6 research outputs found
Identifying Microbial Biomarkers for Early Detection and Health Diagnosis of Harmful Algal Blooms in Freshwater Lakes
Harmful algal blooms (HABs) have been a very common phenomenon in the last few decades, intensified by global warming, eutrophication, and increased CO2 levels. We hypothesized that biological and chemical parameters will be available allowing early detection of HABs in coherence with microbial signatures, where the health status of the HABs could be indicated by lysis of cyanobacterial cells and release of intracellular materials. Using multi-omics and quantitative real-time PCR, we investigated applicability of microbial signatures as a prognostic tool towards determining bloom health in two Ohio lakes, Lake Erie (LE) and Grand Lake St. Marys (SM), by assessing with chemical data. Different cyanobacterial species dominated algal blooms at LE (Synechococcus and Microcystis) and SM (Dolichospermum and Planktothrix) in the year 2021. Unbound phycocyanin levels were positively correlated with the quantity of cyanobacterial 16S rRNA genes in both LE and SM, with varied strength of correlations, indicating unhealthy cyanobacterial cells being present during the bloom. Genera Pseudomonas and Sediminibacterium as well as the phylum Verrucomicrobia appeared as potential microbial signatures when investigated with relative abundance of cyanobacteria. These signatures are promising to be established and validated as biomarkers for early detection of HABs while integrated with functional gene quantification
Biomarkers of endothelial dysfunction predict sepsis mortality in young infants: a matched case-control study
Abstract
Background
Reducing death due to neonatal sepsis is a global health priority, however there are limited tools to facilitate early recognition and treatment. We hypothesized that measuring circulating biomarkers of endothelial function and integrity (i.e. Angiopoietin-Tie2 axis) would identify young infants with sepsis and predict their clinical outcome.
Methods
We conducted a matched case-control (1:3) study of 98 young infants aged 0–59 days of life presenting to a referral hospital in Bangladesh with suspected sepsis. Plasma levels of Ang-1, Ang-2, sICAM-1, and sVCAM-1 concentrations were measured at admission. The primary outcome was mortality (n = 18); the secondary outcome was bacteremia (n = 10).
Results
Ang-2 concentrations at presentation were higher among infants who subsequently died of sepsis compared to survivors (aOR 2.50, p = 0.024). Compared to surviving control infants, the Ang-2:Ang-1 ratio was higher among infants who died (aOR 2.29, p = 0.016) and in infants with bacteremia (aOR 5.72, p = 0.041), and there was an increased odds of death across Ang-2:Ang-1 ratio tertiles (aOR 4.82, p = 0.013).
Conclusions
This study provides new evidence linking the Angiopoietin-Tie2 pathway with mortality and bacteremia in young infants with suspected sepsis. If validated in additional studies, markers of the angiopoietin-Tie2 axis may have clinical utility in risk stratification of infants with suspected sepsis
The impacts of different types of commercial algaecide products on cyanobacteria control and intracellular organic matter releases
Cyanobacterial harmful algal blooms (cHABs) pose great challenges to public water systems when producing safe drinking water. Applying algaecide is one of the most common methods to control the cHABs in source waters, however, it can cause cell lyses and release the intracellular organic matter (IOM) and the toxins, which are difficult to remove in public drinking water systems with conventional drinking water treatment processes. In this study, we evaluated four commercial algaecide products (two copper-based and two peroxide-based) and assessed the impact of algaecide treatment on cyanobacteria cell removal and the release of IOM and toxins. The optimal dose and the treatment time of each product were determined using both granular (Microcystis aeruginosa) and filamentous (Planktotrix agardhii) cyanobacteria. A Parallel Factor Analysis (PARAFAC) model was built using collected Excitation-Emission Matrix (EEM) spectra from collected samples under different algaecide treatment time and doses to characterize and quantify the release of IOM during the treatment. The obtained results may help public water systems better control HABs without causing adverse impacts on finished water quality
SARS-CoV-2 Monitoring in Wastewater Reveals Novel Variants and Biomarkers of Infection
Wastewater-based epidemiology (WBE) is a popular tool for the early indication of community spread of infectious diseases. WBE emerged as an effective tool during the COVID-19 pandemic and has provided meaningful information to minimize the spread of infection. Here, we present a combination of analyses using the correlation of viral gene copies with clinical cases, sequencing of wastewater-derived RNA for the viral mutants, and correlative analyses of the viral gene copies with the bacterial biomarkers. Our study provides a unique platform for potentially using the WBE-derived results to predict the spread of COVID-19 and the emergence of new variants of concern. Further, we observed a strong correlation between the presence of SARS-CoV-2 and changes in the microbial community of wastewater, particularly the significant changes in bacterial genera belonging to the families of Lachnospiraceae and Actinomycetaceae. Our study shows that microbial biomarkers could be utilized as prediction tools for future infectious disease surveillance and outbreak responses. Overall, our comprehensive analyses of viral spread, variants, and novel bacterial biomarkers will add significantly to the growing body of literature on WBE and COVID-19
Additional file 1: of Biomarkers of endothelial dysfunction predict sepsis mortality in young infants: a matched case-control study
Table S1. Blood culture isolates from bacteremic infants. Bacterial isolates from blood cultures obtained by venipuncture on admission of septic young infants age < 59 days to a pediatric facility in Sylhet, Bangladesh. (DOCX 16 kb