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BACKGROUND: Soybean protein isolate hydrolysates (SPIHs) produced at high hydrostatic pressure have higher bioactivity. The aim of the study was to analyze the effects of different SPIH concentrations obtained under various pressures (0.1, 100, 200, and 300 MPa) on gelling properties, structural characteristics, and main forces of myofibrillar protein (MP) in MP‐SPIH plural gels. RESULTS: The MP‐SPIH plural gel with 3% SPIH produced under 200 MPa had the maximum gel strength (0.42 N) and water holding capacity (53.69%). A decline in thermal stability and a rise in storage modulus (G′) of MP‐SPIH plural gels were found with increased SPIH pressure and concentration. Additionally, the addition of SPIHs increased the amounts of α‐helix and β‐sheet, decreased random coil structural content of MP in MP‐SPIH plural gels, and facilitated the generation of a denser and uniform gels network. The molecular forces in MP‐SPIH plural gels were mainly hydrophobic interaction and hydrogen bond. CONCLUSION: This study showed that the interaction of MP with 3% SPIH obtained at 200 MPa improved the quality of plural gels. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

[Display omitted] • An ultra-sensitive SERS/colorimetric LFIA was constructed for nitrofurazone. • The nanoengineered signal tag has a high SBR ratio and anti-matrix interference. • The LODs of dual-mode LFIA for SEM were 20 pg/mL (Color) and 0.08 pg/mL (SERS). • The vLOD of dual-mode LFIA improved by a factor of 100 compared to AuNPs-LFIA. In this work, an ultra-sensitive lateral flow immunoassay (LFIA) with SERS/colorimetric dual signal mode was constructed for the detection of nitrofurazone metabolites, an antibiotic prohibited in animal-origin foods. Au@4-MBN@AgNRs nano-sandwich structural signal tag integrates the unique advantages of high signal-to-background ratio and anti-matrix interference through geometric control of SERS tag and nanoengineering adjustment of chemical composition. Under the optimal conditions, the detection limits of nitrofurazone metabolites by SERS/colorimetric dual-mode LFIA were 20 pg/mL (colorimetric mode) and 0.08 pg/mL (SERS mode). Excitingly, the vLOD of the colorimetric signal improved by a factor of 100 compared to Au NPs-based LFIA. In this study, the proposed dual-mode LFIA was successfully applied to the on-site real-time detection of honey, milk powder, and chicken. It is anticipated that with low background interference and anti-matrix interference output signal, our proposed dual-mode strategy can pave an innovative pathway for the fabrication of a powerful biosensor. [ABSTRACT FROM AUTHOR]

The single-signal colorimetric immunochromatography assay (ICA) is becoming increasing inadequate in dealing with current detection requirement, e.g., more flexible, accurate, and sensitive detection. Herein, by introducing tannic acid (TA) to exfoliate molybdenum disulfide (MoS 2) nanosheets and selecting anisotropic gold nanorods (AuNRs) as the nanocarriers, a dual-signal nanocomposite of TA/MoS 2 @AuNRs was steadily constructed. The nanocomposite possesses excellent signal transmission and photothermal properties because of the high NIR absorption cross-section and signal intensity of AuNRs as well as strong photothermal conversion efficiency of MoS 2. The TA/MoS 2 @AuNRs were used to prepare immunoprobes and then applied in the ICA. With 2-nitrobenzaldehyde semicarbazone (2-NPSEM) as the model analyte, the obtained competitive photothermal/colorimetric dual-signal readout ICA (PCICA) can monitor NPSEM colorimetrically and photothermally with a calculated sensitivity of 0.267 and 0.180 ng mL−1, respectively. Furthermore, the application feasibility of the immunoassay was further evaluated by measuring SEM in the honey sample with satisfactory recoveries ranging from 83.35% to 107.14% and coefficient of variation (CV) ranging from 0.12% to 7.63%. As a result, by introducing TA to exfoliate MoS 2 nanosheet, this work has proposed a more stable photothermal/colorimetric platform and provide an invigorating pathway for the appliance of MoS 2 -related photothermal materials in point-of-care immunoassays. • Tannic acid was introduced to construct a dual signal nanolabel (TA/MoS 2 @AuNRs). • A dual-readout biosensor was successfully applied to detect SEM in food samples. • Background-free and high accuracy are achieved with photothermal/colorimetric ICA. • The TA-mediated exfoliating broadens the appliance of MoS 2 related materials in ICA. [ABSTRACT FROM AUTHOR]

• NiS 2 is first used as a signal substrate in the dipstick immunoassay. • NiS 2 NPs have good biocompatibility, photothermal performance, and biodegradability. • Quantitative analysis by thermal imager improves the detection sensitivity. • Double signal immunoassay can improve the accuracy and sensitivity of detection. Immunochromatographic assay platforms are up-and-coming detection tools for disease diagnosis and harmful substances monitoring in food. Herein, by combining photothermal imaging and immunochromatographic analysis, a photothermal immunoassay is developed for the rapid and ultrasensitive detection of nitrofurazone. The nickel disulfide nanosphere with excellent biocompatibility, biodegradability, and high photothermal conversion efficiency, is introduced to offer straightforward readout by color and temperature based on the nature of the crystal, without advanced equipment. It is demonstrated that the nitrofurazone metabolite of semicarbazide can be qualitatively detected by colorimetric signals with a visual limit of 2 μg kg−1. And the quantitative detection limit of photothermal signals is 0.01 μg kg−1, improving the detection sensitivity by about 200 times. Furthermore, recovery rates of the proposed method in food samples were 93 %-120 %. This photothermal immunoassay not merely provides straightforward, rapid, simultaneous qualitative/quantitative detection tactics but may also be valuable in automated and portable diagnostic applications. [ABSTRACT FROM AUTHOR]

