107 research outputs found

    Collective dynamics in crystalline polymorphs of ZnCl2_{2}: potential modelling and inelastic neutron scattering study

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    We report a phonon density of states measurement of α\alpha-ZnCl2_{2} using the coherent inelastic neutron scattering technique and a lattice dynamical calculation in four crystalline phases of ZnCl2_{2} using a transferable interatomic potential. The model calculations agree reasonably well with the available experimental data on the structures, specific heat, Raman frequencies and their pressure variation in various crystalline phases. The calculated results have been able to provide a fair description of the vibrational as well as the thermodynamic properties of ZnCl2_{2} in all its four phases.Comment: Accepted in J. Phys.: Condens. Matte

    Update about Oralair® as a treatment for grass pollen allergic rhinitis

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    Sublingual immunotherapy (SLIT) is a well-tolerated, safe, and effective approach to treating allergic rhinitis (AR). Oralair (R) is a five-grass pollen SLIT tablet containing natural pollen allergens from five of the major grass species responsible for seasonal AR due to grass pollen allergy. Recommended use is in a pre-coseasonal regimen, starting daily treatment approximately 4 months before the start of the pollen season, with treatment then continued daily throughout the season; treatment should continue for 3-5 y. Clinical efficacy and safety of Oralair (R) in patients with grass pollen-induced AR has been demonstrated in a comprehensive clinical development program of randomized controlled trials. Effectiveness has been substantiated in subsequent observational studies with sustained efficacy following treatment cessation and a favorable level of adherence, quality of life, benefit, and satisfaction for the patients. Supportive evidence for a benefit in reducing the risk or delaying the development of allergic asthma is emerging

    Ligelizumab for Chronic Spontaneous Urticaria

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    Background: In the majority of patients with chronic spontaneous urticaria, most currently available therapies do not result in complete symptom control. Ligelizumab is a next-generation high-affinity humanized monoclonal anti-IgE antibody. Data are limited regarding the dose–response relationship of ligelizumab and the efficacy and safety of ligelizumab as compared with omalizumab and placebo in patients who have moderate-to-severe chronic spontaneous urticaria that is inadequately controlled with H1-antihistamines at approved or increased doses, alone or in combination with H2-antihistamines or leukotriene-receptor antagonists. Methods: In a phase 2b dose-finding trial, we randomly assigned patients to receive ligelizumab at a dose of 24 mg, 72 mg, or 240 mg, omalizumab at a dose of 300 mg, or placebo, administered subcutaneously every 4 weeks for a period of 20 weeks, or a single 120-mg dose of ligelizumab. Disease symptoms of hives, itch, and angioedema were monitored by means of weekly activity scores. The main objective was to determine a dose–response relationship for the complete control of hives (indicated by a weekly hives-severity score of 0, on a scale from 0 to 21, with higher scores indicating greater severity); the primary end point of this response was assessed at week 12. Complete symptom control was indicated by a weekly urticaria activity score of 0 (on a scale from 0 to 42, with higher scores indicating greater severity). Safety was analyzed throughout the trial. Results: A total of 382 patients underwent randomization. At week 12, a total of 30%, 51%, and 42% of the patients treated with 24 mg, 72 mg, and 240 mg, respectively, of ligelizumab had complete control of hives, as compared with 26% of the patients in the omalizumab group and no patients in the placebo group. A dose–response relationship was established. At week 12, a total of 30%, 44%, and 40% of the patients treated with 24 mg, 72 mg, and 240 mg, respectively, of ligelizumab had complete control of symptoms, as compared with 26% of the patients in the omalizumab group and no patients in the placebo group. In this small and short trial, no safety concerns regarding ligelizumab or omalizumab emerged. Conclusions: A higher percentage of patients had complete control of symptoms of chronic spontaneous urticaria with ligelizumab therapy of 72 mg or 240 mg than with omalizumab or placebo. (Funded by Novartis Pharma; ClinicalTrials.gov number, NCT02477332. opens in new tab.

