Association between ancient bone preservation and dna yield: a multidisciplinary approach.

Ancient molecular typing depends on DNA survival in archaeological bones. Finding valuable tools to predict DNA presence in ancient samples, which can be measured prior to undertaking a genetic study, has become an important issue as a consequence of the peculiarities of archaeological samples. Since the survival of DNA is explained by complex interrelations of multiple variables, the aim of the present study was to analyze morphological, structural, chemical, and biological aspects of a set of medieval human bones, to provide an accurate reflection of the state of preservation of the bony components and to relate it with DNA presence. Archaeological bones that yielded amplifiable DNA presented high collagen content (generally more than 12%), low racemization values of aspartic acid (lesser than 0.08), leucine and glutamic acid, low infrared splitting factor, small size of crystallite, and more compact appearance of bone in the scanning electron micrographs. Whether these patterns are characteristic of ancient bones or specific of each burial site or specimen requires further investigation.

Brimonidine-LAPONITE® intravitreal formulation has an ocular hypotensive and neuroprotective effect throughout 6 months of follow-up in a glaucoma animal model.

Intravitreal administration is widely used in ophthalmological practice to maintain therapeutic drug levels near the neuroretina and because drug delivery systems are necessary to avoid reinjections and sight-threatening side effects. However, currently there is no intravitreal treatment for glaucoma. The brimonidine-LAPONITE® formulation was created with the aim of treating glaucoma for extended periods with a single intravitreal injection. Glaucoma was induced by producing ocular hypertension in two rat cohorts: [BRI-LAP] and [non-bri], with and without treatment, respectively. Eyes treated with brimonidine-LAPONITE® showed lower ocular pressure levels up to week 8 (p < 0.001), functional neuroprotection explored by scotopic and photopic negative response electroretinography (p = 0.042), and structural protection of the retina, retinal nerve fibre layer and ganglion cell layer (p = 0.038), especially on the superior-inferior axis explored by optical coherence tomography, which was corroborated by a higher retinal ganglion cell count (p = 0.040) using immunohistochemistry (Brn3a antibody) up to the end of the study (week 24). Furthermore, delayed neuroprotection was detected in the contralateral eye. Brimonidine was detected in treated rat eyes for up to 6 months. Brimonidine-LAPONITE® seems to be a potential sustained-delivery intravitreal drug for glaucoma treatment.