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31.
BACKGROUND: Chronic urticaria (CU) in childhood remains a challenge for investigation, and its etiology is largely unknown. Autoantibodies to the high-affinity IgE receptor (FcepsilonRI) are believed to play a role in the pathogenesis of this disease in adults. OBJECTIVE: To determine the prevalence of autoantibodies to FcepsilonRIalpha on basophils in children with CU vs atopic eczema dermatitis syndrome (AEDS). METHODS: Eighty children with CU were compared with 38 children with AEDS. In addition to complete blood cell counts and total IgE measurements, CAP-RASTs to egg, codfish, soy, milk, and peanut were performed. Stool samples were examined for parasites, and autologous serum skin testing and a functional anti-FcepsilonRIalpha assay were conducted to detect autoantibodies. RESULTS: No significant differences were observed between children with CU and controls in mean basophil or eosinophil counts. Twenty (26%) of 77 children with CU and 31 (82%) of 38 with AEDS had positive CAP-RAST results (P < .001). Only 2.5% of the children with CU and 0% with AEDS had stool samples positive for parasites (P = .005). Anti-FcepsilonRIalpha autoantibodies were positive in 37 (47%) of 78 children with CU and in none of 33 with AEDS. Non-IgG histamine-releasing factors were found in 10 (13%) of 78 children with CU. CONCLUSIONS: Children have a similar prevalence of autoantibodies to the FcepsilonRIalpha as has been previously published for adults. Few have type I allergies, and parasite infestation is also uncommon. Further studies are required to investigate the predictive value of the autoantibodies in these children with respect to clinical profile, requirements for medications other than antihistamines, and remission rates.  相似文献   
32.
Spinal muscular atrophy (SMA) is, after Duchenne muscular dystrophy,the most common neuromuscular disorder in childhood. The generesponsible for childhood SMA has been mapped to the q11. 2– q13. 3 region of chromosome 5. We have extended ourlinkage studies of SMA In the French - Canadian population toInclude microsatellite markers at the D5S125, D5S351, D5S435,JK53CA1/ 2 and MAPI B locl. These markers span about 4 cM ofthe SMA candidate region. We observed significant evidence forlinkage between SMA and all the markers tested. The analysisof recombinant chromosomes provide evidence for the followinggenetic order: D5S125-D5S435-MAP1B-3'-JK53CA1/2 and places D5S351proximal to JK53CA1/2. Furthermore, we confirm the current localizationof the SMA gene distal to D5S435. Finally, we provide demonstrationof significant linkage disequilibrium between childhood-onsetSMA and four of the five marker loci, D5S125, D5S435, D5S351and JK53CA1/2. Analysis of SMA-region haplotypes suggests thatthere may be a predominant SMA allele that is present on about17% of SMA chromosomes in this sample of the French - Canadianpopulation. We conclude that the observed linkage disequilibriumis likely due to genetic drift among regions of Quebec, consistentwith this population's early history.  相似文献   
33.
The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers, and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant, and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed and sensitive manner.  相似文献   
34.
Rhodococcus equi causes severe pyogranulomatous pneumonia in foals and in immunocompromised humans. Replication of virulent isolates within macrophages correlates with the presence of a large plasmid which encodes a family of seven virulence-associated proteins (VapA and VapC to VapH), whose functions are unknown. Although cell-mediated immunity is thought to be crucial in eliminating R. equi infection, antibody partially protects foals. The antibody response to both VapA and VapC was similar in six adult horses and six naturally exposed but healthy foals, as well as in eight foals with R. equi pneumonia. The immunoglobulin G (IgG) subisotype response of pneumonic foals to Vap proteins was significantly IgGb biased and also had a trend toward higher IgGT association compared to the isotype association of antibody in adult horses and healthy exposed foals. This suggests that in horses, IgGb and IgGT are Th2 isotypes and IgGa is a Th1 isotype. Furthermore, it suggests that foals which develop R. equi pneumonia have a Th2-biased, ineffective immune response whereas foals which become immune develop a Th1-biased immune response. Pneumonic foals had significantly more antibody to VapD and VapE than did healthy exposed foals. This may indicate a difference in the expression of these two Vap proteins during persistent infection. Alternatively, in pneumonic foals the deviation of the immune response toward VapD and VapE may reflect a bias unfavorable to R. equi resistance. These data indicate possible age-related differences in the equine immune response affecting Th1-Th2 bias as well as antibody specificity bias, which together favor the susceptibility of foals to R. equi pneumonia.  相似文献   
35.
