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Effective food safety monitoring requires a multi-step approach from farm to fork, involving different methods, ranging from convenient screening devices to sophisticated laboratory confirmatory testing. However, sample transportation to routine laboratories is time-consuming and expensive. Simplified on-site sampling followed by laboratory analysis offers a potential solution. Dried blood spot (DBS) cards ensure stability and ease of sample transportation and are used in clinical testing. However, the applicability of such an approach could be broader and include the storage of dried extract from more complex (solid) matrices. Therefore, a simplified approach is presented here, using DBS cards for on-site sampling and subsequent laboratory confirmation for food contaminants. To achieve this, an analytical tool (Smartcard) was designed using 3D-printing technology. As a proof of concept, the approach was applied to detect the pesticide fipronil, which is widely used in ornamental flower production to limit pests and on poultry farms. The Smartcard can securely store the sample extracts on a DBS card (dried extract spot (DExS) card), incorporate the lateral flow immunoassay (LFIA) and immediately provide an estimate of contamination levels. After simplified in-syringe extraction of the sample, the LFIA allows direct screening of fipronil (half maximum inhibitory concentration of 6.5 µg/l with calibration standards), and the same sample extract can be directly applied to the DExS card for storage and transport to the laboratory, where analyte re-extraction and instrumental analysis is performed using ultra high-pressure liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) detecting fipronil down to 0.8 µg/kg., Competing Interests: Declarations Competing interests The authors declare no competing interests., (© 2024. The Author(s).)

Hepcidin regulates iron metabolism by inhibiting intestinal iron absorption and iron release from iron stores. In addition to iron overload, inflammatory conditions also up-regulate hepcidin synthesis, which may serve as an antimicrobial defense by reducing iron availability to the invading microbes. The purpose of this study is to test this hypothesis in human patients by determining serum hepcidin concentration by enzyme linked immunosorbent assay (ELISA) in healthy blood donors ( n = 60) and patients hospitalized because of bacteremia ( n = 50), before (day 0) and after seven days (day 7) of appropriate antibiotic treatment. Serum hepcidin was significantly increased in patients with bacteremia, both at day 0 and at day 7, compared to healthy controls. However, there was significant reduction of serum hepcidin after 7-day treatment, in concert with changes in serum C-reactive protein (CRP). The hepcidin changes were similar for both Gram-negative and Gram-positive single infection cases, while CRP was significantly reduced only in the former. In contrast to hepcidin, the levels of serum ferritin in the patients remained high after treatment, irrespective of infection type. These data confirm the stimulation of hepcidin secretion in human subjects upon different types of systemic microbial infection and suggest that hepcidin is a more sensitive and treatment-responsive acute-phase marker than ferritin in bacteremia, which needs to be explored with bigger-sized and better-matched patient cohorts.

The discovery of Acanthamoeba polyphaga mimivirus in 2003 using the free-living amoeba Acanthamoeba polyphaga caused a paradigm shift in the virology field. Twelve years later, using another amoeba as a host, i.e., Vermamoeba vermiformis , novel isolates of giant viruses have been discovered. This amoeba-virus relationship led scientists to study the evolution of giant viruses and explore the origins of eukaryotes. The purpose of this article is to review all the giant viruses that have been isolated from Vermamoeba vermiformis , compare their genomic features, and report the influence of these viruses on the cell cycle of their amoebal host. To date, viruses putatively belonging to eight different viral taxa have been described: 7 are lytic and 1 is non-lytic. The comparison of giant viruses infecting Vermamoeba vermiformis has suggested three homogenous groups according to their size, the replication time inside the host cell, and the number of encoding tRNAs. This approach is an attempt at determining the evolutionary origins and trajectories of the virus; therefore, more giant viruses infecting Vermamoeba must be discovered and studied to create a comprehensive knowledge on these intriguing biological entities., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Geballa-Koukoulas, La Scola, Blanc and Andreani.)

The hypoxia-inducible factor HIF-1 is essential for oxygen homeostasis. Despite its well-understood oxygen-dependent expression, regulation of its transcriptional activity remains unclear. We show that phosphorylation by extracellular signal-regulated kinases1/2 (ERK1/2), in addition to promoting HIF-1α nuclear accumulation, also enhances its interaction with chromatin and stimulates direct binding to nucleophosmin (NPM1), a histone chaperone and chromatin remodeler. NPM1 is required for phosphorylation-dependent recruitment of HIF-1 to hypoxia response elements, its interaction with acetylated histones, and high expression of HIF-1 target genes under hypoxia. Transcriptome analysis revealed a significant number of hypoxia-related genes commonly regulated by NPM1 and HIF-1. These NPM1/HIF-1α co-upregulated genes are enriched in three different cancer types, and their expression correlates with hypoxic tumor status and worse patient prognosis. In concert, silencing of NPM1 expression or disruption of its association with HIF-1α inhibits metabolic adaptation of cancer cells and triggers apoptotic death upon hypoxia. We suggest that ERK-mediated phosphorylation of HIF-1α regulates its physical interaction with NPM1, which is essential for the productive association of HIF-1 with hypoxia target genes and their optimal transcriptional activation, required for survival under low oxygen or tumor growth., (© 2021 The Authors. Molecular Oncology published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.)

