The composition of house dust mite is critical for mucosal barrier dysfunction and allergic sensitisation

BACKGROUND

House dust mite (HDM) allergens have been reported to increase airway epithelial permeability, thereby facilitating access of allergens and allergic sensitisation.

OBJECTIVES

The authors aimed to understand which biochemical properties of HDM are critical for epithelial immune and barrier responses as well as T helper 2-driven experimental asthma in vivo.

METHODS

Three commercially available HDM extracts were analysed for endotoxin levels, protease and chitinase activities and effects on transepithelial resistance, junctional proteins and pro-inflammatory cytokine release in the bronchial epithelial cell line 16HBE and normal human bronchial cells. Furthermore, the effects on epithelial remodelling and airway inflammation were investigated in a mouse model.

RESULTS

The different HDM extracts varied extensively in their biochemical properties and induced divergent responses in vitro and in vivo. Importantly, the Greer extract, with the lowest serine protease activity, induced the most pronounced effects on epithelial barrier function and CCL20 release in vitro. In vivo, this extract induced the most profound epithelial E-cadherin delocalisation and increase in CCL20, CCL17 and interleukin 5 levels, accompanied by the most pronounced induction of HDM-specific IgE, goblet cell hyperplasia, eosinophilic inflammation and airway hyper-reactivity.

CONCLUSIONS

This study shows the ability of HDM extracts to alter epithelial immune and barrier responses is related to allergic sensitisation but independent of serine/cysteine protease activity.

Four close bupranolol analogues are antagonists at the low-affinity state of beta1-adrenoceptors

Bupranolol is an antagonist at the cardiostimulatory low-affinity state of b(1)-adrenoceptors and we were interested whether this effect is shared by its fluorine (GD-6), methyl (DZ-51) and isopropyl analogue (DZ-13) and by the analogue hydroxylated at the tertiary butyl moiety (DZ-52). (-)-Bupranolol and compounds (-)-GD-6, (+)-GD-6, (-)-DZ-13, (+)-DZ-13, DZ-51 and DZ-52 antagonized the CGP 12177-induced tachycardia in pithed rats with "apparent pA(2) values" of 6.1, 6.1, 4.6, 5.5, 4.6, 5.1 and 5.3, respectively. For comparison, their potencies and affinities at the high-affinity state of b(1)-adrenoceptors were determined, using the xamoterol-induced tachycardia in pithed rats and [(3)H]CGP 12177 binding to rat cerebrocortical membranes. The respective "apparent pA(2) values" in the functional experiments were 7.9, 8.1, 5.4, 8.4, 5.7, 7.3 and 6.8 and the pK(i) values in the binding experiments were 8.8, 8.4, 6.9, 8.5, 6.7, 8.4 and 8.2. In conclusion, (-)-bupranolol and its fluorine analogue (-)-GD-6 are equipotent at the low-affinity state of beta(1)-adrenoceptors. The stereoselectivity of GD-6 and DZ-13 suggests that the low-affinity state is indeed a receptor.

Virodhamine relaxes the human pulmonary artery through the endothelial cannabinoid receptor and indirectly through a COX product

BACKGROUND AND PURPOSE

The endocannabinoid virodhamine is a partial agonist at the cannabinoid CB(1) receptor and a full agonist at the CB(2) receptor, and relaxes rat mesenteric arteries through endothelial cannabinoid receptors. Its concentration in the periphery exceeds that of the endocannabinoid anandamide. Here, we examined the influence of virodhamine on the human pulmonary artery.

EXPERIMENTAL APPROACH

Isolated human pulmonary arteries were obtained during resections for lung carcinoma. Vasorelaxant effects of virodhamine were examined on endothelium-intact vessels precontracted with 5-HT or KCl.

KEY RESULTS

Virodhamine, unlike WIN 55,212-2, relaxed 5-HT-precontracted vessels concentration dependently. The effect of virodhamine was reduced by endothelium denudation, two antagonists of the endothelial cannabinoid receptor, cannabidiol and O-1918, and a high concentration of the CB(1) receptor antagonist rimonabant (5 muM), but only slightly attenuated by the NOS inhibitor L-NAME and not affected by a lower concentration of rimonabant (100 nM) or by the CB(2) and vanilloid receptor antagonists SR 144528 and capsazepine, respectively. The COX inhibitor indomethacin and the fatty acid amide hydrolase inhibitor URB597 and combined administration of selective blockers of small (apamin) and intermediate and large (charybdotoxin) conductance Ca(2+)-activated K(+) channels attenuated virodhamine-induced relaxation. The vasorelaxant potency of virodhamine was lower in KCl- than in 5-HT-precontracted preparations.

