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41.
Food-dependent exercise-induced anaphylaxis in childhood   总被引:1,自引:0,他引:1  
The clinical syndrome of food-dependent exercise-induced anaphylaxis (FDEIA) is typified by the onset of anaphylaxis during (or soon after) exercise which was preceded by the ingestion of the causal food allergen/s. In FDEIA, both the food allergen/s and exercise are independently tolerated. FDEIA is an uncommon allergic condition in childhood, but nonetheless is an important differential diagnosis to be considered when faced by a child who has experienced exercise-associated anaphylaxis. The diagnosis of FDEIA is heavily dependent on the clinical history. Allergy tests may need to be performed to a broad panel of food and food additives. Modified exercise challenges (performed with and without prior ingestion of food) are frequently required as allergy test results frequently return low-positive results. A diagnosis of FDEIA facilitates the safe independent return to exercise and reintroduction of foods for patients who otherwise may unnecessarily avoid exercise and/or restrict their diet. The natural history of FDEIA is unknown; however, a safe return is usually achieved when the ingestion of the causal food allergen/s and exercise are separated.  相似文献   
42.
Food allergies are increasing in prevalence, and with it, IgE testing to foods is becoming more commonplace. Food-specific IgE tests, including serum assays and prick skin tests, are sensitive for detecting the presence of food-specific IgE (sensitization), but specificity for predicting clinical allergy is limited. Therefore, positive tests are generally not, in isolation, diagnostic of clinical disease. However, rationale test selection and interpretation, based on clinical history and understanding of food allergy epidemiology and pathophysiology, makes these tests invaluable. Additionally, there exist highly predictive test cutoff values for common allergens in atopic children. Newer testing methodologies, such as component resolved diagnostics, are promising for increasing the utility of testing. This review highlights the use of IgE serum tests in the diagnosis of food allergy.  相似文献   
43.
BACKGROUND: Cereals are among the major foods that account for food hypersensitivity reactions. Salt-soluble proteins appear to be the most important allergens contributing to the asthmatic response. In contrast, very limited information is available regarding cereal allergens responsible for allergic reactions after ingestion of cereal proteins. OBJECTIVE: The aim of this study was to evaluate the allergenic reactivity of ingested and inhaled cereal allergens in different ages, in order to investigate if the response to different allergens would depend on the sensitization route. METHODS: We included 66 patients in three groups. Group 1: 40 children aged 3 to 6 months who suffered from diarrhoea, vomiting, eczema or weight loss after the introduction of cereal formula in their diet and in which a possibility of coeliac disease was discarded. Group 2: 18 adults with food allergy due to cereals tested by prick tests, specific IgE and food challenge. Group 3: eight patients previously diagnosed as having baker's asthma. Sera pool samples were collected from each group of patients and IgE immunoblotting was performed. RESULTS: We found an important sensitization to cereal in the 40 children. The most important allergens were wheat followed by barley and rye. Among the adults with cereal allergy, sensitization to other allergens was common, especially to Lolium perenne (rye grass) pollen. Immunoblotting showed similar allergenic detection in the three groups. CONCLUSION: Clinically significant reactivity to cereal may be observed in early life. Inhalation and ingestion routes causing cereal allergy seem to involve similar allergens. The diet control was more effective in children. The possibility of cereal allergy after the introduction of cereal formula during the lactation period should not be underestimated.  相似文献   
44.
BACKGROUND: Food allergy to wheat induces different symptoms as atopic eczema/dermatitis syndrome (AEDS), urticaria and more severe reactions as wheat-dependent exercise-induced anaphylaxis (WDEIA). Different gliadin classes are involved in this allergy but IgE-binding epitopes are known only on omega5-gliadins and for WDEIA cases. OBJECTIVES: The aim of the study was to identify IgE-binding epitopes on several gliadin classes and for several patients with different symptoms and ages. METHODS: Eleven sera were analysed by pepscan with overlapping synthetic peptides. RESULTS: Sera from five patients with anaphylaxis, urticaria or WDEIA, displayed strong IgE-binding to sequential epitopes of the repetitive domains of alphabeta, gamma, omega2 or omega5-gliadins with two immunodominant epitopes on omega5-gliadin and a consensus motif of the type QQX1PX2QQ (X1 being L, F, S or I and X2 Q, E or G). One patient allergic to deamidated wheat proteins also had IgE to a repetitive peptide of gamma and omega2-gliadins of the type QPQQPFP. Sera from four patients with AEDS detected no linear epitopes on gliadins, despite the fact that they contained specific IgE to alpha, beta, gamma or omega-gliadins. One child with AEDS recognized cysteine-containing sequences in the nonrepetitive domains of alphabeta and gamma-gliadins. CONCLUSION: B epitopes in wheat allergy were different from B epitopes of coeliac disease. Differences exist in IgE-binding epitopes between patients with food allergy to wheat. IgE from those suffering from WDEIA, anaphylaxis and urticaria detected sequential epitopes in the repetitive domain of gliadins whereas IgE from AEDS patients probably recognized conformational epitopes.  相似文献   
45.
