472 results on '"Heidenreich, S."'
Search Results
252. Shear-induced dynamic polarization and mesoscopic structure in suspensions of polar nanorods.
- Author
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Heidenreich S, Hess S, and Klapp SH
- Subjects
- Biopolymers chemistry, Suspensions chemistry, Models, Chemical, Nanotubes chemistry
- Abstract
We investigate the spatiotemporal behavior of sheared suspensions of rodlike particles with permanent dipole moments. Our calculations are based on a self-consistent hydrodynamic model including feedback effects between orientational motion and velocity profile. The competition between shear-induced tumbling motion and the boundary conditions imposed by plates leads to oscillatory alignment structures. These give rise to a spontaneous time-dependent polarization generating, in turn, magnetic fields. This novel shear-induced effect is robust against varying the boundary conditions. The field strengths are of a measurable magnitude for a broad parameter range.
- Published
- 2009
- Full Text
- View/download PDF
253. Influence of heme oxygenase-1 on microcirculation after kidney transplantation.
- Author
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Hölzen JP, August C, Bahde R, Minin E, Lang D, Heidenreich S, Dietl KH, and Spiegel HU
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- Animals, Creatinine blood, Disease Models, Animal, Heme Oxygenase-1 genetics, Hemin pharmacology, Ischemic Preconditioning methods, Kidney pathology, Kidney Transplantation pathology, Male, Microcirculation physiology, Nitric Oxide Synthase metabolism, Rats, Rats, Inbred Lew, Reperfusion Injury physiopathology, Urea blood, Heme Oxygenase-1 metabolism, Kidney blood supply, Kidney Transplantation physiology, Reperfusion Injury prevention & control
- Abstract
Background: Cytoprotective proteins, such as heme oxygenase-1 (HO-1), play a decisive role in ischemia-reperfusion injury during kidney transplantation. The aim of this study was to investigate the impact of heme oxygenase-1 on microcirculation and on ischemia-reperfusion injury in an isogenic kidney transplantation rat model., Materials and Methods: Seventy male Lewis rats were distributed into three groups. In Group 1(control), the kidneys were only mobilized. In Groups 2 and 3, bilateral nephrectomy was performed, and a kidney from another Lewis rat was orthotopically transplanted on the left side. The donor animals in Group 3 received preconditioning with the HO-1 inductor hemin. 24 h after reperfusion graft function and morphology were examined. Microcirculation was investigated by in vivo microscopy of the renal surface 1 h after reperfusion., Results: HO-1 preconditioning led to significantly lower serum creatinine and serum urea, as well as less histological damage and inducible nitric oxide synthase expression. Microcirculation was improved by a significant enlargement of the vascular diameter and an increase of the capillary flow., Conclusions: Treatment with hemin improves microcirculation by induction of HO-1 and reduces ischemia-reperfusion injury after kidney transplantation. HO-1 induction was shown to be a promising approach in the preconditioning of donor kidneys.
- Published
- 2008
- Full Text
- View/download PDF
254. Polar nano-rods under shear: from equilibrium to chaos.
- Author
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Grandner S, Heidenreich S, Hess S, and Klapp SH
- Subjects
- Computer Simulation, Electromagnetic Fields, Nanotubes ultrastructure, Nonlinear Dynamics, Radiation Dosage, Shear Strength, Models, Chemical, Models, Molecular, Nanotubes chemistry, Nanotubes radiation effects, Static Electricity
- Abstract
The orientational dynamics of rod-like particles with permanent (electric or magnetic) dipole moments in a plane Couette shear flow is investigated using mesoscopic relaxation equations combined with a generalized Landau free energy. The free energy contribution due to the coupling between average alignment and dipole orientation is derived on a microscopic basis. Numerical results of the resulting eight-dimensional dynamical system are presented for the case of longitudinal dipoles and thermodynamic conditions where the equilibrium state is a (polar or non-polar) nematic. Solution diagrams reveal presence of a large variety of periodic, transient chaotic, and chaotic dynamic states of the average alignment and dipole moment, respectively, appearing as a function of Deborah number and tumbling parameter. Compared to rods without dipoles we observe a significant preference of out-of-plane kayaking-tumbling states and, generally, a higher sensitivity to the initial conditions including bistability. We also demonstrate that the average (electric) dipole moment characterizing most of the observed states yields electrodynamic (magnetic) fields of measurable strength.
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- 2007
- Full Text
- View/download PDF
255. [Daily problems involving contact with terminally ill patients with renal failure].
- Author
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Moeller MJ, Heidenreich S, Gladziwa U, and Floege J
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- Arteriovenous Shunt, Surgical methods, Catheters, Indwelling, Graft Occlusion, Vascular diagnosis, Graft Occlusion, Vascular etiology, Graft Occlusion, Vascular therapy, Heart Diseases diagnosis, Heart Diseases etiology, Heart Diseases therapy, Humans, Kidney Failure, Chronic diagnosis, Kidney Failure, Chronic etiology, Kidney Transplantation, Opportunistic Infections diagnosis, Opportunistic Infections etiology, Opportunistic Infections therapy, Peritoneal Dialysis methods, Postoperative Complications diagnosis, Postoperative Complications etiology, Postoperative Complications therapy, Prognosis, Renal Dialysis methods, Risk Factors, Emergencies, Kidney Failure, Chronic therapy
- Abstract
Practitioners and physicians working in emergency rooms are often confronted with dialysis patients or patients who have received a kidney transplant. For dialysis patients, the mode of dialysis treatment needs to be assessed and dialysis access should be secured. Furthermore, the indications for the next dialysis treatment need to be determined. Dialysis patients often present themselves because of fluid overload, hypo- or hypertensive episodes, electrolyte disturbances, fever or cardiovascular events. Patients undergoing continuous peritoneal dialysis are at an increased risk of infection of the catheter or of peritonitis. Patients with a renal transplant require continuation of their immunosuppression and the function of the transplant should be monitored. These patients often present with infections in which case the degree of immunosuppression may need to be reduced. Vaccinations as well as an increased risk for malignancies require special attention in these patients.
- Published
- 2007
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256. Boundary conditions for fluids with internal orientational degrees of freedom: apparent velocity slip associated with the molecular alignment.
- Author
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Heidenreich S, Ilg P, and Hess S
- Abstract
Boundary effects are investigated for fluids with internal orientational degrees of freedom such as molecular liquids, thermotropic and lyotropic liquid crystals, and polymeric fluids. The orientational degrees of freedom are described by the second rank alignment tensor which is related to the birefringence. We use a standard model to describe the orientational dynamics in the presence of flow, the momentum balance equations, and a constitutive law for the pressure tensor to describe our system. In the spirit of irreversible thermodynamics, boundary conditions are formulated for the mechanical slip velocity and the flux of the alignment. They are set up such that the entropy production at the wall inferred from the entropy flux is positive definite. Even in the absence of a true mechanical slip, the coupling between orientation and flow leads to flow profiles with an apparent slip. This has consequences for the macroscopically measurable effective velocity. In analytical investigations, we consider the simplified case of an isotropic fluid in the Newtonian and stationary flow regime. For special geometries such as plane and cylindrical Couette flow, plane Poiseuille flow, and a flow down an inclined plane, we demonstrate explicitly how the boundary conditions lead to an apparent slip. Furthermore, we discuss the dependence of the effective viscosity and of the effective slip length on the model parameters.
- Published
- 2007
- Full Text
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257. Dynamic electric polarization of nematic liquid crystals subjected to a shear flow.
- Author
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Grandner S, Heidenreich S, Ilg P, Klapp SH, and Hess S
- Abstract
The effect of coupling between the dipole moment and the orientation is explored based on a relaxation equation for the second rank alignment tensor characterizing the molecular order in liquid crystals and a corresponding equation for the electric polarization. The orientational dynamics leads to a time dependence of the electric polarization. We propose a possibility to measure these effects via the resulting magnetic fields of the magnitude |B| approximately equal to 10(-9)T . Furthermore, the presence of the electric polarization modifies the orientational dynamics as demonstrated in solution phase diagrams.
- Published
- 2007
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258. Stress associated proteins metallothionein, HO-1 and HSP 70 in human zero-hour biopsies of transplanted kidneys.
- Author
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August C, Brockmann J, Vowinkel T, Wolters H, Dietl KH, Levkau B, Heidenreich S, Lang D, and Baba HA
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- Adult, Aged, Aged, 80 and over, Apoptosis, Biopsy, Humans, Immunohistochemistry, Kidney pathology, Metallothionein analysis, Middle Aged, HSP70 Heat-Shock Proteins analysis, Heme Oxygenase-1 analysis, Kidney chemistry, Kidney Transplantation
- Abstract
Light microscopic alterations reflecting both previous and preservation-induced changes in the donor organ are usually not very distinctive. The ischemia/reperfusion-associated injury depends primarily on the conditions of donor organ preservation. The present study examined human kidney biopsies with special attention paid to the molecular mechanisms of preservation-induced injury preceding reperfusion. Stress-associated proteins hemeoxygenase-1 (HO-1), heat shock protein 70 (HSP 70), and metallothionein (MT) were studied in human zero-hour biopsies of transplanted kidneys prior to reperfusion in 29 patients. Protein expression was evaluated by semiquantitative immunohistochemistry and Western blotting for HO-1 and HSP 70. These findings were correlated with terminal deoxynucleotidyltransferase-mediated 2'-deoxyuridine 5'-triphosphate-digoxigenin nick end labeling (TUNEL) staining and follow up. Compared to controls, MT and HSP 70 expression was significantly higher at zero hour. In contrast, HO-1 and the number of TUNEL-positive cells were not elevated. MT and HO-1 immunoexpression were inversely associated with graft function, and hence, were of prognostic relevance. MT and HSP 70 were sensitive to the duration of cold ischemia. MT and HO-1 are suitable indicators for tissue injury during ischemia and may serve as new predictive markers that need to be validated in further independent studies.
- Published
- 2006
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259. Robustness of the periodic and chaotic orientational behavior of tumbling nematic liquid crystals.
