Publications by authors named "Hot D"

Insertion sequences (IS) represent mobile genetic elements that have been shown to be associated with bacterial evolution and adaptation due to their effects on genome plasticity. In , the causative agent of whooping cough, the numerous IS elements induce genomic rearrangements and contribute to the diversity of the global population. Previously, we have shown that the majority of IS-specific endogenous promoters induce the synthesis of alternative transcripts and thereby affect the transcriptional landscape of .

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Article Synopsis
  • Aging significantly impacts the severity and recovery from acute viral pneumonia, particularly in the context of COVID-19 as studied in hamsters.
  • Researchers utilized advanced metagenomics and metabolomics to explore the gut microbiota changes in young and aged hamsters, finding distinct age-related differences in gut health that correlate with disease outcomes.
  • The study highlights specific metabolites and bacterial changes linked to disease severity in older hamsters, suggesting that targeted microbiome interventions could improve management of pneumonia in elderly patients.
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Novel therapeutic strategies are urgently needed to combat pneumonia caused by strains resistant to standard-of-care antibiotics. Previous studies have shown that targeted stimulation of lung innate immune defenses through intranasal administration of the Toll-like receptor 5 agonist flagellin improves the treatment of pneumonia when combined with antibiotics. To promote translation to the clinic application, this study assessed the direct delivery of flagellin to the airways through nebulization using a vibrating mesh nebulizer in mice.

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Although the effects of cigarette smoke (CS) on the development of several intestinal diseases is well documented, the impact of e-cigarette aerosol (e-cig) on digestive health is largely unknown. To compare the effects of e-cig and CS on mouse ileum and colon, animals were chronically exposed for 6 months by nose-only inhalation to e-cig at 18 or 30 W power, or to 3R4F CS. Results showed that e-cig exposure decreased colon cell proliferation.

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The present work is aimed at studying how spatially periodic modulations of the refractive index of the medium, i.e., laser-induced gratings (LIGs), generated in a gas mixture containing methane (CH) by nanosecond pulses of resonant mid-infrared laser radiation, can be used to measure various gas parameters.

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Inspired by natural sideromycins, the conjugation of antibiotics to siderophores is an attractive strategy to facilitate "Trojan horse" delivery of antibiotics into bacteria. Genome analysis of a soil bacterium, found a "hybrid" biosynthetic gene cluster responsible for the production of both an antibiotic, pyridomycin, and a novel chlorocatechol-containing siderophore named chlorodactyloferrin. While both of these natural products were synthesized independently, analysis of the culture supernatant also identified a conjugate of both molecules.

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Background: The mycotoxin deoxynivalenol (DON) is a frequent contaminant of grain and cereal products worldwide. Exposure to DON can cause gastrointestinal inflammation, disturb gut barrier function, and induce gut dysbiosis in vivo under basal conditions, but little is known about the effects of DON ingestion in individuals with pre-existing gastrointestinal disease.

Objectives: Mice were orally exposed to 10 and 100 μg/kg bw/day of DON, corresponding to 10 to 100-fold human tolerable daily intake concentrations, and to the translation in mice of current human daily intake.

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Article Synopsis
  • * The HEV genome encodes three proteins, including ORF2, which has three isoforms with distinct roles in the virus's lifecycle, such as forming the viral capsid and acting as immune decoys.
  • * Research on ORF2 mutants revealed an Arginine-Rich Motif (ARM) that regulates ORF2's movement and functionality, helping the virus manipulate host cell processes for its survival and replication.
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Background And Aims: NOD2 has emerged as a critical player in the induction of both Th1 and Th2 responses for potentiation and polarisation of antigen-dependent immunity. Loss-of-function mutations in the NOD2-encoding gene and deregulation of its downstream signalling pathway have been linked to Crohn's disease. Although it is well documented that NOD2 is capable of sensing bacterial muramyl dipeptide, it remains counter-intuitive to link development of overt intestinal inflammation to a loss of bacterial-induced inflammatory response.

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Background: Emerging data indicate that prenatal exposure to air pollution may lead to higher susceptibility to several non-communicable diseases. Limited research has been conducted due to difficulties in modelling realistic air pollution exposure. In this study, pregnant mice were exposed from gestational day 10-17 to an atmosphere representative of a 2017 pollution event in Beijing, China.

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The ubiquitous and growing presence of microplastics (MPs) in all compartments of the environment raises concerns about their possible harmful effects on human health. Human exposure to MPs occurs largely through ingestion. Polyethylene (PE) is widely employed for reusable bags and food packaging and found to be present in drinking water and food.

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The development of nanotechnologies is leading to greater abundance of engineered nanoparticles (EN) in the environment, including in the atmospheric air. To date, it has been shown that the most prevalent EN found in the air are silver (Ag), titanium dioxide (TiO), titanium (Ti), and silicon dioxide (SiO). As the intestinal tract is increasingly recognized as a target for adverse effects induced by inhalation of air particles, the aim of this study was to assess the impact of these 4 atmospheric EN on intestinal inflammation and microbiota.

