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D Abendroth

Publications and source records attributed to D Abendroth.

At least 55 records · Page 3Linked to original sources
PubMed1994

Long-term follow-up of lipid metabolism and rheologic properties after successful pancreas and kidney transplantation.

The long-term effect of pancreatic and kidney transplantation (spkt) on blood viscosity, lipid metabolism and skin microcirculation in insulin-dependent diabetes mellitus (IDDM) was studied because impaired rheological properties of blood may play a role in the development of diabetic micro- and macroangiopathy. 46 IDDM-patients (16 f/30 m; 23 +/- 34 y mean duration of diabetes; 60 +/- 14 mos mean follow up period) underwent spkt (Gr.I: n = 28) or solitary kidney (Gr.II: n = 18) transplantation, and were compared with healthy controls (C). Rheological measurements were performed with Mooney-Ewart rotation-viscosimeter determining whole blood viscosity (WBV), at shear rates 1, 5, 10, 20, 50, 100, 200 sec(-1). Triglycerides, total and HDL-, LDL- and VLDL cholesterol and fibrinogen were measured. Microcirculation was estimated by transcutaneous oxygen tension measurement (tcpO2) and laser speckle method, in the forefoot area. Hemoglobin A1 was normalized only in group I (I: 7.2 +/- 0.2%; II: 8.3 +/- 0.3%; C: < 8%). WBV at low shear (1, 5, 10) was increased in both groups, when compared to healthy controls (I: 12.4 +/- 2; 12.5 +/- 1; 6.8 +/- 0.5 mpas; II: 18.7 +/- 2; 13.4 +/- 15; 9.4 +/- 1 mpas; C: 7.5 +/- 0.5; 6.7 +/- 0.3; 5.4 +/- 0.2 mpas; P < 0.05). Plasma fibrinogen was elevated in both groups compared to normals: (I: 384 +/- 19; II: 448 +/- 20; C: 250 +/- 50 mg/dl; P < 0.05). There was a positive influence of spkt on skin microcirculation: tcpO2/prior tx: I: 44 +/- 3; II: 49 +/- 6 mmHg; post tx: I: 59 +/- 4; II: 42 +/- 3 mmHg. Laser speckle prior tx I: 3.3 +/- 0.3; II: 4.7 +/- 0.2 rel. U.; post tx: 3.8 +/- 0.2; II: 4.3 +/- 0.2 rel. U. Patients with progression of angiopathy showed still higher fibrinogen and shear rates (P < 0.05). There was no significant difference for total HDL-, LDL- and VLDL cholesterol. Despite normalization of glucose metabolism and significant improvement of microcirculation in spkt patients, fibrinogen and the shear rates are increased indicating a persisting "individual" vascular risk. It is suggested that an additional hemorheological approach in the treatment posttrransplant might prevent the progression of vascular complications.

Adult↗
PubMed1994

Production of proinflammatory cytokines and adhesion molecules in ex-vivo xenogeneic kidney perfusion.

Xenogeneic transplantation of solid organs is limited due to hyperacute rejection. In concordant systems, the mechanisms of rejection can be studied due to cross-reactivity of mediators with anti-human monoclonal antibodies. The aim of this study was to obtain information about the kinetics of proinflammatory cytokines and production of soluble adhesion molecules in the acute phase of reperfusion, eight kidneys from rhesus monkeys were perfused ex-vivo with human blood (group B/0) for 1 hour in a closed system. Blood levels of IL-1b, IL-6, TNFalpha, soluble ICAM, and E-selectin were measured using an ELISA technique under steady-state conditions. Cytokine levels rose significantly within the 60-min interval (IL-1b, 6.1 +/- 2.6-161.1 +/- 98.5 pg/ml; IL-6, 30.2 +/- 7.7-274.2 +/- 75.8 pg/ml; TNFalpha, 544.2 +/- 363.6-1651.0 +/- 25.7 pg/ml; P < 0.05). Immediately after the beginning of reperfusion, soluble ICAM-1 and selectin levels were abnormally high and rose constantly throughout the observation period, reaching significance at 60 min. High levels of proinflammatory cytokines may lead to an induction of adhesion molecules, thus, upregulating the leukocyte-endothelial interaction in a complement-independent mechanism. Specific pretreatment with monoclonal antibodies against ICAM-1, LFA-1, or other soluble mediators may be useful in down-regulating hyperacute rejection in trans-species transplantation.