- Author
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Heidenreich S, Ilg P, and Hess S
- Abstract
The dynamical behavior of molecular alignment strongly affects physical properties of nematic liquid crystals. A theoretical description can be made by a nonlinear relaxation equation of the order parameter and leads to the prediction that rather complex even chaotic orientational behavior occur. Here the influence of fluctuating shear rates on the orientational dynamics especially on chaotic solutions is discussed. With the help of phase portraits and time evolution diagrams, we investigated the influence of different fluctuation strengths on the flow aligned, isotropic, and periodic solutions. To explore the effect of fluctuations on the chaotic behavior, we calculated the largest Lyapunov exponent for different fluctuation strengths. We found in all cases that small fluctuations of the shear rate do not affect the basic features of the dynamics of tumbling nematics. Furthermore, we present an amended potential modeling the isotropic to nematic transition and discuss the equivalence and difference to the commonly used Landau-de Gennes potential. In contrast to the Landau-de Gennes potential, our potential has the advantage to restrict the order parameter to physically admissible values. In the case of extensional flow, we show that the amended potential leads for increasing extensional rate to a better agreement with experimental results.
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- 2006
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260. [Ascites--only a symptom of liver disease?].
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Heidenreich S
- Subjects
- Aged, Albuminuria complications, Albuminuria diagnosis, Amyloidosis complications, Cardiomyopathies complications, Diagnosis, Differential, Electrocardiography, Female, Humans, Kidney Diseases complications, Proteinuria complications, Proteinuria diagnosis, Ultrasonography, Amyloidosis diagnosis, Ascites etiology, Cardiomyopathies diagnosis, Kidney Diseases diagnosis, Liver Diseases diagnosis
- Published
- 2006
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261. Attention, memory, and cognitive function in hepatic encephalopathy.
- Author
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Weissenborn K, Giewekemeyer K, Heidenreich S, Bokemeyer M, Berding G, and Ahl B
- Subjects
- Animals, Humans, Attention physiology, Cognition physiology, Hepatic Encephalopathy psychology, Memory physiology
- Abstract
Deficits in attention and arousal play a major role in the clinical presentation of hepatic encephalopathy. Attention deficits are also the main components of minimal hepatic encephalopathy. The present paper summarizes some findings about attentional and memory dysfunction in hepatic encephalopathy, with reference to basic knowledge about normal attention and memory function and their cerebral representation.
- Published
- 2005
- Full Text
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262. Long-term follow-up of double kidney transplantation using a score for evaluation of marginal donors*.
- Author
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Wolters HH, Palmes D, Heidenreich S, August C, Brockmann J, Senninger N, and Dietl KH
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- Acute Disease, Aged, Aged, 80 and over, Female, Follow-Up Studies, Graft Rejection epidemiology, Graft Survival, Humans, Incidence, Kidney physiopathology, Male, Middle Aged, Postoperative Period, Survival Analysis, Donor Selection, Kidney Transplantation methods, Tissue Donors
- Abstract
To face the problem of organ shortage, marginal grafts from 36 donors which had been refused for single transplantation were used for double-kidney transplantation (D-KTX). The residual kidney function was evaluated by the Muenster double kidney score. In a 5-year period kidneys from 57 marginal donors were transferred to our center. According to the Muenster double kidney score, the kidneys were distributed to single, double or refusal of transplantation. Sixteen male and 20 female donors were used for D-KTX (70+/-9.3 years, range 53-86). Thirty-six recipients (23 male, 13 female; 60.5+/-6.9 years) were double-grafted within a mean cold ischemic time of 19.3+/-3.4 h. Immunosuppression varied according to human leukocyte antigen (HLA)-mismatch. Graft and patient survival was observed up to 5 years. Initial graft function rate was 69%. Two recipients had a primary nonfunction (5.5%) and nine recipients suffered from delayed graft function (DGF; 25%). One-, 2-, 3-year creatinine values were 1.6 +/- 0.5, 1.9 +/- 0.6 and 2.2 +/- 0.7 mg/dl, respectively. One-, 2-, 3-, 4- and 5-year function rate was 93.7%, 93.5%, 81.8%, 76.4% and 55%, respectively (n = 32, 31, 22, 17 and 9). Acute rejection rate was 19%. 4 grafts were lost to chronic rejection (months 22, 25, 28, 48). Six (16%) died in long-term follow-up because of pneumonia (n = 2), carcinoma of the lung (n = 1), cardial complications (n = 2) and multiorgan failure (n = 1). D-KTX is a safe way to face the problem of organ shortage. However, a score for preoperative evaluation of marginal kidneys for single, dual or refusal of transplantation is essential.
- Published
- 2005
- Full Text
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263. Living donor kidney transplantation: impact of differentiated immunosuppressive regimen.
- Author
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Wolters HH, Heidenreich S, Dame C, Brockmann JG, Senninger N, and Krieglstein CF
- Subjects
- Drug Therapy, Combination, Family, Female, Follow-Up Studies, History, 16th Century, Humans, Immunosuppression Therapy methods, Living Donors, Middle Aged, Retrospective Studies, Immunosuppressive Agents therapeutic use, Kidney Transplantation immunology
- Abstract
Introduction: Recipients of related (R) and unrelated (NR) living donor kidney transplantations (LDKTX) receive immunosuppressive (IS) therapy 5 days in advance in order to achieve low rates of acute rejection episodes. We herein report the different IS regimens for R and NR transplants as well as acute rejection and primary function rates., Methods: Ninety-five LDKTX (69% R, 31% NR) were performed with mean cold ischemia time (CIT) of 145 +/- 32 minutes. In R-LDKTX mean age of recipients was 31 +/- 12.5 years. This cohort included 41 men and 25 women whose mean age was 50 +/- 11.1 years. The therapeutic regimen for R-LDKTX included CyA/MMF/prednisone; for NR-LDKTX, FK/MMF/prednisone. Among the recipients of NR grafts the mean recipient age was 51 +/- 8.5 years. This cohort included 23 men and 6 women whose donor mean age was 50 +/- 8.8 years. The mean HLA mismatch among R-LDKTX (2.3) was significantly less than that in the NR-LDKTX cohort (3.51)., Results: At a mean follow-up of 35 months, 94.7% of grafts were functioning. DGF was seen in only one recipient (1%). Three grafts were lost due to acute (R) or chronic (NR) rejection or to multiorgan failures. Two recipients died with functioning grafts. Biopsy-proven rejection episodes were observed in 17.2% of NR-LDKTX and 9% of R-LDKTX. In R-LDKTX 50% of rejection episodes were corticoid-sensitive, while 33% needed ATG, and 16% were treated by a switch to FK. In NR-LDKTX 20% of rejections were corticoid-sensitive, 40% needed ATG, and 40% were treated with rapamycin rescue therapy., Conclusion: Although HLA mismatching is significantly different between R- and NR-LDKTX, no difference in outcome was observed, which may be due to the specific therapeutic regimen and short CIT.
- Published
- 2005
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264. Heme-induced heme oxygenase-1 (HO-1) in human monocytes inhibits apoptosis despite caspase-3 up-regulation.
- Author
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Lang D, Reuter S, Buzescu T, August C, and Heidenreich S
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- Antigens, CD analysis, Antigens, CD metabolism, Apoptosis drug effects, B7-2 Antigen, Caspase 3, Cells, Cultured, Heme Oxygenase (Decyclizing) analysis, Heme Oxygenase (Decyclizing) genetics, Heme Oxygenase-1, Hemin pharmacology, Humans, Membrane Glycoproteins analysis, Membrane Glycoproteins metabolism, Membrane Proteins, Monocytes cytology, Monocytes drug effects, Proto-Oncogene Proteins c-bcl-2 analysis, Proto-Oncogene Proteins c-bcl-2 metabolism, Up-Regulation, fas Receptor analysis, fas Receptor metabolism, Apoptosis physiology, Caspases metabolism, Heme Oxygenase (Decyclizing) metabolism, Hemin physiology, Monocytes enzymology
- Abstract
Monocyte activation, apoptosis and differentiation are hallmarks of most inflammatory vascular disorders. We studied the effects of heme oxygenase-1 (HO-1) induced by its substrate hemin on apoptosis, caspase-3 expression and the differentiation of freshly isolated human monocytes. Hemin induced HO-1 in a dose- and time-dependent fashion as measured by semi-quantitative RT-PCR and flow cytometry. Apoptosis was markedly suppressed by hemin in cells rendered apoptotic by serum deprivation or dexamethasone as determined by flow cytometric detection of annexin V binding or transmission electron microscopy (TEM). The specific HO-1 inhibitor zinc protoporphyrin (ZnPP) reversed the effects of hemin on monocyte apoptosis and diminished cell lifespan. Surprisingly, the cytoprotective effects of hemin were positively correlated with caspase-3 up-regulation. Hemin-induced apoptosis suppression was enhanced by the caspase-3 inhibitor DEVD-CHO, indicating that caspase-3 was active in a pro-apoptotic fashion. Hemin inhibited CD95 as a putative cytoprotective mechanism. Morphological studies and detection of CD86 showed that monocytes differentiated into macrophages in response to hemin after relatively long incubation times, a phenomenon that might be provoked by caspase-3-regulated pathways. Our results confirm a similar cytoprotective effect of hemin/HO-1 for monocytes as has been shown for other cells, despite caspase-3 up-regulation. The fact that HO-1 may adversely affect monocyte survival and differentiation could be of particular significance in future therapies for occlusive vascular diseases or transplant rejection.
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- 2005
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265. [The patient with edema of the legs].
- Author
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Heidenreich S
- Subjects
- Acute Disease, Adult, Anti-Bacterial Agents administration & dosage, Anti-Bacterial Agents therapeutic use, Creatinine blood, Diagnosis, Differential, Diuretics administration & dosage, Diuretics therapeutic use, Drug Therapy, Combination, Edema classification, Edema diagnosis, Edema drug therapy, Female, Furosemide administration & dosage, Furosemide therapeutic use, Glomerulonephritis diagnosis, Glomerulonephritis drug therapy, Glomerulonephritis etiology, Humans, Influenza, Human complications, Kidney Diseases complications, Kidney Diseases diagnosis, Kidney Function Tests, Lymphedema diagnosis, Myxedema diagnosis, Penicillin G administration & dosage, Penicillin G therapeutic use, Phytotherapy, Potassium blood, Time Factors, Treatment Outcome, Edema etiology, Glomerulonephritis complications, Leg
- Published
- 2004
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266. [Primary loss of consciousness and amnesia in subarachnoid hemorrhage--a quantitative study].
