Publications by authors named "Fontaine T"

The cell wall of human fungal pathogens plays critical roles as an architectural scaffold and as a target and modulator of the host immune response. Although the cell wall of the pathogenic yeast is intensively studied, one of the major fibrillar components in its cell wall, β-1,6-glucan, has been largely neglected. Here, we show that β-1,6-glucan is essential for bilayered cell wall organization, cell wall integrity, and filamentous growth.

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  • The melanocortin receptor 4 (MC4R) is a crucial component in regulating hunger and fullness through its interaction with hormones like α-melanocyte-stimulating hormone and agouti-related peptide.
  • Researchers developed a unique hybrid structure using a ConfoBody that helps them discover a variety of MC4R-specific, potent nanobodies that act as full agonists.
  • The study revealed the structure of MC4R with a full agonistic nanobody at a high resolution, showing that this specific nanobody could potentially be more effective and targeted for anti-obesity treatments compared to existing peptide agonists.
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Legionella longbeachae and Legionella pneumophila are the most common causative agents of Legionnaires' disease. While the clinical manifestations caused by both species are similar, species-specific differences exist in environmental niches, disease epidemiology, and genomic content. One such difference is the presence of a genomic locus predicted to encode a capsule.

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Squamous cell carcinoma (SCC) is the most common malignant tumor involving the temporal bone but generally very rare. The temporomandibular joint (TMJ), middle cranial fossa, and facial nerve canal are uncommon areas for the tumor to spread. We present the case of primary SCC of the temporal bone in a 63-year-old male presenting for otorrhea, otalgia, facial weakness, and facial pain after failing outpatient antibiotic therapy for an ear infection.

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Progressive multifocal leukoencephalopathy (PML) is a rare demyelinating disease of the central nervous system (CNS) due to John Cunningham (JC) virus reactivation most often in immunocompromised patients. The brainstem and the anterior corpus callosum are uncommon locations for white matter lesions. We present a case of PML in a 40-year-old female presenting to the emergency department for a tonic seizure with transient postictal confusion.

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  • PTX3 is a protective molecule that interacts with the fungus Aspergillus fumigatus in different ways, depending on the fungal form (germinating vs. dormant conidia).
  • It recognizes germinating conidia through a specific polysaccharide and interacts with dormant conidia through weak binding with surface proteins, while other proteins (SP-D, C1q, C3b) enhance this interaction.
  • PTX3 helps regulate inflammation by reducing the production of pro-inflammatory signals and increasing anti-inflammatory signals like IL-10 in immune responses related to aspergillosis and potentially serves as a biomarker for certain fungal infections.
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Antifungal echinocandins inhibit the biosynthesis of β-1,3-glucan, a major and essential polysaccharide component of the fungal cell wall. However, the efficacy of echinocandins against the pathogen Aspergillus fumigatus is limited. Here, we use solid-state nuclear magnetic resonance (ssNMR) and other techniques to show that echinocandins induce dynamic changes in the assembly of mobile and rigid polymers within the A.

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A meningioma is a rare primary CNS tumor that tends to present more so in females in a slowly progressive fashion. The cavernous sinus and cerebellopontine angle are uncommon locations for meningiomas. We present a case of a meningioma in a 60-year-old female presenting to the emergency department for a sudden onset headache, vertigo, facial paresthesias, and chest pain.

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Invasive aspergillosis causes significant morbidity and mortality in immunocompromised patients. Natural killer (NK) cells are pivotal for antifungal defense. Thus far, CD56 is the only known pathogen recognition receptor on NK cells triggering potent antifungal activity against Aspergillus fumigatus.

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Lacticaseibacillus rhamnosus Lcr35 is a well-known bacterial strain whose efficiency in preventing recurrent vulvovaginal candidiasis has been largely demonstrated in clinical trials. The presence of sodium thiosulfate (STS) has been shown to enhance its ability to inhibit the growth of Candida albicans strains. In this study, we confirmed that Lcr35 has a fungicidal effect not only on the planktonic form of C.

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Introduction: A positive experience in mammography is essential for increasing patient attendance and reattendance at these examinations, whether conducted for diagnostic or screening purposes. Mammograms indeed facilitate early disease detection, enhance the potential for cure, and consequently reduce breast cancer mortality. The main objective of this review was to identify and map the strategies aiming to improve the patient experience in diagnostic and screening mammography.

