The Interplay Between Human Leukocyte Antigen Antibody Profile and COVID-19 Vaccination in Waitlisted Renal Transplant Patients.

CONTEXT.­: Mass COVID-19 vaccination is mandated in vulnerable populations in our renal transplant waitlist cohort. However, the anti-human leukocyte antigen (anti-HLA) profile after COVID-19 vaccination is controversial, and the side effects are yet to be discerned. OBJECTIVE.­: To evaluate the status of HLA antibodies in waitlist renal transplant patients before and 3 weeks after each vaccination and if comorbidities are associated with the HLA antibody profile. DESIGN.­: A total of 59 waitlisted kidney transplant patients were included in this study. The anti-HLA antibodies were analyzed before and 6 months after their last COVID-19 vaccination. The mean fluorescence intensity change in the anti-HLA antibody levels was used to classify patients into 3 groups: high inducers, low inducers, and noninducers. RESULTS.­: There were significant HLA antibody profile changes after COVID-19 vaccination, showing 21 antibodies generated against HLA class I antigens and 7 against HLA class II antigens to their baseline. Compared with the noninducers, the high and low inducers showed a higher prevalence of COVID-19 infection, COVID-19 vaccine type, and background hypertension history. CONCLUSIONS.­: Our data suggest that COVID-19 vaccination propagates anti-HLA class I and II antibodies for waitlisted renal transplant patients. The clinical significance of these antibodies needs further study. Furthermore, comorbidities, such as history of COVID-19 infection and hypertension, supplemented this effect. Anti-HLA antibody monitoring may be warranted in vaccinated, waitlisted renal transplant patients with COVID-19 vaccinations, and a history of COVID-19 infection or hypertension.

Heparin-Immobilized Polyethersulfone for Hemocompatibility Enhancement of Dialysis Membrane: In Situ Synchrotron Imaging, Experimental, and Ex Vivo Studies.

The goal of the current study is to enhance the hemocompatibility of polyethersulfone (PES) membranes using heparin immobilization. Heparin was immobilized covalently and via electrostatic interaction with the positively charged PES surface (pseudo-zwitterionic (pZW) complex) to investigate the influence of each method on the membrane hemocompatibility. In situ synchrotron radiation micro-computed tomography (SR-µCT) imaging, available at the Canadian Light Source (CLS), was used to critically assess the fibrinogen adsorption to the newly synthesized membranes qualitatively and quantitatively using an innovative synchrotron-based X-ray tomography technique. The surface roughness of the synthesized membranes was tested using atomic force microscopy (AFM) analysis. The membrane hemocompatibility was examined through the ex vivo clinical interaction of the membranes with patients' blood to investigate the released inflammatory biomarkers (C5a, IL-1α, IL-1ß, IL-6, vWF, and C5b-9). The presence and quantitative analysis of a stable hydration layer were assessed with DSC analysis. Surface modification resulted in reduced surface roughness of the heparin-PES membrane. Both types of heparin immobilization on the PES membrane surface resulted in a decrease in the absolute membrane surface charge from -60 mV (unmodified PES) to -13 mV for the pZW complex and -9.16 mV for the covalently attached heparin, respectively. The loss of human serum fibrinogen (FB) was investigated using UV analysis. The PES membrane modified with the heparin pseudo-ZW complex showed increased FB retention (90.5%), while the unmodified PES membrane and the heparin covalently attached PES membrane exhibited approximately the same level of FB retention (81.3% and 79.8%, respectively). A DSC analysis revealed an improvement in the content of the hydration layer (32% of non-freezable water) for the heparin-coated membranes compared to the unmodified PES membrane (2.84%). An SR-µCT analysis showed that the method of heparin immobilization significantly affects FB adsorption distribution across the membrane thickness. A quantitative analysis using SR-µCT showed that when heparin is attached covalently, FB tends to be deposited inside the membrane pores at the top (layer index 0-40) membrane regions, although its content peak distribution shifted to the membrane surface, whereas the unmodified PES membrane holds 90% of FB in the middle (layer index 40-60) of the membrane. The ex vivo hemocompatibility study indicates an improvement in reducing the von Willebrand factor (vWF) for the heparin pseudo-ZW PES membrane compared to the covalently attached heparin and the untreated PES.

In-situ synchrotron imaging, experimental, and computational investigations on the efficiency of Trametes versicolor laccase on detoxification of P-Cresyl Sulfate (PCS) Protein Bound Uremic Toxin (PBUT).

