Plasma Exchange Research Articles

Acute Respiratory Distress Syndrome in a Patient with Myasthenia Gravis and Septic Shock: A Case Report

Introduction: Myasthenia gravis (MG) is an autoimmune disorder characterized by muscle weakness, often affecting respiratory and oropharyngeal muscles. This predisposition to respiratory compromise, coupled with impaired swallowing and the potential need for immunosuppressive therapies, increases the risk of pneumonia and subsequent sepsis in MG patients. Sepsis, in turn, is a significant risk factor for acute respiratory distress syndrome (ARDS), a severe lung condition with high mortality. Case presentation: We present the case of a 47-year-old male with a 4-year history of MG who was admitted to our hospital with progressive dyspnea and dysphagia. His condition deteriorated rapidly, leading to septic shock and respiratory failure necessitating invasive mechanical ventilation. Blood cultures identified Klebsiella pneumoniae with extended-spectrum beta-lactamase (ESBL) production. Despite aggressive treatment, including therapeutic plasma exchange (TPE), the patient's hospital course was complicated. Conclusion: This case underscores the critical importance of vigilant monitoring and early intervention in MG patients presenting with respiratory symptoms or signs of infection. Prompt recognition and aggressive management of sepsis are crucial to mitigate the risk of ARDS and improve outcomes in this vulnerable patient population.

Bloodstream infections among patients receiving therapeutic plasma exchanges in the intensive care unit: a 10 year multicentric study

BackgroundTherapeutic plasma exchanges (TPE), which affect the humoral response, are often performed in combination with immunosuppressive drugs. For this reason, TPE may be associated with an increased susceptibility to infections. We aimed to describe blood stream infection (BSI) incidence in ICU patients treated with TPE and to identify associated risk factors.MethodsWe retrospectively included patients that had received at least one session of TPE in the ICU of one of the 4 participating centers (all in Paris, France) between January 1st 2010 and December 31th 2019. Patients presenting with a BSI during ICU stay were compared to patients without such an infection. Risk factors for BSI were identified by a multivariate logistic regression model.ResultsOver 10 years in the 4 ICUs, 387 patients were included, with a median of 5 [2–7] TPE sessions per patient. Most frequent indications for TPE were thrombotic microangiopathy (47%), central nervous system inflammatory disorders (11%), hyperviscosity syndrome (11%) and ANCA associated vasculitis (8.5%). Thirty-one patients (8%) presented with a BSI during their ICU stay, a median of 7 [3–11] days after start of TPE. In a multivariate logistic regression model, diabetes (OR 3.32 [1.21–8.32]) and total number of TPE sessions (OR 1.14 [1.08–1.20]) were independent risk factors for BSI. There was no difference between TPE catheter infection related BSI (n = 11 (35%)) and other sources of BSI (n = 20 (65%)) regarding catheter insertion site (p = 0.458) or rate of TPE catheter related deep vein thrombosis (p = 0.601). ICU course was severe in patients presenting with BSI when compared to patients without BSI, with higher need for mechanical ventilation (45% vs 18%, p = 0.001), renal replacement therapy (42% vs 20%, p = 0.011), vasopressors (32% vs 12%, p = 0.004) and a higher mortality (19% vs 5%, p = 0.010).ConclusionBlood stream infections are frequent in patients receiving TPE in the ICU, and are associated with a severe ICU course. Vigilant monitoring is crucial particularly for patients receiving a high number of TPE sessions.

Unravelling the Acute, Chronic and Steroid-Refractory Management of High-Grade Neurological Immune-Related Adverse Events: A Call to Action.