• Bismuth sulfide nanoparticles (Bi 2 S 3 NPs) were used for the first time as a signal substrate in LFIA. • Bi 2 S 3 NPs can connect to the anti-clenbuterol monoclonal antibody (mAb) through hydrogen bonding force. • As a label tag, more mAbs are bound by Bi 2 S 3 NPs, and Bi 2 S 3 NPs-mAb has binding stability. • The analysis results of milk, beef, and pork, show that Bi 2 S 3 NPs-LFIA has excellent practicability in food samples. Improving detection sensitivity is still a major research emphasis for lateral flow immunoassay (LFIA). Increasing the binding efficiency and stability of the probe is an achievable and effective solution. In this work, we developed a highly sensitive lateral flow immunoassay for clenbuterol detection by using bismuth sulfide nanoparticle (Bi 2 S 3) nanoparticles (NPs) as a novel marker. Here, Bi 2 S 3 NPs can link with the antibody by hydrogen bonding to improve the performance of the probe, e.g., stability and sensitivity. Benefiting from the direct hydrogen bonding between Bi 2 S 3 NPs and the monoclonal antibody (mAb), high sensitivity is obtained by the proposed LFIA with a lower visible detection limit of 0.1 ng mL−1 and a cut-off value of 4 ng·mL−1 for CLE detection, which is 5-fold and 7.5-fold improved than the conventional Au NPs based LFIA. In addition, the encouraging practical application results in milk, pork, and beef show that the bismuth sulfide nanoparticle has a great popularizing potential in the performance promotion of LFIAs for food safety monitoring. [ABSTRACT FROM AUTHOR]

First principles calculations are adopted to study the spin polarization properties of thiophene molecule which adsorbed at the Co, Fe, and Ni electrode surfaces. The density of states, spin-polarized density distributions as well as the differential charge density distributions are obtained. It is found that the p orbital of the thiophene molecule will interact with the d orbital of the ferromagnetic electrodes, which will generate new spin coupling states and lead to obvious spin polarization in the thiophene molecule. Different electrodes induce different spin polarization properties, and in which the Fe electrode will bring the biggest spin polarization of the thiophene molecule. People can selectively and efficiently inject spin polarized electrons into molecules by choosing suitable ferromagnetic electrodes in organic spintronic devices. [ABSTRACT FROM AUTHOR]

A p–n heterostructure hybrid based on polyaniline–SnO2 was synthesized by a rapid and facile in situ chemical oxidation polymerization at very low monomer concentration, and the hybrid was loaded on a flexible polyethylene terephthalate (PET) film substrate to structure a smart triethylamine (TEA) sensor. The structure, morphology and composition of the hybrid have been characterized by various analysis methods. The sensor not only exhibits high sensitivity, good selectivity to some other volatile organic compounds and wide linear response to 10–100 ppm triethylamine (TEA) at room temperature but is also flexible, has a simple structure and wearable performance. The mechanism of enhanced gas sensing is discussed in detail, which is attributed to the thickening of the depletion layer due to the formation of a p–n heterojunction at an interface in the hybrid. The research is expected to open a new window for the development of a kind of portable and wearable electronic device based on various p–n heterostructure hybrids. [ABSTRACT FROM AUTHOR]

We prepared a heterostructure hybrid of PANI and SnO 2 by a rapid and facile in situ chemical oxidation polymerization under very low monomer concentration, and the hybrid was loaded on a flexible PET thin film to structure a smart NH 3 sensor. The structure, morphology and thermal stability of the hybrid were characterized by various analysis methods. Compared with those reported in literatures, the hybrid-based sensor not only has high sensitivity, good selectivity and wide linear response to NH 3 at room temperature of 21 °C but also has flexible, structure simple and wearable performance. The room temperature operating of the sensor is particularly interesting, which leads to low-power consumption, environmental safety and long life times of the sensing materials. The improvement of sensing properties is attributed to the complementary and synergistic effect between SnO 2 and PANI, and formation of p−n heterojunction at the interface in hybrid. [ABSTRACT FROM AUTHOR]

The type VI protein secretion system ( T6SS) is essential for the virulence of several Gram-negative bacteria. In this study, we identified a T6SS gene cluster in Acidovorax citrulli, a plant-pathogenic bacterium that causes bacterial fruit blotch ( BFB) of cucurbits. One T6SS cluster, of approximately 25 kb in length and comprising 17 genes, was found in the A. citrulli AAC00-1 genome. Seventeen A. citrulli mutants were generated, each with a deletion of a single T6SS core gene. There were significant differences in BFB seed-to-seedling transmission between wild-type A. citrulli strain, xjl12, and Δ vas D, Δ imp K, Δ imp J and Δ imp F mutants (71.71%, 9.83%, 8.41%, 7.15% and 5.99% BFB disease index, respectively). In addition, we observed that these four mutants were reduced in melon seed colonization and biofilm formation; however, they were not affected in virulence when infiltrated into melon seedling tissues. There were no significant differences in BFB seed-to-seedling transmission, melon tissue colonization and biofilm formation between xjl12 and the other 13 T6SS mutants. Overall, our results indicate that T6SS plays a role in seed-to-seedling transmission of BFB on melon. [ABSTRACT FROM AUTHOR]