A total of 191 Campylobacter jejuni and 125 Campylobacter coli were isolated from the intestinal content of 398 chickens, 421 cattle, and 203 pigs. All 108 chicken isolates and 73 of 80 cattle isolates were C. jejuni, but 115 of the 118 pig isolates were C. coli. A total of 84% of the C. jejuni and 64% of the C. coli isolates were typed on the basis of thermostable antigens with 20 antisera prepared against frequently occurring serotypes in Campylobacter enteritis in man (15 C. jejuni, 6 C. coli serotypes). A total of 96% of the chicken isolates and 67% of the cattle isolates belonged to 11 C. jejuni serotypes that occur most frequently in human cases of enteritis (serotypes 1, 2, 3, 4, 5, 13/16, 18, 21, 23, 31, and 36). Serotype 8, a relatively common human isolate, was not recovered. The C. coli isolates from pigs belonged to serotypes uncommon among human isolates.  相似文献   
36.
37.
BackgroundCurrent data regarding the risk of malignancy in a large thyroid nodule with benign fine-needle aspiration biopsy(FNAB) is conflicting. We investigated the impact of patient age on the risk of malignancy in nodules≥4 cm with benign cytology.MethodsWe performed a single-institution retrospective review of patients who underwent surgery from 07/2008–08/2019 for a cytologically benign thyroid nodule ≥4 cm. The relationship between malignant histopathology and patient and ultrasound features was assessed with multivariable logistic regression.ResultsOf 474 nodules identified, 25(5.3%) were malignant on final pathology. In patients <55 years old, 21/273(7.7%) nodules were malignant, compared to 4/201(2.0%) in patients ≥55. Patient age ≥55 was independently associated with significantly lower risk of malignancy(OR:0.2,95%CI:0.1–0.7,p = 0.011). Increasing nodule size >4 cm and high-risk ultrasound features were not associated with risk of malignancy(OR:1.0,95%CI:0.7–1.4,p = 0.980, and OR:9.6,95%CI:0.9–107.8,p = 0.066, respectively).ConclusionsPatients <55 years old are 3.7-fold more likely to have a falsely benign FNA biopsy in a nodule≥4 cm.  相似文献   
38.
Sixteen pathologically confirmed and 14 suspected cases of a new disease entity, fibrosing colonopathy, have been described in the UK and the US in children with cystic fibrosis since 1991. The patterns of use of pancreatic enzyme supplements in cases were compared with use in controls and in the market, in the 2 years prior to surgery for fibrosing colonopathy or the equivalent date in controls. The disease was only found in children with cystic fibrosis who had received brands of pancreatic enzyme supplement coated with methacrylic acid copolymer, for a period of at least 6 months. The risk was dose-related. No cases could be identified in children who had only received other pancreatic enzyme formulations, irrespective of the strength of the formulation or the dose.  相似文献   
39.
BACKGROUND: The less favorable trend in smoking prevalence in women compared to men may be due to lower cessation rates. We analyzed determinants of spontaneous smoking cessation with particular reference to gender differences. METHODS: Data on smoking were collected by questionnaire in three samples of the adult population, examined for the first time at intervals between 1976 and 1984. In total 11,802 (59%) subjects were smokers, and 9085 of them attended a reexamination after 5 years. Ten to 16 years later 6053 were examined once again. Logistic regression was performed to study the relation of determinants to having quit after 5 and 10-16 years. RESULTS: The prevalence of quitting was 12 and 22% at first and second follow-up, respectively. At both reexaminations, quitting smoking was positively associated with male sex and cigar smoking and negatively associated with the amount of tobacco smoked, inhalation, and alcohol consumption. Furthermore, in women, smoking cessation was positively associated with level of education and body mass index (BMI). Smoking cessation was not affected by cohabitation status, leisure activity, or bronchitis symptoms. CONCLUSIONS: Smoking cessation initiatives should be targeted at heavy cigarette smokers, and at women, in particular the lean and poorly educated.  相似文献   
40.
1-Cyano-3,4-epithiobutane (CEB), a naturally occurring nitrile derived from cruciferous plants, causes nephrotoxicity and increased renal glutathione (GSH) concentration in male F-344 rats. This CEB-induced nephrotoxicity is dependent on GSH conjugation and bioactivation. The objectives of the present study were to investigate the effect of CEB on several xenobiotic-metabolizing enzymes and to evaluate the effect of modulators of GSH transport and metabolism on CEB-induced nephrotoxicity and GSH concentration. Animals received 125 mg kg-1 CEB alone or following pretreatment with one of three selective inhibitors of GSH metabolism: acivicin, probenecid or aminooxyacetic acid. There were no significant alterations in epoxide hydrolase (EH), P-450, ethoxyresorufin O-deethylase (EROD) or pentoxyresorufin O-depentylase (PROD) enzyme activity, but renal glutamyl cysteine synthetase (GCS) activity was decreased at 12 and 24 h, as was renal glutathione S-transferase 4 h after CEB administration. Renal ECOD activity was also diminished at 24 h and at 12 and 24 h in liver. Aminooxyacetic acid (AOAA) abrogated the nephrotoxicity, the renal GSH-enhancing effect, and decreased GCS of CEB alone. These findings provide further evidence for the importance of GSH conjugation as a significant pathway in CEB metabolism and the role of a reactive thiol in nephrotoxicity and altered renal GSH.  相似文献   
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