A multi-domain shear-stress dependent diffusive model of cell transport-aided dialysis: analysis and simulation

<abstract>Kidney dialysis is the most widespread treatment method for end-stage renal disease, a debilitating health condition common in industrialized societies. While ubiquitous, kidney dialysis suffers from an inability to remove larger toxins, resulting in a gradual buildup of these toxins in dialysis patients, ultimately leading to further health complications. To improve dialysis, hollow fibers incorporating a cell-monolayer with cultured kidney cells have been proposed; however, the design of such a fiber is nontrivial. In particular, the effects of fluid wall-shear stress have an important influence on the ability of the cell layer to transport toxins. In the present work, we introduce a model for cell-transport aided dialysis, incorporating the effects of the shear stress. We analyze the model mathematically and establish its well-posedness. We then present a series of numerical results, which suggest that a hollow-fiber design with a wavy profile may increase the efficiency of the dialysis treatment. We investigate numerically the shape of the wavy channel to maximize the toxin clearance. These results demonstrate the potential for the use of computational models in the study and advancement of renal therapies.</abstract>

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L-carnosine and its Derivatives as New Therapeutic Agents for the Prevention and Treatment of Vascular Complications of Diabetes

Current Medicinal Chemistry ◽

10.2174/0929867326666190711102718 ◽

2020 ◽

Vol 27 (11) ◽

pp. 1744-1763 ◽

Cited By ~ 5

Author(s):

Stefano Menini ◽

Carla Iacobini ◽

Claudia Blasetti Fantauzzi ◽

Giuseppe Pugliese

Keyword(s):

Diabetic Nephropathy ◽

Life Quality ◽

Vascular Complications ◽

Carbonyl Stress ◽

Complications Of Diabetes ◽

Diabetic Vascular Complications ◽

Reactive Carbonyl Species ◽

Stage Renal Disease ◽

Stress Dependent ◽

End Stage

Vascular complications are among the most serious manifestations of diabetes. Atherosclerosis is the main cause of reduced life quality and expectancy in diabetics, whereas diabetic nephropathy and retinopathy are the most common causes of end-stage renal disease and blindness. An effective therapeutic approach to prevent vascular complications should counteract the mechanisms of injury. Among them, the toxic effects of Advanced Glycation (AGEs) and Lipoxidation (ALEs) end-products are well-recognized contributors to these sequelae. L-carnosine (β-alanyl-Lhistidine) acts as a quencher of the AGE/ALE precursors Reactive Carbonyl Species (RCS), which are highly reactive aldehydes derived from oxidative and non-oxidative modifications of sugars and lipids. Consistently, L-carnosine was found to be effective in several disease models in which glyco/lipoxidation plays a central pathogenic role. Unfortunately, in humans, L-carnosine is rapidly inactivated by serum carnosinase. Therefore, the search for carnosinase-resistant derivatives of Lcarnosine represents a suitable strategy against carbonyl stress-dependent disorders, particularly diabetic vascular complications. In this review, we present and discuss available data on the efficacy of L-carnosine and its derivatives in preventing vascular complications in rodent models of diabetes and metabolic syndrome. We also discuss genetic findings providing evidence for the involvement of the carnosinase/L-carnosine system in the risk of developing diabetic nephropathy and for preferring the use of carnosinase-resistant compounds in human disease. The availability of therapeutic strategies capable to prevent both long-term glucose toxicity, resulting from insufficient glucoselowering therapy, and lipotoxicity may help reduce the clinical and economic burden of vascular complications of diabetes and related metabolic disorders.

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In Vivo Shear Stress Determines Circulating Levels of Endothelial Microparticles in End-Stage Renal Disease

Hypertension ◽

10.1161/01.hyp.0000259667.22309.df ◽

2007 ◽

Vol 49 (4) ◽

pp. 902-908 ◽

Cited By ~ 113

Author(s):

Chantal M. Boulanger ◽

Nicolas Amabile ◽

Alain P. Guérin ◽

Bruno Pannier ◽

Aurélie S. Leroyer ◽

...

