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AboJabel H, Welsch J, Schicktanz S. Cross-cultural perspectives on intelligent assistive technology in dementia care: comparing Israeli and German experts' attitudes. BMC Med Ethics 2024; 25:15. [PMID: 38326778 PMCID: PMC10848426 DOI: 10.1186/s12910-024-01010-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 02/01/2024] [Indexed: 02/09/2024] Open
Abstract
BACKGROUND Despite the great benefits of intelligent assistive technology (IAT) for dementia care - for example, the enhanced safety and increased independence of people with dementia and their caregivers - its practical adoption is still limited. The social and ethical issues pertaining to IAT in dementia care, shaped by factors such as culture, may explain these limitations. However, most studies have focused on understanding these issues within one cultural setting only. Therefore, the aim of this study was to explore and compare the attitudes of Israeli and German dementia experts toward IAT in dementia care, to contribute to a more cultural-comparative perspective. METHODS Semi-structured interviews were conducted with 35 experts (15 Israelis and 20 Germans) in key roles in health and community services for people with dementia as well as in the fields of dementia and IAT (e.g., computer science, electrical/biomedical engineering, ethics, nursing, and gerontology). Thematic content analysis was used to analyze the data. FINDINGS Israeli and German experts identified the same social accelerators in the development and implementation of IAT in dementia care (i.e., changes in family structure and social digitization) and benefits of adopting IAT (e.g., enhancing the safety of people with dementia and increasing their independence). However, there were differences in inhibitor/risk assessments between the two groups. Namely, economic considerations and the cognitive capacity of people with dementia were identified by both groups as inhibitors, while Israeli experts additionally reported stigma and ageism. Whereas both groups agreed that IAT might reduce human connection, and that the technology is not yet reliable enough, German experts highlighted concerns regarding privacy; in contrast, Israeli experts prioritized safety over privacy. CONCLUSIONS Our research findings allow for the identification of relevant similarities but also important differences between German and Israeli experts' perspectives. As such, an important basis has been provided for a more in-depth discussion regarding where, why, and how culturally-sensitive technology development is needed.
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Affiliation(s)
- Hanan AboJabel
- Department of Medical Ethics and History of Medicine, University Medical Center Göttingen, Göttingen, Germany.
- The Paul Baerwald School of Social Work and Social Welfare, The Hebrew University of Jerusalem, Jerusalem, Israel.
| | - Johannes Welsch
- Department of Medical Ethics and History of Medicine, University Medical Center Göttingen, Göttingen, Germany
| | - Silke Schicktanz
- Department of Medical Ethics and History of Medicine, University Medical Center Göttingen, Göttingen, Germany
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Schicktanz S, Welsch J, Schweda M, Hein A, Rieger JW, Kirste T. AI-assisted ethics? considerations of AI simulation for the ethical assessment and design of assistive technologies. Front Genet 2023; 14:1039839. [PMID: 37434952 PMCID: PMC10331421 DOI: 10.3389/fgene.2023.1039839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Accepted: 05/23/2023] [Indexed: 07/13/2023] Open
Abstract
Current ethical debates on the use of artificial intelligence (AI) in healthcare treat AI as a product of technology in three ways. First, by assessing risks and potential benefits of currently developed AI-enabled products with ethical checklists; second, by proposing ex ante lists of ethical values seen as relevant for the design and development of assistive technology, and third, by promoting AI technology to use moral reasoning as part of the automation process. The dominance of these three perspectives in the discourse is demonstrated by a brief summary of the literature. Subsequently, we propose a fourth approach to AI, namely, as a methodological tool to assist ethical reflection. We provide a concept of an AI-simulation informed by three separate elements: 1) stochastic human behavior models based on behavioral data for simulating realistic settings, 2) qualitative empirical data on value statements regarding internal policy, and 3) visualization components that aid in understanding the impact of changes in these variables. The potential of this approach is to inform an interdisciplinary field about anticipated ethical challenges or ethical trade-offs in concrete settings and, hence, to spark a re-evaluation of design and implementation plans. This may be particularly useful for applications that deal with extremely complex values and behavior or with limitations on the communication resources of affected persons (e.g., persons with dementia care or for care of persons with cognitive impairment). Simulation does not replace ethical reflection but does allow for detailed, context-sensitive analysis during the design process and prior to implementation. Finally, we discuss the inherently quantitative methods of analysis afforded by stochastic simulations as well as the potential for ethical discussions and how simulations with AI can improve traditional forms of thought experiments and future-oriented technology assessment.
