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1.
Forensic Sci Int ; 306: 110056, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31765883

RESUMO

The killings during the Second World War, with nearly one hundred thousand victims, is one of the greatest losses of life in Slovenia's modern history. This article presents the genetic identification of the victims of the largest family massacre that occurred in Slovenia, in which 10 members of the same family were killed. Seven of them were buried in a hidden mass grave and only two children survived. In 2015 and 2016, two graves were found and three incomplete female skeletons and at least three incomplete male skeletons were exhumed. A total of 12 bones and teeth were analysed and compared to two living relatives. Extracted DNA was quantified using the PowerQuant kit, and various autosomal and Y-STR kits were used for STR typing. Up to 2.7 ng DNA/g of powder was acquired from the samples analysed. We managed to obtain nuclear DNA for successful STR typing from seven bones and one molar. From the female grave, autosomal profiles were obtained only from one skeleton, and from the male grave from five out of six femurs. The relationships between the males were additionally confirmed by analyses of Y-STRs. STR profiles made possible the identification of four family members; one of the aunts from the female grave, and two uncles and the father of the surviving children, who were used as family references, from the male grave. The product rule was used to calculate a combined likelihood ratio for autosomal and Y-STRs, and statistical analyses showed high confidence of correct identification with posterior probability (PP) greater than 99.9 % for three out of four victims identified. For identifying the aunt, the PP obtained after ESI-17 and NGM STR typing was too low. To increase the PP, the next-generation sequencing Precision ID GlobalFiler NGS STR Panel was used and, after the analysis of additional STR loci, the statistical analysis showed a PP greater than 99.9 %, indicating that a sufficient number of genetic markers had been investigated in identifying the skeletal remains of the aunt. An elimination database containing the genetic profiles of all individuals that had been in contact with the bones was created to ensure traceability in case of contamination, and no matches were found. After more than 70 years, the skeletal remains were returned to the surviving children, who buried their relatives in a family grave.


Assuntos
Osso e Ossos/química , Impressões Digitais de DNA , Família , Dente/química , Restos Mortais , Sepultamento , Cromossomos Humanos Y , DNA/isolamento & purificação , Exumação , Feminino , Genética Forense , Sequenciamento de Nucleotídeos em Larga Escala , História do Século XX , Humanos , Masculino , Repetições de Microssatélites , Linhagem , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Eslovênia , II Guerra Mundial
2.
Anal Bioanal Chem ; 412(1): 27-36, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31705221

RESUMO

Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and laser-induced breakdown spectroscopy (LIBS) are widely accepted techniques for direct sampling of biological materials for elemental analysis, with increasing applications being reported over the recent years. This review is focused on the calibration materials used to quantify trace elements in different biological samples such as soft tissues (for instance brain, liver, hair) and hard tissues (bones and teeth). The design of a correct calibration strategy relies on the choice of an adapted reference material that can be commercially available or prepared in-house, which will be reviewed here. A large variety of methods has been approached and considered promising over the years, and the development of matrix-matched reference biological materials seems now closer than ever and gives hope to even better quantitation using LIBS and LA-ICP-MS.


Assuntos
Espectrometria de Massas/métodos , Oligoelementos/análise , Osso e Ossos/química , Encéfalo/metabolismo , Calibragem , Cabelo/química , Humanos , Fígado/química , Padrões de Referência , Dente/química , Oligoelementos/normas
3.
Mater Sci Eng C Mater Biol Appl ; 105: 110061, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546361

RESUMO

A technique for tooth surface modification with biocompatible calcium phosphate (CaP) has huge potential in dental applications. Recently, we achieved a facile and area-specific CaP coating on artificial materials by a laser-assisted biomimetic process (LAB process), which consists of pulsed laser irradiation in a supersaturated CaP solution. In this study, we induced the rapid biomineralization on the surface of human dentin by using the LAB process. A human dentin substrate was immersed in a supersaturated CaP solution, then its surface was irradiated with weak pulsed laser light for 30 min (LAB process). Ultrastructural analyses revealed that the pristine substrate had a demineralized collagenous layer on its surface due to the previous EDTA surface cleaning. After the LAB process, this collagenous layer disappeared and was replaced with a submicron-thick hydroxyapatite layer. We believe that the laser irradiation induced pseudo-biomineralization through the laser ablation of the collagenous layer, followed by CaP nucleation and growth at the dentin-liquid interface. The mineralized layer on the dentin substrate consisted of needle-like hydroxyapatite nanocrystals, whose c-axes were weakly oriented along the direction perpendicular to the substrate surface. This LAB process would offer a new tool enabling tooth surface modification and functionalization through the in situ pseudo-biomineralization.


