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1.
D-cycloserine augmented exposure therapy for obsessive-compulsive disorder.   总被引:1,自引:1,他引:0  
BACKGROUND: D-cycloserine (DCS), a glutamatergic partial N-methyl-d-aspartate (NMDA) agonist, can facilitate extinction learning related to cued fear in animals and humans. We predicted that DCS would accelerate obsession-related distress reduction in patients with obsessive-compulsive disorder (OCD) undergoing extinction-based exposure therapy. METHODS: We administered DCS (125 mg) or placebo in a double-blind fashion to individuals with OCD approximately 2 hours before each exposure session. RESULTS: D-cycloserine decreased both the number of exposure sessions required to achieve clinical milestones and the rate of therapy dropout. After four exposure sessions, patients in the DCS group reported significantly greater decreases in obsession-related distress compared with the placebo group; however, after additional sessions, the placebo group tended to catch up. CONCLUSIONS: D-cycloserine augmentation has the potential to increase the efficiency, palatability, and overall effectiveness of standard exposure therapy for OCD.  相似文献   
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Background: Antigen 5 is one of three major allergens in wasp venoms, but unlike phospholipase A(1) and hyaluronidase, both of which are enzymes, its biological function is unknown. The cDNA coding for this allergen has been isolated and used for recombinant expression. Thorough analysis of the expression product is essential in order to evaluate the usefulness for in vivo or in vitro application. Objective: In this study, folding variants of the recombinant major allergen Ves v 5 from Vespula vulgaris were immunologically and biochemically investigated in order to determine their possible applicability for diagnostic or therapeutic purposes. Method: The cDNA encoding Ves v 5 was cloned into the expression vector pSE420 which generates recombinant products lacking a tag sequence. After expression, inclusion bodies were purified, subsequently denatured and dialyzed against different solutions. The structural properties of soluble proteins were analyzed by size exclusion chromatography, non-reducing SDS-PAGE, native PAGE, N-terminal sequencing, proteolytic digestion and ion exchange chromatography. Immunological investigations were performed by using different monoclonal antibodies (mAbs) specific for Ves v 5 and IgE from patients allergic to wasp venom allergens. Results: After dialysis, soluble monomeric recombinant Ves v 5 was more than 95% pure in each case. Using different dialysis solutions, clearly distinguishable folding variants were obtained. In one case, the recombinant allergen was comparable with the natural counterpart in respect of migration in non-reducing SDS-PAGE, native PAGE and IgE reactivity. This variant reacted with two different Ves v 5-specific mAbs and produced a stable fragment after proteolytic digestion. Elution from a cation exchange chromatography column was achieved with 320 mM NaCl. In two other cases, folding variants exhibited a different migration behavior in SDS-PAGE and native PAGE compared with the natural allergen. Also, the mAb 1E11 recognized none of these variants since it presumably detected a conformational epitope. Moreover, the IgE reactivity was clearly reduced and proteolytic digestion effected almost complete degradation. These variants eluted from the cation exchange column with 400 mM NaCl. Conclusion: Defined folding strategies resulted in both soluble misfolded variants with reduced IgE reactivity, potentially suitable for immunotherapy, and natural-like folded variants for diagnosis.  相似文献   
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Suck R  Nandy A  Weber B  Stock M  Fiebig H  Cromwell O 《Allergy》2002,57(9):821-824
BACKGROUND: The availability of increasing numbers of purified natural and recombinant allergens offer the possibility for component-resolved characterization of IgE binding. To make use of this potential, fast and simple methods with high capacity have to be developed. METHODS: A laboratory multiscreen device was used in an innovative two-dimensional approach. In the first step, natural and recombinant allergens were immobilized onto the membrane using the sample chambers as application mask and, after blocking and rotating the membrane through 90 degrees, the same device was used to apply and incubate sera of allergic patients. Enzyme-linked immunoassay (ELISA) quantification of specific IgE was performed for purposes of comparison. RESULTS: Proteins were most efficiently bound onto nitrocellulose in 20 mM sodium hydroxide (NaOH). Up to 45 proteins or extracts could be investigated with a maximum of 45 sera in a single application, resulting in a resolution of 2,025 spots on one