Mitigation of experimental, chronic post-thoracotomy pain by preoperative infiltration of local slow-release bupivacaine microspheres.

Background: Postoperative pain is treated incompletely and ineffectively in many circumstances, and chronic postoperative pain causes suffering and diminishes productivity. The objective of this project is to determine whether a recently developed slow-release formulation of bupivacaine was effective in reducing the experimental chronic postoperative pain.

Methods: In male Sprague-Dawley rats (250-300 g body weight), bupivacaine-releasing microspheres (MS-Bupi), containing 60 mg of bupivacaine base, were locally injected (MS-Bupi-L) 2 hours preoperatively into the subcutaneous compartment at the locus for experimental thoracotomy.

Local pathology and systemic serum bupivacaine after subcutaneous delivery of slow-releasing bupivacaine microspheres.

Background: Prolonged local anesthesia, particularly desirable to minimize acute and chronic postoperative pain, has been provided by microspheres that slowly release bupivacaine (MS-Bup). In this study, we report on the systemic drug concentrations and the local dermatopathology that occur after subcutaneous injection of MS-Bup.

Methods: Rats (approximately 300 g) were injected under the dorsolumbar skin with MS-Bup containing 40 mg of bupivacaine (base) or with 0.

Prolonged amelioration of experimental postoperative pain by bupivacaine released from microsphere-coated hernia mesh.

Background And Objectives: Postoperative pain alters physiological functions and delays discharge. Perioperative local anesthetics are effective analgesics in the immediate 1- to 2-day postoperative period, but acute pain often lasts longer. The goal of this work was to develop a local anesthetic formulation adhering to an intraoperative implanted device that reduces pain for at least 3 days after surgery.

Inhibition by local bupivacaine-releasing microspheres of acute postoperative pain from hairy skin incision.

Background: Acute postoperative pain causes physiological deficits and slows recovery. Reduction of such pain by local anesthetics that are delivered for several days postoperatively is a desirable clinical objective, which is approached by a new formulation and applied in animal studies reported here.

Methods: We subcutaneously injected a new formulation of poly-lactic-co-glycolic acid polymer microspheres, which provides steady drug release for 96+ hours into rats at the dorsal region 2 hours before surgery.

Prolonged nerve block by microencapsulated bupivacaine prevents acute postoperative pain in rats.

Background And Objectives: To minimize acute postoperative pain, a new formulation of slowly released bupivacaine was developed.

Methods: Bupivacaine was microencapsulated at 60% (wt/wt) in poly-lactide-co-glycolide polymers and characterized for physicochemical properties and bupivacaine release kinetics. This formulation was injected around the rat sciatic nerve to produce an antinociceptive effect to toe pinch.

Mitigation of ectopic calcification in osteopontin-deficient mice by exogenous osteopontin.

Ectopic calcification is a major cause of bioprosthetic heart valve failure. New therapeutic opportunities are offered by the growing understanding that ectopic calcification is an actively regulated process involving several key gene products. One of these products, osteopontin (OPN), is a glycosylated phosphoprotein previously shown to inhibit apatite crystal formation, induce carbonic anhydrase II, and promote mineral resorption.

Triglycidylamine crosslinking of porcine aortic valve cusps or bovine pericardium results in improved biocompatibility, biomechanics, and calcification resistance: chemical and biological mechanisms.

We investigated a novel polyepoxide crosslinker that was hypothesized to confer both material stabilization and calcification resistance when used to prepare bioprosthetic heart valves. Triglycidylamine (TGA) was synthesized via reacting epichlorhydrin and NH(3). TGA was used to crosslink porcine aortic cusps, bovine pericardium, and type I collagen.

Hyaluronic acid grafting mitigates calcification of glutaraldehyde-fixed bovine pericardium.

Pathologic calcification is the leading cause of the clinical failure of glutaraldehyde-fixed bovine pericardium used in bioprosthetic valves. A novel surface modification of glutaraldehyde fixed bovine pericardium was carried out with high molecular weight hyaluronic acid (HA). HA was chemically modified with adipic dihydrazide (ADH) to introduce hydrazide functional groups onto the HA backbone.