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Judith Sealy - One of the best experts on this subject based on the ideXlab platform.
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Multi-tissue stable carbon and nitrogen isotope models for dietary reconstruction: Evaluation using a southern African farming population.
American journal of physical anthropology, 2018Co-Authors: Madeline Zhu, Judith SealyAbstract:Objectives Multi-tissue stable isotope models to reconstruct past diets (Froehle, Kellner, & Schoeninger, 2012; Kellner & Schoeninger, 2007) have lacked data from a heavily C4 -dependent population. Using new data from southern African agriculturalists, published models are evaluated for accuracy in dietary reconstruction and applicability to isotopically diverse diets. Additionally, isotopic variation between tooth enamel and Bone Apatite, which are often treated as isotopically equivalent, is investigated. Materials and methods δ13 CBone Apatite , δ13 Ctooth enamel , δ13 Ccollagen , and δ15 Ncollagen values for 51 adult southern African agriculturalists are presented. Bivariate (linear) and multivariate (cluster analysis, discriminant function analysis) models are recreated including these data, and the resulting dietary reconstructions evaluated against what we know of archaeological diets. Results Δ13 Ccollagen-enamel (5.67 ± 1.66‰) is significantly larger than Δ13 Ccollagen-Bone Apatite (4.77 ± 1.42‰) and are significantly different from each other (Mann Whitney U-Test, p = 0.0). δ13 CBone Apatite and δ13 Ctooth enamel were uncorrelated (R2 = 0.24). The agriculturalists consumed highly variable and heterogeneous diets, (mean δ13 CBone Apatite = -6.25 ± 2.49‰, δ13 Ctooth enamel = -2.88 ± 2.48‰, δ13 Ccollagen = -8.65 ± 2.16‰, δ15 Ncollagen = 10.05 ± 1.9‰). Multi- and bi-variate models under-estimate the probable contribution of C3 energy sources, and recreation of cluster analysis results in a significant reduction in the parsimony of the dietary clusters derived in Froehle et al., 2012. Conclusion Bone Apatite and tooth enamel are distinct biominerals, and their δ13 C values should not be treated as equivalent. Multiple tissue isotopes provide valuable insight into diet that cannot be achieved with single tissues, but current models are limited by the lack of isotopic diversity in the data on which they are based.
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Technical note: interpreting stable carbon isotopes in human tooth enamel: an examination of tissue spacings from South Africa.
American journal of physical anthropology, 2012Co-Authors: Emma Loftus, Judith SealyAbstract:Stable isotope analysis of skeletal tissues is widely used in archeology and paleoanthropology to reconstruct diet. In material that is poorly preserved or very old, the tissue of choice is frequently tooth enamel, since this is less susceptible to diagenesis. The relationships between carbon isotope ratios in tooth enamel (δ(13) C(enamel) ), Bone collagen (δ(13) C(collagen) ), and Bone Apatite (δ(13) C(Bone Apatite) ) are, however, not well understood. To elucidate these, we have measured all three indicators in archeological humans from the western and southern Cape coastal regions of South Africa. The correlation between δ(13) C(enamel) and δ(13) C(collagen) is good (R(2) = 0.71 if two outliers are excluded, n = 79). The correlation between δ(13) C(enamel) and δ(13) C(Bone Apatite) is weaker (R(2) = 0.37, n = 33) possibly due to Bone diagenesis. No systematic offset between δ(13) C(Bone Apatite) and δ(13) C(enamel) was observed in this sample of archeological humans. Intertooth comparisons of δ(13) C(enamel) in three individuals showed little variation, despite the different ages of crown formation. Carbon isotope ratios in both enamel and Bone collagen are good proxies for δ(13) C(diet) .
Antoine Zazzo - One of the best experts on this subject based on the ideXlab platform.