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Affiliation(s)
- Silke Schicktanz
- University Medical Center Göttingen, Department for Medical Ethics and History of Medicine, Göttingen, Germany
- Hanse-Wissenschaftskolleg, Institute of Advance Studies, Delmenhorst, Germany
| | - Johannes Welsch
- University Medical Center Göttingen, Department for Medical Ethics and History of Medicine, Göttingen, Germany
| | - Mark Schweda
- University of Oldenburg, Department of Health Services Research, Division for Ethics in Medicine, Oldenburg, Germany
| | - Andreas Hein
- University of Oldenburg, Department of Health Services Research, Division Assistance Systems and Medical Device Technology, Oldenburg, Germany
| | - Jochem W. Rieger
- University of Oldenburg, Applied Neurocognitive Psychology Lab, Oldenburg, Germany
| | - Thomas Kirste
- University of Rostock, Institute for Visual and Analytic Computing, Rostock, Germany
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Furrer K, Welsch J, Bettex D, Horisberger T, Inci I, Schuepbach R, Kirschner M, Ulrich S, Matter A, Opitz I. Carbon Dioxide and Alveolar Dead Space as a Prognostic Marker for Patients Undergoing Pulmorary Endarterectomy. J Heart Lung Transplant 2022. [DOI: 10.1016/j.healun.2022.01.1544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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Kup P, Welsch J, Bühler H, Hermani H, Adamietz I, Fakhrian K. EP-1263: Survival and symptom relief after palliative radiotherapy for esophageal cancer. Radiother Oncol 2016. [DOI: 10.1016/s0167-8140(16)32513-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Hymer WC, Welsch J, Buchmann E, Risius M, Whelan HT. Modulation of rat pituitary growth hormone by 670 nm light. Growth Horm IGF Res 2009; 19:274-279. [PMID: 19091612 DOI: 10.1016/j.ghir.2008.11.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2008] [Revised: 11/03/2008] [Accepted: 11/04/2008] [Indexed: 11/26/2022]
Abstract
In rat pituitary somatotrophs, cytochrome oxidase is co-packaged with growth hormone (GH) in some storage granules. Because this enzyme is thought to be the molecular photoacceptor of red-near infrared light, and because exposure of diverse tissue systems to 670 nm visible light affects their biological responses (e.g., wound healing), we tested the idea that exposure of rat pituitary cells, rat hemi-pituitary glands and rat pituitary homogenates to 670 nm light in vitro might alter GH storage and/or release. In this report we offer evidence to show that light treatment (670 nm, 80s, intensity 50 mW/cm(2), energy density 4 J/cm(2)) up-regulates GH release, in part by breakdown of intracellular, oligomeric GH as determined by gel filtration chromatography.
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Affiliation(s)
- W C Hymer
- Centralized Biological Laboratory, Penn State University, University Park, PA 16802-4803, USA.
