M. Kallerhoff

EXPRESSION OF METALLOPROTEINASE 2 AND 9 AND THEIR INHIBITORS IN RENAL CELL CARCINOMA

Degradation of the extracellular matrix is necessary for invasion and metastasis by cancer cells. Two gelatinolytic matrix metalloproteinase enzymes, MMP-2 and MMP-9, are supposed to be key enzymes in this process. The purpose of this study was to correlate the presence of MMP-2, MMP-9 and their inhibitors with the tissue inhibitors of metalloproteinases TIMP-1 and TIMP-2 RNA using reverse transcriptase PCR technique with tumor stage in 17 samples of renal cell carcinoma. The ratio of tissues expressing MMP-2 and MMP-9 to those expressing TIMP-1 and TIMP-2 was defined to be 1 in normal kidney tissue. This MMP:TIMP ratio was significantly increased to 2.43 (standard deviation, SD = 0.8) in locally confined renal cell carcinoma and to 4.86 (SD = 1.1) in advanced carcinoma (p <0.01). In primary tumor cell lines the ratio of MMP:TIMP expression was 3.44 (SD = 0.6). These data suggest that the balance of MMP-2 and MMP-9 to TIMP-1 and TIMP-2 expression is an essential factor in the aggressiveness of renal cell carcinoma.

Detection of renal ischemic lesions using Gd-DTPA enhanced turbo FLASH MRI: Experimental and clinical results

PURPOSE Our goal was to investigate the role of Gd-DTPA-enhanced dynamic MRI in the evaluation of renal ischemic lesions. METHOD With a turbo FLASH sequence before and after injection of Gd-DTPA, nine foxhound dogs after 60-120 min of renal ischemia underwent MR examination. In addition, five patients with a tumor in a solitary kidney were examined before and after nephron-sparing renal surgery to evaluate renal perfusion and function. The experimental and clinical findings were correlated with conventional measurements of kidney function and with histological findings. RESULTS Complete renal ischemia leads to a poor corticomedullary differentiation in Gd-DTPA-enhanced turbo FLASH MRI. The signal-intensity-versus-time plots of kidneys with significant postischemic changes show a less steep increase of signal intensity in the cortex and a steeper increase of signal intensity in the medulla than those of normal kidneys. CONCLUSION Dynamic MRI demonstrate renal morphology and reflect the functional status of renal vasculature.

Construction and experimental application of a catheter for selective arterial kidney perfusion in situ

SummaryIn order to improve dog kidney perfusion in situ with a protective solution, a perfusion catheter was constructed which allowed continuous pressure measurement in the center of the catheter tip during perfusion. Using this catheter, the equilibration of the extracellular space with a protective solution (HTK solution) was found to be pressure dependent. Continuous pressure and resistance control is therefore a prerequisite for reliable organ protection.

Post-ischemic renal function after kidney protection with the HTK-solution of Bretschneider

SummaryThe cardioplegic solution HTK of Bretschneider was used for canine kidney protection. The kidneys were perfused with this solution for 6–10 min prior to the induction of ischemia. The kidneys were left in-situ for 60, 90, 120 and 135 min ischemia time at a temperature of 25–34°C (n=13). As a control group we used unilateral nephrectomized dogs (n=9). After unilateral nephrectomy an elevated plasma creatinine in comparison to preoperative values was observed. After 60 and 90 min under HTK-protection the postoperative plasma creatinine was not elevated compared to the control group. After 120 min of ischemia creatinine level was slightly increased to an average of 2.1 mg% on the first and second postoperative day. These experiments indicate the protective effect of the cardioplegic solution for canine kidney preservation in situ.

Metabolic, energetic and structural changes in protected and unprotected kidneys at temperatures of 1 °C and 25 °C