Manipulation of brown adipose tissue (BAT) and browning of white adipose tissue (WAT) can be promising new approaches to counter metabolic disorder diseases in humans. Imaging probes that could consistently monitor BAT mass and browning of WAT are highly desirable. In the course of our imaging probe screening, we found that BAT could be imaged with curcumin analogues in mice. However, the poor BAT selectivity over WAT and short emissions of the lead probes promoted further lead optimization. Limited uptake mechanism studies suggested that CD36/FAT (fatty acid transporter) probably contributed to the facilitated uptake of the probes. By increasing the stereo-hindrance of the lead compound, we designed CRANAD-29 to extend the emission and increase the facilitated uptake, thus increasing its BAT selectivity. Our data demonstrated that CRANAD-29 had significantly improved selectivity for BAT over WAT, and could be used for imaging BAT mass change in a streptozotocin-induced diabetic mouse model, as well as for monitoring BAT activation under cold exposure. In addition, CRANAD-29 could be used for monitoring the browning of subcutaneous WAT (sWAT) induced by β3-adrenoceptor agonist CL-316, 243. [ABSTRACT FROM AUTHOR]

The influences of stewing times (1, 2, 3, 4, 5, and 6 h) on total sugar, total lipids, water-soluble proteins, ζ-potential, particle size, stability index, microstructure, and volatile compounds of chicken soup were investigated, and the taste and aroma profiles of chicken soup were evaluated using a sensory panel. The results showed the self-emulsifying chicken soup obtained after stewing for 4 h had the highest stability index. The improvement in stability index was connected with the increase of soluble protein and ζ-potential and the decrease of particle size. Optical microscope, confocal laser scanning microscope, and scanning electron microscope observations showed that oil droplets and the particles in the soup were small and uniformly dispersed when the stewing time reached 4 h. Additionally, GC-MS analysis showed that the types and relative percentage contents of volatiles in the chicken soup changed with the extension of stewing time. The flavor composition variation was tending towards stability after stewing for 4 h, and the sensory evaluation results also showed that the scores of umami, saltiness and aroma of chicken soup were no longer significantly increased. In general, a balance between stability and flavor formation of the self-emulsifying chicken soup achieved after 4 h of stewing. This study provided a basic information for high-quality chicken soup. • The self-emulsifying chicken soup obtained after stewing for 4 h had high stability index. • The oil droplets and particles in the soup were uniformly dispersed when the stewing reached 4 h. • The flavor composition variation in the chicken soup tended to be stable after 4 h of stewing. [ABSTRACT FROM AUTHOR]

Polypyrrole (PPy)-reduced graphene oxide (rGO) hybrid was successfully synthesized by a facile in situ polymerization. The as-synthesized PPy nanoparticles with diameter of ca. 80 nm were uniformly distributed on the surface of the rGO sheets to prepare the hybrid of PPy/rGO. Then the pure PPy and their hybrids were loaded on the substrate of flexible polyethylene terephthalate (PET) film to construct a thin film NH 3 sensor, which has the advantages of being flexible, economical, portable and able to operable at room temperature (RT). The gas-sensing results reveal that the 5 wt% rGO-PPy hybrid based sensor not only exhibits the highest response to 10 ppm NH 3 , which is 2.5 times higher than that of pure PPy, but also excellent selectivity to some of VOCs. The enhancement of gas-sensing properties may be attributed to the π-π stacking and H-bonding formation between PPy and rGO, larger surface accessibility and fast transport of carriers. [ABSTRACT FROM AUTHOR]

We fabricated the PPy/WO 3 hybrids with p-n heterojunction by in situ chemical oxidation polymerization and loaded on a substrate of flexible PET thin film to structure a smart triethylamine sensor. The structure, morphology and thermal stability of the hybrid were characterized by various analysis methods. The sensing properties of the sensor to trace amounts of TEA were examined at room temperature. Compared to those reported in literature, the smart sensor not only exhibits high sensitivity, good selectivity and wide linear response to triethylamine at room temperature but also has been flexible, structure simple and portable performance. The mechanism of enhancing gas sensing properties was discussed in detail, which is attributed to the complementary effect and the formation of p-n heterojunction at an interface between WO 3 and PPy. The research is expected to open a new window for development of a kind of flexible and wearable electronic devices based on various heterostructure hybrids. [ABSTRACT FROM AUTHOR]

Background Systemic sclerosis ( SSc) is the most severe connective tissue disorder. Recent studies have demonstrated that genetic factors may play a role in the development of SSc. The aim of this study was to investigate the association of signal transducer and activator of transcription 4 ( STAT4) rs7574865 and interferon regulatory factor 5 ( IRF5) rs2004640 polymorphisms with risk of SSc. Methods Case-control studies were obtained from the electronic database of Pub Med, Medline, Embase, and CNKI ( China National Knowledge Infrastructure) up to December 2013. The association between STAT4 and IRF5 polymorphisms and SSc susceptibility was assessed by pooled odds ratios ( ORs) and 95% confidence intervals ( CI). Results Six related studies, including 4746 SSc cases and 7399 healthy controls, were pooled in this meta-analysis. For STAT4 polymorphism, we observed a statistically significant positive association between risk factor T allele carriers and SSc susceptibility ( OR = 1.37, 95% CI = 1.27-1.48, P < 0.00001) in the overall population. The presence of limited cutaneous (lc SSc) and diffuse cutaneous (dc SSc) scleroderma also showed a significant association with each of the genetic models ( P < 0.00001). For IRF5 polymorphism, the T allele was shown to be strongly associated with increased SSc risk ( OR = 1.27, 95% CI = 1.17-1.39, P < 0.00001). No significant heterogeneity between studies was found. Conclusions The results demonstrated that STAT4 rs7574865 and IRF5 rs2004640 G/ T substitution are associated with a susceptibility to SSc, and they may serve as the SSc genetic susceptibility factor. These data confirmed that genetic polymorphisms may play a role in the development of SSc and have provided new insight into the pathogenesis of SSc. [ABSTRACT FROM AUTHOR]