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Happe S, Tings T, Koch W, Welsch J, Helmschmied K, Baier PC, Meller J, Wuttke W, Paulus W, Tatsch K, Trenkwalder C. Growth hormone response in low-dose apomorphine test correlates with nigrostriatal dopamine transporter binding in patients with Parkinson’s disease. J Neural Transm (Vienna) 2006; 114:589-94. [PMID: 17187291 DOI: 10.1007/s00702-006-0611-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2006] [Accepted: 11/08/2006] [Indexed: 10/23/2022]
Abstract
Challenge with low-dose apomorphine causes a rise in growth hormone (GH) in patients with Parkinson's disease (PD). We studied 18 patients with early PD, who showed an increase of GH in the low-dose apomorphine test, by means of [(123)I] FP-CIT-SPECT. The mean specific dopamine transporter binding of the 18 patients was 1.50 +/- 0.56 in the striatum, 1.20 +/- 0.59 in the putamen, and 1.76 +/- 0.59 in the caudate nucleus. The increase of GH (1.05 +/- 1.01 ng/ml at baseline to 9.46 +/- 6.36 ng/ml 45 min after apomorphine injection; p < 0.001) was significant. There was a significant negative correlation of the increase of GH with the mean specific dopamine transporter binding in all three regions (r between -0.490 and -0.587; p between 0.04 and 0.01). Challenge with low-dose apomorphine may therefore be used as an indirect tool to measure the extent of nigrostriatal neurodegeneration in early PD.
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Affiliation(s)
- S Happe
- Department of Clinical Neurophysiology, University of Göttingen, Göttingen, Germany.
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Siegmund B, Welsch J, Loher F, Meinhardt G, Emmerich B, Endres S, Eigler A. Phosphodiesterase type 4 inhibitor suppresses expression of anti-apoptotic members of the Bcl-2 family in B-CLL cells and induces caspase-dependent apoptosis. Leukemia 2001; 15:1564-71. [PMID: 11587214 DOI: 10.1038/sj.leu.2402232] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
B cell chronic lymphocytic leukemia (B-CLL) is an incurable clonal disease which shows initial responsiveness to a number of chemotherapeutic drugs. However, in most patients the disease becomes resistant to treatment. Rolipram, a specific inhibitor of phosphodiesterase (PDE) type 4, the PDE predominantly expressed in B-CLL cells, has been shown to induce cAMP-dependent apoptosis in these cells. In the present study, we demonstrate that the extent of rolipram-induced apoptosis is similar to fludarabine-induced apoptosis in vitro. The combination of rolipram and fludarabine results in an enhancement in the number of apoptotic cells compared to apoptosis induced by either agent alone. Second, rolipram suppresses the expression of anti-apoptotic members of the Bcl-2 family and induces the pro-apoptotic protein Bax, thereby shifting the balance between pro- and anti-apoptotic members of the Bcl-2 family towards a pro-apoptotic direction. Finally rolipram-induced apoptosis is caspase-dependent. PDE 4 inhibitors are currently under investigation for chronic obstructive pulmonary disease and asthma in phase III clinical trials showing promising results with tolerable side-effects. In conclusion, by inducing apoptosis, by enhancing apoptosis induced by fludarabine, by suppressing Bcl-2, Bcl-X and by inducing Bax expression, PDE 4 inhibitors may add a new therapeutic option for patients with B-CLL.
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MESH Headings
- 3',5'-Cyclic-AMP Phosphodiesterases/antagonists & inhibitors
- Aged
- Antineoplastic Agents/pharmacology
- Apoptosis/drug effects
- Caspases/metabolism
- Caspases/pharmacology
- Cyclic Nucleotide Phosphodiesterases, Type 4
- Down-Regulation
- Drug Interactions
- Female
- Humans
- Leukemia, Lymphocytic, Chronic, B-Cell/enzymology
- Leukemia, Lymphocytic, Chronic, B-Cell/metabolism
- Leukemia, Lymphocytic, Chronic, B-Cell/pathology
- Male
- Middle Aged
- Mitoxantrone/pharmacology
- Phosphodiesterase Inhibitors/pharmacology
- Proto-Oncogene Proteins c-bcl-2/drug effects
- Proto-Oncogene Proteins c-bcl-2/metabolism
- Rolipram/pharmacology
- Tumor Cells, Cultured/drug effects
- Vidarabine/analogs & derivatives
- Vidarabine/pharmacology
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Affiliation(s)
- B Siegmund
