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Infectious diseases caused by antibiotic-resistant bacterial (ARB) pathogens are a serious threat to human and animal health. The active surveillance of ARB using an integrated one-health approach can help to reduce the emergence and spread of ARB, reduce the associated economic impact, and guide antimicrobial stewardship programs. Wastewater surveillance (WWS) of ARB provides composite samples for a total population, with easy access to the mixed community microbiome. This concept is emerging rapidly, but the clinical utility, sensitivity, and uniformity of WWS of ARB remain poorly understood especially in relation to clinical evidence in sewershed communities. Here, we systematically searched the literature to identify studies that have compared findings from WWS of ARB and antibiotic resistance genes (ARG) with clinical evidence in parallel, thereby evaluating how likely WWS of ARB and ARG can relate to the clinical cases in communities. Initially, 2,235 articles were obtained using the primary search keywords, and 1,219 articles remained after de-duplication. Among these, 35 articles fulfilled the search criteria, and an additional 13 relevant articles were included by searching references in the primary literature. Among the 48 included papers, 34 studies used a culture-based method, followed by 11 metagenomics, and three PCR-based methods. A total of 28 out of 48 included studies were conducted at the single sewershed level, eight studies involved several countries, seven studies were conducted at national or regional scales, and five at hospital levels. Our review revealed that the performance of WWS of ARB pathogens has been evaluated more frequently for Escherichia coli, Enterococcus spp., and other members of the family Enterobacteriaceae, but has not been uniformly tested for all ARB pathogens. Many wastewater-based ARB studies comparing the findings with clinical evidence were conducted to evaluate the public health risk but not to relate with clinical evidence and to evaluate the performance of WWS of ARB. Indeed, relating WWS of ARB with clinical evidence in a sewershed is not straightforward, as the source of ARB in wastewater cannot be only from symptomatic human individuals but can also be from asymptomatic carriers as well as from animal sources. Further, the varying fates of each bacterial species and ARG within the sewerage make the aim of connecting WWS of ARB with clinical evidence more complicated. Therefore, future studies evaluating the performance of many AMR pathogens and their genes for WWS one by one can make the process simpler and the interpretation of results easier. [ABSTRACT FROM AUTHOR]

The microRNA (miRNA) cargo contained in plasma extracellular vesicles (EVs) offers a relatively little explored source of biomarkers for brain diseases that can be obtained noninvasively. Methods to isolate EVs from plasma, however, are still being developed. For EV isolation, it is important to ensure the removal of vesicle-free miRNAs, which account for approximately two-thirds of plasma miRNAs. Membrane particle precipitation-based EV isolation is an appealing method because of the simple protocol and high yield. Here, we evaluated the performance of a precipitation-based method to obtain enriched EV-specific miRNAs from a small volume of rat plasma. We performed size-exclusion chromatography (SEC) on precipitation-isolated EV pellets and whole plasma. The SEC fractions were analysed using Nanoparticle Tracking Analysis (NTA), protein and miRNA concentration assays, and droplet digital polymerase chain reaction for four miRNAs (miR-142-3p, miR-124-3p, miR-23a, miR-122). Precipitation-isolated EVs and selected SEC fractions from the plasma were also analysed with transmission electron microscopy (TEM). Precipitation-based EV isolation co-precipitated 9% to 15% of plasma proteins and 21% to 99% of vesicle-free miRNAs, depending on the individual miRNAs. In addition, the amount of miR-142-3p, found mainly in EV fractions, was decreased in the EV fractions, indicating that part of it was lost during precipitation-based isolation. Western blot and TEM revealed both protein and lipoprotein contamination in the precipitation-isolated EV-pellets. Our findings indicate that a precipitation-based method is not sufficient for purifying plasma EV-contained miRNA cargo. The particle number measured by NTA is high, but this is mostly due to the contaminating lipoproteins. Although a part of the vesicle-free miRNA is removed, vesicle-free miRNA still dominates in plasma EV pellets isolated by the precipitation-based method. [ABSTRACT FROM AUTHOR]

Our objective was to define the chronically altered gene expression signature of traumatic brain injury (TBI-sig), and apply it to discover novel treatments in order to reverse pathologic gene expression or reinforce the expression of recovery-related genes. TBI was induced with lateral fluid-percussion injury in adult male rats. Genome-wide RNA-seq of the perilesional cortex, ipsilateral thalamus and ipsilateral hippocampus was performed at 3 months post-TBI. Data highlighted chronic transcriptional changes, particularly, in the perilesional cortex (4 964 regulated genes) and thalamus (1 966)(FDR < 0.05). Gene set enrichment analysis (GSEA) indicated down-regulation of ion channel and mitochondrial gene sets and upregulation of inflammatory gene sets (GSEA q-value < 0.01). Transcriptomics data were used to design the TBI-sig which was used in LINCS analysis. We identified 18 of 1064 compounds which regulated gene expression in three cell lines with strong connectivity score with TBI-sig. Eleven of these 18 compounds showed a strong connectivity with TBI-sig in neuronal cell lines. Two of 11 compounds (celecobix, sirolimus) were recently shown to have a disease-modifying effect in in vivo animal models of epilepsy. The nine other compounds revealed by the analysis were (BRD-K91844626; BRD-A11009626; NO-ASA; BRD-K55260239; SDZ-NKT-343; STK-661558; BRD-K75971499; ionomycin; desmethylclomipramine). Transcriptomics signatures of the 11 compounds were compared in more details with TBI-sig. IPA analysis of overlapping genes revealed the effects of these compounds on tubulins (Tubb2a, Tubb3, Tubb4b), Nfe2l2, S100a4, Cd44, and Nfkb2, which have been linked to TBI-relevant outcomes, including epileptogenesis and tissue repair. From all compounds revealed by the LINCS analysis, desmetylclomipramine, an active metabolite of antidepressant clomipramine, modulated most of the gene targets considered favorable for the TBI outcome. Our data demonstrate long-lasting transcriptomics changes after TBI in the perilesional cortex and thalamus, suggesting a long-lasting therapeutic window. LINCS analysis predicted that these changes can be modulated by various compounds, some of which are already in clinical use. [ABSTRACT FROM AUTHOR]

