RESUMO
The rapid and accurate diagnosis of meningitis is critical for preventing severe complications and fatalities. This study addresses the need for accessible diagnostics in the absence of specialized equipment by developing a novel diagnostic assay. The assay utilizes dual-priming isothermal amplification (DAMP) with unique internal primers to significantly reduce non-specificity. For fluorescence detection, the dye was selected among Brilliant Green, Thioflavin T, and dsGreen. Brilliant Green is preferred for this assay due to its availability, high fluorescence level, and optimal sample-to-background (S/B) ratio. The assay was developed for the detection of the primary causative agents of meningitis (Haemophilus influenzae, Neisseria meningitidis, and Streptococcus pneumoniae), and tested on clinical samples. The developed method demonstrated high specificity, no false positives, sensitivity comparable to that of loop-mediated isothermal amplification (LAMP), and a high S/B ratio. This versatile assay can be utilized as a standalone test or an integrated assay into point-of-care systems for rapid and reliable pathogen detection.
Assuntos
Haemophilus influenzae , Meningites Bacterianas , Técnicas de Diagnóstico Molecular , Neisseria meningitidis , Técnicas de Amplificação de Ácido Nucleico , Streptococcus pneumoniae , Neisseria meningitidis/genética , Neisseria meningitidis/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico/métodos , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/isolamento & purificação , Humanos , Haemophilus influenzae/genética , Haemophilus influenzae/isolamento & purificação , Meningites Bacterianas/diagnóstico , Meningites Bacterianas/microbiologia , Técnicas de Diagnóstico Molecular/métodos , Sensibilidade e EspecificidadeRESUMO
Bacterial infection is a major problem with diabetic wounds that may result in nonhealing chronic ulcers. Here, we report an approach to antibacterial hydrogel dressings for enhanced treatment of infected skin wounds. A fibrous hydrogel was derived from cellulose nanocrystals that were modified with dopamine and cross-linked with gelatin. The hydrogel was loaded with gentamicin, an antibiotic drug. Enhanced antibacterial hydrogel performance resulted from (i) a highly specific sequestration of Fe3+ ions (much needed by bacteria) from the wound exudate and (ii) a dynamic exchange between gentamicin released from the hydrogel and Fe3+ ions withdrawn from the wound exudate. Such exchange was possible due to the high value of the binding constant of Fe3+ ions to dopamine. The hydrogel did not affect the metabolic activity of skin-related cells and showed enhanced antibacterial performance against common wound pathogens such as S. aureus and P. aeruginosa. Furthermore, it promoted healing of infected diabetic wounds due to a synergistic antibacterial effect providing the dynamic exchange between Fe3+ ions and gentamicin. This work provides a strategy for the design of dual-function wound dressings, with both starving and killing bacteria and enhanced wound healing performance.