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Vibrio vulnificus infection caused by contaminated aquatic products and seawater can lead to severe disease and high mortality. The development of a rapid and sensitive detection method for Vibrio vulnificus is vital to effectively prevent infection in advance. In this study, CeO 2 @PtRu with high peroxidase activity was used to construct a colorimetric immunoassay for Vibrio vulnificus detection by conjugating polyclonal antibodies via the biotin-streptavidin system. The developed colorimetric biosensor for Vibrio vulnificus demonstrated rapid operability and good sensitivity with a detection range from 104 CFU/mL to 109 CFU/mL, and the limit of detection (LOD) is 193 CFU/mL. Moreover, the colorimetric biosensor showed excellent specificity and good recoveries from 98.70% to 102.10% with RSD < 7.45% for spiked real samples. This novel CeO 2 @PtRu-based colorimetric biosensor has great application potential for the sensitive detection of Vibrio vulnificus in seafood. • A novel CeO 2 @PtRu nanozyme shows excellent peroxidase-like activity. • The colorimetric biosensor was constructed by conjugating CeO 2 @PtRu and polyclonal antibody via the biotin-streptavidin system. • High sensitive colorimetric detection for Vibrio vulnificus was realized by target-induced shielding against the peroxidase-mimicking activity of nanozymes. • The colorimetric biosensor exhibits good specificity and high accuracy for the detection of Vibrio vulnificus in seafood. [ABSTRACT FROM AUTHOR]

The solid-state diversity of active pharmaceutical ingredients can provide theoretical guidance for the production and storage of drugs. In this study, three solid forms of glipizide were obtained through various methods, and the solid-state transformations were extensively investigated. Form I could be prepared using evaporative crystallization, cooling crystallization, anti-solvent crystallization, and solvent-mediated slurry conversion experiments (SSCE). Form II was produced by milling. Form III was obtained by milling and SSCE. The results of solid-state transformations indicated that Form I transformed to II during neat milling at 25 °C. In contrast, solvent inhibited the solid-state transformations of Form I under liquid-assisted milling. Forms II and III remained invariable under neat milling at 25 °C, and solid-state transformation of Form III also did not occur in the liquid-assisted milling. In SSCE, the solvent's nature and its temperature significantly influenced the solid-state conversion of amorphous glipizide. Form II converted to either Form I or III in water above 50 °C, and only transformed into Form I at 25 °C. However, the solid-state transformation did not occur when pure Form I or III was stirred in water. Form II also converted to Form I in the organic solvents SSCE at different temperatures. [ABSTRACT FROM AUTHOR]

• CT-like chimeric protein enables co-delivery of epitopes and cytokine adjuvant. • Nasal administration of CT-like chimeric protein delayed the prostate tumor growth. • CT-like chimeric protein boosts CTL effects by promoting the maturation of DC. • Platform for screening PSMA specific epitopes in prostate cancer immunotherapy. Subunit vaccines derived from tumor antigens play a role in tumor therapy because of their unique advantages. However, because of the weak immunogenicity of peptides in subunit vaccines, it is difficult to trigger an effective cytotoxic T lymphocyte (CTL) response, which is critical for cancer therapy. A requirement for the activation of CTL cells by exogenous antigens is the stimulation of antigen presenting cells (APC) with the help of adjuvants and cross-presentation to T lymphocytes. Standard nonconjugated adjuvant-peptide mixtures do not ensure co-targeting of the antigen and the adjuvant to the same APC, which limits the effects of adjuvants. In this study, a fusion protein consisting of murine granulocyte-macrophage colony stimulating factor (mGM-CSF) fused with CTA2 (A2 subunit of cholera toxin) was generated and assembled with CTB-PSMA624-632 (prostate specific membrane antigen (PSMA) peptide 624–632 fused to CTB) to obtain a cholera toxin-like protein. The chimeric protein retained the biological activity of mGM-CSF and had stronger GM1 binding activity than (CTB-PSMA624-632)5. C57BL/6J mice immunized with the CT-like chimeric protein exhibited delayed tumor growth following challenge with human PSMA-EGFP-expressing RM-1 cells. Experiment results showed that the CT-like chimeric protein could induce the maturation of DC cells and improve CTL responses. Overall, these results indicate that the nasal administration of a CT-like chimeric protein vaccine results in the development of effective immunity against prostate tumor cells and might be useful for future clinical anti-tumoral applications. [ABSTRACT FROM AUTHOR]

