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Semantic function of the mammalian tail in the design of anal pole of the body
Baxa, Marek ; Komárek, Stanislav (advisor) ; Kleisner, Karel (referee)
The tail in mammals is an important organ, which in contrast to most vertebrae, doesn't add to the motor function of their bodies. The use of the mamals' tail is much more varied and it can fulfill many different functions. This work includes a survey of these functions and analyzes collected data concerning 553 spieces of mammals across all families. The data includes information about the length of tail, the length of body, body mass, living environment and outer signs on the anal pole of these species. The resulting analysis concludes that the tail length is dependent both on the length of the mammal's body and its living environment. Outward signs of the tail depend on its length as well as the length of the body and the living environment. Distinctive tail ending and tail base probably fulfill a communicative function. The tail is more likely to have communication than cryptic significance.
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Study of regenerative potential of Sertoli cell progenitors in Xenopus tropicalis tadpoles after tail amputation.
Wróblová, Aneta ; Krylov, Vladimír (advisor) ; Procházka, Jan (referee)
African clawed frogs (Xenopus) represent an ideal model organism for study of regeneration mechanisms. In frogs, complete regeneration occurs in the tadpole stage. In later stages the regeneration capacity is lost. The Laboratory of Developmental biology was successful in establishment of cell culture called Xenopus tropicalis immature Sertoli cells (XtiSCs) derived from X. tropicalis testes. These cells are common progenitors of Sertoli cells and peritubular myoid cells. XtiSCs show similar characteristics as mesenchymal stem cells. MSCs hold interest of scientists for their immunomodulatory properties and multipotent differential and regeneration potential. In this thesis, we studied regeneration and migration potential of XtiSCs after X. tropicalis tadpole's tail amputation in developmental stage 47 - 50. Transgenic XtiSCs culture expressing RFP was prepared to facilitate transplantation experiments. Transplantation experiments showed preferential migration of XtiSCs into the site of injury. XtiSCs transplantations in X. laevis tadpoles with downregulated NO synthases eNOS and nNOS revealed their migratory dependence on nitric oxide signalization. Imunocytochemical staining of XtiSCs in vitro showed positive iNOS, nNOS and Pax7 expression. Imunohistochemical staining of tadpole's tail vibratome...
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Shared mechanisms of development of vertebrate body appendages
Vintr, Jan ; Soukup, Vladimír (advisor) ; Krylov, Vladimír (referee)
Vertebrate body appendages include a number of structures such as limbs, paired and median fins, the tail bud, the cloacal region, barbels or pharyngeal arch derivatives. Despite differences in form and function, these appendages share a number of developmental genetic mechanisms. Development of these structures is chiefly regulated by Fgf, Shh, Wnt, Tgf-β and retinoic acid signalling pathways, activity of transcription factors such as Hox or Tbx along with cis-regulatory elements controlling the genes in which these factors are encoded. A recurring feature shared by some of the herein discussed anatomical structures is a transient epithelial ridge whose activity influences production and proliferation of the adjacent mesenchyme. Some are also instructed by a signalling centre, which confers asymmetry to the structure. In this text, the various appendages are compared on the basis of their development in relation to tetrapod limbs and theories evaluating the emergence of vertebrate paired appendages. The fin fold theory and archipterygial theory are discussed in the light of recent data provided by evolutionary developmental biology. All together, this thesis evaluates shared and derived characteristics of vertebrate body appendages with the aim to provide a basis for the upcoming work on the role...
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Semantic function of the mammalian tail in the design of anal pole of the body
Baxa, Marek ; Komárek, Stanislav (advisor) ; Kleisner, Karel (referee)
The tail in mammals is an important organ, which in contrast to most vertebrae, doesn't add to the motor function of their bodies. The use of the mamals' tail is much more varied and it can fulfill many different functions. This work includes a survey of these functions and analyzes collected data concerning 553 spieces of mammals across all families. The data includes information about the length of tail, the length of body, body mass, living environment and outer signs on the anal pole of these species. The resulting analysis concludes that the tail length is dependent both on the length of the mammal's body and its living environment. Outward signs of the tail depend on its length as well as the length of the body and the living environment. Distinctive tail ending and tail base probably fulfill a communicative function. The tail is more likely to have communication than cryptic significance.
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