Trickle perfusion for organ preservation

An automated and portable low-flow pulsatile perfusion system for organ preservation

While machine preservation reduces the incidence of delayed graft function in renal transplant recipients, it is only used in 10% of kidney transplantations. The performance of our portable, low-flow-pulsatile organ perfusion system was examined in a canine kidney autotransplantation model. Grafts were stored for 72 h by simple cold preservation in University of Wisconsin (UW) solution, or by high or low-flow machine preservation After preservation, the grafts were autotransplanted and the animals were followed for 15 days. Graft function was better in machine-preserved kidneys. Tissue biochemistry indicated that machine preservation resulted in higher levels of adenine nucleotides and better histological integrity than the cold storage. While histology and biochemistry of machine-preserved groups were similar, electromicroscopy of high-flow grafts showed mild accumulation of intravenous debris and endothelial swelling. This study shows that a simplified machine perfusion technique is effective for organ preservation.

Nucleotide sequence of the large terminal repeat of two different strains of gibbon ape leukemia virus

Gibbon ape leukemia virus, SEATO strain (GaLV-SEATO), a virus that induces myeloid leukemia in gibbon apes, and GaLV, San Francisco strain (GaLV-SF), a virus associated etiologically with lymphocytic leukemia in gibbon apes, have been molecularly cloned. The complete nucleotide sequence of the large terminal repeats (LTRs) of both viruses are reported and compared to the previously published nucleotide sequence of the LTR of another member of the same virus group, the simian sarcoma virus (SSV). Substantial homology is evident among all three LTR sequences. The most striking feature of the GaLV-SEATO LTR is the presence of a 45-bp tandem direct repeat in the U3 region, an area likely to contain transcriptional enhancers. Both GaLV-SEATO and GaLV-SF contain a deletion in U3 when compared to SSV. Each of the three LTRs differ from the other two by short deletions in R-U5 and short additions in U3, as well as by numerous point mutations. The possibility that the structural changes observed in the LTR contribute to the differences in the pathogenic effects of these viruses is discussed.

[Canine kidney preservation by intermittent perfusion with hypothermic Collins- or Sacks-solution (author's transl)]

37 canine kidneys were intermittently perfused with Collins- or Sacks-solution every 2--6 h. 32 of these kidneys were transplanted after 12--24 h storage time. Additionally, 24 kidneys were stored under hypothermia for 12--24 h and then transplanted (control group). During perfusion the oxygen consumption of the kidneys and the enzyme and lactate release were measured. It was impossible to improve the results of hypothermic storage preservation by intermittent perfusion of the kidneys, on the contrary kidney function deteriorated by the number of perfusion processes. The failure of intermittent perfusion is caused by the increase of renal vascular resistance during perfusion. From the oxygen consumption and lactate release measurement it was concluded, that the washout solutions for kidney preservation should contain more substrate which can be utilized under anaerobic conditions to improve the results of hypothermic storage preservation.

Perfusion in the experimental preservation of the rat heart

Rat hearts have been preserved for 24 hours using four different preservation solutions. The results suggest that the best preservation fluid is Tyrode's solution with Ficoll 5 per cent. A comparison of simple cooling of the heart and perfusion, either continuous or intermittent, has shown that intermittent perfusion of the heart for 2 minutes every 6 hours gives the highest rate of 24-hour preservation.

Hypothermic asanguineous circulatory arrest in adult dogs

A new technique for the institution of hypothermic asanguineous circulatory arrest (HACA) is described and evaluated. It employs rapid cooling and hemodilution at high flow rates. Survival and protection of neurologic and other organ function were obtained using asanguineous circulatory arrest, and the method appears to be an improvement over circulatory arrest using conventional methods for cooling. The total duration of extracorporeal circulation is much shorter than with currently used methods of circulatory arrest. Applications of this technique in general and transplantation surgery as well as cardiac surgery are discussed.

Liver preservation by single passage hypothermic "squirt" perfusion

A single passage, hypothermic, intermittent squirt perfusion of the pig's liver is described which has allowed preservation of porcine livers for up to 17 hours. After preservation, orthotopically allografted livers can maintain recipient animals in good health. If this technique can be applied to clinical liver transplantation it should be possible to move livers from one hospital to another in the same way that kidneys are transported. This should increase the availability of donor livers for transplantation and avoid the serious disadvantages of moving the sick recipient just before the operation to the hospital where the donor has died.