A barley cysteine-protease inhibitor reduces teh performance of two aphid species in artificial diets and transgenic arabidopsis plants

Cystatins from plants have been implicated in plant defense towards insects, based on their role as inhibitors of heterologous cysteine-proteinases. We have previously characterized thirteen genes encoding cystatins (HvCPI-1 to HvCPI-13) from barley (Hordeum vulgare), but only HvCPI-1 C68 → G, a variant generated by direct-mutagenesis, has been tested against insects. The aim of this study was to analyze the effects of the whole gene family members of barley cystatins against two aphids, Myzus persicae and Acyrthosiphon pisum. All the cystatins, except HvCPI-7, HvCPI-10 and HvCPI-12, inhibited in vitro the activity of cathepsin L- and/or B-like proteinases, with HvCPI-6 being the most effective inhibitor for both aphid species. When administered in artificial diets, HvCPI-6 was toxic to A. pisum nymphs (LC50 = 150 μg/ml), whereas no significant mortality was observed on M. persicae nymphs up to 1000 μg/ml. The effects of HvCPI-6 ingestion on A. pisum were correlated with a decrease of cathepsin B- and L-like proteinase activities. In the case of M. persicae, there was an increase of these proteolytic activities, but also of the aminopeptidase-like activity, suggesting that this species is regulating both target and insensitive enzymes to overcome the effects of the cystatin. To further analyze the potential of barley cystatins as insecticidal proteins against aphids, Arabidopsis plants expressing HvCPI-6 were tested against M. persicae. For A. pisum, which does not feed on Arabidopsis, a combined diet-Vicia faba plant bioassay was performed. A significant delay in the development time to reach the adult stage was observed in both species. The present study demonstrates the potential of barley cystatins to interfere with the performance of two aphid specie

A high implicit affiliation motive does not always make you happy: A corresponding explicit motive and corresponding behavior are further needed

Satisfaction of the implicit affiliation motive is known to be positively related to emotional well-being, whereas the frustration of the implicit affiliation motive leads to impairment of well-being. In the present research we specified two conditions that are responsible for the satisfaction and frustration of the implicit motive. Referring to research on the congruence of implicit and explicit motives, we assumed that a corresponding explicit affiliation motive leads to satisfaction of the implicit motive. Corresponding affiliation behavior constitutes the second condition. Three studies confirmed the hypothesis that both conditions must be fulfilled in order to positively connect the implicit affiliation motive to emotional well-being. Participants with high implicit and explicit affiliation motives and who additionally showed a large amount of affiliation behavior reported the lowest negative affectivity and the highest life satisfaction compared to participants who lacked one of the conditions

Pharmacology of MDMA- and Amphetamine-Like New Psychoactive Substances

New psychoactive substances (NPS) with amphetamine-, aminoindan-, and benzofuran basic chemical structures have recently emerged for recreational drug use. Detailed information about their psychotropic effects and health risks is often limited. At the same time, it emerged that the pharmacological profiles of these NPS resemble those of amphetamine or 3,4-methylenedioxymethamphetamine (MDMA). Amphetamine-like NPS induce psychostimulation and euphoria mediated predominantly by norepinephrine (NE) and dopamine (DA) transporter (NET and DAT) inhibition and transporter-mediated release of NE and DA, thus showing a more catecholamine-selective profile. MDMA-like NPS frequently induce well-being, empathy, and prosocial effects and have only moderate psychostimulant properties. These MDMA-like substances primarily act by inhibiting the serotonin (5-HT) transporter (SERT) and NET, also inducing 5-HT and NE release. Monoamine receptor interactions vary considerably among amphetamine- and MDMA-like NPS. Clinically, amphetamine- and MDMA-like NPS can induce sympathomimetic toxicity. The aim of this chapter is to review the state of knowledge regarding these substances with a focus on the description of the in vitro pharmacology of selected amphetamine- and MDMA-like NPS. In addition, it is aimed to provide links between pharmacological profiles and in vivo effects and toxicity, which leads to the conclusion that abuse liability for amphetamine-like NPS may be higher than for MDMA-like NPS, but that the risk for developing the life-threatening serotonin syndrome may be increased for MDMA-like NPS

Achievement incentives determine the effects of achievement-motive incongruence on flow experience

Previous research has shown that incongruence between implicit and explicit achievement motives impairs flow experience. We examined this relationship in a more differentiated manner by arguing that achievement-motive incongruence only exerts negative effects when individuals act in situations in which achievement incentives are present and arouse conflict between the two motives. In non-achievement situations, no negative effects of achievement-motive incongruence on flow experience are expected. Study 1 and Study 2 showed that participants with incongruent implicit and explicit achievement motives reported less flow in achievement- as compared to non-achievement-oriented sport situations. In Study 3, we experimentally manipulated achievement and non-achievement situations. Again, motive incongruence impaired the experience of flow in achievement but not in non-achievement situations