A novel IgE epitope-specific antibodies-based sandwich ELISA for sensitive measurement of immunoreactivity changes of peanut allergen Ara h 2 in processed foods

BackgroundPeanut is an important source of dietary protein for human beings, but it is also recognized as one of the eight major food allergens. Binding of IgE antibodies to specific epitopes in peanut allergens plays important roles in initiating peanut-allergic reactions, and Ara h 2 is widely considered as the most potent peanut allergen and the best predictor of peanut allergy. Therefore, Ara h 2 IgE epitopes can serve as useful biomarkers for prediction of IgE-binding variations of Ara h 2 and peanut in foods. This study aimed to develop and validate an IgE epitope-specific antibodies (IgE-EsAbs)-based sandwich ELISA (sELISA) for detection of Ara h 2 and measurement of Ara h 2 IgE-immunoreactivity changes in foods.MethodsDEAE-Sepharose Fast Flow anion-exchange chromatography combining with SDS-PAGE gel extraction were applied to purify Ara h 2 from raw peanut. Hybridoma and epitope vaccine techniques were employed to generate a monoclonal antibody against a major IgE epitope of Ara h 2 and a polyclonal antibody against 12 IgE epitopes of Ara h 2, respectively. ELISA was carried out to evaluate the target binding and specificity of the generated IgE-EsAbs. Subsequently, IgE-EsAbs-based sELISA was developed to detect Ara h 2 and its allergenic residues in food samples. The IgE-binding capacity of Ara h 2 and peanut in foods was determined by competitive ELISA. The dose-effect relationship between the Ara h 2 IgE epitope content and Ara h 2 (or peanut) IgE-binding ability was further established to validate the reliability of the developed sELISA in measuring IgE-binding variations of Ara h 2 and peanut in foods.ResultsThe obtained Ara h 2 had a purity of 94.44%. Antibody characterization revealed that the IgE-EsAbs recognized the target IgE epitope(s) of Ara h 2 and exhibited high specificity. Accordingly, an IgE-EsAbs-based sELISA using these antibodies was able to detect Ara h 2 and its allergenic residues in food samples, with high sensitivity (a limit of detection of 0.98 ng/mL), accuracy (a mean bias of 0.88%), precision (relative standard deviation < 16.50%), specificity, and recovery (an average recovery of 98.28%). Moreover, the developed sELISA could predict IgE-binding variations of Ara h 2 and peanut in foods, as verified by using sera IgE derived from peanut-allergic individuals.ConclusionThis novel immunoassay could be a user-friendly method to monitor low level of Ara h 2 and to preliminary predict in vitro potential allergenicity of Ara h 2 and peanut in processed foods

FOXP2 regulates the proliferation, migration, and apoptosis of thyroid carcinoma cells via Wnt/β-catenin signaling pathway

Purpose: To determine the effect of Forkhead box P2 (FOXP2) on thyroid carcinoma cell growth and metastasis. Methods: Expression of FOXP2 in thyroid carcinoma cells was determined using quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and western blot. The 3-[4,5-dimethylthiazol-2-yl]- 2,5 diphenyl tetrazolium bromide (MTT) was applied to evaluate cell viability, while cell migration and invasion were assessed by wound healing and Transwell assays, respectively. Flow cytometry and western blot were conducted to investigate cell apoptosis. The underlying mechanisms were investigated using western blot assay. Results: Expression of FOXP2 was lower in primary thyroid carcinoma tissues than in normal tissues based on data from the TCGA database. Similarly, FOXP2 was lower in thyroid carcinoma cells at the mRNA and protein levels. Ectopic FOXP2 expression decreased cell viability, and retarded the migration and invasion of thyroid carcinoma cells. FOXP2 overexpression in thyroid carcinoma cells led to down-regulated expression of matrix metallopeptidase (MMP) 2, MMP 9, and proliferating cell nuclear antigen (PCNA), as well as induction of cell apoptosis. Moreover, FOXP2 overexpression resulted in enhanced Bax expression while Bcl-2 was reduced. Ectopic expression of FOXP2 decreased β-catenin, c-myc, and cyclin D1 in thyroid carcinoma cells. Conclusion: FOXP2 suppresses the proliferation and metastasis of thyroid carcinoma cells, but promotes apoptosis through suppression of the Wnt/β-catenin signaling pathway. These results provide an insight that may lead to the development of a novel potential therapeutic strategy for treating thyroid carcinoma