Protein bound uremic toxins (PBUTs) are small substances binding to larger proteins, mostly human serum albumin (HSA), and are challenging to remove by hemodialysis (HD). Among different classes of PBUTs, p-cresyl sulfate (PCS) is the most widely used marker molecule and major toxin, as 95 % is bound to HSA. PCS has a pro-inflammatory effect and increases both the uremia symptom score and multiple pathophysiological activities. High-flux HD to clear PCS leads to serious loss of HSA, which results in a high mortality rate. The goal of the present study is to investigate the efficacy of PCS detoxification in serum of HD patients using a biocompatible laccase enzyme from Trametes versicolor. Molecular docking was used to gain an in-depth understanding of the interactions between PCS and the laccase to identify the functional group(s) responsible for ligand-protein receptor interactions. UV-Vis spectroscopy and gas chromatography-mass spectrometry (GC-MS) were used to assess the detoxification of PCS. GC-MS was used to identify the detoxification byproducts and their toxicity was assessed using docking commutations. In situ synchrotron radiation micro-computed tomography (SR-µCT) imaging available at the Canadian Light Source (CLS) was conducted to assess HSA binding with PCS before and after detoxification with laccase and undertake the corresponding quantitative analysis. GC-MS analyses confirmed the detoxification of PCS with laccase at a concentration of 500 mg/L. The potential pathway of PCS detoxification in the presence of the laccase was identified. Increasing laccase concentration led to the formation of m-cresol, as indicated by the corresponding absorption in the UV-Vis spectra and a sharp peak on the GC-MS spectra. Our analysis provides insight into the general features of PCS binding on Sudlow site II, as well as insights into PCS detoxification product interactions. The average affinity energy for detoxification products was lower than that of PCS. Even though some byproducts showed potential toxicity, the level was lower than for PCS based on toxicity indexes (e.g., LD50/LC50, carcinogenicity, neurotoxicity, mutagenicity). In addition, these small compounds can also be more easily removed by HD compared to PCS. SR-µCT quantitative analysis showed adhesion of the HSA to a significant reduced extent in the presence of the laccase enzyme in bottom sections of the polyarylethersulfone (PAES) clinical HD membrane tested. Overall, this study opens new frontiers for PCS detoxification.

In-situ synchrotron quantitative analysis of competitive adsorption tendency of human serum proteins on polyether sulfone clinical hemodialysis membrane.

Comprehensive understanding of protein adsorption phenomenon on membrane surface during hemodialysis (HD) is one of the key moments for development of hemocompatible HD membrane. Though many mechanisms and kinetics of protein adsorption on some surface have been studied, we are still far away from complete understanding and control of this process, which results in a series of biochemical reactions that causes severe complications with health and even the death among HD patients. The aim of this study is to conduct quantitative analysis of competitive adsorption tendency of human serum protein on polyether sulfone (PES) clinical dialysis membrane. In situ synchrotron radiation micro-computed tomography (SR-µCT) imaging available at the Canadian Light Source (CLS) was conducted to assess human serum proteinbinding and undertake the corresponding quantitative analysis.The competitive adsorption of Human protein albumin (HSA), fibrinogen (FB) and transferrin (TRF) were tested from single and multiple protein solution. Furthermore, in-vitro human serum protein adsorption on clinical dialyzers was investigated using UV-Visible to confirm the competitive adsorption tendency. Results showed that when proteins were adsorbed from their mixture, FB content (among proteins) in the adsorbed layer increased from 3.6% mass (content in the initial solution) to 18% mass and 12%, in case of in situ quantitative and invitro analysis, respectively. The increase in FB content was accompanied by the decrease in the HSA content, while TRF remained on approximately on the same level for both cases. Overall, the percentage of HSA adsorption ratio onto the HD membrane has dropped approximately 10 times when HSA was adsorbed in competition with other proteins, compared to the adsorption from single HSA solution. The substitution of HSA with FB was especially noticeable when HSA adsorption from its single solution was compared with the case of the protein mixture. Moreover, SR-µCT has revealed that FB when adsorbed from a protein mixture solution is located predominately in the middle of the membrane, whereas the peak of the distribution is shifted to membrane bottom layers when adsorption from FB single solution takes place. Results showed that HSA FB and TRF adsorption behavior observations are similar on both in-situ small scale and clinical dialyzer of the PES membrane.

Investigation on Human Serum Protein Depositions Inside Polyvinylidene Fluoride-Based Dialysis Membrane Layers Using Synchrotron Radiation Micro-Computed Tomography (SR-µCT).

