Palaeoproteomics resolves sloth relationships

The living tree sloths Choloepus and Bradypus are the only remaining members of Folivora, a major xenarthran radiation that occupied a wide range of habitats in many parts of the western hemisphere during the Cenozoic, including both continents and the West Indies. Ancient DNA evidence has played only a minor role in folivoran systematics, as most sloths lived in places not conducive to genomic preservation. Here we utilize collagen sequence information, both separately and in combination with published mitochondrial DNA evidence, to assess the relationships of tree sloths and their extinct relatives. Results from phylogenetic analysis of these datasets differ substantially from morphology-based concepts: Choloepus groups with Mylodontidae, not Megalonychidae; Bradypus and Megalonyx pair together as megatherioids, while monophyletic Antillean sloths may be sister to all other folivorans. Divergence estimates are consistent with fossil evidence for mid-Cenozoic presence of sloths in the West Indies and an early Miocene radiation in South America

Eimeriid Oocysts From Archaeological Samples in Patagonia, Argentina

Oocysts attributable to Eimeria macusaniensis Guerrero et al. 1971, were found in coprolites and in archaeological sediments dating to the Holocene of Patagonia, Argentina. By means of a nonparametric regression using a generalized additive model, a significant relationship was found between the size of the oocysts and their antiquity. Specifically, a reduction in oocyst size over time was discovered, probably due to a parasite response to host replacement, to an extinct eimeriid species common during the Pliestocene–Holocene transition, or to environmental changes known for the Holocene. Explanations regarding coevolution between parasites, hosts, and paleoenvironmental conditions are discussed herein

Prenatal diagnosis of congenital toxoplasmosis

Primary Toxoplasmosis is devoid of any consequences in the mother in most cases, while the fetus can suffer serious damages following transplacental passage of the parasite. This is probably due to its limited immunocompetence. 440 women have been seen for suspected primary infection during pregnancy: clinical and serological parameters excluded infection in 62% of the cases. In 168 cases primary infection was likely and they underwent therapy with Spiramycin 3 grams per day to prevent placental and fetal colonization: 53 cases were elected for invasive prenatal diagnosis. Amniotic fluid was obtained by amniocentesis and fetal blood by ultrasound guided cordocentesis and by fetoscopy: the samples were analyzed for specific anti Toxoplasma IgM and sent for isolation of the parasite. Diagnosis of fetal infection was made in 4 cases: 3 cases had specific IgM in cord blood, 1 case showed intracranial calcifications by ultrasound screening. Fetal infection rate is thus below 10% and prenatal diagnosis avoids unjustified interruption of pregnancies complicated by maternal toxoplasmic infection

Prenatal invasive diagnosis for congenital Toxoplasmosis by PCR for specific DNA Toxoplasma sequences

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Invasive prenatal diagnosis for congenital Toxoplasmosis should be offered only to mothers with proven seroconversion?

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