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1.
Nature ; 618(7964): 328-332, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37138083

RESUMO

Artefacts made from stones, bones and teeth are fundamental to our understanding of human subsistence strategies, behaviour and culture in the Pleistocene. Although these resources are plentiful, it is impossible to associate artefacts to specific human individuals1 who can be morphologically or genetically characterized, unless they are found within burials, which are rare in this time period. Thus, our ability to discern the societal roles of Pleistocene individuals based on their biological sex or genetic ancestry is limited2-5. Here we report the development of a non-destructive method for the gradual release of DNA trapped in ancient bone and tooth artefacts. Application of the method to an Upper Palaeolithic deer tooth pendant from Denisova Cave, Russia, resulted in the recovery of ancient human and deer mitochondrial genomes, which allowed us to estimate the age of the pendant at approximately 19,000-25,000 years. Nuclear DNA analysis identifies the presumed maker or wearer of the pendant as a female individual with strong genetic affinities to a group of Ancient North Eurasian individuals who lived around the same time but were previously found only further east in Siberia. Our work redefines how cultural and genetic records can be linked in prehistoric archaeology.


Assuntos
Osso e Ossos , DNA Antigo , Dente , Animais , Feminino , Humanos , Arqueologia/métodos , Osso e Ossos/química , Cervos/genética , DNA Antigo/análise , DNA Antigo/isolamento & purificação , DNA Mitocondrial/análise , DNA Mitocondrial/isolamento & purificação , História Antiga , Sibéria , Dente/química , Cavernas , Federação Russa
2.
Nature ; 592(7853): 253-257, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33828320

RESUMO

Modern humans appeared in Europe by at least 45,000 years ago1-5, but the extent of their interactions with Neanderthals, who disappeared by about 40,000 years ago6, and their relationship to the broader expansion of modern humans outside Africa are poorly understood. Here we present genome-wide data from three individuals dated to between 45,930 and 42,580 years ago from Bacho Kiro Cave, Bulgaria1,2. They are the earliest Late Pleistocene modern humans known to have been recovered in Europe so far, and were found in association with an Initial Upper Palaeolithic artefact assemblage. Unlike two previously studied individuals of similar ages from Romania7 and Siberia8 who did not contribute detectably to later populations, these individuals are more closely related to present-day and ancient populations in East Asia and the Americas than to later west Eurasian populations. This indicates that they belonged to a modern human migration into Europe that was not previously known from the genetic record, and provides evidence that there was at least some continuity between the earliest modern humans in Europe and later people in Eurasia. Moreover, we find that all three individuals had Neanderthal ancestors a few generations back in their family history, confirming that the first European modern humans mixed with Neanderthals and suggesting that such mixing could have been common.


Assuntos
DNA Antigo/análise , Genoma Humano/genética , Homem de Neandertal/genética , Alelos , América/etnologia , Animais , Arqueologia , Bulgária/etnologia , Cavernas , Ásia Oriental/etnologia , Feminino , História Antiga , Humanos , Masculino , Filogenia
3.
Nature ; 581(7808): 299-302, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32433609

RESUMO

The Middle to Upper Palaeolithic transition in Europe witnessed the replacement and partial absorption of local Neanderthal populations by Homo sapiens populations of African origin1. However, this process probably varied across regions and its details remain largely unknown. In particular, the duration of chronological overlap between the two groups is much debated, as are the implications of this overlap for the nature of the biological and cultural interactions between Neanderthals and H. sapiens. Here we report the discovery and direct dating of human remains found in association with Initial Upper Palaeolithic artefacts2, from excavations at Bacho Kiro Cave (Bulgaria). Morphological analysis of a tooth and mitochondrial DNA from several hominin bone fragments, identified through proteomic screening, assign these finds to H. sapiens and link the expansion of Initial Upper Palaeolithic technologies with the spread of H. sapiens into the mid-latitudes of Eurasia before 45 thousand years ago3. The excavations yielded a wealth of bone artefacts, including pendants manufactured from cave bear teeth that are reminiscent of those later produced by the last Neanderthals of western Europe4-6. These finds are consistent with models based on the arrival of multiple waves of H. sapiens into Europe coming into contact with declining Neanderthal populations7,8.


