Quantification of lipids, liposomes, amino acids, and proteins by thermal ultramicrodigestion and an ultramicrocoulometric assay, based on the reaction of hypobromite with ammonia.

The quantification of nitrogen in organic material is described. It is based on a novel thermal ultramicrodigestion in combination with an ultramicrocoulometric quantification. The lower detection limit of the coulometric measurement is 0.5 microg nitrogen, which corresponds to 20 microg lipid, 3 microg glycine, or 4 microg protein. Therefore it is as sensitive as the frequently used Lowry method. In contrast to the Lowry protein determination it is not disturbed by detergents and most other interfering substances.

Technique and results of regional hyperthermic cytostatic arm perfusion for malignant melanoma.

Isolated hyperthermic cytostatic limb perfusion has been established as an efficient procedure for the treatment of malignant melanoma of the limbs. However, perfusions of the upper extremities are generally carried out much less frequently than would be expected given the distribution pattern of malignant melanoma and sarcoma. Thus, isolated descriptions of treatment results for perfusion of the upper extremities are not available. Between 1991 and 1994, arm perfusions using melphalan 1.0 mg/kg body weight were given to 14 patients with malignant melanoma, using the standardized method of perfusion described herein. Within an average observation period of 34.9 months (range, 12-65 months), 11 (78.7%) of the 14 patients who had M.D. Anderson stage II-IV melanoma remained free of local recurrence. In fact, 10 (71.6%) of the patients were still alive at the end of the observation period. None of the 14 patients showed any systemic adverse effects, although 1 patient developed a lymphedema 32 months after perfusion and 2 patients showed a postoperative temporary neurologic deficit. These results demonstrate that isolated perfusion of the upper limb with heat and melphalan under standardized conditions remains the treatment of choice for melanoma of the arm, as for melanoma of the leg, without a higher rate of complications.

[Thirty years of hemodialysis treatment at Martin Luther University in Halle-Wittenberg]. / Dreissig Jahre Hämodialysebehandlung an der Martin-Luther-Universität Halle-Wittenberg.

An artificial kidney has been taken into operation in the clinic for surgery of the University of Halle-Wittenberg since 1959. This was the second clinical arrangement in the DDR. The indication of the application evolved by the acute renal failure, about the chronic renal insufficiency, within to the hemodialysis as an additive for kidney transplantation. Coworkers of our clinic were engaged vigorously in the technical development of this method in the GDR.

[Effect of the stable prostacyclin analog Iloprost on enzyme release during extracorporeal kidney perfusion]. / Die Wirkung des stabilen Prostazyklin-Analogons Iloprost auf die Enzymfreisetzung während der extrakorporalen Nierenperfusion.

The influence of the stable prostacyclin-analogue Iloprost (Fa. Schering, Berlin) in the enzyme release from extracorporalic perfused kidneys was tested in an experimental investigation. The mechanic hypothermic perfusion was carried out on four different conditions. The estimation of specially cytosolic, lysosomal, and membrane-associated enzymes in the perfusat of the kidneys showed less activities in the Iloprost-protected kidneys. The results after the replantation of the kidneys support the interpretation of the enzyme determinations.

[The improvement of the tolerance of the kidney for ischemia with the prostacyclin analog iloprost]. / Untersuchungen zur Verbesserung der Ischämietoleranz der Niere mit dem Prostazyklinanalogen Iloprost.

Operative trauma, ischemia, release of catecholamines and thermal stimuli in consequence of harvesting, preservation and transplantation deteriorate the renal capillary circulation. By crossing of tolerance limits arises an irreversible transplant damage. The conditions of our examinations were placed in this field. By pre- and postischemic application of Iloprost was demonstrable an improvement of the ischemic tolerance of the kidney. Correction of renal hemodynamics, antiplatelet action and cytoprotection are the reasons of the protective influence of Iloprost in our opinion.

[Effect of Iloprost (ZK 36 374) on hemodynamic parameters during kidney donor conditioning in animal experiments]. / Der Einfluk von Iloprost (ZK 36 374) auf hämodynamische Parameter während der Nierenspenderkonditionierung im Tierexperiment.

Hemodynamic parameters during the conditioning of kidney donors were tested under the influence of Iloprost (ZK 36 374), a stable prostacyclin derivate, in 12 house swine of a body weight of 20-50 kg. The electromagnetically measured blood flow in the right renal artery increased on an average of 73.2% after intraaortic infusion of Iloprost (1 micrograms/kg.min) during 15 minutes. The mean arterial blood pressure decreased simultaneously by 14.7%. The renal flow resistance (RVR), by blood pressure and blood flow calculated, decreased by 49.7% in average. Iloprost appears well-suitable for conditioning donors, it shows advantages in contrast to the hitherto used drugs.

