Rat Model of Staphylococcal Enterotoxin B-Induced Rhinosinusitis

ObjectivesIt has been proposed that microbial persistence, superantigen (SA) production, and host T-cell response may be involved in the development of chronic rhinosinusitis. According to the SA hypothesis, a single intranasal application of SA such as staphylococcal enterotoxin B (SEB) may induce chronic eosinophilic rhinosinusitis. This study aimed to develop a rat model of rhinosinusitis induced by intranasally applied SEB.MethodsForty µL of SEB (100 µg/mL) or phosphate buffered saline was applied intranasally through each naris in 4 week-old Sprague-Dawley test rats (N=36) and controls (N=16), respectively. Following sacrifice at 1, 5, 14, and 28 days, the obtained nasal cavity and sinuses were prepared for histologic investigation. The histologic sections were examined in a blind manner for the ratio of the sinus spaces occupied by inflammatory cell clusters and the number of inflammatory cells in the lamina propria.ResultsInfiltration of neutrophils in the lamina propria and appearance of neutrophil clusters in the sinus spaces were observed in the SEB-applied rats. The ratio of the sinus spaces occupied by neutrophil clusters and the number of neutrophils infiltrated in the lamina propria increased significantly at day 1 as compared with the control rats.ConclusionIntranasally applied SEB induces acute neutrophilic rhinosinusitis in rats. Eosinophilic inflammation was not demonstrated. The mere presence of SA in the nose does not necessarily induce SA-induced inflammation, as suggested by the SA hypothesis

The Use of Mobile Applications to Monitor Sleep Quality and Alertness during Shift Work in Nurses: A Preliminary Study

Background and Objective Fatigue or inattentiveness in nurses during shift work affects patient safety. Therefore, sleep quality and alertness during shift work requires monitoring. The aims of this study were to: 1) compare sleep parameters measured using sleep logs and mobile sleep applications and 2) evaluate sleep quality and alertness during shift work using mobile applications. Methods Twenty shift-work nurses voluntarily enrolled in the study. We compared sleep parameters including time in bed (TIB), sleep latency (SL), total sleep time, and wakefulness after sleep onset, recorded using sleep logs and mobile applications. An additional 66 female shift-work nurses voluntarily evaluated their sleep quality and alertness at work using the ‘Sleep Time’ and ‘Math Quiz’ applications. Results TIB was significantly lower in night-shift nurses (328.3 ± 8.9) than in nurses working other shifts (395.3 ± 9.1 min; p < 0.05). SL was significantly lower after a night shift (26.1 ± 1.7 min; p < 0.05) than after a day shift (31.5 ± 1.9 min) or a day off (31.0 ± 1.4 min). The Math Quiz scores did not vary by shift type, but sleepiness scores were significantly higher immediately after waking up (5.57 ± 0.15) and during work (4.91 ± 0.14) in night-shift nurses, as compared to other nurses (p < 0.05). Conclusions Mobile applications and sleep logs were both effective in measuring sleep parameters. Most shift-work nurses, particularly those working nights, slept poorly. Mobile sleep and arithmetical applications are objective, reliable, and feasible means of monitoring the sleep quality and alertness of shift-work nurses

Age-related differences in human palatine tonsillar B cell subsets and immunoglobulin isotypes

The tonsils provide defense of the upper aerodigestive tract against pathogens. Although long known to undergo functional changes with age, the precise changes occurring within tonsillar B cell populations remain undefined. In the present study, we investigated age-related changes in palatine tonsillar B cell subsets and immunoglobulin (Ig) isotypes. Palatine tonsils were obtained from forty-two tonsillectomy patients without tonsillitis who were divided into three groups: young children (4–9&nbsp;years), adolescents (10–19&nbsp;years), and adults (20–60&nbsp;years). Tonsillar B cells were then analyzed by flow cytometry. Using expression of CD38 and IgD to define B cell subsets, we found that the frequency of germinal center (GC) B cells in the tonsils was significantly higher, and the frequency of memory B cells lower, in young children as compared to adolescents and adults. Within the GC B cell subsets, adults had a higher frequency of IgA+ cells and a lower frequency of IgM+ cells as compared to individuals in the younger age groups. Moreover, young children had a higher frequency of IgG+ cells in the GC B cell subsets than did individuals in the older age groups. We also observed an abundance of IgM+ cells among memory B cells and plasmablasts in young children and IgA+ cells in adults. In summary, the proportion of GC B cells in palatine tonsillar B cells decreases with age, while the proportion of memory B cells increases with age. In addition, Ig isotypes in tonsils preferentially switch from IgM to IgA as individuals age