Interaction of pneumococcal phase variation, host and pressure/gas composition: virulence expression of NanA, HylA, PspA and CbpA in simulated otitis media.

Streptococcus pneumoniae, a leading cause of otitis media (OM), adapts to the host environment and undergoes spontaneous intra-strain phase variations in colony morphology. Transparent (T) phase variants are more efficient in colonizing the nasopharynx while the opaque (O) phase variants exhibit greater virulence during systemic infections. We recently demonstrated that T phase variants exhibited a higher growth rate and greater epithelial adherence and destruction than did O phase variants during interactions with human middle ear (ME) epithelial cells.

Nasal secretion concentrations of IL-5, IL-6, and IL-10 in children with and without upper respiratory tract viruses.

Objective: To determine if levels of interleukin (IL) 5, IL-6, and IL-10 or their ratios in nasal secretion are diagnostic of viral upper respiratory tract infections (vURTIs) and coldlike illnesses (CLIs) in children.

Design: Longitudinal study of children for vURTIs, CLIs, and concentrations and ratios of nasal cytokines.

Setting: Outpatient assessments of children.

The interleukin 6 -174 C/C genotype predicts greater rhinovirus illness.

Background: In adults and children with respiratory syncytial virus (RSV) infection, a polymorphism in the interleukin 6 (IL-6) promoter at position -174 predicts illness magnitude. In addition, polymorphisms in the interleukin 10 (IL-10), tumor necrosis factor alpha (TNF-alpha), and interferon gamma (IFN-gamma) genes are associated with immune responsiveness and the frequency of complications. Here, the effect of these polymorphisms on illness and seroconversion during infection with rhinovirus type 39 (RV39) was evaluated.

Interaction of phase variation, host and pressure/gas composition: pneumococcal gene expression of PsaA, SpxB, Ply and LytA in simulated middle ear environments.

Objective: Streptococcus pneumoniae, a leading cause of otitis media (OM), undergoes spontaneous intra-strain variations in colony morphology. Transparent (T) variants are more efficient in colonizing the nasopharynx while opaque (O) variants exhibit greater virulence during systemic infections. This study was intended to delineate the underlying molecular mechanisms by which the predominant S.

Interaction of pneumococcal phase variation and middle ear pressure/gas composition: an in vitro model of simulated otitis media.

Streptococcus pneumoniae, a leading cause of otitis media (OM), undergoes spontaneous intra-strain variations in colony morphology. Transparent (T) variant is more efficient in colonizing the nasopharynx while the opaque (O) variant exhibits greater virulence during systemic infections. We hypothesized that changes in middle ear (ME) gas pressure/composition during Eustachian tube (ET) dysfunction and the treatment of that dysfunction, e.

Age-dependent differential expression of fibronectin variants in skin and airway mucosal wounds.

Objective: To delineate age-dependent and tissue-specific molecular activities of the variant-inclusion fibronectin transcripts in fetal and postnatal skin and airway mucosal wounds during early events of the wound healing process. Fibronectin is involved in multiple steps of the wound healing process. The functional complexity of fibronectin is carried through its protein diversity, which is controlled in part by alternative RNA splicing, a coordinated transcription and RNA processing.

Identification of a pre-mRNA splicing factor, arginine/serine-rich 3 (Sfrs3), and its co-expression with fibronectin in fetal and postnatal rabbit airway mucosal and skin wounds.

Fibronectin (FN) is a multi-functional, adhesion protein and involved in multi-steps of the wound healing process. Strong evidence suggests that FN protein diversity is controlled by alternative RNA splicing; a coordinated transcription and RNA processing that is development-, age-, and tissue/cell type-regulated. We previously demonstrated that fetal rabbit airway mucosal healing is regenerative and scarless.

Mucosal expression of genes encoding possible upstream regulators of Na+ transport during pneumococcal otitis media.

Objective: Recently, we reported that gene transcripts encoding 3 Na+ transport proteins (pump, channel and exchanger) in the middle ear mucosa (MEM) were simultaneously suppressed at 12 and 48 h after Streptococcus pneumoniae (SP) challenge of rat middle ears.

Material And Methods: From cDNA microarray screening of those specimens, several gene clusters, including Nos2 and the transcription factors Fos, Fosl1, Jun and Nfkb1, were identified as possible upstream regulators of Na+ transport protein expression. The altered expression of those genes in MEM was validated and quantified using real-time polymerase chain reaction and MEM protein expression for Atp1a1, Nos2 and Nfkb1 was studied using Western blot and/or immunohistochemistry assays.

The effect of changes in ambient oxygen concentration on the bioelectric properties of middle ear mucosa.

The purpose of the present study was to compare the effect of 24 h of exposure to 7% O2 (normal middle ear physiological conditions) vs. 21% O2 (found in the middle ear after ventilation tube placement) on transepithelial Na+ absorption and Cl- secretion in cultured gerbil middle ear epithelial cell monolayers. Although no difference in apical Na+ absorption was identified, the UTP-induced stimulation of apical Cl- secretion in the presence of apical Na+ channel blockade with amiloride was significantly enhanced after exposure to 21% O2 compared with 7% O2 exposure.