scholarly journals Purinoceptors, Renal Microvascular Function and Hypertension

2020 ◽  
pp. 353-369
Author(s):  
Z GUAN ◽  
M MAKLED ◽  
E INSCHO
Keyword(s):  
Blood Flow ◽  
Kidney Function ◽  
Ischemia Reperfusion ◽  
Kidney Injury ◽  
Microvascular Dysfunction ◽  
Microvascular Function ◽  
Renal Autoregulation ◽  
Electrolyte Homeostasis ◽  
Renal Microvasculature ◽  
Autoregulatory Mechanism

Proper renal blood flow (RBF) and glomerular filtration rate (GFR) are critical for maintaining normal blood pressure, kidney function and water and electrolyte homeostasis. The renal microvasculature expresses a multitude of receptors mediating vasodilation and vasoconstriction, which can influence glomerular blood flow and capillary pressure. Despite this, RBF and GFR remain quite stable when arterial pressure fluctuates because of the autoregulatory mechanism. ATP and adenosine participate in autoregulatory control of RBF and GFR via activation of two different purinoceptor families (P1 and P2). Purinoceptors are widely expressed in renal microvasculature and tubules. Emerging data show altered purinoceptor signaling in hypertension-associated kidney injury, diabetic nephropathy, sepsis, ischemia-reperfusion induced acute kidney injury and polycystic kidney disease. In this brief review, we highlight recent studies and new insights on purinoceptors regulating renal microvascular function and renal hemodynamics. We also address the mechanisms underlying renal microvascular injury and impaired renal autoregulation, focusing on purinoceptor signaling and hypertension-induced renal microvascular dysfunction. Interested readers are directed to several excellent and comprehensive reviews that recently covered the topics of renal autoregulation, and nucleotides in kidney function under physiological and pathophysiological conditions (Inscho 2009, Navar et al. 2008, Carlstrom et al. 2015, Vallon et al. 2020).

scholarly journals Restoration of Afferent Arteriolar Autoregulatory Behavior in Ischemia-Reperfusion Injury in Rat Kidneys

2021 ◽  
Author(s):  
Wenguang Feng ◽  
Colton E. Remedies ◽  
Ijeoma E. Obi ◽  
Stephen R. Aldous ◽  
Samia I. Meera ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Polyethylene Glycol ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Kidney Injury ◽  
Microvascular Dysfunction ◽  
Renal Tissue ◽  
Artery Occlusion ◽  
Renal Autoregulation ◽  
Baseline Diameter

Renal autoregulation is critical in maintaining stable renal blood flow (RBF) and glomerular filtration rate (GFR). Renal ischemia-reperfusion (IR) induced kidney injury is characterized by reduced RBF and GFR. The mechanisms contributing to renal microvascular dysfunction in IR have not been fully determined. We hypothesized that increased reactive oxygen species (ROS) contributed to impaired renal autoregulatory capability in IR rats. Afferent arteriolar autoregulatory behavior was assessed using the blood-perfused juxtamedullary nephron preparation. IR was induced by 60-minutes of bilateral renal artery occlusion followed by 24 hours of reperfusion. Afferent arterioles from sham rats exhibited normal autoregulatory behavior. Stepwise increases in perfusion pressure caused pressure-dependent vasoconstriction to 65±3% of baseline diameter (13.2±0.4 μm) at 170 mmHg. In contrast, pressure-mediated vasoconstriction was markedly attenuated in IR rats. Baseline diameter averaged 11.7±0.5 µm and remained between 90-101% of baseline over 65-170 mmHg, indicating impaired autoregulatory function. Acute antioxidant administration (Tempol or apocynin) to IR kidneys for 20 minutes increased baseline diameter and improved autoregulatory capability, such that the pressure-diameter profiles were indistinguishable from those of sham kidneys. Furthermore, addition of polyethylene glycol superoxide dismutase (PEG-SOD) or polyethylene glycol catalase (PEG-catalase) to the perfusate blood also restored afferent arteriolar autoregulatory responsiveness in IR rats, indicating involvement of superoxide and/or hydrogen peroxide. IR elevated mRNA expression of NADPH oxidase subunits and MCP-1 in renal tissue homogenates and this was prevented by Tempol pre-treatment. These results suggest that ROS accumulation, likely involving superoxide and/or hydrogen peroxide, impairs renal autoregulation in IR rats in a reversible fashion.