SummaryIn 110 canine kidneys, we examined the time course of energy rich phosphates, lactate, intrarenal ph and renal morphology with Euro-Collins-or with HTK-protection of Bretschneider and compared these findings with unprotected kidneys during complete ischemia at 1 °C and at 25 °C. Both kidney protective solutions prolonged energyrich phosphate-decline by a factor of 3–4 compared with that of unprotected kidneys. The lactate increase was greater in Euro-Collins-protected kidneys than in HTK-protected and in unprotected kidneys, leading to pH values of 6.5 in Euro-Collins and to 6.4 in unprotected kidneys after 24 hours, in contrast to a pH-value of 7.3 with HTK-protection. This may be the reason for structural deterioration seen in unprotected and in Euro-Collins-protected kidneys after 12, and 48 h of ischemia at 1 °C, whereas in HTK-protected kidneys a sufficient preservation of structure can be seen. In one human kidney, protected with Euro-Collins-solution, we were able to show that at 1 °C intrarenal pH and lactate accumulation is similiar to the levels in canine kidneys. In Euro-Collins preserved kidneys lactate accumulation at 25 °C is even greater than at 1 °C, leading to inhibition of energy metabolism and to structural deterioration, whereas HTK-solution, because of its high buffer concentration, is able to maintain ischemic metabolism leading to sufficient protection of intrarenal pH and of adenine nucleotides as well as structural protection at 1 °C and at 25 °C.

Unusual Bilateral Renal Histiocytosis: Extranodal Variant of Rosai-Dorfman Disease

In 1969 Rosai and Dorfman described a benign pathological entity termed sinus histiocytosis with massive lymphadenopathy mainly at the cervical area associated with fever, leukocytosis and polyclonal hypergammag1obulinemia.l Histopathologically the condition is due to an inflammatory infiltrate of a subtype of S-100 positive histiocytes characterized by hemophagocytosis. Most cases occur during the first and second decades of life. Extranodal manifestation is rare.2 The disease usually resolves spontaneously with low dose corticoid therapy. CASE REPORT

Microcalorimetric measurements carried out on isolated tumorous and nontumorous tissue samples from organs in the urogenital tract in comparison to histological and impulse-cytophotometric investigations

In this comparative study, microcalorimetric measurements were carried out on a total of 96 tumorous and nontumorous tissue samples taken from organs of the urogenital tract using a thermal activity monitor (TAM). Changes in the heat emission of the tissue samples were measured at 1-min intervals and graphically displayed as a function of time. The aim of the study was to compare the microcalorimetric results with impulse-cytophotometric and histological findings and provide evidence for the metabolic activity of tumorous and nontumorous tissue. In order to obtain the variation in metabolic activity, the maxima (Pmax) of the curves were determined as a value of the maximum thermal power of a tissue sample, the mean values (P) were determined by the mean thermal power and the contour integrals (W) were defined by the behavior of the energy reserves and their mobilization. The first part of the study was carried out to investigate whether tumorous and nontumorous tissue samples differ in general according to their metabolic activity. We discovered, using the parameters described above, that in general tumorous tissue exhibited a higher metabolic activity than nontumorous tissue samples. For example, both W and P in tumorous prostate tissue samples were eightfold higher and the (Pmax) value was 8.4-fold higher than in normal tissue. Additional investigations on testicle and kidney tissues were performed to find a possible correlation between microcalorimetric results and histological grading. We found that an increasing malignancy correlated with a higher metabolic activity of the tissue. Based upon these results were were able to differentiate the various histological gradings of these tumorous tissues by microcalorimetric measurements. The results show it is possible to differentiate between normal and tumorous tissue samples by microcalorimetric measurement based on the distinctly higher metabolic activity of malignant tissue. Furthermore, microcalorimetry allows a differentiation and classification of tissue samples into their histological grading. With the help of microcalorimetry, it might be possible in future to detect and record the metabolic processes of isolated tissue structures and changes in these activities as a result of medical intervention such as cytostatic treatment.

Urinary LDH-release for evaluation of postischemic renal function

SummaryFollowing renal ischemia under protection, the perfusion of the tubular system increases concomitant to the rise of GFR. The transport into urine of enzymes entering the tubular lumen due to ischemic injury is dependent on tubular flow. Thus, we examined if in the early post-ischemic phase urinary enzyme determinations can contribute to the evaluation of a changing tubular washout. Canine kidneys were perfused with different protective solutions and subsequently rendered ischemic. From the beginning of reperfusion the endogenous creatinine clearance, the urine minute volume and the urinary LDH-concentration were determined. The urinary LDH-concentration allowed only a rough assessment of renal ischemic damage. The adjustment of the urinary LDH amounts to the GFR resulted in a better graduation according to the ischemic stress. With such a standardized LDH parameter the urinary LDH release was somewhat lower on the average when L-aspartate was added to the HTK solution in place of chloride. In conclusion, during the early postischemic recovery after renal protection the examination of the urinary enzyme release may be a useful diagnostic means for the assessment of the extent of the ischemic injury if an appropriate frame of reference is applied.