To develop a sensitive fluorescence polarization immunoassay (FPIA) for detecting Diisobutyl phthalate (DIBP) in Yoghurt. Five tracers with different lengths of bridge between the hapten molecule and fluorescein isothiocyanate (FITC), fluoresceinthiocarbamyl ethylenediamine (EDF), fluoresceinthiocarbamyl hexylenediamine (HDF), were synthesized and their respective binding responses with anti-DIBP-specific antibody were evaluated. The physicochemical parameters were optimised for the FPIA. The FITC-labelled DIBP conjugate (DIBP-FITC) was found to be the optimal tracer for FPIA of Diisobutyl phthalate. The detection limit of DIBP, IC50 value and the working range were 0.82, 9.32 and 1.16–74.97 ng/mL, respectively; and the reaction time was only 5min. The average recovery from spiked Yoghurt samples was 77.80–115.60% which showed good reproducibility for FPIA. Thus, the developed FPIA method exhibited the potential for the rapid and accurate determination of DIBP in agricultural and environmental samples. Image 1 • A Fluorescence Polarization Immunoassay method to quantify Diisobutyl phthalate in Yoghurt samples. • The methods could be selectively used for rapid screening of Diisobutyl phthalate in Yoghurt. • The new method has some referential significance for the control the content of plasticizer in food. • The method was suitable for daily test of a large number of samples. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract C-peptide level is recognized as an important indicator of diabetes diagnosis. A sensitive and specific double-antibody sandwich enzyme-linked immunosorbent assay for the detection of C-peptide based on double antibody sandwich method was studied in this paper. The rabbit and hen were innunized with PLL-C-peptide and BSA-C-peptide respectively to obtain specific Yolk antibody (IgY) and polyclonal antibody used to construct the sandwich ELISA for the measurement of C-peptide. The limit of detection was 0.51 μg/mL and the half maximal inhibitory concentration (IC50) was 3.26 μg/mL. The method developed in the study showed no evident cross-reactivity with other similar analogs. The detection standard curve of C-peptide exhibited a good linearity (R2 = 0.9896, n = 15). 17 types of the urine of diabetes patients on c-peptide levels compared with the hospital type of diabetes information, with a conclusion of a high consistent rate. Therefore, the methods could be selectively used for rapid screening of C-peptide in human urine, and the type of diabetes has some referential significance. [ABSTRACT FROM AUTHOR]

In this paper, a simple, rapid and high-throughput fluorescence polarization immunoassay (FPIA) based on polyclonal antibodies (PAb) is described for the determination of glycocholic acid (GCA) in human urine. Three fluorescein-labeled GCA (tracers) with different structures and spacer bridges were synthesized and purified by thin-layer chromatography (TLC). The structure effect of tracers on the assay was investigated and the sensitivity of best tracer in the optimized FPIA demonstrated an IC 50 value of 306 ng/mL. The working range of FPIA was 36 ∼ 2 600 ng/mL and the limit of detection (LOD) was 9 ng/mL. The developed FPIA was time-saving that could be completed within 10 min. Human urine samples spiked with GCA were analyzed by this method, followed by confirmation with commercial enzyme immunoassay analysis (EIA). Excellent recoveries and correlation between these two methods were observed ( R 2  = 0.996), suggesting the developed FPIA could be applied to screening of GCA in human urine samples without complicated cleanup. [ABSTRACT FROM AUTHOR]

