Preservation damage in liver transplantation. Influence of rapid cooling

Liver preservation and transplantation was performed in pigs. For flush perfusion cold (2 degrees C) and warm (15 degrees C) lactated Ringer's solution were compared. Administration of cold Ringer's resulted in a severe endothelial damage of sinusoids that was aggravated after recirculation, as shown by electron microscopic examination. Using warm Ringer's solution this alteration was limited. Liver parenchymal cells are impaired mainly during reflow as a consequence of microcirculatory disturbance. After cold flushing animals died within a few hours, whereas after flushing with warm Ringer's solution pigs survived definitively.

[Current status of liver transplantation]

The importance of the liver transplantation for the treatment of infaust liver diseases is nowadays regarded as undisputed. The results could be improved during the last years: on an average 40% of the patients still live one year after the transplantation. The control of the transplant rejection and the diminution of the ischaemic liver damage are preeminent pathophysiological problems. Clinical routine and experience essentially further the optimization of the results.

Alteration of the ultrastructure of the pig liver after a continuous perfusion of six hours in vitro

Livers of mini LEWE pigs were perfused continuously for 6 h on a novel perfusion system through the portal vein (laminar flow from 200 to 300 ml/min, pressure 270 Pa) and through the A. hepatica (pulsating flow from 100 to 200 ml/min, pressure: 10.6/5.5 kPa). The following perfusion media were used for determining the best conservation conditions at 10 to 12 degrees C: Pig blood/Krebs-Henseleit bicarbonate buffer 1:1; Pig blood/Ringer lactate solution 1:1; Pig plasma; Collins C 2 perfusion solution. After perfusion with Collins C 2 solution the hepatocytes show swelling and dilation of the granular endoplasmic reticulum; after perfusion with the other solutions the changes of the hepatocytes are negligible. The alterations of the sinusoidal wall cells depend on the perfusion pressure and flow and the composition of the solution. After continuous perfusion the sinusoidal walls are characterized by vesicles of endothelial cells, dilatation of the Disse space and fragmentation of hepatic microvilli.

[Value of histopathologic findings following liver transplantation based on biopsy course studies]

A total of forty-four biopsies from nine liver transplantation patients, who had developed complications postoperatively, were studied histologically and, in part, electron-microscopically. Morphologic signs of acute rejection were seen in three patients, while there were indications of chronic rejection in one patient. In combined lesions, such as drug-induced hepatosis, cholangitis, hepatitis, and rejections, the interpretation of biopsy findings may be difficult, and special entities cannot in every case be separated unequivocally. Changes of serum bilirubin and of serum enzyme activity do not run entirely parallel to the microscopically detectable structural lesions. For diagnosis of complications after liver transplantation both the morphologic and the clinical findings must be considered.

Adenine nucleotides and glycolysis during liver preservation by simple hypothermic storage

Adenine nucleotides and glycolytic metabolites were examined during hypothermic storage of porcine livers by different preservation methods. The parameters ATP, ADP, AMP, G6P, F6P, FDP, GAP, 2PG, PEP, Pyr and Lact were investigated. The results indicate a dependence of adenine nucleotides but no dependence of glycolytic metabolites on preservation method. Storage by plasma protein fraction or Collins C2 solution causes a better result in TAN concentration after 6 h than albumin and Ringer storage or Ringer trickle perfusion. Conditioning the organ for a better outcome of preservation aimed at increasing the glycolytic rate is of questionable value.

[A method for determining the hemodynamic behavior of the liver in vitro]

Hemodynamic parameters of livers--especially resistance of the sinusoids and of functional portosystemic shunts--are investigated using an electro-physical model. During liver perfusion the inflow conduit is compressed irregularly. The dynamic changes of pressure and flow allow a calculation of the volume passing the sinusoids and the functional shunts.

