Dairying enabled Early Bronze Age Yamnaya steppe expansions.

During the Early Bronze Age, populations of the western Eurasian steppe expanded across an immense area of northern Eurasia. Combined archaeological and genetic evidence supports widespread Early Bronze Age population movements out of the Pontic-Caspian steppe that resulted in gene flow across vast distances, linking populations of Yamnaya pastoralists in Scandinavia with pastoral populations (known as the Afanasievo) far to the east in the Altai Mountains1,2 and Mongolia3. Although some models hold that this expansion was the outcome of a newly mobile pastoral economy characterized by horse traction, bulk wagon transport4-6 and regular dietary dependence on meat and milk5, hard evidence for these economic features has not been found. Here we draw on proteomic analysis of dental calculus from individuals from the western Eurasian steppe to demonstrate a major transition in dairying at the start of the Bronze Age. The rapid onset of ubiquitous dairying at a point in time when steppe populations are known to have begun dispersing offers critical insight into a key catalyst of steppe mobility. The identification of horse milk proteins also indicates horse domestication by the Early Bronze Age, which provides support for its role in steppe dispersals. Our results point to a potential epicentre for horse domestication in the Pontic-Caspian steppe by the third millennium BC, and offer strong support for the notion that the novel exploitation of secondary animal products was a key driver of the expansions of Eurasian steppe pastoralists by the Early Bronze Age.

The genomic origins of the Bronze Age Tarim Basin mummies.

The identity of the earliest inhabitants of Xinjiang, in the heart of Inner Asia, and the languages that they spoke have long been debated and remain contentious1. Here we present genomic data from 5 individuals dating to around 3000-2800 BC from the Dzungarian Basin and 13 individuals dating to around 2100-1700 BC from the Tarim Basin, representing the earliest yet discovered human remains from North and South Xinjiang, respectively. We find that the Early Bronze Age Dzungarian individuals exhibit a predominantly Afanasievo ancestry with an additional local contribution, and the Early-Middle Bronze Age Tarim individuals contain only a local ancestry. The Tarim individuals from the site of Xiaohe further exhibit strong evidence of milk proteins in their dental calculus, indicating a reliance on dairy pastoralism at the site since its founding. Our results do not support previous hypotheses for the origin of the Tarim mummies, who were argued to be Proto-Tocharian-speaking pastoralists descended from the Afanasievo1,2 or to have originated among the Bactria-Margiana Archaeological Complex3 or Inner Asian Mountain Corridor cultures4. Instead, although Tocharian may have been plausibly introduced to the Dzungarian Basin by Afanasievo migrants during the Early Bronze Age, we find that the earliest Tarim Basin cultures appear to have arisen from a genetically isolated local population that adopted neighbouring pastoralist and agriculturalist practices, which allowed them to settle and thrive along the shifting riverine oases of the Taklamakan Desert.

Tracking the transition to agriculture in Southern Europe through ancient DNA analysis of dental calculus.

Archaeological dental calculus, or mineralized plaque, is a key tool to track the evolution of oral microbiota across time in response to processes that impacted our culture and biology, such as the rise of farming during the Neolithic. However, the extent to which the human oral flora changed from prehistory until present has remained elusive due to the scarcity of data on the microbiomes of prehistoric humans. Here, we present our reconstruction of oral microbiomes via shotgun metagenomics of dental calculus in 44 ancient foragers and farmers from two regions playing a pivotal role in the spread of farming across Europe-the Balkans and the Italian Peninsula. We show that the introduction of farming in Southern Europe did not alter significantly the oral microbiomes of local forager groups, and it was in particular associated with a higher abundance of the species Olsenella sp. oral taxon 807. The human oral environment in prehistory was dominated by a microbial species, Anaerolineaceae bacterium oral taxon 439, that diversified geographically. A Near Eastern lineage of this bacterial commensal dispersed with Neolithic farmers and replaced the variant present in the local foragers. Our findings also illustrate that major taxonomic shifts in human oral microbiome composition occurred after the Neolithic and that the functional profile of modern humans evolved in recent times to develop peculiar mechanisms of antibiotic resistance that were previously absent.

Exotic foods reveal contact between South Asia and the Near East during the second millennium BCE.

