Gastrointestinal parasite burden in 4th-5th c. CE Florence highlighted by microscopy and paleogenetics.

The study of ancient parasites, named paleoparasitology, traditionally focused on microscopic eggs disseminated in past environments and archaeological structures by humans and other animals infested by gastrointestinal parasites. Since the development of paleogenetics in the early 1980s, few paleoparasitological studies have been based on the ancient DNA (aDNA) of parasites, although such studies have clearly proven their utility and reliability. In this paper, we describe our integrative approach for the paleoparasitological study of an ancient population from Florence in Italy, dated to the 4th-5th c. CE. The first stage consisted in the study of sediment samples from the pelvic area of 18 individuals under light microscopy. This allowed us to detect Ascarid-type eggs belonging very probably to the human-infesting roundworm Ascaris lumbricoides. Ten subsamples were selected corresponding to five individuals, and we extracted their whole DNA following sediment aDNA protocols. A targeted approach allowed us to detect two nematodes and one trematode aDNA fragments, namely Ascaris sp., Trichuris trichiura, and Dicrocoelium dendriticum. Among the five individuals tested for microscopic eggs and aDNA, three of them showed the remains of eggs (only Ascarid-type), but all of them tested positive to the presence of at least one parasite aDNA. Microscopic diagnosis first guided our research for the selection of promising samples while the targeted aDNA approach significantly improved our knowledge in terms of parasitic diversity and frequency in this population subgroup. These results enabled us to discuss the possible impact of latent parasitism in this past population at the time of an epidemic, as suggested in Florence. In particular, the singular case of D. dendriticum detection is discussed in light of the present-day scarcity of genuine human infections. Nevertheless, actual infections are known in the paleoparasitological record, and food habits may have led to false parasitism in this historical context. aDNA leaching from overlying strata may also explain this detection. This study strongly pleads for a systematic integrative approach combining microscopy and aDNA in paleoparasitology.

Study on the Relationship between Liver Parasitic Infections and Serum Vitamin A and ß-Carotene Status in Cattle.

OBJECTIVE: This study was conducted to evaluate the relationship between serum levels of vitamin A and ß-carotene in the liver of cattle. METHODS: A total number of 150 samples were selected according to the type of parasitic infections of the liver after postmortem examination and confirmation. Parasitic lesions in the liver were subdivided into three major parasites, including Fasciola hepatica, Dicrocoelium dendriticum, and hydatid cysts. Fifty samples were obtained from cattle without any parasitic infection as a control group. Serum levels of vitamin A, ß-carotene concentrations (µg/dL), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) activity were assayed. RESULTS: Naturally infected cattle with D. dendriticum, F. hepatica and hydatid cyst showed lower vitamin A levels. Serum ß-carotene levels were significantly decreased in all groups (p<0.05). ALT and AST activities in animals with parasitic diseases were statistically higher than in control group (p<0.01). A significant negative correlation was determined between the ß-carotene, vitamin A levels and enzyme activities of the liver in all the three types of liver infections (p<0.001). CONCLUSIONS: This study indicated that serum levels of vitamin A and ß-carotene decline was present in cattle with liver parasite infection and vitamin supplements should be supplied.

Preliminary protective capacity study of a Dicrocoelium dendriticum antigenic protein in hamsters.

The purpose of this study was to evaluate the protective capacity of 130 kDa Dicrocoelium dendriticum protein in hamsters experimentally infected with this parasite. Forty hamsters divided into four groups of ten animals each were used: G1 (control), G2 (infected), G3 (immunized with Freund's adjuvant and infected), G4 (130 kDa protein vaccinated + adjuvant and infected). Infection with 40 metacercariae/hamster was carried out 4 weeks after the last immunization. Parasitological studies [number of eggs per gram (epg) and worm burden] and biochemical parameters (total proteins, albumin, and total bilirubin), hepatic enzymes [aspartate aminotransferase (AST) and alanine aminotransferase (ALT)], and total IgG levels were determined. A reduction in epg in G3 and G4 was observed 16 weeks postinfection with the higher reduction percentage in the latter (25.2%). No statistically significant differences were detected in the number of recovered worms among groups, although the mean was slightly less in G4 (12.2 +/- 2.08, mean +/- SE) than in G2 (15.4 +/- 2.90). In G4, global protection was 20.9% and an increase in AST and ALT levels was observed. Total IgG levels were similar in the three infected groups. The protection obtained was inadequate, so the antigen dose, immunization-infection period, adjuvants, and immunization route must be optimized.