- Author
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Lang CJ, Heidenreich SP, Fahlbusch R, and Neundörfer B
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- Adult, Age Factors, Aged, Aged, 80 and over, Amnesia psychology, Amnesia, Anterograde epidemiology, Amnesia, Anterograde etiology, Amnesia, Retrograde epidemiology, Amnesia, Retrograde etiology, Female, Follow-Up Studies, Humans, Male, Middle Aged, Sex Factors, Amnesia epidemiology, Amnesia etiology, Subarachnoid Hemorrhage complications, Unconsciousness epidemiology, Unconsciousness etiology
- Abstract
Subarachnoid hemorrhages (SAH) being sudden events affecting the brain in a rather wide-spread fashion are apt to induce loss of consciousness (LOC) and amnesia. The aim of the present study was to collect data on their frequency and extent. To this end we examined 48 patients at a mean of one year post-onset. Two thirds of them reported anterograde and an additional 17% retrograde amnesia; in 40% LOC (median 6 minutes) was observed. The durations were extremely skewed towards shorter times with a median of 2.7 days for anterograde and 1.3 days for retrograde amnesia who--with a single exception--were markedly shorter than anterograde amnesia. Summing up, a significant proportion of all SAH suffered LOC and amnesia occurred in the majority of cases. SAH therefore are events which with respect to LOC and amnesia bear some resemblance with closed head injuries. Exact observation and history taking may disclose important data on their severity and possible sequelae.
- Published
- 2004
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267. Memory function in early hepatic encephalopathy.
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Weissenborn K, Heidenreich S, Giewekemeyer K, Rückert N, and Hecker H
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- Adolescent, Adult, Aged, Humans, Learning, Memory, Short-Term, Mental Recall, Middle Aged, Pattern Recognition, Visual, Hepatic Encephalopathy psychology, Memory
- Abstract
Background: Early hepatic encephalopathy (HE) is characterized by deficits in motor performance, visual perception, visuo-constructive abilities and attention. Whether defective memory is a feature of early HE is controversial., Aims: To analyze memory function in patients with early HE., Methods: Memory tests were applied to cirrhotic patients with grade 0 HE, minimal HE and grade I HE (n=45) and controls (n=52). The battery included short and long term memory tests requiring free recall or recognition. Minimal HE was diagnosed by assessing the psychometric hepatic encephalopathy score using the PSE-Syndrom-Test and by carrying out a neurological examination. Group differences of the test results were analyzed using analysis of covariance., Results: HE 0 patients achieved test results similar to the controls in all but two tests. Patients with early HE (minimal and grade I HE) scored lower than the controls in all tests applied. A detailed analysis of test performance showed that the patients' deficits were in attention and visual perception, rather than memory., Conclusions: Patients with early HE score lower than controls in memory tasks predominantly because of deficits in attention and visual perception.
- Published
- 2003
- Full Text
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268. Expanding the donor pool using marginal organs: single-center experience with 36 double-kidney transplantations in 5 years.
- Author
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Wolters HH, Vowinkel T, Heidenreich S, Brockmann J, August C, Krieglstein CF, Senninger N, and Dietl KH
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- Humans, Immunosuppression Therapy methods, Kidney Transplantation immunology, Retrospective Studies, Time Factors, Tissue Donors statistics & numerical data, Treatment Failure, Treatment Outcome, Graft Survival physiology, Kidney Transplantation statistics & numerical data, Tissue Donors supply & distribution
- Published
- 2003
- Full Text
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269. Living donor kidney transplantation: chance for the recipient--financial risk for the donor?
- Author
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Wolters HH, Heidenreich S, and Senninger N
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- Follow-Up Studies, Graft Rejection epidemiology, Humans, Retrospective Studies, Risk Factors, Surveys and Questionnaires, Time Factors, Treatment Outcome, Hepatectomy adverse effects, Kidney Transplantation physiology, Living Donors, Tissue and Organ Harvesting adverse effects
- Abstract
Background: With living donation, in addition to the medical risk, the financial risk for the donor is essential, especially in case of complications that potentially can led to disability and loss of work. We report the experiences of those who have donated a kidney in our transplant center., Methods: We contacted 80 donors who donated a kidney at least 6 months prior to evaluation: 72% answered 33 questions. [mean age: 54 +/- 10 (33-75) years; 69% living related, 31% unrelated]., Results: Of the 80 donors contacted, 91% (53) reported to have no financial expenses due to donation; 9% (5) had expenses, but only few of them clarified exact amount. One donor had to borrow money to cover the lack when he was unable to perform his job. Another claimed the disparity between normal salary and payment from insurance company as a financial expense. Evaluation procedure prior to donation was organized variously: some donors were on holiday while evaluated, some officially were ill, others had to take off some days without payment. None of the donors lost his or her job due to donation., Conclusion: The financial risk of living donation is theoretically well covered by different insurances. However, some of the donors had to cover some expenses by themselves. Fortunately, so far in our center no major complications occurred and all donors went home in good health after donation. If costs are covered when a healthy donor loses his or her ability to work due to donation remains unclear since no donor has experienced this problem.
- Published
- 2003
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270. Calcineurin-free protocols with basiliximab induction allow patients included in "old to old" programs achieve standard kidney transplant function.
- Author
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Emparan C, Laukötter M, Wolters H, Dame C, Heidenreich S, and Senninger N
- Subjects
- Adrenal Cortex Hormones therapeutic use, Age Factors, Basiliximab, Creatinine blood, Cyclosporine therapeutic use, Drug Therapy, Combination, Humans, Kidney Transplantation immunology, Middle Aged, Mycophenolic Acid therapeutic use, Tissue Donors statistics & numerical data, Antibodies, Monoclonal therapeutic use, Calcineurin physiology, Immunosuppressive Agents therapeutic use, Kidney Transplantation physiology, Mycophenolic Acid analogs & derivatives, Recombinant Fusion Proteins
- Abstract
Introduction: The EuroTransplant "old to old" program establishes that patients older than 60 years can receive offers of organs from donors older than 60 years. The compromised function of these organs makes it a priority to preserve their initial kidney function., Hypothesis: Calcineurin-sparing protocols using anti-IL-2 receptor (IL-2R) antibody induction (Simulect) may benefit initial kidney function in these patients, as assessed by the rates of delayed graft function and of rejection during the first month after transplant., Patients and Methods: A cohort of 15 consecutive elderly patients were prospectively compared with 30 cadaveric kidney transplants in younger recipients. Study patients were induced with Simulect (20 mg, 30 minutes before reperfusion and 4 days after transplantation) and steroids, delaying the introduction of CsA until the serum creatinine was below 3 mg/dL. The other cohort of patients were immunosuppressed with tacrolimus (trough 8 to 12), mycophenolats mofetil (MMF, 1 g/d), and an identical taper of steroids. The analysis compared donor and recipient ages, mean cold ischemic time, incidence of initial kidney function (diuresis in the first 24 h) serum creatinine levels, glomerular filtration rate (GFR), number of dialysis sessions, and rejection rate in the two groups., Results: Except for the donor and recipient ages (72 vs 54 in donors, and 67 versus 52 years in recipients), no significant differences were observed between the groups among the rates of acute rejection (6.6% vs 13.2%), delayed graft function (13.2% required dialysis), or infection (6.6%). Within 1 month all 45 grafts showed primary function with equal creatinine levels (mean 1.65)., Conclusions: Calcineurin-free protocols using IL-2 therapy as the initial suppression allow patients in the "old to old" ET program to display equal results to cadaveric kidney transplants with initial treatment with calcineurin antagonists.
- Published
- 2003
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271. Arterial hypertension and ischaemic stroke.
- Author
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Droste DW, Ritter MA, Dittrich R, Heidenreich S, Wichter T, Freund M, and Ringelstein EB
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- Angiotensin Receptor Antagonists, Angiotensin-Converting Enzyme Inhibitors therapeutic use, Antihypertensive Agents adverse effects, Brain Infarction prevention & control, Brain Ischemia etiology, Humans, Hydroxymethylglutaryl-CoA Reductase Inhibitors therapeutic use, Risk Factors, Antihypertensive Agents therapeutic use, Brain Infarction etiology, Brain Ischemia complications, Hypertension complications, Hypertension drug therapy
- Abstract
Objectives: Arterial hypertension is, besides age, the number one risk factor for ischaemic stroke. Patients with arterial hypertension frequently present with additional coexisting vascular risk factors interacting in a complex way., Material and Methods: This paper reviews the benefit of antihypertensive treatment, as well as different treatment options of arterial hypertension and their side-effects., Results: Patients with definite arterial hypertension, but also patients with so-called normal or high-normal blood pressure are at increased risk to develop stroke and other cardiovascular complications. Vascular remodelling of small and large vessels provoked by arterial hypertension is the initial step in the development of atherosclerosis and lipohyalinosis. Vascular remodelling can be improved or even normalized by antihypertensive treatment with angiotensin-converting-enzyme inhibitors and angiotensin-I-receptor antagonists showing the most convincing effects. Angiotensin-converting-enzyme inhibitors and angiotensin-I-receptor antagonists have the lowest rate of side-effects, however, economic restraints hinder their general application. Statins are needed to treat dyslipidaemia. They also lower blood pressure and have a synergistic effect with the above two antihypertensive components in lowering blood pressure. In hypertensive patients, risk of stroke and other cardiovascular complications is determined by the blood pressure level and the presence or absence of target organ damage and the interaction with other risk factors, such as cigarette smoking, dyslipidaemia, and diabetes. These high-risk patients should be treated even more aggressively than usual., Conclusions: In the vast majority of patients and healthy individuals, target blood pressure should be as high as or below 120/80 mmHg to minimize the occurrence of stroke and other cardiovascular complications.
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- 2003
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272. Outcome of kidney transplantation in patients with inherited thrombophilia: data of a prospective study.