Tempol Improves Renal Autoregulation and Kidney Function Following Ischemia‐Reperfusion Injury in Rats

2020 ◽  
Vol 34 (S1) ◽  
pp. 1-1
Author(s):  
Zhengrong Guan ◽  
Wenguang Feng ◽  
Colton E. Remedies ◽  
Bailey A. McEachen ◽  
Paul W. Sanders ◽  
...  
Keyword(s):  
Reperfusion Injury ◽  
Kidney Function ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Renal Autoregulation

scholarly journals Relevant Role of Von Willebrand Factor in Ischemia-Reperfusion Model of Acute Kidney Injury in Mice

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 2243-2243
Author(s):  
Shiro Ono ◽  
Hideto Matsui ◽  
Masashi Noda ◽  
Shogo Kasuda ◽  
Yasunori Matsunari ◽  
...  
Keyword(s):  
Acute Kidney Injury ◽  
Blood Flow ◽  
Renal Blood Flow ◽  
Inflammatory Responses ◽  
Ischemia Reperfusion ◽  
Kidney Injury ◽  
Relevant Role ◽  
Von Willebrand ◽  
Willebrand Factor

Abstract Acute kidney injury (AKI), an abrupt loss of renal function, is often seen in clinical settings and its mortality remains high even in the developed countries. An adhesive protein von Willebrand factor (VWF) plays a pivotal role in platelet thrombus formation and is recently understood as a key protein in a cross-talk between inflammation and thrombosis. Recent mouse model studies demonstrated that VWF-mediated thrombotic and inflammatory responses could play a role in the disease progression of myocardial infarction or brain stroke. Thus, we assumed that VWF may also be involved in the pathophysiology of AKI, the major cause of which could be an insufficient renal circulation and/or inflammatory cell infiltration in the kidney. To test this hypothesis, we studied the relevant role of VWF in AKI in mouse model of acute ischemia-reperfusion (I/R) kidney injury. All mice used were male, 8-12 weeks of age, healthy and whose right kidney was surgically removed by the standard mouse nephrectomy procedure 1 week prior to the kidney I/R experiment. The preliminary experiments confirmed that surgical removal of mouse right kidney did not affect their general conditions including renal functions. Mice were anesthetized with inhaled isoflurane and then placed in an abdominal position on a heating pad. Surgical incision was given on the left side of back and the left kidney was brought out and kept outside during the operation. Both renal artery and vein were clamped at the renal hilus by a clamping clip for 30 min ischemia. Then a clip was taken off to provoke the reperfusion of renal blood flow, which was monitored by Laser Doppler flowmetry (ALF21, Advance Co, Tokyo, Japan). The kidney was then put back in a body and skin incision was closed. The renal blood flow was measured again 30 h after reperfusion and mice were then sacrificed for blood collection. We compared 15 wild-type (WT) and 16 VWF-gene deleted (knock-out; KO) mice (from The Jackson Laboratory, Bar Harbor, ME). Excess blood loss was not observed in all mice (WT or KO) during whole surgical process. Although no difference was seen immediately after reperfusion, significantly (p < 0.05) higher renal blood flow at 30 h after reperfusion was confirmed in VWF-KO mice, as compared to WT (KO; 24.0±2.3 vs. WT; 15.1±1.46 ml/min/100g of kidney weight, and the reperfusion/base flow ratio: KO; 1.0±0.07 vs. WT; 0.6 ±0.07). Consistent with the renal blood flow data, the serum creatinine value at 30 h after reperfusion were significantly (p < 0.05) lower in VWF-KO mice than WT (KO; 2.77±0.11 vs. WT; 3.15±0.11 mg/dl). Our results suggest that VWF does play a role in the pathogenesis of AKI, in which VWF-dependent thrombotic or inflammatory responses may trigger thrombotic ischemia or endothelial damages of vascular bed in the kidney. Thus, proper functional regulation of VWF would be beneficial for better microcirculation and vessel functions in the kidney, suggesting a novel therapeutic potential against AKI. Disclosures No relevant conflicts of interest to declare.

