Neurogenic niches in the adult mammalian brain are composed of heterogeneous populations of neural stem cells. In this issue of Neuron, Codega et al. (2014) isolate quiescent neural stem cells from the adult subventricular zone and demonstrate their stem cell characteristics.

Two regions of the chick limb bud--the apical ectodermal ridge and the zone of polarizing activity--have been shown to influence cell division and pattern formation during normal development and following surgical manipulation. In this study, using a simple coculture system, together with autoradiography, we have shown that these morphogenetically active regions of the limb bud can stimulate qu...

Drosophila hematopoiesis occurs in a specialized organ called the lymph gland. In this systematic analysis of lymph gland structure and gene expression, we define the developmental steps in the maturation of blood cells (hemocytes) from their precursors. In particular, distinct zones of hemocyte maturation, signaling and proliferation in the lymph gland during hematopoietic progression are desc...

Endothelial cells (EC) both inhibit and promote platelet function depending on their activation state. Quiescent EC inhibit platelet activation by constitutive secretion of platelet inhibitors. Activated EC promote platelet adhesion by secretion of von Willebrand factor (vWF). EC also secrete an extracellular matrix that support platelet adhesion when exposed following vascular injury. Previous...

We report the redox status (profiles) for specific populations of cells that comprise the Arabidopsis root tip. For recently germinated, 3-5-day-old seedlings we show that the region of the root tip with the most reduced redox status includes the root cap initials, the quiescent center and the most distal portion of the proximal meristem, and coincides with (overlays) the region of the auxin ma...

Activity based sampling (ABS) is typically performed to assess inhalation exposure to particulate contaminants known to have low, heterogeneous concentrations on a surface. Activity based sampling determines the contaminant concentration in a person's breathing zone as they perform a scripted activity, such as raking a specified area of soil, while wearing appropriate sample collection instrume...

BACKGROUND Characterization of the niches for stem-like tumor cells is important to understand and control the behavior of glioblastomas. Cell-cycle quiescence might be a common mechanism underlying the long-term maintenance of stem-cell function in normal and neoplastic stem cells, and our previous study demonstrated that quiescence induced by hypoxia-inducible factor (HIF)-1α is associated wi...

Neural stem cells (NSCs) generate new neurons in vivo and in vitro throughout adulthood and therefore are physiologically and clinically relevant. Unveiling the mechanisms regulating the lineage progression from NSCs to newborn neurons is critical for the transition from basic research to clinical application. However, the direct analysis of NSCs and their progeny is still elusive due to the pr...

A major outstanding problem in solar physics is the confinement of tachocline, thin shear layer that separates nearly solid-body rotation radiative interior from strong differential convection zone. Here, we present first 3-D, global simulation which a tachocline confined by self-excited dynamo. The non-axisymmetric magnetism initially built zone and then diffusively imprints downward. Addition...

purpose: to evaluate the role of active uveitis on refractive errors changes. methods: a cohort single group study was conducted on patients with acute or recurrent uveitis. cyclorefraction was performed in both phases of active and quiescent. sphere, cylinder and sphere equivalent power were compared in active and quiescent phases and analyzed statistically. results: sixty-six patients (eighty...