Clonorchis sinensis ( C. sinensis) infection is still a common public health problem in freshwater fish consumption areas in Asian countries. More molecular evidence are required to speed up the prevention strategies to control this kind of infectious disease. In the present study, to confirm the biological importance of Csenolase followed by our previous observations of the key metabolic enzyme, we explored the RNA silence effect of the Csenolase-derived RNA interference (RNAi) in C. sinensis. The extramembranous region aa was selected as the target sequence of RNA silence. Csenolase-derived double strand RNA (dsRNA- Csenolase, 366 bp) was synthetized and delivered into C. sinensis by soaking approach. The penetration of dsRNA into adult worms and metacercariae was tracked using fluorescently labeled RNA. Western blotting and qRT-PCR experiments were performed to determine dsRNA- Csenolase-silencing effect. Our results showed that, after incubating for 120 h, dsRNA- Csenolase could effectively target and downregulate the expression of Csenolase in both adult worms ( P < 0.001) and metacercariae ( P < 0.01), resulting in a remarkable killing effect on C. sinensis adult worms ( P < 0.01). Fluorescent Cy3-labeled dsRNA was mostly deposited in the uterus and vitellarium of adult worm and in the cyst wall of metacercaria. The present study is the first report of RNAi trials in C. sinensis, allowing further applications in identifying functional genes in C. sinensis. [ABSTRACT FROM AUTHOR]

Highlights: [•] The shuttle genetic engineering system facilitated the development of oral vaccine with Bacillus subtilis stably overexpressing target protein. [•] Csenolase derived vaccines administrated in different immunization routes could induce a mixed IgG1/IgG2a immune response. [•] Killed spores expressing Csenolase could trigger reactive Th1/Th2 immune response and exhibited protective efficacy against C. sinensis infection. [Copyright &y& Elsevier]

The molecular mechanisms underlying slow inactivation in sodium channels are elusive. Our results suggest that EEDD, a highly conserved ring of charge in the external vestibule of mammalian voltage-gated sodium channels, undermines slow inactivation. By employing site-directed mutagenesis, we found that charge alterations in this asymmetric yet strong local electrostatic field of the EEDD ring significantly altered the kinetics of slow inactivation gating. Using a non-linear Poisson–Boltzmann equation, quantitative computations of the electrostatic field in a sodium channel structural model suggested a significant electrostatic repulsion between residues E403 and E758 at close proximity. Interestingly, when this electrostatic interaction was eliminated by the double mutation E403C + E758C, the kinetics of recovery from slow inactivation of the double-mutant channel was retarded by 2500% compared to control. These data suggest that the EEDD ring, located within the asymmetric electric field, is a molecular motif that critically modulates slow inactivation in sodium channels. [ABSTRACT FROM AUTHOR]

Background: Pseudomonas syringae is an important plant pathogen, which could adapt many different environmental conditions. Under the nutrient-limited and other stress conditions, P. syringae produces nucleotide signal molecules, i.e., guanosine tetra/pentaphosphate ((p)ppGpp), to globally regulate gene expression. Previous studies showed that (p) ppGpp played an important role in regulating virulence factors in P. syringae pv. tomato DC3000 (PstDC3000) and P. syringae pv. syringae B728a (PssB728a). Here we present a comparative transcriptomic analysis to uncover the overall effects of (p)ppGpp-mediated stringent response in P. syringae. Results: In this study, we investigated global gene expression profiles of PstDC3000 and PssB728a and their corresponding (p)ppGpp0 mutants in hrp-inducing minimal medium (HMM) using RNA-seq. A total of 1886 and 1562 differentially expressed genes (DEGs) were uncovered between the (p)ppGpp0 mutants and the wild-type in PstDC3000 and PssB728a, respectively. Comparative transcriptomics identified 1613 common DEGs, as well as 444 and 293 unique DEGs in PstDC3000 and PssB728a, respectively. Functional cluster analysis revealed that (p) ppGpp positively regulated a variety of virulence-associated genes, including type III secretion system (T3SS), type VI secretion system (T6SS), cell motility, cell division, and alginate biosynthesis, while negatively regulated multiple basic physiological processes, including DNA replication, RNA processes, nucleotide biosynthesis, fatty acid metabolism, ribosome protein biosynthesis, and amino acid metabolism in both PstDC3000 and PssB728a. Furthermore, (p) ppGpp had divergent effects on other processes in PstDC3000 and PssB728a, including phytotoxin, nitrogen regulation and general secretion pathway (GSP). Conclusion: In this study, comparative transcriptomic analysis reveals common regulatory networks in both PstDC3000 and PssB728a mediated by (p) ppGpp in HMM. In both P. syringae systems, (p) ppGpp re-allocate cellular resources by suppressing multiple basic physiological activities and enhancing virulence gene expression, suggesting a balance between growth, survival and virulence. Our research is important in that due to similar global gene expression mediated by (p) ppGpp in both PstDC3000 and PssB728a, it is reasonable to propose that (p) ppGpp could be used as a target to develop novel control measures to fight against important plant bacterial diseases. [ABSTRACT FROM AUTHOR]

