ detection was developed, with a linear detection range of 0.5-40 µM and a limit of detection (LOD) of 37 nM. The dual-emissive CDs were loaded on the surface of the filter paper to fabricate Hg2+ detection test paper. The color of the test paper could be changed from pink purple to blue by the addition of Hg2+, and thus the qualitative and quantitative detection of Hg2+ could be realized. The concentration distinguishable by the naked eye reached 50 µM, and the quantitative detection range was 5-10,000 µM. This method shows excellent selectivity for Hg2+ and can be used to detect Hg2+ in real water samples, providing a highly potential sensing platform for rapid on-site detection of mercury ions.
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Cardiac malignancies in children are extremely rare and they with hypereosinophilia are rather relatively uncommon. The majority of individuals may survive over the long term even with heart tumors provided they don't have any significant symptoms and their hemodynamics are unaffected. But we should nevertheless be aware of them, especially when they are coupled with persistent hypereosinophilia and the development of a hemodynamic anomaly. The case of a malignant heart tumor with hypereosinophilia in a 13-year-old girl is presented in this paper. She exhibited an echocardiographic deficit and a heart murmur. Additionally, it was difficult to treat her hypereosinophilia. Nevertheless, it was resolved the day after the operation. We presume that there is a certain relationship between them. This study gives clinicians a wide range of options for analyzing the connections between malignancy and hypereosinophilia.
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Eosinofilia , Neoplasias Cardíacas , Neoplasias del Mediastino , Sarcoma , Neoplasias de los Tejidos Blandos , Neoplasias del Timo , Humanos , Niño , Femenino , Adolescente , Neoplasias Cardíacas/complicaciones , Neoplasias Cardíacas/diagnóstico , Neoplasias Cardíacas/cirugíaRESUMEN
Currently, numerous thermal comfort models have been proposed; however, research on the combination of different models is lacking. This study aims to predict the overall thermal sensation (OTS*) and thermal comfort (OTC*) with different model combinations under hot and cold step changes. Three cold- and hot-shock processes are designed in the climate chamber. Accordingly, the skin temperature, thermal sensation, and thermal comfort votes of 16 participants are collected. The impacts of winter hot and cold step changes on subjective votes and skin temperatures are evaluated. Further, the OTS* and OTC* values are calculated, and their accuracy under different model combinations is analyzed. The results reveal that thermal sensation changes in human body exhibit distinct asymmetry under the cold and hot step-changes, except for the cycle of "15-30-15 °C" (I15). The parts farther from the core area become more asymmetrical after the step changes. The single models exhibit the highest accuracy in different model combinations. The combined form of a single model is recommended for thermal sensation or comfort prediction.
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Frío , Sensación Térmica , Humanos , Estaciones del Año , Clima , Temperatura Cutánea , Temperatura , CalorRESUMEN
Temperature step change is the typical transient thermal environment. The purpose of this study was to explore the association of subjective and objective parameters in a step-change environment, including thermal sensation vote (TSV), thermal comfort vote (TCV), mean skin temperature (MST) and endogenous dopamine (DA). Three temperature step changes defined as I3 (15 °C-18 °C to 15 °C), I9 (15 °C-24 °C to 15 °C) and I15 (15 °C-30 °C to 15 °C) were designed for this experiment. Eight male and eight female healthy subjects who participated in the experiment reported thermal perception (TSV and TCV). Skin temperatures of six body parts and DA were measured. Results show that the inverted U-shaped in TSV and TCV was deviated by seasonal factors of the experiment. The deviation direction of TSV in winter was to the warm sensation side, which was opposite to the inherent cold and hot impression of people in winter and summer. The association between dimensionless dopamine (DA*), TSV and MST were described as follows: DA* was the U-shaped change with exposure times when MST was not greater than 31 °C, and TSV was at -2 and -1, and DA* increased with exposure times when MST was greater than 31 °C, and TSV was at 0, 1 and 2. The changes in the body heat storage and autonomous thermal regulation under temperature step changes may potentially be related to the concentration of DA. The human state on thermal nonequilibrium and stronger thermal regulation would correspond to a higher concentration of DA. This work is conducive to exploring the human regulation mechanism in a transient environment.