Keyword(s):

Shear Stress ◽

Renal Disease ◽

End Stage Renal Disease ◽

Endothelial Microparticles ◽

Stage Renal Disease ◽

End Stage ◽

Circulating Levels

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Predicting the Hermeticity of Compression Seals in Microchannel Hemodialysers

Volume 1: Materials; Micro and Nano Technologies; Properties, Applications and Systems; Sustainable Manufacturing ◽

10.1115/msec2014-3941 ◽

2014 ◽

Author(s):

Brian K. Paul ◽

Dustin K. Ward

Keyword(s):

Mass Transfer ◽

Patient Outcomes ◽

End Stage Renal Disease ◽

Limiting Factor ◽

Home Hemodialysis ◽

Kidney Dialysis ◽

Medical Facilities ◽

Stage Renal Disease ◽

End Stage ◽

The Cost

Most end stage renal disease patients receive kidney hemodialysis three to four times per week at central medical facilities. At-home kidney dialysis increases the convenience and frequency of hemodialysis treatments which has been shown to produce better patient outcomes. One limiting factor in realizing home hemodialysis treatments is the cost of the hemodialyser. Microchannel hemodialysers produced using compression sealing techniques show promise for reducing the size and cost of hemodialysers. Challenges include the use of a 25 μm thick elastoviscoplastic mass transfer membrane for gasketing. This paper provides a framework for predicting the hermeticity of these compression seals. The mechanical properties of a Gambro AN69ST membrane are determined and used to establish limits on the dimensional tolerances of the polycarbonate laminae containing sealing boss used to seal the hemodialyser. The resulting methods are applied to the fabrication of a hemodialysis device showing constraints on the scaling of this method to larger device sizes. The resulting hemodialysis device is used to perform urea mass transfer experiments without leakage.

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The Hermeticity of Compression Seals in Microchannel Hemodialyzers

Journal of Micro and Nano-Manufacturing ◽

10.1115/1.4027778 ◽

2014 ◽

Vol 2 (3) ◽

Cited By ~ 3

Author(s):

Brian K. Paul ◽

Dustin K. Ward

Keyword(s):

Mass Transfer ◽

Patient Outcomes ◽

End Stage Renal Disease ◽

Limiting Factor ◽

Home Hemodialysis ◽

Kidney Dialysis ◽

Medical Facilities ◽

Stage Renal Disease ◽

End Stage ◽

The Cost

Most end stage renal disease patients receive kidney hemodialysis three to four times per week at central medical facilities. At-home kidney dialysis increases the convenience and frequency of hemodialysis treatments which has been shown to produce better patient outcomes. One limiting factor in realizing home hemodialysis treatments is the cost of the hemodialyzer. Microchannel hemodialyzers produced using compression sealing techniques show promise for reducing the size and cost of hemodialyzers. Challenges include the use of a 25 μm thick elastoviscoplastic (EVP) mass transfer membrane for gasketing. This paper provides a framework for understanding the hermeticity of these compression seals. The mechanical properties of a Gambro AN69ST membrane are determined and used to establish limits on the dimensional tolerances of the polycarbonate (PC) laminae containing sealing bosses used to seal the hemodialyzer. The resulting methods are applied to the fabrication of a hemodialysis device showing constraints on the scaling of this method to larger device sizes. The resulting hemodialysis device is used to perform urea mass transfer experiments without leakage.

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Incomplete Restoration of Homeostatic Shear Stress Within Arteriovenous Fistulae

ASME 2012 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2012-80458 ◽

2012 ◽

Cited By ~ 1

Author(s):

Patrick M. McGah ◽

James J. Riley ◽

Alberto Aliseda ◽

Daniel F. Leotta ◽

Kirk W. Beach

Keyword(s):

Shear Stress ◽

Peripheral Circulation ◽

Shear Stresses ◽

Dialysis Access ◽

Venous Flow ◽

Arteriovenous Fistulae ◽

Flow Rates ◽

Stage Renal Disease ◽

End Stage ◽

Low Shear

Arteriovenous fistulae are created surgically to provide an adequate access for dialysis in patients with End-Stage Renal Disease (ESRD). Producing an autogenous shunt linking an artery and a vein in the peripheral circulation bypasses the high resistance capillary bed in order to provide the necessary flow rates at sites easily accessible for dialysis. In successful fistulae, venous flow rates can easily exceed 1000 mL/min. It has long been recognized that the hemodynamics constitute the primary external influence on the remodeling process [1]; The high flow rate, together with the exposure of the venous tissue to the high arterial pressure, leads to a rapid process of wall remodeling that may end in a mature access or in failure. Recent hemodynamic simulations [2,3] have computed very high viscous wall shear stresses within fistulae; Stresses > 15Pa have been reported which are much greater than what is typically considered normal (i.e. homeostatic, ≈ 1Pa). Both sustained high shear and sustained low shear have been hypothesized to cause pathological venous remodeling (i.e. intimal hyperplasia) which causes stenoses and threatens fistula patency. The role of high vs. low shear stress in effecting patency remains unclear. Given the high failure rate of dialysis access sites (up to 50% require surgical revision within one year [4]), understanding the dynamics of blood flow within the fistula is a necessary step in understanding the remodeling, and ultimately, in improving clinical outcomes.