Assuntos
Dentina/citologia , Durapatita/química , Lasers , Dente/química , Humanos , Propriedades de Superfície
4.
Forensic Sci Int Genet ; 42: 181-189, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31374457

RESUMO

Forensic and population genetics often rely on Y-chromosomal studies. Whether it is a human identification case, trace evidence examination or phylogenetic analysis, a Y-STR haplotype is an important tool in the hands of law enforcement agencies. A common obstacle in achieving satisfactory results in all of the above mentioned circumstances, is low DNA quantity and quality within samples obtained. In this study we have examined Y-STR haplotypes in 75 bone material samples, coming from different time periods. For this purpose we have chosen YFiler Plus PCR Amplification Kit (ThermoFisher Scientific) and ForenSeq Signature DNA Prep Kit (Verogen Inc.), which use two different allele calling technologies - capillary electrophoresis and Massively Parallel Sequencing respectively. Full profiles were obtained from DNA extracts with as little as 0.1896 ng (Degradation Index 1.3) (ForenSeq) and 0.0591 ng (Degradation Index 26.8) (YFiler Plus) DNA input. The results that we present in this paper show differences in amplification rates between common markers in both kits. The differences strictly reflect mean amplicon length of markers. This, however, does not seem to influence Y-haplogroup estimation results noticeably. In one sample a discordance occurred between haplotypes obtained with both methods, where a 24 allele was called in DYS390 marker by capillary electrophoresis, while for the same sample in this locus a 23 allele was shown with MPS. A reason for this is yet to be investigated. The sequence analysis revealed a significant variation between isometric alleles, especially within repetitive regions of studied Y-STR markers.


Assuntos
Cromossomos Humanos Y , Degradação Necrótica do DNA , Impressões Digitais de DNA , Haplótipos , Reação em Cadeia da Polimerase/métodos , Osso e Ossos/química , Eletroforese Capilar , Genética Forense/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Repetições de Microssatélites , Análise de Sequência de DNA , Dente/química
5.
Forensic Sci Int Genet ; 42: 268-274, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31442669

RESUMO

In 1998, a Viking Age mass grave was discovered and excavated at St. Laurence´s churchyard in Sigtuna, Sweden. The excavated bones underwent osteoarchaeological analysis and were assigned to at least 19 individuals. Eleven skeletons showed sharp force trauma from bladed weapons. Mass graves are an unusual finding from this time period, making the burial context extraordinary. To investigate a possible maternal kinship among the individuals, bones and teeth from the skeletal remains were selected for mitochondrial DNA (mtDNA) analysis. Sanger sequencing of short stretches of the hypervariable segments I and II (HVS-I and HVS-II) was performed. A subset of the samples was also analysed by massively parallel sequencing analysis (MPS) of the entire mtDNA genome using the Precision ID mtDNA Whole Genome Panel. A total of 15 unique and three shared mtDNA profiles were obtained. Based on a combination of genetic and archaeological data, we conclude that a minimum of 20 individuals was buried in the mass grave. The majority of the individuals were not maternally related. However, two possible pairs of siblings or mother-child relationships were identified. All individuals were assigned to West Eurasian haplogroups, with a predominance of haplogroup H. Although the remains showed an advanced level of DNA degradation, the combined use of Sanger sequencing and MPS with the Precision ID mtDNA Whole Genome Panel revealed at least partial mtDNA data for all samples.