Assuntos
Fósseis , Migração Humana/história , Animais , Ásia , Osso e Ossos/metabolismo , Bulgária , Cavernas , DNA Antigo/isolamento & purificação , DNA Mitocondrial/genética , DNA Mitocondrial/isolamento & purificação , Europa (Continente) , História Antiga , Humanos , Homem de Neandertal/genética , Filogenia , Comportamento de Utilização de Ferramentas , Dente/anatomia & histologia , Dente/metabolismo
4.
J Hum Evol ; 167: 103198, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35533625

RESUMO

The expansion of Homo sapiens and our interaction with local environments, including the replacement or absorption of local populations, is a key component in understanding the evolution of our species. Of special interest are artifacts made from hard animal tissues from layers at Bacho Kiro Cave (Bulgaria) that have been attributed to the Initial Upper Paleolithic. The Initial Upper Paleolithic is characterized by Levallois-like blade technologies that can co-occur with bone tools and ornaments and likely represents the dispersal of H. sapiens into several regions throughout Eurasia starting by 45 ka or possibly earlier. Osseous artifacts from the Initial Upper Paleolithic are important components of this record and have the potential to contribute to our understanding of group interactions and population movements. Here, we present a zooarchaeological, technological, and functional analysis of the diverse and sizable osseous artifact collection from Bacho Kiro Cave. Animal raw material sources are consistent with taxa found within the faunal assemblage including cervids, large bovids, and cave bears. A variety of bone tool morphologies, both formal and informal, indicate a diverse technological approach for conducting various on-site activities, many of which were focused on the processing of animal skins, likely for cold weather clothing. Technological flexibility is also evident in the manufacture of personal ornaments, which were made primarily from carnivore teeth, especially cave bear, though herbivore teeth and small beads are also represented. The osseous artifacts from Bacho Kiro Cave provide a series of insights into the bone technology and indirectly on the social aspects of these humans in southeast Europe, and when placed within the broader Initial Upper Paleolithic context, both regional and shared behaviors are evidently indicating widespread innovation and complexity. This is especially significant given the location and chronology of the site in the context of H. sapiens dispersals.


Assuntos
Arqueologia , Hominidae , Animais , Bulgária , Cavernas , Fósseis , Tecnologia
5.
J Hum Evol ; 161: 103074, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34628301

RESUMO

The behavioral dynamics underlying the expansion of Homo sapiens into Europe remains a crucial topic in human evolution. Owing to poor bone preservation, past studies have strongly focused on the Initial Upper Paleolithic (IUP) stone tool record. Recent excavations and extensive radiocarbon dating at Bacho Kiro Cave (Bulgaria) pushed back the arrival of IUP H. sapiens into Europe to ca. 45,000 years ago. This site has exceptional bone preservation, and we present the study of 7431 faunal remains from across two IUP layers (I and J) and one Middle Paleolithic layer (K). We identified a shift in site use and occupation intensity through time, marked by increased find density and human modifications in Layer I. Alongside a decrease in carnivore presence and seasonality data demonstrating human presence in all seasons, this indicates a more frequent or prolonged occupation of the site by IUP groups. Contrarily, the dietary focus across the IUP and Middle Paleolithic layers is similar, centered on the exploitation of species from a range of habitats including Bos/Bison, Cervidae, Equidae, and Caprinae. While body parts of large herbivores were selectively transported into the site, the bear remains suggest that these animals died in the cave itself. A distinct aspect of the IUP occupation is an increase in carnivore remains with human modifications, including these cave bears but also smaller taxa (e.g., Canis lupus, Vulpes vulpes). This can be correlated with their exploitation for pendants, and potentially for skins and furs. At a broader scale, we identified similarities in subsistence behavior across IUP sites in Europe and western Asia. It appears that the first IUP occupations were less intense with find densities and human modifications increasing in succeeding IUP layers. Moreover, the exploitation of small game appears to be limited across IUP sites, while carnivore exploitation seems a recurrent strategy.


