Label-free electrochemical biosensor for direct detection of Oncostatin M (OSM) inflammatory bowel diseases (IBD) biomarker in human serum.

Oncostatin M (OSM) is an interleukin-6 (IL-6) member family cytokine implicated in the pathogenesis of chronic diseases including inflammatory bowel disease (IBD). OSM is a novel diagnostic biomarker over-expressed in the serum of IBD patients. This paper reports on the first electrochemical OSM immunosensor, developed using a multistep fabrication process aimed at covalently immobilizing OSM antibodies on a mixed self-assembled monolayer coated gold working electrode. Cyclic voltammetry, atomic force microscopy (AFM), IR spectroscopy and optical characterizations were used to validate the sensor functionalization protocol. Electrochemical impedance spectroscopy (EIS) measurements were performed to assess the reliability of the immunosensor preparation and to verify the antibody-antigen complexes formation. The label-free immunosensor showed high sensitivity identifying OSM at clinically relevant concentrations (37-1000 pg mL-1) with low detection limit of 2.86 pg mL-1. Both sensitivity and selectivity of the proposed immunosensor were also demonstrated in human serum in the presence of interfering biomarkers, making it an innovative potential platform for the OSM biomarker detection in IBD patients' serum.

Evaluation of monocyte chemotactic responsiveness in uraemic patients undergoing haemodialysis with different dialytic membranes.

Recent data show that monocyte chemotactic peptide-1 (MCP-1), a chemotactic factor specific for monocytes, may play a central role in regulating the activation of these cells. For this reason, the production of MCP-1 in peripheral blood mononuclear cell (PBMC) cultures of eight healthy subjects, six chronic uraemic subjects under conservative treatment and six chronic uraemic patients undergoing haemodialysis (HD), was assessed. In the latter group of individuals, complement-activating membranes such as cuprophan (CU) were used for 1 month followed by biocompatible non-complement-activating membranes, like polymethylmetacrylate (PMMA) for the next 30 days. The chemotactic index (CI) elicited by PBMC supernatants from patients undergoing dialysis was found to be significantly higher than that obtained by supernatants recovered from normal subjects or uraemic patients on conservative therapy. Furthermore, the CI from PBMC supernatants having had contact with CU membranes was higher than that obtained from PBMC activated by PMMA. Finally, the increased chemotactic ability in the supernatants was closely correlated with the augmented MCP-1 gene expression and production, as assessed by in vitro hybridization studies.

Modulation of eosinophilic chemotaxis with azelastine and budesonide in allergic patients.

In this paper, the effect of azelastine hydrochloride, a potent inhibitor of leukotrienes (LTs) and H1 receptors for histamine, was assessed as regards modulation of in vitro eosinophilic chemotaxis. In this respect, chemotaxis of eosinophils (EOS), isolated from the peripheral blood of untreated allergic subjects in the acute phase, was significantly diminished after in vitro treatment with azelastine in comparison to values before treatment. When EOS were pre-incubated with serial dilutions of the drug, it was observed that azelastine inhibited chemotaxis in a dose-dependent fashion. Since azelastine acts in vitro as a regulator of the calcium pump, EOS were pre-incubated with different concentrations (0.6 and 3.0 mM) of Ca++. In these experimental conditions azelastine was able to reduce EOS chemotactic activity only in the presence of 0.6 mM Ca++, whereas with higher Ca++ concentrations (3.0 mM) the inhibitory effect of the drug was abrogated. On the other hand, particular attention was paid to inhaled budesonide, a non halogenated glucocorticosteroid derivative, structurally related to 16 alpha-hydroxy prednisolone, which represents a helpful for treatment mild to moderate asthma. Data obtained after in vitro treatment with budesonide of a group of allergic patients demonstrated that EOS chemotactic activity was significantly reduced in these subjects. Conclusively our data show that 1) azelastine acts as a dose-dependent antagonist of chemotaxis; 2) it may exert this action by inhibiting Ca++ flow into cells; 3) inhaled budesonide may induce inhibition of bronchial inflammation by downregulating EOS chemotactic capacity.

Retrospective study on fluticasone propionate aqueous nasal spray efficacy in patients with allergic rhinitis: evaluation of clinical and laboratory parameters.

BACKGROUND: In allergic rhinitis, allergenic stimulation causes the release of various mediators that induce symptoms and the development of chronic inflammation, which, in turn, is caused by cells involved in the late phase of inflammation, such as eosinophils. The eosinophils also cause damage at the mucosal level through the secretion of eosinophil cationic protein and other preformed factors contained in their granules. The objective was to verify the efficacy of fluticasone propionate aqueous nasal spray in patients with allergic rhinitis; in a retrospective study, we have evaluated mediators of inflammation, making correlations with the clinical symptoms score during and outside the pollen season. METHODS: Forty patients with allergic rhinitis and 15 normal controls were included in our study. Eosinophil cationic protein, eosinophil chemotactic activity, and blood and nasal lavage eosinophil count were evaluated as laboratory parameters. RESULTS: We found a significant increase in nasal lavage levels of eosinophil cationic protein in allergic patients, and this was strictly correlated with the clinical symptoms score. No differences were found in the eosinophil count of allergic patients and in the serum eosinophil cationic protein of patients sensitized to seasonal allergens in comparison with normal subjects. By contrast, an increase in serum eosinophil cationic protein level was found in patients sensitized to perennial allergens. After topical administration of fluticasone propionate aqueous nasal spray, a reduction in nasal lavage eosinophil cationic protein secretion was obtained with a reduction of eosinophil chemotactic activity at the local level. This reduction correlated with an improvement of clinical symptoms. CONCLUSIONS: The clinical improvement and reduction in nasal lavage eosinophil cationic protein and eosinophil chemotactic activity after administration of fluticasone propionate aqueous nasal spray further confirms the role of this treatment in allergic rhinitis.

