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1.
IgE mediates allergic reactions by binding to the high-affinity receptor, Fc epsilonR1, on mast cells and basophils at mucosal surfaces; then cross-linking of the receptor by multivalent antigen triggers the allergic response. We demonstrate here that B cells in the nasal mucosa of patients with hay fever express IgE. The results also suggest that allergen-induced heavy-chain switching to IgE occurs locally within the nasal mucosa. Local IgE synthesis may explain why some 'atopic' patients develop rhinitis whereas others have either no clinical manifestations or develop atopic disease elsewhere.  相似文献   

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Food allergy is a common condition among infants. The reactions are usually to milk, egg and peanut products. They frequently improve with time. It is important for the practitioner to recognise the occurrence of these reactions and to advise parents of their significance.  相似文献   

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We examined the genomic status of the p16INK4A (inhibitor of cyclin-dependent kinase 4 A) and cyclin-dependent kinase 4 (CDK4) genes in 62 human hepatocellular carcinomas (HCCs), 5 cholangiocellular carcinomas and 6 cell lines derived from human liver cancers. Although no samples showed the homozygous deletion of the p16INK4A gene, we detected intragenic mutations of the p16INK4A gene in 3 HCCs and one HCC cell line, which led to an amino-acid substitution or a frameshift. In 2 HCC samples with mis-sense mutations of the p16INK4A gene, loss of heterozygosity on 9p22 was also detected, suggesting that the loss of function of p16 was induced during hepatocarcinogenesis. On the other hand, amplification or rearrangement of the CDK4 gene was not detected in any samples examined in this study. These results indicated that the mutations or deletions of the p16INK4A gene are not frequent, but may play a role in a sub-set of human HCC.  相似文献   

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Efficient, inexpensive, and safe methods of oxygen delivery are needed for children with severe pneumonia in developing countries. The objective of this study was to estimate the frequency of complications when nasal catheters or nasal prongs are used to delivery oxygen. Ninety-nine children between 2 weeks and 5 years of age with hypoxia were randomized to receive oxygen via nasal catheter (49 children) or nasal prongs (50 children). There was no difference in the incidence of hypoxaemic episodes or in the oxygen flow rates between the two groups. Mucus production was more of a problem in the catheter group. Nasal blockage, intolerance to the method of administration, and nursing effort were generally higher amongst the catheter group, but these differences were not significant, except for nursing effort, when all age groups were analysed together.  相似文献   

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This paper describes a release program developed in 1995 for year I hospital based GP registrars in the Rural Training Stream of the Royal Australian College of General Practitioners Training Program in South Australia. Background, objectives, content and organisation, and evaluation are described. The 1996 program that developed from this pilot is also described.  相似文献   

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BACKGROUND: Skin testing is a common diagnostic procedure in food allergy. The skin prick test is the test of first choice for investigating the immediate IgE-mediated reaction. The skin application food test (SAFT) has been developed on the basis of the mechanism of the contact urticaria syndrome (CUS). METHODS: We studied the relevance of the SAFT in children younger than 4 years with atopic dermatitis and (suspected) food allergy as compared with the prick-prick test, the radioallergosorbent test (RAST), and the oral challenge. In the skin tests, we used fresh food, in the same state as it was consumed. RESULTS: There was a good agreement between the SAFT and the prick-prick test. A moderate agreement was observed between the SAFT and the serologic test (RAST). Significantly more positive results in the RAST were observed than in the SAFT. There was very good agreement between the SAFT and the oral challenge (kappa = 0.86). CONCLUSIONS: The SAFT is a reliable and child-friendly skin test for evaluating (suspected) food allergy in children younger than 4 years with atopic dermatitis. The very good correlation with the oral challenge indicates that one may probably consider the SAFT a "skin provocation" in children younger than 4 years.  相似文献   

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BACKGROUND: It is uncertain as to what extent the development of allergic disease in childhood is predictable during early infancy. A number of environmental factors have been suspected of increasing the risk of acquiring allergy, but the evidence is conflicting. OBJECTIVE: To observe the development of atopy and allergic disease in a cohort of high-risk children so as to determine the importance of certain environmental factors and to study the relationship between early and later manifestations. METHODS: A cohort of infants, all at high risk of allergy, was followed up from birth to the age of 7 years. In half, selected at random, cow's milk protein was avoided for 4 months. Skin-prick tests were performed and serum IgE measured in infancy and at 7 years, when an AlaTOP test was also performed. RESULTS: Skin sensitivity to egg in the first year of life was strongly associated with eczema, asthma, mite sensitivity and serum IgE at the age of 7 years, when mother's atopic history was associated with AlaTOP status, father's atopic history with skin sensitivity, and male sex with both. Maternal smoking during pregnancy was associated positively with IgE at 3 months and negatively with skin sensitivity at 7 years. The development of allergy was unrelated to infant feeding method or number of older siblings. CONCLUSION: Allergic disease in childhood is to a large degree determined before birth or during infancy.  相似文献   