Animals↗
PubMed1993

Noncontact determination of skin blood flow using the laser speckle method: application to patients with peripheral arterial occlusive disease (PAOD) and to type-I diabetics.

The laser speckle method allows the noncontact determination of skin blood flow and its dynamics from a distance of 5 cm. The method is based on the time dependency of the speckle pattern formed by the scattered light of a 5 mW He-Ne laser (632.8 nm). Utilizing the speckle intensity measured through a pinhole, an electronic circuit generates an output signal denoted as blood flow parameter B. All measurements were carried out on the foot dorsum during steady-state, ischemia, and reactive hyperemia induced by a 3-min arterial occlusion. The investigations were carried out in four groups: healthy subjects, asymptomatic smokers, PAOD-patients, and type-I diabetics (D) with severe late complications. As shown by parallel measurements with the tcpO2-method, the initial value Binit of the blood flow parameter B indicates the steady-state blood flow. Binit decreases significantly from 5.95 +/- 2.55 (S.D.) for the control to 4.07 +/- 1.69 (PAOD) and 3.81 +/- 1.51 (D). The half-time BTrh for the increase of B at the beginning of the reactive hyperemia is significantly increased from 4.10 +/- 2.06 s (control) to 14.5 +/- 15.4 s (smokers), 17.6 +/- 32.7 s (PAOD), and 5.31 +/- 3.55 s (D). Other characteristic values such as peak value and time of peak during the reactive hyperemia as well as the final steady-state value and the time of its achievement exhibit similar effects. The correlation coefficients between the different characteristic values obtained from the laser speckle method indicate that the characteristic times of the dynamics and the absolute values of B vary separately and provide supplemental information. A two-dimensional representation of the characteristic values facilitates the differentiation between the four measured groups.

Adult↗
PubMed1993

Cross-sectional study of peripheral microcirculation in diabetic patients with microangiopathy: influence of pancreatic and kidney transplantation.

Diabetic vascular lesions and peripheral autonomic neuropathy are both closely linked to long-term metabolic control of diabetes. Transcutaneous oxygen tension (PtcO2) measurements were made to elucidate whether autonomic neuropathy disturbs the cutaneous microcirculatory blood flow, and whether long-term glucose normalization ameliorates such impairment. Twenty-eight type 1 (insulin-dependent) diabetic patients in whom clinically significant macroangiopathy had been excluded by angiography were studied, subdivided into group A (n = 14; before simultaneous pancreas/kidney transplantation (SPKT); mean age 35 years, range 22-51 years; mean duration of diabetes 24 years, (range 15-32) years and group B (n = 14; mean 31 months, range 2-101 months, after successful SPKT; mean age 35 years, range 19-56 years; mean duration of diabetes 22 years, range 14-29 years). On addition there was a group (group C) of age- and sex-matched healthy control subjects (n = 14; mean age 35 years, range 23-62 years). PtcO2 measurements included basal recordings at 44 degrees C on the leg and the foot, functional recordings at 44 degrees C after arterial occlusion of the limb for 4 min, measurements during breathing 5 l oxygen per minute and finally while standing up (stand up dP20/dt). All subjects underwent extensive cardiac autonomic testing. In this cross-sectional study the recordings of basal values and of the functional parameters after arterial occlusion and during breathing oxygen did not differ significantly between groups A, B and C.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Diabetic neuropathy 3 years after successful pancreas and kidney transplantation.

