The treatment for patients with chronic obstructive pulmonary disease (COPD) usually involves a combination of anti-inflammatory and bronchodilatory drugs. We recently found that mepenzolate bromide (1) and its derivative, 3-(2-hydroxy-2, 2-diphenylacetoxy)-1-(3-phenoxypropyl)-1-azoniabicyclo[2.2.2]octane bromide (5), have both anti-inflammatory and bronchodilatory activities. We chemically modified 5 with a view to obtain derivatives with both anti-inflammatory and longer-lasting bronchodilatory activities. Among the synthesized compounds, (R)-(–)-12 ((R)-3-(2-hydroxy-2,2-diphenylacetoxy)-1-(3-phenylpropyl)-1-azoniabicyclo[2.2.2]octane bromide) showed the highest affinity in vitro for the human muscarinic M3 receptor (hM3R). Compared to 1 and 5, (R)-(–)-12 exhibited longer-lasting bronchodilatory activity and equivalent anti-inflammatory effect in mice. The long-term intratracheal administration of (R)-(–)-12 suppressed porcine pancreatic elastase-induced pulmonary emphysema in mice, whereas the same procedure with a long-acting muscarinic antagonist used clinically (tiotropium bromide) did not. These results suggest that (R)-(–)-12 might be therapeutically beneficial for use with COPD patients given the improved effects seen against both inflammatory pulmonary emphysema and airflow limitation in this animal model. 相似文献
Forests are experiencing increasing pressure from human activities, which is leading to rapid deforestation and loss of ecosystem
services. Although deforestation occurs for a wide range of reasons, one important reason is that landowners lack a long-term
management view. I suggest that both economic incentives and social norms will work differently to reduce landowners’ motivation
to deforest and to help landowners identify the long-term benefits that will be obtained by sacrificing short-term gain. 相似文献
The notion that there is a 'social brain' in humans specialized for social interactions has received considerable support from brain imaging and, to a lesser extent, from lesion studies. Specific roles for the various components of the social brain are beginning to emerge. For example, the amygdala attaches emotional value to faces, enabling us to recognize expressions such as fear and trustworthiness, while the posterior superior temporal sulcus predicts the end point of the complex trajectories created when agents act upon the world. It has proved more difficult to assign a role to medial prefrontal cortex, which is consistently activated when people think about mental states. I suggest that this region may have a special role in the second-order representations needed for communicative acts when we have to represent someone else's representation of our own mental state. These cognitive processes are not specifically social, since they can be applied in other domains. However, these cognitive processes have been driven to ever higher levels of sophistication by the complexities of social interaction. 相似文献
An α-amylase from Aspergillus oryzae, Taka-amylase A (TAA), was cleaved into peptide fragments by an acid protease. Inactivation of TAA was greatly retarded by the addition of α-cyclodextrin or Ca2+. TAA peptide fragments were separated into two groups having no and high affinity to the substrate, soluble starch. This separation was done by the forced affinity chromatography method by a column of epichlorohydrin cross-linked soluble starch gel. Three peptides were isolated from the high-affinity fragments, purified by the ODS-120T column, and their amino acids were sequenced. Peptides I, II, and III originated from α2-helix, α3-helix, and β2-sheet, respectively, and all of these were located in the (β/α)8 barrel of the main domain of TAA molecule. A stereo graphic view showed that Peptides I–III were at the cleft near the catalytic site. Occurrence of a Trp residue in all three peptides strongly suggested that Trp was very important in the binding of TAA to the substrate, soluble starch. 相似文献
1. 1. This study was conducted to investigate the effects of forced vital capacity on breathing pattern and subjective responses to inspiratory resistance.
2. 2. The subjects were divided into two groups according to their %FVC [large (L) and small (S) group; five subjects in each].
3. 3. Added inspiratory resistances were 0.6 (control), 1.5 (R1), 2.5 (R2), 3.1 (R3) cmH2O · 1−1 · s.
4. 4. Breathing pattern was analyzed by personal computer during rest and exercise with bicycle ergometer.
5. 5. The degree of sensation of breathing difficulty was expressed in SNS reported in our previous study.
6. 6. SNS in S group increased with resistance while no tendency was observed in L group. SNS in S group was significantly greater than that in L group at R3 condition.
7. 7. The breathing pattern of S group was characterized in smaller tidal volume and faster respiratory frequency compared to those of L group with no resistive load.
8. 8. However, outstanding changes in breathing pattern were observed in S group with longer inspiratory time and lower mean inspiratory flow rate when resistive loads were added, which led to increased tidal volume and decreased respiratory frequency.