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61.

Background

Protease-Activated Receptor-2 (PAR-2), a G protein coupled receptor activated by serine proteases, is widely expressed in humans and is involved in inflammation. PAR-2 activation in the airways plays an important role in the development of allergic airway inflammation. PAR-2 expression is known to be upregulated in the epithelium of asthmatic subjects, but its expression on immune and inflammatory cells in patients with asthma has not been studied.

Methods

We recruited 12 severe and 24 mild/moderate asthmatics from the University of Alberta Hospital Asthma Clinics and collected baseline demographic information, medication use and parameters of asthma severity. PAR-2 expression on blood inflammatory cells was analyzed by flow cytometry.

Results

Subjects with severe asthma had higher PAR-2 expression on CD14++CD16+ monocytes (intermediate monocytes) and also higher percentage of CD14++CD16+PAR-2+ monocytes (intermediate monocytes expressing PAR-2) in blood compared to subjects with mild/moderate asthma. Receiver operating characteristics (ROC) curve analysis showed that the percent of CD14++CD16+PAR-2+ in peripheral blood was able to discriminate between patients with severe and those with mild/moderate asthma with high sensitivity and specificity. In addition, among the whole populations, subjects with a history of asthma exacerbations over the last year had higher percent of CD14++CD16+ PAR-2+ cells in peripheral blood compared to subjects without exacerbations.

Conclusions

PAR-2 expression is increased on CD14++CD16+ monocytes in the peripheral blood of subjects with severe asthma and may be a biomarker of asthma severity. Our data suggest that PAR-2 -mediated activation of CD14++CD16+ monocytes may play a role in the pathogenesis of severe asthma.  相似文献   
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The western arctic population of King Eiders (Somateria spectabilis) has declined by >50% in recent years. A health assessment was conducted for adult King Eiders breeding on the north slope of Alaska, USA, to evaluate body condition (n=90, 2002-2006) and baseline biochemical and hematologic values (n=20-30, 2005-2006). Body condition for males and females was excellent. Total protein, calcium, alkaline phosphatase, amylase, and globulin were significantly higher in females than in males, likely because of differences in reproductive physiology. These baseline health data can be used to promote conservation of King Eiders and other closely related species of concern.  相似文献   
64.
(+)-ABA content and lipid deposition in interior spruce somatic embryos   总被引:1,自引:0,他引:1  
Summary Interior spruce (Picea glauca engelmannii complex) somatic embryos grown on 48 μmol (±)-ABA per L over a period of 42 d without transfer underwent precocious germination by 49 d. Those transferred at 28 d to fresh medium with 48 μmol (±)-ABA continued embryo development until harvested at 56 d; the transfer at 28 d resulted in an increase in embryo lipid content after 42 d. Somatic embryos grown under this condition contained 181.4±41.2, 116.0±42.4, and 91.8±33.6 ng (+)-ABA per mg of lyophilized tissue at 42, 49, and 56 d, respectively. By comparison, embryos grown without the transfer at 28 d had 86.8±25.4 ng (+)-ABA per mg of lyophilized tissue at 42 d, just prior to precocious germination. After 3 weeks’ storage in a drying chamber under high humidity, the (+)-ABA content of 56-d-old transferred embryos decreased to 15.4 ± 4.4 ng (+)-ABA per mg of lyophilized tissue. The increased lipid content resulting from embryo transfer and the reduction in internal (+)-ABA content during storage are factors which will contribute to improved conversion of somatic embryos to plantlets.  相似文献   
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The complete sequencing and annotation of the 181.7-kb Bacillus anthracis virulence plasmid pXO1 predicted 143 genes but could only assign putative functions to 45. Hybridization assays, PCR amplification, and DNA sequencing were used to determine whether pXO1 open reading frame (ORF) sequences were present in other bacilli and more distantly related bacterial genera. Eighteen Bacillus species isolates and four other bacterial species were tested for the presence of 106 pXO1 ORFs. Three ORFs were conserved in most of the bacteria tested. Many of the pXO1 ORFs were detected in closely related Bacillus species, and some were detected only in B. anthracis isolates. Three isolates, Bacillus cereus D-17, B. cereus 43881, and Bacillus thuringiensis 33679, contained sequences that were similar to more than one-half of the pXO1 ORF sequences examined. The majority of the DNA fragments that were amplified by PCR from these organisms had DNA sequences between 80 and 98% similar to that of pXO1. Pulsed-field gel electrophoresis revealed large potential plasmids present in both B. cereus 43881 (341 kb) and B. thuringiensis ATCC 33679 (327 kb) that hybridized with a DNA probe composed of six pXO1 ORFs.  相似文献   
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69.
The optimization of compounds from the 3-amido-4-anilinoquinolines series of CSF-1R kinase inhibitors is described. The series has excellent activity and kinase selectivity. Excellent physical properties and rodent PK profiles were achieved through the introduction of cyclic amines at the quinoline 6-position. Compounds with good activity in a mouse PD model measuring inhibition of pCSF-1R were identified.  相似文献   
70.
As a reported agonist,11C-CUMI-101 is believed to selectively bind the G-protein-coupled state of the serotonin-1A (5-HT1A) receptor, thereby providing a measure of the active subset of all 5-HT1A receptors in brain. Although 11C-CUMI-101 has been successfully used to quantify 5-HT1A receptors in human and monkey brain, its radiation exposure has not previously been reported. The purpose of this study was to calculate the radiation exposure to organs of the body based on serial whole-body imaging with positron emission tomography (PET) in human subjects.

Methods

Nine healthy volunteers were injected with 428±84 MBq (mean ± SD) 11C-CUMI-101 and then imaged with a PET-only device for two hours from head to mid-thigh. Eleven source organs (brain, heart, liver, pancreas, stomach, spleen, lungs, kidneys, lumbar spine L1-5, thyroid, and urinary bladder) were identified on whole body images and used to calculate radiation doses using the software program OLINDA/EXM 1.1. To confirm that we had correctly identified the pancreas, a tenth subject was imaged on a PET/CT device.

Results

Brain had high uptake (∼11% of injected activity (IA)) at 10 min. Although liver had the highest uptake (∼35% IA at 120 min), excretion of this activity was not visible in gall bladder or intestine during the scanning session. Organs which received the highest doses (microSv/MBq) were pancreas (32.0), liver (18.4), and spleen (14.5). The effective dose of 11C-CUMI-101 was 5.3±0.5 microSv/MBq.

Conclusion

The peak brain uptake (∼11% IA) of 11C-CUMI-101 is the highest among more than twenty 11C-labeled ligands reported in the literature and provides good counting statistics from relatively low injected activities. Similar to that of other 11C-labeled ligands for brain imaging, the effective dose of 11C-CUMI-101 is 5.3±0.5 microSv/MBq, a value that can now be used to estimate the radiation risks in future research studies.  相似文献   
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