Although the key role of long-distance trade in the transformation of cuisines worldwide has been well-documented since at least the Roman era, the prehistory of the Eurasian food trade is less visible. In order to shed light on the transformation of Eastern Mediterranean cuisines during the Bronze Age and Early Iron Age, we analyzed microremains and proteins preserved in the dental calculus of individuals who lived during the second millennium BCE in the Southern Levant. Our results provide clear evidence for the consumption of expected staple foods, such as cereals (Triticeae), sesame (Sesamum), and dates (Phoenix). We additionally report evidence for the consumption of soybean (Glycine), probable banana (Musa), and turmeric (Curcuma), which pushes back the earliest evidence of these foods in the Mediterranean by centuries (turmeric) or even millennia (soybean). We find that, from the early second millennium onwards, at least some people in the Eastern Mediterranean had access to food from distant locations, including South Asia, and such goods were likely consumed as oils, dried fruits, and spices. These insights force us to rethink the complexity and intensity of Indo-Mediterranean trade during the Bronze Age as well as the degree of globalization in early Eastern Mediterranean cuisine.

A proof of principle investigation of a novel enzyme formulation on dental calculus deposition: a 4-week randomized human clinical trial.

BACKGROUND: The dissolution of dental calculus, safely and at home, is among the more challenging issues facing the over-the-counter healthcare industry. Pontis Biologics, Inc. has developed novel model of calculus development and structure and has formulated a dentifrice (Tartarase™) using digestive enzymes as active ingredients that is shown to dissolve dental calculus in this Proof of Principle clinical trial. METHODS: This investigation was designed to evaluate the safety and efficacy of a novel enzyme formulation to remove existing calculus deposits in 4 weeks, measured using the Volpe-Manhold Index (V-MI) on lingual surfaces of 6 lower anterior teeth. The test formulation was compared to Crest Cavity Protection, as a control dentifrice. A total of 40 randomized test subjects began the study with 20 assigned to the control dentifrice and 20 assigned to the Tartarase groups (ten each, one brushing with Tartarase twice daily and one brushed with Tartarase and wore a dental tray filled with Tartarase for 30 min then brushed again with Tartarase, once daily). RESULTS: The Crest group experienced a 12% increase in calculus, in contrast to the results of both Tartarase groups that experienced a 40% reduction in calculus in 4 weeks of unsupervised at home use of the Tartarase toothpaste formulation. CONCLUSIONS: This proof of principle study demonstrates that a dentifrice, formulated along the lines of the Tartarase material, is capable of combating calculus accumulation using the same oral hygiene habits that are common worldwide. TRIAL REGISTRATION: This trial was registered retrospectively at clinicaltrials.gov and has the Unique Identification Number: NCT06139835, 14/11/2023.

Prevalence of rapid calculus formers and its associated factors amongst patients visiting a dental hospital: a preliminary investigation.

BACKGROUND: This study focuses on the determination and classification of patients as rapid or slowcalculusformersbasedontherateofcalculusformationafteroralprophylaxis. It also aims to determine the factors that positively impact the formation and deposition of calculus in patients and identify the factors that accelerate or decelerate the deposition of calculus. METHODS: The study was conducted in the Department of Periodontology, Dr Harvansh Singh Judge Institute of Dental Sciences and Hospital, Panjab University Chandigarh, India. We examined 51 patients after a month of the oral prophylaxis, recorded the amount of calculus present in the oral cavity, and then recorded a detailed history which was briefly divided into Age, Sex, Residence, Oral habits, and maintenance of oral hygiene. RESULTS: An evident and meaningful link was found between age and the rate at which dental calculus forms. The average age of individuals differed significantly between the rapid and slow calculus formers, which could be ascribed to the decline in manual dexterity as age increases, resulting in less effective oral hygiene habits, including toothbrushing. None of the other factors dietary and oral hygiene related could be identified distinctly, probably owing to the small sample of the study. The oral health status exhibited a significant difference between slow and rapid calculus formers. CONCLUSIONS: Within the limitations of the study, the data analyzed, identified age as a significant determinant that impact the rate of formation of calculus in patients and reported a significant difference in the oral health status of rapid and slow calculus formers.

Ecology, Not Host Phylogeny, Shapes the Oral Microbiome in Closely Related Species.

