Mycobacterium leprae diversity and population dynamics in medieval Europe from novel ancient genomes.

BACKGROUND: Hansen's disease (leprosy), widespread in medieval Europe, is today mainly prevalent in tropical and subtropical regions with around 200,000 new cases reported annually. Despite its long history and appearance in historical records, its origins and past dissemination patterns are still widely unknown. Applying ancient DNA approaches to its major causative agent, Mycobacterium leprae, can significantly improve our understanding of the disease's complex history. Previous studies have identified a high genetic continuity of the pathogen over the last 1500 years and the existence of at least four M. leprae lineages in some parts of Europe since the Early Medieval period. RESULTS: Here, we reconstructed 19 ancient M. leprae genomes to further investigate M. leprae's genetic variation in Europe, with a dedicated focus on bacterial genomes from previously unstudied regions (Belarus, Iberia, Russia, Scotland), from multiple sites in a single region (Cambridgeshire, England), and from two Iberian leprosaria. Overall, our data confirm the existence of similar phylogeographic patterns across Europe, including high diversity in leprosaria. Further, we identified a new genotype in Belarus. By doubling the number of complete ancient M. leprae genomes, our results improve our knowledge of the past phylogeography of M. leprae and reveal a particularly high M. leprae diversity in European medieval leprosaria. CONCLUSIONS: Our findings allow us to detect similar patterns of strain diversity across Europe with branch 3 as the most common branch and the leprosaria as centers for high diversity. The higher resolution of our phylogeny tree also refined our understanding of the interspecies transfer between red squirrels and humans pointing to a late antique/early medieval transmission. Furthermore, with our new estimates on the past population diversity of M. leprae, we gained first insights into the disease's global history in relation to major historic events such as the Roman expansion or the beginning of the regular transatlantic long distance trade. In summary, our findings highlight how studying ancient M. leprae genomes worldwide improves our understanding of leprosy's global history and can contribute to current models of M. leprae's worldwide dissemination, including interspecies transmissions.

Dental disease in a 15th-17th centuries skeletal sample of enslaved Africans (Lagos, Portugal).

OBJECTIVE: Dental disease is frequently used as a proxy for diet and overall health of individuals of past populations. The aim of this study is to investigate dental disease in a sample of enslaved African individuals recovered from an urban dump (15th-17th centuries) in Lagos, Portugal. DESIGN: In all, 81 African individuals (>12 years old) were analysed (19 males, 49 females, and 13 of unknown sex), in a total of 2283 alveoli, 2061 teeth, and 2213 interdental septa. Analysed oral pathologies include dental caries, periodontal disease, and ante-mortem tooth loss. Dental wear was also recorded. RESULTS: Dental caries affected 52.0 % of the teeth, although only 31.9 % were cavitated lesions. In all, 96.3 % of the individuals presented at least one cariogenic lesion. Gingivitis and periodontitis were recorded in 56.7 % and 19.0 % of the septa, respectively. Only one male individual had all septal areas healthy. Ante-mortem tooth loss was recorded in 38.3 % of the individuals, in a total of 96 teeth lost (4.2 %). Regarding occlusal wear, 70.8 % of the surfaces were recorded with grades 1-3. CONCLUSIONS: The frequencies of the oral pathological conditions observed may not only reflect a cariogenic diet (rich in starches and with a high frequency of meals) but also the conditions during the maritime voyage of the first victims of the North Atlantic slave trade (xerostomia due to lack of water, sea sickness and vomiting, vitamin C deficiency, poor hygiene), and also the impact intentional dental modifications had on the dentitions.

Multi-headed (bifid and trifid) mandibular condyles in archaeological contexts: Two posttraumatic cases.

OBJECTIVE: Bifid and trifid mandibular condyles are infrequent morphological alterations of the mandibular condyle. With the aim of better identifying its possible causing factors in the past and provide clues on the potential types and severities of joint dysfunction that may occur if clinical intervention is not undertaken, two archaeological cases of multi-headed mandibular condyles are presented, and their possible aetiology and pathogenesis are discussed. DESIGN: In this study, 143 adult mandibles recovered in the northwest of Spain were examined: 91 exhumed from San Juan Bautista church (Guardo, Palencia; 16th-19th centuries), and 52 from San Salvador de Palat de Rey church (León, 13th-19th centuries). All mandibles were observed macroscopically for the presence of any morphological and/or pathological alterations. When justified, the mandibles were also scrutinized through computed tomography. RESULTS: Two isolated mandibles (n = 1, Palencia; n = 1, León) with multi-headed mandibular condyles (bifid and trifid) were identified. The computed tomography scan of the affected mandibles revealed alterations compatible with traumatic events, namely line fractures and deformations at the angle of the mandible. CONCLUSIONS: Both the bifid and trifid mandibular condyles here described probably result from traumatic events during childhood leading to a posttraumatic deformation. Although no severe impairment of mandibular use was identified, some asymmetries probably resulted in some sort of malfunction, with TMJ-OA and gonial angle eversion as supporting evidence. Nevertheless, the degree of bone remodelling observed indicates that both individuals lived long after the traumatic occurrence.

