Memorial University of Newfoundland

About: Memorial University of Newfoundland is a education organization based out in St. John's, Newfoundland and Labrador, Canada. It is known for research contribution in the topics: Population & Gadus. The organization has 13818 authors who have published 27785 publications receiving 743594 citations. The organization is also known as: Memorial University & Memorial University of Newfoundland and Labrador.

Preventing Nephropathy Induced by Contrast Medium

Abstract: A 71-year-old man with type 2 diabetes and hypertension is referred for coronary angiography. His medications include metformin and a thiazide. Before the angiogram, his serum creatinine level is 1.8 mg per deciliter (160 μmol per liter), yielding an estimated glomerular filtration rate of 40 ml per minute per 1.73 m 2 of body-surface area. What can be done to reduce the risk that an angiographic contrast medium will worsen his kidney function?

Viscerotopic representation of the upper alimentary tract in the medulla oblongata in the rat: the nucleus ambiguus.

Abstract: The nucleus ambiguus has been reported to innervate various thoracic and abdominal viscera in addition to the musculature of the upper alimentary tract. However, the literature is contradictory as to how different regions of the nucleus ambiguus innervate specific organs. Therefore, a systematic investigation of the viscerotopic organization of the nucleus ambiguus was undertaken. In 102 rats, 0.5–10.0 μl of HRP, WGA-HRP, cholera toxin-HRP or fluorescent tracers were injected into the IXth, Xth, and XIth cranial nerves and the major branches of the Xth as well as organs supplied by them. The results demonstrate that the nucleus ambiguus in the rat is made up of two major longitudinal divisions: a dorsal division comprised of three rostrocaudally aligned subdivisions representing the special visceral efferent component, and a ventral division comprised of at least two subdivisions representing the general visceral efferent component. The dorsal division corresponds to the nucleus ambiguus in the narrow sense and comprises a rostral esophagomotor compact formation, an intermediate pharyngolaryngomotor semicompact formation, and a caudal laryngomotor loose formation. Each of these formations displays a characteristic dendroarchitecture. The stylopharyngeal and cricothyroid motoneurons are displaced rostrad from the main pharyngeal and laryngeal motoneuronal pools. Thyropharyngeal (lower constrictor) motoneurons occupy the rostral half of the semi-compact formation and hyopharyngeal (middle constrictor) motoneurons its entire length. The ventral division of the nucleus ambiguus corresponds to the external formation, extends along the entire length of the medulla oblongata, and contains preganglionic neurons innervating the heart and supradiaphragmatic structures innervated by the glossopharyngeal and the superior laryngeal nerves.