scholarly journals Long-Term Administration of Angiotensin (1–7) to db/db Mice Reduces Oxidative Stress Damage in the Kidneys and Prevents Renal Dysfunction

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Anna Malgorzata Papinska ◽  
Kathleen Elizabeth Rodgers
Keyword(s):  
Oxidative Stress ◽  
Blood Flow ◽  
Kidney Function ◽  
Kidney Injury ◽  
Renal Arteries ◽  
Plasma Creatinine ◽  
Protective Mechanisms ◽  
Term Administration ◽  
Stress Damage

Aims. The goal of this study was to evaluate the effects of long-term (16 weeks) administration of angiotensin (1–7) [A(1–7)] on kidney function in db/db mice and to identify the protective mechanisms of this therapy. Methods. db/db mice and heterozygous controls were treated with A(1–7) or vehicle daily, subcutaneously for up to 16 weeks. Kidney injury was assessed by measuring blood flow in renal arteries, plasma creatinine levels, and proteinuria. Effects of treatment on oxidative stress were evaluated by histological staining and gene expression. Results. 16 weeks of daily administration of A(1–7) to a mouse model of severe type 2 diabetes (db/db) prevented the progression of kidney damage. Treatment with A(1–7) improved blood flow in the renal arteries, as well as decreased plasma creatinine levels and proteinuria in diabetic mice. Reduction of oxidative stress was identified as one of the mechanisms of the renoprotective action of A(1–7). Treatment prevented formation of nitrotyrosine residues, a marker of oxidative stress damage. A(1–7) also reduced the expression of two enzymes involved in formation of nitrotyrosine, namely, eNOS and NOX-4. A(1–7) regulated the phosphorylation pattern of eNOS to enhance production of NO in diabetic animals, possibly through the Akt pathway. However, these elevated levels of NO did not result in increased nitrosylation, possibly due to reduced NOX-4 levels. Conclusions. Long-term administration of A(1–7) improved kidney function and reduced oxidative stress damage in db/db mice.

scholarly journals Functional regulation of von Willebrand factor ameliorates acute ischemia-reperfusion kidney injury in mice

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Shiro Ono ◽  
Hideto Matsui ◽  
Masashi Noda ◽  
Shogo Kasuda ◽  
Noritaka Yada ◽  
...  
Keyword(s):  
Blood Flow ◽  
Renal Function ◽  
Renal Blood Flow ◽  
Von Willebrand Factor ◽  
Ischemia Reperfusion ◽  
Kidney Injury ◽  
Acute Ischemia ◽  
Functional Regulation ◽  
Von Willebrand ◽  
Willebrand Factor

Abstract Acute kidney injury (AKI), an abrupt loss of renal function, is often seen in clinical settings and may become fatal. In addition to its hemostatic functions, von Willebrand factor (VWF) is known to play a role in cross-talk between inflammation and thrombosis. We hypothesized that VWF may be involved in the pathophysiology of AKI, major causes of which include insufficient renal circulation or inflammatory cell infiltration in the kidney. To test this hypothesis, we studied the role of VWF in AKI using a mouse model of acute ischemia-reperfusion (I/R) kidney injury. We analyzed renal function and blood flow in VWF-gene deleted (knock-out; KO) mice. The functional regulation of VWF by ADAMTS13 or a function-blocking anti-VWF antibody was also evaluated in this pathological condition. Greater renal blood flow and lower serum creatinine were observed after reperfusion in VWF-KO mice compared with wild-type (WT) mice. Histological analysis also revealed a significantly lower degree of tubular damage and neutrophil infiltration in kidney tissues of VWF-KO mice. Both human recombinant ADAMTS13 and a function-blocking anti-VWF antibody significantly improved renal blood flow, renal function and histological findings in WT mice. Our results indicate that VWF plays a role in the pathogenesis of AKI. Proper functional regulation of VWF may improve the microcirculation and vessel function in the kidney, suggesting a novel therapeutic option against AKI.

scholarly journals P0557HYPERBARIC OXYGEN PRECONDITIONING INCREASES HEME OXYGENASE 1 EXPRESSION IN KIDNEY TISSUE AND IMPROVES KIDNEY FUNCTION IN SPONTANEOUSLY HYPERTENSIVE RATS WITH ISCHEMIC ACUTE KIDNEY INJURY

