Charge Density Influences C1 Domain Ligand Affinity and Membrane Interactions

The C1 domain, which represents the recognition motif on protein kinase C for the lipophilic second messenger diacylglycerol and its ultrapotent analogues, the phorbol esters, has emerged as a promising therapeutic target for cancer and other indications. Potential target selectivity is markedly enhanced both because binding reflects ternary complex formation between the ligand, C1 domain, and phospholipid, and because binding drives membrane insertion of the C1 domain, permitting aspects of the C1 domain surface outside the binding site, per se, to influence binding energetics. Here, focusing on charged residues identified in atypical C1 domains which contribute to their loss of ligand binding activity, we showed that increasing charge along the rim of the binding cleft of the protein kinase C δ C1 b domain raises the requirement for anionic phospholipids. Correspondingly, it shifts the selectivity of C1 domain translocation to the plasma membrane, which is more negatively charged than internal membranes. This change in localization is most pronounced in the case of more hydrophilic ligands, which provide weaker membrane stabilization than do the more hydrophobic ligands and thus contributes an element to the structure–activity relations for C1 domain ligands. Coexpressing pairs of C1‐containing constructs with differing charges each expressing a distinct fluorescent tag provided a powerful tool to demonstrate the effect of increasing charge in the C1 domain.     

Using geographic information systems to assess conflicts between agriculture and development

The conflict between agriculture and urban development is intense in urbanizing areas of the United States and is a problem best resolved at the local level. To effectively develop and apply techniques for preserving farmland, areas of conflict must be identified. This article describes the application of a geographic information system (GIS) for determining the location and level of conflict between agriculture and other forms of human intervention. The procedures used for assessing conflicts are described through a case study in the city of Westfield, Massachusetts and the findings show that GIS can be an effective tool for local decision makers, allowing alternative strategies to be developed and evaluated for agricultural protection.     

GC–MS metabolomics revealed protocatechuic acid as a cytotoxic and apoptosis-inducing compound from black rice brans

Food Science and Biotechnology - GC–MS metabolomics was used to discriminate the phytochemicals profile of Indonesian white, red, and black rice brans, and Japanese white rice brans. This...     

Electrical and Mechanical Behavior of Aerosol Jet–Printed Gold on Alumina Substrate for High-Temperature Applications

There is a growing interest in the development of microelectronics that can perform reliably and robustly at temperatures above 300 °C. Such devices require stable thermal properties, low thermal drift, and thermal cycling resistance. Conventional hybrid circuit technology demonstrates high-temperature packages, but the high costs and lead time are significant drawbacks. In contrast, additive manufacturing processes, including aerosol jet printing (AJP), offer cost and time benefits, as well as 3D structures and embedded features. However, the properties and reliability of additive packaging materials at extreme temperatures are not well known. Herein, the reliability at temperatures up to 750 °C in terms of electrical performance and mechanical strength of aerosol jet printed gold thick films onto ceramic substrates are assessed. Thermal coefficient of resistance of printed gold films is measured. The electrical resistance stability and leakage current of printed gold structures are also characterized during over 100 h of aging at temperatures up to 750 °C. Finally, the mechanical adhesion strength of the printed gold films is evaluated after aging for 100 h at temperatures up to 750 °C. The adhesion of the printed gold to the ceramic substrates remains high after aging, very stable resistances and minimal leakage currents have been observed.     

Young children's self-regulated learning and contexts that support it.

Writing and portfolio activities provided a context for examining relations between classroom contexts and young children's self-regulated learning (SRL). Data collection spanned 6 months and included weekly visits to Grade 2 and 3 classrooms during regularly scheduled writing and portfolio activities. Data included teacher questionnaires and observations and student questionnaires, observations, and interviews. Young children deliberated about how to regulate writing and demonstrated either mastery or performance orientations as a function of classroom-specific tasks, authority structures, and evaluation practices. Findings support sociocognitive models of learning regarding how classroom contexts affect students' beliefs, values, expectations, and actions. Also they challenge assumptions that young children lack the cognitive sophistication required for SRL and do not adopt motivational orientations that undermine it. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The social consequences of expressive suppression.

