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81.
An ELISA-based method for measurement of food-specific IgE antibody in mouse serum: an alternative to the passive cutaneous anaphylaxis assay 总被引:1,自引:0,他引:1
Birmingham N Payankaulam S Thanesvorakul S Stefura B HayGlass K Gangur V 《Journal of immunological methods》2003,275(1-2):89-98
Passive cutaneous anaphylaxis (PCA) assay has been a gold standard method to measure allergen-specific IgE antibody (ASIgE Ab) levels in allergy mouse models. Many factors including stringent guidelines for laboratory animal use make PCA a difficult choice. Therefore, alternative methods are needed that can be readily applied for measurement of specific IgE antibody levels in mouse serum. Herein we describe a novel ELISA-based method that is more sensitive in comparison to PCA, IgE isotype-specific (because it has little cross-reactivity with IgG1 or IgG2a isotype) and highly reproducible (<10% inter- or intra-assay variation). Furthermore, we demonstrate the utility of this assay to measure specific IgE Ab against a variety of food extracts including chicken egg, peanut, almond, filbert/hazelnut and sweet potato. These findings are of particular interest to those who are seeking (i) to measure food-extract-specific IgE antibody in animal models and (ii) an alternative to the animal-based PCA method to measure mouse IgE antibodies. 相似文献
82.
Analysis of the coxsackievirus B-adenovirus receptor gene in patients with myocarditis or dilated cardiomyopathy 总被引:1,自引:0,他引:1
Bowles NE Javier Fuentes-Garcia F Makar KA Li H Gibson J Soto F Schwimmbeck PL Schultheiss HP Pauschinger M 《Molecular genetics and metabolism》2002,77(3):257-259
Myocarditis and dilated cardiomyopathy (DCM) are common causes of morbidity and mortality in children and adults, most commonly due to infection with coxsackievirus B or adenovirus. Increased expression of the common human coxsackievirus B-adenovirus receptor (CAR) has been reported in patients with DCM. We investigated the CAR gene in patients with acquired or familial myocarditis/DCM for mutations/polymorphisms. Several polymorphisms or intronic substitutions, distant from the intron-exon boundaries, were identified but no mutations. Based upon these data it appears that CAR gene mutations are not a major host determinant in the development of myocarditis and DCM. 相似文献
83.
84.
Cell-free translation of avian erythroblastosis virus RNA yields two specific and distinct proteins with molecular weights of 75,000 and 40,000 总被引:13,自引:0,他引:13
Avian erythroblastosis virus (AEV) 28 S virion RNA was translated in vitro in cell-free reticulocyte lysates. Two AEV-specific proteins, one of 75,000 (p75) the other of 40,000 (p40) molecular weight, were detected. p75 is a fusion protein containing gag-specific and AEV-specific peptides. It appears to be translated from the 5′-end of the 28 S AEV RNA and is indistinguishable from the p75 detected in AEV-transformed cells (Hayman et al., 1979). p40 does not share sequences with any viral structural protein. It also contains peptides distinct from those of p75, but one of the five identifiable p40 peptides comigrates with one of the p75 peptides. p40 is translated from a 20 S RNA which contains the 3′-half of the AEV-specific sequences of the genome. These two proteins account for all of the coding capacity of the AEV-specific gene sequences in the 28 S AEV RNA and are candidates for leukemia-specific transforming proteins. 相似文献
85.
Erik R Svendsen Karin B Yeatts David Peden Susan Orton Neil E Alexis John Creason Ronald Williams Lucas Neas 《Annals of allergy, asthma & immunology》2007,99(3):244-253
BACKGROUND: Identifying baseline inflammatory biomarkers that predict susceptibility to size-specific particulate matter (PM) independent of gaseous pollutants could help us better identify asthmatic subpopulations at increased risk for the adverse health effects of PM. OBJECTIVE: To evaluate whether the association between lung function and exposure to ambient levels of PM less than 2.5 microm in diameter (PM2.5) (fine) and 10 to 2.5 microm in diameter (PM(10-2.5)) (coarse) in children with persistent asthma differed across baseline measures of inflammation and innate immune activation. METHODS: We performed a panel study on a local population of 16 children with persistent asthma and evaluated daily pulmonary function (percentage of predicted peak expiratory flow and forced expiratory volume in 1 second) while concurrently measuring daily PM2.5 and PM(10-2.5) exposure from a central site in Chapel Hill, North Carolina. The children underwent a baseline medical evaluation that included assessment of several immunoinflammatory biomarkers in peripheral blood. RESULTS: Children without measurable CD14 expression on circulating neutrophils had significantly reduced pulmonary function (forced expiratory volume in 1 second and peak expiratory flow) with each interquartile range (IQR) increase in PM2.5 (IQR = 8.5 microg/m3) and PM(10-2.5) (IQR = 4.1 microg/m3) concentration, unlike children with measurable CD14 expression (P < .001 for interaction). CONCLUSIONS: Asthmatic children with muted surface expression of CD14 on circulating neutrophils may have a decreased capacity to respond to bacterial components of PM. 相似文献
86.