- Author
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Heidenreich S, Junker R, Wolters H, Lang D, Hessing S, Nitsche G, and Nowak-Göttl U
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- Adult, Factor V genetics, Female, Genotype, Graft Rejection etiology, Graft Survival, Heterozygote, Humans, Male, Methylenetetrahydrofolate Reductase (NADPH2), Middle Aged, Mutation, Oxidoreductases Acting on CH-NH Group Donors genetics, Point Mutation, Prospective Studies, Prothrombin genetics, Thrombophilia complications, Time Factors, Transplantation, Homologous, Treatment Outcome, Kidney Transplantation, Thrombophilia genetics
- Abstract
Inherited prothrombotic risk factors predispose patients to thromboembolic events. In kidney transplant recipients, thrombophilia may manifest itself with venous thrombosis, microvascular occlusion, or acute rejection with major consequences for allograft survival. This is a prospective study on 165 renal allograft recipients to evaluate the contribution of genetic thrombophilic risk factors to transplant outcome. Besides antithrombin, protein C, and protein S deficiencies, none of which was found in our patient group, factor V G1691A (FV G1691A), prothrombin G20210A (PT G20210A) mutations, and methylenetetrahydrofolate reductase (MTHFR) gene C677T polymorphisms were studied. The primary endpoint of the study was occurrence of an acute rejection within the first 90 d and transplant loss within 1 yr. Heterozygous FV G1691A and PT G20210A mutations and the MTHFR T677T variant were significantly associated with acute rejections with rejection rates of 68%, 67%, and 71%, respectively, as compared with 35% in patients not carrying these genotypes. Many rejections that were histologically proven were acute vascular ones. Transplant loss was significantly associated exclusively with the PT G20210A group (50% 1-yr graft survival; odds ratio, 10.0; 95% confidence interval, 1.8 to 56.1). PT G20210A patients exerted the highest prothrombotic activity pretransplant, as determined by prothrombin 1.2 fragments (PT F1.2), which may be the background for minor outcome. In conclusion, common prothrombotic mutations are significantly associated with acute rejections, especially vascular rejections, and for PT G20210A also with early transplant failure. Screening for hypercoagulable states pretransplant is recommended to intensify anticoagulatory treatment posttransplant.
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- 2003
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273. Protein kinase C (PKC) dependent induction of tissue factor (TF) by mesangial cells in response to inflammatory mediators and release during apoptosis.
- Author
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Lang D, Terstesse M, Dohle F, Bangen P, Banas B, Pauels HG, and Heidenreich S
- Subjects
- Calcium metabolism, Cell Line, Cells, Cultured, Chelating Agents pharmacology, Cyclic AMP-Dependent Protein Kinases antagonists & inhibitors, Cyclic AMP-Dependent Protein Kinases metabolism, Dose-Response Relationship, Drug, Egtazic Acid pharmacology, Enzyme Inhibitors pharmacology, Enzyme-Linked Immunosorbent Assay, Gene Expression Regulation drug effects, Glomerular Mesangium cytology, Glomerular Mesangium metabolism, Humans, Hydrogen Peroxide pharmacology, Indoles pharmacology, Interleukin-1 pharmacology, Lipopolysaccharides pharmacology, Naphthalenes pharmacology, Protein Kinase C antagonists & inhibitors, Pyrroles pharmacology, RNA, Messenger drug effects, RNA, Messenger genetics, RNA, Messenger metabolism, Reverse Transcriptase Polymerase Chain Reaction, Thromboplastin metabolism, Time Factors, Tumor Necrosis Factor-alpha pharmacology, Apoptosis, Carbazoles, Egtazic Acid analogs & derivatives, Glomerular Mesangium drug effects, Inflammation Mediators pharmacology, Protein Kinase C metabolism, Thromboplastin genetics
- Abstract
1. In inflammatory kidney diseases procoagulatory activity (PCA) becomes evident. Glomerular fibrin deposits and capillary microthrombi are histopathological hallmarks in most forms of glomerulonephritis. 2. Therefore in this study the expression of tissue factor (TF) as the main inducer of thrombogenesis was examined in cultured human mesangial cells (MC) in response to proinflammatory stimuli such as interleukin-1 (IL-1 beta), tumour necrosis factor alpha (TNF-alpha) and lipopolysaccharide (LPS). Also main signalling pathways were investigated. 3. IL-1 beta, TNF-alpha and LPS induced TF in MC in a time and dose dependent manner on mRNA and protein levels. Highest activity was found after 12 h of stimulation. Induction of TF was completely blockable by BAPTA-AM, a chelator of intracellular [Ca(2+)](i) as well as calphostin, a protein kinase C (PKC) inhibitor. Activation of the protein kinase A (PKA) pathway had no influence on basal TF expression, but down-regulated cytokine-induced TF. The PKA blocker, KT5720, increased TF formation significantly. Since TF exerts its activity primarily on the surface of cells and after release of encrypted receptors we further tested TF activity in MC supernatants. IL-1 beta did not significantly increase TF activity in supernatants of intact cells. However, when MC were rendered apoptotic by oxidative metabolites, IL-1 beta treated MC released highly stimulated TF activity into the supernatants, suggesting that a paracrine activation of the coagulatory cascade can take place under such conditions. 4. Inflammatory mediators up-regulate TF expression in MC by a PKC dependent pathway whereas PKA can serve as a negative feed-back link. Apoptosis of inflammatory MC may trigger to spread PCA.
- Published
- 2002
- Full Text
- View/download PDF
274. Acute renal failure in IgA nephropathy: aggravation by gross hematuria due to anticoagulant treatment.
- Author
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August C, Atzeni A, Köster L, Heidenreich S, and Lang D
- Subjects
- Acute Kidney Injury therapy, Anticoagulants therapeutic use, Biopsy, Needle, Female, Follow-Up Studies, Glomerulonephritis, IGA complications, Hematuria physiopathology, Humans, Immunohistochemistry, Middle Aged, Renal Dialysis methods, Risk Assessment, Severity of Illness Index, Treatment Outcome, Venous Thrombosis complications, Acute Kidney Injury chemically induced, Anticoagulants adverse effects, Glomerulonephritis, IGA pathology, Hematuria chemically induced, Venous Thrombosis drug therapy
- Abstract
IgA nephropathy is one of the most common forms of glomerulonephritis. Macroscopic or microscopic hematuria with mild proteinuria are the main symptoms. Without complicating factors, IgA nephropathy has a favourable long-term prognosis. We report a case of reversible acute renal failure (ARF) as a complication of mild IgA nephropathy while oral anticoagulants were administered. Diagnosis was based on a renal biopsy showing marked granular mesangial IgA-deposition. In addition, numerous tubules were extended and completely obstructed by red blood cell casts. After hemodialysis treatment and parallel anti-inflammatory steroids and after stopping anticoagulation, renal function gradually improved up to complete remission. This report indicates that anticoagulatory treatment may have negative effects on the long-term prognosis of IgA nephropathy with respect to development of ARF or tubulo-interstitial inflammation.
- Published
- 2002
275. End-stage liver and kidney disease: results of combined transplantation.
- Author
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Vowinkel T, Wolters HH, Brockmann J, Vogel T, Stähle D, Heidenreich S, Menzel J, Senninger N, and Dietl KH
- Subjects
- Female, Follow-Up Studies, Humans, Kidney Failure, Chronic complications, Liver Failure complications, Male, Retrospective Studies, Time Factors, Treatment Outcome, Graft Survival physiology, Hepatorenal Syndrome surgery, Kidney Failure, Chronic surgery, Kidney Transplantation methods, Liver Failure surgery, Liver Transplantation methods
- Published
- 2002
- Full Text
- View/download PDF
276. Living donor renal transplantation--experience with 50 patients in 5 years.
- Author
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Wolters HH, Vowinkel T, Brockmann J, Palmes D, Heidenreich S, and Dietl KH
- Subjects
- Drug Therapy, Combination, Female, Humans, Immunosuppressive Agents therapeutic use, Kidney Transplantation immunology, Male, Nephrectomy methods, Nuclear Family, Organ Preservation methods, Postoperative Complications classification, Postoperative Complications epidemiology, Retrospective Studies, Surgical Wound Infection epidemiology, Time Factors, Tissue and Organ Harvesting methods, Treatment Outcome, Graft Survival physiology, Kidney, Kidney Transplantation physiology, Living Donors statistics & numerical data
- Published
- 2002
- Full Text
- View/download PDF
277. Down-regulation of monocyte apoptosis by phagocytosis of platelets: involvement of a caspase-9, caspase-3, and heat shock protein 70-dependent pathway.
- Author
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Lang D, Dohle F, Terstesse M, Bangen P, August C, Pauels HG, and Heidenreich S
- Subjects
- Caspase 3, Caspase 9, Caspase Inhibitors, Cells, Cultured, Coculture Techniques, Growth Substances physiology, HSP70 Heat-Shock Proteins antagonists & inhibitors, HSP70 Heat-Shock Proteins biosynthesis, Humans, Monocytes cytology, Monocytes enzymology, Platelet Activation immunology, Up-Regulation immunology, Apoptosis immunology, Blood Platelets immunology, Caspases physiology, Down-Regulation immunology, HSP70 Heat-Shock Proteins physiology, Monocytes immunology, Phagocytosis immunology, Signal Transduction immunology
- Abstract
Monocytes interact and cross-talk with platelets in many settings including inflammation, hemostasis, or vascular disorders. During inflammatory diseases, there is a rapid targeting of monocytes and platelets to points of inflammation and endothelial injury, where they lie side-by-side. In this in vitro study, we investigated different interactions between monocytes and platelets and elucidated whether platelets might affect monocyte apoptosis. Freshly isolated human monocytes were rendered apoptotic by serum deprivation or CD95 ligation and cocultured with platelets. Monocyte apoptosis was determined by flow cytometry, TUNEL staining, DNA electrophoresis, and transmission electron microscopy imaging. We could show that monocyte apoptosis was highly suppressed when platelets were added to the cultures. Transmission electron microscopy depicted that monocytes completely ingested thrombocytes by phagocytosis. Blocking thrombocyte uptake by the phagocytosis inhibitor cytochalasin D abrogated the enhanced monocyte survival and led to high apoptosis levels. Monocyte survival was paralleled by down-regulation of caspase-9 and -3 and up-regulation of heat shock protein 70 during uptake of platelets. Platelet supernatants and contents of platelet granules were ineffective in altering monocyte senescence. Also, ingestion of latex beads or zymosan by monocytes was ineffective to mimic platelet-dependent rescue from apoptosis. In conclusion, this study shows that platelets can suppress apoptosis of monocytes by a specific phagocytosis-dependent process with further consequences for atherosclerotic or inflammatory conditions.
- Published
- 2002
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278. Fibromuscular dysplasia in a living donor: early post-operative allograft artery stenosis with successful venous interposition.
- Author
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Wolters HH, Vowinkel T, Schult M, Heidenreich S, Senninger N, and Dietl KH
- Subjects
- Adult, Aged, Female, Humans, Male, Tissue Donors, Transplantation, Homologous, Fibromuscular Dysplasia etiology, Kidney Transplantation adverse effects, Renal Artery Obstruction etiology
- Published
- 2002
- Full Text
- View/download PDF
279. The anastomosis between renal polar arteries and arteria epigastrica inferior in kidney transplantation: an option to decrease the risk of ureter necrosis?
