Dental health status of the medieval silver-mining community from Kutná Hora (Czech Republic, 13th-16th c.): Impact of socioeconomic changes and mortality crises.

OBJECTIVE: The aim of the study was to evaluate the pathological conditions in teeth from skeletal remains found in the medieval burial ground at Kutná Hora (13th-16th centuries, Czech Republic). We focused on the effect on dental health of socioeconomic changes associated with the boom in silver mining at the site. DESIGN: In this study, dental caries and antemortem tooth loss were recorded for 469 sexed adults (10,558 permanent teeth). Pathologies were analysed and presented by teeth and alveoli, and the differences between their frequencies were tested in sex-, age-, and burial context-separated groups (mass vs. individual graves). RESULTS: The oral conditions were characterised by a low frequency of caries and moderate frequency of antemortem tooth loss (AMTL). For caries, males and females showed the same frequencies while AMTL comparisons indicated a higher rate in females. Most differences emerged between age-separated and burial context-separated groups. The age progression of the pathologies was confirmed for both caries and AMTL. Skeletons from mass burials had higher caries and AMTL frequencies than those buried in individual graves. CONCLUSIONS: The dataset exhibited low caries and below average AMTL rates compared to other medieval European skeletal series. We think that life in this mining centre had a positive effect on the dental health of its inhabitants. The relatively poorer dental health of those buried in mass graves reflected either the specific composition of the population in the first half of the 14th century or the lower resilience of these individuals when facing mortality crises.

Protocol matters: A need for standardized procedure in cementochronology.

Cementochronology has long been associated in the literature with a high correlation between chronological and estimated age, and low differences between the two ages. The excessive accuracy was rather suspicious, and the method did not even appear in common forensic practice. An important step towards more widespread use of the method is the need to standardize work procedures, including indexes for recording the quality of cementum, preparation of thin sections and the age calculation. In our study, we used the standardized protocol for the preparation of thin sections in a set of Czech modern teeth of known age and sex. In the initial phase, 11.5% of the teeth were discarded due to severe caries in the medial part of the root. In a set of single extractions (55 teeth from 55 individuals), we focused on the detailed results of the age estimation, using precision and accuracy indicators. We also used different dental development data to calculate age, given inconsistencies in the use of eruption / mineralization. In a set of multiple extractions (68 teeth from 22 individuals), intra-individual variability was examined. The result of the application of the standardized protocol is an estimate of age with an absolute inaccuracy of -1.7 years and a relative inaccuracy of 5.4%. Calculation of precision and accuracy in the set of single extractions, however, showed the method's limitations: the imprecision measuring the variability of cementum increments counts increased with chronological age, as did the inaccuracy. The use of different dental development data did not significantly increase the accuracy of the age estimation results. Intra-individual variability remains poorly understood - in the set of multiple extractions the differences within one individual ranged between 0.9 and 10.8 years.

Early medieval diet in childhood and adulthood and its reflection in the dental health of a Central European population (Mikulcice, 9th-10th centuries, Czech Republic).

OBJECTIVES: The aim of this study is to provide a detailed view of dental health in relationship to the diet of the Great Moravian population, with emphasis on childhood diet. DESIGN: We studied skeletal samples of the early medieval population of the Mikulcice agglomeration (Czech Republic) originating from the cemetery of the church VI (91 adults). Stable isotope analysis of carbon and nitrogen (intra-individual sampling - tooth and bone) was performed on this material, and dental characteristics (carious lesions, intensity of caries (I-CE), dental wear, linear enamel hypoplasia) evaluated. RESULTS: Isotopic signals obtained from tooth and bone samples of the same individuals differ significantly. Tooth samples show higher δ13C and lower δ15N than bone samples. δ15N in tooth and bone samples is related to socio-economic status. We discovered a relationship between isotopic signals from tooth or bone and intensity of caries and dental wear. CONCLUSION: We provide the first direct information about the diet of the juvenile part of the Great Moravian population from Mikulcice. The diet of children differed from the diet of adults. Children consumed more millet and less animal protein than adults. The social stratification of this population was obvious in dietary composition from childhood. Elites consumed more animal proteins than non-elite individuals. Tooth decay was related to relative consumption of plant and animal proteins. Greater dental wear is related to a diet based on C3 plants. There was no significant connection between diet composition and the formation of enamel hypoplasia.

