Recent advances have given us new insights into the molecular basis of organ position. A gene cascade that determines left-right positioning of organ primordia has emerged. In here we present the current knowledge of the molecular determinants of organ positioning during vertebrate embryogenesis.

Vertebrates display left-right (L-R) asymmetric organ positioning and morphologies, which are established during embryonic development. These asymmetries are conserved among individuals and species. How, when and where do embryos first break the symmetry? Why is it broken in a consistent direction? How is the asymmetry transmitted to and coordinated within the whole embryo? Which of these eleme...

background: heart disease is the main cause of mortality and morbidity in patients with beta thalassemia, rendering its early diagnosis vital. we studied and compared echocardiographic findings in patients with beta thalassemia major, patients with beta thalassemia intermedia, and a control group. methods: eighty asymptomatic patients with thalassemia major and 22 asymptomatic cases with thalas...

n this issue of JAAA, Tori Gustafson and Teri Hamill add another set of data to a growing array of evidence suggesting subtle asymmetries in the binaural auditory system . Subjects with simulated unilateral conductive hearing loss, created by insertion of an earplug, were seated in a sound-treated chamber before a semicircular array of 13 loudspeakers . Then, 3000-Hz warble tones of 1-second du...

‎we present a characterization of arens regular semigroup algebras‎ ‎$ell^1(s)$‎, ‎for a large class of semigroups‎. ‎mainly‎, ‎we show that‎ ‎if the set of idempotents of an inverse semigroup $s$ is finite‎, ‎then $ell^1(s)$ is arens regular if and only if $s$ is finite‎.

Contrary to the opinion of French pediatrician HenriLouis that isolated ventricular septal defects (VSDs) are universally well tolerated, the subsequent discoveries of Eisenmenger, Abbott, Wood, and others have taught us that the prognosis of left-to-right shunt lesions is not always benign. After more than a century of research, as pediatric cardiologists and congenital heart surgeons, we clai...