Coronary Anomalies: Understanding of Normal Coronary Artery Development for Insight in Treatment of Coronary Artery Disease.

Coronary artery anomalies (CAA) are rare congenital abnormalities with incidence of about 1% in the general population.2Unfortunately, despite the low incidence, CAA can cause sudden cardiac death. Identifying the course of the artery is critical for appropriate management. We present a rare case of the left coronary artery arising from the right coronary ostium with special emphasis on normal coronary artery development as possible insight for treatment of diseased heart.

The neural crest and neural crest cells: discovery and significance for theories of embryonic organization.

The neural crest has long fascinated developmental biologists,and,increasingly over the past decades,evolutionary and evolutionary developmental biologists.The neural crest is the name given to the fold of ectoderm at the junction between neural and epidermal ectoderm in neurula-stage vertebrate embryos.In this sense,the neural crest is a morphological term akin to head fold or limb bud.This region of the dorsal neural tube consists of neural crest cells,a special population(s)of cell,that give rise to an astonishing number of cell types and to an equally astonishing number of tissues and organs.Neural crest cell contributions may be direct - providing cells - or indirect - providing a necessary, often inductive, environment in which other cells develop.The enormous range of cell types produced provides an important source of evidence of the neural crest as a germ layer, bringing the number of germ layers to four - ectoderm,endoderm,mesoderm,and neural crest. In this paper I provide a brief overview of the major phases of investigation into the neural crest and the major players involved,discuss how the origin of the neural crest relates to the origin of the nervous system in vertebrate embryos,discuss the impact on the germ-layer theory of the discovery of the neural crest and of secondary neurulation,and present evidence of the neural crest as the fourth germ layer.A companion paper (Hall, Evol. Biol.2008) deals with the evolutionary origins of the neural crest and neural crest cells.

Neurocristopatías pigmentarias névicas / Nevic pigmentary neurocristopathies

Existen tres cuadros con patogenias comunes y manifestaciones clínicas similares: las neurofibromatosis, el síndrome de Albright y el síndrome del nevo pigmentario diseminado. Los tres comparten la presencia en piel de nevos pigmentarios planos, siendo éstos diferentes entre sí desde el punto de vista semiológico, constituyendo un importante signo diagnóstico. Se considera que existe un amplio espectro de enfermedades debidas a alteraciones de la cresta neural y con nevos pigmentarios, para las que se propone la denominación de neurocristopatías pigmentarias névicas