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991.
The Ceprano calvarium represents one of the most important sources of information about both the dynamics of the earliest hominid dispersal toward Europe and the evolution of the genus Homo in the early-to-middle Pleistocene. In this paper, the midsagittal vault profile and the 3D frontal bone morphology of Ceprano are investigated comparatively, using landmark coordinates and Procrustes superimposition. In fact, despite the fact that the skull appears partially distorted by diagenetic pressures (thus precluding a comprehensive landmark-based analysis), some aspects of the overall morphology are suitable for consideration in terms of geometric morphometrics. The midsagittal profile shows an archaic shape, comparable with the H. ergaster/erectus range of variation because of the fronto-parietal flattening, the development of the supraorbital and nuchal structures, and the occurrence of a slightly larger occipital bone. By contrast, the frontal bone displays a derived 3D shape that, mostly because of the widening of the frontal squama, appears comparable with the Afro-European variation of the Middle Pleistocene (i.e., H. heidelbergensis/rhodesiensis). Taking into account the unique morphological pattern displayed by Ceprano, its role as a link between early Homo and the Middle Pleistocene populations of Europe and Africa is not falsified. Thus, when aspects of the Ceprano's morphology are described within the analytical framework provided by geometric morphometrics, the relationships between Ceprano and the subsequent Afro-European fossil record are emphasized, suggesting the occurrence of an ancestral stock of H. heidelbergensis/rhodesiensis that is properly represented by the Italian specimen. 相似文献
992.
Camilla Bernasconi Giorgio Volponi Claudia Picozzi Roberto Foschino 《Applied microbiology》2007,73(19):6321-6325
A quantitative real-time PCR targeting the tnaA gene was studied to detect Escherichia coli and distinguish E. coli from Shigella spp. These microorganisms revealed high similarity in the molecular organization of the tna operon. 相似文献
993.
Differences in osteoblast miRNA induced by cell binding domain of collagen and silicate-based synthetic bone 总被引:1,自引:0,他引:1
Palmieri A Pezzetti F Brunelli G Zollino I Scapoli L Martinelli M Arlotti M Carinci F 《Journal of biomedical science》2007,14(6):777-782
Summary PerioGlas (PG) is an silicate-based (i.e. anorganic) material used for grafting periodontal osseous defects since the ninety
whereas P-15 is an analog of the cell binding domain of collagen (i.e. organic material) that is successfully used in clinical
trial to promote bone formation. However, how PG (i.e anorganic material) and P-15 (i.e. collagen) differentially alter osteoblast
activity to promote bone formation is unknown. We therefore attempted to get more insight by using microRNA microarray techniques
to investigate the translation process in osteoblasts differentially exposed to PG and P-15. We identified 3 up-regulated
miRNA (i.e. mir-30b, mir-26a, mir-92) and 8 down-regulated miRNA (i.e. mir-337, mir-377, mir-25, mir-200b, mir-129, mir-373,
mir-133b, mir-489). The data reported are, to our knowledge, the first study on translation regulation in osteoblatsts differentially
exposed to cell binding domain of collagen and to silicate-based material. Both enhance the translation of several miRNA belonging
to osteogenetic genes, but P-15 acts preferentially on homeobox genes. 相似文献
994.
Cucco M Guasco B Malacarne G Ottonelli R 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2007,147(4):1038-1046
Carotenoids are important dietary constituents in birds. Their functions are numerous and complex, and breeding females are potentially faced with an optimal allocation of these resources between themselves and offspring. We conducted a dietary experiment (low and high supply of beta-carotene) to examine the effect of beta-carotene on health and immune response of 64 reproducing pairs of Grey Partridge (Perdix perdix L.) and on the quality of their eggs, as revealed by the measurement of biochemical components in yolk and albumen, the egg hatching rate and chick survival. We found a beneficial effect of beta-carotene on the erythrosedimentation rate and immune response of females (PHA reaction), while the diet did not significantly affect these variables in males. In both sexes, the plasma level of carotenoids was not related to the quantity of beta-carotene supplied. A higher quantity of beta-carotene in the diet did not induce a variation of egg nutrients (proteins and lipids), nor an increase of yolk beta-carotene concentration. We detected a higher concentration of lysozyme, an enzyme with antibacterial activity, in the albumen of eggs laid by females with a high supply of beta-carotene. These eggs showed higher hatching rates. The present study indicates that although carotenoid supplementation does not influence blood and yolk carotenoid levels, it results in better immune conditions of females, eventually translated into increased antibacterial activity of the eggs. The broad range of beneficial effects of carotenoids is discussed. 相似文献
995.
Stefano Benazzi Daniele Panetta Cinzia Fornai Michel Toussaint Giorgio Gruppioni Jean‐Jacques Hublin 《American journal of physical anthropology》2014,153(2):305-313
The study of enamel thickness has received considerable attention in regard to the taxonomic, phylogenetic and dietary assessment of human and non‐human primates. Recent developments based on two‐dimensional (2D) and three‐dimensional (3D) digital techniques have facilitated accurate analyses, preserving the original object from invasive procedures. Various digital protocols have been proposed. These include several procedures based on manual handling of the virtual models and technical shortcomings, which prevent other scholars from confidently reproducing the entire digital protocol. There is a compelling need for standard, reproducible, and well‐tailored protocols for the digital analysis of 2D and 3D dental enamel thickness. In this contribution we provide essential guidelines for the digital computation of 2D and 3D enamel thickness in hominoid molars, premolars, canines and incisors. We modify previous techniques suggested for 2D analysis and we develop a new approach for 3D analysis that can also be applied to premolars and anterior teeth. For each tooth class, the cervical line should be considered as the fundamental morphological feature both to isolate the crown from the root (for 3D analysis) and to define the direction of the cross‐sections (for 2D analysis). Am J Phys Anthropol 153:305–313, 2014. © 2013 Wiley Periodicals, Inc. 相似文献
996.
