Acute Finger Ischemia in an Elderly Male without Risk Factors for Hypercoagulability.

Literature on ulnar artery thrombosis and acute finger ischemia is scant and usually related to underlying hypercoagulable or occlusive states, such as atrial fibrillation, thrombangiitis obliterans, vasospasm, trauma, and neurovascular compression at the root of the upper limb. An elderly hypertensive male without an underlying hypercoagulable state, and in otherwise good health, presented to our emergency department with acute multi-finger ischemia, and ulnar artery and palmar arch thromboses. Given his innocuous history, this case demonstrates the importance of maintaining acute arterial thrombosis on the differential for hand pain despite the obvious propensity toward mechanical injuries in the extremities.

The age of enlightenment: evolving opportunities in brain research through optical manipulation of neuronal activity.

Optical manipulation of neuronal activity has rapidly developed into the most powerful and widely used approach to study mechanisms related to neuronal connectivity over a range of scales. Since the early use of single site uncaging to map network connectivity, rapid technological development of light modulation techniques has added important new options, such as fast scanning photostimulation, massively parallel control of light stimuli, holographic uncaging, and two-photon stimulation techniques. Exciting new developments in optogenetics complement neurotransmitter uncaging techniques by providing cell-type specificity and in vivo usability, providing optical access to the neural substrates of behavior.

Parallel optical control of spatiotemporal neuronal spike activity using high-speed digital light processing.

Neurons in the mammalian neocortex receive inputs from and communicate back to thousands of other neurons, creating complex spatiotemporal activity patterns. The experimental investigation of these parallel dynamic interactions has been limited due to the technical challenges of monitoring or manipulating neuronal activity at that level of complexity. Here we describe a new massively parallel photostimulation system that can be used to control action potential firing in in vitro brain slices with high spatial and temporal resolution while performing extracellular or intracellular electrophysiological measurements.