The ventral part of the cat oral pontine reticular nucleus (vRPO) is the site in which microinjections of small dose and volume of cholinergic agonists produce long-lasting rapid eye movement sleep with short latency. The present study determined the precise location and proportions of the cholinergic brainstem neuronal population that projects to the vRPO using a double-labeling method that combines the neuronal tracer horseradish peroxidase–wheat germ agglutinin with choline acetyltransferase immunocytochemistry in cats. Our results show that 88.9% of the double-labeled neurons in the brainstem were located, noticeably bilaterally, in the cholinergic structures of the pontine tegmentum. These neurons occupied not only the pedunculopontine and laterodorsal tegmental nuclei, which have been described to project to other pontine tegmentum structures, but also the locus ceruleus complex principally the locus ceruleus and peri-, and the parabrachial nuclei. Most double-labeled neurons were found in the pedunculopontine tegmental nucleus and locus ceruleus complex and, much less abundantly, in the laterodorsal tegmental nucleus and the parabrachial nuclei. The proportions of these neurons among all choline acetyltransferase positive neurons within each structure were highest in the locus ceruleus complex, followed in descending order by the pedunculopontine and laterodorsal tegmental nuclei and then, the parabrachial nuclei. The remaining 11.1% of double-labeled neurons were found bilaterally in other cholinergic brainstem structures: around the oculomotor, facial and masticatory nuclei, the caudal pontine tegmentum and the praepositus hypoglossi nucleus. The disperse origins of the cholinergic neurons projecting to the vRPO, in addition to the abundant noncholinergic afferents to this nucleus may indicate that cholinergic stimulation is not the only or even the most decisive event in the generation of REM sleep.  相似文献   
46.
The flow cytometry and chromosome imaging method were jointly used for analyzing genome content and chromosomal DNA content of hexaploid wheat (AABBDD), hexaploid triticale (AABBRR), tetraploid wheat (AABB), and AA, BB, DD genome donors and RR genome rye. Their genome sizes were 34.4 pg, 40.9 pg, 26.2 pg, 12.1 pg, 13.7 pg, 10.5 pg, and 16.9 pg, respectively. The 2C nuclear DNA content of BB genome donor with 13.7 pg was the highest value among the other genome donors, AA or DD. The genome content of tetraploid wheat, unlike hexaploid wheat or hexaploid triticale, was larger than the sum of the genomes of AA and BB genome donors. The DNA content of each chromosome ranged from 1.22 pg in DD genome donor to 2.61 pg in rye. Each chromosome peak was divided into three to four groups. Only one chromosome was included in the highest chromosomal DNA peak in hexaploid wheat, tetraploid wheat, DD genome donor and rye but two chromosomes in AA, BB genome donors, and hexaploid triticale. Correlation between 2C nuclear DNA content and chromosome density volume was the highest value compared with the other chromosomal parameters of chromosome area, or chromosome length.  相似文献   
47.
The aim of this study was to determine if extracts from selected spices (caraway, ginger, chili, sweet peppers, anise, sesame, nutmeg and black pepper) might be harmful to people suffering from celiac disease, wheat allergy or non-celiac gluten sensitivity. All of these spice extracts exhibited some reaction to antibodies found in sera from two celiac patients and to sera from rabbits that had been sensitized with the specific peptides, QQQPP, PQQQ and QQQP. These peptides had sequences that might be included in active epitopes for celiac disease and wheat allergy. Methodology followed in this study included ELISA, SDS-PAGE and immunoblotting. The observed reactivities suggest that spice proteins might produce adverse reactions in celiac patients, patients with various wheat allergies or with non-celiac gluten sensitivity. However, further work would be needed to elucidate this possibility.  相似文献   
48.
Varjonen E  Vainio E  Kalimo K 《Allergy》2000,55(4):386-391
BACKGROUND: Cereal grains are recognized as the cause of adverse reactions in some patients exposed to grain or flour by either inhalation or ingestion. Cereal-related diseases, such as celiac disease and baker's asthma, have been well studied and the causative cereal proteins have been characterized. Although cereals form an essential part of daily nutrition, the allergenic proteins causing symptoms on ingestion in atopic dermatitis (AD) have remained obscure. In this study, we have investigated the allergenic fraction of wheat in AD. METHODS: Skin prick tests (SPT) with a NaCl wheat suspension and the ethanol-soluble wheat gliadin were performed on 18 wheat-challenge-positive or -negative children with AD, six adult AD patients with suspected cereal allergy, and one adult with wheat-dependent exercise-induced urticaria/anaphylaxis. Serum total IgE and specific IgE-antibody levels to wheat and gluten were measured with the radioallergosorbent test (RAST) simultaneously. In addition serum samples of all 25 patients were analyzed by IgE immunoblotting with the ethanol-soluble wheat-protein extract. RESULTS: Thirteen of the AD children were wheat-challenge-positive, 11/12 of them appeared to be positive with gliadin SPT, and all had an elevated gluten RAST value. Those challenge-negative were negative with both gliadin SPT and gluten RAST. Positive wheat SPT and RAST alone were not associated with positive challenges. Four of the adult patients responded to a cereal-free diet, although only two of them appeared to be positive with gliadin SPT and gluten RAST. A broad and intensive staining of gliadin peptides in IgE-immunoblotting studies was seen in challenge-positive children with positive gliadin SPT and/ or gluten RAST. Besides staining of peptides in the main gliadin area of 30-46 kDa, a characteristic finding was the staining of small, <14-kDa proteins with sera of challenge- and gliadin-SPT-positive patients. CONCLUSIONS: We found that wheat-allergic AD patients have IgE antibodies against gliadin that can be detected by both SPT and the sensitive immunoblotting method. This suggests that gliadin peptides are important allergens, and ingestion of wheat causes symptoms of AD. A broad and intensive IgE staining was seen of gliadin peptides against both the previously characterized peptides in the main gliadin area and small, previously uncharacterized peptides of less than 14 kDa. The gliadin SPT and gluten RAST are good screening methods. Further characterization of the IgE-stained gliadin proteins is needed.  相似文献   
49.