Periodontal disease in a Portuguese identified skeletal sample from the late nineteenth and early twentieth centuries.

Periodontal status was investigated in 600 adult dentitions belonging to the identified osteological collections curated at the University of Coimbra, Portugal. These collections date to a point temporally intermediate between the large epidemiological studies of the 20th century and archaeological collections that antedate the 19th century. The aim of this study is to compare periodontal data derived from contemporary samples with statistics compiled from epidemiological studies to determine if factors such as age-at-death, sex, and tooth type are essential or not to account for in future archaeological studies of periodontitis. Periodontal disease status was assessed based on the textural and architectural variations of the interdental septum and the extent of bone loss. Overall, the frequency of periodontitis within the Coimbra collections is 73.8%. Men were more susceptible to periodontal disease than women. Gingivitis was widespread in the younger age groups. Destructive periodontitis was observed early in adulthood, rising steadily with age. The most susceptible sites to periodontal breakdown were located in the posterior region of the upper jaw. Some variation in reported frequencies of periodontitis was found in epidemiological reports, which might result from variation in methods for identifying the pathology, differences in the age composition of the samples examined, variation in oral hygiene and/or diet, or some other factors. Regarding the pattern of distribution of periodontal disease, Coimbra results were similar to comparable modern epidemiological surveys, making clear the importance of considering sex, age, and oral distribution of periodontitis in future archaeological studies.

A possible case of ameloblastoma in an adult male from the early 20th century Coimbra, Portugal.

OBJECTIVE: This article discusses the differential diagnosis of an unusual lesion found in the mandible of an adult male individual (late 19th to early 20th century). MATERIALS: A cranium from the Identified Skulls Collection Escolas Médicas of the University of Coimbra, Portugal. METHODS: Macroscopic analysis, conventional radiography. RESULTS: Macroscopically, a conspicuous osteolytic lesion was identified in the middle vestibular area of the mandible. The conventional radiography examination revealed a multilocular and non-expansive lesion, with undefined contours and irregular walls. CONCLUSIONS: These characteristics are compatible with a benign lesion, possibly an ameloblastoma or an odontogenic keratocyst. SIGNIFICANCE: The present work contributes substantially to the knowledge of the development of cystic and tumour lesions in the past and generates a broader body of knowledge about these lesions. LIMITATIONS: Destructive methods were not authorized. SUGGESTIONS FOR FURTHER RESEARCH: In the future, computed tomography scans and 3D reconstruction analysis, not performed in the current study, may add new and valuable information.

Osseous mass in a maxillary sinus of an adult male from the 16th-17th-century Spain: Differential diagnosis.

OBJECTIVE: To undertake a differential diagnosis of a large mass found in the left maxillary sinus of a cranium dated to the 16th-17th-century, and to expand knowledge of the diagnosis of osseous tissue formation in osteoarchaeological studies. MATERIAL: A cranium recovered from the cemetery of San Salvador de Palat de Rey church, León (Spain). METHODS: Macroscopic analysis, CT scanning. RESULTS: Macroscopic analysis indicated that the individual was probably a male over 30 years old with an ossified mass in the left maxillary sinus, measuring 24 × 19 × 24 mm, occupying approximately 27 % of the maxillary antrum. Computed tomography revealed a well-demarcated radiolucent unilocular mass with some radiopaque areas, with no communication with the alveoli of the premolars or molars. No erosive lesions or signs of inflammation were found. CONCLUSIONS: Neither the macroscopic, nor the radiological characteristics are compatible with inflammatory or malignant pathology, favoring a diagnosis of ossifying fibroma. SIGNIFICANCE: This case adds to the few reported cases in the osteoarchaeological literature, especially since there is limited relevant reference data to assist diagnosis. The CT scans and 3D reconstruction presented here facilitate differential diagnosis in future paleopathological studies. LIMITATIONS: Destructive methods were not authorized. SUGGESTIONS FOR FURTHER RESEARCH: In the future, micro-CT analysis, which was not performed in the current study, may add new and valuable information.

Stafne's bone defects from Spain: report of four cases and brief archaeological literature review.

