Time of appearance and histology of tumors induced in the dorsal skin of C3Hf mice by ultraviolet radiation from a mercury arc lamp

The time course of skin tumor induction was determined in hair-clipped inbred agouti C3Hf mice irradiated three times per week with a medium-pressure quartz-mercury lamp; 4 different UV doses were used. Although the ears were also exposed to the radiation, in the 3 groups given the highest doses no ear tumors were observed by the time each animal had developed at least 1 tumor on its back. No tumors were found in the animals receiving the lowest UV dose. In the group receiving the highest dose, males developed tumors earlier than did females; this trend continued in the lower dose groups. Many tumors that developed in the back skin were well-differentiated squamous cell carcinomas. Others were less well-differentiated squamous cell carcinomas. Others were less well defined so that the cell of origin was difficult to determine. In the group receiving the highest UV dose, the squamous cell carcinomas were few, whereas at the lower doses they predominated.     

Antimicrobial activity of 12 broad-spectrum agents tested against 270 nosocomial blood stream infection isolates caused by non-enteric gram-negative bacilli: occurrence of resistance, molecular epidemiology, and screening for metallo-enzymes

From March 1989 to March 1993, six athletic patients were treated in our institution by thrombolytic therapy for acute effort axillary-subclavian vein thrombosis in thoracic outlet syndrome. Mean age of these patients was 20 (range 14 to 27). An in situ infusion with urokinase (2,500 U/kg/h) and Heparin (100 U/kg/12 hours) was given during 64 hours (Range 14 to 72). Phlebography showed a complete reperfusion in three cases (the treatment began within an average period of 5.6 days), partial reperfusion in two cases (the treatment began within an average period of 8.5 days). In one case there was no reperfusion on phlebography: treatment began within an average period of 15 days. For this patient, a venous axillo-jugular bypass graft was performed. In all cases, there was no bleeding complication. A trans-axillary first rib resection was done three months later. Mean follow up was 31 months (range: two to 51 months). All patients recovered their previous physical status. Echo-Doppler exam showed normal subclavian vein flow in four cases, partial occlusion in one case and a total occlusion of the subclavian vein flow in one case. In this last case, the thrombolytic therapy failed to restore the permeability of the subclavian vein. Bypassgraft was patent. Axillary-subclavian vein thrombosis seen within a period of seven days should be treated by local thrombolytic therapy using urokinase and heparin.     

Global phylogeography of the ridley sea turtles (Lepidochelys spp.) as inferred from mitochondrial DNA sequences

BACKGROUND: The cardiovascular applications of magnetic resonance (MR) techniques in coronary artery disease have increased considerably in recent years. Technical advantages of MR imaging are the excellent spatial resolution, the characterization of myocardial tissue, and the potential for three-dimensional imaging. These characteristics allow the accurate assessment of left ventricular mass and volume, the differentiation of infarcted from normal tissue, and the determination of systolic wall thickening and regional wall motion abnormalities. METHODS: In addition to the conventionally used spin-echo and cine-echo techniques, newer techniques such as myocardial tagging, ultrafast MR imaging and MR coronary angiography have been developed. These newer techniques allow a more accurate assessment of ventricular function (tagging), myocardial perfusion (ultrafast imaging), and evaluation of stenosis severity (MR coronary angiography). Particularly early detection and flow assessment of stenosed coronary arteries and bypasses by MR angiography would constitute a major breakthrough in cardiovascular MR imaging. Apart from the MR imaging techniques, cardiac metabolism may be well assessed using MR spectroscopy. This provides unique information on the metabolic behaviour of the myocardium under conditions stress-induced ischemia. However, the definite niche of cardiac MR spectroscopy has still to be settled. CONCLUSION: Currently, MR techniques allow the evaluation of anatomy and function (accepted use), perfusion and viability (development phase), and coronary angiography (experimental phase). A particular strength of MR imaging is that one single MR test may encompass cardiac anatomy, perfusion, function, metabolism and coronary angiography. The replacement of multiple diagnostic tests with one MR test may have major effects on cardiovascular healthcare economics and would outweight the cost inherent to the MR angiography procedure.     

British Inflammation Research Association meeting: metalloproteinases and inflammatory diseases, the Fielder Centre, Hatfield, UK, 18 April 1997

Nitric oxide released by macrophages during inflammation reacts with active oxygen to form peroxynitrite. Peroxynitrite nitrates protein and peroxidizes lipids. gamma-Tocopherol traps peroxynitrite and is more effective than alpha-tocopherol in protecting lipids against such peroxidation.