A new method for conservative renal surgery — experimental and first clinical results

ZusammenfassungZur Verlängerung der renalen Ischämie stehen bisher zwei Verfahren zur Verfügung: 1) eine Oberflächenkilhlüng mit Eis and 2) eine Perfusionskühlung mit einer extrazellulären Losung. Beide Methoden nutzen nur das Prinzip der Stoffwechselsenkung durch Kühlung. Während der Wiedererwärmung bei der Operation geht der Ischämieschutz verloren oder die Niere muß erneut gekiihlt werden. Deshalb sollte eine neue Protektionslösung den Energieverbrauch zusätzlich zur Kühlung auch durch ihre Zusammensetzung senken. Bei offenen Herzoperationen wird die HTK-Lösung nach Bretschneider bereits klinisch angewendet. In 71 Experimenten an Hundenieren wurde die Ischämiezeit durch diese Lösung von 15 auf 120 min bei 35°C and von 45 auf 360 min bei 25°C. verlängert. Nach 120 min Ischämie bei 30°C betrug die glomeruläre Filtrationsrate ca. 20 ml/min 100gFG innerhalb von 3 h Reperfusion. Nach 6 Tagen postoperativ war die GFR wieder 40 ml/min 100gFG. Es konnte kein ischämischer Schaden durch histologische Untersuchungen mehr festgestellt werden. Der klinische Nutzen dieser Methode konnte in 7 klinischen Anwendungen gezeigt werden. Die Ischamiezeit betrug bis zu 113 min and das Kreatinin lag zwischen 0,8 and 2,4 mg% am 6. postoperativen Tag. Dieses Protektionsverfahren führt also zu einer verbesserten Nierenfunktion in der postoperativen Phase. Eine längere Ischämiezeit wird von der Niere vertragen, and unter Anwendung dieser Technik wird eine ausgezeichnete Übersichtlichkeit während der Nierenoperation erreicht, was eine radikale Tumorexzision erleichtert.SummarySo far two methods for prolonging the tolerance of renal ischemia are available: 1) surface cooling with crushed ice and 2) perfusion cooling with an extracellular-like solution. Both methods use only the principle of reducing metabolism through cooling. While rewarming during surgery the ischemic protection is lost, or the kidney must be cooled once again. Therefore, a new preservation solution should reduce energy consumption due to its composition in addition to cooling. For open heart surgery, the HTK solution by Bretschneider is already used clinically. In 71 dog kidney experiments, the ischemic time kidneys could tolerate was prolonged by this solution from 15 to 120 min at 35°C and from 45 to 360 min at 25°C. After 2h of ischemia at 30°C glomerular filtration rate was about 20 ml/min · 100 gww within 3 h of reperfusion. After six postoperative days the filtration rate was 40 ml/min · 100 gww. No ischemic damage could be recognized by histological investigations. The clinical effectiveness of this method was shown in 7 clinical applications. Ischemic duration lasted up to 113 min, and blood creatinine was between 0.8 and 2.4 mg% at the 6th postoperative day. Use of this preservation technique thus leads to improved kidney function immediately following operation. Longer ischemia can be tolerated by a kidney thus protected, and using this technique excellent visibility can be achieved during intrarenal surgery, simplifying, for example, tumor extirpation.

In vitro investigations of new therapeutic agents on bladder tumor cell lines

In this study sensitivity of human transitional cancer cells to the anticancer agent paclitaxel, an antimicrotubular drug, and to gallium nitrate, a group IIIa metal, was compared. to that of the standard MVAC (methotrexate, vinblastine, doxorubicin and cisplatin) drugs. The reduction of cell proliferation was evaluated after 48 h of incubation of six different cell lines with each agent using the mean transit time (MTT) assay. We investigated both monolayers and spheroids. Paclitaxel showed significantly higher growth inhibitory effects on monolayers than vinblastine, both agents targeting the antimicrotubular apparatus. This could not be reproduced on spheroids, where a survival fraction of 50% was observed even at high concentrations (10 μM). High concentrations of gallium nitrate were needed to achieve sufficient toxicity. These concentrations are beyond the concentration achievable by systemic application. Our findings suggest that paclitaxel may be a clinically useful agent for systemic and intravesical use in bladder cancer.