Host-associated microbiomes are essential for a multitude of biological processes. Placed at the contact zone between external and internal environments, the little-studied oral microbiome has important roles in host physiology and health. Here, we investigate the roles of host evolutionary relationships and ecology in shaping the oral microbiome in three closely related gorilla subspecies (mountain, Grauer's, and western lowland gorillas) using shotgun metagenomics of 46 museum-preserved dental calculus samples. We find that the oral microbiomes of mountain gorillas are functionally and taxonomically distinct from the other two subspecies, despite close evolutionary relationships and geographic proximity with Grauer's gorillas. Grauer's gorillas show intermediate bacterial taxonomic and functional, and dietary profiles. Altitudinal differences in gorilla subspecies ranges appear to explain these patterns, suggesting a close connection between dental calculus microbiomes and the environment, likely mediated through diet. This is further supported by the presence of gorilla subspecies-specific phyllosphere/rhizosphere taxa in the oral microbiome. Mountain gorillas show a high abundance of nitrate-reducing oral taxa, which may promote adaptation to a high-altitude lifestyle by modulating blood pressure. Our results suggest that ecology, rather than evolutionary relationships and geographic distribution, shape the oral microbiome in these closely related species.

Trends in deamidation across archaeological bones, ceramics and dental calculus.

The accumulation of post-translational modifications (PTMs) in proteins throughout the lifecycle has been studied for decades, particularly more so with the advent of soft-ionization mass spectrometry-based proteomic techniques. However, particular PTMs, such as the deamidations of asparagine and glutamine residues, continue to accumulate in proteins that remain into the forensic, archaeological, and palaeontological records. The accurate measurement of these ancient 'molecular timers' has been proposed as a method to not only differentiate between exogenous and endogenous proteins within complex mixtures (i.e., contamination), but also as a method of providing relative age estimations into geological time. In this study we explored the extent to which deamidation varies with chronological age across different proteins in bones, as well as investigated differences between proteins across dental calculus and archaeological ceramics. We also analysed the relationships between the observed extent of deamidation and the protein primary structure. We found that collagen obtained from archaeological bones showed a chronological dependence on the extent of deamidation observed, but only when they were from similar environments, supporting prior suggestions about 'thermal age' being a major influence on the deamidation observed. Our study on non-collagenous proteins (NCPs) in archaeological bones showed that while biglycan, and to a lesser extent chondroadherin, showed positive correlations between geological age and the extent of deamidation, others including fetuin-A and serum albumin did not. However, despite the well-known dependence of deamidation on the three-dimensional structure of the peptides, we were unable to find any clear correlation between the structural motifs of the peptides in archaeological bones and the extent of deamidation observed. Our analysis of a set of food proteins obtained from Neolithic archaeological ceramics in Çatalhöyük also showed similar deamidation levels irrespective of the protein structure. Overall, our results suggest that deamidation in archaeological samples could be useful for obtaining additional information beyond identification of species and tissue type, be that as a measure of protein endogeneity and potential contamination, or a measure of protein degradation, or as an indicator of thermal age and for relative dating; however, further research needs to be undertaken to understand why particular proteins are better for this than others, going beyond simple consideration of their secondary structure.

Neanderthal behaviour, diet, and disease inferred from ancient DNA in dental calculus.

Recent genomic data have revealed multiple interactions between Neanderthals and modern humans, but there is currently little genetic evidence regarding Neanderthal behaviour, diet, or disease. Here we describe the shotgun-sequencing of ancient DNA from five specimens of Neanderthal calcified dental plaque (calculus) and the characterization of regional differences in Neanderthal ecology. At Spy cave, Belgium, Neanderthal diet was heavily meat based and included woolly rhinoceros and wild sheep (mouflon), characteristic of a steppe environment. In contrast, no meat was detected in the diet of Neanderthals from El Sidrón cave, Spain, and dietary components of mushrooms, pine nuts, and moss reflected forest gathering. Differences in diet were also linked to an overall shift in the oral bacterial community (microbiota) and suggested that meat consumption contributed to substantial variation within Neanderthal microbiota. Evidence for self-medication was detected in an El Sidrón Neanderthal with a dental abscess and a chronic gastrointestinal pathogen (Enterocytozoon bieneusi). Metagenomic data from this individual also contained a nearly complete genome of the archaeal commensal Methanobrevibacter oralis (10.2× depth of coverage)-the oldest draft microbial genome generated to date, at around 48,000 years old. DNA preserved within dental calculus represents a notable source of information about the behaviour and health of ancient hominin specimens, as well as a unique system that is useful for the study of long-term microbial evolution.

