Publications by authors named "Malo D"

Ultraviolet radiation's germicidal efficacy depends on several parameters, including wavelength, radiant exposure, microbial physiology, biological matrices, and surfaces. In this work, several ultraviolet radiation sources (a low-pressure mercury lamp, a KrCl excimer, and four UV LEDs) emitting continuous or pulsed irradiation were compared. The greatest log reductions in E.

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Article Synopsis
  • The study discusses a rare lung disease in nine children linked to a genetic deficiency of the CCR2 receptor, leading to conditions like pulmonary alveolar proteinosis (PAP) and increased vulnerability to infections.
  • This deficiency is characterized by loss-of-function variants, affecting the migration and signaling of immune cells, particularly monocytes, due to a lack of response to CCL-2, a chemokine essential for these processes.
  • Elevated levels of CCL-2 in the blood serve as a diagnostic marker for identifying children with unexplained respiratory issues or recurrent infections, indicating the importance of CCR2 in lung health and immune response.
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Rheumatoid arthritis is a chronic and systemic inflammatory disease that affects approximately 1% of the world's population and is characterised by joint inflammation, the destruction of articular cartilage and bone, and many potentially life-threatening extraarticular manifestations. B lymphocytes play a central role in the pathology of rheumatoid arthritis as the precursors of autoantibody secreting plasma cells, as highly potent antigen-presenting cells, and as a source of various inflammatory cytokines, however, the effects of rheumatoid arthritis on B lymphocyte development remain poorly understood. Here, we analyse B lymphocyte development in murine models of rheumatoid arthritis, quantifying all the subsets of B cell precursors in the bone marrow and splenic B cells using flow cytometry.

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Germanium-tin nanoparticles are promising materials for near- and mid-infrared photonics thanks to their tunable optical properties and compatibility with silicon technology. This work proposes modifying the spark discharge method to produce Ge/Sn aerosol nanoparticles during the simultaneous erosion of germanium and tin electrodes. Since tin and germanium have a significant difference in the potential for electrical erosion, an electrical circuit damped for one period was developed to ensure the synthesis of Ge/Sn nanoparticles consisting of independent germanium and tin crystals of different sizes, with the ratio of the atomic fraction of tin to germanium varying from 0.

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Aluminum nanoparticles attract scientific interest as a promising low-cost material with strong plasmon resonance in the ultraviolet region, which can be used in various fields of photonics. In this paper, for the first time, ultraviolet luminescence of zinc oxide nanoparticles in colloid solutions and nanostructure films in the presence of plasmonic aluminum nanoparticles 60 nm in size with a metal core and an aluminum oxide shell were studied. Mixture colloids of ZnO and Al nanoparticles in isopropyl alcohol solution with concentrations from 0.

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The development of the first intermolecular Rh(II)-catalyzed aziridination of olefins using anilines as nonactivated N atom precursors and an iodine(III) reagent as the stoichiometric oxidant is reported. This reaction requires the transfer of an -aryl nitrene fragment from the iminoiodinane intermediate to a Rh(II) carboxylate catalyst; in the absence of a catalyst only diaryldiazene formation was observed. This -aryl aziridination is general and can be successfully realized by using as little as 1 equiv of the olefin.

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  • Salmonella enterica subsp. enterica is a major cause of foodborne infections, particularly linked to fresh fruits and vegetables.
  • The study examined how the virulence of different S. enterica strains affects their survival in the human digestive system using a model that mimics gastrointestinal conditions.
  • Results showed that high-virulence strains survived significantly better than low-virulence strains in the digestive tract, suggesting that specific genes related to acid and bile resistance contribute to their enhanced survival.
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  • - SARS-CoV-2 has genetic diversity that can influence how easily the virus spreads and its ability to evade immunity from natural infections or vaccines.
  • - A study in Colombia identified the B.1.621 lineage of SARS-CoV-2 (a variant of interest) from genome sequencing of samples collected between January and April 2021, revealing several significant mutations in the Spike protein.
  • - The B.1.621 variant showed a rapid increase in prevalence in various regions of Colombia, raising concerns about its potential impact on public health and the effectiveness of existing immunity levels.
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The emergence of multidrug-resistant bacterial strains worldwide has become a serious problem for public health over recent decades. The increase in antimicrobial resistance has been expanding via plasmids as mobile genetic elements encoding antimicrobial resistance (AMR) genes that are transferred vertically and horizontally. This study focuses on , one of the leading foodborne pathogens in industrialized countries.

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Article Synopsis
  • - A study analyzed more than 2,600 serovars of bacteria to explore the links between genetic differences and their ability to cause disease, aiming to create a predictive model for virulence.
  • - Researchers evaluated 35 strains from the SalFoS collection using various infection models, including tests on human cells and mice, to identify signs of virulence and correlate them with genomic data.
  • - Findings revealed significant correlations in virulence predictions based on genomic information, providing a new strategy for assessing risks and monitoring bacterial strains linked to foodborne illnesses.
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is an intracellular bacterium found in the gastrointestinal tract of mammalian, avian, and reptilian hosts. Mouse models have been extensively used to model distinct aspects of human infections and have led to the identification of several host susceptibility genes. We have investigated the susceptibility of Collaborative Cross strains to intravenous infection with serovar Typhimurium as a model of human systemic invasive infection.