Hemodialysis (HD) membrane fouling with human serum proteins is a highly undesirable process that results in blood activations with further severe consequences for HD patients. Polyvinylidene fluoride (PVDF) membranes possess a great extent of protein adsorption due to hydrophobic interaction between the membrane surface and non-polar regions of proteins. In this study, a PVDF membrane was modified with a zwitterionic (ZW) polymeric structure based on a poly (maleic anhydride-alt-1-decene), 3-(dimethylamino)-1-propylamine derivative and 1,3-propanesultone. Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), and zeta potential analyses were used to determine the membrane's characteristics. Membrane fouling with human serum proteins (human serum albumin (HSA), fibrinogen (FB), and transferrin (TRF)) was investigated with synchrotron radiation micro-computed tomography (SR-µCT), which allowed us to trace the protein location layer by layer inside the membrane. Both membranes (PVDF and modified PVDF) were detected to possess the preferred FB adsorption due to the Vroman effect, resulting in an increase in FB content in the adsorbed protein compared to FB content in the protein mixture solution. Moreover, FB was shown to only replace HSA, and no significant role of TRF in the Vroman effect was detected; i.e., TRF content was nearly the same both in the adsorbed protein layer and in the protein mixture solution. Surface modification of the PVDF membrane resulted in increased FB adsorption from both the protein mixture and the FB single solution, which is supposed to be due to the presence of an uncompensated negative charge that is located at the COOH group in the ZW polymer.

Pharmacokinetics of apixaban and tacrolimus or cyclosporine in kidney and lung transplant recipients.

Apixaban is frequently used off-label in transplant recipients. However, a potential drug interaction exists with the calcineurin inhibitors. We conducted an open-label drug-drug interaction study to determine the pharmacokinetics of apixaban in lung and kidney transplant recipients who were taking a calcineurin inhibitor. A single dose of apixaban 10 mg was administered orally to kidney and lung transplant recipients maintained on either tacrolimus or cyclosporine, and pharmacokinetic parameters were compared to a reference cohort of 12 healthy subjects who used the same apixaban dose and pharmacokinetic blood sampling. Fourteen participants were enrolled (n = 6 kidney, n = 8 lung), with 10 maintained on tacrolimus and four on cyclosporine. Data from 13 participants was usable. Participants were taking triple therapy immunosuppression and had a mean (SD) of 12 (3) medications. Participants receiving tacrolimus and cyclosporine had area under the plasma concentration-time curve from time zero to infinity (AUC0-inf ) geometric least square means (90% confidence interval [CI]) of 4312 (95% CI 3682, 5049) and 5388 (95% CI 3277, 8858), respectively. Compared to healthy subjects, the associated geometric mean ratios (GMRs) for apixaban maximum plasma concentration (Cmax ), AUC from time zero to the last quantifiable concentration (AUC0-tlast ) and AUC0-inf were 197% (95% CI 153, 295), 244% (95% CI 184, 323), and 224% (95% CI 170, 295) for transplant recipients on tacrolimus. The GMR (90% CI) Cmax , AUC0-tlast , and AUC0-inf of apixaban for patients on cyclosporine were 256% (95% CI 184, 358), 287% (95% CI 198, 415), and 280% (95% CI 195, 401). Kidney and lung transplant recipients receiving tacrolimus had higher apixaban exposure. A similar trend was noted for patients receiving cyclosporine, but additional patients are needed to confirm this interaction. Future studies are needed before apixaban can be safely recommended in this population, and the impact of dose staggering should be investigated. This study highlights the importance of pharmacokinetic studies in actual patient populations.

Influence of UV-irradiation intensity and exposure duration on the hemobiocompatibility enhancement of a novel synthesized phosphobetaine zwitterions polyethersulfone clinical hemodialysis membranes.

To improve the biocompatibility of polyethersulfone (PES) membranes utilized for biomedical hemodialysis (HD) applications, surface grafting with hydrophilic polymers has become a reliable modification strategy. Like most photochemical catalyzed reactions, UV-assisted grafting is distinctly advantageous for inducing permanent surface chemistry, enhancing hydrophilicity, improving morphology, and surface charge of membranes. PES membranes may be hydrophilic and chemically stable; however, they also have low protein-binding capacity and very susceptible to fouling and target analyte binding. In this study, novel zwitterionic polymers (PVP-ZW) have been synthesized by UV-assisted grafting PVP to a phosphobetaine monomer in a reaction involving dimethylamino and dioxaphospholane-2-oxide terminal groups in an NVP monomer solution at varying UV exposure conditions. The highlight of the present study is the investigation of the hemocompatibility of coated PES HD membranes at varying UV exposure conditions with respect to membrane chemistry and morphology and its influence on human serum protein adsorption. A clinical investigation of inflammatory biomarker release from incubated coated membranes within uremic blood samples of HD patients reveals they are weak complement and coagulation activators compared to bare PES membrane. The trend of fibrinogen adsorption on coated PES membranes was observed to increase with reducing UV intensity and exposure duration. Fibrinogen adhesion only increased with roughened membrane surfaces, and this also led to the formation of biological activation pathways hindering biocompatibility. Resistance against fibrinogen absorption on zwitterionic modified PES membrane could be linked with the creation of electrostatically induced neutral zwitterionic PVP-phosphobetaine hydration layer with hydrophilic character. Experimental results are accompanied by spectroscopic and morphological imaging evidence. Zwitterion coated PES membranes (PES-PVP-ZW) fabricated from higher UV intensities through longer exposure durations showed significant presence of surface deformations in the forms of inherent exfoliations due to harsh UV reaction conditions. The zeta potential and surface roughness of coated membranes also played significant role in the fibrinogen adsorption on PES membranes during ultrafiltration.