At times, people keep their emotions from showing during social interactions. The authors' analysis suggests that such expressive suppression should disrupt communication and increase stress levels. To test this hypothesis, the authors conducted 2 studies in which unacquainted pairs of women discussed an upsetting topic. In Study 1, one member of each pair was randomly assigned to (a) suppress her emotional behavior, (b) respond naturally, or (c) cognitively reappraise in a way that reduced emotional responding. Suppression alone disrupted communication and magnified blood pressure responses in the suppressors' partners. In Study 2, suppression had a negative impact on the regulators' emotional experience and increased blood pressure in both regulators and their partners. Suppression also reduced rapport and inhibited relationship formation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Specificity of meta-emotion effects on moral decision-making.

A recently proposed dual process theory of moral decision-making posits that utilitarian reasoning (approving of harmful actions that maximize good consequences) is the result of cognitive control of emotion. This suggests that deficits in emotional awareness will contribute to increased utilitarianism. The present study explored the relative contributions of the different facets of alexithymia and the closely related constructs of emotional intelligence and mood awareness to utilitarian decision making. Participants (N = 86) completed the Toronto Alexithymia Scale, Trait Meta Mood Scale, the Mood Awareness Scale, and a series of high-conflict, personal moral dilemmas validated by Greene et al. (2008). A brief neuropsychological battery was also administered to assess the possible confounds of verbal reasoning and abstract thinking ability. Principal components analysis revealed two latent factors—clarity of emotion and attention to emotion—which cut across all three meta-emotion instruments. Of these, low clarity of emotion—reflecting difficulty in reasoning thoughtfully about one's emotions—predicted utilitarian outcomes and provided unique variance beyond that of verbal and abstract reasoning abilities. Results are discussed in the context of individual differences in emotion regulation. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Cardiovascular effects of platelet-activating factor

Sudden release of platelet-activating factor (PAF) into the circulation can cause hypotension, tachycardia, and circulatory collapse. To further examine this response, we performed detailed studies of cardiovascular function after PAF administration to young domestic pigs and newborn piglets. Our results indicate that circulatory dysfunction after PAF reflects severe constriction of pulmonary resistance vessels and consequent acute right ventricular failure. Although PAF-induced coronary artery constriction and contractile depression may be complicating problems, left ventricular underperfusion and dysfunction after PAF are mainly the result of systemic arterial hypotension and diminished left ventricular filling. The adverse hemodynamic effects of PAF are accompanied by substantial release of thromboxane A₂ (TxA₂). These effects are mimicked by the TxA₂ agonist U-46619 and partially blocked by specific and nonspecific inhibitors of TxA₂ synthesis (OKY-046 and indomethacin). Even more potent blockade of PAF action is exerted by the TxA₂ receptor blocker, SQ 29,548. Taken together, these findings indicate that severe pulmonary vascular constriction and hemodynamic collapse soon after intravenous PAF are at least partially mediated by PAF-induced TxA₂ release. Tachyphylaxis to PAF influence has been observed in studies of leukocyte and platelet function. We hypothesized that tachyphylaxis to PAF might also occur in our studies of constrictor responses in pulmonary vessels. Recently, we have examined the capacity of PAF to produce sustained pulmonary vasoconstriction in openchested, anesthetized newborn piglets. Infusions sufficient to produce 100% increase in mean pulmonary artery pressure after 3 min showed no loss of efficacy when sustained for 30 min. The same was true for infusions of U-46619. Thus, the pulmonary vasoconstrictor influence of PAF or U-46619 is not readily diminished by tachyphylaxis. These findings favor the viewpoint that PAF or TxA₂ release during inflammatory processes could have prolonged adverse actions on pulmonary and systemic circulations. Based on a paper presented at the Third International Conference on Platelet-Activating Factor and Structurally Related Alkyl Ether Lipids, Tokyo, Japan, May 1989. The opinions or assertions contained here are those of the authors. They do not reflect the views of the Department of Defense or the Uniformed Services University of the Health Sciences. The experiments reported here were conducted according to the principles set forth in the “Guide for the Care and Use of Laboratory Animals,” Institute of Laboratory Animal Resources, U.S. Department of Health and Human Services (NIH Publ. 85-23, 1985).