Traumatic brain injury (TBI) induces a wide variety of cellular and molecular changes that can continue for days to weeks to months, leading to functional impairments. Currently, there are no pharmacotherapies in clinical use that favorably modify the post-TBI outcome, due in part to limited understanding of the mechanisms of TBI-induced pathologies. Our system biology analysis tested the hypothesis that chronic transcriptomics changes induced by TBI are controlled by altered DNA-methylation in gene promoter areas or by transcription factors. We performed genome-wide methyl binding domain (MBD)-sequencing (seq) and RNA-seq in perilesional, thalamic, and hippocampal tissue sampled at 3 months after TBI induced by lateral fluid percussion in adult male Sprague-Dawley rats. We investigated the regulated molecular networks and mechanisms underlying the chronic regulation, particularly DNA methylation and transcription factors. Finally, we identified compounds that modulate the transcriptomics changes and could be repurposed to improve recovery. Unexpectedly, DNA methylation was not a major regulator of chronic post-TBI transcriptomics changes. On the other hand, the transcription factors Cebpd, Pax6, Spi1, and Tp73 were upregulated at 3 months after TBI (False discovery rate < 0.05), which was validated using digital droplet polymerase chain reaction. Transcription regulatory network analysis revealed that these transcription factors regulate apoptosis, inflammation, and microglia, which are well-known contributors to secondary damage after TBI. Library of Integrated Network-based Cellular Signatures (LINCS) analysis identified 118 pharmacotherapies that regulate the expression of Cebpd, Pax6, Spi1, and Tp73. Of these, the antidepressant and/or antipsychotic compounds trimipramine, rolipramine, fluspirilene, and chlorpromazine, as well as the anti-cancer therapies pimasertib, tamoxifen, and vorinostat were strong regulators of the identified transcription factors, suggesting their potential to modulate the regulated transcriptomics networks to improve post-TBI recovery. [ABSTRACT FROM AUTHOR]

Background: Many countries have applied the wastewater surveillance of the COVID-19 pandemic to their national public health monitoring measures. The most used methods for detecting SARS-CoV-2 in wastewater are quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR) and reverse transcriptase-droplet digital polymerase chain reaction (RT-ddPCR). Previous comparison studies have produced conflicting results, thus more research on the subject is required., Objective: This study aims to compare RT-qPCR and RT-ddPCR for detecting SARS-CoV-2 in wastewater. It also aimed to investigate the effect of changes in the analytical pipeline, including the RNA extraction kit, RT-PCR kit, and target gene assay, on the results. Another aim was to find a detection method for low-resource settings., Methods: We compared 2 RT-qPCR kits, TaqMan RT-qPCR and QuantiTect RT-qPCR, and RT-ddPCR based on sensitivity, positivity rates, variability, and correlation of SARS-CoV-2 gene copy numbers in wastewater to the incidence of COVID-19. Furthermore, we compared 2 RNA extraction methods, column- and magnetic-bead-based. In addition, we assessed 2 target gene assays for RT-qPCR, N1 and N2, and 2 target gene assays for ddPCR N1 and E. Reverse transcription strand invasion-based amplification (RT-SIBA) was used to detect SARS-CoV-2 from wastewater qualitatively., Results: Our results indicated that the most sensitive method to detect SARS-CoV-2 in wastewater was RT-ddPCR. It had the highest positivity rate (26/30), and its limit of detection was the lowest (0.06 gene copies/µL). However, we obtained the best correlation between COVID-19 incidence and SARS-CoV-2 gene copy number in wastewater using TaqMan RT-qPCR (correlation coefficient [CC]=0.697, P<.001). We found a significant difference in sensitivity between the TaqMan RT-qPCR kit and the QuantiTect RT-qPCR kit, the first having a significantly lower limit of detection and a higher positivity rate than the latter. Furthermore, the N1 target gene assay was the most sensitive for both RT-qPCR kits, while no significant difference was found between the gene targets using RT-ddPCR. In addition, the use of different RNA extraction kits affected the result when the TaqMan RT-qPCR kit was used. RT-SIBA was able to detect SARS-CoV-2 RNA in wastewater., Conclusions: As our study, as well as most of the previous studies, has shown RT-ddPCR to be more sensitive than RT-qPCR, its use in the wastewater surveillance of SARS-CoV-2 should be considered, especially if the amount of SARS-CoV-2 circulating in the population was low. All the analysis steps must be optimized for wastewater surveillance as our study showed that all the analysis steps including the compatibility of the RNA extraction, the RT-PCR kit, and the target gene assay influence the results. In addition, our study showed that RT-SIBA could be used to detect SARS-CoV-2 in wastewater if a qualitative result is sufficient., (©Annika Länsivaara, Kirsi-Maarit Lehto, Rafiqul Hyder, Erja Sinikka Janhonen, Anssi Lipponen, Annamari Heikinheimo, Tarja Pitkänen, Sami Oikarinen, WastPan Study Group. Originally published in JMIR Public Health and Surveillance (https://publichealth.jmir.org), 19.08.2024.)