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Sex estimation from skeletal remains is one of the crucial issues in forensic anthropology. Long bones can be a valid alternative to skeletal remains for sex estimation when more dimorphic bones are absent or degraded, preventing any estimation from the first intention methods. The purpose of this study was to generate and compare classification models for sex estimation based on combined measurement of long bones using machine learning classifiers. Eighteen measurements from four long bones (radius, humerus, femur, and tibia) were taken from a total of 2141 individuals. Five machine learning methods were employed to predict the sex: a linear discriminant analysis (LDA), penalized logistic regression (PLR), random forest (RF), support vector machine (SVM), and artificial neural network (ANN). The different classification algorithms using all bones generated highly accuracy models with cross-validation, ranging from 90 to 92% on the validation sample. The classification with isolated bones ranked between 83.3 and 90.3% on the validation sample. In both cases, random forest stands out with the highest accuracy and seems to be the best model for our investigation. This study upholds the value of combined long bones for sex estimation and provides models that can be applied with high accuracy to different populations.
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BACKGROUND: Introduction of 1 Treponema pallidum complex pathogen in naive European populations following the return of Christopher Columbus' troops from Central America in 1493 is a central dogma in venereology. METHODS: Among skeletal elements from the seventh or eighth century uncovered in Roquevaire, France, individual RS-1003 femur macroscopically suspected of having an infectious disease was investigated by means of paleoautoimmunohistochemistry, direct metagenomics, and paleoserology, along with 1 control femur from an apparently healthy individual (R-1003) and experimental negative controls. RESULTS: RS-1003 femur showed infectious bone; paleoautoimmunohistochemistry of the lesions led to microscopic detection of a T. pallidum complex pathogen. Phylogenetic analyses comprising 71 T. pallidum complex-specific reads covering 2.37% of the T. pallidum subsp. pallidum reference genome sequence revealed an ancestral T. pallidum complex pathogen in the lesion. Paleoserology detecting T. pallidum-specific antigens confirmed positive serological findings in individual RS-1003. Individual R-1003 and the negative controls remained negative. CONCLUSIONS: This case, predating by 8 centuries previous detections of T. pallidum complex treponematosis in Europe, indicated that European populations were not naive to these pathogens before the 1493 introduction of a Central American T. pallidum complex pathogen overwhelming the T. pallidum ones previously circulating in the Old World. These data break a century-old dogma in medical microbiology.
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Sífilis , Treponema pallidum , Humanos , Treponema pallidum/genética , Sífilis/diagnóstico , Filogenia , Europa (Continente) , FrançaRESUMO
In France, bioarcheological research has long overlooked the early and late modern periods, which witnessed major transformations impacting population structure and leading to the dawn of modern industrialized societies. Two recently excavated large cemeteries in Provence present a unique opportunity to investigate on a large scale the impact on health and living conditions brought about by the Industrial Revolution and consequently track health status changes from the 16th to the early 20th century. The sample includes 642 individuals from the early modern cemetery of Saint-Jacques, La Ciotat (1581-1831) and the late modern cemetery of Les Crottes, Marseille (1784-1905). This study aims to document dental health markers and compare the results between both assemblages, considering ante-mortem tooth loss, wear, caries, abscesses, calculus, periodontitis and linear enamel hypoplasia. The available archaeological and historical sources for these recent periods provide a full documentation in which to interpret and discuss the biological analysis, thus enabling an inclusive bioarcheological approach. RESULTS: revealed similarities between both samples. Differences are more subtle than expected and are seen through the increase in carious lesions and in linear enamel hypoplasia. The former seem to indicate changes in diet with the introduction of new foodstuffs and manufacturing processes during the Industrial Revolution. The latter could reflect the increase in early childhood stress, perhaps due to new feeding practices around weaning and breastfeeding or a poorly diversified diet. Finally, the increasing number of stress events could suggest a noxious sanitary and infectious environment. During the 19th century, Marseille experienced strong demographic and urban growth, resulting in overcrowded areas where sanitation facilities were insufficient or absent. Moreover, the activity of this important trading seaport might have promoted the transmission and appearance of epidemic diseases despite scientific and medical advances, which would have a real impact only from the 20th century onwards.
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Dieta , Comportamento Alimentar , Pré-Escolar , França , Nível de Saúde , História do Século XVII , Humanos , DesmameRESUMO
OBJECTIVES: Depicting past epidemics currently relies on DNA-based detection of pathogens, an approach limited to pathogens with well-preserved DNA sequences. We used paleoserology as a complementary approach detecting specific antibodies under a mini line-blot format including positive and negative control antigens. METHODS: Mini line blot assay incorporated skim milk as negative control, Staphylococcus aureus as positive control, and antigens prepared from lice-borne pathogens Rickettsia prowazekii, Borrelia recurrentis, Bartonella quintana, and Yersinia pestis. Paleoserums were extracted from rehydrated dental pulp recovered from buried individuals. Mini line blots observed with the naked eye, were quantified using a scanner and appropriate software. Paleoserology was applied to the indirect detection of lice-borne pathogens in seven skeletons exhumed from a 16th-17th century suspected military burial site (Auxi-le-Château); and 14 civils exhumed from a 5th-13th century burial site (Saint-Mont). Direct detection of pathogens was performed using quantitative real-time PCR. RESULTS: In Auxi-le-Château, paleoserology yielded 7/7 interpretable paleoserums including 7/7 positives for B. recurrentis including one also positive for B. quintana. In Saint-Mont, paleoserology yielded 8/14 interpretable paleoserums and none reacted against any of the four pathogens. Antibodies against R. prowazekii and Y. pestis were not detected. The seroprevalence was significantly higher in the military burial site of Auxi-le-Château than in the civil burial site of Saint-Mont. Real-time PCR detection of B. quintana yielded 5/21 positive (3 at Saint-Mont and 2 at Auxi-le-Château) whereas B. recurrentis was not detected. CONCLUSIONS: Paleoserology unmasked an outbreak of relapsing B. recurrentis fever in one 16th - 17th century military garrison, missed by real-time PCR. Paleoserology offers a new tool for investigating past epidemics, in complement to DNA sequence-based approaches.
