Expression of arthropod distal limb-patterning genes in the onychophoran Euperipatoides kanangrensis.

A current hypothesis states that the ancestral limb of arthropods is composed of only two segments. The proximal segment represents the main part of the modern leg, and the distal segment represents the tarsus and claw of the modern leg. If the distal part of the limb is an ancestral feature, one would expect conserved regulatory gene networks acting in distal limb development in all arthropods and possibly even their sister group, the onychophorans.

Chromic acid poisoning treated with acute hemodialysis.

Poisoning with chromium compounds is rare, but often serious. The symptoms are quite characteristic, the most dramatic of these being circulatory collapse, hepatic and renal failure. A case is reported where an 18-year-old woman ingested 5 g of chromic acid.