Biomedical subjects

Tom Deutschle

Publications and source records attributed to Tom Deutschle.

4 recordsLinked to original sources

PubMed2005

Nasal cytologies--impact of sampling method, repeated sampling and interobserver variability.

The influence of sampling technique, repeated sampling and the interobserver variability on quantitative analysis of nasal cytologies were explored. Nasal cytologies from 12 healthy and 4 allergic volunteers were repeatedly collected with a total of three different sampling techniques. Cells were demonstrated by May-Grünwald-Giemsa staining and by immunostaining for CD45 and eosinophil peroxidase (EPO). To determine the interobserver variability specimens were evaluated by three observers with various levels of nasal cytology experience. When adjusted for the variability due to sampling method and repeated sampling, the staining index for CD45+ cells was 53.4 +/- 11% (interindividual coefficient of variation: 0.21) with an average intraindividual coefficient of variation of 0.14. For CD45, staining indices differed significantly between the washing techniques and the nasal swabs (p<0.01). Repeated sampling did significantly influence the staining indices of specimens collected with nasal swabs (p<0.05). Subjects with nasal allergy had less CD45+ cells in their nasal cytologies than the non-allergic subjects (p=0.02). A high level of compliance for the quantitative analysis of nasal cytologies between three observers was found (kappa(w) range 0.95-0.98). For studies that require repeated sampling, the lavage will be recommended as best suitable to obtain nasal cytologies.

Adult↗

PubMed2004

Short-term exposure to urban dust alters the mediator release of human nasal mucosa.

LEARNING OBJECTIVES: Identify any changes in cytokine (mediator) concentrations in nasal secretions after healthy individuals were experimentally exposed to urban dust. Recall what connection there was, if any, between post-exposure cytokine levels in nasal secretions on the one hand, and, on the other, counts of inflammatory cells and nasal symptoms. Report the investigators' conclusions as to whether exposure to urban dust is a cause of persistent inflammation and chronic airway disease. ABSTRACT: Thirty healthy volunteers were nasally exposed to control air and urban dust (SRM 1649a) in concentrations of 150 and 500 microg/m3 for 3 hours. Thirty minutes, 8 hours, and 24 hours after exposure, nasal cytologies were obtained, and nasal secretion levels of interleukin (IL)-1beta, IL-6, IL-8, tumor necrosis factor-alpha, epithelial neutrophil activating protein-78, monocyte chemoattractant protein-1, and substance P were determined. Twenty-four hours after exposure to 500 microg/m3, nasal secretion levels of IL-1beta increased 72.3% (0-150.2%, P=0.002), levels of IL-6 increased 42.2% (-28-161.9%,P=0.01), and levels of IL-8 increased 19.7% (-20.3-60.5%, P=0.03; median and 95% confidence interval). These cytokines correlated closely with nasal inflammatory cell counts. No exposure-related changes of tumor necrosis factor-alpha, monocyte chemoattractant protein-1, epithelial neutrophil activating protein-78, and substance P levels were observed. These results provide experimental support for recent epidemiological observations that short-term increase of outdoor particulate matter concentration increases the frequency of upper respiratory diseases.

Adult↗

PubMed2003

Effects of low-toxicity particulate matter on human nasal function.

Chronic nasal and paranasal sinus problems affect approximately 15% of the population in industrialized countries. Recent studies suggest that particulate matter might contribute to this condition. The effects of acute exposure to low-toxicity particulate matter on human nasal airflow, mucociliary transport, and nasal discomfort should be assessed. Thirty-two healthy volunteers were exposed to 0 (control), 500, 1000, and 5000 micrograms/m3 calcium carbonate dust for 3 hours and nasal saccharin transport time (STT), rhinomanometry, and visual analog scales (VAS) on nasal discomfort were obtained. A dose dependent decrease of STT (P = 0.02) and nasal patency (P = 0.04), and increased sensation of nasal obstruction (P = 0.002) and dryness (P = 0.03) was observed. The results indicate that acute exposure to low-toxicity particulate matter in concentrations frequently encountered in western agglomeration areas may affect nasal functions and cause nasal symptoms.

Adult↗

PubMedDate not supplied

Nasal toxicity of benzalkonium chloride.

BACKGROUND: Benzalkonium chloride (BAC) is added to nasal preparations to prevent microbial contamination. Adverse effects of BAC on human nasal mucosa should be evaluated. METHODS: The ciliotoxicity of BAC was assessed in isolated human nasal epithelia from 15 donors. The effects of nasal BAC 0.05% (4 x 200 microL/day for 8 days) on nasal saccharin transport time, inflammatory cells and cytokine levels in nasal secretions, and nasal symptom scores were assessed in a randomized, double-blind crossover trial in 16 healthy volunteers. RESULTS: In vitro, BAC was ciliotoxic (p < 0.0001). In vivo, BAC did not alter saccharin transport time in healthy individuals (p > 0.8). No BAC-associated proinflammatory effects were observed. The staining index for myeloperoxidase was 4.8% in the placebo period and 6.3% (p = 0.42) in the BAC period. Also, nasal secretion levels of cytokines and the neuropeptide substance P revealed no BAC-associated differences. Concentrations for interleukin (IL)-6 in the placebo period were 41.5 pg/mL (0.9-91.7 pg/mL) and in the BAC period were 17.6 pg/mL (3.2-65.9 pg/mL; p = 0.46), and concentrations for substance P were 119 pg/mL (58-293 pg/mL) and 131 pg/mL (80-330 pg/mL; p = 0.31), respectively. Immediately after application, BAC caused nasal irritation (p = 0.001), a burning sensation (p = 0.0003), and hypersecretion (p = 0.006). Moreover, BAC caused a persistent sensation of nasal irritation (p < 0.01). CONCLUSION: BAC in concentrations used in nasal preparations is ciliotoxic. In healthy individuals, the ciliotoxic effect of BAC is neutralized, probably by components of nasal secretions. No BAC-related proinflammatory effects have been observed. At higher doses than normally used therapeutically, BAC caused significant nasal irritation.

Adult↗