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Background Mould‐induced atopic respiratory diseases are a worldwide problem. Characterization of fungal allergens is of major clinical importance. Objective We identified a novel transaldolase family allergen of Cladosporium and Penicillium species. Methods Fungal allergens were identified by immunoblotting, peptide mass mapping and partial sequencing, cDNA cloning and IgE epitope mapping. Results A 36.5 kDa IgE‐binding component in a partially purified C. cladosporioides preparation was identified. Mass spectrometric analyses suggest that this novel IgE‐reacting allergen is a transaldolase. A corresponding full‐length 1246 bp cDNA encoding a polypeptide of 325 residues was isolated. The newly identified transaldolase allergen has been designated as Cla c 14.0101. The cDNA encoding the Pencillium chrysogenum transaldolase was isolated by RT‐PCR according to the cDNA sequence encoding a P. chrysogenum Wisconsin 54‐1255 hypothetical protein. The purified rCla c 14.0101 protein reacted with IgE antibodies in 10 (38%) of 26 Cladosporium cladosporioides‐sensitized asthmatic patients. Nine of the 10 rCla c 14.0101‐positive sera have IgE binding against the recombinant Penicillium transaldolase (rPen ch 35.0101). Among the eight fungal transaldolase‐positive sera tested, three showed IgE binding against the recombinant human transaldolase. To determine cross‐reactivity between the Cladosporium and Penicillium fungi, IgE cross‐reactivity was detected between these two fungal transaldolase allergens by inhibition assays. Both the N‐ and the C‐terminal fragments of Cla c 14.0101 were recognized by IgE antibodies. The C‐terminal IgE‐reacting determinant was narrowed down to a region encompassing Thr257 to Ser278 of Cla c 14.0101. It was mapped onto a loop‐like structure of a 3D model constructed for Cla c 14.0101. Conclusion and Clinical Relevance We identified transaldolase as a novel and IgE cross‐reactive allergen family of C. cladosporioides and P. chrysogenum. In addition, an IgE‐reacting fragment (Thr257 to Ser278) was pinpointed to a loop‐like structure on Cla c 14.0101. Results obtained provide important information in clinical mould allergy. Cite this as: H. Chou, M. F. Tam, C.‐H. Chiang, C.‐T. Chou, H.‐Y. Tai and H.‐D. Shen, Clinical & Experimental Allergy, 2011 (41) 739–749. 相似文献
954.
Yaw-Huei Hwang En-Ju Chou Ching-Wen Chang Chih-Chieh Chen Chi-Kung Ho Chih-Liang Chou 《Archives of environmental & occupational health》2013,68(1):78-84
The authors suspected that suspended onion particles contributed to corneal ulcers in onion harvesters in southern Taiwan. In the present study, the authors used manikins to study suspended onion particles in fields in an effort to simulate typical conditions experienced by onion harvesters. An animal eye-exposure simulation study was also performed by the authors, who impacted suspended soil grains or onion particles onto the corneas of guinea pigs via aerosol generated from the Palas® dispersion nozzle. The average size of 25.9 μm for suspended particles collected during the digging of onions was the largest one of those for various harvesting activities. Some onion skin flakes were found in samples obtained from gathering and packing activities; the typical flake size was approximately 3.5 × 2.5 mm2. The results of the animal study indicated that the size of soil grains has a demonstrable effect on the severity of corneal injury (p = .009). With respect to onion skin flakes, wind velocity was also associated significantly with the occurrence of corneal injury (p = .0004). A wind velocity threshold of 7 m/sec is recommended for the maintenance of safety, and if the wind speed exceeds this threshold level, workers should not engage in harvesting activities. Furthermore, use of appropriately designed goggles is necessary for the protection of onion harvesters who work in high-wind conditions. 相似文献
955.
The goal of the current study is to examine the role of poor migration planning as a moderator for the effects of two post-migration
factors, namely acculturation stress and quality of life, on symptoms of depression. Using a random sample of 347 Hong Kong
new migrants from a 1-year longitudinal study, we used multiple regression analyses to examine both the direct and interaction
effects of poorly planned migration, acculturation stress, and quality of life on depressive symptoms. Although poorly planned
migration did not predict depressive symptoms at 1-year follow-up, it did exacerbate the detrimental effect of the two post-migration
factors, namely high stress or low quality of life (both also measured at baseline) on depressive symptoms at this stage.
Our results indicate that preventive measures must be developed for new immigrants in Hong Kong, especially for those who
were not well prepared for migration. 相似文献
956.
Fuzzy clustering of gait patterns of patients after ankle arthrodesis based on kinematic parameters.
Kinematic parameters for 10 normal subjects and 10 patients with ankle arthrodesis are grouped using the fuzzy cluster paradigm. The features chosen for clustering are Euler angles of the sagittal plane in the hindfoot, the forefoot and combined hindfoot and forefoot joints. Gait patterns are identified using information provided by cluster validity techniques, giving three, three and two clusters for the hindfoot, forefoot and combined hindfoot and forefoot joints, respectively. The cluster centers represent distinct walking strategies adopted by normal subjects and patients after ankle arthrodesis. Utilizing angle values normalized by gait cycle, it is possible to classify any subject and to generate an individual's membership value for each of the clusters. The clinical utility of the fuzzy clustering approach is demonstrated with data for subjects with ankle arthrodesis, where changes in membership of the clusters provide an objective technique for measuring changes of gait pattern after ankle arthrodesis. This approach can be adopted to study other clinical entities where different cluster centers would be established using the algorithm provided in this study. 相似文献
957.
Hung-Jen Lai Chung-Huang Yu Hung-Chan Kao Wen-Chuan Chen Chi-Wei Chou Cheng-Kung Cheng 《Medical engineering & physics》2010,32(6):623-629
The fatigue failure of thermoplastic ankle–foot orthoses (AFOs) was observed in clinics. However, there was no standard evaluation for the AFOs to enhance the understanding of how AFOs become more readily acceptable to patients. Therefore, this study aimed to develop an ankle–foot simulator (AFS) as a testing apparatus for AFOs, and performed a pilot test to investigate the failure mechanism of anterior ankle–foot orthosis (AAFO). The accuracy and repeatability of the AFS during cyclic walking, cyclic stepping and cyclic stepping with the AAFO in sagittal plane were measured. The root mean square errors (RMSEs) of cyclic walking of AFS compared to a target gait data were less than 80.52N and 2.55° in the vertical ground reaction force and in the kinematics, respectively. The RMSE of ankle plantarflexion and dorsiflexion of AFS in the cyclic stepping tests were less than 1.25°. The repeatability was assessed by standard deviation, which were less than 9.46N and 0.72° in all testing conditions. A typical failure progression of five AAFOs was observed and graded for four phases under cyclic stepping test. Failure always initiated at the junction of anterior tarsal bar and lateral (or medial) bar of the AAFOs, from which the rest failures were extended. It is suggested that this junction must be reinforced or prevented the stress concentration to elongate the endurance of AAFO. 相似文献
958.
M. P. Chen S. H. Yang C. H. Chou K. C. Yang C. C. Wu Y. H. Cheng Feng-Huei Lin 《Inflammation research》2010,59(8):587-595
Objective
The objective of the study is to evaluate the effect of ferulic acid (FA), an antioxidant from the Chinese herb Dong-Gui [Chinese angelica, Angelica sinensis (Oliv.) Diels], on the regulation of various genes in hydrogen peroxide-stimulated porcine chondrocytes at the mRNA level. 相似文献959.
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