- Author
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Wolters HH, Schult M, Heidenreich S, Chariat M, Senninger N, and Dietl KH
- Subjects
- Humans, Middle Aged, Necrosis, Anastomosis, Surgical, Epigastric Arteries surgery, Kidney Transplantation methods, Renal Artery surgery, Ureter pathology
- Abstract
Ureteral necrosis after renal transplantation is often the result of impaired perfusion due to loss of donor polar arteries. A way of preserving polar arteries is their anastomosis with the A. epigastrica inferior. In three cases (aged 49-, 58-, and 63 years), 9.3 % of 33 living donors, we detected donor polar arteries on both sides, and anastomosed the polar artery to the A. epigastrica inferior with microsurgical methods. Intraoperatively, the flow was measured by flowmeter, in the postoperative course duplexsonography and MR-angiography was performed. In all three cases we noted a bluish, ischemic parenchym mass of 10-25 % of the kidney and ureter. It recovered immediately, however, after the polar artery had been reconstructed. Intraoperative measurement showed a high flow on the polar- and the main renal artery. Duplexsonography and MR-angiography documented a good flow on the A. epigastrica anastomosis. There have been no signs of ureteral problems at all. After a mean follow-up time of 26 months, the mean creatinine level is 1.46 mg/ml. Ureteral necrosis after kidney transplantation is mostly the result of a lack of perfusion of the polar arteries of the lower kidney pole. If arteriosclerotic lesions inhibit an anastomosis with the renal artery, the anastomosis with the A. epigastrica inferior seems to be a useful alternative.
- Published
- 2001
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280. Attention deficits in minimal hepatic encephalopathy.
- Author
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Weissenborn K, Heidenreich S, Ennen J, Rückert N, and Hecker H
- Subjects
- Adult, Aged, Humans, Liver Cirrhosis complications, Memory, Middle Aged, Motor Skills, Neuropsychological Tests, Psychometrics, Attention, Cognition Disorders etiology, Hepatic Encephalopathy complications
- Abstract
Minimal hepatic encephalopathy (HE) is characterized by a decrease of psychomotor speed, and deficits in visual perception, visuo-spatial orientation, and visuo-constructive abilities. Attention deficits have also been proposed to be part of the syndrome. Several attempts were made in the past to elaborate suitable psychometric means for the assessment of minimal HE. However, there is still no "gold standard" for the diagnosis of minimal HE. We recently evaluated the so called "PSE-Test" for the assessment of minimal HE, a test battery which does not include a test predominantly aimed at the assessment of attention. We therefore presented a battery of attention tests in addition to the PSE-Test to a group of cirrhotics without clinical signs of HE compared to a healthy control group matched for age and education to determine whether the addition of special attention tests would increase the diagnostic sensitivity of the PSE-Test. It was shown that the patients with a pathological PSE-Test result differed significantly from controls in all attention tests applied, while the patients with normal PSE-Test results achieved attention test results similar to that of the controls. Thus, the PSE-Test results represent attention deficits as well as deficits in motor skills, visuo-spatial orientation, and visual construction.
- Published
- 2001
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281. Differential expression of heat shock protein 70 (hsp70) in human monocytes rendered apoptotic by IL-4 or serum deprivation.
- Author
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Lang D, Hubrich A, Dohle F, Terstesse M, Saleh H, Schmidt M, Pauels HG, and Heidenreich S
- Subjects
- Antibodies pharmacology, Apoptosis drug effects, Cell Survival drug effects, Cell Survival physiology, Culture Media, Serum-Free, Dose-Response Relationship, Drug, HSP70 Heat-Shock Proteins physiology, Heat-Shock Response drug effects, Heat-Shock Response physiology, Humans, Interleukin-4 immunology, Kinetics, Lipopolysaccharides pharmacology, Monocytes cytology, Monocytes drug effects, Apoptosis physiology, HSP70 Heat-Shock Proteins biosynthesis, Interleukin-4 pharmacology, Monocytes metabolism
- Abstract
Apoptosis of monocytes is regulated by the balance between pro- and antiapoptotic triggers and pathways and may strongly influence inflammatory disorders. The major heat shock protein, hsp70, is an effective inhibitor of apoptosis in lymphocytic and monocytic tumor cell lines, but the implications in the regulation of apoptosis of freshly isolated human monocytes have not been elucidated. In this study, we examined whether two different triggers of monocyte apoptosis, serum deprivation and IL-4, respectively, altered hsp70 expression and whether expression levels correlated with monocyte survival. Monocyte apoptosis was determined quantitatively by flow cytometry detecting annexin V binding or nuclear stainability with propidium iodide (PI). Hsp70 expression was analyzed by semiquantitative RT-PCR and immunoblotting. Exposing monocytes to heat shock (47 degrees C, 20 min) induced a rapid and marked upregulation of hsp70 without evoking injury or apoptosis, suggesting that hsp70 conferred protection and survival. In accordance, when monocytes were rendered apoptotic by serum deprivation, a drastic downregulation of hsp70 occurred, which was accompanied by a reduced synthesis of the constitutive family member hsc70. However, induction of monocyte apoptosis by IL-4 increased hsp70 expression in a concentration and time-dependent fashion. A neutralizing antibody against IL-4 abolished hsp70 expression and apoptosis induction after IL-4 treatment and so excluded indirect effects. LPS rescued monocytes from apoptosis but did not alter hsp70 formation significantly. These findings suggest that, in monocytes, distinct apoptotic triggers induce different responses of hsp70 so that this molecule does not exert protection against cell death directly or in general.
- Published
- 2000
282. Regulation of mesangial cell apoptosis and proliferation by intracellular Ca(2+) signals.
- Author
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Saleh H, Schlatter E, Lang D, Pauels HG, and Heidenreich S
- Subjects
- Animals, Apoptosis drug effects, Buffers, Calcium metabolism, Cell Division drug effects, Cell Division physiology, Chelating Agents pharmacology, Egtazic Acid pharmacology, Enzyme Inhibitors pharmacology, Glomerular Mesangium cytology, Glomerular Mesangium drug effects, Intracellular Membranes metabolism, Male, Osmolar Concentration, Platelet-Derived Growth Factor pharmacology, Rats, Rats, Sprague-Dawley, Thapsigargin pharmacology, Apoptosis physiology, Calcium Signaling physiology, Egtazic Acid analogs & derivatives, Glomerular Mesangium physiology, Intracellular Membranes physiology
- Abstract
Background: In inflammatory glomerular diseases, proliferation, as well as apoptosis of mesangial cells (MCs), has been shown histomorphologically. Both processes may regulate the cellular content of the mesangium by closely influencing each other. In the present study, we examined whether the cytoplasmic free Ca(2+) concentration [Ca(2+)](i) is involved as a key second messenger in the regulation of proliferative and apoptotic events., Methods: Thapsigargin, an inhibitor of the endoplasmic Ca(2+)-Mg(2+)-ATPase, was used as a test substance to investigate the role of [Ca(2+)](i) in signaling MC apoptosis and growth in vitro. Apoptosis was determined by nuclear chromatin staining with Hoechst 33258, by a [3H]-thymidine-based DNA fragmentation assay or by flow cytometry detecting binding of FITC-conjugated annexin V. Proliferation was measured by [3H]-thymidine incorporation into acid-precipitable material and corroborated by cell counting., Results: Thapsigargin significantly induced apoptosis and inhibited proliferation dose dependently in nanomolar concentrations without evoking necrotic damage when administered not longer than 12 hours. Significant apoptosis was measurable after a six-hour treatment of MCs with thapsigargin. Determination of [Ca(2+)](i) by fura-2-dependent spectrofluorometry showed that thapsigargin was able to induce prolonged [Ca(2+)](i) rises that could be prevented by preincubation with the intracellular Ca(2+) chelator 1, 2-bis(2-aminophenoxy)-ethane-N,N,N', N'-tetra-acetic acid (BAPTA) acetomethyl ester (AM). BAPTA had no influence on MC viability but reversed thapsigargin-induced apoptosis to control levels. After thapsigargin treatment (100 nmol/L, 12 hours), apoptotic MCs had a significantly higher [Ca(2+)](i) of 251 +/- 25 nmol/L (N = 41) as compared with MCs that were not or not yet apoptotic ([Ca(2+)](i) of 116 +/- 20 nmol/L, N = 26, P < 0,05). Platelet-derived growth factor (PDGF), a well-characterized growth factor for MCs, reversed the effects of thapsigargin on proliferation and apoptosis in a similar fashion as BAPTA. PDGF acutely stimulated increases of [Ca2+]i but abolished thapsigargin-dependent, but not angiotensin II- or ATP-induced Ca(2+) rises when administered during a 12-hour preincubation., Conclusions: Our data suggest that a sustained increase of [Ca(2+)](i) may serve as a signal to trigger MC apoptosis. Growth factors such as PDGF can abolish apoptosis induced by elevations of [Ca(2+)](i) by altering intracellular Ca(2+) signaling.
- Published
- 2000
- Full Text
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283. Cadaveric "two-in-one" kidney transplantation from marginal donors: experience of 26 cases after 3 years.
- Author
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Dietl KH, Wolters H, Marschall B, Senninger N, and Heidenreich S
- Subjects
- Aged, Creatinine blood, Graft Rejection prevention & control, Graft Survival, Humans, Hypertension epidemiology, Kidney Transplantation immunology, Middle Aged, Prevalence, Time Factors, Tissue Donors, Kidney Transplantation methods
- Abstract
Background: Because of the problem of organ shortage, the use of renal transplants from marginal donors has been tested by different procedures., Methods: In our center 26 recipients (59 +/- 7 years) underwent double renal transplantation from July 1996 to August 1999 using marginal donors (71 +/- 6 years). A special scoring was applied that included donor age, serum creatinine, the grade of glomerulosclerosis, and kidney weights leading to the decision whether single or dual or no kidney transplantation was performed., Results: After an average follow-up of 18 +/- 10 months 22 of 26 (85%) double kidney transplant recipients are alive and have functioning grafts. Three patients died with well-functioning grafts. The actuarial 1-year patient and graft survival rate was 94% (n=18), the 2-year rate 92% (n=12). Two patients lost one graft each without becoming dialysis dependent. The average serum creatinine was 1.6 +/- 0.5 mg/dl after 12 months (n=17) and 1.9 +/- 0.6 mg/dl after 24 months (n=11). Primary nonfunction occurred in 31%, acute rejection within the first 6 months in 14%. Ten patients who received single old grafts according to our score had similar transplant survival rates but worse graft function after 1 year., Conclusions: Transplant function and survival of patients after dual kidney transplantation indicate that this procedure is reasonable to ameliorate the problem of organ shortage. The most crucial point is to establish a widely accepted standardized scoring for the donors leading to single, dual, or refusal of transplantation.