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Background: Despite having influenza vaccination policies and programs, countries in the Americas underutilize seasonal influenza vaccine, in part because of insufficient evidence about severe influenza burden. We aimed to estimate the annual burden of influenza-associated respiratory hospitalizations in the Americas.

Methods: Thirty-five countries in the Americas with national influenza surveillance were invited to provide monthly laboratory data and hospital discharges for respiratory illness (International Classification of Diseases 10th edition J codes 0-99) during 2010-2015.

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Salmonella presents a global public health concern. Central to Salmonella pathogenicity is an ability to subvert host defences through strategically targeting host proteins implicated in restricting infection. Therefore, to gain insight into the host-pathogen interactions governing Salmonella infection, we performed an in vivo genome-wide mutagenesis screen to uncover key host defence proteins.

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Article Synopsis
  • Enterobacteriaceae is a diverse group of Gram-negative bacteria, some of which are harmless residents in humans and animals, while others can cause serious diseases.
  • The review specifically discusses Salmonella, Escherichia, Shigella, and Yersinia, detailing the diseases they cause and the impact on human health.
  • It emphasizes the importance of animal models in studying how these bacteria cause disease and identifying genetic factors that affect a person's susceptibility to infections.
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Background: Salmonella is a Gram-negative bacterium causing a wide range of clinical syndromes ranging from typhoid fever to diarrheic disease. Non-typhoidal Salmonella (NTS) serovars infect humans and animals, causing important health burden in the world. Susceptibility to salmonellosis varies between individuals under the control of host genes, as demonstrated by the identification of over 20 genetic loci in various mouse crosses.

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The Syst-OMICS consortium is sequencing 4,500 genomes and building an analysis pipeline for the study of genome evolution, antibiotic resistance and virulence genes. Metadata, including phenotypic as well as genomic data, for isolates of the collection are provided through the Foodborne Syst-OMICS database (SalFoS), at https://salfos.ibis.

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Biochar is a solid material obtained when biomass is thermochemically converted in an oxygen-limited environment. In most previous studies, the impacts of biochar on soil properties and organic carbon (C) were investigated under controlled conditions, mainly laboratory incubation or greenhouse studies. This 2-year field study was conducted to evaluate the influence of biochar on selected soil physical and chemical properties and carbon and nitrogen fractions for two selected soil types (clay loam and a sandy loam soil) under a corn (Zea mays L.

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Retention of iron in tissue macrophages upregulation of hepcidin (HAMP) and downregulation of the iron exporter ferroportin (FPN) is thought to participate in the establishment of anemia of inflammation after infection. However, an upregulation of FPN has been proposed to limit macrophages iron access to intracellular pathogens. Therefore, we studied the iron homeostasis and in particular the regulation of FPN after infection with serovar Typhimurium in mice presenting tissue macrophages with high iron (AcB61), basal iron (A/J and wild-type mice), or low iron ( knock out, ) levels.

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Human infection with Salmonella is of global public health concern. In low- and middle-income countries, Salmonella infection is a major source of disease in terms of both mortality and morbidity, while in high-income nations, the pathogen is an ongoing threat to food security. The outcome of infection with Salmonella enterica serovar Typhimurium (Salmonella Typhimurium) in mouse models is dependent upon a coordinated and complex immune response.

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Viral respiratory tract infections are the main causative agents of the onset of infection-induced asthma and asthma exacerbations that remain mechanistically unexplained. Here we found that deficiency in signaling via type I interferon receptor led to deregulated activation of group 2 innate lymphoid cells (ILC2 cells) and infection-associated type 2 immunopathology. Type I interferons directly and negatively regulated mouse and human ILC2 cells in a manner dependent on the transcriptional activator ISGF3 that led to altered cytokine production, cell proliferation and increased cell death.

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The outcome of infection with Salmonella Typhimurium in mouse models of human typhoid fever is dependent upon a coordinated complex immune response. A panel of recombinant congenic strains (RCS) derived from reciprocal backcross of A/J and C57BL/6J mice was screened for their susceptibility to Salmonella infection and two susceptibility loci, Ity4 (Immunity to Typhimurium locus 4) and Ity5, were identified. We validated Ity5 in a genetic environment free of the impact of Ity4 using a cross between A/J and 129S6.

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Coxsackievirus type B3 (CVB3) is a cardiotropic enterovirus. Infection causes cardiomyocyte necrosis and myocardial inflammation. The damaged tissue that results is replaced with fibrotic or calcified tissue, which can lead to permanently altered cardiac function.

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Microglia are tissue macrophages of the central nervous system (CNS) that control tissue homeostasis. Microglia dysregulation is thought to be causal for a group of neuropsychiatric, neurodegenerative and neuroinflammatory diseases, called "microgliopathies". However, how the intracellular stimulation machinery in microglia is controlled is poorly understood.

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