Rare side effects of immune-checkpoint inhibitors (ICIs) are known as neurological immune-related adverse events (n-irAEs). Typically, n-irAEs affect the peripheral nervous system, primarily presenting as myositis, polyradiculoneuropathy, or cranial neuropathy. Less commonly, they impact the central nervous system, resulting in encephalitis, meningitis, or myelitis. High-grade n-irAEs managing and recognizing remains challenging, considering the risk of mortality and long-term disability. To date, strong scientific data are lacking to support the management of high-grade clinical forms. We performed a systematic literature search, selecting all articles describing high-grade steroid-resistance n-irAEs. and we reported them in a practical review. Specifically, current recommendations advise stopping ICI use and beginning corticosteroid treatment. Our findings highlighted that in steroid-resistant n-irAEs, it should be recommended to quickly escalate to plasma exchange (PLEX) and/or intravenously immunoglobulins (IVIg), usually in association with other immunosuppressants. Furthermore, newer evidence supports the use of drugs that may specifically block inflammation without reducing the anti-tumour effect of ICIs. In this practical review, we provide new evidence regarding the therapeutic approach of high-grade n-irAEs, particularly in steroid-resistant cases. We would also stress the importance of informing the scientific community of the discrepancy between current guidelines and clinical evidence in these rare forms of pathology.

Antimicrobial management in patients undergoing therapeutic plasma exchange: A Cross-Sectional Nationwide Survey.

There is little evidence of antimicrobial elimination via therapeutic plasma exchange (TPE) and no guidelines for antimicrobial optimal dosing in patients undergoing TPE. We aimed to assess current practices and knowledge regarding antimicrobial management during TPE. A structured online survey was conducted from May to November 2023, and physicians were invited to participate through national scientific platforms and professional societies. One hundred five participants completed the survey, of whom 61% were infectious disease physicians, with 68.6% having more than 10 years of experience. That the TPE procedure could significantly affect plasma concentrations of antimicrobial agents was reported by 74.3% of the respondents. Among the physicians, 42.9% suggest antimicrobial dose adjustment, and 38.1% recommend temporarily discontinuing antimicrobial drug administration during TPE. Therapeutic drug monitoring was recommended by 33.3% of the respondents for certain antimicrobials, mainly glycopeptides and aminoglycosides, in patients undergoing concurrent TPE. Furthermore, 59.3% of physicians sometimes consult with another healthcare professional for treatment management, most commonly a pharmacist or a clinical pharmacist and an infectious diseases specialist. The core questions regarding potential drug-, procedure-, and patient-related antimicrobial elimination factors via TPE were responded to accurately by less than half of the physicians. It was clear that they had a lack of clinical practices and knowledge regarding antimicrobial management during TPE. To ensure the therapeutic efficacy of antimicrobials and avoid treatment failure, physicians should improve their practice strategies and consider antimicrobial elimination factors with TPE in this data-poor setting.

Clinical presentation and symptomatology of Guillain-Barré syndrome: A literature review.

Guillain-Barré Syndrome (GBS) is a rare but potentially life-threatening neurological disorder characterized by acute onset ascending paralysis and sensory abnormalities. This article provides a comprehensive overview of GBS, covering its epidemiology, etiology, clinical presentation, diagnostic evaluation, management and treatment, prognosis, psychosocial impact, recent advances in research, public health implications, and ethical considerations. Epidemiological data reveal variations in GBS prevalence, incidence rates, and geographical distribution influenced by climate, infectious disease prevalence, and genetic susceptibility. Etiological factors include preceding infections, vaccinations, and autoimmune mechanisms, although the precise pathophysiology remains incomplete. Clinical presentation encompasses prodromal symptoms, motor deficits, sensory abnormalities, autonomic dysfunction, and variants such as Miller-Fisher Syndrome and Bickerstaff brainstem encephalitis. Neurological examination findings include weakness, paralysis, sensory deficits, and reflex changes, while autonomic dysfunction manifests as cardiovascular, respiratory, and gastrointestinal symptoms. Diagnostic evaluation relies on clinical criteria, laboratory tests (e.g., cerebrospinal fluid analysis, nerve conduction studies), and consideration of differential diagnoses. Management strategies encompass supportive care, immunomodulatory therapies (e.g., intravenous immunoglobulin, plasma exchange), and rehabilitation interventions to optimize functional outcomes and promote recovery. Prognosis varies depending on clinical features, treatment response, and complications such as respiratory failure and autonomic instability. Psychosocial impact encompasses psychological effects on patients and caregivers, highlighting the importance of coping strategies and support systems. Recent advances in research focus on emerging treatments, genetic predisposition, and biomarker discovery, offering promise for improving GBS outcomes. Public health implications include vaccination safety concerns and healthcare system considerations for GBS management. Ethical considerations encompass patient autonomy, resource allocation, and end-of-life decision-making.

