RESUMO
Finding traumatic lesions on ancient skeletal remains offers a unique opportunity to investigate the circumstances surrounding the time of death. Here we present the unique find of a late 17th, early 18th century young male from Southern Italy with eight traumatic skull lesions. A detailed anthropological examination using X-ray and 3D CT scanning techniques was conducted in order to evaluate traumatic extent, direction and degree of severity of each skull injury. The nature, number and timing of repair of the traumata suggest that they were intentional blows inflicted in battle. Gross and radiographic evidence shows that the individual survived long after one of these traumata, most likely suffered in a previous battle. Shape, size and location, as well as different orientation and implied trajectory of the multiple wounds, suggest that they were produced by a heavy, sharp cutting weapon. The perimortem aspect of most of the traumata revealed them to be contemporary injuries, suffered in a final assault by a heavy sword during a face-to-face combat. The largest and deepest fracture penetrating the skull cavity possibly resulting in traumatic brain injury was here suggested as the fatal one, even if the victim may have survived for several days prior to death.
Assuntos
Traumatismo Múltiplo/diagnóstico por imagem , Crânio , Armas , Adulto , História do Século XVII , História do Século XVIII , Humanos , Imageamento Tridimensional , Masculino , Paleopatologia , Crânio/diagnóstico por imagem , Crânio/lesões , Tomografia Computadorizada por Raios X , Violência/históriaRESUMO
Gene duplication is considered an important evolutionary mechanism leading to new gene functions. According to the classical model, one gene copy arising from gene duplication retains the ancestral function, whilst the other becomes subject to directional selection for some novel functions. Hence, according to this model, long-term persistence of two paralogous genes is possible only with the acquisition of functional innovation. In the absence of neofunctionalization, one of the duplicate genes may be lost following accumulation of deleterious mutations, ultimately leading to the loss of function. Recently, new mechanisms have been proposed according to which both paralogs are maintained without apparent neofunctionalization. In this paper we describe the molecular evolution of the aspartic proteinase gene family, with particular regard for the nothepsin gene, a sex- and tissue-specific form of aspartic proteinase active in fish. The finding of nothepsin in a reptile is indicative of the presence of this gene in organisms other than fish. However, the failure to find any nothepsin-like gene in avian, murine and human genome suggests that the gene has been lost in certain lineages during evolution. At variance with piscine nothepsin expressed exclusively in female liver under the estrogens action, the reptilian counterpart lacks both tissue and sex specificity, as it is constitutively expressed in different tissues of male and female specimens. The expression of the nothepsin gene in fish and lizard is accompanied by the expression of a paralogous gene encoding for cathepsin D. Functional divergence analysis indicates that cathepsin D accumulated amino acid substitutions, whereas nothepsin retained most of the ancestral functions. Phylogenetic analysis shows a preponderance of replacement substitutions compared to silent substitutions in the branch leading to the cathepsin D clade, whilst nothepsin evolves under negative selection. To explain the loss of the nothepsin gene in certain lineages, we propose a model that takes into account the complementary degenerative mutations occurring in regulatory elements of the promoter regions of the two genes. According to this model, gene loss occurs whenever the two genes acquire the same expression pattern. The coexistence of cathepsin D and nothepsin is explained in terms of metabolic cooperation of the two enzymes.
Assuntos
Ácido Aspártico Endopeptidases/genética , Catepsina D/genética , Evolução Molecular , Peixes/genética , Duplicação Gênica , Lagartos/genética , Sequência de Aminoácidos , Substituição de Aminoácidos , Animais , Sequência de Bases , Dados de Sequência Molecular , FilogeniaRESUMO
In mammals, gonadal functions are regulated by two pituitary gonadotropins, follicle-stimulating hormone (FSH) and luteinizing hormone (LH), that interact with gonadal membrane receptors to activate adenylate cyclase. In comparison to mammalian systems, in squamate reptiles a reduced amount of information exists on gonadotropins and their related receptors. This study is aimed at clarifying if, in the lizard Podarcis sicula, the ovarian sensitivity to FSH is correlated to the reproductive cycle and to the expression of membrane receptors involved in the hormone recognition. The results demonstrate that the ovarian adenylate cyclase responsiveness to FSH parallels ovarian functions, being maximal during the ovulatory period. The ovarian sensitivity to FSH is also related to oocyte growth and vitellogenesis. Northern blot analyses reveal that the FSH receptor mRNA is maximally expressed in vitellogenic oocytes during the reproductive period. These results suggest that, in lizard ovary, hormone activation of adenylate cyclase is mediated by de novo synthesis of receptors specifically involved in FSH recognition. In lizards treated in vivo with FSH during the pre-ovulatory period, adenylate cyclase becomes refractory to further FSH stimulation 2 hr after treatment, but sensitivity to the hormone is restored after 2 weeks. Nevertheless, while the restored level of activity never exceeds that observed during the nonreproductive period, the expression level of FSH receptor mRNAs is significantly enhanced in these animals. These results suggest that in lizard the processes that regulate ovarian growth, vitellogenesis, and ovulation are controlled by a complex network of signals including gonadotropin, FSH receptor expression, and adenylate cyclase.