Leukocyte trafficking in alveoli and airway passages

Many pulmonary diseases preferentially affect the large airways or the alveoli. Although the mechanisms are often particular to each disease process, site-specific differences in leukocyte trafficking and the regulation of inflammation also occur. Differences in the process of margination, sequestration, adhesion, and migration occur that can be attributed to differences in anatomy, hemodynamics, and the expression of proteins. The large airways are nourished by the bronchial circulation, whereas the pulmonary circulation feeds the distal lung parenchyma. The presence of different cell types in large airways from those in alveoli might contribute to site-specific differences in the molecular regulation of the inflammatory process

Single pi+ Electroproduction on the Proton in the First and Second Resonance Regions at 0.25GeV^2 < Q^2 < 0.65GeV^2 Using CLAS

The ep -> e'pi^+n reaction was studied in the first and second nucleon resonance regions in the 0.25 GeV^2 < Q^2 < 0.65 GeV^2 range using the CLAS detector at Thomas Jefferson National Accelerator Facility. For the first time the absolute cross sections were measured covering nearly the full angular range in the hadronic center-of-mass frame. The structure functions sigma_TL, sigma_TT and the linear combination sigma_T+epsilon*sigma_L were extracted by fitting the phi-dependence of the measured cross sections, and were compared to the MAID and Sato-Lee models.Comment: Accepted for publication in PR

Hyporesponsiveness to aerosolized but not to infused methacholine in cigarette-smoking dogs.

Abstract Seven beagles were exposed via a tracheostomy to smoke from 10 cigarettes/day, 5 days/wk for 10 months; 2 other dogs were exposed for 6 months only. Four dogs served as sham-exposed control animals. Mucus was collected 2 times/wk prior to and during the exposure period by resting a cytology brush on the lower trachea for 2 to 5 min. At least once prior to and as often as 3 times during exposure, transpulmonary pressure and flow were monitored under anesthesia to determine resistance RL. Two airway responses to methacholine were determined: the infusion response delta Ri, the increment in RL 4 to 6 min after infusion of 4 micrograms/kg/min, and the aerosol response delta Ra, the increment in RL 2 min after aerosolization of 2 mg/ml, the highest common dose reached. Eight of 9 smoking dogs developed persistent mucus hypersecretion. In 5 dogs, tracheal mucus flux increased 5- to 10-fold; in 3 dogs, the increase was 2 to 3 times that of control animals. One of the sham-exposed dogs developed moderate hypersecretion. After 10 months of smoke exposure, delta Ri increased to 2.24 times that of the initial value (+/- 0.47 SE) (n = 7, p less than 0.05), whereas delta Ra decreased to 0.28 times that of the control value (+/- 0.21 SE) (n = 6, p less than 0.02). The difference between aerosol and infusion response, delta Rai = delta Ra - delta Ri, is an index of relative hyporesponsiveness to methacholine aerosol.(ABSTRACT TRUNCATED AT 250 WORDS