Hemodialysis biocompatibility mathematical models to predict the inflammatory biomarkers released in dialysis patients based on hemodialysis membrane characteristics and clinical practices.

Chronic kidney disease affects millions of people around the globe and many patients rely on hemodialysis (HD) to survive. HD is associated with undesired life-threatening side effects that are linked to membrane biocompatibility and clinical operating conditions. The present study develops a mathematical model to predict the inflammatory biomarkers released in HD patients based on membrane morphology, chemistry, and interaction affinity. Based on the morphological characteristics of two clinical-grade HD membrane modules (CTA and PAES-PVP) commonly used in Canadian hospitals, a molecular docking study, and the release of inflammatory cytokines during HD and in vitro incubation experiments, we develop five sets of equations that describe the concentration of eight biomarkers (serpin/antithrombin-III, properdin, C5a, 1L-1α, 1L-1ß, C5b-9, IL6, vWF). The equations developed are functions of membrane properties (pore size, roughness, chemical composition, affinity to fibrinogen, and surface charge) and HD operating conditions (blood flow rate, Qb, and treatment time, t). We expand our model based on available clinical data and increase its range of applicability in terms of flow rate and treatment time. We also modify the original equations to expand their range of applicability in terms of membrane materials, allowing the prediction and validation of the inflammatory response of several clinical and synthesized membrane materials. Our affinity-based model solely relies on theoretical values of molecular docking, which can significantly reduce the experimental load related to the development of more biocompatible materials. Our model predictions agree with experimental clinical data and can guide the development of novel materials and support evidence-based membrane synthesis of HD membranes, reducing the need for trial-and-error approaches.

A Randomized Controlled Trial of a Pretransplant Educational Intervention in Kidney Patients.

Poor patient knowledge about transplantation is a significant problem following kidney transplant. A video-based educational intervention was developed to supplement standard education provided by transplant teams. METHODS: A multicenter randomized controlled trial tested the intervention delivered to patients undergoing assessment or waitlisted for kidney transplant. Adult participants were randomized to the control (standard education) or the intervention group, consisting of electronic access to the videos (or digital video disks if no internet) plus standard education. Differences between groups in changes in transplant knowledge (measured by the Kidney Transplant Understanding Tool), education satisfaction, self-efficacy, and quality of life (secondary outcomes) were evaluated by a preintervention and postintervention survey. Video viewing habits were tracked and described for patients in the intervention group. RESULTS: One hundred sixty-two patients were enrolled, with 132 completing both questionnaires (n = 64 intervention and n = 68 control), with similar enrollment from 3 Canadian sites. Video viewing statistics in the complete cases indicated that 78% (50/64) watched the videos, with 70% (45/64) viewing them electronically, while 8% (5/64) received digital video disks and self-reported participation. Baseline knowledge scores in the intent-to-treat population were 55.4 ± 6.5 and 55.7 ± 7.1 in the intervention and control, respectively. The mean knowledge change in the intervention (2.1 ± 3.6) was significantly higher than in the control group (0.8 ± 3.4, P < 0.02). In the per-protocol analysis (patients with objective evidence of watching at least 80% of the videos), the knowledge improvements were 3.4 ± 3.8. Video group participants reported higher satisfaction with education (P < 0.02) and expressed positive comments in open-ended feedback. CONCLUSIONS: Electronic video education in the pretransplant setting improved knowledge and satisfaction.

Protein-bound uremic toxins (PBUTs) in chronic kidney disease (CKD) patients: Production pathway, challenges and recent advances in renal PBUTs clearance.

Uremic toxins, a group of uremic retention solutes with high concentration which their accumulation on the body makes several biological problems, have recently gained a large interest. The importance of this issue more targets patients with compromised kidney function since the presence of these toxins in their bodies contributes to serious illness and death. It is reported that around 14% of people are subjected of CKD's problems. Among different classifications of uremic toxins, protein bound uremic toxins are poorly removed from the body as they tightly bind to proteins like serum albumin. A deeper and closer understanding of methods for removing protein bound uremic toxins and their efficiency is of paramount importance. This article discussed the most critical protein bound uremic toxins from different points of view including their chemistry, binding sites, interactions, and their biological impacts. Concerning the toxicity and high concentration, p-cresyl sulfate (PCS), Indoxyl sulfate (IS), 3-Carboxy-4-methyl-5-propyl-2-furanpropionic acid (CMPF), and Indole- 3-acetic acid (IAA) was chosen to study in this article. Results offered that the functional groups of mentioned PBUTs and the way that they interact with the adsorbent play an important role in finding substances for removal of them. Furthermore, the development of nanoparticle (NPs) for promising biomedical purposes has been explored. However, there is still a need for further investigation to find biocompatible substances focusing on the removal of PBUTs. PBUTs are a unique class of uremic toxins whose renal clearance mechanisms and role in uremic pathophysiology are still unclear. This review outlines the biochemical aspects of PBUT/protein binding in a view to explaining their renal formation to elimination mechanisms; some examples are drawn from routes involving albumin-binding with indoxyl sulphate, p-cresyl sulfate, p-cresyl glucuronide and hippuric acid. We have also highlighted the kinetic behaviors during dialytic removal of PBUTs to address future concerns regarding dialytic therapy.