- Published
- 2000
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284. [Long-term problems after kidney transplantations].
- Author
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Heidenreich S, August C, and Lang D
- Subjects
- Age Factors, Chronic Disease, Humans, Hyperlipidemias prevention & control, Hypertension prevention & control, Risk Factors, Secondary Prevention, Graft Rejection physiopathology, Immunosuppressive Agents adverse effects, Kidney Failure, Chronic surgery, Kidney Transplantation adverse effects, Postoperative Complications physiopathology, Postoperative Complications prevention & control
- Abstract
Allogenic kidney transplantation is a widely established treatment option for patients with end-stage renal disease to gain independency from dialysis and recovery of excretory and hormonal functions. Transplantation is superior to dialysis with respect to quality of life, morbidity and mortality. Improvements in one-year graft survival have become evident during the last decades, but long-term outcome is not yet satisfying. The most common form of late transplant failure is chronic rejection or chronic allograft nephropathy, and as a consequence of higher ages of transplant recipients death of patients with functioning grafts. The histological hallmark of chronic rejection is intimal thickening of small arteries and arterioles, but the involved pathomechanisms are not well understood. Strict normalization of blood pressure and hyperlipidemia by drugs aims to prevent vascular alterations of chronic allograft nephropathy. In addition, in this overview some other late complications of renal transplant recipients are addressed which are associated to chronic immunosuppression, such as viral or malignant diseases.
- Published
- 2000
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285. Pulmonary manifestation of systemic mast cell disease.
- Author
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Schmidt M, Dercken C, Loke O, Reimann S, Diederich S, Blasius S, and Heidenreich S
- Subjects
- Humans, Male, Middle Aged, Lung Diseases etiology, Lung Diseases pathology, Mastocytosis complications
- Abstract
Systemic mast cell disease is a rare disease of unknown aetiology. Systemic infiltration and proliferation of mast cells in skin, bone marrow, gastrointestinum and lymph nodes is the central pathological feature. This study reports a patient with mastocytosis of the skin (urticaria pigmentosa) for 10 yrs. The patient was referred to hospital for dyspnoea. Chest radiograph showed moderate reticular infiltration of both lungs, computerized tomography revealed multiple lymph nodes of the mediastinum and faint nodular lesions of middle and upper areas of lungs. Transbronchial biopsy demonstrated mast cell infiltration of the lung with formation of mast cell granuloma. According to the current literature, systemic mast cell disease with pulmonary involvement is a very rare entity. After a treatment with interferon alpha-2a over 6 months, the patient's condition and particularly dyspnoea showed improvement in parallel with an amelioration of the lesions as demonstrated by thorax computed tomography.
- Published
- 2000
- Full Text
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286. Hypercoagulable state and graft rejection--is there a link?
- Author
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Heidenreich S, Nowak-Göttl U, and August C
- Subjects
- Humans, Immunosuppression Therapy adverse effects, Kidney Failure, Chronic blood, Virus Diseases complications, Graft Rejection etiology, Thrombophilia complications, Thrombophilia etiology
- Published
- 1999
- Full Text
- View/download PDF
287. Tyrosine phosphorylation in peripheral T cells of kidney transplant recipients: analyses of baseline levels and response to T cell receptor stimulation.
- Author
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Müller C, Bonmann M, Heidenreich S, Kiehl MG, and Koch OM
- Subjects
- Adult, Aged, Antibodies, Monoclonal pharmacology, CD3 Complex biosynthesis, Female, Humans, Male, Middle Aged, Phosphorylation, Phosphotyrosine metabolism, Receptors, Antigen, T-Cell drug effects, Receptors, Antigen, T-Cell metabolism, T-Lymphocytes immunology, Kidney Transplantation, T-Lymphocytes metabolism, Tyrosine metabolism
- Abstract
Impaired immunosurveillance in recipients of organ transplants has been attributed to alleviation of T cell functions. We analyzed the phosphorylation of tyrosine residues in T cells of peripheral blood, and after T cell receptor (TCR) stimulation. The TCR was stimulated by OKT3 monoclonal antibody (mAb) in non-separated heparinized blood specimens of patients (n=64) and healthy controls (n=25). After fixation and red cell lysis, lymphocytes were permeabilized by saponin. Subsequently, intracellular phosphotyrosine residues and surface CD3 antigen were stained simultaneously with specific mAbs. We analyzed transplant recipients and healthy donors for baseline levels of total cellular tyrosine phosphorylation and for increase in phosphotyrosine content following stimulation by OKT3. Phosphotyrosine levels were significantly lower in non-stimulated T cells of kidney transplant recipients compared to controls (p=0.004). There was a marked variability in the levels of tyrosine phosphorylation among transplanted patients (p=0.02). T cell receptor stimulation by OKT3 mAb in vitro led to a strong increase of tyrosine phosphorylation in all specimens of patients and healthy controls. In conclusion, we demonstrated decreased phosphotyrosine levels in T cells of kidney transplant recipients compared to healthy donors. However, increase in tyrosine phosphorylation was not impaired in all patients as a result of TCR stimulation.
- Published
- 1999
- Full Text
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288. Monocyte CD14: a multifunctional receptor engaged in apoptosis from both sides.
- Author
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Heidenreich S
- Subjects
- Apoptosis immunology, Humans, Lipopolysaccharide Receptors blood, Monocytes immunology
- Abstract
Like all other immune system cells, monocytes and macrophages may undergo apoptotic cell death in response to specific triggers and mediators or as a consequence of aging. However, factors inducing apoptosis and the involved cellular and molecular mechanisms are much better investigated and understood for lymphocytes. Th2 cell-derived cytokines such as interleukin-4 (IL-4) are able to induce monocyte apoptosis most effectively. This process is preceded by down-regulation of the CD14 surface receptor. Mediators such as lipopolysaccharide (LPS) suppress and postpone apoptosis in parallel with up-regulation of CD14. Macrophages are rather resistant against apoptotic damage, and factors able to evoke apoptosis in monocytes are often ineffective in macrophages. Resistance of macrophages against apoptotic triggers may be beneficial for inflammatory processes where macrophages are engaged and needed as phagocytes for ingestion and removal of moribund cells. The multifunctional CD14 receptor of monocytes/macrophages is supposed to be involved in the apoptotic network on both sides: as a surface molecule of monocytes that can promote survival and antagonize apoptosis and as a recognition receptor of macrophages that enables or supports interaction with apoptotic cells.
- Published
- 1999
- Full Text
- View/download PDF
289. How to assess glomerular function and damage in humans.
- Author
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Rahn KH, Heidenreich S, and Brückner D
- Subjects
- Humans, Kidney Diseases physiopathology, Kidney Function Tests, Kidney Glomerulus physiopathology
- Abstract
In human subjects, the assessment of renal function and of its changes by interventions is limited to the measurement of glomerular filtration rate (GFR), renal blood flow and the estimation of proteinuria. In humans, GFR can be determined exactly by measuring the clearance of an ideal filtration marker, such as inulin. The classic method of measuring inulin clearance in humans includes constant intravenous infusion of the compound and timed collections of urine. In order to avoid the need for timed urine collections, a number of alternative procedures have been devised. All these methods only use determinations of inulin in plasma or serum. From these, the total body inulin clearance is obtained using pharmacokinetic calculations. In order to measure total body clearance, usually called plasma clearance, inulin is either given as a constant intravenous infusion or as a bolus infusion. Both procedures overestimate GFR because of incomplete distribution of inulin during the study periods. The error may be minimized by using model-independent pharmacokinetic calculations. Unlike inulin, creatinine is not a perfect filtration marker. This is because the substance is not only eliminated by glomerular filtration but also by tubular secretion. The extent of tubular creatinine secretion is not constant in various individuals. Serum creatinine concentration is a commonly used measure of renal function in clinical practice. This parameter is determined both by the renal elimination and by the production of the compound. Differences in creatinine production among subjects and over time in a single individual may occur because of changes in muscle mass. Radioisotopic filtration markers can easily and accurately be measured in plasma and serum. Using this method, the plasma concentration-time curve of these compounds can easily be studied after intravenous bolus injection. From the plasma concentration-time curves obtained, the total body clearance (plasma clearance) of the substances can be calculated using pharmacokinetic models. Most frequently, 125l-iothalamate, 99mTc-diethylenethiaminepenta-acetic acid and 51Cr-ethylenediaminetetra-acetic acid are used for the estimation of GFR in humans. The total body clearance of all these filtration markers overestimates GFR. The error induced by this phenomenon is particularly relevant at low levels of GFR. In recent years, iohexol has been used as a filtration marker. The substance can be measured in plasma, serum and urine using high-performance liquid chromatography. So far, good agreement has been shown for GFR determined by the classic inulin clearance and by the iohexol plasma clearance. Screening for proteinuria is commonly performed using reagent test strips. Quantitative measurements of marker proteins can be used to estimate the extent and the site of damage in the nephron. These measurements may be used to estimate the progression of renal disease and the response to therapeutic interventions. Of particular interest is the degree of albuminuria which indicates nephropathy in diabetic patients and end-organ damage in patients with hypertension.
- Published
- 1999
- Full Text
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290. Eye movements affect the perceived speed of visual motion.
- Author
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Turano KA and Heidenreich SM
- Subjects
- Humans, Psychological Tests, Psychophysics, Retina, Motion Perception physiology, Pursuit, Smooth physiology
- Abstract
Eye movements add a constant displacement to the visual scene, altering the retinal-image velocity. Therefore, in order to recover the real world motion, eye-movement effects must be compensated. If full compensation occurs, the perceived speed of a moving object should be the same regardless of whether the eye is stationary or moving. Using a pursue-fixate procedure in a perceptual matching paradigm, we found that eye movements systematically bias the perceived speed of the distal stimulus, indicating a lack of compensation. Speed judgments depended on the interaction between the distal stimulus size and the eye velocity relative to the distal stimulus motion. When the eyes and distal stimulus moved in the same direction, speed judgments of the distal stimulus approximately matched its retinal-image motion. When the eyes and distal stimulus moved in the opposite direction, speed judgments depended on the stimulus size. For small sizes, perceived speed was typically overestimated. For large sizes, perceived speed was underestimated. Results are explained in terms of retinal-extraretinal interactions and correlate with recent neurophysiological findings.