Acanthamoeba castellanii is an amoeba host that was used to isolate a novel strain named pacmanvirus S19. This isolate is the second strain reported and belongs to the extended Asfarviridae family. Pacmanvirus S19 harbors a 418,588-bp genome, with a GC content of 33.20%, which encodes 444 predicted proteins and a single Ile-tRNA.

Kaumoebavirus infects the amoeba Vermamoeba vermiformis and has recently been described as a distant relative of the African swine fever virus. To characterize the diversity and evolution of this novel viral genus, we report here on the isolation and genome sequencing of a second strain of Kaumoebavirus , namely LCC10. Detailed analysis of the sequencing data suggested that its 362-Kb genome is linear with covalently closed hairpin termini, so that DNA forms a single continuous polynucleotide chain. Comparative genomic analysis indicated that although the two sequenced Kaumoebavirus strains share extensive gene collinearity, 180 predicted genes were either gained or lost in only one genome. As already observed in another distant relative, i.e., Faustovirus , which infects the same host, the center and extremities of the Kaumoebavirus genome exhibited a higher rate of sequence divergence and the major capsid protein gene was colonized by type-I introns. A possible role of the Vermamoeba host in the genesis of these evolutionary traits is hypothesized. The Kaumoebavirus genome exhibited a significant gene strand bias over the two-third of genome length, a feature not seen in the other members of the "extended Asfarviridae " clade. We suggest that this gene strand bias was induced by a putative single origin of DNA replication located near the genome extremity that imparted a selective force favoring the genes positioned on the leading strand.

Faustovirus is a recently discovered genus of large DNA virus infecting the amoeba Vermamoeba vermiformis , which is phylogenetically related to Asfarviridae. To better understand the diversity and evolution of this viral group, we sequenced six novel Faustovirus strains, mined published metagenomic datasets and performed a comparative genomic analysis. Genomic sequences revealed three consistent phylogenetic groups, within which genetic diversity was moderate. The comparison of the major capsid protein (MCP) genes unveiled between 13 and 18 type-I introns that likely evolved through a still-active birth and death process mediated by intron-encoded homing endonucleases that began before the Faustovirus radiation. Genome-wide alignments indicated that despite genomes retaining high levels of gene collinearity, the central region containing the MCP gene together with the extremities of the chromosomes evolved at a faster rate due to increased indel accumulation and local rearrangements. The fluctuation of the nucleotide composition along the Faustovirus (FV) genomes is mostly imprinted by the consistent nucleotide bias of coding sequences and provided no evidence for a single DNA replication origin like in circular bacterial genomes.

Information on drug transfer into the breast milk is essential to protect the infant from undesirable adverse effects of maternal consumption of drugs and to allow effective pharmacological treatment of breastfeeding mothers. Metronidazole and fluconazole are two drugs frequently used in nursing women to treat various infections, thus questioning infant's safety due to drug exposure through breast milk. In this article a porous graphitized carbon LC/ESI-MS assay was developed for the quantitation of metronidazole and fluconazole in breast milk and human plasma. The assay was based on the use of 150 μL of biological samples, following acetonitrile precipitation of proteins and filtration that enabled injection into the LC/ESI-MS system. All analytes and the internal standard, ropinirole, were separated by using a porous graphitized carbon analytical column (150 × 2.1 mm i.d., particle size 5 μm) with isocratic elution. The mobile phase consists of 55% acetonitrile in water acidified with 0.1% concentrated formic acid and pumped at a flow rate of 0.25 mL min -1 . The assay was linear over a concentration range of 0.1 to 15 μg mL -1 for all analytes in both biological samples. Intermediate precision was found to be <8.4% over the tested concentration ranges. A run time of <5 min for each sample made it possible to analyze a large number of biological samples per day. The method is the first reported application for the analysis of metronidazole and fluconazole in both breast milk and human plasma and it can be used to support a wide range of clinical studies., (Copyright © 2018 Elsevier B.V. All rights reserved.)