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91.
García-Sellés FJ Díaz-Perales A Sánchez-Monge R Alcántara M Lombardero M Barber D Salcedo G Fernández-Rivas M 《International archives of allergy and immunology》2002,128(2):115-122
BACKGROUND: Lipid transfer proteins (LTPs) are major allergens of Rosaceae fruits in the Mediterranean area. IgE-cross-reactivity has been demonstrated in vitro among LTPs from peach, apple, chestnut and Artemisia pollen. The aim of this study was to evaluate the reactivity to LTPs from peach, apple, chestnut and Artemisia pollen by means of skin prick tests (SPTs). METHODS: Forty-seven patients allergic to peach (peach group), 20 patients sensitized to Artemisia pollen with no food allergies (Artemisia group), and 12 control subjects were skin tested with fresh peach, as well as with whole extracts and purified LTPs of peach, apple, chestnut and Artemisia pollen. RESULTS: The rates of positive SPTs for peach, apple, chestnut and Artemisia LTPs were, respectively, 91, 77, 23, and 36% in the peach group, and 30, 5, 15 and 40% in the Artemisia group. No response was observed in the control subjects. SPTs with peach LTP strongly correlated with SPTs conducted with fresh peach. In the peach group, the most frequent pattern of reactivity to LTPs was the combination peach-apple (45%), followed by peach-apple-Artemisia-chestnut (21%). Significant correlations were found between peach and apple LTPs, and between Artemisia and chestnut LTPs. Positive SPTs to chestnut LTP were only observed in patients with positive SPTs to Artemisia LTP. All the patients with positive case histories to chestnut reacted to chestnut LTP. CONCLUSIONS: LTPs are plant panallergens with different patterns of cross-reactivity. They are major allergens of Rosaceae fruits and seem to be involved in allergic reactions to unrelated foodstuffs such as chestnut, probably through sensitization to the cross-reactive Artemisia LTP. Rosaceae LTPs could be useful tools for in vivo diagnosis of Rosaceae fruit allergy. 相似文献
92.
Brochetta C Perrotta MG Jeromin A Romano M Vita F Soranzo MR Borelli V Roder J Zabucchi G 《Inflammation》2003,27(6):361-372
Secretion in neutrophils is thought to be regulated in different ways for the different granule types. Specific granules are endowed with proteins which are related to docking and fusion events and are absent on azurophilic granules. Furthermore, even if secretion of content from all neutrophil granules is a Ca(2+)-dependent process, a higher concentration of cytosolic calcium is required for azurophilic than for specific granule secretion. In this paper we show that human neutrophils and promyelocitic cells express neuronal calcium sensor-1 (NCS-1), a calcium binding protein involved in exocytosis in various cell types. Both mRNA and protein were found in mature cells and precursors. NCS-1 is shown to be mainly associated with azurophilic granules and, therefore could play an instrumental role in the calcium-dependent secretion of azurophilic granules. 相似文献
93.
Antonella Gambale Roberta Russo Immacolata Andolfo Lucia Quaglietta Gianluca De Rosa Valentina Contestabile Lucia De Martino Rita Genesio Piero Pignataro Sabrina Giglio Mario Capasso Rosanna Parasole Barbara Pasini Achille Iolascon 《Clinical genetics》2019,96(4):359-365
Cancer predisposition syndromes (CPS) result from germline pathogenic variants, and they are increasingly recognized in the etiology of many pediatric cancers. Herein, we report the genetic/genomic analysis of 40 pediatric patients enrolled from 2016 to 2018. Our diagnostic workflow was successful in 50% of screened cases. Overall, the proportion of CPS in our case series is 10.9% (20/184) of enrolled patients. Interestingly, 12.5% of patients achieved a conclusive diagnosis through the analysis of chromosomal imbalance. Indeed, we observed germline microdeletions/duplications of regions encompassing cancer-related genes in 50% of patients undergoing array-CGH: EIF3H duplication in a patient with infantile desmoplastic astrocytoma and low-grade Glioma; SLFN11 deletion, SOX4 duplication, and PARK2 partial deletion in three neuroblastoma patients; a PTPRD partial deletion in a child diagnosed with glioblastoma multiforme. Finally, we identified two cases due to DICER1 germline mutations. 相似文献
94.