Holger Arndt Paul Kubes Matthew B. Grisham Enrique Gonzalez D. Neil Granger 《Inflammation》1992,16(5):549-559
The objective of this study was to determine the turnover rate of the extravascular pool of granulocytes in different regions of the feline gastrointestinal tract. Leukocyte emigration from the vasculature was prevented over a 48-h period by repeated intravenous injections of a monoclonal antibody (MAb IB4) directed against the leukocyte adhesion glycoprotein complex CD11/CD18. Tissue-associated myeloperoxidase (MPO) activity was used to monitor the total tissue granulocyte pool at 0.5, 12, 24, and 48 h after MAb IB4 administration. The mucosal layer of the duodenum, jejunum, ileum, and colon exhibited different kinetics of granulocyte clearance, with average life-spans (t1/2) ranging between 6.9 (colon) and 10.4 h (duodenum). Granulocyte clearance rates of 0.5 × 106 and 2.4 x 106 cells/h/g tissue were estimated (from measured values oft1/2 and tissue granulocyte pool) for the small bowel and colonie mucosae, respectively. The submucosal layer of the intestine exhibited a biphasic reduction in tissue MPO activity following immunoneutralization of CD11/CD18, with an initialt1/2 0.5 h followed by at1/2 of 36–60 h. The initial rapid decline in tissue MPO suggests that a significant fraction of granulocytes in the submucosa is localized in a readily exchangeable pool (e.g., marginated cells within the vasculature). The results of this study indicate that the average life-span of resident granulocytes varies significantly between different regions of the gastrointestinal tract, with the intestinal mucosa exhibiting at1/2 comparable to that previously reported for circulating feline neutrophils (R 8 h). 相似文献
87.
An eighth locus for autosomal dominant retinitis pigmentosa is linked to chromosome 17q 总被引:5,自引:2,他引:5
Bardienb Soraya; Ebenezer Neil; Greenberg Jacquie; Inglehearn Chris F.; Bartmann Lecia; Goliath Rene; Beighton Peter; Ramesar Rajkumar; Bhattacharya Shomi S. 《Human molecular genetics》1995,4(8):1459-1462
Retinitis pigmentosa is one of the most common causes of severevisual handicap in middle to late life. Prior to this report,seven loci had previously been mapped for the autosomal dominantform of this disorder (adRP). We now report the identificationof a novel adRP locus on chromosome 17q. To map the new locus,we performed linkage analysis with microsatellite markers ina large South African kindred. After exclusion of 13 RP candidategene loci (including rhodopsin and peripherin-RDS), we obtainedsignificant positive lod scores at zero recombination fraction( 相似文献
88.
Attention mediates the acquisition and encoding of information about the world and is central to motor action. Heart rate deceleration and behavioral inhibition are sensitive indices of the attentional process, but it is unknown whether these indices are valid in the context of overt action. The current study investigated the relationship between visual attention, action, and heart rate during reaching in 7(1/2)-month-old infants. We found that infants showed prolonged looking and large heart rate decelerations on reaching and looking trials. We conclude that overt action itself does not prevent the autonomic and behavioral changes that are also seen in attention to simple visual displays and that attention is maintained throughout the act of reaching. 相似文献
89.
The changes in the tensile toughness (U), degree of crystallinity (%C), melting temperature (Tm), lamella thickness, and lamella alignment of uncrosslinked and unaged GUR 1150HP ultra-high-molecular-weight polyethylene specimens, following different sterilization treatments (none, gamma-irradiation in air, gamma-irradiation in a nitrogen-rich atmosphere, ethylene oxide gas, and gas plasma) were determined. For each of the properties - U, %C, and Tm - the only significant difference in the mean value was found between the set of specimens gamma-irradiated in air, on the one hand, and each of the other sets, on the other hand. It was found that lamella thickness showed little change between the groups of specimens but there was a significant difference in the lamella orientation between the set of specimens that had been gamma-irradiated in air, on the one hand, and each of the other sets, on the other. It thus appears that the changes seen in the physical and mechanical properties determined may be a reflection of the change in the polymer's lamella alignment. 相似文献
90.
Chromophobe renal cell carcinoma with sarcomatoid transformation 总被引:2,自引:0,他引:2
We present a rare case of a chromophobe renal cell carcinoma that progressed to a high-grade spindle cell sarcoma. The tumor affected a 50-year-old man who had presented with right upper quadrant discomfort and hematuria and subsequently underwent a right radical nephrectomy. Microscopically, the tumor was composed of two distinct components, a chromophobe renal cell carcinoma and a sarcomatoid component. The sarcomatoid component had exhibited aggressive behavior by spreading to a regional lymph node. This case report shows that chromophobe carcinoma can develop a sarcomatoid transformation with a high propensity for invasive growth and metastasis. 相似文献