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61.
Ioana Maris Sabine Dölle-Bierke Jean-Marie Renaudin Lars Lange Alice Koehli Thomas Spindler Jonathan Hourihane Kathrin Scherer Katja Nemat C. Kemen Irena Neustädter Christian Vogelberg Thomas Reese Ismail Yildiz Zsolt Szepfalusi Hagen Ott Helen Straube Nikolaos G. Papadopoulos Susanne Hämmerling Ute Staden Michael Polz Tihomir Mustakov Ewa Cichocka-Jarosz Renata Cocco Alessandro Giovanni Fiocchi Montserrat Fernandez-Rivas Margitta Worm Network for Online Registration of Anaphylaxis 《Allergy》2021,76(5):1517-1527
Background
Peanut allergy has a rising prevalence in high-income countries, affecting 0.5%–1.4% of children. This study aimed to better understand peanut anaphylaxis in comparison to anaphylaxis to other food triggers in European children and adolescents.Methods
Data was sourced from the European Anaphylaxis Registry via an online questionnaire, after in-depth review of food-induced anaphylaxis cases in a tertiary paediatric allergy centre.Results
3514 cases of food anaphylaxis were reported between July 2007 - March 2018, 56% in patients younger than 18 years. Peanut anaphylaxis was recorded in 459 children and adolescents (85% of all peanut anaphylaxis cases). Previous reactions (42% vs. 38%; p = .001), asthma comorbidity (47% vs. 35%; p < .001), relevant cofactors (29% vs. 22%; p = .004) and biphasic reactions (10% vs. 4%; p = .001) were more commonly reported in peanut anaphylaxis. Most cases were labelled as severe anaphylaxis (Ring&Messmer grade III 65% vs. 56% and grade IV 1.1% vs. 0.9%; p = .001). Self-administration of intramuscular adrenaline was low (17% vs. 15%), professional adrenaline administration was higher in non-peanut food anaphylaxis (34% vs. 26%; p = .003). Hospitalization was higher for peanut anaphylaxis (67% vs. 54%; p = .004).Conclusions
The European Anaphylaxis Registry data confirmed peanut as one of the major causes of severe, potentially life-threatening allergic reactions in European children, with some characteristic features e.g., presence of asthma comorbidity and increased rate of biphasic reactions. Usage of intramuscular adrenaline as first-line treatment is low and needs to be improved. The Registry, designed as the largest database on anaphylaxis, allows continuous assessment of this condition.62.
Stefan Carrel Alessandro Moretta Giuseppe Pantaleo Giuseppe Tambussi Patrick Isler Bice Perussia Jean-Charles Cerottini 《European journal of immunology》1988,18(3):333-339
There is experimental evidence that the CD4 molecule participates in the antigen-driven activation of T cells expressing this surface glycoprotein. Whether CD4, a member of the immunoglobulin supergene family, acts as a ligand-binding molecule and/or is directly involved in the activation pathway has yet to be established. In this study, we show that human CD4+ lymphocytes can be activated by exposure to the anti-CD4 monoclonal antibody (mAb) B66. Normal peripheral blood CD4+ cells were induced to proliferate and to synthesize interleukin 2 (IL2) by the antibody. The specificity of the antibody stimulatory activity was tested by using IL2-producing clones bearing either CD4 or CD8 on their surface. IL2 production was induced by mAb B66 in CD4+, but not CD8+, clones, whereas both types of clones responded to stimulation by the anti-CD3 mAb Leu-4. Despite its unique stimulatory activity, mAb B66 shared with other anti-CD4 antibodies the ability to inhibit the specific cytolytic activity of CD4+ effector cells. These results clearly indicate that cross-linking of surface CD4 molecules with appropriate antibodies can fully activate CD4+ lymphocytes. Whether the natural ligand for CD4 can trigger this activation pathway remains to be defined. 相似文献
63.
Alessandro Michienzi Fernanda G De Angelis Irene Bozzoni John J Rossi 《AIDS research and therapy》2006,3(1):13-9
The Rev protein of the human immunodeficiency virus (HIV) facilitates the nuclear export of intron containing viral mRNAs
allowing formation of infectious virions. Rev traffics through the nucleolus and shuttles between the nucleus and cytoplasm.