Incidence of SARS-CoV-2 during the Omicron wave: Results of a longitudinal serosurvey in Québec, Canada.

Conventional serological approaches lack sensitivity for the detection of recent SARS-CoV-2 infections in vaccinated individuals, as these individuals exhibit a blunted anti-nucleocapsid (N) response. This limitation was recently addressed by the development of a "ratio-based approach", which compares longitudinally collected specimens. Here, we used this approach to estimate the incidence of SARS-CoV-2 infection and reinfection in Québec (Canada) during the Omicron wave. Consenting plasma donors were included if they donated plasma before December 15, 2021 and during six consecutive periods of ~ 3months between December 15, 2021 and July 7, 2023 (study period). Anti-N levels were measured with an enzyme-linked immunosorbent assay, and seroconversion was characterized by a ratio of ≥ 1.5 between the optical density of two consecutive samples. Among the 254 donors, the adjusted proportion of donors (95% confidence interval [CI]) with a new infection ranged between 18.1% (13.2‒23.0) and 24.2% (18.8‒29.7) over Periods 1-5 and fell to 7.9% (4.9‒11.0) during Period 6. During the study period, the proportion of newly infected donors decreased among those aged < 60 (Period 1 = 31.6%, Period 5 = 4.4%), but increased among those aged ≥ 70 (Period 1 = 0.3%, Period 6 = 10.3%). Throughout the study period, 72 (28.3%) reinfections occurred, including two seroconversion events in a single donor. Overall, 87.4% (95% CI = 82.7‒91.2) were infected by SARS-CoV-2 at least once during the study period. The vast majority of the Québec population may have been infected during the Omicron wave. This longitudinal survey demonstrates the usefulness of the "ratio-based approach" for identifying both new infections and reinfections in a vaccinated population.

A 32-year old lady who developed a complex generalized movement disorder in all four limbs after plasma exchange for myelitis

A 32-year old lady with AQP4-Antibody positive neuromyelitis optica developed a new-onset complex movement disorder after therapeutic plasma exchange, which was initially suspected to be hypocalcemic carpo-pedal spasm. However, when her bilateral, distal predominant, paroxysmal, stereotypic, wrist and finger flexor tonic contractions did not respond to serum calcium correction, other diagnoses were considered. The patient had a dramatic response to oral carbamazepine suggesting that the tonic spasms were likely a spinal movement disorder due to the primary demyelinating pathology.

Indoor air disinfection by non thermal atmospheric pressure plasma: a comparative study of performance in low and high humidity environments

Atmospheric pressure plasma (APP) has intrigued the interest of researchers for various applications such as disinfection, air purification, etc. In this context, a deeper understanding of the correlation between APP’s characteristics like discharge parameters, active species composition, and eradication of airborne microorganisms with varying relative humidity (RH) has been examined using a dielectric barrier discharge based atmospheric pressure plasma (DBD-APP) source. One of the electrodes of the developed DBD-APP source has been coated with TiO2 nanoparticles to enhance the generation of reactive species during the discharge process. The results show that, even with the same peak-to-peak applied voltage, the peak-to-peak current and discharge power decrease with increasing RH. Optical emission spectroscopy (OES) is used to determine the relative emission intensity of the reactive species, whereas spectrophotometry is used to quantify the reactive species produced by the plasma at various parameters. Instead of UV radiation, the plasma-produced highly energetic electrons activates the TiO2 nanoparticles for electron–hole pair generation. The geometry of the plasma device has played an important role in generating high energy electrons. From the developed DBD-APP source, the airborne microorganism’s disinfection efficiency of ∼95.8% and ∼98.7% has been achieved in the total bacterial counts (TBCs) and total fungal counts (TFCs) at an RH range of 70%–90%, in just 20 min of continuous operation. However, in the RH range of 20%–40%, the inactivation efficiency dropped to ∼78.8% and ∼87.5% for the TBCs and TFCs, respectively. The outcome indicates that higher humidity levels are better for indoor air purification using DBD-APP sources and that plasma with a circulation system can effectively disinfect indoor environments.