Assuntos
Arqueologia , Hominidae , Animais , Bulgária , Cavernas , Europa (Continente) , Fósseis
6.
J Hum Evol ; 111: 54-62, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28874274

RESUMO

Excavations conducted by a Bulgarian-French team at Kozarnika Cave (Balkans, Bulgaria) during several seasons yielded a long Paleolithic archaeological sequence and led to the discovery of important faunal, lithic, and human samples. This paper aims to describe the unpublished radius shaft of an infant who died approximately before the sixth month postnatal that was recovered from layer 10b, which contained East Balkan Levallois Mousterian with bifacial leaf points. The layer was dated between 130 and 200 ka (large mammals biochronology) and between 128 ± 13 ka and 183 ± 14 ka (OSL), i.e. OIS6. Here we show that, given the scarcity of Middle Pleistocene infant remains in general, and Middle Paleolithic human remains from this part of Eastern Europe in particular, the study of the Kozarnika specimen is of special interest. We discuss its place in the Middle Pleistocene European hominine record and substantiate the hypothesis of early Neanderthal presence in the eastern Balkans.


Assuntos
Fósseis/anatomia & histologia , Homem de Neandertal , Rádio (Anatomia)/anatomia & histologia , Animais , Península Balcânica , Bulgária , Cavernas , Humanos , Lactente
7.
Proc Natl Acad Sci U S A ; 109(34): 13532-7, 2012 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-22826222

RESUMO

Marked changes in human dispersal and development during the Middle to Upper Paleolithic transition have been attributed to massive volcanic eruption and/or severe climatic deterioration. We test this concept using records of volcanic ash layers of the Campanian Ignimbrite eruption dated to ca. 40,000 y ago (40 ka B.P.). The distribution of the Campanian Ignimbrite has been enhanced by the discovery of cryptotephra deposits (volcanic ash layers that are not visible to the naked eye) in archaeological cave sequences. They enable us to synchronize archaeological and paleoclimatic records through the period of transition from Neanderthal to the earliest anatomically modern human populations in Europe. Our results confirm that the combined effects of a major volcanic eruption and severe climatic cooling failed to have lasting impacts on Neanderthals or early modern humans in Europe. We infer that modern humans proved a greater competitive threat to indigenous populations than natural disasters.


Assuntos
Fósseis , Homem de Neandertal , Erupções Vulcânicas , Animais , Arqueologia/métodos , Clima , Hominidae , Humanos , Espectrometria de Massas/métodos , Microscopia Eletrônica de Varredura/métodos
8.
World J Radiol ; 15(5): 136-145, 2023 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-37275303

RESUMO

Prostate cancer (Pca; adenocarcinoma) is one of the most common cancers in adult males and one of the leading causes of death in both men and women. The diagnosis of Pca requires substantial experience, and even then the lesions can be difficult to detect. Moreover, although the diagnostic approach for this disease has improved significantly with the advent of multiparametric magnetic resonance, that technology has certain unresolved limitations. In recent years artificial intelligence (AI) has been introduced to the field of radiology, providing new software solutions for prostate diagnostics. Precise mapping of the prostate has become possible through AI and this has greatly improved the accuracy of biopsy. AI has also allowed for certain suspicious lesions to be attributed to a given group according to the Prostate Imaging-Reporting & Data System classification. Finally, AI has facilitated the combination of data obtained from clinical, laboratory (prostate-specific antigen), imaging (magnetic resonance), and biopsy examinations, and in this way new regularities can be found which at the moment remain hidden. Further evolution of AI in this field is inevitable and it is almost certain to significantly expand the efficacy, accuracy and efficiency of diagnosis and treatment of Pca.

9.
Life (Basel) ; 13(9)2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37763309

RESUMO

(1) Although new imaging methods for examining the GIT with high diagnostic capabilities were introduced, the improvement and implementation of safe, efficient, and cost-effective approaches continue, and GIT diseases are still challenging to diagnose; (2) Methods: We aim to show the possibilities of computed tomography (CT) colonography for early diagnosis of colon diseases using a multidetector 32-channel CT scanner after appropriate preparation; (3) Results: After a colonoscopy was performed earlier, 140 patients were examined with CT colonography. Complete colonoscopy was performed in 80 patients (57.1%) out of 140 who underwent CT colonography. Incomplete colonoscopy was observed in 52 patients (37.2%); in 5 patients (3.6%), it was contraindicated, and in 3 patients (2.1%), it was not performed because of patients' refusal. We determined that in cases of complete FCS in 95% of patients, CT colonography established the same clinical diagnosis as FCS. In cases of incomplete, refused, or contraindicated FCS in 32.7% (17 patients), FCS failed to diagnose correctly. The main reasons for incomplete colonoscopy were: intraluminal obturation of tumor nature-17 patients (33%), extraluminal obturation (compression) from a tumor formation-4 patients (8%), stenotic changes of non-tumor nature-11 patients (21%), congenital diseases with changes in the length of the lumen of the intestinal loops-7 patients (13%), and subjective factors (pain, poor preparation, contraindications) in 13 patients (25%); (4) Conclusions: Our results confirmed that CT colonography is a method of choice in cases of negative FCS results accompanied by clinical data for the neoplastic process and in cases of incomplete and contraindicated FCS. Also, the insufflation system we developed optimizes the method by improving the quality of the obtained images and ensuring good patient tolerance.

