Changes in Levels of Nerve Growth Factor in Nasal Secretions after Capsaicin Inhalation in Patients with Airway Symptoms from Scents and Chemicals

Patients complaining of upper and lower airway symptoms caused by scents and chemicals have previously been shown to have increased cough sensitivity to inhaled capsaicin, but the precise mechanisms behind this reaction are unknown. Hypothesizing that a neurochemical alteration related to sensory hyperreactivity (SHR) of the airway mucosa occurs, we measured levels of nerve growth factor (NGF) in nasal lavage fluid (NAL) before and after capsaicin inhalation provocations and related the capsaicin cough sensitivity to the NGF levels. Thirteen patients with SHR and 14 control subjects were provoked with capsaicin inhalation at three different doses. We measured NGF in NAL before and after provocation and recorded cough and capsaicin-induced symptoms. All subjects demonstrated a dose-dependent cough response to capsaicin inhalation, with a more pronounced effect in patients than in controls. Basal levels of NGF were significantly lower in the patient group than in the control subjects (p < 0.01). After capsaicin provocation, the patients showed a significant increase in NGF (p < 0.01), which was related to capsaicin cough sensitivity. The findings demonstrate that, in patients with airway symptoms induced by scents and chemicals, SHR is real and measurable, demonstrating a pathophysiology in the airways of these patients compared to healthy subjects

Chemosensory interaction: acquired olfactory impairment is associated with decreased taste function

Olfaction, taste and trigeminal function are three distinct modalities. However, in daily life they are often activated concomitantly. In health and disease, it has been shown that in two of these senses, the trigeminal and olfactory senses, modification of one sense leads to changes in the other sense and vice versa. The objective of the study was to investigate whether and (if so) how, the third modality, taste, is influenced by olfactory impairment. We tested 210 subjects with normal (n=107) or impaired (n=103) olfactory function for their taste identification capacities. Validated tests were used for olfactory and gustatory testing (Sniffin' Sticks, Taste Strips). In an additional experiment, healthy volunteers underwent reversible olfactory cleft obstruction to investigate short-time changes of gustatory function after olfactory alteration. Mean gustatory identification (taste strip score) for the subjects with impaired olfaction was 19.4±0.6 points and 22.9±0.5 points for those with normal olfactory function (t=4.6, p<0.001). The frequencies of both, smell and taste impairments interacted significantly (Chi2, F=16.4, p<0.001), and olfactory and gustatory function correlated (r 210=0.30, p<0.001). Neither age nor olfactory impairment cause effects interfered with this olfactory-gustatory interaction. In contrast, after short-lasting induced olfactory decrease, gustatory function remained unchanged. The present study suggests that longstanding impaired olfactory function is associated with decreased gustatory function. These findings seem to extend previously described mutual chemosensory interactions also to smell and taste. It further raises the question whether chemical senses in general decrease mutually after acquired damag

rec. a M. Laroche, La Découverte de l'Amérique par les Américains

The effects of two sympathomimetic drugs on mucociliary activity and mucosal blood flow in the rabbit maxillary sinus were investigated by using a photo-electric technique (mucociliary activity) and laser Doppler flowmetry (blood flow). The responses produced were compared with effects of ligation of the external carotid artery. The alpha 1-agonist phenylpropanolamine (0.1-100 micrograms/kg) had no effect on the mucociliary activity, whereas the blood flow was reduced by 33.8 +/- 8.9% (mean +/- SE) when the dose was 100 micrograms/kg. The alpha 2-agonist xylometazoline (0.01-10.0 micrograms/kg) reduced mucociliary wave frequency by 21.6 +/- 4.6% (mean +/- SE) (maximum) for the dose 10 micrograms/kg. The blood flow was reduced by xylometazoline in the interval 1.0 to 10.0 micrograms/kg, with a maximum decrease of 65.8 +/- 2.6% (mean +/- SE) for the dose of 10 micrograms/kg. Ligature of the external carotid artery reduced blood flow by 76.0 +/- 4.6% (mean +/- SE), but did not significantly influence the mucociliary wave frequency. It is concluded that the decrease in mucociliary activity induced by alpha 2-adrenoceptor agonists is not due to a reduced blood flow

A family-based genome-wide association study of chronic rhinosinusitis with nasal polyps implicates several genes in the disease pathogenesis