Therapeutic plasma exchange in autoimmune neurological disorders: A comprehensive evaluation of clinical outcomes, safety, and long-term disability using the modified Rankin scale.

Autoimmune neurological diseases (ANDs) involve the immune system attacking the nervous system, leading to various symptoms. Therapeutic plasma exchange (TPE) is used to remove pathogenic autoantibodies, aiming to improve clinical outcomes. This ambispective observational study included 99 patients with ANDs who underwent TPE from January 2018 to June 2022 at a tertiary care center in India. Clinical outcomes were measured using the modified Rankin Scale (mRS) scores at admission, post-TPE, at 3-months, 6-months, and 1-year follow-up post-discharge. Data were analyzed using Epi Info version 7.0. The median mRS score improved significantly from 5 (IQR 4-5) before TPE to 3 (IQR 2-4) post-TPE (p < 0.001). Complications occurred in 5.95% of procedures, with allergic reactions being the most common. The in-hospital mortality rate was 9%. TPE is a safe and effective treatment modality for autoimmune neurological diseases, especially in resource-constrained settings. It aids in both symptomatic relief and reducing long-term functional disability.

Beneficial therapeutic plasma exchange response in the treatment of severe relapses in patients with multiple sclerosis.

Therapeutic plasma exchange (PLEX) is effective as a second-line treatment of severe relapses of multiple sclerosis (MS) that failed to respond to standard steroid therapy. Our objective was to evaluate the effectiveness of PLEX in the severe MS relapses in a cohort of patients treated at Neurology Clinic, University Clinical Centre of Serbia, Belgrade, from 2007 until 2020. This retrospective study comprised 107 MS patients with 127 severe relapses treated with PLEX. Majority of our patients suffered from relapsing remitting MS (83.2%), 12.1% had secondary progressive MS and 4.7% had primary progressive MS. Mean age was 39.2 years (range, 19-79 years), female/male ratio 2.3:1. Pulse corticosteroid treatment was used before PLEX in 99.3% of patients. Median EDSS score at nadire during relapse was 6.0 (range 2.0-10.0). After PLEX, 73.8% relapses showed a marked clinical improvement, 7.1% showed mild improvement and in 19.0% there was no improvement. Median EDSS at discharge was 4.0 (6.0 at nadir of relapse vs. 4.0 at discharge; p<0.0001) and it was sustained at the same level, 6 month after PLEX. Multivariate regression analysis showed that higher EDSS at nadir during relapse (OR=0.63, 95% CI 0.41-0.96, p=0.039) and older age (OR=1.07, 95% CI 1.02- 1.12, p=0.010) were significantly associated with poor treatment response after 6- month follow-up. Adverse events occurred in 17.3 of procedures and they were completely resolved. Our study in a large cohort of MS patients confirmed that PLEX is effective.

Pure Red Cell Aplasia - Post Major ABO Incompatible Allogenic Stem Cell Transplantation Role of Ibrutinib

Pure Red Cell Aplasia (PRCA) is a well-recognized complication of Major ABO-incompatible allogeneic stem cell transplantation. It is featured by anemia, Reticulocytopenia, and the absence of erythroblasts in a normal-appearing bone marrow biopsy. The mechanism for PRCA is presumed to be the persistence of recipient isoagglutinins, produced by residual host B lymphocytes or plasma cells, which probably interfere with the engraftment of donor erythroid cells. Several risk factors for PRCA have been reported, such as the presence of Anti-A Isoagglutininsbefore transplantation, reduced intensity conditioning, absence of Graft Versus Host Disease (GVHD), sibling donor and Cyclosporin A(CsA) as GVHD prophylaxis. PRCA is not a barrier to going ahead with Hematopoietic Stem Cell Transplantation (HSCT). There are many therapeutic options however few recover spontaneously, among the available options include high-dose steroids, Erythropoietin(EPO), Plasma exchange, Donor lymphocyte Infusion (DLI), treatment with Rituximab, Bortezomib, Daratumumab and tapering or discontinuation of immunosuppression. All these options have variable success in the literature ranging from 30% - 70%, Non-responders become red cell transfusion dependent and their quality of life is impaired. We are reporting a novel therapeutic option, Ibrutinib as an armamentarium in treating the PRCA post-HSCT, which works by blocking the Bruton Tyrosine Kinase (BTK) pathway thereby inhibiting the host B cell isoagglutinins production and good clinical response.