    Standardization of double blind placebo controlled food challenge with soy within a multicentre trial

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    Background: Multicentre trials investigating food allergies by double blind placebo controlled food challenges (DBPCFC) need standardized procedures, challenge meals and evaluation criteria. We aimed at developing a standardized approach for identifying patients with birch related soy allergy by means of DBPCFC to soy, including determination of threshold levels, in a multicentre setting. Methods: Microbiologically stable soy challenge meals were composed of protein isolate with consistent Gly m 4 levels. Patients sensitized to main birch allergen Bet v 1 and concomitant sensitization to its soy homologue Gly m 4 underwent DBPCFC. Outcome was defined according to presence and/or absence of ten objective signs and intensity of eight subjective symptoms as measured by visual analogue scale (VAS). Results: 138 adult subjects (63.8% female, mean age 38 years) underwent DBPCFC. Challenge meals and defined evaluation criteria showed good applicability in all centres involved. 45.7% presented with objective signs and 65.2% with subjective symptoms at soy challenge. Placebo challenge meals elicited non-cardiovascular objective signs in 11.6%. In 82 (59.4%) subjects DBPCFC was judged as positive. 70.7% of DPBCFC+ showed objective signs and 85.4% subjective symptoms at soy challenge. Subjective symptoms to soy challenge meal in DBPCFC+ subjects started at significantly lower dose levels than objective signs (p < 0.001). Median cumulative eliciting doses for first objective signs in DBPCFC+ subjects were 4.7 g [0.7–24.7] and 0.7 g [0.2–4.7] total soy protein for first subjective symptoms (p = 0.01). Conclusions: We present the hitherto largest group of adults with Bet v 1 and Gly m 4 sensitization being investigated by DBPCFC. In this type of food allergy evaluation of DBPCFC outcome should not only include monitoring of objective signs but also scoring of subjective symptoms. Our data may contribute to standardize DBPCFC in pollen-related food allergy in multicentre settings. Trial registration EudraCT: 2009-011737-27

    Reduction of Cross-Reactive Carbohydrate Determinants in Plant Foodstuff: Elucidation of Clinical Relevance and Implications for Allergy Diagnosis

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    Background: A longstanding debate in allergy is whether or not specific immunoglobulin-E antibodies (sIgE), recognizing cross-reactive carbohydrate determinants (CCD), are able to elicit clinical symptoms. In pollen and food allergy, $20% of patients display in-vitro CCD reactivity based on presence of a1,3-fucose and/or b1,2-xylose residues on N-glycans of plant (xylose/fucose) and insect (fucose) glycoproteins. Because the allergenicity of tomato glycoallergen Lyc e 2 was ascribed to N-glycan chains alone, this study aimed at evaluating clinical relevance of CCD-reduced foodstuff in patients with carbohydrate-specific IgE (CCD-sIgE). Methodology/Principal Findings: Tomato and/or potato plants with stable reduction of Lyc e 2 (tomato) or CCD formation in general were obtained via RNA interference, and gene-silencing was confirmed by immunoblot analyses. Two different CCD-positive patient groups were compared: one with tomato and/or potato food allergy and another with hymenopteravenom allergy (the latter to distinguish between CCD- and peptide-specific reactions in the food-allergic group). Nonallergic and CCD-negative food-allergic patients served as controls for immunoblot, basophil activation, and ImmunoCAP analyses. Basophil activation tests (BAT) revealed that Lyc e 2 is no key player among other tomato (glyco)allergens. CCDpositive patients showed decreased (re)activity with CCD-reduced foodstuff, most obvious in the hymenoptera venomallergic but less in the food-allergic group, suggesting that in-vivo reactivity is primarily based on peptide- and not CCDsIgE. Peptide epitopes remained unaffected in CCD-reduced plants, because CCD-negative patient sera showed reactivity similar to wild-type. In-house-made ImmunoCAPs, applied to investigate feasibility in routine diagnosis, confirmed BAT results at the sIgE level. Conclusions/Significance: CCD-positive hymenoptera venom-allergic patients (control group) showed basophil activation despite no allergic symptoms towards tomato and potato. Therefore, this proof-of-principle study demonstrates feasibility of CCD-reduced foodstuff to minimize ‘false-positive results’ in routine serum tests. Despite confirming low clinical relevance of CCD antibodies, we identified one patient with ambiguous in-vitro results, indicating need for further component-resolved diagnosis

    Allergen-specific immunotherapy provides immediate, long-term and preventive clinical effects in children and adults: the effects of immunotherapy can be categorised by level of benefit -the centenary of allergen specific subcutaneous immunotherapy

