[Paleoneurology: an evolving science?] / La paléoneurologie - Une science en évolution ?

Title: La paléoneurologie - Une science en évolution ? Abstract: Dans le cadre du Master 2 Sciences du Vivant de l'université EPHE-PSL (cursus IMaGHE, parcours Physiopathologie Intégrative, PPI), des étudiants se sont confrontés à la rédaction d'une Nouvelle scientifique. Selon la spécialisation choisie par les étudiants (Neurosciences ou Cancérologie), l'équipe pédagogique leur a proposé de faire une synthèse d'articles sur deux thématiques : (i) la paléoneurologie, qui permet d'analyser la transformation du cerveau de l'Homme au cours de l'évolution et (ii) la recherche bio-inspirée, qui permet de reproduire ce qui existe dans la nature pour développer des surfaces bactéricides évitant l'usage d'antibiotiques. Organisés en binôme, les étudiants ont rédigé deux Nouvelles qui soulignent l'intérêt des travaux analysés, ainsi que leur originalité. Ils se sont pleinement investis dans cette tâche et ont su faire preuve d'un bel esprit de synthèse. Ils ont apprécié cet exercice nouveau pour eux, mais qui leur a permis d'avoir un aperçu de l'exercice de la publication scientifique, inhérent au métier de chercheur auquel ils se destinent.

Leveraging IsoArcH for isotope paleopathology: The example of the dataset from the Jedlicka collection (Central Europe, 19th century CE).

The article introduces the enhancements made to the IsoArcH database for isotope paleopathology. This includes the addition of new metadata fields, which allow for describing abnormal anatomical or physiological conditions in humans and animals at either the individual or sample level. To showcase the novel features of the database, the article features a unique dataset of carbon and nitrogen isotope values obtained on bulk bone collagen from 42 clinically-documented cases of the Jedlicka pathological-anatomical reference collection, dating from the 19th century CE and curated at the National Museum in Prague, Czechia. The dataset includes 70 combined isotopic measurements from individuals who underwent anatomizations between 1841 and 1900 and had distinct bone diseases/disorders: i.e. syphilis, rickets, osteosarcoma, osteomyelitis, and healed fractures. Finally, the article highlights the value of the data in helping the isotope bioarchaeology and paleopathology communities in their understanding of disease processes.

Development of musculoskeletal deficits in children with cystic fibrosis in later childhood.

Cystic fibrosis (CF) is a genetic condition primarily affecting the respiratory system, with the associated progressive lung damage and loss of function resulting in reduced lifespan. Bone health is also impaired in individuals with CF, leading to much higher fracture risk even in adolescence. However, the development of these deficits during growth and the relative contributions of puberty, body size and muscular loading remain somewhat unexplored. We therefore recruited 25 children with CF (10 girls, mean age 11.3 ± 2.9y) and 147 children without CF (75 girls, mean age 12.4 ± 2.6y). Bone characteristics were assessed using peripheral quantitative computed tomography (pQCT) at 4 % and 66 % distal-proximal tibia. Muscle cross-sectional area (CSA) and density (an indicator of muscle quality) were also assessed at the latter site. Tibial bone microstructure was assessed using high-resolution pQCT (HR-pQCT) at 8 % distal-proximal tibial length. In addition, peak jump power and hop force were measured using jumping mechanography. Group-by-age interactions and group differences in bone and muscle characteristics were examined using multiple linear regression, adjusted for age, sex and pubertal status and in additional models, height and muscle force. In initial models group-by-age interactions were evident for distal tibial total bone mineral content (BMC) and trabecular volumetric bone mineral density (vBMD), with a lower rate of age-related accrual evident in children with CF. In assessments of distal tibial microstructure, similar patterns were observed for trabecular number and thickness, and cortical CSA. In the tibial shaft, group-by-age interactions indicating slower growth in CF were evident for total BMC and cortical CSA, whilst age-independent deficits in CF were observed for several other variables. Peak jump power and hop force also exhibited similar interactions. Group-by-age interactions for bone were partially attenuated at the distal tibia and fully attenuated at the tibial shaft by adjustment for muscle force. These results suggest that bone and muscle deficits in children with CF develop throughout later childhood, independent of differences in pubertal stage and body size. These diverging growth patterns appear to be mediated by differences in muscle function, particularly for bone characteristics in the tibial shaft. Given the high fracture risk in this population from childhood onwards, development of interventions to improve bone health would be of substantial clinical value.

Can the palaeoepidemiology of rickets during the industrialisation period in France be studied through bioarchaeological grey literature and French medico-historical literature of the 18th-early 20th centuries? Preliminary examination of a complex topic.