Background: The pathogenesis of chronic rhinosinusitis with nasal polyps is largely unknown. Previous studies have given valuable information about genetic variants associated with this disease but much is still unexplained. Our goal was to identify genetic markers and genes associated with susceptibility to chronic rhinosinusitis with nasal polyps using a family-based genome-wide association study. Methods: 427 patients (293 males and 134 females) with CRSwNP and 393 controls (175 males and 218 females) were recruited from several Swedish hospitals. SNP association values were generated using DFAM (implemented in PLINK) and Efficient Mixed Model Association eXpedited (EMMAX). Analyses of pathway enrichment, gene expression levels and expression quantitative trait loci were then performed in turn. Results: None of the analysed SNPs reached genome wide significant association of 5.0 x 10-(8). Pathway analyses using our top 1000 markers with the most significant association p-values resulted in 138 target genes. A comparison between our target genes and gene expression data from the NCBI Gene Expression Omnibus database showed significant overlap for 36 of these genes. Comparisons with data from expression quantitative trait loci showed the most skewed allelic distributions in cases with chronic rhinosinusitis with nasal polyps compared with controls for the genes HLCS, HLA-DRA, BICD2, VSIR and SLC5A1. Conclusion: Our study indicates that HLCS, HLA-DRA, BICD2, VSIR and SLC5A1 could be involved in the pathogenesis of chronic rhinosinusitis with nasal polyps. HLA-DRA has been associated with chronic rhinosinusitis with nasal polyps in previous studies and HLCS, BICD2, VSIR and SLC5A1 may be new targets for future research

A family-based genome-wide association study of chronic rhinosinusitis with nasal polyps implicates several genes in the disease pathogenesis.

The pathogenesis of chronic rhinosinusitis with nasal polyps is largely unknown. Previous studies have given valuable information about genetic variants associated with this disease but much is still unexplained. Our goal was to identify genetic markers and genes associated with susceptibility to chronic rhinosinusitis with nasal polyps using a family-based genome-wide association study.427 patients (293 males and 134 females) with CRSwNP and 393 controls (175 males and 218 females) were recruited from several Swedish hospitals. SNP association values were generated using DFAM (implemented in PLINK) and Efficient Mixed Model Association eXpedited (EMMAX). Analyses of pathway enrichment, gene expression levels and expression quantitative trait loci were then performed in turn.None of the analysed SNPs reached genome wide significant association of 5.0 x 10-8. Pathway analyses using our top 1000 markers with the most significant association p-values resulted in 138 target genes. A comparison between our target genes and gene expression data from the NCBI Gene Expression Omnibus database showed significant overlap for 36 of these genes. Comparisons with data from expression quantitative trait loci showed the most skewed allelic distributions in cases with chronic rhinosinusitis with nasal polyps compared with controls for the genes HLCS, HLA-DRA, BICD2, VSIR and SLC5A1.Our study indicates that HLCS, HLA-DRA, BICD2, VSIR and SLC5A1 could be involved in the pathogenesis of chronic rhinosinusitis with nasal polyps. HLA-DRA has been associated with chronic rhinosinusitis with nasal polyps in previous studies and HLCS, BICD2, VSIR and SLC5A1 may be new targets for future research

Olfactory dysfunction in chronic stroke patients

Background: The aim of the study was to investigate odor identification performance in patients one year after hospital admittance due to stroke. Predictors for olfactory dysfunction were investigated as well as self-reported olfactory function and pleasantness of olfactory items. Methods: A 1-year prospective study was performed. Stroke location, classification and comorbidities were registered at hospital admission. One year after admission, olfactory function was assessed using standardized olfactory methods (screening for loss of detection sensitivity and an odor identification test). A group of matched controls was derived from a population-based study to compare odor identification performance between groups. Patients were asked for their personal judgment regarding their olfactory function and pleasantness of odorous items. In addition, global cognitive function and symptoms of depression were assessed. Results: A total of 78 patients were enrolled (46 males, 32 females; mean age 68 years) of which 28.2 % exhibited reduced olfactory function (hyposmia) and 15.4 % exhibited loss of olfactory function (10.3 % functional anosmia, 5.1 % complete anosmia). Patients showed significantly lower olfactory performance compared to age- and sex-mated matched controls. Predictors of impaired olfactory function were age and NIHSS score. Self-reports indicated no significant differences between patients with normal olfactory function and those with reduced function. Yet, patients having an olfactory dysfunction rated odorous items as significantly less pleasant compared to patients without dysfunction. Conclusions: Olfactory dysfunction seems to occur frequently after stoke even one year after initial admission. The deficits seem to relate to hyposmia and functional anosmia, and less to a complete loss of smell sensitivity.Errata: Wehling E, Naess H, Wollschlaeger D, Hofstad H, Bramerson A, Bende M, et al. Olfactory dysfunction in chronic stroke patients. BMC Neurol. 2015;15:199. DOI 10.​1186/​s12883-015-0463-5.</p

Changes in Levels of Nerve Growth Factor in Nasal Secretions after Capsaicin Inhalation in Patients with Airway Symptoms from Scents and Chemicals-1

<p><b>Copyright information:</b></p><p>Taken from "Changes in Levels of Nerve Growth Factor in Nasal Secretions after Capsaicin Inhalation in Patients with Airway Symptoms from Scents and Chemicals"</p><p>Environmental Health Perspectives 2005;113(7):849-852.</p><p>Published online 17 Mar 2005</p><p>PMCID:PMC1257644.</p><p>This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original DOI.</p