Assuntos
Restos Mortais , Sepultamento , Impressões Digitais de DNA , DNA Mitocondrial/genética , Adolescente , Adulto , Osso e Ossos/química , Criança , Feminino , Genoma Humano , Haplótipos , Sequenciamento de Nucleotídeos em Larga Escala , História Medieval , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência de DNA , Suécia , Dente/química , Adulto Jovem
6.
J Forensic Leg Med ; 67: 24-27, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31377682

RESUMO

BACKGROUND: A mass grave is any site that containing two or more associated corpses, at random or on purpose placed, of people who have died as a result of extra-judicial or random executions, not including those people who have died from armed confrontations or known major catastrophes. CASE PRESENTATION: The purpose of this paper is to explain how to reconstruct a biological profile of decomposed or skeletonized bodies and clarify the efforts done by the Libyan scientist after 2011 revolution and to set a reference for other researcher. The alleged location of the grave, as well as the alleged number and identities of the persons buried in the grave were obtained exclusively from witnesses' and relatives' testimonies. CONCLUSION: As the testimonies said, the grave was located at the alleged location and seven skeletons were exhumed. Also, the osteological and DNA study made investigators to identify the exhumed skeletons. And the dental analysis support the identification of a seven man alleged to have been buried in the grave, 7 victims were discovered.


Assuntos
Osso e Ossos/patologia , Impressões Digitais de DNA , Exumação , Adulto , Determinação da Idade pelo Esqueleto , Sepultamento , DNA/isolamento & purificação , Antropologia Forense , Odontologia Legal , Humanos , Líbia , Masculino , Repetições de Microssatélites , Determinação do Sexo pelo Esqueleto , Dente/química , Guerra
7.
Nature ; 572(7767): 112-115, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31308534

RESUMO

Reconstructing the detailed dietary behaviour of extinct hominins is challenging1-particularly for a species such as Australopithecus africanus, which has a highly variable dental morphology that suggests a broad diet2,3. The dietary responses of extinct hominins to seasonal fluctuations in food availability are poorly understood, and nursing behaviours even less so; most of the direct information currently available has been obtained from high-resolution trace-element geochemical analysis of Homo sapiens (both modern and fossil), Homo neanderthalensis4 and living apes5. Here we apply high-resolution trace-element analysis to two A. africanus specimens from Sterkfontein Member 4 (South Africa), dated to 2.6-2.1 million years ago. Elemental signals indicate that A. africanus infants predominantly consumed breast milk for the first year after birth. A cyclical elemental pattern observed following the nursing sequence-comparable to the seasonal dietary signal that is seen in contemporary wild primates and other mammals-indicates irregular food availability. These results are supported by isotopic evidence for a geographical range that was dominated by nutritionally depauperate areas. Cyclical accumulation of lithium in A. africanus teeth also corroborates the idea that their range was characterized by fluctuating resources, and that they possessed physiological adaptations to this instability. This study provides insights into the dietary cycles and ecological behaviours of A. africanus in response to food availability, including the potential cyclical resurgence of milk intake during times of nutritional challenge (as observed in modern wild orangutans5). The geochemical findings for these teeth reinforce the unique place of A. africanus in the fossil record, and indicate dietary stress in specimens that date to shortly before the extinction of Australopithecus in South Africa about two million years ago.


Assuntos
Fósseis , Hominidae , Estações do Ano , Estresse Fisiológico , Dente/química , Animais , Aleitamento Materno , Hominidae/anatomia & histologia , Hominidae/fisiologia , Pongo , Dente/anatomia & histologia , Dente/fisiologia
9.
Ann Hum Biol ; 46(5): 388-392, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31274338

RESUMO

Background: Endemic fluorosis induced by high concentrations of fluoride in groundwater and soils is a major health problem in several countries, particularly in volcanic areas.Aim: To evaluate the occurrence of dental fluorosis resulting from exposure to high levels of environmental fluoride in 79 AD Herculaneum and close Vesuvius towns.Subjects and methods: The occurrence of dental fluorosis from teeth of the Herculaneum victims of the 79 AD eruption and some individuals from Pompeii (14-37 AD) and Nocera Inferiore (Salerno, IV sec. AD) was detected by means of Particle Induced Gamma-ray Emission technique (PIGE).Results: A clinical and analytical scenario of dental fluorosis resulted from the extreme high fluorine tooth content detected in teeth from Herculaneum and the Vesuvius area inhabitants. The adoption of PIGE technique has proved to be particularly effective in showing moderate as well as milder forms of dental fluorosis, otherwise not clearly detectable by clinical and histological analysis.Conclusions: Morphological, histological and elemental analysis of teeth of the 79 AD Herculaneum population show that in this area fluorosis occurred since Roman times.