- Published
- 1999
- Full Text
- View/download PDF
291. ACE inhibitor versus beta-blocker for the treatment of hypertension in renal allograft recipients.
- Author
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Hausberg M, Barenbrock M, Hohage H, Müller S, Heidenreich S, and Rahn KH
- Subjects
- Adolescent, Adult, Blood Pressure drug effects, Creatinine blood, Cyclosporine therapeutic use, Double-Blind Method, Female, Heart Rate drug effects, Humans, Hypertension etiology, Hypertension metabolism, Immunosuppressive Agents therapeutic use, Male, Middle Aged, Proteinuria urine, Quinapril, Adrenergic beta-Antagonists therapeutic use, Angiotensin-Converting Enzyme Inhibitors therapeutic use, Atenolol therapeutic use, Hypertension drug therapy, Isoquinolines therapeutic use, Kidney Transplantation adverse effects, Tetrahydroisoquinolines
- Abstract
Angiotensin-converting enzyme (ACE) inhibitors have been shown to slow the progression of chronic renal failure. However, the value of ACE inhibitors for the treatment of hypertension in renal allograft recipients has not been established. ACE inhibitors dilate the efferent glomerular arteriole, an effect that may aggravate the decrease in glomerular filtration rate resulting from cyclosporine-induced vasoconstriction at the afferent glomerular arteriole. Therefore, the goal of this double-blind, randomized study was to compare the antihypertensive and renal effects of the ACE inhibitor quinapril with those of the beta-blocker atenolol in renal allograft recipients in whom hypertension developed 6 to 12 weeks after transplantation. All patients received cyclosporine as an immunosuppressant and had stable graft function (serum creatinine concentration, <220 micromol/L) at entry into the study. Twenty-nine patients who received quinapril (daily dose titrated between 2.5 and 20 mg) and 30 patients who received atenolol (daily dose titrated between 12.5 and 100 mg) completed the 24-month study. The two groups did not differ in age, sex ratio, height, and weight before entry into the study. Quinapril decreased diastolic blood pressure from 96+/-1 to 84+/-1 mm Hg (average throughout treatment period), and atenolol decreased diastolic blood pressure from 96+/-1 to 83+/-1 mm Hg. The serum creatinine concentration did not change significantly in either group after 24 months (129+/-8 micromol/L at entry and 148+/-19 micromol/L after 24 months in the quinapril group and 131+/-6 micromol/L at entry and 152+/-15 micromol/L after 24 months in the atenolol group; P=NS for both groups). After 24 months, the change in urinary albumin excretion from baseline was -10+/-15 mg/d in the quinapril group and 52+/-32 mg/d in the atenolol group (P=0.03). These results show that quinapril and atenolol are effective antihypertensive drugs when used after renal transplantation. Moreover, compared with atenolol, quinapril has no adverse effects on graft function. The relative reduction in albuminuria observed with quinapril as compared with atenolol could indicate a beneficial effect of quinapril on long-term graft function.
- Published
- 1999
- Full Text
- View/download PDF
292. Prognostic value of lymphocyte apoptosis in acute rejection of renal allografts.
- Author
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August C, Schmid KW, Dietl KH, and Heidenreich S
- Subjects
- Acute Disease, Female, Humans, In Situ Nick-End Labeling, Male, Prognosis, Proto-Oncogene Proteins c-bcl-2 analysis, Apoptosis, Graft Rejection, Kidney Transplantation immunology, Lymphocytes physiology
- Abstract
Background: Apoptosis is a cellular phenomenon generally found within rejecting transplants. It may play a role in physiological or therapy-associated deletion of infiltrating lymphocytes or in graft cell destruction. Our study focuses on apoptosis of infiltrating lymphocytes during acute kidney rejection after the initial steroid pulse therapy and on possible prognostic implications., Methods: Renal biopsy specimens of 23 transplant recipients with acute tubulo-interstitial rejection were examined for appearance of apoptosis and compared with 11 transplant biopsies with unspecific organ injury accompanied by lymphocyte infiltration. In all patients, biopsies were performed after steroid pulse therapy, and, after confirmation of rejection, antilymphocytic antibody treatment was carried out. Apoptosis was determined via terminal deoxynucleotidyltransferase-mediated dUTP-digoxigenin nick end labeling analysis and confirmed by electron microscopy., Results: Apoptosis of lymphocytes or of tubular epithelium was detected in 11 cases of acute rejection (48%), respectively. Four biopsies showed lymphocytic as well as tubular apoptosis, whereas five sections showed no signs of programmed cell death. In biopsies revealing unspecific injury, tubular cell apoptosis was more frequently found (73%) compared with lymphocyte apoptosis (27%, P<0.05). Most interestingly, patients with a beneficial recovery from acute rejection had a higher proportion of lymphocyte apoptosis compared with patients with poor rejection outcome. The Bcl-2 oncoprotein was widely found within infiltrating lymphocytes without counter-regulating apoptosis., Conclusions: Lymphocyte apoptosis is found as frequently as tubular cell apoptosis in rejecting renal grafts after steroid pulse therapy and might have prognostic value for rejection outcome.
- Published
- 1999
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293. High rate of acute rejections in renal allograft recipients with thrombophilic risk factors.
- Author
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Heidenreich S, Dercken C, August C, Koch HG, and Nowak-Göttl U
- Subjects
- Acute Disease, Adult, Biopsy, Needle, Female, Graft Rejection diagnosis, Graft Rejection epidemiology, Graft Survival, Humans, Male, Middle Aged, Prevalence, Prognosis, Reference Values, Risk Factors, Thrombophilia diagnosis, Transplantation, Homologous, Graft Rejection etiology, Kidney Transplantation, Thrombophilia complications
- Abstract
Inherited and acquired thrombophilic disorders predispose patients for thromboembolic and probably other occlusive vascular events that occur when additional risk factors play in concert. Because acute rejections in renal transplant recipients may reflect vascular events, and an impairment of the fibrinolytic system in immunosuppressed patients has been previously described, the implications of genetic or acquired risk factors of thrombophilia for the occurrence of early acute rejections after kidney transplantation were evaluated. The following risk factors of thrombophilia were determined in 97 patients after cadaveric kidney transplantation: factor V Leiden mutation, protein S, protein C, and antithrombin deficiency. In a retrospective analysis, the prevalence of acute rejections, the histologic classification when rejection episodes had been confirmed by biopsy, and other vascular complications were evaluated. In 21 of the 97 patients, an inherited or acquired risk factor of thrombophilia was detected. Prevalence of acute rejections was 71% in the first 6 mo after transplantation in patients with a thrombophilic disorder and significantly higher compared with patients without thrombophilia (41%; P = 0.017). The distribution of classic risk factors associated with acute rejections, such as number of human leukocyte antigen mismatches or percentage of panel-reactive antibodies, was similar in patients with and without thrombophilia. In the eight patients with thrombophilia and histologically proven acute rejection, four patients had an acute vascular rejection, and in two patients a vascular involvement was suspected. Furthermore, prevalence of cerebral or coronary vascular disease, or venous thromboembolic complications, was significantly higher in patients with a thrombophilic clotting defect (67%) compared with patients with normal hemostasis parameters (28%; P < 0.002). It is concluded that renal allograft recipients with thrombophilia are at risk of developing an acute rejection or other vascular event. Although the determination of thrombotic risk factors was performed at least 3 mo after an acute rejection episode, it can be presumed that acute rejection episodes are associated with subsequent coagulatory abnormalities with further consequences for transplant survival. Thus, pretransplant evaluation of genetic and acquired risk factors of thrombophilia is recommended.
- Published
- 1998
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294. Transgenic hypertensive rats show a reduced angiotensin II induced [Ca2+]i response in glomerular mesangial cells.
- Author
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Tepel M, Heidenreich S, and Zidek W
- Subjects
- Animals, Animals, Genetically Modified, Cytosol drug effects, Cytosol metabolism, Dose-Response Relationship, Drug, Glomerular Mesangium metabolism, Male, Platelet-Derived Growth Factor pharmacology, Rats, Rats, Inbred SHR, Rats, Inbred WKY, Rats, Sprague-Dawley, Angiotensin II pharmacology, Calcium metabolism, Glomerular Mesangium drug effects, Hypertension metabolism, Vasoconstrictor Agents pharmacology
- Abstract
The effects of angiotensin II (Ang II) induced changes of cytosolic free calcium concentration ([Ca2+]i) and growth response were investigated in transgenic TGR(mREN2)27 rats, a strain showing fulminant hypertension after the mouse Ren-2d renin gene has been integrated into its genome, in age-matched normotensive Sprague-Dawley rats (SD), in spontaneously hypertensive rats of the Münster strain (SHR), and in normotensive Wistar-Kyoto rats (WKY). In each strain the Ang II induced changes of [Ca2+]i were measured in cultured glomerular mesangial cells (MC) using the calcium-sensitive fluorescent dye, fura2. Resting [Ca2+]i was not significantly different between the strains tested. The Ang II induced [Ca2+]i rise was significantly less in MC from TGR(mREN2)27 compared to SD (peak level at 200 seconds: 161 +/- 15 nmol/L vs 217 +/- 43 nmol/L; mean +/- SEM; p<0.05). In the absence of external calcium, the Ang II induced [Ca2+]i increase was similar in MC from TGR(mREN2)27 and SD, indicating that the Ang II induced trans-plasma membrane calcium influx but not the calcium release is impaired in TGR(mREN2)27. The arginine vasopressin or endothelin induced [Ca2+]i increase were not significantly different in MC from TGR(mREN2)27 and SD. The Ang II or PDGF induced 3H-thymidine incorporation was not significantly different in MC from TGR(mREN2)27 and SD, indicating that the early growth response to Ang II is not impaired in TGR(mREN2)27. The Ang II induced peak [Ca2+]i increase was significantly enhanced in MC from SHR compared to WKY (215 +/- 30 nmol/L, n=17; vs 161 +/- 35 nmol/L, n=17; p<0.05). It is concluded that TGR(mREN2)27 show a selective defect in the cellular calcium response to Ang II.
- Published
- 1998
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295. Prothrombotic risk factors and acute kidney transplant rejection.
- Author
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Heidenreich S, August C, and Nowak-Göttl U
- Subjects
- Acute Disease, Graft Rejection pathology, Humans, Risk Factors, Thrombophilia complications, Thrombophilia pathology, Thrombosis pathology, Graft Rejection complications, Kidney Failure, Chronic therapy, Thrombosis complications
- Published
- 1998
- Full Text
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296. Regulation of human monocyte apoptosis by the CD14 molecule.