Auxiliary Partial Orthotopic Liver Transplantation Is a Safe and Effective Option for Yellow Phosphorus Toxin-induced Acute Liver Failure.

Ingestion of yellow phosphorus-containing rodenticides (YPR) or firecrackers is an important cause of acute liver failure (ALF) in young adults and children, particularly in South and South-East Asia and South America. Emergency liver transplantation is indicated in cases refractory to intensive supportive therapy, including low-volume plasma exchange. There are no published reports on the feasibility of auxiliary partial orthotopic liver transplantation (APOLT) for YPR-induced ALF. Clinical details of patients undergoing APOLT for YPR-induced ALF in 1 unit are reported. Details of postoperative follow-up, native remnant regeneration, and immunosuppression withdrawal are also reported. Between January 2021 and December 2023, 3 patients (4 y, 1.5 y, and 26 y) underwent emergency living donor liver transplantation for YPR-induced ALF. All patients were refractory to supportive therapies, including therapeutic plasma exchange, and demonstrated progression of liver injury in the form of severe encephalopathy needing intubation, ventilation, and organ support. APOLT was considered because of their young age and minimal intraoperative inotropic requirement. All explants showed confluent parenchymal necrosis with microvesicular and macrovesicular steatosis. Patients were initially maintained on standard immunosuppression. Good remnant regeneration was noted on follow-up imaging in all cases, enabling gradual withdrawal of immunosuppression. Currently, 1 child has been off immunosuppression for 15 mo and 2 others are on reduced doses of immunosuppression. All patients demonstrated good liver function. APOLT procedure can be an appropriate transplant option in YPR-related ALF for children and young adults without severe hemodynamic instability.

Toroidal CO2 Plasma Sources with Low- and High-Frequency Power Coupling Configurations for Improved Energy Transfer Efficiencies

Toroidal CO2 Plasma Sources with Low- and High-Frequency Power Coupling Configurations for Improved Energy Transfer Efficiencies

A randomised controlled trial of plasma exchange compared to standard of care in the treatment of severe COVID-19 infection (COVIPLEX)

COVID-19 disease is associated with a hyperinflammatory, pro-thrombotic state and a high mortality. Our primary objective was to assess the change in inflammatory and thrombotic markers associated with PEX, and secondary objectives were to assess the effects of PEX on progression of respiratory failure and incidence of acute thrombotic events. We conducted a prospective, phase II, non-blinded randomised control trial of plasma exchange compared to standard of care in critically ill adults with severe COVID-19 associated respiratory failure, requiring supplemental oxygen or ventilatory support and elevated thrombo-inflammatory markers (LDH, CRP, ferritin, and D-Dimer). Patients randomised to receive PEX were treated with a daily single volume plasma exchange for a minimum of five days. Twenty-two patients were randomised of who 11 received PEX. Demographic and clinical characteristics were similar between groups at presentation. PEX was associated with a significant reduction in pro-thrombotic markers FVIII, VWF and VWF Ag: ADAMTS 13 ratio (p < 0.001). There were no differences in the reduction of inflammatory markers, severity of respiratory failure (p = 0.7), thrombotic events (p = 0.67), or mortality (p > 0.99) at 28 days. PEX successfully reduced pro-thrombotic markers, although was not associated with reduction in inflammatory markers, respiratory failure, or thrombotic events.Trial registration: (NCT04623255); first posted on 10/11/2020.