Paolo Armando Gagliardi Laura di Blasio Alberto Puliafito Giorgio Seano Roberto Sessa Federica Chianale Thomas Leung Federico Bussolino Luca Primo 《The Journal of cell biology》2014,206(3):415-434
Directional cell migration is of paramount importance in both physiological and pathological processes, such as development, wound healing, immune response, and cancer invasion. Here, we report that 3-phosphoinositide-dependent kinase 1 (PDK1) regulates epithelial directional migration and invasion by binding and activating myotonic dystrophy kinase–related CDC42-binding kinase α (MRCKα). We show that the effect of PDK1 on cell migration does not involve its kinase activity but instead relies on its ability to bind membrane phosphatidylinositol (3,4,5)-trisphosphate. Upon epidermal growth factor (EGF) stimulation, PDK1 and MRCKα colocalize at the cell membrane in lamellipodia. We demonstrate that PDK1 positively modulates MRCKα activity and drives its localization within lamellipodia. Likewise, the retraction phase of lamellipodia is controlled by PDK1 through an MRCKα-dependent mechanism. In summary, we discovered a functional pathway involving PDK1-mediated activation of MRCKα, which links EGF signaling to myosin contraction and directional migration. 相似文献
997.
Juliane Bentes Picanço Paulo Eduardo Raimann Giorgio Adriano Paskulin Luís Alvarez António Amorim Sidney Emanuel Batista dos Santos Clarice Sampaio Alho 《Gene》2014
Alleles at the TPOX STR locus have 6–14 different numbers of a four-nucleotide (AATG) repeat motif arranged in tandem. Although tri-allelic genotypes are generally rare, the TPOX tri-allelic pattern has a higher frequency, varying widely among populations. Despite this, there are few accurate reports to disclose the nature of the TPOX third allele. In this work we present data obtained from 45 individuals belonging to the same pedigree, in which there are cases of tri-allelic TPOX genotypes. The subjects were apparently healthy with a normal biological development. We noticed six tri-allelic cases in this family, and all of them were women. Karyotype analysis showed no occurrence of partial 2p trisomy. All the tri-allelic cases had the genotype 8–10–11, probably due to three copies of the TPOX STR sequence in all cells (Type 2 tri-allelic pattern). Based on previous data we assumed the allele 10 as the TPOX third allele. The pedigree analyses show evidences that the TPOX extra-allele was the allele10, it is placed far from the main TPOX locus, and that there is a potential linkage of the TPOX extra-allele-10 with Xq. This was the first study that included a large pedigree analysis in order to understand the nature TPOX tri-allelic pattern. 相似文献
998.
999.
Serena Buscone Werner Garavello Fabio Pagni Renato Maria Gaini Giorgio Cattoretti 《PloS one》2014,9(5)
Adenoidal tissue (also known as nasopharyngeal tonsils) of 58% of humans in the pediatric age group contains immature T-lymphoid cells with the phenotype of thymocytes (TdT+,CD1abc+, cytoplasmic CD3+, coexpressing CD4 and CD8, lacking an Intraepithelial Lymphocyte-associated phenotype). The notable difference in comparison to palatine tonsils is the clustering in groups and sheets, comprising hundreds or thousands of cells (1.7%±0.2 of total T cells). The thymic epithelium is morphologically and phenotypically absent. Adenoids share with tonsils and lymph nodes the presence of immature B cell precursors (TdT+, CD1a-, Pax5+, Surrogate light chain±), however in these latter the presence of TdT+, CD1a+, Pax5- precursors is absent or limited to individual cells. Human adenoids are distinct among the Waldeyer''s ring lymphoid tissue because of the known embryogenic derivation from the third pharyngeal pouch, from which the thymus develops; in addition, they may display phenotypic incomplete features of a vestigial thymus. 相似文献
1000.
Babs E. Verstrepen Herman Oostermeijer Zahra Fagrouch Melanie van Heteren Henk Niphuis Tom Haaksma Ivanela Kondova Willy M. Bogers Marina de Filette Niek Sanders Linda Stertman Sofia Magnusson Orsolya L?rincz Julianna Lisziewicz Luisa Barzon Giorgio Palù Michael S. Diamond Stefan Chabierski Sebastian Ulbert Ernst J. Verschoor 《PloS one》2014,9(11)
The mosquito-borne West Nile virus (WNV) causes human and animal disease with outbreaks in several parts of the world including North America, the Mediterranean countries, Central and East Europe, the Middle East, and Africa. Particularly in elderly people and individuals with an impaired immune system, infection with WNV can progress into a serious neuroinvasive disease. Currently, no treatment or vaccine is available to protect humans against infection or disease. The goal of this study was to develop a WNV-vaccine that is safe to use in these high-risk human target populations. We performed a vaccine efficacy study in non-human primates using the contemporary, pathogenic European WNV genotype 1a challenge strain, WNV-Ita09. Two vaccine strategies were evaluated in rhesus macaques (Macaca mulatta) using recombinant soluble WNV envelope (E) ectodomain adjuvanted with Matrix-M, either with or without DNA priming. The DNA priming immunization was performed with WNV-DermaVir nanoparticles. Both vaccination strategies successfully induced humoral and cellular immune responses that completely protected the macaques against the development of viremia. In addition, the vaccine was well tolerated by all animals. Overall, The WNV E protein adjuvanted with Matrix-M is a promising vaccine candidate for a non-infectious WNV vaccine for use in humans, including at-risk populations. 相似文献