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A revised radiocarbon chronology of the aceramic shell midden of Ra's al-Hamra 6 (Muscat, Sultanate of Oman): implication for occupational sequence, marine reservoir, and human mobility
Radiocarbon, 2016Co-Authors: Antoine Zazzo, Olivia Munoz, Emilie Badel, Irène Béguier, Francesco Genchi, Lapo Gianni MarcucciAbstract:Ra's al-Hamra 6 (RH-6) is one of the earliest stratified archaeological sites along the eastern littoral of the Arabian Peninsula. This shell midden was radiocarbon dated to the 6th–5th millennium cal BC, but the majority of the dates were obtained before the advent of accelerator mass spectrometry (AMS) 14 C dating and suffer from large uncertainties. In addition, most of these dates were obtained on marine and mangrove shells and required correction for local variations from the global average marine 14 C reservoir age (MRA). This proved difficult because no consensus value exists for this period in the area. Recent excavations at RH-6 offered the opportunity to redate this important site in order to precisely determine its occupation history and later use as a graveyard, and establish the marine reservoir effect for this time period. Thirty-eight samples of charcoal, shells, and human Bone Apatite were selected for 14 C dating. Bayesian modeling of the 14 C dates suggests that the formation of the shell midden spanned ~1 millennium, between the mid-6th and the mid-5th millennium cal BC. Positive and consistent ΔR values were calculated throughout the entire sequence, ranging from 99 ± 27 to 207 ± 43 14 C yr. At the beginning of the 4th millennium cal BC, RH-6 was used as a graveyard, as suggested by the 14 C dating of a shell in strict association with an individual buried at the surface of the site. 14 C dating of human Bone Apatite allowed us to calculate that 89% of this individual's diet derived from marine resources. This finding confirms previous observations showing the overwhelming presence of marine and mangrove-dwelling species in the faunal and charcoal assemblage, and implies a low mobility, or mobility restricted to the coast for this population during the 4th millennium cal BC.
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Bone and enamel carbonate diagenesis a radiocarbon prospective
Palaeogeography Palaeoclimatology Palaeoecology, 2014Co-Authors: Antoine ZazzoAbstract:Abstract The debate regarding the susceptibility of Bone and enamel carbonate to preserve in vivo carbon isotope ratios is as old as paleodietary research. After more than three decades of controversy, a consensus seems to have been reached, and archeological Bone Apatite is generally considered suitable while enamel has become the gold standard for pre-Quaternary studies. But the absence of a quantitative diagenetic test to assess the preservation of Bone and enamel carbonate δ13C values is problematic. Here, radiocarbon (14C) dating is used as a tracer, to quantify carbon isotope exchange in Bone, dentine and enamel carbonate during early diagenesis. Samples covering most of the range of radiocarbon dating and coming from different burial environments and climates were dated. When possible, enamel, dentine and Bone from the same individuals were selected. All tissues record an uptake of modern carbon leading to a change in the radiocarbon age of the sample which becomes significant after about 8000 BP. In some of the sites, enamel is older than Bone or dentine carbonate from the same individual, while in others, the contrary is observed. An intermediate case where identical 14C ages were measured between Bone carbonate and enamel was also observed, suggesting either a lack of alteration, or similar degree of C-isotope exchange for the two tissues. Overall, no systematic 14C difference was found between Bone, dentine and enamel from the same individual suggesting that differences in crystallinity or porosity do not play a major role during the early stage of Bone and enamel diagenesis and that δ13C values measured in Bone Apatite are as reliable as in enamel at least for the past 40,000 yr.
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diet and mobility in a late neolithic population of coastal oman inferred from radiocarbon dating and stable isotope analysis
American Journal of Physical Anthropology, 2014Co-Authors: Antoine Zazzo, Olivia Munoz, Jeanfrancois SaliegeAbstract:† deceased ABSTRACT In Oman, the presence of highly produc- tive marine environments, coupled with relatively lim- ited land resources, have led to intense exploitation of coastal resources, but the question of the seasonality of occupation of coastal sites remains open. Our aim is to evaluate the contribution of marine resources to the diet of the Neolithic population of Ra's al-Hamra 5 (RH-5) to shed new light on its mobility, using stable isotopes and radiocarbon ( 14 C) dating as dietary tracers. Charcoal, shell, human Bone and enamel Apatite from eight con- temporary graves were sampled. Graves are thought to provide the best chance to obtain marine and terrestrial remains that were contemporary with the human remains in order to calculate the marine reservoir effect (MRE) for this period. Inter-individual variation in human Bone Apatite d 13 C value is small, suggesting a homogenous diet. Bone Apatite 14 C ages are very close to the shell ages while enamel is significantly younger and plots near the charcoal ages. Older enamel ages were obtained when a stronger acetic treatment was used, demonstrating that the young ages are due to diagenetic alteration rather than a diachronic change in diet and that only Bone Apatite retained in vivo dietary signals. Bone ages indicate a heavy reliance on marine resources and it is therefore unlikely that the individuals analyzed here were leaving the coast seasonally, although mobility along the coast cannot be excluded. Am J Phys Anthro- pol 000:000-000, 2013. V C 2013 Wiley Periodicals, Inc.
Min Guan - One of the best experts on this subject based on the ideXlab platform.