- Division of Clinical Pharmacology, Medizinische Klinik Innenstadt, Klinikum of the Ludwig-Maximilians-University Munich, Germany
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Abstract
We have used free flow electrophoresis (FFE) technology to study the electrophoretic behavior of growth hormone (GH) molecules, GH secretory granules and GH cell subpopulations contained in pituitary glands of humans and rodents. GH activities in different electrophoresis fractions were measured by immunoassay or bioassay, viz., measurement of chondrocyte proliferation in the tibial growth plate of the hypophysectomized rat. Using FFE we discovered a peptide in human post mortem pituitary tissue and cryopoor human plasma that is active in the tibial line bioassay, is inactive in a GH immunoassay, and is neither GH nor a GH fragment. This peptide, called tibial peptide, has high anodal mobility and is readily separable from GH by FFE. Its molecular mass is approximately 5 kD. It is particularly rich in glycine. A partial amino acid sequence (residues 9-25) in the middle region of the peptide shows that 9 of the 16 residues are nonpolar. On the basis of results from other FFE experiments, using either GH-containing secretory granules or GH-producing cells, we believe that the peptide is stored within the secretion granule of a subpopulation of GH cells. On the basis of recent information elucidating the role of C peptide contained in the insulin storage granule of the pancreatic cell, we propose that the tibial peptide serves a similar role in the GH cell. Thus, not only may tibial peptide aid in proper alignment of disulfide bonds between GH monomers in the secretory granule, but, like the C peptide, it also appears to have biologic activity in its own right.
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Affiliation(s)
- W Hymer
- Department of Biochemistry and Molecular Biology, Penn State University, University Park, PA 16802, USA.
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Gulbins E, Welsch J, Lepple-Wienhuis A, Heinle H, Lang F. Inhibition of Fas-induced apoptotic cell death by osmotic cell shrinkage. Biochem Biophys Res Commun 1997; 236:517-21. [PMID: 9240472 DOI: 10.1006/bbrc.1997.6775] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Apoptosis is an active physiological mechanism permitting the elimination of cells by triggering an intracellular signalling cascade. Here, we tested whether osmotic alterations of cell volume interfere with apoptotic cell death in Jurkat T-lymphocytes. Apoptotic cell death of Jurkat cells was elicited by activation of the Fas receptor which results in sphingomyelinase stimulation, release of ceramide, activation of Ras, Rac-proteins and formation of O2. Osmotic cell shrinkage inhibited apoptotic cell death induced by the Fas receptor in Jurkat T-lymphocytes. Osmotic cell shrinkage did not interfere with Fas induced activation of the acidic sphingomyelinase or activation of Ras but impaired the formation of O2 suggesting an important function of cell volume in the synthesis of reactive oxygen intermediates upon Fas receptor ligation.
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Affiliation(s)
- E Gulbins
- Department of Physiology, University of Tuebingen, Germany
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Gulbins E, Brenner B, Schlottmann K, Welsch J, Heinle H, Koppenhoefer U, Linderkamp O, Coggeshall KM, Lang F. Fas-induced programmed cell death is mediated by a Ras-regulated O2- synthesis. Immunology 1996; 89:205-12. [PMID: 8943716 PMCID: PMC1456492 DOI: 10.1046/j.1365-2567.1996.d01-743.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Fas induces apoptosis in lymphocytes via a poorly defined intracellular signalling cascade. Previously, we have demonstrated the involvement and significance of a signalling cascade from the Fas receptor via sphingomyelinases and ceramide to Ras in Fas-induced apoptosis. Here we demonstrate rapid and transient synthesis of reactive oxygen intermediates (ROI) via activation of Ras after Fas. Genetic inhibition of Ras by transfection of transdominant inhibitory N17Ras blocked Fas-mediated ROI synthesis and programmed cell death. Likewise, the antioxidants N-acetyl-cysteine and N-t-butyl-phenylnitrone abolished Fas-induced cell death, pointing to an important role for Ras-triggered ROI synthesis in Fas-mediated programmed cell death.