CONCLUSIONS AND IMPLICATIONS

Virodhamine relaxes the human pulmonary artery through the putative endothelial cannabinoid receptor and indirectly through a COX-derived vasorelaxant prostanoid formed from the virodhamine metabolite, arachidonic acid. One or both of these mechanisms may stimulate vasorelaxant Ca(2+)-activated K(+) channels.

Potential involvement of a propranolol-insensitive atypical beta-adrenoceptor the vasodilator effect of cyanopindolol in the human pulmonary artery

The aim of our study was to examine whether non beta(1)-/beta(2)-adrenoceptors participate in the relaxation of the human pulmonary artery. For this purpose the vasodilatory effect of the non-conventional partial beta-adrenoceptor agonist cyanopindolol was examined. Cyanopindolol (1-300 microM), studied in the presence of the beta(1)-/beta(2)-adrenoceptor antagonist propranolol, relaxed the human pulmonary artery preconstricted with serotonin 1 microM in a concentration-dependent manner (maximally by about 80%). This effect was diminished by bupranolol 10 microM (an antagonist of beta(1)-beta(3)-adrenoceptors and the low affinity state of the beta(1)-adrenoceptor) and CGP 20712 10 microM (known to antagonize the low-affinity state of the beta(1)-adrenoceptor at high concentrations). In further experiments, the effect of beta-adrenoceptor ligands on the serotonin-induced vasoconstriction was examined. The concentration-response curve for serotonin was not affected by cyanopindolol 30 microM, bupranolol 10 microM and CGP 20712 10 microM but shifted to the right by cyanopindolol 100 and 300 microM; the serotonin 5-HT(2A) receptor antagonist ketanserin 0.3 microM abolished the maximum contraction elicited by serotonin. In conclusion, the present study reveals that the vasodilatory effect of cyanopindolol in the human pulmonary artery consists of two components, i.e. activation of a propranolol-insensitive atypical beta-adrenoceptor and antagonism against 5-HT(2A) receptors.

[Foreign body in the right frontal lobe of the brain as a result of right eyeball and right eye-socket trauma--case report]

We report a case of a 44 year old man, who was admitted to our hospital because of right eyeball and right eye-socket due to a piece of diamond circular saw. Right eyeball was sutured. CT--examination showed a metallic foreign body in the right frontal lobe of brain. Metallic foreign body, which damaged the right eyeball, caused upper restriction of right eye-socket ceiling and stuck in a frontal lobe of the brain was removed.

[Content of nitrates and nitrites in raw mild in different regions of the country]

The content of nitrates and nitrites in raw milk in different regions of the country was studied. The results obtained dependent both on the factory from which the samples origin and on the seasons of the year. In 37% of samples there was insignificant increase in the level of nitrates, and in 31.9 of nitrites.

[Etiology and clinical course of purulent meningitis and encephalitis in adults]

The authors, basing on the own experience in the treatment of 578 patients with purulent meningitis and encephalitis, discuss etiologic and clinical problems as an early diagnosis of the cause decides on the proper therapy and often on the patient's fate. The authors are convinced that the result of general CSF examination is a crucial diagnostic criterion in meningitis and encephalitis but does not permit identification of the disease causes. Problems with etiological verification is discussed. The authors have found that the infection with N. meningitidis and S. pneumoniae remains the most frequent cause of the disease in adults. However, the cause of the disease cannot be determined in over 50% of patients, and etiological verification of infections caused by H. influenzae and anaerobic organisms is quite unsatisfactory. The authors stress that over 20% of patients had skull injury and meningitis most frequently resulted from the infection with S. pneumoniae in these patients. It is suggested that purulent meningitis and encephalitis as a rule is endogenous disease produced by the activation of endogenous source of the infection.

[Methods and treatment results of purulent meningitis and encephalitis in adults--based on personal observations]

The authors present own methods and results of the treatment of 578 patients with suppurative meningitis and encephalitis. Etiologically most frequent infections due to N. meningitidis, S. pneumoniae, and H. influenzae were treated with penicillin and ampicillin; the authors recommend to replace the latter antibiotic with cefotaxime. If meningitis and encephalitis were due to aerobic gram-negative bacilli, a possibility of the simultaneous infection with anaerobic flora was considered, and the drugs active against both types of the organisms were administered. The same was the treatment in case of etiologically confirmed staphylococcal infection. In case of unknown etiology of meningitis and encephalitis therapy was based on clinical data, and laboratory findings.