Alternative glucocorticoids for use in cases of adverse reaction to systemic glucocorticoids: a study on 10 patients.

BACKGROUND: Reactions to systemically administered corticosteroids are rare, despite their widespread use. OBJECTIVES: To identify alternative glucocorticoids for emergency use in patients with adverse reactions to systemic glucocorticoids. METHODS: Ten patients were identified as having adverse reactions after the use of systemic corticosteroids. Skin prick tests and intradermal tests to hydrocortisone (HC) and methylprednisolone (MP), and intradermal tests to betamethasone and dexamethasone, were performed in all patients, and oral challenge tests to betamethasone (n=10) and deflazacort (n=6). RESULTS: Skin prick tests were negative in all patients, whereas intradermal tests to HC and MP were positive in eight; two patients showed only an isolated cutaneous sensitivity to MP. Intradermal tests to betamethasone and dexamethasone were negative, and oral challenge tests were negative in all patients. CONCLUSIONS: Our results suggest the possibility of an IgE-mediated mechanism for allergic reactions to HC and MP, probably due, at least in part, to a steroid-glyoxal. We suggest that betamethasone and deflazacort could be reserved for emergency use in patients with adverse reactions to other corticosteroids.

Eyedrop-induced allergy: clinical evaluation and diagnostic protocol.

BACKGROUND: In the last few years, adverse reactions to mydriatic eyedrops have been investigated. However, is not still available a standardized protocol, capable of identify the pathogenetic mechanism. In the light of these findings we have evaluated the reliability of a protocol with well established concentration of specific allergens. METHODS: The diagnostic method includes the application of patch test series Gruppo Italiano Ricerca Dermatiti da Contatto e Ambientali (GIRDCA), medicaments, corticosteroids, local anesthetics, main eyedrops' excipients, pure active principles and extemporaneous preparations with mydriatic eyewashes. At the same time, skin prick test with a solution of atropine sulfate at 1 per thousand and an intradermal test with injection of atropine at 0.01 per thousand were carried out. RESULTS: After patch tests were removed, we detected seven positiveness to the phenylephrine, two to the benzalkonium chloride, one to thiomersal, one to the ethylendiamine and one to the atropine sulfate 1 per thousand. With intradermal tests we obtained three positiveness in patients who reported adverse reactions to atropine. CONCLUSIONS: Our results show that phenylephrine is frequently responsible for allergic conjunctivitis (53.8%). In the case of atropine, even though the limited number of patients suggests to perform more extensive studies, it emerges that our diagnostic protocol is safe and might be able to screen allergic reactions in the field of ophthalmopathies.

Retrospective study of adverse reactions to non steroid anti-inflammatory drugs (NSAIDs): predictive value of controlled challenge with alternative drugs.

Acetylsalicylic acid (ASA) and NSAIDs, which inhibit the cyclo-oxygenase enzyme (C-O), are responsible, when administered at therapeutic doses, for adverse reactions mainly involving the skin and respiratory tract. The prevalence of intolerance to ASA and NSAIDs, assessed by the Section of Allergic and Immunological Diseases at the University of Bari on a population of 15,800 patients referred for allergic diseases over a period of 7 years, was found to be 11.4%. The adverse reactions to NSAIDs observed were in most cases skin complaints (88.9%), followed by respiratory symptoms (asthma +/- rhinitis, rhinitis) and general symptoms (shock, hypotension, lipothymia). The most common types of NSAIDs taken were pyrazolones, salicylics, arylpropionics, paracetamol. Controlled oral challenges with alternative NSAIDs (especially nimesulide) confirm the predictive power of this test: in fact, among patients who showed tolerance to the challenge drug, only 10.6% manifested unexpected reactions during the course of one year's follow-up.

Contact dermatitis in students practicing sports: incidence of rubber sensitisation.

BACKGROUND: Over the last few years, changes in cutaneous homoeostasis resulting from sports activities have been reported. In particular, alterations in sweating mechanisms, the hydrolipid barrier, and surface bacterial flora, together with exposure to atmospheric conditions and the need to use medicaments, detergents, and other topical substances, predispose subjects to allergic contact dermatitis. OBJECTIVE: To evaluate the incidence of allergic contact dermatitis in a group of young people practising sports activities. METHODS: Patch tests were performed to confirm the diagnosis of irritant or allergic dermatitis; in addition, the radioallergoabsorbent test (RAST) to latex was evaluated in the group studied. RESULTS: Allergic contact dermatitis caused by thiourams (23.3%) and mercaptobenzothiazole (20.9%) was prevalent. Other haptens, such as benzocaine and nickel, which are contained in clothing, equipment, topical medicaments, and creams used for massage, were also allergenic. In two cases, RAST positivity to latex was registered. CONCLUSIONS: -The results suggest that close contact with sports equipment may increase the incidence of allergic contact dermatitis. Students practising certain sports may have "professional" allergic contact dermatitis to additives used in the production of rubber.