Effect of phosphoproteins on intracellular calcification of bacteria.

This study aimed to evaluate the effects of phosphoproteins on bacterial mineralization. Dental calculus formation is attributed to bacterial mineralization in the oral cavity; however, the influence of phosphoproteins (which are abundant in saliva) is not clear. The model bacterium Escherichia coli was suspended in a calcification solution containing casein as a model phosphoprotein. To evaluate mineralization independent of bacterial metabolism, bacteria killed by heat treatment at 70°C were compared with viable bacteria. After incubation at 37°C for 24 h, the mode of calcification was observed using electron microscopy and energy dispersive x-ray spectroscopy. Solutions without casein produced precipitation in solution, which was identical to that in experiments without bacteria. In contrast, calcification solutions with 200 ppm casein only produced calcium phosphate deposition intracellularly. Without heat treatment, intracellular calcification rarely occurred, even when casein was added. Thus, phosphoproteins promoted intracellular calcification of dead bacteria; this is similar to the calcification of insoluble matrices, such as collagen fibrils, promoted by acidic polymers. We concluded that intracellular calcification is caused by the collagen fibril-like behavior of dead bacteria. The promotion of intracellular calcification of dead bacteria by phosphoproteins suggested a basic principle of dental calculus formation.

Oral health status of students with visual or hearing impairments in Northeast China.

BACKGROUND: Visual or hearing impairments in students seriously affect their quality of life. The aim of this study was to identify oral hygiene status and its influencing factors on visual or hearing impairments in students in Northeast China. METHODS: This study was conducted in May 2022. A total of 118 visually impaired students and 56 hearing impaired students from Northeast China were included in this study via census. Oral examinations and questionnaire-based surveys of students and their teachers were conducted. The oral examinations included caries experience, prevalence of gingival bleeding and dental calculus. The questionnaires included three parts: Social demographics (residence, sex and race) and parents' educational level; Oral hygiene habits and medical treatment behaviors; Knowledge and attitudes towards oral health care. This questionnaire was selected from the Fourth China National Oral Health Survey and the reliability and validity of the questionnaire were previously tested. T tests, one-way ANOVA, χ2 tests and multivariate logistic analyses were conducted to evaluate the differences and dependent variables of dental caries. RESULTS: The prevalence of dental caries in visually impaired and hearing impaired students were 66.10% and 66.07%. The mean number of DMFT, prevalence of gingival bleeding and dental calculus in visually impaired students were 2.71 ± 3.06, 52.08% and 59.38%, respectively. The mean number of DMFT, prevalence of gingival bleeding and dental calculus in hearing impaired students were 2.57 ± 2.83, 17.86% and 42.86%, respectively. The results of the multivariate logistic analysis showed that fluoride use and parents' educational background had an impact on the caries experience of visually impaired students. The daily toothbrushing frequency and parents' educational background had an impact on the caries experience of hearing impaired students. CONCLUSIONS: The oral health situation of students with visual or hearing impairments remains severe. It is still necessary to promote oral and general health in this population.

Isotope analysis of human dental calculus δ13 CO3 2- : Investigating a potential new proxy for sugar consumption.