Assuntos
Fluorose Dentária/história , Dente/química , Fluorose Dentária/etiologia , História Antiga , Humanos , Itália , Pessoa de Meia-Idade , Erupções Vulcânicas/história
10.
J Forensic Sci ; 64(6): 1646-1657, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31343733

RESUMO

Between 1990 and 2018, the Defense POW/MIA Accounting Agency submitted 2177 cranial elements and 1565 teeth to the Armed Forces Medical Examiner System-Armed Forces DNA Identification Laboratory for DNA testing. In an effort to identify missing United States service members, materials were recovered from wartime losses inclusive of World War II, the Korean War, and Southeast Asia. Using four different DNA extraction protocols, DNA testing was performed using mitochondrial DNA Sanger sequencing, modified AmpFlSTR® Yfiler™, AmpFlSTR® MiniFiler™, PowerPlex® Fusion, or Next Generation Sequencing. This paper aims to provide optimal strategies for the DNA testing of skeletonized cranial materials. Cranial elements produced the most consistent results in Sanger sequencing using an organic purification; however, teeth were most successful for the same platform with an inorganic purification. The inverse is true for STR testing of cranial bones. Of the cranial elements, the temporal provided the most consistent results.


Assuntos
Impressões Digitais de DNA/métodos , DNA Mitocondrial/isolamento & purificação , Crânio/química , Dente/química , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Repetições de Microssatélites , Militares , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Manejo de Espécimes/métodos
11.
Amino Acids ; 51(8): 1233-1240, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31197572

RESUMO

The aim of this study was to evaluate the effect of spreading the lipopeptide surfactin, for short time (10/20 s), on dentin wettability. Study groups were surfactin: 2.8; 1.4; 0.7; 0.35; and 0.175 mg/mL and a control group that received no treatment. Dentin discs (4 mm height) were prepared and polished with 600-grit SiC paper. Contact angle determinations were carried out after microbrush spreading of surfactin on dentin specimens for, respectively, 10 and 20 s. Excess liquid was removed, and after 60 s, the specimens were analyzed in a goniometer using the sessile drop method to measure the contact angle. Results were analyzed by two-way ANOVA (concentration × time) and t student, with α = 0.05. Lower contact angles were obtained for surfactin (0.7 mg/mL) spread for 10 s. However, no statistical difference was observed for surfactin (2.8 mg/mL) applied during 20 s. Higher contact angles were observed for surfactin (0.7 mg/mL) spread for 20 s. In conclusion, dentin wettability is dependent on spreading time and surfactin concentration.


Assuntos
Dentina/química , Lipopeptídeos/administração & dosagem , Peptídeos Cíclicos/administração & dosagem , Dente/química , Molhabilidade/efeitos dos fármacos , Dentina/efeitos dos fármacos , Humanos , Teste de Materiais , Propriedades de Superfície
13.
Microsc Res Tech ; 82(9): 1489-1499, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31150562

RESUMO

The present study aims to evaluate the effect of brushing with fluoride dentifrice on teeth severely affected by erosion due to respiratory medicaments. Enamel (n = 50) and dentin (n = 50) bovine specimens were prepared and treated with artificial saliva (S-control), acebrofilin hydrochloride (AC), ambroxol hydrochloride (AM), bromhexine hydrochloride (BR), and salbutamol sulfate (SS) and subjected to cycles of demineralization (immersing in 3 mL, 1 min, three times a day at intervals of 1 hr, for 5 days) followed by remineralization (saliva, 37°C, 1 hr). Simulated brushing with fluoridated toothpaste was performed using 810 strokes in a reciprocal-action brushing simulator. Scanning electron microscopy, micro energy dispersive X-ray fluorescence (µ-EDXRF) spectroscopy and attenuated total reflection Fourier transform infrared (ATR FTIR) spectroscopy were then performed. µ-EDXRF images showed extensive erosion after treatment with all medicaments. SEM images showed enamel erosion in order SS > BR > AC = AM > S after brushing and fluoridation. FTIR results were in agreement. In case of dentin, µ-EDXRF measurements showed significant difference in mineral content (percent weight of calcium and phosphate) in SS + brushing + fluoridation treated enamel compared to control, while µ-EDXRF images showed erosive effects in the order SS > AM>BR > AC = S post brushing + fluoridation. SEM images showed erosion in the order SS > AM = BR > AC > S post brushing + fluoridation. Again, FTIR multivariate results were in agreement. Overall, our study shows that proper oral care is critical when taking certain medication. The study also demonstrates the possible use of FTIR for rapid clinical monitoring of tooth erosion in clinics.