Reactions of green lizards (Lacerta viridis) to major repellent compounds secreted by Graphosoma lineatum (Heteroptera: Pentatomidae).

The chemical defence of Heteroptera is primarily based on repellent secretions which signal the potential toxicity of the bug to its predators. We tested the aversive reactions of green lizards (Lacerta viridis) towards the major compounds of the defensive secretion of Graphosoma lineatum, specifically: (i) a mixture of three aldehydes: (E)-hex-2-enal, (E)-oct-2-enal, (E)-dec-2-enal; (ii) a mixture of these three aldehydes and tridecane; (iii) oxoaldehyde: (E)-4-oxohex-2-enal; (iv) secretion extracted from metathoracic scent glands of G. lineatum adults and (v) hexane as a non-polar solvent. All chemicals were presented on a palatable food (Tenebrio molitor larvae). The aversive reactions of the green lizards towards the mealworms were evaluated by observing the approach latencies, attack latencies and approach-attack intervals. The green lizards exhibited a strong aversive reaction to the mixture of three aldehydes. Tridecane reduced the aversive reaction to the aldehyde mixture. Oxoaldehyde caused the weakest, but still significant, aversive reaction. The secretion from whole metathoracic scent glands also clearly had an aversive effect on the green lizards. Moreover, when a living specimen of G. lineatum or Pyrrhocoris apterus (another aposematic red-and-black prey) was presented to the green lizards before the trials with the aldehyde mixture, the aversive effect of the mixture was enhanced. In conclusion, the mixture of three aldehydes had the strong aversive effect and could signal the potential toxicity of G. lineatum to the green lizards.

Influence of Trichobilharzia regenti (Digenea: Schistosomatidae) on the defence activity of Radix lagotis (Lymnaeidae) Haemocytes.

Radix lagotis is an intermediate snail host of the nasal bird schistosome Trichobilharzia regenti. Changes in defence responses in infected snails that might be related to host-parasite compatibility are not known. This study therefore aimed to characterize R. lagotis haemocyte defence mechanisms and determine the extent to which they are modulated by T. regenti. Histological observations of R. lagotis infected with T. regenti revealed that early phases of infection were accompanied by haemocyte accumulation around the developing larvae 2-36 h post exposure (p.e.) to the parasite. At later time points, 44-92 h p.e., no haemocytes were observed around T. regenti. Additionally, microtubular aggregates likely corresponding to phagocytosed ciliary plates of T. regenti miracidia were observed within haemocytes by use of transmission electron microscopy. When the infection was in the patent phase, haemocyte phagocytic activity and hydrogen peroxide production were significantly reduced in infected R. lagotis when compared to uninfected counterparts, whereas haemocyte abundance increased in infected snails. At a molecular level, protein kinase C (PKC) and extracellular-signal regulated kinase (ERK) were found to play an important role in regulating these defence reactions in R. lagotis. Moreover, haemocytes from snails with patent infection displayed lower PKC and ERK activity in cell adhesion assays when compared to those from uninfected snails, which may therefore be related to the reduced defence activities of these cells. These data provide the first integrated insight into the immunobiology of R. lagotis and demonstrate modulation of haemocyte-mediated responses in patent T. regenti infected snails. Given that immunomodulation occurs during patency, interference of snail-host defence by T. regenti might be important for the sustained production and/or release of infective cercariae.

Urban-rural differences in stature in the population of medieval Bohemia.

This study explores differences in stature and their diachronic trends between the urban and rural medieval populations of Bohemia. We estimated stature from the lengths of the long bones of subjects living in Prague (urban) and rural areas of present Czech territory. Our results indicate the absence of significant urban/rural differences in stature in the population living between the 11th and 14th century. For both sexes, the temporal variations in stature in this period show a statistically non-significant decrease in the rural, and increase in the urban, population samples. These findings suggest a uniformity of living conditions in the medieval population in this area of Central Europe. Economic factors causative for urban versus rural stature differences appear later in the Modern Age, probably in relation to industrialization.