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runx2 osterix and zinc uptake synergize to orchestrate osteogenic differentiation and citrate containing Bone Apatite formation
Advanced Science, 2018Co-Authors: Tongling Huang, Meng Yang, Qingli Liu, Haobo Pan, Huaiyu Wang, Junfeng Wang, Min GuanAbstract:Citrate is essential to biomineralization of the Bone especially as an integral part of Apatite nanocomposite. Citrate precipitate of Apatite is hypothesized to be derived from mesenchymal stem/stromal cells (MSCs) upon differentiation into mature osteoblasts. Based on 13C-labeled signals identified by solid-state multinuclear magnetic resonance analysis, boosted mitochondrial activity and carbon-source replenishment of tricarboxylic acid cycle intermediates coordinate to feed forward mitochondrial anabolism and deposition of citrate. Moreover, zinc (Zn2+) is identified playing dual functions: (i) Zn2+ influx is influenced by ZIP1 which is regulated by Runx2 and Osterix to form a zinc-Runx2/Osterix-ZIP1 regulation axis promoting osteogenic differentiation; (ii) Zn2+ enhances citrate accumulation and deposition in Bone Apatite. Furthermore, age-related Bone loss is associated with Zn2+ and citrate homeostasis; whereas, restoration of Zn2+ uptake alleviates age-associated declining osteogenic capacity and amount of citrate deposition. Together, these results indicate that citrate is not only a key metabolic intermediate meeting the emerging energy demand of differentiating MSCs but also participates in extracellular matrix mineralization, providing mechanistic insight into Zn2+ homeostasis and Bone formation.
Michele Bianchi - One of the best experts on this subject based on the ideXlab platform.
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Fabrication and characterization of biomimetic hydroxyApatite thin films for Bone implants by direct ablation of a biogenic source
Materials Science and Engineering: C, 2019Co-Authors: Gabriela Graziani, Matteo Berni, Monica De Carolis, Alfonso Gambardella, Gianluca Carnevale, Maria Cristina Maltarello, Michele BianchiAbstract:Abstract Biomimetic Bone Apatite coatings were realized for the first time by the novel Ionized Jet Deposition technique. Bone coatings were deposited on titanium alloy substrates by pulsed electron ablation of deproteinized bovine Bone shafts in order to resemble Bone Apatite as closely as possible. The composition, morphology and mechanical properties of the coatings were characterized by GI-XRD, FT-IR, SEM-EDS, AFM, contact angle measurements, micro-scratch and screw-insertion tests. Different post-treatment annealing conditions (from 350 °C to 425 °C) were investigated. Bone Apatite coatings exhibited a nanostructured surface morphology and a composition closely resembling that of the deposition target (i.e. natural Bone Apatite), also regarding the presence of magnesium and sodium ions. Crystallinity and composition of the coatings were strongly influenced by annealing temperature and duration; in particular, upon annealing at 400 °C and above, a crystallinity similar to that of Bone was achieved. Finally, adhesion to the titanium substrate and hydrophilicity were significantly enhanced upon annealing, all characteristics being known to have a strong positive impact on promoting host cells attachment, proliferation and differentiation.
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Corrigendum to "Osteogenic Differentiation of hDPSCs on Biogenic Bone Apatite Thin Films".
Stem cells international, 2017Co-Authors: Michele Bianchi, Matteo Berni, Alessandra Pisciotta, Andrea Visani, Laura Bertoni, Alessandro Russo, A. Gambardella, Anto De Pol, Gianluca CarnevaleAbstract:[This corrects the article DOI: 10.1155/2017/3579283.].
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Osteogenic Differentiation of hDPSCs on Biogenic Bone Apatite Thin Films
Stem Cells International, 2017Co-Authors: Michele Bianchi, Matteo Berni, Alessandra Pisciotta, Alfonso Gambardella, Andrea Visani, Laura Bertoni, Alessandro Russo, Gianluca CarnevaleAbstract:A previous study reported the structural characterization of biogenic Apatite (BAp) thin films realized by a pulsed electron deposition system by ablation of deproteinized bovine Bone. Thin films annealed at 400°C exhibited composition and crystallinity degree very close to those of biogenic Apatite; this affinity is crucial for obtaining faster osseointegration compared to conventional, thick hydroxyApatite (HA) coatings, for both orthopedics and dentistry. Here, we investigated the adhesion, proliferation, and osteogenic differentiation of human dental pulp stem cells (hDPCS) on as-deposited and heat-treated BAp and stoichiometric HA. First, we showed that heat-treated BAp films can significantly promote hDPSC adhesion and proliferation. Moreover, hDPSCs, while initially maintaining the typical fibroblast-like morphology and stemness surface markers, later started expressing osteogenic markers such as Runx-2 and OSX. Noteworthy, when cultured in an osteogenic medium on annealed BAp films, hDPSCs were also able to reach a more mature and terminal commitment, with respect to HA and as-deposited films. Our findings suggest that annealed BAp films not only preserve the typical biological properties of stemness of, hDPSCs but also improve their ability of osteogenic commitment.