Rev multimerization and interaction with the export protein CRM1 takes place in the nucleolus. To test the importance of Rev
nucleolar trafficking in the HIV-1 replication cycle, we created a nucleolar localizing Rev Response Element (RRE) decoy and
tested this for its anti-HIV activity. The RRE decoy provided marked inhibition of HIV-1 replication in both the CEM T-cell
line and in primary CD34+ derived monocytes. These results demonstrate that titration of Rev in the nucleolus impairs HIV-1
replication and supports a functional role for Rev trafficking in this sub-cellular compartment. 相似文献
64.
65.
Alessandro Finazzi-Agrò Giovanni Floris Maria Benedetta Fadda Carlo Crifò 《Inflammation research》1979,9(3):244-247
Various drugs were tested as inhibitors of diamine oxidase on the basis of chemical relationships to the enzyme substrates.It was found that serotonine tryptamine and phenformin are good competitive inhibitors while cimetidine and pheniprazine are non-competitive inhibitors. Other antihistaminic drugs like promethazine are less powerful inhibitors. 相似文献
66.
Down-regulation of nitric oxide synthase-2 and cyclooxygenase-2 pathways by p53 in squamous cell carcinoma 总被引:7,自引:0,他引:7 下载免费PDF全文
Gallo O Schiavone N Papucci L Sardi I Magnelli L Franchi A Masini E Capaccioli S 《The American journal of pathology》2003,163(2):723-732
The goal of this study was to analyze the correlation between inducible nitric oxide synthase (iNOS) and COX-2 activities and p53 gene status in head and neck squamous cell carcinomas (HNSCCs) in vivo and in vitro. In a series of 43 HNSCCs we observed an up-regulation of both iNOS and COX-2 pathways in tumor tissues and both activities were correlated each other (rs = 0.612 and P = 0.0002). We also found that p53-mutated HNSCCs (25 cases, 58.1%) showed higher levels of iNOS activity and cGMP in comparison with wild-type p53 tumors (18 cases, 41.9%) (P = 0.0005 and P = 0.01), as well as higher iNOS immunohistochemical expression (P = 0.03). Analogously, higher PgE2 levels were documented in p53-mutated HNSCCs when compared with wild-type p53 tumors (P = 0.015) and COX-2 protein expression was higher in p53-mutated HNSCCs (P = 0.007). A431 cancer cells expressing a p53 temperature-sensitive mutant showed an approximately 1.9- and 2.6-fold decrease in spontaneous NO(2-)/NO(3-) and PgE2 synthesis at permissive temperature, respectively, when compared with the same cells at nonpermissive temperature (P 相似文献
67.
68.
Human natural killer (NK) cells are effectors of innate immunity, capable of killing transformed or virus-infected cells and producing pro-inflammatory cytokines. Soluble molecules of HLA-I (sHLA-I), which are significantly increased in the serum of patients affected by auto-immune or infectious or neoplastic diseases, induce NK cell apoptosis interacting with its ligands, such as CD8 or the activating isoforms of members of inhibitory superfamily receptors (IRS). This cell death is accompanied by the release of large amounts of interferon-gamma. NK cells can kill autologous target cells, including antigen presenting cells or infected or tumor cells, by engaging the natural cytotoxicity receptors (NCR) NKp30, or NKp44 and NKp46. Again, the binding between NCR on NK cells and their putative ligands on targets leads to NK cell apoptosis. FasL produced and secreted by NK cells is responsible for the NK cell apoptosis induced by either HLA-I receptors or NCR. Interestingly, cyclosporin A (CsA) blocks NK cell death consequent to interaction with target cells or with sHLA-I, without affecting the activation of cytolysis. This would indicate that CsA can maintain NK cell-dependent innate immunity by prolonging NK cell survival in an hostile environment in the presence of sHLA-I or target cells. 相似文献
69.
