The skeleton of the staghorn coral Acropora millepora: molecular and structural characterization

15 pagesInternational audienceThe scleractinian coral Acropora millepora is one of the most studied species from the Great Barrier Reef. This species has been used to understand evolutionary, immune and developmental processes in cnidarians. It has also been subject of several ecological studies in order to elucidate reef responses to environmental changes such as temperature rise and ocean acidification (OA). In these contexts, several nucleic acid resources were made available. When combined to a recent proteomic analysis of the coral skeletal organic matrix (SOM), they enabled the identification of several skeletal matrix proteins, making A. millepora into an emerging model for biomineralization studies. Here we describe the skeletal microstructure of A. millepora skeleton, together with a functional and biochemical characterization of its occluded SOM that focuses on the protein and saccharidic moieties. The skeletal matrix proteins show a large range of isoelectric points, compositional patterns and signatures. Besides secreted proteins, there are a significant number of proteins with membrane attachment sites such as transmembrane domains and GPI anchors as well as proteins with integrin binding sites. These features show that the skeletal proteins must have strong adhesion properties in order to function in the calcifying space. Moreover this data suggest a molecular connection between the calcifying epithelium and the skeletal tissue during biocalcification. In terms of sugar moieties, the enrichment of the SOM in arabinose is striking, and the monosaccharide composition exhibits the same signature as that of mucus of acroporid corals. Finally, we observe that the interaction of the acetic acid soluble SOM on the morphology of in vitro grown CaCO3 crystals is very pronounced when compared with the calcifying matrices of some mollusks. In light of these results, we wish to commend Acropora millepora as a model for biocalcification studies in scleractinians, from molecular and structural viewpoints

Gynecological adverse effects of natalizumab administration: Case report and review of the literature

Background: Natalizumab is administered for the treatment of relapsing-remitting multiple sclerosis (RR-MS) with high disease activity.Natalizumab therapy has been associated with adverse effects, such as progressive multifocal leukoencephalopathy, liver damage, nasopharyngitis, urinary tract infection, urticaria, cephalgia, dizziness, fatigue, nausea, fever, rigidity, anxiety and gastroenteritis. Objective: To describe a case of a woman with RR-MS who developed recurrent vaginitis on natalizumab administration. Methods: Case report and review of the literature. Results: The case of a 26-year-old Caucasian woman with RR-MS, who presented with recurrent vaginitis since the initiation of treatment with natalizumab, is reported. The patient had a 4-year history of RR-MS; monotherapy with natalizumab (inj. 300 mg/month) came after one year after the initial diagnosis. Since then, she had a history of persistent gynecological infections; the repeated vaginal cultures revealed a variety of underlying pathogens. The patient underwent numerous treatments with local and systematic antibiotics as well as antifungal agents. After the initiation of probiotics and local hygiene measures, recurrences resolved and the patient remains recurrence-free at one-year follow-up. Conclusions: Recurrent vaginitis should be taken into account as a possible adverse effect causing discomfort during long-term natalizumab treatment. Simple measures, such as probiotic administration and meticulous local hygiene, can provide adequate relief for such patients. © 201

Thermal and mechanical properties of modified CaCO3 filled poly (ethylene terephthalate) nanocomposites

Poly(ethylene terephthalate) (PET)/CaCO3 and PET/modified-CaCO3 (m-CaCO3) nanocomposites were prepared by melt blending. The morphology indicated that m-CaCO3 produced by reacting sodium oxalate and calcium chloride, was well dispersed in PET matrix and showed good interfacial interaction with PET compared to CaCO3. No significant differences in the thermal properties such as, glass transition, melting and degradation temperatures, of the nanocomposites were observed. The thermal shrinkage of PET at 120 ??C was 10.8 %, while those of PET/CaCO3 and PET/m-CaCO3 nanocomposites were 2.9-5.2 % and 1.2-2.8 %, respectively depending on filler content. The tensile strength of PET/CaCO3 nanocomposite decreased with CaCO3 loading, whereas that of PET/m-CaCO3 nanocomposites at 0.5 wt% loading showed a 17 % improvement as compared to neat PET. The storage modulus at 120 ??C increased from 1660 MPa for PET to 2350 MPa for PET/CaCO3 nanocomposite at 3 wt% loading, and 3230 MPa for PET/m-CaCO3 nanocomposite at 1 wt% loadinclose0