[Effect of iloprost on aggregation behavior in kidney conditioning and changes in iloprost concentration in kidney preservation]. / Der Einfluss von Iloprost auf das Aggregationsverhalten während der Nierenkonditionierung und Iloprostkonzentrationsveränderungen bei der Nierenkonservierung.

The conditioning of the donor by 1.0 microgram/kg X min Iloprost over 15 minutes leads to a considerable inhibition of the aggregation of thrombocytes in the domestic pig. 160% more ADP had to be added than before the application of Iloprost. When 0.5 microgram/ml Iloprost are added to the perfusion fluid and to the reperfusion fluid 0.22 microgram/ml and 0.27 microgram/ml, respectively, are to be proved in the venous efflux. Whether or not the difference is absorbed or metabolized must remain open. During the 72-hour storage of the kidney in a Euro-Collins-solution with 0.5 microgram/ml Iloprost after 24 hours a decrease of 0.34 microgram/ml, after 48 hours to 0.33 microgram/ml and after 72 hours to 0.20 microgram/ml takes place. Thus Iloprost is present in an effective concentration also after 72 hours. The decrease to one plateau rather speaks for a consumption by active metabolic effect or absorption than for a chemical decomposition.

[Hemodynamic studies of iloprost-conditioned ischemically stressed kidneys in animal experiments]. / Hämodynamische Untersuchungen an Iloprost-konditionierten ischämisch belasteten Nieren im Tierexperiment.

By means of computer-assisted Doppler signal analysis on the exposed renal artery of the pig the change of the haemodynamics under the influence of Iloprost is investigated in comparison to the electromagnetic flow measurement. The Doppler sonographic establishment of the speed of the blood flow and the relative volume of the blood flow allows additional informations about characteristic changes of the form of the pulse. During the measurement in situ on the renal artery the result was during the intraarterial application of Iloprost a distinct increase of the renal blood flow with simultaneous decrease of the renal resistance, which, issuing from the Doppler signal analysis, is characterized as change of the renal resistance index. The kidneys conditioned under influence of Iloprost were retransplanted after a warm ischaemia-time of 45 minutes with following machine preservation of 24 hours and showed a stable flow characteristics for the whole investigation period. The Doppler signals directly conducted via the renal parenchyma showed a stable pulsation also in the smaller arterial vessels.

Improvement in the preservation of ischemically impaired renal transplants of pigs by iloprost (ZK 36 374).

Kidneys of five pigs were preoperatively perfused with iloprost in situ (infusion of 0.5 microgram X kg-1 for 15 minutes) and exposed to a warm ischemic period of 45 minutes. The behaviour of these kidneys during initial perfusion by gravity and hypothermic mechanical perfusion for 24 hours was comparable to that of kidneys having had a warm ischemic period of less than 5 minutes. After retransplantation all kidneys showed a sufficient blood flow and immediate production of urine during the test period of 3 hours.

[Morphological research on DMSO-perfused kidneys]. / Morphologische Untersuchungen an DMSO-perfundierten Nieren.

It is reported on the morphological investigations of kidneys which had been perfused with the cryoprotective dimethylsulfoxide (DMSO). Some of these kidneys were stored for 72 hours at -4.5 degrees C and then retransplanted. The light-microscopic and electron-optical findings show considerable changes of the cells of the proximal tubulus epithelium and the collecting tubules. These in most cases focal findings of different extension do not differ on principle from the results in preservation techniques without DMSO. The dilatation of the basal labyrinth of the tubulus cell as well as the fissuration and vacuolization in the cytoplasm give references to a passive transport of substance by the cell. The results of the DMSO-perfused and at -4.5 degrees C stored kidneys show that for a beginning of the function an optimal perfusion must be supposed. On the one hand a sufficient concentration of freezing defense remedies in the renal tissue is necessary, on the other hand an optimum removal of the DMSO in the reperfusion is necessary, in order to keep the osmotic load of the kidney as low as possible.

[Effect of the stable prostacyclin analog (iloprost) on survival of ischemically-stressed swine kidney transplants]. / Einfluss eines stabilen Prostazyklin-Analogons (Iloprost) auf die Konservierung ischämisch-belasteter Schweinenierentransplantate.

Kidneys of 5 pigs were pretreated in situ with Iloprost (Fa. Schering) (0.5 micrograms X kg-1 X min-1) and exposed to a warm ischaemia time of 45 minutes. The perfusion behaviour of these kidneys during the initial fall current perfusion and hypothermic machine perfusion for 24 hours was to be compared with that of kidneys with a warm ischaemia time of less than 5 minutes. After retransplantation in all kidneys a good blood supply and an immediate urine production was to be seen for the duration of the experiment of 3 hours.