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Dopamina , Temperatura Cutánea , Humanos , Masculino , Femenino , Estaciones del Año , Frío , Calor , Sensación Térmica/fisiología , TemperaturaRESUMEN
Walnut oil is extracted from walnut kernels (Juglans regia Linne) or iron walnut kernels (Juhlans sigillata Dode). The percentage of oil in walnuts is 52%-70%. The main constituents in oil are fatty acids, phenols, sterols, squalene, melatonin, vitamins, and minerals. Many extraction methods such as supercritical carbon dioxide extraction, maceration, modified "bligh and dyer extraction," aqueous enzymatic extraction, ultrasonic extraction, soxhlet extraction, and cold-press extraction methods are reported in the literature. Walnut oil showed anti-inflammatory, antitumor, antioxidant, immunomodulatory, neuroprotective, cardioprotective, antidiabetic, and antihyperlipidemic activities. The reported data in the literature suggest that walnut oil has many health benefits. This review summarizes the extraction methods, bioactive constituents, health benefits, and pharmacological actions of walnut oil. PRACTICAL APPLICATIONS: Walnut oil is a natural vegetable oil of significant importance due to their nutritional, and intelligence-boosting benefits. Several factors, including the processing parameters and the phytochemical profile, affect walnut oil products' flavor and color. In addition, storage environment of walnut oil can also affect walnut oil quality. Apart from the predominant ingredient fatty acids, the chemical composition of walnut oil comprises phenols, sterols, squalene, melatonin, vitamins, and minerals. These bioactive compounds are of potential value owing to their health-promoting benefits, including antioxidant, antitumor, and cholesterol-lowering effects. Many chemical constituents were isolated from walnut oil; however, all the compounds are not explored for their possible medicinal value. Thus, clinical studies, exploration of the therapeutic potential and the molecular mechanisms of all the compounds, and development of convenient dosage forms either for therapeutic or functional food purposes are warranted.
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Juglans , Melatonina , Juglans/química , Antioxidantes/química , Escualeno , Fenoles/análisis , Minerales , Vitaminas , Vitamina A , Vitamina K , Esteroles , Ácidos GrasosRESUMEN
BACKGROUND: The goal of this meta-analysis is to evaluate the effects of exercise training on long-term health and cardiorespiratory fitness in participants with CHD after surgery and to investigate the optimal type of exercise training for post-operative patients and how to improve adherence to it. METHODS: We searched the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, and Web of Science from the date of the inception of the database through August 2021. RESULTS: Altogether, 1424 records were identified in the literature search. Studies evaluating outcomes between exercise training and usual care among post-operative patients with CHD were included. The assessed outcomes were quality of life and cardiorespiratory fitness. We analysed heterogeneity by using the I2 statistic and evaluated the evidence quality according to the recommendation by the Cochrane Collaboration. Nine randomised controlled trials were included. The evidence showed that exercise interventions increased peak oxygen consumption (mean difference = 2.29 [95% CI 0.43, 4.15]; p = 0.02, I2 = 0%). However, no differences in scores of health-related quality of life and pulmonary function were observed between the experimental and control groups. CONCLUSIONS: In conclusion, participation in a physical exercise training programme was safe and improved fitness in patients after surgery for CHD. We recommend that post-operative patients with CHD participate in physical exercise training. Additional research is needed to study the various forms of exercise training and their impact on quality of life.
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Ejercicio Físico , Calidad de Vida , Humanos , Terapia por Ejercicio , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
Atractylodes macrocephala Koidz (AM), traditional Chinese medicine (TCM) with many medicinal values, has a long usage history in China and other oriental countries. The phytochemical investigation revealed the presence of volatile oils, polysaccharides, lactones, flavonoids, and others. The polysaccharides from AM are important medicinal components, mainly composed of glucose (Glc), galactose (Gal), rhamnose (Rha), arabinose (Ara), mannose (Man), galacturonic acid (GalA) and xylose (Xyl). It also showed valuable bioactivities, such as immunomodulatory, antitumour, gastroprotective and intestinal health-promoting, hepatoprotective, hypoglycaemic as well as other activities. At the same time, based on its special structure and pharmacological activity, it can also be used as immune adjuvant, natural plant supplement and vaccine adjuvant. The aim of this review is to summarize and critically analyze up-to-data on the chemical compositions, biological activities and applications of polysaccharide from AM based on scientific literatures in recent years.