Biocompatibility enhancement of hemodialysis membranes using a novel zwitterionic copolymer: Experimental, in situ synchrotron imaging, molecular docking, and clinical inflammatory biomarkers investigations.

The aim of the current research study is to conduct a comparative assessment of biocompatibility of zwitterionic-coated polyether sulfone (PES) clinical hemodialysis (HD) membranes using both theoretical and experimental methods. Fibrinogen plays a key role in assessing membrane hemocompatibility since its membrane-surface adsorption triggers several biological reactions, complete thrombosis and embolism. As a result, adsorption of fibrinogen on the untreated PES surface and novel synthesized PES coated with poly 3-((3-(3-carboxy-2,5-dimethyltridecanamido) propyl) dimethylammonio) propane-1-sulfonate as a zwitterion (ZW) was compared. Specifically, the comparison was conducted using in situ synchrotron based micro computed tomography imaging (SR-µCT), Attenuated Total Reflection Fourier Transform Infrared (ATR-FTIR) spectroscopy, and Scanning Electron Microscopy (SEM). The in situ SR-µCT showed that fibrinogen adsorption and membrane fouling were intense on PES membrane surface. However, there was insignificant fouling in the middle layer of zwitterion coated PES membrane (PES-ZW). Moderate shifting of peaks was observed in ATR-FTIR spectra of the adsorbed fibrinogen when compared to the bulk protein spectra, which may be due to the conformational transformations occurring during the adsorption process. The spectral features indicate that PES-ZW surface has a lower adsorption affinity for fibrinogen than that for the PES surface. In this innovative study, the use of molecular modeling docking to evaluate the interaction of fibrinogen active pose with PES-ZW and PES models with the aim of gaining an in depth understanding of the functional group responsible for the interactions was explored. The PES and PES/zwitterion hemodialysis membrane models indicated minimum binding energies with fibrinogen by -6.00 and -6.70 kcal/mol, respectively. Docking studies thus suggest that the membrane's sulfone functional groups play an essential key role during the fibrinogen interaction and adsorption. The HD patients' uremic samples were incubated in vitro with PES and PES-ZW membranes for the inflammatory biomarkers released of Serpin/Antithrombin-III, Properdin, C5a, IL-1α, IL-1ß, TNF-α, and IL6. This study's results emphasize that even though a neutral charge of synthesized novel zwitterion PES, which enhances biocompatibility, the sulfone group still significantly affected the interactions with fibrinogen.

A case study of poly (aryl ether sulfone) hemodialysis membrane interactions with human blood: Molecular dynamics simulation and experimental analyses.

Patients with end-stage renal diseases (ESRD) require specific health cares as the accumulation of toxins due to the lack of kidney functionality would affect their lives. However, the mortality rate is still high due to cardiovascular diseases, socks, etc. A majority of patients with chronic kidney disease (CKD) require hemodialysis services. Blood purifying membranes, as the main component of hemodialysis setups, however, still suffer from lack of optimum biocompatibility, which results in morbidity and mortality of hemodialysis service receiving patients. The goal of the present case study is to have an in-depth understanding of the current blood-hemodialysis membrane interactions occurring during hemodialysis sessions using poly (aryl ether sulfone)-poly (vinyl pyrrolidone) (PAES-PVP) membrane. Attenuated total reflectance-Fourier transmission infrared (ATR-FTIR) spectroscopy, Raman spectroscopy, and solid-state nuclear magnetic resonance (SSNMR) spectroscopy were used to assess the initial chemical structure of the PAES-PVP membrane along with the variations after with the infections with human blood. Furthermore, scanning electron microscopy (SEM) and Transition electron microscopy (TEM) were used to visualize the structural variation of the membrane, blood aggregations, and blood clots on the membrane surface. Besides, Molecular dynamics (MD) simulation was used to assess the interaction of PAES-PVP with major human blood proteins, in terms of interaction energy, which is a novel contribution to the area. The macromolecules (human serum albumin (HSA), human serum transferrin (TRF), and human fibrinogen (HFG)) were chosen from the plasma protein component. These protein structures were chosen based on their different molecular size. Three advanced spectroscopy techniques and two advanced visualization techniques were used for the assessment of the membranes. Spectroscopy studies revealed amine related peak displacement and intensity shifts as indices for attachment of biological species to the polymeric membrane surfaces. Raman peaks around 370, 798, and 1299 cm-1, which experienced significant shifts that were related to carbon-nitrogen and sulfur-oxygen bonds due to protein adhesion. Visualization techniques illustrated blood protein fouling patterns and extracellular vesicles' presence in the pore structures into membranes. The findings highlight the importance of whole structure biocompatibility improvement, rather than only focusing on surface modifications of hemodialysis membranes. Molecular dynamics simulation assessment showed various interaction behaviors for different proteins suggesting molecular weight and active residues of the protein macromolecules play an important role in interacting with polymeric structure. FB had the highest interaction (4,274,749.07 kcal/mol) and binding (10,370.90 kcal/mol) energy with the PAES-PVP structure. TRF owned the lowest interaction energy with respect to its lower molecular weight and fewer active residue count.