RATIONALE: Dental calculus (mineralised dental plaque) is composed primarily of hydroxyapatite. We hypothesise that the carbonate component of dental calculus will reflect the isotopic composition of ingested simple carbohydrates. Therefore, dental calculus carbonates may be an indicator for sugar consumption, and an alternative to bone carbonate in isotopic palaeodiet studies. METHODS: We utilised Fourier transform infrared attenuated total reflectance analysis to characterise the composition and crystallisation of bone and dental calculus before isotope analysis of carbonate. Using a Sercon 20-22 mass spectrometer coupled with a Sercon GSL sample preparation system and an IsoPrime 100 dual inlet mass spectrometer plus Multiprep device to measure carbon, we tested the potential of dental calculus carbonate to identify C4 resources in diet through analysis of δ13 C values in paired bone, calculus and teeth mineral samples. RESULTS: The modern population shows higher δ13 C values in all three tissue carbonates compared to both archaeological populations. Clear differences in dental calculus δ13 C values are observed between the modern and archaeological individuals suggesting potential for utilising dental calculus in isotope palaeodiet studies. The offset between dental calculus and either bone or enamel carbonate δ13 C values is large and consistent in direction, with no consistent offset between the δ13 C values for the three tissues per individual. CONCLUSIONS: Our results support dental calculus carbonate as a new biomaterial to identify C4 sugar through isotope analysis. Greater carbon fractionation in the mouth is likely due to the complex formation of dental calculus as a mineralized biofilm, which results in consistently high δ13 C values compared to bone and enamel.

Relief food subsistence revealed by microparticle and proteomic analyses of dental calculus from victims of the Great Irish Famine.

Food and diet were class markers in 19th-century Ireland, which became evident as nearly 1 million people, primarily the poor and destitute, died as a consequence of the notorious Great Famine of 1845 to 1852. Famine took hold after a blight (Phytophthora infestans) destroyed virtually the only means of subsistence-the potato crop-for a significant proportion of the population. This study seeks to elucidate the variability of diet in mid-19th-century Ireland through microparticle and proteomic analysis of human dental calculus samples (n = 42) from victims of the famine. The samples derive from remains of people who died between August 1847 and March 1851 while receiving poor relief as inmates in the union workhouse in the city of Kilkenny (52°39' N, -7°15' W). The results corroborate the historical accounts of food provisions before and during the famine, with evidence of corn (maize), potato, and cereal starch granules from the microparticle analysis and milk protein from the proteomic analysis. Unexpectedly, there is also evidence of egg protein-a food source generally reserved only for export and the better-off social classes-which highlights the variability of the prefamine experience for those who died. Through historical contextualization, this study shows how the notoriously monotonous potato diet of the poor was opportunistically supplemented by other foodstuffs. While the Great Irish Famine was one of the worst subsistence crises in history, it was foremost a social disaster induced by the lack of access to food and not the lack of food availability.

The Hidden Secrets of the Dental Calculus: Calibration of a Mass Spectrometry Protocol for Dental Calculus Protein Analysis.

Dental calculus is a solid deposit that forms and accumulates on the tooth surface, entrapping oral microorganisms, biomolecules, and other micro-debris found in the oral cavity. A mass spectrometry analysis of its protein content opens a vista into the subject's diet, oral flora, and even some aspects of health, thus providing new insight and expanding our knowledge of archaic cultures. Multiple experimental protocols have been proposed for the optimal extraction of proteins from dental calculus. Herein, we compared various experimental conditions in order to calibrate and validate a protocol for protein extraction. Our results show that a high concentration of acetic acid followed by mechanical crushing and sonication provided the highest protein yield, while acetone precipitation enabled the identification of more distinct proteins. We validated this protocol using archeological samples, identifying human and microbial proteins in specimens from the eighth and seventeenth centuries (approximately 250-1300 years ago). These findings demonstrate that the developed protocol is useful for studying excavated archaeological samples and that it might be utilized to explore the biohistory, dietary habits, and microbiome of archaic populations.

The prevalence of gingivitis and related risk factors in schoolchildren aged 6-12 years old.

BACKGROUND: According to epidemiological studies, gingivitis is a common disease. However, its morbidity, considerably varies among individual. This study aimed to investigate the epidemiological characteristics of gingivitis, including prevalence, severity, intraoral distribution, and associated risk factors, in children aged 6-12 years in Jinzhou, China. METHODS: A multistage, whole-group, randomized sample of 2880 children aged 6-12 years in Jinzhou City, China, was selected and clinically examined. Each selected child completed a questionnaire on sociodemographic factors and oral health behaviors in cooperation with the investigator and teacher. Gingival bleeding refers to the bleeding of 10% or more teeth under the condition of ingivitis. Gingivitis was further categorized into localized gingivitis (30% ≥ number of teeth positive for gingival bleeding ≥ 10%) and generalized gingivitis (number of positive for gingival bleeding > 30%). The score of gingival bleeding was recorded using the Gingival Index. RESULTS: The prevalence of gingivitis in children aged 6-12 years in Jinzhou was 28.58%, including 701 cases of localized gingivitis (24.3%) and 122 cases of generalized gingivitis (4.2%). There were 429 cases (28.3%) of gingivitis in males and 394 cases (28.9%) in females, with no statistically significant difference in prevalence between males and females (P > 0.05). Chi-square tests and binary logistic regression analysis showed that aging, dental calculus, plaque, and dental crowding were significantly associated with a high prevalence of gingivitis. CONCLUSIONS: Our study showed that dental calculus, large amount dental plaque, poor oral health behavior, and oral health awareness are associated with the prevalence of gingivitis and maintaining children's oral health requires professional guidance and regular preventive care.