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Affiliation(s)
- E Gulbins
- Institute of Physiology, University of Tuebingen, Germany
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Schaaf P, Blaes L, Welsch J, Jacoby H, Aubertin F, Gonser U. Experience with a toroidal proportional detector for backscattered Mössbauer ψ-rays and X-rays. ACTA ACUST UNITED AC 1990. [DOI: 10.1007/bf02398374] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Abstract
Experiments were performed on rats subjected to renal ischemia and various treatment procedures to determine the origin and functional consequences of vascular obstruction. To this end, its occurrence and severity was assessed qualitatively and quantitatively in the outer medulla, where it is particularly prominent. The incidence of medullary hyperemia was not influenced by inhibiting thrombocyte aggregation with 5 or 70 mg/kg of acetyl salicylic acid or preventing fibrin deposition with 100 IE/kg of heparin before ischemia, and these substances produced no improvement renal function. The incidence and degree of hyperemia, however, could be substantially reduced or completely eliminated by acutely raising blood pressure after ischemia or by decreasing the number of circulating erythrocytes before ischemia. These procedures were effective in raising filtration rate and tubular reabsorption from 20% to 60% of normal, in restoring renal blood flow and vascular resistance to completely normal, and in diminishing epithelial damage both three and 18 hours after ischemia. The following conclusions are drawn: first, vascular obstruction, which is not lessened by inhibiting thrombus formation but is easily reversed or prevented by raising perfusion pressure or decreasing hematocrit, is probably caused by erythrocyte aggregation during ischemia. Second, vascular obstruction, which appears to raise renal vascular resistance and lower blood flow and filtration rate, cannot be limited to the medulla but must also be present in the cortex. Finally, reversing or preventing vascular obstruction can fully restore renal perfusion, partially restore glomerular and tubular function, greatly reduce tubular necrosis and thus prevent renal failure.
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Abstract
Experiments were performed on rats to investigate the significance of the medullary hyperemia known to follow renal ischemia. To this end, its frequency was determined, its severity was quantified, and its relation to renal function was examined early (1 to 3 hr) and later (18 hr) after 45 min of warm ischemia. All kidneys were found to have a hyperemic outer medulla early after ischemia, which was shown to develop during the period of ischemia itself, but which was found to be highly variable in its severity. The degree of hyperemia was assessed both subjectively by grading and by histometric determinations of inner stripe capillary volume. One to hours after ischemia, the severity of medullary hyperemia was reflected in all indices of renal function, the least congested kidneys showing the best function. Eighteen hours after ischemia, the degree of medullary hyperemia was reflected in all indices of renal function, except urine flow rate; the non-congested kidneys showed functional recovery and the still-congested kidneys showed worsening function. Glomerular blood flow, known to be preferentially reduced in deep nephrons 1 to 3 hr after ischemia, had normalized 18 hr after ischemia in the non-congested kidneys but was still severely and unevenly depressed in the congested kidneys. It is concluded that congestion of the outer medulla is a key event in ischemic renal failure, its occurrence is coincidental with the reduction in deep nephron perfusion and urinary concentrating power in the early and maintenance phase and its disappearance heralds the restoration of deep nephron perfusion and urinary concentrating ability in the recovery phase.
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Abstract
Experiments were performed using a variety of methods to assess the functional status of different nephron populations following 45 min of renal ischemia in the rat. Micropuncture techniques revealed that SNGFR and reabsorption in the surface nephrons are only modestly reduced after ischemia, whereas kidney GFR and reabsorption are more severely affected. Determinations of bolus velocity with the Hanssen technique or of glomerular blood flow with the microsphere method confirmed that both were highest in the surface nephrons, lower in the middle nephrons and lowest of all in the juxtamedullary nephrons after ischemia. It is concluded that surface nephron function is well-maintained following ischemia and that it is the functional deficiency of the deeper nephrons that is predominantly responsible for the impairment in whole kidney function. Although the pathogenic mechanism is not yet clear, neither tubular obstruction nor tubular leakage in the deeper nephrons seems to be involved. The present findings suggest that micropuncture of the surface nephrons is a technique of questionable validity for studying this type of acute renal failure, they explain the inability of the kidney to concentrate the final urine, and they predict a more pronounced deficiency in medullary than in outer cortical blood flow.