[Extended storage preservation of swine kidneys to 72 hours using iloprost]. / Die Verlängerung der Lagerungskonservierung von Schweinenieren auf 72 Stunden durch Einsatz von Iloprost.

The intraaortal infusion of Iloprost (1 micrograms/kg X min) for the duration of 15 minutes leads to an increase of the renal hematorrhea by 85.2%, to a decrease of the renal resistance by 51.6% and to a slight decrease of the average arterial blood pressure by 13.3%. After a 72-hour hypothermic storage preservation under addition of Iloprost the renal blood supply after retransplantation corresponded to the initial values of the blood flow before nephrectomy. The production of urine began after 1-2 minutes. Enzyme investigations of the transplant urine resulted in an increased excretion of the cytosolic enzymes, the structure-bound enzymes, however, remained in the area of the norm. The investigation of the electrolytes of the urine showed a hypersodiuria as well as a hypopotassiuria and calciuria. As to urea and creatinine the values were below the parameters used for comparison. In the contralateral kidneys used as control kidneys no blood supply developed after retransplantation. The application of Iloprost for the conditioning of donor kidneys is very well suited and shows some advantages compared with the preparation used up to now. The prolongation of the hypothermic storage preservation to 72 hours seems to be possible by the application of Iloprost.

[Dye concentration measurements for the determination of leakage during and following normothermic cytostatic perfusion in the treatment of tumors of the extremities]. / Farbstoffkonzentrationsmessungen zur Abstrombestimmung während und nach der normothermen zytostatischen Perfusion zur Behandlung von Extremitätentumoren.

The regional normothermic cytostatic perfusion with 3000 mg Methotrexate and 1.5 mg Vincristine under rescue conditions (leucovorine) during 120 minutes was carried out in patients with malignant melanoma stage II by Sylven or other tumors of the lower extremities in the surgical university hospital Halle since 1980. Dye concentration measurements with indigo carmine for monitoring the isolation between systemic circulation and perfusion circulation were carried out during and after cytostatic perfusion. The measurements took place with a Spekol 10 of the VEB Carl Zeiss, Jena, by wave-length of 605 nm. The leakage streams of 30 perfusions amounted from 0 to 46% during the phase - regional perfusion. The dye quantity which was secreted by the kidneys during 16 hours post perfusion despite plentiful lavage of the extremity (MTX quantity) amounted from 2 to 7%.

[Comparative temperature measurement by thermoprobes and infrared pyrometry in the rewarming of frozen kidneys using short wave generators]. / Vergleichende Temperaturmessungen durch Thermosonden und Infrarot-Pyrometrie bei der Wiedererwärmung eingefrorener Nieren mittels Kurzwellen-generatoren).

Mini pigs' kidneys were frozen to -20 degrees C after initial hypothermic perfusion and cryopreparation with dimethyl sulphoxide. They were subsequently thawed out with short-wave radiation. During this procedure continuous temperature measurement is only possible using infra-red pyrometry without physical contact. After completion of short-wave irradiation at ca. 4 degrees C the surface and internal temperatures are measured with thermoelements. In comparison with measurement by thermoprobes, infra-red pyrometry proves to be quite practicable, with certain limitations. If a homogeneous distribution of temperature in the organ is assumed; the internal temperature could be calculated from the surface temperature. Also, continuous observation of temperature changes ist possible.

[Ultrasonic Doppler methods of blood flow studies of the arterial circulation from the aorta up to the kidney parenchyma in animals]. / Untersuchungen des Strömungsverhaltens des Blutes in der arteriellen Strombahn Ausgehend von der Aorta bis zum Nierenparenchym mit dem Ultraschall-Doppler-Verfahren im Tierversuch.

The Doppler method of ultrasonography was used in experimental investigations to examine the circulator behaviour at various points in the arterial system in the retroperitoneum as fast as the kidney in animals with normal circulation. This enabled reproducible Doppler curves to be determined. It remains to be seen to what extent characteristic curve patterns exist for e.g. partial or subtotal vascular occlusion. For the future it will be especially important to determine the flow curves in the cortical region of the renal parenchyma as an area of small and very small vessels, for this can give us important information on the circulation of blood in the individual segments of the kidney.

[Permeation of formaldehyde (methanal) through supravital and preserved tissue]. / Permeation von Formaldehyd (Methanal) durch supravitales und präserviertes Gewebe.

Allogenic and xenogenic tissues can be preserved with acetate buffered formaldehyde solution 1,332 mol/l and pH 5,60. The permeation of methanol molecules through the tissue was analysed with a double chamber research arrangement with a rotating set-up. The coefficient of diffusion of the formaldehyde (methanal) through the wall of the aorta descendens of pigs was calculated by means of the first Fick principle from the obtained measured particulars.