2020 ◽  
Vol 35 (Supplement_3) ◽  
Author(s):  
Milan Ivanov ◽  
Zoran Miloradovic ◽  
Nevena Mihailovic-Stanojevic ◽  
Djurdjica Jovovic ◽  
Danijela Karanovic ◽  
...  
Keyword(s):  
Acute Kidney Injury ◽  
Kidney Function ◽  
Ischemia Reperfusion ◽  
Kidney Tissue ◽  
Kidney Injury ◽  
Treated Group ◽  
Control Group ◽  
Heme Oxygenase 1 ◽  
Hypertensive Rats ◽  
Spontaneously Hypertensive

Abstract Background and Aims Renal ischemia–reperfusion (RIR) injury is one of the factors in the development of acute kidney injury (AKI). AKI is multifactorially caused, but the mechanism of pathogenesis and development of this disease is still incompletely defined. AKI is characterized by the sudden appearance, rapid progression of disease and very uncertain and often fatal outcome. Heme oxygenase-1 (HO-1) is a cytoprotective enzyme that catalyzes the breakdown of heme to biliverdin, carbon monoxide, and iron. HO-1 is now recognized as a protection factor in acute kidney injury. The aim of this study was to determine the effect of preconditioning with hyperbaric oxygen (HBO) on HO-1 expression in kidney tissue and kidney function in spontaneously hypertensive rats (SHR) during kidney ischemia–reperfusion injury. Method An experiment was performed in anesthetized, adult six-month-old male SHR. The right kidney was removed and the renal ischemia was performed by clamping the left renal artery for 40 minutes. SHR were randomly selected in three experimental groups: sham operated group (SHAM; n=7); AKI control group (AKI; n=9); and AKI group with HBO (AKI+HBO; n=9). Treated group were placed into experimental HBO chambers and exposed to pure oxygen, twice a day (in a 12 hour period, 8AM and 8 PM) for two consecutive days in the following manner: 10 minutes slow compression, 2.026 bar for 60 minutes, 10 minutes slow decompression. Mean arterial pressure (MAP) and HO-1 expression in kidney tissue were measured 24h after reperfusion. Clearance of creatinine (CCr), urea (CUr) and phosphate (CPh) were calculated 24h after reperfusion. Results After AKI induction reduction of blood pressure was recorded in both groups with AKI. Preconditioning with HBO significantly improved kidney function in rats with AKI compared to control group. HO-1 expression in kidney tissue was significantly higher in the treated group (p&lt;0,01) compared to SHAM and AKI control group. Conclusion Our results suggest that HBO treatment improves kidney function in the AKI+HBO vs. AKI control group. This implies that increased level of HO-1 due to preconditioning with hyperbaric oxygen may have beneficial effects on kidney function, and potentially protective effect in an ischemic model of AKI with hypertension.

scholarly journals Urinary Cyclophilin A as Marker of Tubular Cell Death and Kidney Injury

Biomedicines ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 217
Author(s):  
Ramio Cabello ◽  
Miguel Fontecha-Barriuso ◽  
Diego Martin-Sanchez ◽  
Ana M. Lopez-Diaz ◽  
Susana Carrasco ◽  
...  
Keyword(s):  
Cell Death ◽  
Kidney Function ◽  
Ischemia Reperfusion ◽  
Kidney Injury ◽  
Cyclophilin A ◽  
Tubular Cell ◽  
Tubular Cells ◽  
Clinical Biomarkers ◽  
Potential Marker ◽  
Potential Biomarker

