Anatase titanium dioxide particles with a size of at most 100 nm wherein the particles are at least partially covered with a layer of at least one metal oxide, hydroxide or hydroxide oxide and the particles exhibit a BET specific surface of at least 70 m2g and a relative density of the order of 2. In one aspect, the siloxane compounds described herein can be used as Diels-Alder type curatives for bismaleimide or poly-maleimide monomers. Additionally, antiinflammatory drugs, such as steroids and NSAIDs can inhibit angiogenesis dependent diseases either alone or in combination with thalidomide and related compounds.