OBJECTIVE: This study explores whether data relating to rickets from the French medico-historical literature (FMHL) and bioarchaeological grey literature are useful in evaluating its epidemiology during the industrialisation of France. Unlike other European countries such as England, industrialisation in France was a slow and continuous process with two phases: the first in 1830-1870 and the second in 1870-1914. MATERIALS AND METHODS: A bibliographical analysis of 2800 FMHL sources from the 18th to the early 20th centuries and 50 archaeological excavation reports from the last 21 years was undertaken. RESULTS: The FMHL data is very heterogeneous and predominantly dates to the second phase of industrialisation. The bioarchaeological data is very incomplete and predominantly relates to the period before industrialisation. At the same time, knowledge improvement and institutional changes to protect children could explain more systematic registration of cases of rickets. CONCLUSIONS: No solid conclusions can be made regarding the prevalence of rickets at present, however these data hold great potential. SIGNIFICANCE: In comparison to England, no systematic investigation of rickets prevalence during the period of industrialisation in France has been undertaken to date. LIMITATIONS: The lack of archaeological excavations from this period and the limited paleopathological analysis of the sites excavated have contributed to our current lack of understanding regarding the impact of industrialization on the prevalence of rickets on the French population. SUGGESTIONS FOR FURTHER WORK: The FMHL data needs to be homogenized and osteoarchaeological collections need to be restudied with a common protocol focusing on signs of vitamin D deficiency.

Was the rise of TB contemporaneous with the industrial revolution? Epidemiological evolution of TB in France (17th-20th centuries) inferred from osteoarchaeological and historical archives.

OBJECTIVE: The development of tuberculosis is classically associated with the rise of the Industrial Revolution. Our objective is to test this epidemiological hypothesis for populations in France between the 18th and 20th centuries using osteoarchaeological and historical sources. MATERIALS: Osteoarchaeological sources include two skeletal collections from plague epidemics in Provence (1590 and 1722) representing a total of 349 individuals and medical archives dating 1750-1930 from Paris, Lyon, Marseille, Montpellier. METHODS: Paleoepidemiological analysis (crude prevalence rate) of the archeological data, and epidemiological analysis of historical data included the proportional mortality rate of tuberculosis (PMR-TB) and the mortality rate by tuberculosis (MR-TB). RESULTS: Mean prevalence of TB before the 19th century was approximately 30 %, according to osteoarchaeological data. Historical sources showed that pulmonary TB was responsible for 33 % of total deaths in the city of Marseille during the second half of the 18th century and represented about 20 % of deaths in the four French cities during the 19th century. The mortality rate was 6.5 per thousand inhabitants in the 18th century (Marseille) and stable at 4-5 ‰ during the 19th century before, during, and after the Industrial Revolution period, with the exception of years 1870-1871 (French-Prussian war), when it increased. CONCLUSIONS: Population increase contemporary to the industrialization process did not increase the mortality rate by tuberculosis in France. SIGNIFICANCE: The epidemiological assertion that tuberculosis increased with the Industrial Revolution in cities must be reevaluated. In France, and perhaps in other cities, it was an endemic disease at least a century before, and associated with a higher mortality rate. LIMITATIONS: Reliability and biases inherent to archaeological and historical data prior and during the Industrial Revolution must be taken into account. SUGGESTIONS FOR FURTHER RESEARCH: Extension of research to all the French territories (rural and urban areas) is advised.

Are the identified collections of immature skeletons dating from the Industrial Revolution good references for paleoauxological studies? Cases studies from England & France.

OBJECTIVE: Skeletal collections of immature individuals identified by age and sex serve as reference material for studying development in past populations. Several of these collections were established during the Industrial Revolution (IR), a period known for its difficult living conditions in industrial cities. We question if these collections represent useful comparisons from which to explore the natural history of human growth. MATERIALS: Immature individuals from two skeletal collections contemporaneous to the IR period were studied: 71 children from the Spitalfields (UK) and 108 from the Strasbourg (F) collections. Among them we selected mandibles of individuals aged from 0 to 30 months, representing 32 and 52 individuals, respectively. METHODS: We scored the dental development of first and second left deciduous molars according to (Moorrees et al., 1963) stages, from X-rays (Spitalfields) or CT-scans (Strasbourg) data and compared it with the modern reference pattern from the Lewis Growth Records by covariance analysis (ANCOVA). RESULTS: Statistical differences exist in the dental development timeline between the 3 samples. This mainly concerns a delay in the root formation in IR samples that related to post-natal living conditions. CONCLUSIONS: The delay in dental development timeline suggests that growth processes were impacted during IR in England and France, probably due to stressful living conditions. SIGNIFICANCE: keletal collections dating from the IR period in Europe might be not the most appropriate referencesl for studying the natural history of human growth. LIMITATIONS: This study focus on dental development only. SUGGESTIONS FOR FURTHER RESEARCH: Exploring the skeletal growth pattern in other skeletal collections, pre or post-dating the IR, is advised.

Early ontogeny of humeral trabecular bone in Neandertals and recent modern humans.