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Changes in the membrane potential of Saccharomyces cerevisiae were monitored by the electrochromic probe 3-(4-(2-(6-(dibutylamino)-2-naphthyl)-trans- ethenyl)pyridinium)propanesulfonate (di-4-ANEPPS) that should incorporate into the plasma membrane. The probe had suitable spectral characteristics and exhibited an electrochromic shift upon a change in membrane potential but the magnitude of the response increased with time. The presence and properties of the cell wall affected the extent of cell staining. The time dependence of the fluorescent response indicated that the probe was not incorporated solely into the plasma membrane but spread gradually into the whole cell; this was confirmed by confocal microscopy. The probe is therefore suitable for assessing membrane potential changes only over time intervals up to 30 min. Longer monitoring will require either a modified staining protocol or a derivatization of the probe molecule. As found by using the dioctyl derivative di-8-ANEPPS, extending the aliphatic chains of the di-4-ANEPPS molecule does not prevent the dye from penetrating into the cell or liposome interior and, in addition, impairs staining.  相似文献   

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40 children aged from 1 to 8 years with failure to thrive, suspected of food allergy were examined. In the small intestine biopsy, normal mucosa or atrophy of intestinal villi of various intensity were found. Eosinophilic infiltration in the submucosa was present. In children over the 3rd year of life, "prick" skin test was performed, confirming polyallergy. Total IgE level was tested in all patients but only in 25% of children was it elevated.  相似文献   

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From 274 adenoidectomized children 1-16 years of age two groups were selected: children with a history of recurrent otitis media and/or otosalpingitis (middle ear effusion) and those in which nasal obstruction was the main symptom. In all, 154 children were subjected to an allergy investigation including history, skin tests, eye tests, determination of IgE and RAST, blood eosinophils and immunoglobulins G, A and M. No increased incidence of immunoglobulin deficiency was found in either group in comparison with unselected children. A family history of atopic disease and/or otitis media was highly overrepresented, especially in the children with recurrent otitis media as the reason for the adenoidectomy. Atopic diseases had occurred in 24.4% of the children. Furthermore, in both groups there was a high incidence of positive skin and eye tests. An increased incidence of eosinophila, positive RAST tests and elevated IgE levels were also found. In all, 39.6% of the children had two or more laboratory findings characteristic of the atopic state but no significant difference was found between the two groups. Possible connections between atopic allergy and recurrent otitis media are discussed.  相似文献   

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It has been hypothesized that concentrations of exhaled nitric oxide (NO) may be related to the extent of cytokine-mediated airway inflammation. Recent findings indicate the nasal airways as an important site of NO production. Our objective was to evaluate whether children with allergic rhinitis show different nasal NO levels when compared with normal healthy subjects and the effect of topical steroids and anti-histamine therapy. We have measured the concentration of NO drawn from the nose of 21 children (5-17 years old) affected by perennial allergic rhinitis (house dust mite) out of therapy for at least 3 weeks. Thirteen children were then treated with nasal beclomethasone dipropionate (BDP) (400 micrograms daily) and eight subjects with nasal anti-histamine levocabastine (200 micrograms daily). Measurements were performed before and after 10 days of treatment. As a control group we evaluated 21 healthy children aged 5-15 years. To measure NO we used a chemiluminescence analyser. Before treatment the whole group of children with allergic rhinitis showed a mean (+/- SEM) nasal NO concentration of 267 +/- 18 ppb, significantly higher (P < 0.01) than the control group (186 +/- 15 ppb). The group of children treated with BDP showed, after 10 days of therapy, a significant (P < 0.05) decrease of nasal NO concentration (271 +/- 21 ppb vs. 212 +/- 20 ppb). Indeed, in the group treated with levocabastine, nasal NO concentrations did not present a significant difference (P not significant) compared with baseline (261 +/- 33 ppb and 252 +/- 31 ppb, respectively). These data suggest that (1) children with allergic rhinitis have higher levels of nasal NO than non-atopic controls and (2) intranasal steroid therapy significantly reduces nasal NO production in children with allergic rhinitis. We speculate that the allergic inflammatory response may influence the nasal NO levels and that NO measurements may be a useful marker of nasal inflammation.  相似文献   

