ABSTRACT
Recent advantages in paleomicrobiology have provided an opportunity to investigate the composition of ancient microbial ecologies. Here, using metagenome analysis, we investigated the microbial profiles of historic dental calculus retrieved from archaeological human remains from postmedieval Latvia dated 16-17th century AD and examined the associations of oral taxa and microbial diversity with specific characteristics. We evaluated the preservation of human oral microbiome patterns in historic samples and compared the microbial composition of historic dental calculus, modern human dental plaque, modern human dental calculus samples and burial soil microbiota. Overall, the results showed that the majority of microbial DNA in historic dental calculus originated from the oral microbiome with little impact of the burial environment. Good preservation of ancient DNA in historical dental calculus samples has provided reliable insight into the composition of the oral microbiome of postmedieval Latvian individuals. The relative stability of the classifiable oral microbiome composition was observed. Significant differences between the microbiome profiles of dental calculus and dental plaque samples were identified, suggesting microbial adaptation to a specific human body environment.
Subject(s)
DNA, Bacterial/genetics , Dental Calculus/microbiology , Dental Plaque/microbiology , Microbiota/genetics , Adolescent , Adult , Archaeology , Body Remains , Burial , Child , DNA, Ancient/analysis , Dental Calculus/genetics , Dental Plaque/genetics , Female , Humans , Latvia/epidemiology , Male , Metagenome/genetics , Middle Aged , Soil Microbiology , Young AdultABSTRACT
OBJECTIVE: This article presents long-term follow-up after use of topical photodynamic therapy (PDT) for basal cell carcinoma. PDT is treatment option for different tumors, involving use of specific agent which is activated by visible light and results in tissue destruction. MATERIALS AND METHODS: Overall 20 patients with 29 tumors were treated at the Latvian Oncology Center. Two illumination techniques were used: superficial for smaller lesions and multifiber contact for nodular tumors. Clinical outcome was evaluated at 1, 7, 44 months and 10 years after procedure. RESULTS: By 10 year follow up, there were 2 tumor recurrences and in one case there was tumor residual tissue after first PDT treatment. Overall after ten years follow-up complete response was 80% of cases. CONCLUSION: Data in this study supports hypothesis that PDT could be used for the treatment of non-invasive (superficial and nodular) basal cell carcinoma. Results in this study correspond with similar long-term follow-up studies.
