Search PubMed⌕ Search

Biomedical subjects

M Ohm

Publications and source records attributed to M Ohm.

4 recordsLinked to original sources
PubMed2001

Nasal nitric oxide and the nasal cycle.

OBJECTIVES: To establish the relationship between nasal patency and the nitric oxide (NO) concentration in the nasal airways. METHODS: Unilateral nasal NO concentration (n = 11) and inhaled nasal NO concentration at oropharynx (n = 9) were measured in healthy adult volunteers. Subjects breathed normally through the nose with a known resistance (ranged from none to total occlusion) placed in one nostril. In a subgroup (n = 7), the unilateral nasal NO concentrations were determined with nasal cavity congestion induced by lateral decubitus. RESULTS: When the added nasal resistance was less than 6 cm H(2)0 per liter per second, the peak NO concentrations in the nose remained below 80 parts per billion (ppb). Thereafter, the higher the resistance, the greater the NO concentration. It was up to 1109.7 ppb when the front nostril was totally occluded. There was no correlation between oropharyngeal NO concentrations and resistance in the front of the nose (r = 0.4). There was a significantly negative correlation between nasal cavity volumes and nasal NO concentrations (r = -0.8, P <.001). CONCLUSIONS: Increases in nasal resistance to levels encountered in the nasal cycle and in recumbency augments the NO concentration within the obstructed side of the nose. Although that within the nose changes with patency, the NO concentration is constant down to the lower airways. The modulation role of the upper airways to the inhaled NO concentration remains unclear.

Adult↗
PubMed1993

Nasal hyperreactivity. A histamine provocation model.

The aim of the study was to see whether it is possible to select non-allergic persons with hyperreactivity, especially in the nose, from healthy individuals with a histamine standardization test. Another aim was to elucidate whether a so-called priming effect could be present in such a non-allergic disorder. Seven patients with a history of perennial rhinitis, expressed as either or both swelling or discharge from the nose and a negative allergic investigation, were examined on three up to seven consecutive occasions. Rhinostereometry was used to register the reaction in the mucous membrane to a solution of histamine in successively increased concentrations. The results showed a statistically significant difference between this group compared with a control group of healthy volunteers. We could not detect any increase in the sensitivity during repeated provocations.

Adolescent↗
PubMedDate not supplied

Nasal histamine provocation of tenants in a sick-building residential area.

Health problems associated with the indoor climate have aroused an increasing scientific interest, and the term "sick-building syndrome" (SBS), which describes the most frequent symptoms in this context, has been coined. However, it has been difficult to demonstrate objectively any pathophysiological changes in the subjects affected. Thirty-three healthy and nonatopic persons were randomly selected on the basis of answers in a postal questionnaire dealing with discomfort or health symptoms experienced in their home environment. Twenty-three lived in a residential area with indoor climate problems (SBS area) and 10 lived in an area without climate problems (non-SBS area). Twelve persons from the SBS area reported nasal symptoms, which they ascribed to their home environment. The remaining 11 persons from the same area, as well as the 10 subjects from the non-SBS area, had no nasal distress. They were examined with rhinostereometry during histamine provocation. Hyperreactivity, defined as mucosal swelling exceeding 0.4 mm at 5 and 10 minutes after provocation with 0.14 ml of 2 mg/ml histamine chloride, was frequent in the symptomatic SBS group as well as in the asymptomatic SBS group. The analysis of the increment of mucosal swelling for the whole range of histamine chloride concentrations (0.1 mg/ml to 16 mg/ml) showed significantly different growth curves for the three groups in the residential areas and an external reference group, (p < 0.0001). Subjects living in the SBS area were prone to nasal hyperreactivity, whether they reported symptoms from the upper airways or not. The results support the hypothesis that living in an SBS area increases the risk of developing nonspecific nasal hyperreactivity.

Adult↗