L Hyacinthe | PubMed Health

PubMed1993

Patch graft urethroplasty using dye enhanced laser tissue welding with a human protein solder: a preclinical canine model.

We investigated the use of the KTP-532 laser to perform a patch graft urethroplasty in 24 adult male dogs using the inner preputial skin as the donor site. In group 1 (12 dogs) repairs were completed with conventional microsuturing techniques, while in group 2 (12 dogs) they were completed using the KTP-532 laser. In the laser welding group the addition of a protein solder (40% human albumin) doped with fluorescein was used. Assessment parameters included a preoperative and postoperative retrograde urethrogram, measurement of intraluminal bursting pressure in the first 6 animals in each group, operative time and histology. Operative time was 42% faster and acute intraluminal bursting pressures were significantly higher in the laser-solder group. No fistulas occurred in the laser-solder group compared to a 50% fistula rate in the suture group. Significant radiographic abnormalities were seen in the urethras of the suture repair group.

Albumins↗

PubMed1992

Mediatory role of copper in reactive oxygen intermediate-induced cardiac injury.

In this report the mediatory role of copper in cardiac injury produced by reactive oxygen intermediates was examined. Isolated rat hearts were perfused with Krebs-Henseleit buffer containing 0.25 mM ascorbate plus varying concentrations of copper-bis-histidial for up to 60 min. Using salicylate as a probe, OH generation by this system was demonstrated. Copper or ascorbate alone had minimal effect on cardiac function as determined by heart rate, coronary flow, left ventricular systolic pressure development, end diastolic pressure and +/- dP/dtmax. Copper, from 0.5 microM to 20 microM, and ascorbate, 0.25 mM, resulted in concentration-dependent decreases in all of the experimental variables. Treatment with 5 or 20 microM copper resulted in complete loss of cardiac function within 40 and 30 min, respectively. By 30 min, 5 microM copper had resulted in increased end diastolic pressure to greater than 40 mmHg. By 60 min, perfusion with 1 microM copper resulted in almost 100% loss of function and end diastolic pressure greater than 25 mmHg. Copper, 0.5 microM, also decreased cardiac function, but to a lesser degree. Catalase, 100 units/ml, was effective in preventing the copper-ascorbate induced cardiac damage while superoxide dismutase, 25 units/ml, was ineffective. Observations by light and electron microscopy demonstrated patchy regions with vacuolization corresponding to swollen mitochondria. These results clearly demonstrate that copper-catalyzed redox reactions can induce cardiac injury via a mechanism which appears to be related to the production of OH.

Animals↗

PubMed1992

Percutaneous gastrostomy made simple.

The use of percutaneous endoscopic gastrostomy has obviated the necessity of laparotomy for enteral access. The authors propose a new technique for introduction of the gastrostomy tube. It entails use of the laparoscopic trocar to gain entrance into the gastric lumen.

Female↗