Case studies of clinical hemodialysis membranes: influences of membrane morphology and biocompatibility on uremic blood-membrane interactions and inflammatory biomarkers.

End stage renal disease (ESRD) patients depend on hemodialysis (HD) as a life-sustaining treatment, but HD membrane properties play a critical role in blood activation during HD and can lead to severe patient outcomes. This study reports on a series of investigations on the common clinical HD membranes available in Canadian hospitals to explore the key reasons behind their susceptibility to blood activation and unstable cytokine. Clinical HD membranes composed of cellulose triacetate (CTA) and polyvinylpyrrolidone: polyarylethersulfone (PAES: PVP) were thoroughly characterized in terms of morphology and chemical composition. Membrane-surface interactions with uremic blood samples after HD treatment were probed using Fourier Transform Infra-Red (FTIR) and Raman spectroscopic techniques in order to understand changes in chemistry on membrane fibers. In addition, as part of this innovative study, we utilized Molecular Modeling Docking to examine the interactions of human blood proteins and membrane models to gain an in-depth understanding of functional group types responsible for perceived interactions. In-vitro adsorption of fibrinogen on different clinical HD membranes was compared at similar clinical operating conditions. Samples were collected from dialysis patients to ascertain the extent of inflammatory biomarkers released, before, during (30 and 90 min) and after dialysis (4 h). Collected blood samples were analyzed using Luminex assays for the inflammatory biomarkers of Serpin/Antithrombin-III, Properdin, C5a, 1L-1α, 1L-1ß, TNF-α, IL6, and vWF. We have likewise incubated uremic blood in vitro with the two membrane materials to determine the impact that membrane materials pose in favor of activation away from the hydrodynamics influences. The results of our morphological, chemical, spectroscopic, and in vitro incubation analyses indicate that CTA membranes have a smoother surface and higher biocompatibility than PAES: PVP membranes, however, it has smaller pore size distribution, which results in poor clearance of a broad spectrum of uremic toxins. However, the rougher surface and greater hydrophilicity of PAES: PVP membranes increases red blood cell rupture at the membrane surface, which promotes protein adsorption and biochemical cascade reactions. Molecular docking studies indicate sulfone functional groups play an important role in the adsorption of proteins and receptors. PAES: PVP membranes result in slower but greater adsorption of fibrinogen, but are more likely to experience reversible and irreversible fouling as well as backfiltration. Our major finding is that a single dialysis session, even with a more biocompatible membrane such as CTA, increases the levels of complement and inflammation factors, but to a milder extent than dialysis with a PAES membrane.

A surface-enhanced Raman scattering-based approach for rapid and highly sensitive quantitative analysis of 3-carboxy-4-methyl-5-propyl-2-furanpropionate and indole-3-acetic acid in saline, human serum and uremic serum of patients with chronic kidney disease.

3-Carboxy-4-methyl-5-propyl-2-furanpropionate (CMPF) and indole-3-acetic acid (IAA) are critical protein-bound uremic toxins that occur during chronic kidney disease (CKD). This study offers the first reported instance of surface-enhanced Raman scattering (SERS) coupled with an Au nanoparticle substrate for the simple quantification of CMPF and IAA in human serum samples. The detection limits of the CMPF and IAA analysis were estimated to be 0.04 nM (S/N = 3) and 0.05 µM (S/N = 3), respectively. The results demonstrate that the SERS technique is fast-acting and highly sensitive when it comes to the simultaneous and individual quantitative detection of CMPF and IAA in biological samples. We believe that this analytical tool could serve as a very useful method for practical applications during the analysis of CMPF and IAA in the serum and urine of patients at all stages of CKD and of healthy volunteers as well as in various reservoirs.

