A Role of Circuit Clotting and Strategies to Prevent It during Blood Purification Therapy with oXiris Membrane: An Observational Multicenter Study.

INTRODUCTION: Membrane fouling is a significant complication potentially reducing clinical effects of extracorporeal blood purification (EBP) in critically ill septic patients with acute kidney injury. Although fascinating, the effect of heparin coating in preventing membrane fouling is currently unknown. This multicenter prospective study aims to preliminary describe the incidence, associated factors, and clinical consequences of premature circuit clotting in a cohort of adult critically ill septic patients treated with EBP using a high biocompatible heparin-coated hemodiafilter characterized by advanced adsorption properties. METHODS: This study was a retrospective analysis of prospectively entered data in the oXirisNet Registry; overall, 97 septic patients undergoing EBP with oXiris between May 2019 and March 2020 were enrolled in this study. Patients were divided into two groups according to the occurrence of filter clotting (premature vs. nonpremature). Logistic regression analysis was used to identify factors associated with premature circuit clotting. RESULTS: Premature clotting occurred in 18 (18.6%) patients. Results of the multivariate logistic regression analysis demonstrated that hematocrit (p = 0.02, odds ratio [OR] 1.15 [1.05; 1.30]), serum procalcitonin (PCT) (p = 0.03, OR 1.1 [1.05; 1.2]), and anticoagulation strategy (p = 0.05 at Wald's test) were independent predictors of circuit clotting. Systemic anticoagulation (p = 0.02, OR 0.03 [0.01; 0.52]) and regional citrate anticoagulation (p = 0.10, OR 0.23 [0.04; 1.50]) were both protective factors if compared to no-anticoagulation strategy. Patients with nonpremature circuit clotting showed more rapid recovery from hemodynamic instability, pulmonary hypo-oxygenation, and electrolyte disorders and greater improvement of inflammatory markers and SOFA scores. CONCLUSION: Although in this study the incidence of premature circuit clotting was relatively low (18.6%) compared to previously reported values (54%), membrane clotting in adult critically ill septic patients could cause clinically relevant interferences with treatment performances. Prevention of clotting should be based on avoiding higher patients' hematocrit, high serum PCT, and no-anticoagulation strategy which resulted as independent predictors of circuit clotting.

Methods for dose quantification in continuous renal replacement therapy: Toward a more precise approach.

Periodic dose assessment is quintessential for dynamic dose adjustment and quality control of continuous renal replacement therapy (CRRT) in critically ill patients with acute kidney injury (AKI). The flows-based methods to estimate dose are easy and reproducible methods to quantify (estimate) CRRT dose at the bedside. In particular, quantification of effluent flow and, mainly, the current dose (adjusted for dialysate, replacement, blood flows, and net ultrafiltration) is routinely used in clinical practice. Unfortunately, these methods are critically influenced by several external unpredictable factors; the estimated dose often overestimates the real biological delivered dose quantified through the measurement of urea clearance (the current effective delivered dose). Although the current effective delivered dose is undoubtedly more precise than the flows-based dose estimation in quantifying CRRT efficacy, some limitations are reported for the urea-based measurement of dose. This article aims to describe the standard of practice for dose quantification in critically ill patients with AKI undergoing CRRT in the intensive care unit. Pitfalls of current methods will be underlined, along with solutions potentially applicable to obtain more precise results in terms of (a) adequate marker solutes that should be used in accordance with the clinical scenario, (b) correct sampling procedures depending on the chosen indicator of transmembrane removal, (c) formulas for calculations, and (d) quality controls and benchmark indicators.

Oxiris Membrane in Sepsis and Multiple Organ Failure.

Sepsis and multiple organ failure (MOF) are characterized by multiple hemodynamic changes and imbalanced immune response of the patient. Oxiris is a highly adsorptive membrane with the ability to remove cytokines and endotoxins, as well as to perform renal replacement therapy. Here we describe the evolution from previous AN69 to the 3-in-1 Oxiris membrane, and review its characteristics and performance. In clinical practice, Oxiris showed consistent effects in mean arterial pressure recovery, a decrease in vasopressor needs, and reduction of the Sequential Organ Failure Assessment score. These results have been reproduced by several independent studies addressing both sepsis and, to a lesser extent, COVID-19 patients. In addition, more recent studies in sepsis showed improvements in MOF duration and the length of stay in the ICU, as well as some promising results regarding mortality. Finally, we review ongoing clinical trials and discuss its potential significance to clinical practice improvement and to further reinforce knowledge on the use of blood purification in sepsis and acute kidney injury.

Development of a new delivery system consisting in 'drug-in cyclodextrin-in PLGA nanoparticles'.