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Anticorpos Antibacterianos/análise , Surtos de Doenças/história , Febre Recorrente , Doenças Transmitidas por Vetores , Adulto , Animais , Bactérias/genética , Bactérias/imunologia , Sepultamento/história , DNA Bacteriano/genética , Polpa Dentária/química , Polpa Dentária/microbiologia , França , História do Século XVI , Humanos , Masculino , Paleopatologia , Ftirápteros , Febre Recorrente/epidemiologia , Febre Recorrente/história , Febre Recorrente/microbiologia , Estudos Soroepidemiológicos , Doenças Transmitidas por Vetores/epidemiologia , Doenças Transmitidas por Vetores/história , Doenças Transmitidas por Vetores/microbiologiaRESUMO
PURPOSE: Syphilis, caused by Treponema pallidum subspecies pallidum , is considered as an old disease affecting humans; traces of such infections, including congenital syphilis, are potentially identifiable in archaeological samples. The aim of this research was to perform macroscopic and molecular investigations of T. pallidum on six infant remains, buried between 1837 and 1867, from the cemetery of 'Les Crottes' in Marseille city (southeastern France). METHODOLOGY: Pathological analysis of bones from individuals, aged from the twenty-ninth week of amenorrhea to 4-9 months, was performed. Samples served also as a source of ancient DNA (aDNA) for PCR-based molecular investigations targeting T. pallidum DNA; all samples were also tested for Mycobacterium tuberculosis and Plasmodium falciparum DNA. Sequences characterized were cloned and sequenced, and compared to those available in databases.Results/Key findings. All samples tested displayed widespread osteoporotic lesions across the skeleton possibly related to some metabolic or infectious disorders. Subsequent molecular analysis revealed that one individual, SP332 (unborn, 29 amenorrhea weeks, inhumation date 1864-1866), exhibited positive signals for the five T. pallidum amplification systems tested; sequence analysis provided strong evidence for the effective detection of T. pallidum subspecies pallidum DNA. CONCLUSIONS: Individual SP332 is the first PCR-confirmed palaeopathological case of syphilis identified in France, and the youngest specimen ever to be diagnosed with certainty for congenital syphilis. Future research aimed at better characterizing this 150-year-old treponeme genome and exploring new archaelogical cases of syphilis in the very young should contribute to a better comprehension of the disease's history.
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DNA Antigo/isolamento & purificação , Sífilis Congênita/microbiologia , Treponema pallidum/isolamento & purificação , Arqueologia , Cemitérios , Feto/microbiologia , França , História do Século XIX , Humanos , Lactente , Mycobacterium tuberculosis/genética , Plasmodium falciparum/genética , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Sífilis Congênita/história , Treponema pallidum/classificaçãoRESUMO
Major manifestations of vertebral degenerative joint disease were observed on a Pre-Columbian Muisca series from the Soacha Cemetery (11th to 13th centuries) Colombia, South America. In total, 1,646 vertebrae of 83 individuals were examined. Osteophytes, vertebral body joint surface contour change ("lipping"), and vertebral body pitting were evaluated for each vertebral body. For apophyseal joints, joint surface contour change, pitting, and eburnation were recorded. Two methods of frequency calculation and five for vertebral degenerative disease diagnosis were applied and compared, allowing discussion of methodological considerations. Our study showed that 83% of individuals and 32% of vertebrae were classified as positive when diagnosed by the presence of at least one of the following manifestations: osteophytes, vertebral body joint surface contour change ("lipping"), apophyseal joint surface contour change, or eburnation (method called "Pitting excluded"). No significant differences were found between the sexes. In the youngest cohort (15-30 years), 65% of individuals and 10% of vertebrae exhibit at least one of the previously mentioned manifestations. High prevalences suggest a high level of physical activity beginning in childhood which may have accelerated the aging process in this Pre-Columbian population. Historical data are compatible with this hypothesis.
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Indígenas Sul-Americanos/história , Artropatias/diagnóstico , Artropatias/epidemiologia , Artropatias/patologia , Osteofitose Vertebral/patologia , Coluna Vertebral/patologia , Fatores Etários , Colômbia/epidemiologia , Feminino , História Medieval , Humanos , Artropatias/complicações , Masculino , Prevalência , Osteofitose Vertebral/etiologiaRESUMO
BACKGROUND: Many soldiers in Napoleon's Grand Army died of infectious diseases during its retreat from Russia. Because soldiers were commonly infested with body lice, it has been speculated that louse-borne infectious diseases, such as epidemic typhus (caused by Rickettsia prowazekii), were common. METHODS: We investigated this possibility during recent excavations of a mass grave of Napoleon's soldiers in Vilnius, Lithuania. Segments of 5 body lice, identified morphologically and by polymerase chain reaction (PCR) amplification and sequencing, were found in earth from the grave that also contained fragments of soldiers' uniforms. RESULTS: DNA of Bartonella quintana (the agent of trench fever) was identified by PCR and sequencing in 3 of the lice. Similarly, PCR and sequencing of dental pulp from the remains of 35 soldiers revealed DNA of B. quintana in 7 soldiers and DNA of R. prowazekii in 3 other soldiers. CONCLUSIONS: Our results show that louse-borne infectious diseases affected nearly one-third of Napoleon's soldiers buried in Vilnius and indicate that these diseases might have been a major factor in the French retreat from Russia.