Epidermal growth factor receptor (EGFR) has gained significant attention as a therapeutic target. Several EGFR targeting drugs (Gefitinib and Erlotinib) have been approved by US Food and Drug Administration (FDA) and have received high approval in clinical treatment. Nevertheless, the curative effect of these medicines varied in many solid tumors because of the different levels of expression and mutations of EGFR. Therefore, several PET radiotracers have been developed for the selective treatment of responsive patients who undergo PET/CT imaging for tyrosine kinase inhibitor (TKI) therapy. In this study, a novel fluorine-18 labeled 4-anilinoquinazoline based PET tracer, 1 N -(3-(1-(2- 18 F-fluoroethyl)-1 H -1,2,3-triazol-4-yl)phenyl)-6,7-bis(2-methoxyethoxy)quinazolin-4-amine ( 18 F-FEA-Erlotinib), was synthesized and biological evaluation was performed in vitro and in vivo. 18 F-FEA-Erlotinib was achieved within 50 min with over 88% radiochemical yield (decay corrected RCY), an average specific activity over 50 GBq/μmol, and over 99% radiochemical purity. In vitro stability study showed no decomposition of 18 F-FEA-Erlotinib after incubated in PBS and FBS for 2 h. Cellular uptake and efflux experiment results indicated the specific binding of 18 F-FEA-Erlotinib to HCC827 cell line with EGFR exon 19 deletions. In vivo, Biodistribution studies revealed that 18 F-FEA-Erlotinib exhibited rapid blood clearance both through hepatobiliary and renal excretion. The tumor uptake of 18 F-FEA-Erlotinib in HepG2, HCC827, and A431 tumor xenografts, with different EGFR expression and mutations, was visualized in PET images. Our results demonstrate the feasibility of using 18 F-FEA-Erlotinib as a PET tracer for screening EGFR TKIs sensitive patients. [ABSTRACT FROM AUTHOR]

Fluorescent sensor assay (FSA) was developed by using a fluorescein-labeled aptamer assembled onto Graphene oxide (GO) in order to determine β-lactamase in milk. Under optimal conditions, FSA indicated a detection range from 1 to 46 U/mL with a limit of detection (LOD) of 0.5 U/mL ( R 2 = 0.999, n = 3). In addition, commercial milk samples tainted with β-lactamase were detected by the established FSA with a recovery rate between 96.04 and 119.67%. Additionally, the reliability and sensitivity of FSA was validated by enzyme-linked immunoassay (ELISA) with a high correlation of 0.993. Thus, these data, combined with the ease and speed of the assay, suggest that the developed FSA may represent a promising method for monitoring β-lactamase contamination in milk. [ABSTRACT FROM AUTHOR]

Alcohol-induced liver injury has become a leading risk for human health, however, effective strategies for the prevention or treatment are still lacking. Hence, the present study explored the potential of Musculus senhousei as a source of hepatoprotective peptides against alcoholic liver injury using in vitro , in vivo and in silico methods. Results indicated that Musculus senhousei peptides (MSP, extracted by simulated gastrointestinal digestion of cooked mussel) exhibited notable antioxidant (ABTS and DPPH assays) and alcohol dehydrogenase (ADH) stabilizing activity in vitro. The ingestion of MSP markedly alleviated alcohol-induced liver injury in mice, as indicated by the decrease of serum transaminases (AST and ALT). In line with in vitro assays, significantly increased hepatic ADH activity and activated antioxidative defense system (GSH, SOD, GSH-Px and CAT) were observed, whereas the oxidative stress (MDA) was decreased. Peptidomic analysis revealed over 6000 peptides with favorable amino acid compositions, and a total of 20 potentially novel peptides with bioactivity and bioavailability were excavated among 746 of the most influential peptides using an in silico strategy. Peptides (i.e. WLPMKL, WLWLPA, RLC and RCL) were further synthesized and validated in vitro to be bioactive. These findings suggest that Musculus senhousei can be an ideal source of bioactive peptides for the prevention of alcoholic liver injury. [ABSTRACT FROM AUTHOR]

Abstract: Four steroidal saponins were isolated from the anti-anoxic fraction of the 60% EtOH extract of Selaginella uncinata, including two new compounds, (3β, 7β, 12β, 25R)-spirost-5-ene-3, 7, 12-triol-3-O-α-L-rhamnopyranosyl-(1→2)-O-[α-L-rhamnopyranosyl-(1→4)]-O-β-d-glucopyranoside (1), (2α, 3β, 12β, 25R)-spirost-5-ene-2, 3, 12-triol-3-O-α-L-rhamnopyranosyl-(1→2)-O-[α-L-rhamnopyranosyl-(1→4)]-O-β-d-glucopyranoside (2) and two known compounds, (3β, 12β, 25R)-spirost-5-ene-3,12-diol-3-O-α-L-rhamnopyranosyl-(1→2)-O-[α-L-rhamnopyranosyl-(1→4)]-O-β-d-glucopyranoside, (3), (1α, 3β, 25R)-spirost-5-ene-2-diol-3-O-α-L-rhamnopyranosyl-(1→2)-O-[α-L-rhamnopyranosyl(1→4)]-O-β-d-glucopyranoside (4). The four compounds showed potent protective effect against anoxia in the anoxic PC12 cells assay, among which compounds 1 and 2 were the most active. To our knowledge, this is the first study to report the steroidal saponins in the plant S. uncinata and demonstrate their protective effect against anoxia in PC12 cell assay. [Copyright &y& Elsevier]