Summary: Pseudomonas syringae pv. tomato DC3000 (PstDC3000) contains five RsmA protein homologues. In this study, four were functionally characterized, with a focus on RsmA2, RsmA3 and RsmA4. RNA electrophoretic mobility shift assays demonstrated that RsmA1 and RsmA4 exhibited similar low binding affinities to non‐coding small RNAs (ncsRNAs), whereas RsmA2 and RsmA3 exhibited similar, but much higher, binding affinities to ncsRNAs. Our results showed that both RsmA2 and RsmA3 were required for disease symptom development and bacterial growth in planta by significantly affecting virulence gene expression. All four RsmA proteins, especially RsmA2 and RsmA3, influenced γ‐amino butyric acid utilization and pyoverdine production to some degree, whereas RsmA2, RsmA3 and RsmA4 influenced protease activities. A single RsmA, RsmA3, played a dominant role in regulating motility. Furthermore, reverse transcription quantitative real‐time PCR and western blot results showed that RsmA proteins, especially RsmA2 and RsmA3, regulated target genes and possibly other RsmA proteins at both transcriptional and translational levels. These results indicate that RsmA proteins in PstDC3000 exhibit distinct binding affinities to ncsRNAs and have distinct roles in virulence. Our results also suggest that RsmA proteins in PstDC3000 interact with each other, where RsmA2 and RsmA3 play a major role in regulating various functions in a complex manner. [ABSTRACT FROM AUTHOR]

A rapid, sensitive and visual loop‐mediated isothermal amplification (LAMP) method for detecting Acidovorax citrulli in cucurbit seed was developed in this study. The LAMP primers were designed to recognize the non‐ribosomal peptide synthetase (NRPS) gene (locus tag: Aave_4658) from A. citrulli. The LAMP assay was conducted at 64°C in 1 hr with calcein as an indicator. The sensitivity and specificity of the LAMP assay were further compared with those of a conventional polymerase chain reaction (PCR). The LAMP assay is highly specific to A. citrulli, and no cross‐reaction was observed with other bacterial pathogen. The sensitivity of the LAMP assay was 100‐fold higher than that of conventional PCR with a detection limit of 1 pg of genomic DNA. Using the LAMP assay, 7 of 12 cantaloupe seedlots collected from Xinjiang province were determined to be positive for A. citrulli. In contrast, only 2 of 12 seedlots showed positive for the pathogen with conventional PCR. Moreover, A. citrulli was detected in 100% of artificially infested seedlots with 0.01% infestation or greater. Our results demonstrated that the LAMP assay was simple, visual and sensitive for detecting A. citrulli, especially in seed health testing. Hence, this method has great potential application in routine detecting seed‐borne pathogens and reducing the risk of epidemics. [ABSTRACT FROM AUTHOR]

Portable devices for on-site foodborne pathogens detection are urgently desirable. Lateral flow immunoassay (LFIA) provides an efficient strategy for pathogens detection, however, antibody labeling independence and detection reliability, are still challenging. Here, we report the development of a label-free LFIA with dual-readout using glucan-functionalized two-dimensional (2D) transition metal dichalcogenides (TMDs) tungsten disulfide (WS 2) as detection probes for sensitive detection of Salmonella enteritidis (S. enteritidis). In particular, glucan-functionalized WS 2 , synthesized via liquid exfoliation, are reliable detection antibody candidates which served as antibody mimics for bacteria capturing. This LFIA has not only eliminated the intricate antibody labeling process and screening of paired antibodies in conventional LFIAs, but also promised dual-readout (colorimetric/Raman) for flexible detection. Under optimized conditions, this LFIA achieves selective detection of S. enteritidis with a low visual detection limit of 103 CFU/mL and a broad linear range of 103−108 CFU/mL. Additionally, the LFIA could be successfully applied in drinking water and milk with recoveries of 85%–109%. This work is desirable to expand the application of 2D TMDs in biosensors and offers a brand-new alternative protocol of detection antibodies in foodborne pathogens detection. [ABSTRACT FROM AUTHOR]

Immunochromatographic test strips (ITSs) have gained great practicability in point-of-care testing (POCT). Developing novel labels of ITSs with an additional signal to carry out quantitative analysis favors the development of sensitive POCT. Herein, tannic acid (TA) assisted stripping WS 2 nanosheets (TA-WS 2 NSs) based on colorimetric/photothermal ITS (TWITS) for clenbuterol (CLE) monitoring. After WS 2 NSs loaded TA, it retained excellent photothermal performance and an intact surface structure for monoclonal antibody (mAb) labeling, at the same time, the stability of WS 2 NSs and the activity of mAb were improved effectively. Satisfactory, the visual limit of detection (vLOD) of the photothermal signal was 0.3 ng/mL, which was enhanced 7-fold at least compared with traditional gold-based nanoparticles ITS (GNPs ITS). Importantly, this work can offer a new referenced method for other small molecule pollutants. • Developed a sensitive colorimetric/photothermal sensor for clenbuterol detecting in food. • Tannic acid improved effectively the stability of WS 2 NSs and the activity of monoclonal antibody. • The result of quantitative analysis effectively improve the visual limit of detection (vLOD) of the strip. [ABSTRACT FROM AUTHOR]

