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This study evaluated whether formaldehyde, at concentrations similar to those found in the indoor environment, could produce adverse effects on the lower airway of 15 asthmatic persons with documented bronchial hyperresponsiveness who were exposed for 90 min in a climate chamber to clean air containing formaldehyde vapor at levels of 0.85 mg/m3, 0.12 mg/m3, and 0.008 mg/m3. No significant changes in forced expiratory volume in 1 sec (FEV1), airway resistance (Raw), specific airway resistance (SRaw), and flow-volume curves could be detected during formaldehyde exposure. Furthermore, histamine challenge tests performed immediately after formaldehyde exposure showed no evidence of changes in bronchial reactivity. No late reactions were registered during the first 14-16 hr after exposure. The results suggest that residential levels of formaldehyde are of minor importance in the emergence of pulmonary symptoms. Discrepancies between the present study and previous data may be due to differences in environmental conditions.  相似文献   
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Background

This analysis evaluated effects of quetiapine XR maintenance treatment on functioning and sleep in patients with GAD.

Methods

Analysis of patient-reported data from a randomized-withdrawal, double-blind, placebo-controlled study of quetiapine XR monotherapy in GAD. Following open-label run-in (4–8 weeks) and a 12–18-week stabilization phase (quetiapine XR 50, 150, or 300 mg/day), eligible patients were randomized to continue on quetiapine XR or receive placebo for up to 52 weeks. Primary variable was time to an anxiety event. Secondary variables included the Sheehan Disability Scale (SDS) and Pittsburgh Sleep Quality Index (PSQI).

Results

In total, 432 patients were randomized (quetiapine XR, N=216; placebo, N=216). The risk of an anxiety event was significantly reduced for quetiapine XR vs. placebo (HR 0.19; 95% CI 0.12, 0.31; p<0.001). Quetiapine XR was more effective than placebo at maintaining SDS total scores (LSM change: −0.19 vs. 1.01; p=0.017) and non-work-related SDS domain score ‘family life/home responsibilities’ (−0.13 vs. 0.32; p=0.011), but not ‘social life’ (0.05 vs. 0.34; p=0.114). Quetiapine XR was more effective than placebo at maintaining the work-related SDS domain score ‘days lost’ (−0.05 vs. 0.11; p=0.027), but not ‘work/school’ (−0.10 vs. 0.29; p=0.051) or ‘days underproductive’ (0.06 vs. 0.13; p=0.619). PSQI global scores were reduced from randomization with quetiapine XR vs. placebo (0.39 vs. 1.60; p<0.001).

Limitations

Lack of active-comparator arm, exclusion of patients with comorbid depression.

Conclusions

In patients with GAD, long-term treatment with quetiapine XR (50–300 mg/day) monotherapy was effective at maintaining improvements in functioning and sleep quality.  相似文献   
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Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a hereditary cardiac condition associated with ventricular arrhythmias, heart failure, and sudden death. The most frequent ARVC genes encode desmosomal proteins of which mutations in desmoglein‐2 (DSG2), account for 10%–20% of cases. This study aimed to investigate how DSG2 mutations contribute to the pathogenesis of ARVC. Initial mutation analysis of DSG2 in 71 probands identified the first family reported with recessively inherited ARVC due to a missense mutation. In addition, three recognized DSG2 mutations were identified in 12 families. These results and further mutation analyses of four additional desmosomal genes indicated that ARVC caused by DSG2 mutations is often transmitted by recessive or digenic inheritance. Because desmosomal proteins are also expressed in skin tissue, keratinocytes served as a cell model to investigate DSG2 protein expression by Western blotting, 2D‐PAGE, and liquid chromatography–mass spectrometry. The results showed that heterozygous mutation carriers expressed both mutated and wild‐type DSG2 proteins. These findings were consistent with the results obtained by immunohistochemistry of endomyocardial biopsies and epidermal tissue of mutation carriers, which indicated a normal cellular distribution of DSG2. The results suggested a dominant‐negative effect of the mutated DSG2 proteins because they were incorporated into the desmosomes.  相似文献   
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BackgroundAllergic rhinitis (AR), allergic conjunctivitis (AC), and asthma composing multiple phenotypes and improved understanding of these phenotypes and their respective risk factors are needed.ObjectivesThe objective of this study was to define the prevalence of AR, AC, and asthma and their association with allergen‐specific immunoglobulin E (sIgE) sensitization in a large cohort of blood donors and identify risk factors.MethodsFrom the nationwide population‐based Danish Blood Donor Study, 52,976 participants completed an electronic questionnaire including AR, AC, asthma, allergic predisposition, and childhood residence. Of these, 25,257 were additionally tested for sIgE to inhalation allergens (Phadiatop).ResultsThe prevalence of sIgE sensitization, AR, AC, and asthma was 30%, 19%, 15%, and 9%, respectively. The youngest birth cohorts had the highest prevalence of sIgE sensitization and symptoms of asthma, AR, and AC, and for asthma, they apparently experienced symptoms at an earlier age. The sIgE sensitization was positively associated with male sex. The sIgE seroprevalence was higher in participants with both AR and AC (ARC) than in participants with either AR or AC. Allergic predisposition and sIgE sensitization increased the risk of the diseases, while farm upbringing was associated with reduced prevalence of ARC, however, only in sIgE sensitized participants.ConclusionBirth year, childhood residence, sIgE sensitization, and allergic predisposition were associated with asthma, AR, and AC prevalence. Individuals with self‐reported ARC represent a primarily sIgE‐positive phenotype, while those with either AR or AC represent more diverse phenotypes.  相似文献   
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