Hepatocyte growth factor (HGF), a stimulator of angiogenesis and cell migration, regulates the growth of a wide variety of
cells by binding to its high-affinity receptor met and is involved in the growth and aggressiveness of several tumors. In
this study we investigated the expression of HGF and met in normal endocrine cells and related neoplasms of the gut and pancreas
to verify their possible role in tumor pathogenesis, growth, and aggressiveness. Normal tissues and 60 different endocrine
tumors were immunostained using specific antibodies directed against HGF, met, and various hormones. HGF immunoreactivity
(IR) was found in antroduodenal G cells, rectal enterochromaffin (EC) cells, and pancreatic A and B cells, whereas met IR
was detected in antral EC and G cells, and in pancreatic B cells; 46 of 60 tumors examined were positive for HGF, and they
were mainly represented by ECL-, EC-, and L-cell neoplasms. met IR was identified in 50/60 tumors of various phenotypes. HGF
and met coexpression was found in 42/60 cases, most of which were represented by EC-cell tumors. HGF/met coexpression was
significantly more frequent in ileolonic EC-cell tumors, which in the majority of cases were malignant, than in appendiceal
EC-cell tumors, which were all benign. Our results demonstrated, for the first time, that HGF and met are specifically distributed
in normal gut and pancreatic endocrine cells and, in addition, suggest that HGF and met may be implicated as autocrine/paracrine
factors regulating the growth of gastroenteropancreatic endocrine tumors, mainly of ileocolonic EC-cell carcinoids. 相似文献
95.
96.
Vancheri C Gili E Failla M Mastruzzo C Salinaro ET Lofurno D Pistorio MP La Rosa C Caruso M Crimi N 《The Journal of allergy and clinical immunology》2005,116(6):1242-1248
BACKGROUND: The identification of factors mediating the transition of lung fibroblasts into myofibroblasts is considered fundamental in the comprehension of abnormal reparative processes. Bradykinin, a mediator known for its proinflammatory action, is able to induce cytokine production and contractility in fibroblast cultures. OBJECTIVES: In this study the ability of bradykinin to drive fibroblast into a myofibroblast phenotype at the cellular and molecular level was evaluated. METHODS: alpha-Smooth muscle actin (alpha-SMA) expression and TGF-beta in bradykinin stimulated fibroblasts were tested by means of flow cytometry, Western blot, and RT-PCR. Cell proliferation and collagen production were evaluated by the colorimetric methylthiazol tetrazolium assay and sirius red assay, respectively. Which bradykinin receptor mediates the expression of alpha-SMA was evaluated using selective B1 and B2 blocking agents. Furthermore, the effect of bradykinin on extracellular signal-regulated kinase 1/2 phosphorylation was explored. RESULTS: Bradykinin caused in lung fibroblasts a significant increase in alpha-SMA at the cellular and molecular level. The B2 receptor was held responsible for this effect because a specific receptor antagonist had entirely blocked this effect. Bradykinin was able to induce fibroblast proliferation and collagen production. Bradykinin significantly activated mitogen-activated protein kinase pathway by phosphorylating extracellular signal-regulated kinase 1/2, whereas PD98059, a specific inhibitor, was able to block myofibroblast induction. Although bradykinin induced an increase of TGF-beta on fibroblasts, the blockage of this cytokine did not alter alpha-SMA expression. CONCLUSION: The data support the hypothesis that bradykinin may be involved in bronchial remodeling and lung fibrosis beyond its well recognized proinflammatory activity, also suggesting a new potential therapeutic strategy to control altered reparatory processes. 相似文献
97.
