•A novel method for the sensing of adenosine triphosphate was developed.•The detection was based on S1 nuclease, FAM-labeled ssDNA and graphene oxide.•The method was applied to the evaluation of meat ...freshness.
A novel simple, sensitive and reliable sensor based on S1 nuclease, FAM-labeled ssDNA (DNA-F) and graphene oxide (GO) was developed for detecting adenosine triphosphate (ATP) and evaluating the freshness of meat (beef) samples. With S1 nuclease as the cleaver of DNA-F and ATP as the inhibitor of S1 nuclease, the fluorescence of DNA-F could be obviously quenched by GO, which exhibits the fluorescence of system gradually decrease as the increasing ATP concentration. Under the optimal conditions, a linear correlation between the fluorescence and the ATP concentration from 20 μM to 3500 μM is obtained with a detection limit of 3.2 μM. Furthermore, the proposed ATP detection method was applied to the ATP detection in microorganisms in meat samples, which acquired the satisfying results, respectively.
The reactivity of diazadiphosphapentalene 1 towards various substrates was investigated. Reaction of 1 with ammonia–borane resulted in transfer hydrogenolysis concomitantly with the cleavage of a P−N ...bond. By treatment of 1 with 2,2,6,6‐tetramethylpiperidine‐1‐oxyl (TEMPO), oxidation took place at one of the phosphorus atoms of 1, and a PV/PIII mixed‐valence derivative was isolated. At the same time, it was demonstrated that only one of the phosphorus atoms in 1 behaves as an electron donor for electrophiles and Lewis acids. The former afforded an intramolecularly coordinated phosphine‐phosphenium species, whereas the latter demonstrates the ligand property of 1. UV irradiation induced rearrangement of 1 into another example of another diazadiphosphapentalene.
Reactivity series: Reactivity of diazadiphosphapentalene 1 towards various substrates was investigated. Activation of ammonia–borane by 1 proceeded concomitantly with the cleavage of the P−N bond in 1, while electrophiles and Lewis acids readily coordinated to the P atom between two carbon atoms in 1 (see scheme). Under irradiation with a Hg(Xe) lamp, photoisomerization of 1 occurred to afford a new diazadiphosphapentalene derivative.
ABSTRACT
Early‐stage photoaging is characterized by skin laxity and wrinkling, which are mainly attributable to the ultraviolet (UV) irradiation‐mediated imbalance between matrix metalloproteinase ...(MMP) production and collagen degradation. Injectable platelet‐rich fibrin (i‐PRF) is a novel blood concentrate with potential effects on photoaging. Over the past few decades, platelet‐rich plasma (PRP) has been widely researched and used in different clinical fields as a first‐generation platelet concentrate. The aim of this study was to compare the antiphotoaging effects of i‐PRF in UVA‐irradiated human dermal fibroblasts with those of PRP by examining cell proliferation, migration and apoptosis, ROS generation, MMP‐1 and collagen I levels. The activation of the TGF‐β/Smad signaling pathway by i‐PRF and PRP was also investigated using western blotting. The results showed that i‐PRF was more effective than PRP in promoting cell proliferation and migration. Moreover, i‐PRF reduced ROS generation and cell apoptosis more effectively than PRP. With respect to the mechanism of collagen I upregulation, stronger stimulation of the TGF‐β/Smad signaling pathway and greater suppression of MMP‐1 expression were achieved by i‐PRF than by PRP. Our results suggest that i‐PRF can be a promising substitute for PRP in alleviating UVA‐induced photoaging and should be explored further for its anti‐photoaging properties.
In comparison to PRP, i‐PRF has a stronger antiphotoaging effect on UVA‐irradiated HDFs through its promotion of cell proliferation and cell migration, reduction in ROS generation and cell apoptosis, alleviation of collagen degradation and stimulation of collagen synthesis. In addition, compared to PRP, i‐PRF was found to more potently activate the TGF‐β/Smad pathway. Therefore, i‐PRF may be a promising new therapeutic candidate for photoaging.