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spp. are enteric protozoa parasites that infect a variety of vertebrate hosts. These parasites are capable of inducing life-threatening gastrointestinal disease in immunocompromised individuals.

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The ability of bacterial pathogens to acquire essential micronutrients is critical for their survival in the host environment. Manganese plays a complex role in the virulence of a variety of pathogens due to its function as an antioxidant and enzymatic cofactor. Therefore, host cells deprive pathogens of manganese to prevent or attenuate infection.

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Rare actinomycetes are likely treasure troves for bioactive natural products, and it is therefore important that we enrich our understanding of biosynthetic potential of these relatively understudied bacteria. Dactylosporangium are a genus of such rare Actinobacteria that are known to produce a number of important antibacterial compounds, but for which there are still no fully assembled reference genomes, and where the extent of encoded biosynthetic capacity is not defined. Dactylosporangium vinaceum (NRRL B-16297) is known to readily produce a deep wine red-coloured diffusible pigment of unknown origin, and it was decided to define the chemical identity of this natural product pigment, and in parallel use whole genome sequencing and transcriptional analysis to lay a foundation for understanding the biosynthetic capacity of these bacteria.

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Laser-induced grating spectroscopy (LIGS) is for the first time explored in a configuration based on the crossing of two focused femtosecond (fs) laser pulses (800-nm wavelength) and a focused continuous-wave (cw) laser beam (532-nm wavelength). A thermal grating was formed by multi-photon absorption of the fs-laser pulses by [Formula: see text] with a pulse energy around 700 [Formula: see text]J ([Formula: see text] 45 TW/[Formula: see text]). The feasibility of this LIGS configuration was investigated for thermometry in heated nitrogen gas flows.

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Copper is both essential and toxic to living beings, which tightly controls its intracellular concentration. At the host-pathogen interface, copper is used by phagocytic cells to kill invading microorganisms. We investigated copper homeostasis in Bordetella pertussis, which lives in the human respiratory mucosa and has no environmental reservoir.

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It has previously been demonstrated that the ratio of the degenerate four wave mixing signal from two hot water line groups near 3231 cm can be used for seedless flame temperature measurements. This paper presents an investigation of the impact of saturation effects on the measured signal intensity from each line group, as well as an estimation of the accuracy of the method. The saturation effects observed here would result in a large systematic error if they are not taken into account when using the degenerate four-wave mixing intensity of these water line groups to calculate the flame temperature.

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Toxoplasmosis has been previously associated with an increased risk of having schizophrenia in several epidemiological studies. The aim of this prospective study was to examine for the first time a possible association between positive serology to Toxoplasma gondii (T. gondii) and schizophrenia in the Algerian population.

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regulates the production of its virulence factors by the two-component system BvgAS. In the virulence phase, BvgS phosphorylates BvgA, which then activates the transcription of virulence-activated genes (s). In the avirulence phase, such as during growth in the presence of MgSO, BvgA is not phosphorylated and the s are not expressed.

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Like all obligate intracellular pathogens, influenza A virus (IAV) reprograms host cell's glucose and lipid metabolism to promote its own replication. However, the impact of influenza infection on white adipose tissue (WAT), a key tissue in the control of systemic energy homeostasis, has not been yet characterized. Here, we show that influenza infection induces alterations in whole-body glucose metabolism that persist long after the virus has been cleared.

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Unhealthy lifestyle choices, such as bad eating behaviors and cigarette smoking, have major detrimental impacts on health. However, the inter-relations between obesity and smoking are still not fully understood. We thus developed an experimental model of high-fat diet-fed obese C57BL/6 male mice chronically exposed to cigarette smoke.

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Background: While respiratory viral infections are recognized as a frequent cause of illness in hematopoietic stem cell transplantation (HSCT) recipients, HCoV-OC43 infections have rarely been investigated as healthcare-associated infections in this population.

Objectives: In this report, HCoV-OC43 isolates collected from HSCT patients were retrospectively characterized to identify potential clusters of infection that may stand for a hospital transmission.

Study Design: Whole-genome and S gene sequences were obtained from nasal swabs using next-generation sequencing and phylogenetic trees were constructed.

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Abdominal aortic aneurysm (AAA) is a progressive vascular disease responsible for 1-4% of the deaths in elderly men. This study aimed to characterize specific microRNA (miRNA) expression in aneurysmal smooth muscle cells (SMCs) and macrophages in order to identify circulating miRNAs associated with AAA. We screened 850 miRNAs in aneurysmal SMCs, M1 and M2 macrophages, and in control SMCs isolated by micro-dissection from aortic biopsies using microarray analysis.

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