In this paper we discuss the use of cluster based computing as a basis for portable, heterogeneous parallel computing. We describe p4, a cluster based communications library which originates from Argonne National Laboratory, and our implementation of p4 on the transputer architecture. We present an extension to p4, \lightweight p4", which we designed for use in our research into automatic progr...

The packaging of genomic RNA in members of the Cystoviridae is performed by P4, a hexameric protein with NTPase activity. Across family members such as Phi6, Phi8 and Phi13, the P4 proteins show low levels of sequence identity, but presumably have similar atomic structures. Initial structure-determination efforts for P4 from Phi6 and Phi8 were hampered by difficulties in obtaining crystals that...

This article focuses on bacteriophage P4 as a potential peptide display phage by exploring the possibility of using the P4 capsid decoration component, Psu, as a peptide carrier protein. Psu is non-essential for P4 growth but it enhances the stability of the P4 capsid by binding to its exterior. We have constructed a unique SacI cloning site in the beginning of the psu gene. This site changes t...

Previously, we demonstrated that progesterone (P4) at physiologic levels (5-500 nM) inhibited proliferation in cultured rat aortic smooth muscle cells (RASMCs) through a P4 receptor (PR)-dependent pathway. We also showed that P4-induced cell cycle arrest in RASMCs occurs when the cyclin-CDK2 system is inhibited just as p21cip1 and p27kip1 protein levels are augmented. In the present study, we f...

Previously, we showed that progesterone (P4) inhibits proliferation and migration of rat aortic smooth muscle cells (RASMCs). The P4-induced migration inhibition in RASMCs resulted from suppression of the Ras homolog gene family, member A (RhoA) activity mediated by cSrc activation. We also observed that P4 increased the formation of p27-RhoA complex in RASMCs. The aim of this study was to furt...

Progesterone (P4) and estradiol (E2) modulate neurogenesis and synaptic remodeling in the hippocampus during the rat estrous cycle and in response to deafferenting lesions, but little is known about the steroidal regulation of hippocampal progesterone receptors associated with these processes. We examined the neuronal expression of progesterone receptor membrane component-1 (Pgrmc1) and the cla...

Progesterone (P4) promotes cell proliferation in several types of cancer, including brain tumors such as astrocytomas, the most common and aggressive primary intracerebral neoplasm in humans. In this work, we studied the effects of P4 and its intracellular receptor antagonist, RU486, on growth and infiltration of U373 cells derived from a human astrocytoma grade III, implanted in the motor cort...

DNA molecules isolated from tailless phage particles (capsids) of bacteriophage P4 virl del10 are known to be knotted. We have found by electron microscopy that 80% of DNA molecules isolated from intact phage particles of P4 virl del10 also contained knots. This observation indicates that the predominant form of P4 virl del10 DNA within the intact phage particle is either knotted or in a config...

Ovarian hormones influence memory formation by eliciting changes in neural activity. The effects of various concentrations of progesterone (P4) on synaptic transmission and plasticity associated with long-term potentiation (LTP) and long-term depression (LTD) were studied using in vitro hippocampal slices. Extracellular studies show that the highest concentration of P4 tested (10(-6) M) decreas...

The breast cancer resistance protein (BCRP) is abundant in the placenta and protects the fetus by limiting placental drug penetration. We hypothesize that pregnancyspecific hormones regulate BCRP expression. Hence, we examined the effects of progesterone (P4) and 17β-estradiol (E2) on BCRP expression in the human placental BeWo cells. P4 and E2 significantly increased and decreased BCRP protein...