- Author
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Heidenreich S, Schmidt M, August C, Cullen P, Rademaekers A, and Pauels HG
- Subjects
- Annexin A5 metabolism, Apoptosis drug effects, Cells, Cultured, DNA chemistry, DNA Fragmentation drug effects, DNA Fragmentation immunology, Down-Regulation immunology, Electrophoresis, Agar Gel, HLA-A Antigens biosynthesis, HLA-B Antigens biosynthesis, HLA-C Antigens biosynthesis, Humans, Immunophenotyping, Interleukin-4 pharmacology, Lipopolysaccharide Receptors biosynthesis, Lipopolysaccharide Receptors genetics, Lipopolysaccharides pharmacology, Lymphocyte Subsets classification, Monocytes metabolism, Monocytes ultrastructure, Phosphatidylinositol Diacylglycerol-Lyase, Phosphoinositide Phospholipase C, Propidium, RNA, Messenger drug effects, RNA, Messenger metabolism, Time Factors, Type C Phospholipases pharmacology, Apoptosis immunology, Lipopolysaccharide Receptors physiology, Monocytes immunology
- Abstract
Bacterial products such as LPS have been shown to activate monocytes and to increase CD14 expression, while anti-inflammatory cytokines, i.e., IL-4, down-regulate CD14. Furthermore, activation of monocytes increases survival, whereas deactivation evokes apoptosis (programmed cell death, PCD). This correlation among activation, CD14 expression, and the lifespan of the cells prompted us to investigate the role of CD14 in monocyte apoptosis. The effects of LPS and IL-4 on the expression of CD14, indicated by binding of Leu M3 Ab, and PCD of monocytes were studied simultaneously and in a kinetic fashion by multiparameter flow cytometry. Monocyte PCD was determined by binding of FITC-conjugated annexin V, which indicates apoptotic cell death in early stages, and was confirmed using well-established detection methods, i.e., DNA electrophoresis, electron microscopy, or colorimetric DNA staining. The present study shows that the LPS-induced increase in CD14 expression rescued monocytes from apoptosis, whereas IL-4 treatment first down-regulated CD14 expression and consecutively evoked apoptosis. CD14-/annexin V- monocytes were not apoptotic as confirmed by DNA electrophoresis, whereas CD14-/ annexin V+ monocytes showed clear apoptotic features. Kinetic studies ruled out that monocytes first bound annexin V and later lost the CD14 Ag. Other molecules, such as HLA-A, -B, and -C Ags, were not down-regulated during apoptosis. Enzymatic removal of membrane-bound CD14 by phosphatidylinositol-specific phospholipase C evoked PCD similarly to IL-4. These results suggest that regulation of CD14 receptor expression is an early effector mechanism mediating life or death of monocytes. Down-regulation or removal of the receptor triggers apoptosis, whereas up-regulation promotes survival.
- Published
- 1997
297. Elemental mercurial poisoning.
- Author
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Hohage H, Otte B, Westermann G, Witta J, Welling U, Zidek W, and Heidenreich S
- Subjects
- Adult, Antidotes therapeutic use, Chelating Agents therapeutic use, Humans, Male, Suicide, Attempted, Unithiol therapeutic use, Mercury Poisoning diagnosis, Mercury Poisoning drug therapy
- Abstract
A 39-year-old man injected 40 mL of elemental mercury in an attempted suicide 3 years before coming to our facility. No specific treatment regimen had been done since then. Chest x-ray films showed mercury deposits in the lungs, as well as around the injection site. The mercury concentration in his blood was at 96.3 micrograms (0.480 nmol/L), thus significantly elevated (given a reference range of up to 2 micrograms Hg/L), as was the renal mercury elimination. Despite mercurial deposits within the pulmonary circulation, the pulmonary function showed normal values, with no reduction of the diffusion capacity. There were signs of polyneuropathy. The patient was given sodium dimercaptopropanesulfate (Dimaval) for mercury complexation. This case report outlines the diagnosis and therapy for mercurial poisoning through metallic mercury.
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- 1997
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298. Spatial sampling of motion: seeing an object moving behind a picket fence.
- Author
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Dannemiller JL, Heidenreich SM, and Babler T
- Subjects
- Adult, Humans, Psychophysics, Time Perception, Vision, Binocular, Vision, Monocular, Attention, Motion Perception, Orientation, Pattern Recognition, Visual, Perceptual Masking
- Abstract
Spatially sampled motion (H.P. Snippe & J.J. Koenderink, 1994) leads to time-lagged correlations of luminance change at discrete spatial positions. Observers matched the perceived width of a bar whose motion path was sampled spatially to the width of a static bar; the width of the moving object was not directly observable. Observers did reasonably well on this task when the stimulus onset asynchrony (SOA) between adjacent samples was approximately 90 ms, but performance broke down completely when the SOA was doubled. Performance improved considerably as more samples became available, provided that these samples all fell along the same smooth motion path and were seen by the same eye. This spatiotemporal information in spatially sampled motion can specify the width of a moving object, but it is likely to be useful to observers only if the sampling preserves the impression of motion.
- Published
- 1997
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299. Induction of mesangial interleukin-6 synthesis by apoptotic U937 cells and monocytes.
- Author
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Heidenreich S, Sato T, Schmidt M, August C, Timmerman JJ, van Es LA, and Daha MR
- Subjects
- Cell Adhesion drug effects, Cell Adhesion physiology, Cell Culture Techniques methods, Cell Division drug effects, Humans, Leukemia, Promyelocytic, Acute, Microscopy, Electron, Monocytes immunology, Phagocytosis physiology, Phosphoserine pharmacology, Tumor Cells, Cultured cytology, Tumor Cells, Cultured metabolism, Tumor Cells, Cultured ultrastructure, Zymosan pharmacology, Apoptosis physiology, Glomerular Mesangium cytology, Glomerular Mesangium metabolism, Interleukin-6 biosynthesis, Monocytes metabolism
- Abstract
Infiltration of the glomerular mesangium by monocytes and macrophages is a central pathologic feature in various forms of glomerulonephritis. Dependent on the presence and activity of local survival factors, monocytes may undergo apoptosis. Therefore, we looked for the interaction between cultured human mesangial cells (HMC) and intact, necrotic or apoptotic monocytic cells with different stages of programmed cell death (U937 cells and blood-derived human monocytes) and the possible evoked secretory responses of HMC. Interleukin-6 (IL-6) synthesis of HMC after a two hour co-culture with late apoptotic U937 cells was significantly increased (505 +/- 55 pg/ml) as compared to intact U937 cells (349 +/- 27 pg/ml; HMC alone, 319 +/- 62 pg/ml), and was further elevated after 20 hours (815 +/- 108 pg/ml). U937 cells alone, after incubation in HMC-conditioned medium or after coincubation with HMC, did not produce any detectable IL-6. A high mesangial IL-6 synthesis in response to apoptotic U937 cells was dependent on the cellular contact between HMC and U937 and could not be mimicked by apoptotic U937 culture supernatants. Radiolabeling studies indicated that HMC bound (16.6 +/- 2.4%) and ingested (12.5 +/- 1.9%) apoptotic U937 cells to a much higher amount as compared to intact U937 (5.3 +/- 2.0% binding; 5.0 +/- 1.1% phagocytosis). Binding and ingestion of monocytic cells undergoing apoptosis was confirmed by morphologic studies using electron microscopy. Incubation of HMC with a blocker of the CD36/ vitronectin receptor (VnR) dependent recognition mechanism of phagocytes for apoptotic leukocytes (RGDS peptide) did not alter binding, phagocytosis or IL-6 synthesis of HMC in response to apoptotic U937. Phospho-L-serine as an antagonist of the phosphatidylserine (PS) mediated recognition pathway for apoptotic cell disposal was able to reduce binding and IL-6 production by HMC but not phagocytosis. Thus, binding of apoptotic monocytic cells by HMC rather than ingestion may be the prerequisite for a stimulated secretory response. To elucidate whether binding and phagocytosis of particles in general might stimulate HMC to produce IL-6, we looked for mesangial IL-6 production after binding and ingestion of opsonized zymosan particles. In this case, IL-6 synthesis was markedly down-regulated. Furthermore, HMC proliferated after zymosan treatment, whereas after apoptotic cell uptake the mesangial cell number remained constant. In conclusion, apoptotic monocytic cells provoked an enhanced mesangial IL-6 synthesis by a PS-dependent recognition mechanism. This secretory response may have secondary implications for humoral or cellular processes within the mesangium.
- Published
- 1997
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300. [Magnetic resonance tomography without and with gadolinium-DTPA for evaluating kidney transplants].
- Author
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Vestring T, Dietl KH, Heidenreich S, Langenhorst U, Buchholz B, and Peters PE
- Subjects
- Adult, Aged, Female, Gadolinium DTPA, Humans, Infarction diagnosis, Infarction etiology, Kidney blood supply, Kidney pathology, Kidney Function Tests, Male, Middle Aged, Postoperative Complications etiology, Prospective Studies, Transplantation, Homologous, Contrast Media, Kidney Transplantation pathology, Magnetic Resonance Imaging methods, Organometallic Compounds, Pentetic Acid analogs & derivatives, Postoperative Complications diagnosis
- Abstract
Purpose: To determine the value of MR imaging in differentiating the various causes of human renal allograft dysfunction., Methods: A total of 123 human renal allografts (normal n = 20, acute rejection n = 57, acute tubular necrosis n = 14, interstitial fibrosis n = 11, chromic allograft glomerulopathy n = 11, cyclosporine nephrotoxicity n = 3, cortical necrosis n = 7) were investigated by means of MR imaging. Axial T1-weighted spin-echo images and coronal T1-weighted gradient-echo images were obtained before and after Gd-DTPA injection. Diagnostic parameters included corticomedullary contrast and allograft size and shape on the pre-contrast sequences., Results: None of the diagnostic parameters used could differentiate among the various diagnostic groups. Diagnostic of cortical necrosis could be made only on post-contrast scans. Contrast-enhanced scans were superior to pre-contrast images in detection of focal allograft lesions. Otherwise, contrast-enhanced scans did not provide any more information than pre-contrast studies. Spin-echo and gradient-echo sequences displayed the same diagnostic value., Conclusions: MR imaging has a limited value in differentiating the various causes of renal allograft dysfunction.
- Published
- 1997
- Full Text
- View/download PDF
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