Detection of rotavirus- and norovirus-specific IgG memory B cells in tonsils.

Because rotavirus (RV) and norovirus (NoV) are transmitted through the fecal-oral route, tonsils due to their location within the oropharynx may sample or become infected with these viruses. We investigated if RV and NoV RNA/antigen, or virus-specific memory/plasma B cells can be detected in the tonsils. While neither RV/NoV antigen, nor genomic RNA was detected, 90% (27/30) of tonsils tested had RV- and NoV-specific IgG memory B cells. However, the mechanism explaining how these cells get there (whether because of local induction or homing after induction at other sites) and the role these cells might play during active infection is not yet clear.

Vestibular Function After Cochlear Implantation: A Comparison of Three Types of Electrodes.

OBJECTIVE: To investigate the vestibular function after cochlear implantation with different types of electrode arrays. STUDY DESIGN: Retrospective cohort study. SETTING: Academic tertiary referral center. MATERIALS AND METHODS: Forty three adults underwent first cochlear implantation. Three consecutive series of patients: Group 1 (n = 13) implanted with a precurved electrode, Group 2 (n = 15) implanted with a straight electrode, Group 3 (n = 15) implanted with a flexible electrode. Patient's vestibular functions were assessed with pre- and postoperative caloric testing using videonystagmography (VNG). The postoperative reduction of the maximum slow phase velocity (MSPV) in the implanted ear was evaluated. Medical charts were reviewed to evaluate the occurrence of late onset of postoperative vestibular symptoms. RESULTS: Mean reduction of MSPV was 7.6/s (standard deviation [SD] 8.0) in Group 1, 23.1/s (SD 16.6) in Group 2, and 0.1/s (SD 18.5) in Group 3. Significant difference was found between Group 1 and 2 (p < 0.030) and between Group 2 and 3 (p < 0.001). Group 2 showed a higher prevalence of late onset of clinical vertigo (28.6%) than Group 1 (7.7%) and 3 (6.7%). CONCLUSION: In this prospective study, significantly larger reductions of caloric responses were found in subjects implanted with a straight electrode compared with subjects implanted with a precurved or flexible electrode. These findings seem to correlate to a higher prevalence of postoperative vertigo.