Effect of dielectric material on the uniformity of nanosecond pulsed dielectric barrier discharge

Dielectric barrier discharge (DBD) is considered as a promising technique to produce large volume uniform plasma at atmospheric pressure, and the dielectric barrier layer between the electrodes plays a key role in the DBD processes and enhancing discharge uniformity. In this work, the uniformity and discharge characteristics of the nanosecond (ns) pulsed DBD with dielectric barrier layers made of alumina, quartz glass, polycarbonate (PC), and polypropylene (PP) are investigated via discharge image observation, voltage-current waveform measurement and optical emission spectral diagnosis. Through analyzing discharge image by gray value standard deviation method, the discharge uniformity is quantitatively calculated. The effects of the space electric field intensity, the electron density (N e), and the space reactive species on the uniformity are studied with quantifying the gap voltage U g and the discharge current I g, analyzing the recorded optical emission spectra, and simulating the temporal distribution of N e with a one-dimensional fluid model. It is found that as the relative permittivity of the dielectric materials increases, the space electric field intensity is enhanced, which results in a higher N e and electron temperature (T e). Therefore, an appropriate value of space electric field intensity can promote electron avalanches, resulting in uniform and stable plasma by the merging of electron avalanches. However, an excessive value of space electric field intensity leads to the aggregation of space charges and the distortion of the space electric field, which reduce the discharge uniformity. The surface roughness and the surface charge decay are measured to explain the influences of the surface properties and the second electron emission on the discharge uniformity. The results in this work give a comprehensive understanding of the effect of the dielectric materials on the DBD uniformity, and contribute to the selection of dielectric materials for DBD reactor and the realization of atmospheric pressure uniform, stable, and reactive plasma sources.

Anti-HNA testing of allo-exposed COVID-19 convalescent plasma donors including genetic human neutrophil antigen screening to prevent anti-HNA antibody-mediated transfusion-related acute lung injury.

Transfusion-related acute lung injury caused by antibodies against human neutrophil antigens (HNA) is a serious but rare complication associated with blood transfusion. The presence of such antibodies is most probable in donors with a transfusion/pregnancy history. During the COVID-19 pandemic period convalescent plasma (CP) containing neutralizing antibodies against SARS-CoV-2 was widely used for COVID-19 patients as a therapy in the absence of any treatment. The aim of the study was to work out a simple diagnostic algorithm of anti-HNA testing of allo-exposed CP donors including genetic HNA screening. A total of 457 anti-HLA-negative allo-exposed CP donors were genotyped for HNA-1a/1b, HNA-3a/3b, and HNA-2, and only donors with homozygous HNA-1a/1a; HNA-3b/3b; or HNA-2null genotypes were tested for anti-HNA antibody using LabScreenMulti (One Lambda) and homozygous HNA-1b/1b using the granulocyte immunofluorescence test (GIFT) but verified using LabScreenMulti. Testing of 83 homozygous HNA-3b/3b; HNA-2null; or HNA-1a/1a donors revealed anti-HNA-3a antibody in one case. Testing of 181 HNA-1b/1b donors using GIFT gave 10 ambiguous results verified using LabScreenMulti which confirmed anti-HNA-1a antibody in one case. The frequency of FCGR3B*01 and *04 encoding HNA-1a was 0.34; FCGR3B*02, *03, and *05 encoding HNA-1b-0.66; SLC44A2*01 encoding HNA-3a-0.80; and SLC44A2*02 encoding HNA-3b-0.20. In 3.7% cases the HNA-2null genotype was revealed. Due to applying HNA genotyping as a primary test before anti-HNA antibody testing the serological work was limited only to HNA-homozygous donors revealing two anti-HNA immunized donors. The distribution of HNA genotypes in the cohort was similar to other Caucasian populations.

Therapeutic plasma exchange for hyperviscosity syndrome in IgA multiple myeloma.

Hyperviscosity syndrome (HVS) is defined as the symptomatic presentation of increased blood thickness due to various clinical conditions such as hypergammaglobulinemia. HVS secondary to immunoglobulin (Ig)A multiple myeloma has been infrequently reported. Although the efficiency of IgM or IgG removal by therapeutic plasma exchange (TPE) is well described, the efficiency of IgA removal by TPE is not as well known. Here, we describe a case of HVS due to IgA myeloma in a patient who received 2 TPE treatments, with subsequent symptomatic improvement as well as decrease in IgA and viscosity levels.

