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Background: Extracorporeal membrane oxygenation (ECMO) is a cardiopulmonary bypass device that provides life-saving complete respiratory and cardiac support in patients with cardiorespiratory failure. The majority of drugs prescribed to patients on ECMO lack a dosing strategy optimized for ECMO patients. Several studies demonstrated that dosing is different in this population because the ECMO circuit components can adsorb drugs and affect drug exposure substantially. Saturation of ECMO circuit components by drug disposition has been posited but has not been proven. In this study, we have attempted to determine if propofol adsorption is saturable in ex vivo ECMO circuits. Methods: We injected ex vivo ECMO circuits with propofol, a drug that is highly adsorbed to the ECMO circuit components. Propofol was injected as a bolus dose (50 μg/mL) and a continuous infusion dose (6 mg/h) to investigate the saturation of the ECMO circuit. Results: After the bolus dose, only 27% of propofol was recovered after 30 minutes which is as expected. However, >80% propofol was recovered after the infusion dose which persisted even when the infusion dose was discontinued. Conclusion: Our results suggest that if ECMO circuits are dosed directly with propofol, drug adsorption can be eliminated as a cause for altered drug exposure. Field of Research: Artificial Lung/ECMO

Eukaryotic elongation factor 2 kinase (eEF2K) is overexpressed in a wide variety of cancer types, including hormone receptor positive breast cancer. Targeting of eEF2K has demonstrated anti-tumor activity with the potential of enhanced treatment efficacy in combination with chemotherapy. Here, we describe gold nanoparticle (AuNPs) based delivery of siRNAs enabling eEF2K knockdown in combination with doxorubicin (DOX) to estrogen receptor (ER) positive breast cancer (MCF7) cells. The siRNAs and DOX were co-delivered on the same NP or delivered on separate NPs in a mixture at various siRNA:drug ratios. Effective inhibition of eEF2K expression was provided together with delivery of DOX leading to the enhanced inhibition of cancer cell proliferation compared to DOX delivery alone. siRNA:DOX ratio of 1:2.25 demonstrated synergistic inhibition of cancer cell proliferation. Delivery of eEF2K siRNAs and DOX on separate NPs showed anti-proliferative activity superior to co-delivery on the same NP. These results suggest that eEF2K inhibition enhanced the anticancer activity of chemotherapy on MCF7 breast cancer cells and that the delivery method of the therapeutics had an influence on cytotoxicity. [ABSTRACT FROM AUTHOR]

Immunostimulation caused by nanoparticles may be beneficial or adverse depending on their intended application. Activation of immune cells is beneficial for indications targeting the immune system for therapeutic purposes, such as tumor microenvironment reprogramming, immunotherapy, and vaccines. When it is unwanted, however, immunostimulation may lead to excessive inflammation, cytokine storm, and hypersensitivity reactions. The increasing use of silica nanoparticles (SiNPs) for the delivery of drugs, imaging agents, and antigens warrants preclinical studies aimed at understanding carrier-mediated effects on the number, activation status, and function of immune cell subsets. Herein, we present an in vitro study utilizing primary human peripheral blood mononuclear cells (PBMC) to investigate the proinflammatory properties of four types of SiNPs varying in size and porosity. Cytokine analysis was performed in resting and LPS-primed PBMC cultures to understand the ability of silica nanoparticles to induce de novo and exaggerate preexisting inflammation, respectively. Changes in the number and activation status of lymphoid and myeloid cells were studied by flow cytometry to gain further insight into SiNP-mediated immunostimulation. Nonporous SiNPs were found to be more proinflammatory than mesoporous SiNPs, and larger-sized particles induced greater cytokine response. LPS-primed PBMC resulted in increased susceptibility to SiNPs. Immunophenotyping analysis of SiNP-treated PBMC resulted in T and B lymphocyte, natural killer cell, and dendritic cell activation. Additionally, a loss of regulatory T cells and an increase in γδ TCR T cell population were observed with all particles. These findings have implications for the utility of SiNPs for the delivery of drugs and imaging agents. [ABSTRACT FROM AUTHOR]

