Human iPSC-Derived Neurons with Reliable Synapses and Large Presynaptic Action Potentials.

Understanding the function of the human brain requires determining basic properties of synaptic transmission in human neurons. One of the most fundamental parameters controlling neurotransmitter release is the presynaptic action potential, but its amplitude and duration remain controversial. Presynaptic action potentials have so far been measured with high temporal resolution only in a limited number of vertebrate but not in human neurons.

Computed tomographic laryngotracheal dimensions in adult domestic rabbits (Oryctolagus cuniculus) are positively associated with body weight and the laryngotracheal lumen is narrowest at the level of the thyroid cartilage.

Objective: This retrospective study aimed to measure rabbit laryngotracheal dimensions at different locations on computed tomography (CT), assess the relationship of these measurements with rabbit body weight, determine the most common narrowest measurement and assess its relationship with endotracheal tube (ETT) size and body weight.

Animals: 66 adult domestic rabbits (Oryctolagus cuniculus) of different breeds and body weights.

Procedures: CT laryngotracheal luminal height, width, and cross-sectional area measurements were made at the rostral thyroid cartilage at the level of the arytenoids, caudal thyroid cartilage/rostral cricoid cartilage, caudal cricoid cartilage/cranial trachea, and trachea at the level of the fifth cervical vertebra.

Tau Protein Modulates Perineuronal Extracellular Matrix Expression in the TauP301L- Mouse Model.

Tau mutations promote the formation of tau oligomers and filaments, which are neuropathological signs of several tau-associated dementias. Types of neurons in the CNS are spared of tau pathology and are surrounded by a specialized form of extracellular matrix; called perineuronal nets (PNs). Aggrecan, the major PN proteoglycans, is suggested to mediate PNs neuroprotective function by forming an external shield preventing the internalization of misfolded tau.

Caspase-cleaved tau is senescence-associated and induces a toxic gain of function by putting a brake on axonal transport.

The microtubule-associated protein tau plays a central role in tauopathies such as Alzheimer's disease (AD). The exact molecular mechanisms underlying tau toxicity are unclear, but aging is irrefutably the biggest risk factor. This raises the question of how cellular senescence affects the function of tau as a microtubule regulator.