Development of Bidirectional Pulsed Power Supply and Its Effect on Copper Plating Effect of Printed Circuit Board Via-Filling

A bidirectional pulse power supply with continuously adjustable forward parameters 8 V/20 A and reverse parameters 20 V/50 A was designed using DSP (Digital Signal Processor), and the bidirectional pulse power supply was used to test copper plating on printed circuit boards with filled via holes. The effects of frequencies, pulse width ratios of forward and reverse currents, and current densities on the copper plating effect were investigated by the single variable method and were compared with DC copper plating. The experimental results showed that compared with DC power supply, the bidirectional pulse power supply had a better effect and a faster speed on via-filling copper plating, and can also reduce the use of additives, which is in line with green development. The parameters of the pulse affected the plating effect to varying degrees. In this solution system, the optimal parameters for bidirectional pulse plating are frequency 1 kHz, forward pulse current density 4 ASD (Ampere per Square Decimeter) with 50% duty cycle, and reverse pulse current density 16 ASD with 2.5% duty cycle

Toward Highly-Efficient and Accurate Services QoS Prediction via Machine Unlearning

Personalized Internet of Things (IoT) services prediction based on Quality-of-Service (QoS) is an indispensable technique for selecting appropriate services for each user. However, existing collaborative prediction models do not take into account the user’s authority to manage their own generated data. From the standpoint of users, the expectation is for models to eliminate the impact of their sensitive data to the greatest extent possible. Meanwhile, IoT service providers face the challenge of data contamination during service provision, which necessitates models to forget data quickly and accurately to restore performance. Furthermore, existing QoS prediction methods usually suffer from low model availability when handling unlearning requests by full retraining. This underscores the need to address security, availability, fidelity, privacy, and related issues, highlighting the urgency of unlearning. To solve the problem, we propose Context-Aware Data Driven Eraser (CADDEraser), a novel efficient machine unlearning framework for QoS prediction tasks. Firstly, we divide the training data into multiple shards to train submodels and obtain node embeddings by utilizing contextual information to derive graph embeddings. Then these embeddings are employed in a balanced clustering partition, ensuring the preservation of the QoS record between users and services. Finally, we use a concatenate aggregation method and stacking & attention-based aggregation methods to synthesize information from sub-models more efficiently. Experiments on large-scale datasets show that our CADDEraser framework not only improves efficiency but also enhances the accuracy of QoS prediction, achieving efficient unlearning and outperforms state-of-the-art unlearning approaches. Source codes are available at https://github.com/ZengYuXiang7/CADDEraser

Niclosamide alleviates pathological angiogenesis in hepatopulmonary syndrome by inhibiting

Objective To investigate the effects of niclosamide on S100A4 expression and pathological angiogenesis of hepatopulmonary syndrome (HPS) in rats. Methods Thirty male SD rats were randomly divided into control group (Sham group, n=6), common bile duct ligation (CBDL) group (n=18) and niclosamide treatment group (NIC group, n=6). The rats of the NIC group were gavaged with niclosamide suspension for 1 week since the first day of the third week after modelling, and the rats were dissected at the end of the fifth week to assess the pathological changes and disease progression of liver and lung tissues by HE and Masson staining. Immunofluorescence assay was used to detect the location and intensity of S100A4 and CD31 expression in the lung of rats. The expression of S100A4 at mRNA and protein levels was detected using qPCR and Western blotting. Pulmonary microvascular endothelial cells (PMVECs) were treated with small interfering RNA (siRNA) serum of HPS rats and nichosamide, respectively, and their effects on cell migration and tube-forming abilities were observed. Results Both mRNA and protein expression of S100A4 in lung tissue of the CBDL group rats were increased with disease progression, and the expression levels were higher than those in the Sham group (P < 0.000 1); The lung mRNA and protein levels of S100A4 were lower in the NIC group than the CBDL group at the 5th week, but still higher than those in the Sham group. After knockdown of S100A4 using siRNA in PMVECs, the migration and tube-forming abilities were reduced when compared with the NC group (P < 0.000 1). HE staining displayed that pulmonary pathological changes were milder in the NIC group than the CBDL group at the 5th week, while no such effect was found in the liver tissues. Masson staining showed that hepatic fibrosis was not obviously ameliorated in the NIC group. The migration and tube-forming abilities of the cells was significantly increased in the CBDL group after the 5 weeks of serum stimulation compared to the Sham rats, while niclosamide treatment reversed this phenomenon (P < 0.000 1). Conclusion S100A4 can accelerate the progression of HPS by promoting pulmonary micro-angiogenesis in HPS rats, and niclosamide inhibits the expression of S100A4 in the lung and thus delays the progression of HPS

