Search results for "pathogen"
showing 10 items of 1657 documents
Intra-specific variability and biological relevance of P3N-PIPO protein length in potyviruses
2013
Background:Pipo was recently described as a new ORF encoded within the genome of the Potyviridae family members (PNAS 105:5897-5902, 2008). It is embedded within the P3 cistron and is translated in the +2 reading frame relative to the potyviral long ORF as the P3N-PIPO fusion protein. In this work, we first collected pipo nucleotide sequences available for different isolates of 48 Potyvirus species. Second, to determine the biological implications of variation in pipo length, we measured infectivity, viral accumulation, cell-to-cell and systemic movements for two Turnip mosaic virus (TuMV) variants with pipo alleles of different length in three different susceptible host species, and tested…
Granulozytenfunktion bei Frühgeborenen ab der 34. Schwangerschaftswoche und bei reifen Neugeborenen
1999
BACKGROUND Preterm and term neonates have an increased risk to develop severe bacterial infections. Impairment of neutrophil function may be responsible for this increased risk. Other diseases related to prematurity like retinopathia of prematurity (ROP) or broncho-pulmonary dysplasia (BPD) on the other hand may be due to poorly controlled O2-radical production. PATIENTS AND METHODS Blood samples of 112 premature (34 weeks of gestation and older) and term neonates were analysed. Blood samples of 23 healthy adults (18 to 50 years old) served as controls. O2-radical production and phagocytosis of neutrophils were determined by flow cytometry, using a commercial test system. RESULTS Under the …
Oxidative stress and mitochondrial dysfunction in Kindler syndrome
2014
This is an Open Access article distributed under the terms of the Creative Commons Attribution License.-- et al.
Cellular Models and Assays to Study NLRP3 Inflammasome Biology
2020
The NLRP3 inflammasome is a multi-protein complex that initiates innate immunity responses when exposed to a wide range of stimuli, including pathogen-associated molecular patterns (PAMPs) and danger-associated molecular patterns (DAMPs). Inflammasome activation leads to the release of the pro-inflammatory cytokines interleukin (IL)-1β and IL-18 and to pyroptotic cell death. Over-activation of NLRP3 inflammasome has been associated with several chronic inflammatory diseases. A deep knowledge of NLRP3 inflammasome biology is required to better exploit its potential as therapeutic target and for the development of new selective drugs. To this purpose, in the past few years, several tools have…
Caspase-dependent apoptosis during infection with Cryptosporidium parvum
1999
The protozoan parasite Cryptosporidium parvum causes persistent diarrhea and malnutrition in children and the diarrhea-wasting syndrome in AIDS. No therapy exists for eliminating the parasite in the absence of a healthy immune response. Although it had been reported that infection of intestinal cell lines with C. parvum leads to host cell death, the mechanisms of cytolysis have not been characterized. We show here that infection with C. parvum leads to typical apoptotic nuclear condensation and DNA fragmentation in host cells. Both nuclear condensation and DNA fragmentation are inhibited by a caspase inhibitor, showing that caspases are involved in this type of apoptosis. Finally, blocking …
Human parvovirus B19 induced apoptotic bodies contain altered self-antigens that are phagocytosed by antigen presenting cells.
2013
Human parvovirus B19 (B19V) from the erythrovirus genus is known to be a pathogenic virus in humans. Prevalence of B19V infection has been reported worldwide in all seasons, with a high incidence in the spring. B19V is responsible for erythema infectiosum (fifth disease) commonly seen in children. Its other clinical presentations include arthralgia, arthritis, transient aplastic crisis, chronic anemia, congenital anemia, and hydrops fetalis. In addition, B19V infection has been reported to trigger autoimmune diseases such as systemic lupus erythematosus and rheumatoid arthritis. However, the mechanisms of B19V participation in autoimmunity are not fully understood. B19V induced chronic dise…
T cell-independent joint destruction
1998
Rheumatoid Arthritis (RA) is a chronic systemic disorder of unknown etiology. Although, early and late stages of the disease may be driven by different processes, affected joints are characterized by inflammation, synovial hyperplasia, and abnormal immune responses [1]. The abundance of T cells within the rheumatoid synovium as well as the association of certain major histocompatibility complex (MHC) class II molecules with RA [2] implied a central role for T cells in the pathophysiology of the disease. However, recent advances in molecular biology have fostered new concepts for the pathogenesis of RA. Specifically, the investigation of early stages of disease, the development of novel anim…
Dominant role of paraoxonases in inactivation of the Pseudomonas aeruginosa quorum-sensing signal N-(3-oxododecanoyl)-L-homoserine lactone.
2008
Pseudomonas aeruginosa is an opportunistic bacterium which causes serious infections in immunocompromised and cystic fibrosis patients (10). As with many gram-negative bacteria, P. aeruginosa produces acyl-homoserine lactone (AHL) quorum-sensing (QS) signaling molecules termed autoinducers which allow the single-celled organisms to coordinate their actions (36). N-(3-Oxododecanoyl)-l-homoserine lactone (3OC12-HSL) is a key autoinducer synthesized by P. aeruginosa which regulates the expression of extracellular virulence factors and biofilm formation (5, 36). Rats and mice experimentally infected with P. aeruginosa mutants deficient in the ability to produce or respond to 3OC12-HSL exhibited…
Microbiological control of soil-borne phytopathogenic fungi with special emphasis on wilt-inducing Fusarium oxysporum
2009
Contents Summary 529 I. Biological control of plant diseases: state of the art 530 II. Main modes of action of biological control agents 530 III. The protective strains of F. oxysporum: an unexplored model 532 IV. Future directions for the study of the protective capacity of strains of F. oxysporum 539 V. How to make biological control successful in the field? 540 References 541 Summary Plant diseases induced by soil-borne plant pathogens are among the most difficult to control. In the absence of effective chemical control methods, there is renewed interest in biological control based on application of populations of antagonistic micro-organisms. In addition to Pseudomonas spp. a…
Cell Susceptibility to Baculovirus Transduction and Echovirus Infection Is Modified by Protein Kinase C Phosphorylation and Vimentin Organization
2013
ABSTRACT Some cell types are more susceptible to viral gene transfer or virus infection than others, irrespective of the number of viral receptors or virus binding efficacy on their surfaces. In order to characterize the cell-line-specific features contributing to efficient virus entry, we studied two cell lines (Ea.hy926 and MG-63) that are nearly nonpermissive to insect-specific baculovirus (BV) and the human enterovirus echovirus 1 (EV1) and compared their characteristics with those of a highly permissive (HepG2) cell line. All the cell lines contained high levels of viral receptors on their surfaces, and virus binding was shown to be efficient. However, in nonpermissive cells, BV and it…