Cholinergic receptor pathways involved in apoptosis, cell proliferation and neuronal differentiation

Acetylcholine (ACh) has been shown to modulate neuronal differentiation during early development. Both muscarinic and nicotinic acetylcholine receptors (AChRs) regulate a wide variety of physiological responses, including apoptosis, cellular proliferation and neuronal differentiation. However, the intracellular mechanisms underlying these effects of AChR signaling are not fully understood. It is known that activation of AChRs increase cellular proliferation and neurogenesis and that regulation of intracellular calcium through AChRs may underlie the many functions of ACh. Intriguingly, activation of diverse signaling molecules such as Ras-mitogen-activated protein kinase, phosphatidylinositol 3-kinase-Akt, protein kinase C and c-Src is modulated by AChRs. Here we discuss the roles of ACh in neuronal differentiation, cell proliferation and apoptosis. We also discuss the pathways involved in these processes, as well as the effects of novel endogenous AChRs agonists and strategies to enhance neuronal-differentiation of stem and neural progenitor cells. Further understanding of the intracellular mechanisms underlying AChR signaling may provide insights for novel therapeutic strategies, as abnormal AChR activity is present in many diseases

Involvement mechanisms for organized crime

This study aims to illuminate the processes that make individuals engage in organized crime activities. Within the diversity of individual involvement processes, several distinctive mechanisms are discussed. Theoretical ideas are illustrated by empirical data on 15 crime groups, including over 300 offenders. The crime groups differ in size, composition, and the nature of criminal activities. Social capital theory is used to understand the dynamical process of becoming involved in organized crime; on the one hand an individual contributes to a crime group, on the other hand the crime group helps an individual reach certain goals. Case studies reveal several resources, such as knowledge, skills, and equipment, that make offenders suit and contribute to a particular organized crime group. Criminal and conventional histories of organized crime offenders turn out to be diverse. Several joint characteristics that opened doors to organized crime opportunities, like running one's own business, are discussed. It is confirmed that involvement through family and long-time friends is common; most criminal groups contain at least one or two relatives. © 2012 Springer Science+Business Media Dordrecht