High-efficient multispectral electromagnetic-interference (EMI) shielding membranes, with robust resistance against broad temperature range and good thermal isolating capacity, are highly desirable ...to prevent human being and portable sensitive electrical devices from both outside detrimental electromagnetic irradiation (interference) threaten and heat under harsh conditions, but still a challenge to be realized. Herein, an effective route has been demonstrated to address this challenge by constructing ternary polyacrylonitrile/W18O49/Ag composite nanofibrous membrane via electrospinning and post treatment. Prompted by the high electrical conductivity (∼30400 S cm−1) and multi-porous structures, our membrane exhibits outstanding EMI shielding effectiveness (SE) against multi-bands: (i) highest SE was ∼100.9 dB from 8 to 26.5 GHz (thickness: 0.11 mm); (ii) low emissivity (from 0.26 to 0.6) over whole-infrared bands (15 ∼ 150 THz; thickness: 0.11 mm); (iii) 99% X-ray attenuation of 30 keV (6.8–22.7 EHz; thickness: 1.92 mm). Moreover, our membrane also possesses good thermal insulating capacity to inhibit the heat, caused by the incident EM waves irradiation or outer hot environment, to protect the substrates. Most importantly, robust temperature tolerance has been also realized based on our membrane over broad temperature range (from −196 °C to 385 °C). These outstanding functions make our membrane hold great potential in constructing EMI layer for both human beings and sensitive electronic devices under harsh temperature.
Ternary PAN/W18O49/Ag nanofibrous membrane has been designed to realize the high-efficient and multi-band electromagnetic-interference shielding protective layer with unexpected broad temperature tolerance and good thermal isolating capacity. Display omitted
•A ternary PAN/W18O49/Ag nanofibrous membrane (NM) has been fabricated for multispectral EMI shielding.•The as-prepared NM exhibits robust EMI SE (highest SE: 100.9 dB; thickness: 0.11 mm) in the microwave band (8–26.5 GHz).•Emissivity (from 0.26 to 0.60; thickness: 0.11 mm) in IR bands and 99% (thickness: 1.92 mm) X-ray attenuation of 30 keV.•Robust temperature tolerance (from −196 °C to 385 °C) has been realized.
Fusarium solani-induced quality deterioration in stored sweet potato is poorly characterized and understood. This study examined the effects of F. solani infection in Xinxiang sweet potato roots ...during storage. The results showed that while there were no external symptoms following F. solani infection, upon cutting the roots, the cut surface of the infected root rapidly turned black, whereas the untreated control roots remained unaffected. The metabolites and transcriptive differences between F. solani-infected and control sweet potato roots were investigated with high-performance liquid chromatography, metabolomic analysis, and an Illumina Novaseq platform. The results showed that levels of the toxic ipomeamarone accumulated as high as 2.36 mg/kg DW in tissue after F. solani inoculation and 6 days storage at 28 °C, where the control tissue sample did not accumulate any ipomeamarone. Metabolomic analysis showed that isochlorogenic acid and l-tyrosine significantly increased in the infected tissue and associated with the darkening cut surface of the infected sweet potato. In transcriptomic analysis, a total of 13, 14, and 6 key genes in ipomeamarone, isochlorogenic acid, and l-tyrosine biosynthesis pathways, respectively, were identified. A conceptual model elucidating the physiological and molecular mechanism of F. solani-induced quality deterioration in sweet potato is proposed.
Circulating cell-free DNA (cfDNA) is a promising biomarker of liquid biopsy, but it still faces some difficulties in achieving sensitive and convenient detection. Herein, an Ω-shaped fiber optic ...localized surface plasmon resonance (FO-LSPR) biosensor based on hybridization chain reaction (HCR) coupled with gold nanoparticles (AuNPs) was developed, and applied in simple and sensitive detection of cfDNA. Specifically, one-base mismatch was designed in HCR hairpins (H1 and H2) to obtain high reaction efficiency, and AuNPs was introduced onto H1 through poly-adenine to construct HCR coupled with AuNPs strategy. Meanwhile, target cfDNA was designed into two domains: one could trigger HCR to generate dsDNA concatemer carrying numerous AuNPs, and the other could hybridize with capture DNA on the surface of Ω-shaped fiber optic (FO) probes. Thus, the presence of target cfDNA would initiate HCR, and bring the formed dsDNA concatemer and AuNPs to approach the probe surface, resulting in dramatically amplified LSPR signal. Besides, HCR required simple isothermal and enzyme-free condition, and Ω-shaped FO probe with high refractive index sensitivity just needed to be immersed into HCR solution directly for signal monitoring. Benefiting from the synergetic amplification of mismatched HCR and AuNPs, the proposed biosensor exhibited high sensitivity with a limit of detection of 14.0 pM, and therefore could provide a potential strategy for biomedical analysis and disease diagnosis.