Application of Evolutionary Encryption 2D Barcode Generation Technology in Agricultural Product Quality and Safety Traceability System

Two-dimensional (2D) barcode technology is an electronic tagging technology based on combination of computer and optical technology. It is an important way of information collection and input. 2D barcode technology has been widely used in various fields of logistics, production automation, and e-commerce, but it also has brought about a series of safety problems. Based on evolutionary encryption technology, this paper improved algorithm of traditional 2D barcode generation, to improve forgery-proof performance of 2D barcode. This algorithm is applied to agricultural products quality and safety traceability system and the results show that it is effective

Efficient Open-Set Recognition for Interference Signals Based on Convolutional Prototype Learning

Interference classification plays an important role in anti-jamming communication. Although the existing interference signal recognition methods based on deep learning have a higher accuracy than traditional methods, these have poor robustness while rejecting interference signals of unknown classes in interference open-set recognition (OSR). To ensure the classification accuracy of the known classes and the rejection rate of the unknown classes in interference OSR, we propose a new hollow convolution prototype learning (HCPL) in which the inner-dot-based cross-entropy loss (ICE) and the center loss are used to update prototypes to the periphery of the feature space so that the internal space is left for the unknown class samples, and the radius loss is used to reduce the impact of the prototype norm on the rejection rate of unknown classes. Then, a hybrid attention and feature reuse net (HAFRNet) for interference signal classification was designed, which contains a feature reuse structure and hybrid domain attention module (HDAM). A feature reuse structure is a simple DenseNet structure without a transition layer. An HDAM can recalibrate both time-wise and channel-wise feature responses by constructing a global attention matrix automatically. We also carried out simulation experiments on nine interference types, which include single-tone jamming, multitone jamming, periodic Gaussian pulse jamming, frequency hopping jamming, linear sweeping frequency jamming, second sweeping frequency jamming, BPSK modulation jamming, noise frequency modulation jamming and QPSK modulation jamming. The simulation results show that the proposed method has considerable classification accuracy of the known classes and rejection performance of the unknown classes. When the JNR is −10 dB, the classification accuracy of the known classes of the proposed method is 2–7% higher than other algorithms under different openness. When the openness is 0.030, the unknown class rejection performance plateau of the proposed method reaches 0.9883, while GCPL is 0.9403 and CG-Encoder is 0.9869; when the openness is 0.397, the proposed method is more than 0.89, while GCPL is 0.8102 and CG-Encoder is 0.9088. However, the rejection performance of unknown classes of CG-Encoder is much worse than that of the proposed method under low JNR. In addition, the proposed method requires less storage resources and has a lower computational complexity than CG-Encoder

Lightweight and High Impact Toughness PP/PET/POE Composite Foams Fabricated by In Situ Nanofibrillation and Microcellular Injection Molding

Polypropylene (PP) has become the most promising and candidate material for fabricating lightweight products. Microcellular injection molding (MIM) is a cost-effective technology for manufacturing porous plastic products. However, it is still challenging to fabricate high-performance PP microcellular components. Herein, we reported an efficient strategy to produce lightweight and high impact toughness foamed PP/polyethylene terephthalate (PET)/polyolefin-based elastomer (POE) components by combining in situ fibrillation (INF) and MIM technologies. First, the INF composite was prepared by integrating twin-screw compounding with melt spinning. SEM analysis showed PET nanofibrils with a diameter of 258 nm were achieved and distributed uniformly in the PP due to the POE’s inducing elaboration effect. Rheological and DSC analysis demonstrated PET nanofibrils pronouncedly improved PP’s viscoelasticity and crystal nucleation rate, respectively. Compared with PP foam, INF composite foam showed more stretched cells in the skin layer and refined spherical cells in the core layer. Due to the synergistic toughening effect of PET nanofibrils and POE elastic particles, the impact strength of INF composite foams was 295.3% higher than that of PP foam and 191.2% higher than that of melt-blended PP/PET foam. The results gathered in this study reveal potential applications for PP based INF composite foams in the manufacturing of lightweight automotive products with enhanced impact properties