Search results for "INFECTIONS"
showing 10 items of 2671 documents
Antiidiotypic DNA vaccination induces serum bactericidal activity and protection against group B meningococci
2006
No vaccine is available for preventing infections by serogroup B Neisseria meningitidis (MenB), which accounts for a major portion of meningococcal cases in developed countries, because of the poor immunogenicity of the capsular polysaccharide (CP) even after protein conjugation. We have previously induced anticapsular antibodies by immunization with a single chain variable fragment (scFv), which mimics a protective CP epitope. This surrogate antigen, however, was ineffective at inducing serum bactericidal activity, an accepted marker of protection in humans. Serum bactericidal activity was consistently achieved by immunizing mice with the scFv-encoding gene. Immunization with vectors witho…
Role of iron, capsule, and toxins in the pathogenicity of Vibrio vulnificus biotype 2 for mice
1994
The virulence mechanisms of Vibrio vulnificus biotype 2 have been studied and compared with those of biotype 1 in mice as the experimental animals. Biotype 2 isolates from European eels were as virulent for mice as biotype 1 strains (50% lethal dose, about 10(5) CFU per mouse); a septicemic infection developed in less than 24 h. These strains had several properties in common with biotype 1 organisms including capsule expression, uptake of various iron sources, and production of exoproteins, whose role in mouse virulence has been demonstrated. We also discuss the implication of biotype 2 strains in human infections.
The role of morbid obesity in the promotion of metabolic disruptions and non-alcoholic steatohepatitis by Helicobacter Pylori
2016
Background Helicobacter pylory (HP) infection has been associated to an increased rate of type 2 diabetes (T2D) and liver disease through its effect on insulin resistance and systemic inflammation. However, results are inconstant and no studies exist in morbidly obese patients, in which both insulin resistance and inflammation coexist. Material and methods Cross-sectional study to evaluate the relationship between HP infection and alterations in carbohydrate metabolism, lipid profile, inflammation markers, and liver disease in patients awaiting for bariatric surgery. HP infection was histologically assessed in gastric antrum biopsy from 416 subjects. Liver biopsy was also available in 93 su…
Acute Laryngitis in the Rat Induced by Moraxella catarrhalis and Bordetella pertussis: Number of Neutrophils, Dendritic Cells, and T and B Lymphocyte…
1999
Infectious laryngotracheitis results in fulminant respiratory distress. During the disease, the subglottic mucosa is selectively infected and swollen, the reason for this preference being unknown. Therefore, in the present study the immunoreaction of the laryngeal mucosa was studied in the rat after inhalation of either heat-killed Moraxella catarrhalis (PVG rats) or application of viable Bordetella pertussis (BN rats). The number of neutrophils, macrophages, dendritic cells, and T and B lymphocytes was determined in the mucosa of the supraglottic, glottic, and subglottic area of the larynx as well as in the trachea. After application of the pathogens, the mucosa of the subglottic area was …
Holistic and unified approach to facilitate graphical data visualization and statistical predictive modelling for diseases at the microorganism level
2015
Borrelia species are predominantly responsible for the most common form of Tick-borne diseases (TBD) which is Lyme borreliosis (LB). Episodes of Lyme arthritis (LA) is a hallmark symptom of LB patients. LA is an atypical form of reactive arthritis (ReA) that is a sub-type of Spondyloarthritis (SpA). Coinfections such as Ehrlichia chaffeensis accompany primary Borrelia species during the later stages of LB infection to induce severe symptoms. Currently, there is no holistic approach that would unify different TBD pathogens into independent and multiple TBD infection (MTBDI) combination categories to facilitate graphical and statistical analysis between any two patients groups. The chronic ma…
Brightness and contrast do not affect visually induced motion sickness in a passively-flown fixed-base flight simulator
2016
Abstract Background Visually Induced Motion Sickness (VIMS) or simulator sickness is often elicited by a visual stimulus that lacks the appropriate vestibular or proprioceptive feedback. In this study, we chose to investigate the effects of brightness and contrast of the visual scene on VIMS. Hypothesis We hypothesized that visual environments differing in brightness or contrast would differentially induce VIMS. The symptoms of VIMS should be most severe for the combination of high brightness and high contrast and conversely lowest for the low brightness and low contrast condition. Methods 33 healthy subjects were tested in a fixed-base flight simulator. Each subject flew in four consecutiv…
Reduced T-cell receptor CD3ζ-chain protein and sustained CD3ε expression at the site of mycobacterial infection
2001
Control of mycobacterial infection by the cellular immune system relies both on antigen-presenting cells and on T lymphocytes. The quality of an effective cellular immune response is dependent on functional signal transduction residing in the cytoplasmic tails of the T-cell receptor CD3 components. In order to investigate potential effects of mycobacteria on T-cell receptor signalling, we examined the protein expression of T-cell signal transduction molecules (CD3zeta, ZAP-70, p59fyn, p56lck). In Western blots of peripheral blood mononuclear cells of Mycobacterium tuberculosis infected patients, only the CD3zeta-chain showed a marked reduction in protein expression. To investigate the situa…
Timing of activation of CD4+ memory cells as a possible marker to establish the efficacy of vaccines against contagious agalactia in sheep
2013
Mycoplasma agalactiae is a major pathogen of sheep and goats in many areas of the world and particularly in Mediterranean countries. It causes contagious agalactia, an infectious disease primarily affecting mammary glands. Many vaccines against the pathogen are currently under development. The aim of the study was to investigate the involvement of T cell-mediated immunity during vaccination and challenge experiments against Mycoplasma agalactiae. A comparison of the antigen-specific expansion of interferon gamma positive T cell memory and naïve subsets was performed between vaccinated and non-vaccinated sheep to identify cellular subsets whose activation was different between protected and …
Reconstitution of CD8 T cells is essential for the prevention of multiple-organ cytomegalovirus histopathology after bone marrow transplantation.
1998
Cytomegalovirus (CMV) infection in the period of temporary immunodeficiency after haematoablative treatment and bone marrow transplantation (BMT) is associated with a risk of graft failure and multiple-organ CMV disease. The efficacy of immune system reconstitution is decisive for the prevention of CMV pathogenesis after BMT. Previous data in murine model systems have documented a redundancy in the immune effector mechanisms controlling CMV. CD8 T cells proved to be relevant but not irreplaceable as antiviral effectors. Specifically, in a state of long-term in vivo depletion of the CD8 T-cell subset, CD4 T cells were educed to become deputy effectors controlling CMV by a mechanism involving…
Oral delivery of homologous and heterologous strains of rotavirus to BALB/c mice induces the same profile of cytokine production by spleen cells.
1998
Abstract In this work, we wanted to clarify if differences in antibody (Ab) and particularly in secretory immunoglobulin A (IgA) responses following homologous or heterologous rotavirus infection could be explained by different priming of specific T helper (Th) cells. We compared the Ab responses from suckling BALB/c mice orally inoculated with either a heterologous simian (SA11) or bovine (RF) rotavirus or a homologous murine rotavirus (EHP w ), as well as the profile of cytokines produced by spleen cells after in vitro restimulation. Oral inoculation of EHP w and SA11 induced a similar pattern of Ab with mucosal and serum IgA associated with serum IgG with equal levels of IgG1 and IgG2a, …