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Abstract
Experiments were performed to determine whether furosemide, given in doses high enough to induce a strong diuresis and to inhibit the mechanism of tubuloglomerular feedback, offers any protection from acute renal failure induced by a nephrotoxin or ischaemia. Microperfusion of the loop of Henle revealed that a tubular furosemide concentration of 5 x 10(-5) mol x 1(-1) was necessary to fully inhibit the tubuloglomerular feedback response to a raised sodium chloride concentration at the macula densa. The infusion of furosemide systemically to achieve such concentrations in the tubule resulted in an improvement in renal function when given before or after the nephrotoxin but was without effect when given before or after ischaemia. Measurements of furosemide concentrations in the urine, however, confirmed that sufficient amounts were applied to inhibit the feedback mechanism. It is concluded from this and similar studies that furosemide is only beneficial in models of acute renal failure with an obstructive or nephrotoxic pathogenesis, in which it acts by flushing out the noxious material and not by inhibiting the mechanism of tubuloglomerular feedback.
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Mason J, Kain H, Shiigai T, Welsch J. The early phase of experimental acute renal failure. V. The influence of suppressing the renin-angiotensin system. Pflugers Arch 1979; 380:233-43. [PMID: 573464 DOI: 10.1007/bf00582902] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Experiments were conducted to determine whether suppression of the renin-angiotensin-system and inhibition of the tubuloglomerular feedback response offer protection from acute renal failure, as found in chronically-salt loaded animals. The juxtaglomerular renin activity and tubuloglomerular feedback response were inhibited acutely, by saline expansion, or chronically, by DOCA-treatment with saline drinking fluid or salt diet, by high salt diet alone, or by inducing two-kidney Goldblatt hypertension. The chronic pretreatment procedures depressed juxtaglomerular renin to 16, 7, 13 and 4% of control, respectively, inhibited the feedback response to 53, 37, 56, and 38% of control, respectively, but conferred no benefit in the first hours following a nephrotoxin or ischaemia. In contrast, the acute treatment procedure reduced juxtaglomerular renin activity to only 56% and lowered the feedback response to only 71%, but improved renal function after the nephrotoxin, although not after ischaemia. It is concluded that since severe restrictions of renin activity and tubuloglomerular feedback are not protective, neither is primarily involved in generating the functional restrictions early in acute renal failure. The restoration of renal function by saline expansion accompanied only a modest depression of these two systems and suggests that the beneficial effect may result more from volume expansion or diuresis than from suppression of renal renin or inhibition of tubuloglomerular feedback.
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Volkmer I, Nienhaus K, Wenzel E, Jäger H, Welsch J, Meiser J, Vief B. Antithrombin III and Platelet Volume in Correlation with Hemolysis after Valve Replacements Using Xenografts. Thromb Haemost 1979. [DOI: 10.1055/s-0039-1684442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Blood corpuscles as well as plasma proteins are traumatized, when blood comes in contact with surfaces of artificial heart valves. 30 patients who had received valve replacement (N = 18, Edwards Xenografts in aortic position; N = 12, Hancock Xenografts in mitral position) in addition to the parameters for hemolysis (haptoglobin, LDH, erythrocyte count, hemoglobin), platelet count, platelet volume distribution (Coulter Counter equipment) and coagulation parameters (PTT, PTZ, fibrinogen, plasmathrombin- and thrombincoagulase times, thrombelastography) were controlled. Antithrombin III was evaluated immunologically (Mancini) and photometrically (Chromozym TH). Laboratory and clinical investigations were performed postoperatively after 6 weeks and thereafter every 3 months (19.5 months). A significant higher rate of hemolysis was observed in patients with an aortic valve replacement. Antithrombin III was found to be significantly decreased, especially in patients with aortic valve replacements. A significant and comparable increase in small platelets (< 4.3 μ3) was observed in both patients’ groups.
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