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BACKGROUND: Approximately 40 to 80% of egg-allergic children outgrow egg allergy after 2 to 5 years. OBJECTIVE AND METHODS: To detail the immunologic mechanisms involved in the development of tolerance to egg proteins, the balance between interleukin 4 (IL4) and interferon-gamma (IFN-gamma) synthesis in patients with active atopic dermatitis allergic to hen egg and in those outgrowing hen egg allergy was evaluated. RESULTS: A marked increase in IL4 and a decrease in IFN-gamma synthesis by peripheral blood lymphocytes following ovalbumin (OVA) specific in vitro stimulation was observed in active atopic dermatitis. In contrast, OVA-induced IL4 synthesis in patients in remission was comparable to that in normal individuals. An intriguing finding was higher production of IFN-gamma by lymphocytes from ovalbumin-insensitive patients in remission as compared to normal individuals following antigen stimulation, although cell proliferation in OVA-stimulated lymphocytes was reduced in patients during remission. CONCLUSION: OVA antigen may be capable of inducing a population of Th1-type cells to produce cytokines such as IFN-gamma, resulting in suppression of Th2-type responses, i.e. IL4 secretion. We speculate that the changes in the balance of relevant antigen-induced cytokine synthesis seen in such patients may be causally associated with the improvement in their clinical status.  相似文献   

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牛奶过敏(cow's milk allergy)是小儿最常见的食物过敏之一,在欧美发达国家,婴儿牛奶过敏发生率约2%~7.5%.牛奶过敏的婴儿还可能对其它食物过敏,如蛋类、豆类、花生仁等,50%牛奶过敏婴儿以后可能出现对吸人性过敏原,如尘螨、花粉等过敏,同时,牛奶过敏婴儿还存在着发生哮喘、湿疹、过敏性鼻炎等特应性疾病的风险.  相似文献   

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BACKGROUND: To study the clinical and immunological data of patients affected by a soybean asthma outbreak in Tarragona, Spain. PATIENTS AND METHODS: Characteristics of previous asthma, emergency rooms records and immediate outcome of 15 patients who attended emergency room departments the epidemic day were recorded. Functional respiratory studies, skin prick tests to aeroallergens, and prick tests, specific IgE and immunoblotting to soybean extracts were performed in all patients. RESULTS: Thirteen patients were sensitized to soybean proteins. All of them were atopic (most sensitized to house dust mites) and half had started asthma symptoms after their thirties. The epidemic crisis was particularly severe in patients over 50 years, daily chronic asthma, severe obstructive pattern and/or non receiving steroids. Four patients were admitted to intensive care units. Seven patients showed asthma exacerbations (late reactions) 24 h after the beginning of the epidemic crisis. Specific IgE against a 5-6 kD and a 15.5-17 kD soybean proteins was detected in the sera of 8 patients and 10 patients, respectively. CONCLUSIONS: The outbreak affected atopic patients exposed to soybean dust. The severity of the crisis was related with the previous severity of asthma. Besides the well known 5-6 kD allergenic soybean protein, the 15.5-17 kD protein seems also to be implicated in the sensitization of most of these patients.  相似文献   

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BACKGROUND: Cetirizine is an antihistamine, largely used in the treatment of allergic rhinoconjunctivitis, which also exerts anti-allergic activity. OBJECTIVE: To evaluate cetirizine as treatment for children with rhinitis due to pollen allergy, and to evaluate its anti-allergic activity in such a clinical condition. METHODS: The study was designed as parallel groups, double-blind, placebo-controlled, randomized. Twenty allergic children were enroled and subdivided in two groups, receiving a 4 week treatment during the pollen season. The following parameters were monitored: clinical symptoms evaluated by the allergist before and after treatment and by the patients through a daily diary card, inflammatory cells count, expression of ICAM-1 on nasal epithelial cells, inflammatory mediator levels in nasal lavage and peripheral blood before and after treatment, and pollen counts. RESULTS: This study shows that cetirizine treatment is able to reduce: clinical symptoms (P < 0.01), inflammatory cell infiltrate (P < 0.03), ICAM-1 expression on epithelial cells (P < 0.05), and soluble ICAM-1 (P < 0.05) and ECP (P < 0.05) in nasal lavage. CONCLUSION: Cetirizine is able to clinically improve nasal symptoms due to pollen allergy and to reduce allergic inflammation, which is related to allergen exposure.  相似文献   

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