Background: Despite the term acute kidney injury (AKI), clinical biomarkers for AKI reflect function rather than injury and independent markers of injury are needed. Tubular cell death, including necroptotic cell death, is a key feature of AKI. Cyclophilin A (CypA) is an intracellular protein that has been reported to be released during necroptosis. We have now explored CypA as a potential marker for kidney injury in cultured tubular cells and in clinical settings of ischemia-reperfusion injury (IRI), characterized by limitations of current diagnostic criteria for AKI. Methods: CypA was analyzed in cultured human and murine proximal tubular epithelial cells exposed to chemical hypoxia, hypoxia/reoxygenation (H/R) or other cell death (apoptosis, necroptosis, ferroptosis) inducers. Urinary levels of CypA (uCypA) were analyzed in patients after nephron sparing surgery (NSS) in which the contralateral kidney is not disturbed and kidney grafts with initial function. Results: Intracellular CypA remained unchanged while supernatant CypA increased in parallel to cell death induction. uCypA levels were higher in NSS patients with renal artery clamping (that is, with NSS-IRI) than in no clamping (NSS-no IRI), and in kidney transplantation (KT) recipients (KT-IRI) even in the presence of preserved or improving kidney function, while this was not the case for urinary Neutrophil gelatinase-associated lipocalin (NGAL). Furthermore, higher uCypA levels in NSS patients were associated with longer surgery duration and the incidence of AKI increased from 10% when using serum creatinine (sCr) or urinary output criteria to 36% when using high uCypA levels in NNS clamping patients. Conclusions: CypA is released by kidney tubular cells during different forms of cell death, and uCypA increased during IRI-induced clinical kidney injury independently from kidney function parameters. Thus, uCypA is a potential biomarker of kidney injury, which is independent from decreased kidney function.

scholarly journals Inhibition of 15-PGDH prevents ischemic renal injury by the PGE2/EP4 signaling pathway mediating vasodilation, increased renal blood flow, and increased adenosine/A2A receptors

2020 ◽  
Vol 319 (6) ◽  
pp. F1054-F1066
Author(s):  
Hye Jung Kim ◽  
Sun-Hee Kim ◽  
Minjung Kim ◽  
HyungJoo Baik ◽  
Seok Ju Park ◽  
...  
Keyword(s):  
Blood Flow ◽  
Renal Blood Flow ◽  
Renal Injury ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
High Mobility ◽  
Kidney Injury ◽  
Clinical Problem ◽  
Protective Effects

In the present study, we demonstrated the marked activity of SW033291, an inhibitor of 15-hydoxyprostaglandin dehydrogenase (15-PGDH), in preventing acute kidney injury (AKI) in a murine model of ischemia-reperfusion injury. AKI due to ischemic injury represents a significant clinical problem. PGE2 is vasodilatory in the kidney, but it is rapidly degraded in vivo due to catabolism by 15-PGDH. We investigated the potential of SW033291, a potent and specific 15-PGDH inhibitor, as prophylactic treatment for ischemic AKI. Prophylactic administration of SW033291 significantly increased renal tissue PGE2 levels and increased post-AKI renal blood flow and renal arteriole area. In parallel, prophylactic SW033291 decreased post-AKI renal morphology injury scores and tubular apoptosis and markedly reduced biomarkers of renal injury that included blood urea nitrogen, creatinine, neutrophil gelatinase-associated lipocalin, and kidney injury molecule-1. Prophylactic SW033291 also reduced post-AKI induction of proinflammatory cytokines, high-mobility group box 1, and malondialdehyde. Protective effects of SW033291 were mediated by PGE2 signaling, as they could be blocked by pharmacological inhibition of PGE2 synthesis. Consistent with activation of PGE2 signaling, SW033291 induced renal levels of both EP4 receptors and cAMP, along with other vasodilatory effectors, including AMP, adenosine, and the adenosine A2A receptor. The protective effects of SW0333291 could largely be achieved with a single prophylactic dose of the drug. Inhibition of 15-PGDH may thus represent a novel strategy for prophylaxis of ischemic AKI in multiple clinical settings, including renal transplantation and cardiovascular surgery.