Silica nanoparticles are increasingly considered for drug delivery applications. These applications require an understanding of their biocompatibility, including their interactions with the immune system. However, systematic studies for silica nanoparticle immunological safety profiles are lacking. To fill this gap, we conducted an in vitro study investigating various aspects of silica nanoparticles' interactions with blood and immune cells. Four types of silica nanoparticles with variations in size and porosity were studied. These included nonporous Stöber silica nanoparticles with average diameters of approximately 50 and 100 nm (SNP50 and SNP100), mesoporous silica nanoparticles of approximately 100 nm (Meso100), and hollow mesoporous silica nanoparticles of approximately 100 nm (HMSNP100) in diameter, respectively. The hematological compatibility was assessed using hemolysis, complement activation, platelet aggregation, and plasma coagulation assays. The effects of nanoparticles on immune cell function were studied using in vitro phagocytosis, chemotaxis, natural killer cell cytotoxicity, leukocyte proliferation, human lymphocyte activation, colony-forming unit granulocyte-macrophage, and leukocyte procoagulant activity assays. The in vitro findings suggest that at high concentrations, corresponding to the in vivo human dose of 40 mg/kg, silica nanoparticles demonstrated an array of immunotoxic effects that depended on their physicochemical properties. However, all types of silica nanoparticles studied were not immunotoxic at concentrations corresponding to lower doses (≤ 8 mg/kg) comparable to that of nanocarriers in other nanomedicines currently used in the clinic. These findings are promising for using silica nanoparticles for the systemic delivery of bioactive and imaging agents. [ABSTRACT FROM AUTHOR]

Background: Budesonide high-volume saline irrigations (HVSIs) are routinely used to treat chronic rhinosinusitis (CRS) due to improved sinonasal delivery and efficacy compared to intranasal corticosteroid sprays. The off-label use of budesonide is assumed to be safe, with several studies suggesting the systemically absorbed dose of budesonide HVSI is low. However, the actual budesonide dose retained in the sinonasal cavity following HVSI is unknown. The objective of this study was to quantify the retained dose of budesonide after HVSI. Methods: Adult patients diagnosed with CRS who had undergone endoscopic sinus surgery (ESS) and were prescribed budesonide HVSI were enrolled into a prospective, observational cohort study. Patients performed budesonide HVSI (0.5 mg dose) under supervision in an outpatient clinic, and irrigation effluent was collected. High-performance liquid chromatography was employed to determine the dose of budesonide retained after HVSI. Results: Twenty-four patients met inclusion criteria. The average corrected retained dose of budesonide across the cohort was 0.171 ± 0.087 mg (37.9% of administered budesonide). Increased time from ESS significantly impacted the measured retained dose, with those 3 months post-ESS retaining 27.4% of administered budesonide (P =.0004). Conclusion: The retained dose of budesonide in patients with CRS after HVSI was found to be significantly higher than previously estimated and decreased with time post-ESS. Given that budesonide HVSI is a cornerstone of care in CRS, defining the retained dose and the potential systemic implications is critical to understanding the safety of budesonide HVSI. [ABSTRACT FROM AUTHOR]

Sialorrhea or drooling is a common problem in children and adults with neurodevelopmental disorders. It can negatively impact the quality of life due to its physical and psychological manifestations. Providers commonly prescribe atropine eye drops for topical administration to the oral mucosa, as an off‐label treatment to manage sialorrhea. However, the off‐label use of atropine eye drops can be associated with medication and dosing errors and systemic side effects. To address these limitations of treatment, we developed a mucoadhesive topical oral gel formulation of atropine as an alternative route to off‐label administration of atropine eye drops. In this clinical pharmacokinetic (PK) study, we evaluated the safety and PK of atropine gel (0.01% w/w) formulation after single‐dose administration to the oral mucosa in 10 healthy volunteers. The PK data showed that after topical administration to the oral mucosa, atropine followed a two‐compartment PK profile. The maximum plasma concentration and area under the curve extrapolated to infinite time were 0.14 ng/mL and 0.74 h·ng·mL−1, respectively. The absorption rate constant calculated by the compartmental analysis was 0.4 h−1. Safety parameters, such as heart rate, blood pressure, and oxygen saturation, did not significantly change before and after administration of the gel formulation, and no adverse events were observed in all participants who received atropine gel. These data indicate that atropine gel formulation has a satisfactory PK profile, is well‐tolerated at the dose studied, and can be further considered for clinical development as a drug product to treat sialorrhea. [ABSTRACT FROM AUTHOR]