Trabecular bone ontogeny is well known in modern humans and unknown in Neandertals. Yet the bone developmental pattern is useful for interpreting fossils from evolutionary and functional perspectives. Interestingly, microstructure in early ontogeny is supposedly not influenced by high and specific mechanical loading related to the lifestyle of a human group and consequently does not directly depend on the activities of hunter-gatherers. Here, we specifically explored the early growth trajectories of the trabecular bone structure of the humerus and emphasized in particular how bone fraction (bone volume/total volume [BV/TV]) was built up in Neandertals, given the specific modern human bone loss after birth and the use of BV/TV in functional studies. Six Neandertals and 26 recent modern humans ranging from perinates to adolescents were included in this study. Six trabecular parameters were measured within a cubic region of interest extracted from the proximal metaphysis of the humerus. We found that the microstructural changes in Neandertals during early ontogeny (<1 year) fit with modern human growth trajectories for each parameter. The specific bone loss occurring immediately after birth in modern humans also occurred in Neandertals (but not in chimpanzees). However, the early childhood fossil Ferrassie 6 presented unexpectedly high BV/TV, whereas the high BV/TV in the Crouzade I adolescent was predictable. These results suggest that Neandertals and modern humans shared predetermined early growth trajectories and developmental mechanisms. We assume that the close relationship between skeletal characteristics in early ontogeny and adults in modern humans also existed in Neandertals. However, it was difficult to ensure that the high BV/TV in Neandertal early childhood, represented by only one individual, was at the origin of the high BV/TV observed in adults. Consequently, our study does not challenge the mechanical hypothesis that explains the trabecular gracilization of the humerus during the Holocene.

Sensationalism and speaking to the public: Scientific rigour and interdisciplinary collaborations in palaeopathology.

OBJECTIVES: In this brief communication we discuss issues concerning scientific rigour in palaeopathological publications, particularly studies published in clinical or general science journals, that employ skeletal analysis to elucidate the lives and deaths of historical figures or interpret "mysterious" assemblages or burials. We highlight the relationship between poor methodological rigour and lack of interdisciplinary communication, and discuss how this can result in scientifically weak, sensational narratives being presented to the public. CONCLUSIONS: Although most high profile publications involving analysis of archaeological human remains are methodologically sound and well interpreted, others have suffered from poor scientific rigour stemming from an apparent lack of awareness of anthropological methods and ethics. When these publications are highlighted by the press, sensationalistic narratives are perpetuated which may reflect poorly on our discipline and give the public unrealistic expectations about our work. SUGGESTIONS FOR FUTURE RESEARCH: We suggest that best practice in high-profile paleopathological research include recruitment of a range of authors and reviewers from clinical sciences, anthropology, and the humanities, consideration of the ethical issues surrounding retrospective diagnosis, and transparency with the press in regards to the limitations inherent in this kind of work.

Trabecular bone microarchitecture analysis, a way for an early detection of genetic dwarfism? Case study of a dwarf mother's offspring.

A 66 year-old woman with a disproportionate dwarfism and who bore seven children was discovered at the Middenbeemster archaeological site (The Netherlands). Three are perinates and show no macroscopic or radiological evidence for a FGFR3 mutation causing hypo-or achondroplasia. This mutation induces dysfunction of the growth cartilage, leading to abnormalities in the development of trabecular bone. Because the mutation is autosomal dominant, these perinates have a 50% risk of having been affected. This study determines whether trabecular bone microarchitecture (TBMA) analysis is useful for detecting genetic dwarfism. Proximal metaphyses of humeri were µCT-scanned with a resolution of 7-12 µm. Three volumes of interest were segmented from each bone with TIVMI© software. The TBMA was quantified in BoneJ© using six parameters on which a multivariate analysis was then performed. Two of the Middenbeemster perinates show a quantitatively different TBMA organization. These results and the family's medical history suggest a diagnosis of genetic dwarfism for this two perinates. This study provides evidence to support the efficacy of µCT for diagnosing early-stage bone disease.

Langerhans cell histiocytosis or tuberculosis on a medieval child (Oppidum de la Granède, Millau, France - 10th-11th centuries AD).

In 2008, a skeleton of a 1 - 2.5-year-old child radiocarbon dated from the 10th - 11th century AD was discovered on the oppidum of La Granède (Millau, France). It presents multiple cranial osteolytic lesions having punched-out or geographical map-like aspects associated with sequestrum and costal osteitis. A multi 3D digital approach (CT, µCT and virtual reconstruction) enabled us to refine the description and identify the diploic origin of the lytic process. Furthermore, precise observation of the extent of the lesions and associated reorganization of the skeletal micro-structure were possible. From these convergent pieces of evidence, the differential diagnosis led to three possibilities: Langerhans cell histiocytosis, tuberculosis, or Langerhans cell histiocytosis and tuberculosis.