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We investigated the effect the loss of the CAT-2 gene (CAT-2-/-) has on lung resistance ([R.sub.L]) and tracheal isometric tension. The [R.sub.L] of CAT-2-/- mice at a maximal dose of acetylcholine (ACh) was decreased by 33.66% (P = 0.05, n = 8) compared with that of C57BL/6 (B6) mice. The isometric tension of tracheal rings from CAT-2-/- mice showed a significant decrease in carbachol (CCh)-induced force generation (33.01%, P < 0.05, n = 8) compared with controls. The isoproterenol- or the sodium nitroprusside-induced relaxation was not affected in tracheal rings from CAT-2-/- mice. The activity of iNOS and arginase in lung tissue lysates of CAT-2-/- mice was indistinguishable from that of B6 mice. Furthermore, the expression of phospholipase-C[beta] (PLC-[beta]) and phosphatidylinositol-(4)-phosphate-5-kinase-[gamma] (PIP-5K-[gamma]) was examined in the lung tissue of CAT-2-/- and B6 mice. The expression of PIP-5K-[gamma] but not PLC-[beta] was significantly reduced in CAT-2-/- compared with B6 mice. The reduced airway smooth muscle (ASM) contractility to CCh seen in the CAT-2-/- tracheal rings was completely reversed by pretreating the rings with 100 [micro]M spermine. This increase in the CAT-2-/- tracheal ring contraction upon spermine pretreatment correlated with a recovery of the expression of PIP-5K-[gamma]. Our data indicates that CAT-2 exerts control over ASM force development through a spermine-dependent pathway that directly correlates with the expression level of PIP-5K-[gamma] in the lung. lung resistance; tracheal isometric tension

Contractors are required by the Michigan Department of Transportation (MDOT) to submit a progress schedule identifying the controlling path of activities for a construction project. During the 2000 construction season, MDOT allowed contractors to submit a progress schedule with overlapping or concurrent controlling operations. Prior to this, only one activity at a time could be controlling on the progress schedule. This paper reports on the results of a research project where the focus was to examine the accuracy of the progress schedules, which only list controlling items. Eight construction projects were studied and a determination of progress schedule accuracy was made. This was done to determine if there was an increase in accuracy of the schedules when concurrent controlling operations were used. Included in the eight projects were four without concurrent controlling activities and four with concurrent controlling activities. A comparison based upon similar projects with and without concurrent activities was made. Additionally, 22 projects were analyzed, all without concurrent controlling activities, to determine the accuracy of progress schedules for two types of projects. The comparison revealed that, in three of the four cases, the accuracy of progress schedules increased with the allowance of concurrent controlling activities. The 22 projects revealed that the accuracy of progress schedules varied considerably. It was also determined that contractors overestimated the duration of activities included in progress schedules. CE Database subject headings: Highway construction; Contractors; Scheduling; Construction management.

We investigated the effect the loss of the CAT-2 gene (CAT-2—/—) has on lung resistance (RL) and tracheal isometric tension. The RL of CAT-2—/— mice at a maximal dose of acetyicholine (ACh) was decreased by 33.66% (P = 0.05, n = 8) compared with that of C57BL/6 (B6) mice. The isometric tension of tracheal rings from CAT-2—/— mice showed a significant decrease in carbachol (CCh)-induced force generation (33.01%, P < 0.05, n = 8) compared with controls. The isoproterenol- or the sodium nitroprusside-induced relaxation was not affected in tracheal rings from CAT-2—/— mice. The activity of iNOS and arginase in lung tissue lysates of CAT-2—/— mice was indistinguishable from that of B6 mice. Furthermore, the expression of phospholipase-Cβ (PLC-β) and phosphatidylinositol-(4)-phosphate-5-kinase-γ (PIP-5K-γ) was examined in the lung tissue of CAT-2—/— and B6 mice. The expression of PIP-5K-γ but not PLC-β was significantly reduced in CAT-2—/— compared with B6 mice. The reduced airway smooth muscle (ASM) contractility to CCh seen in the CAT-2—/— tracheal rings was completely reversed by pretreating the rings with 100 μM spermine. This increase in the CAT-2—/— tracheal ring contraction upon spermine pretreatment correlated with a recovery of the expres- sion of PIP-5K-γ. Our data indicates that CAT-2 exerts control over ASM force development through a spermine-dependent pathway that directly correlates with the expression level of PIP-5K-γ in the lung. [ABSTRACT FROM AUTHOR]