Search results for "Chimaera"
showing 3 items of 3 documents
Holocephalan (Chondrichthyes) dental plates with hypermineralized dentine as a substitute for missing teeth through developmental plasticity.
2020
All extant holocephalans (Chimaeroidei) have lost the ability to make individual teeth, as tooth germs are neither part of the embryonic development of the dental plates, nor of their continuous growth. Instead, a hypermineralized dentine with a unique mineral, whitlockin, is specifically distributed within a dentine framework into structures that give the dental plates their distinctive, species-specific morphology. Control of the regulation of this distribution must be cellular, with a dental epithelium initiating the first outer dentine, and via contact with ectomesenchymal tissue as the only embryonic cell type that can make dentine.\ud Chimaeroids have three pairs of dental plates with…
Su due sculture minori di Alessandria e Leptis Magna
2018
This paper focuses on two marble sculptures representing Bellerophon with the Chimaera, now in the Alexandria and Lepcis Magna Museums, which received the attention of the late Professor Nicola Bonacasa several decades ago. Carved in Proconnesian marble and rendered with a very close iconography, they are part of a larger group of about ten trapezophora with the same subject. Pointing out more on differences among these exemplares than on their analogies, after some considerations on the long debate about the function and the meaning of these sculptures as well as on the geography of the myth of the Chimaera, a new interpretation of the myth is proposed, not as unique but co-existing with t…
Evaluación de las células de la blastema de aleta caudal como donantes en quimeras intraespecíficas de pez cebra
2008
The blastema is a regenerative tissue with remarkable pluripotency. The aim of this work done on zebrafish (Danio rerio) was to define technical procedures required for obtaining and integrating blastema cells into embryos at the mid blastula transition stage (MBT) and the effect on survival, as well as the capacity to produce pigmented chimaeras. Wild type blastema cells were injected into gold type MBT embryos (E). Wild MBT blastomere cells were also injected into gold type MBT embryos as a control (C1). A second control group, C2, was not subjected to any manipulation. Survival was evaluated at 24, 48 and 72 h after performing the chimaerism, and the rate of adult chimaeras evaluated. Th…