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Plasma-assisted deposition of Bone Apatite-like thin films from natural Apatite
Materials Letters, 2017Co-Authors: Michele Bianchi, Devis Bellucci, Matteo Berni, Gregorio Marchiori, Alfonso Gambardella, Gabriela Graziani, Maria Cristina Maltarello, Fabiola Liscio, Francesco ValleAbstract:Abstract In orthopedics and dentistry, novel approaches for fabricating biomimetic and mechanically robust bioactive coatings are highly desirable in order to truly improve the clinical results of coated implants compared to uncoated ones. In this paper, a biological-like Apatite coating is deposited for the first time by plasma-assisted deposition of a natural Apatite source. Specifically, we deposited Bone Apatite-like (BAL) thin films from Bone Apatite targets by pulsed electron deposition (PED). Morphology, composition, structure and mechanical properties of as-deposited and annealed BAL and stoichiometric hydroxyApatite (HA) films were investigated. While as-deposited BAL and HA films were poorly crystalline at room temperature, they crystallized to an extent very close to that of natural Apatite when annealed at 400 °C. In addition, FTIR analysis pointed out that BAL films closely resembled the composition of the starting natural Apatite target. Finally, nanoindentation tests indicated that BAL films with high mechanical properties could be deposited by PED.
Yubo Fan - One of the best experts on this subject based on the ideXlab platform.
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Shear-mediated orientational mineralization of Bone Apatite on collagen fibrils.
Journal of materials chemistry. B, 2017Co-Authors: Xufeng Niu, Qingling Feng, Rui Fan, Guo Xiaolin, Zuo Yang, Yubo FanAbstract:Fluid shear stress (FSS) is regarded as a predominant stimulus to Bone cells and matrix under physiological conditions. The influence of FSS on mineralization of collagen is explored by exposure to an environment of constant FSS values less than 2.0 Pa. At the designated time points, the Apatite/collagen composites were characterized by X-ray diffraction, calcium/phosphorus assay, differential scanning calorimetry, transmission electron microscopy, and selected area electron diffraction. The results show that FSS within a certain range, especially within 1.5 Pa, has a positive effect on collagen mineralization, as illustrated by the enhanced degree of collagen self-assembly, accelerated speed of amorphous calcium phosphate (ACP) formation and transition, and well-organized Apatite structure and orientation. Under the condition of FSS, the size of ACP is also well controlled, and the minerals disperse inside collagen fibrils; this leads to intrafibrillar mineralization. These findings are helpful for understanding the mechanism of mineralization in natural Bone tissue and deepen the knowledge of biomechanics of this process.
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Shear-mediated crystallization from amorphous calcium phosphate to Bone Apatite.
Journal of the mechanical behavior of biomedical materials, 2015Co-Authors: Xufeng Niu, Liyang Wang, Feng Tian, Lizhen Wang, Qingling Feng, Yubo FanAbstract:The contribution of fluid shear stress (FSS) on the conversion of amorphous calcium phosphate (ACP) to Bone Apatite is investigated. The ACP precursors are prepared by using a wet-chemistry method and further exposed to the constant FSS environment with values of 0.5, 1.0, 1.5, and 2.0Pa. At the designated time points, the Apatites are characterized by transmission electron microscopy, X-ray diffraction, and inductively coupled plasma-mass spectroscopy. The results show that, the low FSS (≤1.0Pa) has positive effects on the transition of ACP, characterized by the accelerated crystallization velocity and the well-organized calcium-deficient hydroxyApatite (CDHA) structure, whereas the high FSS (>1.0Pa) has negative effects on this conversion process, characterized by the poor CDHA crystal morphologies and the destroyed structures. The bioactivity evaluations further reveal that, compared with the FSS-free group, the CDHA prepared under 1.0Pa FSS for 9h presents the more biocompatible features with pre-osteoblast cells. These results are helpful for understanding the mechanism of Apatite deposition in natural Bone tissue.