Quercetin promotes the proportion and maturation of NK cells by binding to MYH9 and improves cognitive functions in aged mice.

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.

Green fabrication of ultrafine N-MoxC/CoP hybrids for boosting electrocatalytic water reduction.

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.

Portable smartphone-assisted ratiometric fluorescent test paper based on one-pot synthesized dual emissive carbon dots for visualization and quantification of mercury ions.

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.

Effects of farmland abandonment on anthropogenic-alluvial soil microbiota and contaminant residues in Lycium barbarum fields.

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.

Effects of the coexistence of antibiotics and heavy metals on the fate of antibiotic resistance genes in chicken manure and surrounding soils.

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.

Overall thermal sensation and comfort prediction with different model combinations: Cold and hot step-change environments in winter.

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.

Association between thermal response and endogenous dopamine: Step-change environments in winter.

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.

A novel yeast strain Geotrichum sp. CS-67 capable of accumulating heavy metal ions.

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.

Impact of exercise training in patients after CHD surgery: a systematic review and meta-analysis of randomised controlled trials.

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.

Ultrasensitive fluorescence detection of microRNA through DNA-induced assembly of carbon dots on gold nanoparticles with no signal amplification strategy.

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.

Culture and in situ H2O2-mediated electrochemical study of cancer cells using three-dimensional scaffold based on graphene foam coated with Fe3O4 nanozyme.

For real-time evaluation of the cell behavior and function under in vivo-like 3D environment, the 3D functionalized scaffolds simultaneously integrate the function of 3D cell culture, and electrochemical sensing is a convincing candidate. Herein, Fe3O4 nanoparticles as the nanozyme (peroxide oxidase mimics) were modified on graphene foam scaffold to construct a 3D integrated platform. The platform displayed a wide linear range of 100 nM to 20 µM and a high sensitivity of 53.2 nA µM-1 toward detection of hydrogen peroxide (H2O2) under the working potential of + 0.6 V (vs. Ag/AgCl). The obtained 3D scaffold also displayed satisfactory selectivity toward the possible interferents that appeared in the cell culture environment. Furthermore, the cells still maintained high cell viability (almost 100%) after their growth and proliferation on the scaffold for 7 days. With the superior performance on cell culture and electrochemical monitoring, the functions on the 3D culture of MCF-7 or HeLa cells and in situ monitoring of cell-released H2O2 was easily achieved on this 3D platform, which show its great application prospects on further cancer-related disease diagnosis or drug screening. A nanozyme-based three-dimensional graphene scaffold was successfully constructed for cell culture and identification of cancer cells through in situ electrochemical monitoring of the cell-released H2O2.

A paper-supported sandwich immunosensor based on upconversion luminescence resonance energy transfer for the visual and quantitative determination of a cancer biomarker in human serum.

In this paper, a paper-supported analytical device based on a sandwich immunoreaction and luminescence resonance energy transfer (LRET) was reported for the visual and quantitative determination of a cancer biomarker, in which upconversion nanoparticles (UCNPs) were located on the surface of the paper as energy donors and gold nanoparticles (AuNPs) were used as energy acceptors. Upon the recognition of the cancer biomarker by two rationally selected antibodies, the upconversion luminescence was quenched by the AuNPs in a biomarker concentration-dependent manner. As a model target, CEA was detected using this immunosensor, and a linear relationship within 0.5-30 ng mL-1 was obtained in buffer solution, with a detection limit of 0.21 ng mL-1. The immunosensor was also applicable in 20-fold diluted human serum with a linear range of 0.5-30 ng mL-1 and a detection limit of 0.36 ng mL-1. This technique also realized the qualitative judgment of the critical concentration of CEA in serum samples by the naked eye. This approach displays great application potential for point-of-care testing in clinical applications, as well as the potentiality to be extended to other kinds of disease-related biomolecules.

