Adverse events in spine surgery: a prospective analysis at a large tertiary center in Germany.

Study Design: Prospective study OBJECTIVES: The occurrence of adverse events (AEs) during surgery is a major cause of increased economic costs, disability, or even death. This study aimed to prospectively identify and quantify AEs in patients undergoing spinal surgery at a neurosurgical tertiary care hospital.

Methods: Patients who underwent spinal surgery and were discharged between January 2019 and December 2022 were enrolled prospectively.

The use of quantitative pupillometry in patients with pituitary tumors: a technical note.

Background: Pituitary tumors may cause compression of the optic chiasm, resulting in decreased visual acuity. Therefore, decompression of the optic chiasm is a major goal of surgical treatment in such patients. Quantitative pupillometry has been used in various clinical settings for assessing the optic system but has not been applied in patients with pituitary tumors.

Dynamics of a Volvox embryo turning itself inside out.

Deformations of cell sheets are ubiquitous in early animal development, often arising from a complex and poorly understood interplay of cell shape changes, division, and migration. Here, we explore perhaps the simplest example of cell sheet folding: the "inversion" process of the algal genus Volvox, during which spherical embryos turn themselves inside out through a process hypothesized to arise from cell shape changes alone. We use light sheet microscopy to obtain the first three-dimensional visualizations of inversion in vivo, and develop the first theory of this process, in which cell shape changes appear as local variations of intrinsic curvature, contraction and stretching of an elastic shell.

Polarization of PAR proteins by advective triggering of a pattern-forming system.

In the Caenorhabditis elegans zygote, a conserved network of partitioning-defective (PAR) polarity proteins segregates into an anterior and a posterior domain, facilitated by flows of the cortical actomyosin meshwork. The physical mechanisms by which stable asymmetric PAR distributions arise from transient cortical flows remain unclear. We present evidence that PAR polarity arises from coupling of advective transport by the flowing cell cortex to a multistable PAR reaction-diffusion system.

Origin of correlated activity between parasol retinal ganglion cells.

Cells throughout the CNS have synchronous activity patterns; that is, a cell's probability of generating an action potential depends both on its firing rate and on the occurrence of action potentials in surrounding cells. The mechanisms producing synchronous or correlated activity are poorly understood despite its prevalence and potential effect on neural coding. We found that neighboring parasol ganglion cells in primate retina received strongly correlated synaptic input in the absence of modulated light stimuli.