Dissection of Microphage Activation Using T Cell Hybridoma Derived Lymphokines

Macrophage phenotype/function can be modulated by various T-cell lymphokines (LK). The alteration of macrophage phenotype is a result of LK concentration, duration of exposure, and the level of macrophage activation when obtained from in vivo sources through elicitation by either sterile irritants or immune cellular mechanisms. In order to dissect macrophage activation into discrete signals T cell hybridomas were constructed by fusing HAT sensitive BW5147 cells with nylon-wool purified, con A stimulated T cells. The resulting T cell hybrids were screened for their ability to: (a) protect macrophages from the cytopathic effect of Naegleria; (b) induce class II MHC gene product (Ia antigen) expression; (c) increase cytostasis and tumoricidal activity; and (d) alter ectoenzyme profiles on either resident or thioglycollate (TG) elicited macrophages. Two hybridomas (T-3 and T-9) were selected for further evaluation because of their activity patterns. Supernatants from T-3 and T-9 were compared with cloned Y-interferon (γ-IFN) for alteration of biological activities. Both T-3 and T-9 were able to protect resident macrophage cells from Naegleria but had no protective effect on TG-macrophages. T-9 supernatant had patterns of activity similar to γ-IFN while T-3 patterns were different. The addition of anti-Y-IFN removed T-9 cytostatic activity while not affecting T-3 induced activity. The LK inducing protection from the cytopathic effect of Naegleria lysate is not γ-IFN but another molecular moiety. It was also shown that γ-IFN does not protect TG-macrophages from the destructive effects of adenylate cyclase produced by Bordetella pertussis. We conclude that activation of macrophages for the destruction of tumor cells and activation for protection against amoeba and bacteria occur via different biological pathways. Furthermore, we have proposed an association between the cell cycle and the responsiveness of resident and TG-elicited macrophages to specific LK

Trait Mindfulness and Adolescent Depression: Emotional Awareness and Emotion Regulation as Mediators

In adults, trait mindfulness has been linked to lower rates of depression. However, there is little evidence for this relationship in adolescents. The goal of this study was to examine whether trait mindfulness was related to adolescent depression and what the underlying mechanisms of this relation might be, specifically looking at emotional awareness and emotion regulation. Mindfulness, depression, emotional awareness, and emotion regulation measures were completed by adolescent males. The results showed a robust, negative relationship between trait mindfulness and adolescent depression that was not explained by emotion regulation or emotional awareness. Trait mindfulness moderated the relationship between cognitive reappraisal and depression. These results suggest that trait mindfulness could be important in preventing depression in adolescent males. Future research should focus more fully on measuring trait mindfulness and its relations with other constructs, as well as reproducing this study with multiple time points and females

Heuristics Associated with Forecasting Chaotic Events: A Rare Cognitive Ability

Chaos is a mathematical phenomenon in which seemingly random events are actually predictable by simple deterministic equations. Chaos has been identified in numerous situations requiring humans’ situation awareness, sense-making, and control. The management of chaos could be a rare skill, however, and the heuristics for doing so are not well understood. These hiatuses thus motivated a new theoretical issue in ergonomics science concerning the distribution of this ability across different chaotic attractors and some of the heuristics that might be used to forecast events. Untrained undergraduates (N = 147) forecasted number series from four chaotic attractors of varying levels of computational complexity. Performance was measured as the correlation between forecasted numbers and real numbers. Participants’ performance varied by type of attractor and whether the forecasts were made for one to four steps into the future. The less capable participants used moving averages strategies, whereas the best forecasters matched the real numbers more closely

Forecasting Chaotic Events and the Prediction of a Rare Cognitive Ability

People often live and work in chaotic environments, and thus need to forecast and control what will happen next. The management of chaos is an apparently rare skill, and it would be valuable to identify and develop this skill in the workforce. Untrained undergraduates (N = 147) forecasted number series from four chaotic attractors of varying levels of complexity. They contributed measurements of 16PF personality traits, general intelligence, field independence, and divergent thinking. The results indicated that field independence and personality traits associated with the creative personality profile were the most frequent correlates of performance on forecasting one to four steps into the future. It should be possible to adapt the experimental results to personnel selection and placement decisions that require the search for talent for forecasting

Differential Connexin Function Enhances Self-Renewal in Glioblastoma

The coordination of complex tumor processes requires cells to rapidly modify their phenotype and is achieved by direct cell-cell communication through gap junction channels composed of connexins. Previous reports have suggested that gap junctions are tumor suppressive based on connexin 43 (Cx43), but this does not take into account differences in connexin-mediated ion selectivity and intercellular communication rate that drive gap junction diversity. We find that glioblastoma cancer stem cells (CSCs) possess functional gap junctions that can be targeted using clinically relevant compounds to reduce self-renewal and tumor growth. Our analysis reveals that CSCs express Cx46, while Cx43 is predominantly expressed in non-CSCs. During differentiation, Cx46 is reduced, while Cx43 is increased, and targeting Cx46 compromises CSC maintenance. The difference between Cx46 and Cx43 is reflected in elevated cell-cell communication and reduced resting membrane potential in CSCs. Our data demonstrate a pro-tumorigenic role for gap junctions that is dependent on connexin expression