Vasculotropic, paracrine actions of infused mesenchymal stem cells are important to the recovery from acute kidney injury

2007 ◽  
Vol 292 (5) ◽  
pp. F1626-F1635 ◽  
Author(s):  
Florian Tögel ◽  
Kathleen Weiss ◽  
Ying Yang ◽  
Zhuma Hu ◽  
Ping Zhang ◽  
...  
Keyword(s):  
Stem Cells ◽  
Acute Kidney Injury ◽  
Blood Flow ◽  
Mesenchymal Stem Cells ◽  
Conditioned Medium ◽  
Expression Profiles ◽  
Ischemia Reperfusion ◽  
Kidney Injury ◽  
Cell Phenotype ◽  
Paracrine Actions

Acute kidney injury (AKI) is a major clinical problem in which a critical vascular, pathophysiological component is recognized. We demonstrated previously that mesenchymal stem cells (MSC), unlike fibroblasts, are significantly renoprotective after ischemia-reperfusion injury and concluded that this renoprotection is mediated primarily by paracrine mechanisms. In this study, we investigated whether MSC possess vasculoprotective activity that may contribute, at least in part, to an improved outcome after ischemia-reperfusion AKI. MSC-conditioned medium contains VEGF, HGF, and IGF-1 and augments aortic endothelial cell (EC) growth and survival, a response not observed with fibroblast-conditioned medium. MSC and EC share vasculotropic gene expression profiles, as both form capillary tubes in vitro on Matrigel alone or in cooperation without fusion. MSC undergo differentiation into an endothelial-like cell phenotype in culture and develop into vascular structures in vivo. Infused MSC were readily detected in the kidney early after reflow but were only rarely engrafted at 1 wk post-AKI. MSC attached in the renal microvascular circulation significantly decreased apoptosis of adjacent cells. Infusion of MSC immediately after reflow in severe ischemia-reperfusion AKI did not improve renal blood flow, renovascular resistance, or outer cortical blood flow. These data demonstrate that the unique vasculotropic, paracrine actions elicited by MSC play a significant renoprotective role after AKI, further demonstrating that cell therapy has promise as a novel intervention in AKI.

Reactive oxygen metabolite scavengers decrease functional coronary microvascular injury due to ischemia-reperfusion

1991 ◽  
Vol 260 (1) ◽  
pp. H42-H49
Author(s):  
I. M. Dauber ◽  
E. J. Lesnefsky ◽  
K. M. VanBenthuysen ◽  
J. V. Weil ◽  
L. D. Horwitz
Keyword(s):  
Blood Flow ◽  
Vascular Function ◽  
Ischemia Reperfusion ◽  
Reactive Oxygen ◽  
Microvascular Dysfunction ◽  
Regional Myocardial Blood Flow ◽  
Coronary Microvascular Dysfunction ◽  
Reactive Oxygen Metabolites ◽  
Reactive Oxygen Metabolite ◽  
Microvascular Injury

The role of reactive oxygen metabolites in ischemia-reperfusion coronary microvascular injury is unclear. To investigate this problem, we tested the effects of the reactive oxygen metabolite scavengers superoxide dismutase (SOD) and dimethylthiourea (DMTU) on ischemia-reperfusion-induced coronary microvascular dysfunction. As an index of vascular function, we assessed microvascular permeability with a double radioisotope protein leak index (PLI) method. Anesthetized dogs underwent 60 min of ischemia via left anterior descending (LAD) occlusion followed by 60 min of reperfusion. Untreated animals (n = 7) received saline. SOD-treated animals (n = 6) received 140 U.kg-1.min-1 (6.6 mg.kg-1.min-1) bovine SOD throughout ischemia and reperfusion. DMTU-treated animals (n = 5) received a 500 mg/kg bolus 30 min before ischemia. At the beginning of reperfusion, radiolabeled autologous protein (113mIn transferrin) and red blood cells (99mTc) were given intravenously for the assessment of permeability. In untreated dogs, ischemia-reperfusion increased the PLI of ischemic (flow less than 20 ml.min-1.100 g-1) myocardium more than threefold compared with that of nonischemic (flow greater than 100 ml.min-1.100 g-1) myocardium (ischemic-to-nonischemic PLI ratio = 3.49 +/- 0.48). SOD reduced the PLI of ischemic myocardium by 45% and DMTU reduced it by 66% (PLI = 9.25 +/- 1.30, 5.04 +/- 1.18, and 3.16 +/- 0.94, untreated, SOD, and DMTU, respectively). The PLI was increased proportional to the regional severity of ischemic blood flow. Both SOD and DMTU reduced the increase in protein leak at all levels of regional ischemic blood flow. Neither SOD nor DMTU increased regional myocardial blood flow to the occluded LAD zone.(ABSTRACT TRUNCATED AT 250 WORDS)

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