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The presence of antibiotic residues in cow's milk entails high risk for consumers, the dairy industry, and the environment. Therefore, the development of highly specific and sensitive screening tools for the rapid and cost-effective identification of traces of these compounds is urgently needed. A multiplexed screening platform utilizing DNA-directed immobilization (DDI) was developed aiming to detect three classes of antibiotic residues (fluoroquinolones, sulfonamides, and tylosin) prevalently found in milk. Throughout this work, each oligonucleotide sequence was conjugated to a different hapten molecule, while the three complementary strands were immobilized in 24 independent microarray chips on a single glass slide. First, the array was incubated with the pool of hapten-oligonucleotide conjugate site encoded the signal through DNA hybridization. Next, commercial milk samples were incubated with the cocktail of monoclonal antibodies following a secondary fluorophore-labeled antibody which was required for fluorescent readout. Direct sample detection was achieved in milk diluting 20 times in assay buffer. The limits of detection (LODs) reached were 1.43 µg kg -1 , 1.67 µg kg -1 , and 0.89 µg kg -1 for TYLA, STZ, and CIP, respectively, which represented in raw milk 7.15 µg kg -1 , 8.35 µg kg -1 , and 4.45 µg kg -1 for TYLA, STZ, and CIP, respectively, that are below the EU regulatory limits. Cross-reactivity profiles were evaluated against the family of structurally related antibiotics in order to demonstrate the capability to detect antibiotics from the same family of compounds. A pre-validation study was performed by spiking 20 blind samples above and below the maximum residue limits established by the EU guidelines. The system was successfully implemented towards randomized sample classification as compliant or non-compliant. The proposed DDI-based immunoarray provides a fast and cost-effective alternative to obtain semi-quantitative information about the presence of three veterinary residues simultaneously in milk samples., (© 2024. The Author(s).)

Purpose: To analyze the recovery course of foveal microstructures in eyes with nonsurgical healing of full-thickness macular hole (FTMH)., Methods: By serial OCT scans, the temporal healing sequences were analyzed in ocular trauma, vitreomacular traction (VMT), cystoid macular edema (CME), and the remaining group. We evaluated correlations between the final best-corrected spectacle visual acuity and reconstruction time of external limiting membrane (ELM), and inner segment/outer segment (IS/OS)., Results: The healing (mean±standard deviation in months) most involved fusion at the level of the outer nuclear layer (ONL) (6.3±10.5) followed by restoration of ELM (9.1±13.8), and lastly, by IS/OS regeneration (13.1±19.5). In severe blunt ocular trauma, healing was fast and involved subretinal zipper glue-like reapposition with resulting outer retinal atrophy. Best spectacle-corrected visual acuity correlated with normalization of the clivus (p=0.012), faster ELM (p=0.006), and IS/OS reconstitution (p=0.024). Recurrence of FTMH occurred when the healing was halted (3 eyes) or was aberrant by lamellar hole epiretinal proliferation (LHEP) (3 eyes) or by the persistence of VMT (1 eye)., Conclusion: Recovery sequences proceeded from the ONL to the deeper layers with BCVA correlating absolutely and temporally with the restoration of outer retinal layer integrity., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Purpose: The aim of the present investigation is to study the relationship of ventricular global longitudinal strain (GLS) and ultrasound lung comets (ULC) formation to establish a link between extravascular pulmonary water formation and cardiac contractile dysfunction., Methods: This is a prospective observational study including 14 active military divers. The subjects performed two sea dives of 120 min each with a semi-closed SCUBA circuit at 10 m depth. Divers were examined at baseline, 15 min (D1) and 60 min (D2) after diving. The evaluation included pulmonary and cardiac echography (including speckle tracking techniques). Blood samples were drawn at baseline and after diving, assessing hs-TnT and Endothelin-1., Results: ULC were detected in 9 (64.2%) and 8 (57.1%) of the subjects after D1 and D2 respectively. No differences were found in right and left ventricular GLS after both immersions (RV: Baseline:  - 17.9 4.9 vs. D1:  - 17.2 6.5 and D2:  - 16.7 5.8 s -1 ; p = 0.757 and p = 0.529; LV: Baseline:  - 17.0 2.3 vs. D1:  - 17.4 2.1 and D2:  - 16.9 2.2 s -1 ; p = 0.546 and p = 0.783). However, a decrease in atrial longitudinal strain parameters have been detected after diving (RA: Baseline: 35.5 9.2 vs. D1: 30.3 12.8 and D2: 30.7 13.0 s -1 ; p = 0.088 and p = 0.063; LA: Baseline: 39.0 10.0 vs. D1: 31.6 6.1 and D2: 32.4 10.6 s -1 ; p = 0.019 and p = 0.054)., Conclusion: In the present study, no ventricular contractile dysfunction was observed. However, increase pulmonary vasoconstriction markers were present after diving., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

A fluorescent quantum dot-based antibody array, used in sandwich format, has been developed to detect Escherichia coli O157:H7. Numerous parameters such as solid support, optimal concentration of immunoreagents, blocking reagents, and assay time were optimized for array construction. Quantum dot-conjugated anti-IgG was used as the detecting system. The array allows the detection of E. coli O157:H7 at concentrations below 10 CFU mL(-1) without sample enrichment, exhibiting an increase of three orders of magnitude in the limit of detection compared to ELISA. The interference caused by Gram (+) and Gram (-) bacteria was negligible at low concentrations of bacteria.