10.
Sci Adv ; 7(39): eabi4642, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34550733

RESUMO

The expansion of Homo sapiens across Eurasia marked a major milestone in human evolution that would eventually lead to our species being found across every continent. Current models propose that these expansions occurred only during episodes of warm climate, based on age correlations between archaeological and climatic records. Here, we obtain direct evidence for the temperatures faced by some of these humans through the oxygen isotope analysis of faunal remains from Bacho Kiro Cave, Bulgaria, the earliest clear record of H. sapiens in Europe. The results indicate that humans ∼45,000 years ago experienced subarctic climates with far colder climatic conditions than previously suggested. This demonstrates that the early presence of H. sapiens in Europe was not contingent on warm climates. Our results necessitate the revision of key models of human expansion and highlight the need for a less deterministic role of climate in the study of our evolutionary history.

11.
Sci Rep ; 11(1): 23611, 2021 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-34880290

RESUMO

Bone surface modifications are crucial for understanding human subsistence and dietary behaviour, and can inform about the techniques employed in the production and use of bone tools. Permission to destructively sample such unique artefacts is not always granted. The recent development of non-destructive proteomic extraction techniques has provided some alternatives for the analysis of rare and culturally significant artefacts, including bone tools and personal ornaments. The Eraser Extraction Method (EEM), first developed for ZooMS analysis of parchment, has recently been applied to bone and ivory specimens. To test the potential impact of the EEM on ancient bone surfaces, we analyse six anthropogenically modified Palaeolithic bone specimens from Bacho Kiro Cave (Bulgaria) through a controlled sampling experiment using qualitative and 3D quantitative microscopy. Although the overall bone topography is generally preserved, our findings demonstrate a slight flattening of the microtopography alongside the formation of micro-striations associated with the use of the eraser for all bone specimens. Such modifications are similar to ancient use-wear traces. We therefore consider the EEM a destructive sampling approach for Palaeolithic bone surfaces. Together with low ZooMS success rates in some of the reported studies, the EEM might not be a suitable approach to taxonomically identify Pleistocene bone specimens.


Assuntos
Osso e Ossos/metabolismo , Fósseis , Proteômica/métodos , Arqueologia , Bulgária , Humanos , Propriedades de Superfície
12.
BMC Bioinformatics ; 11 Suppl 6: S23, 2010 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-20946607

RESUMO

BACKGROUND: Dermoscopy is one of the major imaging modalities used in the diagnosis of melanoma and other pigmented skin lesions. Automated assessment tools for dermoscopy images have become an important field of research mainly because of inter- and intra-observer variations in human interpretation. One of the most important steps in dermoscopy image analysis is the detection of lesion borders, since many other features, such as asymmetry, border irregularity, and abrupt border cutoff, rely on the boundary of the lesion. RESULTS: To automate the process of delineating the lesions, we employed Active Contour Model (ACM) and boundary-driven density-based clustering (BD-DBSCAN) algorithms on 50 dermoscopy images, which also have ground truths to be used for quantitative comparison. We have observed that ACM and BD-DBSCAN have the same border error of 6.6% on all images. To address noisy images, BD-DBSCAN can perform better delineation than ACM. However, when used with optimum parameters, ACM outperforms BD-DBSCAN, since ACM has a higher recall ratio. CONCLUSION: We successfully proposed two new frameworks to delineate suspicious lesions with i) an ACM integrated approach with sharpening and ii) a fast boundary-driven density-based clustering technique. ACM shrinks a curve toward the boundary of the lesion. To guide the evolution, the model employs the exact solution 27 of a specific form of the Geometric Heat Partial Differential Equation 28. To make ACM advance through noisy images, an improvement of the model's boundary condition is under consideration. BD-DBSCAN improves regular density-based algorithm to select query points intelligently.


