Citations

PurposePrevious research suggests that school-age children with minimal hearing loss (CMHL) are at risk for a variety of psychoeducational problems. However, CMHL are a heterogeneous group, and the profile of at-risk children is unknown. Data regarding the characteristics of early school-age CMHL are needed to extend previous findings and determine potential risk factors associated with psychoeducational difficulties.MethodPsychoeducational outcomes were evaluated at baseline and longitudinally in age-matched groups of 27 CMHL (ages 4–10 years) and 26 children with normal hearing (CNH) using assessments of language, reading, behavior, speech recognition in noise, and cognition. Additional analyses were used to identify demographic characteristics among CMHL that are associated with psychoeducational difficulties.ResultsAt the earliest age tested, CMHL had greater teacher-rated attention difficulties in the classroom than CNH. Differences in the rate of psychoeducational development were not observed between groups. Among CMHL, psychoeducational difficulties were associated with delays in identification of hearing loss and low maternal education.ConclusionsClassroom attention abilities should be monitored for early school-age CMHL. Late-identified CMHL and CMHL with low maternal education levels may be in particular need of academic and social support. Continued efforts for early identification of CMHL should be made to improve outcomes for these children.

Purpose In this study, the authors examined mean volumes of discrete sips performed by healthy adults from straws varying in internal diameter. Method Forty healthy adults sipped water from each of 7 straws varying in internal diameter (0.65–5.00 mm). Bolus volumes associated with 3 discrete sips were recorded under each sip condition. Results Straw diameter had a significant effect on bolus size, with the smallest diameter straws eliciting the smallest bolus volumes. Bolus volumes did not vary according to age or sex. Considerable intersubject variation was observed, particularly for the straws with the largest diameters. Intrasubject variability across 3 trials was minimal. Conclusions The findings support the hypothesis that narrower straw diameters are associated with smaller bolus volumes in healthy adults. Additional study is needed to determine whether individuals with dysphagia demonstrate similar patterns of bolus size associated with straws varying in internal diameter and whether such variations have clinical benefit.

Objective To compare the suitability of CO2 laser with steel instruments for margin excision in transoral laser microsurgery. Methods Prospective randomized blinded study. Patients with glottic cancer undergoing laser resection were randomized to margin excision by either steel instruments or CO2 laser. Margins were analyzed for size, interpretability and degree of artifact by a pathologist who was blinded to technique. Results 45 patients were enrolled in the study with 226 total margins taken. 39 margins taken by laser had marked artifact and 0 were uninterpretable. 20 margins taken by steel instruments had marked artifact, and 2 were uninterpretable. Controlling for margin size, the laser technique was associated with increasing degrees of margin artifact (p = 0.210), but there was no difference in crude rates of uninterpretability (p = 0.24). Conclusion Laser margin excision is associated with a greater degree of artifact than steel instrument excision, but was not associated with higher rate of uninterpretability.

Easy M Our immune systems can produce a vastly diverse repertoire of antibody molecules that each recognize and bind to a specific foreign antigen via a hypervariable region. However, there are a few bacterial antigens—such as Protein A, Protein G, and Protein L—that instead bind to the antibody's conserved regions and can bind to a large number of different antibodies. These high-affinity broad-spectrum antibody-binding properties have been widely exploited both in the laboratory and in industry for purifying, immobilizing, and detecting antibodies. Grover et al. (p. 656 ) have now identified Protein M found on the surface of human mycoplasma, which displays even broader antibody-binding specificity. The crystal structure of Protein M revealed how Protein-M binding blocks the antibody's antigen binding site. This mechanism may be exploited by mycoplasma to escape the humoral immune response.

Loss of cystic fibrosis transmembrane conductance regulator (CFTR) function reduces chloride secretion and increases sodium uptake, but it is not clear why CFTR mutation also results in progressive lung inflammation and infection. We previously demonstrated that CFTR-silenced airway cells migrate more slowly during wound repair than CFTR-expressing controls. In addition, CFTR-deficient cells and mouse models have been reported to have altered sphingolipid levels. Here, we investigated the hypothesis that reduced migration in CFTR-deficient airway epithelial cells results from altered sphingolipid composition. We used cell lines derived from a human airway epithelial cell line (Calu-3) stably transfected with CFTR short hairpin RNA (CFTR-silenced) or nontargeting short hairpin RNA (controls). Cell migration was measured by electric cell substrate impedance sensing (ECIS). Lipid analyses, addition of exogenous glycosphingolipids, and immunoblotting were performed. We found that levels of the glycosphingolipid, GM1 ganglioside, were ∼60% lower in CFTR-silenced cells than in controls. CFTR-silenced cells exhibited reduced levels of activated β1-integrin, phosphorylated tyrosine 576 of focal adhesion kinase (pFAK), and phosphorylation of Crk-associated substrate (pCAS). Addition of GM1 (but not GM3) ganglioside to CFTR-silenced cells restored activated β1-integrin, pFAK, and pCAS to near control levels and partially restored (∼40%) cell migration. Our results suggest that decreased GM1 in CFTR-silenced cells depresses β1-integrin signaling, which contributes to the delayed wound repair observed in these cells. These findings have implications for the pathology of cystic fibrosis, where altered sphingolipid levels in airway epithelial cells could result in a diminished capacity for wound repair after injury.