Publications by authors named "Todd A Ostomel"

Blood coagulates faster upon contact with polar glasslike surfaces than on nonpolar plastic surfaces; this phenomenon is commonly termed the glass effect. However, the variable hemostatic response that we report here for contact-activated coagulation by different metal oxides, all of which are polar substrates, requires a refinement of this simple polarity model of how inorganic metal oxides activate the intrinsic pathway of blood coagulation. To our knowledge, the role of metal oxide surface charge as determined at the physiological pH and Ca2+ concentration of blood has not been previously investigated.

View Article and Find Full Text PDF

Background: We have previously identified a granular zeolite hemostat (ZH) as an effective agent for control of severe bleeding, and it is currently being used by the US troops in the battlefield. ZH causes an exothermic reaction on application, which theoretically can be decreased by altering its chemical composition or changing its physical properties. However, the effect of these alterations on the hemostatic efficacy is unknown.

View Article and Find Full Text PDF

The tunable in vitro blood clotting activity of high-surface-area hemostatic bioactive glass is evaluated by Thromboelastograph, a clinical instrument for quantifying changes in blood during coagulation. The hemostatic trends associated with hemostatic bioactive glass and a new preparation of spherical hemostatic bioactive glass, along with similar Si- and Ca-containing oxides, are described and related to Si:Ca ratios, Ca2+ availability and coordination environment, porosity, DeltaHHydration, and surface area. Hemostatic bioactive glass is a new material with an excellent efficacy for inducing hemostasis and is chemically distinct from the traditional bioglass employed for bone growth.

View Article and Find Full Text PDF

Introduction: The United States military currently outfits our soldiers with a zeolite-based hemostatic agent (HA) that is applied directly onto a traumatic wound to induce hemostasis and prevent loss of life from exsanguination. The goals of this work were to identify and implement strategies to attenuate a tissue burning side effect associated with the HA, resulting from a large release of heat upon hydration, without adversely affecting the wound healing properties. Five ion exchanged derivatives of the parent HA were prepared and characterized with regard to their material and thermal properties, in vitro hemostatic efficacy, and antibacterial activity.

View Article and Find Full Text PDF

Free-standing 10 microm thick mesoporous titania films containing anatase nanocrystallites have been prepared and their structural evolution as a function of calcination temperature is reported.

View Article and Find Full Text PDF