membrane with a size comparable to a standard Western blot. A high correlation for IgE-binding between natural and recombinant allergens was observed. Development of the membrane resulted in very evenly distributed square patterns. The results corresponded with the conventional ELISA measurements of specific IgE. CONCLUSIONS: The innovative usage of a standard incubation device for both application of proteins as well as screening of sera provides a simple high throughput method for the characterization of IgE binding to allergens. The results are important for component resolved diagnosis of allergy by means of fast monitoring of IgE- and IgG-reactivity spectra. Recombinant allergens may be used as targets for these purposes.  相似文献   
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BackgroundAsthma and chronic obstructive pulmonary disease (COPD) are airway diseases with similar clinical manifestations, despite differences in pathophysiology. Asthma-COPD overlap (ACO) is a condition characterized by overlapping clinical features of both diseases. There have been few reports regarding the prevalence of ACO in COPD and severe asthma cohorts. ACO is heterogeneous; patients can be classified on the basis of phenotype differences. This study was performed to analyze the prevalence of ACO in COPD and severe asthma cohorts. In addition, this study compared baseline characteristics among ACO patients according to phenotype.MethodsPatients with COPD were prospectively enrolled into the Korean COPD subgroup study (KOCOSS) cohort. Patients with severe asthma were prospectively enrolled into the Korean Severe Asthma Registry (KoSAR). ACO was defined in accordance with the updated Spanish criteria. In the COPD cohort, ACO was defined as bronchodilator response (BDR) ≥ 15% and ≥ 400 mL from baseline or blood eosinophil count (BEC) ≥ 300 cells/μL. In the severe asthma cohort, ACO was defined as age ≥ 35 years, smoking ≥ 10 pack-years, and post-bronchodilator forced expiratory volume in 1 s/forced vital capacity < 0.7. Patients with ACO were divided into four groups according to smoking history (threshold: 20 pack-years) and BEC (threshold: 300 cells/μL).ResultsThe prevalence of ACO significantly differed between the COPD and severe asthma cohorts (19.8% [365/1,839] vs. 12.5% [104/832], respectively; P < 0.001). The percentage of patients in each group was as follows: group A (light smoker with high BEC) – 9.1%; group B (light smoker with low BEC) – 3.7%; group C (moderate to heavy smoker with high BEC) – 73.8%; and group D (moderate to heavy smoker with low BEC) – 13.4%. Moderate to heavy smoker with high BEC group was oldest, and showed weak BDR response. Age, sex, BDR, comorbidities, and medications significantly differed among the four groups.ConclusionThe prevalence of ACO differed between COPD and severe asthma cohorts. ACO patients can be classified into four phenotype groups, such that each phenotype exhibits distinct characteristics.  相似文献   
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Journal of Gastroenterology - The overlap between functional dyspepsia (FD) and irritable bowel syndrome (IBS) is associated with more severe gastrointestinal (GI) symptoms and lower quality of...  相似文献   
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BACKGROUND: The BRAF(V600E) mutation, the most common genetic alteration reported in papillary thyroid carcinoma, has been associated with poor prognostic factors. AIM: To determine whether the presence of the BRAF(V600E) mutation is associated with poor prognosis in Korean patients with conventional papillary thyroid microcarcinoma (micro-PTC). PATIENTS AND METHODS: DNA was extracted from paraffin-embedded thyroid tumour specimens taken from 60 patients with conventional micro-PTC, as well as from nine patients with follicular variant papillary carcinoma, six with nodular hyperplasia, four with follicular carcinoma (including one with Hürthle cell carcinoma), four with follicular adenoma (including two with Hürthle cell adenoma) and one each with medullary carcinoma, poorly differentiated carcinoma and anaplastic carcinoma. The presence of the BRAF(V600E) mutation was determined by polymerase chain reaction (PCR) amplification of exon 15 followed by direct sequencing. RESULTS: The BRAF(V600E) mutation was detected in tumour samples from 31 of 60 conventional micro-PTC patients (52%), but was not detected in patients with other types of thyroid tumours. The age distribution, tumour size, extrathyroid extension, multifocality and staging did not differ significantly between patients with and without the BRAF(V600E) mutation. CONCLUSION: In Korean patients with conventional micro-PTC, the presence of the BRAF(V600E) mutation was not significantly associated with prognostic factors.  相似文献   
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