The paper dip-stick immunoassay (DSIA) is rapid, cheap, and easy to produce. As a modified lateral flow immunoassay, DSIA also has obtained significant attention in point-of-care testing (POCT). Investigating more diverse signal carriers for paper immunoassay has always been a research hotspot. In this work, a dual reading (color/catalytic signal) DSIA based on the multifunctional material NiCo 2 O 4 (NCO) is developed for detecting 17β-estradiol (E2). NCO is highly stable and possesses inherent properties of dark black color, nanozyme activity, and magnetism. The colorimetric and catalytic signals-based method of immunoassay strips can obtain a more accurate result maximally. The double reading NCO-DSIA can obtain a limit of detection of 0.2 ng mL−1 and 1 ng mL−1 for E2 under colorimetric and catalysis signals, respectively. In addition, the magnetic property of NCO can contribute to inhibiting the matrix effect of food samples. Furthermore, this non-composite multifunctional nanomaterial-based DSIA has potential development prospects for pollutants detection. [Display omitted] • A dual reading dip-stick immunoassay (DSIA) is proposed for 17β-estradiol detecting. • Non-composite multifunctional NiC 2 O 4 (NCO) is first developed in the DSIA. • Dual reading mode is benefited from the black color and nanozyme activity of NCO. • Both more accurate result and lower matrix effect are realized in the NCO-based DSIA. [ABSTRACT FROM AUTHOR]

Owing to the lack of a universal descriptor to predict the nanozymes as signal markers (SM) of immunochromatographic analysis (ICA), the present exploitation of nanozymes as SM heavily relies on trial-and-error strategies, which obstructs the rational design of nanozymes with monoclonal antibodies (mAbs) recognition activity. Herein, inspired by the structure of the active center of natural multi-iron peroxidases and polyphenol-protein interactions, a rational design of an artificial peroxidase with mAbs recognition activity by utilizing gallic acid (GA) to chelate with multivalent iron was successfully proposed by utilizing gallic acid (GA) to chelate with multivalent iron. The most essential features of peroxidase-like Fe-GA nanozymes (FGN) were investigated, showing high catalytic performance and good stability. Subsequently, FGN was employed as SM for mAbs in ICA, which played the following triple roles in the ICA sensor: (i) the direct recognizer of mAbs; (ii) the generator of original colorimetric signal; (iii) the generator of catalytic in-suit amplification colorimetric signal. To make the ICA more portable, we have employed a smartphone and principal component analysis (PCA) to assist this on-site detection. As a proof-of-concept, clenbuterol (CLL) was analyzed by the proposed nanozymes-mediated dual-colorimetric ICA based on a smartphone. Notably, the proposed dual-colorimetric ICA exhibits high analytical performance for the quantification of CLL in the detection range of 0–6 ng mL−1 with a limit of detection (LOD) as low as 0.172 ng mL−1. Meanwhile, the proposed dual-colorimetric ICA exhibits remarkable feasibility and was successfully employed for the detection of CLL in pork and chicken matrixes. [ABSTRACT FROM AUTHOR]

Exploring a nanozyme as a nanocarrier for the enzyme-labeled antibodies (ELA) in the enzyme-linked immunosorbent assay (ELISA) is beneficial in improving the analytical performance of ELISA. Herein, a white Fe-based coordination polymer nanozyme (FCPN) was fabricated as a nanocarrier for the ELA to improve the catalytic activity and relieve the color interference of nanoprobes in ELISA. The proposed enhanced catalytic immunoassay (ECI) exhibits high analytical performance for the quantification of clenbuterol (CLL) in the detection range of 0.09–10 ng mL−1 with a limit of detection (LOD) as low as 0.09 ng mL−1, improving the detection sensitivity nearly 3.5 times compared with the conventional ELISA. Meanwhile, the usage of anti-CLL monoclonal antibodies in this proposed ECI was economizes by 6.7 times and the detection sensitivity was increased by nearly 4.5 times compared with our previous research. In addition, the detection sensitivity of the ECI using a white nanozyme as a nanocarrier is 2.3 times higher than using a blue Cu-based metal organic framework (Cu-MOF) nanozyme. Meanwhile, the applicability of the proposed ECI was successfully demonstrated by the detection of CLL in pork meat and pork liver with recoveries ranging from 92.51% to 110.16%. • Improved sensitivity and a wider detection range are both obtained in this assay. • The white FCPN nanozymes have higher analytical performances over blue Cu-MOF. • This assay economizes the usage of antibodies compared with our previous work. [ABSTRACT FROM AUTHOR]

This work investigated microbubble-ozonation for the treatment of a refractory wet-spun acrylic fiber wastewater in comparison to macrobubble-ozonation. COD cr , NH 3 -N, and UV 254 of the wastewater were removed by 42%, 21%, and 42%, respectively in the microbubble-ozonation, being 25%, 9%, and 35% higher than the removal rates achieved by macrobubble-ozonation at the same ozone dose. The microbubbles (with average diameter of 45 μm) had a high concentration of 3.9 × 10 5 counts/mL at a gas flow rate of 0.5 L/min. The gas holdup, total ozone mass-transfer coefficient, and average ozone utilization efficiency in the microbubble-ozonation were 6.6, 2.2, and 1.5 times higher than those of the macrobubble-ozonation. Greater generation of hydroxyl radicals and a higher zeta potential of the bubbles were also observed in the microbubble ozonation process. The biodegradability of the wastewater was also significantly improved by microbubble-ozonation, which was ascribed to the enhanced degradation of alkanes, aromatic compounds, and the many other bio-refractory organic compounds in the wastewater. Microbubble-ozonation can thus be a more effective treatment process than traditional macrobubble-ozonation for refractory wastewater produced by the acrylic fiber manufacturing industry. [ABSTRACT FROM AUTHOR]