Domenico Schiavino Eleonora Nucera Emanuela Pollastrini Tiziana De Pasquale Alessandro Buonomo Francesco Bartolozzi Carla Lombardo Chiara Roncallo Giampiero Patriarca 《Annals of allergy, asthma & immunology》2004,92(4):409-413
BACKGROUND: Hymenoptera venom hypersensitivity is an epidemiologically important problem. The only effective treatment in the management of venom-allergic patients with a history of generalized reactions to insect sting is specific immunotherapy. OBJECTIVE: To demonstrate safety and effectiveness of a modified ultrarush desensitization protocol in venom-allergic patients. METHODS: Fifty-seven patients with Hymenoptera venom allergy underwent a specific 1-day ultrarush desensitization by the subcutaneous route, reaching the cumulative dose of 101.1 microg in 2.5 hours. The maintenance dose (100 microg) was administered after 15 days and thereafter once a month. Patients were followed up for a year. Antihistamines were withheld for 15 days before and during desensitization to not underestimate the incidence of adverse effects. RESULTS: All patients but I completed the ultrarush desensitization. (This patient discontinued the treatment because of a hypertensive crisis not related to the desensitization.) The treatment caused a rapid variation of immunological parameters (IgE, IgG4) since the 15th day. After the desensitization, skin prick test results became negative in 15 patients (27%, decrease of 3.5 log), whereas they decreased in 14 patients (25%, decrease of 1 log). Sixty-four percent showed no adverse effects. Only 7% had a mild systemic reaction. CONCLUSIONS: Ultrarush desensitization is an effective and safe therapy in the management of patients with Hymenoptera venom allergy. In fact, it provides a faster tolerance, without significant differences regarding incidence of severe adverse effects, compared with traditional and rush protocols. It can be adopted for all patients, even children and teenagers. 相似文献
70.
Pietro Maria Donisi Nadia Di Lorenzo Manuela Riccardi Alessandro Paparella Claudia Sarpellon Simona Zupo Giovanni Bertoldero Claudia Minotto Vincenzo Stracca-Pansa 《Diagnostic molecular pathology》2006,15(4):206-215
We analyzed individual VH gene rearrangements in 55 consecutive B-chronic lymphocytic leukemia (B-CLL) patients collected from a northeastern region of Italy, stressing the possible differences related to geographic characteristics of the cohorts studied. Considering the percentage of somatic mutations present in the VH gene sequences and using the 98% cut-off value, 38 of the 55 B-CLL (69%) patients displayed somatic hypermutations and 17 (31%) had a germline configuration. Our results confirm and extend the observations of a bias in the use of certain VH, DH, and JH genes among B-CLL cells. The most frequently used VH genes were VH1-69 (12.7%) with VH3-23 (12.7%) and VH4-34 (10.9%). Collectively these genes accounted for 36.3% of the cases. In the mutated cases, the range of mutations varied from 2% to 15%, with a median of 6.5%. VH1-69 (7 cases, all unmutated) carried few mutations as opposed to VH3-23 (7 cases, 5 of which mutated), VH4-34 (6 cases, all mutated), and VH3-30 (5 cases, all mutated), which show a high load of mutations. D3 family genes were found frequently (38.1%) followed by D2 (27.2%) and D6 (18.1%). The individual D segment most frequently used was D3-3, which was present in 16.3% of cases. There was predominance of the JH4 gene (49%) followed by JH6 (40%). Analysis of the distribution of replacement and silent mutations in the mutated sequences using the method of Lossos showed in 39.4% of cases evidence of antigen selection in the framework region and/or complementary determining regions. In comparison with a recent study on B-CLL patients from the Mediterranean area, the VH4-34 gene was significantly overused in the mutated group at a percentage double that of the Italian cohort reported in this study (10.9% vs. 5%), but at a frequency similar to the entire Mediterranean region (10.7%). We also found an over-representation of VH1-69 usage in the germline group, at a frequency (12.7%) higher than previously described by the same authors (Italian 8%, Mediterranean 10.7%). On the contrary, VH3-07 and VH3-49 were not much used in our study (5.4% and 1.8%, respectively) compared with the Italian group (8% and 5.1%). In our study, VH3-23 gene segment was frequently expressed, at frequency as high as that of VH1-69, a finding in keeping with reported B-CLL Italian data, but higher than the entire series of the Mediterranean area (12.7% vs. 9.2%); VH3-21 gene, frequently expressed in northern European CLL but rarely in the Mediterranean area, was completely absent. This biased usage of VH family genes may reflect a geographic leukemic repertoire, perhaps owing to a peculiar genetic background, depending on variations in germline composition of the IgVH locus or to the effect of a potential environmental element less frequently encountered in different regions. 相似文献