The effect of topical tripeptide-copper complex on healing of ischemic open wounds

OBJECTIVE: To evaluate the effects of topical glycyl-L-histidyl-L-lysine tripeptide-copper complex (TCC; Iamin 2% Gel; Procyte Corporation, Redmond, WA) on healing in ischemic open wounds. STUDY DESIGN: Experimental study. SAMPLE POPULATION: Twenty-four adult male Sprague-Dawley rats. METHODS: Rats were divided into 3 groups: topical TCC, topical TCC vehicle (hydroxypropyl-methylcellulose), and no treatment (control). Six-mm-diameter, full-thickness wounds were created within an ischemic bipedicle skin flap on the dorsum of each rat. Each day, for 13 days, wound margins were traced, and the TCC and TCC vehicle groups were treated topically. Tracings were scanned, and wound perimeter and area were calculated. On days 6, 10, and 13, selected wounds were biopsied and analyzed for tumor necrosis factor alpha (TNF-alpha) and matrix metalloproteinases (MMP) 2 and 9. RESULTS: A significant decrease in wound area was seen in the TCC group, but not the vehicle group, when compared with the control group on days 3 to 5, 6 to 9, and 11 to 13 and when TCC was compared with TCC vehicle on days 3 and 9. On day 13, initial wound area had decreased by 64.5% in the TCC group, 45.6% in the vehicle group, and 28.2% in the control group. On days 6, 10, and 13, TCC-treated wounds contained significantly lower concentrations of TNF-alpha and MMP-2 and MMP-9 than control wounds. CONCLUSION: Topical TCC resulted in accelerated wound healing in ischemic open wounds. CLINICAL RELEVANCE: Topical TCC is an effective stimulant of healing of ischemic open wounds in rats and may have an application for the treatment of chronic wounds in other species. Clinical evaluation of topical TCC is warranted.     

SONOGRAPHIC AND SCINTIGRAPHIC EVALUATION OF ACUTE RENAL ALLOGRAFT REJECTION IN CATS

The sonographic features of acute renal allograft rejection in humans and dogs are manifested by increase in renal cross-sectional area and reduction in renal cortical blood flow. These changes have not been investigated in cats. The objectives of this study were to evaluate sonographic and scintigraphic changes during acute renal allograft rejection in cats. Eight SPF, intact, adult, male cats received heterotopic renal allotransplantations. Immunosuppressive doses of cyclosporine and prednisolone were administered for 14 days and then discontinued to allow acute allograft rejection to occur. Serial measurements of renal cross-sectional area, resistive index (RI), echogenicity, and glomerular filtration rate (GFR) were performed to evaluate changes during acute rejection. Upon sonographic confirmation of absent diastolic blood flow or a 20% increase in cross-sectional area of the allograft, a nephrectomy and histopathologic evaluation were performed. Acute allograft rejection was confirmed histologically in all cats. Significant increases in renal cross-sectional area (P < 0.001) occurred postoperatively and during rejection. There were no significant changes in RI (P = 0.43) at any time. A subjective increase in medullary echogenicity and a decrease in corticomedullary demarcation were observed in the rejection period. While GFR decreased significantly in the immediate postoperative period (P < 0.001), no further change occurred during rejection (P = 0.42). Changes in RI and GFR do not appear to be sensitive indicators of acute renal allograft rejection in cats. Serial measurements of renal cross-sectional area appear to be a sensitive method for the early diagnosis of allograft rejection in feline renal transplant recipients.     

Safety and feasibility of transesophageal pacing in a dog

This study investigated the feasibility of using a modified transesophageal atrial pacing system for dogs requiring temporary ventricular pacing. Atrial pacing was readily achieved in the one dog studied, but it caused considerable diaphragmatic movement. Ventricular pacing could not be achieved at any lead configuration or energy stimulation. While transesophageal cardiac pacing was a safe procedure, the large variation in the chest anatomy of dogs requires further study to explore this model as a substitute for transvenous or transthoracic ventricular pacing.