Twenty-seven patients with successful transplantation and a control group of 14 patients with early rejection of the pancreas graft but functioning kidney graft were examined in a prospective study for 3 yr. Before transplantation, all patients had long-standing type I diabetes with advanced secondary complications, including end-stage diabetic nephropathy. After transplantation in the patients of both groups, kidney function was almost normal. Mean HbA1 levels were normal in the group with pancreas graft survival. In the control group, HbA1 levels were, on average, 1.5% higher compared with the group with pancreas survival (P = 0.00005). After 3 yr, the patients with functioning pancreas graft showed fewer symptoms (mean difference 1.0 in a symptom score ranging from 0 to 16, P = 0.004) compared with the control group. No statistically significant difference between both groups concerning clinical signs of polyneuropathy could be observed. In the pancreas and kidney transplantation group, peroneal and median nerve conduction velocities increased 7.2 m/s (P < 0.01) and 3.5 m/s (P < 0.05), respectively, whereas no increase was registered in the control group. The change of median and sural sensory nerve conduction velocities, peroneal and median compound muscle action potentials, and sural and median sensory action potentials was insignificant. In conclusion, although the improvement of clinical symptoms and neurophysiological signs of polyneuropathy was modest in the pancreas and kidney transplantation group, our data suggest that successful pancreas transplantation is able not only to halt the progression of diabetic polyneuropathy but also to improve it to some extent even at a far advanced stage.

Action Potentials↗
PubMed1993

[Damage to a stent caused by a Shaldon catheter].

Recently, stent implantation has been used with increasing frequency in the treatment of central venous stenoses in patients undergoing chronic haemodialysis. Stent localisation may interfere with central venous catheterisation. CASE REPORT. In a 57-year-old female haemodialysis patient, a filiform stenosis of the right subclavian vein was treated by percutaneous transvenous angioplasty and stent implantation. Five weeks later, she presented with a thrombosed dialysis shunt. A Shaldon catheter was implanted via the right internal jugular vein. Post-procedure radiographs showed extensive stent damage without stent dislocation or thrombosis. CONCLUSION. Stent localisation has to be considered in the event of later central venous catheterisation. Venous puncture should be carried out under fluoroscopic control if catheter placement on the side of the stent is inevitable.

Catheters, Indwelling↗
PubMed1992

[Status of treatment with free radical scavengers following kidney and pancreas transplantation].

AIM OF THE STUDY: The frequency of acute renal failure (ARF) after preservation and kidney transplantation is rather high. The etiology of an ARF is an interaction of multiple mechanisms as donor conditions, explantation procedure, duration of ischemia and reperfusion injury. Different experiments demonstrated, that the damage produced by reperfusion can be prevented by the scavenger of free radicals, the enzyme superoxide dismutase (SOD). PATIENTS AND METHODS: After a double blind study, using consecutive intraarterial bovine SOD (n = 100) in kidney transplantation, showing a trend in favour to the SOD treated group, especially when long-time stored kidneys (> 30 h) had been grafted, a second study was designed to evaluate the efficiency of intravenous recombinant human SOD in the protection from ARF. This study (n = 180) was split into two different trials, double blind and randomized in itself: (A) grafts with cold ischemia time lower or equal 30 hrs., (B) cold ischemia more than 30 hrs. All grafts were preserved with Euro-collins. The study substances were either placebo or 200 mg rh-SOD (Grünenthal GmbH, FRG), given 10-2 minutes prior reperfusion intravenously. Parameters causing an ARF were equal and well comparable in both groups. RESULTS: Concerning early graft function there was no difference in study A between placebo and rh-SOD group. In study B the average and median of the day creatinine dropped the first time without interference of hemodialysis, showed a trend in favour to the rh-SOD group. If placebo was given only 19% of the grafts gained function within the first week, when rh-SOD was applied 47% functioned in the first week. The lack of significant benefit from SOD treatment could be explained by the dependency of the proportion of the total injury caused by reperfusion compared with the proportion resulting from ischemic injury per se. The rh-SOD group showed a better 3 years graft survival rate (+16%). CONCLUSIONS: It seems rh-SOD is able to augment the early graft function and is helpful to reduce the ARF frequency when long-time stored cadaveric kidneys have to be transplanted. These promising results encourage us to continue the study in protocol B to get greater numbers and definitive results.

Acute Kidney Injury↗