Clonorchiasis, caused by direct and continuous contact with Clonorchis sinensis, is associated with hepatobiliary damage, inflammation, periductal fibrosis, and the development of cholangiocarcinoma. Hepatic stellate cells respond to liver injury through production of proinflammatory mediators which drive fibrogenesis; however, their endogenous sources and pathophysiological roles in host cells were not determined. C. sinensis ferritin heavy chain ( CsFHC) was previously confirmed as a component of excretory/secretory products and exhibited a number of extrahepatic immunomodulatory properties in various diseases. In this study, we investigated the expression pattern and biological role of CsFHC in C. sinensis. CsFHC was expressed throughout life stages of C. sinensis. More importantly, we found that treatment of human hepatic stellate cell line LX-2 with CsFHC triggered the production of free radicals via time-dependent activation of NADPH oxidase, xanthine oxidase, and inducible nitric oxide synthase. The increase in free radicals substantially promoted the degradation of cytosolic IκBα and nuclear translocation of NF-κB subunits (p65 and p50). CsFHC-induced NF-κB activation was markedly attenuated by preincubation with specific inhibitors of corresponding free radical-producing enzyme or the antioxidant. In addition, CsFHC induced an increased expression level of proinflammatory cytokines, IL-1β and IL-6, in NF-κB-dependent manner. Our results indicate that CsFHC-triggered free radical-mediated NF-κB signaling is an important factor in the chronic inflammation caused by C. sinensis infection. [ABSTRACT FROM AUTHOR]

Invasive trichosporonosis is a deep mycosis found mainly in immunocompromised hosts, and the major pathogen is Trichosporon asahii. We detected the species-specific intergenic spacers (IGS) of rRNA gene of T. asahii using a loop-mediated isothermal amplification (LAMP) assay in 15 isolates with 3 different visualization methods, including SYBR green detection, gel electrophoresis, and turbidimetric methods. The LAMP assay displayed superior rapidity to other traditional methods in the detection time; that is, only 1 h was needed for detection and identification of the pathogen DNA. Furthermore, the detection limit of the LAMP assay was more sensitive than the PCR assay. We also successfully detect the presence of T. asahii in samples from experimentally infected mice and samples from patients with invasive trichosporonosis caused by T. asahii, suggesting that this method may become useful in clinical applications in the near future. [ABSTRACT FROM AUTHOR]

A diversity-orientedone-pot synthesis of a series of membrane-permeableBF2-rigidified benz[c,d]indole N-heteroarene BBN and BBC dyes has beenachieved from the condensation of two commercial components (benz[c,d]indol-2-one and a set of N-heteroarene derivatives that can be selected from thousands of commerciallyavailable sources) and the subsequent in situ BF2complexationreaction. These dyes enjoy a set of excellent photophysical propertiesincluding the large Stokes shift, high solution and solid-state fluorescence,and excellent photostabilities. [ABSTRACT FROM AUTHOR]

Clonorchis sinensis excretory/secretory products (ESP) have gained high attentions because of their potential to be vaccine candidates and drug targets in C. sinensis prevention. In this study, we extensively profiled the characteristics of four C. sinensis cathepsin B cysteine proteases ( CsCB1, CsCB2, CsCB3, and CsCB4). Bioinformatics analysis showed all CsCBs contained signal peptides at the N-terminal. Functional domains and residues were found in CsCB sequences. We expressed four CsCBs and profiled immune responses followed by vaccine trials. Recombinant CsCBs could induce high IgG titers, indicating high immunogenicity of CsCB family. Additionally, ELISA results showed that both IgG1 and IgG2a levels apparently increased post-immunization with all four CsCBs, showing that combined Th1/Th2 immune responses were triggered by CsCB family. Both Real-time polymerase chain reaction (RT-PCR) and Western blotting confirmed that four CsCBs have distinct expression patterns in C. sinensis life stages. More importantly, we validated our hypothesis that CsCBs were C. sinensis excretory/secretory products. CsCBs could be recognized by C. sinensis-infected sera throughout the infection period, indicating that secreted CsCBs are immune triggers during C. sinensis infection. The protective effect was assessed by comparing the worm burden and egg per gram (EPG) between CsCB group and control group, showing that worm burden ( P < 0.01) and EPG ( P < 0.01) in CsCB2 and CsCB3 groups were significantly lower than in control group. In conclusion, we profiled secreted cathepsin B cysteine proteases family for the first time and demonstrated that all CsCB family were C. sinensis excretory/secretory products that may regulate host immune responses. [ABSTRACT FROM AUTHOR]

The vacuolar ATPase enzyme complex (V-ATPase) pumps protons across membranes, energized by hydrolysis of ATP. Extensive investigations on structural and biochemical features of these molecules have implied their importance in the physiological process. In this study, a full-length sequence encoding a vacuolar ATP synthase subunit ε-like protein of Clonorchis sinensis ( CsATP-ε) was isolated from our cDNA library. The hypothetical 226 amino acid sequence shared 76 % identity with ATP-ε proteins of Schistosoma japonicum and above 55 % identity with ATP-ε proteins from human and other eukaryotes. Characteristic Asp amino acid residues and seven B-cell epitopes were predicted in this sequence. The complete coding sequence of the gene was expressed in Escherichia coli. Recombinant CsATP-ε (r CsATP-ε) protein could be probed by anti-r CsATP-ε rat serum and C.sinensis-infected human serum in Western blotting experiment, indicating that it is an antigen of strong antigenicity. The high level of antibody titers (1:204,800) showed that CsATP-ε has a powerful immunogenicity. Both the increased level and the change trend of IgG1/IgG2a subtypes in serum showed that the r CsATP-ε can induce strong combined Th1/Th2 immune responses in rats and stimulate the immune response changes to the dominant Th2 from Th1 along with long time infection. The results of immunoblot and immunolocalization demonstrated that CsATP-ε was consecutively expressed at various developmental stages of the parasite, which was supported by real-time PCR analysis. In immunohistochemistry, CsATP-ε was localized on the intestine, vitellarium, and testicle of an adult worm and excretory bladder of metacercaria, implying that CsATP-ε may relate to energy intake and metabolism. This fundamental study would contribute to further researches that are related to growth and development and immunomodulation of C. sinensis. [ABSTRACT FROM AUTHOR]