Seven new terpenes and its derivatives classified into a p -menthane glycoside (1), a guaianolide glycoside (2), three eudesmane and its glycosides (3 – 5), and two mono-terpene derivatives (9 and 10) were isolated from Ainsliaea bonatii , together with three known guaianolides (6 – 8). Their structures were elucidated by spectroscopic data analysis, and absolute configurations were determined by DP4+ probability analysis via calculated 13C NMR data of isomers. Compounds 6 and 9 showed nitric oxide (NO) inhibitory effects in LPS-induced RAW 264.7 macrophage cells with IC 50 values of 9.3 and 10.6 μ M, respectively. [Display omitted] • Seven new terpenes classified into mono-terpene, guaianolide and eudesmanolide types were isolated from Ainsliaea bonatii. • Their structures were elucidated based on spectroscopic analysis and quantum chemical calculations of 13C NMR data. • Compounds 6 and 9 showed NO inhibitory effects with IC 50 values of 9.3 and 10.6 μM, respectively. [ABSTRACT FROM AUTHOR]

Pyrethroids are a class of highly effective, broad-spectrum, less toxic, biodegradable synthetic pesticides. However, despite the extremely wide application of pyrethroids, there are many problems, such as insecticide resistance, lethal/sub-lethal toxicity to mammals, aquatic organisms or other beneficial organisms. The objectives of this review were to cover the main structures, synthesis, steroisomers, mechanisms of action, anti-mosquito activities, resistance, photodegradation and toxicities of pyrethroids. That was to provide a reference for synthesizing or screening novel pyrethroids with low insecticide resistance and low toxicity to beneficial organisms, evaluating the environmental pollution of pyrethroids and its metabolites. Besides, pyrethroids are mainly used for the control of vectors such as insects, and the non-target organisms are mammals, aquatic organisms etc. While maintaining the insecticidal activity is important, its toxic effects on non-target organisms should be also considered. Pyrethroid resistance is present not only in insect mosquitoes but also in environmental microorganisms, which results in anti-pyrethroids resistance (APR) strains. Besides, photodegradation product dibenzofurans is harmful to mammals and environment. Additionally, pyrethroid metabolites may have higher hormonal interference than the parents. Particularly, delivery of pyrethroids in nanoform can reduce the discharge of more toxic substances (such as organic solvents, etc.) to the environment. Image 1 • The resistance, photodegradation, toxicity, mechanisms of pyrethroids is reviewed. • Pyrethroid resistance in microbes can lead to anti-pyrethroids resistance strains. • Pyrethroid metabolites may have higher hormonal interference than the parents. • Photodegradation product dibenzofurans is harmful to mammals and the environment. • Delivery of pyrethroids in nanoform reduces the discharge of more toxic substances. [ABSTRACT FROM AUTHOR]

• Dual immunoassays based on PbNPs was developed for GCA detection. • Anti-GCA mAb-conjugated PbNPs were used as a signal indicator. • The developed assay demonstrated good recovery and precision. • The method was sensitive, rapid, and handy for on-site detection samples. • The limit of detection was 22 ng/mL and detection can be completed within 5 min. Prussian Blue nanoparticles (PBNPs) were utilized in a lateral flow immunoassay (LFA) and in an indirect competitive nanozyme-linked immunosorbent assay (icELISA), respectively, for their intense blue color and peroxidase (POx) -like activity. The PBNPs with good POx-like activity was linked to the antibody. Under the optimal parameters, both the PBNP-icELISA and PBNP-LFA perform very well. The icELISA has an IC50 value of 190 ng/mL, the working range extends from 29 to 1200 ng/mL, and the limit of detection is 22 ng/mL. The visual cut-off limit is 10 ng/mL. The dual immunoassay was used to quantify glycocholic acid in spiked human urine. Excellent recoveries and correlation between the two methods were observed. [ABSTRACT FROM AUTHOR]