Circular RNA circSKA3 (spindle and kinetochore-related complex subunit 3) has been identified as a prognostic factor in ischemic stroke. The objective of this study was to investigate the association ...of circSKA3 with the risk of extracranial artery stenosis (ECAS) and plaque instability in patients with ischemic stroke. We constructed a competing endogenous RNA (ceRNA) network regulated by circSKA3 based on differentially expressed circRNAs and mRNAs between five patients and five controls. Gene Ontology (GO) analysis was performed on the 65 mRNAs within the network, revealing their primary involvement in inflammatory biological processes. A total of 284 ischemic stroke patients who underwent various imaging examinations were included for further analyses. Each 1 standard deviation increase in the log-transformed blood circSKA3 level was associated with a 56.3% increased risk of ECAS (
P
= 0.005) and a 142.1% increased risk of plaque instability (
P
= 0.005). Patients in the top tertile of circSKA3 had a 2.418-fold (
P
< 0.05) risk of ECAS compared to the reference group (
P
for trend = 0.02). CircSKA3 demonstrated a significant but limited ability to discriminate the presence of ECAS (AUC = 0.594,
P
= 0.015) and unstable carotid plaques (AUC = 0.647,
P
= 0.034). CircSKA3 improved the reclassification power for ECAS (NRI: 9.86%,
P
= 0.012; IDI: 2.97%,
P
= 0.007) and plaque instability (NRI: 36.73%,
P
= 0.008; IDI: 7.05%,
P
= 0.04) beyond conventional risk factors. CircSKA3 played an important role in the pathogenesis of ischemic stroke by influencing inflammatory biological processes. Increased circSKA3 was positively associated with the risk of ECAS and plaque instability among ischemic stroke patients.
Sensitive and selective protein detection based on the aptamer-controlled noncovalent porphyrin probe self-assembly is reported for the first time. Vascular endothelial growth factor (VEGF) is a ...predominant biomarker in cancer angiogenesis. In this work, a positively charged porphyrin probe, manganese(III) meso-tetrakis(N-methylpyridinum-4-yl)porphyrin (Mn–PyP), was prepared. Using it as a catalyst, a label-free chemiluminescence (CL) turn-on approach for sensitive VEGF detection is developed. Mn–PyP could catalyze the luminol CL reaction. The VEGF aptamer could induce aggregation of Mn–PyP. As a result, the Mn–PyP-catalyzed CL reaction is efficiently suppressed. Upon the addition of VEGF, the specific binding of VEGF to the aptamer weakens the interactions between the aptamer and Mn–PyP. The Mn–PyP monomers are released, and a turn-on CL signal is thus detected. Our method is quite sensitive; 50 pM of VEGF could be easily detected. It is also very selective against other proteins. Our assay provides an aptamer-based efficient way for protein quantification.
A novel flow-injection chemiluminescence (FI-CL) method for the determination of estrogens is proposed, based upon its enhancing effect on the CL reaction of luminol with hydrogen peroxide catalyzed ...by tetrasulfonated manganese phthalocyanine (MnTSPc) in alkaline solution. Under the selected experimental conditions, a linear relationship was obtained between the CL intensity and the concentration of estrone in the range of 1.0
×
10
−7 to 1.0
×
10
−6
mol/l, estradiol in the range of 9.0
×
10
−8 to 1.0
×
10
−6
mol/l and estriol in the range of 3.0
×
10
−7 to 2.0
×
10
−6
mol/l, respectively. The detection limits were 5.1
×
10
−8
mol/l for estrone, 7.2
×
10
−9
mol/l for estradiol and 6.5
×
10
−8
mol/l for estriol with a relative standard deviation of 2.8% for 5.0
×
10
−7
mol/l estrone, 2.4% for 1.0
×
10
−7
mol/l estradiol, and 3.1% for 7.0
×
10
−7
mol/l estriol (
n
=
11). This method has been applied to the determination of estrogen in pharmaceutical injections and tap water with satisfactory results.
Dipicolinic acid (DPA), as a biomarker for Bacillus anthracis, is highly toxic at trace levels. Rapid and on-site quantitative detection of DPA is essential for maintaining food safety and public ...health. This work develops a dual-channel self-calibrated fluorescence sensor constructed by the YVO4:Eu and Tb-β-diketone complex for rapid visual detection of DPA. This sensor exhibits high selectivity, fast response time, excellent detection sensitivity, and the detection limit is as low as 4.5 nM in the linear range of 0–16 μM. A smartphone APP and portable ultraviolet lamp can assemble a mobile fluorescence sensor for on-site analysis. Interestingly, adding Cu2+ ions can quench the fluorescence intensity of Tb3+. In contrast, the addition of cysteine can restore the fluorescence, allowing the accurate detection of Cu2+ ions and cysteine in environmental water and food samples. This work provides a portable sensor that facilitates real-time analysis of multiple targets in food and the environment.
Display omitted
•A self-calibrated YVO4:Eu@TTA-Si-Tb sensor.•The continuous detection of DPA, Cu2+ and Cys.•Smartphone-assisted mobile sensor for on-site rapid analysis.•Targets detection in environmental water and food samples.
