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This article describes and evaluates an approach to create and/or improve tactical agents through direct human interaction in real time through a force-feedback haptic device. This concept takes advantage of a force-feedback joystick to enhance motor skill and decision-making transfer from the human to the agent in real time. Haptic devices have been shown to have high bandwidth and sensitivity. Experiments are described for this new approach, named Instructional Learning. It is used both as a way to build agents from scratch as well as to improve and/or correct agents built through other means. The approach is evaluated through experiments that involve three applications of increasing complexity – chasing a fleer (Chaser), shepherding a flock of sheep into a pen (Sheep), and driving a virtual automobile (Car) through a simulated road network. The results indicate that in some instances, instructional learning can successfully create agents under some circumstances. However, instructional learning failed to build and/or improve agents in other instances. The Instructional Learning approach, the experiments, and their results are described and extensively discussed.

Abstract Background The Runt-related transcription factor Runx2 is essential for bone development but is also implicated in progression of several cancers of breast, prostate and bone, where it activates cancer-related genes and promotes invasive properties. The transforming growth factor β (TGF-β) family member bone morphogenetic protein-3B (BMP-3B/GDF10) is regarded as a tumor growth inhibitor and a gene silenced in lung cancers; however the regulatory mechanisms leading to its silencing have not been identified. Results Here we show that Runx2 is highly expressed in lung cancer cells and downregulates BMP-3B. This inverse relationship between Runx2 and BMP-3B expression is further supported by increased expression of BMP-3B in mesenchymal cells from Runx2 deficient mice. The ectopic expression of Runx2, but not DNA binding mutant Runx2, in normal lung fibroblast cells and lung cancer cells resulted in suppression of BMP-3B levels. The chromatin immunoprecipitation studies identified that the mechanism of Runx2-mediated suppression of BMP-3B is due to the recruitment of Runx2 and histone H3K9-specific methyltransferase Suv39h1 to BMP-3B proximal promoter and a concomitant increase in histone methylation (H3K9) status. The knockdown of Runx2 in H1299 cells resulted in decreased histone H3K9 methylation on BMP-3B promoter and increased BMP-3B expression levels. Furthermore, co-immunoprecipitation studies showed a direct interaction of Runx2 and Suv39h1 proteins. Phenotypically, Runx2 overexpression in H1299 cells increased wound healing response to TGFβ treatment. Conclusions Our studies identified BMP-3B as a new Runx2 target gene and revealed a novel function of Runx2 in silencing of BMP-3B in lung cancers. Our results suggest that Runx2 is a potential therapeutic target to block tumor suppressor gene silencing in lung cancer cells.

In this study, we compared the incidence of fetomaternal hemorrhage between patients with threatened abortion and a control population of similar gestational age. The study population comprised pregnant patients at less than 20 weeks' gestation who presented to our emergency room with a history of vaginal bleeding without cervical dilatation or passage of tissue. The control population consisted of women presenting for elective pregnancy termination; they were excluded from the study if they gave a history of any antepartum bleeding. The amount of fetomaternal hemorrhage was evaluated using the Kleihauer-Betke acid elution assay. A positive result in our laboratory, as determined by a nonpregnant control group, was a value of 0.07% or more fetal cells. Using this criterion, 11% of the study population had a positive Kleihauer-Betke test, compared with 4% in the pregnant control group. Rho(D) immunoglobulin may be indicated in Rho(D)-negative patients who present with threatened abortion.

Twenty children (twenty hips) with spastic cerebral palsy underwent femoral varus-derotation osteotomy for which the principal indication was inadequate coverage of the femoral head. Other infrequent indications included pain, valgus angulation of the femoral neck, and dislocation of the hip. The age at surgery ranged from four to fifteen years. Each child had muscle releases before the osteotomy was done. At follow-up, at least seven years later, the femoral head in twenty hips was well centered. Four hips remained subluxated but were less subluxated than before the osteotomy. One hip remained dislocated. The center-edge angle averaged -8 degrees preoperatively and +17 degrees at follow-up. The neck-shaft angle averaged 155 degrees preoperatively, 114 degrees immediately post-operatively, and 125 degrees at follow-up. Femoral varus-derotation osteotomy, when combined with muscle releases, can allow children with spastic cerebral palsy to maintain their ambulatory status and may decrease pain about the hip.

The role of cytoskeletal structure in the alteration of cell shape, multinucleation, and intracellular transport of human prostatic carcinoma cells DU 145 was investigated by light microscopy, scanning and transmission electron microscopy, and by immunofluorescence microscopy. It was confirmed that alterations in cell shape and surface topography, multinucleation, and intracellular transport of these cultured cells were regulated by a microfilament system composed of actin. The presence of prekeratin confirmed the epithelial nature of these cells. It was noted for the first time that these cells were highly motile and contained fewer microtubules, a moderate amount of intermediate filaments, and a large amount of microfilaments. "Displastic" cells were quite common in long-term culture. DU 145 cells are excellent in vitro models for further research on human prostatic cancer cells.