Comparing the Use of Magnetic Beads with Ultrafiltration for Ancient Dental Calculus Proteomics.

Over the past two decades, proteomic analysis has greatly developed in application to the field of biomolecular archaeology, coinciding with advancements in LC-MS/MS instrumentation sensitivity and improvements in sample preparation methods. Recently, human dental calculus has received much attention for its well-preserved proteomes locked in mineralized dental plaque which stores information on human diets and the oral microbiome otherwise invisible to other biomolecular approaches. Maximizing proteome recovery in ancient dental calculus, available only in minute quantities and irreplaceable after destructive analysis, is of paramount importance. Here, we compare the more traditional ultrafiltration-based and acetone precipitation approaches with the newer paramagnetic bead approach in order to test the influence of demineralization acid on recovered proteome complexity obtained from specimens as well as the sequence coverages matched for significant proteins. We found that a protocol utilizing EDTA combined with paramagnetic beads increased proteome complexity, in some cases doubling the number of unique peptides and number of proteins matched, compared to protocols involving the use of HCl and either acetone precipitation or ultrafiltration. Although the increase in the number of proteins was almost exclusively of bacterial origin, a development that has implications for the study of diseases within these ancient populations, an increase in the peptide number for the dairy proteins ß-lactoglobulin and casein was also observed reflecting an increase in sequence coverage for these dietary proteins of interest. We also consider structural explanations for the discrepancies observed between these two key dietary proteins preserved in archaeological dental calculus.

Dental Calculus as a Tool to Study the Evolution of the Mammalian Oral Microbiome.

Dental calculus, the calcified form of the mammalian oral microbial plaque biofilm, is a rich source of oral microbiome, host, and dietary biomolecules and is well preserved in museum and archaeological specimens. Despite its wide presence in mammals, to date, dental calculus has primarily been used to study primate microbiome evolution. We establish dental calculus as a valuable tool for the study of nonhuman host microbiome evolution, by using shotgun metagenomics to characterize the taxonomic and functional composition of the oral microbiome in species as diverse as gorillas, bears, and reindeer. We detect oral pathogens in individuals with evidence of oral disease, assemble near-complete bacterial genomes from historical specimens, characterize antibiotic resistance genes, reconstruct components of the host diet, and recover host genetic profiles. Our work demonstrates that metagenomic analyses of dental calculus can be performed on a diverse range of mammalian species, which will allow the study of oral microbiome and pathogen evolution from a comparative perspective. As dental calculus is readily preserved through time, it can also facilitate the quantification of the impact of anthropogenic changes on wildlife and the environment.

Ancient DNA Reconstructs the Genetic Legacies of Precontact Puerto Rico Communities.

Indigenous peoples have occupied the island of Puerto Rico since at least 3000 BC. Due to the demographic shifts that occurred after European contact, the origin(s) of these ancient populations, and their genetic relationship to present-day islanders, are unclear. We use ancient DNA to characterize the population history and genetic legacies of precontact Indigenous communities from Puerto Rico. Bone, tooth, and dental calculus samples were collected from 124 individuals from three precontact archaeological sites: Tibes, Punta Candelero, and Paso del Indio. Despite poor DNA preservation, we used target enrichment and high-throughput sequencing to obtain complete mitochondrial genomes (mtDNA) from 45 individuals and autosomal genotypes from two individuals. We found a high proportion of Native American mtDNA haplogroups A2 and C1 in the precontact Puerto Rico sample (40% and 44%, respectively). This distribution, as well as the haplotypes represented, supports a primarily Amazonian South American origin for these populations and mirrors the Native American mtDNA diversity patterns found in present-day islanders. Three mtDNA haplotypes from precontact Puerto Rico persist among Puerto Ricans and other Caribbean islanders, indicating that present-day populations are reservoirs of precontact mtDNA diversity. Lastly, we find similarity in autosomal ancestry patterns between precontact individuals from Puerto Rico and the Bahamas, suggesting a shared component of Indigenous Caribbean ancestry with close affinity to South American populations. Our findings contribute to a more complete reconstruction of precontact Caribbean population history and explore the role of Indigenous peoples in shaping the biocultural diversity of present-day Puerto Ricans and other Caribbean islanders.

