In situ saphenous vein bypass grafting - still first line treatment? A prospective study comparing surgical results between diabetic and non-diabetic populations.

BACKGROUND: This prospective study compares results of infrainguinal revascularisation with autologous vein in diabetic and non-diabetic populations. PATIENTS AND METHODS: 101 patients (diabetics (A) n = 50 and non-diabetics (B) n = 51) were operated upon with an in situ saphenous vein bypass to the popliteal artery below knee or to crural arteries, due to critical ischemia. Data on operative details, morbidity, mortality, secondary interventions and graft patency, were collected prospectively. All patients were followed up for 5 years. RESULTS: The two groups were similar except that diabetics more often suffered from gangrene or tissue loss. The distal anastomoses were constructed significantly more distally in diabetics. There were no differences in perioperative bleeding, length of operation, hospital stay or 30 d mortality. The 5 year patency did not differ significantly between groups, A 68 % vs. B 72 %. The limb salvage was equal in both groups, 86 % after 5 years. Mortality during follow up was significantly higher among diabetics, at two years A 31 % vs. B 14 %. CONCLUSIONS: Distal revascularisation with in situ technique is a durable procedure that can be performed with very good results in both diabetics and non-diabetics. The survival among diabetics is however significantly lower, although reaching 69 % at two years.

Magnetic cues trigger extensive refuelling.

Long stretches of sea and desert often interrupt the migration routes of small songbirds, whose fat reserves must be restored before these can be crossed as they provide no opportunity for refuelling. To investigate whether magnetic cues might enable inexperienced migratory birds to recognize a region where they need to replenish their body fat, we caught and held thrush nightingales (Luscinia luscinia) in Sweden just before their first migration and exposed them to a magnetic field simulating that at a migratory stopover in northern Egypt, before the Sahara Desert. We found that this magnetic field stimulated the birds to extend their fat-deposition period, indicating that magnetic cues may help small migratory birds to confront large ecological barriers.

A feeding experiment on migratory fuelling in whitethroats, Sylvia communis

The influence of food abundance on whitethroats' behaviour when preparing for autumn migration was investigated in a feeding experiment on the island of Gotland in the Baltic. Whitethroats attracted to a feeding site during post-juvenile moult attained a stable body mass 1.4 g higher than birds in natural conditions. This fuel load is well below the maximum that whitethroats could deposit. After maintaining stable body mass during moult, the whitethroats started to gain mass and thereafter soon departed on migration. This shift was due to the birds increasing their gross food intake by about 70%. Both the average rate of fuel deposition (about 7% of lean body mass per day) and the average departure fuel load (over 50% of lean body mass) were much higher for birds at the feeding site than for birds in natural conditions. No correlation between rate of fuel deposition and departure fuel load was found at the feeding place. Larger departure fuel loads in late individuals suggest that departure decisions are affected by temporal cues. Comparisons with models of time-minimization during migration show that the lack of correlation between rate of fuel load and departure load contradicts the predictions in one model. In another model, where a finite distance is included, the relationship between rate of fuel deposition and departure fuel load is predicted to be step-wise. This means that within certain ranges of rate of fuel deposition the departure fuel load should not change, which is consistent with the result found in this study. Copyright 1998 The Association for the Study of Animal Behaviour.