Search results for "infectious"
showing 10 items of 2953 documents
Immunization against Hepatitis B Surface Antigen (HBsAg) in a Cohort of Nursing Students Two Decades after Vaccination: Surprising Feedback
2019
Health-care students can be exposed to biological risks during university training. The persistence of long-term immunogenicity against hepatitis B virus (HBV) was analyzed in a cohort of nursing students two decades after primary vaccination. A total of 520 students were enrolled at the University of Palermo and were evaluated for levels of anti-HBsAg antibodies. The students were examined during the first year of their Degree Course and were checked two years later. All students with anti-HBsAg <
Disentangling the effect of host genetics and gut microbiota on resistance to an intestinal parasite
2019
11 pages; International audience; Resistance to infection is a multifactorial trait, and recent work has suggested that the gut microbiota can also contribute to resistance. Here, we performed a fecal microbiota transplant to disentangle the contribution of the gut microbiota and host genetics as drivers of resistance to the intestinal nematode Heligmosomoides polygyrus. We transplanted the microbiota of a strain of mice (SJL), resistant to H. polygyrus, into a susceptible strain (CBA) and vice-versa. We predicted that if the microbiota shapes resistance to H. polygyrus, the FMT should reverse the pattern of resistance between the two host strains. The two host strains had different microbi…
Gut-microbiota-derived extracellular vesicles: Overlooked mediators in host–helminth interactions?
2021
Helminth infections impact the composition of the mammalian gut microbiota; however, the mechanisms underpinning these interactions are, thus far, unknown. In this article, we propose that microbiota-derived extracellular vesicles might represent key players in host-helminth-microbiome crosstalk, and outline future directions to elucidate their role(s) in host-parasite relationships.
Th2 and Th1 Responses: Clear and Hidden Sides of Immunity Against Intestinal Helminths.
2017
Intestinal helminthiases affect millions of people worldwide, mainly in developing regions, where they cause a significant negative impact on human health and socioeconomic growth of affected populations. However, intestinal helminthiases are still among the most neglected tropical diseases. Protective immunity against intestinal helminths is associated with development of type 2 responses. Nevertheless, in some host–intestinal helminth combinations, local Th1 responses are initiated, inducing chronicity. The usage of helminth–mouse models is useful for elucidating the mechanisms behind the initiation of each type of response. Herein, the current knowledge on these topics is reviewed, payin…
Classic Models for New Perspectives: Delving into Helminth–Microbiota–Immune System Interactions
2018
Whilst a wealth of data indicate that infections by gastrointestinal helminths are accompanied by significant alterations in the composition of the vertebrate gut flora, little is known of the immune-molecular mechanisms that regulate host-parasite-microbiota interactions. 'Traditional' experimental models of gastrointestinal helminthiases, in which the role(s) of each of the components of this triad can be tested, provide an opportunity to advance research in this area. In this article, we propose the Echinostoma caproni-mouse system as a potentially useful tool for studies of the role of the host gut microbiota in preventing pathology and inducing parasite clearance via interleukin (IL)-2…
Genetic characterization of influenza viruses from influenza-related hospital admissions in the St. Petersburg and Valencia sites of the Global Influ…
2016
Abstract Background Continuous surveillance for genetic changes in circulating influenza viruses is needed to guide influenza prevention and control. Objectives To compare intra-seasonal influenza genetic diversity of hemagglutinin in influenza A strains isolated from influenza hospital admissions collected at two distinct sites during the same season. Study design Comparative phylogenetic analysis of full-length hemagglutinin genes from 77 isolated influenza A viruses from the St. Petersburg, Russian Federation and Valencia, Spain sites of the Global Influenza Hospital Surveillance Network (GIHSN) during the 2013/14 season. Results We found significant variability in A(H3N2) and A(H1N1)pdm…
Rab33B Controls Hepatitis B Virus Assembly by Regulating Core Membrane Association and Nucleocapsid Processing
2017
Many viruses take advantage of cellular trafficking machineries to assemble and release new infectious particles. Using RNA interference (RNAi), we demonstrate that the Golgi/autophagosome-associated Rab33B is required for hepatitis B virus (HBV) propagation in hepatoma cell lines. While Rab33B is dispensable for the secretion of HBV subviral envelope particles, its knockdown reduced the virus yield to 20% and inhibited nucleocapsid (NC) formation and/or NC trafficking. The overexpression of a GDP-restricted Rab33B mutant phenocopied the effect of deficit Rab33B, indicating that Rab33B-specific effector proteins may be involved. Moreover, we found that HBV replication enhanced Rab33B expres…
DNA multigene characterization of Fasciola hepatica and Lymnaea neotropica and its fascioliasis transmission capacity in Uruguay, with historical cor…
2017
Background Fascioliasis is a pathogenic disease transmitted by lymnaeid snails and recently emerging in humans, in part due to effects of climate changes, anthropogenic environment modifications, import/export and movements of livestock. South America is the continent presenting more human fascioliasis hyperendemic areas and the highest prevalences and intensities known. These scenarios appear mainly linked to altitude areas in Andean countries, whereas lowland areas of non-Andean countries, such as Uruguay, only show sporadic human cases or outbreaks. A study including DNA marker sequencing of fasciolids and lymnaeids, an experimental study of the life cycle in Uruguay, and a review of hum…
Highlights of the São Paulo ISEV workshop on extracellular vesicles in cross-kingdom communication
2017
In the past years, extracellular vesicles (EVs) have become an important field of research since EVs have been found to play a central role in biological processes. In pathogens, EVs are involved in several events during the host–pathogen interaction, including invasion, immunomodulation, and pathology as well as parasite–parasite communication. In this report, we summarised the role of EVs in infections caused by viruses, bacteria, fungi, protozoa, and helminths based on the talks and discussions carried out during the International Society for Extracellular Vesicles (ISEV) workshop held in São Paulo (November, 2016), Brazil, entitled Cross-organism Communication by Extracellular Vesicles:…
Phage Biodiversity in Artisanal Cheese Wheys Reflects the Complexity of the Fermentation Process
2017
Dairy fermentations constitute a perfect âbreeding groundâ for bacteriophages infecting starter cultures, particularly strains of Lactococcus lactis. In modern fermentations, these phages typically belong to one of three groups, i.e., the 936, P335, and c2 phage groups. Traditional production methods present fewer chemical and physical barriers to phage proliferation compared to modern production systems, while the starter cultures used are typically complex, variable, and undefined. In the current study, a variety of cheese whey, animal-derived rennet, and vat swab samples from artisanal cheeses produced in Sicily were analysed for the presence of lactococcal phages to assess phage div…