Randomised controlled trial of a video intervention and behaviour contract to improve medication adherence after renal transplantation: the VECTOR study protocol.

INTRODUCTION: Non-adherence after kidney transplantation contributes to increased rejections, hospitalisations and healthcare expenditures. Although effective adherence interventions are sorely needed, increasing education and support to transplant recipients demands greater use of care providers' time and resources in a healthcare system that is stretched. The objective of this clinical trial is to determine the effectiveness of an electronically delivered video series and adherence behaviour contract on improving medication adherence to immunosuppressant medications. METHODS AND ANALYSIS: A multicentre, parallel arm, randomised controlled trial will be conducted with four sites across North America (Saskatoon, Calgary, Halifax, Chicago). Adult patients will be randomised (1:1) to either the intervention (ie, home-based video education +behaviour contract plus usual care) or usual care alone. De novo transplant recipients will be enrolled prior to their hospital discharge and will be provided with electronic access to the video intervention (immediately) and adherence contract (1 month post-transplant). Follow-up electronic surveys will be provided at 3 and 12 months postenrolment. The primary outcome will be adherence at 12 months post-transplant, as measured by self-report Basel Assessment of Adherence to Immunosuppressive medications and immunosuppressant levels. Secondary outcomes include the difference in knowledge score between the intervention and control in groups (measured by the Kidney Transplant Understanding Tool); differences in self-efficacy (Generalised Self-efficacy Scale), Beliefs of Medicine Questionnaire (BMQ), quality of life (Short Form-12), patient satisfaction and cost utilisation. The study aims to recruit at least 200 participants across participating sites. ETHICS AND DISSEMINATION: Ethical approval was obtained from the University of Saskatchewan Behavioural Ethics Committee (Beh 18-63), and all patients provide informed consent prior to participating. This educational intervention aims to improve information retention and self-efficacy, leading to improved medication adherence after kidney transplantation, at low cost, with little impact to existing healthcare personnel. If proven beneficial, delivery can be easily implemented into standard of care. TRIAL REGISTRATION NUMBER: NCT03540121; Pre-results.

Development and in vitro characterization of chitosan-coated polymeric nanoparticles for oral delivery and sustained release of the immunosuppressant drug mycophenolate mofetil.

OBJECTIVE: To develop an oral sustained release formulation of mycophenolate mofetil (MMF) for once-daily dosing, using chitosan-coated polylactic acid (PLA) or poly(lactic-co-glycolic) acid (PLGA) nanoparticles. The role of polymer molecular weight (MW) and drug to polymer ratio in encapsulation efficiency (EE) and release from the nanoparticles was explored in vitro. METHODS: Nanoparticles were prepared by a single emulsion solvent evaporation method where MMF was encapsulated with PLGA or PLA at various polymer MW and drug: polymer ratios. Subsequently, chitosan was added to create coated cationic particles, also at several chitosan MW grades and drug: polymer ratios. All the formulations were evaluated for mean diameter and polydispersity, EE as well as in vitro drug release. Differential scanning calorimetry (DSC), surface morphology, and in vitro mucin binding of the nanoparticles were performed for further characterization. RESULTS: Two lead formulations comprise MMF: high MW, PLA: medium MW chitosan 1:7:7 (w/w/w), and MMF: high MW, PLGA: high MW chitosan 1:7:7 (w/w/w), which had high EE (94.34% and 75.44%, respectively) and sustained drug release over 12 h with a minimal burst phase. DSC experiments revealed an amorphous form of MMF in the nanoparticle formulations. The surface morphology of the MMF NP showed spherical nanoparticles with minimal visible porosity. The potential for mucoadhesiveness was assessed by changes in zeta potential after incubation of the nanoparticles in mucin. CONCLUSION: Two chitosan-coated nanoparticles formulations of MMF had high EE and a desirable sustained drug release profile in the effort to design a once-daily dosage form for MMF.

Comparison of the effects of standard vs low-dose prolonged-release tacrolimus with or without ACEi/ARB on the histology and function of renal allografts.