Assuntos
Dermoscopia/instrumentação , Interpretação de Imagem Assistida por Computador/métodos , Melanoma/diagnóstico , Neoplasias Cutâneas/diagnóstico , Dermoscopia/métodos , Humanos , Aumento da Imagem/métodos , Melanoma/patologia , Reconhecimento Automatizado de Padrão/métodos , Neoplasias Cutâneas/patologia
13.
Nat Ecol Evol ; 4(6): 794-801, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32393865

RESUMO

The stratigraphy at Bacho Kiro Cave, Bulgaria, spans the Middle to Upper Palaeolithic transition, including an Initial Upper Palaeolithic (IUP) assemblage argued to represent the earliest arrival of Upper Palaeolithic Homo sapiens in Europe. We applied the latest techniques in 14C dating to an extensive dataset of newly excavated animal and human bones to produce a robust, high-precision radiocarbon chronology for the site. At the base of the stratigraphy, the Middle Palaeolithic (MP) occupation dates to >51,000 yr BP. A chronological gap of over 3,000 years separates the MP occupation from the occupation of the cave by H. sapiens, which extends to 34,000 cal BP. The extensive IUP assemblage, now associated with directly dated H. sapiens fossils at this site, securely dates to 45,820-43,650 cal BP (95.4% probability), probably beginning from 46,940 cal BP (95.4% probability). The results provide chronological context for the early occupation of Europe by Upper Palaeolithic H. sapiens.


Assuntos
Cavernas , Datação Radiométrica , Animais , Bulgária , Europa (Continente) , Fósseis , Humanos
14.
Folia Med (Plovdiv) ; 48(1): 46-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16918054

RESUMO

OBJECTIVE: Our aim was to develop an insufflation system for CT colonography enabling even and quick air inflation as well as pressure control and optional emergency decompression. PATIENTS AND METHODS: A modified air insufflation system for CT colonography, consisting of an electric air pump, manometer, safety valve, and a balloon tip is presented. Thirty one patients underwent CT colonography from August to December, 2004. RESULTS: Optimal distension was achieved in 30 patients; the distension was incomplete (partial) only in one case. The insufflation was performed within 60 seconds in 28 of the cases, in 2 patients--within 180 seconds and in one patient--after 180 seconds. CONCLUSIONS: The presented insufflation system allows optimization of CT colonography technique, reduces the risk of adverse events during examination and improves the precision of the method.


Assuntos
Ar , Doenças do Colo/diagnóstico por imagem , Colonografia Tomográfica Computadorizada/métodos , Insuflação/métodos , Colonografia Tomográfica Computadorizada/instrumentação , Humanos , Insuflação/instrumentação
15.
Comput Med Imaging Graph ; 36(7): 572-9, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22819294

RESUMO

Dermoscopy, also known as epiluminescence microscopy, is a major imaging technique used in the assessment of melanoma and other diseases of skin. In this study we propose a computer aided method and tools for fast and automated diagnosis of malignant skin lesions using non-linear classifiers. The method consists of three main stages: (1) skin lesion features extraction from images; (2) features measurement and digitization; and (3) skin lesion binary diagnosis (classification), using the extracted features. A shrinking active contour (S-ACES) extracts color regions boundaries, the number of colors, and lesion's boundary, which is used to calculate the abrupt boundary. Quantification methods for measurements of asymmetry and abrupt endings in skin lesions are elaborated to approach the second stage of the method. The total dermoscopy score (TDS) formula of the ABCD rule is modeled as linear support vector machines (SVM). Further a polynomial SVM classifier is developed. To validate the proposed framework a dataset of 64 lesion images were selected from a collection with a ground truth. The lesions were classified as benign or malignant by the TDS based model and the SVM polynomial classifier. Comparing the results, we showed that the latter model has a better f-measure then the TDS-based model (linear classifier) in the classification of skin lesions into two groups, malignant and benign.


Assuntos
Dermoscopia/métodos , Tomografia Computadorizada Quadridimensional , Interpretação de Imagem Assistida por Computador/métodos , Melanoma/diagnóstico , Neoplasias Cutâneas/diagnóstico , Humanos , Melanoma/classificação , Neoplasias Cutâneas/classificação
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