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Technologies and Health Inequities

Annual Review of Sociology ◽

10.1146/annurev-soc-121919-054802 ◽

2020 ◽

Vol 46 (1) ◽

pp. 583-602

Author(s):

Stefan Timmermans ◽

Rebecca Kaufman

Keyword(s):

Individualized Medicine ◽

Health Inequities ◽

Specific Design ◽

Kidney Dialysis ◽

Health Technologies ◽

Advanced Technologies ◽

Fundamental Causes ◽

Practice Approach ◽

Stage Renal Disease ◽

End Stage

Health technologies aim to improve individual and population health, but they may also exacerbate health disparities. Focusing on the specific design features of technologies, their availability, and their use, we present a conceptual framework to examine how health technologies may benefit some groups more than others by combining the theory of fundamental causes with a technology-in-practice approach. We examine three classes of technologies that have been associated with health inequities: once-advanced technologies such as kidney dialysis and transplantation for end-stage renal disease, which have been plagued by issues of scarcity and fair distribution, generating racial disparities; the highly anticipated precision medicine promising to change the focus from population to individualized medicine; and digital technologies, which may herald a democratization of health care.

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PROBABILITY ESTIMATION ON THE RISK OF MORTALITY OF PATIENTS WITH END-STAGE RENAL DISEASE

International Journal of Pharmacy and Pharmaceutical Sciences ◽

10.22159/ijpps.2016v8s2.15208 ◽

2016 ◽

Vol 8 (2) ◽

pp. 1 ◽

Cited By ~ 1

Author(s):

Jackie D. Urrutia ◽

Jaya C. De Guzman ◽

Aaron Vito M. Baygan ◽

Edcon B. Baccay ◽

Lincoln A. Bautista

Keyword(s):

Cardiovascular Disease ◽

Renal Disease ◽

End Stage Renal Disease ◽

Esrd Patient ◽

Health Condition ◽

The Philippines ◽

Pulmonary Congestion ◽

Risk Of Mortality ◽

Stage Renal Disease ◽

End Stage

The kidneys perform life-maintaining functions like monitoring and regulating body fluids. These excrete excess fluids from the body and retain the substances necessary for the body’s continuing function. If the kidneys malfunction, it may cause some kidney complications that could lead to End-Stage Renal Disease (ESRD) or worst, it may lead to death. End-Stage Renal Disease (ESRD) or 5th stage chronic kidney failure is a growing health condition problem that continues to rise in the Philippines. Kidney Diseases especially End Stage Renal Diseases is the 7th leading cause of death in the country. Using Logistic Regression analysis, this study analyzed the record data such as the age, gender and the complications of 247 patients with Pulmonary Congestion and/or Cardiovascular disease diagnosed with ESRD at M. V. Makabali Memorial Hospital from the year 2008-2013. The present study was undertaken to identify the risk factors which causes to increase the death probability of an ESRD patient. The research concluded that pulmonary congestion and cardiovascular disease are significant factors that increase the patients’ probability to encounter death. Moreover, an ESRD patient with cardiovascular disease has a higher chance to encounter death with a probability of 68.52% than an ESRD patient with pulmonary congestions with a probability of 57.79%. The results also revealed that if a patient suffered from both complications, he/she has a higher risk of mortality with a probability of 98.6%. ESRD may not be curable but with the proper management of health condition and maintaining a healthy lifestyle, it can be prevented and possibly could lessen the risk of death.

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Exteriorizing the Outer Cuff to Treat Intractable Exit Site Infection and Tunnel Infection in Peritoneal Dialysis Cases: A Single Institute Experience

Surgical Case Reports ◽

10.31487/j.scr.2020.03.08 ◽

2020 ◽

pp. 1-3

Author(s):

Tsung I Hung ◽

Ching Shya Yong ◽

Juiting Chang ◽

Tsung I Hung ◽

Wei Ting Chang ◽

...

Keyword(s):

Peritoneal Dialysis ◽

Renal Disease ◽

End Stage Renal Disease ◽

Treatment Method ◽

Residual Renal Function ◽

Site Infection ◽

Exit Site ◽

Exit Site Infection ◽

Stage Renal Disease ◽

End Stage

Peritoneal dialysis (PD) is an important treatment method for patients with end stage renal disease. Since its introduction in 1975, clinical studies have shown that PD can improve patient survival, retain residual renal function, and lower the risk of infection. It can also reduce financial stress in the growing population with end stage renal disease. However, PD has limitations, mainly technique failures. Of these, catheterrelated infection is a major cause of catheter failure in PD. We reviewed the medical records of 986 PD patients from 2008 to 2018 at our hospital. The patients with intractable tunnel and exit site infection received exteriorization of the outer cuff and cuff shaving. The favourable outcomes observed recommend this treatment for PD patients whose catheter infection is not well controlled.

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