OBJECTIVE: To present for the first time in the north-western Spanish osteological record prevalence data on Stafne's bone defect, to compare the results with those reported by other studies, and to increase the dataset for future inter-population comparisons. MATERIAL: In all, 143 complete adult mandibles recovered from two necropolises were analyzed (n = 118, San Juan Bautista of Guardo, Palencia province, 16th-19th centuries; n = 25, Plaza del Grano, city of León, 12th-15th centuries). METHODS: Differential diagnosis of the lesions was made through macroscopic and Computed Tomography (CT) analyses. RESULTS: Four mandibles (n = 3, Guardo, Palencia; n = 1, León) presented bone cavities on the lingual aspect of the mandible below the mylohyoid channel, between the first molar and the angle of the mandible. CT scan showed unilateral well-defined unilocular oval/round concavities in the lingual mandibular cortex below the inferior alveolar canal. Neither the macroscopic nor the radiological characteristics are compatible with inflammatory or malignant pathology, favoring instead a diagnosis of Stafne's bone defect. CONCLUSIONS: Four cases of Stafne's defects are added to the bioarchaeological inventory. The calculated prevalence is 2.54% for San Juan Bautista and 4% for Plaza del Grano, values in close agreement to those presented in other osteoarchaeological studies. SIGNIFICANCE: The identification of all examples of Stafne's bone defects in past populations will contribute to elucidate which factors may be responsible for this trait's cultural, ecological, temporal, and geographical patterning. LIMITATIONS: The skeletal samples are relatively small. SUGGESTIONS FOR FURTHER RESEARCH: In future investigations of Stafne's bone defects, CT analysis of dry bone specimens is recommended, whenever possible.

Dental caries in a Portuguese identified skeletal sample from the late 19th and early 20th centuries.

Dental caries was investigated in 600 adult dentitions belonging to the identified osteological collections of the Museum of Anthropology, University of Coimbra, Portugal (late 19th/early 20th centuries). The main advantage of this sample compared to an archaeological source is the presence of known demographic parameters such as age, sex, and occupation. The aim of this study is to investigate the issues involved in comparing caries data derived from archaeological death assemblages with statistics compiled from clinical studies of the living. When only the upper dentition was considered, higher rates were observed in females than in males. No differences were found between sexes for lower teeth. In both sexes, both the percentage of carious teeth and the severity of lesions were found to increase with age, demonstrating that caries activity continued throughout life. The slight decrease observed for the age group 70-79 years is probably due to the increased antemortem tooth loss in the elderly. Caries was most common at contact areas (32.9%) and rarest at smooth crown surfaces (6.5%). Root surface caries was graphed in relation to the exposure of roots, and it was confirmed that the degree of root exposure was not strongly related to the frequency of carious lesions on the exposed root surface, although both increased with age. Molars were attacked more frequently by caries as a whole than premolars, canines or incisors. The results are similar to studies of recent living populations with a limited access to professional dental care.

Evidences of trauma in adult African enslaved individuals from Valle da Gafaria, Lagos, Portugal (15th-17th centuries).

The aim of this work is to discuss the frequency of traumatic bone injuries in a quite unique skeletal assemblage of enslaved people from Valle da Gafaria, Lagos, Portugal (15th-17th centuries). In all, 30 males, 58 females, and 15 individuals of unknown sex were included in the study. The skeletal remains were macroscopically observed for traumatic lesions. When present, the traumatic bone injuries were classified as having occurred ante or perimortem. The antemortem lesions were also studied through radiological analysis. Traumatic lesions were identified in 11 men (36.7%), 23 women (39.7%) and two individuals of unknown sex (13.3%). From these 36 individuals, 61.1% presented antemortem trauma, 25.0% perimortem trauma and 13.9% exhibited simultaneously ante and perimortem trauma. The mechanism of all traumatic injuries was blunt force trauma. From the 9965 analysed bones, 186 exhibited traumatic lesions (87 antemortem, 97 perimortem, and two with both ante and perimortem lesions). The bone more affected by antemortem trauma was the 5th right intermediate foot phalange (40.0%) and by perimortem trauma was the skull (11.4%), probably related to accidents and interpersonal violence, respectively. When analysed by sex, the only significant differences were found in the skull and the right 5th proximal foot phalanges, men (57.1%) presenting more lesions than women (15.4%). The obtained results are consistent with an arduous life, corroborating historical sources which document labour accidents, physical punishments and hard work in the populations of slaves.

Ovarian teratoma: A case from 15th-18th century Lisbon, Portugal.

This paper discusses the differential diagnosis of an unusual calcified mass found in the pelvic cavity of 45+-year-old female excavated from 15th-18th century Lisbon (Portugal). The mass is relatively large, irregularly shaped, and exhibits a concave base with malformed teeth embedded within its inner surface. Considering its macroscopic and radiological characteristics, several conditions were considered in the differential diagnosis, namely eccyesis, fetus in fetu, lithopaedion, and ovarian teratoma. However, the morphological features of the specimen, such as its structure, morphology, and dimensions, are diagnostic of a teratoma. Its location and the sex of the individual are more specifically compatible with a calcified ovarian teratoma. With regional and temporal variations in the frequency of tumours, the report of new cases becomes imperative, especially from geographic regions where few cases have been identified. In fact, this appears to be the first case of ovarian teratoma detected in the Portuguese archaeological record and adds to the few palaeopathological cases described in the osteoarchaeological literature worldwide.