Assuntos
Broncodilatadores/efeitos adversos , Microscopia Eletrônica de Varredura , Espectrometria por Raios X , Espectrofotometria Infravermelho , Desmineralização do Dente/induzido quimicamente , Dente/efeitos dos fármacos , Animais , Bovinos , Esmalte Dentário/química , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/ultraestrutura , Dentina/química , Dentina/efeitos dos fármacos , Dentina/ultraestrutura , Dente/química , Dente/ultraestrutura
14.
Forensic Sci Int Genet ; 42: 39-44, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31216503

RESUMO

Measuring the quantity of DNA present in a forensic sample is relevant in a number of ways. First, it informs the analyst about the general DNA content to adjust the volume of DNA extract used for the genotyping assay to the optimal conditions (when possible). Second, quantification values can serve as plausibility checks for the performance of the DNA extraction method used as extraction positive and negative controls demand expected values. Third and relevant to highly compromised specimens, DNA quantification can inform about the degradation state of the DNA extracted from the unknown biological sample and aid the choice of downstream genotyping assays. While there are different, commercial products for the quantification of nuclear DNA available, commercial mitochondrial DNA (mtDNA) quantification systems are rare. Even more so, the simultaneous quantification of nuclear and mtDNA that is of relevance in highly degraded forensic specimens has rarely been described. We present here a novel real-time qPCR based tetraplex system termed SD quants that targets two different-sized mtDNA and a nuclear DNA region and includes an internal positive control to monitor potential inhibition. SD quants was compared to other existing quantification systems and subjected to analysis of severely degraded DNA present in ancient DNA and aged forensic specimens. This study complies with the MIQE (Bustin et al., 2009) guidelines (when applicable).


Assuntos
Núcleo Celular/genética , Degradação Necrótica do DNA , Impressões Digitais de DNA , DNA Mitocondrial/análise , DNA/análise , Reação em Cadeia da Polimerase em Tempo Real/métodos , Osso e Ossos/química , Cabelo/química , Humanos , Dente/química
15.
PLoS One ; 14(4): e0214925, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30943255

RESUMO

Neanderthals had complex land use patterns, adapting to diversified landscapes and climates. Over the past decade, considerable progress has been made in reconstructing the chronology, land use and subsistence patterns, and occupation types of sites in the Rhône Valley, southeast France. In this study, Neanderthal mobility at the site of Payre is investigated by combining information from lithic procurement analysis ("chaîne evolutive" and "chaîne opératoire" concepts) and strontium isotope analysis of teeth (childhood foraging area), from two units (F and G). Both units date to the transition from Marine Isotope Stage (MIS) 8 to MIS 7, and show similar environmental conditions, but represent contrasting occupation durations. Level Gb (unit G) represents a long-term year-round use, in contrast to short-term seasonal use of the cave in level Fb (unit F). For both levels, lithic material and food were generally collected from a local to semi-local region. However, in level Gb, lithic materials were mainly collected from colluviums and food collected in the valley, whereas in level Fb, lithic procurement focused primarily on alluvial deposits and food was collected from higher elevation plateaus. These procurement or exchange patterns might be related to flint availability, knapping advantages of alluvial flint or occupation duration. The site of Payre is located in a flint rich circulation corridor and the movement of groups or exchanges between groups were organized along a north-south axis on the plateaus or towards the east following the river. The ridges were widely used as they are rich in flint, whereas the Rhône Valley is not an important source of lithic raw materials. Compared to other western European Middle Palaeolithic sites, these results indicate that procurement strategies have a moderate link with occupation types and duration, and with lithic technology. The Sr isotope ratios broadly match the proposed foraging areas, with the Rhône Valley being predominantly used in unit G and the ridges and limestone plateaus in unit F. While lithic reconstructions and childhood foraging are not directly related this suggests that the three analysed Neanderthals spend their childhood in the same general area and supports the idea of mobile Neanderthals in the Rhône Valley and neighbouring higher elevation plateaus. The combination of reconstructing lithic raw material sources, provisioning strategies, and strontium isotope analyses provides new details on how Neanderthals at Payre practised land use and mobility in the Early Middle Palaeolithic.