A MicroRNA signature associated with prognosis and progression in chronic lymphocytic leukemia 总被引:2,自引:0,他引:2
98.
de la Rosa G Longo N Rodríguez-Fernández JL Puig-Kroger A Pineda A Corbí AL Sánchez-Mateos P 《Journal of leukocyte biology》2003,73(5):639-649
Distinct subsets of dendritic cells (DCs) are present in blood, probably "en route" to different tissues. We have investigated the chemokines and adhesion molecules involved in the migration of myeloid (CD11c(+)) and plasmacytoid (CD123(+)) human peripheral blood DCs across vascular endothelium. Among blood DCs, the CD11c(+) subset vigorously migrated across endothelium in the absence of any chemotactic stimuli, whereas spontaneous migration of CD123(+) DCs was limited. In bare cell migration assays, myeloid DCs responded with great potency to several inflammatory and homeostatic chemokines, whereas plasmacytoid DCs responded poorly to all chemokines tested. In contrast, the presence of endothelium greatly favored transmigration of plasmacytoid DCs in response to CXCL12 (stromal cell-derived factor-1) and CCL5 (regulated on activation, normal T expressed and secreted). Myeloid DCs exhibited a very potent transendothelial migration in response to CXCL12, CCL5, and CCL2 (monocyte chemoattractant protein-1). Furthermore, we explored whether blood DCs acutely switch their pattern of migration to the lymph node-derived chemokine CCL21 (secondary lymphoid-tissue chemokine) in response to microbial stimuli [viral double-stranded (ds)RNA or bacterial CpG-DNA]. A synthetic dsRNA rapidly enhanced the response of CD11c(+) DCs to CCL21, whereas a longer stimulation with CpG-DNA was needed to trigger CD123(+) DCs responsive to CCL21. Use of blocking monoclonal antibodies to adhesion molecules revealed that both DC subsets used platelet endothelial cell adhesion molecule-1 to move across activated endothelium. CD123(+) DCs required beta(2) and beta(1) integrins to transmigrate, whereas CD11c(+) DCs may use integrin-independent mechanisms to migrate across activated endothelium. 相似文献
99.
Salazar-González RM Maldonado-Bernal C Ramírez-Cruz NE Rios-Sarabia N Beltrán-Nava J Castañón-González J Castillo-Torres N Palma-Aguirre JA Carrera-Camargo M López-Macías C Isibasi A 《Immunology letters》2004,93(2-3):115-122
Typhoid fever remains a serious public health problem. We have developed a vaccine from Salmonella enterica serovar typhi (S. typhi) outer-membrane proteins (OMPs) known as porins. A single subcutaneous dose of 10 microg of porins induced a five-fold (P = 0.05) seroconversion index consisting of IgM and IgG at 7 and 15 days after vaccination as well as the production of IgG1 and IgG2 isotypes. The porins-based vaccine induced a two-fold increase (P = 0.05) in bactericidal titres in volunteers, whom also developed a T-cell response characterized by the production of interferon-gamma (INF-gamma). Side effects after vaccination were mild and transient. The data showed that our S. typhi porins-based candidate vaccine is safe and immunogenic in healthy humans. 相似文献
100.
Rodrigues FC Kawasaki-Oyama RS Fo JF Ukuyama EE Antonio JR Bozola AR Romeiro JG Rahal P Tajara EH 《Cancer Genetics and Cytogenetics》2003,142(2):92-98
The CDKN1A (TP21) gene encodes a 21-kD protein that is a critical downstream mediator of wild-type TP53 and an important regulator of the cell cycle. Failure in the function of this gene would be expected to result in abnormal cell proliferation and transformation. Tumor-associated mutations of the coding region of the TP21 are rare. On the other hand, some TP21 polymorphisms have been identified and characterized by single base substitutions. In the present study, we investigated the potential role of TP21 gene polymorphisms in skin, head, and neck tumorigenesis. A total of 261 samples were examined by polymerase chain reaction single-strand conformational analysis, and one mutation at codon 31 and four polymorphisms in exons 2 (codon 55) and 3 [nucleotide (nt)590] and in promoter region (nt2298) were identified. In conclusion, this investigation confirmed the rarity of mutations in this gene, arguing against a role for TP21 mutations in skin, head, and neck cancers. Also, our results show significant differences in nt2298 allele frequencies between normal individuals and skin malignant tumors (P < 0.05). The results suggest that this polymorphism affects TP21 transactivator binding and may be important during the pathogenesis of skin cancer. 相似文献