Syringeable self-assembled cyclodextrin gels for drug delivery.

The design of syringeable cyclodextrin (CD) gels is a developing area in the drug delivery and tissue engineering fields, since they offer the possibility of being administered with minimally invasive maneuvers to form depots that can remain for prolonged time in the implantation site. Two different supramolecular systems can be obtained exploiting the capability of CDs to form inclusion complexes. (i) The threading of free CDs on certain blocks or side chains of copolymers leads to polypseudorotaxanes, which can assembly via regular stacking of the threaded CDs.

Poloxamine-cyclodextrin-simvastatin supramolecular systems promote osteoblast differentiation of mesenchymal stem cells.

Osteogenic/osteoinductive systems combine simvastatin, poloxamine Tetronic 908 (T908) and α-cyclodextrins (αCDs) in a supramolecular network that enhances the solubility/stability of the simvastatin hydroxy acid form and synergistically promotes osteoblast differentiation. Incorporation of 5% αCD transforms dilute T908 solutions (as low as 2% copolymer) into gels, enhances the osteoinductive activity of T908, and provides simvastatin sustained release for more than one week, which results in higher and more prolonged alkaline phosphatase (ALP) activity. The performance of the intrinsically osteoinductive polypseudorotaxane scaffold can be easily tuned by modifying the concentrations of T908, αCD, and simvastatin in a certain range of values.

Acute splenic sequestration in a cohort of children with sickle cell anemia.

Objective: To analyze acute splenic sequestration (ASS) in children with sickle cell anemia diagnosed through a newborn screening program in the state of Minas Gerais, Brazil, and followed up at the hematology center in the city of Belo Horizonte, Minas Gerais, Brazil.

Methods: Retrospective cohort of 255 children with sickle cell anemia (Hb SS/Sbeta(0)) born between January 01, 2000, and December 31, 2004, and followed up until December 31, 2006. Data were abstracted from the patients' medical records.

Inhibitory effect of extracts of Brazilian marine algae on human T-cell lymphotropic virus type 1 (HTLV-1)-induced syncytium formation in vitro.

Extracts from four species of Brazilian marine algae collected from the Rio de Janeiro State coast were screened to determine the inhibitory effect on HTLV-1-induced syncytium formation. Before performing the syncytium inhibition assay the 50% cytotoxic dose (CyD50) of the algal extracts was evaluated. The antiviral test was carried out in HeLa cells co-cultured with HTLV-I infected T-cell line (C91/PL cells) in the presence of marine algal extracts in the concentration inferior to that corresponding to the CyD50.