Pneumolysin as a target for new therapies against pneumococcal infections: A systematic review.

Background: This systematic review evaluates pneumolysin (PLY) as a target for new treatments against pneumococcal infections. Pneumolysin is one of the main virulence factors produced by all types of pneumococci. This toxin (53 kDa) is a highly conserved protein that binds to cholesterol in eukaryotic cells, forming pores that lead to cell destruction.

Electrocatalytic Palladium Nanoclusters as Versatile Indicators of Bioassays: Rapid Electroanalytical Detection of SARS-CoV-2 by Reverse Transcription Loop-Mediated Isothermal Amplification.

Quantitative polymerase chain reaction (qPCR) is considered the gold standard for pathogen detection. However, improvement is still required, especially regarding the possibilities of decentralization. Apart from other reasons, infectious diseases demand on-site analysis to avoid pathogen spreading and increase treatment efficacy.

Electrochemical Detection for Isothermal Loop-Mediated Amplification of Pneumolysin Gene of Based on the Oxidation of Phenol Red Indicator.

A highly sensitive electrochemical methodology for end-point detection of loop-mediated isothermal nucleic acid amplification reactions was developed. It is based on the oxidation process of phenol red (PR), commonly used as a visual indicator. The dependence of its redox process on pH, which changes during amplification, allows performing quantitative measurements.

Review: Presence, distribution and current pesticides used in Spanish agricultural practices.

To guarantee an adequate food supply for the world's growing population, intensive agriculture is necessary to ensure efficient food production. The use of pesticides helps maintain maximum productivity in intensive agriculture by minimizing crop losses due to pests. However, pesticide contamination of surface waters constitutes a major problem as they are resistant to degradation and soluble enough to be transported in water.

Magnetic Nanoclusters Increase the Sensitivity of Lateral Flow Immunoassays for Protein Detection: Application to Pneumolysin as a Biomarker for .

Lateral flow immunoassays for detecting biomarkers in body fluids are simple, quick, inexpensive point-of-care tests widely used in disease surveillance, such as during the coronavirus disease 2019 (COVID-19) pandemic. Improvements in sensitivity would increase their utility in healthcare, food safety, and environmental control. Recently, biofunctional magnetic nanoclusters have been used to selectively label target proteins, which allows their detection and quantification with a magneto-inductive sensor.

Gram-Positive Pneumonia: Possibilities Offered by Phage Therapy.

Pneumonia is an acute pulmonary infection whose high hospitalization and mortality rates can, on occasion, bring healthcare systems to the brink of collapse. Both viral and bacterial pneumonia are uncovering many gaps in our understanding of host-pathogen interactions, and are testing the effectiveness of the currently available antimicrobial strategies. In the case of bacterial pneumonia, the main challenge is antibiotic resistance, which is only expected to increase during the current pandemic due to the widespread use of antibiotics to prevent secondary infections in COVID-19 patients.

Developing Diagnostic and Therapeutic Approaches to Bacterial Infections for a New Era: Implications of Globalization.

In just a few months, the current coronavirus pandemic has exposed the need for a more global approach to human health. Indeed, the quick spread of infectious diseases and their unpredictable consequences, in terms of human lives and economic losses, will require a change in our strategy, both at the clinical and the research level. Ultimately, we should be ready to fight against infectious diseases affecting a huge number of people in different parts of the world.

Identification of Pneumococcal Serotypes by PCR-Restriction Fragment Length Polymorphism.

shows more than 90 capsular serotypes that can be distinguished by their reactivity against antisera. The main objective of this work was the development of a molecular method for serotyping without the use of antisera. A computer program containing an algorithm was used to search in a database for potentially useful enzymes for Restriction Fragment Length Polymorphism-RFLP typing, in order to maximize the discrimination between different serotypes.

Protein Expression Analysis by Western Blot and Protein-Protein Interactions.

Western blot analysis is widely used for detecting protein expression, analysis of protein-protein interactions, and searching for new biomarkers. Also, it is a diagnostic tool used for detection of human diseases and microorganism infections.Some Streptococcus pneumoniae proteins are important virulence factors and a few of them are diagnostic markers.

Performance of a pneumolysin enzyme-linked immunosorbent assay for diagnosis of pneumococcal infections.

A pneumolysin-specific enzyme-linked immunosorbent assay (PLY-ELISA) for the detection of pneumolysin in urine was developed and evaluated in comparison with the commercially available Binax Now Streptococcus pneumoniae test (Binax, Portland, ME) for the diagnosis of pneumococcal infections. Assay sensitivity was evaluated using urine from 108 patients with culture-confirmed pneumococcal infections. In adults, the sensitivity and specificity of the PLY-ELISA were 56.

Protection against pneumococcal pneumonia in mice by monoclonal antibodies to pneumolysin.

Pneumolysin (PLY) is an important virulence factor of Streptococcus pneumoniae. We examined the ability of three murine monoclonal antibodies (MAbs) to PLY (PLY-4, PLY-5, and PLY-7) to affect the course of pneumococcal pneumonia in mice. The intravenous administration of antibodies PLY-4 and PLY-7 protected the mice from the lethal effect of the purified toxin.

Immunodetection of pneumolysin in human urine by ELISA.

An ELISA test has been employed for the detection of pneumolysin (PLY) in urine from 14 pneumococcal pneumonia patients and from 11 healthy adult volunteers. The urines of all the 11 healthy adult volunteers developed signals around the mean of the blanks, whereas all the pneumococcal pneumonia patient urines rendered signals at least five times this mean. Chemiluminescent Western blot analyses of these urines, carried out with the PLY-specific rabbit polyclonal IgG preparation used in ELISA, were negative.