A Cross-Sectional Study of Measles-Specific Antibody Levels in Australian Blood Donors-Implications for Measles Post-Elimination Countries.

Passive immunisation with normal human immunoglobulin (NHIG) is recommended as post-exposure prophylaxis (PEP) for higher-risk measles contacts where vaccination is contraindicated. However, the concentration of measles-specific antibodies in NHIG depends on antibody levels within pooled donor plasma. There are concerns that measles immunity in the Australian population may be declining over time and that blood donors' levels will progressively decrease, impacting levels required to produce effective NHIG for measles PEP. A cross-sectional study of Australian plasmapheresis donors was performed using an age-stratified, random sample of recovered serum specimens, collected between October and November 2019 (n = 1199). Measles-specific IgG antibodies were quantified by ELISA (Enzygnost anti-measles virus IgG, Siemens), and negative and equivocal specimens (n = 149) also underwent plaque reduction neutralisation testing (PRNT). Mean antibody levels (optical density values) progressively decreased from older to younger birth cohorts, from 2.09 [±0.09, 95% CI] to 0.58 [±0.04, 95% CI] in donors born in 1940-1959 and 1990-2001, respectively (p < 0.0001). This study shows that mean measles-specific IgG levels are significantly lower in younger Australian donors. While current NHIG selection policies target older donors, as younger birth cohorts become an increasingly larger proportion of contributing donors, measles-specific antibody concentrations of NHIG will progressively reduce. We therefore recommend monitoring measles-specific antibody levels in future donors and NHIG products in Australia and other countries that eliminated measles before the birth of their youngest blood donors.

Characterization of a radially emitting spray jet in a cylindrical inertial electrostatic confinement plasma source based on particle in cell simulation

This paper investigates the outflow mechanism of a cylindrical inertial electrostatic confinement plasma source using Particle in Cell plasma simulations. Various phenomena such as ion-wall interactions, impact ionization, excitation, and secondary electron generation are considered. Together with a fine time and cell resolution to reveal relevant phenomena. The results indicate a high electron and ion density in front of the cathode at the widest grid opening, which suggests the formation of a cascade-like charge carrier emission, commonly referred to as the “spray jet”. Initially, a virtual anode is formed within the cathode grid and is shifted toward the grid opening as time elapsed. Ions are accelerated in the plasma sheath around the cathode and collide with the cathode grids or oscillate through the grid opening. Electrons are accelerated and ionize the background gas at the plasma sheath edge. While the electron flow is disordered within the cathode it forms a cascade-like quasi-neutral plasma at the outlet of the plasma source. Through the formation of a virtual anode the discharge becomes self-sustained. With this simulation results the working principle of the inertial electrostatic confinement plasma source can be derived.

A hierarchal model for bacterial cell inactivation in solution by direct and indirect treatment using cold atmospheric plasmas

Cold atmospheric plasma devices have shown promise for a variety of plasma medical applications, including wound healing and bacterial inactivation often performed in liquids. In the latter application, plasma-produced reactive oxygen and nitrogen species (RONS) interact with and damage bacterial cells, though the exact mechanism by which cell damage occurs is unclear. Computational models can help elucidate relationships between plasma-produced RONS and cell killing by enabling direct comparison between dissimilar plasma devices and by examining the effects of changing operating parameters in these devices. In biological applications, computational models of plasma-liquid interactions would be most effective in design and optimization of plasma devices if there is a corresponding prediction of the biological outcome. In this work, we propose a hierarchal model for planktonic bacterial cell inactivation by plasma produced RONS in liquid. A previously developed reaction mechanism for plasma induced modification of cysteine was extended to provide a basis for cell killing by plasma-produced RONS. Results from the model are compared to literature values to provide proof of concept. Differences in time to bacterial inactivation as a function of plasma operating parameters including gas composition and plasma source configuration are discussed. Results indicate that optimizing gas-phase reactive nitrogen species production may be key in the design of plasma devices for disinfection.