Modeling of the petawatt PETAL laser chain using Miró code.

Miró software has been used intensively to simulate the Laser Megajoule (LMJ) with the treatment of amplification, frequency conversion, and both temporal/spatial smoothing of the beam for nanosecond pulses. We show that the software is able to model most relevant aspects of the petawatt PETAL laser chain in the subpicosecond regime, from the front-end to the focal spot with a broadband treatment of the amplification and compression stages, including chromatism compensation in the laser chain, segmentation and recombination of the beams on the second compression stage, and focusing by an off-axis parabola.

Different cytotoxicity and metabolism of doxorubicin, daunorubicin, epirubicin, esorubicin and idarubicin in cultured human and rat hepatocytes.

Both cytotoxicity and metabolism of five anthracyclines, namely doxorubicin, daunorubicin, epirubicin, esorubicin and idarubicin, were investigated in primary cultures of both rat and human adult hepatocytes and, for comparison, in a rat liver epithelial cell line. Toxicity was assessed by morphological examination and measurement of lactate dehydrogenase leakage after 24 hr of treatment. The rank order of toxicity for both rat and human hepatocytes was esorubicin greater than doxorubicin = epirubicin greater than or equal to idarubicin greater than daunorubicin, and for rat epithelial cells: esorubicin greater than or equal to epirubicin greater than idarubicin = daunorubicin = doxorubicin. Human cells were around 2-fold less sensitive than rat hepatocytes to all anthracyclines. Anthracyclines and their metabolites were analyzed by HPLC. Differences in both the percentages and routes of metabolism were demonstrated between rat and human hepatocytes. The main metabolite was the 13-dihydro-derivative (-ol derivative) in both species from daunorubicin, idarubicin and esorubicin. Glucuronides of epirubicin and epirubicinol were found only in human hepatocytes. In addition, several unidentified metabolites were detected of esorubicin, idarubicin and daunorubicin in rat hepatocytes. In human hepatocytes, only one unknown metabolite from daunorubicin and doxorubicin was found to be formed by cells from a different donor. In spite of variations between individuals, human hepatocytes generally metabolized anthracyclines more actively than did rat hepatocytes. Rat liver epithelial cells were only able to convert daunorubicin and idarubicin, the two molecules which have the best affinity for the non-specific NADPH-dependent aldoketoreductase system. Three compounds (doxorubicin, epirubicin and esorubicin) were present in large amounts in the cells as the parent drug, another (idarubicin) as the 13-dihydro-derivative. This comparative study on cytotoxicity and metabolism of five anthracyclines in rat and human hepatocyte cultures emphasises species differences and the importance of this in vitro model system for further analysis of the metabolism and effect of anthracyclines.

Constrictive perivenous mesh prosthesis for preservation of vein integrity. Experimental results and application for coronary bypass grafting.

Saphenous veins undergo dramatic morphologic changes when used as coronary bypass grafts, and careful preparation of the graft alone is inadequate in preventing these changes. In this study, the use of a constrictive mesh for vein graft was evaluated. Fourteen sheep were subjected to a 5 cm resection of the carotid artery. Six sheep (Group A) received a jugular vein interposition graft, and the other eight sheep (Group B) received a jugular vein graft on which the constrictive mesh had been applied. The diameter of grafts in Group A was 14 +/- 1 mm compared with 7 +/- 0.5 mm for Group B (p = 0.05). The animals were put to death 4 months later. Scanning electron microscopy showed a disruption of the endothelial lining in Group A and a normal endothelium in Group B. Microscopy showed a statistical difference between Groups A and B regarding regularity and thickness of the intimal hyperplasia. Group B showed a moderate and regular intimal thickening and increased vasa vasorum. This indicates that distention and subsequent damage of the vein graft may be minimized by use of a constrictive mesh. Saphenous grafts surrounded by this constrictive mesh were inserted in four patients. Vein diameters were, respectively, 5, 4.3, 3.5, and 3.5 mm before meshing. After insertion in the mesh, vein diameters were 4.3, 3.5, 2.8, and 2.5 mm, respectively. Angiography performed 2 months later showed patent grafts of regular caliber.

Renal failure in the course of reactivation of varicella-zoster virus infection in a renal transplant recipient.

Renal failure developed in a 20-year-old female renal transplant recipient in the course of reactivation of varicella-zoster virus infection. The patient was treated with acyclovir and immunosuppression was continued. The year later renal function in the transplanted kidney was satisfactory.