A combined approach based on drug cyclodextrin (CD) complexation and loading into PLGA nanoparticles (NP) has been developed to improve oxaprozin therapeutic efficiency. This strategy exploits the solubilizing and stabilizing properties of CDs and the prolonged-release and targeting properties of PLGA NPs. Drug-loaded NPs, prepared by double-emulsion, were examined for dimensions, zeta-potential and entrapment efficiency. Solid-state studies demonstrated the absence of drug-polymer interactions and assessed the amorphous state of the drug-CD complex loaded into NPs. Drug release rate from NPs was strongly influenced by the presence and kind of CD used. The percentage released at 24 h varied from 16% (plain drug-loaded NPs) to 50% (drug-betaCD-loaded NPs) up to 100% (drug-methylbetaCD-loaded NPs). This result suggests the possibility of using CD complexation not only to promote, but also to regulate drug release rate from NPs, by selecting the proper type of CD or CD combination.

Determination of tissue levels of a neuroprotectant drug: the cell permeable JNK inhibitor peptide.

INTRODUCTION: Cell permeable peptides (CPPs) represent a novel tool for the delivery of bioactive molecules into scarcely accessible organs, such as the brain. CPPs have been successfully used in pre-clinical studies for a variety of diseases, ranging from cancer to neurological disorders. However, the mechanisms by which CPPs cross biological membranes, as well as their pharmacokinetic properties, have been poorly explored due to the lack of specific and sensitive analytical methods. METHODS: In this paper we describe a protocol to quantitatively determine the amount of CPPs in in vitro and in vivo experimental models. To this end we selected the peptide D-JNKI1 that was shown to prevent neurodegeneration in both acute and chronic degenerative disorders. This method allows an accurate quantitative analysis of D-JNKI1 in both neuronal lysates and tissue homogenates using mass spectrometry and stable isotope dilution approach. RESULTS: We found that D-JNKI1 crosses cellular membranes with fast kinetics, through an active and passive mechanism. After acute intraperitoneal (ip) administration of D-JNKI1 in mice, the peptide was found in the main organs with particular regard to the liver and kidney. Interestingly, D-JNKI1 crosses the blood brain barrier (BBB) and reaches the brain, where it remains for one week. DISCUSSION: The challenge lies in developing the clinical application of therapeutic cell permeable peptides. Discerning pharmacokinetic properties is a high priority to produce a powerful therapeutic strategy. Overall, our data shed light on the pharmacokinetic properties of D-JNKI1 and supports its powerful neuroprotective effect.

Plasma amino acids patterns and age of onset of amyotrophic lateral sclerosis.

The aim of this study was to verify whether abnormalities in plasma amino acid (AA) levels could be biological correlates of the age of onset in amyotrophic lateral sclerosis (ALS). We undertook plasma AA profiling in a large population comprising 117 newly diagnosed ALS patients and 117 matched controls. ALS patients were stratified in early (58 patients aged < 55 years) versus late onset (59 patients aged > 74 years). We applied a rapid and reproducible method for the analysis of AA using amine reactive isotope coded tags in conjunction with liquid chromatography coupled to Multiple Reaction Monitoring-Mass Spectrometry. Results showed that values of only three AA were significantly different in ALS patients and controls. We found lower levels of leucine and higher levels of glutamate and leucine in early-onset ALS compared to their matched controls. In conclusion, different AA patterns related to the ALS age of onset were found, providing insight into possibly aberrant biochemical pathways that might unlock key pathological pathways.

Whole-blood global DNA methylation is increased in amyotrophic lateral sclerosis independently of age of onset.

ALS is a heterogeneous disease that is not well understood. Epigenetic rearrangements are important in complex disorders including motor neuron diseases. The aim of this study was to determine whether whole-blood DNA methylation (DNA MET %) is a potential modifier of age at onset in ALS. DNA MET % was measured as incorporation of [(3)H]dCTP following HpaII cut in 96 ALS patients and 87 controls, comprising: early-onset (< 55 years of age) and late-onset (> 74 years of age). Methionine (Met) and homocysteine (Hcy) plasma levels were assessed by liquid chromatography selected reaction monitoring coupled with isotope-dilution mass spectrometry. Results showed that DNA MET % was increased in ALS patients independently of age of onset. Compared to the other three groups, Hcy plasma levels were reduced in early-onset ALS patients but Met levels were similar. ROC analysis reported Met levels and DNA MET %, respectively, with a slight and moderate discriminative power. In conclusion, increased DNA MET % is a possible marker of epigenetic dysfunction in ALS independently of age of onset. Further studies dissecting biological determinants of phenotypic complexity in ALS may help in developing successful therapeutic strategies.