Clonorchis sinensis, an ancient parasite that infects a number of piscivorous mammals, attracts significant public health interest due to zoonotic exposure risks in Asia. The available studies are insufficient to reflect the prevalence, geographic distribution, and intraspecific genetic diversity of C. sinensis in endemic areas. Here, a multilocus analysis based on eight genes (ITS1, act, tub, ef-1a, cox1, cox3, nad4 and nad5 [4.986 kb]) was employed to explore the intra-species genetic construction of C. sinensis in China. Two hundred and fifty-six C. sinensis isolates were obtained from environmental reservoirs from 17 provinces of China. A total of 254 recognized Multilocus Types (MSTs) showed high diversity among these isolates using multilocus analysis. The comparison analysis of nuclear and mitochondrial phylogeny supports separate clusters in a nuclear dendrogram. Genetic differentiation analysis of three clusters (A, B, and C) showed low divergence within populations. Most isolates from clusters B and C are geographically limited to central China, while cluster A is extraordinarily genetically diverse. Further genetic analyses between different geographic distributions, water bodies and hosts support the low population divergence. The latter haplotype analyses were consistent with the phylogenetic and genetic differentiation results. A recombination network based on concatenated sequences showed a concentrated linkage recombination population in cox1, cox3, nad4 and nad5, with spatial structuring in ITS1. Coupled with the history record and archaeological evidence of C. sinensis infection in mummified desiccated feces, these data point to an ancient origin of C. sinensis in China. In conclusion, we present a likely phylogenetic structure of the C. sinensis population in mainland China, highlighting its possible tendency for biogeographic expansion. Meanwhile, ITS1 was found to be an effective marker for tracking C. sinensis infection worldwide. Thus, the present study improves our understanding of the global epidemiology and evolution of C. sinensis. [ABSTRACT FROM AUTHOR]

Cysteine proteases play essential roles in parasite physiology as well as in host-parasite interactions through their modulation of various biological and pathobiological events. In the present study, a full-length sequence encoding cysteine protease of Clonorchis sinensis ( CsCP) was isolated from our adult cDNA library. The open reading frame contains 984 bp encoding 327 amino acids. The present amino acid sequence shared 68% identity with two known CsCP genes and 29-49% identity with that of other species. Bioinformatics analysis showed that conserved domains and characteristic amino acid residues of cysteine proteases were observed in this sequence. Real-time PCR experiments revealed that CsCP was consecutively transcribed in various developmental stages of the parasite, including adult worm, excysted juvenile, metacercaria and egg. Recombinant CsCP (r CsCP) could be probed by rat anti- CsCP serum, rabbit anti-excretory-secretory products (ESP) serum and serum from human infected with Clonorchis sinensis in Western blot. The result of immunolocalization showed that CsCP was mainly located in the oral sucker, excretory bladder and tegument of cercariae and metacercariae, as well as the intestine of adult worm. The r CsCP-based IgG and its isotypes were all detected in sera from human infected with C. sinensis by enzyme-linked immunosorbent assay, and the level of IgG1 is the highest. The receiver-operating characteristic (ROC) analysis was used to determine the most appropriate cut-off value that yielded the high sensitivity (86.96%) and specificity (70.42%). These results revealed that CsCP may play an important role in the biology of C. sinensis and could be a diagnostic candidate for clonorchiasis. [ABSTRACT FROM AUTHOR]

Abstract: Alterations of cardiac gene expression are central to ventricular dysfunction in human heart failure (HF). The canine tachycardia pacing-induced HF model is known to reproduce the main hemodynamic, echocardiographic and electrophysiological changes observed in human HF. In this study, we use this HF model to compare gene expression profiles in the left and right ventricles (LV, RV) of normal and end-stage failing canine hearts and compare the transcription profiles to those in human and murine models of HF. In end-stage HF, the LV exhibits down regulation of genes involved in energy production, cardiac contraction, and modulation of excitation–contraction coupling as compared with normal LV. The majority of transcriptomic changes between normal and end-stage canine HF were shared by the RV and LV. Genes down regulated only in the LV included those involved in aerobic energy production pathways, regulation of actin filament length, and enzyme-linked receptor protein signaling pathways. In normal canine hearts, genes encoding specific components of the contractile apparatus exhibit LV–RV asymmetric expression patterns; in failing hearts, cardiac fetal transcription factors MEF2 and MITF and the stress-responsive transcription factor ATF4 showed interventricular differences in expression. The comparison among the canine tachypacing, mouse transgenic, and human HF reveals that human disease involves down regulation of genes in a broad range of biological processes while experimentally induced HF is associated with down regulation of energy pathways, and that human ischemic HF and canine HF share a similar over representation of transcriptional pathways in the up regulated genes. This study provides insights into the molecular pathways leading to end-stage tachycardia-induced HF, and into global transcriptomic differences between the animal HF models and human HF. [Copyright &y& Elsevier]