32 research outputs found
First Evidence of Reproductive Adaptation to âIsland Effectâ of a Dwarf Cretaceous Romanian Titanosaur, with Embryonic Integument In Ovo
<div><h3>Background</h3><p>The Cretaceous vertebrate assemblages of Romania are famous for geographically endemic dwarfed dinosaur taxa. We report the first complete egg clutches of a dwarf lithostrotian titanosaur, from ToteĹti, Romania, and its reproductive adaptation to the âisland effectâ.</p> <h3>Methodology/Findings</h3><p>The egg clutches were discovered in sequential sedimentary layers of the Maastrichtian Sânpetru Formation, ToteĹti. The occurrence of 11 homogenous clutches in successive strata suggests philopatry by the same dinosaur species, which laid clutches averaging four âź12 cm diameters eggs. The eggs and eggshells display numerous characters shared with the positively identified material from egg-bearing level 4 of the Auca Mahuevo (Patagonia, Argentina) nemegtosaurid lithostrotian nesting site. Microscopic embryonic integument with bacterial evidences was recovered in one egg. The millimeter-size embryonic integument displays micron size dermal papillae implying an early embryological stage at the time of death, likely corresponding to early organogenesis before the skeleton formation.</p> <h3>Conclusions/Significance</h3><p>The shared oological characters between the HaĹŁeg specimens and their mainland relatives suggest a highly conservative reproductive template, while the nest decrease in egg numbers per clutch may reflect an adaptive trait to a smaller body size due to the âisland effectâ. The combined presence of the lithostrotian egg and its embryo in the Early Cretaceous Gobi coupled with the oological similarities between the HaĹŁeg and Auca Mahuevo oological material evidence that several titanosaur species migrated from Gondwana through the HaĹŁeg Island before or during the Aptian/Albian. It also suggests that this island might have had episodic land bridges with the rest of the European archipelago and Asia deep into the Cretaceous.</p> </div
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Non-psoriatic uses of calcipotriol: a concise updated review
Calcipotriol (calcipotriene) is a synthetic vitamin D3 derivative that is a standard treatment option for psoriasis. It is generally well tolerated with minimal side effects. Due to its ability to reduce keratinocyte proliferation and induce keratinocyte differentiation as well as its immunomodulatory effects, calcipotriol has been used to treat a variety of skin disorders such as atopic dermatitis, actinic keratoses, lichen planus, seborrheic keratoses, and vitiligo [1]. We surveyed the literature examining the use of calcipotriol for non-psoriatic dermatologic disease