Aims

To explore the ultrastructure of interstitial cells in the upper lamina propria of the human bladder, to describe the spatial relationships and to investigate cell‐cell contacts.

Methods

Focused ion beam scanning electron microscopy (FIB‐SEM), 3‐View SEM and confocal laser scanning microscopy were used to analyze the 3D ultrastructure of the upper lamina propria in male and female human bladders.

Results

3View‐SEM image stacks as large as 59 × 59 × 17 μm3 (xyz) at a resolution of 16 × 16 × 50 nm3 and high resolution (5 × 5 × 10 nm3) FIB‐SEM stacks could be analyzed. Interstitial cells with myoid differentiation (mIC) and fibroblast like interstitial cells (fIC) were the major cell types in the upper lamina propria. The flat, sheet‐like ICs were oriented strictly parallel to the urothelium. No spindle shaped cells were present. We furthermore identified one branched cell (bIC) with several processes contacting urothelial cells by penetrating the basal membrane. This cell did not make any contacts to other ICs within the upper lamina propria. We found no evidence for the occurrence of telocytes in the upper lamina propria.

Conclusions

Comprehensive 3D‐ultrastructural analysis of the human bladder confirmed distinct subtypes of interstitial cells. We provide evidence for a foremost unknown direct connection between a branched interstitial cell and urothelial cells of which the functional role has still to be elucidated. 3D‐ultrastructure analyses at high resolution are needed to further define the subpopulations of lamina propria cells and cell‐cell interactions.  相似文献   
50.
以小麦(Triticum aestivum L.)品种石4185为材料,研究了45 ℃处理0~120 min对小麦未成熟籽粒谷甘胱肽转移酶(GST)、谷胱甘肽还原酶(GR)、过氧化氢酶(CAT)和过氧化物酶(POD)活性, 超微弱发光,种子萌发和愈伤组织诱导的影响.结果表明,热休克处理使未成熟籽粒萌发率、愈伤组织诱导率和GST活性明显增加,且其作用随处理时间的延长而增大;在处理过程中, CAT活性先减少后增加,热休克对GR活性无明显影响.GST的活性与蛋白质质量分数呈显著正相关.  相似文献   
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