Cast: a novel protein of the cytomatrix at the active zone of synapses that forms a ternary complex with RIM1 and munc13-1

The cytomatrix at the active zone (CAZ) has been implicated in defining the site of Ca2+-dependent exocytosis of neurotransmitter. We have identified here a novel CAZ protein of ∼120 kD from rat brain and named it CAST (CAZ-associated structural protein). CAST had no transmembrane segment, but had four coiled-coil domains and a putative COOH-terminal consensus motif for binding to PDZ domains. CAST was localized at the CAZ of conventional synapses of mouse brain. CAST bound directly RIM1 and indirectly Munc13-1, presumably through RIM1, forming a ternary complex. RIM1 and Munc13-1 are CAZ proteins implicated in Ca2+-dependent exocytosis of neurotansmitters. Bassoon, another CAZ protein, was also associated with this ternary complex. These results suggest that a network of protein–protein interactions among the CAZ proteins exists at the CAZ. At the early stages of synapse formation, CAST was expressed and partly colocalized with bassoon in the axon shaft and the growth cone. The vesicles immunoisolated by antibassoon antibody–coupled beads contained not only bassoon but also CAST and RIM1. These results suggest that these CAZ proteins are at least partly transported on the same vesicles during synapse formation

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ABSTRACT Context Intraductal papillary mucinous neoplasms (IPMNs) of the pancreas have been detected with increasing frequency as a result of the progression of diagnostic modalities. Recently, invasive ductal carcinoma of the pancreas concomitant with IPMNs has been the focus of attention. Case report We report the case of a 57-year-old man with multifocal ductal carcinomas of the pancreas concomitant with IPMNs detected by intraoperative cytology. During a follow-up for branch duct IPMNs, a stenotic lesion of the main duct in the pancreatic body was found by ERCP, and brush cytology of the stenosis revealed an adenocarcinoma. A distal pancreatectomy was proposed; however, intraoperative pancreatic juice cytology from the pancreatic head also revealed adenocarcinoma, and a total pancreatectomy was finally carried out. Pathological examination of the resected specimen showed multifocal ductal carcinomas and IPMNs in the distal pancreas, and invasive ductal carcinoma in the pancreatic head which had not been detected by preoperative imaging studies. Conclusions Surgeons should be aware of the possibility of multifocal carcinomas in patients with concomitant IPMNs. Intraoperative pancreatic juice cytology should always be performed in order to confirm the absence of carcinoma in the pancreas to be left in place after planned resection

Social entrepreneurship: problems and ways of their solution

For modern constantly developing societies, it is normal to create categories in the process of the activity of the participants of socio-economic processes themselves. Practice is theoretical, and theory is pragmatic, because it creates those concepts in which «practice» exists and develops. Such a category is "social entrepreneurship", which is "umbrella" for a number of socio-economic phenomena. The general term for social entrepreneurship includes those types of entrepreneurial activity that contradict the traditional notion of entrepreneurship as an activity of independent economic entities aimed at maximizing their profits. The development of social entrepreneurship is an indicator of the quality of the business climate in the region and requires a set of measures to ensure the mechanism and access of non-governmental organizations to the provision of services in the social sphere, the provision of state support to socially-oriented non-profit organizations, and the promotion of the development of PPP practices in the social sphere