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Poria cocos polysaccharide (PCP) is one of the main active components of Poria cocos that is extensively used in the world. PCP can be divided into intro-polysaccharides and exopolysaccharides. PCP is mainly composed of glucose, galactose and mannose. There are many methods to exact PCP, and methods can affect its yield. PCP and its derivatives exhibit diverse biological functions such as antitumour, antioxidant, anti-inflammatory, immune-regulatory, hepatoprotective, etc. There is the potential application of PCP as drug carriers. The review provides a comprehensive summary of the latest extraction and purification methods of PCP, its chemistry, synthesis of PCP derivates, their pharmacological activities and their applications as drug carriers. This review provides comprehensive information on PCP, which can be used as the basis for further research on PCP and its derivates.
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Poria , Wolfiporia , Antiinflamatorios/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Carbohidratos de la Dieta , Portadores de Fármacos , Polisacáridos/química , Polisacáridos/farmacología , Poria/química , Wolfiporia/químicaRESUMEN
An ultrasensitive fluorescence assay strategy on the basis of carbon dots (CDs) and cDNA-modified gold nanoparticles (AuNP-cDNA) was developed for the determination of microRNA-21 (miRNA-21) via internal filtering effect (IFE). Positively charged CDs (PEI-CDs), the fluorophores in IFE, were synthesized via a hydrothermal method using polyethyleneimine (PEI) as surface ligand. The maximum emission wavelength is located at 500 nm under the excitation of 410 nm. AuNPs, the absorbers, were modified with single-stranded DNA (cDNA), which is completely complementary to miRNA-21. The fluorescence of PEI-CDs is quenched due to the assembly of PEI-CDs and AuNPs-cDNA. In the presence of miRNA-21, the hybridization between miRNA-21 and cDNA causes the release of PEI-CDs and the recovery of fluorescence intensity.The fluorescence recovery degree is linearly correlated with the logarithm of miRNA-21 concentration in the range of 1-1000 fM. This method can be applied to determine miRNA-21 in real serum samples, and the detection results are in well agreement with those of qRT-PCR. The determination of miRNA-21 spiked into diluted human serum samples displays satisfactory recovery within the range 88.44-112.7%, which confirmed the reliability for miRNAs detection in real samples.
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Nanopartículas del Metal , MicroARNs , Puntos Cuánticos , Carbono , ADN/análisis , ADN/genética , ADN Complementario , Oro , Humanos , Límite de Detección , MicroARNs/análisis , Polietileneimina , Reproducibilidad de los ResultadosRESUMEN
Bioremediation, which has several advantages over traditional methods, represents an alternative means of dealing with heavy metal pollution. We screened for microorganisms showing heavy metal tolerance in polluted mangrove soils. A novel yeast, Geotrichum sp. CS-67, was discovered and tested for tolerance of Cu2+, Zn2+, and Ni2+. Zn2+ was the most efficiently sequestered by Geotrichum sp. CS-67 followed by Ni2+ and Cu2+. Zn2+ and Ni2+ were actively taken up into the cell, while Cu2+ was adsorbed to the cell wall. We used RNA-Seq to show that a large number of genes involved in the physiological and biochemical processing of heavy metals were differentially expressed in this yeast when it was subjected to Zn2+ and Ni2+ stress. From this panel, we selected the SED1, GDI1 and ZRT1 genes for validation by qRT-PCR and discovered that, during Zn2+ and Ni2+ stress, SED1 and GDI1 were upregulated, while ZRT1 was downregulated, which was consistent with the RNA-Seq results and the biochemical function of these genes. In conclusion, the novel yeast Geotrichum sp. CS-67 has a marked ability to accumulate heavy metal ions, making it of great interest as a possible microbial agent for heavy metal pollution remediation in the future.