Myocutaneous flap failure: early detection with Gd-DTPA-enhanced MR imaging

Magnetic resonance (MR) imaging was used to evaluate myocutaneous flap viability in an animal model. Bilateral myocutaneous panniculus carnosus groin flaps were created in 14 piglets. Eight of the piglets underwent early occlusion of the vascular pedicle to one flap that resulted in flap failure in all cases. Six piglets underwent late occlusion of the vascular pedicle to one flap that resulted in flap survival in all cases. Spin-echo T1- and T2-weighted MR images were obtained from all piglets 2 and 24 hours after occlusion. Additional gadolinium diethylene-triaminepentaacetic acid (DTPA)-enhanced serial T1-weighted images were obtained in four piglets who underwent early occlusion and in four piglets who underwent late occlusion of the pedicle. The T2-weighted images showed increased signal intensity in both occluded and control flaps and thus did not help predict flap viability. Gd-DTPA-enhanced images enabled accurate prediction of flap viability. The images of early-occluded (non-viable) flaps demonstrated no contrast material enhancement, while both the late-occluded (viable) flaps and the control flaps were contrast enhanced. The authors conclude that Gd-DTPA-enhanced MR imaging can help predict myocutaneous flap viability in piglets.     

Urinary enzyme output during detoxification of chronic alcoholic patients

The urinary excretion of N-acetylglucosaminidase, gamma-glutamyl transferase and lactate dehydrogenase was elevated by two to three fold in chronic alcoholic patients when compared to normal controls. After 4 weeks of alcohol abstention, the urinary excretion of these enzymes returned to control values. Increased urinary enzyme excretion was not related to malnutrition or pathological glomerular filtration and is due most probably to a direct effect of alcohol on the renal proximal tubule.     

Vitrectomy and fluid/silicone-oil exchange for giant retinal tears: 5 years follow-up

A series of 64 eyes, in 64 patients with giant retinal tears, treated by vitrectomy and fluid/silicone-oil exchange, has been reviewed after 5 years. Anatomical success was achieved in 73% of cases and visual function in successful cases ranged from 6/6 to NPL; 66% achieved acuities of 6/60 or better and 32% had vision of 6/18 or better. These results compare favourably with those in a previous series reported after 6 months and 18 months. Epiretinal membrane proliferation and shortening accounted for the majority of retinal redetachments while macular abnormalities, especially pucker, were responsible for a poor visual outcome. Glaucoma is the most serious long-term complication of the surgical method and occurs most frequently in aphakic eyes. Retention of the crystalline lens, whenever possible, the creation of a 6 o'clock iridectomy in aphakic eyes, early removal of silicone oil and a conservative approach to the use of scleral buckles are recommended.Presented at the XVIth Meeting of the Club Jules Gonin, Bruges, 4–8 September 1988     

Effect of morphine and nalmefene on energy balance in diabetic and non-diabetic rats

Male rats made diabetic by intravenous injection of streptozotocin were used to evaluate the effect of the diabetic state on morphine- and nalmefene-induced changes in food intake and body weight. Morphine increased 4 hour food intake in non-diabetic rats after an initial injection, but increased intake in diabetic rats only after repeated injections. Unlike short term measurements, morphine decreased food intake when measured over 24 or more hours in both groups. Chronic injection of morphine decreased body weight only in non-diabetic rats. Feed efficiency data suggest that morphine had a more potent effect on energy balance in the non-diabetic rats. The opioid antagonist, nalmefene, did not alter body weight in either group and only altered food intake in the diabetic animals. These data are in concert with other reports indicating that the diabetic state renders animals less responsive to the effects of morphine on nociception and smooth muscle contraction.     

Central administration of the opioid antagonist, LY255582, decreases short- and long-term food intake in rats.

A variety of opioid antagonists have been reported to decrease short-term food intake, but few appear to reduce long-term intake. In the present study we evaluated the effect of a relatively new class of opioid antagonists, 3,4-dimethyl-4-phenylpiperidines, on short-term and long-term food intake after central administration. We also evaluated their affinities for the mu and kappa opioid receptor sites in synaptosomal membranes derived from rat whole brain tissue (minus cerebellum) and guinea-pig cortex, respectively. The affinities for the mu receptor sites were LY255582 greater than LY217273 greater than LY256897 greater than naloxone greater than LY227444. The affinities for the kappa receptor sites were LY255582 greater than LY256897 = LY217273 greater than LY227444. LY255582 reduced food intake for up to 24 h after a single intraventricular injection. Doses as low as 1 microgram of LY255582 decreased food intake for up to 4 h. All other drugs were much less powerful. Naloxone and LY256897 only decreased food intake after injection of the 100 microgram dose. LY227444 and LY217273 failed to decrease intake at all doses tested. LY255582 (100 micrograms) decreased food intake over a 7 day period when injected intraventricularly once per day. The body weight of the rats also decreased during the 7 day period. Upon cessation of drug administration body weights and food intake approached control levels. Thus, LY255582 appears to be a very potent and long-acting anorectic agent which may be useful in the treatment of obesity. The mu and kappa binding profile of the phenylpiperidines does not seem to clearly correlate with their anorectic activity.