Correction: A paper-supported sandwich immunosensor based on upconversion luminescence resonance energy transfer for the visual and quantitative determination of a cancer biomarker in human serum.

Correction for 'A paper-supported sandwich immunosensor based on upconversion luminescence resonance energy transfer for the visual and quantitative determination of a cancer biomarker in human serum' by Mengyuan He et al., Analyst, 2020, 145, 4181-4187, DOI: .

Jannaschia marina sp. nov., isolated from the gut of a gastropod, Onchidium reevesii.

A taxonomic study was carried out on strain SHC163T, which was isolated from the gut of Onchidium reevesii. The bacterium was Gram-stain-negative, oxidase-positive, catalase-negative and rod-shaped. Growth was observed at salinities of 0-4.0 % NaCl and at temperatures of 15-35 °C. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain SHC163T belonged to the genus Jannaschia, with the highest sequence similarity to Jannaschia seosinensis CL-SP26T (97.9%), followed by Jannaschia faecimaris DSM 100420T (97.8 %), Jannaschia rubra CECT 5088T (97.5%) and eight species of the genus Jannaschia (94.7-97.1 %). The average amino acid identity, average nucleotide identity and the digital DNA-DNA hybridization estimate values between strain SHC163T and the type strains of the genus Jannaschia were 64.33-79.78 %, 71.0-78.4 % and 19.2-21.0%, respectively. The principal fatty acids (>5 %) were summed feature 8 (C18 : 1 ω7c/C18 : 1 ω6c, 56.5 %), C18 : 1 ω7c 11-methyl (23.1 %), C18 : 0 (8.7 %). The G+C content of the chromosomal DNA was 67.8 mol%. The respiratory quinone was determined to be Q-10 (100 %). The polar lipids were phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, an unidentified phospholipid, an unidentified aminolipid and aminophospholipid. The combined genotypic and phenotypic data show that strain SHC163T represents a novel species within the genus Jannaschia, for which the name Jannaschia marina sp. nov. is proposed, with the type strain SHC163T (=MCCC 1K04032T=KCTC 72524T).

Portable Upconversion Nanoparticles-Based Paper Device for Field Testing of Drug Abuse.

We report the first portable upconversion nanoparticles (UCNPs)-based paper device for road-side field testing of cocaine. Upon the recognition of cocaine by two pieces of rationally designed aptamer fragments, the luminescence of UCNPs immobilized on the paper is quenched by Au nanoparticles (AuNPs), which indicates the cocaine concentration. This device can give quantitative results in a short time with high sensitivity using only a smartphone as the apparatus. Moreover, this device is applicable in human saliva samples, and it also can be used to monitor the cocaine content change in blood samples. The results of this work demonstrate the prospect of developing UCNPs-based paper devices for field testing of drug abuse.

Yttria-Stabilized Zirconia Composite Coating as Barrier to Reduce Hydrogen Permeation into Steel.

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.

A novel fluorescent aptasensor for sensitive and selective detection of environmental toxins fumonisin B1 based on enzyme-assisted dual recycling amplification and 2D δ-FeOOH-NH2 nanosheets.

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.

Paper-based microfluidic device with upconversion fluorescence assay.

A paper-based microfluidic device with upconversion fluorescence assay (named as UC-µPAD) is proposed. The device is fabricated on a normal office printing sheet with a simple plotting method. Upconversion phosphors (UCPs) tagged with specific probes are spotted to the test zones on the µPAD, followed by the introduction of assay targets. Upconversion fluorescence measurements are directly conducted on the test zones after the completion of the probe-to-target reactions, without any post-treatments. The UC-µPAD features very easy fabrication and operation, simple and fast detection, low cost, and high sensitivity. UC-µPAD is a promising prospect for a clinical point-of-care test.

Cardiac endothelial sarcoma with hypereosinophilia of children: a case report.

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.

Semiquantitative and visual detection of ferric ions in real samples using a fluorescent paper-based analytical device constructed with green emitting carbon dots.

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.