Assuntos
Arqueologia , Clima , Fósseis , Homem de Neandertal , Isótopos de Estrôncio/análise , Dente , Animais , França , Homem de Neandertal/anatomia & histologia , Homem de Neandertal/metabolismo , Dente/anatomia & histologia , Dente/química , Dente/metabolismo
16.
J Med Syst ; 43(4): 97, 2019 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-30868440

RESUMO

The application of tribology in dentistry is growing rapidly, intense research has been conducted to develop an understanding of dental tribology for better selection of artificial materials and dental implant design. Dental biotribology, has been one of the most important branches in biotribology in recent years. The aim of this research is to investigate the tribological performances in the tooth-to-tooth contact and material-to-natural tooth contact (zirconia vs. zirconia and natural tooth vs. zirconia). The presented research was carried out by testing the above mentioned tribological pairs with the use of a reciprocating tribometer under lubricated conditions (artificial saliva). The normal force used in the tests was 20 N the time for each test was of 60 min. The stroke length was 2 mm, according to the range of displacement used in scientific literature. The wear mass loss evaluation was evaluated by using a gravimetric method. In order to characterize the wear mechanisms, present in the worn surfaces after each of tribo-tests, a topographic analysis was carried with a 3D non-contact optical profiler. The results show that the minimum value of the COF is obtained in the case of Zirconia vs. Zirconia tribo-couple. The results on the wear mass loss show a very low wear rate when coupling in tribological condition natural tooth with a ceramic restoration (a mean value of 0.5 mg was found). This rate is even lower when the contact is between two artificial zirconia teeth.


Assuntos
Fricção , Dente/química , Zircônio/química , Odontologia , Humanos , Teste de Materiais
17.
PLoS One ; 14(3): e0213173, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30893326

RESUMO

Proving voyaging at sea by Palaeolithic humans is a difficult archaeological task, even for short distances. In the Mediterranean, a commonly accepted sea crossing is that from the Italian Peninsula to Sicily by anatomically modern humans, purportedly of the Aurignacian culture. This claim, however, was only supported by the typological attribution to the Aurignacian of the lithic industries from the insular site of Fontana Nuova. AMS radiocarbon dating undertaken as part of our research shows that the faunal remains, previously considered Aurignacian, actually date to the Holocene. Absolute dating on dentinal collagen also attributes the human teeth from the site to the early Holocene, although we were unable to obtain ancient DNA to evaluate their ancestry. Ten radiocarbon dates on human and other taxa are comprised between 9910-9700 cal. BP and 8600-8480 cal. BP, indicating that Fontana Nuova was occupied by Mesolithic and not Aurignacian hunter-gatherers. Only a new study of the lithic assemblage could establish if the material from Fontana Nuova is a mixed collection that includes both late Upper Palaeolithic (Epigravettian) and Mesolithic artefacts, as can be suggested by taking into account both the results of our study and of the most recent reinterpretation of the lithics. Nevertheless, this research suggests that the notion that Aurignacian groups were present in Sicily should now be revised. Another outcome of our study is that we found that three specimens, attributed on grounds both of morphological and ZooMS identifications to Cervus elaphus, had δ13C values significantly higher than any available for such species in Europe.


Assuntos
Radioisótopos de Carbono/análise , Fósseis/história , Datação Radiométrica/métodos , Restos Mortais/química , História Antiga , Humanos , Itália , Dente/química
18.
Methods Mol Biol ; 1922: 239-250, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30838582

RESUMO

The organic material in developing dentin is 90% type I collagen and 10% non-collagenous proteins. The key to understanding dentin biomineralization is to study how these proteins collectively precipitate and organize hydroxyapatite crystals. The first step in characterizing the proteins within a mineralizing matrix is to efficiently extract and isolate the essential molecular participants and elucidate their structural and biochemical properties. In this study, we expanded previous approaches to develop an improved strategy for the extraction of extracellular matrix proteins from the dentin of developing teeth. Proteins in dentin powder were sequentially extracted in the order Tris-guanidine buffer, HCl-formic acid solution, acetic acid-NaCl solution, Tris-NaCl buffer, and a second Tris-guanidine buffer. Individual fractions were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), by gelatin or casein zymography, and by Western blot analysis using dentin sialoprotein (DSP)- or dentin glycoprotein (DGP)-specific antibodies. This approach was used to purify assorted porcine dentin non-collagenous proteins.


