We studied the effect of a bayesian pharmacokinetic dosing program on the outcome of aminoglycoside therapy in patients with clinical infections. Patients were randomized to a control (dosing based on physician choice; n = 75) or experimental group (dosing based on the bayesian program; n = 72). Both groups used serum aminoglycoside concentration data when making dosing decisions. Improved response rates were seen in the experimental (60%; 42/68) compared with the control group (48%; 36/68). A higher, but not statistically significant, incidence of toxicity was found in the control (7/75; 9.7%) versus the experimental group (4/72; 5.1%). Mean length of total hospital stay was significantly longer for patients in the control group (20.3 days) compared with the experimental group (16.0 days) (p = 0.028). The variables from multivariate analysis with a significant impact on length of stay were patient group and length of aminoglycoside therapy. On the basis of a reduced length of stay, a potential cost savings of $1311 per patient can be achieved.

No abstract

But why are some leaves simple and round and others complicated and curly? Hay and Tsiantis analyze how genetic networks enable one plant, Arabidopsis thaliana, to have simple undissected leaves, and a closely related plant, Cardamine hirsute, to have complex dissected leaves. Both plants express the homeobox protein KNOX, which functions as a transcription factor and affects leaf development. Both also express AS1 proteins that repress KNOX expression. The difference lies in the territory: KNOX protein confined to the shoot apical meristem results in simple leaves, whereas KNOX protein expressed in later leaf primordia results in complex leaves. The promoter sequences upstream of the KNOX coding region are critical for determining pattern of expression and hence the shape of the leaf. Although the topology of the genetic network is unchanged, in terms of which gene represses which effector, the morphological outcome is altered by changing the expression domain of the repressor.-PJH

No abstract

No abstract