Targeting the renin-angiotensin system and optimizing tacrolimus exposure are both postulated to improve outcomes in renal transplant recipients (RTRs) by preventing interstitial fibrosis/tubular atrophy (IF/TA). In this multicenter, prospective, open-label controlled trial, adult de novo RTRs were randomized in a 2 × 2 design to low- vs standard-dose (LOW vs STD) prolonged-release tacrolimus and to angiotensin-converting enzyme inhibitors/angiotensin II receptor 1 blockers (ACEi/ARBs) vs other antihypertensive therapy (OAHT). There were 2 coprimary endpoints: the prevalence of IF/TA at month 6 and at month 24. IF/TA prevalence was similar for LOW vs STD tacrolimus at month 6 (36.8% vs 39.5%; P = .80) and ACEi/ARBs vs OAHT at month 24 (54.8% vs 58.2%; P = .33). IF/TA progression decreased significantly with LOW vs STD tacrolimus at month 24 (mean [SD] change, +0.42 [1.477] vs +1.10 [1.577]; P = .0039). Across the 4 treatment groups, LOW + ACEi/ARB patients exhibited the lowest mean IF/TA change and, compared with LOW + OAHT patients, experienced significantly delayed time to first T cell-mediated rejection. Renal function was stable from month 1 to month 24 in all treatment groups. No unexpected safety findings were detected. Coupled with LOW tacrolimus dosing, ACEi/ARBs appear to reduce IF/TA progression and delay rejection relative to reduced tacrolimus exposure without renin-angiotensin system blockade. ClinicalTrials.gov identifier: NCT00933231.

Contribution of diminished kidney transplant GFR to increased circulating chemokine ligand 27 level.

BACKGROUND: Inflammatory chemokine ligands (CCLs) play an important role in cardiovascular disease and allograft injury. CCLs may independently associate with diminished estimated glomerular filtration rate (eGFR) in stable renal transplant recipients (RTR). METHODS: Plasma levels of 19 CCLs (1, 2, 3, 4, 5, 8, 11, 13, 15, 17, 21, 24, 26, 27, CXCL5, 8, 10, 12 and 13) were measured in a cohort of 101 RTR. The cohort was divided according to CKD-EPI equation into three groups; group 1: eGFR ≥ 60 ml/min, group 2: eGFR 30-59.9 ml/min and group 3 eGFR ≤ 29.9 ml/min. ANOVA, Krusklwallis, Mann- Whitney Spearman correlation and regression analysis tests were used to determine association between reduced eGFR and inflammatory CCLs plasma levels measured by multiplex techniques. 20 healthy subjects with eGFR above 90 ml/min were included as control. Significance was sat at < 0.05. RESULTS: Levels of CCLs 1, 4, 15, 27, CXCL8 and CXCL10 were significantly different among the four studied groups. Multivariate regression analysis (MVA) between eGFR and all CCLs demonstrated that CCL27 was the only ligand to remain significantly associated with diminished eGFR {P = 0.021 and r = - 0.35,(P = 0.001)}. In a second MVA between CCL 27 and patient's demographics and laboratory variables, diminished eGFR, and elevated PTH, out of the twenty one available variables remained significantly associated with elevated CCL27levels. CONCLUSION: Diminished eGFR in stable RTR is associated with elevated plasma levels of CCL27. This association may explain, at least in part, the independent contribution of reduced eGFR to enhanced inflammation in RTR.

Transplant renal vein thrombosis in a recipient with aberrant venous anatomy.

Renal vein thrombosis in a transplanted kidney is an uncommon but critical complication that can result in graft loss if management is delayed. A 31-year-old male with known atresia of the inferior vena cava who received a deceased donor renal transplant 7 years previously presented to hospital with severe graft site pain and a week of nausea, vomiting, and chills. Serum creatinine was markedly elevated from baseline. Sonographic examination revealed external iliac vein thrombosis with extension of the thrombus into the transplant renal vein. Urgent angiographic administration of tissue plasminogen activator and suction thrombectomy was performed, then followed by heparin and clopidogrel post procedure. Within 24 h, his serum creatinine improved, and within 2 weeks returned to his baseline. He was started on lifelong warfarin anti-coagulation to reduce the risk of rethrombosis secondary to his uncorrectable aberrant venous anatomy. Due to the turbulent and sometimes reversed flow in the major veins, lifelong anticoagulation should be strongly considered for such transplant patients with recipient aberrancy of the large veins.

Development of a patient-centered video series to improve education before kidney transplantation.

BACKGROUND: Inadequate patient knowledge about transplantation can result in low patient satisfaction and contribute to poor clinical outcomes. The purpose of this patient-oriented research project was to develop an educational intervention for patients awaiting kidney transplantation. METHODS: An educational intervention was developed by patients and health care providers, experts in medication adherence, video education, motivational psychology, and cultural education. Project objectives were defined and content was guided by a series of studies conducted with stakeholders. A review process was undertaken with additional patients, external health care providers and ninth grade high school students and edits were applied accordingly. RESULTS: A set of six educational videos, ranging in length from 3 to 24 min, was created to describe the transplant process. The videos are patient friendly in design, and incorporate animations to explain complex information to accommodate low health literacy, and patient testimonials align the content with principles of adult learning theory. Feedback from external patient reviews [n = 8], external care providers [n = 13] and students [n = 26], indicate that the mini-series is informative and useful. CONCLUSION: Patient involvement significantly influenced the development of a video series about kidney transplantation. PRACTICE IMPLICATIONS: Patient engagement is integral for developing high quality and relevant educational interventions.