Assuntos
Western Blotting/métodos , Dentina/química , Eletroforese em Gel de Poliacrilamida/métodos , Proteínas da Matriz Extracelular/isolamento & purificação , Glicoproteínas/isolamento & purificação , Fosfoproteínas/isolamento & purificação , Sialoglicoproteínas/isolamento & purificação , Dente/química , Ácido Acético/química , Animais , Dentina/crescimento & desenvolvimento , Formiatos/química , Guanidina/química , Suínos , Dente/crescimento & desenvolvimento , Trometamina/química
19.
Nature ; 565(7741): 640-644, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30700871

RESUMO

Denisova Cave in the Siberian Altai (Russia) is a key site for understanding the complex relationships between hominin groups that inhabited Eurasia in the Middle and Late Pleistocene epoch. DNA sequenced from human remains found at this site has revealed the presence of a hitherto unknown hominin group, the Denisovans1,2, and high-coverage genomes from both Neanderthal and Denisovan fossils provide evidence for admixture between these two populations3. Determining the age of these fossils is important if we are to understand the nature of hominin interaction, and aspects of their cultural and subsistence adaptations. Here we present 50 radiocarbon determinations from the late Middle and Upper Palaeolithic layers of the site. We also report three direct dates for hominin fragments and obtain a mitochondrial DNA sequence for one of them. We apply a Bayesian age modelling approach that combines chronometric (radiocarbon, uranium series and optical ages), stratigraphic and genetic data to calculate probabilistically the age of the human fossils at the site. Our modelled estimate for the age of the oldest Denisovan fossil suggests that this group was present at the site as early as 195,000 years ago (at 95.4% probability). All Neanderthal fossils-as well as Denisova 11, the daughter of a Neanderthal and a Denisovan4-date to between 80,000 and 140,000 years ago. The youngest Denisovan dates to 52,000-76,000 years ago. Direct radiocarbon dating of Upper Palaeolithic tooth pendants and bone points yielded the earliest evidence for the production of these artefacts in northern Eurasia, between 43,000 and 49,000 calibrated years before present (taken as AD 1950). On the basis of current archaeological evidence, it may be assumed that these artefacts are associated with the Denisovan population. It is not currently possible to determine whether anatomically modern humans were involved in their production, as modern-human fossil and genetic evidence of such antiquity has not yet been identified in the Altai region.


Assuntos
Cavernas , Fósseis , Hominidae , Datação Radiométrica , Animais , Teorema de Bayes , DNA Mitocondrial/genética , Cervos , Fêmur/química , Sedimentos Geológicos/química , História Antiga , Hominidae/genética , Humanos , Homem de Neandertal/genética , Isótopos de Oxigênio , Sibéria , Fatores de Tempo , Dente/química
20.
Mater Sci Eng C Mater Biol Appl ; 97: 644-649, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30678951

RESUMO

The crystalline indexes obtained through infrared spectroscopy (CIIR) and X-ray diffraction (CIXRD) were used to analyze the structural changes of dentin and enamel in human teeth when subjected to heat treatments between room temperature (25 °C) to 1200 °C in atmospheric air and argon. Thermogravimetric (TGA) and differential scanning calorimetry (DSC) analyses of sound powders were also used to support the analysis. As the temperature increased, the CIXRD increased exhibiting a behavior like that of the crystal grain size, and the CIIR increased until the ß-TCP phase appeared. These results indicated that the CIIR was more variable to structural changes than the CIXRD.


Assuntos
Espectroscopia de Infravermelho com Transformada de Fourier , Dente/química , Difração de Raios X , Fosfatos de Cálcio/química , Varredura Diferencial de Calorimetria , Cristalização , Esmalte Dentário/química , Dentina/química , Humanos , Temperatura , Termogravimetria
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