Exploring late Paleolithic and Mesolithic diet in the Eastern Alpine region of Italy through multiple proxies.

OBJECTIVES: The analysis of prehistoric human dietary habits is key for understanding the effects of paleoenvironmental changes on the evolution of cultural and social human behaviors. In this study, we compare results from zooarchaeological, stable isotope and dental calculus analyses as well as lower second molar macrowear patterns to gain a broader understanding of the diet of three individuals who lived between the end of the Late Pleistocene and the Early Holocene (ca., 17-8 ky cal BP) in the Eastern Alpine region of Italy. MATERIALS AND METHODS: We analyze individuals buried at the sites of Riparo Tagliente (Verona), Riparo Villabruna, and Mondeval de Sora (Belluno). The three burials provide a unique dataset for diachronically exploring the influence of climatic changes on human subsistence strategies. RESULTS: Isotopic results indicate that all individuals likely relied on both terrestrial and freshwater animal proteins. Even though dental calculus analysis was, in part, hindered by the amount of mineral deposit available on the teeth, tooth macrowear study suggests that the dietary habits of the individuals included plant foods. Moreover, differences in macrowear patterns of lower second molars have been documented between Neanderthals and modern humans in the present sample, due to a prevalence of Buccal wear among the former as opposed to higher values of Lingual wear in modern human teeth. DISCUSSION: Isotopic analyses have emphasized the contribution of animal proteins in the diet of the three foragers from the Eastern Alpine region. The possible intake of carbohydrate-rich plant foods, suggested by the retrieval of plant remains in dental calculus, is supported by the signal of macrowear analysis. Moreover, the latter method indicates that the distribution of macrowear in lower second molars (M2 s) allows us to discriminate between Neanderthals and modern humans within the present reference sample. Overall, our results show these three prehistoric hunter-gatherers were well adapted to the environment in which they lived exploiting many natural resources.

The Role of Cytokines Produced via the NLRP3 Inflammasome in Mouse Macrophages Stimulated with Dental Calculus in Osteoclastogenesis.

Dental calculus (DC) is a common deposit in periodontitis patients. We have previously shown that DC contains both microbial components and calcium phosphate crystals that induce an osteoclastogenic cytokine IL-1ß via the NLRP3 inflammasome in macrophages. In this study, we examined the effects of cytokines produced by mouse macrophages stimulated with DC on osteoclastogenesis. The culture supernatants from wild-type (WT) mouse macrophages stimulated with DC accelerated osteoclastogenesis in RANKL-primed mouse bone marrow macrophages (BMMs), but inhibited osteoclastogenesis in RANKL-primed RAW-D cells. WT, but not NLRP3-deficient, mouse macrophages stimulated with DC produced IL-1ß and IL-18 in a dose-dependent manner, indicating the NLRP3 inflammasome-dependent production of IL-1ß and IL-18. Both WT and NLRP3-deficient mouse macrophages stimulated with DC produced IL-10, indicating the NLRP3 inflammasome-independent production of IL-10. Recombinant IL-1ß accelerated osteoclastogenesis in both RANKL-primed BMMs and RAW-D cells, whereas recombinant IL-18 and IL-10 inhibited osteoclastogenesis. These results indicate that DC induces osteoclastogenic IL-1ß in an NLRP3 inflammasome-dependent manner and anti-osteogenic IL-18 and IL-10 dependently and independently of the NLRP3 inflammasome, respectively. DC may promote alveolar bone resorption via IL-1ß induction in periodontitis patients, but suppress resorption via IL-18 and IL-10 induction in some circumstances.