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Background

Sleep duration and quality have been associated with increased cardiovascular risk. However, large studies linking objectively measured sleep and subclinical atherosclerosis assessed in multiple vascular sites are lacking.

Objectives

The purpose of this study was to evaluate the association of actigraphy-measured sleep parameters with subclinical atherosclerosis in an asymptomatic middle-aged population, and investigate interactions among sleep, conventional risk factors, psychosocial factors, dietary habits, and inflammation.

Methods

Seven-day actigraphic recording was performed in 3,974 participants (age 45.8 ± 4.3 years; 62.6% men) from the PESA (Progression of Early Subclinical Atherosclerosis) study. Four groups were defined: very short sleep duration <6 h, short sleep duration 6 to 7 h, reference sleep duration 7 to 8 h, and long sleep duration >8 h. Sleep fragmentation index was defined as the sum of the movement index and fragmentation index. Carotid and femoral 3-dimensional vascular ultrasound and cardiac computed tomography were performed to quantify noncoronary atherosclerosis and coronary calcification.

Results

When adjusted for conventional risk factors, very short sleep duration was independently associated with a higher atherosclerotic burden with 3-dimensional vascular ultrasound compared to the reference group (odds ratio: 1.27; 95% confidence interval: 1.06 to 1.52; p = 0.008). Participants within the highest quintile of sleep fragmentation presented a higher prevalence of multiple affected noncoronary territories (odds ratio: 1.34; 95% confidence interval: 1.09 to 1.64; p = 0.006). No differences were observed regarding coronary artery calcification score in the different sleep groups.

Conclusions

Lower sleeping times and fragmented sleep are independently associated with an increased risk of subclinical multiterritory atherosclerosis. These results highlight the importance of healthy sleep habits for the prevention of cardiovascular disease.  相似文献   
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Brito FF  Mur P  Barber D  Lombardero M  Galindo PA  Gómez E  Borja J 《Allergy》2002,57(12):1191-1194
BACKGROUND: The family Dermestidae belongs to the order Coleoptera. Occupational allergy has been described in museum personnel. A 31-year-old male wool worker presenting rhinoconjunctivitis and asthma episodes probably linked to exposure to Dermestidae-infected wool was investigated. METHODS: Extracts prepared either from insect bodies or from dust from parasitized wool were used for skin prick testing (SPT), conjunctival and bronchial provocation tests and in vitro determinations. RESULTS: SPT and provocation tests were positive to both extracts. PEFR measurement demonstrated the association between the patient's symptoms and occupational exposure to Dermestidae. Specific IgE to both extracts was detected and immunoblotting revealed several protein bands from 5 to 200 kDa that were reactive to IgE from the patient's serum. CONCLUSIONS: Dermestidae exposure in wool workers when handling parasitized wool can be a cause of IgE-mediated rhinoconjunctivitis and asthma.  相似文献   
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BACKGROUND: Skin testing and sera measurements have verified the existence of tobacco specific IgE. However, the few published studies on this matter report conflicting results concerning their clinical significance. OBJECTIVE: To verify if a specific clinical allergenic response against tobacco might be possible in allergenic and nonallergenic bronchial diseases. METHODS: We performed a cross-sectional observational case-control analysis on 180 patients with asthma, chronic obstructive pulmonary disease (COPD), and bronchial carcinoma and controls who were randomly chosen. Skin prick tests and serum specific IgE to tobacco and related allergens, bronchial challenge with cigarettes and tobacco extract, patch tests with tobacco and nicotine, sodium dodecyl sulfate-polyacrylamide gel electrophoresis immunoblotting, and Enzyme AllergoSorbent Test (EAST) inhibition were performed. RESULTS: Twenty-eight patients had positive tobacco skin prick test results. The association among positive skin prick test results, IgE, and bronchial challenge was strong (P < .001). Tobacco sensitivity was higher in patients with pollen asthma than in patients with COPD and carcinoma and negative in patients with intrinsic asthma and controls. A positive bronchial challenge result was related to the length of habit (P < .001) and the tobacco index in patients who had stopped smoking (P < .001). Delayed bronchial and patch response was more common in patients with COPD (P < .001). Tobacco IgE response (EAST) was related to sensitivity to Lolium perenne (rye grass) pollen (P < .001) but not to other vegetables that belong to the Solanaceae family. EAST inhibition showed cross-reactivity between tobacco and Lolium pollen. CONCLUSIONS: Tobacco may be responsible for a specific IgE response. Patients with pollen asthma were those with more positive responses to tobacco due to cross-reactivity between Lolium and tobacco allergens.  相似文献   
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Background Context

Pedicle screws in spinal surgery have allowed greater biomechanical stability and higher fusion rates. However, malposition is very common and may cause neurologic, vascular, and visceral injuries and compromise mechanical stability.

Purpose

The purpose of this study was to compare the malposition rate between intraoperative computed tomography (CT) scan assisted-navigation and free-hand fluoroscopy-guided techniques for placement of pedicle screw instrumentation.

Study Design/Setting

This is a prospective, randomized, observational study.

Patient Sample

A total of 114 patients were included: 58 in the assisted surgery group and 56 in the free-hand fluoroscopy-guided surgery group.

Outcome Measures

Analysis of screw position was assessed using the Heary classification. Breach severity was defined according to the Gertzbein classification. Radiation doses were evaluated using thermoluminescent dosimeters, and estimates of effective and organ doses were made based on scan technical parameters.

Methods

Consecutive patients with degenerative disease, who underwent surgical procedures using the free-hand, or intraoperative navigation technique for placement of transpedicular instrumentation, were included in the study.

Results

Forty-four out of 625 implanted screws were malpositioned: 11 (3.6%) in the navigated surgery group and 33 (10.3%) in the free-hand group (p<.001). Screw position according to the Heary scale was Grade II (4 navigated surgery, 6 fluoroscopy guided), Grade III (3 navigated surgery, 11 fluoroscopy guided), Grade IV (4 navigated surgery, 16 fluoroscopy guided), and Grade V (1 fluoroscopy guided). There was only one symptomatic case in the conventional surgery group. Breach severity was seven Grade A and four Grade B in the navigated surgery group, and eight Grade A, 24 Grade B, and one Grade C in free-hand fluoroscopy-guided surgery group. Radiation received per patient was 5.8 mSv (4.8–7.3). The median dose received in the free-hand fluoroscopy group was 1?mGy (0.8–1.1). There was no detectable radiation level in the navigation-assisted surgery group, whereas the effective dose was 10 µGy in the free-hand fluoroscopy-guided surgery group.

Conclusions

Malposition rate, both symptomatic and asymptomatic, in spinal surgery is reduced when using CT-guided placement of transpedicular instrumentation compared with placement under fluoroscopic guidance, with radiation values within the safety limits for health. Larger studies are needed to determine risk-benefit in these patients.  相似文献   
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