[Electron microscopic findings during hypothermic storage preservation of the liver. II. (author's transl)]

Porcine livers were preserved by simple hypothermic storage for 6 h using plasma-protein-fraction 5%, albumin 5%, Collins C2, and Ringer-lactate followed by a morphometric evaluation of the electron-microscopic changes. The morphometric parameters reflecting swelling of mitochondriae showed the most pronounced changes and were suited best for reproduction. The best result was achieved by using Collins C2-storage. The endoplasmic reticulum was found to be only slightly swollen in all preservation solutions investigated here, at the same time a degranulation of granular endoplasmic reticulum could be demonstrated. The increase in volume of lysosomes per unit-volume was not significant.

[Electron microscopic findings during hypothermic storage. Preservation of the liver. I. (author's transl)]

Porcine livers were preserved by simple hypothermic storage for 6 h using plasma-protein-fraction 5%, albumin 5%, Collins C2, and Ringer-lactate. Electron-microscopic alterations primarily consist of aggregations of nuclear chromatin, marginal chromatin condensation, swelling and destruction of cristae mitochondriales, swelling and degranulation of the endoplasmic reticulum. These signs of cell damage are of varying intensity depending on the different preservation methods. The best condition of hepatocytes on the whole is guaranteed by using Collins C2-solution.

[Glycolysis during hypothermic storage preservation of the liver]

Porcine livers were preserved for 6 hours by simple hypothermic storage using plasma-protein-fraction, albumin, Collins C2, Ringer solution, and Ring-trickle-perfusion. Following glycolytic metabolites were examined: G6P, F6P, FDP, GAP, 2PG, PEP, pyruvate, and lactate. An alteration of glycolytic metabolite-profile by the different preservation methods was not seen. There is a limitation of glycolysis by the pyruvate-kinase-reaction. Glycolysis decreases depending from preservation time. An artificial increasing of glycogen or rate of glycolysis before hepatectomy seems to be without any effect.

[Immunoglobulins after experimental liver transplantation in pig]

During a period of 14 days after porcine liver transplantation immunoglobulins IgA, IgG, and IgM were investigated. IgA and IgG were slightly elevated at the end of investigation. The increase in IgM was higher and significant. This rise in immunoglobulin-level is thought to be a result of immunisation by parenchymatous insults after liver transplantation.

Structure of the Abelson murine leukemia virus genome

Virions produced from cells transformed by A-MuLV contain a 30S, 5.6 kb RNA that can be translated in a cell-free system to form the characteristic A-MuLV protein. This RNA was mapped by heteroduplex methods using DNA probes from M-MuLV, the presumed parent of A-MuLV. The overall organization of the RNA was determined by using full-length M-MuLV reverse transcribed DNA and visualizing the heteroduplexes in the electron microscope. This showed that A-MuLV and M-MuLV have homologous sequences at both ends of their RNAs but that the central portion of the A-MuLV genome is not homologous to sequences in M-MuLV RNA. A precise measure of the lengths of the shared regions was obtained by using S1 nuclease to digest hybrids between 32P-labeled M-MuLV DNA and A-MuLV RNA; the resulting fragments were analyzed for their length by electrophoresis. The regions of homology were shown to be 1320 nucleotides long at the 5' end and 730 nucleotides long at the 3' end. Thus approximately 6200 nucleotides of the approximately 8300 in M-MuLV RNA were deleted when the A-MuLV genome was formed, but an insert of 3600 nucleotides, presumably derived from the normal murine genome, was inserted in place of the deleted region.

[Prosthetic aspects in endosseous implantation]

Since 1975, 12 intra-osseous titanium blade implants have been applied to patients with unilateral or bilateral edentulousness of the terminal region of the mandible or with combined mandibular edentulousness. After taking impressions by means of individually fabricated transmitting copings and medium-flow silicone impression compounds, the temporary plastics bridges and the definite telescope bridge prostheses were made of precious metal alloys, using the "Biokop-Orthomat". Essential prerequisites for optimal functional performance of the implant bridge constructions are: creation of optimal occlusal conditions, tangential blocking of the remaining teeth by splinting one implant abutment with at least two natural teeth, and gingiva-free modelling of the telescope and crown margins at the implant abutment.