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  • Bacterial biofilms are tough clusters of bacteria that resist antibiotics, prompting the exploration of non-toxic compounds to stop their formation.
  • Researchers identified seven new polysaccharides that can prevent biofilm formation in E. coli and Staphylococcus aureus without killing the bacteria.
  • The study reveals that active polysaccharides exhibit unique electrokinetic properties, which could help in discovering or designing effective non-biocidal compounds for controlling biofilms in various applications.
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  • * There is a growing concern about the emergence of resistance to first-line antifungals, particularly azoles, which complicates treatment options and results in even higher mortality rates for resistant infections.
  • * Some A. fumigatus isolates show persistence to voriconazole, allowing them to survive and grow even in the presence of high drug levels; this persistence appears to be an active response and could be a significant factor in treatment failure for patients with aspergillosis.
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GPI-anchored proteins display very diverse biological (biochemical and immunological) functions. An in silico analysis has revealed that the genome of contains 86 genes coding for putative GPI-anchored proteins (GPI-APs). Past research has demonstrated the involvement of GPI-APs in cell wall remodeling, virulence, and adhesion.

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Earlier studies have shown that the outer layers of the conidial and mycelial cell walls of are different. In this work, we analyzed the polysaccharidome of the resting conidial cell wall and observed major differences within the mycelium cell wall. Mainly, the conidia cell wall was characterized by (i) a smaller amount of α-(1,3)-glucan and chitin; (ii) a larger amount of β-(1,3)-glucan, which was divided into alkali-insoluble and water-soluble fractions, and (iii) the existence of a specific mannan with side chains containing galactopyranose, glucose, and N-acetylglucosamine residues.

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Aspergillus fumigatus is a ubiquitous environmental mold that causes significant mortality particularly among immunocompromised patients. The detection of the -derived carbohydrate galactomannan in patient serum and bronchoalveolar lavage fluid is the major biomarker used to detect A. fumigatus infection in clinical medicine.

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Objective: The objective of this review is to map the global evidence on interventions aiming to enhance the patient experience during mammography examination.

Introduction: Mammography is the examination of choice to detect breast cancer, which is the most common malignant condition among women globally. However, this examination can cause psychological distress, discomfort, and pain for patients.

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Objective: The aim of this project was to develop and align an inpatient psychiatric safety event taxonomy that would blend well-established safety events with psychiatry-specific concerns.

Methods: A hybrid inductive-deductive thematic analysis was used to generate novel descriptive safety event categories for inpatient psychiatry and align these categories with an established taxonomic framework. In the inductive phase, an initial taxonomy was developed by describing the semantic subject and context of reported safety concerns.

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Humoral immunity plays a defensive role against invading microbes. However, it has been largely overlooked with respect to , an airborne fungal pathogen. Previously, we have demonstrated that surfactant protein D (SP-D), a major humoral component in human lung-alveoli, recognizes conidial surface exposed melanin pigment.

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Invasive fungal infections remain highly problematic for human health. Collectively, they account for more than 1 million deaths a year in addition to more than 100 million mucosal infections and 1 billion skin infections. To be able to make progress it is important to understand the pathobiology of fungal interactions with the immune system.

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Vast efforts have been devoted to the development of antifungal drugs targeting the cell wall, but the supramolecular architecture of this carbohydrate-rich composite remains insufficiently understood. Here we compare the cell wall structure of a fungal pathogen Aspergillus fumigatus and four mutants depleted of major structural polysaccharides. High-resolution solid-state NMR spectroscopy of intact cells reveals a rigid core formed by chitin, β-1,3-glucan, and α-1,3-glucan, with galactosaminogalactan and galactomannan present in the mobile phase.

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Natural products play a vital role for intermicrobial interactions. In the basidiomycete arena an important representative is variegatic acid, a lactone natural product pigment whose ecological relevance stems from both inhibiting bacterial swarming and from indirect participation in breakdown of organic matter by brown-rotting fungi. Previous work showed that the presence of bacteria stimulates variegatic acid production.

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  • Researchers investigated how the compound Congo red (CR) inhibits fungal growth by binding to β-1,3-glucans, ultimately disrupting cell wall synthesis.
  • A study of a mutant library revealed CR-resistant and hypersensitive mutants, with some mutants showing larger, abnormal cells called Quasimodo cells that could absorb more CR.
  • Long-term CR exposure led to a novel phenomenon termed drug-induced growth stimulation (DIGS), where some fungi showed renewed growth after recovering from CR stress, highlighting the complexity of fungal responses to CR.
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