No abstract

In colonies of Cataglyphis cursor ants, a single queen mates with multiple males, creating the foundation for heritable behavioral specializations. A novel and unique candidate for such specializations is rescue behavior, a precisely delivered form of altruism in which workers attempt to release trapped nestmates and which relies on short-term memory of previous actions to increase its efficiency. Consistent with task specialization, not all individuals participate; instead, some individuals move away from the victim, which gives rescuers unrestricted access. Using a bioassay to identify rescuers and non-rescuers, coupled with paternity assignment via polymorphic microsatellite markers, we not only show that rescue behavior is heritable, with 34% of the variation explained by paternity, but also establish that rescue, heretofore overlooked in analyses of division of labor, is a true specialization, an ant version of first responders. Moreover, this specialization emerges as early as 5 days of age, and the frequency of rescuers remains constant across ants’ age ranges. The extremely broad range of these ants’ heritable polyethism provides further support for the critical role of polyandry in increasing the efficiency of colony structure and, in turn, reproductive success.

T reaTmenT management strategies for pituitary macroadenomas depend on numerous factors that guide the determination of medical management, surgical approach, and/or adjuvant therapeutic options. Maximal resection and adequate decompression of the neurological structures is the paradigm of care for symptomatic pituitary macroadenomas, with the exception of medically responsive prolactinomas.Since its inception by Schloffer in 1907 and then refinement and popularization by Hirsch, Guiot, and Hardy, the transsphenoidal approach has become the preferred route to the sella because of its relative safety profile. 9,14,16,17 The transcranial route still plays an important role in providing access to the sella in 1% to 4% of pituitary macroadenomas where direct visualization and accessibility via the transsphenoidal approach are limited. 38A transcranial approach should be considered in the surgical management of pituitary adenomas that display constriction at the diaphragma sellae, parasellar extension or inaccessible suprasellar extension off the midline, tumors of fibrous consistency with large suprasellar extension, and in patients with an active sinus infection or a coexisting adjacent aneurysm. Other cases that should be approached transcranially include those patients with ectatic intrasellar carotid arteries, 40 retrosellar extension, brain invasion with edema, involvement or vasospasm of the arteries of the circle of Willis, or encasement of the optic apparatus or invasion of the optic foramina. obJective Oculomotor cistern extension of pituitary adenomas is an overlooked feature within the literature. In this study, 7 cases of pituitary macroadenoma with oculomotor cistern extension and tracking are highlighted, and the implications of surgical and medical management are discussed. methods The records of patients diagnosed with pituitary macroadenomas who underwent resection and in whom preoperative pituitary protocol MRI scans were available for review were retrospectively reviewed. The patient and tumor characteristics were reviewed along with the operative outcomes and complications. results Seven patients (4.1%) with oculomotor cistern extension and tracking were identified in a cohort of 170 patients with pituitary macroadenoma. The most common presenting symptoms were visual deficit (6 patients; 86%), apoplexy (3 patients; 43%), and oculomotor nerve palsy (3 patients; 43%). Lone oculomotor nerve palsy was seen in 2 patients without apoplexy and 1 patient with an apoplectic event. Gross-total resection was achieved via a microscopic endonasal transsphenoidal approach with or without endoscopic aid to the sella in 14%, near-total resection in 29%, and subtotal resection in 57% of patients in the data set. coNclusioNs Pituitary adenoma extension along the oculomotor cistern is uncommon; however, preoperatively recognizing such extension should play an important role in the surgeon's operative considerations and postoperative clinical management because this extension can limit gross-total resection using t...

The abscission checkpoint regulates the ESCRT membrane fission machinery and thereby delays cytokinetic abscission to protect genomic integrity in response to residual mitotic errors. The checkpoint is maintained by Aurora B kinase, which phosphorylates multiple targets, including CHMP4C, a regulatory ESCRT-III subunit necessary for this checkpoint. We now report the discovery that cytoplasmic abscission checkpoint bodies (ACBs) containing phospho-Aurora B and tri-phospho-CHMP4C develop during an active checkpoint. ACBs are derived from Mitotic Interchromatin Granules (MIGs), transient mitotic structures whose components are housed in splicing-related nuclear speckles during interphase. ACB formation requires CHMP4C, and the ESCRT factor ALIX also contributes. ACB formation is conserved across cell types and under multiple circumstances that activate the checkpoint. Finally, ACBs retain a population of ALIX, and their presence correlates with delayed abscission and delayed recruitment of ALIX to the midbody where it would normally promote abscission. Thus, a cytoplasmic mechanism helps regulate midbody machinery to delay abscission.