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    Allergen Specific Immunotherapy (SIT) for respiratory allergic diseases is able to significantly improve symptoms as well as reduce the need for symptomatic medication, but SIT also has the capacity for long-term clinical effects and plays a protective role against the development of further allergies and symptoms. The treatment acts on basic immunological mechanisms, and has the potential to change the pathological allergic immune response. In this paper we discuss some of the most important achievements in the documentation of the benefits of immunotherapy, over the last 2 decades, which have marked a period of extensive research on the clinical effects and immunological background of the mechanisms involved. The outcome of immunotherapy is described as different levels of benefit from early reduction in symptoms over progressive clinical effects during treatment to long-term effects after discontinuation of the treatment and prevention of asthma. The efficacy of SIT increases the longer it is continued and immunological changes lead to potential long-term benefits. SIT alone and not the symptomatic treatment nor other avoidance measures has so far been documented as the therapy with long-term or preventive potential. The allergic condition is driven by a subset of T-helper lymphocytes (Th2), which are characterised by the production of cytokines like IL-4, and IL-5. Immunological changes following SIT lead to potential curative effects. One mechanism whereby immunotherapy suppresses the allergic response is through increased production of IgG4 antibodies. Induction of specific IgG4 is able to influence the allergic response in different ways and is related to immunological effector mechanisms, also responsible for the reduced late phase hyperreactivity and ongoing allergic inflammation. SIT is the only treatment which interferes with the basic pathophysiological mechanisms of the allergic disease, thereby creating the potential for changes in the long-term prognosis of respiratory allergy. SIT should not only be recognised as first-line therapeutic treatment for allergic rhinoconjunctivitis but also as secondary preventive treatment for respiratory allergic diseases

    Anaphylaxis in Elderly Patients-Data From the European Anaphylaxis Registry

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    Background: Elicitors and symptoms of anaphylaxis are age dependent. However, little is known about typical features of anaphylaxis in patients aged 65 years or more. Methods: The data from the Network for Online Registration of Anaphylaxis (NORA) considering patients aged ≥65 (elderly) in comparison to data from adults (18–64 years) regarding elicitors, symptoms, comorbidities, and treatment measures were analyzed. Results: We identified 1,123 elderly anaphylactic patients. Insect venoms were the most frequent elicitor in this group (p < 0.001), followed by drugs like analgesics and antibiotics. Food allergens elicited less frequently anaphylaxis (p < 0.001). Skin symptoms occurred less frequently in elderly patients (77%, p < 0.001). The clinical symptoms were more severe in the elderly (51% experiencing grade III/IV reactions), in particular when skin symptoms (p < 0.001) were absent. Most strikingly, a loss of consciousness (33%, p < 0.001) and preexisting cardiovascular comorbidity (59%, p < 0.001) were more prevalent in the elderly. Finally, adrenaline was used in 30% of the elderly (vs. 26% in the comparator group, p < 0.001) and hospitalization was more often required (60 vs. 50%, p < 0.001). Discussion and Conclusion: Anaphylaxis in the elderly is often caused by insect venoms and drugs. These patients suffer more often from cardiovascular symptoms, receive more frequently adrenaline and require more often hospitalization. The data indicate that anaphylaxis in the elderly tends to be more frequently life threatening and patients require intensified medical intervention. The data support the need to recognize anaphylaxis in this patient group, which is prone to be at a higher risk for a fatal outcome

    Acute mountain sickness.

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    Acute mountain sickness (AMS) is a clinical syndrome occurring in otherwise healthy normal individuals who ascend rapidly to high altitude. Symptoms develop over a period ofa few hours or days. The usual symptoms include headache, anorexia, nausea, vomiting, lethargy, unsteadiness of gait, undue dyspnoea on moderate exertion and interrupted sleep. AMS is unrelated to physical fitness, sex or age except that young children over two years of age are unduly susceptible. One of the striking features ofAMS is the wide variation in individual susceptibility which is to some extent consistent. Some subjects never experience symptoms at any altitude while others have repeated attacks on ascending to quite modest altitudes. Rapid ascent to altitudes of 2500 to 3000m will produce symptoms in some subjects while after ascent over 23 days to 5000m most subjects will be affected, some to a marked degree. In general, the more rapid the ascent, the higher the altitude reached and the greater the physical exertion involved, the more severe AMS will be. Ifthe subjects stay at the altitude reached there is a tendency for acclimatization to occur and symptoms to remit over 1-7 days
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